gold/x86_64.cc

   1 // x86_64.cc -- x86_64 target support for gold.
   2
   3 // Copyright 2006, 2007, 2008, 2009 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 "parameters.h"
  29 #include "reloc.h"
  30 #include "x86_64.h"
  31 #include "object.h"
  32 #include "symtab.h"
  33 #include "layout.h"
  34 #include "output.h"
  35 #include "copy-relocs.h"
  36 #include "target.h"
  37 #include "target-reloc.h"
  38 #include "target-select.h"
  39 #include "tls.h"
  40 #include "freebsd.h"
  41
  42 namespace
  43 {
  44
  45 using namespace gold;
  46
  47 class Output_data_plt_x86_64;
  48
  49 // The x86_64 target class.
  50 // See the ABI at
  51 //   http://www.x86-64.org/documentation/abi.pdf
  52 // TLS info comes from
  53 //   http://people.redhat.com/drepper/tls.pdf
  54 //   http://www.lsd.ic.unicamp.br/~oliva/writeups/TLS/RFC-TLSDESC-x86.txt
  55
  56 class Target_x86_64 : public Target_freebsd<64, false>
  57 {
  58  public:
  59   // In the x86_64 ABI (p 68), it says "The AMD64 ABI architectures
  60   // uses only Elf64_Rela relocation entries with explicit addends."
  61   typedef Output_data_reloc<elfcpp::SHT_RELA, true, 64, false> Reloc_section;
  62
  63   Target_x86_64()
  64     : Target_freebsd<64, false>(&x86_64_info),
  65       got_(NULL), plt_(NULL), got_plt_(NULL), rela_dyn_(NULL),
  66       copy_relocs_(elfcpp::R_X86_64_COPY), dynbss_(NULL),
  67       got_mod_index_offset_(-1U), tls_base_symbol_defined_(false)
  68   { }
  69
  70   // Scan the relocations to look for symbol adjustments.
  71   void
  72   gc_process_relocs(const General_options& options,
  73                     Symbol_table* symtab,
  74                     Layout* layout,
  75                     Sized_relobj<64, false>* object,
  76                     unsigned int data_shndx,
  77                     unsigned int sh_type,
  78                     const unsigned char* prelocs,
  79                     size_t reloc_count,
  80                     Output_section* output_section,
  81                     bool needs_special_offset_handling,
  82                     size_t local_symbol_count,
  83                     const unsigned char* plocal_symbols);
  84
  85   // Scan the relocations to look for symbol adjustments.
  86   void
  87   scan_relocs(const General_options& options,
  88               Symbol_table* symtab,
  89               Layout* layout,
  90               Sized_relobj<64, false>* object,
  91               unsigned int data_shndx,
  92               unsigned int sh_type,
  93               const unsigned char* prelocs,
  94               size_t reloc_count,
  95               Output_section* output_section,
  96               bool needs_special_offset_handling,
  97               size_t local_symbol_count,
  98               const unsigned char* plocal_symbols);
  99
 100   // Finalize the sections.
 101   void
 102   do_finalize_sections(Layout*);
 103
 104   // Return the value to use for a dynamic which requires special
 105   // treatment.
 106   uint64_t
 107   do_dynsym_value(const Symbol*) const;
 108
 109   // Relocate a section.
 110   void
 111   relocate_section(const Relocate_info<64, false>*,
 112                    unsigned int sh_type,
 113                    const unsigned char* prelocs,
 114                    size_t reloc_count,
 115                    Output_section* output_section,
 116                    bool needs_special_offset_handling,
 117                    unsigned char* view,
 118                    elfcpp::Elf_types<64>::Elf_Addr view_address,
 119                    section_size_type view_size);
 120
 121   // Scan the relocs during a relocatable link.
 122   void
 123   scan_relocatable_relocs(const General_options& options,
 124                           Symbol_table* symtab,
 125                           Layout* layout,
 126                           Sized_relobj<64, false>* object,
 127                           unsigned int data_shndx,
 128                           unsigned int sh_type,
 129                           const unsigned char* prelocs,
 130                           size_t reloc_count,
 131                           Output_section* output_section,
 132                           bool needs_special_offset_handling,
 133                           size_t local_symbol_count,
 134                           const unsigned char* plocal_symbols,
 135                           Relocatable_relocs*);
 136
 137   // Relocate a section during a relocatable link.
 138   void
 139   relocate_for_relocatable(const Relocate_info<64, false>*,
 140                            unsigned int sh_type,
 141                            const unsigned char* prelocs,
 142                            size_t reloc_count,
 143                            Output_section* output_section,
 144                            off_t offset_in_output_section,
 145                            const Relocatable_relocs*,
 146                            unsigned char* view,
 147                            elfcpp::Elf_types<64>::Elf_Addr view_address,
 148                            section_size_type view_size,
 149                            unsigned char* reloc_view,
 150                            section_size_type reloc_view_size);
 151
 152   // Return a string used to fill a code section with nops.
 153   std::string
 154   do_code_fill(section_size_type length) const;
 155
 156   // Return whether SYM is defined by the ABI.
 157   bool
 158   do_is_defined_by_abi(const Symbol* sym) const
 159   { return strcmp(sym->name(), "__tls_get_addr") == 0; }
 160
 161   // Return the size of the GOT section.
 162   section_size_type
 163   got_size()
 164   {
 165     gold_assert(this->got_ != NULL);
 166     return this->got_->data_size();
 167   }
 168
 169  private:
 170   // The class which scans relocations.
 171   class Scan
 172   {
 173   public:
 174     Scan()
 175       : issued_non_pic_error_(false)
 176     { }
 177
 178     inline void
 179     local(const General_options& options, Symbol_table* symtab,
 180           Layout* layout, Target_x86_64* target,
 181           Sized_relobj<64, false>* object,
 182           unsigned int data_shndx,
 183           Output_section* output_section,
 184           const elfcpp::Rela<64, false>& reloc, unsigned int r_type,
 185           const elfcpp::Sym<64, false>& lsym);
 186
 187     inline void
 188     global(const General_options& options, Symbol_table* symtab,
 189            Layout* layout, Target_x86_64* target,
 190            Sized_relobj<64, false>* object,
 191            unsigned int data_shndx,
 192            Output_section* output_section,
 193            const elfcpp::Rela<64, false>& reloc, unsigned int r_type,
 194            Symbol* gsym);
 195
 196   private:
 197     static void
 198     unsupported_reloc_local(Sized_relobj<64, false>*, unsigned int r_type);
 199
 200     static void
 201     unsupported_reloc_global(Sized_relobj<64, false>*, unsigned int r_type,
 202                              Symbol*);
 203
 204     void
 205     check_non_pic(Relobj*, unsigned int r_type);
 206
 207     // Whether we have issued an error about a non-PIC compilation.
 208     bool issued_non_pic_error_;
 209   };
 210
 211   // The class which implements relocation.
 212   class Relocate
 213   {
 214    public:
 215     Relocate()
 216       : skip_call_tls_get_addr_(false), saw_tls_block_reloc_(false)
 217     { }
 218
 219     ~Relocate()
 220     {
 221       if (this->skip_call_tls_get_addr_)
 222         {
 223           // FIXME: This needs to specify the location somehow.
 224           gold_error(_("missing expected TLS relocation"));
 225         }
 226     }
 227
 228     // Do a relocation.  Return false if the caller should not issue
 229     // any warnings about this relocation.
 230     inline bool
 231     relocate(const Relocate_info<64, false>*, Target_x86_64*, Output_section*,
 232              size_t relnum, const elfcpp::Rela<64, false>&,
 233              unsigned int r_type, const Sized_symbol<64>*,
 234              const Symbol_value<64>*,
 235              unsigned char*, elfcpp::Elf_types<64>::Elf_Addr,
 236              section_size_type);
 237
 238    private:
 239     // Do a TLS relocation.
 240     inline void
 241     relocate_tls(const Relocate_info<64, false>*, Target_x86_64*,
 242                  size_t relnum, const elfcpp::Rela<64, false>&,
 243                  unsigned int r_type, const Sized_symbol<64>*,
 244                  const Symbol_value<64>*,
 245                  unsigned char*, elfcpp::Elf_types<64>::Elf_Addr,
 246                  section_size_type);
 247
 248     // Do a TLS General-Dynamic to Initial-Exec transition.
 249     inline void
 250     tls_gd_to_ie(const Relocate_info<64, false>*, size_t relnum,
 251                  Output_segment* tls_segment,
 252                  const elfcpp::Rela<64, false>&, unsigned int r_type,
 253                  elfcpp::Elf_types<64>::Elf_Addr value,
 254                  unsigned char* view,
 255                  elfcpp::Elf_types<64>::Elf_Addr,
 256                  section_size_type view_size);
 257
 258     // Do a TLS General-Dynamic to Local-Exec transition.
 259     inline void
 260     tls_gd_to_le(const Relocate_info<64, false>*, size_t relnum,
 261                  Output_segment* tls_segment,
 262                  const elfcpp::Rela<64, false>&, unsigned int r_type,
 263                  elfcpp::Elf_types<64>::Elf_Addr value,
 264                  unsigned char* view,
 265                  section_size_type view_size);
 266
 267     // Do a TLSDESC-style General-Dynamic to Initial-Exec transition.
 268     inline void
 269     tls_desc_gd_to_ie(const Relocate_info<64, false>*, size_t relnum,
 270                       Output_segment* tls_segment,
 271                       const elfcpp::Rela<64, false>&, unsigned int r_type,
 272                       elfcpp::Elf_types<64>::Elf_Addr value,
 273                       unsigned char* view,
 274                       elfcpp::Elf_types<64>::Elf_Addr,
 275                       section_size_type view_size);
 276
 277     // Do a TLSDESC-style General-Dynamic to Local-Exec transition.
 278     inline void
 279     tls_desc_gd_to_le(const Relocate_info<64, false>*, size_t relnum,
 280                       Output_segment* tls_segment,
 281                       const elfcpp::Rela<64, false>&, unsigned int r_type,
 282                       elfcpp::Elf_types<64>::Elf_Addr value,
 283                       unsigned char* view,
 284                       section_size_type view_size);
 285
 286     // Do a TLS Local-Dynamic to Local-Exec transition.
 287     inline void
 288     tls_ld_to_le(const Relocate_info<64, false>*, size_t relnum,
 289                  Output_segment* tls_segment,
 290                  const elfcpp::Rela<64, false>&, unsigned int r_type,
 291                  elfcpp::Elf_types<64>::Elf_Addr value,
 292                  unsigned char* view,
 293                  section_size_type view_size);
 294
 295     // Do a TLS Initial-Exec to Local-Exec transition.
 296     static inline void
 297     tls_ie_to_le(const Relocate_info<64, false>*, size_t relnum,
 298                  Output_segment* tls_segment,
 299                  const elfcpp::Rela<64, false>&, unsigned int r_type,
 300                  elfcpp::Elf_types<64>::Elf_Addr value,
 301                  unsigned char* view,
 302                  section_size_type view_size);
 303
 304     // This is set if we should skip the next reloc, which should be a
 305     // PLT32 reloc against ___tls_get_addr.
 306     bool skip_call_tls_get_addr_;
 307
 308     // This is set if we see a relocation which could load the address
 309     // of the TLS block.  Whether we see such a relocation determines
 310     // how we handle the R_X86_64_DTPOFF32 relocation, which is used
 311     // in debugging sections.
 312     bool saw_tls_block_reloc_;
 313   };
 314
 315   // A class which returns the size required for a relocation type,
 316   // used while scanning relocs during a relocatable link.
 317   class Relocatable_size_for_reloc
 318   {
 319    public:
 320     unsigned int
 321     get_size_for_reloc(unsigned int, Relobj*);
 322   };
 323
 324   // Adjust TLS relocation type based on the options and whether this
 325   // is a local symbol.
 326   static tls::Tls_optimization
 327   optimize_tls_reloc(bool is_final, int r_type);
 328
 329   // Get the GOT section, creating it if necessary.
 330   Output_data_got<64, false>*
 331   got_section(Symbol_table*, Layout*);
 332
 333   // Get the GOT PLT section.
 334   Output_data_space*
 335   got_plt_section() const
 336   {
 337     gold_assert(this->got_plt_ != NULL);
 338     return this->got_plt_;
 339   }
 340
 341   // Create the PLT section.
 342   void
 343   make_plt_section(Symbol_table* symtab, Layout* layout);
 344
 345   // Create a PLT entry for a global symbol.
 346   void
 347   make_plt_entry(Symbol_table*, Layout*, Symbol*);
 348
 349   // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
 350   void
 351   define_tls_base_symbol(Symbol_table*, Layout*);
 352
 353   // Create the reserved PLT and GOT entries for the TLS descriptor resolver.
 354   void
 355   reserve_tlsdesc_entries(Symbol_table* symtab, Layout* layout);
 356
 357   // Create a GOT entry for the TLS module index.
 358   unsigned int
 359   got_mod_index_entry(Symbol_table* symtab, Layout* layout,
 360                       Sized_relobj<64, false>* object);
 361
 362   // Get the PLT section.
 363   Output_data_plt_x86_64*
 364   plt_section() const
 365   {
 366     gold_assert(this->plt_ != NULL);
 367     return this->plt_;
 368   }
 369
 370   // Get the dynamic reloc section, creating it if necessary.
 371   Reloc_section*
 372   rela_dyn_section(Layout*);
 373
 374   // Return true if the symbol may need a COPY relocation.
 375   // References from an executable object to non-function symbols
 376   // defined in a dynamic object may need a COPY relocation.
