gold/x86_64.cc

   1 // x86_64.cc -- x86_64 target support for gold.
   2
   3 // Copyright (C) 2006-2019 Free Software Foundation, Inc.
   4 // Written by Ian Lance Taylor <iant@google.com>.
   5
   6 // This file is part of gold.
   7
   8 // This program is free software; you can redistribute it and/or modify
   9 // it under the terms of the GNU General Public License as published by
  10 // the Free Software Foundation; either version 3 of the License, or
  11 // (at your option) any later version.
  12
  13 // This program is distributed in the hope that it will be useful,
  14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 // GNU General Public License for more details.
  17
  18 // You should have received a copy of the GNU General Public License
  19 // along with this program; if not, write to the Free Software
  20 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  21 // MA 02110-1301, USA.
  22
  23 #include "gold.h"
  24
  25 #include <cstring>
  26
  27 #include "elfcpp.h"
  28 #include "dwarf.h"
  29 #include "parameters.h"
  30 #include "reloc.h"
  31 #include "x86_64.h"
  32 #include "object.h"
  33 #include "symtab.h"
  34 #include "layout.h"
  35 #include "output.h"
  36 #include "copy-relocs.h"
  37 #include "target.h"
  38 #include "target-reloc.h"
  39 #include "target-select.h"
  40 #include "tls.h"
  41 #include "freebsd.h"
  42 #include "nacl.h"
  43 #include "gc.h"
  44 #include "icf.h"
  45
  46 namespace
  47 {
  48
  49 using namespace gold;
  50
  51 // A class to handle the .got.plt section.
  52
  53 class Output_data_got_plt_x86_64 : public Output_section_data_build
  54 {
  55  public:
  56   Output_data_got_plt_x86_64(Layout* layout)
  57     : Output_section_data_build(8),
  58       layout_(layout)
  59   { }
  60
  61   Output_data_got_plt_x86_64(Layout* layout, off_t data_size)
  62     : Output_section_data_build(data_size, 8),
  63       layout_(layout)
  64   { }
  65
  66  protected:
  67   // Write out the PLT data.
  68   void
  69   do_write(Output_file*);
  70
  71   // Write to a map file.
  72   void
  73   do_print_to_mapfile(Mapfile* mapfile) const
  74   { mapfile->print_output_data(this, "** GOT PLT"); }
  75
  76  private:
  77   // A pointer to the Layout class, so that we can find the .dynamic
  78   // section when we write out the GOT PLT section.
  79   Layout* layout_;
  80 };
  81
  82 // A class to handle the PLT data.
  83 // This is an abstract base class that handles most of the linker details
  84 // but does not know the actual contents of PLT entries.  The derived
  85 // classes below fill in those details.
  86
  87 template<int size>
  88 class Output_data_plt_x86_64 : public Output_section_data
  89 {
  90  public:
  91   typedef Output_data_reloc<elfcpp::SHT_RELA, true, size, false> Reloc_section;
  92
  93   Output_data_plt_x86_64(Layout* layout, uint64_t addralign,
  94                          Output_data_got<64, false>* got,
  95                          Output_data_got_plt_x86_64* got_plt,
  96                          Output_data_space* got_irelative)
  97     : Output_section_data(addralign), tlsdesc_rel_(NULL),
  98       irelative_rel_(NULL), got_(got), got_plt_(got_plt),
  99       got_irelative_(got_irelative), count_(0), irelative_count_(0),
 100       tlsdesc_got_offset_(-1U), free_list_()
 101   { this->init(layout); }
 102
 103   Output_data_plt_x86_64(Layout* layout, uint64_t plt_entry_size,
 104                          Output_data_got<64, false>* got,
 105                          Output_data_got_plt_x86_64* got_plt,
 106                          Output_data_space* got_irelative,
 107                          unsigned int plt_count)
 108     : Output_section_data((plt_count + 1) * plt_entry_size,
 109                           plt_entry_size, false),
 110       tlsdesc_rel_(NULL), irelative_rel_(NULL), got_(got),
 111       got_plt_(got_plt), got_irelative_(got_irelative), count_(plt_count),
 112       irelative_count_(0), tlsdesc_got_offset_(-1U), free_list_()
 113   {
 114     this->init(layout);
 115
 116     // Initialize the free list and reserve the first entry.
 117     this->free_list_.init((plt_count + 1) * plt_entry_size, false);
 118     this->free_list_.remove(0, plt_entry_size);
 119   }
 120
 121   // Initialize the PLT section.
 122   void
 123   init(Layout* layout);
 124
 125   // Add an entry to the PLT.
 126   void
 127   add_entry(Symbol_table*, Layout*, Symbol* gsym);
 128
 129   // Add an entry to the PLT for a local STT_GNU_IFUNC symbol.
 130   unsigned int
 131   add_local_ifunc_entry(Symbol_table* symtab, Layout*,
 132                         Sized_relobj_file<size, false>* relobj,
 133                         unsigned int local_sym_index);
 134
 135   // Add the relocation for a PLT entry.
 136   void
 137   add_relocation(Symbol_table*, Layout*, Symbol* gsym,
 138                  unsigned int got_offset);
 139
 140   // Add the reserved TLSDESC_PLT entry to the PLT.
 141   void
 142   reserve_tlsdesc_entry(unsigned int got_offset)
 143   { this->tlsdesc_got_offset_ = got_offset; }
 144
 145   // Return true if a TLSDESC_PLT entry has been reserved.
 146   bool
 147   has_tlsdesc_entry() const
 148   { return this->tlsdesc_got_offset_ != -1U; }
 149
 150   // Return the GOT offset for the reserved TLSDESC_PLT entry.
 151   unsigned int
 152   get_tlsdesc_got_offset() const
 153   { return this->tlsdesc_got_offset_; }
 154
 155   // Return the offset of the reserved TLSDESC_PLT entry.
 156   unsigned int
 157   get_tlsdesc_plt_offset() const
 158   {
 159     return ((this->count_ + this->irelative_count_ + 1)
 160             * this->get_plt_entry_size());
 161   }
 162
 163   // Return the .rela.plt section data.
 164   Reloc_section*
 165   rela_plt()
 166   { return this->rel_; }
 167
 168   // Return where the TLSDESC relocations should go.
 169   Reloc_section*
 170   rela_tlsdesc(Layout*);
 171
 172   // Return where the IRELATIVE relocations should go in the PLT
 173   // relocations.
 174   Reloc_section*
 175   rela_irelative(Symbol_table*, Layout*);
 176
 177   // Return whether we created a section for IRELATIVE relocations.
 178   bool
 179   has_irelative_section() const
 180   { return this->irelative_rel_ != NULL; }
 181
 182   // Get count of regular PLT entries.
 183   unsigned int
 184   regular_count() const
 185   { return this->count_; }
 186
 187   // Return the total number of PLT entries.
 188   unsigned int
 189   entry_count() const
 190   { return this->count_ + this->irelative_count_; }
 191
 192   // Return the offset of the first non-reserved PLT entry.
 193   unsigned int
 194   first_plt_entry_offset()
 195   { return this->get_plt_entry_size(); }
 196
 197   // Return the size of a PLT entry.
 198   unsigned int
 199   get_plt_entry_size() const
 200   { return this->do_get_plt_entry_size(); }
 201
 202   // Reserve a slot in the PLT for an existing symbol in an incremental update.
 203   void
 204   reserve_slot(unsigned int plt_index)
 205   {
 206     this->free_list_.remove((plt_index + 1) * this->get_plt_entry_size(),
 207                             (plt_index + 2) * this->get_plt_entry_size());
 208   }
 209
 210   // Return the PLT address to use for a global symbol.
 211   uint64_t
 212   address_for_global(const Symbol* sym)
 213   { return do_address_for_global(sym); }
 214
 215   // Return the PLT address to use for a local symbol.
 216   uint64_t
 217   address_for_local(const Relobj* obj, unsigned int symndx)
 218   { return do_address_for_local(obj, symndx); }
 219
 220   // Add .eh_frame information for the PLT.
 221   void
 222   add_eh_frame(Layout* layout)
 223   { this->do_add_eh_frame(layout); }
 224
 225  protected:
 226   Output_data_got<64, false>*
 227   got() const
 228   { return this->got_; }
 229
 230   Output_data_got_plt_x86_64*
 231   got_plt() const
 232   { return this->got_plt_; }
 233
 234   Output_data_space*
 235   got_irelative() const
 236   { return this->got_irelative_; }
 237
 238   // Fill in the first PLT entry.
 239   void
 240   fill_first_plt_entry(unsigned char* pov,
 241                        typename elfcpp::Elf_types<size>::Elf_Addr got_address,
 242                        typename elfcpp::Elf_types<size>::Elf_Addr plt_address)
 243   { this->do_fill_first_plt_entry(pov, got_address, plt_address); }
 244
 245   // Fill in a normal PLT entry.  Returns the offset into the entry that
 246   // should be the initial GOT slot value.
 247   unsigned int
 248   fill_plt_entry(unsigned char* pov,
 249                  typename elfcpp::Elf_types<size>::Elf_Addr got_address,
 250                  typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
 251                  unsigned int got_offset,
 252                  unsigned int plt_offset,
 253                  unsigned int plt_index)
 254   {
 255     return this->do_fill_plt_entry(pov, got_address, plt_address,
 256                                    got_offset, plt_offset, plt_index);
 257   }
 258
 259   // Fill in the reserved TLSDESC PLT entry.
 260   void
 261   fill_tlsdesc_entry(unsigned char* pov,
 262                      typename elfcpp::Elf_types<size>::Elf_Addr got_address,
 263                      typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
 264                      typename elfcpp::Elf_types<size>::Elf_Addr got_base,
 265                      unsigned int tlsdesc_got_offset,
 266                      unsigned int plt_offset)
 267   {
 268     this->do_fill_tlsdesc_entry(pov, got_address, plt_address, got_base,
 269                                 tlsdesc_got_offset, plt_offset);
 270   }
 271
 272   virtual unsigned int
 273   do_get_plt_entry_size() const = 0;
 274
 275   virtual void
 276   do_fill_first_plt_entry(unsigned char* pov,
 277                           typename elfcpp::Elf_types<size>::Elf_Addr got_addr,
 278                           typename elfcpp::Elf_types<size>::Elf_Addr plt_addr)
 279     = 0;
 280
 281   virtual unsigned int
 282   do_fill_plt_entry(unsigned char* pov,
 283                     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
 284                     typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
 285                     unsigned int got_offset,
 286                     unsigned int plt_offset,
 287                     unsigned int plt_index) = 0;
 288
 289   virtual void
 290   do_fill_tlsdesc_entry(unsigned char* pov,
 291                         typename elfcpp::Elf_types<size>::Elf_Addr got_address,
 292                         typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
 293                         typename elfcpp::Elf_types<size>::Elf_Addr got_base,
 294                         unsigned int tlsdesc_got_offset,
 295                         unsigned int plt_offset) = 0;
 296
 297   // Return the PLT address to use for a global symbol.
 298   virtual uint64_t
 299   do_address_for_global(const Symbol* sym);
 300
 301   // Return the PLT address to use for a local symbol.
 302   virtual uint64_t
 303   do_address_for_local(const Relobj* obj, unsigned int symndx);
 304
 305   virtual void
 306   do_add_eh_frame(Layout* layout) = 0;
 307
 308   void
 309   do_adjust_output_section(Output_section* os);
 310
 311   // Write to a map file.
 312   void
 313   do_print_to_mapfile(Mapfile* mapfile) const
 314   { mapfile->print_output_data(this, _("** PLT")); }
 315
 316   // The CIE of the .eh_frame unwind information for the PLT.
 317   static const int plt_eh_frame_cie_size = 16;
 318   static const unsigned char plt_eh_frame_cie[plt_eh_frame_cie_size];
 319
 320  private:
 321   // Set the final size.
 322   void
 323   set_final_data_size();
 324
 325   // Write out the PLT data.
 326   void
 327   do_write(Output_file*);
 328
 329   // The reloc section.
 330   Reloc_section* rel_;
 331   // The TLSDESC relocs, if necessary.  These must follow the regular
 332   // PLT relocs.
 333   Reloc_section* tlsdesc_rel_;
 334   // The IRELATIVE relocs, if necessary.  These must follow the
 335   // regular PLT relocations and the TLSDESC relocations.
 336   Reloc_section* irelative_rel_;
 337   // The .got section.
 338   Output_data_got<64, false>* got_;
 339   // The .got.plt section.
 340   Output_data_got_plt_x86_64* got_plt_;
 341   // The part of the .got.plt section used for IRELATIVE relocs.
 342   Output_data_space* got_irelative_;
 343   // The number of PLT entries.
 344   unsigned int count_;
 345   // Number of PLT entries with R_X86_64_IRELATIVE relocs.  These
 346   // follow the regular PLT entries.
 347   unsigned int irelative_count_;
 348   // Offset of the reserved TLSDESC_GOT entry when needed.
 349   unsigned int tlsdesc_got_offset_;
 350   // List of available regions within the section, for incremental
 351   // update links.
 352   Free_list free_list_;
 353 };
 354
 355 template<int size>
 356 class Output_data_plt_x86_64_standard : public Output_data_plt_x86_64<size>
 357 {
 358  public:
 359   Output_data_plt_x86_64_standard(Layout* layout,
 360                                   Output_data_got<64, false>* got,
 361                                   Output_data_got_plt_x86_64* got_plt,
 362                                   Output_data_space* got_irelative)
 363     : Output_data_plt_x86_64<size>(layout, plt_entry_size,
 364                                    got, got_plt, got_irelative)
 365   { }
 366
 367   Output_data_plt_x86_64_standard(Layout* layout,
 368                                   Output_data_got<64, false>* got,
 369                                   Output_data_got_plt_x86_64* got_plt,
 370                                   Output_data_space* got_irelative,
 371                                   unsigned int plt_count)
 372     : Output_data_plt_x86_64<size>(layout, plt_entry_size,
 373                                    got, got_plt, got_irelative,
 374                                    plt_count)
 375   { }
 376
 377  protected:
 378   virtual unsigned int
 379   do_get_plt_entry_size() const
 380   { return plt_entry_size; }
 381
 382   virtual void
 383   do_add_eh_frame(Layout* layout)
 384   {
 385     layout->add_eh_frame_for_plt(this,
 386                                  this->plt_eh_frame_cie,
 387                                  this->plt_eh_frame_cie_size,
 388                                  plt_eh_frame_fde,
 389                                  plt_eh_frame_fde_size);
 390   }
 391
 392   virtual void
 393   do_fill_first_plt_entry(unsigned char* pov,
 394                           typename elfcpp::Elf_types<size>::Elf_Addr got_addr,
 395                           typename elfcpp::Elf_types<size>::Elf_Addr plt_addr);
 396
 397   virtual unsigned int
 398   do_fill_plt_entry(unsigned char* pov,
 399                     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
 400                     typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
 401                     unsigned int got_offset,
 402                     unsigned int plt_offset,
 403                     unsigned int plt_index);
 404
 405   virtual void
 406   do_fill_tlsdesc_entry(unsigned char* pov,
 407                         typename elfcpp::Elf_types<size>::Elf_Addr got_address,
 408                         typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
 409                         typename elfcpp::Elf_types<size>::Elf_Addr got_base,
 410                         unsigned int tlsdesc_got_offset,
 411                         unsigned int plt_offset);
 412
 413  private:
 414   // The size of an entry in the PLT.
 415   static const int plt_entry_size = 16;
 416
 417   // The first entry in the PLT.
 418   // From the AMD64 ABI: "Unlike Intel386 ABI, this ABI uses the same
 419   // procedure linkage table for both programs and shared objects."
 420   static const unsigned char first_plt_entry[plt_entry_size];
 421
 422   // Other entries in the PLT for an executable.
 423   static const unsigned char plt_entry[plt_entry_size];
 424
 425   // The reserved TLSDESC entry in the PLT for an executable.
 426   static const unsigned char tlsdesc_plt_entry[plt_entry_size];
 427
 428   // The .eh_frame unwind information for the PLT.
 429   static const int plt_eh_frame_fde_size = 32;
 430   static const unsigned char plt_eh_frame_fde[plt_eh_frame_fde_size];
 431 };
 432
 433 class Output_data_plt_x86_64_bnd : public Output_data_plt_x86_64<64>
 434 {
 435  public:
 436   Output_data_plt_x86_64_bnd(Layout* layout,
 437                              Output_data_got<64, false>* got,
 438                              Output_data_got_plt_x86_64* got_plt,
 439                              Output_data_space* got_irelative)
 440     : Output_data_plt_x86_64<64>(layout, plt_entry_size,
 441                                  got, got_plt, got_irelative),
 442       aplt_offset_(0)
 443   { }
 444
 445   Output_data_plt_x86_64_bnd(Layout* layout,
 446                              Output_data_got<64, false>* got,
 447                              Output_data_got_plt_x86_64* got_plt,
 448                              Output_data_space* got_irelative,
 449                              unsigned int plt_count)
 450     : Output_data_plt_x86_64<64>(layout, plt_entry_size,
 451                                  got, got_plt, got_irelative,
 452                                  plt_count),
 453       aplt_offset_(0)
 454   { }
 455
 456  protected:
 457   virtual unsigned int
 458   do_get_plt_entry_size() const
 459   { return plt_entry_size; }
 460
 461   // Return the PLT address to use for a global symbol.
 462   uint64_t
 463   do_address_for_global(const Symbol*);
 464
 465   // Return the PLT address to use for a local symbol.
 466   uint64_t
 467   do_address_for_local(const Relobj*, unsigned int symndx);
 468
 469   virtual void
 470   do_add_eh_frame(Layout* layout)
 471   {
 472     layout->add_eh_frame_for_plt(this,
 473                                  this->plt_eh_frame_cie,
 474                                  this->plt_eh_frame_cie_size,
 475                                  plt_eh_frame_fde,
 476                                  plt_eh_frame_fde_size);
 477   }
 478
 479   virtual void
 480   do_fill_first_plt_entry(unsigned char* pov,
 481                           elfcpp::Elf_types<64>::Elf_Addr got_addr,
 482                           elfcpp::Elf_types<64>::Elf_Addr plt_addr);
 483
 484   virtual unsigned int
 485   do_fill_plt_entry(unsigned char* pov,
 486                     elfcpp::Elf_types<64>::Elf_Addr got_address,
 487                     elfcpp::Elf_types<64>::Elf_Addr plt_address,
 488                     unsigned int got_offset,
 489                     unsigned int plt_offset,
 490                     unsigned int plt_index);
 491
 492   virtual void
 493   do_fill_tlsdesc_entry(unsigned char* pov,
 494                         elfcpp::Elf_types<64>::Elf_Addr got_address,
 495                         elfcpp::Elf_types<64>::Elf_Addr plt_address,
 496                         elfcpp::Elf_types<64>::Elf_Addr got_base,
 497                         unsigned int tlsdesc_got_offset,
 498                         unsigned int plt_offset);
 499
 500   void
 501   fill_aplt_entry(unsigned char* pov,
 502                   elfcpp::Elf_types<64>::Elf_Addr got_address,
 503                   elfcpp::Elf_types<64>::Elf_Addr plt_address,
 504                   unsigned int got_offset,
 505                   unsigned int plt_offset,
 506                   unsigned int plt_index);
 507
 508  private:
 509   // Set the final size.
 510   void
 511   set_final_data_size();
 512
 513   // Write out the BND PLT data.
 514   void
 515   do_write(Output_file*);
 516
 517   // Offset of the Additional PLT (if using -z bndplt).
 518   unsigned int aplt_offset_;
 519
 520   // The size of an entry in the PLT.
 521   static const int plt_entry_size = 16;
 522
 523   // The size of an entry in the additional PLT.
 524   static const int aplt_entry_size = 8;
 525
 526   // The first entry in the PLT.
 527   // From the AMD64 ABI: "Unlike Intel386 ABI, this ABI uses the same
 528   // procedure linkage table for both programs and shared objects."
 529   static const unsigned char first_plt_entry[plt_entry_size];
 530
 531   // Other entries in the PLT for an executable.
 532   static const unsigned char plt_entry[plt_entry_size];
 533
 534   // Entries in the additional PLT.
 535   static const unsigned char aplt_entry[aplt_entry_size];
 536
 537   // The reserved TLSDESC entry in the PLT for an executable.
 538   static const unsigned char tlsdesc_plt_entry[plt_entry_size];
 539
 540   // The .eh_frame unwind information for the PLT.
 541   static const int plt_eh_frame_fde_size = 32;
 542   static const unsigned char plt_eh_frame_fde[plt_eh_frame_fde_size];
 543 };
 544
 545 // We use this PLT when Indirect Branch Tracking (IBT) is enabled.
 546
 547 template <int size>
 548 class Output_data_plt_x86_64_ibt : public Output_data_plt_x86_64<size>
 549 {
 550  public:
 551   Output_data_plt_x86_64_ibt(Layout* layout,
 552                              Output_data_got<64, false>* got,
 553                              Output_data_got_plt_x86_64* got_plt,
 554                              Output_data_space* got_irelative)
 555     : Output_data_plt_x86_64<size>(layout, plt_entry_size,
 556                                    got, got_plt, got_irelative),
 557       aplt_offset_(0)
 558   { }
 559
 560   Output_data_plt_x86_64_ibt(Layout* layout,
 561                              Output_data_got<64, false>* got,
 562                              Output_data_got_plt_x86_64* got_plt,
 563                              Output_data_space* got_irelative,
 564                              unsigned int plt_count)
 565     : Output_data_plt_x86_64<size>(layout, plt_entry_size,
 566                                    got, got_plt, got_irelative,
 567                                    plt_count),
 568       aplt_offset_(0)
 569   { }
 570
 571  protected:
 572   virtual unsigned int
 573   do_get_plt_entry_size() const
 574   { return plt_entry_size; }
 575
 576   // Return the PLT address to use for a global symbol.
 577   uint64_t
 578   do_address_for_global(const Symbol*);
 579
 580   // Return the PLT address to use for a local symbol.
 581   uint64_t
 582   do_address_for_local(const Relobj*, unsigned int symndx);
 583
 584   virtual void
 585   do_add_eh_frame(Layout* layout)
 586   {
 587     layout->add_eh_frame_for_plt(this,
 588                                  this->plt_eh_frame_cie,
 589                                  this->plt_eh_frame_cie_size,
 590                                  plt_eh_frame_fde,
 591                                  plt_eh_frame_fde_size);
 592   }
 593
 594   virtual void
 595   do_fill_first_plt_entry(unsigned char* pov,
 596                           typename elfcpp::Elf_types<size>::Elf_Addr got_addr,
 597                           typename elfcpp::Elf_types<size>::Elf_Addr plt_addr);
 598
 599   virtual unsigned int
 600   do_fill_plt_entry(unsigned char* pov,
 601                     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
 602                     typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
 603                     unsigned int got_offset,
 604                     unsigned int plt_offset,
 605                     unsigned int plt_index);
 606
 607   virtual void
 608   do_fill_tlsdesc_entry(unsigned char* pov,
 609                         typename elfcpp::Elf_types<size>::Elf_Addr got_address,
 610                         typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
 611                         typename elfcpp::Elf_types<size>::Elf_Addr got_base,
 612                         unsigned int tlsdesc_got_offset,
 613                         unsigned int plt_offset);
 614
 615   void
 616   fill_aplt_entry(unsigned char* pov,
 617                   typename elfcpp::Elf_types<size>::Elf_Addr got_address,
 618                   typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
 619                   unsigned int got_offset,
 620                   unsigned int plt_offset,
 621                   unsigned int plt_index);
 622
 623  private:
 624   // Set the final size.
 625   void
 626   set_final_data_size();
 627
 628   // Write out the BND PLT data.
 629   void
 630   do_write(Output_file*);
 631
 632   // Offset of the Additional PLT (if using -z bndplt).
 633   unsigned int aplt_offset_;
 634
 635   // The size of an entry in the PLT.
 636   static const int plt_entry_size = 16;
 637
 638   // The size of an entry in the additional PLT.
 639   static const int aplt_entry_size = 16;
 640
 641   // The first entry in the PLT.
 642   // From the AMD64 ABI: "Unlike Intel386 ABI, this ABI uses the same
 643   // procedure linkage table for both programs and shared objects."
 644   static const unsigned char first_plt_entry[plt_entry_size];
 645
 646   // Other entries in the PLT for an executable.
 647   static const unsigned char plt_entry[plt_entry_size];
 648
 649   // Entries in the additional PLT.
 650   static const unsigned char aplt_entry[aplt_entry_size];
 651
 652   // The reserved TLSDESC entry in the PLT for an executable.
 653   static const unsigned char tlsdesc_plt_entry[plt_entry_size];
 654
 655   // The .eh_frame unwind information for the PLT.
 656   static const int plt_eh_frame_fde_size = 32;
 657   static const unsigned char plt_eh_frame_fde[plt_eh_frame_fde_size];
 658 };
 659
 660 template<int size>
 661 class Lazy_view
 662 {
 663  public:
 664   Lazy_view(Sized_relobj_file<size, false>* object, unsigned int data_shndx)
 665     : object_(object), data_shndx_(data_shndx), view_(NULL), view_size_(0)
 666   { }
 667
 668   inline unsigned char
 669   operator[](size_t offset)
 670   {
 671     if (this->view_ == NULL)
 672       this->view_ = this->object_->section_contents(this->data_shndx_,
 673                                                     &this->view_size_,
 674                                                     true);
 675     if (offset >= this->view_size_)
 676       return 0;
 677     return this->view_[offset];
 678   }
 679
 680  private:
 681   Sized_relobj_file<size, false>* object_;
 682   unsigned int data_shndx_;
 683   const unsigned char* view_;
 684   section_size_type view_size_;
 685 };
 686
 687 // The x86_64 target class.
 688 // See the ABI at
 689 //   http://www.x86-64.org/documentation/abi.pdf
 690 // TLS info comes from
 691 //   http://people.redhat.com/drepper/tls.pdf
 692 //   http://www.lsd.ic.unicamp.br/~oliva/writeups/TLS/RFC-TLSDESC-x86.txt
 693
 694 template<int size>
 695 class Target_x86_64 : public Sized_target<size, false>
 696 {
 697  public:
 698   // In the x86_64 ABI (p 68), it says "The AMD64 ABI architectures
 699   // uses only Elf64_Rela relocation entries with explicit addends."
 700   typedef Output_data_reloc<elfcpp::SHT_RELA, true, size, false> Reloc_section;
 701
 702   Target_x86_64(const Target::Target_info* info = &x86_64_info)
 703     : Sized_target<size, false>(info),
 704       got_(NULL), plt_(NULL), got_plt_(NULL), got_irelative_(NULL),
 705       got_tlsdesc_(NULL), global_offset_table_(NULL), rela_dyn_(NULL),
 706       rela_irelative_(NULL), copy_relocs_(elfcpp::R_X86_64_COPY),
 707       got_mod_index_offset_(-1U), tlsdesc_reloc_info_(),
 708       tls_base_symbol_defined_(false), isa_1_used_(0), isa_1_needed_(0),
 709       feature_1_(0), object_isa_1_used_(0), object_feature_1_(0),
 710       seen_first_object_(false)
 711   { }
 712
 713   // Hook for a new output section.
 714   void
 715   do_new_output_section(Output_section*) const;
 716
 717   // Scan the relocations to look for symbol adjustments.
 718   void
 719   gc_process_relocs(Symbol_table* symtab,
 720                     Layout* layout,
 721                     Sized_relobj_file<size, false>* object,
 722                     unsigned int data_shndx,
 723                     unsigned int sh_type,
 724                     const unsigned char* prelocs,
 725                     size_t reloc_count,
 726                     Output_section* output_section,
 727                     bool needs_special_offset_handling,
 728                     size_t local_symbol_count,
 729                     const unsigned char* plocal_symbols);
 730
 731   // Scan the relocations to look for symbol adjustments.
 732   void
 733   scan_relocs(Symbol_table* symtab,
 734               Layout* layout,
 735               Sized_relobj_file<size, false>* object,
 736               unsigned int data_shndx,
 737               unsigned int sh_type,
 738               const unsigned char* prelocs,
 739               size_t reloc_count,
 740               Output_section* output_section,
 741               bool needs_special_offset_handling,
 742               size_t local_symbol_count,
 743               const unsigned char* plocal_symbols);
 744
 745   // Finalize the sections.
 746   void
 747   do_finalize_sections(Layout*, const Input_objects*, Symbol_table*);
 748
 749   // Return the value to use for a dynamic which requires special
 750   // treatment.
 751   uint64_t
 752   do_dynsym_value(const Symbol*) const;
 753
 754   // Relocate a section.
 755   void
 756   relocate_section(const Relocate_info<size, false>*,
 757                    unsigned int sh_type,
 758                    const unsigned char* prelocs,
 759                    size_t reloc_count,
 760                    Output_section* output_section,
 761                    bool needs_special_offset_handling,
 762                    unsigned char* view,
 763                    typename elfcpp::Elf_types<size>::Elf_Addr view_address,
 764                    section_size_type view_size,
 765                    const Reloc_symbol_changes*);
 766
 767   // Scan the relocs during a relocatable link.
 768   void
 769   scan_relocatable_relocs(Symbol_table* symtab,
 770                           Layout* layout,
 771                           Sized_relobj_file<size, false>* object,
 772                           unsigned int data_shndx,
 773                           unsigned int sh_type,
 774                           const unsigned char* prelocs,
 775                           size_t reloc_count,
 776                           Output_section* output_section,
 777                           bool needs_special_offset_handling,
 778                           size_t local_symbol_count,
 779                           const unsigned char* plocal_symbols,
 780                           Relocatable_relocs*);
 781
 782   // Scan the relocs for --emit-relocs.
 783   void
 784   emit_relocs_scan(Symbol_table* symtab,
 785                    Layout* layout,
 786                    Sized_relobj_file<size, false>* object,
 787                    unsigned int data_shndx,
 788                    unsigned int sh_type,
 789                    const unsigned char* prelocs,
 790                    size_t reloc_count,
 791                    Output_section* output_section,
 792                    bool needs_special_offset_handling,
 793                    size_t local_symbol_count,
 794                    const unsigned char* plocal_syms,
 795                    Relocatable_relocs* rr);
 796
 797   // Emit relocations for a section.
 798   void
 799   relocate_relocs(
 800       const Relocate_info<size, false>*,
 801       unsigned int sh_type,
 802       const unsigned char* prelocs,
 803       size_t reloc_count,
 804       Output_section* output_section,
 805       typename elfcpp::Elf_types<size>::Elf_Off offset_in_output_section,
 806       unsigned char* view,
 807       typename elfcpp::Elf_types<size>::Elf_Addr view_address,
 808       section_size_type view_size,
 809       unsigned char* reloc_view,
 810       section_size_type reloc_view_size);
 811
 812   // Return a string used to fill a code section with nops.
 813   std::string
 814   do_code_fill(section_size_type length) const;
 815
 816   // Return whether SYM is defined by the ABI.
 817   bool
 818   do_is_defined_by_abi(const Symbol* sym) const
 819   { return strcmp(sym->name(), "__tls_get_addr") == 0; }
 820
 821   // Return the symbol index to use for a target specific relocation.
 822   // The only target specific relocation is R_X86_64_TLSDESC for a
 823   // local symbol, which is an absolute reloc.
 824   unsigned int
 825   do_reloc_symbol_index(void*, unsigned int r_type) const
 826   {
 827     gold_assert(r_type == elfcpp::R_X86_64_TLSDESC);
 828     return 0;
 829   }
 830
 831   // Return the addend to use for a target specific relocation.
 832   uint64_t
 833   do_reloc_addend(void* arg, unsigned int r_type, uint64_t addend) const;
 834
 835   // Return the PLT section.
 836   uint64_t
 837   do_plt_address_for_global(const Symbol* gsym) const
 838   { return this->plt_section()->address_for_global(gsym); }
 839
 840   uint64_t
 841   do_plt_address_for_local(const Relobj* relobj, unsigned int symndx) const
 842   { return this->plt_section()->address_for_local(relobj, symndx); }
 843
 844   // This function should be defined in targets that can use relocation
 845   // types to determine (implemented in local_reloc_may_be_function_pointer
 846   // and global_reloc_may_be_function_pointer)
 847   // if a function's pointer is taken.  ICF uses this in safe mode to only
 848   // fold those functions whose pointer is defintely not taken.  For x86_64
 849   // pie binaries, safe ICF cannot be done by looking at only relocation
 850   // types, and for certain cases (e.g. R_X86_64_PC32), the instruction
 851   // opcode is checked as well to distinguish a function call from taking
 852   // a function's pointer.
 853   bool
 854   do_can_check_for_function_pointers() const
 855   { return true; }
 856
 857   // Return the base for a DW_EH_PE_datarel encoding.
 858   uint64_t
 859   do_ehframe_datarel_base() const;
 860
 861   // Adjust -fsplit-stack code which calls non-split-stack code.
 862   void
 863   do_calls_non_split(Relobj* object, unsigned int shndx,
 864                      section_offset_type fnoffset, section_size_type fnsize,
 865                      const unsigned char* prelocs, size_t reloc_count,
 866                      unsigned char* view, section_size_type view_size,
 867                      std::string* from, std::string* to) const;
 868
 869   // Return the size of the GOT section.
