gold/i386.cc

   1 // i386.cc -- i386 target support for gold.
   2
   3 #include "gold.h"
   4
   5 #include <cstring>
   6
   7 #include "elfcpp.h"
   8 #include "reloc.h"
   9 #include "i386.h"
  10 #include "object.h"
  11 #include "symtab.h"
  12 #include "layout.h"
  13 #include "output.h"
  14 #include "target.h"
  15 #include "target-reloc.h"
  16 #include "target-select.h"
  17
  18 namespace
  19 {
  20
  21 using namespace gold;
  22
  23 class Output_data_plt_i386;
  24
  25 // The i386 target class.
  26
  27 class Target_i386 : public Sized_target<32, false>
  28 {
  29  public:
  30   typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, false> Reloc_section;
  31
  32   Target_i386()
  33     : Sized_target<32, false>(&i386_info),
  34       got_(NULL), plt_(NULL), got_plt_(NULL), rel_dyn_(NULL),
  35       copy_relocs_(NULL), dynbss_(NULL)
  36   { }
  37
  38   // Scan the relocations to look for symbol adjustments.
  39   void
  40   scan_relocs(const General_options& options,
  41               Symbol_table* symtab,
  42               Layout* layout,
  43               Sized_relobj<32, false>* object,
  44               unsigned int data_shndx,
  45               unsigned int sh_type,
  46               const unsigned char* prelocs,
  47               size_t reloc_count,
  48               size_t local_symbol_count,
  49               const unsigned char* plocal_symbols,
  50               Symbol** global_symbols);
  51
  52   // Finalize the sections.
  53   void
  54   do_finalize_sections(const General_options*, Layout*);
  55
  56   // Relocate a section.
  57   void
  58   relocate_section(const Relocate_info<32, false>*,
  59                    unsigned int sh_type,
  60                    const unsigned char* prelocs,
  61                    size_t reloc_count,
  62                    unsigned char* view,
  63                    elfcpp::Elf_types<32>::Elf_Addr view_address,
  64                    off_t view_size);
  65
  66  private:
  67   // The class which scans relocations.
  68   struct Scan
  69   {
  70     inline void
  71     local(const General_options& options, Symbol_table* symtab,
  72           Layout* layout, Target_i386* target,
  73           Sized_relobj<32, false>* object,
  74           unsigned int data_shndx,
  75           const elfcpp::Rel<32, false>& reloc, unsigned int r_type,
  76           const elfcpp::Sym<32, false>& lsym);
  77
  78     inline void
  79     global(const General_options& options, Symbol_table* symtab,
  80            Layout* layout, Target_i386* target,
  81            Sized_relobj<32, false>* object,
  82            unsigned int data_shndx,
  83            const elfcpp::Rel<32, false>& reloc, unsigned int r_type,
  84            Symbol* gsym);
  85   };
  86
  87   // The class which implements relocation.
  88   class Relocate
  89   {
  90    public:
  91     Relocate()
  92       : skip_call_tls_get_addr_(false)
  93     { }
  94
  95     ~Relocate()
  96     {
  97       if (this->skip_call_tls_get_addr_)
  98         {
  99           // FIXME: This needs to specify the location somehow.
 100           fprintf(stderr, _("%s: missing expected TLS relocation\n"),
 101                   program_name);
 102           gold_exit(false);
 103         }
 104     }
 105
 106     // Do a relocation.  Return false if the caller should not issue
 107     // any warnings about this relocation.
 108     inline bool
 109     relocate(const Relocate_info<32, false>*, Target_i386*, size_t relnum,
 110              const elfcpp::Rel<32, false>&,
 111              unsigned int r_type, const Sized_symbol<32>*,
 112              const Symbol_value<32>*,
 113              unsigned char*, elfcpp::Elf_types<32>::Elf_Addr,
 114              off_t);
 115
 116    private:
 117     // Do a TLS relocation.
 118     inline void
 119     relocate_tls(const Relocate_info<32, false>*, size_t relnum,
 120                  const elfcpp::Rel<32, false>&,
 121                  unsigned int r_type, const Sized_symbol<32>*,
 122                  const Symbol_value<32>*,
 123                  unsigned char*, elfcpp::Elf_types<32>::Elf_Addr, off_t);
 124
 125     // Do a TLS Initial-Exec to Local-Exec transition.
 126     static inline void
 127     tls_ie_to_le(const Relocate_info<32, false>*, size_t relnum,
 128                  Output_segment* tls_segment,
 129                  const elfcpp::Rel<32, false>&, unsigned int r_type,
 130                  elfcpp::Elf_types<32>::Elf_Addr value,
 131                  unsigned char* view,
 132                  off_t view_size);
 133
 134     // Do a TLS Global-Dynamic to Local-Exec transition.
 135     inline void
 136     tls_gd_to_le(const Relocate_info<32, false>*, size_t relnum,
 137                  Output_segment* tls_segment,
 138                  const elfcpp::Rel<32, false>&, unsigned int r_type,
 139                  elfcpp::Elf_types<32>::Elf_Addr value,
 140                  unsigned char* view,
 141                  off_t view_size);
 142
 143     // Check the range for a TLS relocation.
 144     static inline void
 145     check_range(const Relocate_info<32, false>*, size_t relnum,
 146                 const elfcpp::Rel<32, false>&, off_t, off_t);
 147
 148     // Check the validity of a TLS relocation.  This is like assert.
 149     static inline void
 150     check_tls(const Relocate_info<32, false>*, size_t relnum,
 151               const elfcpp::Rel<32, false>&, bool);
 152
 153     // This is set if we should skip the next reloc, which should be a
 154     // PLT32 reloc against ___tls_get_addr.
 155     bool skip_call_tls_get_addr_;
 156   };
 157
 158   // Adjust TLS relocation type based on the options and whether this
 159   // is a local symbol.
 160   static unsigned int
 161   optimize_tls_reloc(const General_options*, bool is_final, int r_type);
 162
 163   // Get the GOT section, creating it if necessary.
 164   Output_data_got<32, false>*
 165   got_section(const General_options*, Symbol_table*, Layout*);
 166
 167   // Create a PLT entry for a global symbol.
 168   void
 169   make_plt_entry(const General_options* options, Symbol_table*,
 170                  Layout*, Symbol*);
 171
 172   // Get the PLT section.
 173   Output_data_plt_i386*
 174   plt_section() const
 175   {
 176     gold_assert(this->plt_ != NULL);
 177     return this->plt_;
 178   }
 179
 180   // Get the dynamic reloc section, creating it if necessary.
 181   Reloc_section*
 182   rel_dyn_section(Layout*);
 183
 184   // Copy a relocation against a global symbol.
 185   void
 186   copy_reloc(const General_options*, Symbol_table*, Layout*,
 187              Sized_relobj<32, false>*, unsigned int,
 188              Symbol*, const elfcpp::Rel<32, false>&);
 189
 190   // Information about this specific target which we pass to the
 191   // general Target structure.
 192   static const Target::Target_info i386_info;
 193
 194   // The GOT section.
 195   Output_data_got<32, false>* got_;
 196   // The PLT section.
 197   Output_data_plt_i386* plt_;
 198   // The GOT PLT section.
 199   Output_data_space* got_plt_;
 200   // The dynamic reloc section.
 201   Reloc_section* rel_dyn_;
 202   // Relocs saved to avoid a COPY reloc.
 203   Copy_relocs<32, false>* copy_relocs_;
 204   // Space for variables copied with a COPY reloc.
