Avoid some warnings which showed up in 64-bit mode.
[external/binutils.git] / gold / i386.cc
1 // i386.cc -- i386 target support for gold.
2
3 // Copyright 2006, 2007 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 "i386.h"
31 #include "object.h"
32 #include "symtab.h"
33 #include "layout.h"
34 #include "output.h"
35 #include "target.h"
36 #include "target-reloc.h"
37 #include "target-select.h"
38 #include "tls.h"
39
40 namespace
41 {
42
43 using namespace gold;
44
45 class Output_data_plt_i386;
46
47 // The i386 target class.
48 // TLS info comes from
49 //   http://people.redhat.com/drepper/tls.pdf
50 //   http://www.lsd.ic.unicamp.br/~oliva/writeups/TLS/RFC-TLSDESC-x86.txt
51
52 class Target_i386 : public Sized_target<32, false>
53 {
54  public:
55   typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, false> Reloc_section;
56
57   Target_i386()
58     : Sized_target<32, false>(&i386_info),
59       got_(NULL), plt_(NULL), got_plt_(NULL), rel_dyn_(NULL),
60       copy_relocs_(NULL), dynbss_(NULL), got_mod_index_offset_(-1U)
61   { }
62
63   // Scan the relocations to look for symbol adjustments.
64   void
65   scan_relocs(const General_options& options,
66               Symbol_table* symtab,
67               Layout* layout,
68               Sized_relobj<32, false>* object,
69               unsigned int data_shndx,
70               unsigned int sh_type,
71               const unsigned char* prelocs,
72               size_t reloc_count,
73               Output_section* output_section,
74               bool needs_special_offset_handling,
75               size_t local_symbol_count,
76               const unsigned char* plocal_symbols);
77
78   // Finalize the sections.
79   void
80   do_finalize_sections(Layout*);
81
82   // Return the value to use for a dynamic which requires special
83   // treatment.
84   uint64_t
85   do_dynsym_value(const Symbol*) const;
86
87   // Relocate a section.
88   void
89   relocate_section(const Relocate_info<32, false>*,
90                    unsigned int sh_type,
91                    const unsigned char* prelocs,
92                    size_t reloc_count,
93                    Output_section* output_section,
94                    bool needs_special_offset_handling,
95                    unsigned char* view,
96                    elfcpp::Elf_types<32>::Elf_Addr view_address,
97                    off_t view_size);
98
99   // Return a string used to fill a code section with nops.
100   std::string
101   do_code_fill(off_t length);
102
103   // Return whether SYM is defined by the ABI.
104   bool
105   do_is_defined_by_abi(Symbol* sym) const
106   { return strcmp(sym->name(), "___tls_get_addr") == 0; }
107
108   // Return the size of the GOT section.
109   off_t
110   got_size()
111   {
112     gold_assert(this->got_ != NULL);
113     return this->got_->data_size();
114   }
115
116  private:
117   // The class which scans relocations.
118   struct Scan
119   {
120     inline void
121     local(const General_options& options, Symbol_table* symtab,
122           Layout* layout, Target_i386* target,
123           Sized_relobj<32, false>* object,
124           unsigned int data_shndx,
125           Output_section* output_section,
126           const elfcpp::Rel<32, false>& reloc, unsigned int r_type,
127           const elfcpp::Sym<32, false>& lsym);
128
129     inline void
130     global(const General_options& options, Symbol_table* symtab,
131            Layout* layout, Target_i386* target,
132            Sized_relobj<32, false>* object,
133            unsigned int data_shndx,
134            Output_section* output_section,
135            const elfcpp::Rel<32, false>& reloc, unsigned int r_type,
136            Symbol* gsym);
137
138     static void
139     unsupported_reloc_local(Sized_relobj<32, false>*, unsigned int r_type);
140
141     static void
142     unsupported_reloc_global(Sized_relobj<32, false>*, unsigned int r_type,
143                              Symbol*);
144   };
145
146   // The class which implements relocation.
147   class Relocate
148   {
149    public:
150     Relocate()
151       : skip_call_tls_get_addr_(false),
152         local_dynamic_type_(LOCAL_DYNAMIC_NONE)
153     { }
154
155     ~Relocate()
156     {
157       if (this->skip_call_tls_get_addr_)
158         {
159           // FIXME: This needs to specify the location somehow.
160           gold_error(_("missing expected TLS relocation"));
161         }
162     }
163
164     // Return whether the static relocation needs to be applied.
165     inline bool
166     should_apply_static_reloc(const Sized_symbol<32>* gsym,
167                               bool is_absolute_ref,
168                               bool is_function_call,
169                               bool is_32bit);
170
171     // Do a relocation.  Return false if the caller should not issue
172     // any warnings about this relocation.
173     inline bool
174     relocate(const Relocate_info<32, false>*, Target_i386*, size_t relnum,
175              const elfcpp::Rel<32, false>&,
176              unsigned int r_type, const Sized_symbol<32>*,
177              const Symbol_value<32>*,
178              unsigned char*, elfcpp::Elf_types<32>::Elf_Addr,
179              off_t);
180
181    private:
182     // Do a TLS relocation.
183     inline void
184     relocate_tls(const Relocate_info<32, false>*, Target_i386* target,
185                  size_t relnum, const elfcpp::Rel<32, false>&,
186                  unsigned int r_type, const Sized_symbol<32>*,
187                  const Symbol_value<32>*,
188                  unsigned char*, elfcpp::Elf_types<32>::Elf_Addr, off_t);
189
190     // Do a TLS General-Dynamic to Initial-Exec transition.
191     inline void
192     tls_gd_to_ie(const Relocate_info<32, false>*, size_t relnum,
193                  Output_segment* tls_segment,
194                  const elfcpp::Rel<32, false>&, unsigned int r_type,
195                  elfcpp::Elf_types<32>::Elf_Addr value,
196                  unsigned char* view,
197                  off_t view_size);
198
199     // Do a TLS General-Dynamic to Local-Exec transition.
200     inline void
201     tls_gd_to_le(const Relocate_info<32, false>*, size_t relnum,
202                  Output_segment* tls_segment,
203                  const elfcpp::Rel<32, false>&, unsigned int r_type,
204                  elfcpp::Elf_types<32>::Elf_Addr value,
205                  unsigned char* view,
206                  off_t view_size);
207
208     // Do a TLS Local-Dynamic to Local-Exec transition.
209     inline void
210     tls_ld_to_le(const Relocate_info<32, false>*, size_t relnum,
211                  Output_segment* tls_segment,
212                  const elfcpp::Rel<32, false>&, unsigned int r_type,
213                  elfcpp::Elf_types<32>::Elf_Addr value,
214                  unsigned char* view,
215                  off_t view_size);
216
217     // Do a TLS Initial-Exec to Local-Exec transition.