 870   section_size_type
 871   got_size() const
 872   {
 873     gold_assert(this->got_ != NULL);
 874     return this->got_->data_size();
 875   }
 876
 877   // Return the number of entries in the GOT.
 878   unsigned int
 879   got_entry_count() const
 880   {
 881     if (this->got_ == NULL)
 882       return 0;
 883     return this->got_size() / 8;
 884   }
 885
 886   // Return the number of entries in the PLT.
 887   unsigned int
 888   plt_entry_count() const;
 889
 890   // Return the offset of the first non-reserved PLT entry.
 891   unsigned int
 892   first_plt_entry_offset() const;
 893
 894   // Return the size of each PLT entry.
 895   unsigned int
 896   plt_entry_size() const;
 897
 898   // Return the size of each GOT entry.
 899   unsigned int
 900   got_entry_size() const
 901   { return 8; };
 902
 903   // Create the GOT section for an incremental update.
 904   Output_data_got_base*
 905   init_got_plt_for_update(Symbol_table* symtab,
 906                           Layout* layout,
 907                           unsigned int got_count,
 908                           unsigned int plt_count);
 909
 910   // Reserve a GOT entry for a local symbol, and regenerate any
 911   // necessary dynamic relocations.
 912   void
 913   reserve_local_got_entry(unsigned int got_index,
 914                           Sized_relobj<size, false>* obj,
 915                           unsigned int r_sym,
 916                           unsigned int got_type);
 917
 918   // Reserve a GOT entry for a global symbol, and regenerate any
 919   // necessary dynamic relocations.
 920   void
 921   reserve_global_got_entry(unsigned int got_index, Symbol* gsym,
 922                            unsigned int got_type);
 923
 924   // Register an existing PLT entry for a global symbol.
 925   void
 926   register_global_plt_entry(Symbol_table*, Layout*, unsigned int plt_index,
 927                             Symbol* gsym);
 928
 929   // Force a COPY relocation for a given symbol.
 930   void
 931   emit_copy_reloc(Symbol_table*, Symbol*, Output_section*, off_t);
 932
 933   // Apply an incremental relocation.
 934   void
 935   apply_relocation(const Relocate_info<size, false>* relinfo,
 936                    typename elfcpp::Elf_types<size>::Elf_Addr r_offset,
 937                    unsigned int r_type,
 938                    typename elfcpp::Elf_types<size>::Elf_Swxword r_addend,
 939                    const Symbol* gsym,
 940                    unsigned char* view,
 941                    typename elfcpp::Elf_types<size>::Elf_Addr address,
 942                    section_size_type view_size);
 943
 944   // Add a new reloc argument, returning the index in the vector.
 945   size_t
 946   add_tlsdesc_info(Sized_relobj_file<size, false>* object, unsigned int r_sym)
 947   {
 948     this->tlsdesc_reloc_info_.push_back(Tlsdesc_info(object, r_sym));
 949     return this->tlsdesc_reloc_info_.size() - 1;
 950   }
 951
 952   Output_data_plt_x86_64<size>*
 953   make_data_plt(Layout* layout,
 954                 Output_data_got<64, false>* got,
 955                 Output_data_got_plt_x86_64* got_plt,
 956                 Output_data_space* got_irelative)
 957   {
 958     return this->do_make_data_plt(layout, got, got_plt, got_irelative);
 959   }
 960
 961   Output_data_plt_x86_64<size>*
 962   make_data_plt(Layout* layout,
 963                 Output_data_got<64, false>* got,
 964                 Output_data_got_plt_x86_64* got_plt,
 965                 Output_data_space* got_irelative,
 966                 unsigned int plt_count)
 967   {
 968     return this->do_make_data_plt(layout, got, got_plt, got_irelative,
 969                                   plt_count);
 970   }
 971
 972   virtual Output_data_plt_x86_64<size>*
 973   do_make_data_plt(Layout* layout,
 974                    Output_data_got<64, false>* got,
 975                    Output_data_got_plt_x86_64* got_plt,
 976                    Output_data_space* got_irelative);
 977
 978   virtual Output_data_plt_x86_64<size>*
 979   do_make_data_plt(Layout* layout,
 980                    Output_data_got<64, false>* got,
 981                    Output_data_got_plt_x86_64* got_plt,
 982                    Output_data_space* got_irelative,
 983                    unsigned int plt_count);
 984
 985  private:
 986   // The class which scans relocations.
 987   class Scan
 988   {
 989   public:
 990     Scan()
 991       : issued_non_pic_error_(false)
 992     { }
 993
 994     static inline int
 995     get_reference_flags(unsigned int r_type);
 996
 997     inline void
 998     local(Symbol_table* symtab, Layout* layout, Target_x86_64* target,
 999           Sized_relobj_file<size, false>* object,
1000           unsigned int data_shndx,
1001           Output_section* output_section,
1002           const elfcpp::Rela<size, false>& reloc, unsigned int r_type,
1003           const elfcpp::Sym<size, false>& lsym,
1004           bool is_discarded);
1005
1006     inline void
1007     global(Symbol_table* symtab, Layout* layout, Target_x86_64* target,
1008            Sized_relobj_file<size, false>* object,
1009            unsigned int data_shndx,
1010            Output_section* output_section,
1011            const elfcpp::Rela<size, false>& reloc, unsigned int r_type,
1012            Symbol* gsym);
1013
1014     inline bool
1015     local_reloc_may_be_function_pointer(Symbol_table* symtab, Layout* layout,
1016                                         Target_x86_64* target,
1017                                         Sized_relobj_file<size, false>* object,
1018                                         unsigned int data_shndx,
1019                                         Output_section* output_section,
1020                                         const elfcpp::Rela<size, false>& reloc,
1021                                         unsigned int r_type,
1022                                         const elfcpp::Sym<size, false>& lsym);
1023
1024     inline bool
1025     global_reloc_may_be_function_pointer(Symbol_table* symtab, Layout* layout,
1026                                          Target_x86_64* target,
1027                                          Sized_relobj_file<size, false>* object,
1028                                          unsigned int data_shndx,
1029                                          Output_section* output_section,
1030                                          const elfcpp::Rela<size, false>& reloc,
1031                                          unsigned int r_type,
1032                                          Symbol* gsym);
1033
1034   private:
1035     static void
1036     unsupported_reloc_local(Sized_relobj_file<size, false>*,
1037                             unsigned int r_type);
1038
1039     static void
1040     unsupported_reloc_global(Sized_relobj_file<size, false>*,
1041                              unsigned int r_type, Symbol*);
1042
1043     void
1044     check_non_pic(Relobj*, unsigned int r_type, Symbol*);
1045
1046     inline bool
1047     possible_function_pointer_reloc(Sized_relobj_file<size, false>* src_obj,
1048                                     unsigned int src_indx,
1049                                     unsigned int r_offset,
1050                                     unsigned int r_type);
1051
1052     bool
1053     reloc_needs_plt_for_ifunc(Sized_relobj_file<size, false>*,
1054                               unsigned int r_type);
1055
1056     // Whether we have issued an error about a non-PIC compilation.
1057     bool issued_non_pic_error_;
1058   };
1059
1060   // The class which implements relocation.
1061   class Relocate
1062   {
1063    public:
1064     Relocate()
1065       : skip_call_tls_get_addr_(false)
1066     { }
1067
1068     ~Relocate()
1069     {
1070       if (this->skip_call_tls_get_addr_)
1071         {
1072           // FIXME: This needs to specify the location somehow.
1073           gold_error(_("missing expected TLS relocation"));
1074         }
1075     }
1076
1077     // Do a relocation.  Return false if the caller should not issue
1078     // any warnings about this relocation.
1079     inline bool
1080     relocate(const Relocate_info<size, false>*, unsigned int,
1081              Target_x86_64*, Output_section*, size_t, const unsigned char*,
1082              const Sized_symbol<size>*, const Symbol_value<size>*,
1083              unsigned char*, typename elfcpp::Elf_types<size>::Elf_Addr,
1084              section_size_type);
1085
1086    private:
1087     // Do a TLS relocation.
1088     inline void
1089     relocate_tls(const Relocate_info<size, false>*, Target_x86_64*,
1090                  size_t relnum, const elfcpp::Rela<size, false>&,
1091                  unsigned int r_type, const Sized_symbol<size>*,
1092                  const Symbol_value<size>*,
1093                  unsigned char*, typename elfcpp::Elf_types<size>::Elf_Addr,
1094                  section_size_type);
1095
1096     // Do a TLS General-Dynamic to Initial-Exec transition.
1097     inline void
1098     tls_gd_to_ie(const Relocate_info<size, false>*, size_t relnum,
1099                  const elfcpp::Rela<size, false>&, unsigned int r_type,
1100                  typename elfcpp::Elf_types<size>::Elf_Addr value,
1101                  unsigned char* view,
1102                  typename elfcpp::Elf_types<size>::Elf_Addr,
1103                  section_size_type view_size);
1104
1105     // Do a TLS General-Dynamic to Local-Exec transition.
1106     inline void
1107     tls_gd_to_le(const Relocate_info<size, false>*, size_t relnum,
1108                  Output_segment* tls_segment,
1109                  const elfcpp::Rela<size, false>&, unsigned int r_type,
1110                  typename elfcpp::Elf_types<size>::Elf_Addr value,
1111                  unsigned char* view,
1112                  section_size_type view_size);
1113
1114     // Do a TLSDESC-style General-Dynamic to Initial-Exec transition.
1115     inline void
1116     tls_desc_gd_to_ie(const Relocate_info<size, false>*, size_t relnum,
1117                       const elfcpp::Rela<size, false>&, unsigned int r_type,
1118                       typename elfcpp::Elf_types<size>::Elf_Addr value,
1119                       unsigned char* view,
1120                       typename elfcpp::Elf_types<size>::Elf_Addr,
1121                       section_size_type view_size);
1122
1123     // Do a TLSDESC-style General-Dynamic to Local-Exec transition.
1124     inline void
1125     tls_desc_gd_to_le(const Relocate_info<size, false>*, size_t relnum,
1126                       Output_segment* tls_segment,
1127                       const elfcpp::Rela<size, false>&, unsigned int r_type,
1128                       typename elfcpp::Elf_types<size>::Elf_Addr value,
1129                       unsigned char* view,
1130                       section_size_type view_size);
1131
1132     // Do a TLS Local-Dynamic to Local-Exec transition.
1133     inline void
1134     tls_ld_to_le(const Relocate_info<size, false>*, size_t relnum,
1135                  Output_segment* tls_segment,
1136                  const elfcpp::Rela<size, false>&, unsigned int r_type,
1137                  typename elfcpp::Elf_types<size>::Elf_Addr value,
1138                  unsigned char* view,
1139                  section_size_type view_size);
1140
1141     // Do a TLS Initial-Exec to Local-Exec transition.
1142     static inline void
1143     tls_ie_to_le(const Relocate_info<size, false>*, size_t relnum,
1144                  Output_segment* tls_segment,
1145                  const elfcpp::Rela<size, false>&, unsigned int r_type,
1146                  typename elfcpp::Elf_types<size>::Elf_Addr value,
1147                  unsigned char* view,
1148                  section_size_type view_size);
1149
1150     // This is set if we should skip the next reloc, which should be a
1151     // PLT32 reloc against ___tls_get_addr.
1152     bool skip_call_tls_get_addr_;
1153   };
1154
1155   // Check if relocation against this symbol is a candidate for
1156   // conversion from
1157   // mov foo@GOTPCREL(%rip), %reg
1158   // to lea foo(%rip), %reg.
1159   template<class View_type>
1160   static inline bool
1161   can_convert_mov_to_lea(const Symbol* gsym, unsigned int r_type,
1162                          size_t r_offset, View_type* view)
1163   {
1164     gold_assert(gsym != NULL);
1165     // We cannot do the conversion unless it's one of these relocations.
1166     if (r_type != elfcpp::R_X86_64_GOTPCREL
1167         && r_type != elfcpp::R_X86_64_GOTPCRELX
1168         && r_type != elfcpp::R_X86_64_REX_GOTPCRELX)
1169       return false;
1170     // We cannot convert references to IFUNC symbols, or to symbols that
1171     // are not local to the current module.
1172     // We can't do predefined symbols because they may become undefined
1173     // (e.g., __ehdr_start when the headers aren't mapped to a segment).
1174     if (gsym->type() == elfcpp::STT_GNU_IFUNC
1175         || gsym->is_undefined()
1176         || gsym->is_predefined()
1177         || gsym->is_from_dynobj()
1178         || gsym->is_preemptible())
1179       return false;
1180     // If we are building a shared object and the symbol is protected, we may
1181     // need to go through the GOT.
1182     if (parameters->options().shared()
1183         && gsym->visibility() == elfcpp::STV_PROTECTED)
1184       return false;
1185     // We cannot convert references to the _DYNAMIC symbol.
1186     if (strcmp(gsym->name(), "_DYNAMIC") == 0)
1187       return false;
1188     // Check for a MOV opcode.
1189     return (*view)[r_offset - 2] == 0x8b;
1190   }
1191
1192   // Convert
1193   // callq *foo@GOTPCRELX(%rip) to
1194   // addr32 callq foo
1195   // and jmpq *foo@GOTPCRELX(%rip) to
1196   // jmpq foo
1197   // nop
1198   template<class View_type>
1199   static inline bool
1200   can_convert_callq_to_direct(const Symbol* gsym, unsigned int r_type,
1201                               size_t r_offset, View_type* view)
1202   {
1203     gold_assert(gsym != NULL);
1204     // We cannot do the conversion unless it's a GOTPCRELX relocation.
1205     if (r_type != elfcpp::R_X86_64_GOTPCRELX)
1206       return false;
1207     // We cannot convert references to IFUNC symbols, or to symbols that
1208     // are not local to the current module.
1209     if (gsym->type() == elfcpp::STT_GNU_IFUNC
1210         || gsym->is_undefined ()
1211         || gsym->is_from_dynobj()
1212         || gsym->is_preemptible())
1213       return false;
1214     // Check for a CALLQ or JMPQ opcode.
1215     return ((*view)[r_offset - 2] == 0xff
1216             && ((*view)[r_offset - 1] == 0x15
1217                 || (*view)[r_offset - 1] == 0x25));
1218   }
1219
1220   // Adjust TLS relocation type based on the options and whether this
1221   // is a local symbol.
1222   static tls::Tls_optimization
1223   optimize_tls_reloc(bool is_final, int r_type);
1224
1225   // Get the GOT section, creating it if necessary.
1226   Output_data_got<64, false>*
1227   got_section(Symbol_table*, Layout*);
1228
1229   // Get the GOT PLT section.
1230   Output_data_got_plt_x86_64*
1231   got_plt_section() const
1232   {
1233     gold_assert(this->got_plt_ != NULL);
1234     return this->got_plt_;
1235   }
1236
1237   // Get the GOT section for TLSDESC entries.
1238   Output_data_got<64, false>*
1239   got_tlsdesc_section() const
1240   {
1241     gold_assert(this->got_tlsdesc_ != NULL);
1242     return this->got_tlsdesc_;
1243   }
1244
1245   // Create the PLT section.
1246   void
1247   make_plt_section(Symbol_table* symtab, Layout* layout);
1248
1249   // Create a PLT entry for a global symbol.
1250   void
1251   make_plt_entry(Symbol_table*, Layout*, Symbol*);
1252
1253   // Create a PLT entry for a local STT_GNU_IFUNC symbol.
1254   void
1255   make_local_ifunc_plt_entry(Symbol_table*, Layout*,
1256                              Sized_relobj_file<size, false>* relobj,
1257                              unsigned int local_sym_index);
1258
1259   // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
1260   void
1261   define_tls_base_symbol(Symbol_table*, Layout*);
1262
1263   // Create the reserved PLT and GOT entries for the TLS descriptor resolver.
1264   void
1265   reserve_tlsdesc_entries(Symbol_table* symtab, Layout* layout);
1266
1267   // Create a GOT entry for the TLS module index.
1268   unsigned int
1269   got_mod_index_entry(Symbol_table* symtab, Layout* layout,
1270                       Sized_relobj_file<size, false>* object);
1271
1272   // Get the PLT section.
1273   Output_data_plt_x86_64<size>*
1274   plt_section() const
1275   {
1276     gold_assert(this->plt_ != NULL);
1277     return this->plt_;
1278   }
1279
1280   // Get the dynamic reloc section, creating it if necessary.
1281   Reloc_section*
1282   rela_dyn_section(Layout*);
1283
1284   // Get the section to use for TLSDESC relocations.
1285   Reloc_section*
1286   rela_tlsdesc_section(Layout*) const;
1287
1288   // Get the section to use for IRELATIVE relocations.
1289   Reloc_section*
1290   rela_irelative_section(Layout*);
1291
1292   // Add a potential copy relocation.
1293   void
1294   copy_reloc(Symbol_table* symtab, Layout* layout,
1295              Sized_relobj_file<size, false>* object,
1296              unsigned int shndx, Output_section* output_section,
1297              Symbol* sym, const elfcpp::Rela<size, false>& reloc)
1298   {
1299     unsigned int r_type = elfcpp::elf_r_type<size>(reloc.get_r_info());
1300     this->copy_relocs_.copy_reloc(symtab, layout,
1301                                   symtab->get_sized_symbol<size>(sym),
1302                                   object, shndx, output_section,
1303                                   r_type, reloc.get_r_offset(),
1304                                   reloc.get_r_addend(),
1305                                   this->rela_dyn_section(layout));
1306   }
1307
1308   // Record a target-specific program property in the .note.gnu.property
1309   // section.
1310   void
1311   record_gnu_property(unsigned int, unsigned int, size_t,
1312                       const unsigned char*, const Object*);
1313
1314   // Merge the target-specific program properties from the current object.
1315   void
1316   merge_gnu_properties(const Object*);
1317
1318   // Finalize the target-specific program properties and add them back to
1319   // the layout.
1320   void
1321   do_finalize_gnu_properties(Layout*) const;
1322
1323   // Information about this specific target which we pass to the
1324   // general Target structure.
1325   static const Target::Target_info x86_64_info;
1326
1327   // The types of GOT entries needed for this platform.
1328   // These values are exposed to the ABI in an incremental link.
1329   // Do not renumber existing values without changing the version
1330   // number of the .gnu_incremental_inputs section.
1331   enum Got_type
1332   {
1333     GOT_TYPE_STANDARD = 0,      // GOT entry for a regular symbol
1334     GOT_TYPE_TLS_OFFSET = 1,    // GOT entry for TLS offset
1335     GOT_TYPE_TLS_PAIR = 2,      // GOT entry for TLS module/offset pair
1336     GOT_TYPE_TLS_DESC = 3       // GOT entry for TLS_DESC pair
1337   };
1338
1339   // This type is used as the argument to the target specific
1340   // relocation routines.  The only target specific reloc is
1341   // R_X86_64_TLSDESC against a local symbol.
1342   struct Tlsdesc_info
1343   {
1344     Tlsdesc_info(Sized_relobj_file<size, false>* a_object, unsigned int a_r_sym)
1345       : object(a_object), r_sym(a_r_sym)
1346     { }
1347
1348     // The object in which the local symbol is defined.
1349     Sized_relobj_file<size, false>* object;
1350     // The local symbol index in the object.
1351     unsigned int r_sym;
1352   };
1353
1354   // The GOT section.
1355   Output_data_got<64, false>* got_;
1356   // The PLT section.
1357   Output_data_plt_x86_64<size>* plt_;
1358   // The GOT PLT section.
1359   Output_data_got_plt_x86_64* got_plt_;
1360   // The GOT section for IRELATIVE relocations.
1361   Output_data_space* got_irelative_;
1362   // The GOT section for TLSDESC relocations.
1363   Output_data_got<64, false>* got_tlsdesc_;
1364   // The _GLOBAL_OFFSET_TABLE_ symbol.
1365   Symbol* global_offset_table_;
1366   // The dynamic reloc section.
1367   Reloc_section* rela_dyn_;
1368   // The section to use for IRELATIVE relocs.
1369   Reloc_section* rela_irelative_;
1370   // Relocs saved to avoid a COPY reloc.
1371   Copy_relocs<elfcpp::SHT_RELA, size, false> copy_relocs_;
1372   // Offset of the GOT entry for the TLS module index.
1373   unsigned int got_mod_index_offset_;
1374   // We handle R_X86_64_TLSDESC against a local symbol as a target
1375   // specific relocation.  Here we store the object and local symbol
1376   // index for the relocation.
1377   std::vector<Tlsdesc_info> tlsdesc_reloc_info_;
1378   // True if the _TLS_MODULE_BASE_ symbol has been defined.
1379   bool tls_base_symbol_defined_;
1380   // Target-specific program properties, from .note.gnu.property section.
1381   // Each bit represents a specific feature.
1382   uint32_t isa_1_used_;
1383   uint32_t isa_1_needed_;
1384   uint32_t feature_1_;
1385   // Target-specific properties from the current object.
1386   // These bits get ORed into ISA_1_USED_ after all properties for the object
1387   // have been processed. But if either is all zeroes (as when the property
1388   // is absent from an object), the result should be all zeroes.
1389   // (See PR ld/23486.)
1390   uint32_t object_isa_1_used_;
1391   // These bits get ANDed into FEATURE_1_ after all properties for the object
1392   // have been processed.
1393   uint32_t object_feature_1_;
1394   // Whether we have seen our first object, for use in initializing FEATURE_1_.
1395   bool seen_first_object_;
1396 };
1397
1398 template<>
1399 const Target::Target_info Target_x86_64<64>::x86_64_info =
1400 {
1401   64,                   // size
1402   false,                // is_big_endian
1403   elfcpp::EM_X86_64,    // machine_code
1404   false,                // has_make_symbol
1405   false,                // has_resolve
1406   true,                 // has_code_fill
1407   true,                 // is_default_stack_executable
1408   true,                 // can_icf_inline_merge_sections
1409   '\0',                 // wrap_char
1410   "/lib/ld64.so.1",     // program interpreter
1411   0x400000,             // default_text_segment_address
1412   0x1000,               // abi_pagesize (overridable by -z max-page-size)
1413   0x1000,               // common_pagesize (overridable by -z common-page-size)
1414   false,                // isolate_execinstr
1415   0,                    // rosegment_gap
1416   elfcpp::SHN_UNDEF,    // small_common_shndx
1417   elfcpp::SHN_X86_64_LCOMMON,   // large_common_shndx
1418   0,                    // small_common_section_flags
1419   elfcpp::SHF_X86_64_LARGE,     // large_common_section_flags
1420   NULL,                 // attributes_section
1421   NULL,                 // attributes_vendor
1422   "_start",             // entry_symbol_name
1423   32,                   // hash_entry_size
1424   elfcpp::SHT_X86_64_UNWIND,    // unwind_section_type
1425 };
1426
1427 template<>
1428 const Target::Target_info Target_x86_64<32>::x86_64_info =
1429 {
1430   32,                   // size
1431   false,                // is_big_endian
1432   elfcpp::EM_X86_64,    // machine_code
1433   false,                // has_make_symbol
1434   false,                // has_resolve
1435   true,                 // has_code_fill
1436   true,                 // is_default_stack_executable
1437   true,                 // can_icf_inline_merge_sections
1438   '\0',                 // wrap_char
1439   "/libx32/ldx32.so.1", // program interpreter
1440   0x400000,             // default_text_segment_address
1441   0x1000,               // abi_pagesize (overridable by -z max-page-size)
1442   0x1000,               // common_pagesize (overridable by -z common-page-size)
1443   false,                // isolate_execinstr
1444   0,                    // rosegment_gap
1445   elfcpp::SHN_UNDEF,    // small_common_shndx
1446   elfcpp::SHN_X86_64_LCOMMON,   // large_common_shndx
1447   0,                    // small_common_section_flags
1448   elfcpp::SHF_X86_64_LARGE,     // large_common_section_flags
1449   NULL,                 // attributes_section
1450   NULL,                 // attributes_vendor
1451   "_start",             // entry_symbol_name
1452   32,                   // hash_entry_size
1453   elfcpp::SHT_X86_64_UNWIND,    // unwind_section_type
1454 };
1455
1456 // This is called when a new output section is created.  This is where
1457 // we handle the SHF_X86_64_LARGE.
1458
1459 template<int size>
1460 void
1461 Target_x86_64<size>::do_new_output_section(Output_section* os) const
1462 {
1463   if ((os->flags() & elfcpp::SHF_X86_64_LARGE) != 0)
1464     os->set_is_large_section();
1465 }
1466
1467 // Get the GOT section, creating it if necessary.
1468
1469 template<int size>
1470 Output_data_got<64, false>*
1471 Target_x86_64<size>::got_section(Symbol_table* symtab, Layout* layout)
1472 {
1473   if (this->got_ == NULL)
1474     {
1475       gold_assert(symtab != NULL && layout != NULL);
1476
1477       // When using -z now, we can treat .got.plt as a relro section.
1478       // Without -z now, it is modified after program startup by lazy
1479       // PLT relocations.
1480       bool is_got_plt_relro = parameters->options().now();
1481       Output_section_order got_order = (is_got_plt_relro
1482                                         ? ORDER_RELRO
1483                                         : ORDER_RELRO_LAST);
1484       Output_section_order got_plt_order = (is_got_plt_relro
1485                                             ? ORDER_RELRO
1486                                             : ORDER_NON_RELRO_FIRST);
1487
1488       this->got_ = new Output_data_got<64, false>();
1489
1490       layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
1491                                       (elfcpp::SHF_ALLOC
1492                                        | elfcpp::SHF_WRITE),
1493                                       this->got_, got_order, true);
1494
1495       this->got_plt_ = new Output_data_got_plt_x86_64(layout);
1496       layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
1497                                       (elfcpp::SHF_ALLOC
1498                                        | elfcpp::SHF_WRITE),
1499                                       this->got_plt_, got_plt_order,
1500                                       is_got_plt_relro);
1501
1502       // The first three entries are reserved.
1503       this->got_plt_->set_current_data_size(3 * 8);
1504
1505       if (!is_got_plt_relro)
1506         {
1507           // Those bytes can go into the relro segment.
1508           layout->increase_relro(3 * 8);
1509         }
1510
1511       // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
1512       this->global_offset_table_ =
1513         symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
1514                                       Symbol_table::PREDEFINED,
1515                                       this->got_plt_,
1516                                       0, 0, elfcpp::STT_OBJECT,
1517                                       elfcpp::STB_LOCAL,
1518                                       elfcpp::STV_HIDDEN, 0,
1519                                       false, false);
1520
1521       // If there are any IRELATIVE relocations, they get GOT entries
1522       // in .got.plt after the jump slot entries.
1523       this->got_irelative_ = new Output_data_space(8, "** GOT IRELATIVE PLT");
1524       layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
1525                                       (elfcpp::SHF_ALLOC
1526                                        | elfcpp::SHF_WRITE),
1527                                       this->got_irelative_,
1528                                       got_plt_order, is_got_plt_relro);
1529
1530       // If there are any TLSDESC relocations, they get GOT entries in
1531       // .got.plt after the jump slot and IRELATIVE entries.
1532       this->got_tlsdesc_ = new Output_data_got<64, false>();
1533       layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
1534                                       (elfcpp::SHF_ALLOC
1535                                        | elfcpp::SHF_WRITE),
1536                                       this->got_tlsdesc_,
1537                                       got_plt_order, is_got_plt_relro);
1538     }
1539
1540   return this->got_;
1541 }
1542
1543 // Get the dynamic reloc section, creating it if necessary.
1544
1545 template<int size>
1546 typename Target_x86_64<size>::Reloc_section*
1547 Target_x86_64<size>::rela_dyn_section(Layout* layout)
1548 {
1549   if (this->rela_dyn_ == NULL)
1550     {
1551       gold_assert(layout != NULL);
1552       this->rela_dyn_ = new Reloc_section(parameters->options().combreloc());
1553       layout->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA,
1554                                       elfcpp::SHF_ALLOC, this->rela_dyn_,
1555                                       ORDER_DYNAMIC_RELOCS, false);
1556     }
1557   return this->rela_dyn_;
1558 }
1559
1560 // Get the section to use for IRELATIVE relocs, creating it if
1561 // necessary.  These go in .rela.dyn, but only after all other dynamic
1562 // relocations.  They need to follow the other dynamic relocations so
1563 // that they can refer to global variables initialized by those
1564 // relocs.
1565
1566 template<int size>
1567 typename Target_x86_64<size>::Reloc_section*
1568 Target_x86_64<size>::rela_irelative_section(Layout* layout)
1569 {
1570   if (this->rela_irelative_ == NULL)
1571     {
1572       // Make sure we have already created the dynamic reloc section.
1573       this->rela_dyn_section(layout);
1574       this->rela_irelative_ = new Reloc_section(false);
1575       layout->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA,
1576                                       elfcpp::SHF_ALLOC, this->rela_irelative_,
1577                                       ORDER_DYNAMIC_RELOCS, false);
1578       gold_assert(this->rela_dyn_->output_section()
1579                   == this->rela_irelative_->output_section());
1580     }
1581   return this->rela_irelative_;
1582 }
1583
1584 // Record a target-specific program property from the .note.gnu.property
1585 // section.
1586 template<int size>
1587 void
1588 Target_x86_64<size>::record_gnu_property(
1589     unsigned int, unsigned int pr_type,
1590     size_t pr_datasz, const unsigned char* pr_data,
1591     const Object* object)
1592 {
1593   uint32_t val = 0;
1594
1595   switch (pr_type)
1596     {
1597     case elfcpp::GNU_PROPERTY_X86_ISA_1_USED:
1598     case elfcpp::GNU_PROPERTY_X86_ISA_1_NEEDED:
1599     case elfcpp::GNU_PROPERTY_X86_FEATURE_1_AND:
1600       if (pr_datasz != 4)
1601         {
1602           gold_warning(_("%s: corrupt .note.gnu.property section "
1603                          "(pr_datasz for property %d is not 4)"),
1604                        object->name().c_str(), pr_type);
1605           return;
1606         }
1607       val = elfcpp::Swap<32, false>::readval(pr_data);
1608       break;
1609     default:
1610       gold_warning(_("%s: unknown program property type 0x%x "
1611                      "in .note.gnu.property section"),
1612                    object->name().c_str(), pr_type);
1613       break;
1614     }
1615
1616   switch (pr_type)
1617     {
1618     case elfcpp::GNU_PROPERTY_X86_ISA_1_USED:
1619       this->object_isa_1_used_ |= val;
1620       break;
1621     case elfcpp::GNU_PROPERTY_X86_ISA_1_NEEDED:
1622       this->isa_1_needed_ |= val;
1623       break;
1624     case elfcpp::GNU_PROPERTY_X86_FEATURE_1_AND:
1625       // If we see multiple feature props in one object, OR them together.
1626       this->object_feature_1_ |= val;
1627       break;
1628     }
1629 }
1630
1631 // Merge the target-specific program properties from the current object.
1632 template<int size>
1633 void
1634 Target_x86_64<size>::merge_gnu_properties(const Object*)
1635 {
1636   if (this->seen_first_object_)
1637     {
1638       // If any object is missing the ISA_1_USED property, we must omit
1639       // it from the output file.
1640       if (this->object_isa_1_used_ == 0)
1641         this->isa_1_used_ = 0;
1642       else if (this->isa_1_used_ != 0)
1643         this->isa_1_used_ |= this->object_isa_1_used_;
1644       this->feature_1_ &= this->object_feature_1_;
1645     }
1646   else
1647     {
1648       this->isa_1_used_ = this->object_isa_1_used_;
1649       this->feature_1_ = this->object_feature_1_;
1650       this->seen_first_object_ = true;
1651     }
1652   this->object_isa_1_used_ = 0;
1653   this->object_feature_1_ = 0;
1654 }
1655
1656 static inline void
1657 add_property(Layout* layout, unsigned int pr_type, uint32_t val)
1658 {
1659   unsigned char buf[4];
1660   elfcpp::Swap<32, false>::writeval(buf, val);
1661   layout->add_gnu_property(elfcpp::NT_GNU_PROPERTY_TYPE_0, pr_type, 4, buf);
1662 }
1663
1664 // Finalize the target-specific program properties and add them back to
1665 // the layout.
1666 template<int size>
1667 void
1668 Target_x86_64<size>::do_finalize_gnu_properties(Layout* layout) const
1669 {
1670   if (this->isa_1_used_ != 0)
1671     add_property(layout, elfcpp::GNU_PROPERTY_X86_ISA_1_USED,
1672                  this->isa_1_used_);
1673   if (this->isa_1_needed_ != 0)
1674     add_property(layout, elfcpp::GNU_PROPERTY_X86_ISA_1_NEEDED,
1675                  this->isa_1_needed_);
1676   if (this->feature_1_ != 0)
1677     add_property(layout, elfcpp::GNU_PROPERTY_X86_FEATURE_1_AND,
1678                  this->feature_1_);
1679 }
1680
1681 // Write the first three reserved words of the .got.plt section.
1682 // The remainder of the section is written while writing the PLT
1683 // in Output_data_plt_i386::do_write.