 205   Output_data_space* dynbss_;
 206 };
 207
 208 const Target::Target_info Target_i386::i386_info =
 209 {
 210   32,                   // size
 211   false,                // is_big_endian
 212   elfcpp::EM_386,       // machine_code
 213   false,                // has_make_symbol
 214   false,                // has_resolve
 215   "/usr/lib/libc.so.1", // dynamic_linker
 216   0x08048000,           // text_segment_address
 217   0x1000,               // abi_pagesize
 218   0x1000                // common_pagesize
 219 };
 220
 221 // Get the GOT section, creating it if necessary.
 222
 223 Output_data_got<32, false>*
 224 Target_i386::got_section(const General_options* options, Symbol_table* symtab,
 225                          Layout* layout)
 226 {
 227   if (this->got_ == NULL)
 228     {
 229       gold_assert(options != NULL && symtab != NULL && layout != NULL);
 230
 231       this->got_ = new Output_data_got<32, false>(options);
 232
 233       layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
 234                                       elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE,
 235                                       this->got_);
 236
 237       // The old GNU linker creates a .got.plt section.  We just
 238       // create another set of data in the .got section.  Note that we
 239       // always create a PLT if we create a GOT, although the PLT
 240       // might be empty.
 241       this->got_plt_ = new Output_data_space(4);
 242       layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
 243                                       elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE,
 244                                       this->got_plt_);
 245
 246       // The first three entries are reserved.
 247       this->got_plt_->set_space_size(3 * 4);
 248
 249       // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
 250       symtab->define_in_output_data(this, "_GLOBAL_OFFSET_TABLE_", NULL,
 251                                     this->got_plt_,
 252                                     0, 0, elfcpp::STT_OBJECT,
 253                                     elfcpp::STB_LOCAL,
 254                                     elfcpp::STV_HIDDEN, 0,
 255                                     false, false);
 256     }
 257
 258   return this->got_;
 259 }
 260
 261 // Get the dynamic reloc section, creating it if necessary.
 262
 263 Target_i386::Reloc_section*
 264 Target_i386::rel_dyn_section(Layout* layout)
 265 {
 266   if (this->rel_dyn_ == NULL)
 267     {
 268       gold_assert(layout != NULL);
 269       this->rel_dyn_ = new Reloc_section();
 270       layout->add_output_section_data(".rel.dyn", elfcpp::SHT_REL,
 271                                       elfcpp::SHF_ALLOC, this->rel_dyn_);
 272     }
 273   return this->rel_dyn_;
 274 }
 275
 276 // A class to handle the PLT data.
 277
 278 class Output_data_plt_i386 : public Output_section_data
 279 {
 280  public:
 281   typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, false> Reloc_section;
 282
 283   Output_data_plt_i386(Layout*, Output_data_space*, bool is_shared);
 284
 285   // Add an entry to the PLT.
 286   void
 287   add_entry(Symbol* gsym);
 288
 289   // Return the .rel.plt section data.
 290   const Reloc_section*
 291   rel_plt() const
 292   { return this->rel_; }
 293
 294  protected:
 295   void
 296   do_adjust_output_section(Output_section* os);
 297
 298  private:
 299   // The size of an entry in the PLT.
 300   static const int plt_entry_size = 16;
 301
 302   // The first entry in the PLT for an executable.
 303   static unsigned char exec_first_plt_entry[plt_entry_size];
 304
 305   // The first entry in the PLT for a shared object.
 306   static unsigned char dyn_first_plt_entry[plt_entry_size];
 307
 308   // Other entries in the PLT for an executable.
 309   static unsigned char exec_plt_entry[plt_entry_size];
 310
 311   // Other entries in the PLT for a shared object.
 312   static unsigned char dyn_plt_entry[plt_entry_size];
 313
 314   // Set the final size.
 315   void
 316   do_set_address(uint64_t, off_t)
 317   { this->set_data_size((this->count_ + 1) * plt_entry_size); }
 318
 319   // Write out the PLT data.
 320   void
 321   do_write(Output_file*);
 322
 323   // The reloc section.
 324   Reloc_section* rel_;
 325   // The .got.plt section.
 326   Output_data_space* got_plt_;
 327   // The number of PLT entries.
 328   unsigned int count_;
 329   // Whether we are generated a shared object.
 330   bool is_shared_;
 331 };
 332
 333 // Create the PLT section.  The ordinary .got section is an argument,
 334 // since we need to refer to the start.  We also create our own .got
 335 // section just for PLT entries.
 336
 337 Output_data_plt_i386::Output_data_plt_i386(Layout* layout,
 338                                            Output_data_space* got_plt,
 339                                            bool is_shared)
 340   : Output_section_data(4), got_plt_(got_plt), is_shared_(is_shared)
 341 {
 342   this->rel_ = new Reloc_section();
 343   layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL,
 344                                   elfcpp::SHF_ALLOC, this->rel_);
 345 }
 346
 347 // For some reason
 348
 349 void
 350 Output_data_plt_i386::do_adjust_output_section(Output_section* os)
 351 {
 352   // UnixWare sets the entsize of .plt to 4, and so does the old GNU
 353   // linker, and so do we.
 354   os->set_entsize(4);
 355 }
 356
 357 // Add an entry to the PLT.
 358
 359 void
 360 Output_data_plt_i386::add_entry(Symbol* gsym)
 361 {
 362   gold_assert(!gsym->has_plt_offset());
 363
 364   // Note that when setting the PLT offset we skip the initial
 365   // reserved PLT entry.
 366   gsym->set_plt_offset((this->count_ + 1) * plt_entry_size);
 367
 368   ++this->count_;
 369
 370   off_t got_offset = this->got_plt_->data_size();
 371
 372   // Every PLT entry needs a GOT entry which points back to the PLT
 373   // entry (this will be changed by the dynamic linker, normally
 374   // lazily when the function is called).
 375   this->got_plt_->set_space_size(got_offset + 4);
 376
 377   // Every PLT entry needs a reloc.
 378   gsym->set_needs_dynsym_entry();
 379   this->rel_->add_global(gsym, elfcpp::R_386_JUMP_SLOT, this->got_plt_,
 380                          got_offset);
 381
 382   // Note that we don't need to save the symbol.  The contents of the
 383   // PLT are independent of which symbols are used.  The symbols only
 384   // appear in the relocations.
 385 }
 386
 387 // The first entry in the PLT for an executable.
 388
 389 unsigned char Output_data_plt_i386::exec_first_plt_entry[plt_entry_size] =
 390 {
 391   0xff, 0x35,   // pushl contents of memory address
 392   0, 0, 0, 0,   // replaced with address of .got + 4
 393   0xff, 0x25,   // jmp indirect
 394   0, 0, 0, 0,   // replaced with address of .got + 8
 395   0, 0, 0, 0    // unused
 396 };
 397
 398 // The first entry in the PLT for a shared object.
 399
 400 unsigned char Output_data_plt_i386::dyn_first_plt_entry[plt_entry_size] =
 401 {
 402   0xff, 0xb3, 4, 0, 0, 0,       // pushl 4(%ebx)
 403   0xff, 0xa3, 8, 0, 0, 0,       // jmp *8(%ebx)
 404   0, 0, 0, 0                    // unused
 405 };
 406
 407 // Subsequent entries in the PLT for an executable.
 408
 409 unsigned char Output_data_plt_i386::exec_plt_entry[plt_entry_size] =
 410 {
 411   0xff, 0x25,   // jmp indirect
 412   0, 0, 0, 0,   // replaced with address of symbol in .got
 413   0x68,         // pushl immediate
 414   0, 0, 0, 0,   // replaced with offset into relocation table
 415   0xe9,         // jmp relative
 416   0, 0, 0, 0    // replaced with offset to start of .plt
 417 };
 418
 419 // Subsequent entries in the PLT for a shared object.