218     static inline void
219     tls_ie_to_le(const Relocate_info<32, false>*, size_t relnum,
220                  Output_segment* tls_segment,
221                  const elfcpp::Rel<32, false>&, unsigned int r_type,
222                  elfcpp::Elf_types<32>::Elf_Addr value,
223                  unsigned char* view,
224                  off_t view_size);
225
226     // We need to keep track of which type of local dynamic relocation
227     // we have seen, so that we can optimize R_386_TLS_LDO_32 correctly.
228     enum Local_dynamic_type
229     {
230       LOCAL_DYNAMIC_NONE,
231       LOCAL_DYNAMIC_SUN,
232       LOCAL_DYNAMIC_GNU
233     };
234
235     // This is set if we should skip the next reloc, which should be a
236     // PLT32 reloc against ___tls_get_addr.
237     bool skip_call_tls_get_addr_;
238     // The type of local dynamic relocation we have seen in the section
239     // being relocated, if any.
240     Local_dynamic_type local_dynamic_type_;
241   };
242
243   // Adjust TLS relocation type based on the options and whether this
244   // is a local symbol.
245   static tls::Tls_optimization
246   optimize_tls_reloc(bool is_final, int r_type);
247
248   // Get the GOT section, creating it if necessary.
249   Output_data_got<32, false>*
250   got_section(Symbol_table*, Layout*);
251
252   // Get the GOT PLT section.
253   Output_data_space*
254   got_plt_section() const
255   {
256     gold_assert(this->got_plt_ != NULL);
257     return this->got_plt_;
258   }
259
260   // Create a PLT entry for a global symbol.
261   void
262   make_plt_entry(Symbol_table*, Layout*, Symbol*);
263
264   // Create a GOT entry for the TLS module index.
265   unsigned int
266   got_mod_index_entry(Symbol_table* symtab, Layout* layout,
267                       Sized_relobj<32, false>* object);
268
269   // Get the PLT section.
270   const Output_data_plt_i386*
271   plt_section() const
272   {
273     gold_assert(this->plt_ != NULL);
274     return this->plt_;
275   }
276
277   // Get the dynamic reloc section, creating it if necessary.
278   Reloc_section*
279   rel_dyn_section(Layout*);
280
281   // Return true if the symbol may need a COPY relocation.
282   // References from an executable object to non-function symbols
283   // defined in a dynamic object may need a COPY relocation.
284   bool
285   may_need_copy_reloc(Symbol* gsym)
286   {
287     return (!parameters->output_is_shared()
288             && gsym->is_from_dynobj()
289             && gsym->type() != elfcpp::STT_FUNC);
290   }
291
292   // Copy a relocation against a global symbol.
293   void
294   copy_reloc(const General_options*, Symbol_table*, Layout*,
295              Sized_relobj<32, false>*, unsigned int,
296              Output_section*, Symbol*, const elfcpp::Rel<32, false>&);
297
298   // Information about this specific target which we pass to the
299   // general Target structure.
300   static const Target::Target_info i386_info;
301
302   // The GOT section.
303   Output_data_got<32, false>* got_;
304   // The PLT section.
305   Output_data_plt_i386* plt_;
306   // The GOT PLT section.
307   Output_data_space* got_plt_;
308   // The dynamic reloc section.
309   Reloc_section* rel_dyn_;
310   // Relocs saved to avoid a COPY reloc.
311   Copy_relocs<32, false>* copy_relocs_;
312   // Space for variables copied with a COPY reloc.
313   Output_data_space* dynbss_;
314   // Offset of the GOT entry for the TLS module index;
315   unsigned int got_mod_index_offset_;
316 };
317
318 const Target::Target_info Target_i386::i386_info =
319 {
320   32,                   // size
321   false,                // is_big_endian
322   elfcpp::EM_386,       // machine_code
323   false,                // has_make_symbol
324   false,                // has_resolve
325   true,                 // has_code_fill
326   true,                 // is_default_stack_executable
327   "/usr/lib/libc.so.1", // dynamic_linker
328   0x08048000,           // default_text_segment_address
329   0x1000,               // abi_pagesize
330   0x1000                // common_pagesize
331 };
332
333 // Get the GOT section, creating it if necessary.
334
335 Output_data_got<32, false>*
336 Target_i386::got_section(Symbol_table* symtab, Layout* layout)
337 {
338   if (this->got_ == NULL)
339     {
340       gold_assert(symtab != NULL && layout != NULL);
341
342       this->got_ = new Output_data_got<32, false>();
343
344       layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
345                                       elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE,
346                                       this->got_);
347
348       // The old GNU linker creates a .got.plt section.  We just
349       // create another set of data in the .got section.  Note that we
350       // always create a PLT if we create a GOT, although the PLT
351       // might be empty.
352       this->got_plt_ = new Output_data_space(4);
353       layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
354                                       elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE,
355                                       this->got_plt_);
356
357       // The first three entries are reserved.
358       this->got_plt_->set_current_data_size(3 * 4);
359
360       // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
361       symtab->define_in_output_data(this, "_GLOBAL_OFFSET_TABLE_", NULL,
362                                     this->got_plt_,
363                                     0, 0, elfcpp::STT_OBJECT,
364                                     elfcpp::STB_LOCAL,
365                                     elfcpp::STV_HIDDEN, 0,
366                                     false, false);
367     }
368
369   return this->got_;
370 }
371
372 // Get the dynamic reloc section, creating it if necessary.
373
374 Target_i386::Reloc_section*
375 Target_i386::rel_dyn_section(Layout* layout)
376 {
377   if (this->rel_dyn_ == NULL)
378     {
379       gold_assert(layout != NULL);
380       this->rel_dyn_ = new Reloc_section();
381       layout->add_output_section_data(".rel.dyn", elfcpp::SHT_REL,
382                                       elfcpp::SHF_ALLOC, this->rel_dyn_);
383     }
384   return this->rel_dyn_;
385 }
386
387 // A class to handle the PLT data.
388
389 class Output_data_plt_i386 : public Output_section_data
390 {
391  public:
392   typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, false> Reloc_section;
393
394   Output_data_plt_i386(Layout*, Output_data_space*);
395
396   // Add an entry to the PLT.
397   void
398   add_entry(Symbol* gsym);
399
400   // Return the .rel.plt section data.
401   const Reloc_section*
402   rel_plt() const
403   { return this->rel_; }
404
405  protected:
406   void
407   do_adjust_output_section(Output_section* os);
408
409  private:
410   // The size of an entry in the PLT.