 377   bool
 378   may_need_copy_reloc(Symbol* gsym)
 379   {
 380     return (!parameters->options().shared()
 381             && gsym->is_from_dynobj()
 382             && gsym->type() != elfcpp::STT_FUNC);
 383   }
 384
 385   // Add a potential copy relocation.
 386   void
 387   copy_reloc(Symbol_table* symtab, Layout* layout,
 388              Sized_relobj<64, false>* object,
 389              unsigned int shndx, Output_section* output_section,
 390              Symbol* sym, const elfcpp::Rela<64, false>& reloc)
 391   {
 392     this->copy_relocs_.copy_reloc(symtab, layout,
 393                                   symtab->get_sized_symbol<64>(sym),
 394                                   object, shndx, output_section,
 395                                   reloc, this->rela_dyn_section(layout));
 396   }
 397
 398   // Information about this specific target which we pass to the
 399   // general Target structure.
 400   static const Target::Target_info x86_64_info;
 401
 402   enum Got_type
 403   {
 404     GOT_TYPE_STANDARD = 0,      // GOT entry for a regular symbol
 405     GOT_TYPE_TLS_OFFSET = 1,    // GOT entry for TLS offset
 406     GOT_TYPE_TLS_PAIR = 2,      // GOT entry for TLS module/offset pair
 407     GOT_TYPE_TLS_DESC = 3       // GOT entry for TLS_DESC pair
 408   };
 409
 410   // The GOT section.
 411   Output_data_got<64, false>* got_;
 412   // The PLT section.
 413   Output_data_plt_x86_64* plt_;
 414   // The GOT PLT section.
 415   Output_data_space* got_plt_;
 416   // The dynamic reloc section.
 417   Reloc_section* rela_dyn_;
 418   // Relocs saved to avoid a COPY reloc.
 419   Copy_relocs<elfcpp::SHT_RELA, 64, false> copy_relocs_;
 420   // Space for variables copied with a COPY reloc.
 421   Output_data_space* dynbss_;
 422   // Offset of the GOT entry for the TLS module index.
 423   unsigned int got_mod_index_offset_;
 424   // True if the _TLS_MODULE_BASE_ symbol has been defined.
 425   bool tls_base_symbol_defined_;
 426 };
 427
 428 const Target::Target_info Target_x86_64::x86_64_info =
 429 {
 430   64,                   // size
 431   false,                // is_big_endian
 432   elfcpp::EM_X86_64,    // machine_code
 433   false,                // has_make_symbol
 434   false,                // has_resolve
 435   true,                 // has_code_fill
 436   true,                 // is_default_stack_executable
 437   '\0',                 // wrap_char
 438   "/lib/ld64.so.1",     // program interpreter
 439   0x400000,             // default_text_segment_address
 440   0x1000,               // abi_pagesize (overridable by -z max-page-size)
 441   0x1000                // common_pagesize (overridable by -z common-page-size)
 442 };
 443
 444 // Get the GOT section, creating it if necessary.
 445
 446 Output_data_got<64, false>*
 447 Target_x86_64::got_section(Symbol_table* symtab, Layout* layout)
 448 {
 449   if (this->got_ == NULL)
 450     {
 451       gold_assert(symtab != NULL && layout != NULL);
 452
 453       this->got_ = new Output_data_got<64, false>();
 454
 455       Output_section* os;
 456       os = layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
 457                                            (elfcpp::SHF_ALLOC
 458                                             | elfcpp::SHF_WRITE),
 459                                            this->got_);
 460       os->set_is_relro();
 461
 462       // The old GNU linker creates a .got.plt section.  We just
 463       // create another set of data in the .got section.  Note that we
 464       // always create a PLT if we create a GOT, although the PLT
 465       // might be empty.
 466       this->got_plt_ = new Output_data_space(8, "** GOT PLT");
 467       os = layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
 468                                            (elfcpp::SHF_ALLOC
 469                                             | elfcpp::SHF_WRITE),
 470                                            this->got_plt_);
 471       os->set_is_relro();
 472
 473       // The first three entries are reserved.
 474       this->got_plt_->set_current_data_size(3 * 8);
 475
 476       // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
 477       symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
 478                                     this->got_plt_,
 479                                     0, 0, elfcpp::STT_OBJECT,
 480                                     elfcpp::STB_LOCAL,
 481                                     elfcpp::STV_HIDDEN, 0,
 482                                     false, false);
 483     }
 484
 485   return this->got_;
 486 }
 487
 488 // Get the dynamic reloc section, creating it if necessary.
 489
 490 Target_x86_64::Reloc_section*
 491 Target_x86_64::rela_dyn_section(Layout* layout)
 492 {
 493   if (this->rela_dyn_ == NULL)
 494     {
 495       gold_assert(layout != NULL);
 496       this->rela_dyn_ = new Reloc_section(parameters->options().combreloc());
 497       layout->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA,
 498                                       elfcpp::SHF_ALLOC, this->rela_dyn_);
 499     }
 500   return this->rela_dyn_;
 501 }
 502
 503 // A class to handle the PLT data.
 504
 505 class Output_data_plt_x86_64 : public Output_section_data
 506 {
 507  public:
 508   typedef Output_data_reloc<elfcpp::SHT_RELA, true, 64, false> Reloc_section;
 509
 510   Output_data_plt_x86_64(Layout*, Output_data_got<64, false>*,
 511                          Output_data_space*);
 512
 513   // Add an entry to the PLT.
 514   void
 515   add_entry(Symbol* gsym);
 516
 517   // Add the reserved TLSDESC_PLT entry to the PLT.
 518   void
 519   reserve_tlsdesc_entry(unsigned int got_offset)
 520   { this->tlsdesc_got_offset_ = got_offset; }
 521
 522   // Return true if a TLSDESC_PLT entry has been reserved.
 523   bool
 524   has_tlsdesc_entry() const
 525   { return this->tlsdesc_got_offset_ != -1U; }
 526
 527   // Return the GOT offset for the reserved TLSDESC_PLT entry.
 528   unsigned int
 529   get_tlsdesc_got_offset() const
 530   { return this->tlsdesc_got_offset_; }
 531
 532   // Return the offset of the reserved TLSDESC_PLT entry.
 533   unsigned int
 534   get_tlsdesc_plt_offset() const
 535   { return (this->count_ + 1) * plt_entry_size; }
 536
 537   // Return the .rel.plt section data.
 538   const Reloc_section*
 539   rel_plt() const
 540   { return this->rel_; }
 541
 542  protected:
 543   void
 544   do_adjust_output_section(Output_section* os);
 545
 546   // Write to a map file.
 547   void
 548   do_print_to_mapfile(Mapfile* mapfile) const
 549   { mapfile->print_output_data(this, _("** PLT")); }
 550
 551  private:
 552   // The size of an entry in the PLT.
 553   static const int plt_entry_size = 16;
 554
 555   // The first entry in the PLT.
 556   // From the AMD64 ABI: "Unlike Intel386 ABI, this ABI uses the same
 557   // procedure linkage table for both programs and shared objects."
 558   static unsigned char first_plt_entry[plt_entry_size];
 559
 560   // Other entries in the PLT for an executable.
 561   static unsigned char plt_entry[plt_entry_size];
 562
 563   // The reserved TLSDESC entry in the PLT for an executable.
 564   static unsigned char tlsdesc_plt_entry[plt_entry_size];
 565
 566   // Set the final size.
 567   void
 568   set_final_data_size();
 569
 570   // Write out the PLT data.
 571   void
 572   do_write(Output_file*);
 573
 574   // The reloc section.
 575   Reloc_section* rel_;
 576   // The .got section.
 577   Output_data_got<64, false>* got_;
 578   // The .got.plt section.
 579   Output_data_space* got_plt_;
 580   // The number of PLT entries.
 581   unsigned int count_;
 582   // Offset of the reserved TLSDESC_GOT entry when needed.
 583   unsigned int tlsdesc_got_offset_;
 584 };
 585
 586 // Create the PLT section.  The ordinary .got section is an argument,
 587 // since we need to refer to the start.  We also create our own .got
 588 // section just for PLT entries.
 589
 590 Output_data_plt_x86_64::Output_data_plt_x86_64(Layout* layout,
 591                                                Output_data_got<64, false>* got,
 592                                                Output_data_space* got_plt)
 593   : Output_section_data(8), got_(got), got_plt_(got_plt), count_(0),
 594     tlsdesc_got_offset_(-1U)
 595 {
 596   this->rel_ = new Reloc_section(false);
 597   layout->add_output_section_data(".rela.plt", elfcpp::SHT_RELA,
 598                                   elfcpp::SHF_ALLOC, this->rel_);
 599 }
 600
 601 void
 602 Output_data_plt_x86_64::do_adjust_output_section(Output_section* os)
 603 {
 604   // UnixWare sets the entsize of .plt to 4, and so does the old GNU
 605   // linker, and so do we.
 606   os->set_entsize(4);
 607 }
 608
 609 // Add an entry to the PLT.
 610
 611 void
 612 Output_data_plt_x86_64::add_entry(Symbol* gsym)
 613 {
 614   gold_assert(!gsym->has_plt_offset());
 615
 616   // Note that when setting the PLT offset we skip the initial
 617   // reserved PLT entry.
 618   gsym->set_plt_offset((this->count_ + 1) * plt_entry_size);
 619
 620   ++this->count_;
 621
 622   section_offset_type got_offset = this->got_plt_->current_data_size();
 623
 624   // Every PLT entry needs a GOT entry which points back to the PLT
 625   // entry (this will be changed by the dynamic linker, normally
 626   // lazily when the function is called).
 627   this->got_plt_->set_current_data_size(got_offset + 8);
 628
 629   // Every PLT entry needs a reloc.
 630   gsym->set_needs_dynsym_entry();
 631   this->rel_->add_global(gsym, elfcpp::R_X86_64_JUMP_SLOT, this->got_plt_,
 632                          got_offset, 0);
 633
 634   // Note that we don't need to save the symbol.  The contents of the
 635   // PLT are independent of which symbols are used.  The symbols only
 636   // appear in the relocations.
 637 }
 638
 639 // Set the final size.
 640 void
 641 Output_data_plt_x86_64::set_final_data_size()
 642 {
 643   unsigned int count = this->count_;
 644   if (this->has_tlsdesc_entry())
 645     ++count;
 646   this->set_data_size((count + 1) * plt_entry_size);
 647 }
 648
 649 // The first entry in the PLT for an executable.
 650
 651 unsigned char Output_data_plt_x86_64::first_plt_entry[plt_entry_size] =
 652 {
 653   // From AMD64 ABI Draft 0.98, page 76
 654   0xff, 0x35,   // pushq contents of memory address
 655   0, 0, 0, 0,   // replaced with address of .got + 8
 656   0xff, 0x25,   // jmp indirect
 657   0, 0, 0, 0,   // replaced with address of .got + 16
 658   0x90, 0x90, 0x90, 0x90   // noop (x4)
 659 };
 660
 661 // Subsequent entries in the PLT for an executable.
 662
 663 unsigned char Output_data_plt_x86_64::plt_entry[plt_entry_size] =
 664 {
 665   // From AMD64 ABI Draft 0.98, page 76
 666   0xff, 0x25,   // jmpq indirect
 667   0, 0, 0, 0,   // replaced with address of symbol in .got
 668   0x68,         // pushq immediate
 669   0, 0, 0, 0,   // replaced with offset into relocation table
 670   0xe9,         // jmpq relative
 671   0, 0, 0, 0    // replaced with offset to start of .plt
 672 };
 673
 674 // The reserved TLSDESC entry in the PLT for an executable.
 675
 676 unsigned char Output_data_plt_x86_64::tlsdesc_plt_entry[plt_entry_size] =
 677 {
 678   // From Alexandre Oliva, "Thread-Local Storage Descriptors for IA32
 679   // and AMD64/EM64T", Version 0.9.4 (2005-10-10).
 680   0xff, 0x35,   // pushq x(%rip)
 681   0, 0, 0, 0,   // replaced with address of linkmap GOT entry (at PLTGOT + 8)
 682   0xff, 0x25,   // jmpq *y(%rip)
 683   0, 0, 0, 0,   // replaced with offset of reserved TLSDESC_GOT entry
 684   0x0f, 0x1f,   // nop
 685   0x40, 0
 686 };
 687
 688 // Write out the PLT.  This uses the hand-coded instructions above,
 689 // and adjusts them as needed.  This is specified by the AMD64 ABI.
 690
 691 void
 692 Output_data_plt_x86_64::do_write(Output_file* of)
 693 {
 694   const off_t offset = this->offset();
 695   const section_size_type oview_size =
 696     convert_to_section_size_type(this->data_size());
 697   unsigned char* const oview = of->get_output_view(offset, oview_size);
 698
 699   const off_t got_file_offset = this->got_plt_->offset();
 700   const section_size_type got_size =
 701     convert_to_section_size_type(this->got_plt_->data_size());
 702   unsigned char* const got_view = of->get_output_view(got_file_offset,
 703                                                       got_size);
 704
 705   unsigned char* pov = oview;
 706
 707   // The base address of the .plt section.
 708   elfcpp::Elf_types<64>::Elf_Addr plt_address = this->address();
 709   // The base address of the .got section.
 710   elfcpp::Elf_types<64>::Elf_Addr got_base = this->got_->address();
 711   // The base address of the PLT portion of the .got section,
 712   // which is where the GOT pointer will point, and where the
 713   // three reserved GOT entries are located.