 420
 421 unsigned char Output_data_plt_i386::dyn_plt_entry[plt_entry_size] =
 422 {
 423   0xff, 0xa3,   // jmp *offset(%ebx)
 424   0, 0, 0, 0,   // replaced with offset of symbol in .got
 425   0x68,         // pushl immediate
 426   0, 0, 0, 0,   // replaced with offset into relocation table
 427   0xe9,         // jmp relative
 428   0, 0, 0, 0    // replaced with offset to start of .plt
 429 };
 430
 431 // Write out the PLT.  This uses the hand-coded instructions above,
 432 // and adjusts them as needed.  This is all specified by the i386 ELF
 433 // Processor Supplement.
 434
 435 void
 436 Output_data_plt_i386::do_write(Output_file* of)
 437 {
 438   const off_t offset = this->offset();
 439   const off_t oview_size = this->data_size();
 440   unsigned char* const oview = of->get_output_view(offset, oview_size);
 441
 442   const off_t got_file_offset = this->got_plt_->offset();
 443   const off_t got_size = this->got_plt_->data_size();
 444   unsigned char* const got_view = of->get_output_view(got_file_offset,
 445                                                       got_size);
 446
 447   unsigned char* pov = oview;
 448
 449   elfcpp::Elf_types<32>::Elf_Addr plt_address = this->address();
 450   elfcpp::Elf_types<32>::Elf_Addr got_address = this->got_plt_->address();
 451
 452   if (this->is_shared_)
 453     memcpy(pov, dyn_first_plt_entry, plt_entry_size);
 454   else
 455     {
 456       memcpy(pov, exec_first_plt_entry, plt_entry_size);
 457       elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_address + 4);
 458       elfcpp::Swap<32, false>::writeval(pov + 8, got_address + 8);
 459     }
 460   pov += plt_entry_size;
 461
 462   unsigned char* got_pov = got_view;
 463
 464   memset(got_pov, 0, 12);
 465   got_pov += 12;
 466
 467   const int rel_size = elfcpp::Elf_sizes<32>::rel_size;
 468
 469   unsigned int plt_offset = plt_entry_size;
 470   unsigned int plt_rel_offset = 0;
 471   unsigned int got_offset = 12;
 472   const unsigned int count = this->count_;
 473   for (unsigned int i = 0;
 474        i < count;
 475        ++i,
 476          pov += plt_entry_size,
 477          got_pov += 4,
 478          plt_offset += plt_entry_size,
 479          plt_rel_offset += rel_size,
 480          got_offset += 4)
 481     {
 482       // Set and adjust the PLT entry itself.
 483
 484       if (this->is_shared_)
 485         {
 486           memcpy(pov, dyn_plt_entry, plt_entry_size);
 487           elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_offset);
 488         }
 489       else
 490         {
 491           memcpy(pov, exec_plt_entry, plt_entry_size);
 492           elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
 493                                                       (got_address
 494                                                        + got_offset));
 495         }
 496
 497       elfcpp::Swap_unaligned<32, false>::writeval(pov + 7, plt_rel_offset);
 498       elfcpp::Swap<32, false>::writeval(pov + 12,
 499                                         - (plt_offset + plt_entry_size));
 500
 501       // Set the entry in the GOT.
 502       elfcpp::Swap<32, false>::writeval(got_pov, plt_address + plt_offset + 6);
 503     }
 504
 505   gold_assert(pov - oview == oview_size);
 506   gold_assert(got_pov - got_view == got_size);
 507
 508   of->write_output_view(offset, oview_size, oview);
 509   of->write_output_view(got_file_offset, got_size, got_view);
 510 }
 511
 512 // Create a PLT entry for a global symbol.
 513
 514 void
 515 Target_i386::make_plt_entry(const General_options* options,
 516                             Symbol_table* symtab, Layout* layout, Symbol* gsym)
 517 {
 518   if (gsym->has_plt_offset())
 519     return;
 520
 521   if (this->plt_ == NULL)
 522     {
 523       // Create the GOT sections first.
 524       this->got_section(options, symtab, layout);
 525
 526       this->plt_ = new Output_data_plt_i386(layout, this->got_plt_,
 527                                             options->is_shared());
 528       layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
 529                                       (elfcpp::SHF_ALLOC
 530                                        | elfcpp::SHF_EXECINSTR),
 531                                       this->plt_);
 532     }
 533
 534   this->plt_->add_entry(gsym);
 535 }
 536
 537 // Handle a relocation against a non-function symbol defined in a
 538 // dynamic object.  The traditional way to handle this is to generate
 539 // a COPY relocation to copy the variable at runtime from the shared
 540 // object into the executable's data segment.  However, this is
 541 // undesirable in general, as if the size of the object changes in the
 542 // dynamic object, the executable will no longer work correctly.  If
 543 // this relocation is in a writable section, then we can create a
 544 // dynamic reloc and the dynamic linker will resolve it to the correct
 545 // address at runtime.  However, we do not want do that if the
 546 // relocation is in a read-only section, as it would prevent the
 547 // readonly segment from being shared.  And if we have to eventually
 548 // generate a COPY reloc, then any dynamic relocations will be
 549 // useless.  So this means that if this is a writable section, we need
 550 // to save the relocation until we see whether we have to create a
 551 // COPY relocation for this symbol for any other relocation.
 552
 553 void
 554 Target_i386::copy_reloc(const General_options* options,
 555                         Symbol_table* symtab,
 556                         Layout* layout,
 557                         Sized_relobj<32, false>* object,
 558                         unsigned int data_shndx, Symbol* gsym,
 559                         const elfcpp::Rel<32, false>& rel)
 560 {
 561   Sized_symbol<32>* ssym;
 562   ssym = symtab->get_sized_symbol SELECT_SIZE_NAME(32) (gsym
 563                                                         SELECT_SIZE(32));
 564
 565   if (!Copy_relocs<32, false>::need_copy_reloc(options, object,
 566                                                data_shndx, ssym))
 567     {
 568       // So far we do not need a COPY reloc.  Save this relocation.
 569       // If it turns out that we never need a COPY reloc for this
 570       // symbol, then we will emit the relocation.
 571       if (this->copy_relocs_ == NULL)
 572         this->copy_relocs_ = new Copy_relocs<32, false>();
 573       this->copy_relocs_->save(ssym, object, data_shndx, rel);
 574     }
 575   else
 576     {
 577       // Allocate space for this symbol in the .bss section.
 578
 579       elfcpp::Elf_types<32>::Elf_WXword symsize = ssym->symsize();
 580
 581       // There is no defined way to determine the required alignment
 582       // of the symbol.  We pick the alignment based on the size.  We
 583       // set an arbitrary maximum of 256.
 584       unsigned int align;
 585       for (align = 1; align < 512; align <<= 1)
 586         if ((symsize & align) != 0)
 587           break;
 588
 589       if (this->dynbss_ == NULL)
 590         {
 591           this->dynbss_ = new Output_data_space(align);
 592           layout->add_output_section_data(".bss",
 593                                           elfcpp::SHT_NOBITS,
 594                                           (elfcpp::SHF_ALLOC
 595                                            | elfcpp::SHF_WRITE),
 596                                           this->dynbss_);
 597         }
 598
 599       Output_data_space* dynbss = this->dynbss_;
 600
 601       if (align > dynbss->addralign())
 602         dynbss->set_space_alignment(align);
 603
 604       off_t dynbss_size = dynbss->data_size();
 605       dynbss_size = align_address(dynbss_size, align);
 606       off_t offset = dynbss_size;
 607       dynbss->set_space_size(dynbss_size + symsize);
 608
 609       // Define the symbol in the .dynbss section.