1684
1685 void
1686 Output_data_got_plt_x86_64::do_write(Output_file* of)
1687 {
1688   // The first entry in the GOT is the address of the .dynamic section
1689   // aka the PT_DYNAMIC segment.  The next two entries are reserved.
1690   // We saved space for them when we created the section in
1691   // Target_x86_64::got_section.
1692   const off_t got_file_offset = this->offset();
1693   gold_assert(this->data_size() >= 24);
1694   unsigned char* const got_view = of->get_output_view(got_file_offset, 24);
1695   Output_section* dynamic = this->layout_->dynamic_section();
1696   uint64_t dynamic_addr = dynamic == NULL ? 0 : dynamic->address();
1697   elfcpp::Swap<64, false>::writeval(got_view, dynamic_addr);
1698   memset(got_view + 8, 0, 16);
1699   of->write_output_view(got_file_offset, 24, got_view);
1700 }
1701
1702 // Initialize the PLT section.
1703
1704 template<int size>
1705 void
1706 Output_data_plt_x86_64<size>::init(Layout* layout)
1707 {
1708   this->rel_ = new Reloc_section(false);
1709   layout->add_output_section_data(".rela.plt", elfcpp::SHT_RELA,
1710                                   elfcpp::SHF_ALLOC, this->rel_,
1711                                   ORDER_DYNAMIC_PLT_RELOCS, false);
1712 }
1713
1714 template<int size>
1715 void
1716 Output_data_plt_x86_64<size>::do_adjust_output_section(Output_section* os)
1717 {
1718   os->set_entsize(this->get_plt_entry_size());
1719 }
1720
1721 // Add an entry to the PLT.
1722
1723 template<int size>
1724 void
1725 Output_data_plt_x86_64<size>::add_entry(Symbol_table* symtab, Layout* layout,
1726                                         Symbol* gsym)
1727 {
1728   gold_assert(!gsym->has_plt_offset());
1729
1730   unsigned int plt_index;
1731   off_t plt_offset;
1732   section_offset_type got_offset;
1733
1734   unsigned int* pcount;
1735   unsigned int offset;
1736   unsigned int reserved;
1737   Output_section_data_build* got;
1738   if (gsym->type() == elfcpp::STT_GNU_IFUNC
1739       && gsym->can_use_relative_reloc(false))
1740     {
1741       pcount = &this->irelative_count_;
1742       offset = 0;
1743       reserved = 0;
1744       got = this->got_irelative_;
1745     }
1746   else
1747     {
1748       pcount = &this->count_;
1749       offset = 1;
1750       reserved = 3;
1751       got = this->got_plt_;
1752     }
1753
1754   if (!this->is_data_size_valid())
1755     {
1756       // Note that when setting the PLT offset for a non-IRELATIVE
1757       // entry we skip the initial reserved PLT entry.
1758       plt_index = *pcount + offset;
1759       plt_offset = plt_index * this->get_plt_entry_size();
1760
1761       ++*pcount;
1762
1763       got_offset = (plt_index - offset + reserved) * 8;
1764       gold_assert(got_offset == got->current_data_size());
1765
1766       // Every PLT entry needs a GOT entry which points back to the PLT
1767       // entry (this will be changed by the dynamic linker, normally
1768       // lazily when the function is called).
1769       got->set_current_data_size(got_offset + 8);
1770     }
1771   else
1772     {
1773       // FIXME: This is probably not correct for IRELATIVE relocs.
1774
1775       // For incremental updates, find an available slot.
1776       plt_offset = this->free_list_.allocate(this->get_plt_entry_size(),
1777                                              this->get_plt_entry_size(), 0);
1778       if (plt_offset == -1)
1779         gold_fallback(_("out of patch space (PLT);"
1780                         " relink with --incremental-full"));
1781
1782       // The GOT and PLT entries have a 1-1 correspondance, so the GOT offset
1783       // can be calculated from the PLT index, adjusting for the three
1784       // reserved entries at the beginning of the GOT.
1785       plt_index = plt_offset / this->get_plt_entry_size() - 1;
1786       got_offset = (plt_index - offset + reserved) * 8;
1787     }
1788
1789   gsym->set_plt_offset(plt_offset);
1790
1791   // Every PLT entry needs a reloc.
1792   this->add_relocation(symtab, layout, gsym, got_offset);
1793
1794   // Note that we don't need to save the symbol.  The contents of the
1795   // PLT are independent of which symbols are used.  The symbols only
1796   // appear in the relocations.
1797 }
1798
1799 // Add an entry to the PLT for a local STT_GNU_IFUNC symbol.  Return
1800 // the PLT offset.
1801
1802 template<int size>
1803 unsigned int
1804 Output_data_plt_x86_64<size>::add_local_ifunc_entry(
1805     Symbol_table* symtab,
1806     Layout* layout,
1807     Sized_relobj_file<size, false>* relobj,
1808     unsigned int local_sym_index)
1809 {
1810   unsigned int plt_offset = this->irelative_count_ * this->get_plt_entry_size();
1811   ++this->irelative_count_;
1812
1813   section_offset_type got_offset = this->got_irelative_->current_data_size();
1814
1815   // Every PLT entry needs a GOT entry which points back to the PLT
1816   // entry.
1817   this->got_irelative_->set_current_data_size(got_offset + 8);
1818
1819   // Every PLT entry needs a reloc.
1820   Reloc_section* rela = this->rela_irelative(symtab, layout);
1821   rela->add_symbolless_local_addend(relobj, local_sym_index,
1822                                     elfcpp::R_X86_64_IRELATIVE,
1823                                     this->got_irelative_, got_offset, 0);
1824
1825   return plt_offset;
1826 }
1827
1828 // Add the relocation for a PLT entry.
1829
1830 template<int size>
1831 void
1832 Output_data_plt_x86_64<size>::add_relocation(Symbol_table* symtab,
1833                                              Layout* layout,
1834                                              Symbol* gsym,
1835                                              unsigned int got_offset)
1836 {
1837   if (gsym->type() == elfcpp::STT_GNU_IFUNC
1838       && gsym->can_use_relative_reloc(false))
1839     {
1840       Reloc_section* rela = this->rela_irelative(symtab, layout);
1841       rela->add_symbolless_global_addend(gsym, elfcpp::R_X86_64_IRELATIVE,
1842                                          this->got_irelative_, got_offset, 0);
1843     }
1844   else
1845     {
1846       gsym->set_needs_dynsym_entry();
1847       this->rel_->add_global(gsym, elfcpp::R_X86_64_JUMP_SLOT, this->got_plt_,
1848                              got_offset, 0);
1849     }
1850 }
1851
1852 // Return where the TLSDESC relocations should go, creating it if
1853 // necessary.  These follow the JUMP_SLOT relocations.
1854
1855 template<int size>
1856 typename Output_data_plt_x86_64<size>::Reloc_section*
1857 Output_data_plt_x86_64<size>::rela_tlsdesc(Layout* layout)
1858 {
1859   if (this->tlsdesc_rel_ == NULL)
1860     {
1861       this->tlsdesc_rel_ = new Reloc_section(false);
1862       layout->add_output_section_data(".rela.plt", elfcpp::SHT_RELA,
1863                                       elfcpp::SHF_ALLOC, this->tlsdesc_rel_,
1864                                       ORDER_DYNAMIC_PLT_RELOCS, false);
1865       gold_assert(this->tlsdesc_rel_->output_section()
1866                   == this->rel_->output_section());
1867     }
1868   return this->tlsdesc_rel_;
1869 }
1870
1871 // Return where the IRELATIVE relocations should go in the PLT.  These
1872 // follow the JUMP_SLOT and the TLSDESC relocations.
1873
1874 template<int size>
1875 typename Output_data_plt_x86_64<size>::Reloc_section*
1876 Output_data_plt_x86_64<size>::rela_irelative(Symbol_table* symtab,
1877                                              Layout* layout)
1878 {
1879   if (this->irelative_rel_ == NULL)
1880     {
1881       // Make sure we have a place for the TLSDESC relocations, in
1882       // case we see any later on.
1883       this->rela_tlsdesc(layout);
1884       this->irelative_rel_ = new Reloc_section(false);
1885       layout->add_output_section_data(".rela.plt", elfcpp::SHT_RELA,
1886                                       elfcpp::SHF_ALLOC, this->irelative_rel_,
1887                                       ORDER_DYNAMIC_PLT_RELOCS, false);
1888       gold_assert(this->irelative_rel_->output_section()
1889                   == this->rel_->output_section());
1890
1891       if (parameters->doing_static_link())
1892         {
1893           // A statically linked executable will only have a .rela.plt
1894           // section to hold R_X86_64_IRELATIVE relocs for
1895           // STT_GNU_IFUNC symbols.  The library will use these
1896           // symbols to locate the IRELATIVE relocs at program startup
1897           // time.
1898           symtab->define_in_output_data("__rela_iplt_start", NULL,
1899                                         Symbol_table::PREDEFINED,
1900                                         this->irelative_rel_, 0, 0,
1901                                         elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL,
1902                                         elfcpp::STV_HIDDEN, 0, false, true);
1903           symtab->define_in_output_data("__rela_iplt_end", NULL,
1904                                         Symbol_table::PREDEFINED,
1905                                         this->irelative_rel_, 0, 0,
1906                                         elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL,
1907                                         elfcpp::STV_HIDDEN, 0, true, true);
1908         }
1909     }
1910   return this->irelative_rel_;
1911 }
1912
1913 // Return the PLT address to use for a global symbol.
1914
1915 template<int size>
1916 uint64_t
1917 Output_data_plt_x86_64<size>::do_address_for_global(const Symbol* gsym)
1918 {
1919   uint64_t offset = 0;
1920   if (gsym->type() == elfcpp::STT_GNU_IFUNC
1921       && gsym->can_use_relative_reloc(false))
1922     offset = (this->count_ + 1) * this->get_plt_entry_size();
1923   return this->address() + offset + gsym->plt_offset();
1924 }
1925
1926 // Return the PLT address to use for a local symbol.  These are always
1927 // IRELATIVE relocs.
1928
1929 template<int size>
1930 uint64_t
1931 Output_data_plt_x86_64<size>::do_address_for_local(const Relobj* object,
1932                                                    unsigned int r_sym)
1933 {
1934   return (this->address()
1935           + (this->count_ + 1) * this->get_plt_entry_size()
1936           + object->local_plt_offset(r_sym));
1937 }
1938
1939 // Set the final size.
1940 template<int size>
1941 void
1942 Output_data_plt_x86_64<size>::set_final_data_size()
1943 {
1944   // Number of regular and IFUNC PLT entries, plus the first entry.
1945   unsigned int count = this->count_ + this->irelative_count_ + 1;
1946   // Count the TLSDESC entry, if present.
1947   if (this->has_tlsdesc_entry())
1948     ++count;
1949   this->set_data_size(count * this->get_plt_entry_size());
1950 }
1951
1952 // The first entry in the PLT for an executable.
1953
1954 template<int size>
1955 const unsigned char
1956 Output_data_plt_x86_64_standard<size>::first_plt_entry[plt_entry_size] =
1957 {
1958   // From AMD64 ABI Draft 0.98, page 76
1959   0xff, 0x35,   // pushq contents of memory address
1960   0, 0, 0, 0,   // replaced with address of .got + 8
1961   0xff, 0x25,   // jmp indirect
1962   0, 0, 0, 0,   // replaced with address of .got + 16
1963   0x90, 0x90, 0x90, 0x90   // noop (x4)
1964 };
1965
1966 template<int size>
1967 void
1968 Output_data_plt_x86_64_standard<size>::do_fill_first_plt_entry(
1969     unsigned char* pov,
1970     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
1971     typename elfcpp::Elf_types<size>::Elf_Addr plt_address)
1972 {
1973   memcpy(pov, first_plt_entry, plt_entry_size);
1974   // We do a jmp relative to the PC at the end of this instruction.
1975   elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
1976                                               (got_address + 8
1977                                                - (plt_address + 6)));
1978   elfcpp::Swap<32, false>::writeval(pov + 8,
1979                                     (got_address + 16
1980                                      - (plt_address + 12)));
1981 }
1982
1983 // Subsequent entries in the PLT for an executable.
1984
1985 template<int size>
1986 const unsigned char
1987 Output_data_plt_x86_64_standard<size>::plt_entry[plt_entry_size] =
1988 {
1989   // From AMD64 ABI Draft 0.98, page 76
1990   0xff, 0x25,   // jmpq indirect
1991   0, 0, 0, 0,   // replaced with address of symbol in .got
1992   0x68,         // pushq immediate
1993   0, 0, 0, 0,   // replaced with offset into relocation table
1994   0xe9,         // jmpq relative
1995   0, 0, 0, 0    // replaced with offset to start of .plt
1996 };
1997
1998 template<int size>
1999 unsigned int
2000 Output_data_plt_x86_64_standard<size>::do_fill_plt_entry(
2001     unsigned char* pov,
2002     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
2003     typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
2004     unsigned int got_offset,
2005     unsigned int plt_offset,
2006     unsigned int plt_index)
2007 {
2008   // Check PC-relative offset overflow in PLT entry.
2009   uint64_t plt_got_pcrel_offset = (got_address + got_offset
2010                                    - (plt_address + plt_offset + 6));
2011   if (Bits<32>::has_overflow(plt_got_pcrel_offset))
2012     gold_error(_("PC-relative offset overflow in PLT entry %d"),
2013                plt_index + 1);
2014
2015   memcpy(pov, plt_entry, plt_entry_size);
2016   elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
2017                                               plt_got_pcrel_offset);
2018
2019   elfcpp::Swap_unaligned<32, false>::writeval(pov + 7, plt_index);
2020   elfcpp::Swap<32, false>::writeval(pov + 12,
2021                                     - (plt_offset + plt_entry_size));
2022
2023   return 6;
2024 }
2025
2026 // The reserved TLSDESC entry in the PLT for an executable.
2027
2028 template<int size>
2029 const unsigned char
2030 Output_data_plt_x86_64_standard<size>::tlsdesc_plt_entry[plt_entry_size] =
2031 {
2032   // From Alexandre Oliva, "Thread-Local Storage Descriptors for IA32
2033   // and AMD64/EM64T", Version 0.9.4 (2005-10-10).
2034   0xff, 0x35,   // pushq x(%rip)
2035   0, 0, 0, 0,   // replaced with address of linkmap GOT entry (at PLTGOT + 8)
2036   0xff, 0x25,   // jmpq *y(%rip)
2037   0, 0, 0, 0,   // replaced with offset of reserved TLSDESC_GOT entry
2038   0x0f, 0x1f,   // nop
2039   0x40, 0
2040 };
2041
2042 template<int size>
2043 void
2044 Output_data_plt_x86_64_standard<size>::do_fill_tlsdesc_entry(
2045     unsigned char* pov,
2046     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
2047     typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
2048     typename elfcpp::Elf_types<size>::Elf_Addr got_base,
2049     unsigned int tlsdesc_got_offset,
2050     unsigned int plt_offset)
2051 {
2052   memcpy(pov, tlsdesc_plt_entry, plt_entry_size);
2053   elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
2054                                               (got_address + 8
2055                                                - (plt_address + plt_offset
2056                                                   + 6)));
2057   elfcpp::Swap_unaligned<32, false>::writeval(pov + 8,
2058                                               (got_base
2059                                                + tlsdesc_got_offset
2060                                                - (plt_address + plt_offset
2061                                                   + 12)));
2062 }
2063
2064 // Return the APLT address to use for a global symbol (for -z bndplt).
2065
2066 uint64_t
2067 Output_data_plt_x86_64_bnd::do_address_for_global(const Symbol* gsym)
2068 {
2069   uint64_t offset = this->aplt_offset_;
2070   // Convert the PLT offset into an APLT offset.
2071   unsigned int plt_offset = gsym->plt_offset();
2072   if (gsym->type() == elfcpp::STT_GNU_IFUNC
2073       && gsym->can_use_relative_reloc(false))
2074     offset += this->regular_count() * aplt_entry_size;
2075   else
2076     plt_offset -= plt_entry_size;
2077   plt_offset = plt_offset / (plt_entry_size / aplt_entry_size);
2078   return this->address() + offset + plt_offset;
2079 }
2080
2081 // Return the PLT address to use for a local symbol.  These are always
2082 // IRELATIVE relocs.
2083
2084 uint64_t
2085 Output_data_plt_x86_64_bnd::do_address_for_local(const Relobj* object,
2086                                                  unsigned int r_sym)
2087 {
2088   // Convert the PLT offset into an APLT offset.
2089   unsigned int plt_offset = ((object->local_plt_offset(r_sym) - plt_entry_size)
2090                              / (plt_entry_size / aplt_entry_size));
2091   return (this->address()
2092           + this->aplt_offset_
2093           + this->regular_count() * aplt_entry_size
2094           + plt_offset);
2095 }
2096
2097 // Set the final size.
2098 void
2099 Output_data_plt_x86_64_bnd::set_final_data_size()
2100 {
2101   // Number of regular and IFUNC PLT entries.
2102   unsigned int count = this->entry_count();
2103   // Count the first entry and the TLSDESC entry, if present.
2104   unsigned int extra = this->has_tlsdesc_entry() ? 2 : 1;
2105   unsigned int plt_size = (count + extra) * plt_entry_size;
2106   // Offset of the APLT.
2107   this->aplt_offset_ = plt_size;
2108   // Size of the APLT.
2109   plt_size += count * aplt_entry_size;
2110   this->set_data_size(plt_size);
2111 }
2112
2113 // The first entry in the BND PLT.
2114
2115 const unsigned char
2116 Output_data_plt_x86_64_bnd::first_plt_entry[plt_entry_size] =
2117 {
2118   // From AMD64 ABI Draft 0.98, page 76
2119   0xff, 0x35,           // pushq contents of memory address
2120   0, 0, 0, 0,           // replaced with address of .got + 8
2121   0xf2, 0xff, 0x25,     // bnd jmp indirect
2122   0, 0, 0, 0,           // replaced with address of .got + 16
2123   0x0f, 0x1f, 0x00      // nop
2124 };
2125
2126 void
2127 Output_data_plt_x86_64_bnd::do_fill_first_plt_entry(
2128     unsigned char* pov,
2129     elfcpp::Elf_types<64>::Elf_Addr got_address,
2130     elfcpp::Elf_types<64>::Elf_Addr plt_address)
2131 {
2132   memcpy(pov, first_plt_entry, plt_entry_size);
2133   // We do a jmp relative to the PC at the end of this instruction.
2134   elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
2135                                               (got_address + 8
2136                                                - (plt_address + 6)));
2137   elfcpp::Swap<32, false>::writeval(pov + 9,
2138                                     (got_address + 16
2139                                      - (plt_address + 13)));
2140 }
2141
2142 // Subsequent entries in the BND PLT.
2143
2144 const unsigned char
2145 Output_data_plt_x86_64_bnd::plt_entry[plt_entry_size] =
2146 {
2147   // From AMD64 ABI Draft 0.99.8, page 139
2148   0x68,                         // pushq immediate
2149   0, 0, 0, 0,                   // replaced with offset into relocation table
2150   0xf2, 0xe9,                   // bnd jmpq relative
2151   0, 0, 0, 0,                   // replaced with offset to start of .plt
2152   0x0f, 0x1f, 0x44, 0, 0        // nop
2153 };
2154
2155 // Entries in the BND Additional PLT.
2156
2157 const unsigned char
2158 Output_data_plt_x86_64_bnd::aplt_entry[aplt_entry_size] =
2159 {
2160   // From AMD64 ABI Draft 0.99.8, page 139
2161   0xf2, 0xff, 0x25,     // bnd jmpq indirect
2162   0, 0, 0, 0,           // replaced with address of symbol in .got
2163   0x90,                 // nop
2164 };
2165
2166 unsigned int
2167 Output_data_plt_x86_64_bnd::do_fill_plt_entry(
2168     unsigned char* pov,
2169     elfcpp::Elf_types<64>::Elf_Addr,
2170     elfcpp::Elf_types<64>::Elf_Addr,
2171     unsigned int,
2172     unsigned int plt_offset,
2173     unsigned int plt_index)
2174 {
2175   memcpy(pov, plt_entry, plt_entry_size);
2176   elfcpp::Swap_unaligned<32, false>::writeval(pov + 1, plt_index);
2177   elfcpp::Swap<32, false>::writeval(pov + 7, -(plt_offset + 11));
2178   return 0;
2179 }
2180
2181 void
2182 Output_data_plt_x86_64_bnd::fill_aplt_entry(
2183     unsigned char* pov,
2184     elfcpp::Elf_types<64>::Elf_Addr got_address,
2185     elfcpp::Elf_types<64>::Elf_Addr plt_address,
2186     unsigned int got_offset,
2187     unsigned int plt_offset,
2188     unsigned int plt_index)
2189 {
2190   // Check PC-relative offset overflow in PLT entry.
2191   uint64_t plt_got_pcrel_offset = (got_address + got_offset
2192                                    - (plt_address + plt_offset + 7));
2193   if (Bits<32>::has_overflow(plt_got_pcrel_offset))
2194     gold_error(_("PC-relative offset overflow in APLT entry %d"),
2195                plt_index + 1);
2196
2197   memcpy(pov, aplt_entry, aplt_entry_size);
2198   elfcpp::Swap_unaligned<32, false>::writeval(pov + 3, plt_got_pcrel_offset);
2199 }
2200
2201 // The reserved TLSDESC entry in the PLT for an executable.
2202
2203 const unsigned char
2204 Output_data_plt_x86_64_bnd::tlsdesc_plt_entry[plt_entry_size] =
2205 {
2206   // From Alexandre Oliva, "Thread-Local Storage Descriptors for IA32
2207   // and AMD64/EM64T", Version 0.9.4 (2005-10-10).
2208   0xff, 0x35,           // pushq x(%rip)
2209   0, 0, 0, 0,           // replaced with address of linkmap GOT entry (at PLTGOT + 8)
2210   0xf2, 0xff, 0x25,     // jmpq *y(%rip)
2211   0, 0, 0, 0,           // replaced with offset of reserved TLSDESC_GOT entry
2212   0x0f, 0x1f, 0         // nop
2213 };
2214
2215 void
2216 Output_data_plt_x86_64_bnd::do_fill_tlsdesc_entry(
2217     unsigned char* pov,
2218     elfcpp::Elf_types<64>::Elf_Addr got_address,
2219     elfcpp::Elf_types<64>::Elf_Addr plt_address,
2220     elfcpp::Elf_types<64>::Elf_Addr got_base,
2221     unsigned int tlsdesc_got_offset,
2222     unsigned int plt_offset)
2223 {
2224   memcpy(pov, tlsdesc_plt_entry, plt_entry_size);
2225   elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
2226                                               (got_address + 8
2227                                                - (plt_address + plt_offset
2228                                                   + 6)));
2229   elfcpp::Swap_unaligned<32, false>::writeval(pov + 9,
2230                                               (got_base
2231                                                + tlsdesc_got_offset
2232                                                - (plt_address + plt_offset
2233                                                   + 13)));
2234 }
2235
2236 // Return the APLT address to use for a global symbol (for IBT).
2237
2238 template<int size>
2239 uint64_t
2240 Output_data_plt_x86_64_ibt<size>::do_address_for_global(const Symbol* gsym)
2241 {
2242   uint64_t offset = this->aplt_offset_;
2243   // Convert the PLT offset into an APLT offset.
2244   unsigned int plt_offset = gsym->plt_offset();
2245   if (gsym->type() == elfcpp::STT_GNU_IFUNC
2246       && gsym->can_use_relative_reloc(false))
2247     offset += this->regular_count() * aplt_entry_size;
2248   else
2249     plt_offset -= plt_entry_size;
2250   plt_offset = plt_offset / (plt_entry_size / aplt_entry_size);
2251   return this->address() + offset + plt_offset;
2252 }
2253
2254 // Return the PLT address to use for a local symbol.  These are always
2255 // IRELATIVE relocs.
2256
2257 template<int size>
2258 uint64_t
2259 Output_data_plt_x86_64_ibt<size>::do_address_for_local(const Relobj* object,
2260                                                  unsigned int r_sym)
2261 {
2262   // Convert the PLT offset into an APLT offset.
2263   unsigned int plt_offset = ((object->local_plt_offset(r_sym) - plt_entry_size)
2264                              / (plt_entry_size / aplt_entry_size));
2265   return (this->address()
2266           + this->aplt_offset_
2267           + this->regular_count() * aplt_entry_size
2268           + plt_offset);
2269 }
2270
2271 // Set the final size.
2272
2273 template<int size>
2274 void
2275 Output_data_plt_x86_64_ibt<size>::set_final_data_size()
2276 {
2277   // Number of regular and IFUNC PLT entries.
2278   unsigned int count = this->entry_count();
2279   // Count the first entry and the TLSDESC entry, if present.
2280   unsigned int extra = this->has_tlsdesc_entry() ? 2 : 1;
2281   unsigned int plt_size = (count + extra) * plt_entry_size;
2282   // Offset of the APLT.
2283   this->aplt_offset_ = plt_size;
2284   // Size of the APLT.
2285   plt_size += count * aplt_entry_size;
2286   this->set_data_size(plt_size);
2287 }
2288
2289 // The first entry in the IBT PLT.
2290
2291 template<>
2292 const unsigned char
2293 Output_data_plt_x86_64_ibt<32>::first_plt_entry[plt_entry_size] =
2294 {
2295   // MPX isn't supported for x32, so we don't need the BND prefix.
2296   // From AMD64 ABI Draft 0.98, page 76
2297   0xff, 0x35,            // pushq contents of memory address
2298   0, 0, 0, 0,            // replaced with address of .got + 8
2299   0xff, 0x25,            // jmp indirect
2300   0, 0, 0, 0,            // replaced with address of .got + 16
2301   0x90, 0x90, 0x90, 0x90 // noop (x4)
2302 };
2303
2304 template<>
2305 const unsigned char
2306 Output_data_plt_x86_64_ibt<64>::first_plt_entry[plt_entry_size] =
2307 {
2308   // Use the BND prefix so that IBT is compatible with MPX.
2309   0xff, 0x35,           // pushq contents of memory address
2310   0, 0, 0, 0,           // replaced with address of .got + 8
2311   0xf2, 0xff, 0x25,     // bnd jmp indirect
2312   0, 0, 0, 0,           // replaced with address of .got + 16
2313   0x0f, 0x1f, 0x00      // nop
2314 };
2315
2316 template<int size>
2317 void
2318 Output_data_plt_x86_64_ibt<size>::do_fill_first_plt_entry(
2319     unsigned char* pov,
2320     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
2321     typename elfcpp::Elf_types<size>::Elf_Addr plt_address)
2322 {
2323   // Offsets to the addresses needing relocation.
2324   const unsigned int roff1 = 2;
2325   const unsigned int roff2 = (size == 32) ? 8 : 9;
2326
2327   memcpy(pov, first_plt_entry, plt_entry_size);
2328   // We do a jmp relative to the PC at the end of this instruction.
2329   elfcpp::Swap_unaligned<32, false>::writeval(pov + roff1,
2330                                               (got_address + 8
2331                                                - (plt_address + roff1 + 4)));
2332   elfcpp::Swap<32, false>::writeval(pov + roff2,
2333                                     (got_address + 16
2334                                      - (plt_address + roff2 + 4)));
2335 }
2336
2337 // Subsequent entries in the IBT PLT.
2338
2339 template<>
2340 const unsigned char
2341 Output_data_plt_x86_64_ibt<32>::plt_entry[plt_entry_size] =
2342 {
2343   // From AMD64 ABI Draft 1.0-rc1, Chapter 13.
2344   0xf3, 0x0f, 0x1e, 0xfa,       // endbr64
2345   0x68,                         // pushq immediate
2346   0, 0, 0, 0,                   // replaced with offset into relocation table
2347   0xe9,                         // jmpq relative
2348   0, 0, 0, 0,                   // replaced with offset to start of .plt
2349   0x90, 0x90                    // nop
2350 };
2351
2352 template<>
2353 const unsigned char
2354 Output_data_plt_x86_64_ibt<64>::plt_entry[plt_entry_size] =
2355 {
2356   // From AMD64 ABI Draft 1.0-rc1, Chapter 13.
2357   0xf3, 0x0f, 0x1e, 0xfa,       // endbr64
2358   0x68,                         // pushq immediate
2359   0, 0, 0, 0,                   // replaced with offset into relocation table
2360   0xf2, 0xe9,                   // bnd jmpq relative
2361   0, 0, 0, 0,                   // replaced with offset to start of .plt
2362   0x90                          // nop
2363 };
2364
2365 // Entries in the IBT Additional PLT.
2366
2367 template<>
2368 const unsigned char
2369 Output_data_plt_x86_64_ibt<32>::aplt_entry[aplt_entry_size] =
2370 {
2371   // From AMD64 ABI Draft 1.0-rc1, Chapter 13.
2372   0xf3, 0x0f, 0x1e, 0xfa,       // endbr64
2373   0xff, 0x25,                   // jmpq indirect
2374   0, 0, 0, 0,                   // replaced with address of symbol in .got
2375   0x0f, 0x1f, 0x04, 0x00,       // nop
2376   0x90, 0x90                    // nop
2377 };
2378
2379 template<>
2380 const unsigned char
2381 Output_data_plt_x86_64_ibt<64>::aplt_entry[aplt_entry_size] =
2382 {
2383   // From AMD64 ABI Draft 1.0-rc1, Chapter 13.
2384   0xf3, 0x0f, 0x1e, 0xfa,       // endbr64
2385   0xf2, 0xff, 0x25,             // bnd jmpq indirect
2386   0, 0, 0, 0,                   // replaced with address of symbol in .got
2387   0x0f, 0x1f, 0x04, 0x00,       // nop
2388   0x90,                         // nop
2389 };
2390
2391 template<int size>
2392 unsigned int
2393 Output_data_plt_x86_64_ibt<size>::do_fill_plt_entry(
2394     unsigned char* pov,
2395     typename elfcpp::Elf_types<size>::Elf_Addr,
2396     typename elfcpp::Elf_types<size>::Elf_Addr,
2397     unsigned int,
2398     unsigned int plt_offset,
2399     unsigned int plt_index)
2400 {
2401   // Offsets to the addresses needing relocation.
2402   const unsigned int roff1 = 5;
2403   const unsigned int roff2 = (size == 32) ? 10 : 11;
2404
2405   memcpy(pov, plt_entry, plt_entry_size);
2406   elfcpp::Swap_unaligned<32, false>::writeval(pov + roff1, plt_index);
2407   elfcpp::Swap<32, false>::writeval(pov + roff2, -(plt_offset + roff2 + 4));
2408   return 0;
2409 }
2410
2411 template<int size>
2412 void
2413 Output_data_plt_x86_64_ibt<size>::fill_aplt_entry(
2414     unsigned char* pov,
2415     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
2416     typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
2417     unsigned int got_offset,
2418     unsigned int plt_offset,
2419     unsigned int plt_index)
2420 {
2421   // Offset to the address needing relocation.
2422   const unsigned int roff = (size == 32) ? 6 : 7;
2423
2424   // Check PC-relative offset overflow in PLT entry.
2425   uint64_t plt_got_pcrel_offset = (got_address + got_offset
2426                                    - (plt_address + plt_offset + roff + 4));
2427   if (Bits<32>::has_overflow(plt_got_pcrel_offset))
2428     gold_error(_("PC-relative offset overflow in APLT entry %d"),
2429                plt_index + 1);
2430
2431   memcpy(pov, aplt_entry, aplt_entry_size);
2432   elfcpp::Swap_unaligned<32, false>::writeval(pov + roff, plt_got_pcrel_offset);
2433 }
2434
2435 // The reserved TLSDESC entry in the IBT PLT for an executable.
2436
2437 template<int size>
2438 const unsigned char
2439 Output_data_plt_x86_64_ibt<size>::tlsdesc_plt_entry[plt_entry_size] =
2440 {
2441   // From Alexandre Oliva, "Thread-Local Storage Descriptors for IA32
2442   // and AMD64/EM64T", Version 0.9.4 (2005-10-10).
2443   0xff, 0x35,           // pushq x(%rip)
2444   0, 0, 0, 0,           // replaced with address of linkmap GOT entry (at PLTGOT + 8)
2445   0xf2, 0xff, 0x25,     // jmpq *y(%rip)
2446   0, 0, 0, 0,           // replaced with offset of reserved TLSDESC_GOT entry
2447   0x0f, 0x1f, 0         // nop
2448 };
2449
2450 template<int size>
2451 void
2452 Output_data_plt_x86_64_ibt<size>::do_fill_tlsdesc_entry(
2453     unsigned char* pov,
2454     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
2455     typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
2456     typename elfcpp::Elf_types<size>::Elf_Addr got_base,
2457     unsigned int tlsdesc_got_offset,
2458     unsigned int plt_offset)
2459 {
2460   memcpy(pov, tlsdesc_plt_entry, plt_entry_size);
2461   elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
2462                                               (got_address + 8
2463                                                - (plt_address + plt_offset
2464                                                   + 6)));
2465   elfcpp::Swap_unaligned<32, false>::writeval(pov + 9,
2466                                               (got_base
2467                                                + tlsdesc_got_offset
2468                                                - (plt_address + plt_offset
2469                                                   + 13)));
2470 }
2471
2472 // The .eh_frame unwind information for the PLT.