411   static const int plt_entry_size = 16;
412
413   // The first entry in the PLT for an executable.
414   static unsigned char exec_first_plt_entry[plt_entry_size];
415
416   // The first entry in the PLT for a shared object.
417   static unsigned char dyn_first_plt_entry[plt_entry_size];
418
419   // Other entries in the PLT for an executable.
420   static unsigned char exec_plt_entry[plt_entry_size];
421
422   // Other entries in the PLT for a shared object.
423   static unsigned char dyn_plt_entry[plt_entry_size];
424
425   // Set the final size.
426   void
427   set_final_data_size()
428   { this->set_data_size((this->count_ + 1) * plt_entry_size); }
429
430   // Write out the PLT data.
431   void
432   do_write(Output_file*);
433
434   // The reloc section.
435   Reloc_section* rel_;
436   // The .got.plt section.
437   Output_data_space* got_plt_;
438   // The number of PLT entries.
439   unsigned int count_;
440 };
441
442 // Create the PLT section.  The ordinary .got section is an argument,
443 // since we need to refer to the start.  We also create our own .got
444 // section just for PLT entries.
445
446 Output_data_plt_i386::Output_data_plt_i386(Layout* layout,
447                                            Output_data_space* got_plt)
448   : Output_section_data(4), got_plt_(got_plt), count_(0)
449 {
450   this->rel_ = new Reloc_section();
451   layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL,
452                                   elfcpp::SHF_ALLOC, this->rel_);
453 }
454
455 void
456 Output_data_plt_i386::do_adjust_output_section(Output_section* os)
457 {
458   // UnixWare sets the entsize of .plt to 4, and so does the old GNU
459   // linker, and so do we.
460   os->set_entsize(4);
461 }
462
463 // Add an entry to the PLT.
464
465 void
466 Output_data_plt_i386::add_entry(Symbol* gsym)
467 {
468   gold_assert(!gsym->has_plt_offset());
469
470   // Note that when setting the PLT offset we skip the initial
471   // reserved PLT entry.
472   gsym->set_plt_offset((this->count_ + 1) * plt_entry_size);
473
474   ++this->count_;
475
476   off_t got_offset = this->got_plt_->current_data_size();
477
478   // Every PLT entry needs a GOT entry which points back to the PLT
479   // entry (this will be changed by the dynamic linker, normally
480   // lazily when the function is called).
481   this->got_plt_->set_current_data_size(got_offset + 4);
482
483   // Every PLT entry needs a reloc.
484   gsym->set_needs_dynsym_entry();
485   this->rel_->add_global(gsym, elfcpp::R_386_JUMP_SLOT, this->got_plt_,
486                          got_offset);
487
488   // Note that we don't need to save the symbol.  The contents of the
489   // PLT are independent of which symbols are used.  The symbols only
490   // appear in the relocations.
491 }
492
493 // The first entry in the PLT for an executable.
494
495 unsigned char Output_data_plt_i386::exec_first_plt_entry[plt_entry_size] =
496 {
497   0xff, 0x35,   // pushl contents of memory address
498   0, 0, 0, 0,   // replaced with address of .got + 4
499   0xff, 0x25,   // jmp indirect
500   0, 0, 0, 0,   // replaced with address of .got + 8
501   0, 0, 0, 0    // unused
502 };
503
504 // The first entry in the PLT for a shared object.
505
506 unsigned char Output_data_plt_i386::dyn_first_plt_entry[plt_entry_size] =
507 {
508   0xff, 0xb3, 4, 0, 0, 0,       // pushl 4(%ebx)
509   0xff, 0xa3, 8, 0, 0, 0,       // jmp *8(%ebx)
510   0, 0, 0, 0                    // unused
511 };
512
513 // Subsequent entries in the PLT for an executable.
514
515 unsigned char Output_data_plt_i386::exec_plt_entry[plt_entry_size] =
516 {
517   0xff, 0x25,   // jmp indirect
518   0, 0, 0, 0,   // replaced with address of symbol in .got
519   0x68,         // pushl immediate
520   0, 0, 0, 0,   // replaced with offset into relocation table
521   0xe9,         // jmp relative
522   0, 0, 0, 0    // replaced with offset to start of .plt
523 };
524
525 // Subsequent entries in the PLT for a shared object.
526
527 unsigned char Output_data_plt_i386::dyn_plt_entry[plt_entry_size] =
528 {
529   0xff, 0xa3,   // jmp *offset(%ebx)
530   0, 0, 0, 0,   // replaced with offset of symbol in .got
531   0x68,         // pushl immediate
532   0, 0, 0, 0,   // replaced with offset into relocation table
533   0xe9,         // jmp relative
534   0, 0, 0, 0    // replaced with offset to start of .plt
535 };
536
537 // Write out the PLT.  This uses the hand-coded instructions above,
538 // and adjusts them as needed.  This is all specified by the i386 ELF
539 // Processor Supplement.
540
541 void
542 Output_data_plt_i386::do_write(Output_file* of)
543 {
544   const off_t offset = this->offset();
545   const off_t oview_size = this->data_size();
546   unsigned char* const oview = of->get_output_view(offset, oview_size);
547
548   const off_t got_file_offset = this->got_plt_->offset();
549   const off_t got_size = this->got_plt_->data_size();
550   unsigned char* const got_view = of->get_output_view(got_file_offset,
551                                                       got_size);
552
553   unsigned char* pov = oview;
554
555   elfcpp::Elf_types<32>::Elf_Addr plt_address = this->address();
556   elfcpp::Elf_types<32>::Elf_Addr got_address = this->got_plt_->address();
557
558   if (parameters->output_is_shared())
559     memcpy(pov, dyn_first_plt_entry, plt_entry_size);
560   else
561     {
562       memcpy(pov, exec_first_plt_entry, plt_entry_size);
563       elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_address + 4);
564       elfcpp::Swap<32, false>::writeval(pov + 8, got_address + 8);
565     }
566   pov += plt_entry_size;
567
568   unsigned char* got_pov = got_view;
569
570   memset(got_pov, 0, 12);
571   got_pov += 12;
572
573   const int rel_size = elfcpp::Elf_sizes<32>::rel_size;
574
575   unsigned int plt_offset = plt_entry_size;
576   unsigned int plt_rel_offset = 0;
577   unsigned int got_offset = 12;
578   const unsigned int count = this->count_;
579   for (unsigned int i = 0;
580        i < count;
581        ++i,
582          pov += plt_entry_size,
583          got_pov += 4,
584          plt_offset += plt_entry_size,
585          plt_rel_offset += rel_size,
586          got_offset += 4)
587     {
588       // Set and adjust the PLT entry itself.