 610       symtab->define_in_output_data(this, ssym->name(), ssym->version(),
 611                                     dynbss, offset, symsize, ssym->type(),
 612                                     ssym->binding(), ssym->visibility(),
 613                                     ssym->nonvis(), false, false);
 614
 615       // Add the COPY reloc.
 616       ssym->set_needs_dynsym_entry();
 617       Reloc_section* rel_dyn = this->rel_dyn_section(layout);
 618       rel_dyn->add_global(ssym, elfcpp::R_386_COPY, dynbss, offset);
 619     }
 620 }
 621
 622 // Optimize the TLS relocation type based on what we know about the
 623 // symbol.  IS_FINAL is true if the final address of this symbol is
 624 // known at link time.
 625
 626 unsigned int
 627 Target_i386::optimize_tls_reloc(const General_options* options,
 628                                 bool is_final,
 629                                 int r_type)
 630 {
 631   // If we are generating a shared library, then we can't do anything
 632   // in the linker.
 633   if (options->is_shared())
 634     return r_type;
 635
 636   switch (r_type)
 637     {
 638     case elfcpp::R_386_TLS_GD:
 639     case elfcpp::R_386_TLS_GOTDESC:
 640     case elfcpp::R_386_TLS_DESC_CALL:
 641       // These are Global-Dynamic which permits fully general TLS
 642       // access.  Since we know that we are generating an executable,
 643       // we can convert this to Initial-Exec.  If we also know that
 644       // this is a local symbol, we can further switch to Local-Exec.
 645       if (is_final)
 646         return elfcpp::R_386_TLS_LE_32;
 647       return elfcpp::R_386_TLS_IE_32;
 648
 649     case elfcpp::R_386_TLS_LDM:
 650       // This is Local-Dynamic, which refers to a local symbol in the
 651       // dynamic TLS block.  Since we know that we generating an
 652       // executable, we can switch to Local-Exec.
 653       return elfcpp::R_386_TLS_LE_32;
 654
 655     case elfcpp::R_386_TLS_LDO_32:
 656       // Another type of Local-Dynamic relocation.
 657       return elfcpp::R_386_TLS_LE;
 658
 659     case elfcpp::R_386_TLS_IE:
 660     case elfcpp::R_386_TLS_GOTIE:
 661     case elfcpp::R_386_TLS_IE_32:
 662       // These are Initial-Exec relocs which get the thread offset
 663       // from the GOT.  If we know that we are linking against the
 664       // local symbol, we can switch to Local-Exec, which links the
 665       // thread offset into the instruction.
 666       if (is_final)
 667         return elfcpp::R_386_TLS_LE_32;
 668       return r_type;
 669
 670     case elfcpp::R_386_TLS_LE:
 671     case elfcpp::R_386_TLS_LE_32:
 672       // When we already have Local-Exec, there is nothing further we
 673       // can do.
 674       return r_type;
 675
 676     default:
 677       gold_unreachable();
 678     }
 679 }
 680
 681 // Scan a relocation for a local symbol.
 682
 683 inline void
 684 Target_i386::Scan::local(const General_options& options,
 685                          Symbol_table* symtab,
 686                          Layout* layout,
 687                          Target_i386* target,
 688                          Sized_relobj<32, false>* object,
 689                          unsigned int,
 690                          const elfcpp::Rel<32, false>&,
 691                          unsigned int r_type,
 692                          const elfcpp::Sym<32, false>&)
 693 {
 694   switch (r_type)
 695     {
 696     case elfcpp::R_386_NONE:
 697     case elfcpp::R_386_GNU_VTINHERIT:
 698     case elfcpp::R_386_GNU_VTENTRY:
 699       break;
 700
 701     case elfcpp::R_386_32:
 702     case elfcpp::R_386_16:
 703     case elfcpp::R_386_8:
 704       // FIXME: If we are generating a shared object we need to copy
 705       // this relocation into the object.
 706       gold_assert(!options.is_shared());
 707       break;
 708
 709     case elfcpp::R_386_PC32:
 710     case elfcpp::R_386_PC16:
 711     case elfcpp::R_386_PC8:
 712       break;
 713
 714     case elfcpp::R_386_GOTOFF:
 715     case elfcpp::R_386_GOTPC:
 716       // We need a GOT section.
 717       target->got_section(&options, symtab, layout);
 718       break;
 719
 720     case elfcpp::R_386_COPY:
 721     case elfcpp::R_386_GLOB_DAT:
 722     case elfcpp::R_386_JUMP_SLOT:
 723     case elfcpp::R_386_RELATIVE:
 724     case elfcpp::R_386_TLS_TPOFF:
 725     case elfcpp::R_386_TLS_DTPMOD32:
 726     case elfcpp::R_386_TLS_DTPOFF32:
 727     case elfcpp::R_386_TLS_TPOFF32:
 728     case elfcpp::R_386_TLS_DESC:
 729       fprintf(stderr, _("%s: %s: unexpected reloc %u in object file\n"),
 730               program_name, object->name().c_str(), r_type);
 731       gold_exit(false);
 732       break;
 733
 734     case elfcpp::R_386_TLS_IE:
 735     case elfcpp::R_386_TLS_GOTIE:
 736     case elfcpp::R_386_TLS_LE:
 737     case elfcpp::R_386_TLS_GD:
 738     case elfcpp::R_386_TLS_LDM:
 739     case elfcpp::R_386_TLS_LDO_32:
 740     case elfcpp::R_386_TLS_IE_32:
 741     case elfcpp::R_386_TLS_LE_32:
 742     case elfcpp::R_386_TLS_GOTDESC:
 743     case elfcpp::R_386_TLS_DESC_CALL:
 744       r_type = Target_i386::optimize_tls_reloc(&options,
 745                                                !options.is_shared(),
 746                                                r_type);
 747       switch (r_type)
 748         {
 749         case elfcpp::R_386_TLS_LE:
 750         case elfcpp::R_386_TLS_LE_32:
 751           // FIXME: If generating a shared object, we need to copy
 752           // this relocation into the object.
 753           gold_assert(!options.is_shared());
 754           break;
 755
 756         case elfcpp::R_386_TLS_IE:
 757         case elfcpp::R_386_TLS_GOTIE:
 758         case elfcpp::R_386_TLS_GD:
 759         case elfcpp::R_386_TLS_LDM:
 760         case elfcpp::R_386_TLS_LDO_32:
 761         case elfcpp::R_386_TLS_IE_32:
 762         case elfcpp::R_386_TLS_GOTDESC:
 763         case elfcpp::R_386_TLS_DESC_CALL:
 764           fprintf(stderr,
 765                   _("%s: %s: unsupported reloc %u against local symbol\n"),
 766                   program_name, object->name().c_str(), r_type);
 767           break;
 768         }
 769       break;
 770
 771     case elfcpp::R_386_GOT32:
 772     case elfcpp::R_386_PLT32:
 773     case elfcpp::R_386_32PLT:
 774     case elfcpp::R_386_TLS_GD_32:
 775     case elfcpp::R_386_TLS_GD_PUSH:
 776     case elfcpp::R_386_TLS_GD_CALL:
 777     case elfcpp::R_386_TLS_GD_POP:
 778     case elfcpp::R_386_TLS_LDM_32:
 779     case elfcpp::R_386_TLS_LDM_PUSH:
 780     case elfcpp::R_386_TLS_LDM_CALL:
 781     case elfcpp::R_386_TLS_LDM_POP:
 782     case elfcpp::R_386_USED_BY_INTEL_200:
 783     default:
 784       fprintf(stderr, _("%s: %s: unsupported reloc %u against local symbol\n"),
 785               program_name, object->name().c_str(), r_type);
 786       break;
 787     }
 788 }
 789
 790 // Scan a relocation for a global symbol.