2473
2474 template<int size>
2475 const unsigned char
2476 Output_data_plt_x86_64<size>::plt_eh_frame_cie[plt_eh_frame_cie_size] =
2477 {
2478   1,                            // CIE version.
2479   'z',                          // Augmentation: augmentation size included.
2480   'R',                          // Augmentation: FDE encoding included.
2481   '\0',                         // End of augmentation string.
2482   1,                            // Code alignment factor.
2483   0x78,                         // Data alignment factor.
2484   16,                           // Return address column.
2485   1,                            // Augmentation size.
2486   (elfcpp::DW_EH_PE_pcrel       // FDE encoding.
2487    | elfcpp::DW_EH_PE_sdata4),
2488   elfcpp::DW_CFA_def_cfa, 7, 8, // DW_CFA_def_cfa: r7 (rsp) ofs 8.
2489   elfcpp::DW_CFA_offset + 16, 1,// DW_CFA_offset: r16 (rip) at cfa-8.
2490   elfcpp::DW_CFA_nop,           // Align to 16 bytes.
2491   elfcpp::DW_CFA_nop
2492 };
2493
2494 template<int size>
2495 const unsigned char
2496 Output_data_plt_x86_64_standard<size>::plt_eh_frame_fde[plt_eh_frame_fde_size] =
2497 {
2498   0, 0, 0, 0,                           // Replaced with offset to .plt.
2499   0, 0, 0, 0,                           // Replaced with size of .plt.
2500   0,                                    // Augmentation size.
2501   elfcpp::DW_CFA_def_cfa_offset, 16,    // DW_CFA_def_cfa_offset: 16.
2502   elfcpp::DW_CFA_advance_loc + 6,       // Advance 6 to __PLT__ + 6.
2503   elfcpp::DW_CFA_def_cfa_offset, 24,    // DW_CFA_def_cfa_offset: 24.
2504   elfcpp::DW_CFA_advance_loc + 10,      // Advance 10 to __PLT__ + 16.
2505   elfcpp::DW_CFA_def_cfa_expression,    // DW_CFA_def_cfa_expression.
2506   11,                                   // Block length.
2507   elfcpp::DW_OP_breg7, 8,               // Push %rsp + 8.
2508   elfcpp::DW_OP_breg16, 0,              // Push %rip.
2509   elfcpp::DW_OP_lit15,                  // Push 0xf.
2510   elfcpp::DW_OP_and,                    // & (%rip & 0xf).
2511   elfcpp::DW_OP_lit11,                  // Push 0xb.
2512   elfcpp::DW_OP_ge,                     // >= ((%rip & 0xf) >= 0xb)
2513   elfcpp::DW_OP_lit3,                   // Push 3.
2514   elfcpp::DW_OP_shl,                    // << (((%rip & 0xf) >= 0xb) << 3)
2515   elfcpp::DW_OP_plus,                   // + ((((%rip&0xf)>=0xb)<<3)+%rsp+8
2516   elfcpp::DW_CFA_nop,                   // Align to 32 bytes.
2517   elfcpp::DW_CFA_nop,
2518   elfcpp::DW_CFA_nop,
2519   elfcpp::DW_CFA_nop
2520 };
2521
2522 // The .eh_frame unwind information for the BND PLT.
2523 const unsigned char
2524 Output_data_plt_x86_64_bnd::plt_eh_frame_fde[plt_eh_frame_fde_size] =
2525 {
2526   0, 0, 0, 0,                           // Replaced with offset to .plt.
2527   0, 0, 0, 0,                           // Replaced with size of .plt.
2528   0,                                    // Augmentation size.
2529   elfcpp::DW_CFA_def_cfa_offset, 16,    // DW_CFA_def_cfa_offset: 16.
2530   elfcpp::DW_CFA_advance_loc + 6,       // Advance 6 to __PLT__ + 6.
2531   elfcpp::DW_CFA_def_cfa_offset, 24,    // DW_CFA_def_cfa_offset: 24.
2532   elfcpp::DW_CFA_advance_loc + 10,      // Advance 10 to __PLT__ + 16.
2533   elfcpp::DW_CFA_def_cfa_expression,    // DW_CFA_def_cfa_expression.
2534   11,                                   // Block length.
2535   elfcpp::DW_OP_breg7, 8,               // Push %rsp + 8.
2536   elfcpp::DW_OP_breg16, 0,              // Push %rip.
2537   elfcpp::DW_OP_lit15,                  // Push 0xf.
2538   elfcpp::DW_OP_and,                    // & (%rip & 0xf).
2539   elfcpp::DW_OP_lit5,                   // Push 5.
2540   elfcpp::DW_OP_ge,                     // >= ((%rip & 0xf) >= 5)
2541   elfcpp::DW_OP_lit3,                   // Push 3.
2542   elfcpp::DW_OP_shl,                    // << (((%rip & 0xf) >= 5) << 3)
2543   elfcpp::DW_OP_plus,                   // + ((((%rip&0xf)>=5)<<3)+%rsp+8
2544   elfcpp::DW_CFA_nop,                   // Align to 32 bytes.
2545   elfcpp::DW_CFA_nop,
2546   elfcpp::DW_CFA_nop,
2547   elfcpp::DW_CFA_nop
2548 };
2549
2550 // The .eh_frame unwind information for the BND PLT.
2551 template<int size>
2552 const unsigned char
2553 Output_data_plt_x86_64_ibt<size>::plt_eh_frame_fde[plt_eh_frame_fde_size] =
2554 {
2555   0, 0, 0, 0,                           // Replaced with offset to .plt.
2556   0, 0, 0, 0,                           // Replaced with size of .plt.
2557   0,                                    // Augmentation size.
2558   elfcpp::DW_CFA_def_cfa_offset, 16,    // DW_CFA_def_cfa_offset: 16.
2559   elfcpp::DW_CFA_advance_loc + 6,       // Advance 6 to __PLT__ + 6.
2560   elfcpp::DW_CFA_def_cfa_offset, 24,    // DW_CFA_def_cfa_offset: 24.
2561   elfcpp::DW_CFA_advance_loc + 10,      // Advance 10 to __PLT__ + 16.
2562   elfcpp::DW_CFA_def_cfa_expression,    // DW_CFA_def_cfa_expression.
2563   11,                                   // Block length.
2564   elfcpp::DW_OP_breg7, 8,               // Push %rsp + 8.
2565   elfcpp::DW_OP_breg16, 0,              // Push %rip.
2566   elfcpp::DW_OP_lit15,                  // Push 0xf.
2567   elfcpp::DW_OP_and,                    // & (%rip & 0xf).
2568   elfcpp::DW_OP_lit9,                   // Push 9.
2569   elfcpp::DW_OP_ge,                     // >= ((%rip & 0xf) >= 9)
2570   elfcpp::DW_OP_lit3,                   // Push 3.
2571   elfcpp::DW_OP_shl,                    // << (((%rip & 0xf) >= 9) << 3)
2572   elfcpp::DW_OP_plus,                   // + ((((%rip&0xf)>=9)<<3)+%rsp+8
2573   elfcpp::DW_CFA_nop,                   // Align to 32 bytes.
2574   elfcpp::DW_CFA_nop,
2575   elfcpp::DW_CFA_nop,
2576   elfcpp::DW_CFA_nop
2577 };
2578
2579 // Write out the PLT.  This uses the hand-coded instructions above,
2580 // and adjusts them as needed.  This is specified by the AMD64 ABI.
2581
2582 template<int size>
2583 void
2584 Output_data_plt_x86_64<size>::do_write(Output_file* of)
2585 {
2586   const off_t offset = this->offset();
2587   const section_size_type oview_size =
2588     convert_to_section_size_type(this->data_size());
2589   unsigned char* const oview = of->get_output_view(offset, oview_size);
2590
2591   const off_t got_file_offset = this->got_plt_->offset();
2592   gold_assert(parameters->incremental_update()
2593               || (got_file_offset + this->got_plt_->data_size()
2594                   == this->got_irelative_->offset()));
2595   const section_size_type got_size =
2596     convert_to_section_size_type(this->got_plt_->data_size()
2597                                  + this->got_irelative_->data_size());
2598   unsigned char* const got_view = of->get_output_view(got_file_offset,
2599                                                       got_size);
2600
2601   unsigned char* pov = oview;
2602
2603   // The base address of the .plt section.
2604   typename elfcpp::Elf_types<size>::Elf_Addr plt_address = this->address();
2605   // The base address of the .got section.
2606   typename elfcpp::Elf_types<size>::Elf_Addr got_base = this->got_->address();
2607   // The base address of the PLT portion of the .got section,
2608   // which is where the GOT pointer will point, and where the
2609   // three reserved GOT entries are located.
2610   typename elfcpp::Elf_types<size>::Elf_Addr got_address
2611     = this->got_plt_->address();
2612
2613   this->fill_first_plt_entry(pov, got_address, plt_address);
2614   pov += this->get_plt_entry_size();
2615
2616   // The first three entries in the GOT are reserved, and are written
2617   // by Output_data_got_plt_x86_64::do_write.
2618   unsigned char* got_pov = got_view + 24;
2619
2620   unsigned int plt_offset = this->get_plt_entry_size();
2621   unsigned int got_offset = 24;
2622   const unsigned int count = this->count_ + this->irelative_count_;
2623   for (unsigned int plt_index = 0;
2624        plt_index < count;
2625        ++plt_index,
2626          pov += this->get_plt_entry_size(),
2627          got_pov += 8,
2628          plt_offset += this->get_plt_entry_size(),
2629          got_offset += 8)
2630     {
2631       // Set and adjust the PLT entry itself.
2632       unsigned int lazy_offset = this->fill_plt_entry(pov,
2633                                                       got_address, plt_address,
2634                                                       got_offset, plt_offset,
2635                                                       plt_index);
2636
2637       // Set the entry in the GOT.
2638       elfcpp::Swap<64, false>::writeval(got_pov,
2639                                         plt_address + plt_offset + lazy_offset);
2640     }
2641
2642   if (this->has_tlsdesc_entry())
2643     {
2644       // Set and adjust the reserved TLSDESC PLT entry.
2645       unsigned int tlsdesc_got_offset = this->get_tlsdesc_got_offset();
2646       this->fill_tlsdesc_entry(pov, got_address, plt_address, got_base,
2647                                tlsdesc_got_offset, plt_offset);
2648       pov += this->get_plt_entry_size();
2649     }
2650
2651   gold_assert(static_cast<section_size_type>(pov - oview) == oview_size);
2652   gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size);
2653
2654   of->write_output_view(offset, oview_size, oview);
2655   of->write_output_view(got_file_offset, got_size, got_view);
2656 }
2657
2658 // Write out the BND PLT.
2659
2660 void
2661 Output_data_plt_x86_64_bnd::do_write(Output_file* of)
2662 {
2663   const off_t offset = this->offset();
2664   const section_size_type oview_size =
2665     convert_to_section_size_type(this->data_size());
2666   unsigned char* const oview = of->get_output_view(offset, oview_size);
2667
2668   Output_data_got<64, false>* got = this->got();
2669   Output_data_got_plt_x86_64* got_plt = this->got_plt();
2670   Output_data_space* got_irelative = this->got_irelative();
2671
2672   const off_t got_file_offset = got_plt->offset();
2673   gold_assert(parameters->incremental_update()
2674               || (got_file_offset + got_plt->data_size()
2675                   == got_irelative->offset()));
2676   const section_size_type got_size =
2677     convert_to_section_size_type(got_plt->data_size()
2678                                  + got_irelative->data_size());
2679   unsigned char* const got_view = of->get_output_view(got_file_offset,
2680                                                       got_size);
2681
2682   unsigned char* pov = oview;
2683
2684   // The base address of the .plt section.
2685   elfcpp::Elf_types<64>::Elf_Addr plt_address = this->address();
2686   // The base address of the .got section.
2687   elfcpp::Elf_types<64>::Elf_Addr got_base = got->address();
2688   // The base address of the PLT portion of the .got section,
2689   // which is where the GOT pointer will point, and where the
2690   // three reserved GOT entries are located.
2691   elfcpp::Elf_types<64>::Elf_Addr got_address = got_plt->address();
2692
2693   this->fill_first_plt_entry(pov, got_address, plt_address);
2694   pov += plt_entry_size;
2695
2696   // The first three entries in the GOT are reserved, and are written
2697   // by Output_data_got_plt_x86_64::do_write.
2698   unsigned char* got_pov = got_view + 24;
2699
2700   unsigned int plt_offset = plt_entry_size;
2701   unsigned int got_offset = 24;
2702   const unsigned int count = this->entry_count();
2703   for (unsigned int plt_index = 0;
2704        plt_index < count;
2705        ++plt_index,
2706          pov += plt_entry_size,
2707          got_pov += 8,
2708          plt_offset += plt_entry_size,
2709          got_offset += 8)
2710     {
2711       // Set and adjust the PLT entry itself.
2712       unsigned int lazy_offset = this->fill_plt_entry(pov,
2713                                                       got_address, plt_address,
2714                                                       got_offset, plt_offset,
2715                                                       plt_index);
2716
2717       // Set the entry in the GOT.
2718       elfcpp::Swap<64, false>::writeval(got_pov,
2719                                         plt_address + plt_offset + lazy_offset);
2720     }
2721
2722   if (this->has_tlsdesc_entry())
2723     {
2724       // Set and adjust the reserved TLSDESC PLT entry.
2725       unsigned int tlsdesc_got_offset = this->get_tlsdesc_got_offset();
2726       this->fill_tlsdesc_entry(pov, got_address, plt_address, got_base,
2727                                tlsdesc_got_offset, plt_offset);
2728       pov += this->get_plt_entry_size();
2729     }
2730
2731   // Write the additional PLT.
2732   got_offset = 24;
2733   for (unsigned int plt_index = 0;
2734        plt_index < count;
2735        ++plt_index,
2736          pov += aplt_entry_size,
2737          plt_offset += aplt_entry_size,
2738          got_offset += 8)
2739     {
2740       // Set and adjust the APLT entry.
2741       this->fill_aplt_entry(pov, got_address, plt_address, got_offset,
2742                             plt_offset, plt_index);
2743     }
2744
2745   gold_assert(static_cast<section_size_type>(pov - oview) == oview_size);
2746   gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size);
2747
2748   of->write_output_view(offset, oview_size, oview);
2749   of->write_output_view(got_file_offset, got_size, got_view);
2750 }
2751
2752 // Write out the IBT PLT.
2753
2754 template<int size>
2755 void
2756 Output_data_plt_x86_64_ibt<size>::do_write(Output_file* of)
2757 {
2758   const off_t offset = this->offset();
2759   const section_size_type oview_size =
2760     convert_to_section_size_type(this->data_size());
2761   unsigned char* const oview = of->get_output_view(offset, oview_size);
2762
2763   Output_data_got<64, false>* got = this->got();
2764   Output_data_got_plt_x86_64* got_plt = this->got_plt();
2765   Output_data_space* got_irelative = this->got_irelative();
2766
2767   const off_t got_file_offset = got_plt->offset();
2768   gold_assert(parameters->incremental_update()
2769               || (got_file_offset + got_plt->data_size()
2770                   == got_irelative->offset()));
2771   const section_size_type got_size =
2772     convert_to_section_size_type(got_plt->data_size()
2773                                  + got_irelative->data_size());
2774   unsigned char* const got_view = of->get_output_view(got_file_offset,
2775                                                       got_size);
2776
2777   unsigned char* pov = oview;
2778
2779   // The base address of the .plt section.
2780   elfcpp::Elf_types<64>::Elf_Addr plt_address = this->address();
2781   // The base address of the .got section.
2782   elfcpp::Elf_types<64>::Elf_Addr got_base = got->address();
2783   // The base address of the PLT portion of the .got section,
2784   // which is where the GOT pointer will point, and where the
2785   // three reserved GOT entries are located.
2786   elfcpp::Elf_types<64>::Elf_Addr got_address = got_plt->address();
2787
2788   this->fill_first_plt_entry(pov, got_address, plt_address);
2789   pov += plt_entry_size;
2790
2791   // The first three entries in the GOT are reserved, and are written
2792   // by Output_data_got_plt_x86_64::do_write.
2793   unsigned char* got_pov = got_view + 24;
2794
2795   unsigned int plt_offset = plt_entry_size;
2796   unsigned int got_offset = 24;
2797   const unsigned int count = this->entry_count();
2798   for (unsigned int plt_index = 0;
2799        plt_index < count;
2800        ++plt_index,
2801          pov += plt_entry_size,
2802          got_pov += 8,
2803          plt_offset += plt_entry_size,
2804          got_offset += 8)
2805     {
2806       // Set and adjust the PLT entry itself.
2807       unsigned int lazy_offset = this->fill_plt_entry(pov,
2808                                                       got_address, plt_address,
2809                                                       got_offset, plt_offset,
2810                                                       plt_index);
2811
2812       // Set the entry in the GOT.
2813       elfcpp::Swap<64, false>::writeval(got_pov,
2814                                         plt_address + plt_offset + lazy_offset);
2815     }
2816
2817   if (this->has_tlsdesc_entry())
2818     {
2819       // Set and adjust the reserved TLSDESC PLT entry.
2820       unsigned int tlsdesc_got_offset = this->get_tlsdesc_got_offset();
2821       this->fill_tlsdesc_entry(pov, got_address, plt_address, got_base,
2822                                tlsdesc_got_offset, plt_offset);
2823       pov += this->get_plt_entry_size();
2824     }
2825
2826   // Write the additional PLT.
2827   got_offset = 24;
2828   for (unsigned int plt_index = 0;
2829        plt_index < count;
2830        ++plt_index,
2831          pov += aplt_entry_size,
2832          plt_offset += aplt_entry_size,
2833          got_offset += 8)
2834     {
2835       // Set and adjust the APLT entry.
2836       this->fill_aplt_entry(pov, got_address, plt_address, got_offset,
2837                             plt_offset, plt_index);
2838     }
2839
2840   gold_assert(static_cast<section_size_type>(pov - oview) == oview_size);
2841   gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size);
2842
2843   of->write_output_view(offset, oview_size, oview);
2844   of->write_output_view(got_file_offset, got_size, got_view);
2845 }
2846
2847 // Create the PLT section.
2848
2849 template<int size>
2850 void
2851 Target_x86_64<size>::make_plt_section(Symbol_table* symtab, Layout* layout)
2852 {
2853   if (this->plt_ == NULL)
2854     {
2855       // Create the GOT sections first.
2856       this->got_section(symtab, layout);
2857
2858       this->plt_ = this->make_data_plt(layout, this->got_, this->got_plt_,
2859                                        this->got_irelative_);
2860
2861       // Add unwind information if requested.
2862       if (parameters->options().ld_generated_unwind_info())
2863         this->plt_->add_eh_frame(layout);
2864
2865       layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
2866                                       (elfcpp::SHF_ALLOC
2867                                        | elfcpp::SHF_EXECINSTR),
2868                                       this->plt_, ORDER_PLT, false);
2869
2870       // Make the sh_info field of .rela.plt point to .plt.
2871       Output_section* rela_plt_os = this->plt_->rela_plt()->output_section();
2872       rela_plt_os->set_info_section(this->plt_->output_section());
2873     }
2874 }
2875
2876 template<>
2877 Output_data_plt_x86_64<32>*
2878 Target_x86_64<32>::do_make_data_plt(Layout* layout,
2879                                     Output_data_got<64, false>* got,
2880                                     Output_data_got_plt_x86_64* got_plt,
2881                                     Output_data_space* got_irelative)
2882 {
2883   if (this->feature_1_ & elfcpp::GNU_PROPERTY_X86_FEATURE_1_IBT)
2884     return new Output_data_plt_x86_64_ibt<32>(layout, got, got_plt,
2885                                               got_irelative);
2886   return new Output_data_plt_x86_64_standard<32>(layout, got, got_plt,
2887                                                  got_irelative);
2888 }
2889
2890 template<>
2891 Output_data_plt_x86_64<64>*
2892 Target_x86_64<64>::do_make_data_plt(Layout* layout,
2893                                     Output_data_got<64, false>* got,
2894                                     Output_data_got_plt_x86_64* got_plt,
2895                                     Output_data_space* got_irelative)
2896 {
2897   if (this->feature_1_ & elfcpp::GNU_PROPERTY_X86_FEATURE_1_IBT)
2898     return new Output_data_plt_x86_64_ibt<64>(layout, got, got_plt,
2899                                               got_irelative);
2900   else if (parameters->options().bndplt())
2901     return new Output_data_plt_x86_64_bnd(layout, got, got_plt,
2902                                           got_irelative);
2903   else
2904     return new Output_data_plt_x86_64_standard<64>(layout, got, got_plt,
2905                                                    got_irelative);
2906 }
2907
2908 template<>
2909 Output_data_plt_x86_64<32>*
2910 Target_x86_64<32>::do_make_data_plt(Layout* layout,
2911                                     Output_data_got<64, false>* got,
2912                                     Output_data_got_plt_x86_64* got_plt,
2913                                     Output_data_space* got_irelative,
2914                                     unsigned int plt_count)
2915 {
2916   if (this->feature_1_ & elfcpp::GNU_PROPERTY_X86_FEATURE_1_IBT)
2917     return new Output_data_plt_x86_64_ibt<32>(layout, got, got_plt,
2918                                               got_irelative, plt_count);
2919   return new Output_data_plt_x86_64_standard<32>(layout, got, got_plt,
2920                                                  got_irelative, plt_count);
2921 }
2922
2923 template<>
2924 Output_data_plt_x86_64<64>*
2925 Target_x86_64<64>::do_make_data_plt(Layout* layout,
2926                                     Output_data_got<64, false>* got,
2927                                     Output_data_got_plt_x86_64* got_plt,
2928                                     Output_data_space* got_irelative,
2929                                     unsigned int plt_count)
2930 {
2931   if (this->feature_1_ & elfcpp::GNU_PROPERTY_X86_FEATURE_1_IBT)
2932     return new Output_data_plt_x86_64_ibt<64>(layout, got, got_plt,
2933                                               got_irelative, plt_count);
2934   else if (parameters->options().bndplt())
2935     return new Output_data_plt_x86_64_bnd(layout, got, got_plt,
2936                                           got_irelative, plt_count);
2937   else
2938     return new Output_data_plt_x86_64_standard<64>(layout, got, got_plt,
2939                                                    got_irelative,
2940                                                    plt_count);
2941 }
2942
2943 // Return the section for TLSDESC relocations.
2944
2945 template<int size>
2946 typename Target_x86_64<size>::Reloc_section*
2947 Target_x86_64<size>::rela_tlsdesc_section(Layout* layout) const
2948 {
2949   return this->plt_section()->rela_tlsdesc(layout);
2950 }
2951
2952 // Create a PLT entry for a global symbol.
2953
2954 template<int size>
2955 void
2956 Target_x86_64<size>::make_plt_entry(Symbol_table* symtab, Layout* layout,
2957                                     Symbol* gsym)
2958 {
2959   if (gsym->has_plt_offset())
2960     return;
2961
2962   if (this->plt_ == NULL)
2963     this->make_plt_section(symtab, layout);
2964
2965   this->plt_->add_entry(symtab, layout, gsym);
2966 }
2967
2968 // Make a PLT entry for a local STT_GNU_IFUNC symbol.
2969
2970 template<int size>
2971 void
2972 Target_x86_64<size>::make_local_ifunc_plt_entry(
2973     Symbol_table* symtab, Layout* layout,
2974     Sized_relobj_file<size, false>* relobj,
2975     unsigned int local_sym_index)
2976 {
2977   if (relobj->local_has_plt_offset(local_sym_index))
2978     return;
2979   if (this->plt_ == NULL)
2980     this->make_plt_section(symtab, layout);
2981   unsigned int plt_offset = this->plt_->add_local_ifunc_entry(symtab, layout,
2982                                                               relobj,
2983                                                               local_sym_index);
2984   relobj->set_local_plt_offset(local_sym_index, plt_offset);
2985 }
2986
2987 // Return the number of entries in the PLT.
2988
2989 template<int size>
2990 unsigned int
2991 Target_x86_64<size>::plt_entry_count() const
2992 {
2993   if (this->plt_ == NULL)
2994     return 0;
2995   return this->plt_->entry_count();
2996 }
2997
2998 // Return the offset of the first non-reserved PLT entry.
2999
3000 template<int size>
3001 unsigned int
3002 Target_x86_64<size>::first_plt_entry_offset() const
3003 {
3004   if (this->plt_ == NULL)
3005     return 0;
3006   return this->plt_->first_plt_entry_offset();
3007 }
3008
3009 // Return the size of each PLT entry.
3010
3011 template<int size>
3012 unsigned int
3013 Target_x86_64<size>::plt_entry_size() const
3014 {
3015   if (this->plt_ == NULL)
3016     return 0;
3017   return this->plt_->get_plt_entry_size();
3018 }
3019
3020 // Create the GOT and PLT sections for an incremental update.
3021
3022 template<int size>
3023 Output_data_got_base*
3024 Target_x86_64<size>::init_got_plt_for_update(Symbol_table* symtab,
3025                                        Layout* layout,
3026                                        unsigned int got_count,
3027                                        unsigned int plt_count)
3028 {
3029   gold_assert(this->got_ == NULL);
3030
3031   this->got_ = new Output_data_got<64, false>(got_count * 8);
3032   layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
3033                                   (elfcpp::SHF_ALLOC
3034                                    | elfcpp::SHF_WRITE),
3035                                   this->got_, ORDER_RELRO_LAST,
3036                                   true);
3037
3038   // Add the three reserved entries.
3039   this->got_plt_ = new Output_data_got_plt_x86_64(layout, (plt_count + 3) * 8);
3040   layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
3041                                   (elfcpp::SHF_ALLOC
3042                                    | elfcpp::SHF_WRITE),
3043                                   this->got_plt_, ORDER_NON_RELRO_FIRST,
3044                                   false);
3045
3046   // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
3047   this->global_offset_table_ =
3048     symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
3049                                   Symbol_table::PREDEFINED,
3050                                   this->got_plt_,
3051                                   0, 0, elfcpp::STT_OBJECT,
3052                                   elfcpp::STB_LOCAL,
3053                                   elfcpp::STV_HIDDEN, 0,
3054                                   false, false);
3055
3056   // If there are any TLSDESC relocations, they get GOT entries in
3057   // .got.plt after the jump slot entries.
3058   // FIXME: Get the count for TLSDESC entries.
3059   this->got_tlsdesc_ = new Output_data_got<64, false>(0);
3060   layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
3061                                   elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE,
3062                                   this->got_tlsdesc_,
3063                                   ORDER_NON_RELRO_FIRST, false);
3064
3065   // If there are any IRELATIVE relocations, they get GOT entries in
3066   // .got.plt after the jump slot and TLSDESC entries.
3067   this->got_irelative_ = new Output_data_space(0, 8, "** GOT IRELATIVE PLT");
3068   layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
3069                                   elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE,
3070                                   this->got_irelative_,
3071                                   ORDER_NON_RELRO_FIRST, false);
3072
3073   // Create the PLT section.
3074   this->plt_ = this->make_data_plt(layout, this->got_,
3075                                    this->got_plt_,
3076                                    this->got_irelative_,
3077                                    plt_count);
3078
3079   // Add unwind information if requested.
3080   if (parameters->options().ld_generated_unwind_info())
3081     this->plt_->add_eh_frame(layout);
3082
3083   layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
3084                                   elfcpp::SHF_ALLOC | elfcpp::SHF_EXECINSTR,
3085                                   this->plt_, ORDER_PLT, false);
3086
3087   // Make the sh_info field of .rela.plt point to .plt.
3088   Output_section* rela_plt_os = this->plt_->rela_plt()->output_section();
3089   rela_plt_os->set_info_section(this->plt_->output_section());
3090
3091   // Create the rela_dyn section.
3092   this->rela_dyn_section(layout);
3093
3094   return this->got_;
3095 }
3096
3097 // Reserve a GOT entry for a local symbol, and regenerate any
3098 // necessary dynamic relocations.
3099
3100 template<int size>
3101 void
3102 Target_x86_64<size>::reserve_local_got_entry(
3103     unsigned int got_index,
3104     Sized_relobj<size, false>* obj,
3105     unsigned int r_sym,
3106     unsigned int got_type)
3107 {
3108   unsigned int got_offset = got_index * 8;
3109   Reloc_section* rela_dyn = this->rela_dyn_section(NULL);
3110
3111   this->got_->reserve_local(got_index, obj, r_sym, got_type);
3112   switch (got_type)
3113     {
3114     case GOT_TYPE_STANDARD:
3115       if (parameters->options().output_is_position_independent())
3116         rela_dyn->add_local_relative(obj, r_sym, elfcpp::R_X86_64_RELATIVE,
3117                                      this->got_, got_offset, 0, false);
3118       break;
3119     case GOT_TYPE_TLS_OFFSET:
3120       rela_dyn->add_local(obj, r_sym, elfcpp::R_X86_64_TPOFF64,
3121                           this->got_, got_offset, 0);
3122       break;
3123     case GOT_TYPE_TLS_PAIR:
3124       this->got_->reserve_slot(got_index + 1);
3125       rela_dyn->add_local(obj, r_sym, elfcpp::R_X86_64_DTPMOD64,
3126                           this->got_, got_offset, 0);
3127       break;
3128     case GOT_TYPE_TLS_DESC:
3129       gold_fatal(_("TLS_DESC not yet supported for incremental linking"));
3130       // this->got_->reserve_slot(got_index + 1);
3131       // rela_dyn->add_target_specific(elfcpp::R_X86_64_TLSDESC, arg,
3132       //                               this->got_, got_offset, 0);
3133       break;
3134     default:
3135       gold_unreachable();
3136     }
3137 }
3138
3139 // Reserve a GOT entry for a global symbol, and regenerate any
3140 // necessary dynamic relocations.
3141
3142 template<int size>
3143 void
3144 Target_x86_64<size>::reserve_global_got_entry(unsigned int got_index,
3145                                               Symbol* gsym,
3146                                               unsigned int got_type)
3147 {
3148   unsigned int got_offset = got_index * 8;
3149   Reloc_section* rela_dyn = this->rela_dyn_section(NULL);
3150
3151   this->got_->reserve_global(got_index, gsym, got_type);
3152   switch (got_type)
3153     {
3154     case GOT_TYPE_STANDARD:
3155       if (!gsym->final_value_is_known())
3156         {
3157           if (gsym->is_from_dynobj()
3158               || gsym->is_undefined()
3159               || gsym->is_preemptible()
3160               || gsym->type() == elfcpp::STT_GNU_IFUNC)
3161             rela_dyn->add_global(gsym, elfcpp::R_X86_64_GLOB_DAT,
3162                                  this->got_, got_offset, 0);
3163           else
3164             rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_RELATIVE,
3165                                           this->got_, got_offset, 0, false);
3166         }
3167       break;
3168     case GOT_TYPE_TLS_OFFSET:
3169       rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_TPOFF64,
3170                                     this->got_, got_offset, 0, false);
3171       break;
3172     case GOT_TYPE_TLS_PAIR:
3173       this->got_->reserve_slot(got_index + 1);
3174       rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_DTPMOD64,
3175                                     this->got_, got_offset, 0, false);
3176       rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_DTPOFF64,
3177                                     this->got_, got_offset + 8, 0, false);
3178       break;
3179     case GOT_TYPE_TLS_DESC:
3180       this->got_->reserve_slot(got_index + 1);
3181       rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_TLSDESC,
3182                                     this->got_, got_offset, 0, false);
3183       break;
3184     default:
3185       gold_unreachable();
3186     }
3187 }
3188
3189 // Register an existing PLT entry for a global symbol.
3190
3191 template<int size>
3192 void
3193 Target_x86_64<size>::register_global_plt_entry(Symbol_table* symtab,
3194                                                Layout* layout,
3195                                                unsigned int plt_index,
3196                                                Symbol* gsym)
3197 {
3198   gold_assert(this->plt_ != NULL);
3199   gold_assert(!gsym->has_plt_offset());
3200
3201   this->plt_->reserve_slot(plt_index);
3202
3203   gsym->set_plt_offset((plt_index + 1) * this->plt_entry_size());
3204
3205   unsigned int got_offset = (plt_index + 3) * 8;
3206   this->plt_->add_relocation(symtab, layout, gsym, got_offset);
3207 }
3208
3209 // Force a COPY relocation for a given symbol.
