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   // Hook for a new output section.
  71   void
  72   do_new_output_section(Output_section*) const;
  73
  74   // Scan the relocations to look for symbol adjustments.
  75   void
  76   gc_process_relocs(const General_options& options,
  77                     Symbol_table* symtab,
  78                     Layout* layout,
  79                     Sized_relobj<64, false>* object,
  80                     unsigned int data_shndx,
  81                     unsigned int sh_type,
  82                     const unsigned char* prelocs,
  83                     size_t reloc_count,
  84                     Output_section* output_section,
  85                     bool needs_special_offset_handling,
  86                     size_t local_symbol_count,
  87                     const unsigned char* plocal_symbols);
  88
  89   // Scan the relocations to look for symbol adjustments.
  90   void
  91   scan_relocs(const General_options& options,
  92               Symbol_table* symtab,
  93               Layout* layout,
  94               Sized_relobj<64, false>* object,
  95               unsigned int data_shndx,
  96               unsigned int sh_type,
  97               const unsigned char* prelocs,
  98               size_t reloc_count,
  99               Output_section* output_section,
 100               bool needs_special_offset_handling,
 101               size_t local_symbol_count,
 102               const unsigned char* plocal_symbols);
 103
 104   // Finalize the sections.
 105   void
 106   do_finalize_sections(Layout*);
 107
 108   // Return the value to use for a dynamic which requires special
 109   // treatment.
 110   uint64_t
 111   do_dynsym_value(const Symbol*) const;
 112
 113   // Relocate a section.
 114   void
 115   relocate_section(const Relocate_info<64, false>*,
 116                    unsigned int sh_type,
 117                    const unsigned char* prelocs,
 118                    size_t reloc_count,
 119                    Output_section* output_section,
 120                    bool needs_special_offset_handling,
 121                    unsigned char* view,
 122                    elfcpp::Elf_types<64>::Elf_Addr view_address,
 123                    section_size_type view_size);
 124
 125   // Scan the relocs during a relocatable link.
 126   void
 127   scan_relocatable_relocs(const General_options& options,
 128                           Symbol_table* symtab,
 129                           Layout* layout,
 130                           Sized_relobj<64, false>* object,
 131                           unsigned int data_shndx,
 132                           unsigned int sh_type,
 133                           const unsigned char* prelocs,
 134                           size_t reloc_count,
 135                           Output_section* output_section,
 136                           bool needs_special_offset_handling,
 137                           size_t local_symbol_count,
 138                           const unsigned char* plocal_symbols,
 139                           Relocatable_relocs*);
 140
 141   // Relocate a section during a relocatable link.
 142   void
 143   relocate_for_relocatable(const Relocate_info<64, false>*,
 144                            unsigned int sh_type,
 145                            const unsigned char* prelocs,
 146                            size_t reloc_count,
 147                            Output_section* output_section,
 148                            off_t offset_in_output_section,
 149                            const Relocatable_relocs*,
 150                            unsigned char* view,
 151                            elfcpp::Elf_types<64>::Elf_Addr view_address,
 152                            section_size_type view_size,
 153                            unsigned char* reloc_view,
 154                            section_size_type reloc_view_size);
 155
 156   // Return a string used to fill a code section with nops.
 157   std::string
 158   do_code_fill(section_size_type length) const;
 159
 160   // Return whether SYM is defined by the ABI.
 161   bool
 162   do_is_defined_by_abi(const Symbol* sym) const
 163   { return strcmp(sym->name(), "__tls_get_addr") == 0; }
 164
 165   // Return the size of the GOT section.
 166   section_size_type
 167   got_size()
 168   {
 169     gold_assert(this->got_ != NULL);
 170     return this->got_->data_size();
 171   }
 172
 173  private:
 174   // The class which scans relocations.
 175   class Scan
 176   {
 177   public:
 178     Scan()
 179       : issued_non_pic_error_(false)
 180     { }
 181
 182     inline void
 183     local(const General_options& options, Symbol_table* symtab,
 184           Layout* layout, Target_x86_64* target,
 185           Sized_relobj<64, false>* object,
 186           unsigned int data_shndx,
 187           Output_section* output_section,
 188           const elfcpp::Rela<64, false>& reloc, unsigned int r_type,
 189           const elfcpp::Sym<64, false>& lsym);
 190
 191     inline void
 192     global(const General_options& options, Symbol_table* symtab,
 193            Layout* layout, Target_x86_64* target,
 194            Sized_relobj<64, false>* object,
 195            unsigned int data_shndx,
 196            Output_section* output_section,
 197            const elfcpp::Rela<64, false>& reloc, unsigned int r_type,
 198            Symbol* gsym);
 199
 200   private:
 201     static void
 202     unsupported_reloc_local(Sized_relobj<64, false>*, unsigned int r_type);
 203
 204     static void
 205     unsupported_reloc_global(Sized_relobj<64, false>*, unsigned int r_type,
 206                              Symbol*);
 207
 208     void
 209     check_non_pic(Relobj*, unsigned int r_type);
 210
 211     // Whether we have issued an error about a non-PIC compilation.
 212     bool issued_non_pic_error_;
 213   };
 214
 215   // The class which implements relocation.
 216   class Relocate
 217   {
 218    public:
 219     Relocate()
 220       : skip_call_tls_get_addr_(false), saw_tls_block_reloc_(false)
 221     { }
 222
 223     ~Relocate()
 224     {
 225       if (this->skip_call_tls_get_addr_)
 226         {
 227           // FIXME: This needs to specify the location somehow.
 228           gold_error(_("missing expected TLS relocation"));
 229         }
 230     }
 231
 232     // Do a relocation.  Return false if the caller should not issue
 233     // any warnings about this relocation.
 234     inline bool
 235     relocate(const Relocate_info<64, false>*, Target_x86_64*, Output_section*,
 236              size_t relnum, const elfcpp::Rela<64, false>&,
 237              unsigned int r_type, const Sized_symbol<64>*,
 238              const Symbol_value<64>*,
 239              unsigned char*, elfcpp::Elf_types<64>::Elf_Addr,
 240              section_size_type);
 241
 242    private:
 243     // Do a TLS relocation.
 244     inline void
 245     relocate_tls(const Relocate_info<64, false>*, Target_x86_64*,
 246                  size_t relnum, const elfcpp::Rela<64, false>&,
 247                  unsigned int r_type, const Sized_symbol<64>*,
 248                  const Symbol_value<64>*,
 249                  unsigned char*, elfcpp::Elf_types<64>::Elf_Addr,
 250                  section_size_type);
 251
 252     // Do a TLS General-Dynamic to Initial-Exec transition.
 253     inline void
 254     tls_gd_to_ie(const Relocate_info<64, false>*, size_t relnum,
 255                  Output_segment* tls_segment,
 256                  const elfcpp::Rela<64, false>&, unsigned int r_type,
 257                  elfcpp::Elf_types<64>::Elf_Addr value,
 258                  unsigned char* view,
 259                  elfcpp::Elf_types<64>::Elf_Addr,
 260                  section_size_type view_size);
 261
 262     // Do a TLS General-Dynamic to Local-Exec transition.
 263     inline void
 264     tls_gd_to_le(const Relocate_info<64, false>*, size_t relnum,
 265                  Output_segment* tls_segment,
 266                  const elfcpp::Rela<64, false>&, unsigned int r_type,
 267                  elfcpp::Elf_types<64>::Elf_Addr value,
 268                  unsigned char* view,
 269                  section_size_type view_size);
 270
 271     // Do a TLSDESC-style General-Dynamic to Initial-Exec transition.
 272     inline void
 273     tls_desc_gd_to_ie(const Relocate_info<64, false>*, size_t relnum,
 274                       Output_segment* tls_segment,
 275                       const elfcpp::Rela<64, false>&, unsigned int r_type,
 276                       elfcpp::Elf_types<64>::Elf_Addr value,
 277                       unsigned char* view,
 278                       elfcpp::Elf_types<64>::Elf_Addr,
 279                       section_size_type view_size);
 280
 281     // Do a TLSDESC-style General-Dynamic to Local-Exec transition.
 282     inline void
 283     tls_desc_gd_to_le(const Relocate_info<64, false>*, size_t relnum,
 284                       Output_segment* tls_segment,
 285                       const elfcpp::Rela<64, false>&, unsigned int r_type,
 286                       elfcpp::Elf_types<64>::Elf_Addr value,
 287                       unsigned char* view,
 288                       section_size_type view_size);
 289
 290     // Do a TLS Local-Dynamic to Local-Exec transition.
 291     inline void
 292     tls_ld_to_le(const Relocate_info<64, false>*, size_t relnum,
 293                  Output_segment* tls_segment,
 294                  const elfcpp::Rela<64, false>&, unsigned int r_type,
 295                  elfcpp::Elf_types<64>::Elf_Addr value,
 296                  unsigned char* view,
 297                  section_size_type view_size);
 298
 299     // Do a TLS Initial-Exec to Local-Exec transition.
 300     static inline void
 301     tls_ie_to_le(const Relocate_info<64, false>*, size_t relnum,
 302                  Output_segment* tls_segment,
 303                  const elfcpp::Rela<64, false>&, unsigned int r_type,
 304                  elfcpp::Elf_types<64>::Elf_Addr value,
 305                  unsigned char* view,
 306                  section_size_type view_size);
 307
 308     // This is set if we should skip the next reloc, which should be a
 309     // PLT32 reloc against ___tls_get_addr.
 310     bool skip_call_tls_get_addr_;
 311
 312     // This is set if we see a relocation which could load the address
 313     // of the TLS block.  Whether we see such a relocation determines
 314     // how we handle the R_X86_64_DTPOFF32 relocation, which is used
 315     // in debugging sections.
 316     bool saw_tls_block_reloc_;
 317   };
 318
 319   // A class which returns the size required for a relocation type,
 320   // used while scanning relocs during a relocatable link.
 321   class Relocatable_size_for_reloc
 322   {
 323    public:
 324     unsigned int
 325     get_size_for_reloc(unsigned int, Relobj*);
 326   };
 327
 328   // Adjust TLS relocation type based on the options and whether this
 329   // is a local symbol.
 330   static tls::Tls_optimization
 331   optimize_tls_reloc(bool is_final, int r_type);
 332
 333   // Get the GOT section, creating it if necessary.
 334   Output_data_got<64, false>*
 335   got_section(Symbol_table*, Layout*);
 336
 337   // Get the GOT PLT section.
 338   Output_data_space*
 339   got_plt_section() const
 340   {
 341     gold_assert(this->got_plt_ != NULL);
 342     return this->got_plt_;
 343   }
 344
 345   // Create the PLT section.
 346   void
 347   make_plt_section(Symbol_table* symtab, Layout* layout);
 348
 349   // Create a PLT entry for a global symbol.
 350   void
 351   make_plt_entry(Symbol_table*, Layout*, Symbol*);
 352
 353   // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
 354   void
 355   define_tls_base_symbol(Symbol_table*, Layout*);
 356
 357   // Create the reserved PLT and GOT entries for the TLS descriptor resolver.
 358   void
 359   reserve_tlsdesc_entries(Symbol_table* symtab, Layout* layout);
 360
 361   // Create a GOT entry for the TLS module index.
 362   unsigned int
 363   got_mod_index_entry(Symbol_table* symtab, Layout* layout,
 364                       Sized_relobj<64, false>* object);
 365
 366   // Get the PLT section.
 367   Output_data_plt_x86_64*
 368   plt_section() const
 369   {
 370     gold_assert(this->plt_ != NULL);
 371     return this->plt_;
 372   }
 373
 374   // Get the dynamic reloc section, creating it if necessary.
 375   Reloc_section*
 376   rela_dyn_section(Layout*);
 377
 378   // Add a potential copy relocation.
 379   void
 380   copy_reloc(Symbol_table* symtab, Layout* layout,
 381              Sized_relobj<64, false>* object,
 382              unsigned int shndx, Output_section* output_section,
 383              Symbol* sym, const elfcpp::Rela<64, false>& reloc)
 384   {
 385     this->copy_relocs_.copy_reloc(symtab, layout,
 386                                   symtab->get_sized_symbol<64>(sym),
 387                                   object, shndx, output_section,
 388                                   reloc, this->rela_dyn_section(layout));
 389   }
 390
 391   // Information about this specific target which we pass to the
 392   // general Target structure.
 393   static const Target::Target_info x86_64_info;
 394
 395   enum Got_type
 396   {
 397     GOT_TYPE_STANDARD = 0,      // GOT entry for a regular symbol
 398     GOT_TYPE_TLS_OFFSET = 1,    // GOT entry for TLS offset
 399     GOT_TYPE_TLS_PAIR = 2,      // GOT entry for TLS module/offset pair
 400     GOT_TYPE_TLS_DESC = 3       // GOT entry for TLS_DESC pair
 401   };
 402
 403   // The GOT section.
 404   Output_data_got<64, false>* got_;
 405   // The PLT section.
 406   Output_data_plt_x86_64* plt_;
 407   // The GOT PLT section.
 408   Output_data_space* got_plt_;
 409   // The dynamic reloc section.
 410   Reloc_section* rela_dyn_;
 411   // Relocs saved to avoid a COPY reloc.
 412   Copy_relocs<elfcpp::SHT_RELA, 64, false> copy_relocs_;
 413   // Space for variables copied with a COPY reloc.
 414   Output_data_space* dynbss_;
 415   // Offset of the GOT entry for the TLS module index.