 791
 792 inline void
 793 Target_i386::Scan::global(const General_options& options,
 794                           Symbol_table* symtab,
 795                           Layout* layout,
 796                           Target_i386* target,
 797                           Sized_relobj<32, false>* object,
 798                           unsigned int data_shndx,
 799                           const elfcpp::Rel<32, false>& reloc,
 800                           unsigned int r_type,
 801                           Symbol* gsym)
 802 {
 803   switch (r_type)
 804     {
 805     case elfcpp::R_386_NONE:
 806     case elfcpp::R_386_GNU_VTINHERIT:
 807     case elfcpp::R_386_GNU_VTENTRY:
 808       break;
 809
 810     case elfcpp::R_386_32:
 811     case elfcpp::R_386_PC32:
 812     case elfcpp::R_386_16:
 813     case elfcpp::R_386_PC16:
 814     case elfcpp::R_386_8:
 815     case elfcpp::R_386_PC8:
 816       // FIXME: If we are generating a shared object we may need to
 817       // copy this relocation into the object.  If this symbol is
 818       // defined in a shared object, we may need to copy this
 819       // relocation in order to avoid a COPY relocation.
 820       gold_assert(!options.is_shared());
 821
 822       if (gsym->is_from_dynobj())
 823         {
 824           // This symbol is defined in a dynamic object.  If it is a
 825           // function, we make a PLT entry.  Otherwise we need to
 826           // either generate a COPY reloc or copy this reloc.
 827           if (gsym->type() == elfcpp::STT_FUNC)
 828             target->make_plt_entry(&options, symtab, layout, gsym);
 829           else
 830             target->copy_reloc(&options, symtab, layout, object, data_shndx,
 831                                gsym, reloc);
 832         }
 833
 834       break;
 835
 836     case elfcpp::R_386_GOT32:
 837       // The symbol requires a GOT entry.
 838       if (target->got_section(&options, symtab, layout)->add_global(gsym))
 839         {
 840           // If this symbol is not fully resolved, we need to add a
 841           // dynamic relocation for it.
 842           if (!gsym->final_value_is_known(&options))
 843             gold_unreachable();
 844         }
 845       break;
 846
 847     case elfcpp::R_386_PLT32:
 848       // If the symbol is fully resolved, this is just a PC32 reloc.
 849       // Otherwise we need a PLT entry.
 850       if (gsym->final_value_is_known(&options))
 851         break;
 852       target->make_plt_entry(&options, symtab, layout, gsym);
 853       break;
 854
 855     case elfcpp::R_386_GOTOFF:
 856     case elfcpp::R_386_GOTPC:
 857       // We need a GOT section.
 858       target->got_section(&options, symtab, layout);
 859       break;
 860
 861     case elfcpp::R_386_COPY:
 862     case elfcpp::R_386_GLOB_DAT:
 863     case elfcpp::R_386_JUMP_SLOT:
 864     case elfcpp::R_386_RELATIVE:
 865     case elfcpp::R_386_TLS_TPOFF:
 866     case elfcpp::R_386_TLS_DTPMOD32:
 867     case elfcpp::R_386_TLS_DTPOFF32:
 868     case elfcpp::R_386_TLS_TPOFF32:
 869     case elfcpp::R_386_TLS_DESC:
 870       fprintf(stderr, _("%s: %s: unexpected reloc %u in object file\n"),
 871               program_name, object->name().c_str(), r_type);
 872       gold_exit(false);
 873       break;
 874
 875     case elfcpp::R_386_TLS_IE:
 876     case elfcpp::R_386_TLS_GOTIE:
 877     case elfcpp::R_386_TLS_LE:
 878     case elfcpp::R_386_TLS_GD:
 879     case elfcpp::R_386_TLS_LDM:
 880     case elfcpp::R_386_TLS_LDO_32:
 881     case elfcpp::R_386_TLS_IE_32:
 882     case elfcpp::R_386_TLS_LE_32:
 883     case elfcpp::R_386_TLS_GOTDESC:
 884     case elfcpp::R_386_TLS_DESC_CALL:
 885       {
 886         const bool is_final = gsym->final_value_is_known(&options);
 887         r_type = Target_i386::optimize_tls_reloc(&options, is_final, r_type);
 888         switch (r_type)
 889           {
 890           case elfcpp::R_386_TLS_LE:
 891           case elfcpp::R_386_TLS_LE_32:
 892             // FIXME: If generating a shared object, we need to copy
 893             // this relocation into the object.
 894             gold_assert(!options.is_shared());
 895             break;
 896
 897           case elfcpp::R_386_TLS_IE:
 898           case elfcpp::R_386_TLS_GOTIE:
 899           case elfcpp::R_386_TLS_GD:
 900           case elfcpp::R_386_TLS_LDM:
 901           case elfcpp::R_386_TLS_LDO_32:
 902           case elfcpp::R_386_TLS_IE_32:
 903           case elfcpp::R_386_TLS_GOTDESC:
 904           case elfcpp::R_386_TLS_DESC_CALL:
 905             fprintf(stderr,
 906                     _("%s: %s: unsupported reloc %u "
 907                       "against global symbol %s\n"),
 908                     program_name, object->name().c_str(), r_type,
 909                     gsym->name());
 910             break;
 911           }
 912       }
 913       break;
 914
 915     case elfcpp::R_386_32PLT:
 916     case elfcpp::R_386_TLS_GD_32:
 917     case elfcpp::R_386_TLS_GD_PUSH:
 918     case elfcpp::R_386_TLS_GD_CALL:
 919     case elfcpp::R_386_TLS_GD_POP:
 920     case elfcpp::R_386_TLS_LDM_32:
 921     case elfcpp::R_386_TLS_LDM_PUSH:
 922     case elfcpp::R_386_TLS_LDM_CALL:
 923     case elfcpp::R_386_TLS_LDM_POP:
 924     case elfcpp::R_386_USED_BY_INTEL_200:
 925     default:
 926       fprintf(stderr,
 927               _("%s: %s: unsupported reloc %u against global symbol %s\n"),
 928               program_name, object->name().c_str(), r_type, gsym->name());
 929       break;
 930     }
 931 }
 932
 933 // Scan relocations for a section.
 934
 935 void
 936 Target_i386::scan_relocs(const General_options& options,
 937                          Symbol_table* symtab,
 938                          Layout* layout,
 939                          Sized_relobj<32, false>* object,
 940                          unsigned int data_shndx,
 941                          unsigned int sh_type,
 942                          const unsigned char* prelocs,
 943                          size_t reloc_count,
 944                          size_t local_symbol_count,
 945                          const unsigned char* plocal_symbols,
 946                          Symbol** global_symbols)
 947 {
 948   if (sh_type == elfcpp::SHT_RELA)
 949     {
 950       fprintf(stderr, _("%s: %s: unsupported RELA reloc section\n"),
 951               program_name, object->name().c_str());
 952       gold_exit(false);
 953     }
 954
 955   gold::scan_relocs<32, false, Target_i386, elfcpp::SHT_REL,
 956                     Target_i386::Scan>(
 957     options,
 958     symtab,
 959     layout,
 960     this,
 961     object,
 962     data_shndx,
 963     prelocs,
 964     reloc_count,
 965     local_symbol_count,
 966     plocal_symbols,
 967     global_symbols);
 968 }
 969
 970 // Finalize the sections.