589
590       if (parameters->output_is_shared())
591         {
592           memcpy(pov, dyn_plt_entry, plt_entry_size);
593           elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_offset);
594         }
595       else
596         {
597           memcpy(pov, exec_plt_entry, plt_entry_size);
598           elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
599                                                       (got_address
600                                                        + got_offset));
601         }
602
603       elfcpp::Swap_unaligned<32, false>::writeval(pov + 7, plt_rel_offset);
604       elfcpp::Swap<32, false>::writeval(pov + 12,
605                                         - (plt_offset + plt_entry_size));
606
607       // Set the entry in the GOT.
608       elfcpp::Swap<32, false>::writeval(got_pov, plt_address + plt_offset + 6);
609     }
610
611   gold_assert(pov - oview == oview_size);
612   gold_assert(got_pov - got_view == got_size);
613
614   of->write_output_view(offset, oview_size, oview);
615   of->write_output_view(got_file_offset, got_size, got_view);
616 }
617
618 // Create a PLT entry for a global symbol.
619
620 void
621 Target_i386::make_plt_entry(Symbol_table* symtab, Layout* layout, Symbol* gsym)
622 {
623   if (gsym->has_plt_offset())
624     return;
625
626   if (this->plt_ == NULL)
627     {
628       // Create the GOT sections first.
629       this->got_section(symtab, layout);
630
631       this->plt_ = new Output_data_plt_i386(layout, this->got_plt_);
632       layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
633                                       (elfcpp::SHF_ALLOC
634                                        | elfcpp::SHF_EXECINSTR),
635                                       this->plt_);
636     }
637
638   this->plt_->add_entry(gsym);
639 }
640
641 // Create a GOT entry for the TLS module index.
642
643 unsigned int
644 Target_i386::got_mod_index_entry(Symbol_table* symtab, Layout* layout,
645                                  Sized_relobj<32, false>* object)
646 {
647   if (this->got_mod_index_offset_ == -1U)
648     {
649       gold_assert(symtab != NULL && layout != NULL && object != NULL);
650       Reloc_section* rel_dyn = this->rel_dyn_section(layout);
651       Output_data_got<32, false>* got = this->got_section(symtab, layout);
652       unsigned int got_offset = got->add_constant(0);
653       rel_dyn->add_local(object, 0, elfcpp::R_386_TLS_DTPMOD32, got,
654                          got_offset);
655       got->add_constant(0);
656       this->got_mod_index_offset_ = got_offset;
657     }
658   return this->got_mod_index_offset_;
659 }
660
661 // Handle a relocation against a non-function symbol defined in a
662 // dynamic object.  The traditional way to handle this is to generate
663 // a COPY relocation to copy the variable at runtime from the shared
664 // object into the executable's data segment.  However, this is
665 // undesirable in general, as if the size of the object changes in the
666 // dynamic object, the executable will no longer work correctly.  If
667 // this relocation is in a writable section, then we can create a
668 // dynamic reloc and the dynamic linker will resolve it to the correct
669 // address at runtime.  However, we do not want do that if the
670 // relocation is in a read-only section, as it would prevent the
671 // readonly segment from being shared.  And if we have to eventually
672 // generate a COPY reloc, then any dynamic relocations will be
673 // useless.  So this means that if this is a writable section, we need
674 // to save the relocation until we see whether we have to create a
675 // COPY relocation for this symbol for any other relocation.
676
677 void
678 Target_i386::copy_reloc(const General_options* options,
679                         Symbol_table* symtab,
680                         Layout* layout,
681                         Sized_relobj<32, false>* object,
682                         unsigned int data_shndx,
683                         Output_section* output_section,
684                         Symbol* gsym,
685                         const elfcpp::Rel<32, false>& rel)
686 {
687   Sized_symbol<32>* ssym;
688   ssym = symtab->get_sized_symbol SELECT_SIZE_NAME(32) (gsym
689                                                         SELECT_SIZE(32));
690
691   if (!Copy_relocs<32, false>::need_copy_reloc(options, object,
692                                                data_shndx, ssym))
693     {
694       // So far we do not need a COPY reloc.  Save this relocation.
695       // If it turns out that we never need a COPY reloc for this
696       // symbol, then we will emit the relocation.
697       if (this->copy_relocs_ == NULL)
698         this->copy_relocs_ = new Copy_relocs<32, false>();
699       this->copy_relocs_->save(ssym, object, data_shndx, output_section, rel);
700     }
701   else
702     {
703       // Allocate space for this symbol in the .bss section.
704
705       elfcpp::Elf_types<32>::Elf_WXword symsize = ssym->symsize();
706
707       // There is no defined way to determine the required alignment
708       // of the symbol.  We pick the alignment based on the size.  We
709       // set an arbitrary maximum of 256.
710       unsigned int align;
711       for (align = 1; align < 512; align <<= 1)
712         if ((symsize & align) != 0)
713           break;
714
715       if (this->dynbss_ == NULL)
716         {
717           this->dynbss_ = new Output_data_space(align);
718           layout->add_output_section_data(".bss",
719                                           elfcpp::SHT_NOBITS,
720                                           (elfcpp::SHF_ALLOC
721                                            | elfcpp::SHF_WRITE),
722                                           this->dynbss_);
723         }
724
725       Output_data_space* dynbss = this->dynbss_;
726
727       if (align > dynbss->addralign())
728         dynbss->set_space_alignment(align);
729
730       off_t dynbss_size = dynbss->current_data_size();
731       dynbss_size = align_address(dynbss_size, align);
732       off_t offset = dynbss_size;
733       dynbss->set_current_data_size(dynbss_size + symsize);
734
735       symtab->define_with_copy_reloc(this, ssym, dynbss, offset);
736
737       // Add the COPY reloc.
738       Reloc_section* rel_dyn = this->rel_dyn_section(layout);
739       rel_dyn->add_global(ssym, elfcpp::R_386_COPY, dynbss, offset);
740     }
741 }
742
743 // Optimize the TLS relocation type based on what we know about the
744 // symbol.  IS_FINAL is true if the final address of this symbol is
745 // known at link time.
746
747 tls::Tls_optimization
748 Target_i386::optimize_tls_reloc(bool is_final, int r_type)
749 {
750   // If we are generating a shared library, then we can't do anything
751   // in the linker.
752   if (parameters->output_is_shared())
753     return tls::TLSOPT_NONE;
754
755   switch (r_type)
756     {
757     case elfcpp::R_386_TLS_GD:
758     case elfcpp::R_386_TLS_GOTDESC:
759     case elfcpp::R_386_TLS_DESC_CALL:
760       // These are General-Dynamic which permits fully general TLS
761       // access.  Since we know that we are generating an executable,
762       // we can convert this to Initial-Exec.  If we also know that
763       // this is a local symbol, we can further switch to Local-Exec.