 416   unsigned int got_mod_index_offset_;
 417   // True if the _TLS_MODULE_BASE_ symbol has been defined.
 418   bool tls_base_symbol_defined_;
 419 };
 420
 421 const Target::Target_info Target_x86_64::x86_64_info =
 422 {
 423   64,                   // size
 424   false,                // is_big_endian
 425   elfcpp::EM_X86_64,    // machine_code
 426   false,                // has_make_symbol
 427   false,                // has_resolve
 428   true,                 // has_code_fill
 429   true,                 // is_default_stack_executable
 430   '\0',                 // wrap_char
 431   "/lib/ld64.so.1",     // program interpreter
 432   0x400000,             // default_text_segment_address
 433   0x1000,               // abi_pagesize (overridable by -z max-page-size)
 434   0x1000,               // common_pagesize (overridable by -z common-page-size)
 435   elfcpp::SHN_UNDEF,    // small_common_shndx
 436   elfcpp::SHN_X86_64_LCOMMON,   // large_common_shndx
 437   0,                    // small_common_section_flags
 438   elfcpp::SHF_X86_64_LARGE      // large_common_section_flags
 439 };
 440
 441 // This is called when a new output section is created.  This is where
 442 // we handle the SHF_X86_64_LARGE.
 443
 444 void
 445 Target_x86_64::do_new_output_section(Output_section *os) const
 446 {
 447   if ((os->flags() & elfcpp::SHF_X86_64_LARGE) != 0)
 448     os->set_is_large_section();
 449 }
 450
 451 // Get the GOT section, creating it if necessary.
 452
 453 Output_data_got<64, false>*
 454 Target_x86_64::got_section(Symbol_table* symtab, Layout* layout)
 455 {
 456   if (this->got_ == NULL)
 457     {
 458       gold_assert(symtab != NULL && layout != NULL);
 459
 460       this->got_ = new Output_data_got<64, false>();
 461
 462       Output_section* os;
 463       os = layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
 464                                            (elfcpp::SHF_ALLOC
 465                                             | elfcpp::SHF_WRITE),
 466                                            this->got_);
 467       os->set_is_relro();
 468
 469       // The old GNU linker creates a .got.plt section.  We just
 470       // create another set of data in the .got section.  Note that we
 471       // always create a PLT if we create a GOT, although the PLT
 472       // might be empty.
 473       this->got_plt_ = new Output_data_space(8, "** GOT PLT");
 474       os = layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
 475                                            (elfcpp::SHF_ALLOC
 476                                             | elfcpp::SHF_WRITE),
 477                                            this->got_plt_);
 478       os->set_is_relro();
 479
 480       // The first three entries are reserved.
 481       this->got_plt_->set_current_data_size(3 * 8);
 482
 483       // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
 484       symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
 485                                     this->got_plt_,
 486                                     0, 0, elfcpp::STT_OBJECT,
 487                                     elfcpp::STB_LOCAL,
 488                                     elfcpp::STV_HIDDEN, 0,
 489                                     false, false);
 490     }
 491
 492   return this->got_;
 493 }
 494
 495 // Get the dynamic reloc section, creating it if necessary.
 496
 497 Target_x86_64::Reloc_section*
 498 Target_x86_64::rela_dyn_section(Layout* layout)
 499 {
 500   if (this->rela_dyn_ == NULL)
 501     {
 502       gold_assert(layout != NULL);
 503       this->rela_dyn_ = new Reloc_section(parameters->options().combreloc());
 504       layout->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA,
 505                                       elfcpp::SHF_ALLOC, this->rela_dyn_);
 506     }
 507   return this->rela_dyn_;
 508 }
 509
 510 // A class to handle the PLT data.
 511
 512 class Output_data_plt_x86_64 : public Output_section_data
 513 {
 514  public:
 515   typedef Output_data_reloc<elfcpp::SHT_RELA, true, 64, false> Reloc_section;
 516
 517   Output_data_plt_x86_64(Layout*, Output_data_got<64, false>*,
 518                          Output_data_space*);
 519
 520   // Add an entry to the PLT.
 521   void
 522   add_entry(Symbol* gsym);
 523
 524   // Add the reserved TLSDESC_PLT entry to the PLT.
 525   void
 526   reserve_tlsdesc_entry(unsigned int got_offset)
 527   { this->tlsdesc_got_offset_ = got_offset; }
 528
 529   // Return true if a TLSDESC_PLT entry has been reserved.
 530   bool
 531   has_tlsdesc_entry() const
 532   { return this->tlsdesc_got_offset_ != -1U; }
 533
 534   // Return the GOT offset for the reserved TLSDESC_PLT entry.
 535   unsigned int
 536   get_tlsdesc_got_offset() const
 537   { return this->tlsdesc_got_offset_; }
 538
 539   // Return the offset of the reserved TLSDESC_PLT entry.
 540   unsigned int
 541   get_tlsdesc_plt_offset() const
 542   { return (this->count_ + 1) * plt_entry_size; }
 543
 544   // Return the .rel.plt section data.
 545   const Reloc_section*
 546   rel_plt() const
 547   { return this->rel_; }
 548
 549  protected:
 550   void
 551   do_adjust_output_section(Output_section* os);
 552
 553   // Write to a map file.
 554   void
 555   do_print_to_mapfile(Mapfile* mapfile) const
 556   { mapfile->print_output_data(this, _("** PLT")); }
 557
 558  private:
 559   // The size of an entry in the PLT.
 560   static const int plt_entry_size = 16;
 561
 562   // The first entry in the PLT.
 563   // From the AMD64 ABI: "Unlike Intel386 ABI, this ABI uses the same
 564   // procedure linkage table for both programs and shared objects."
 565   static unsigned char first_plt_entry[plt_entry_size];
 566
 567   // Other entries in the PLT for an executable.
 568   static unsigned char plt_entry[plt_entry_size];
 569
 570   // The reserved TLSDESC entry in the PLT for an executable.
 571   static unsigned char tlsdesc_plt_entry[plt_entry_size];
 572
 573   // Set the final size.
 574   void
 575   set_final_data_size();
 576
 577   // Write out the PLT data.
 578   void
 579   do_write(Output_file*);
 580
 581   // The reloc section.
 582   Reloc_section* rel_;
 583   // The .got section.
 584   Output_data_got<64, false>* got_;
 585   // The .got.plt section.
 586   Output_data_space* got_plt_;
 587   // The number of PLT entries.
 588   unsigned int count_;
 589   // Offset of the reserved TLSDESC_GOT entry when needed.
 590   unsigned int tlsdesc_got_offset_;
 591 };
 592
 593 // Create the PLT section.  The ordinary .got section is an argument,
 594 // since we need to refer to the start.  We also create our own .got
 595 // section just for PLT entries.
 596
 597 Output_data_plt_x86_64::Output_data_plt_x86_64(Layout* layout,
 598                                                Output_data_got<64, false>* got,
 599                                                Output_data_space* got_plt)
 600   : Output_section_data(8), got_(got), got_plt_(got_plt), count_(0),
 601     tlsdesc_got_offset_(-1U)
 602 {
 603   this->rel_ = new Reloc_section(false);
 604   layout->add_output_section_data(".rela.plt", elfcpp::SHT_RELA,
 605                                   elfcpp::SHF_ALLOC, this->rel_);
 606 }
 607
 608 void
 609 Output_data_plt_x86_64::do_adjust_output_section(Output_section* os)
 610 {
 611   os->set_entsize(plt_entry_size);
 612 }
 613
 614 // Add an entry to the PLT.
 615
 616 void
 617 Output_data_plt_x86_64::add_entry(Symbol* gsym)
 618 {
 619   gold_assert(!gsym->has_plt_offset());
 620
 621   // Note that when setting the PLT offset we skip the initial
 622   // reserved PLT entry.
 623   gsym->set_plt_offset((this->count_ + 1) * plt_entry_size);
 624
 625   ++this->count_;
 626
 627   section_offset_type got_offset = this->got_plt_->current_data_size();
 628
 629   // Every PLT entry needs a GOT entry which points back to the PLT
 630   // entry (this will be changed by the dynamic linker, normally
 631   // lazily when the function is called).
 632   this->got_plt_->set_current_data_size(got_offset + 8);
 633
 634   // Every PLT entry needs a reloc.
 635   gsym->set_needs_dynsym_entry();
 636   this->rel_->add_global(gsym, elfcpp::R_X86_64_JUMP_SLOT, this->got_plt_,
 637                          got_offset, 0);
 638
 639   // Note that we don't need to save the symbol.  The contents of the
 640   // PLT are independent of which symbols are used.  The symbols only
 641   // appear in the relocations.
 642 }
 643
 644 // Set the final size.
 645 void
 646 Output_data_plt_x86_64::set_final_data_size()
 647 {
 648   unsigned int count = this->count_;
 649   if (this->has_tlsdesc_entry())
 650     ++count;
 651   this->set_data_size((count + 1) * plt_entry_size);
 652 }
 653
 654 // The first entry in the PLT for an executable.
 655
 656 unsigned char Output_data_plt_x86_64::first_plt_entry[plt_entry_size] =
 657 {
 658   // From AMD64 ABI Draft 0.98, page 76
 659   0xff, 0x35,   // pushq contents of memory address
 660   0, 0, 0, 0,   // replaced with address of .got + 8
 661   0xff, 0x25,   // jmp indirect
 662   0, 0, 0, 0,   // replaced with address of .got + 16
 663   0x90, 0x90, 0x90, 0x90   // noop (x4)
 664 };
 665
 666 // Subsequent entries in the PLT for an executable.
 667
 668 unsigned char Output_data_plt_x86_64::plt_entry[plt_entry_size] =
 669 {
 670   // From AMD64 ABI Draft 0.98, page 76
 671   0xff, 0x25,   // jmpq indirect
 672   0, 0, 0, 0,   // replaced with address of symbol in .got
 673   0x68,         // pushq immediate
 674   0, 0, 0, 0,   // replaced with offset into relocation table
 675   0xe9,         // jmpq relative
 676   0, 0, 0, 0    // replaced with offset to start of .plt
 677 };
 678
 679 // The reserved TLSDESC entry in the PLT for an executable.
 680
 681 unsigned char Output_data_plt_x86_64::tlsdesc_plt_entry[plt_entry_size] =
 682 {
 683   // From Alexandre Oliva, "Thread-Local Storage Descriptors for IA32
 684   // and AMD64/EM64T", Version 0.9.4 (2005-10-10).
 685   0xff, 0x35,   // pushq x(%rip)
 686   0, 0, 0, 0,   // replaced with address of linkmap GOT entry (at PLTGOT + 8)
 687   0xff, 0x25,   // jmpq *y(%rip)
 688   0, 0, 0, 0,   // replaced with offset of reserved TLSDESC_GOT entry
 689   0x0f, 0x1f,   // nop
 690   0x40, 0
 691 };
 692
 693 // Write out the PLT.  This uses the hand-coded instructions above,
 694 // and adjusts them as needed.  This is specified by the AMD64 ABI.
 695
 696 void
 697 Output_data_plt_x86_64::do_write(Output_file* of)
 698 {
 699   const off_t offset = this->offset();
 700   const section_size_type oview_size =
 701     convert_to_section_size_type(this->data_size());
 702   unsigned char* const oview = of->get_output_view(offset, oview_size);
 703
 704   const off_t got_file_offset = this->got_plt_->offset();
 705   const section_size_type got_size =
 706     convert_to_section_size_type(this->got_plt_->data_size());
 707   unsigned char* const got_view = of->get_output_view(got_file_offset,
 708                                                       got_size);
 709
 710   unsigned char* pov = oview;
 711
 712   // The base address of the .plt section.
 713   elfcpp::Elf_types<64>::Elf_Addr plt_address = this->address();
 714   // The base address of the .got section.
 715   elfcpp::Elf_types<64>::Elf_Addr got_base = this->got_->address();
 716   // The base address of the PLT portion of the .got section,
 717   // which is where the GOT pointer will point, and where the
 718   // three reserved GOT entries are located.
 719   elfcpp::Elf_types<64>::Elf_Addr got_address = this->got_plt_->address();
 720
 721   memcpy(pov, first_plt_entry, plt_entry_size);
 722   // We do a jmp relative to the PC at the end of this instruction.
 723   elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
 724                                               (got_address + 8
 725                                                - (plt_address + 6)));
 726   elfcpp::Swap<32, false>::writeval(pov + 8,
 727                                     (got_address + 16
 728                                      - (plt_address + 12)));
 729   pov += plt_entry_size;
 730
 731   unsigned char* got_pov = got_view;
 732
 733   memset(got_pov, 0, 24);
 734   got_pov += 24;
 735
 736   unsigned int plt_offset = plt_entry_size;
 737   unsigned int got_offset = 24;
 738   const unsigned int count = this->count_;
 739   for (unsigned int plt_index = 0;
 740        plt_index < count;
 741        ++plt_index,
 742          pov += plt_entry_size,
 743          got_pov += 8,
 744          plt_offset += plt_entry_size,
 745          got_offset += 8)
 746     {
 747       // Set and adjust the PLT entry itself.
 748       memcpy(pov, plt_entry, plt_entry_size);
 749       elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
 750                                                   (got_address + got_offset
 751                                                    - (plt_address + plt_offset
 752                                                       + 6)));
 753
 754       elfcpp::Swap_unaligned<32, false>::writeval(pov + 7, plt_index);
 755       elfcpp::Swap<32, false>::writeval(pov + 12,
 756                                         - (plt_offset + plt_entry_size));
 757
 758       // Set the entry in the GOT.