 971
 972 void
 973 Target_i386::do_finalize_sections(const General_options* options,
 974                                   Layout* layout)
 975 {
 976   // Fill in some more dynamic tags.
 977   Output_data_dynamic* const odyn = layout->dynamic_data();
 978   if (odyn != NULL)
 979     {
 980       if (this->got_plt_ != NULL)
 981         odyn->add_section_address(elfcpp::DT_PLTGOT, this->got_plt_);
 982
 983       if (this->plt_ != NULL)
 984         {
 985           const Output_data* od = this->plt_->rel_plt();
 986           odyn->add_section_size(elfcpp::DT_PLTRELSZ, od);
 987           odyn->add_section_address(elfcpp::DT_JMPREL, od);
 988           odyn->add_constant(elfcpp::DT_PLTREL, elfcpp::DT_REL);
 989         }
 990
 991       if (this->rel_dyn_ != NULL)
 992         {
 993           const Output_data* od = this->rel_dyn_;
 994           odyn->add_section_address(elfcpp::DT_REL, od);
 995           odyn->add_section_size(elfcpp::DT_RELSZ, od);
 996           odyn->add_constant(elfcpp::DT_RELENT,
 997                              elfcpp::Elf_sizes<32>::rel_size);
 998         }
 999
1000       if (!options->is_shared())
1001         {
1002           // The value of the DT_DEBUG tag is filled in by the dynamic
1003           // linker at run time, and used by the debugger.
1004           odyn->add_constant(elfcpp::DT_DEBUG, 0);
1005         }
1006     }
1007
1008   // Emit any relocs we saved in an attempt to avoid generating COPY
1009   // relocs.
1010   if (this->copy_relocs_ == NULL)
1011     return;
1012   if (this->copy_relocs_->any_to_emit())
1013     {
1014       Reloc_section* rel_dyn = this->rel_dyn_section(layout);
1015       this->copy_relocs_->emit(rel_dyn);
1016     }
1017   delete this->copy_relocs_;
1018   this->copy_relocs_ = NULL;
1019 }
1020
1021 // Perform a relocation.
1022
1023 inline bool
1024 Target_i386::Relocate::relocate(const Relocate_info<32, false>* relinfo,
1025                                 Target_i386* target,
1026                                 size_t relnum,
1027                                 const elfcpp::Rel<32, false>& rel,
1028                                 unsigned int r_type,
1029                                 const Sized_symbol<32>* gsym,
1030                                 const Symbol_value<32>* psymval,
1031                                 unsigned char* view,
1032                                 elfcpp::Elf_types<32>::Elf_Addr address,
1033                                 off_t view_size)
1034 {
1035   if (this->skip_call_tls_get_addr_)
1036     {
1037       if (r_type != elfcpp::R_386_PLT32
1038           || gsym == NULL
1039           || strcmp(gsym->name(), "___tls_get_addr") != 0)
1040         {
1041           fprintf(stderr, _("%s: %s: missing expected TLS relocation\n"),
1042                   program_name,
1043                   relinfo->location(relnum, rel.get_r_offset()).c_str());
1044           gold_exit(false);
1045         }
1046
1047       this->skip_call_tls_get_addr_ = false;
1048
1049       return false;
1050     }
1051
1052   // Pick the value to use for symbols defined in shared objects.
1053   Symbol_value<32> symval;
1054   if (gsym != NULL && gsym->is_from_dynobj())
1055     {
1056       if (!gsym->has_plt_offset())
1057         gold_unreachable();
1058
1059       symval.set_output_value(target->plt_section()->address()
1060                               + gsym->plt_offset());
1061       psymval = &symval;
1062     }
1063
1064   const Sized_relobj<32, false>* object = relinfo->object;
1065
1066   switch (r_type)
1067     {
1068     case elfcpp::R_386_NONE:
1069     case elfcpp::R_386_GNU_VTINHERIT:
1070     case elfcpp::R_386_GNU_VTENTRY:
1071       break;
1072
1073     case elfcpp::R_386_32:
1074       Relocate_functions<32, false>::rel32(view, object, psymval);
1075       break;
1076
1077     case elfcpp::R_386_PC32:
1078       Relocate_functions<32, false>::pcrel32(view, object, psymval, address);
1079       break;
1080
1081     case elfcpp::R_386_16:
1082       Relocate_functions<32, false>::rel16(view, object, psymval);
1083       break;
1084
1085     case elfcpp::R_386_PC16:
1086       Relocate_functions<32, false>::pcrel16(view, object, psymval, address);
1087       break;
1088
1089     case elfcpp::R_386_8:
1090       Relocate_functions<32, false>::rel8(view, object, psymval);
1091       break;
1092
1093     case elfcpp::R_386_PC8:
1094       Relocate_functions<32, false>::pcrel8(view, object, psymval, address);
1095       break;
1096
1097     case elfcpp::R_386_PLT32:
1098       gold_assert(gsym->has_plt_offset()
1099                   || gsym->final_value_is_known(relinfo->options));
1100       Relocate_functions<32, false>::pcrel32(view, object, psymval, address);
1101       break;
1102
1103     case elfcpp::R_386_GOT32:
1104       // Local GOT offsets not yet supported.
1105       gold_assert(gsym);
1106       gold_assert(gsym->has_got_offset());
1107       Relocate_functions<32, false>::rel32(view, gsym->got_offset());
1108       break;
1109
1110     case elfcpp::R_386_GOTOFF:
1111       {
1112         elfcpp::Elf_types<32>::Elf_Addr value;
1113         value = (psymval->value(object, 0)
1114                  - target->got_section(NULL, NULL, NULL)->address());
1115         Relocate_functions<32, false>::rel32(view, value);
1116       }
1117       break;
1118
1119     case elfcpp::R_386_GOTPC:
1120       {
1121         elfcpp::Elf_types<32>::Elf_Addr value;
1122         value = target->got_section(NULL, NULL, NULL)->address();
1123         Relocate_functions<32, false>::pcrel32(view, value, address);
1124       }
1125       break;
1126
1127     case elfcpp::R_386_COPY:
1128     case elfcpp::R_386_GLOB_DAT:
1129     case elfcpp::R_386_JUMP_SLOT:
1130     case elfcpp::R_386_RELATIVE:
1131     case elfcpp::R_386_TLS_TPOFF:
1132     case elfcpp::R_386_TLS_DTPMOD32:
1133     case elfcpp::R_386_TLS_DTPOFF32:
1134     case elfcpp::R_386_TLS_TPOFF32:
1135     case elfcpp::R_386_TLS_DESC:
1136       fprintf(stderr, _("%s: %s: unexpected reloc %u in object file\n"),
1137               program_name,
1138               relinfo->location(relnum, rel.get_r_offset()).c_str(),
1139               r_type);
1140       gold_exit(false);
1141       break;
1142
1143     case elfcpp::R_386_TLS_IE:
1144     case elfcpp::R_386_TLS_GOTIE:
1145     case elfcpp::R_386_TLS_LE:
1146     case elfcpp::R_386_TLS_GD:
1147     case elfcpp::R_386_TLS_LDM:
1148     case elfcpp::R_386_TLS_LDO_32:
1149     case elfcpp::R_386_TLS_IE_32:
1150     case elfcpp::R_386_TLS_LE_32:
1151     case elfcpp::R_386_TLS_GOTDESC:
1152     case elfcpp::R_386_TLS_DESC_CALL:
1153       this->relocate_tls(relinfo, relnum, rel, r_type, gsym, psymval, view,
1154                          address, view_size);
1155       break;
1156
1157     case elfcpp::R_386_32PLT:
1158     case elfcpp::R_386_TLS_GD_32:
1159     case elfcpp::R_386_TLS_GD_PUSH:
1160     case elfcpp::R_386_TLS_GD_CALL:
1161     case elfcpp::R_386_TLS_GD_POP:
1162     case elfcpp::R_386_TLS_LDM_32:
1163     case elfcpp::R_386_TLS_LDM_PUSH:
1164     case elfcpp::R_386_TLS_LDM_CALL:
1165     case elfcpp::R_386_TLS_LDM_POP:
1166     case elfcpp::R_386_USED_BY_INTEL_200:
1167     default:
1168       fprintf(stderr, _("%s: %s: unsupported reloc %u\n"),
1169               program_name,
1170               relinfo->location(relnum, rel.get_r_offset()).c_str(),
1171               r_type);
1172       // gold_exit(false);
1173       break;
1174     }
1175
1176   return true;
1177 }
1178
1179 // Perform a TLS relocation.