 714   elfcpp::Elf_types<64>::Elf_Addr got_address = this->got_plt_->address();
 715
 716   memcpy(pov, first_plt_entry, plt_entry_size);
 717   // We do a jmp relative to the PC at the end of this instruction.
 718   elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
 719                                               (got_address + 8
 720                                                - (plt_address + 6)));
 721   elfcpp::Swap<32, false>::writeval(pov + 8,
 722                                     (got_address + 16
 723                                      - (plt_address + 12)));
 724   pov += plt_entry_size;
 725
 726   unsigned char* got_pov = got_view;
 727
 728   memset(got_pov, 0, 24);
 729   got_pov += 24;
 730
 731   unsigned int plt_offset = plt_entry_size;
 732   unsigned int got_offset = 24;
 733   const unsigned int count = this->count_;
 734   for (unsigned int plt_index = 0;
 735        plt_index < count;
 736        ++plt_index,
 737          pov += plt_entry_size,
 738          got_pov += 8,
 739          plt_offset += plt_entry_size,
 740          got_offset += 8)
 741     {
 742       // Set and adjust the PLT entry itself.
 743       memcpy(pov, plt_entry, plt_entry_size);
 744       elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
 745                                                   (got_address + got_offset
 746                                                    - (plt_address + plt_offset
 747                                                       + 6)));
 748
 749       elfcpp::Swap_unaligned<32, false>::writeval(pov + 7, plt_index);
 750       elfcpp::Swap<32, false>::writeval(pov + 12,
 751                                         - (plt_offset + plt_entry_size));
 752
 753       // Set the entry in the GOT.
 754       elfcpp::Swap<64, false>::writeval(got_pov, plt_address + plt_offset + 6);
 755     }
 756
 757   if (this->has_tlsdesc_entry())
 758     {
 759       // Set and adjust the reserved TLSDESC PLT entry.
 760       unsigned int tlsdesc_got_offset = this->get_tlsdesc_got_offset();
 761       memcpy(pov, tlsdesc_plt_entry, plt_entry_size);
 762       elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
 763                                                   (got_address + 8
 764                                                    - (plt_address + plt_offset
 765                                                       + 6)));
 766       elfcpp::Swap_unaligned<32, false>::writeval(pov + 8,
 767                                                   (got_base
 768                                                    + tlsdesc_got_offset
 769                                                    - (plt_address + plt_offset
 770                                                       + 12)));
 771       pov += plt_entry_size;
 772     }
 773
 774   gold_assert(static_cast<section_size_type>(pov - oview) == oview_size);
 775   gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size);
 776
 777   of->write_output_view(offset, oview_size, oview);
 778   of->write_output_view(got_file_offset, got_size, got_view);
 779 }
 780
 781 // Create the PLT section.
 782
 783 void
 784 Target_x86_64::make_plt_section(Symbol_table* symtab, Layout* layout)
 785 {
 786   if (this->plt_ == NULL)
 787     {
 788       // Create the GOT sections first.
 789       this->got_section(symtab, layout);
 790
 791       this->plt_ = new Output_data_plt_x86_64(layout, this->got_,
 792                                               this->got_plt_);
 793       layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
 794                                       (elfcpp::SHF_ALLOC
 795                                        | elfcpp::SHF_EXECINSTR),
 796                                       this->plt_);
 797     }
 798 }
 799
 800 // Create a PLT entry for a global symbol.
 801
 802 void
 803 Target_x86_64::make_plt_entry(Symbol_table* symtab, Layout* layout,
 804                               Symbol* gsym)
 805 {
 806   if (gsym->has_plt_offset())
 807     return;
 808
 809   if (this->plt_ == NULL)
 810     this->make_plt_section(symtab, layout);
 811
 812   this->plt_->add_entry(gsym);
 813 }
 814
 815 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
 816
 817 void
 818 Target_x86_64::define_tls_base_symbol(Symbol_table* symtab, Layout* layout)
 819 {
 820   if (this->tls_base_symbol_defined_)
 821     return;
 822
 823   Output_segment* tls_segment = layout->tls_segment();
 824   if (tls_segment != NULL)
 825     {
 826       bool is_exec = parameters->options().output_is_executable();
 827       symtab->define_in_output_segment("_TLS_MODULE_BASE_", NULL,
 828                                        tls_segment, 0, 0,
 829                                        elfcpp::STT_TLS,
 830                                        elfcpp::STB_LOCAL,
 831                                        elfcpp::STV_HIDDEN, 0,
 832                                        (is_exec
 833                                         ? Symbol::SEGMENT_END
 834                                         : Symbol::SEGMENT_START),
 835                                        true);
 836     }
 837   this->tls_base_symbol_defined_ = true;
 838 }
 839
 840 // Create the reserved PLT and GOT entries for the TLS descriptor resolver.
 841
 842 void
 843 Target_x86_64::reserve_tlsdesc_entries(Symbol_table* symtab,
 844                                              Layout* layout)
 845 {
 846   if (this->plt_ == NULL)
 847     this->make_plt_section(symtab, layout);
 848
 849   if (!this->plt_->has_tlsdesc_entry())
 850     {
 851       // Allocate the TLSDESC_GOT entry.
 852       Output_data_got<64, false>* got = this->got_section(symtab, layout);
 853       unsigned int got_offset = got->add_constant(0);
 854
 855       // Allocate the TLSDESC_PLT entry.
 856       this->plt_->reserve_tlsdesc_entry(got_offset);
 857     }
 858 }
 859
 860 // Create a GOT entry for the TLS module index.
 861
 862 unsigned int
 863 Target_x86_64::got_mod_index_entry(Symbol_table* symtab, Layout* layout,
 864                                    Sized_relobj<64, false>* object)
 865 {
 866   if (this->got_mod_index_offset_ == -1U)
 867     {
 868       gold_assert(symtab != NULL && layout != NULL && object != NULL);
 869       Reloc_section* rela_dyn = this->rela_dyn_section(layout);
 870       Output_data_got<64, false>* got = this->got_section(symtab, layout);
 871       unsigned int got_offset = got->add_constant(0);
 872       rela_dyn->add_local(object, 0, elfcpp::R_X86_64_DTPMOD64, got,
 873                           got_offset, 0);
 874       got->add_constant(0);
 875       this->got_mod_index_offset_ = got_offset;
 876     }
 877   return this->got_mod_index_offset_;
 878 }
 879
 880 // Optimize the TLS relocation type based on what we know about the
 881 // symbol.  IS_FINAL is true if the final address of this symbol is
 882 // known at link time.
 883
 884 tls::Tls_optimization
 885 Target_x86_64::optimize_tls_reloc(bool is_final, int r_type)
 886 {
 887   // If we are generating a shared library, then we can't do anything
 888   // in the linker.
 889   if (parameters->options().shared())
 890     return tls::TLSOPT_NONE;
 891
 892   switch (r_type)
 893     {
 894     case elfcpp::R_X86_64_TLSGD:
 895     case elfcpp::R_X86_64_GOTPC32_TLSDESC:
 896     case elfcpp::R_X86_64_TLSDESC_CALL:
 897       // These are General-Dynamic which permits fully general TLS
 898       // access.  Since we know that we are generating an executable,
 899       // we can convert this to Initial-Exec.  If we also know that
 900       // this is a local symbol, we can further switch to Local-Exec.
 901       if (is_final)
 902         return tls::TLSOPT_TO_LE;
 903       return tls::TLSOPT_TO_IE;
 904
 905     case elfcpp::R_X86_64_TLSLD:
 906       // This is Local-Dynamic, which refers to a local symbol in the
 907       // dynamic TLS block.  Since we know that we generating an
 908       // executable, we can switch to Local-Exec.
 909       return tls::TLSOPT_TO_LE;
 910
 911     case elfcpp::R_X86_64_DTPOFF32:
 912     case elfcpp::R_X86_64_DTPOFF64:
 913       // Another Local-Dynamic reloc.
 914       return tls::TLSOPT_TO_LE;
 915
 916     case elfcpp::R_X86_64_GOTTPOFF:
 917       // These are Initial-Exec relocs which get the thread offset
 918       // from the GOT.  If we know that we are linking against the
 919       // local symbol, we can switch to Local-Exec, which links the
 920       // thread offset into the instruction.
 921       if (is_final)
 922         return tls::TLSOPT_TO_LE;
 923       return tls::TLSOPT_NONE;
 924
 925     case elfcpp::R_X86_64_TPOFF32:
 926       // When we already have Local-Exec, there is nothing further we
 927       // can do.
 928       return tls::TLSOPT_NONE;
 929
 930     default:
 931       gold_unreachable();
 932     }
 933 }
 934
 935 // Report an unsupported relocation against a local symbol.
 936
 937 void
 938 Target_x86_64::Scan::unsupported_reloc_local(Sized_relobj<64, false>* object,
 939                                              unsigned int r_type)
 940 {
 941   gold_error(_("%s: unsupported reloc %u against local symbol"),
 942              object->name().c_str(), r_type);
 943 }
 944
 945 // We are about to emit a dynamic relocation of type R_TYPE.  If the
 946 // dynamic linker does not support it, issue an error.  The GNU linker
 947 // only issues a non-PIC error for an allocated read-only section.
 948 // Here we know the section is allocated, but we don't know that it is
 949 // read-only.  But we check for all the relocation types which the
 950 // glibc dynamic linker supports, so it seems appropriate to issue an
 951 // error even if the section is not read-only.
 952
 953 void
 954 Target_x86_64::Scan::check_non_pic(Relobj* object, unsigned int r_type)
 955 {
 956   switch (r_type)
 957     {
 958       // These are the relocation types supported by glibc for x86_64.
 959     case elfcpp::R_X86_64_RELATIVE:
 960     case elfcpp::R_X86_64_GLOB_DAT:
 961     case elfcpp::R_X86_64_JUMP_SLOT:
 962     case elfcpp::R_X86_64_DTPMOD64:
 963     case elfcpp::R_X86_64_DTPOFF64:
 964     case elfcpp::R_X86_64_TPOFF64:
 965     case elfcpp::R_X86_64_64:
 966     case elfcpp::R_X86_64_32:
 967     case elfcpp::R_X86_64_PC32:
 968     case elfcpp::R_X86_64_COPY:
 969       return;
 970
 971     default:
 972       // This prevents us from issuing more than one error per reloc
 973       // section.  But we can still wind up issuing more than one
 974       // error per object file.
 975       if (this->issued_non_pic_error_)
 976         return;
 977       gold_assert(parameters->options().output_is_position_independent());
 978       object->error(_("requires unsupported dynamic reloc; "
 979                       "recompile with -fPIC"));
 980       this->issued_non_pic_error_ = true;
 981       return;
 982
 983     case elfcpp::R_X86_64_NONE:
 984       gold_unreachable();
 985     }
 986 }
 987
 988 // Scan a relocation for a local symbol.
 989
 990 inline void
 991 Target_x86_64::Scan::local(const General_options&,
 992                            Symbol_table* symtab,
 993                            Layout* layout,
 994                            Target_x86_64* target,
 995                            Sized_relobj<64, false>* object,
 996                            unsigned int data_shndx,
 997                            Output_section* output_section,
 998                            const elfcpp::Rela<64, false>& reloc,
 999                            unsigned int r_type,
1000                            const elfcpp::Sym<64, false>& lsym)
1001 {
1002   switch (r_type)
1003     {
1004     case elfcpp::R_X86_64_NONE:
1005     case elfcpp::R_386_GNU_VTINHERIT:
1006     case elfcpp::R_386_GNU_VTENTRY:
1007       break;
1008
1009     case elfcpp::R_X86_64_64:
1010       // If building a shared library (or a position-independent
1011       // executable), we need to create a dynamic relocation for this
1012       // location.  The relocation applied at link time will apply the
1013       // link-time value, so we flag the location with an
1014       // R_X86_64_RELATIVE relocation so the dynamic loader can
1015       // relocate it easily.
1016       if (parameters->options().output_is_position_independent())
1017         {
1018           unsigned int r_sym = elfcpp::elf_r_sym<64>(reloc.get_r_info());
1019           Reloc_section* rela_dyn = target->rela_dyn_section(layout);
1020           rela_dyn->add_local_relative(object, r_sym,
1021                                        elfcpp::R_X86_64_RELATIVE,
1022                                        output_section, data_shndx,
1023                                        reloc.get_r_offset(),
1024                                        reloc.get_r_addend());
1025         }
1026       break;
1027
1028     case elfcpp::R_X86_64_32:
1029     case elfcpp::R_X86_64_32S:
1030     case elfcpp::R_X86_64_16:
1031     case elfcpp::R_X86_64_8:
1032       // If building a shared library (or a position-independent
1033       // executable), we need to create a dynamic relocation for this
1034       // location.  We can't use an R_X86_64_RELATIVE relocation
1035       // because that is always a 64-bit relocation.
1036       if (parameters->options().output_is_position_independent())
1037         {
1038           this->check_non_pic(object, r_type);
1039
1040           Reloc_section* rela_dyn = target->rela_dyn_section(layout);
1041           unsigned int r_sym = elfcpp::elf_r_sym<64>(reloc.get_r_info());
1042           if (lsym.get_st_type() != elfcpp::STT_SECTION)
1043             rela_dyn->add_local(object, r_sym, r_type, output_section,
1044                                 data_shndx, reloc.get_r_offset(),
1045                                 reloc.get_r_addend());
1046           else
1047             {
1048               gold_assert(lsym.get_st_value() == 0);
1049               unsigned int shndx = lsym.get_st_shndx();
1050               bool is_ordinary;
1051               shndx = object->adjust_sym_shndx(r_sym, shndx,
1052                                                &is_ordinary);
1053               if (!is_ordinary)
1054                 object->error(_("section symbol %u has bad shndx %u"),
1055                               r_sym, shndx);
1056               else
1057                 rela_dyn->add_local_section(object, shndx,
1058                                             r_type, output_section,
1059                                             data_shndx, reloc.get_r_offset(),
1060                                             reloc.get_r_addend());
1061             }
1062         }
1063       break;
1064
1065     case elfcpp::R_X86_64_PC64:
1066     case elfcpp::R_X86_64_PC32:
1067     case elfcpp::R_X86_64_PC16:
1068     case elfcpp::R_X86_64_PC8:
1069       break;
1070
1071     case elfcpp::R_X86_64_PLT32:
1072       // Since we know this is a local symbol, we can handle this as a
1073       // PC32 reloc.