 759       elfcpp::Swap<64, false>::writeval(got_pov, plt_address + plt_offset + 6);
 760     }
 761
 762   if (this->has_tlsdesc_entry())
 763     {
 764       // Set and adjust the reserved TLSDESC PLT entry.
 765       unsigned int tlsdesc_got_offset = this->get_tlsdesc_got_offset();
 766       memcpy(pov, tlsdesc_plt_entry, plt_entry_size);
 767       elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
 768                                                   (got_address + 8
 769                                                    - (plt_address + plt_offset
 770                                                       + 6)));
 771       elfcpp::Swap_unaligned<32, false>::writeval(pov + 8,
 772                                                   (got_base
 773                                                    + tlsdesc_got_offset
 774                                                    - (plt_address + plt_offset
 775                                                       + 12)));
 776       pov += plt_entry_size;
 777     }
 778
 779   gold_assert(static_cast<section_size_type>(pov - oview) == oview_size);
 780   gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size);
 781
 782   of->write_output_view(offset, oview_size, oview);
 783   of->write_output_view(got_file_offset, got_size, got_view);
 784 }
 785
 786 // Create the PLT section.
 787
 788 void
 789 Target_x86_64::make_plt_section(Symbol_table* symtab, Layout* layout)
 790 {
 791   if (this->plt_ == NULL)
 792     {
 793       // Create the GOT sections first.
 794       this->got_section(symtab, layout);
 795
 796       this->plt_ = new Output_data_plt_x86_64(layout, this->got_,
 797                                               this->got_plt_);
 798       layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
 799                                       (elfcpp::SHF_ALLOC
 800                                        | elfcpp::SHF_EXECINSTR),
 801                                       this->plt_);
 802     }
 803 }
 804
 805 // Create a PLT entry for a global symbol.
 806
 807 void
 808 Target_x86_64::make_plt_entry(Symbol_table* symtab, Layout* layout,
 809                               Symbol* gsym)
 810 {
 811   if (gsym->has_plt_offset())
 812     return;
 813
 814   if (this->plt_ == NULL)
 815     this->make_plt_section(symtab, layout);
 816
 817   this->plt_->add_entry(gsym);
 818 }
 819
 820 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
 821
 822 void
 823 Target_x86_64::define_tls_base_symbol(Symbol_table* symtab, Layout* layout)
 824 {
 825   if (this->tls_base_symbol_defined_)
 826     return;
 827
 828   Output_segment* tls_segment = layout->tls_segment();
 829   if (tls_segment != NULL)
 830     {
 831       bool is_exec = parameters->options().output_is_executable();
 832       symtab->define_in_output_segment("_TLS_MODULE_BASE_", NULL,
 833                                        tls_segment, 0, 0,
 834                                        elfcpp::STT_TLS,
 835                                        elfcpp::STB_LOCAL,
 836                                        elfcpp::STV_HIDDEN, 0,
 837                                        (is_exec
 838                                         ? Symbol::SEGMENT_END
 839                                         : Symbol::SEGMENT_START),
 840                                        true);
 841     }
 842   this->tls_base_symbol_defined_ = true;
 843 }
 844
 845 // Create the reserved PLT and GOT entries for the TLS descriptor resolver.
 846
 847 void
 848 Target_x86_64::reserve_tlsdesc_entries(Symbol_table* symtab,
 849                                              Layout* layout)
 850 {
 851   if (this->plt_ == NULL)
 852     this->make_plt_section(symtab, layout);
 853
 854   if (!this->plt_->has_tlsdesc_entry())
 855     {
 856       // Allocate the TLSDESC_GOT entry.
 857       Output_data_got<64, false>* got = this->got_section(symtab, layout);
 858       unsigned int got_offset = got->add_constant(0);
 859
 860       // Allocate the TLSDESC_PLT entry.
 861       this->plt_->reserve_tlsdesc_entry(got_offset);
 862     }
 863 }
 864
 865 // Create a GOT entry for the TLS module index.
 866
 867 unsigned int
 868 Target_x86_64::got_mod_index_entry(Symbol_table* symtab, Layout* layout,
 869                                    Sized_relobj<64, false>* object)
 870 {
 871   if (this->got_mod_index_offset_ == -1U)
 872     {
 873       gold_assert(symtab != NULL && layout != NULL && object != NULL);
 874       Reloc_section* rela_dyn = this->rela_dyn_section(layout);
 875       Output_data_got<64, false>* got = this->got_section(symtab, layout);
 876       unsigned int got_offset = got->add_constant(0);
 877       rela_dyn->add_local(object, 0, elfcpp::R_X86_64_DTPMOD64, got,
 878                           got_offset, 0);
 879       got->add_constant(0);
 880       this->got_mod_index_offset_ = got_offset;
 881     }
 882   return this->got_mod_index_offset_;
 883 }
 884
 885 // Optimize the TLS relocation type based on what we know about the
 886 // symbol.  IS_FINAL is true if the final address of this symbol is
 887 // known at link time.
 888
 889 tls::Tls_optimization
 890 Target_x86_64::optimize_tls_reloc(bool is_final, int r_type)
 891 {
 892   // If we are generating a shared library, then we can't do anything
 893   // in the linker.
 894   if (parameters->options().shared())
 895     return tls::TLSOPT_NONE;
 896
 897   switch (r_type)
 898     {
 899     case elfcpp::R_X86_64_TLSGD:
 900     case elfcpp::R_X86_64_GOTPC32_TLSDESC:
 901     case elfcpp::R_X86_64_TLSDESC_CALL:
 902       // These are General-Dynamic which permits fully general TLS
 903       // access.  Since we know that we are generating an executable,
 904       // we can convert this to Initial-Exec.  If we also know that
 905       // this is a local symbol, we can further switch to Local-Exec.
 906       if (is_final)
 907         return tls::TLSOPT_TO_LE;
 908       return tls::TLSOPT_TO_IE;
 909
 910     case elfcpp::R_X86_64_TLSLD:
 911       // This is Local-Dynamic, which refers to a local symbol in the
 912       // dynamic TLS block.  Since we know that we generating an
 913       // executable, we can switch to Local-Exec.
 914       return tls::TLSOPT_TO_LE;
 915
 916     case elfcpp::R_X86_64_DTPOFF32:
 917     case elfcpp::R_X86_64_DTPOFF64:
 918       // Another Local-Dynamic reloc.
 919       return tls::TLSOPT_TO_LE;
 920
 921     case elfcpp::R_X86_64_GOTTPOFF:
 922       // These are Initial-Exec relocs which get the thread offset
 923       // from the GOT.  If we know that we are linking against the
 924       // local symbol, we can switch to Local-Exec, which links the
 925       // thread offset into the instruction.
 926       if (is_final)
 927         return tls::TLSOPT_TO_LE;
 928       return tls::TLSOPT_NONE;
 929
 930     case elfcpp::R_X86_64_TPOFF32:
 931       // When we already have Local-Exec, there is nothing further we
 932       // can do.
 933       return tls::TLSOPT_NONE;
 934
 935     default:
 936       gold_unreachable();
 937     }
 938 }
 939
 940 // Report an unsupported relocation against a local symbol.
 941
 942 void
 943 Target_x86_64::Scan::unsupported_reloc_local(Sized_relobj<64, false>* object,
 944                                              unsigned int r_type)
 945 {
 946   gold_error(_("%s: unsupported reloc %u against local symbol"),
 947              object->name().c_str(), r_type);
 948 }
 949
 950 // We are about to emit a dynamic relocation of type R_TYPE.  If the
 951 // dynamic linker does not support it, issue an error.  The GNU linker
 952 // only issues a non-PIC error for an allocated read-only section.
 953 // Here we know the section is allocated, but we don't know that it is
 954 // read-only.  But we check for all the relocation types which the
 955 // glibc dynamic linker supports, so it seems appropriate to issue an
 956 // error even if the section is not read-only.
 957
 958 void
 959 Target_x86_64::Scan::check_non_pic(Relobj* object, unsigned int r_type)
 960 {
 961   switch (r_type)
 962     {
 963       // These are the relocation types supported by glibc for x86_64.
 964     case elfcpp::R_X86_64_RELATIVE:
 965     case elfcpp::R_X86_64_GLOB_DAT:
 966     case elfcpp::R_X86_64_JUMP_SLOT:
 967     case elfcpp::R_X86_64_DTPMOD64:
 968     case elfcpp::R_X86_64_DTPOFF64:
 969     case elfcpp::R_X86_64_TPOFF64:
 970     case elfcpp::R_X86_64_64:
 971     case elfcpp::R_X86_64_32:
 972     case elfcpp::R_X86_64_PC32:
 973     case elfcpp::R_X86_64_COPY:
 974       return;
 975
 976     default:
 977       // This prevents us from issuing more than one error per reloc
 978       // section.  But we can still wind up issuing more than one
 979       // error per object file.
 980       if (this->issued_non_pic_error_)
 981         return;
 982       gold_assert(parameters->options().output_is_position_independent());
 983       object->error(_("requires unsupported dynamic reloc; "
 984                       "recompile with -fPIC"));
 985       this->issued_non_pic_error_ = true;
 986       return;
 987
 988     case elfcpp::R_X86_64_NONE:
 989       gold_unreachable();
 990     }
 991 }
 992
 993 // Scan a relocation for a local symbol.
 994
 995 inline void
 996 Target_x86_64::Scan::local(const General_options&,
 997                            Symbol_table* symtab,
 998                            Layout* layout,
 999                            Target_x86_64* target,
1000                            Sized_relobj<64, false>* object,
1001                            unsigned int data_shndx,
1002                            Output_section* output_section,
1003                            const elfcpp::Rela<64, false>& reloc,
1004                            unsigned int r_type,
1005                            const elfcpp::Sym<64, false>& lsym)
1006 {
1007   switch (r_type)
1008     {
1009     case elfcpp::R_X86_64_NONE:
1010     case elfcpp::R_386_GNU_VTINHERIT:
1011     case elfcpp::R_386_GNU_VTENTRY:
1012       break;
1013
1014     case elfcpp::R_X86_64_64:
1015       // If building a shared library (or a position-independent
1016       // executable), we need to create a dynamic relocation for this
1017       // location.  The relocation applied at link time will apply the
1018       // link-time value, so we flag the location with an
1019       // R_X86_64_RELATIVE relocation so the dynamic loader can
1020       // relocate it easily.
1021       if (parameters->options().output_is_position_independent())
1022         {
1023           unsigned int r_sym = elfcpp::elf_r_sym<64>(reloc.get_r_info());
1024           Reloc_section* rela_dyn = target->rela_dyn_section(layout);
1025           rela_dyn->add_local_relative(object, r_sym,
1026                                        elfcpp::R_X86_64_RELATIVE,
1027                                        output_section, data_shndx,
1028                                        reloc.get_r_offset(),
1029                                        reloc.get_r_addend());
1030         }
1031       break;
1032
1033     case elfcpp::R_X86_64_32:
1034     case elfcpp::R_X86_64_32S:
1035     case elfcpp::R_X86_64_16:
1036     case elfcpp::R_X86_64_8:
1037       // If building a shared library (or a position-independent
1038       // executable), we need to create a dynamic relocation for this
1039       // location.  We can't use an R_X86_64_RELATIVE relocation
1040       // because that is always a 64-bit relocation.
1041       if (parameters->options().output_is_position_independent())
1042         {
1043           this->check_non_pic(object, r_type);
1044
1045           Reloc_section* rela_dyn = target->rela_dyn_section(layout);
1046           unsigned int r_sym = elfcpp::elf_r_sym<64>(reloc.get_r_info());
1047           if (lsym.get_st_type() != elfcpp::STT_SECTION)
1048             rela_dyn->add_local(object, r_sym, r_type, output_section,
1049                                 data_shndx, reloc.get_r_offset(),
1050                                 reloc.get_r_addend());
1051           else
1052             {
1053               gold_assert(lsym.get_st_value() == 0);
1054               unsigned int shndx = lsym.get_st_shndx();
1055               bool is_ordinary;
1056               shndx = object->adjust_sym_shndx(r_sym, shndx,
1057                                                &is_ordinary);
1058               if (!is_ordinary)
1059                 object->error(_("section symbol %u has bad shndx %u"),
1060                               r_sym, shndx);
1061               else
1062                 rela_dyn->add_local_section(object, shndx,
1063                                             r_type, output_section,
1064                                             data_shndx, reloc.get_r_offset(),
1065                                             reloc.get_r_addend());
1066             }
1067         }
1068       break;
1069
1070     case elfcpp::R_X86_64_PC64:
1071     case elfcpp::R_X86_64_PC32:
1072     case elfcpp::R_X86_64_PC16:
1073     case elfcpp::R_X86_64_PC8:
1074       break;
1075
1076     case elfcpp::R_X86_64_PLT32:
1077       // Since we know this is a local symbol, we can handle this as a
1078       // PC32 reloc.
1079       break;
1080
1081     case elfcpp::R_X86_64_GOTPC32:
1082     case elfcpp::R_X86_64_GOTOFF64:
1083     case elfcpp::R_X86_64_GOTPC64:
1084     case elfcpp::R_X86_64_PLTOFF64:
1085       // We need a GOT section.