3210
3211 template<int size>
3212 void
3213 Target_x86_64<size>::emit_copy_reloc(
3214     Symbol_table* symtab, Symbol* sym, Output_section* os, off_t offset)
3215 {
3216   this->copy_relocs_.emit_copy_reloc(symtab,
3217                                      symtab->get_sized_symbol<size>(sym),
3218                                      os,
3219                                      offset,
3220                                      this->rela_dyn_section(NULL));
3221 }
3222
3223 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
3224
3225 template<int size>
3226 void
3227 Target_x86_64<size>::define_tls_base_symbol(Symbol_table* symtab,
3228                                             Layout* layout)
3229 {
3230   if (this->tls_base_symbol_defined_)
3231     return;
3232
3233   Output_segment* tls_segment = layout->tls_segment();
3234   if (tls_segment != NULL)
3235     {
3236       bool is_exec = parameters->options().output_is_executable();
3237       symtab->define_in_output_segment("_TLS_MODULE_BASE_", NULL,
3238                                        Symbol_table::PREDEFINED,
3239                                        tls_segment, 0, 0,
3240                                        elfcpp::STT_TLS,
3241                                        elfcpp::STB_LOCAL,
3242                                        elfcpp::STV_HIDDEN, 0,
3243                                        (is_exec
3244                                         ? Symbol::SEGMENT_END
3245                                         : Symbol::SEGMENT_START),
3246                                        true);
3247     }
3248   this->tls_base_symbol_defined_ = true;
3249 }
3250
3251 // Create the reserved PLT and GOT entries for the TLS descriptor resolver.
3252
3253 template<int size>
3254 void
3255 Target_x86_64<size>::reserve_tlsdesc_entries(Symbol_table* symtab,
3256                                              Layout* layout)
3257 {
3258   if (this->plt_ == NULL)
3259     this->make_plt_section(symtab, layout);
3260
3261   if (!this->plt_->has_tlsdesc_entry())
3262     {
3263       // Allocate the TLSDESC_GOT entry.
3264       Output_data_got<64, false>* got = this->got_section(symtab, layout);
3265       unsigned int got_offset = got->add_constant(0);
3266
3267       // Allocate the TLSDESC_PLT entry.
3268       this->plt_->reserve_tlsdesc_entry(got_offset);
3269     }
3270 }
3271
3272 // Create a GOT entry for the TLS module index.
3273
3274 template<int size>
3275 unsigned int
3276 Target_x86_64<size>::got_mod_index_entry(Symbol_table* symtab, Layout* layout,
3277                                          Sized_relobj_file<size, false>* object)
3278 {
3279   if (this->got_mod_index_offset_ == -1U)
3280     {
3281       gold_assert(symtab != NULL && layout != NULL && object != NULL);
3282       Reloc_section* rela_dyn = this->rela_dyn_section(layout);
3283       Output_data_got<64, false>* got = this->got_section(symtab, layout);
3284       unsigned int got_offset = got->add_constant(0);
3285       rela_dyn->add_local(object, 0, elfcpp::R_X86_64_DTPMOD64, got,
3286                           got_offset, 0);
3287       got->add_constant(0);
3288       this->got_mod_index_offset_ = got_offset;
3289     }
3290   return this->got_mod_index_offset_;
3291 }
3292
3293 // Optimize the TLS relocation type based on what we know about the
3294 // symbol.  IS_FINAL is true if the final address of this symbol is
3295 // known at link time.
3296
3297 template<int size>
3298 tls::Tls_optimization
3299 Target_x86_64<size>::optimize_tls_reloc(bool is_final, int r_type)
3300 {
3301   // If we are generating a shared library, then we can't do anything
3302   // in the linker.
3303   if (parameters->options().shared())
3304     return tls::TLSOPT_NONE;
3305
3306   switch (r_type)
3307     {
3308     case elfcpp::R_X86_64_TLSGD:
3309     case elfcpp::R_X86_64_GOTPC32_TLSDESC:
3310     case elfcpp::R_X86_64_TLSDESC_CALL:
3311       // These are General-Dynamic which permits fully general TLS
3312       // access.  Since we know that we are generating an executable,
3313       // we can convert this to Initial-Exec.  If we also know that
3314       // this is a local symbol, we can further switch to Local-Exec.
3315       if (is_final)
3316         return tls::TLSOPT_TO_LE;
3317       return tls::TLSOPT_TO_IE;
3318
3319     case elfcpp::R_X86_64_TLSLD:
3320       // This is Local-Dynamic, which refers to a local symbol in the
3321       // dynamic TLS block.  Since we know that we generating an
3322       // executable, we can switch to Local-Exec.
3323       return tls::TLSOPT_TO_LE;
3324
3325     case elfcpp::R_X86_64_DTPOFF32:
3326     case elfcpp::R_X86_64_DTPOFF64:
3327       // Another Local-Dynamic reloc.
3328       return tls::TLSOPT_TO_LE;
3329
3330     case elfcpp::R_X86_64_GOTTPOFF:
3331       // These are Initial-Exec relocs which get the thread offset
3332       // from the GOT.  If we know that we are linking against the
3333       // local symbol, we can switch to Local-Exec, which links the
3334       // thread offset into the instruction.
3335       if (is_final)
3336         return tls::TLSOPT_TO_LE;
3337       return tls::TLSOPT_NONE;
3338
3339     case elfcpp::R_X86_64_TPOFF32:
3340       // When we already have Local-Exec, there is nothing further we
3341       // can do.
3342       return tls::TLSOPT_NONE;
3343
3344     default:
3345       gold_unreachable();
3346     }
3347 }
3348
3349 // Get the Reference_flags for a particular relocation.
3350
3351 template<int size>
3352 int
3353 Target_x86_64<size>::Scan::get_reference_flags(unsigned int r_type)
3354 {
3355   switch (r_type)
3356     {
3357     case elfcpp::R_X86_64_NONE:
3358     case elfcpp::R_X86_64_GNU_VTINHERIT:
3359     case elfcpp::R_X86_64_GNU_VTENTRY:
3360     case elfcpp::R_X86_64_GOTPC32:
3361     case elfcpp::R_X86_64_GOTPC64:
3362       // No symbol reference.
3363       return 0;
3364
3365     case elfcpp::R_X86_64_64:
3366     case elfcpp::R_X86_64_32:
3367     case elfcpp::R_X86_64_32S:
3368     case elfcpp::R_X86_64_16:
3369     case elfcpp::R_X86_64_8:
3370       return Symbol::ABSOLUTE_REF;
3371
3372     case elfcpp::R_X86_64_PC64:
3373     case elfcpp::R_X86_64_PC32:
3374     case elfcpp::R_X86_64_PC32_BND:
3375     case elfcpp::R_X86_64_PC16:
3376     case elfcpp::R_X86_64_PC8:
3377     case elfcpp::R_X86_64_GOTOFF64:
3378       return Symbol::RELATIVE_REF;
3379
3380     case elfcpp::R_X86_64_PLT32:
3381     case elfcpp::R_X86_64_PLT32_BND:
3382     case elfcpp::R_X86_64_PLTOFF64:
3383       return Symbol::FUNCTION_CALL | Symbol::RELATIVE_REF;
3384
3385     case elfcpp::R_X86_64_GOT64:
3386     case elfcpp::R_X86_64_GOT32:
3387     case elfcpp::R_X86_64_GOTPCREL64:
3388     case elfcpp::R_X86_64_GOTPCREL:
3389     case elfcpp::R_X86_64_GOTPCRELX:
3390     case elfcpp::R_X86_64_REX_GOTPCRELX:
3391     case elfcpp::R_X86_64_GOTPLT64:
3392       // Absolute in GOT.
3393       return Symbol::ABSOLUTE_REF;
3394
3395     case elfcpp::R_X86_64_TLSGD:            // Global-dynamic
3396     case elfcpp::R_X86_64_GOTPC32_TLSDESC:  // Global-dynamic (from ~oliva url)
3397     case elfcpp::R_X86_64_TLSDESC_CALL:
3398     case elfcpp::R_X86_64_TLSLD:            // Local-dynamic
3399     case elfcpp::R_X86_64_DTPOFF32:
3400     case elfcpp::R_X86_64_DTPOFF64:
3401     case elfcpp::R_X86_64_GOTTPOFF:         // Initial-exec
3402     case elfcpp::R_X86_64_TPOFF32:          // Local-exec
3403       return Symbol::TLS_REF;
3404
3405     case elfcpp::R_X86_64_COPY:
3406     case elfcpp::R_X86_64_GLOB_DAT:
3407     case elfcpp::R_X86_64_JUMP_SLOT:
3408     case elfcpp::R_X86_64_RELATIVE:
3409     case elfcpp::R_X86_64_IRELATIVE:
3410     case elfcpp::R_X86_64_TPOFF64:
3411     case elfcpp::R_X86_64_DTPMOD64:
3412     case elfcpp::R_X86_64_TLSDESC:
3413     case elfcpp::R_X86_64_SIZE32:
3414     case elfcpp::R_X86_64_SIZE64:
3415     default:
3416       // Not expected.  We will give an error later.
3417       return 0;
3418     }
3419 }
3420
3421 // Report an unsupported relocation against a local symbol.
3422
3423 template<int size>
3424 void
3425 Target_x86_64<size>::Scan::unsupported_reloc_local(
3426      Sized_relobj_file<size, false>* object,
3427      unsigned int r_type)
3428 {
3429   gold_error(_("%s: unsupported reloc %u against local symbol"),
3430              object->name().c_str(), r_type);
3431 }
3432
3433 // We are about to emit a dynamic relocation of type R_TYPE.  If the
3434 // dynamic linker does not support it, issue an error.  The GNU linker
3435 // only issues a non-PIC error for an allocated read-only section.
3436 // Here we know the section is allocated, but we don't know that it is
3437 // read-only.  But we check for all the relocation types which the
3438 // glibc dynamic linker supports, so it seems appropriate to issue an
3439 // error even if the section is not read-only.  If GSYM is not NULL,
3440 // it is the symbol the relocation is against; if it is NULL, the
3441 // relocation is against a local symbol.
3442
3443 template<int size>
3444 void
3445 Target_x86_64<size>::Scan::check_non_pic(Relobj* object, unsigned int r_type,
3446                                          Symbol* gsym)
3447 {
3448   switch (r_type)
3449     {
3450       // These are the relocation types supported by glibc for x86_64
3451       // which should always work.
3452     case elfcpp::R_X86_64_RELATIVE:
3453     case elfcpp::R_X86_64_IRELATIVE:
3454     case elfcpp::R_X86_64_GLOB_DAT:
3455     case elfcpp::R_X86_64_JUMP_SLOT:
3456     case elfcpp::R_X86_64_DTPMOD64:
3457     case elfcpp::R_X86_64_DTPOFF64:
3458     case elfcpp::R_X86_64_TPOFF64:
3459     case elfcpp::R_X86_64_64:
3460     case elfcpp::R_X86_64_COPY:
3461       return;
3462
3463       // glibc supports these reloc types, but they can overflow.
3464     case elfcpp::R_X86_64_PC32:
3465     case elfcpp::R_X86_64_PC32_BND:
3466       // A PC relative reference is OK against a local symbol or if
3467       // the symbol is defined locally.
3468       if (gsym == NULL
3469           || (!gsym->is_from_dynobj()
3470               && !gsym->is_undefined()
3471               && !gsym->is_preemptible()))
3472         return;
3473       // Fall through.
3474     case elfcpp::R_X86_64_32:
3475       // R_X86_64_32 is OK for x32.
3476       if (size == 32 && r_type == elfcpp::R_X86_64_32)
3477         return;
3478       if (this->issued_non_pic_error_)
3479         return;
3480       gold_assert(parameters->options().output_is_position_independent());
3481       if (gsym == NULL)
3482         object->error(_("requires dynamic R_X86_64_32 reloc which may "
3483                         "overflow at runtime; recompile with -fPIC"));
3484       else
3485         {
3486           const char *r_name;
3487           switch (r_type)
3488             {
3489             case elfcpp::R_X86_64_32:
3490               r_name = "R_X86_64_32";
3491               break;
3492             case elfcpp::R_X86_64_PC32:
3493               r_name = "R_X86_64_PC32";
3494               break;
3495             case elfcpp::R_X86_64_PC32_BND:
3496               r_name = "R_X86_64_PC32_BND";
3497               break;
3498             default:
3499               gold_unreachable();
3500               break;
3501             }
3502           object->error(_("requires dynamic %s reloc against '%s' "
3503                           "which may overflow at runtime; recompile "
3504                           "with -fPIC"),
3505                         r_name, gsym->name());
3506         }
3507       this->issued_non_pic_error_ = true;
3508       return;
3509
3510     default:
3511       // This prevents us from issuing more than one error per reloc
3512       // section.  But we can still wind up issuing more than one
3513       // error per object file.
3514       if (this->issued_non_pic_error_)
3515         return;
3516       gold_assert(parameters->options().output_is_position_independent());
3517       object->error(_("requires unsupported dynamic reloc %u; "
3518                       "recompile with -fPIC"),
3519                     r_type);
3520       this->issued_non_pic_error_ = true;
3521       return;
3522
3523     case elfcpp::R_X86_64_NONE:
3524       gold_unreachable();
3525     }
3526 }
3527
3528 // Return whether we need to make a PLT entry for a relocation of the
3529 // given type against a STT_GNU_IFUNC symbol.
3530
3531 template<int size>
3532 bool
3533 Target_x86_64<size>::Scan::reloc_needs_plt_for_ifunc(
3534      Sized_relobj_file<size, false>* object,
3535      unsigned int r_type)
3536 {
3537   int flags = Scan::get_reference_flags(r_type);
3538   if (flags & Symbol::TLS_REF)
3539     gold_error(_("%s: unsupported TLS reloc %u for IFUNC symbol"),
3540                object->name().c_str(), r_type);
3541   return flags != 0;
3542 }
3543
3544 // Scan a relocation for a local symbol.
3545
3546 template<int size>
3547 inline void
3548 Target_x86_64<size>::Scan::local(Symbol_table* symtab,
3549                                  Layout* layout,
3550                                  Target_x86_64<size>* target,
3551                                  Sized_relobj_file<size, false>* object,
3552                                  unsigned int data_shndx,
3553                                  Output_section* output_section,
3554                                  const elfcpp::Rela<size, false>& reloc,
3555                                  unsigned int r_type,
3556                                  const elfcpp::Sym<size, false>& lsym,
3557                                  bool is_discarded)
3558 {
3559   if (is_discarded)
3560     return;
3561
3562   // A local STT_GNU_IFUNC symbol may require a PLT entry.
3563   bool is_ifunc = lsym.get_st_type() == elfcpp::STT_GNU_IFUNC;
3564   if (is_ifunc && this->reloc_needs_plt_for_ifunc(object, r_type))
3565     {
3566       unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
3567       target->make_local_ifunc_plt_entry(symtab, layout, object, r_sym);
3568     }
3569
3570   switch (r_type)
3571     {
3572     case elfcpp::R_X86_64_NONE:
3573     case elfcpp::R_X86_64_GNU_VTINHERIT:
3574     case elfcpp::R_X86_64_GNU_VTENTRY:
3575       break;
3576
3577     case elfcpp::R_X86_64_64:
3578       // If building a shared library (or a position-independent
3579       // executable), we need to create a dynamic relocation for this
3580       // location.  The relocation applied at link time will apply the
3581       // link-time value, so we flag the location with an
3582       // R_X86_64_RELATIVE relocation so the dynamic loader can
3583       // relocate it easily.
3584       if (parameters->options().output_is_position_independent())
3585         {
3586           unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
3587           Reloc_section* rela_dyn = target->rela_dyn_section(layout);
3588           rela_dyn->add_local_relative(object, r_sym,
3589                                        (size == 32
3590                                         ? elfcpp::R_X86_64_RELATIVE64
3591                                         : elfcpp::R_X86_64_RELATIVE),
3592                                        output_section, data_shndx,
3593                                        reloc.get_r_offset(),
3594                                        reloc.get_r_addend(), is_ifunc);
3595         }
3596       break;
3597
3598     case elfcpp::R_X86_64_32:
3599     case elfcpp::R_X86_64_32S:
3600     case elfcpp::R_X86_64_16:
3601     case elfcpp::R_X86_64_8:
3602       // If building a shared library (or a position-independent
3603       // executable), we need to create a dynamic relocation for this
3604       // location.  We can't use an R_X86_64_RELATIVE relocation
3605       // because that is always a 64-bit relocation.
3606       if (parameters->options().output_is_position_independent())
3607         {
3608           // Use R_X86_64_RELATIVE relocation for R_X86_64_32 under x32.
3609           if (size == 32 && r_type == elfcpp::R_X86_64_32)
3610             {
3611               unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
3612               Reloc_section* rela_dyn = target->rela_dyn_section(layout);
3613               rela_dyn->add_local_relative(object, r_sym,
3614                                            elfcpp::R_X86_64_RELATIVE,
3615                                            output_section, data_shndx,
3616                                            reloc.get_r_offset(),
3617                                            reloc.get_r_addend(), is_ifunc);
3618               break;
3619             }
3620
3621           this->check_non_pic(object, r_type, NULL);
3622
3623           Reloc_section* rela_dyn = target->rela_dyn_section(layout);
3624           unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
3625           if (lsym.get_st_type() != elfcpp::STT_SECTION)
3626             rela_dyn->add_local(object, r_sym, r_type, output_section,
3627                                 data_shndx, reloc.get_r_offset(),
3628                                 reloc.get_r_addend());
3629           else
3630             {
3631               gold_assert(lsym.get_st_value() == 0);
3632               unsigned int shndx = lsym.get_st_shndx();
3633               bool is_ordinary;
3634               shndx = object->adjust_sym_shndx(r_sym, shndx,
3635                                                &is_ordinary);
3636               if (!is_ordinary)
3637                 object->error(_("section symbol %u has bad shndx %u"),
3638                               r_sym, shndx);
3639               else
3640                 rela_dyn->add_local_section(object, shndx,
3641                                             r_type, output_section,
3642                                             data_shndx, reloc.get_r_offset(),
3643                                             reloc.get_r_addend());
3644             }
3645         }
3646       break;
3647
3648     case elfcpp::R_X86_64_PC64:
3649     case elfcpp::R_X86_64_PC32:
3650     case elfcpp::R_X86_64_PC32_BND:
3651     case elfcpp::R_X86_64_PC16:
3652     case elfcpp::R_X86_64_PC8:
3653       break;
3654
3655     case elfcpp::R_X86_64_PLT32:
3656     case elfcpp::R_X86_64_PLT32_BND:
3657       // Since we know this is a local symbol, we can handle this as a
3658       // PC32 reloc.
3659       break;
3660
3661     case elfcpp::R_X86_64_GOTPC32:
3662     case elfcpp::R_X86_64_GOTOFF64:
3663     case elfcpp::R_X86_64_GOTPC64:
3664     case elfcpp::R_X86_64_PLTOFF64:
3665       // We need a GOT section.
3666       target->got_section(symtab, layout);
3667       // For PLTOFF64, we'd normally want a PLT section, but since we
3668       // know this is a local symbol, no PLT is needed.
3669       break;
3670
3671     case elfcpp::R_X86_64_GOT64:
3672     case elfcpp::R_X86_64_GOT32:
3673     case elfcpp::R_X86_64_GOTPCREL64:
3674     case elfcpp::R_X86_64_GOTPCREL:
3675     case elfcpp::R_X86_64_GOTPCRELX:
3676     case elfcpp::R_X86_64_REX_GOTPCRELX:
3677     case elfcpp::R_X86_64_GOTPLT64:
3678       {
3679         // The symbol requires a GOT section.
3680         Output_data_got<64, false>* got = target->got_section(symtab, layout);
3681
3682         // If the relocation symbol isn't IFUNC,
3683         // and is local, then we will convert
3684         // mov foo@GOTPCREL(%rip), %reg
3685         // to lea foo(%rip), %reg.
3686         // in Relocate::relocate.
3687         if (!parameters->incremental()
3688             && (r_type == elfcpp::R_X86_64_GOTPCREL
3689                 || r_type == elfcpp::R_X86_64_GOTPCRELX
3690                 || r_type == elfcpp::R_X86_64_REX_GOTPCRELX)
3691             && reloc.get_r_offset() >= 2
3692             && !is_ifunc)
3693           {
3694             section_size_type stype;
3695             const unsigned char* view = object->section_contents(data_shndx,
3696                                                                  &stype, true);
3697             if (view[reloc.get_r_offset() - 2] == 0x8b)
3698               break;
3699           }
3700
3701         // The symbol requires a GOT entry.
3702         unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
3703
3704         // For a STT_GNU_IFUNC symbol we want the PLT offset.  That
3705         // lets function pointers compare correctly with shared
3706         // libraries.  Otherwise we would need an IRELATIVE reloc.
3707         bool is_new;
3708         if (is_ifunc)
3709           is_new = got->add_local_plt(object, r_sym, GOT_TYPE_STANDARD);
3710         else
3711           is_new = got->add_local(object, r_sym, GOT_TYPE_STANDARD);
3712         if (is_new)
3713           {
3714             // If we are generating a shared object, we need to add a
3715             // dynamic relocation for this symbol's GOT entry.
3716             if (parameters->options().output_is_position_independent())
3717               {
3718                 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
3719                 // R_X86_64_RELATIVE assumes a 64-bit relocation.
3720                 if (r_type != elfcpp::R_X86_64_GOT32)
3721                   {
3722                     unsigned int got_offset =
3723                       object->local_got_offset(r_sym, GOT_TYPE_STANDARD);
3724                     rela_dyn->add_local_relative(object, r_sym,
3725                                                  elfcpp::R_X86_64_RELATIVE,
3726                                                  got, got_offset, 0, is_ifunc);
3727                   }
3728                 else
3729                   {
3730                     this->check_non_pic(object, r_type, NULL);
3731
3732                     gold_assert(lsym.get_st_type() != elfcpp::STT_SECTION);
3733                     rela_dyn->add_local(
3734                         object, r_sym, r_type, got,
3735                         object->local_got_offset(r_sym, GOT_TYPE_STANDARD), 0);
3736                   }
3737               }
3738           }
3739         // For GOTPLT64, we'd normally want a PLT section, but since
3740         // we know this is a local symbol, no PLT is needed.
3741       }
3742       break;
3743
3744     case elfcpp::R_X86_64_COPY:
3745     case elfcpp::R_X86_64_GLOB_DAT:
3746     case elfcpp::R_X86_64_JUMP_SLOT:
3747     case elfcpp::R_X86_64_RELATIVE:
3748     case elfcpp::R_X86_64_IRELATIVE:
3749       // These are outstanding tls relocs, which are unexpected when linking
3750     case elfcpp::R_X86_64_TPOFF64:
3751     case elfcpp::R_X86_64_DTPMOD64:
3752     case elfcpp::R_X86_64_TLSDESC:
3753       gold_error(_("%s: unexpected reloc %u in object file"),
3754                  object->name().c_str(), r_type);
3755       break;
3756
3757       // These are initial tls relocs, which are expected when linking
3758     case elfcpp::R_X86_64_TLSGD:            // Global-dynamic
3759     case elfcpp::R_X86_64_GOTPC32_TLSDESC:  // Global-dynamic (from ~oliva url)
3760     case elfcpp::R_X86_64_TLSDESC_CALL:
3761     case elfcpp::R_X86_64_TLSLD:            // Local-dynamic
3762     case elfcpp::R_X86_64_DTPOFF32:
3763     case elfcpp::R_X86_64_DTPOFF64:
3764     case elfcpp::R_X86_64_GOTTPOFF:         // Initial-exec
3765     case elfcpp::R_X86_64_TPOFF32:          // Local-exec
3766       {
3767         bool output_is_shared = parameters->options().shared();
3768         const tls::Tls_optimization optimized_type
3769             = Target_x86_64<size>::optimize_tls_reloc(!output_is_shared,
3770                                                       r_type);
3771         switch (r_type)
3772           {
3773           case elfcpp::R_X86_64_TLSGD:       // General-dynamic
3774             if (optimized_type == tls::TLSOPT_NONE)
3775               {
3776                 // Create a pair of GOT entries for the module index and
3777                 // dtv-relative offset.
3778                 Output_data_got<64, false>* got
3779                     = target->got_section(symtab, layout);
3780                 unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
3781                 unsigned int shndx = lsym.get_st_shndx();
3782                 bool is_ordinary;
3783                 shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
3784                 if (!is_ordinary)
3785                   object->error(_("local symbol %u has bad shndx %u"),
3786                               r_sym, shndx);
3787                 else
3788                   got->add_local_pair_with_rel(object, r_sym,
3789                                                shndx,
3790                                                GOT_TYPE_TLS_PAIR,
3791                                                target->rela_dyn_section(layout),
3792                                                elfcpp::R_X86_64_DTPMOD64);
3793               }
3794             else if (optimized_type != tls::TLSOPT_TO_LE)
3795               unsupported_reloc_local(object, r_type);
3796             break;
3797
3798           case elfcpp::R_X86_64_GOTPC32_TLSDESC:
3799             target->define_tls_base_symbol(symtab, layout);
3800             if (optimized_type == tls::TLSOPT_NONE)
3801               {
3802                 // Create reserved PLT and GOT entries for the resolver.
3803                 target->reserve_tlsdesc_entries(symtab, layout);
3804
3805                 // Generate a double GOT entry with an
3806                 // R_X86_64_TLSDESC reloc.  The R_X86_64_TLSDESC reloc
3807                 // is resolved lazily, so the GOT entry needs to be in
3808                 // an area in .got.plt, not .got.  Call got_section to
3809                 // make sure the section has been created.
3810                 target->got_section(symtab, layout);
3811                 Output_data_got<64, false>* got = target->got_tlsdesc_section();
3812                 unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
3813                 if (!object->local_has_got_offset(r_sym, GOT_TYPE_TLS_DESC))
3814                   {
3815                     unsigned int got_offset = got->add_constant(0);
3816                     got->add_constant(0);
3817                     object->set_local_got_offset(r_sym, GOT_TYPE_TLS_DESC,
3818                                                  got_offset);
3819                     Reloc_section* rt = target->rela_tlsdesc_section(layout);
3820                     // We store the arguments we need in a vector, and
3821                     // use the index into the vector as the parameter
3822                     // to pass to the target specific routines.
3823                     uintptr_t intarg = target->add_tlsdesc_info(object, r_sym);
3824                     void* arg = reinterpret_cast<void*>(intarg);
3825                     rt->add_target_specific(elfcpp::R_X86_64_TLSDESC, arg,
3826                                             got, got_offset, 0);
3827                   }
3828               }
3829             else if (optimized_type != tls::TLSOPT_TO_LE)
3830               unsupported_reloc_local(object, r_type);
3831             break;
3832
3833           case elfcpp::R_X86_64_TLSDESC_CALL:
3834             break;
3835
3836           case elfcpp::R_X86_64_TLSLD:       // Local-dynamic
3837             if (optimized_type == tls::TLSOPT_NONE)
3838               {
3839                 // Create a GOT entry for the module index.
3840                 target->got_mod_index_entry(symtab, layout, object);
3841               }
3842             else if (optimized_type != tls::TLSOPT_TO_LE)
3843               unsupported_reloc_local(object, r_type);
3844             break;
3845
3846           case elfcpp::R_X86_64_DTPOFF32:
3847           case elfcpp::R_X86_64_DTPOFF64:
3848             break;
3849
3850           case elfcpp::R_X86_64_GOTTPOFF:    // Initial-exec
3851             layout->set_has_static_tls();
3852             if (optimized_type == tls::TLSOPT_NONE)
3853               {
3854                 // Create a GOT entry for the tp-relative offset.
3855                 Output_data_got<64, false>* got
3856                     = target->got_section(symtab, layout);
3857                 unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
3858                 got->add_local_with_rel(object, r_sym, GOT_TYPE_TLS_OFFSET,
3859                                         target->rela_dyn_section(layout),
3860                                         elfcpp::R_X86_64_TPOFF64);
3861               }
3862             else if (optimized_type != tls::TLSOPT_TO_LE)
3863               unsupported_reloc_local(object, r_type);
3864             break;
3865
3866           case elfcpp::R_X86_64_TPOFF32:     // Local-exec
3867             layout->set_has_static_tls();
3868             if (output_is_shared)
3869               unsupported_reloc_local(object, r_type);
3870             break;
3871
3872           default:
3873             gold_unreachable();
3874           }
3875       }
3876       break;
3877
3878     case elfcpp::R_X86_64_SIZE32:
3879     case elfcpp::R_X86_64_SIZE64:
3880     default:
3881       gold_error(_("%s: unsupported reloc %u against local symbol"),
3882                  object->name().c_str(), r_type);
3883       break;
3884     }
3885 }
3886
3887
3888 // Report an unsupported relocation against a global symbol.
3889
3890 template<int size>
3891 void
3892 Target_x86_64<size>::Scan::unsupported_reloc_global(
3893     Sized_relobj_file<size, false>* object,
3894     unsigned int r_type,
3895     Symbol* gsym)
3896 {
3897   gold_error(_("%s: unsupported reloc %u against global symbol %s"),
3898              object->name().c_str(), r_type, gsym->demangled_name().c_str());
3899 }
3900
3901 // Returns true if this relocation type could be that of a function pointer.
3902 template<int size>
3903 inline bool
3904 Target_x86_64<size>::Scan::possible_function_pointer_reloc(
3905     Sized_relobj_file<size, false>* src_obj,
3906     unsigned int src_indx,
3907     unsigned int r_offset,
3908     unsigned int r_type)
3909 {
3910   switch (r_type)
3911     {
3912     case elfcpp::R_X86_64_64:
3913     case elfcpp::R_X86_64_32:
3914     case elfcpp::R_X86_64_32S:
3915     case elfcpp::R_X86_64_16:
3916     case elfcpp::R_X86_64_8:
3917     case elfcpp::R_X86_64_GOT64:
3918     case elfcpp::R_X86_64_GOT32:
3919     case elfcpp::R_X86_64_GOTPCREL64:
3920     case elfcpp::R_X86_64_GOTPCREL:
3921     case elfcpp::R_X86_64_GOTPCRELX:
3922     case elfcpp::R_X86_64_REX_GOTPCRELX:
3923     case elfcpp::R_X86_64_GOTPLT64:
3924       {
3925         return true;
3926       }
3927     case elfcpp::R_X86_64_PC32:
3928       {
3929         // This relocation may be used both for function calls and
3930         // for taking address of a function. We distinguish between
3931         // them by checking the opcodes.
3932         uint64_t sh_flags = src_obj->section_flags(src_indx);
3933         bool is_executable = (sh_flags & elfcpp::SHF_EXECINSTR) != 0;
3934         if (is_executable)
3935           {
3936             section_size_type stype;
3937             const unsigned char* view = src_obj->section_contents(src_indx,
3938                                                                   &stype,
3939                                                                   true);
3940
3941             // call
3942             if (r_offset >= 1
3943                 && view[r_offset - 1] == 0xe8)
3944               return false;
3945
3946             // jmp
3947             if (r_offset >= 1
3948                 && view[r_offset - 1] == 0xe9)
3949               return false;
3950
3951             // jo/jno/jb/jnb/je/jne/jna/ja/js/jns/jp/jnp/jl/jge/jle/jg
3952             if (r_offset >= 2
3953                 && view[r_offset - 2] == 0x0f
3954                 && view[r_offset - 1] >= 0x80
3955                 && view[r_offset - 1] <= 0x8f)
3956               return false;
3957           }
3958
3959         // Be conservative and treat all others as function pointers.
3960         return true;
3961       }
3962     }
3963   return false;
3964 }
3965
3966 // For safe ICF, scan a relocation for a local symbol to check if it
3967 // corresponds to a function pointer being taken.  In that case mark
3968 // the function whose pointer was taken as not foldable.
3969
3970 template<int size>
3971 inline bool
3972 Target_x86_64<size>::Scan::local_reloc_may_be_function_pointer(
3973   Symbol_table* ,
3974   Layout* ,
3975   Target_x86_64<size>* ,
3976   Sized_relobj_file<size, false>* src_obj,
3977   unsigned int src_indx,
3978   Output_section* ,
3979   const elfcpp::Rela<size, false>& reloc,
3980   unsigned int r_type,
3981   const elfcpp::Sym<size, false>&)
3982 {
3983   // When building a shared library, do not fold any local symbols as it is
3984   // not possible to distinguish pointer taken versus a call by looking at
3985   // the relocation types.
3986   if (parameters->options().shared())
3987     return true;
3988
3989   return possible_function_pointer_reloc(src_obj, src_indx,
3990                                          reloc.get_r_offset(), r_type);
3991 }
3992
3993 // For safe ICF, scan a relocation for a global symbol to check if it
3994 // corresponds to a function pointer being taken.  In that case mark
3995 // the function whose pointer was taken as not foldable.
3996
3997 template<int size>
3998 inline bool
3999 Target_x86_64<size>::Scan::global_reloc_may_be_function_pointer(
4000   Symbol_table*,
4001   Layout* ,
4002   Target_x86_64<size>* ,
4003   Sized_relobj_file<size, false>* src_obj,
4004   unsigned int src_indx,
4005   Output_section* ,
4006   const elfcpp::Rela<size, false>& reloc,
4007   unsigned int r_type,
4008   Symbol* gsym)
4009 {
4010   // When building a shared library, do not fold symbols whose visibility
4011   // is hidden, internal or protected.
4012   if (parameters->options().shared()
4013       && (gsym->visibility() == elfcpp::STV_INTERNAL
4014           || gsym->visibility() == elfcpp::STV_PROTECTED
4015           || gsym->visibility() == elfcpp::STV_HIDDEN))
4016     return true;
4017
4018   return possible_function_pointer_reloc(src_obj, src_indx,
4019                                          reloc.get_r_offset(), r_type);
4020 }
4021
4022 // Scan a relocation for a global symbol.