1074       break;
1075
1076     case elfcpp::R_X86_64_GOTPC32:
1077     case elfcpp::R_X86_64_GOTOFF64:
1078     case elfcpp::R_X86_64_GOTPC64:
1079     case elfcpp::R_X86_64_PLTOFF64:
1080       // We need a GOT section.
1081       target->got_section(symtab, layout);
1082       // For PLTOFF64, we'd normally want a PLT section, but since we
1083       // know this is a local symbol, no PLT is needed.
1084       break;
1085
1086     case elfcpp::R_X86_64_GOT64:
1087     case elfcpp::R_X86_64_GOT32:
1088     case elfcpp::R_X86_64_GOTPCREL64:
1089     case elfcpp::R_X86_64_GOTPCREL:
1090     case elfcpp::R_X86_64_GOTPLT64:
1091       {
1092         // The symbol requires a GOT entry.
1093         Output_data_got<64, false>* got = target->got_section(symtab, layout);
1094         unsigned int r_sym = elfcpp::elf_r_sym<64>(reloc.get_r_info());
1095         if (got->add_local(object, r_sym, GOT_TYPE_STANDARD))
1096           {
1097             // If we are generating a shared object, we need to add a
1098             // dynamic relocation for this symbol's GOT entry.
1099             if (parameters->options().output_is_position_independent())
1100               {
1101                 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
1102                 // R_X86_64_RELATIVE assumes a 64-bit relocation.
1103                 if (r_type != elfcpp::R_X86_64_GOT32)
1104                   rela_dyn->add_local_relative(
1105                       object, r_sym, elfcpp::R_X86_64_RELATIVE, got,
1106                       object->local_got_offset(r_sym, GOT_TYPE_STANDARD), 0);
1107                 else
1108                   {
1109                     this->check_non_pic(object, r_type);
1110
1111                     gold_assert(lsym.get_st_type() != elfcpp::STT_SECTION);
1112                     rela_dyn->add_local(
1113                         object, r_sym, r_type, got,
1114                         object->local_got_offset(r_sym, GOT_TYPE_STANDARD), 0);
1115                   }
1116               }
1117           }
1118         // For GOTPLT64, we'd normally want a PLT section, but since
1119         // we know this is a local symbol, no PLT is needed.
1120       }
1121       break;
1122
1123     case elfcpp::R_X86_64_COPY:
1124     case elfcpp::R_X86_64_GLOB_DAT:
1125     case elfcpp::R_X86_64_JUMP_SLOT:
1126     case elfcpp::R_X86_64_RELATIVE:
1127       // These are outstanding tls relocs, which are unexpected when linking
1128     case elfcpp::R_X86_64_TPOFF64:
1129     case elfcpp::R_X86_64_DTPMOD64:
1130     case elfcpp::R_X86_64_TLSDESC:
1131       gold_error(_("%s: unexpected reloc %u in object file"),
1132                  object->name().c_str(), r_type);
1133       break;
1134
1135       // These are initial tls relocs, which are expected when linking
1136     case elfcpp::R_X86_64_TLSGD:            // Global-dynamic
1137     case elfcpp::R_X86_64_GOTPC32_TLSDESC:  // Global-dynamic (from ~oliva url)
1138     case elfcpp::R_X86_64_TLSDESC_CALL:
1139     case elfcpp::R_X86_64_TLSLD:            // Local-dynamic
1140     case elfcpp::R_X86_64_DTPOFF32:
1141     case elfcpp::R_X86_64_DTPOFF64:
1142     case elfcpp::R_X86_64_GOTTPOFF:         // Initial-exec
1143     case elfcpp::R_X86_64_TPOFF32:          // Local-exec
1144       {
1145         bool output_is_shared = parameters->options().shared();
1146         const tls::Tls_optimization optimized_type
1147             = Target_x86_64::optimize_tls_reloc(!output_is_shared, r_type);
1148         switch (r_type)
1149           {
1150           case elfcpp::R_X86_64_TLSGD:       // General-dynamic
1151             if (optimized_type == tls::TLSOPT_NONE)
1152               {
1153                 // Create a pair of GOT entries for the module index and
1154                 // dtv-relative offset.
1155                 Output_data_got<64, false>* got
1156                     = target->got_section(symtab, layout);
1157                 unsigned int r_sym = elfcpp::elf_r_sym<64>(reloc.get_r_info());
1158                 unsigned int shndx = lsym.get_st_shndx();
1159                 bool is_ordinary;
1160                 shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
1161                 if (!is_ordinary)
1162                   object->error(_("local symbol %u has bad shndx %u"),
1163                               r_sym, shndx);
1164                 else
1165                   got->add_local_pair_with_rela(object, r_sym,
1166                                                 shndx,
1167                                                 GOT_TYPE_TLS_PAIR,
1168                                                 target->rela_dyn_section(layout),
1169                                                 elfcpp::R_X86_64_DTPMOD64, 0);
1170               }
1171             else if (optimized_type != tls::TLSOPT_TO_LE)
1172               unsupported_reloc_local(object, r_type);
1173             break;
1174
1175           case elfcpp::R_X86_64_GOTPC32_TLSDESC:
1176             target->define_tls_base_symbol(symtab, layout);
1177             if (optimized_type == tls::TLSOPT_NONE)
1178               {
1179                 // Create reserved PLT and GOT entries for the resolver.
1180                 target->reserve_tlsdesc_entries(symtab, layout);
1181
1182                 // Generate a double GOT entry with an R_X86_64_TLSDESC reloc.
1183                 Output_data_got<64, false>* got
1184                     = target->got_section(symtab, layout);
1185                 unsigned int r_sym = elfcpp::elf_r_sym<64>(reloc.get_r_info());
1186                 unsigned int shndx = lsym.get_st_shndx();
1187                 bool is_ordinary;
1188                 shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
1189                 if (!is_ordinary)
1190                   object->error(_("local symbol %u has bad shndx %u"),
1191                               r_sym, shndx);
1192                 else
1193                   got->add_local_pair_with_rela(object, r_sym,
1194                                                 shndx,
1195                                                 GOT_TYPE_TLS_DESC,
1196                                                 target->rela_dyn_section(layout),
1197                                                 elfcpp::R_X86_64_TLSDESC, 0);
1198               }
1199             else if (optimized_type != tls::TLSOPT_TO_LE)
1200               unsupported_reloc_local(object, r_type);
1201             break;
1202
1203           case elfcpp::R_X86_64_TLSDESC_CALL:
1204             break;
1205
1206           case elfcpp::R_X86_64_TLSLD:       // Local-dynamic
1207             if (optimized_type == tls::TLSOPT_NONE)
1208               {
1209                 // Create a GOT entry for the module index.
1210                 target->got_mod_index_entry(symtab, layout, object);
1211               }
1212             else if (optimized_type != tls::TLSOPT_TO_LE)
1213               unsupported_reloc_local(object, r_type);
1214             break;
1215
1216           case elfcpp::R_X86_64_DTPOFF32:
1217           case elfcpp::R_X86_64_DTPOFF64:
1218             break;
1219
1220           case elfcpp::R_X86_64_GOTTPOFF:    // Initial-exec
1221             layout->set_has_static_tls();
1222             if (optimized_type == tls::TLSOPT_NONE)
1223               {
1224                 // Create a GOT entry for the tp-relative offset.
1225                 Output_data_got<64, false>* got
1226                     = target->got_section(symtab, layout);
1227                 unsigned int r_sym = elfcpp::elf_r_sym<64>(reloc.get_r_info());
1228                 got->add_local_with_rela(object, r_sym, GOT_TYPE_TLS_OFFSET,
1229                                          target->rela_dyn_section(layout),
1230                                          elfcpp::R_X86_64_TPOFF64);
1231               }
1232             else if (optimized_type != tls::TLSOPT_TO_LE)
1233               unsupported_reloc_local(object, r_type);
1234             break;
1235
1236           case elfcpp::R_X86_64_TPOFF32:     // Local-exec
1237             layout->set_has_static_tls();
1238             if (output_is_shared)
1239               unsupported_reloc_local(object, r_type);
1240             break;
1241
1242           default:
1243             gold_unreachable();
1244           }
1245       }
1246       break;
1247
1248     case elfcpp::R_X86_64_SIZE32:
1249     case elfcpp::R_X86_64_SIZE64:
1250     default:
1251       gold_error(_("%s: unsupported reloc %u against local symbol"),
1252                  object->name().c_str(), r_type);
1253       break;
1254     }
1255 }
1256
1257
1258 // Report an unsupported relocation against a global symbol.
1259
1260 void
1261 Target_x86_64::Scan::unsupported_reloc_global(Sized_relobj<64, false>* object,
1262                                               unsigned int r_type,
1263                                               Symbol* gsym)
1264 {
1265   gold_error(_("%s: unsupported reloc %u against global symbol %s"),
1266              object->name().c_str(), r_type, gsym->demangled_name().c_str());
1267 }
1268
1269 // Scan a relocation for a global symbol.
1270
1271 inline void
1272 Target_x86_64::Scan::global(const General_options&,
1273                             Symbol_table* symtab,
1274                             Layout* layout,
1275                             Target_x86_64* target,
1276                             Sized_relobj<64, false>* object,
1277                             unsigned int data_shndx,
1278                             Output_section* output_section,
1279                             const elfcpp::Rela<64, false>& reloc,
1280                             unsigned int r_type,
1281                             Symbol* gsym)
1282 {
1283   switch (r_type)
1284     {
1285     case elfcpp::R_X86_64_NONE:
1286     case elfcpp::R_386_GNU_VTINHERIT:
1287     case elfcpp::R_386_GNU_VTENTRY:
1288       break;
1289
1290     case elfcpp::R_X86_64_64:
1291     case elfcpp::R_X86_64_32:
1292     case elfcpp::R_X86_64_32S:
1293     case elfcpp::R_X86_64_16:
1294     case elfcpp::R_X86_64_8:
1295       {
1296         // Make a PLT entry if necessary.
1297         if (gsym->needs_plt_entry())
1298           {
1299             target->make_plt_entry(symtab, layout, gsym);
1300             // Since this is not a PC-relative relocation, we may be
1301             // taking the address of a function. In that case we need to
1302             // set the entry in the dynamic symbol table to the address of
1303             // the PLT entry.
1304             if (gsym->is_from_dynobj() && !parameters->options().shared())
1305               gsym->set_needs_dynsym_value();
1306           }
1307         // Make a dynamic relocation if necessary.
1308         if (gsym->needs_dynamic_reloc(Symbol::ABSOLUTE_REF))
1309           {
1310             if (target->may_need_copy_reloc(gsym))
1311               {
1312                 target->copy_reloc(symtab, layout, object,
1313                                    data_shndx, output_section, gsym, reloc);
1314               }
1315             else if (r_type == elfcpp::R_X86_64_64
1316                      && gsym->can_use_relative_reloc(false))
1317               {
1318                 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
1319                 rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_RELATIVE,
1320                                               output_section, object,
1321                                               data_shndx, reloc.get_r_offset(),
1322                                               reloc.get_r_addend());
1323               }
1324             else
1325               {
1326                 this->check_non_pic(object, r_type);
1327                 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
1328                 rela_dyn->add_global(gsym, r_type, output_section, object,
1329                                      data_shndx, reloc.get_r_offset(),
1330                                      reloc.get_r_addend());
1331               }
1332           }
1333       }
1334       break;
1335
1336     case elfcpp::R_X86_64_PC64:
1337     case elfcpp::R_X86_64_PC32:
1338     case elfcpp::R_X86_64_PC16:
1339     case elfcpp::R_X86_64_PC8:
1340       {
1341         // Make a PLT entry if necessary.
1342         if (gsym->needs_plt_entry())
1343           target->make_plt_entry(symtab, layout, gsym);
1344         // Make a dynamic relocation if necessary.
1345         int flags = Symbol::NON_PIC_REF;
1346         if (gsym->type() == elfcpp::STT_FUNC)
1347           flags |= Symbol::FUNCTION_CALL;
1348         if (gsym->needs_dynamic_reloc(flags))
1349           {
1350             if (target->may_need_copy_reloc(gsym))
1351               {
1352                 target->copy_reloc(symtab, layout, object,
1353                                    data_shndx, output_section, gsym, reloc);
1354               }
1355             else
1356               {
1357                 this->check_non_pic(object, r_type);
1358                 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
1359                 rela_dyn->add_global(gsym, r_type, output_section, object,
1360                                      data_shndx, reloc.get_r_offset(),
1361                                      reloc.get_r_addend());
1362               }
1363           }
1364       }
1365       break;
1366
1367     case elfcpp::R_X86_64_GOT64:
1368     case elfcpp::R_X86_64_GOT32:
1369     case elfcpp::R_X86_64_GOTPCREL64:
1370     case elfcpp::R_X86_64_GOTPCREL:
1371     case elfcpp::R_X86_64_GOTPLT64:
1372       {
1373         // The symbol requires a GOT entry.