1086       target->got_section(symtab, layout);
1087       // For PLTOFF64, we'd normally want a PLT section, but since we
1088       // know this is a local symbol, no PLT is needed.
1089       break;
1090
1091     case elfcpp::R_X86_64_GOT64:
1092     case elfcpp::R_X86_64_GOT32:
1093     case elfcpp::R_X86_64_GOTPCREL64:
1094     case elfcpp::R_X86_64_GOTPCREL:
1095     case elfcpp::R_X86_64_GOTPLT64:
1096       {
1097         // The symbol requires a GOT entry.
1098         Output_data_got<64, false>* got = target->got_section(symtab, layout);
1099         unsigned int r_sym = elfcpp::elf_r_sym<64>(reloc.get_r_info());
1100         if (got->add_local(object, r_sym, GOT_TYPE_STANDARD))
1101           {
1102             // If we are generating a shared object, we need to add a
1103             // dynamic relocation for this symbol's GOT entry.
1104             if (parameters->options().output_is_position_independent())
1105               {
1106                 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
1107                 // R_X86_64_RELATIVE assumes a 64-bit relocation.
1108                 if (r_type != elfcpp::R_X86_64_GOT32)
1109                   rela_dyn->add_local_relative(
1110                       object, r_sym, elfcpp::R_X86_64_RELATIVE, got,
1111                       object->local_got_offset(r_sym, GOT_TYPE_STANDARD), 0);
1112                 else
1113                   {
1114                     this->check_non_pic(object, r_type);
1115
1116                     gold_assert(lsym.get_st_type() != elfcpp::STT_SECTION);
1117                     rela_dyn->add_local(
1118                         object, r_sym, r_type, got,
1119                         object->local_got_offset(r_sym, GOT_TYPE_STANDARD), 0);
1120                   }
1121               }
1122           }
1123         // For GOTPLT64, we'd normally want a PLT section, but since
1124         // we know this is a local symbol, no PLT is needed.
1125       }
1126       break;
1127
1128     case elfcpp::R_X86_64_COPY:
1129     case elfcpp::R_X86_64_GLOB_DAT:
1130     case elfcpp::R_X86_64_JUMP_SLOT:
1131     case elfcpp::R_X86_64_RELATIVE:
1132       // These are outstanding tls relocs, which are unexpected when linking
1133     case elfcpp::R_X86_64_TPOFF64:
1134     case elfcpp::R_X86_64_DTPMOD64:
1135     case elfcpp::R_X86_64_TLSDESC:
1136       gold_error(_("%s: unexpected reloc %u in object file"),
1137                  object->name().c_str(), r_type);
1138       break;
1139
1140       // These are initial tls relocs, which are expected when linking
1141     case elfcpp::R_X86_64_TLSGD:            // Global-dynamic
1142     case elfcpp::R_X86_64_GOTPC32_TLSDESC:  // Global-dynamic (from ~oliva url)
1143     case elfcpp::R_X86_64_TLSDESC_CALL:
1144     case elfcpp::R_X86_64_TLSLD:            // Local-dynamic
1145     case elfcpp::R_X86_64_DTPOFF32:
1146     case elfcpp::R_X86_64_DTPOFF64:
1147     case elfcpp::R_X86_64_GOTTPOFF:         // Initial-exec
1148     case elfcpp::R_X86_64_TPOFF32:          // Local-exec
1149       {
1150         bool output_is_shared = parameters->options().shared();
1151         const tls::Tls_optimization optimized_type
1152             = Target_x86_64::optimize_tls_reloc(!output_is_shared, r_type);
1153         switch (r_type)
1154           {
1155           case elfcpp::R_X86_64_TLSGD:       // General-dynamic
1156             if (optimized_type == tls::TLSOPT_NONE)
1157               {
1158                 // Create a pair of GOT entries for the module index and
1159                 // dtv-relative offset.
1160                 Output_data_got<64, false>* got
1161                     = target->got_section(symtab, layout);
1162                 unsigned int r_sym = elfcpp::elf_r_sym<64>(reloc.get_r_info());
1163                 unsigned int shndx = lsym.get_st_shndx();
1164                 bool is_ordinary;
1165                 shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
1166                 if (!is_ordinary)
1167                   object->error(_("local symbol %u has bad shndx %u"),
1168                               r_sym, shndx);
1169                 else
1170                   got->add_local_pair_with_rela(object, r_sym,
1171                                                 shndx,
1172                                                 GOT_TYPE_TLS_PAIR,
1173                                                 target->rela_dyn_section(layout),
1174                                                 elfcpp::R_X86_64_DTPMOD64, 0);
1175               }
1176             else if (optimized_type != tls::TLSOPT_TO_LE)
1177               unsupported_reloc_local(object, r_type);
1178             break;
1179
1180           case elfcpp::R_X86_64_GOTPC32_TLSDESC:
1181             target->define_tls_base_symbol(symtab, layout);
1182             if (optimized_type == tls::TLSOPT_NONE)
1183               {
1184                 // Create reserved PLT and GOT entries for the resolver.
1185                 target->reserve_tlsdesc_entries(symtab, layout);
1186
1187                 // Generate a double GOT entry with an R_X86_64_TLSDESC reloc.
1188                 Output_data_got<64, false>* got
1189                     = target->got_section(symtab, layout);
1190                 unsigned int r_sym = elfcpp::elf_r_sym<64>(reloc.get_r_info());
1191                 unsigned int shndx = lsym.get_st_shndx();
1192                 bool is_ordinary;
1193                 shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
1194                 if (!is_ordinary)
1195                   object->error(_("local symbol %u has bad shndx %u"),
1196                               r_sym, shndx);
1197                 else
1198                   got->add_local_pair_with_rela(object, r_sym,
1199                                                 shndx,
1200                                                 GOT_TYPE_TLS_DESC,
1201                                                 target->rela_dyn_section(layout),
1202                                                 elfcpp::R_X86_64_TLSDESC, 0);
1203               }
1204             else if (optimized_type != tls::TLSOPT_TO_LE)
1205               unsupported_reloc_local(object, r_type);
1206             break;
1207
1208           case elfcpp::R_X86_64_TLSDESC_CALL:
1209             break;
1210
1211           case elfcpp::R_X86_64_TLSLD:       // Local-dynamic
1212             if (optimized_type == tls::TLSOPT_NONE)
1213               {
1214                 // Create a GOT entry for the module index.
1215                 target->got_mod_index_entry(symtab, layout, object);
1216               }
1217             else if (optimized_type != tls::TLSOPT_TO_LE)
1218               unsupported_reloc_local(object, r_type);
1219             break;
1220
1221           case elfcpp::R_X86_64_DTPOFF32:
1222           case elfcpp::R_X86_64_DTPOFF64:
1223             break;
1224
1225           case elfcpp::R_X86_64_GOTTPOFF:    // Initial-exec
1226             layout->set_has_static_tls();
1227             if (optimized_type == tls::TLSOPT_NONE)
1228               {
1229                 // Create a GOT entry for the tp-relative offset.
1230                 Output_data_got<64, false>* got
1231                     = target->got_section(symtab, layout);
1232                 unsigned int r_sym = elfcpp::elf_r_sym<64>(reloc.get_r_info());
1233                 got->add_local_with_rela(object, r_sym, GOT_TYPE_TLS_OFFSET,
1234                                          target->rela_dyn_section(layout),
1235                                          elfcpp::R_X86_64_TPOFF64);
1236               }
1237             else if (optimized_type != tls::TLSOPT_TO_LE)
1238               unsupported_reloc_local(object, r_type);
1239             break;
1240
1241           case elfcpp::R_X86_64_TPOFF32:     // Local-exec
1242             layout->set_has_static_tls();
1243             if (output_is_shared)
1244               unsupported_reloc_local(object, r_type);
1245             break;
1246
1247           default:
1248             gold_unreachable();
1249           }
1250       }
1251       break;
1252
1253     case elfcpp::R_X86_64_SIZE32:
1254     case elfcpp::R_X86_64_SIZE64:
1255     default:
1256       gold_error(_("%s: unsupported reloc %u against local symbol"),
1257                  object->name().c_str(), r_type);
1258       break;
1259     }
1260 }
1261
1262
1263 // Report an unsupported relocation against a global symbol.
1264
1265 void
1266 Target_x86_64::Scan::unsupported_reloc_global(Sized_relobj<64, false>* object,
1267                                               unsigned int r_type,
1268                                               Symbol* gsym)
1269 {
1270   gold_error(_("%s: unsupported reloc %u against global symbol %s"),
1271              object->name().c_str(), r_type, gsym->demangled_name().c_str());
1272 }
1273
1274 // Scan a relocation for a global symbol.
1275
1276 inline void
1277 Target_x86_64::Scan::global(const General_options&,
1278                             Symbol_table* symtab,
1279                             Layout* layout,
1280                             Target_x86_64* target,
1281                             Sized_relobj<64, false>* object,
1282                             unsigned int data_shndx,
1283                             Output_section* output_section,
1284                             const elfcpp::Rela<64, false>& reloc,
1285                             unsigned int r_type,
1286                             Symbol* gsym)
1287 {
1288   switch (r_type)
1289     {
1290     case elfcpp::R_X86_64_NONE:
1291     case elfcpp::R_386_GNU_VTINHERIT:
1292     case elfcpp::R_386_GNU_VTENTRY:
1293       break;
1294
1295     case elfcpp::R_X86_64_64:
1296     case elfcpp::R_X86_64_32:
1297     case elfcpp::R_X86_64_32S:
1298     case elfcpp::R_X86_64_16:
1299     case elfcpp::R_X86_64_8:
1300       {
1301         // Make a PLT entry if necessary.
1302         if (gsym->needs_plt_entry())
1303           {
1304             target->make_plt_entry(symtab, layout, gsym);
1305             // Since this is not a PC-relative relocation, we may be
1306             // taking the address of a function. In that case we need to
1307             // set the entry in the dynamic symbol table to the address of
1308             // the PLT entry.
1309             if (gsym->is_from_dynobj() && !parameters->options().shared())
1310               gsym->set_needs_dynsym_value();
1311           }
1312         // Make a dynamic relocation if necessary.
1313         if (gsym->needs_dynamic_reloc(Symbol::ABSOLUTE_REF))
1314           {
1315             if (gsym->may_need_copy_reloc())
1316               {
1317                 target->copy_reloc(symtab, layout, object,
1318                                    data_shndx, output_section, gsym, reloc);
1319               }
1320             else if (r_type == elfcpp::R_X86_64_64
1321                      && gsym->can_use_relative_reloc(false))
1322               {
1323                 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
1324                 rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_RELATIVE,
1325                                               output_section, object,
1326                                               data_shndx, reloc.get_r_offset(),
1327                                               reloc.get_r_addend());
1328               }
1329             else
1330               {
1331                 this->check_non_pic(object, r_type);
1332                 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
1333                 rela_dyn->add_global(gsym, r_type, output_section, object,
1334                                      data_shndx, reloc.get_r_offset(),
1335                                      reloc.get_r_addend());
1336               }
1337           }
1338       }
1339       break;
1340
1341     case elfcpp::R_X86_64_PC64:
1342     case elfcpp::R_X86_64_PC32:
1343     case elfcpp::R_X86_64_PC16:
1344     case elfcpp::R_X86_64_PC8:
1345       {
1346         // Make a PLT entry if necessary.
1347         if (gsym->needs_plt_entry())
1348           target->make_plt_entry(symtab, layout, gsym);
1349         // Make a dynamic relocation if necessary.
1350         int flags = Symbol::NON_PIC_REF;
1351         if (gsym->type() == elfcpp::STT_FUNC)
1352           flags |= Symbol::FUNCTION_CALL;
1353         if (gsym->needs_dynamic_reloc(flags))
1354           {
1355             if (gsym->may_need_copy_reloc())
1356               {
1357                 target->copy_reloc(symtab, layout, object,
1358                                    data_shndx, output_section, gsym, reloc);
1359               }
1360             else
1361               {
1362                 this->check_non_pic(object, r_type);
1363                 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
1364                 rela_dyn->add_global(gsym, r_type, output_section, object,
1365                                      data_shndx, reloc.get_r_offset(),
1366                                      reloc.get_r_addend());
1367               }
1368           }
1369       }
1370       break;
1371
1372     case elfcpp::R_X86_64_GOT64:
1373     case elfcpp::R_X86_64_GOT32:
1374     case elfcpp::R_X86_64_GOTPCREL64:
1375     case elfcpp::R_X86_64_GOTPCREL:
1376     case elfcpp::R_X86_64_GOTPLT64:
1377       {
1378         // The symbol requires a GOT entry.
1379         Output_data_got<64, false>* got = target->got_section(symtab, layout);
1380         if (gsym->final_value_is_known())
1381           got->add_global(gsym, GOT_TYPE_STANDARD);
1382         else
1383           {
1384             // If this symbol is not fully resolved, we need to add a
1385             // dynamic relocation for it.
1386             Reloc_section* rela_dyn = target->rela_dyn_section(layout);
1387             if (gsym->is_from_dynobj()
1388                 || gsym->is_undefined()
1389                 || gsym->is_preemptible())
1390               got->add_global_with_rela(gsym, GOT_TYPE_STANDARD, rela_dyn,
1391                                         elfcpp::R_X86_64_GLOB_DAT);
1392             else
1393               {
1394                 if (got->add_global(gsym, GOT_TYPE_STANDARD))
1395                   rela_dyn->add_global_relative(
1396                       gsym, elfcpp::R_X86_64_RELATIVE, got,
1397                       gsym->got_offset(GOT_TYPE_STANDARD), 0);
1398               }
1399           }
1400         // For GOTPLT64, we also need a PLT entry (but only if the
1401         // symbol is not fully resolved).