4023
4024 template<int size>
4025 inline void
4026 Target_x86_64<size>::Scan::global(Symbol_table* symtab,
4027                             Layout* layout,
4028                             Target_x86_64<size>* target,
4029                             Sized_relobj_file<size, false>* object,
4030                             unsigned int data_shndx,
4031                             Output_section* output_section,
4032                             const elfcpp::Rela<size, false>& reloc,
4033                             unsigned int r_type,
4034                             Symbol* gsym)
4035 {
4036   // A STT_GNU_IFUNC symbol may require a PLT entry.
4037   if (gsym->type() == elfcpp::STT_GNU_IFUNC
4038       && this->reloc_needs_plt_for_ifunc(object, r_type))
4039     target->make_plt_entry(symtab, layout, gsym);
4040
4041   switch (r_type)
4042     {
4043     case elfcpp::R_X86_64_NONE:
4044     case elfcpp::R_X86_64_GNU_VTINHERIT:
4045     case elfcpp::R_X86_64_GNU_VTENTRY:
4046       break;
4047
4048     case elfcpp::R_X86_64_64:
4049     case elfcpp::R_X86_64_32:
4050     case elfcpp::R_X86_64_32S:
4051     case elfcpp::R_X86_64_16:
4052     case elfcpp::R_X86_64_8:
4053       {
4054         // Make a PLT entry if necessary.
4055         if (gsym->needs_plt_entry())
4056           {
4057             target->make_plt_entry(symtab, layout, gsym);
4058             // Since this is not a PC-relative relocation, we may be
4059             // taking the address of a function. In that case we need to
4060             // set the entry in the dynamic symbol table to the address of
4061             // the PLT entry.
4062             if (gsym->is_from_dynobj() && !parameters->options().shared())
4063               gsym->set_needs_dynsym_value();
4064           }
4065         // Make a dynamic relocation if necessary.
4066         if (gsym->needs_dynamic_reloc(Scan::get_reference_flags(r_type)))
4067           {
4068             if (!parameters->options().output_is_position_independent()
4069                 && gsym->may_need_copy_reloc())
4070               {
4071                 target->copy_reloc(symtab, layout, object,
4072                                    data_shndx, output_section, gsym, reloc);
4073               }
4074             else if (((size == 64 && r_type == elfcpp::R_X86_64_64)
4075                       || (size == 32 && r_type == elfcpp::R_X86_64_32))
4076                      && gsym->type() == elfcpp::STT_GNU_IFUNC
4077                      && gsym->can_use_relative_reloc(false)
4078                      && !gsym->is_from_dynobj()
4079                      && !gsym->is_undefined()
4080                      && !gsym->is_preemptible())
4081               {
4082                 // Use an IRELATIVE reloc for a locally defined
4083                 // STT_GNU_IFUNC symbol.  This makes a function
4084                 // address in a PIE executable match the address in a
4085                 // shared library that it links against.
4086                 Reloc_section* rela_dyn =
4087                   target->rela_irelative_section(layout);
4088                 unsigned int r_type = elfcpp::R_X86_64_IRELATIVE;
4089                 rela_dyn->add_symbolless_global_addend(gsym, r_type,
4090                                                        output_section, object,
4091                                                        data_shndx,
4092                                                        reloc.get_r_offset(),
4093                                                        reloc.get_r_addend());
4094               }
4095             else if (((size == 64 && r_type == elfcpp::R_X86_64_64)
4096                       || (size == 32 && r_type == elfcpp::R_X86_64_32))
4097                      && gsym->can_use_relative_reloc(false))
4098               {
4099                 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
4100                 rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_RELATIVE,
4101                                               output_section, object,
4102                                               data_shndx,
4103                                               reloc.get_r_offset(),
4104                                               reloc.get_r_addend(), false);
4105               }
4106             else
4107               {
4108                 this->check_non_pic(object, r_type, gsym);
4109                 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
4110                 rela_dyn->add_global(gsym, r_type, output_section, object,
4111                                      data_shndx, reloc.get_r_offset(),
4112                                      reloc.get_r_addend());
4113               }
4114           }
4115       }
4116       break;
4117
4118     case elfcpp::R_X86_64_PC64:
4119     case elfcpp::R_X86_64_PC32:
4120     case elfcpp::R_X86_64_PC32_BND:
4121     case elfcpp::R_X86_64_PC16:
4122     case elfcpp::R_X86_64_PC8:
4123       {
4124         // Make a PLT entry if necessary.
4125         if (gsym->needs_plt_entry())
4126           target->make_plt_entry(symtab, layout, gsym);
4127         // Make a dynamic relocation if necessary.
4128         if (gsym->needs_dynamic_reloc(Scan::get_reference_flags(r_type)))
4129           {
4130             if (parameters->options().output_is_executable()
4131                 && gsym->may_need_copy_reloc())
4132               {
4133                 target->copy_reloc(symtab, layout, object,
4134                                    data_shndx, output_section, gsym, reloc);
4135               }
4136             else
4137               {
4138                 this->check_non_pic(object, r_type, gsym);
4139                 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
4140                 rela_dyn->add_global(gsym, r_type, output_section, object,
4141                                      data_shndx, reloc.get_r_offset(),
4142                                      reloc.get_r_addend());
4143               }
4144           }
4145       }
4146       break;
4147
4148     case elfcpp::R_X86_64_GOT64:
4149     case elfcpp::R_X86_64_GOT32:
4150     case elfcpp::R_X86_64_GOTPCREL64:
4151     case elfcpp::R_X86_64_GOTPCREL:
4152     case elfcpp::R_X86_64_GOTPCRELX:
4153     case elfcpp::R_X86_64_REX_GOTPCRELX:
4154     case elfcpp::R_X86_64_GOTPLT64:
4155       {
4156         // The symbol requires a GOT entry.
4157         Output_data_got<64, false>* got = target->got_section(symtab, layout);
4158
4159         // If we convert this from
4160         // mov foo@GOTPCREL(%rip), %reg
4161         // to lea foo(%rip), %reg.
4162         // OR
4163         // if we convert
4164         // (callq|jmpq) *foo@GOTPCRELX(%rip) to
4165         // (callq|jmpq) foo
4166         // in Relocate::relocate, then there is nothing to do here.
4167         // We cannot make these optimizations in incremental linking mode,
4168         // because we look at the opcode to decide whether or not to make
4169         // change, and during an incremental update, the change may have
4170         // already been applied.
4171
4172         Lazy_view<size> view(object, data_shndx);
4173         size_t r_offset = reloc.get_r_offset();
4174         if (!parameters->incremental()
4175             && r_offset >= 2
4176             && Target_x86_64<size>::can_convert_mov_to_lea(gsym, r_type,
4177                                                            r_offset, &view))
4178           break;
4179
4180         if (!parameters->incremental()
4181             && r_offset >= 2
4182             && Target_x86_64<size>::can_convert_callq_to_direct(gsym, r_type,
4183                                                                 r_offset,
4184                                                                 &view))
4185           break;
4186
4187         if (gsym->final_value_is_known())
4188           {
4189             // For a STT_GNU_IFUNC symbol we want the PLT address.
4190             if (gsym->type() == elfcpp::STT_GNU_IFUNC)
4191               got->add_global_plt(gsym, GOT_TYPE_STANDARD);
4192             else
4193               got->add_global(gsym, GOT_TYPE_STANDARD);
4194           }
4195         else
4196           {
4197             // If this symbol is not fully resolved, we need to add a
4198             // dynamic relocation for it.
4199             Reloc_section* rela_dyn = target->rela_dyn_section(layout);
4200
4201             // Use a GLOB_DAT rather than a RELATIVE reloc if:
4202             //
4203             // 1) The symbol may be defined in some other module.
4204             //
4205             // 2) We are building a shared library and this is a
4206             // protected symbol; using GLOB_DAT means that the dynamic
4207             // linker can use the address of the PLT in the main
4208             // executable when appropriate so that function address
4209             // comparisons work.
4210             //
4211             // 3) This is a STT_GNU_IFUNC symbol in position dependent
4212             // code, again so that function address comparisons work.
4213             if (gsym->is_from_dynobj()
4214                 || gsym->is_undefined()
4215                 || gsym->is_preemptible()
4216                 || (gsym->visibility() == elfcpp::STV_PROTECTED
4217                     && parameters->options().shared())
4218                 || (gsym->type() == elfcpp::STT_GNU_IFUNC
4219                     && parameters->options().output_is_position_independent()))
4220               got->add_global_with_rel(gsym, GOT_TYPE_STANDARD, rela_dyn,
4221                                        elfcpp::R_X86_64_GLOB_DAT);
4222             else
4223               {
4224                 // For a STT_GNU_IFUNC symbol we want to write the PLT
4225                 // offset into the GOT, so that function pointer
4226                 // comparisons work correctly.
4227                 bool is_new;
4228                 if (gsym->type() != elfcpp::STT_GNU_IFUNC)
4229                   is_new = got->add_global(gsym, GOT_TYPE_STANDARD);
4230                 else
4231                   {
4232                     is_new = got->add_global_plt(gsym, GOT_TYPE_STANDARD);
4233                     // Tell the dynamic linker to use the PLT address
4234                     // when resolving relocations.
4235                     if (gsym->is_from_dynobj()
4236                         && !parameters->options().shared())
4237                       gsym->set_needs_dynsym_value();
4238                   }
4239                 if (is_new)
4240                   {
4241                     unsigned int got_off = gsym->got_offset(GOT_TYPE_STANDARD);
4242                     rela_dyn->add_global_relative(gsym,
4243                                                   elfcpp::R_X86_64_RELATIVE,
4244                                                   got, got_off, 0, false);
4245                   }
4246               }
4247           }
4248       }
4249       break;
4250
4251     case elfcpp::R_X86_64_PLT32:
4252     case elfcpp::R_X86_64_PLT32_BND:
4253       // If the symbol is fully resolved, this is just a PC32 reloc.
4254       // Otherwise we need a PLT entry.
4255       if (gsym->final_value_is_known())
4256         break;
4257       // If building a shared library, we can also skip the PLT entry
4258       // if the symbol is defined in the output file and is protected
4259       // or hidden.
4260       if (gsym->is_defined()
4261           && !gsym->is_from_dynobj()
4262           && !gsym->is_preemptible())
4263         break;
4264       target->make_plt_entry(symtab, layout, gsym);
4265       break;
4266
4267     case elfcpp::R_X86_64_GOTPC32:
4268     case elfcpp::R_X86_64_GOTOFF64:
4269     case elfcpp::R_X86_64_GOTPC64:
4270     case elfcpp::R_X86_64_PLTOFF64:
4271       // We need a GOT section.
4272       target->got_section(symtab, layout);
4273       // For PLTOFF64, we also need a PLT entry (but only if the
4274       // symbol is not fully resolved).
4275       if (r_type == elfcpp::R_X86_64_PLTOFF64
4276           && !gsym->final_value_is_known())
4277         target->make_plt_entry(symtab, layout, gsym);
4278       break;
4279
4280     case elfcpp::R_X86_64_COPY:
4281     case elfcpp::R_X86_64_GLOB_DAT:
4282     case elfcpp::R_X86_64_JUMP_SLOT:
4283     case elfcpp::R_X86_64_RELATIVE:
4284     case elfcpp::R_X86_64_IRELATIVE:
4285       // These are outstanding tls relocs, which are unexpected when linking
4286     case elfcpp::R_X86_64_TPOFF64:
4287     case elfcpp::R_X86_64_DTPMOD64:
4288     case elfcpp::R_X86_64_TLSDESC:
4289       gold_error(_("%s: unexpected reloc %u in object file"),
4290                  object->name().c_str(), r_type);
4291       break;
4292
4293       // These are initial tls relocs, which are expected for global()
4294     case elfcpp::R_X86_64_TLSGD:            // Global-dynamic
4295     case elfcpp::R_X86_64_GOTPC32_TLSDESC:  // Global-dynamic (from ~oliva url)
4296     case elfcpp::R_X86_64_TLSDESC_CALL:
4297     case elfcpp::R_X86_64_TLSLD:            // Local-dynamic
4298     case elfcpp::R_X86_64_DTPOFF32:
4299     case elfcpp::R_X86_64_DTPOFF64:
4300     case elfcpp::R_X86_64_GOTTPOFF:         // Initial-exec
4301     case elfcpp::R_X86_64_TPOFF32:          // Local-exec
4302       {
4303         // For the Initial-Exec model, we can treat undef symbols as final
4304         // when building an executable.
4305         const bool is_final = (gsym->final_value_is_known() ||
4306                                (r_type == elfcpp::R_X86_64_GOTTPOFF &&
4307                                 gsym->is_undefined() &&
4308                                 parameters->options().output_is_executable()));
4309         const tls::Tls_optimization optimized_type
4310             = Target_x86_64<size>::optimize_tls_reloc(is_final, r_type);
4311         switch (r_type)
4312           {
4313           case elfcpp::R_X86_64_TLSGD:       // General-dynamic
4314             if (optimized_type == tls::TLSOPT_NONE)
4315               {
4316                 // Create a pair of GOT entries for the module index and
4317                 // dtv-relative offset.
4318                 Output_data_got<64, false>* got
4319                     = target->got_section(symtab, layout);
4320                 got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_PAIR,
4321                                               target->rela_dyn_section(layout),
4322                                               elfcpp::R_X86_64_DTPMOD64,
4323                                               elfcpp::R_X86_64_DTPOFF64);
4324               }
4325             else if (optimized_type == tls::TLSOPT_TO_IE)
4326               {
4327                 // Create a GOT entry for the tp-relative offset.
4328                 Output_data_got<64, false>* got
4329                     = target->got_section(symtab, layout);
4330                 got->add_global_with_rel(gsym, GOT_TYPE_TLS_OFFSET,
4331                                          target->rela_dyn_section(layout),
4332                                          elfcpp::R_X86_64_TPOFF64);
4333               }
4334             else if (optimized_type != tls::TLSOPT_TO_LE)
4335               unsupported_reloc_global(object, r_type, gsym);
4336             break;
4337
4338           case elfcpp::R_X86_64_GOTPC32_TLSDESC:
4339             target->define_tls_base_symbol(symtab, layout);
4340             if (optimized_type == tls::TLSOPT_NONE)
4341               {
4342                 // Create reserved PLT and GOT entries for the resolver.
4343                 target->reserve_tlsdesc_entries(symtab, layout);
4344
4345                 // Create a double GOT entry with an R_X86_64_TLSDESC
4346                 // reloc.  The R_X86_64_TLSDESC reloc is resolved
4347                 // lazily, so the GOT entry needs to be in an area in
4348                 // .got.plt, not .got.  Call got_section to make sure
4349                 // the section has been created.
4350                 target->got_section(symtab, layout);
4351                 Output_data_got<64, false>* got = target->got_tlsdesc_section();
4352                 Reloc_section* rt = target->rela_tlsdesc_section(layout);
4353                 got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_DESC, rt,
4354                                               elfcpp::R_X86_64_TLSDESC, 0);
4355               }
4356             else if (optimized_type == tls::TLSOPT_TO_IE)
4357               {
4358                 // Create a GOT entry for the tp-relative offset.
4359                 Output_data_got<64, false>* got
4360                     = target->got_section(symtab, layout);
4361                 got->add_global_with_rel(gsym, GOT_TYPE_TLS_OFFSET,
4362                                          target->rela_dyn_section(layout),
4363                                          elfcpp::R_X86_64_TPOFF64);
4364               }
4365             else if (optimized_type != tls::TLSOPT_TO_LE)
4366               unsupported_reloc_global(object, r_type, gsym);
4367             break;
4368
4369           case elfcpp::R_X86_64_TLSDESC_CALL:
4370             break;
4371
4372           case elfcpp::R_X86_64_TLSLD:       // Local-dynamic
4373             if (optimized_type == tls::TLSOPT_NONE)
4374               {
4375                 // Create a GOT entry for the module index.
4376                 target->got_mod_index_entry(symtab, layout, object);
4377               }
4378             else if (optimized_type != tls::TLSOPT_TO_LE)
4379               unsupported_reloc_global(object, r_type, gsym);
4380             break;
4381
4382           case elfcpp::R_X86_64_DTPOFF32:
4383           case elfcpp::R_X86_64_DTPOFF64:
4384             break;
4385
4386           case elfcpp::R_X86_64_GOTTPOFF:    // Initial-exec
4387             layout->set_has_static_tls();
4388             if (optimized_type == tls::TLSOPT_NONE)
4389               {
4390                 // Create a GOT entry for the tp-relative offset.
4391                 Output_data_got<64, false>* got
4392                     = target->got_section(symtab, layout);
4393                 got->add_global_with_rel(gsym, GOT_TYPE_TLS_OFFSET,
4394                                          target->rela_dyn_section(layout),
4395                                          elfcpp::R_X86_64_TPOFF64);
4396               }
4397             else if (optimized_type != tls::TLSOPT_TO_LE)
4398               unsupported_reloc_global(object, r_type, gsym);
4399             break;
4400
4401           case elfcpp::R_X86_64_TPOFF32:     // Local-exec
4402             layout->set_has_static_tls();
4403             if (parameters->options().shared())
4404               unsupported_reloc_global(object, r_type, gsym);
4405             break;
4406
4407           default:
4408             gold_unreachable();
4409           }
4410       }
4411       break;
4412
4413     case elfcpp::R_X86_64_SIZE32:
4414     case elfcpp::R_X86_64_SIZE64:
4415     default:
4416       gold_error(_("%s: unsupported reloc %u against global symbol %s"),
4417                  object->name().c_str(), r_type,
4418                  gsym->demangled_name().c_str());
4419       break;
4420     }
4421 }
4422
4423 template<int size>
4424 void
4425 Target_x86_64<size>::gc_process_relocs(Symbol_table* symtab,
4426                                        Layout* layout,
4427                                        Sized_relobj_file<size, false>* object,
4428                                        unsigned int data_shndx,
4429                                        unsigned int sh_type,
4430                                        const unsigned char* prelocs,
4431                                        size_t reloc_count,
4432                                        Output_section* output_section,
4433                                        bool needs_special_offset_handling,
4434                                        size_t local_symbol_count,
4435                                        const unsigned char* plocal_symbols)
4436 {
4437   typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, false>
4438       Classify_reloc;
4439
4440   if (sh_type == elfcpp::SHT_REL)
4441     {
4442       return;
4443     }
4444
4445    gold::gc_process_relocs<size, false, Target_x86_64<size>, Scan,
4446                            Classify_reloc>(
4447     symtab,
4448     layout,
4449     this,
4450     object,
4451     data_shndx,
4452     prelocs,
4453     reloc_count,
4454     output_section,
4455     needs_special_offset_handling,
4456     local_symbol_count,
4457     plocal_symbols);
4458
4459 }
4460 // Scan relocations for a section.
4461
4462 template<int size>
4463 void
4464 Target_x86_64<size>::scan_relocs(Symbol_table* symtab,
4465                                  Layout* layout,
4466                                  Sized_relobj_file<size, false>* object,
4467                                  unsigned int data_shndx,
4468                                  unsigned int sh_type,
4469                                  const unsigned char* prelocs,
4470                                  size_t reloc_count,
4471                                  Output_section* output_section,
4472                                  bool needs_special_offset_handling,
4473                                  size_t local_symbol_count,
4474                                  const unsigned char* plocal_symbols)
4475 {
4476   typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, false>
4477       Classify_reloc;
4478
4479   if (sh_type == elfcpp::SHT_REL)
4480     {
4481       gold_error(_("%s: unsupported REL reloc section"),
4482                  object->name().c_str());
4483       return;
4484     }
4485
4486   gold::scan_relocs<size, false, Target_x86_64<size>, Scan, Classify_reloc>(
4487     symtab,
4488     layout,
4489     this,
4490     object,
4491     data_shndx,
4492     prelocs,
4493     reloc_count,
4494     output_section,
4495     needs_special_offset_handling,
4496     local_symbol_count,
4497     plocal_symbols);
4498 }
4499
4500 // Finalize the sections.
4501
4502 template<int size>
4503 void
4504 Target_x86_64<size>::do_finalize_sections(
4505     Layout* layout,
4506     const Input_objects*,
4507     Symbol_table* symtab)
4508 {
4509   const Reloc_section* rel_plt = (this->plt_ == NULL
4510                                   ? NULL
4511                                   : this->plt_->rela_plt());
4512   layout->add_target_dynamic_tags(false, this->got_plt_, rel_plt,
4513                                   this->rela_dyn_, true, false);
4514
4515   // Fill in some more dynamic tags.
4516   Output_data_dynamic* const odyn = layout->dynamic_data();
4517   if (odyn != NULL)
4518     {
4519       if (this->plt_ != NULL
4520           && this->plt_->output_section() != NULL
4521           && this->plt_->has_tlsdesc_entry())
4522         {
4523           unsigned int plt_offset = this->plt_->get_tlsdesc_plt_offset();
4524           unsigned int got_offset = this->plt_->get_tlsdesc_got_offset();
4525           this->got_->finalize_data_size();
4526           odyn->add_section_plus_offset(elfcpp::DT_TLSDESC_PLT,
4527                                         this->plt_, plt_offset);
4528           odyn->add_section_plus_offset(elfcpp::DT_TLSDESC_GOT,
4529                                         this->got_, got_offset);
4530         }
4531     }
4532
4533   // Emit any relocs we saved in an attempt to avoid generating COPY
4534   // relocs.
4535   if (this->copy_relocs_.any_saved_relocs())
4536     this->copy_relocs_.emit(this->rela_dyn_section(layout));
4537
4538   // Set the size of the _GLOBAL_OFFSET_TABLE_ symbol to the size of
4539   // the .got.plt section.
4540   Symbol* sym = this->global_offset_table_;
4541   if (sym != NULL)
4542     {
4543       uint64_t data_size = this->got_plt_->current_data_size();
4544       symtab->get_sized_symbol<size>(sym)->set_symsize(data_size);
4545     }
4546
4547   if (parameters->doing_static_link()
4548       && (this->plt_ == NULL || !this->plt_->has_irelative_section()))
4549     {
4550       // If linking statically, make sure that the __rela_iplt symbols
4551       // were defined if necessary, even if we didn't create a PLT.
4552       static const Define_symbol_in_segment syms[] =
4553         {
4554           {
4555             "__rela_iplt_start",        // name
4556             elfcpp::PT_LOAD,            // segment_type
4557             elfcpp::PF_W,               // segment_flags_set
4558             elfcpp::PF(0),              // segment_flags_clear
4559             0,                          // value
4560             0,                          // size
4561             elfcpp::STT_NOTYPE,         // type
4562             elfcpp::STB_GLOBAL,         // binding
4563             elfcpp::STV_HIDDEN,         // visibility
4564             0,                          // nonvis
4565             Symbol::SEGMENT_START,      // offset_from_base
4566             true                        // only_if_ref
4567           },
4568           {
4569             "__rela_iplt_end",          // name
4570             elfcpp::PT_LOAD,            // segment_type
4571             elfcpp::PF_W,               // segment_flags_set
4572             elfcpp::PF(0),              // segment_flags_clear
4573             0,                          // value
4574             0,                          // size
4575             elfcpp::STT_NOTYPE,         // type
4576             elfcpp::STB_GLOBAL,         // binding
4577             elfcpp::STV_HIDDEN,         // visibility
4578             0,                          // nonvis
4579             Symbol::SEGMENT_START,      // offset_from_base
4580             true                        // only_if_ref
4581           }
4582         };
4583
4584       symtab->define_symbols(layout, 2, syms,
4585                              layout->script_options()->saw_sections_clause());
4586     }
4587 }
4588
4589 // For x32, we need to handle PC-relative relocations using full 64-bit
4590 // arithmetic, so that we can detect relocation overflows properly.
4591 // This class overrides the pcrela32_check methods from the defaults in
4592 // Relocate_functions in reloc.h.
4593
4594 template<int size>
4595 class X86_64_relocate_functions : public Relocate_functions<size, false>
4596 {
4597  public:
4598   typedef Relocate_functions<size, false> Base;
4599
4600   // Do a simple PC relative relocation with the addend in the
4601   // relocation.
4602   static inline typename Base::Reloc_status
4603   pcrela32_check(unsigned char* view,
4604                  typename elfcpp::Elf_types<64>::Elf_Addr value,
4605                  typename elfcpp::Elf_types<64>::Elf_Swxword addend,
4606                  typename elfcpp::Elf_types<64>::Elf_Addr address)
4607   {
4608     typedef typename elfcpp::Swap<32, false>::Valtype Valtype;
4609     Valtype* wv = reinterpret_cast<Valtype*>(view);
4610     value = value + addend - address;
4611     elfcpp::Swap<32, false>::writeval(wv, value);
4612     return (Bits<32>::has_overflow(value)
4613             ? Base::RELOC_OVERFLOW : Base::RELOC_OK);
4614   }
4615
4616   // Do a simple PC relative relocation with a Symbol_value with the
4617   // addend in the relocation.
4618   static inline typename Base::Reloc_status
4619   pcrela32_check(unsigned char* view,
4620                  const Sized_relobj_file<size, false>* object,
4621                  const Symbol_value<size>* psymval,
4622                  typename elfcpp::Elf_types<64>::Elf_Swxword addend,
4623                  typename elfcpp::Elf_types<64>::Elf_Addr address)
4624   {
4625     typedef typename elfcpp::Swap<32, false>::Valtype Valtype;
4626     Valtype* wv = reinterpret_cast<Valtype*>(view);
4627     typename elfcpp::Elf_types<64>::Elf_Addr value;
4628     if (addend >= 0)
4629       value = psymval->value(object, addend);
4630     else
4631       {
4632         // For negative addends, get the symbol value without
4633         // the addend, then add the addend using 64-bit arithmetic.
4634         value = psymval->value(object, 0);
4635         value += addend;
4636       }
4637     value -= address;
4638     elfcpp::Swap<32, false>::writeval(wv, value);
4639     return (Bits<32>::has_overflow(value)
4640             ? Base::RELOC_OVERFLOW : Base::RELOC_OK);
4641   }
4642 };
4643
4644 // Perform a relocation.
4645
4646 template<int size>
4647 inline bool
4648 Target_x86_64<size>::Relocate::relocate(
4649     const Relocate_info<size, false>* relinfo,
4650     unsigned int,
4651     Target_x86_64<size>* target,
4652     Output_section*,
4653     size_t relnum,
4654     const unsigned char* preloc,
4655     const Sized_symbol<size>* gsym,
4656     const Symbol_value<size>* psymval,
4657     unsigned char* view,
4658     typename elfcpp::Elf_types<size>::Elf_Addr address,
4659     section_size_type view_size)
4660 {
4661   typedef X86_64_relocate_functions<size> Reloc_funcs;
4662   const elfcpp::Rela<size, false> rela(preloc);
4663   unsigned int r_type = elfcpp::elf_r_type<size>(rela.get_r_info());
4664
4665   if (this->skip_call_tls_get_addr_)
4666     {
4667       if ((r_type != elfcpp::R_X86_64_PLT32
4668            && r_type != elfcpp::R_X86_64_GOTPCREL
4669            && r_type != elfcpp::R_X86_64_GOTPCRELX
4670            && r_type != elfcpp::R_X86_64_PLT32_BND
4671            && r_type != elfcpp::R_X86_64_PC32_BND
4672            && r_type != elfcpp::R_X86_64_PC32)
4673           || gsym == NULL
4674           || strcmp(gsym->name(), "__tls_get_addr") != 0)
4675         {
4676           gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
4677                                  _("missing expected TLS relocation"));
4678           this->skip_call_tls_get_addr_ = false;
4679         }
4680       else
4681         {
4682           this->skip_call_tls_get_addr_ = false;
4683           return false;
4684         }
4685     }
4686
4687   if (view == NULL)
4688     return true;
4689
4690   const Sized_relobj_file<size, false>* object = relinfo->object;
4691
4692   // Pick the value to use for symbols defined in the PLT.
4693   Symbol_value<size> symval;
4694   if (gsym != NULL
4695       && gsym->use_plt_offset(Scan::get_reference_flags(r_type)))
4696     {
4697       symval.set_output_value(target->plt_address_for_global(gsym));
4698       psymval = &symval;
4699     }
4700   else if (gsym == NULL && psymval->is_ifunc_symbol())
4701     {
4702       unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
4703       if (object->local_has_plt_offset(r_sym))
4704         {
4705           symval.set_output_value(target->plt_address_for_local(object, r_sym));
4706           psymval = &symval;
4707         }
4708     }
4709
4710   const elfcpp::Elf_Xword addend = rela.get_r_addend();
4711
4712   // Get the GOT offset if needed.
4713   // The GOT pointer points to the end of the GOT section.
4714   // We need to subtract the size of the GOT section to get
4715   // the actual offset to use in the relocation.
4716   bool have_got_offset = false;
4717   // Since the actual offset is always negative, we use signed int to
4718   // support 64-bit GOT relocations.
4719   int got_offset = 0;
4720   switch (r_type)
4721     {
4722     case elfcpp::R_X86_64_GOT32:
4723     case elfcpp::R_X86_64_GOT64:
4724     case elfcpp::R_X86_64_GOTPLT64:
4725     case elfcpp::R_X86_64_GOTPCREL64:
4726       if (gsym != NULL)
4727         {
4728           gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
4729           got_offset = gsym->got_offset(GOT_TYPE_STANDARD) - target->got_size();
4730         }
4731       else
4732         {
4733           unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
4734           gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD));
4735           got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD)
4736                         - target->got_size());
4737         }
4738       have_got_offset = true;
4739       break;
4740
4741     default:
4742       break;
4743     }
4744
4745   typename Reloc_funcs::Reloc_status rstatus = Reloc_funcs::RELOC_OK;
4746
4747   switch (r_type)
4748     {
4749     case elfcpp::R_X86_64_NONE:
4750     case elfcpp::R_X86_64_GNU_VTINHERIT:
4751     case elfcpp::R_X86_64_GNU_VTENTRY:
4752       break;
4753
4754     case elfcpp::R_X86_64_64:
4755       Reloc_funcs::rela64(view, object, psymval, addend);
4756       break;
4757
4758     case elfcpp::R_X86_64_PC64:
4759       Reloc_funcs::pcrela64(view, object, psymval, addend,
4760                                               address);
4761       break;
4762
4763     case elfcpp::R_X86_64_32:
4764       rstatus = Reloc_funcs::rela32_check(view, object, psymval, addend,
4765                                           Reloc_funcs::CHECK_UNSIGNED);
4766       break;
4767
4768     case elfcpp::R_X86_64_32S:
4769       rstatus = Reloc_funcs::rela32_check(view, object, psymval, addend,
4770                                           Reloc_funcs::CHECK_SIGNED);
4771       break;
4772
4773     case elfcpp::R_X86_64_PC32:
4774     case elfcpp::R_X86_64_PC32_BND:
4775       rstatus = Reloc_funcs::pcrela32_check(view, object, psymval, addend,
4776                                             address);
4777       break;
4778
4779     case elfcpp::R_X86_64_16:
4780       Reloc_funcs::rela16(view, object, psymval, addend);
4781       break;
4782
4783     case elfcpp::R_X86_64_PC16:
4784       Reloc_funcs::pcrela16(view, object, psymval, addend, address);
4785       break;
4786
4787     case elfcpp::R_X86_64_8:
4788       Reloc_funcs::rela8(view, object, psymval, addend);
4789       break;
4790
4791     case elfcpp::R_X86_64_PC8:
4792       Reloc_funcs::pcrela8(view, object, psymval, addend, address);
4793       break;
4794
4795     case elfcpp::R_X86_64_PLT32:
4796     case elfcpp::R_X86_64_PLT32_BND:
4797       gold_assert(gsym == NULL
4798                   || gsym->has_plt_offset()
4799                   || gsym->final_value_is_known()
4800                   || (gsym->is_defined()
4801                       && !gsym->is_from_dynobj()
4802                       && !gsym->is_preemptible()));
4803       // Note: while this code looks the same as for R_X86_64_PC32, it
4804       // behaves differently because psymval was set to point to
4805       // the PLT entry, rather than the symbol, in Scan::global().
4806       rstatus = Reloc_funcs::pcrela32_check(view, object, psymval, addend,
4807                                             address);
4808       break;
4809
4810     case elfcpp::R_X86_64_PLTOFF64:
4811       {
4812         gold_assert(gsym);
4813         gold_assert(gsym->has_plt_offset()
4814                     || gsym->final_value_is_known());
4815         typename elfcpp::Elf_types<size>::Elf_Addr got_address;
4816         // This is the address of GLOBAL_OFFSET_TABLE.
4817         got_address = target->got_plt_section()->address();
4818         Reloc_funcs::rela64(view, object, psymval, addend - got_address);
4819       }
4820       break;
4821
4822     case elfcpp::R_X86_64_GOT32:
4823       gold_assert(have_got_offset);
4824       Reloc_funcs::rela32(view, got_offset, addend);
4825       break;
4826
4827     case elfcpp::R_X86_64_GOTPC32:
4828       {
4829         gold_assert(gsym);
4830         typename elfcpp::Elf_types<size>::Elf_Addr value;
4831         value = target->got_plt_section()->address();
4832         Reloc_funcs::pcrela32_check(view, value, addend, address);
4833       }
4834       break;
4835
4836     case elfcpp::R_X86_64_GOT64:
4837     case elfcpp::R_X86_64_GOTPLT64:
4838       // R_X86_64_GOTPLT64 is obsolete and treated the same as
4839       // GOT64.