1374         Output_data_got<64, false>* got = target->got_section(symtab, layout);
1375         if (gsym->final_value_is_known())
1376           got->add_global(gsym, GOT_TYPE_STANDARD);
1377         else
1378           {
1379             // If this symbol is not fully resolved, we need to add a
1380             // dynamic relocation for it.
1381             Reloc_section* rela_dyn = target->rela_dyn_section(layout);
1382             if (gsym->is_from_dynobj()
1383                 || gsym->is_undefined()
1384                 || gsym->is_preemptible())
1385               got->add_global_with_rela(gsym, GOT_TYPE_STANDARD, rela_dyn,
1386                                         elfcpp::R_X86_64_GLOB_DAT);
1387             else
1388               {
1389                 if (got->add_global(gsym, GOT_TYPE_STANDARD))
1390                   rela_dyn->add_global_relative(
1391                       gsym, elfcpp::R_X86_64_RELATIVE, got,
1392                       gsym->got_offset(GOT_TYPE_STANDARD), 0);
1393               }
1394           }
1395         // For GOTPLT64, we also need a PLT entry (but only if the
1396         // symbol is not fully resolved).
1397         if (r_type == elfcpp::R_X86_64_GOTPLT64
1398             && !gsym->final_value_is_known())
1399           target->make_plt_entry(symtab, layout, gsym);
1400       }
1401       break;
1402
1403     case elfcpp::R_X86_64_PLT32:
1404       // If the symbol is fully resolved, this is just a PC32 reloc.
1405       // Otherwise we need a PLT entry.
1406       if (gsym->final_value_is_known())
1407         break;
1408       // If building a shared library, we can also skip the PLT entry
1409       // if the symbol is defined in the output file and is protected
1410       // or hidden.
1411       if (gsym->is_defined()
1412           && !gsym->is_from_dynobj()
1413           && !gsym->is_preemptible())
1414         break;
1415       target->make_plt_entry(symtab, layout, gsym);
1416       break;
1417
1418     case elfcpp::R_X86_64_GOTPC32:
1419     case elfcpp::R_X86_64_GOTOFF64:
1420     case elfcpp::R_X86_64_GOTPC64:
1421     case elfcpp::R_X86_64_PLTOFF64:
1422       // We need a GOT section.
1423       target->got_section(symtab, layout);
1424       // For PLTOFF64, we also need a PLT entry (but only if the
1425       // symbol is not fully resolved).
1426       if (r_type == elfcpp::R_X86_64_PLTOFF64
1427           && !gsym->final_value_is_known())
1428         target->make_plt_entry(symtab, layout, gsym);
1429       break;
1430
1431     case elfcpp::R_X86_64_COPY:
1432     case elfcpp::R_X86_64_GLOB_DAT:
1433     case elfcpp::R_X86_64_JUMP_SLOT:
1434     case elfcpp::R_X86_64_RELATIVE:
1435       // These are outstanding tls relocs, which are unexpected when linking
1436     case elfcpp::R_X86_64_TPOFF64:
1437     case elfcpp::R_X86_64_DTPMOD64:
1438     case elfcpp::R_X86_64_TLSDESC:
1439       gold_error(_("%s: unexpected reloc %u in object file"),
1440                  object->name().c_str(), r_type);
1441       break;
1442
1443       // These are initial tls relocs, which are expected for global()
1444     case elfcpp::R_X86_64_TLSGD:            // Global-dynamic
1445     case elfcpp::R_X86_64_GOTPC32_TLSDESC:  // Global-dynamic (from ~oliva url)
1446     case elfcpp::R_X86_64_TLSDESC_CALL:
1447     case elfcpp::R_X86_64_TLSLD:            // Local-dynamic
1448     case elfcpp::R_X86_64_DTPOFF32:
1449     case elfcpp::R_X86_64_DTPOFF64:
1450     case elfcpp::R_X86_64_GOTTPOFF:         // Initial-exec
1451     case elfcpp::R_X86_64_TPOFF32:          // Local-exec
1452       {
1453         const bool is_final = gsym->final_value_is_known();
1454         const tls::Tls_optimization optimized_type
1455             = Target_x86_64::optimize_tls_reloc(is_final, r_type);
1456         switch (r_type)
1457           {
1458           case elfcpp::R_X86_64_TLSGD:       // General-dynamic
1459             if (optimized_type == tls::TLSOPT_NONE)
1460               {
1461                 // Create a pair of GOT entries for the module index and
1462                 // dtv-relative offset.
1463                 Output_data_got<64, false>* got
1464                     = target->got_section(symtab, layout);
1465                 got->add_global_pair_with_rela(gsym, GOT_TYPE_TLS_PAIR,
1466                                                target->rela_dyn_section(layout),
1467                                                elfcpp::R_X86_64_DTPMOD64,
1468                                                elfcpp::R_X86_64_DTPOFF64);
1469               }
1470             else if (optimized_type == tls::TLSOPT_TO_IE)
1471               {
1472                 // Create a GOT entry for the tp-relative offset.
1473                 Output_data_got<64, false>* got
1474                     = target->got_section(symtab, layout);
1475                 got->add_global_with_rela(gsym, GOT_TYPE_TLS_OFFSET,
1476                                           target->rela_dyn_section(layout),
1477                                           elfcpp::R_X86_64_TPOFF64);
1478               }
1479             else if (optimized_type != tls::TLSOPT_TO_LE)
1480               unsupported_reloc_global(object, r_type, gsym);
1481             break;
1482
1483           case elfcpp::R_X86_64_GOTPC32_TLSDESC:
1484             target->define_tls_base_symbol(symtab, layout);
1485             if (optimized_type == tls::TLSOPT_NONE)
1486               {
1487                 // Create reserved PLT and GOT entries for the resolver.
1488                 target->reserve_tlsdesc_entries(symtab, layout);
1489
1490                 // Create a double GOT entry with an R_X86_64_TLSDESC reloc.
1491                 Output_data_got<64, false>* got
1492                     = target->got_section(symtab, layout);
1493                 got->add_global_pair_with_rela(gsym, GOT_TYPE_TLS_DESC,
1494                                                target->rela_dyn_section(layout),
1495                                                elfcpp::R_X86_64_TLSDESC, 0);
1496               }
1497             else if (optimized_type == tls::TLSOPT_TO_IE)
1498               {
1499                 // Create a GOT entry for the tp-relative offset.
1500                 Output_data_got<64, false>* got
1501                     = target->got_section(symtab, layout);
1502                 got->add_global_with_rela(gsym, GOT_TYPE_TLS_OFFSET,
1503                                           target->rela_dyn_section(layout),
1504                                           elfcpp::R_X86_64_TPOFF64);
1505               }
1506             else if (optimized_type != tls::TLSOPT_TO_LE)
1507               unsupported_reloc_global(object, r_type, gsym);
1508             break;
1509
1510           case elfcpp::R_X86_64_TLSDESC_CALL:
1511             break;
1512
1513           case elfcpp::R_X86_64_TLSLD:       // Local-dynamic
1514             if (optimized_type == tls::TLSOPT_NONE)
1515               {
1516                 // Create a GOT entry for the module index.
1517                 target->got_mod_index_entry(symtab, layout, object);
1518               }
1519             else if (optimized_type != tls::TLSOPT_TO_LE)
1520               unsupported_reloc_global(object, r_type, gsym);
1521             break;
1522
1523           case elfcpp::R_X86_64_DTPOFF32:
1524           case elfcpp::R_X86_64_DTPOFF64:
1525             break;
1526
1527           case elfcpp::R_X86_64_GOTTPOFF:    // Initial-exec
1528             layout->set_has_static_tls();
1529             if (optimized_type == tls::TLSOPT_NONE)
1530               {
1531                 // Create a GOT entry for the tp-relative offset.
1532                 Output_data_got<64, false>* got
1533                     = target->got_section(symtab, layout);
1534                 got->add_global_with_rela(gsym, GOT_TYPE_TLS_OFFSET,
1535                                           target->rela_dyn_section(layout),
1536                                           elfcpp::R_X86_64_TPOFF64);
1537               }
1538             else if (optimized_type != tls::TLSOPT_TO_LE)
1539               unsupported_reloc_global(object, r_type, gsym);
1540             break;
1541
1542           case elfcpp::R_X86_64_TPOFF32:     // Local-exec
1543             layout->set_has_static_tls();
1544             if (parameters->options().shared())
1545               unsupported_reloc_local(object, r_type);
1546             break;
1547
1548           default:
1549             gold_unreachable();
1550           }
1551       }
1552       break;
1553
1554     case elfcpp::R_X86_64_SIZE32:
1555     case elfcpp::R_X86_64_SIZE64:
1556     default:
1557       gold_error(_("%s: unsupported reloc %u against global symbol %s"),
1558                  object->name().c_str(), r_type,
1559                  gsym->demangled_name().c_str());
1560       break;
1561     }
1562 }
1563
1564 void
1565 Target_x86_64::gc_process_relocs(const General_options& options,
1566                                  Symbol_table* symtab,
1567                                  Layout* layout,
1568                                  Sized_relobj<64, false>* object,
1569                                  unsigned int data_shndx,
1570                                  unsigned int sh_type,
1571                                  const unsigned char* prelocs,
1572                                  size_t reloc_count,
1573                                  Output_section* output_section,
1574                                  bool needs_special_offset_handling,
1575                                  size_t local_symbol_count,
1576                                  const unsigned char* plocal_symbols)
1577 {
1578
1579   if (sh_type == elfcpp::SHT_REL)
1580     {
1581       return;
1582     }
1583
1584    gold::gc_process_relocs<64, false, Target_x86_64, elfcpp::SHT_RELA,
1585                            Target_x86_64::Scan>(
1586     options,
1587     symtab,
1588     layout,
1589     this,
1590     object,
1591     data_shndx,
1592     prelocs,
1593     reloc_count,
1594     output_section,
1595     needs_special_offset_handling,
1596     local_symbol_count,
1597     plocal_symbols);
1598
1599 }
1600 // Scan relocations for a section.
1601
1602 void
1603 Target_x86_64::scan_relocs(const General_options& options,
1604                            Symbol_table* symtab,
1605                            Layout* layout,
1606                            Sized_relobj<64, false>* object,
1607                            unsigned int data_shndx,
1608                            unsigned int sh_type,
1609                            const unsigned char* prelocs,
1610                            size_t reloc_count,
1611                            Output_section* output_section,
1612                            bool needs_special_offset_handling,
1613                            size_t local_symbol_count,
1614                            const unsigned char* plocal_symbols)
1615 {
1616   if (sh_type == elfcpp::SHT_REL)
1617     {
1618       gold_error(_("%s: unsupported REL reloc section"),
1619                  object->name().c_str());
1620       return;
1621     }
1622
1623   gold::scan_relocs<64, false, Target_x86_64, elfcpp::SHT_RELA,
1624       Target_x86_64::Scan>(
1625     options,
1626     symtab,
1627     layout,
1628     this,
1629     object,
1630     data_shndx,
1631     prelocs,
1632     reloc_count,
1633     output_section,
1634     needs_special_offset_handling,
1635     local_symbol_count,
1636     plocal_symbols);
1637 }
1638
1639 // Finalize the sections.
1640
1641 void
1642 Target_x86_64::do_finalize_sections(Layout* layout)
1643 {
1644   // Fill in some more dynamic tags.
1645   Output_data_dynamic* const odyn = layout->dynamic_data();
1646   if (odyn != NULL)
1647     {
1648       if (this->got_plt_ != NULL)
1649         odyn->add_section_address(elfcpp::DT_PLTGOT, this->got_plt_);
1650
1651       if (this->plt_ != NULL)
1652         {
1653           const Output_data* od = this->plt_->rel_plt();
1654           odyn->add_section_size(elfcpp::DT_PLTRELSZ, od);
1655           odyn->add_section_address(elfcpp::DT_JMPREL, od);
1656           odyn->add_constant(elfcpp::DT_PLTREL, elfcpp::DT_RELA);
1657           if (this->plt_->has_tlsdesc_entry())
1658             {
1659               unsigned int plt_offset = this->plt_->get_tlsdesc_plt_offset();
1660               unsigned int got_offset = this->plt_->get_tlsdesc_got_offset();
1661               this->got_->finalize_data_size();
1662               odyn->add_section_plus_offset(elfcpp::DT_TLSDESC_PLT,
1663                                             this->plt_, plt_offset);
1664               odyn->add_section_plus_offset(elfcpp::DT_TLSDESC_GOT,
1665                                             this->got_, got_offset);
1666             }
1667         }
1668
1669       if (this->rela_dyn_ != NULL)
1670         {
1671           const Output_data* od = this->rela_dyn_;
1672           odyn->add_section_address(elfcpp::DT_RELA, od);
1673           odyn->add_section_size(elfcpp::DT_RELASZ, od);
1674           odyn->add_constant(elfcpp::DT_RELAENT,
1675                              elfcpp::Elf_sizes<64>::rela_size);
1676         }
1677
1678       if (!parameters->options().shared())
1679         {
1680           // The value of the DT_DEBUG tag is filled in by the dynamic
1681           // linker at run time, and used by the debugger.
1682           odyn->add_constant(elfcpp::DT_DEBUG, 0);
1683         }
1684     }
1685
1686   // Emit any relocs we saved in an attempt to avoid generating COPY
1687   // relocs.