1402         if (r_type == elfcpp::R_X86_64_GOTPLT64
1403             && !gsym->final_value_is_known())
1404           target->make_plt_entry(symtab, layout, gsym);
1405       }
1406       break;
1407
1408     case elfcpp::R_X86_64_PLT32:
1409       // If the symbol is fully resolved, this is just a PC32 reloc.
1410       // Otherwise we need a PLT entry.
1411       if (gsym->final_value_is_known())
1412         break;
1413       // If building a shared library, we can also skip the PLT entry
1414       // if the symbol is defined in the output file and is protected
1415       // or hidden.
1416       if (gsym->is_defined()
1417           && !gsym->is_from_dynobj()
1418           && !gsym->is_preemptible())
1419         break;
1420       target->make_plt_entry(symtab, layout, gsym);
1421       break;
1422
1423     case elfcpp::R_X86_64_GOTPC32:
1424     case elfcpp::R_X86_64_GOTOFF64:
1425     case elfcpp::R_X86_64_GOTPC64:
1426     case elfcpp::R_X86_64_PLTOFF64:
1427       // We need a GOT section.
1428       target->got_section(symtab, layout);
1429       // For PLTOFF64, we also need a PLT entry (but only if the
1430       // symbol is not fully resolved).
1431       if (r_type == elfcpp::R_X86_64_PLTOFF64
1432           && !gsym->final_value_is_known())
1433         target->make_plt_entry(symtab, layout, gsym);
1434       break;
1435
1436     case elfcpp::R_X86_64_COPY:
1437     case elfcpp::R_X86_64_GLOB_DAT:
1438     case elfcpp::R_X86_64_JUMP_SLOT:
1439     case elfcpp::R_X86_64_RELATIVE:
1440       // These are outstanding tls relocs, which are unexpected when linking
1441     case elfcpp::R_X86_64_TPOFF64:
1442     case elfcpp::R_X86_64_DTPMOD64:
1443     case elfcpp::R_X86_64_TLSDESC:
1444       gold_error(_("%s: unexpected reloc %u in object file"),
1445                  object->name().c_str(), r_type);
1446       break;
1447
1448       // These are initial tls relocs, which are expected for global()
1449     case elfcpp::R_X86_64_TLSGD:            // Global-dynamic
1450     case elfcpp::R_X86_64_GOTPC32_TLSDESC:  // Global-dynamic (from ~oliva url)
1451     case elfcpp::R_X86_64_TLSDESC_CALL:
1452     case elfcpp::R_X86_64_TLSLD:            // Local-dynamic
1453     case elfcpp::R_X86_64_DTPOFF32:
1454     case elfcpp::R_X86_64_DTPOFF64:
1455     case elfcpp::R_X86_64_GOTTPOFF:         // Initial-exec
1456     case elfcpp::R_X86_64_TPOFF32:          // Local-exec
1457       {
1458         const bool is_final = gsym->final_value_is_known();
1459         const tls::Tls_optimization optimized_type
1460             = Target_x86_64::optimize_tls_reloc(is_final, r_type);
1461         switch (r_type)
1462           {
1463           case elfcpp::R_X86_64_TLSGD:       // General-dynamic
1464             if (optimized_type == tls::TLSOPT_NONE)
1465               {
1466                 // Create a pair of GOT entries for the module index and
1467                 // dtv-relative offset.
1468                 Output_data_got<64, false>* got
1469                     = target->got_section(symtab, layout);
1470                 got->add_global_pair_with_rela(gsym, GOT_TYPE_TLS_PAIR,
1471                                                target->rela_dyn_section(layout),
1472                                                elfcpp::R_X86_64_DTPMOD64,
1473                                                elfcpp::R_X86_64_DTPOFF64);
1474               }
1475             else if (optimized_type == tls::TLSOPT_TO_IE)
1476               {
1477                 // Create a GOT entry for the tp-relative offset.
1478                 Output_data_got<64, false>* got
1479                     = target->got_section(symtab, layout);
1480                 got->add_global_with_rela(gsym, GOT_TYPE_TLS_OFFSET,
1481                                           target->rela_dyn_section(layout),
1482                                           elfcpp::R_X86_64_TPOFF64);
1483               }
1484             else if (optimized_type != tls::TLSOPT_TO_LE)
1485               unsupported_reloc_global(object, r_type, gsym);
1486             break;
1487
1488           case elfcpp::R_X86_64_GOTPC32_TLSDESC:
1489             target->define_tls_base_symbol(symtab, layout);
1490             if (optimized_type == tls::TLSOPT_NONE)
1491               {
1492                 // Create reserved PLT and GOT entries for the resolver.
1493                 target->reserve_tlsdesc_entries(symtab, layout);
1494
1495                 // Create a double GOT entry with an R_X86_64_TLSDESC reloc.
1496                 Output_data_got<64, false>* got
1497                     = target->got_section(symtab, layout);
1498                 got->add_global_pair_with_rela(gsym, GOT_TYPE_TLS_DESC,
1499                                                target->rela_dyn_section(layout),
1500                                                elfcpp::R_X86_64_TLSDESC, 0);
1501               }
1502             else if (optimized_type == tls::TLSOPT_TO_IE)
1503               {
1504                 // Create a GOT entry for the tp-relative offset.
1505                 Output_data_got<64, false>* got
1506                     = target->got_section(symtab, layout);
1507                 got->add_global_with_rela(gsym, GOT_TYPE_TLS_OFFSET,
1508                                           target->rela_dyn_section(layout),
1509                                           elfcpp::R_X86_64_TPOFF64);
1510               }
1511             else if (optimized_type != tls::TLSOPT_TO_LE)
1512               unsupported_reloc_global(object, r_type, gsym);
1513             break;
1514
1515           case elfcpp::R_X86_64_TLSDESC_CALL:
1516             break;
1517
1518           case elfcpp::R_X86_64_TLSLD:       // Local-dynamic
1519             if (optimized_type == tls::TLSOPT_NONE)
1520               {
1521                 // Create a GOT entry for the module index.
1522                 target->got_mod_index_entry(symtab, layout, object);
1523               }
1524             else if (optimized_type != tls::TLSOPT_TO_LE)
1525               unsupported_reloc_global(object, r_type, gsym);
1526             break;
1527
1528           case elfcpp::R_X86_64_DTPOFF32:
1529           case elfcpp::R_X86_64_DTPOFF64:
1530             break;
1531
1532           case elfcpp::R_X86_64_GOTTPOFF:    // Initial-exec
1533             layout->set_has_static_tls();
1534             if (optimized_type == tls::TLSOPT_NONE)
1535               {
1536                 // Create a GOT entry for the tp-relative offset.
1537                 Output_data_got<64, false>* got
1538                     = target->got_section(symtab, layout);
1539                 got->add_global_with_rela(gsym, GOT_TYPE_TLS_OFFSET,
1540                                           target->rela_dyn_section(layout),
1541                                           elfcpp::R_X86_64_TPOFF64);
1542               }
1543             else if (optimized_type != tls::TLSOPT_TO_LE)
1544               unsupported_reloc_global(object, r_type, gsym);
1545             break;
1546
1547           case elfcpp::R_X86_64_TPOFF32:     // Local-exec
1548             layout->set_has_static_tls();
1549             if (parameters->options().shared())
1550               unsupported_reloc_local(object, r_type);
1551             break;
1552
1553           default:
1554             gold_unreachable();
1555           }
1556       }
1557       break;
1558
1559     case elfcpp::R_X86_64_SIZE32:
1560     case elfcpp::R_X86_64_SIZE64:
1561     default:
1562       gold_error(_("%s: unsupported reloc %u against global symbol %s"),
1563                  object->name().c_str(), r_type,
1564                  gsym->demangled_name().c_str());
1565       break;
1566     }
1567 }
1568
1569 void
1570 Target_x86_64::gc_process_relocs(const General_options& options,
1571                                  Symbol_table* symtab,
1572                                  Layout* layout,
1573                                  Sized_relobj<64, false>* object,
1574                                  unsigned int data_shndx,
1575                                  unsigned int sh_type,
1576                                  const unsigned char* prelocs,
1577                                  size_t reloc_count,
1578                                  Output_section* output_section,
1579                                  bool needs_special_offset_handling,
1580                                  size_t local_symbol_count,
1581                                  const unsigned char* plocal_symbols)
1582 {
1583
1584   if (sh_type == elfcpp::SHT_REL)
1585     {
1586       return;
1587     }
1588
1589    gold::gc_process_relocs<64, false, Target_x86_64, elfcpp::SHT_RELA,
1590                            Target_x86_64::Scan>(
1591     options,
1592     symtab,
1593     layout,
1594     this,
1595     object,
1596     data_shndx,
1597     prelocs,
1598     reloc_count,
1599     output_section,
1600     needs_special_offset_handling,
1601     local_symbol_count,
1602     plocal_symbols);
1603
1604 }
1605 // Scan relocations for a section.
1606
1607 void
1608 Target_x86_64::scan_relocs(const General_options& options,
1609                            Symbol_table* symtab,
1610                            Layout* layout,
1611                            Sized_relobj<64, false>* object,
1612                            unsigned int data_shndx,
1613                            unsigned int sh_type,
1614                            const unsigned char* prelocs,
1615                            size_t reloc_count,
1616                            Output_section* output_section,
1617                            bool needs_special_offset_handling,
1618                            size_t local_symbol_count,
1619                            const unsigned char* plocal_symbols)
1620 {
1621   if (sh_type == elfcpp::SHT_REL)
1622     {
1623       gold_error(_("%s: unsupported REL reloc section"),
1624                  object->name().c_str());
1625       return;
1626     }
1627
1628   gold::scan_relocs<64, false, Target_x86_64, elfcpp::SHT_RELA,
1629       Target_x86_64::Scan>(
1630     options,
1631     symtab,
1632     layout,
1633     this,
1634     object,
1635     data_shndx,
1636     prelocs,
1637     reloc_count,
1638     output_section,
1639     needs_special_offset_handling,
1640     local_symbol_count,
1641     plocal_symbols);
1642 }
1643
1644 // Finalize the sections.
1645
1646 void
1647 Target_x86_64::do_finalize_sections(Layout* layout)
1648 {
1649   // Fill in some more dynamic tags.
1650   Output_data_dynamic* const odyn = layout->dynamic_data();
1651   if (odyn != NULL)
1652     {
1653       if (this->got_plt_ != NULL)
1654         odyn->add_section_address(elfcpp::DT_PLTGOT, this->got_plt_);
1655
1656       if (this->plt_ != NULL)
1657         {
1658           const Output_data* od = this->plt_->rel_plt();
1659           odyn->add_section_size(elfcpp::DT_PLTRELSZ, od);
1660           odyn->add_section_address(elfcpp::DT_JMPREL, od);
1661           odyn->add_constant(elfcpp::DT_PLTREL, elfcpp::DT_RELA);
1662           if (this->plt_->has_tlsdesc_entry())
1663             {
1664               unsigned int plt_offset = this->plt_->get_tlsdesc_plt_offset();
1665               unsigned int got_offset = this->plt_->get_tlsdesc_got_offset();
1666               this->got_->finalize_data_size();
1667               odyn->add_section_plus_offset(elfcpp::DT_TLSDESC_PLT,
1668                                             this->plt_, plt_offset);
1669               odyn->add_section_plus_offset(elfcpp::DT_TLSDESC_GOT,
1670                                             this->got_, got_offset);
1671             }
1672         }
1673
1674       if (this->rela_dyn_ != NULL)
1675         {
1676           const Output_data* od = this->rela_dyn_;
1677           odyn->add_section_address(elfcpp::DT_RELA, od);
1678           odyn->add_section_size(elfcpp::DT_RELASZ, od);
1679           odyn->add_constant(elfcpp::DT_RELAENT,
1680                              elfcpp::Elf_sizes<64>::rela_size);
1681         }
1682
1683       if (!parameters->options().shared())
1684         {
1685           // The value of the DT_DEBUG tag is filled in by the dynamic
1686           // linker at run time, and used by the debugger.
1687           odyn->add_constant(elfcpp::DT_DEBUG, 0);
1688         }
1689     }
1690
1691   // Emit any relocs we saved in an attempt to avoid generating COPY
1692   // relocs.
1693   if (this->copy_relocs_.any_saved_relocs())
1694     this->copy_relocs_.emit(this->rela_dyn_section(layout));
1695 }
1696
1697 // Perform a relocation.
1698
1699 inline bool
1700 Target_x86_64::Relocate::relocate(const Relocate_info<64, false>* relinfo,
1701                                   Target_x86_64* target,
1702                                   Output_section*,
1703                                   size_t relnum,
1704                                   const elfcpp::Rela<64, false>& rela,
1705                                   unsigned int r_type,
1706                                   const Sized_symbol<64>* gsym,
1707                                   const Symbol_value<64>* psymval,
1708                                   unsigned char* view,
1709                                   elfcpp::Elf_types<64>::Elf_Addr address,
1710                                   section_size_type view_size)
1711 {
1712   if (this->skip_call_tls_get_addr_)
1713     {
1714       if ((r_type != elfcpp::R_X86_64_PLT32
1715            && r_type != elfcpp::R_X86_64_PC32)
1716           || gsym == NULL
1717           || strcmp(gsym->name(), "__tls_get_addr") != 0)
1718         {
1719           gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
1720                                  _("missing expected TLS relocation"));
1721         }
1722       else
1723         {
1724           this->skip_call_tls_get_addr_ = false;
1725           return false;
1726         }
1727     }
1728
1729   // Pick the value to use for symbols defined in shared objects.
