contrib/binutils-2.27/gold/x86_64.cc

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