4840       gold_assert(have_got_offset);
4841       Reloc_funcs::rela64(view, got_offset, addend);
4842       break;
4843
4844     case elfcpp::R_X86_64_GOTPC64:
4845       {
4846         gold_assert(gsym);
4847         typename elfcpp::Elf_types<size>::Elf_Addr value;
4848         value = target->got_plt_section()->address();
4849         Reloc_funcs::pcrela64(view, value, addend, address);
4850       }
4851       break;
4852
4853     case elfcpp::R_X86_64_GOTOFF64:
4854       {
4855         typename elfcpp::Elf_types<size>::Elf_Addr value;
4856         value = (psymval->value(object, 0)
4857                  - target->got_plt_section()->address());
4858         Reloc_funcs::rela64(view, value, addend);
4859       }
4860       break;
4861
4862     case elfcpp::R_X86_64_GOTPCREL:
4863     case elfcpp::R_X86_64_GOTPCRELX:
4864     case elfcpp::R_X86_64_REX_GOTPCRELX:
4865       {
4866       // Convert
4867       // mov foo@GOTPCREL(%rip), %reg
4868       // to lea foo(%rip), %reg.
4869       // if possible.
4870       if (!parameters->incremental()
4871           && ((gsym == NULL
4872                && rela.get_r_offset() >= 2
4873                && view[-2] == 0x8b
4874                && !psymval->is_ifunc_symbol())
4875               || (gsym != NULL
4876                   && rela.get_r_offset() >= 2
4877                   && Target_x86_64<size>::can_convert_mov_to_lea(gsym, r_type,
4878                                                                  0, &view))))
4879         {
4880           view[-2] = 0x8d;
4881           Reloc_funcs::pcrela32(view, object, psymval, addend, address);
4882         }
4883       // Convert
4884       // callq *foo@GOTPCRELX(%rip) to
4885       // addr32 callq foo
4886       // and jmpq *foo@GOTPCRELX(%rip) to
4887       // jmpq foo
4888       // nop
4889       else if (!parameters->incremental()
4890                && gsym != NULL
4891                && rela.get_r_offset() >= 2
4892                && Target_x86_64<size>::can_convert_callq_to_direct(gsym,
4893                                                                    r_type,
4894                                                                    0, &view))
4895         {
4896           if (view[-1] == 0x15)
4897             {
4898               // Convert callq *foo@GOTPCRELX(%rip) to addr32 callq.
4899               // Opcode of addr32 is 0x67 and opcode of direct callq is 0xe8.
4900               view[-2] = 0x67;
4901               view[-1] = 0xe8;
4902               // Convert GOTPCRELX to 32-bit pc relative reloc.
4903               Reloc_funcs::pcrela32(view, object, psymval, addend, address);
4904             }
4905           else
4906             {
4907               // Convert jmpq *foo@GOTPCRELX(%rip) to
4908               // jmpq foo
4909               // nop
4910               // The opcode of direct jmpq is 0xe9.
4911               view[-2] = 0xe9;
4912               // The opcode of nop is 0x90.
4913               view[3] = 0x90;
4914               // Convert GOTPCRELX to 32-bit pc relative reloc.  jmpq is rip
4915               // relative and since the instruction following the jmpq is now
4916               // the nop, offset the address by 1 byte.  The start of the
4917               // relocation also moves ahead by 1 byte.
4918               Reloc_funcs::pcrela32(&view[-1], object, psymval, addend,
4919                                     address - 1);
4920             }
4921         }
4922       else
4923         {
4924           if (gsym != NULL)
4925             {
4926               gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
4927               got_offset = (gsym->got_offset(GOT_TYPE_STANDARD)
4928                             - target->got_size());
4929             }
4930           else
4931             {
4932               unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
4933               gold_assert(object->local_has_got_offset(r_sym,
4934                                                        GOT_TYPE_STANDARD));
4935               got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD)
4936                             - target->got_size());
4937             }
4938           typename elfcpp::Elf_types<size>::Elf_Addr value;
4939           value = target->got_plt_section()->address() + got_offset;
4940           Reloc_funcs::pcrela32_check(view, value, addend, address);
4941         }
4942       }
4943       break;
4944
4945     case elfcpp::R_X86_64_GOTPCREL64:
4946       {
4947         gold_assert(have_got_offset);
4948         typename elfcpp::Elf_types<size>::Elf_Addr value;
4949         value = target->got_plt_section()->address() + got_offset;
4950         Reloc_funcs::pcrela64(view, value, addend, address);
4951       }
4952       break;
4953
4954     case elfcpp::R_X86_64_COPY:
4955     case elfcpp::R_X86_64_GLOB_DAT:
4956     case elfcpp::R_X86_64_JUMP_SLOT:
4957     case elfcpp::R_X86_64_RELATIVE:
4958     case elfcpp::R_X86_64_IRELATIVE:
4959       // These are outstanding tls relocs, which are unexpected when linking
4960     case elfcpp::R_X86_64_TPOFF64:
4961     case elfcpp::R_X86_64_DTPMOD64:
4962     case elfcpp::R_X86_64_TLSDESC:
4963       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
4964                              _("unexpected reloc %u in object file"),
4965                              r_type);
4966       break;
4967
4968       // These are initial tls relocs, which are expected when linking
4969     case elfcpp::R_X86_64_TLSGD:            // Global-dynamic
4970     case elfcpp::R_X86_64_GOTPC32_TLSDESC:  // Global-dynamic (from ~oliva url)
4971     case elfcpp::R_X86_64_TLSDESC_CALL:
4972     case elfcpp::R_X86_64_TLSLD:            // Local-dynamic
4973     case elfcpp::R_X86_64_DTPOFF32:
4974     case elfcpp::R_X86_64_DTPOFF64:
4975     case elfcpp::R_X86_64_GOTTPOFF:         // Initial-exec
4976     case elfcpp::R_X86_64_TPOFF32:          // Local-exec
4977       this->relocate_tls(relinfo, target, relnum, rela, r_type, gsym, psymval,
4978                          view, address, view_size);
4979       break;
4980
4981     case elfcpp::R_X86_64_SIZE32:
4982     case elfcpp::R_X86_64_SIZE64:
4983     default:
4984       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
4985                              _("unsupported reloc %u"),
4986                              r_type);
4987       break;
4988     }
4989
4990   if (rstatus == Reloc_funcs::RELOC_OVERFLOW)
4991     {
4992       if (gsym == NULL)
4993         {
4994           unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
4995           gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
4996                                  _("relocation overflow: "
4997                                    "reference to local symbol %u in %s"),
4998                                  r_sym, object->name().c_str());
4999         }
5000       else if (gsym->is_defined() && gsym->source() == Symbol::FROM_OBJECT)
5001         {
5002           gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
5003                                  _("relocation overflow: "
5004                                    "reference to '%s' defined in %s"),
5005                                  gsym->name(),
5006                                  gsym->object()->name().c_str());
5007         }
5008       else
5009         {
5010           gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
5011                                  _("relocation overflow: reference to '%s'"),
5012                                  gsym->name());
5013         }
5014     }
5015
5016   return true;
5017 }
5018
5019 // Perform a TLS relocation.
5020
5021 template<int size>
5022 inline void
5023 Target_x86_64<size>::Relocate::relocate_tls(
5024     const Relocate_info<size, false>* relinfo,
5025     Target_x86_64<size>* target,
5026     size_t relnum,
5027     const elfcpp::Rela<size, false>& rela,
5028     unsigned int r_type,
5029     const Sized_symbol<size>* gsym,
5030     const Symbol_value<size>* psymval,
5031     unsigned char* view,
5032     typename elfcpp::Elf_types<size>::Elf_Addr address,
5033     section_size_type view_size)
5034 {
5035   Output_segment* tls_segment = relinfo->layout->tls_segment();
5036
5037   const Sized_relobj_file<size, false>* object = relinfo->object;
5038   const elfcpp::Elf_Xword addend = rela.get_r_addend();
5039   elfcpp::Shdr<size, false> data_shdr(relinfo->data_shdr);
5040   bool is_executable = (data_shdr.get_sh_flags() & elfcpp::SHF_EXECINSTR) != 0;
5041
5042   typename elfcpp::Elf_types<size>::Elf_Addr value = psymval->value(relinfo->object, 0);
5043
5044   const bool is_final = (gsym == NULL
5045                          ? !parameters->options().shared()
5046                          : gsym->final_value_is_known());
5047   tls::Tls_optimization optimized_type
5048       = Target_x86_64<size>::optimize_tls_reloc(is_final, r_type);
5049   switch (r_type)
5050     {
5051     case elfcpp::R_X86_64_TLSGD:            // Global-dynamic
5052       if (!is_executable && optimized_type == tls::TLSOPT_TO_LE)
5053         {
5054           // If this code sequence is used in a non-executable section,
5055           // we will not optimize the R_X86_64_DTPOFF32/64 relocation,
5056           // on the assumption that it's being used by itself in a debug
5057           // section.  Therefore, in the unlikely event that the code
5058           // sequence appears in a non-executable section, we simply
5059           // leave it unoptimized.
5060           optimized_type = tls::TLSOPT_NONE;
5061         }
5062       if (optimized_type == tls::TLSOPT_TO_LE)
5063         {
5064           if (tls_segment == NULL)
5065             {
5066               gold_assert(parameters->errors()->error_count() > 0
5067                           || issue_undefined_symbol_error(gsym));
5068               return;
5069             }
5070           this->tls_gd_to_le(relinfo, relnum, tls_segment,
5071                              rela, r_type, value, view,
5072                              view_size);
5073           break;
5074         }
5075       else
5076         {
5077           unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE
5078                                    ? GOT_TYPE_TLS_OFFSET
5079                                    : GOT_TYPE_TLS_PAIR);
5080           unsigned int got_offset;
5081           if (gsym != NULL)
5082             {
5083               gold_assert(gsym->has_got_offset(got_type));
5084               got_offset = gsym->got_offset(got_type) - target->got_size();
5085             }
5086           else
5087             {
5088               unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
5089               gold_assert(object->local_has_got_offset(r_sym, got_type));
5090               got_offset = (object->local_got_offset(r_sym, got_type)
5091                             - target->got_size());
5092             }
5093           if (optimized_type == tls::TLSOPT_TO_IE)
5094             {
5095               value = target->got_plt_section()->address() + got_offset;
5096               this->tls_gd_to_ie(relinfo, relnum, rela, r_type,
5097                                  value, view, address, view_size);
5098               break;
5099             }
5100           else if (optimized_type == tls::TLSOPT_NONE)
5101             {
5102               // Relocate the field with the offset of the pair of GOT
5103               // entries.
5104               value = target->got_plt_section()->address() + got_offset;
5105               Relocate_functions<size, false>::pcrela32(view, value, addend,
5106                                                         address);
5107               break;
5108             }
5109         }
5110       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
5111                              _("unsupported reloc %u"), r_type);
5112       break;
5113
5114     case elfcpp::R_X86_64_GOTPC32_TLSDESC:  // Global-dynamic (from ~oliva url)
5115     case elfcpp::R_X86_64_TLSDESC_CALL:
5116       if (!is_executable && optimized_type == tls::TLSOPT_TO_LE)
5117         {
5118           // See above comment for R_X86_64_TLSGD.
5119           optimized_type = tls::TLSOPT_NONE;
5120         }
5121       if (optimized_type == tls::TLSOPT_TO_LE)
5122         {
5123           if (tls_segment == NULL)
5124             {
5125               gold_assert(parameters->errors()->error_count() > 0
5126                           || issue_undefined_symbol_error(gsym));
5127               return;
5128             }
5129           this->tls_desc_gd_to_le(relinfo, relnum, tls_segment,
5130                                   rela, r_type, value, view,
5131                                   view_size);
5132           break;
5133         }
5134       else
5135         {
5136           unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE
5137                                    ? GOT_TYPE_TLS_OFFSET
5138                                    : GOT_TYPE_TLS_DESC);
5139           unsigned int got_offset = 0;
5140           if (r_type == elfcpp::R_X86_64_GOTPC32_TLSDESC
5141               && optimized_type == tls::TLSOPT_NONE)
5142             {
5143               // We created GOT entries in the .got.tlsdesc portion of
5144               // the .got.plt section, but the offset stored in the
5145               // symbol is the offset within .got.tlsdesc.
5146               got_offset = (target->got_size()
5147                             + target->got_plt_section()->data_size());
5148             }
5149           if (gsym != NULL)
5150             {
5151               gold_assert(gsym->has_got_offset(got_type));
5152               got_offset += gsym->got_offset(got_type) - target->got_size();
5153             }
5154           else
5155             {
5156               unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
5157               gold_assert(object->local_has_got_offset(r_sym, got_type));
5158               got_offset += (object->local_got_offset(r_sym, got_type)
5159                              - target->got_size());
5160             }
5161           if (optimized_type == tls::TLSOPT_TO_IE)
5162             {
5163               value = target->got_plt_section()->address() + got_offset;
5164               this->tls_desc_gd_to_ie(relinfo, relnum,
5165                                       rela, r_type, value, view, address,
5166                                       view_size);
5167               break;
5168             }
5169           else if (optimized_type == tls::TLSOPT_NONE)
5170             {
5171               if (r_type == elfcpp::R_X86_64_GOTPC32_TLSDESC)
5172                 {
5173                   // Relocate the field with the offset of the pair of GOT
5174                   // entries.
5175                   value = target->got_plt_section()->address() + got_offset;
5176                   Relocate_functions<size, false>::pcrela32(view, value, addend,
5177                                                             address);
5178                 }
5179               break;
5180             }
5181         }
5182       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
5183                              _("unsupported reloc %u"), r_type);
5184       break;
5185
5186     case elfcpp::R_X86_64_TLSLD:            // Local-dynamic
5187       if (!is_executable && optimized_type == tls::TLSOPT_TO_LE)
5188         {
5189           // See above comment for R_X86_64_TLSGD.
5190           optimized_type = tls::TLSOPT_NONE;
5191         }
5192       if (optimized_type == tls::TLSOPT_TO_LE)
5193         {
5194           if (tls_segment == NULL)
5195             {
5196               gold_assert(parameters->errors()->error_count() > 0
5197                           || issue_undefined_symbol_error(gsym));
5198               return;
5199             }
5200           this->tls_ld_to_le(relinfo, relnum, tls_segment, rela, r_type,
5201                              value, view, view_size);
5202           break;
5203         }
5204       else if (optimized_type == tls::TLSOPT_NONE)
5205         {
5206           // Relocate the field with the offset of the GOT entry for
5207           // the module index.
5208           unsigned int got_offset;
5209           got_offset = (target->got_mod_index_entry(NULL, NULL, NULL)
5210                         - target->got_size());
5211           value = target->got_plt_section()->address() + got_offset;
5212           Relocate_functions<size, false>::pcrela32(view, value, addend,
5213                                                     address);
5214           break;
5215         }
5216       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
5217                              _("unsupported reloc %u"), r_type);
5218       break;
5219
5220     case elfcpp::R_X86_64_DTPOFF32:
5221       // This relocation type is used in debugging information.
5222       // In that case we need to not optimize the value.  If the
5223       // section is not executable, then we assume we should not
5224       // optimize this reloc.  See comments above for R_X86_64_TLSGD,
5225       // R_X86_64_GOTPC32_TLSDESC, R_X86_64_TLSDESC_CALL, and
5226       // R_X86_64_TLSLD.
5227       if (optimized_type == tls::TLSOPT_TO_LE && is_executable)
5228         {
5229           if (tls_segment == NULL)
5230             {
5231               gold_assert(parameters->errors()->error_count() > 0
5232                           || issue_undefined_symbol_error(gsym));
5233               return;
5234             }
5235           value -= tls_segment->memsz();
5236         }
5237       Relocate_functions<size, false>::rela32(view, value, addend);
5238       break;
5239
5240     case elfcpp::R_X86_64_DTPOFF64:
5241       // See R_X86_64_DTPOFF32, just above, for why we check for is_executable.
5242       if (optimized_type == tls::TLSOPT_TO_LE && is_executable)
5243         {
5244           if (tls_segment == NULL)
5245             {
5246               gold_assert(parameters->errors()->error_count() > 0
5247                           || issue_undefined_symbol_error(gsym));
5248               return;
5249             }
5250           value -= tls_segment->memsz();
5251         }
5252       Relocate_functions<size, false>::rela64(view, value, addend);
5253       break;
5254
5255     case elfcpp::R_X86_64_GOTTPOFF:         // Initial-exec
5256       if (gsym != NULL
5257           && gsym->is_undefined()
5258           && parameters->options().output_is_executable())
5259         {
5260           Target_x86_64<size>::Relocate::tls_ie_to_le(relinfo, relnum,
5261                                                       NULL, rela,
5262                                                       r_type, value, view,
5263                                                       view_size);
5264           break;
5265         }
5266       else if (optimized_type == tls::TLSOPT_TO_LE)
5267         {
5268           if (tls_segment == NULL)
5269             {
5270               gold_assert(parameters->errors()->error_count() > 0
5271                           || issue_undefined_symbol_error(gsym));
5272               return;
5273             }
5274           Target_x86_64<size>::Relocate::tls_ie_to_le(relinfo, relnum,
5275                                                       tls_segment, rela,
5276                                                       r_type, value, view,
5277                                                       view_size);
5278           break;
5279         }
5280       else if (optimized_type == tls::TLSOPT_NONE)
5281         {
5282           // Relocate the field with the offset of the GOT entry for
5283           // the tp-relative offset of the symbol.
5284           unsigned int got_offset;
5285           if (gsym != NULL)
5286             {
5287               gold_assert(gsym->has_got_offset(GOT_TYPE_TLS_OFFSET));
5288               got_offset = (gsym->got_offset(GOT_TYPE_TLS_OFFSET)
5289                             - target->got_size());
5290             }
5291           else
5292             {
5293               unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
5294               gold_assert(object->local_has_got_offset(r_sym,
5295                                                        GOT_TYPE_TLS_OFFSET));
5296               got_offset = (object->local_got_offset(r_sym, GOT_TYPE_TLS_OFFSET)
5297                             - target->got_size());
5298             }
5299           value = target->got_plt_section()->address() + got_offset;
5300           Relocate_functions<size, false>::pcrela32(view, value, addend,
5301                                                     address);
5302           break;
5303         }
5304       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
5305                              _("unsupported reloc type %u"),
5306                              r_type);
5307       break;
5308
5309     case elfcpp::R_X86_64_TPOFF32:          // Local-exec
5310       if (tls_segment == NULL)
5311         {
5312           gold_assert(parameters->errors()->error_count() > 0
5313                       || issue_undefined_symbol_error(gsym));
5314           return;
5315         }
5316       value -= tls_segment->memsz();
5317       Relocate_functions<size, false>::rela32(view, value, addend);
5318       break;
5319     }
5320 }
5321
5322 // Do a relocation in which we convert a TLS General-Dynamic to an
5323 // Initial-Exec.
5324
5325 template<int size>
5326 inline void
5327 Target_x86_64<size>::Relocate::tls_gd_to_ie(
5328     const Relocate_info<size, false>* relinfo,
5329     size_t relnum,
5330     const elfcpp::Rela<size, false>& rela,
5331     unsigned int,
5332     typename elfcpp::Elf_types<size>::Elf_Addr value,
5333     unsigned char* view,
5334     typename elfcpp::Elf_types<size>::Elf_Addr address,
5335     section_size_type view_size)
5336 {
5337   // For SIZE == 64:
5338   //    .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
5339   //    .word 0x6666; rex64; call __tls_get_addr@PLT
5340   //    ==> movq %fs:0,%rax; addq x@gottpoff(%rip),%rax
5341   //    .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
5342   //    .word 0x66; rex64; call *__tls_get_addr@GOTPCREL(%rip)
5343   //    ==> movq %fs:0,%rax; addq x@gottpoff(%rip),%rax
5344   // For SIZE == 32:
5345   //    leaq foo@tlsgd(%rip),%rdi;
5346   //    .word 0x6666; rex64; call __tls_get_addr@PLT
5347   //    ==> movl %fs:0,%eax; addq x@gottpoff(%rip),%rax
5348   //    leaq foo@tlsgd(%rip),%rdi;
5349   //    .word 0x66; rex64; call *__tls_get_addr@GOTPCREL(%rip)
5350   //    ==> movl %fs:0,%eax; addq x@gottpoff(%rip),%rax
5351
5352   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 12);
5353   tls::check_tls(relinfo, relnum, rela.get_r_offset(),
5354                  (memcmp(view + 4, "\x66\x66\x48\xe8", 4) == 0
5355                   || memcmp(view + 4, "\x66\x48\xff", 3) == 0));
5356
5357   if (size == 64)
5358     {
5359       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size,
5360                        -4);
5361       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
5362                      (memcmp(view - 4, "\x66\x48\x8d\x3d", 4) == 0));
5363       memcpy(view - 4, "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x03\x05\0\0\0\0",
5364              16);
5365     }
5366   else
5367     {
5368       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size,
5369                        -3);
5370       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
5371                      (memcmp(view - 3, "\x48\x8d\x3d", 3) == 0));
5372       memcpy(view - 3, "\x64\x8b\x04\x25\0\0\0\0\x48\x03\x05\0\0\0\0",
5373              15);
5374     }
5375
5376   const elfcpp::Elf_Xword addend = rela.get_r_addend();
5377   Relocate_functions<size, false>::pcrela32(view + 8, value, addend - 8,
5378                                             address);
5379
5380   // The next reloc should be a PLT32 reloc against __tls_get_addr.
5381   // We can skip it.
5382   this->skip_call_tls_get_addr_ = true;
5383 }
5384
5385 // Do a relocation in which we convert a TLS General-Dynamic to a
5386 // Local-Exec.
5387
5388 template<int size>
5389 inline void
5390 Target_x86_64<size>::Relocate::tls_gd_to_le(
5391     const Relocate_info<size, false>* relinfo,
5392     size_t relnum,
5393     Output_segment* tls_segment,
5394     const elfcpp::Rela<size, false>& rela,
5395     unsigned int,
5396     typename elfcpp::Elf_types<size>::Elf_Addr value,
5397     unsigned char* view,
5398     section_size_type view_size)
5399 {
5400   // For SIZE == 64:
5401   //    .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
5402   //    .word 0x6666; rex64; call __tls_get_addr@PLT
5403   //    ==> movq %fs:0,%rax; leaq x@tpoff(%rax),%rax
5404   //    .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
5405   //    .word 0x66; rex64; call *__tls_get_addr@GOTPCREL(%rip)
5406   //    ==> movq %fs:0,%rax; leaq x@tpoff(%rax),%rax
5407   // For SIZE == 32:
5408   //    leaq foo@tlsgd(%rip),%rdi;
5409   //    .word 0x6666; rex64; call __tls_get_addr@PLT
5410   //    ==> movl %fs:0,%eax; leaq x@tpoff(%rax),%rax
5411   //    leaq foo@tlsgd(%rip),%rdi;
5412   //    .word 0x66; rex64; call *__tls_get_addr@GOTPCREL(%rip)
5413   //    ==> movl %fs:0,%eax; leaq x@tpoff(%rax),%rax
5414
5415   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 12);
5416   tls::check_tls(relinfo, relnum, rela.get_r_offset(),
5417                  (memcmp(view + 4, "\x66\x66\x48\xe8", 4) == 0
5418                   || memcmp(view + 4, "\x66\x48\xff", 3) == 0));
5419
5420   if (size == 64)
5421     {
5422       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size,
5423                        -4);
5424       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
5425                      (memcmp(view - 4, "\x66\x48\x8d\x3d", 4) == 0));
5426       memcpy(view - 4, "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0\0",
5427              16);
5428     }
5429   else
5430     {
5431       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size,
5432                        -3);
5433       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
5434                      (memcmp(view - 3, "\x48\x8d\x3d", 3) == 0));
5435
5436       memcpy(view - 3, "\x64\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0\0",
5437              15);
5438     }
5439
5440   value -= tls_segment->memsz();
5441   Relocate_functions<size, false>::rela32(view + 8, value, 0);
5442
5443   // The next reloc should be a PLT32 reloc against __tls_get_addr.
5444   // We can skip it.
5445   this->skip_call_tls_get_addr_ = true;
5446 }
5447
5448 // Do a TLSDESC-style General-Dynamic to Initial-Exec transition.
5449
5450 template<int size>
5451 inline void
5452 Target_x86_64<size>::Relocate::tls_desc_gd_to_ie(
5453     const Relocate_info<size, false>* relinfo,
5454     size_t relnum,
5455     const elfcpp::Rela<size, false>& rela,
5456     unsigned int r_type,
5457     typename elfcpp::Elf_types<size>::Elf_Addr value,
5458     unsigned char* view,
5459     typename elfcpp::Elf_types<size>::Elf_Addr address,
5460     section_size_type view_size)
5461 {
5462   if (r_type == elfcpp::R_X86_64_GOTPC32_TLSDESC)
5463     {
5464       // leaq foo@tlsdesc(%rip), %rax
5465       // ==> movq foo@gottpoff(%rip), %rax
5466       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -3);
5467       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 4);
5468       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
5469                      view[-3] == 0x48 && view[-2] == 0x8d && view[-1] == 0x05);
5470       view[-2] = 0x8b;
5471       const elfcpp::Elf_Xword addend = rela.get_r_addend();
5472       Relocate_functions<size, false>::pcrela32(view, value, addend, address);
5473     }
5474   else
5475     {
5476       // call *foo@tlscall(%rax)
5477       // ==> nop; nop
5478       gold_assert(r_type == elfcpp::R_X86_64_TLSDESC_CALL);
5479       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 2);
5480       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
5481                      view[0] == 0xff && view[1] == 0x10);
5482       view[0] = 0x66;
5483       view[1] = 0x90;
5484     }
5485 }
5486
5487 // Do a TLSDESC-style General-Dynamic to Local-Exec transition.
5488
5489 template<int size>
5490 inline void
5491 Target_x86_64<size>::Relocate::tls_desc_gd_to_le(
5492     const Relocate_info<size, false>* relinfo,
5493     size_t relnum,
5494     Output_segment* tls_segment,
5495     const elfcpp::Rela<size, false>& rela,
5496     unsigned int r_type,
5497     typename elfcpp::Elf_types<size>::Elf_Addr value,
5498     unsigned char* view,
5499     section_size_type view_size)
5500 {
5501   if (r_type == elfcpp::R_X86_64_GOTPC32_TLSDESC)
5502     {
5503       // leaq foo@tlsdesc(%rip), %rax
5504       // ==> movq foo@tpoff, %rax
5505       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -3);
5506       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 4);
5507       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
5508                      view[-3] == 0x48 && view[-2] == 0x8d && view[-1] == 0x05);
5509       view[-2] = 0xc7;
5510       view[-1] = 0xc0;
5511       value -= tls_segment->memsz();
5512       Relocate_functions<size, false>::rela32(view, value, 0);
5513     }
5514   else
5515     {
5516       // call *foo@tlscall(%rax)
5517       // ==> nop; nop
5518       gold_assert(r_type == elfcpp::R_X86_64_TLSDESC_CALL);
5519       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 2);
5520       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
5521                      view[0] == 0xff && view[1] == 0x10);
5522       view[0] = 0x66;
5523       view[1] = 0x90;
5524     }
5525 }
5526
5527 template<int size>
5528 inline void
5529 Target_x86_64<size>::Relocate::tls_ld_to_le(
5530     const Relocate_info<size, false>* relinfo,
5531     size_t relnum,
5532     Output_segment*,
5533     const elfcpp::Rela<size, false>& rela,
5534     unsigned int,
5535     typename elfcpp::Elf_types<size>::Elf_Addr,
5536     unsigned char* view,
5537     section_size_type view_size)
5538 {
5539   // leaq foo@tlsld(%rip),%rdi; call __tls_get_addr@plt;
5540   // For SIZE == 64:
5541   // ... leq foo@dtpoff(%rax),%reg
5542   // ==> .word 0x6666; .byte 0x66; movq %fs:0,%rax ... leaq x@tpoff(%rax),%rdx
5543   // For SIZE == 32:
5544   // ... leq foo@dtpoff(%rax),%reg
5545   // ==> nopl 0x0(%rax); movl %fs:0,%eax ... leaq x@tpoff(%rax),%rdx
5546   // leaq foo@tlsld(%rip),%rdi; call *__tls_get_addr@GOTPCREL(%rip)
5547   // For SIZE == 64:
5548   // ... leq foo@dtpoff(%rax),%reg
5549   // ==> .word 0x6666; .byte 0x6666; movq %fs:0,%rax ... leaq x@tpoff(%rax),%rdx
5550   // For SIZE == 32:
5551   // ... leq foo@dtpoff(%rax),%reg
5552   // ==> nopw 0x0(%rax); movl %fs:0,%eax ... leaq x@tpoff(%rax),%rdx
5553
5554   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -3);
5555   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 9);
5556
5557   tls::check_tls(relinfo, relnum, rela.get_r_offset(),
5558                  view[-3] == 0x48 && view[-2] == 0x8d && view[-1] == 0x3d);
5559
5560   tls::check_tls(relinfo, relnum, rela.get_r_offset(),
5561                  view[4] == 0xe8 || view[4] == 0xff);
5562
5563   if (view[4] == 0xe8)
5564     {
5565       if (size == 64)
5566         memcpy(view - 3, "\x66\x66\x66\x64\x48\x8b\x04\x25\0\0\0\0", 12);
5567       else
5568         memcpy(view - 3, "\x0f\x1f\x40\x00\x64\x8b\x04\x25\0\0\0\0", 12);
5569     }
5570   else
5571     {
5572       if (size == 64)
5573         memcpy(view - 3, "\x66\x66\x66\x66\x64\x48\x8b\x04\x25\0\0\0\0",
5574                13);
5575       else
5576         memcpy(view - 3, "\x66\x0f\x1f\x40\x00\x64\x8b\x04\x25\0\0\0\0",
5577                13);
5578     }
5579
5580   // The next reloc should be a PLT32 reloc against __tls_get_addr.
5581   // We can skip it.
5582   this->skip_call_tls_get_addr_ = true;
5583 }
5584
5585 // Do a relocation in which we convert a TLS Initial-Exec to a
5586 // Local-Exec.
5587
5588 template<int size>
5589 inline void
5590 Target_x86_64<size>::Relocate::tls_ie_to_le(
5591     const Relocate_info<size, false>* relinfo,
5592     size_t relnum,
5593     Output_segment* tls_segment,
5594     const elfcpp::Rela<size, false>& rela,
5595     unsigned int,
5596     typename elfcpp::Elf_types<size>::Elf_Addr value,
5597     unsigned char* view,
5598     section_size_type view_size)
5599 {
5600   // We need to examine the opcodes to figure out which instruction we
5601   // are looking at.
5602
5603   // movq foo@gottpoff(%rip),%reg  ==>  movq $YY,%reg
5604   // addq foo@gottpoff(%rip),%reg  ==>  addq $YY,%reg
5605
5606   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -3);
5607   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 4);
5608
5609   unsigned char op1 = view[-3];
5610   unsigned char op2 = view[-2];
5611   unsigned char op3 = view[-1];
5612   unsigned char reg = op3 >> 3;
5613
5614   if (op2 == 0x8b)
5615     {
5616       // movq
5617       if (op1 == 0x4c)
5618         view[-3] = 0x49;
5619       else if (size == 32 && op1 == 0x44)
5620         view[-3] = 0x41;
5621       view[-2] = 0xc7;
5622       view[-1] = 0xc0 | reg;
5623     }
5624   else if (reg == 4)
5625     {
5626       // Special handling for %rsp.
5627       if (op1 == 0x4c)
5628         view[-3] = 0x49;
5629       else if (size == 32 && op1 == 0x44)
5630         view[-3] = 0x41;
5631       view[-2] = 0x81;
5632       view[-1] = 0xc0 | reg;
5633     }
5634   else
5635     {
5636       // addq
5637       if (op1 == 0x4c)
5638         view[-3] = 0x4d;
5639       else if (size == 32 && op1 == 0x44)
5640         view[-3] = 0x45;
5641       view[-2] = 0x8d;
5642       view[-1] = 0x80 | reg | (reg << 3);
5643     }
5644
5645   if (tls_segment != NULL)
5646     value -= tls_segment->memsz();
5647   Relocate_functions<size, false>::rela32(view, value, 0);
5648 }
5649
5650 // Relocate section data.
5651
5652 template<int size>
5653 void
5654 Target_x86_64<size>::relocate_section(
5655     const Relocate_info<size, false>* relinfo,
5656     unsigned int sh_type,
5657     const unsigned char* prelocs,
5658     size_t reloc_count,
5659     Output_section* output_section,
5660     bool needs_special_offset_handling,
5661     unsigned char* view,
5662     typename elfcpp::Elf_types<size>::Elf_Addr address,
5663     section_size_type view_size,
5664     const Reloc_symbol_changes* reloc_symbol_changes)
5665 {
5666   typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, false>
5667       Classify_reloc;
5668
5669   gold_assert(sh_type == elfcpp::SHT_RELA);
5670
5671   gold::relocate_section<size, false, Target_x86_64<size>, Relocate,
5672                          gold::Default_comdat_behavior, Classify_reloc>(
5673     relinfo,
5674     this,
5675     prelocs,
5676     reloc_count,
5677     output_section,
5678     needs_special_offset_handling,
5679     view,
5680     address,
5681     view_size,
5682     reloc_symbol_changes);
5683 }
5684
5685 // Apply an incremental relocation.  Incremental relocations always refer
5686 // to global symbols.