1730   Symbol_value<64> symval;
1731   if (gsym != NULL
1732       && gsym->use_plt_offset(r_type == elfcpp::R_X86_64_PC64
1733                               || r_type == elfcpp::R_X86_64_PC32
1734                               || r_type == elfcpp::R_X86_64_PC16
1735                               || r_type == elfcpp::R_X86_64_PC8))
1736     {
1737       symval.set_output_value(target->plt_section()->address()
1738                               + gsym->plt_offset());
1739       psymval = &symval;
1740     }
1741
1742   const Sized_relobj<64, false>* object = relinfo->object;
1743   const elfcpp::Elf_Xword addend = rela.get_r_addend();
1744
1745   // Get the GOT offset if needed.
1746   // The GOT pointer points to the end of the GOT section.
1747   // We need to subtract the size of the GOT section to get
1748   // the actual offset to use in the relocation.
1749   bool have_got_offset = false;
1750   unsigned int got_offset = 0;
1751   switch (r_type)
1752     {
1753     case elfcpp::R_X86_64_GOT32:
1754     case elfcpp::R_X86_64_GOT64:
1755     case elfcpp::R_X86_64_GOTPLT64:
1756     case elfcpp::R_X86_64_GOTPCREL:
1757     case elfcpp::R_X86_64_GOTPCREL64:
1758       if (gsym != NULL)
1759         {
1760           gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
1761           got_offset = gsym->got_offset(GOT_TYPE_STANDARD) - target->got_size();
1762         }
1763       else
1764         {
1765           unsigned int r_sym = elfcpp::elf_r_sym<64>(rela.get_r_info());
1766           gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD));
1767           got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD)
1768                         - target->got_size());
1769         }
1770       have_got_offset = true;
1771       break;
1772
1773     default:
1774       break;
1775     }
1776
1777   switch (r_type)
1778     {
1779     case elfcpp::R_X86_64_NONE:
1780     case elfcpp::R_386_GNU_VTINHERIT:
1781     case elfcpp::R_386_GNU_VTENTRY:
1782       break;
1783
1784     case elfcpp::R_X86_64_64:
1785       Relocate_functions<64, false>::rela64(view, object, psymval, addend);
1786       break;
1787
1788     case elfcpp::R_X86_64_PC64:
1789       Relocate_functions<64, false>::pcrela64(view, object, psymval, addend,
1790                                               address);
1791       break;
1792
1793     case elfcpp::R_X86_64_32:
1794       // FIXME: we need to verify that value + addend fits into 32 bits:
1795       //    uint64_t x = value + addend;
1796       //    x == static_cast<uint64_t>(static_cast<uint32_t>(x))
1797       // Likewise for other <=32-bit relocations (but see R_X86_64_32S).
1798       Relocate_functions<64, false>::rela32(view, object, psymval, addend);
1799       break;
1800
1801     case elfcpp::R_X86_64_32S:
1802       // FIXME: we need to verify that value + addend fits into 32 bits:
1803       //    int64_t x = value + addend;   // note this quantity is signed!
1804       //    x == static_cast<int64_t>(static_cast<int32_t>(x))
1805       Relocate_functions<64, false>::rela32(view, object, psymval, addend);
1806       break;
1807
1808     case elfcpp::R_X86_64_PC32:
1809       Relocate_functions<64, false>::pcrela32(view, object, psymval, addend,
1810                                               address);
1811       break;
1812
1813     case elfcpp::R_X86_64_16:
1814       Relocate_functions<64, false>::rela16(view, object, psymval, addend);
1815       break;
1816
1817     case elfcpp::R_X86_64_PC16:
1818       Relocate_functions<64, false>::pcrela16(view, object, psymval, addend,
1819                                               address);
1820       break;
1821
1822     case elfcpp::R_X86_64_8:
1823       Relocate_functions<64, false>::rela8(view, object, psymval, addend);
1824       break;
1825
1826     case elfcpp::R_X86_64_PC8:
1827       Relocate_functions<64, false>::pcrela8(view, object, psymval, addend,
1828                                              address);
1829       break;
1830
1831     case elfcpp::R_X86_64_PLT32:
1832       gold_assert(gsym == NULL
1833                   || gsym->has_plt_offset()
1834                   || gsym->final_value_is_known()
1835                   || (gsym->is_defined()
1836                       && !gsym->is_from_dynobj()
1837                       && !gsym->is_preemptible()));
1838       // Note: while this code looks the same as for R_X86_64_PC32, it
1839       // behaves differently because psymval was set to point to
1840       // the PLT entry, rather than the symbol, in Scan::global().
1841       Relocate_functions<64, false>::pcrela32(view, object, psymval, addend,
1842                                               address);
1843       break;
1844
1845     case elfcpp::R_X86_64_PLTOFF64:
1846       {
1847         gold_assert(gsym);
1848         gold_assert(gsym->has_plt_offset()
1849                     || gsym->final_value_is_known());
1850         elfcpp::Elf_types<64>::Elf_Addr got_address;
1851         got_address = target->got_section(NULL, NULL)->address();
1852         Relocate_functions<64, false>::rela64(view, object, psymval,
1853                                               addend - got_address);
1854       }
1855
1856     case elfcpp::R_X86_64_GOT32:
1857       gold_assert(have_got_offset);
1858       Relocate_functions<64, false>::rela32(view, got_offset, addend);
1859       break;
1860
1861     case elfcpp::R_X86_64_GOTPC32:
1862       {
1863         gold_assert(gsym);
1864         elfcpp::Elf_types<64>::Elf_Addr value;
1865         value = target->got_plt_section()->address();
1866         Relocate_functions<64, false>::pcrela32(view, value, addend, address);
1867       }
1868       break;
1869
1870     case elfcpp::R_X86_64_GOT64:
1871       // The ABI doc says "Like GOT64, but indicates a PLT entry is needed."
1872       // Since we always add a PLT entry, this is equivalent.
1873     case elfcpp::R_X86_64_GOTPLT64:
1874       gold_assert(have_got_offset);
1875       Relocate_functions<64, false>::rela64(view, got_offset, addend);
1876       break;
1877
1878     case elfcpp::R_X86_64_GOTPC64:
1879       {
1880         gold_assert(gsym);
1881         elfcpp::Elf_types<64>::Elf_Addr value;
1882         value = target->got_plt_section()->address();
1883         Relocate_functions<64, false>::pcrela64(view, value, addend, address);
1884       }
1885       break;
1886
1887     case elfcpp::R_X86_64_GOTOFF64:
1888       {
1889         elfcpp::Elf_types<64>::Elf_Addr value;
1890         value = (psymval->value(object, 0)
1891                  - target->got_plt_section()->address());
1892         Relocate_functions<64, false>::rela64(view, value, addend);
1893       }
1894       break;
1895
1896     case elfcpp::R_X86_64_GOTPCREL:
1897       {
1898         gold_assert(have_got_offset);
1899         elfcpp::Elf_types<64>::Elf_Addr value;
1900         value = target->got_plt_section()->address() + got_offset;
1901         Relocate_functions<64, false>::pcrela32(view, value, addend, address);
1902       }
1903       break;
1904
1905     case elfcpp::R_X86_64_GOTPCREL64:
1906       {
1907         gold_assert(have_got_offset);
1908         elfcpp::Elf_types<64>::Elf_Addr value;
1909         value = target->got_plt_section()->address() + got_offset;
1910         Relocate_functions<64, false>::pcrela64(view, value, addend, address);
1911       }
1912       break;
1913
1914     case elfcpp::R_X86_64_COPY:
1915     case elfcpp::R_X86_64_GLOB_DAT:
1916     case elfcpp::R_X86_64_JUMP_SLOT:
1917     case elfcpp::R_X86_64_RELATIVE:
1918       // These are outstanding tls relocs, which are unexpected when linking
1919     case elfcpp::R_X86_64_TPOFF64:
1920     case elfcpp::R_X86_64_DTPMOD64:
1921     case elfcpp::R_X86_64_TLSDESC:
1922       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
1923                              _("unexpected reloc %u in object file"),
1924                              r_type);
1925       break;
1926
1927       // These are initial tls relocs, which are expected when linking
1928     case elfcpp::R_X86_64_TLSGD:            // Global-dynamic
1929     case elfcpp::R_X86_64_GOTPC32_TLSDESC:  // Global-dynamic (from ~oliva url)
1930     case elfcpp::R_X86_64_TLSDESC_CALL:
1931     case elfcpp::R_X86_64_TLSLD:            // Local-dynamic
1932     case elfcpp::R_X86_64_DTPOFF32:
1933     case elfcpp::R_X86_64_DTPOFF64:
1934     case elfcpp::R_X86_64_GOTTPOFF:         // Initial-exec
1935     case elfcpp::R_X86_64_TPOFF32:          // Local-exec
1936       this->relocate_tls(relinfo, target, relnum, rela, r_type, gsym, psymval,
1937                          view, address, view_size);
1938       break;
1939
1940     case elfcpp::R_X86_64_SIZE32:
1941     case elfcpp::R_X86_64_SIZE64:
1942     default:
1943       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
1944                              _("unsupported reloc %u"),
1945                              r_type);
1946       break;
1947     }
1948
1949   return true;
1950 }
1951
1952 // Perform a TLS relocation.
1953
1954 inline void
1955 Target_x86_64::Relocate::relocate_tls(const Relocate_info<64, false>* relinfo,
1956                                       Target_x86_64* target,
1957                                       size_t relnum,
1958                                       const elfcpp::Rela<64, false>& rela,
1959                                       unsigned int r_type,
1960                                       const Sized_symbol<64>* gsym,
1961                                       const Symbol_value<64>* psymval,
1962                                       unsigned char* view,
1963                                       elfcpp::Elf_types<64>::Elf_Addr address,
1964                                       section_size_type view_size)
1965 {
1966   Output_segment* tls_segment = relinfo->layout->tls_segment();
1967
1968   const Sized_relobj<64, false>* object = relinfo->object;
1969   const elfcpp::Elf_Xword addend = rela.get_r_addend();
1970
1971   elfcpp::Elf_types<64>::Elf_Addr value = psymval->value(relinfo->object, 0);
1972
1973   const bool is_final = (gsym == NULL
1974                          ? !parameters->options().output_is_position_independent()
1975                          : gsym->final_value_is_known());
1976   const tls::Tls_optimization optimized_type
1977       = Target_x86_64::optimize_tls_reloc(is_final, r_type);
1978   switch (r_type)
1979     {
1980     case elfcpp::R_X86_64_TLSGD:            // Global-dynamic
1981       this->saw_tls_block_reloc_ = true;
1982       if (optimized_type == tls::TLSOPT_TO_LE)
1983         {
1984           gold_assert(tls_segment != NULL);
1985           this->tls_gd_to_le(relinfo, relnum, tls_segment,
1986                              rela, r_type, value, view,
1987                              view_size);
1988           break;
1989         }
1990       else
1991         {
1992           unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE
1993                                    ? GOT_TYPE_TLS_OFFSET
1994                                    : GOT_TYPE_TLS_PAIR);
1995           unsigned int got_offset;
1996           if (gsym != NULL)
1997             {
1998               gold_assert(gsym->has_got_offset(got_type));
1999               got_offset = gsym->got_offset(got_type) - target->got_size();
2000             }
2001           else
2002             {
2003               unsigned int r_sym = elfcpp::elf_r_sym<64>(rela.get_r_info());
2004               gold_assert(object->local_has_got_offset(r_sym, got_type));
2005               got_offset = (object->local_got_offset(r_sym, got_type)
2006                             - target->got_size());
2007             }
2008           if (optimized_type == tls::TLSOPT_TO_IE)
2009             {
2010               gold_assert(tls_segment != NULL);
2011               value = target->got_plt_section()->address() + got_offset;
2012               this->tls_gd_to_ie(relinfo, relnum, tls_segment, rela, r_type,
2013                                  value, view, address, view_size);
2014               break;
2015             }
2016           else if (optimized_type == tls::TLSOPT_NONE)
2017             {
2018               // Relocate the field with the offset of the pair of GOT
2019               // entries.