764       if (is_final)
765         return tls::TLSOPT_TO_LE;
766       return tls::TLSOPT_TO_IE;
767
768     case elfcpp::R_386_TLS_LDM:
769       // This is Local-Dynamic, which refers to a local symbol in the
770       // dynamic TLS block.  Since we know that we generating an
771       // executable, we can switch to Local-Exec.
772       return tls::TLSOPT_TO_LE;
773
774     case elfcpp::R_386_TLS_LDO_32:
775       // Another type of Local-Dynamic relocation.
776       return tls::TLSOPT_TO_LE;
777
778     case elfcpp::R_386_TLS_IE:
779     case elfcpp::R_386_TLS_GOTIE:
780     case elfcpp::R_386_TLS_IE_32:
781       // These are Initial-Exec relocs which get the thread offset
782       // from the GOT.  If we know that we are linking against the
783       // local symbol, we can switch to Local-Exec, which links the
784       // thread offset into the instruction.
785       if (is_final)
786         return tls::TLSOPT_TO_LE;
787       return tls::TLSOPT_NONE;
788
789     case elfcpp::R_386_TLS_LE:
790     case elfcpp::R_386_TLS_LE_32:
791       // When we already have Local-Exec, there is nothing further we
792       // can do.
793       return tls::TLSOPT_NONE;
794
795     default:
796       gold_unreachable();
797     }
798 }
799
800 // Report an unsupported relocation against a local symbol.
801
802 void
803 Target_i386::Scan::unsupported_reloc_local(Sized_relobj<32, false>* object,
804                                            unsigned int r_type)
805 {
806   gold_error(_("%s: unsupported reloc %u against local symbol"),
807              object->name().c_str(), r_type);
808 }
809
810 // Scan a relocation for a local symbol.
811
812 inline void
813 Target_i386::Scan::local(const General_options&,
814                          Symbol_table* symtab,
815                          Layout* layout,
816                          Target_i386* target,
817                          Sized_relobj<32, false>* object,
818                          unsigned int data_shndx,
819                          Output_section* output_section,
820                          const elfcpp::Rel<32, false>& reloc,
821                          unsigned int r_type,
822                          const elfcpp::Sym<32, false>& lsym)
823 {
824   switch (r_type)
825     {
826     case elfcpp::R_386_NONE:
827     case elfcpp::R_386_GNU_VTINHERIT:
828     case elfcpp::R_386_GNU_VTENTRY:
829       break;
830
831     case elfcpp::R_386_32:
832       // If building a shared library (or a position-independent
833       // executable), we need to create a dynamic relocation for
834       // this location. The relocation applied at link time will
835       // apply the link-time value, so we flag the location with
836       // an R_386_RELATIVE relocation so the dynamic loader can
837       // relocate it easily.
838       if (parameters->output_is_position_independent())
839         {
840           Reloc_section* rel_dyn = target->rel_dyn_section(layout);
841           unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
842           rel_dyn->add_local_relative(object, r_sym, elfcpp::R_386_RELATIVE,
843                                       output_section, data_shndx,
844                                       reloc.get_r_offset());
845         }
846       break;
847
848     case elfcpp::R_386_16:
849     case elfcpp::R_386_8:
850       // If building a shared library (or a position-independent
851       // executable), we need to create a dynamic relocation for
852       // this location. Because the addend needs to remain in the
853       // data section, we need to be careful not to apply this
854       // relocation statically.
855       if (parameters->output_is_position_independent())
856         {
857           Reloc_section* rel_dyn = target->rel_dyn_section(layout);
858           unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
859           rel_dyn->add_local(object, r_sym, r_type, output_section, data_shndx,
860                              reloc.get_r_offset());
861         }
862       break;
863
864     case elfcpp::R_386_PC32:
865     case elfcpp::R_386_PC16:
866     case elfcpp::R_386_PC8:
867       break;
868
869     case elfcpp::R_386_PLT32:
870       // Since we know this is a local symbol, we can handle this as a
871       // PC32 reloc.
872       break;
873
874     case elfcpp::R_386_GOTOFF:
875     case elfcpp::R_386_GOTPC:
876       // We need a GOT section.
877       target->got_section(symtab, layout);
878       break;
879
880     case elfcpp::R_386_GOT32:
881       {
882         // The symbol requires a GOT entry.
883         Output_data_got<32, false>* got = target->got_section(symtab, layout);
884         unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
885         if (got->add_local(object, r_sym))
886           {
887             // If we are generating a shared object, we need to add a
888             // dynamic RELATIVE relocation for this symbol's GOT entry.
889             if (parameters->output_is_position_independent())
890               {
891                 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
892                 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
893                 rel_dyn->add_local_relative(object, r_sym,
894                                             elfcpp::R_386_RELATIVE,
895                                             got,
896                                             object->local_got_offset(r_sym));
897               }
898           }
899       }
900       break;
901
902       // These are relocations which should only be seen by the
903       // dynamic linker, and should never be seen here.
904     case elfcpp::R_386_COPY:
905     case elfcpp::R_386_GLOB_DAT:
906     case elfcpp::R_386_JUMP_SLOT:
907     case elfcpp::R_386_RELATIVE:
908     case elfcpp::R_386_TLS_TPOFF:
909     case elfcpp::R_386_TLS_DTPMOD32:
910     case elfcpp::R_386_TLS_DTPOFF32:
911     case elfcpp::R_386_TLS_TPOFF32:
912     case elfcpp::R_386_TLS_DESC:
913       gold_error(_("%s: unexpected reloc %u in object file"),
914                  object->name().c_str(), r_type);
915       break;
916
917       // These are initial TLS relocs, which are expected when
918       // linking.
919     case elfcpp::R_386_TLS_GD:            // Global-dynamic
920     case elfcpp::R_386_TLS_GOTDESC:       // Global-dynamic (from ~oliva url)
921     case elfcpp::R_386_TLS_DESC_CALL:
922     case elfcpp::R_386_TLS_LDM:           // Local-dynamic
923     case elfcpp::R_386_TLS_LDO_32:        // Alternate local-dynamic
924     case elfcpp::R_386_TLS_IE:            // Initial-exec
925     case elfcpp::R_386_TLS_IE_32:
926     case elfcpp::R_386_TLS_GOTIE:
927     case elfcpp::R_386_TLS_LE:            // Local-exec
928     case elfcpp::R_386_TLS_LE_32:
929       {
930         bool output_is_shared = parameters->output_is_shared();
931         const tls::Tls_optimization optimized_type
932             = Target_i386::optimize_tls_reloc(!output_is_shared, r_type);
933         switch (r_type)
934           {
935           case elfcpp::R_386_TLS_GD:          // Global-dynamic
936             if (optimized_type == tls::TLSOPT_NONE)
937               {
938                 // Create a pair of GOT entries for the module index and
939                 // dtv-relative offset.