1688   if (this->copy_relocs_.any_saved_relocs())
1689     this->copy_relocs_.emit(this->rela_dyn_section(layout));
1690 }
1691
1692 // Perform a relocation.
1693
1694 inline bool
1695 Target_x86_64::Relocate::relocate(const Relocate_info<64, false>* relinfo,
1696                                   Target_x86_64* target,
1697                                   Output_section*,
1698                                   size_t relnum,
1699                                   const elfcpp::Rela<64, false>& rela,
1700                                   unsigned int r_type,
1701                                   const Sized_symbol<64>* gsym,
1702                                   const Symbol_value<64>* psymval,
1703                                   unsigned char* view,
1704                                   elfcpp::Elf_types<64>::Elf_Addr address,
1705                                   section_size_type view_size)
1706 {
1707   if (this->skip_call_tls_get_addr_)
1708     {
1709       if ((r_type != elfcpp::R_X86_64_PLT32
1710            && r_type != elfcpp::R_X86_64_PC32)
1711           || gsym == NULL
1712           || strcmp(gsym->name(), "__tls_get_addr") != 0)
1713         {
1714           gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
1715                                  _("missing expected TLS relocation"));
1716         }
1717       else
1718         {
1719           this->skip_call_tls_get_addr_ = false;
1720           return false;
1721         }
1722     }
1723
1724   // Pick the value to use for symbols defined in shared objects.
1725   Symbol_value<64> symval;
1726   if (gsym != NULL
1727       && gsym->use_plt_offset(r_type == elfcpp::R_X86_64_PC64
1728                               || r_type == elfcpp::R_X86_64_PC32
1729                               || r_type == elfcpp::R_X86_64_PC16
1730                               || r_type == elfcpp::R_X86_64_PC8))
1731     {
1732       symval.set_output_value(target->plt_section()->address()
1733                               + gsym->plt_offset());
1734       psymval = &symval;
1735     }
1736
1737   const Sized_relobj<64, false>* object = relinfo->object;
1738   const elfcpp::Elf_Xword addend = rela.get_r_addend();
1739
1740   // Get the GOT offset if needed.
1741   // The GOT pointer points to the end of the GOT section.
1742   // We need to subtract the size of the GOT section to get
1743   // the actual offset to use in the relocation.
1744   bool have_got_offset = false;
1745   unsigned int got_offset = 0;
1746   switch (r_type)
1747     {
1748     case elfcpp::R_X86_64_GOT32:
1749     case elfcpp::R_X86_64_GOT64:
1750     case elfcpp::R_X86_64_GOTPLT64:
1751     case elfcpp::R_X86_64_GOTPCREL:
1752     case elfcpp::R_X86_64_GOTPCREL64:
1753       if (gsym != NULL)
1754         {
1755           gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
1756           got_offset = gsym->got_offset(GOT_TYPE_STANDARD) - target->got_size();
1757         }
1758       else
1759         {
1760           unsigned int r_sym = elfcpp::elf_r_sym<64>(rela.get_r_info());
1761           gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD));
1762           got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD)
1763                         - target->got_size());
1764         }
1765       have_got_offset = true;
1766       break;
1767
1768     default:
1769       break;
1770     }
1771
1772   switch (r_type)
1773     {
1774     case elfcpp::R_X86_64_NONE:
1775     case elfcpp::R_386_GNU_VTINHERIT:
1776     case elfcpp::R_386_GNU_VTENTRY:
1777       break;
1778
1779     case elfcpp::R_X86_64_64:
1780       Relocate_functions<64, false>::rela64(view, object, psymval, addend);
1781       break;
1782
1783     case elfcpp::R_X86_64_PC64:
1784       Relocate_functions<64, false>::pcrela64(view, object, psymval, addend,
1785                                               address);
1786       break;
1787
1788     case elfcpp::R_X86_64_32:
1789       // FIXME: we need to verify that value + addend fits into 32 bits:
1790       //    uint64_t x = value + addend;
1791       //    x == static_cast<uint64_t>(static_cast<uint32_t>(x))
1792       // Likewise for other <=32-bit relocations (but see R_X86_64_32S).
1793       Relocate_functions<64, false>::rela32(view, object, psymval, addend);
1794       break;
1795
1796     case elfcpp::R_X86_64_32S:
1797       // FIXME: we need to verify that value + addend fits into 32 bits:
1798       //    int64_t x = value + addend;   // note this quantity is signed!
1799       //    x == static_cast<int64_t>(static_cast<int32_t>(x))
1800       Relocate_functions<64, false>::rela32(view, object, psymval, addend);
1801       break;
1802
1803     case elfcpp::R_X86_64_PC32:
1804       Relocate_functions<64, false>::pcrela32(view, object, psymval, addend,
1805                                               address);
1806       break;
1807
1808     case elfcpp::R_X86_64_16:
1809       Relocate_functions<64, false>::rela16(view, object, psymval, addend);
1810       break;
1811
1812     case elfcpp::R_X86_64_PC16:
1813       Relocate_functions<64, false>::pcrela16(view, object, psymval, addend,
1814                                               address);
1815       break;
1816
1817     case elfcpp::R_X86_64_8:
1818       Relocate_functions<64, false>::rela8(view, object, psymval, addend);
1819       break;
1820
1821     case elfcpp::R_X86_64_PC8:
1822       Relocate_functions<64, false>::pcrela8(view, object, psymval, addend,
1823                                              address);
1824       break;
1825
1826     case elfcpp::R_X86_64_PLT32:
1827       gold_assert(gsym == NULL
1828                   || gsym->has_plt_offset()
1829                   || gsym->final_value_is_known()
1830                   || (gsym->is_defined()
1831                       && !gsym->is_from_dynobj()
1832                       && !gsym->is_preemptible()));
1833       // Note: while this code looks the same as for R_X86_64_PC32, it
1834       // behaves differently because psymval was set to point to
1835       // the PLT entry, rather than the symbol, in Scan::global().
1836       Relocate_functions<64, false>::pcrela32(view, object, psymval, addend,
1837                                               address);
1838       break;
1839
1840     case elfcpp::R_X86_64_PLTOFF64:
1841       {
1842         gold_assert(gsym);
1843         gold_assert(gsym->has_plt_offset()
1844                     || gsym->final_value_is_known());
1845         elfcpp::Elf_types<64>::Elf_Addr got_address;
1846         got_address = target->got_section(NULL, NULL)->address();
1847         Relocate_functions<64, false>::rela64(view, object, psymval,
1848                                               addend - got_address);
1849       }
1850
1851     case elfcpp::R_X86_64_GOT32:
1852       gold_assert(have_got_offset);
1853       Relocate_functions<64, false>::rela32(view, got_offset, addend);
1854       break;
1855
1856     case elfcpp::R_X86_64_GOTPC32:
1857       {
1858         gold_assert(gsym);
1859         elfcpp::Elf_types<64>::Elf_Addr value;
1860         value = target->got_plt_section()->address();
1861         Relocate_functions<64, false>::pcrela32(view, value, addend, address);
1862       }
1863       break;
1864
1865     case elfcpp::R_X86_64_GOT64:
1866       // The ABI doc says "Like GOT64, but indicates a PLT entry is needed."
1867       // Since we always add a PLT entry, this is equivalent.
1868     case elfcpp::R_X86_64_GOTPLT64:
1869       gold_assert(have_got_offset);
1870       Relocate_functions<64, false>::rela64(view, got_offset, addend);
1871       break;
1872
1873     case elfcpp::R_X86_64_GOTPC64:
1874       {
1875         gold_assert(gsym);
1876         elfcpp::Elf_types<64>::Elf_Addr value;
1877         value = target->got_plt_section()->address();
1878         Relocate_functions<64, false>::pcrela64(view, value, addend, address);
1879       }
1880       break;
1881
1882     case elfcpp::R_X86_64_GOTOFF64:
1883       {
1884         elfcpp::Elf_types<64>::Elf_Addr value;
1885         value = (psymval->value(object, 0)
1886                  - target->got_plt_section()->address());
1887         Relocate_functions<64, false>::rela64(view, value, addend);
1888       }
1889       break;
1890
1891     case elfcpp::R_X86_64_GOTPCREL:
1892       {
1893         gold_assert(have_got_offset);
1894         elfcpp::Elf_types<64>::Elf_Addr value;
1895         value = target->got_plt_section()->address() + got_offset;
1896         Relocate_functions<64, false>::pcrela32(view, value, addend, address);
1897       }
1898       break;
1899
1900     case elfcpp::R_X86_64_GOTPCREL64:
1901       {
1902         gold_assert(have_got_offset);
1903         elfcpp::Elf_types<64>::Elf_Addr value;
1904         value = target->got_plt_section()->address() + got_offset;
1905         Relocate_functions<64, false>::pcrela64(view, value, addend, address);
1906       }
1907       break;
1908
1909     case elfcpp::R_X86_64_COPY:
1910     case elfcpp::R_X86_64_GLOB_DAT:
1911     case elfcpp::R_X86_64_JUMP_SLOT:
1912     case elfcpp::R_X86_64_RELATIVE:
1913       // These are outstanding tls relocs, which are unexpected when linking
1914     case elfcpp::R_X86_64_TPOFF64:
1915     case elfcpp::R_X86_64_DTPMOD64:
1916     case elfcpp::R_X86_64_TLSDESC:
1917       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
1918                              _("unexpected reloc %u in object file"),
1919                              r_type);
1920       break;
1921
1922       // These are initial tls relocs, which are expected when linking
1923     case elfcpp::R_X86_64_TLSGD:            // Global-dynamic
1924     case elfcpp::R_X86_64_GOTPC32_TLSDESC:  // Global-dynamic (from ~oliva url)
1925     case elfcpp::R_X86_64_TLSDESC_CALL:
1926     case elfcpp::R_X86_64_TLSLD:            // Local-dynamic
1927     case elfcpp::R_X86_64_DTPOFF32:
1928     case elfcpp::R_X86_64_DTPOFF64:
1929     case elfcpp::R_X86_64_GOTTPOFF:         // Initial-exec
1930     case elfcpp::R_X86_64_TPOFF32:          // Local-exec
1931       this->relocate_tls(relinfo, target, relnum, rela, r_type, gsym, psymval,
1932                          view, address, view_size);
1933       break;
1934
1935     case elfcpp::R_X86_64_SIZE32:
1936     case elfcpp::R_X86_64_SIZE64:
1937     default:
1938       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
1939                              _("unsupported reloc %u"),
1940                              r_type);
1941       break;
1942     }
1943
1944   return true;
1945 }
1946
1947 // Perform a TLS relocation.
1948
1949 inline void
1950 Target_x86_64::Relocate::relocate_tls(const Relocate_info<64, false>* relinfo,
1951                                       Target_x86_64* target,
1952                                       size_t relnum,
1953                                       const elfcpp::Rela<64, false>& rela,
1954                                       unsigned int r_type,
1955                                       const Sized_symbol<64>* gsym,
1956                                       const Symbol_value<64>* psymval,
1957                                       unsigned char* view,
1958                                       elfcpp::Elf_types<64>::Elf_Addr address,
1959                                       section_size_type view_size)
1960 {
1961   Output_segment* tls_segment = relinfo->layout->tls_segment();
1962
1963   const Sized_relobj<64, false>* object = relinfo->object;
1964   const elfcpp::Elf_Xword addend = rela.get_r_addend();
1965
1966   elfcpp::Elf_types<64>::Elf_Addr value = psymval->value(relinfo->object, 0);
1967
1968   const bool is_final = (gsym == NULL
1969                          ? !parameters->options().output_is_position_independent()
1970                          : gsym->final_value_is_known());
1971   const tls::Tls_optimization optimized_type
1972       = Target_x86_64::optimize_tls_reloc(is_final, r_type);
1973   switch (r_type)
1974     {
1975     case elfcpp::R_X86_64_TLSGD:            // Global-dynamic
1976       this->saw_tls_block_reloc_ = true;
1977       if (optimized_type == tls::TLSOPT_TO_LE)
1978         {
1979           gold_assert(tls_segment != NULL);
1980           this->tls_gd_to_le(relinfo, relnum, tls_segment,
1981                              rela, r_type, value, view,
1982                              view_size);
1983           break;
1984         }
1985       else
1986         {
1987           unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE
1988                                    ? GOT_TYPE_TLS_OFFSET
1989                                    : GOT_TYPE_TLS_PAIR);
1990           unsigned int got_offset;
1991           if (gsym != NULL)
1992             {
1993               gold_assert(gsym->has_got_offset(got_type));
1994               got_offset = gsym->got_offset(got_type) - target->got_size();
1995             }
1996           else
1997             {
1998               unsigned int r_sym = elfcpp::elf_r_sym<64>(rela.get_r_info());
1999               gold_assert(object->local_has_got_offset(r_sym, got_type));
2000               got_offset = (object->local_got_offset(r_sym, got_type)
2001                             - target->got_size());
2002             }
2003           if (optimized_type == tls::TLSOPT_TO_IE)
2004             {
2005               gold_assert(tls_segment != NULL);
2006               value = target->got_plt_section()->address() + got_offset;
2007               this->tls_gd_to_ie(relinfo, relnum, tls_segment, rela, r_type,
2008                                  value, view, address, view_size);
2009               break;
2010             }
2011           else if (optimized_type == tls::TLSOPT_NONE)
2012             {
2013               // Relocate the field with the offset of the pair of GOT
2014               // entries.