1180
1181 inline void
1182 Target_i386::Relocate::relocate_tls(const Relocate_info<32, false>* relinfo,
1183                                     size_t relnum,
1184                                     const elfcpp::Rel<32, false>& rel,
1185                                     unsigned int r_type,
1186                                     const Sized_symbol<32>* gsym,
1187                                     const Symbol_value<32>* psymval,
1188                                     unsigned char* view,
1189                                     elfcpp::Elf_types<32>::Elf_Addr,
1190                                     off_t view_size)
1191 {
1192   Output_segment* tls_segment = relinfo->layout->tls_segment();
1193   if (tls_segment == NULL)
1194     {
1195       fprintf(stderr, _("%s: %s: TLS reloc but no TLS segment\n"),
1196               program_name,
1197               relinfo->location(relnum, rel.get_r_offset()).c_str());
1198       gold_exit(false);
1199     }
1200
1201   elfcpp::Elf_types<32>::Elf_Addr value = psymval->value(relinfo->object, 0);
1202
1203   const bool is_final = (gsym == NULL
1204                          ? !relinfo->options->is_shared()
1205                          : gsym->final_value_is_known(relinfo->options));
1206   const unsigned int opt_r_type =
1207     Target_i386::optimize_tls_reloc(relinfo->options, is_final, r_type);
1208   switch (r_type)
1209     {
1210     case elfcpp::R_386_TLS_LE_32:
1211       value = tls_segment->vaddr() + tls_segment->memsz() - value;
1212       Relocate_functions<32, false>::rel32(view, value);
1213       break;
1214
1215     case elfcpp::R_386_TLS_LE:
1216       value = value - (tls_segment->vaddr() + tls_segment->memsz());
1217       Relocate_functions<32, false>::rel32(view, value);
1218       break;
1219
1220     case elfcpp::R_386_TLS_IE:
1221     case elfcpp::R_386_TLS_GOTIE:
1222     case elfcpp::R_386_TLS_IE_32:
1223       if (opt_r_type == elfcpp::R_386_TLS_LE_32)
1224         {
1225           Target_i386::Relocate::tls_ie_to_le(relinfo, relnum, tls_segment,
1226                                               rel, r_type, value, view,
1227                                               view_size);
1228           break;
1229         }
1230       fprintf(stderr, _("%s: %s: unsupported reloc type %u\n"),
1231               program_name,
1232               relinfo->location(relnum, rel.get_r_offset()).c_str(),
1233               r_type);
1234       // gold_exit(false);
1235       break;
1236
1237     case elfcpp::R_386_TLS_GD:
1238       if (opt_r_type == elfcpp::R_386_TLS_LE_32)
1239         {
1240           this->tls_gd_to_le(relinfo, relnum, tls_segment,
1241                              rel, r_type, value, view,
1242                              view_size);
1243           break;
1244         }
1245       fprintf(stderr, _("%s: %s: unsupported reloc %u\n"),
1246               program_name,
1247               relinfo->location(relnum, rel.get_r_offset()).c_str(),
1248               r_type);
1249       // gold_exit(false);
1250       break;
1251
1252     case elfcpp::R_386_TLS_LDM:
1253     case elfcpp::R_386_TLS_LDO_32:
1254     case elfcpp::R_386_TLS_GOTDESC:
1255     case elfcpp::R_386_TLS_DESC_CALL:
1256       fprintf(stderr, _("%s: %s: unsupported reloc %u\n"),
1257               program_name,
1258               relinfo->location(relnum, rel.get_r_offset()).c_str(),
1259               r_type);
1260       // gold_exit(false);
1261       break;
1262     }
1263 }
1264
1265 // Do a relocation in which we convert a TLS Initial-Exec to a
1266 // Local-Exec.
1267
1268 inline void
1269 Target_i386::Relocate::tls_ie_to_le(const Relocate_info<32, false>* relinfo,
1270                                     size_t relnum,
1271                                     Output_segment* tls_segment,
1272                                     const elfcpp::Rel<32, false>& rel,
1273                                     unsigned int r_type,
1274                                     elfcpp::Elf_types<32>::Elf_Addr value,
1275                                     unsigned char* view,
1276                                     off_t view_size)
1277 {
1278   // We have to actually change the instructions, which means that we
1279   // need to examine the opcodes to figure out which instruction we
1280   // are looking at.