940                 Output_data_got<32, false>* got
941                     = target->got_section(symtab, layout);
942                 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
943                 got->add_local_tls_with_rel(object, r_sym, 
944                                             lsym.get_st_shndx(), true,
945                                             target->rel_dyn_section(layout),
946                                             elfcpp::R_386_TLS_DTPMOD32);
947               }
948             else if (optimized_type != tls::TLSOPT_TO_LE)
949               unsupported_reloc_local(object, r_type);
950             break;
951
952           case elfcpp::R_386_TLS_GOTDESC:     // Global-dynamic (from ~oliva)
953           case elfcpp::R_386_TLS_DESC_CALL:
954             // FIXME: If not relaxing to LE, we need to generate
955             // a GOT entry with an R_386_TLS_DESC reloc.
956             if (optimized_type != tls::TLSOPT_TO_LE)
957               unsupported_reloc_local(object, r_type);
958             break;
959
960           case elfcpp::R_386_TLS_LDM:         // Local-dynamic
961             if (optimized_type == tls::TLSOPT_NONE)
962               {
963                 // Create a GOT entry for the module index.
964                 target->got_mod_index_entry(symtab, layout, object);
965               }
966             else if (optimized_type != tls::TLSOPT_TO_LE)
967               unsupported_reloc_local(object, r_type);
968             break;
969
970           case elfcpp::R_386_TLS_LDO_32:      // Alternate local-dynamic
971             break;
972
973           case elfcpp::R_386_TLS_IE:          // Initial-exec
974           case elfcpp::R_386_TLS_IE_32:
975           case elfcpp::R_386_TLS_GOTIE:
976             layout->set_has_static_tls();
977             if (optimized_type == tls::TLSOPT_NONE)
978               {
979                 // For the R_386_TLS_IE relocation, we need to create a
980                 // dynamic relocation when building a shared library.
981                 if (r_type == elfcpp::R_386_TLS_IE
982                     && parameters->output_is_shared())
983                   {
984                     Reloc_section* rel_dyn = target->rel_dyn_section(layout);
985                     unsigned int r_sym
986                         = elfcpp::elf_r_sym<32>(reloc.get_r_info());
987                     rel_dyn->add_local_relative(object, r_sym,
988                                                 elfcpp::R_386_RELATIVE,
989                                                 output_section, data_shndx,
990                                                 reloc.get_r_offset());
991                   }
992                 // Create a GOT entry for the tp-relative offset.
993                 Output_data_got<32, false>* got
994                     = target->got_section(symtab, layout);
995                 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
996                 unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_IE_32
997                                            ? elfcpp::R_386_TLS_TPOFF32
998                                            : elfcpp::R_386_TLS_TPOFF);
999                 got->add_local_with_rel(object, r_sym,
1000                                         target->rel_dyn_section(layout),
1001                                         dyn_r_type);
1002               }
1003             else if (optimized_type != tls::TLSOPT_TO_LE)
1004               unsupported_reloc_local(object, r_type);
1005             break;
1006
1007           case elfcpp::R_386_TLS_LE:          // Local-exec
1008           case elfcpp::R_386_TLS_LE_32:
1009             layout->set_has_static_tls();
1010             if (output_is_shared)
1011               {
1012                 // We need to create a dynamic relocation.
1013                 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1014                 unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_LE_32
1015                                            ? elfcpp::R_386_TLS_TPOFF32
1016                                            : elfcpp::R_386_TLS_TPOFF);
1017                 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1018                 rel_dyn->add_local(object, r_sym, dyn_r_type, output_section,
1019                                    data_shndx, reloc.get_r_offset());
1020               }
1021             break;
1022
1023           default:
1024             gold_unreachable();
1025           }
1026       }
1027       break;
1028
1029     case elfcpp::R_386_32PLT:
1030     case elfcpp::R_386_TLS_GD_32:
1031     case elfcpp::R_386_TLS_GD_PUSH:
1032     case elfcpp::R_386_TLS_GD_CALL:
1033     case elfcpp::R_386_TLS_GD_POP:
1034     case elfcpp::R_386_TLS_LDM_32:
1035     case elfcpp::R_386_TLS_LDM_PUSH:
1036     case elfcpp::R_386_TLS_LDM_CALL:
1037     case elfcpp::R_386_TLS_LDM_POP:
1038     case elfcpp::R_386_USED_BY_INTEL_200:
1039     default:
1040       unsupported_reloc_local(object, r_type);
1041       break;
1042     }
1043 }
1044
1045 // Report an unsupported relocation against a global symbol.
1046
1047 void
1048 Target_i386::Scan::unsupported_reloc_global(Sized_relobj<32, false>* object,
1049                                             unsigned int r_type,
1050                                             Symbol* gsym)
1051 {
1052   gold_error(_("%s: unsupported reloc %u against global symbol %s"),
1053              object->name().c_str(), r_type, gsym->demangled_name().c_str());
1054 }
1055
1056 // Scan a relocation for a global symbol.
1057
1058 inline void
1059 Target_i386::Scan::global(const General_options& options,
1060                           Symbol_table* symtab,
1061                           Layout* layout,
1062                           Target_i386* target,
1063                           Sized_relobj<32, false>* object,
1064                           unsigned int data_shndx,
1065                           Output_section* output_section,
1066                           const elfcpp::Rel<32, false>& reloc,
1067                           unsigned int r_type,
1068                           Symbol* gsym)
1069 {
1070   switch (r_type)
1071     {
1072     case elfcpp::R_386_NONE:
1073     case elfcpp::R_386_GNU_VTINHERIT:
1074     case elfcpp::R_386_GNU_VTENTRY:
1075       break;
1076
1077     case elfcpp::R_386_32:
1078     case elfcpp::R_386_16:
1079     case elfcpp::R_386_8:
1080       {
1081         // Make a PLT entry if necessary.
1082         if (gsym->needs_plt_entry())
1083           {
1084             target->make_plt_entry(symtab, layout, gsym);
1085             // Since this is not a PC-relative relocation, we may be
1086             // taking the address of a function. In that case we need to
1087             // set the entry in the dynamic symbol table to the address of
1088             // the PLT entry.
1089             if (gsym->is_from_dynobj())
1090               gsym->set_needs_dynsym_value();
1091           }
1092         // Make a dynamic relocation if necessary.