2015               value = target->got_plt_section()->address() + got_offset;
2016               Relocate_functions<64, false>::pcrela32(view, value, addend,
2017                                                       address);
2018               break;
2019             }
2020         }
2021       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
2022                              _("unsupported reloc %u"), r_type);
2023       break;
2024
2025     case elfcpp::R_X86_64_GOTPC32_TLSDESC:  // Global-dynamic (from ~oliva url)
2026     case elfcpp::R_X86_64_TLSDESC_CALL:
2027       this->saw_tls_block_reloc_ = true;
2028       if (optimized_type == tls::TLSOPT_TO_LE)
2029         {
2030           gold_assert(tls_segment != NULL);
2031           this->tls_desc_gd_to_le(relinfo, relnum, tls_segment,
2032                                   rela, r_type, value, view,
2033                                   view_size);
2034           break;
2035         }
2036       else
2037         {
2038           unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE
2039                                    ? GOT_TYPE_TLS_OFFSET
2040                                    : GOT_TYPE_TLS_DESC);
2041           unsigned int got_offset;
2042           if (gsym != NULL)
2043             {
2044               gold_assert(gsym->has_got_offset(got_type));
2045               got_offset = gsym->got_offset(got_type) - target->got_size();
2046             }
2047           else
2048             {
2049               unsigned int r_sym = elfcpp::elf_r_sym<64>(rela.get_r_info());
2050               gold_assert(object->local_has_got_offset(r_sym, got_type));
2051               got_offset = (object->local_got_offset(r_sym, got_type)
2052                             - target->got_size());
2053             }
2054           if (optimized_type == tls::TLSOPT_TO_IE)
2055             {
2056               gold_assert(tls_segment != NULL);
2057               value = target->got_plt_section()->address() + got_offset;
2058               this->tls_desc_gd_to_ie(relinfo, relnum, tls_segment,
2059                                       rela, r_type, value, view, address,
2060                                       view_size);
2061               break;
2062             }
2063           else if (optimized_type == tls::TLSOPT_NONE)
2064             {
2065               if (r_type == elfcpp::R_X86_64_GOTPC32_TLSDESC)
2066                 {
2067                   // Relocate the field with the offset of the pair of GOT
2068                   // entries.
2069                   value = target->got_plt_section()->address() + got_offset;
2070                   Relocate_functions<64, false>::pcrela32(view, value, addend,
2071                                                           address);
2072                 }
2073               break;
2074             }
2075         }
2076       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
2077                              _("unsupported reloc %u"), r_type);
2078       break;
2079
2080     case elfcpp::R_X86_64_TLSLD:            // Local-dynamic
2081       this->saw_tls_block_reloc_ = true;
2082       if (optimized_type == tls::TLSOPT_TO_LE)
2083         {
2084           gold_assert(tls_segment != NULL);
2085           this->tls_ld_to_le(relinfo, relnum, tls_segment, rela, r_type,
2086                              value, view, view_size);
2087           break;
2088         }
2089       else if (optimized_type == tls::TLSOPT_NONE)
2090         {
2091           // Relocate the field with the offset of the GOT entry for
2092           // the module index.
2093           unsigned int got_offset;
2094           got_offset = (target->got_mod_index_entry(NULL, NULL, NULL)
2095                         - target->got_size());
2096           value = target->got_plt_section()->address() + got_offset;
2097           Relocate_functions<64, false>::pcrela32(view, value, addend,
2098                                                   address);
2099           break;
2100         }
2101       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
2102                              _("unsupported reloc %u"), r_type);
2103       break;
2104
2105     case elfcpp::R_X86_64_DTPOFF32:
2106       gold_assert(tls_segment != NULL);
2107       if (optimized_type == tls::TLSOPT_TO_LE)
2108         {
2109           // This relocation type is used in debugging information.
2110           // In that case we need to not optimize the value.  If we
2111           // haven't seen a TLSLD reloc, then we assume we should not
2112           // optimize this reloc.
2113           if (this->saw_tls_block_reloc_)
2114             value -= tls_segment->memsz();
2115         }
2116       Relocate_functions<64, false>::rela32(view, value, addend);
2117       break;
2118
2119     case elfcpp::R_X86_64_DTPOFF64:
2120       gold_assert(tls_segment != NULL);
2121       if (optimized_type == tls::TLSOPT_TO_LE)
2122         {
2123           // See R_X86_64_DTPOFF32, just above, for why we test this.
2124           if (this->saw_tls_block_reloc_)
2125             value -= tls_segment->memsz();
2126         }
2127       Relocate_functions<64, false>::rela64(view, value, addend);
2128       break;
2129
2130     case elfcpp::R_X86_64_GOTTPOFF:         // Initial-exec
2131       if (optimized_type == tls::TLSOPT_TO_LE)
2132         {
2133           gold_assert(tls_segment != NULL);
2134           Target_x86_64::Relocate::tls_ie_to_le(relinfo, relnum, tls_segment,
2135                                                 rela, r_type, value, view,
2136                                                 view_size);
2137           break;
2138         }
2139       else if (optimized_type == tls::TLSOPT_NONE)
2140         {
2141           // Relocate the field with the offset of the GOT entry for
2142           // the tp-relative offset of the symbol.
2143           unsigned int got_offset;
2144           if (gsym != NULL)
2145             {
2146               gold_assert(gsym->has_got_offset(GOT_TYPE_TLS_OFFSET));
2147               got_offset = (gsym->got_offset(GOT_TYPE_TLS_OFFSET)
2148                             - target->got_size());
2149             }
2150           else
2151             {
2152               unsigned int r_sym = elfcpp::elf_r_sym<64>(rela.get_r_info());
2153               gold_assert(object->local_has_got_offset(r_sym,
2154                                                        GOT_TYPE_TLS_OFFSET));
2155               got_offset = (object->local_got_offset(r_sym, GOT_TYPE_TLS_OFFSET)
2156                             - target->got_size());
2157             }
2158           value = target->got_plt_section()->address() + got_offset;
2159           Relocate_functions<64, false>::pcrela32(view, value, addend, address);
2160           break;
2161         }
2162       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
2163                              _("unsupported reloc type %u"),
2164                              r_type);
2165       break;
2166
2167     case elfcpp::R_X86_64_TPOFF32:          // Local-exec
2168       value -= tls_segment->memsz();
2169       Relocate_functions<64, false>::rela32(view, value, addend);
2170       break;
2171     }
2172 }
2173
2174 // Do a relocation in which we convert a TLS General-Dynamic to an
2175 // Initial-Exec.
2176
2177 inline void
2178 Target_x86_64::Relocate::tls_gd_to_ie(const Relocate_info<64, false>* relinfo,
2179                                       size_t relnum,
2180                                       Output_segment*,
2181                                       const elfcpp::Rela<64, false>& rela,
2182                                       unsigned int,
2183                                       elfcpp::Elf_types<64>::Elf_Addr value,
2184                                       unsigned char* view,
2185                                       elfcpp::Elf_types<64>::Elf_Addr address,
2186                                       section_size_type view_size)
2187 {
2188   // .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
2189   // .word 0x6666; rex64; call __tls_get_addr
2190   // ==> movq %fs:0,%rax; addq x@gottpoff(%rip),%rax
2191
2192   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -4);
2193   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 12);
2194
2195   tls::check_tls(relinfo, relnum, rela.get_r_offset(),
2196                  (memcmp(view - 4, "\x66\x48\x8d\x3d", 4) == 0));
2197   tls::check_tls(relinfo, relnum, rela.get_r_offset(),
2198                  (memcmp(view + 4, "\x66\x66\x48\xe8", 4) == 0));
2199
2200   memcpy(view - 4, "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x03\x05\0\0\0\0", 16);
2201
2202   const elfcpp::Elf_Xword addend = rela.get_r_addend();
2203   Relocate_functions<64, false>::pcrela32(view + 8, value, addend - 8, address);
2204
2205   // The next reloc should be a PLT32 reloc against __tls_get_addr.
2206   // We can skip it.
2207   this->skip_call_tls_get_addr_ = true;
2208 }
2209
2210 // Do a relocation in which we convert a TLS General-Dynamic to a
2211 // Local-Exec.
2212
2213 inline void
2214 Target_x86_64::Relocate::tls_gd_to_le(const Relocate_info<64, false>* relinfo,
2215                                       size_t relnum,
2216                                       Output_segment* tls_segment,
2217                                       const elfcpp::Rela<64, false>& rela,
2218                                       unsigned int,
2219                                       elfcpp::Elf_types<64>::Elf_Addr value,
2220                                       unsigned char* view,
2221                                       section_size_type view_size)
2222 {
2223   // .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
2224   // .word 0x6666; rex64; call __tls_get_addr
2225   // ==> movq %fs:0,%rax; leaq x@tpoff(%rax),%rax
2226
2227   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -4);
2228   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 12);
2229
2230   tls::check_tls(relinfo, relnum, rela.get_r_offset(),
2231                  (memcmp(view - 4, "\x66\x48\x8d\x3d", 4) == 0));
2232   tls::check_tls(relinfo, relnum, rela.get_r_offset(),
2233                  (memcmp(view + 4, "\x66\x66\x48\xe8", 4) == 0));
2234
2235   memcpy(view - 4, "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0\0", 16);
2236
2237   value -= tls_segment->memsz();
2238   Relocate_functions<64, false>::rela32(view + 8, value, 0);
2239
2240   // The next reloc should be a PLT32 reloc against __tls_get_addr.
2241   // We can skip it.
2242   this->skip_call_tls_get_addr_ = true;
2243 }
2244
2245 // Do a TLSDESC-style General-Dynamic to Initial-Exec transition.
2246
2247 inline void
2248 Target_x86_64::Relocate::tls_desc_gd_to_ie(
2249     const Relocate_info<64, false>* relinfo,
2250     size_t relnum,
2251     Output_segment*,
2252     const elfcpp::Rela<64, false>& rela,
2253     unsigned int r_type,
2254     elfcpp::Elf_types<64>::Elf_Addr value,
2255     unsigned char* view,
2256     elfcpp::Elf_types<64>::Elf_Addr address,
2257     section_size_type view_size)
2258 {
2259   if (r_type == elfcpp::R_X86_64_GOTPC32_TLSDESC)
2260     {
2261       // leaq foo@tlsdesc(%rip), %rax
2262       // ==> movq foo@gottpoff(%rip), %rax
2263       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -3);
2264       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 4);
2265       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
2266                      view[-3] == 0x48 && view[-2] == 0x8d && view[-1] == 0x05);
2267       view[-2] = 0x8b;
2268       const elfcpp::Elf_Xword addend = rela.get_r_addend();
2269       Relocate_functions<64, false>::pcrela32(view, value, addend, address);
2270     }
2271   else
2272     {
2273       // call *foo@tlscall(%rax)
2274       // ==> nop; nop
2275       gold_assert(r_type == elfcpp::R_X86_64_TLSDESC_CALL);
2276       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 2);
2277       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
2278                      view[0] == 0xff && view[1] == 0x10);
2279       view[0] = 0x66;
2280       view[1] = 0x90;
2281     }
2282 }
2283
2284 // Do a TLSDESC-style General-Dynamic to Local-Exec transition.
2285
2286 inline void
2287 Target_x86_64::Relocate::tls_desc_gd_to_le(
2288     const Relocate_info<64, false>* relinfo,
2289     size_t relnum,
2290     Output_segment* tls_segment,
2291     const elfcpp::Rela<64, false>& rela,
2292     unsigned int r_type,
2293     elfcpp::Elf_types<64>::Elf_Addr value,
2294     unsigned char* view,
2295     section_size_type view_size)
2296 {
2297   if (r_type == elfcpp::R_X86_64_GOTPC32_TLSDESC)
2298     {
2299       // leaq foo@tlsdesc(%rip), %rax
2300       // ==> movq foo@tpoff, %rax
2301       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -3);
2302       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 4);
2303       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
2304                      view[-3] == 0x48 && view[-2] == 0x8d && view[-1] == 0x05);
2305       view[-2] = 0xc7;
2306       view[-1] = 0xc0;
2307       value -= tls_segment->memsz();
2308       Relocate_functions<64, false>::rela32(view, value, 0);
2309     }
2310   else
2311     {
2312       // call *foo@tlscall(%rax)
2313       // ==> nop; nop
2314       gold_assert(r_type == elfcpp::R_X86_64_TLSDESC_CALL);
2315       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 2);
2316       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
2317                      view[0] == 0xff && view[1] == 0x10);
2318       view[0] = 0x66;
2319       view[1] = 0x90;
2320     }
2321 }
2322
2323 inline void
2324 Target_x86_64::Relocate::tls_ld_to_le(const Relocate_info<64, false>* relinfo,
2325                                       size_t relnum,
2326                                       Output_segment*,
2327                                       const elfcpp::Rela<64, false>& rela,
2328                                       unsigned int,
2329                                       elfcpp::Elf_types<64>::Elf_Addr,
2330                                       unsigned char* view,
2331                                       section_size_type view_size)
2332 {
2333   // leaq foo@tlsld(%rip),%rdi; call __tls_get_addr@plt;
2334   // ... leq foo@dtpoff(%rax),%reg
2335   // ==> .word 0x6666; .byte 0x66; movq %fs:0,%rax ... leaq x@tpoff(%rax),%rdx
2336
2337   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -3);
2338   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 9);
2339
2340   tls::check_tls(relinfo, relnum, rela.get_r_offset(),
2341                  view[-3] == 0x48 && view[-2] == 0x8d && view[-1] == 0x3d);
2342
2343   tls::check_tls(relinfo, relnum, rela.get_r_offset(), view[4] == 0xe8);
2344
2345   memcpy(view - 3, "\x66\x66\x66\x64\x48\x8b\x04\x25\0\0\0\0", 12);
2346
2347   // The next reloc should be a PLT32 reloc against __tls_get_addr.