1281   if (r_type == elfcpp::R_386_TLS_IE)
1282     {
1283       // movl %gs:XX,%eax  ==>  movl $YY,%eax
1284       // movl %gs:XX,%reg  ==>  movl $YY,%reg
1285       // addl %gs:XX,%reg  ==>  addl $YY,%reg
1286       Target_i386::Relocate::check_range(relinfo, relnum, rel, view_size, -1);
1287       Target_i386::Relocate::check_range(relinfo, relnum, rel, view_size, 4);
1288
1289       unsigned char op1 = view[-1];
1290       if (op1 == 0xa1)
1291         {
1292           // movl XX,%eax  ==>  movl $YY,%eax
1293           view[-1] = 0xb8;
1294         }
1295       else
1296         {
1297           Target_i386::Relocate::check_range(relinfo, relnum, rel,
1298                                              view_size, -2);
1299
1300           unsigned char op2 = view[-2];
1301           if (op2 == 0x8b)
1302             {
1303               // movl XX,%reg  ==>  movl $YY,%reg
1304               Target_i386::Relocate::check_tls(relinfo, relnum, rel,
1305                                                (op1 & 0xc7) == 0x05);
1306               view[-2] = 0xc7;
1307               view[-1] = 0xc0 | ((op1 >> 3) & 7);
1308             }
1309           else if (op2 == 0x03)
1310             {
1311               // addl XX,%reg  ==>  addl $YY,%reg
1312               Target_i386::Relocate::check_tls(relinfo, relnum, rel,
1313                                                (op1 & 0xc7) == 0x05);
1314               view[-2] = 0x81;
1315               view[-1] = 0xc0 | ((op1 >> 3) & 7);
1316             }
1317           else
1318             Target_i386::Relocate::check_tls(relinfo, relnum, rel, 0);
1319         }
1320     }
1321   else
1322     {
1323       // subl %gs:XX(%reg1),%reg2  ==>  subl $YY,%reg2
1324       // movl %gs:XX(%reg1),%reg2  ==>  movl $YY,%reg2
1325       // addl %gs:XX(%reg1),%reg2  ==>  addl $YY,$reg2
1326       Target_i386::Relocate::check_range(relinfo, relnum, rel, view_size, -2);
1327       Target_i386::Relocate::check_range(relinfo, relnum, rel, view_size, 4);
1328
1329       unsigned char op1 = view[-1];
1330       unsigned char op2 = view[-2];
1331       Target_i386::Relocate::check_tls(relinfo, relnum, rel,
1332                                        (op1 & 0xc0) == 0x80 && (op1 & 7) != 4);
1333       if (op2 == 0x8b)
1334         {
1335           // movl %gs:XX(%reg1),%reg2  ==>  movl $YY,%reg2
1336           view[-2] = 0xc7;
1337           view[-1] = 0xc0 | ((op1 >> 3) & 7);
1338         }
1339       else if (op2 == 0x2b)
1340         {
1341           // subl %gs:XX(%reg1),%reg2  ==>  subl $YY,%reg2
1342           view[-2] = 0x81;
1343           view[-1] = 0xe8 | ((op1 >> 3) & 7);
1344         }
1345       else if (op2 == 0x03)
1346         {
1347           // addl %gs:XX(%reg1),%reg2  ==>  addl $YY,$reg2
1348           view[-2] = 0x81;
1349           view[-1] = 0xc0 | ((op1 >> 3) & 7);
1350         }
1351       else
1352         Target_i386::Relocate::check_tls(relinfo, relnum, rel, 0);
1353     }
1354
1355   value = tls_segment->vaddr() + tls_segment->memsz() - value;
1356   if (r_type == elfcpp::R_386_TLS_IE || r_type == elfcpp::R_386_TLS_GOTIE)
1357     value = - value;
1358
1359   Relocate_functions<32, false>::rel32(view, value);
1360 }
1361
1362 // Do a relocation in which we convert a TLS Global-Dynamic to a
1363 // Local-Exec.
1364
1365 inline void
1366 Target_i386::Relocate::tls_gd_to_le(const Relocate_info<32, false>* relinfo,
1367                                     size_t relnum,
1368                                     Output_segment* tls_segment,
1369                                     const elfcpp::Rel<32, false>& rel,
1370                                     unsigned int,
1371                                     elfcpp::Elf_types<32>::Elf_Addr value,
1372                                     unsigned char* view,
1373                                     off_t view_size)
1374 {
1375   // leal foo(,%reg,1),%eax; call ___tls_get_addr
1376   //  ==> movl %gs,0,%eax; subl $foo@tpoff,%eax
1377   // leal foo(%reg),%eax; call ___tls_get_addr
1378   //  ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
1379
1380   Target_i386::Relocate::check_range(relinfo, relnum, rel, view_size, -2);
1381   Target_i386::Relocate::check_range(relinfo, relnum, rel, view_size, 9);
1382
1383   unsigned char op1 = view[-1];
1384   unsigned char op2 = view[-2];
1385
1386   Target_i386::Relocate::check_tls(relinfo, relnum, rel,
1387                                    op2 == 0x8d || op2 == 0x04);
1388   Target_i386::Relocate::check_tls(relinfo, relnum, rel,
1389                                    view[4] == 0xe8);
1390
1391   int roff = 5;
1392
1393   if (op2 == 0x04)
1394     {
1395       Target_i386::Relocate::check_range(relinfo, relnum, rel, view_size, -3);
1396       Target_i386::Relocate::check_tls(relinfo, relnum, rel,
1397                                        view[-3] == 0x8d);
1398       Target_i386::Relocate::check_tls(relinfo, relnum, rel,
1399                                        ((op1 & 0xc7) == 0x05
1400                                         && op1 != (4 << 3)));
1401       memcpy(view - 3, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
1402     }
1403   else
1404     {
1405       Target_i386::Relocate::check_tls(relinfo, relnum, rel,
1406                                        (op1 & 0xf8) == 0x80 && (op1 & 7) != 4);
1407       if (rel.get_r_offset() + 9 < view_size && view[9] == 0x90)
1408         {
1409           // There is a trailing nop.  Use the size byte subl.
1410           memcpy(view - 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
1411           roff = 6;
1412         }
1413       else
1414         {
1415           // Use the five byte subl.
1416           memcpy(view - 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
1417         }
1418     }
1419
1420   value = tls_segment->vaddr() + tls_segment->memsz() - value;
1421   Relocate_functions<32, false>::rel32(view + roff, value);
1422
1423   // The next reloc should be a PLT32 reloc against __tls_get_addr.
1424   // We can skip it.
1425   this->skip_call_tls_get_addr_ = true;
1426 }
1427
1428 // Check the range for a TLS relocation.
1429
1430 inline void
1431 Target_i386::Relocate::check_range(const Relocate_info<32, false>* relinfo,
1432                                    size_t relnum,
1433                                    const elfcpp::Rel<32, false>& rel,
1434                                    off_t view_size, off_t off)
1435 {
1436   off_t offset = rel.get_r_offset() + off;
1437   if (offset < 0 || offset > view_size)
1438     {
1439       fprintf(stderr, _("%s: %s: TLS relocation out of range\n"),
1440               program_name,
1441               relinfo->location(relnum, rel.get_r_offset()).c_str());
1442       gold_exit(false);
1443     }
1444 }
1445
1446 // Check the validity of a TLS relocation.  This is like assert.
1447
1448 inline void
1449 Target_i386::Relocate::check_tls(const Relocate_info<32, false>* relinfo,
1450                                  size_t relnum,
1451                                  const elfcpp::Rel<32, false>& rel,
1452                                  bool valid)
1453 {
1454   if (!valid)
1455     {
1456       fprintf(stderr,
1457               _("%s: %s: TLS relocation against invalid instruction\n"),
1458               program_name,
1459               relinfo->location(relnum, rel.get_r_offset()).c_str());
1460       gold_exit(false);
1461     }
1462 }
1463
1464 // Relocate section data.
1465
1466 void
1467 Target_i386::relocate_section(const Relocate_info<32, false>* relinfo,
1468                               unsigned int sh_type,
1469                               const unsigned char* prelocs,
1470                               size_t reloc_count,
1471                               unsigned char* view,
1472                               elfcpp::Elf_types<32>::Elf_Addr address,
1473                               off_t view_size)
1474 {
1475   gold_assert(sh_type == elfcpp::SHT_REL);
1476
1477   gold::relocate_section<32, false, Target_i386, elfcpp::SHT_REL,
1478                          Target_i386::Relocate>(
1479     relinfo,
1480     this,
1481     prelocs,
1482     reloc_count,
1483     view,
1484     address,
1485     view_size);
1486 }
1487
1488 // The selector for i386 object files.
1489
1490 class Target_selector_i386 : public Target_selector
1491 {
1492 public:
1493   Target_selector_i386()
1494     : Target_selector(elfcpp::EM_386, 32, false)
1495   { }
1496
1497   Target*
1498   recognize(int machine, int osabi, int abiversion);
1499
1500  private:
1501   Target_i386* target_;
1502 };
1503
1504 // Recognize an i386 object file when we already know that the machine
1505 // number is EM_386.
1506
1507 Target*
1508 Target_selector_i386::recognize(int, int, int)
1509 {
1510   if (this->target_ == NULL)
1511     this->target_ = new Target_i386();
1512   return this->target_;
1513 }
1514
1515 Target_selector_i386 target_selector_i386;
1516
1517 } // End anonymous namespace.