2020               value = target->got_plt_section()->address() + got_offset;
2021               Relocate_functions<64, false>::pcrela32(view, value, addend,
2022                                                       address);
2023               break;
2024             }
2025         }
2026       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
2027                              _("unsupported reloc %u"), r_type);
2028       break;
2029
2030     case elfcpp::R_X86_64_GOTPC32_TLSDESC:  // Global-dynamic (from ~oliva url)
2031     case elfcpp::R_X86_64_TLSDESC_CALL:
2032       this->saw_tls_block_reloc_ = true;
2033       if (optimized_type == tls::TLSOPT_TO_LE)
2034         {
2035           gold_assert(tls_segment != NULL);
2036           this->tls_desc_gd_to_le(relinfo, relnum, tls_segment,
2037                                   rela, r_type, value, view,
2038                                   view_size);
2039           break;
2040         }
2041       else
2042         {
2043           unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE
2044                                    ? GOT_TYPE_TLS_OFFSET
2045                                    : GOT_TYPE_TLS_DESC);
2046           unsigned int got_offset;
2047           if (gsym != NULL)
2048             {
2049               gold_assert(gsym->has_got_offset(got_type));
2050               got_offset = gsym->got_offset(got_type) - target->got_size();
2051             }
2052           else
2053             {
2054               unsigned int r_sym = elfcpp::elf_r_sym<64>(rela.get_r_info());
2055               gold_assert(object->local_has_got_offset(r_sym, got_type));
2056               got_offset = (object->local_got_offset(r_sym, got_type)
2057                             - target->got_size());
2058             }
2059           if (optimized_type == tls::TLSOPT_TO_IE)
2060             {
2061               gold_assert(tls_segment != NULL);
2062               value = target->got_plt_section()->address() + got_offset;
2063               this->tls_desc_gd_to_ie(relinfo, relnum, tls_segment,
2064                                       rela, r_type, value, view, address,
2065                                       view_size);
2066               break;
2067             }
2068           else if (optimized_type == tls::TLSOPT_NONE)
2069             {
2070               if (r_type == elfcpp::R_X86_64_GOTPC32_TLSDESC)
2071                 {
2072                   // Relocate the field with the offset of the pair of GOT
2073                   // entries.
2074                   value = target->got_plt_section()->address() + got_offset;
2075                   Relocate_functions<64, false>::pcrela32(view, value, addend,
2076                                                           address);
2077                 }
2078               break;
2079             }
2080         }
2081       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
2082                              _("unsupported reloc %u"), r_type);
2083       break;
2084
2085     case elfcpp::R_X86_64_TLSLD:            // Local-dynamic
2086       this->saw_tls_block_reloc_ = true;
2087       if (optimized_type == tls::TLSOPT_TO_LE)
2088         {
2089           gold_assert(tls_segment != NULL);
2090           this->tls_ld_to_le(relinfo, relnum, tls_segment, rela, r_type,
2091                              value, view, view_size);
2092           break;
2093         }
2094       else if (optimized_type == tls::TLSOPT_NONE)
2095         {
2096           // Relocate the field with the offset of the GOT entry for
2097           // the module index.
2098           unsigned int got_offset;
2099           got_offset = (target->got_mod_index_entry(NULL, NULL, NULL)
2100                         - target->got_size());
2101           value = target->got_plt_section()->address() + got_offset;
2102           Relocate_functions<64, false>::pcrela32(view, value, addend,
2103                                                   address);
2104           break;
2105         }
2106       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
2107                              _("unsupported reloc %u"), r_type);
2108       break;
2109
2110     case elfcpp::R_X86_64_DTPOFF32:
2111       if (optimized_type == tls::TLSOPT_TO_LE)
2112         {
2113           // This relocation type is used in debugging information.
2114           // In that case we need to not optimize the value.  If we
2115           // haven't seen a TLSLD reloc, then we assume we should not
2116           // optimize this reloc.
2117           if (this->saw_tls_block_reloc_)
2118             {
2119               gold_assert(tls_segment != NULL);
2120               value -= tls_segment->memsz();
2121             }
2122         }
2123       Relocate_functions<64, false>::rela32(view, value, addend);
2124       break;
2125
2126     case elfcpp::R_X86_64_DTPOFF64:
2127       if (optimized_type == tls::TLSOPT_TO_LE)
2128         {
2129           // See R_X86_64_DTPOFF32, just above, for why we test this.
2130           if (this->saw_tls_block_reloc_)
2131             {
2132               gold_assert(tls_segment != NULL);
2133               value -= tls_segment->memsz();
2134             }
2135         }
2136       Relocate_functions<64, false>::rela64(view, value, addend);
2137       break;
2138
2139     case elfcpp::R_X86_64_GOTTPOFF:         // Initial-exec
2140       if (optimized_type == tls::TLSOPT_TO_LE)
2141         {
2142           gold_assert(tls_segment != NULL);
2143           Target_x86_64::Relocate::tls_ie_to_le(relinfo, relnum, tls_segment,
2144                                                 rela, r_type, value, view,
2145                                                 view_size);
2146           break;
2147         }
2148       else if (optimized_type == tls::TLSOPT_NONE)
2149         {
2150           // Relocate the field with the offset of the GOT entry for
2151           // the tp-relative offset of the symbol.
2152           unsigned int got_offset;
2153           if (gsym != NULL)
2154             {
2155               gold_assert(gsym->has_got_offset(GOT_TYPE_TLS_OFFSET));
2156               got_offset = (gsym->got_offset(GOT_TYPE_TLS_OFFSET)
2157                             - target->got_size());
2158             }
2159           else
2160             {
2161               unsigned int r_sym = elfcpp::elf_r_sym<64>(rela.get_r_info());
2162               gold_assert(object->local_has_got_offset(r_sym,
2163                                                        GOT_TYPE_TLS_OFFSET));
2164               got_offset = (object->local_got_offset(r_sym, GOT_TYPE_TLS_OFFSET)
2165                             - target->got_size());
2166             }
2167           value = target->got_plt_section()->address() + got_offset;
2168           Relocate_functions<64, false>::pcrela32(view, value, addend, address);
2169           break;
2170         }
2171       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
2172                              _("unsupported reloc type %u"),
2173                              r_type);
2174       break;
2175
2176     case elfcpp::R_X86_64_TPOFF32:          // Local-exec
2177       value -= tls_segment->memsz();
2178       Relocate_functions<64, false>::rela32(view, value, addend);
2179       break;
2180     }
2181 }
2182
2183 // Do a relocation in which we convert a TLS General-Dynamic to an
2184 // Initial-Exec.
2185
2186 inline void
2187 Target_x86_64::Relocate::tls_gd_to_ie(const Relocate_info<64, false>* relinfo,
2188                                       size_t relnum,
2189                                       Output_segment*,
2190                                       const elfcpp::Rela<64, false>& rela,
2191                                       unsigned int,
2192                                       elfcpp::Elf_types<64>::Elf_Addr value,
2193                                       unsigned char* view,
2194                                       elfcpp::Elf_types<64>::Elf_Addr address,
2195                                       section_size_type view_size)
2196 {
2197   // .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
2198   // .word 0x6666; rex64; call __tls_get_addr
2199   // ==> movq %fs:0,%rax; addq x@gottpoff(%rip),%rax
2200
2201   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -4);
2202   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 12);
2203
2204   tls::check_tls(relinfo, relnum, rela.get_r_offset(),
2205                  (memcmp(view - 4, "\x66\x48\x8d\x3d", 4) == 0));
2206   tls::check_tls(relinfo, relnum, rela.get_r_offset(),
2207                  (memcmp(view + 4, "\x66\x66\x48\xe8", 4) == 0));
2208
2209   memcpy(view - 4, "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x03\x05\0\0\0\0", 16);
2210
2211   const elfcpp::Elf_Xword addend = rela.get_r_addend();
2212   Relocate_functions<64, false>::pcrela32(view + 8, value, addend - 8, address);
2213
2214   // The next reloc should be a PLT32 reloc against __tls_get_addr.
2215   // We can skip it.
2216   this->skip_call_tls_get_addr_ = true;
2217 }
2218
2219 // Do a relocation in which we convert a TLS General-Dynamic to a
2220 // Local-Exec.
2221
2222 inline void
2223 Target_x86_64::Relocate::tls_gd_to_le(const Relocate_info<64, false>* relinfo,
2224                                       size_t relnum,
2225                                       Output_segment* tls_segment,
2226                                       const elfcpp::Rela<64, false>& rela,
2227                                       unsigned int,
2228                                       elfcpp::Elf_types<64>::Elf_Addr value,
2229                                       unsigned char* view,
2230                                       section_size_type view_size)
2231 {
2232   // .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
2233   // .word 0x6666; rex64; call __tls_get_addr
2234   // ==> movq %fs:0,%rax; leaq x@tpoff(%rax),%rax
2235
2236   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -4);
2237   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 12);
2238
2239   tls::check_tls(relinfo, relnum, rela.get_r_offset(),
2240                  (memcmp(view - 4, "\x66\x48\x8d\x3d", 4) == 0));
2241   tls::check_tls(relinfo, relnum, rela.get_r_offset(),
2242                  (memcmp(view + 4, "\x66\x66\x48\xe8", 4) == 0));
2243
2244   memcpy(view - 4, "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0\0", 16);
2245
2246   value -= tls_segment->memsz();
2247   Relocate_functions<64, false>::rela32(view + 8, value, 0);
2248
2249   // The next reloc should be a PLT32 reloc against __tls_get_addr.
2250   // We can skip it.
2251   this->skip_call_tls_get_addr_ = true;
2252 }
2253
2254 // Do a TLSDESC-style General-Dynamic to Initial-Exec transition.
2255
2256 inline void
2257 Target_x86_64::Relocate::tls_desc_gd_to_ie(
2258     const Relocate_info<64, false>* relinfo,
2259     size_t relnum,
2260     Output_segment*,
2261     const elfcpp::Rela<64, false>& rela,
2262     unsigned int r_type,
2263     elfcpp::Elf_types<64>::Elf_Addr value,
2264     unsigned char* view,
2265     elfcpp::Elf_types<64>::Elf_Addr address,
2266     section_size_type view_size)
2267 {
2268   if (r_type == elfcpp::R_X86_64_GOTPC32_TLSDESC)
2269     {
2270       // leaq foo@tlsdesc(%rip), %rax
2271       // ==> movq foo@gottpoff(%rip), %rax
2272       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -3);
2273       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 4);
2274       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
2275                      view[-3] == 0x48 && view[-2] == 0x8d && view[-1] == 0x05);
2276       view[-2] = 0x8b;
2277       const elfcpp::Elf_Xword addend = rela.get_r_addend();
2278       Relocate_functions<64, false>::pcrela32(view, value, addend, address);
2279     }
2280   else
2281     {
2282       // call *foo@tlscall(%rax)
2283       // ==> nop; nop
2284       gold_assert(r_type == elfcpp::R_X86_64_TLSDESC_CALL);
2285       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 2);
2286       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
2287                      view[0] == 0xff && view[1] == 0x10);
2288       view[0] = 0x66;
2289       view[1] = 0x90;
2290     }
2291 }
2292
2293 // Do a TLSDESC-style General-Dynamic to Local-Exec transition.
2294
2295 inline void
2296 Target_x86_64::Relocate::tls_desc_gd_to_le(
2297     const Relocate_info<64, false>* relinfo,
2298     size_t relnum,
2299     Output_segment* tls_segment,
2300     const elfcpp::Rela<64, false>& rela,
2301     unsigned int r_type,
2302     elfcpp::Elf_types<64>::Elf_Addr value,
2303     unsigned char* view,
2304     section_size_type view_size)
2305 {
2306   if (r_type == elfcpp::R_X86_64_GOTPC32_TLSDESC)
2307     {
2308       // leaq foo@tlsdesc(%rip), %rax
2309       // ==> movq foo@tpoff, %rax
2310       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -3);
2311       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 4);
2312       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
2313                      view[-3] == 0x48 && view[-2] == 0x8d && view[-1] == 0x05);
2314       view[-2] = 0xc7;
2315       view[-1] = 0xc0;
2316       value -= tls_segment->memsz();
2317       Relocate_functions<64, false>::rela32(view, value, 0);
2318     }
2319   else
2320     {
2321       // call *foo@tlscall(%rax)
2322       // ==> nop; nop
2323       gold_assert(r_type == elfcpp::R_X86_64_TLSDESC_CALL);
2324       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 2);
2325       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
2326                      view[0] == 0xff && view[1] == 0x10);
2327       view[0] = 0x66;
2328       view[1] = 0x90;
2329     }
2330 }
2331
2332 inline void
2333 Target_x86_64::Relocate::tls_ld_to_le(const Relocate_info<64, false>* relinfo,
2334                                       size_t relnum,
2335                                       Output_segment*,
2336                                       const elfcpp::Rela<64, false>& rela,
2337                                       unsigned int,
2338                                       elfcpp::Elf_types<64>::Elf_Addr,
2339                                       unsigned char* view,
2340                                       section_size_type view_size)
2341 {
2342   // leaq foo@tlsld(%rip),%rdi; call __tls_get_addr@plt;
2343   // ... leq foo@dtpoff(%rax),%reg
2344   // ==> .word 0x6666; .byte 0x66; movq %fs:0,%rax ... leaq x@tpoff(%rax),%rdx
2345
2346   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -3);
2347   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 9);
2348
2349   tls::check_tls(relinfo, relnum, rela.get_r_offset(),
2350                  view[-3] == 0x48 && view[-2] == 0x8d && view[-1] == 0x3d);
2351
2352   tls::check_tls(relinfo, relnum, rela.get_r_offset(), view[4] == 0xe8);
2353
2354   memcpy(view - 3, "\x66\x66\x66\x64\x48\x8b\x04\x25\0\0\0\0", 12);
2355
2356   // The next reloc should be a PLT32 reloc against __tls_get_addr.
2357   // We can skip it.
2358   this->skip_call_tls_get_addr_ = true;
2359 }
2360
2361 // Do a relocation in which we convert a TLS Initial-Exec to a
2362 // Local-Exec.