1093         if (gsym->needs_dynamic_reloc(true, false))
1094           {
1095             if (target->may_need_copy_reloc(gsym))
1096               {
1097                 target->copy_reloc(&options, symtab, layout, object,
1098                                    data_shndx, output_section, gsym, reloc);
1099               }
1100             else if (r_type == elfcpp::R_386_32
1101                      && gsym->can_use_relative_reloc(false))
1102               {
1103                 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1104                 rel_dyn->add_global_relative(gsym, elfcpp::R_386_RELATIVE,
1105                                              output_section, object,
1106                                              data_shndx, reloc.get_r_offset());
1107               }
1108             else
1109               {
1110                 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1111                 rel_dyn->add_global(gsym, r_type, output_section, object,
1112                                     data_shndx, reloc.get_r_offset());
1113               }
1114           }
1115       }
1116       break;
1117
1118     case elfcpp::R_386_PC32:
1119     case elfcpp::R_386_PC16:
1120     case elfcpp::R_386_PC8:
1121       {
1122         // Make a PLT entry if necessary.
1123         if (gsym->needs_plt_entry())
1124           {
1125             // These relocations are used for function calls only in
1126             // non-PIC code.  For a 32-bit relocation in a shared library,
1127             // we'll need a text relocation anyway, so we can skip the
1128             // PLT entry and let the dynamic linker bind the call directly
1129             // to the target.  For smaller relocations, we should use a
1130             // PLT entry to ensure that the call can reach.
1131             if (!parameters->output_is_shared()
1132                 || r_type != elfcpp::R_386_PC32)
1133               target->make_plt_entry(symtab, layout, gsym);
1134           }
1135         // Make a dynamic relocation if necessary.
1136         bool is_function_call = (gsym->type() == elfcpp::STT_FUNC);
1137         if (gsym->needs_dynamic_reloc(false, is_function_call))
1138           {
1139             if (target->may_need_copy_reloc(gsym))
1140               {
1141                 target->copy_reloc(&options, symtab, layout, object,
1142                                    data_shndx, output_section, gsym, reloc);
1143               }
1144             else
1145               {
1146                 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1147                 rel_dyn->add_global(gsym, r_type, output_section, object,
1148                                     data_shndx, reloc.get_r_offset());
1149               }
1150           }
1151       }
1152       break;
1153
1154     case elfcpp::R_386_GOT32:
1155       {
1156         // The symbol requires a GOT entry.
1157         Output_data_got<32, false>* got = target->got_section(symtab, layout);
1158         if (gsym->final_value_is_known())
1159           got->add_global(gsym);
1160         else
1161           {
1162             // If this symbol is not fully resolved, we need to add a
1163             // GOT entry with a dynamic relocation.
1164             Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1165             if (gsym->is_from_dynobj() || gsym->is_preemptible())
1166               got->add_global_with_rel(gsym, rel_dyn, elfcpp::R_386_GLOB_DAT);
1167             else
1168               {
1169                 if (got->add_global(gsym))
1170                   rel_dyn->add_global_relative(gsym, elfcpp::R_386_RELATIVE,
1171                                                got, gsym->got_offset());
1172               }
1173           }
1174       }
1175       break;
1176
1177     case elfcpp::R_386_PLT32:
1178       // If the symbol is fully resolved, this is just a PC32 reloc.
1179       // Otherwise we need a PLT entry.
1180       if (gsym->final_value_is_known())
1181         break;
1182       // If building a shared library, we can also skip the PLT entry
1183       // if the symbol is defined in the output file and is protected
1184       // or hidden.
1185       if (gsym->is_defined()
1186           && !gsym->is_from_dynobj()
1187           && !gsym->is_preemptible())
1188         break;
1189       target->make_plt_entry(symtab, layout, gsym);
1190       break;
1191
1192     case elfcpp::R_386_GOTOFF:
1193     case elfcpp::R_386_GOTPC:
1194       // We need a GOT section.
1195       target->got_section(symtab, layout);
1196       break;
1197
1198       // These are relocations which should only be seen by the
1199       // dynamic linker, and should never be seen here.
1200     case elfcpp::R_386_COPY:
1201     case elfcpp::R_386_GLOB_DAT:
1202     case elfcpp::R_386_JUMP_SLOT:
1203     case elfcpp::R_386_RELATIVE:
1204     case elfcpp::R_386_TLS_TPOFF:
1205     case elfcpp::R_386_TLS_DTPMOD32:
1206     case elfcpp::R_386_TLS_DTPOFF32:
1207     case elfcpp::R_386_TLS_TPOFF32:
1208     case elfcpp::R_386_TLS_DESC:
1209       gold_error(_("%s: unexpected reloc %u in object file"),
1210                  object->name().c_str(), r_type);
1211       break;
1212
1213       // These are initial tls relocs, which are expected when
1214       // linking.
1215     case elfcpp::R_386_TLS_GD:            // Global-dynamic
1216     case elfcpp::R_386_TLS_GOTDESC:       // Global-dynamic (from ~oliva url)
1217     case elfcpp::R_386_TLS_DESC_CALL:
1218     case elfcpp::R_386_TLS_LDM:           // Local-dynamic
1219     case elfcpp::R_386_TLS_LDO_32:        // Alternate local-dynamic
1220     case elfcpp::R_386_TLS_IE:            // Initial-exec
1221     case elfcpp::R_386_TLS_IE_32:
1222     case elfcpp::R_386_TLS_GOTIE:
1223     case elfcpp::R_386_TLS_LE:            // Local-exec
1224     case elfcpp::R_386_TLS_LE_32:
1225       {
1226         const bool is_final = gsym->final_value_is_known();
1227         const tls::Tls_optimization optimized_type
1228             = Target_i386::optimize_tls_reloc(is_final, r_type);
1229         switch (r_type)
1230           {
1231           case elfcpp::R_386_TLS_GD:          // Global-dynamic
1232             if (optimized_type == tls::TLSOPT_NONE)
1233               {
1234                 // Create a pair of GOT entries for the module index and
1235                 // dtv-relative offset.
1236                 Output_data_got<32, false>* got
1237                     = target->got_section(symtab, layout);
1238                 got->add_global_tls_with_rel(gsym,
1239                                              target->rel_dyn_section(layout),
1240                                              elfcpp::R_386_TLS_DTPMOD32,
1241                                              elfcpp::R_386_TLS_DTPOFF32);
1242               }
1243             else if (optimized_type == tls::TLSOPT_TO_IE)
1244               {
1245                 // Create a GOT entry for the tp-relative offset.