2348   // We can skip it.
2349   this->skip_call_tls_get_addr_ = true;
2350 }
2351
2352 // Do a relocation in which we convert a TLS Initial-Exec to a
2353 // Local-Exec.
2354
2355 inline void
2356 Target_x86_64::Relocate::tls_ie_to_le(const Relocate_info<64, false>* relinfo,
2357                                       size_t relnum,
2358                                       Output_segment* tls_segment,
2359                                       const elfcpp::Rela<64, false>& rela,
2360                                       unsigned int,
2361                                       elfcpp::Elf_types<64>::Elf_Addr value,
2362                                       unsigned char* view,
2363                                       section_size_type view_size)
2364 {
2365   // We need to examine the opcodes to figure out which instruction we
2366   // are looking at.
2367
2368   // movq foo@gottpoff(%rip),%reg  ==>  movq $YY,%reg
2369   // addq foo@gottpoff(%rip),%reg  ==>  addq $YY,%reg
2370
2371   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -3);
2372   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 4);
2373
2374   unsigned char op1 = view[-3];
2375   unsigned char op2 = view[-2];
2376   unsigned char op3 = view[-1];
2377   unsigned char reg = op3 >> 3;
2378
2379   if (op2 == 0x8b)
2380     {
2381       // movq
2382       if (op1 == 0x4c)
2383         view[-3] = 0x49;
2384       view[-2] = 0xc7;
2385       view[-1] = 0xc0 | reg;
2386     }
2387   else if (reg == 4)
2388     {
2389       // Special handling for %rsp.
2390       if (op1 == 0x4c)
2391         view[-3] = 0x49;
2392       view[-2] = 0x81;
2393       view[-1] = 0xc0 | reg;
2394     }
2395   else
2396     {
2397       // addq
2398       if (op1 == 0x4c)
2399         view[-3] = 0x4d;
2400       view[-2] = 0x8d;
2401       view[-1] = 0x80 | reg | (reg << 3);
2402     }
2403
2404   value -= tls_segment->memsz();
2405   Relocate_functions<64, false>::rela32(view, value, 0);
2406 }
2407
2408 // Relocate section data.
2409
2410 void
2411 Target_x86_64::relocate_section(const Relocate_info<64, false>* relinfo,
2412                                 unsigned int sh_type,
2413                                 const unsigned char* prelocs,
2414                                 size_t reloc_count,
2415                                 Output_section* output_section,
2416                                 bool needs_special_offset_handling,
2417                                 unsigned char* view,
2418                                 elfcpp::Elf_types<64>::Elf_Addr address,
2419                                 section_size_type view_size)
2420 {
2421   gold_assert(sh_type == elfcpp::SHT_RELA);
2422
2423   gold::relocate_section<64, false, Target_x86_64, elfcpp::SHT_RELA,
2424                          Target_x86_64::Relocate>(
2425     relinfo,
2426     this,
2427     prelocs,
2428     reloc_count,
2429     output_section,
2430     needs_special_offset_handling,
2431     view,
2432     address,
2433     view_size);
2434 }
2435
2436 // Return the size of a relocation while scanning during a relocatable
2437 // link.
2438
2439 unsigned int
2440 Target_x86_64::Relocatable_size_for_reloc::get_size_for_reloc(
2441     unsigned int r_type,
2442     Relobj* object)
2443 {
2444   switch (r_type)
2445     {
2446     case elfcpp::R_X86_64_NONE:
2447     case elfcpp::R_386_GNU_VTINHERIT:
2448     case elfcpp::R_386_GNU_VTENTRY:
2449     case elfcpp::R_X86_64_TLSGD:            // Global-dynamic
2450     case elfcpp::R_X86_64_GOTPC32_TLSDESC:  // Global-dynamic (from ~oliva url)
2451     case elfcpp::R_X86_64_TLSDESC_CALL:
2452     case elfcpp::R_X86_64_TLSLD:            // Local-dynamic
2453     case elfcpp::R_X86_64_DTPOFF32:
2454     case elfcpp::R_X86_64_DTPOFF64:
2455     case elfcpp::R_X86_64_GOTTPOFF:         // Initial-exec
2456     case elfcpp::R_X86_64_TPOFF32:          // Local-exec
2457       return 0;
2458
2459     case elfcpp::R_X86_64_64:
2460     case elfcpp::R_X86_64_PC64:
2461     case elfcpp::R_X86_64_GOTOFF64:
2462     case elfcpp::R_X86_64_GOTPC64:
2463     case elfcpp::R_X86_64_PLTOFF64:
2464     case elfcpp::R_X86_64_GOT64:
2465     case elfcpp::R_X86_64_GOTPCREL64:
2466     case elfcpp::R_X86_64_GOTPCREL:
2467     case elfcpp::R_X86_64_GOTPLT64:
2468       return 8;
2469
2470     case elfcpp::R_X86_64_32:
2471     case elfcpp::R_X86_64_32S:
2472     case elfcpp::R_X86_64_PC32:
2473     case elfcpp::R_X86_64_PLT32:
2474     case elfcpp::R_X86_64_GOTPC32:
2475     case elfcpp::R_X86_64_GOT32:
2476       return 4;
2477
2478     case elfcpp::R_X86_64_16:
2479     case elfcpp::R_X86_64_PC16:
2480       return 2;
2481
2482     case elfcpp::R_X86_64_8:
2483     case elfcpp::R_X86_64_PC8:
2484       return 1;
2485
2486     case elfcpp::R_X86_64_COPY:
2487     case elfcpp::R_X86_64_GLOB_DAT:
2488     case elfcpp::R_X86_64_JUMP_SLOT:
2489     case elfcpp::R_X86_64_RELATIVE:
2490       // These are outstanding tls relocs, which are unexpected when linking
2491     case elfcpp::R_X86_64_TPOFF64:
2492     case elfcpp::R_X86_64_DTPMOD64:
2493     case elfcpp::R_X86_64_TLSDESC:
2494       object->error(_("unexpected reloc %u in object file"), r_type);
2495       return 0;
2496
2497     case elfcpp::R_X86_64_SIZE32:
2498     case elfcpp::R_X86_64_SIZE64:
2499     default:
2500       object->error(_("unsupported reloc %u against local symbol"), r_type);
2501       return 0;
2502     }
2503 }
2504
2505 // Scan the relocs during a relocatable link.
2506
2507 void
2508 Target_x86_64::scan_relocatable_relocs(const General_options& options,
2509                                        Symbol_table* symtab,
2510                                        Layout* layout,
2511                                        Sized_relobj<64, false>* object,
2512                                        unsigned int data_shndx,
2513                                        unsigned int sh_type,
2514                                        const unsigned char* prelocs,
2515                                        size_t reloc_count,
2516                                        Output_section* output_section,
2517                                        bool needs_special_offset_handling,
2518                                        size_t local_symbol_count,
2519                                        const unsigned char* plocal_symbols,
2520                                        Relocatable_relocs* rr)
2521 {
2522   gold_assert(sh_type == elfcpp::SHT_RELA);
2523
2524   typedef gold::Default_scan_relocatable_relocs<elfcpp::SHT_RELA,
2525     Relocatable_size_for_reloc> Scan_relocatable_relocs;
2526
2527   gold::scan_relocatable_relocs<64, false, elfcpp::SHT_RELA,
2528       Scan_relocatable_relocs>(
2529     options,
2530     symtab,
2531     layout,
2532     object,
2533     data_shndx,
2534     prelocs,
2535     reloc_count,
2536     output_section,
2537     needs_special_offset_handling,
2538     local_symbol_count,
2539     plocal_symbols,
2540     rr);
2541 }
2542
2543 // Relocate a section during a relocatable link.
2544
2545 void
2546 Target_x86_64::relocate_for_relocatable(
2547     const Relocate_info<64, false>* relinfo,
2548     unsigned int sh_type,
2549     const unsigned char* prelocs,
2550     size_t reloc_count,
2551     Output_section* output_section,
2552     off_t offset_in_output_section,
2553     const Relocatable_relocs* rr,
2554     unsigned char* view,
2555     elfcpp::Elf_types<64>::Elf_Addr view_address,
2556     section_size_type view_size,
2557     unsigned char* reloc_view,
2558     section_size_type reloc_view_size)
2559 {
2560   gold_assert(sh_type == elfcpp::SHT_RELA);
2561
2562   gold::relocate_for_relocatable<64, false, elfcpp::SHT_RELA>(
2563     relinfo,
2564     prelocs,
2565     reloc_count,
2566     output_section,
2567     offset_in_output_section,
2568     rr,
2569     view,
2570     view_address,
2571     view_size,
2572     reloc_view,
2573     reloc_view_size);
2574 }
2575
2576 // Return the value to use for a dynamic which requires special
2577 // treatment.  This is how we support equality comparisons of function
2578 // pointers across shared library boundaries, as described in the
2579 // processor specific ABI supplement.
2580
2581 uint64_t
2582 Target_x86_64::do_dynsym_value(const Symbol* gsym) const
2583 {
2584   gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset());
2585   return this->plt_section()->address() + gsym->plt_offset();
2586 }
2587
2588 // Return a string used to fill a code section with nops to take up
2589 // the specified length.
2590
2591 std::string
2592 Target_x86_64::do_code_fill(section_size_type length) const
2593 {
2594   if (length >= 16)
2595     {
2596       // Build a jmpq instruction to skip over the bytes.
2597       unsigned char jmp[5];
2598       jmp[0] = 0xe9;
2599       elfcpp::Swap_unaligned<32, false>::writeval(jmp + 1, length - 5);
2600       return (std::string(reinterpret_cast<char*>(&jmp[0]), 5)
2601               + std::string(length - 5, '\0'));
2602     }
2603
2604   // Nop sequences of various lengths.
2605   const char nop1[1] = { 0x90 };                   // nop
2606   const char nop2[2] = { 0x66, 0x90 };             // xchg %ax %ax
2607   const char nop3[3] = { 0x8d, 0x76, 0x00 };       // leal 0(%esi),%esi
2608   const char nop4[4] = { 0x8d, 0x74, 0x26, 0x00};  // leal 0(%esi,1),%esi
2609   const char nop5[5] = { 0x90, 0x8d, 0x74, 0x26,   // nop
2610                          0x00 };                   // leal 0(%esi,1),%esi
2611   const char nop6[6] = { 0x8d, 0xb6, 0x00, 0x00,   // leal 0L(%esi),%esi
2612                          0x00, 0x00 };
2613   const char nop7[7] = { 0x8d, 0xb4, 0x26, 0x00,   // leal 0L(%esi,1),%esi
2614                          0x00, 0x00, 0x00 };
2615   const char nop8[8] = { 0x90, 0x8d, 0xb4, 0x26,   // nop
2616                          0x00, 0x00, 0x00, 0x00 }; // leal 0L(%esi,1),%esi
2617   const char nop9[9] = { 0x89, 0xf6, 0x8d, 0xbc,   // movl %esi,%esi
2618                          0x27, 0x00, 0x00, 0x00,   // leal 0L(%edi,1),%edi
2619                          0x00 };
2620   const char nop10[10] = { 0x8d, 0x76, 0x00, 0x8d, // leal 0(%esi),%esi
2621                            0xbc, 0x27, 0x00, 0x00, // leal 0L(%edi,1),%edi
2622                            0x00, 0x00 };
2623   const char nop11[11] = { 0x8d, 0x74, 0x26, 0x00, // leal 0(%esi,1),%esi
2624                            0x8d, 0xbc, 0x27, 0x00, // leal 0L(%edi,1),%edi
2625                            0x00, 0x00, 0x00 };
2626   const char nop12[12] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2627                            0x00, 0x00, 0x8d, 0xbf, // leal 0L(%edi),%edi
2628                            0x00, 0x00, 0x00, 0x00 };
2629   const char nop13[13] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2630                            0x00, 0x00, 0x8d, 0xbc, // leal 0L(%edi,1),%edi
2631                            0x27, 0x00, 0x00, 0x00,
2632                            0x00 };
2633   const char nop14[14] = { 0x8d, 0xb4, 0x26, 0x00, // leal 0L(%esi,1),%esi
2634                            0x00, 0x00, 0x00, 0x8d, // leal 0L(%edi,1),%edi
2635                            0xbc, 0x27, 0x00, 0x00,
2636                            0x00, 0x00 };
2637   const char nop15[15] = { 0xeb, 0x0d, 0x90, 0x90, // jmp .+15
2638                            0x90, 0x90, 0x90, 0x90, // nop,nop,nop,...
2639                            0x90, 0x90, 0x90, 0x90,
2640                            0x90, 0x90, 0x90 };
2641
2642   const char* nops[16] = {
2643     NULL,
2644     nop1, nop2, nop3, nop4, nop5, nop6, nop7,
2645     nop8, nop9, nop10, nop11, nop12, nop13, nop14, nop15
2646   };
2647
2648   return std::string(nops[length], length);
2649 }
2650
2651 // The selector for x86_64 object files.
2652
2653 class Target_selector_x86_64 : public Target_selector_freebsd
2654 {
2655 public:
2656   Target_selector_x86_64()
2657     : Target_selector_freebsd(elfcpp::EM_X86_64, 64, false, "elf64-x86-64",
2658                               "elf64-x86-64-freebsd")
2659   { }
2660
2661   Target*
2662   do_instantiate_target()
2663   { return new Target_x86_64(); }
2664
2665 };
2666
2667 Target_selector_x86_64 target_selector_x86_64;
2668
2669 } // End anonymous namespace.