5687
5688 template<int size>
5689 void
5690 Target_x86_64<size>::apply_relocation(
5691     const Relocate_info<size, false>* relinfo,
5692     typename elfcpp::Elf_types<size>::Elf_Addr r_offset,
5693     unsigned int r_type,
5694     typename elfcpp::Elf_types<size>::Elf_Swxword r_addend,
5695     const Symbol* gsym,
5696     unsigned char* view,
5697     typename elfcpp::Elf_types<size>::Elf_Addr address,
5698     section_size_type view_size)
5699 {
5700   gold::apply_relocation<size, false, Target_x86_64<size>,
5701                          typename Target_x86_64<size>::Relocate>(
5702     relinfo,
5703     this,
5704     r_offset,
5705     r_type,
5706     r_addend,
5707     gsym,
5708     view,
5709     address,
5710     view_size);
5711 }
5712
5713 // Scan the relocs during a relocatable link.
5714
5715 template<int size>
5716 void
5717 Target_x86_64<size>::scan_relocatable_relocs(
5718     Symbol_table* symtab,
5719     Layout* layout,
5720     Sized_relobj_file<size, false>* object,
5721     unsigned int data_shndx,
5722     unsigned int sh_type,
5723     const unsigned char* prelocs,
5724     size_t reloc_count,
5725     Output_section* output_section,
5726     bool needs_special_offset_handling,
5727     size_t local_symbol_count,
5728     const unsigned char* plocal_symbols,
5729     Relocatable_relocs* rr)
5730 {
5731   typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, false>
5732       Classify_reloc;
5733   typedef gold::Default_scan_relocatable_relocs<Classify_reloc>
5734       Scan_relocatable_relocs;
5735
5736   gold_assert(sh_type == elfcpp::SHT_RELA);
5737
5738   gold::scan_relocatable_relocs<size, false, Scan_relocatable_relocs>(
5739     symtab,
5740     layout,
5741     object,
5742     data_shndx,
5743     prelocs,
5744     reloc_count,
5745     output_section,
5746     needs_special_offset_handling,
5747     local_symbol_count,
5748     plocal_symbols,
5749     rr);
5750 }
5751
5752 // Scan the relocs for --emit-relocs.
5753
5754 template<int size>
5755 void
5756 Target_x86_64<size>::emit_relocs_scan(
5757     Symbol_table* symtab,
5758     Layout* layout,
5759     Sized_relobj_file<size, false>* object,
5760     unsigned int data_shndx,
5761     unsigned int sh_type,
5762     const unsigned char* prelocs,
5763     size_t reloc_count,
5764     Output_section* output_section,
5765     bool needs_special_offset_handling,
5766     size_t local_symbol_count,
5767     const unsigned char* plocal_syms,
5768     Relocatable_relocs* rr)
5769 {
5770   typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, false>
5771       Classify_reloc;
5772   typedef gold::Default_emit_relocs_strategy<Classify_reloc>
5773       Emit_relocs_strategy;
5774
5775   gold_assert(sh_type == elfcpp::SHT_RELA);
5776
5777   gold::scan_relocatable_relocs<size, false, Emit_relocs_strategy>(
5778     symtab,
5779     layout,
5780     object,
5781     data_shndx,
5782     prelocs,
5783     reloc_count,
5784     output_section,
5785     needs_special_offset_handling,
5786     local_symbol_count,
5787     plocal_syms,
5788     rr);
5789 }
5790
5791 // Relocate a section during a relocatable link.
5792
5793 template<int size>
5794 void
5795 Target_x86_64<size>::relocate_relocs(
5796     const Relocate_info<size, false>* relinfo,
5797     unsigned int sh_type,
5798     const unsigned char* prelocs,
5799     size_t reloc_count,
5800     Output_section* output_section,
5801     typename elfcpp::Elf_types<size>::Elf_Off offset_in_output_section,
5802     unsigned char* view,
5803     typename elfcpp::Elf_types<size>::Elf_Addr view_address,
5804     section_size_type view_size,
5805     unsigned char* reloc_view,
5806     section_size_type reloc_view_size)
5807 {
5808   typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, false>
5809       Classify_reloc;
5810
5811   gold_assert(sh_type == elfcpp::SHT_RELA);
5812
5813   gold::relocate_relocs<size, false, Classify_reloc>(
5814     relinfo,
5815     prelocs,
5816     reloc_count,
5817     output_section,
5818     offset_in_output_section,
5819     view,
5820     view_address,
5821     view_size,
5822     reloc_view,
5823     reloc_view_size);
5824 }
5825
5826 // Return the value to use for a dynamic which requires special
5827 // treatment.  This is how we support equality comparisons of function
5828 // pointers across shared library boundaries, as described in the
5829 // processor specific ABI supplement.
5830
5831 template<int size>
5832 uint64_t
5833 Target_x86_64<size>::do_dynsym_value(const Symbol* gsym) const
5834 {
5835   gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset());
5836   return this->plt_address_for_global(gsym);
5837 }
5838
5839 // Return a string used to fill a code section with nops to take up
5840 // the specified length.
5841
5842 template<int size>
5843 std::string
5844 Target_x86_64<size>::do_code_fill(section_size_type length) const
5845 {
5846   if (length >= 16)
5847     {
5848       // Build a jmpq instruction to skip over the bytes.
5849       unsigned char jmp[5];
5850       jmp[0] = 0xe9;
5851       elfcpp::Swap_unaligned<32, false>::writeval(jmp + 1, length - 5);
5852       return (std::string(reinterpret_cast<char*>(&jmp[0]), 5)
5853               + std::string(length - 5, static_cast<char>(0x90)));
5854     }
5855
5856   // Nop sequences of various lengths.
5857   const char nop1[1] = { '\x90' };                 // nop
5858   const char nop2[2] = { '\x66', '\x90' };         // xchg %ax %ax
5859   const char nop3[3] = { '\x0f', '\x1f', '\x00' }; // nop (%rax)
5860   const char nop4[4] = { '\x0f', '\x1f', '\x40',   // nop 0(%rax)
5861                          '\x00'};
5862   const char nop5[5] = { '\x0f', '\x1f', '\x44',   // nop 0(%rax,%rax,1)
5863                          '\x00', '\x00' };
5864   const char nop6[6] = { '\x66', '\x0f', '\x1f',   // nopw 0(%rax,%rax,1)
5865                          '\x44', '\x00', '\x00' };
5866   const char nop7[7] = { '\x0f', '\x1f', '\x80',   // nopl 0L(%rax)
5867                          '\x00', '\x00', '\x00',
5868                          '\x00' };
5869   const char nop8[8] = { '\x0f', '\x1f', '\x84',   // nopl 0L(%rax,%rax,1)
5870                          '\x00', '\x00', '\x00',
5871                          '\x00', '\x00' };
5872   const char nop9[9] = { '\x66', '\x0f', '\x1f',   // nopw 0L(%rax,%rax,1)
5873                          '\x84', '\x00', '\x00',
5874                          '\x00', '\x00', '\x00' };
5875   const char nop10[10] = { '\x66', '\x2e', '\x0f', // nopw %cs:0L(%rax,%rax,1)
5876                            '\x1f', '\x84', '\x00',
5877                            '\x00', '\x00', '\x00',
5878                            '\x00' };
5879   const char nop11[11] = { '\x66', '\x66', '\x2e', // data16
5880                            '\x0f', '\x1f', '\x84', // nopw %cs:0L(%rax,%rax,1)
5881                            '\x00', '\x00', '\x00',
5882                            '\x00', '\x00' };
5883   const char nop12[12] = { '\x66', '\x66', '\x66', // data16; data16
5884                            '\x2e', '\x0f', '\x1f', // nopw %cs:0L(%rax,%rax,1)
5885                            '\x84', '\x00', '\x00',
5886                            '\x00', '\x00', '\x00' };
5887   const char nop13[13] = { '\x66', '\x66', '\x66', // data16; data16; data16
5888                            '\x66', '\x2e', '\x0f', // nopw %cs:0L(%rax,%rax,1)
5889                            '\x1f', '\x84', '\x00',
5890                            '\x00', '\x00', '\x00',
5891                            '\x00' };
5892   const char nop14[14] = { '\x66', '\x66', '\x66', // data16; data16; data16
5893                            '\x66', '\x66', '\x2e', // data16
5894                            '\x0f', '\x1f', '\x84', // nopw %cs:0L(%rax,%rax,1)
5895                            '\x00', '\x00', '\x00',
5896                            '\x00', '\x00' };
5897   const char nop15[15] = { '\x66', '\x66', '\x66', // data16; data16; data16
5898                            '\x66', '\x66', '\x66', // data16; data16
5899                            '\x2e', '\x0f', '\x1f', // nopw %cs:0L(%rax,%rax,1)
5900                            '\x84', '\x00', '\x00',
5901                            '\x00', '\x00', '\x00' };
5902
5903   const char* nops[16] = {
5904     NULL,
5905     nop1, nop2, nop3, nop4, nop5, nop6, nop7,
5906     nop8, nop9, nop10, nop11, nop12, nop13, nop14, nop15
5907   };
5908
5909   return std::string(nops[length], length);
5910 }
5911
5912 // Return the addend to use for a target specific relocation.  The
5913 // only target specific relocation is R_X86_64_TLSDESC for a local
5914 // symbol.  We want to set the addend is the offset of the local
5915 // symbol in the TLS segment.
5916
5917 template<int size>
5918 uint64_t
5919 Target_x86_64<size>::do_reloc_addend(void* arg, unsigned int r_type,
5920                                      uint64_t) const
5921 {
5922   gold_assert(r_type == elfcpp::R_X86_64_TLSDESC);
5923   uintptr_t intarg = reinterpret_cast<uintptr_t>(arg);
5924   gold_assert(intarg < this->tlsdesc_reloc_info_.size());
5925   const Tlsdesc_info& ti(this->tlsdesc_reloc_info_[intarg]);
5926   const Symbol_value<size>* psymval = ti.object->local_symbol(ti.r_sym);
5927   gold_assert(psymval->is_tls_symbol());
5928   // The value of a TLS symbol is the offset in the TLS segment.
5929   return psymval->value(ti.object, 0);
5930 }
5931
5932 // Return the value to use for the base of a DW_EH_PE_datarel offset
5933 // in an FDE.  Solaris and SVR4 use DW_EH_PE_datarel because their
5934 // assembler can not write out the difference between two labels in
5935 // different sections, so instead of using a pc-relative value they
5936 // use an offset from the GOT.
5937
5938 template<int size>
5939 uint64_t
5940 Target_x86_64<size>::do_ehframe_datarel_base() const
5941 {
5942   gold_assert(this->global_offset_table_ != NULL);
5943   Symbol* sym = this->global_offset_table_;
5944   Sized_symbol<size>* ssym = static_cast<Sized_symbol<size>*>(sym);
5945   return ssym->value();
5946 }
5947
5948 // FNOFFSET in section SHNDX in OBJECT is the start of a function
5949 // compiled with -fsplit-stack.  The function calls non-split-stack
5950 // code.  We have to change the function so that it always ensures
5951 // that it has enough stack space to run some random function.
5952
5953 static const unsigned char cmp_insn_32[] = { 0x64, 0x3b, 0x24, 0x25 };
5954 static const unsigned char lea_r10_insn_32[] = { 0x44, 0x8d, 0x94, 0x24 };
5955 static const unsigned char lea_r11_insn_32[] = { 0x44, 0x8d, 0x9c, 0x24 };
5956
5957 static const unsigned char cmp_insn_64[] = { 0x64, 0x48, 0x3b, 0x24, 0x25 };
5958 static const unsigned char lea_r10_insn_64[] = { 0x4c, 0x8d, 0x94, 0x24 };
5959 static const unsigned char lea_r11_insn_64[] = { 0x4c, 0x8d, 0x9c, 0x24 };
5960
5961 template<int size>
5962 void
5963 Target_x86_64<size>::do_calls_non_split(Relobj* object, unsigned int shndx,
5964                                         section_offset_type fnoffset,
5965                                         section_size_type fnsize,
5966                                         const unsigned char*,
5967                                         size_t,
5968                                         unsigned char* view,
5969                                         section_size_type view_size,
5970                                         std::string* from,
5971                                         std::string* to) const
5972 {
5973   const char* const cmp_insn = reinterpret_cast<const char*>
5974       (size == 32 ? cmp_insn_32 : cmp_insn_64);
5975   const char* const lea_r10_insn = reinterpret_cast<const char*>
5976       (size == 32 ? lea_r10_insn_32 : lea_r10_insn_64);
5977   const char* const lea_r11_insn = reinterpret_cast<const char*>
5978       (size == 32 ? lea_r11_insn_32 : lea_r11_insn_64);
5979
5980   const size_t cmp_insn_len =
5981       (size == 32 ? sizeof(cmp_insn_32) : sizeof(cmp_insn_64));
5982   const size_t lea_r10_insn_len =
5983       (size == 32 ? sizeof(lea_r10_insn_32) : sizeof(lea_r10_insn_64));
5984   const size_t lea_r11_insn_len =
5985       (size == 32 ? sizeof(lea_r11_insn_32) : sizeof(lea_r11_insn_64));
5986   const size_t nop_len = (size == 32 ? 7 : 8);
5987
5988   // The function starts with a comparison of the stack pointer and a
5989   // field in the TCB.  This is followed by a jump.
5990
5991   // cmp %fs:NN,%rsp
5992   if (this->match_view(view, view_size, fnoffset, cmp_insn, cmp_insn_len)
5993       && fnsize > nop_len + 1)
5994     {
5995       // We will call __morestack if the carry flag is set after this
5996       // comparison.  We turn the comparison into an stc instruction
5997       // and some nops.
5998       view[fnoffset] = '\xf9';
5999       this->set_view_to_nop(view, view_size, fnoffset + 1, nop_len);
6000     }
6001   // lea NN(%rsp),%r10
6002   // lea NN(%rsp),%r11
6003   else if ((this->match_view(view, view_size, fnoffset,
6004                              lea_r10_insn, lea_r10_insn_len)
6005             || this->match_view(view, view_size, fnoffset,
6006                                 lea_r11_insn, lea_r11_insn_len))
6007            && fnsize > 8)
6008     {
6009       // This is loading an offset from the stack pointer for a
6010       // comparison.  The offset is negative, so we decrease the
6011       // offset by the amount of space we need for the stack.  This
6012       // means we will avoid calling __morestack if there happens to
6013       // be plenty of space on the stack already.
6014       unsigned char* pval = view + fnoffset + 4;
6015       uint32_t val = elfcpp::Swap_unaligned<32, false>::readval(pval);
6016       val -= parameters->options().split_stack_adjust_size();
6017       elfcpp::Swap_unaligned<32, false>::writeval(pval, val);
6018     }
6019   else
6020     {
6021       if (!object->has_no_split_stack())
6022         object->error(_("failed to match split-stack sequence at "
6023                         "section %u offset %0zx"),
6024                       shndx, static_cast<size_t>(fnoffset));
6025       return;
6026     }
6027
6028   // We have to change the function so that it calls
6029   // __morestack_non_split instead of __morestack.  The former will
6030   // allocate additional stack space.
6031   *from = "__morestack";
6032   *to = "__morestack_non_split";
6033 }
6034
6035 // The selector for x86_64 object files.  Note this is never instantiated
6036 // directly.  It's only used in Target_selector_x86_64_nacl, below.
6037
6038 template<int size>
6039 class Target_selector_x86_64 : public Target_selector_freebsd
6040 {
6041 public:
6042   Target_selector_x86_64()
6043     : Target_selector_freebsd(elfcpp::EM_X86_64, size, false,
6044                               (size == 64
6045                                ? "elf64-x86-64" : "elf32-x86-64"),
6046                               (size == 64
6047                                ? "elf64-x86-64-freebsd"
6048                                : "elf32-x86-64-freebsd"),
6049                               (size == 64 ? "elf_x86_64" : "elf32_x86_64"))
6050   { }
6051
6052   Target*
6053   do_instantiate_target()
6054   { return new Target_x86_64<size>(); }
6055
6056 };
6057
6058 // NaCl variant.  It uses different PLT contents.
6059
6060 template<int size>
6061 class Output_data_plt_x86_64_nacl : public Output_data_plt_x86_64<size>
6062 {
6063  public:
6064   Output_data_plt_x86_64_nacl(Layout* layout,
6065                               Output_data_got<64, false>* got,
6066                               Output_data_got_plt_x86_64* got_plt,
6067                               Output_data_space* got_irelative)
6068     : Output_data_plt_x86_64<size>(layout, plt_entry_size,
6069                                    got, got_plt, got_irelative)
6070   { }
6071
6072   Output_data_plt_x86_64_nacl(Layout* layout,
6073                               Output_data_got<64, false>* got,
6074                               Output_data_got_plt_x86_64* got_plt,
6075                               Output_data_space* got_irelative,
6076                               unsigned int plt_count)
6077     : Output_data_plt_x86_64<size>(layout, plt_entry_size,
6078                                    got, got_plt, got_irelative,
6079                                    plt_count)
6080   { }
6081
6082  protected:
6083   virtual unsigned int
6084   do_get_plt_entry_size() const
6085   { return plt_entry_size; }
6086
6087   virtual void
6088   do_add_eh_frame(Layout* layout)
6089   {
6090     layout->add_eh_frame_for_plt(this,
6091                                  this->plt_eh_frame_cie,
6092                                  this->plt_eh_frame_cie_size,
6093                                  plt_eh_frame_fde,
6094                                  plt_eh_frame_fde_size);
6095   }
6096
6097   virtual void
6098   do_fill_first_plt_entry(unsigned char* pov,
6099                           typename elfcpp::Elf_types<size>::Elf_Addr got_addr,
6100                           typename elfcpp::Elf_types<size>::Elf_Addr plt_addr);
6101
6102   virtual unsigned int
6103   do_fill_plt_entry(unsigned char* pov,
6104                     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
6105                     typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
6106                     unsigned int got_offset,
6107                     unsigned int plt_offset,
6108                     unsigned int plt_index);
6109
6110   virtual void
6111   do_fill_tlsdesc_entry(unsigned char* pov,
6112                         typename elfcpp::Elf_types<size>::Elf_Addr got_address,
6113                         typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
6114                         typename elfcpp::Elf_types<size>::Elf_Addr got_base,
6115                         unsigned int tlsdesc_got_offset,
6116                         unsigned int plt_offset);
6117
6118  private:
6119   // The size of an entry in the PLT.
6120   static const int plt_entry_size = 64;
6121
6122   // The first entry in the PLT.
6123   static const unsigned char first_plt_entry[plt_entry_size];
6124
6125   // Other entries in the PLT for an executable.
6126   static const unsigned char plt_entry[plt_entry_size];
6127
6128   // The reserved TLSDESC entry in the PLT for an executable.
6129   static const unsigned char tlsdesc_plt_entry[plt_entry_size];
6130
6131   // The .eh_frame unwind information for the PLT.
6132   static const int plt_eh_frame_fde_size = 32;
6133   static const unsigned char plt_eh_frame_fde[plt_eh_frame_fde_size];
6134 };
6135
6136 template<int size>
6137 class Target_x86_64_nacl : public Target_x86_64<size>
6138 {
6139  public:
6140   Target_x86_64_nacl()
6141     : Target_x86_64<size>(&x86_64_nacl_info)
6142   { }
6143
6144   virtual Output_data_plt_x86_64<size>*
6145   do_make_data_plt(Layout* layout,
6146                    Output_data_got<64, false>* got,
6147                    Output_data_got_plt_x86_64* got_plt,
6148                    Output_data_space* got_irelative)
6149   {
6150     return new Output_data_plt_x86_64_nacl<size>(layout, got, got_plt,
6151                                                  got_irelative);
6152   }
6153
6154   virtual Output_data_plt_x86_64<size>*
6155   do_make_data_plt(Layout* layout,
6156                    Output_data_got<64, false>* got,
6157                    Output_data_got_plt_x86_64* got_plt,
6158                    Output_data_space* got_irelative,
6159                    unsigned int plt_count)
6160   {
6161     return new Output_data_plt_x86_64_nacl<size>(layout, got, got_plt,
6162                                                  got_irelative,
6163                                                  plt_count);
6164   }
6165
6166   virtual std::string
6167   do_code_fill(section_size_type length) const;
6168
6169  private:
6170   static const Target::Target_info x86_64_nacl_info;
6171 };
6172
6173 template<>
6174 const Target::Target_info Target_x86_64_nacl<64>::x86_64_nacl_info =
6175 {
6176   64,                   // size
6177   false,                // is_big_endian
6178   elfcpp::EM_X86_64,    // machine_code
6179   false,                // has_make_symbol
6180   false,                // has_resolve
6181   true,                 // has_code_fill
6182   true,                 // is_default_stack_executable
6183   true,                 // can_icf_inline_merge_sections
6184   '\0',                 // wrap_char
6185   "/lib64/ld-nacl-x86-64.so.1", // dynamic_linker
6186   0x20000,              // default_text_segment_address
6187   0x10000,              // abi_pagesize (overridable by -z max-page-size)
6188   0x10000,              // common_pagesize (overridable by -z common-page-size)
6189   true,                 // isolate_execinstr
6190   0x10000000,           // rosegment_gap
6191   elfcpp::SHN_UNDEF,    // small_common_shndx
6192   elfcpp::SHN_X86_64_LCOMMON,   // large_common_shndx
6193   0,                    // small_common_section_flags
6194   elfcpp::SHF_X86_64_LARGE,     // large_common_section_flags
6195   NULL,                 // attributes_section
6196   NULL,                 // attributes_vendor
6197   "_start",             // entry_symbol_name
6198   32,                   // hash_entry_size
6199   elfcpp::SHT_X86_64_UNWIND,    // unwind_section_type
6200 };
6201
6202 template<>
6203 const Target::Target_info Target_x86_64_nacl<32>::x86_64_nacl_info =
6204 {
6205   32,                   // size
6206   false,                // is_big_endian
6207   elfcpp::EM_X86_64,    // machine_code
6208   false,                // has_make_symbol
6209   false,                // has_resolve
6210   true,                 // has_code_fill
6211   true,                 // is_default_stack_executable
6212   true,                 // can_icf_inline_merge_sections
6213   '\0',                 // wrap_char
6214   "/lib/ld-nacl-x86-64.so.1", // dynamic_linker
6215   0x20000,              // default_text_segment_address
6216   0x10000,              // abi_pagesize (overridable by -z max-page-size)
6217   0x10000,              // common_pagesize (overridable by -z common-page-size)
6218   true,                 // isolate_execinstr
6219   0x10000000,           // rosegment_gap
6220   elfcpp::SHN_UNDEF,    // small_common_shndx
6221   elfcpp::SHN_X86_64_LCOMMON,   // large_common_shndx
6222   0,                    // small_common_section_flags
6223   elfcpp::SHF_X86_64_LARGE,     // large_common_section_flags
6224   NULL,                 // attributes_section
6225   NULL,                 // attributes_vendor
6226   "_start",             // entry_symbol_name
6227   32,                   // hash_entry_size
6228   elfcpp::SHT_X86_64_UNWIND,    // unwind_section_type
6229 };
6230
6231 #define NACLMASK        0xe0            // 32-byte alignment mask.
6232
6233 // The first entry in the PLT.
6234
6235 template<int size>
6236 const unsigned char
6237 Output_data_plt_x86_64_nacl<size>::first_plt_entry[plt_entry_size] =
6238 {
6239   0xff, 0x35,                         // pushq contents of memory address
6240   0, 0, 0, 0,                         // replaced with address of .got + 8
6241   0x4c, 0x8b, 0x1d,                   // mov GOT+16(%rip), %r11
6242   0, 0, 0, 0,                         // replaced with address of .got + 16
6243   0x41, 0x83, 0xe3, NACLMASK,         // and $-32, %r11d
6244   0x4d, 0x01, 0xfb,                   // add %r15, %r11
6245   0x41, 0xff, 0xe3,                   // jmpq *%r11
6246
6247   // 9-byte nop sequence to pad out to the next 32-byte boundary.
6248   0x66, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw 0x0(%rax,%rax,1)
6249
6250   // 32 bytes of nop to pad out to the standard size
6251   0x66, 0x66, 0x66, 0x66, 0x66, 0x66,    // excess data32 prefixes
6252   0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
6253   0x66, 0x66, 0x66, 0x66, 0x66, 0x66,    // excess data32 prefixes
6254   0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
6255   0x66,                                  // excess data32 prefix
6256   0x90                                   // nop
6257 };
6258
6259 template<int size>
6260 void
6261 Output_data_plt_x86_64_nacl<size>::do_fill_first_plt_entry(
6262     unsigned char* pov,
6263     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
6264     typename elfcpp::Elf_types<size>::Elf_Addr plt_address)
6265 {
6266   memcpy(pov, first_plt_entry, plt_entry_size);
6267   elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
6268                                               (got_address + 8
6269                                                - (plt_address + 2 + 4)));
6270   elfcpp::Swap_unaligned<32, false>::writeval(pov + 9,
6271                                               (got_address + 16
6272                                                - (plt_address + 9 + 4)));
6273 }
6274
6275 // Subsequent entries in the PLT.
6276
6277 template<int size>
6278 const unsigned char
6279 Output_data_plt_x86_64_nacl<size>::plt_entry[plt_entry_size] =
6280 {
6281   0x4c, 0x8b, 0x1d,              // mov name@GOTPCREL(%rip),%r11
6282   0, 0, 0, 0,                    // replaced with address of symbol in .got
6283   0x41, 0x83, 0xe3, NACLMASK,    // and $-32, %r11d
6284   0x4d, 0x01, 0xfb,              // add %r15, %r11
6285   0x41, 0xff, 0xe3,              // jmpq *%r11
6286
6287   // 15-byte nop sequence to pad out to the next 32-byte boundary.
6288   0x66, 0x66, 0x66, 0x66, 0x66, 0x66,    // excess data32 prefixes
6289   0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
6290
6291   // Lazy GOT entries point here (32-byte aligned).
6292   0x68,                       // pushq immediate
6293   0, 0, 0, 0,                 // replaced with index into relocation table
6294   0xe9,                       // jmp relative
6295   0, 0, 0, 0,                 // replaced with offset to start of .plt0
6296
6297   // 22 bytes of nop to pad out to the standard size.
6298   0x66, 0x66, 0x66, 0x66, 0x66, 0x66,    // excess data32 prefixes
6299   0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
6300   0x0f, 0x1f, 0x80, 0, 0, 0, 0,          // nopl 0x0(%rax)
6301 };
6302
6303 template<int size>
6304 unsigned int
6305 Output_data_plt_x86_64_nacl<size>::do_fill_plt_entry(
6306     unsigned char* pov,
6307     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
6308     typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
6309     unsigned int got_offset,
6310     unsigned int plt_offset,
6311     unsigned int plt_index)
6312 {
6313   memcpy(pov, plt_entry, plt_entry_size);
6314   elfcpp::Swap_unaligned<32, false>::writeval(pov + 3,
6315                                               (got_address + got_offset
6316                                                - (plt_address + plt_offset
6317                                                   + 3 + 4)));
6318
6319   elfcpp::Swap_unaligned<32, false>::writeval(pov + 33, plt_index);
6320   elfcpp::Swap_unaligned<32, false>::writeval(pov + 38,
6321                                               - (plt_offset + 38 + 4));
6322
6323   return 32;
6324 }
6325
6326 // The reserved TLSDESC entry in the PLT.
6327
6328 template<int size>
6329 const unsigned char
6330 Output_data_plt_x86_64_nacl<size>::tlsdesc_plt_entry[plt_entry_size] =
6331 {
6332   0xff, 0x35,                   // pushq x(%rip)
6333   0, 0, 0, 0,   // replaced with address of linkmap GOT entry (at PLTGOT + 8)
6334   0x4c, 0x8b, 0x1d,             // mov y(%rip),%r11
6335   0, 0, 0, 0,   // replaced with offset of reserved TLSDESC_GOT entry
6336   0x41, 0x83, 0xe3, NACLMASK,   // and $-32, %r11d
6337   0x4d, 0x01, 0xfb,             // add %r15, %r11
6338   0x41, 0xff, 0xe3,             // jmpq *%r11
6339
6340   // 41 bytes of nop to pad out to the standard size.
6341   0x66, 0x66, 0x66, 0x66, 0x66, 0x66,    // excess data32 prefixes
6342   0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
6343   0x66, 0x66, 0x66, 0x66, 0x66, 0x66,    // excess data32 prefixes
6344   0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
6345   0x66, 0x66,                            // excess data32 prefixes
6346   0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
6347 };
6348
6349 template<int size>
6350 void
6351 Output_data_plt_x86_64_nacl<size>::do_fill_tlsdesc_entry(
6352     unsigned char* pov,
6353     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
6354     typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
6355     typename elfcpp::Elf_types<size>::Elf_Addr got_base,
6356     unsigned int tlsdesc_got_offset,
6357     unsigned int plt_offset)
6358 {
6359   memcpy(pov, tlsdesc_plt_entry, plt_entry_size);
6360   elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
6361                                               (got_address + 8
6362                                                - (plt_address + plt_offset
6363                                                   + 2 + 4)));
6364   elfcpp::Swap_unaligned<32, false>::writeval(pov + 9,
6365                                               (got_base
6366                                                + tlsdesc_got_offset
6367                                                - (plt_address + plt_offset
6368                                                   + 9 + 4)));
6369 }
6370
6371 // The .eh_frame unwind information for the PLT.
6372
6373 template<int size>
6374 const unsigned char
6375 Output_data_plt_x86_64_nacl<size>::plt_eh_frame_fde[plt_eh_frame_fde_size] =
6376 {
6377   0, 0, 0, 0,                           // Replaced with offset to .plt.
6378   0, 0, 0, 0,                           // Replaced with size of .plt.
6379   0,                                    // Augmentation size.
6380   elfcpp::DW_CFA_def_cfa_offset, 16,    // DW_CFA_def_cfa_offset: 16.
6381   elfcpp::DW_CFA_advance_loc + 6,       // Advance 6 to __PLT__ + 6.
6382   elfcpp::DW_CFA_def_cfa_offset, 24,    // DW_CFA_def_cfa_offset: 24.
6383   elfcpp::DW_CFA_advance_loc + 58,      // Advance 58 to __PLT__ + 64.
6384   elfcpp::DW_CFA_def_cfa_expression,    // DW_CFA_def_cfa_expression.
6385   13,                                   // Block length.
6386   elfcpp::DW_OP_breg7, 8,               // Push %rsp + 8.
6387   elfcpp::DW_OP_breg16, 0,              // Push %rip.
6388   elfcpp::DW_OP_const1u, 63,            // Push 0x3f.
6389   elfcpp::DW_OP_and,                    // & (%rip & 0x3f).
6390   elfcpp::DW_OP_const1u, 37,            // Push 0x25.
6391   elfcpp::DW_OP_ge,                     // >= ((%rip & 0x3f) >= 0x25)
6392   elfcpp::DW_OP_lit3,                   // Push 3.
6393   elfcpp::DW_OP_shl,                    // << (((%rip & 0x3f) >= 0x25) << 3)
6394   elfcpp::DW_OP_plus,                   // + ((((%rip&0x3f)>=0x25)<<3)+%rsp+8
6395   elfcpp::DW_CFA_nop,                   // Align to 32 bytes.
6396   elfcpp::DW_CFA_nop
6397 };
6398
6399 // Return a string used to fill a code section with nops.
6400 // For NaCl, long NOPs are only valid if they do not cross
6401 // bundle alignment boundaries, so keep it simple with one-byte NOPs.
6402 template<int size>
6403 std::string
6404 Target_x86_64_nacl<size>::do_code_fill(section_size_type length) const
6405 {
6406   return std::string(length, static_cast<char>(0x90));
6407 }
6408
6409 // The selector for x86_64-nacl object files.
6410
6411 template<int size>
6412 class Target_selector_x86_64_nacl
6413   : public Target_selector_nacl<Target_selector_x86_64<size>,
6414                                 Target_x86_64_nacl<size> >
6415 {
6416  public:
6417   Target_selector_x86_64_nacl()
6418     : Target_selector_nacl<Target_selector_x86_64<size>,
6419                            Target_x86_64_nacl<size> >("x86-64",
6420                                                       size == 64
6421                                                       ? "elf64-x86-64-nacl"
6422                                                       : "elf32-x86-64-nacl",
6423                                                       size == 64
6424                                                       ? "elf_x86_64_nacl"
6425                                                       : "elf32_x86_64_nacl")
6426   { }
6427 };
6428
6429 Target_selector_x86_64_nacl<64> target_selector_x86_64;
6430 Target_selector_x86_64_nacl<32> target_selector_x32;
6431
6432 } // End anonymous namespace.