2363
2364 inline void
2365 Target_x86_64::Relocate::tls_ie_to_le(const Relocate_info<64, false>* relinfo,
2366                                       size_t relnum,
2367                                       Output_segment* tls_segment,
2368                                       const elfcpp::Rela<64, false>& rela,
2369                                       unsigned int,
2370                                       elfcpp::Elf_types<64>::Elf_Addr value,
2371                                       unsigned char* view,
2372                                       section_size_type view_size)
2373 {
2374   // We need to examine the opcodes to figure out which instruction we
2375   // are looking at.
2376
2377   // movq foo@gottpoff(%rip),%reg  ==>  movq $YY,%reg
2378   // addq foo@gottpoff(%rip),%reg  ==>  addq $YY,%reg
2379
2380   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -3);
2381   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 4);
2382
2383   unsigned char op1 = view[-3];
2384   unsigned char op2 = view[-2];
2385   unsigned char op3 = view[-1];
2386   unsigned char reg = op3 >> 3;
2387
2388   if (op2 == 0x8b)
2389     {
2390       // movq
2391       if (op1 == 0x4c)
2392         view[-3] = 0x49;
2393       view[-2] = 0xc7;
2394       view[-1] = 0xc0 | reg;
2395     }
2396   else if (reg == 4)
2397     {
2398       // Special handling for %rsp.
2399       if (op1 == 0x4c)
2400         view[-3] = 0x49;
2401       view[-2] = 0x81;
2402       view[-1] = 0xc0 | reg;
2403     }
2404   else
2405     {
2406       // addq
2407       if (op1 == 0x4c)
2408         view[-3] = 0x4d;
2409       view[-2] = 0x8d;
2410       view[-1] = 0x80 | reg | (reg << 3);
2411     }
2412
2413   value -= tls_segment->memsz();
2414   Relocate_functions<64, false>::rela32(view, value, 0);
2415 }
2416
2417 // Relocate section data.
2418
2419 void
2420 Target_x86_64::relocate_section(const Relocate_info<64, false>* relinfo,
2421                                 unsigned int sh_type,
2422                                 const unsigned char* prelocs,
2423                                 size_t reloc_count,
2424                                 Output_section* output_section,
2425                                 bool needs_special_offset_handling,
2426                                 unsigned char* view,
2427                                 elfcpp::Elf_types<64>::Elf_Addr address,
2428                                 section_size_type view_size)
2429 {
2430   gold_assert(sh_type == elfcpp::SHT_RELA);
2431
2432   gold::relocate_section<64, false, Target_x86_64, elfcpp::SHT_RELA,
2433                          Target_x86_64::Relocate>(
2434     relinfo,
2435     this,
2436     prelocs,
2437     reloc_count,
2438     output_section,
2439     needs_special_offset_handling,
2440     view,
2441     address,
2442     view_size);
2443 }
2444
2445 // Return the size of a relocation while scanning during a relocatable
2446 // link.
2447
2448 unsigned int
2449 Target_x86_64::Relocatable_size_for_reloc::get_size_for_reloc(
2450     unsigned int r_type,
2451     Relobj* object)
2452 {
2453   switch (r_type)
2454     {
2455     case elfcpp::R_X86_64_NONE:
2456     case elfcpp::R_386_GNU_VTINHERIT:
2457     case elfcpp::R_386_GNU_VTENTRY:
2458     case elfcpp::R_X86_64_TLSGD:            // Global-dynamic
2459     case elfcpp::R_X86_64_GOTPC32_TLSDESC:  // Global-dynamic (from ~oliva url)
2460     case elfcpp::R_X86_64_TLSDESC_CALL:
2461     case elfcpp::R_X86_64_TLSLD:            // Local-dynamic
2462     case elfcpp::R_X86_64_DTPOFF32:
2463     case elfcpp::R_X86_64_DTPOFF64:
2464     case elfcpp::R_X86_64_GOTTPOFF:         // Initial-exec
2465     case elfcpp::R_X86_64_TPOFF32:          // Local-exec
2466       return 0;
2467
2468     case elfcpp::R_X86_64_64:
2469     case elfcpp::R_X86_64_PC64:
2470     case elfcpp::R_X86_64_GOTOFF64:
2471     case elfcpp::R_X86_64_GOTPC64:
2472     case elfcpp::R_X86_64_PLTOFF64:
2473     case elfcpp::R_X86_64_GOT64:
2474     case elfcpp::R_X86_64_GOTPCREL64:
2475     case elfcpp::R_X86_64_GOTPCREL:
2476     case elfcpp::R_X86_64_GOTPLT64:
2477       return 8;
2478
2479     case elfcpp::R_X86_64_32:
2480     case elfcpp::R_X86_64_32S:
2481     case elfcpp::R_X86_64_PC32:
2482     case elfcpp::R_X86_64_PLT32:
2483     case elfcpp::R_X86_64_GOTPC32:
2484     case elfcpp::R_X86_64_GOT32:
2485       return 4;
2486
2487     case elfcpp::R_X86_64_16:
2488     case elfcpp::R_X86_64_PC16:
2489       return 2;
2490
2491     case elfcpp::R_X86_64_8:
2492     case elfcpp::R_X86_64_PC8:
2493       return 1;
2494
2495     case elfcpp::R_X86_64_COPY:
2496     case elfcpp::R_X86_64_GLOB_DAT:
2497     case elfcpp::R_X86_64_JUMP_SLOT:
2498     case elfcpp::R_X86_64_RELATIVE:
2499       // These are outstanding tls relocs, which are unexpected when linking
2500     case elfcpp::R_X86_64_TPOFF64:
2501     case elfcpp::R_X86_64_DTPMOD64:
2502     case elfcpp::R_X86_64_TLSDESC:
2503       object->error(_("unexpected reloc %u in object file"), r_type);
2504       return 0;
2505
2506     case elfcpp::R_X86_64_SIZE32:
2507     case elfcpp::R_X86_64_SIZE64:
2508     default:
2509       object->error(_("unsupported reloc %u against local symbol"), r_type);
2510       return 0;
2511     }
2512 }
2513
2514 // Scan the relocs during a relocatable link.
2515
2516 void
2517 Target_x86_64::scan_relocatable_relocs(const General_options& options,
2518                                        Symbol_table* symtab,
2519                                        Layout* layout,
2520                                        Sized_relobj<64, false>* object,
2521                                        unsigned int data_shndx,
2522                                        unsigned int sh_type,
2523                                        const unsigned char* prelocs,
2524                                        size_t reloc_count,
2525                                        Output_section* output_section,
2526                                        bool needs_special_offset_handling,
2527                                        size_t local_symbol_count,
2528                                        const unsigned char* plocal_symbols,
2529                                        Relocatable_relocs* rr)
2530 {
2531   gold_assert(sh_type == elfcpp::SHT_RELA);
2532
2533   typedef gold::Default_scan_relocatable_relocs<elfcpp::SHT_RELA,
2534     Relocatable_size_for_reloc> Scan_relocatable_relocs;
2535
2536   gold::scan_relocatable_relocs<64, false, elfcpp::SHT_RELA,
2537       Scan_relocatable_relocs>(
2538     options,
2539     symtab,
2540     layout,
2541     object,
2542     data_shndx,
2543     prelocs,
2544     reloc_count,
2545     output_section,
2546     needs_special_offset_handling,
2547     local_symbol_count,
2548     plocal_symbols,
2549     rr);
2550 }
2551
2552 // Relocate a section during a relocatable link.
2553
2554 void
2555 Target_x86_64::relocate_for_relocatable(
2556     const Relocate_info<64, false>* relinfo,
2557     unsigned int sh_type,
2558     const unsigned char* prelocs,
2559     size_t reloc_count,
2560     Output_section* output_section,
2561     off_t offset_in_output_section,
2562     const Relocatable_relocs* rr,
2563     unsigned char* view,
2564     elfcpp::Elf_types<64>::Elf_Addr view_address,
2565     section_size_type view_size,
2566     unsigned char* reloc_view,
2567     section_size_type reloc_view_size)
2568 {
2569   gold_assert(sh_type == elfcpp::SHT_RELA);
2570
2571   gold::relocate_for_relocatable<64, false, elfcpp::SHT_RELA>(
2572     relinfo,
2573     prelocs,
2574     reloc_count,
2575     output_section,
2576     offset_in_output_section,
2577     rr,
2578     view,
2579     view_address,
2580     view_size,
2581     reloc_view,
2582     reloc_view_size);
2583 }
2584
2585 // Return the value to use for a dynamic which requires special
2586 // treatment.  This is how we support equality comparisons of function
2587 // pointers across shared library boundaries, as described in the
2588 // processor specific ABI supplement.
2589
2590 uint64_t
2591 Target_x86_64::do_dynsym_value(const Symbol* gsym) const
2592 {
2593   gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset());
2594   return this->plt_section()->address() + gsym->plt_offset();
2595 }
2596
2597 // Return a string used to fill a code section with nops to take up
2598 // the specified length.
2599
2600 std::string
2601 Target_x86_64::do_code_fill(section_size_type length) const
2602 {
2603   if (length >= 16)
2604     {
2605       // Build a jmpq instruction to skip over the bytes.
2606       unsigned char jmp[5];
2607       jmp[0] = 0xe9;
2608       elfcpp::Swap_unaligned<32, false>::writeval(jmp + 1, length - 5);
2609       return (std::string(reinterpret_cast<char*>(&jmp[0]), 5)
2610               + std::string(length - 5, '\0'));
2611     }
2612
2613   // Nop sequences of various lengths.
2614   const char nop1[1] = { 0x90 };                   // nop
2615   const char nop2[2] = { 0x66, 0x90 };             // xchg %ax %ax
2616   const char nop3[3] = { 0x0f, 0x1f, 0x00 };       // nop (%rax)
2617   const char nop4[4] = { 0x0f, 0x1f, 0x40, 0x00};  // nop 0(%rax)
2618   const char nop5[5] = { 0x0f, 0x1f, 0x44, 0x00,   // nop 0(%rax,%rax,1)
2619                          0x00 };
2620   const char nop6[6] = { 0x66, 0x0f, 0x1f, 0x44,   // nopw 0(%rax,%rax,1)
2621                          0x00, 0x00 };
2622   const char nop7[7] = { 0x0f, 0x1f, 0x80, 0x00,   // nopl 0L(%rax)
2623                          0x00, 0x00, 0x00 };
2624   const char nop8[8] = { 0x0f, 0x1f, 0x84, 0x00,   // nopl 0L(%rax,%rax,1)
2625                          0x00, 0x00, 0x00, 0x00 };
2626   const char nop9[9] = { 0x66, 0x0f, 0x1f, 0x84,   // nopw 0L(%rax,%rax,1)
2627                          0x00, 0x00, 0x00, 0x00,
2628                          0x00 };
2629   const char nop10[10] = { 0x66, 0x2e, 0x0f, 0x1f, // nopw %cs:0L(%rax,%rax,1)
2630                            0x84, 0x00, 0x00, 0x00,
2631                            0x00, 0x00 };
2632   const char nop11[11] = { 0x66, 0x66, 0x2e, 0x0f, // data16
2633                            0x1f, 0x84, 0x00, 0x00, // nopw %cs:0L(%rax,%rax,1)
2634                            0x00, 0x00, 0x00 };
2635   const char nop12[12] = { 0x66, 0x66, 0x66, 0x2e, // data16; data16
2636                            0x0f, 0x1f, 0x84, 0x00, // nopw %cs:0L(%rax,%rax,1)
2637                            0x00, 0x00, 0x00, 0x00 };
2638   const char nop13[13] = { 0x66, 0x66, 0x66, 0x66, // data16; data16; data16
2639                            0x2e, 0x0f, 0x1f, 0x84, // nopw %cs:0L(%rax,%rax,1)
2640                            0x00, 0x00, 0x00, 0x00,
2641                            0x00 };
2642   const char nop14[14] = { 0x66, 0x66, 0x66, 0x66, // data16; data16; data16
2643                            0x66, 0x2e, 0x0f, 0x1f, // data16
2644                            0x84, 0x00, 0x00, 0x00, // nopw %cs:0L(%rax,%rax,1)
2645                            0x00, 0x00 };
2646   const char nop15[15] = { 0x66, 0x66, 0x66, 0x66, // data16; data16; data16
2647                            0x66, 0x66, 0x2e, 0x0f, // data16; data16
2648                            0x1f, 0x84, 0x00, 0x00, // nopw %cs:0L(%rax,%rax,1)
2649                            0x00, 0x00, 0x00 };
2650
2651   const char* nops[16] = {
2652     NULL,
2653     nop1, nop2, nop3, nop4, nop5, nop6, nop7,
2654     nop8, nop9, nop10, nop11, nop12, nop13, nop14, nop15
2655   };
2656
2657   return std::string(nops[length], length);
2658 }
2659
2660 // The selector for x86_64 object files.
2661
2662 class Target_selector_x86_64 : public Target_selector_freebsd
2663 {
2664 public:
2665   Target_selector_x86_64()
2666     : Target_selector_freebsd(elfcpp::EM_X86_64, 64, false, "elf64-x86-64",
2667                               "elf64-x86-64-freebsd")
2668   { }
2669
2670   Target*
2671   do_instantiate_target()
2672   { return new Target_x86_64(); }
2673
2674 };
2675
2676 Target_selector_x86_64 target_selector_x86_64;
2677
2678 } // End anonymous namespace.