1246                 Output_data_got<32, false>* got
1247                     = target->got_section(symtab, layout);
1248                 got->add_global_with_rel(gsym, target->rel_dyn_section(layout),
1249                                          elfcpp::R_386_TLS_TPOFF32);
1250               }
1251             else if (optimized_type != tls::TLSOPT_TO_LE)
1252               unsupported_reloc_global(object, r_type, gsym);
1253             break;
1254
1255           case elfcpp::R_386_TLS_GOTDESC:     // Global-dynamic (~oliva url)
1256           case elfcpp::R_386_TLS_DESC_CALL:
1257             // FIXME: If not relaxing to LE, we need to generate
1258             // a GOT entry with an R_386_TLS_DESC reloc.
1259             if (optimized_type != tls::TLSOPT_TO_LE)
1260               unsupported_reloc_global(object, r_type, gsym);
1261             unsupported_reloc_global(object, r_type, gsym);
1262             break;
1263
1264           case elfcpp::R_386_TLS_LDM:         // Local-dynamic
1265             if (optimized_type == tls::TLSOPT_NONE)
1266               {
1267                 // Create a GOT entry for the module index.
1268                 target->got_mod_index_entry(symtab, layout, object);
1269               }
1270             else if (optimized_type != tls::TLSOPT_TO_LE)
1271               unsupported_reloc_global(object, r_type, gsym);
1272             break;
1273
1274           case elfcpp::R_386_TLS_LDO_32:      // Alternate local-dynamic
1275             break;
1276
1277           case elfcpp::R_386_TLS_IE:          // Initial-exec
1278           case elfcpp::R_386_TLS_IE_32:
1279           case elfcpp::R_386_TLS_GOTIE:
1280             layout->set_has_static_tls();
1281             if (optimized_type == tls::TLSOPT_NONE)
1282               {
1283                 // For the R_386_TLS_IE relocation, we need to create a
1284                 // dynamic relocation when building a shared library.
1285                 if (r_type == elfcpp::R_386_TLS_IE
1286                     && parameters->output_is_shared())
1287                   {
1288                     Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1289                     rel_dyn->add_global_relative(gsym, elfcpp::R_386_RELATIVE,
1290                                                  output_section, object,
1291                                                  data_shndx,
1292                                                  reloc.get_r_offset());
1293                   }
1294                 // Create a GOT entry for the tp-relative offset.
1295                 Output_data_got<32, false>* got
1296                     = target->got_section(symtab, layout);
1297                 unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_IE_32
1298                                            ? elfcpp::R_386_TLS_TPOFF32
1299                                            : elfcpp::R_386_TLS_TPOFF);
1300                 got->add_global_with_rel(gsym,
1301                                          target->rel_dyn_section(layout),
1302                                          dyn_r_type);
1303               }
1304             else if (optimized_type != tls::TLSOPT_TO_LE)
1305               unsupported_reloc_global(object, r_type, gsym);
1306             break;
1307
1308           case elfcpp::R_386_TLS_LE:          // Local-exec
1309           case elfcpp::R_386_TLS_LE_32:
1310             layout->set_has_static_tls();
1311             if (parameters->output_is_shared())
1312               {
1313                 // We need to create a dynamic relocation.
1314                 unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_LE_32
1315                                            ? elfcpp::R_386_TLS_TPOFF32
1316                                            : elfcpp::R_386_TLS_TPOFF);
1317                 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1318                 rel_dyn->add_global(gsym, dyn_r_type, output_section, object,
1319                                     data_shndx, reloc.get_r_offset());
1320               }
1321             break;
1322
1323           default:
1324             gold_unreachable();
1325           }
1326       }
1327       break;
1328
1329     case elfcpp::R_386_32PLT:
1330     case elfcpp::R_386_TLS_GD_32:
1331     case elfcpp::R_386_TLS_GD_PUSH:
1332     case elfcpp::R_386_TLS_GD_CALL:
1333     case elfcpp::R_386_TLS_GD_POP:
1334     case elfcpp::R_386_TLS_LDM_32:
1335     case elfcpp::R_386_TLS_LDM_PUSH:
1336     case elfcpp::R_386_TLS_LDM_CALL:
1337     case elfcpp::R_386_TLS_LDM_POP:
1338     case elfcpp::R_386_USED_BY_INTEL_200:
1339     default:
1340       unsupported_reloc_global(object, r_type, gsym);
1341       break;
1342     }
1343 }
1344
1345 // Scan relocations for a section.
1346
1347 void
1348 Target_i386::scan_relocs(const General_options& options,
1349                          Symbol_table* symtab,
1350                          Layout* layout,
1351                          Sized_relobj<32, false>* object,
1352                          unsigned int data_shndx,
1353                          unsigned int sh_type,
1354                          const unsigned char* prelocs,
1355                          size_t reloc_count,
1356                          Output_section* output_section,
1357                          bool needs_special_offset_handling,
1358                          size_t local_symbol_count,
1359                          const unsigned char* plocal_symbols)
1360 {
1361   if (sh_type == elfcpp::SHT_RELA)
1362     {
1363       gold_error(_("%s: unsupported RELA reloc section"),
1364                  object->name().c_str());
1365       return;
1366     }
1367
1368   gold::scan_relocs<32, false, Target_i386, elfcpp::SHT_REL,
1369                     Target_i386::Scan>(
1370     options,
1371     symtab,
1372     layout,
1373     this,
1374     object,
1375     data_shndx,
1376     prelocs,
1377     reloc_count,
1378     output_section,
1379     needs_special_offset_handling,
1380     local_symbol_count,
1381     plocal_symbols);
1382 }
1383
1384 // Finalize the sections.
1385
1386 void
1387 Target_i386::do_finalize_sections(Layout* layout)
1388 {
1389   // Fill in some more dynamic tags.
1390   Output_data_dynamic* const odyn = layout->dynamic_data();
1391   if (odyn != NULL)
1392     {
1393       if (this->got_plt_ != NULL)
1394         odyn->add_section_address(elfcpp::DT_PLTGOT, this->got_plt_);
1395
1396       if (this->plt_ != NULL)
1397         {
1398           const Output_data* od = this->plt_->rel_plt();
1399           odyn->add_section_size(elfcpp::DT_PLTRELSZ, od);
1400           odyn->add_section_address(elfcpp::DT_JMPREL, od);
1401           odyn->add_constant(elfcpp::DT_PLTREL, elfcpp::DT_REL);
1402         }
1403
1404       if (this->rel_dyn_ != NULL)
1405         {
1406           const Output_data* od = this->rel_dyn_;
1407           odyn->add_section_address(elfcpp::DT_REL, od);
1408           odyn->add_section_size(elfcpp::DT_RELSZ, od);
1409           odyn->add_constant(elfcpp::DT_RELENT,
1410                              elfcpp::Elf_sizes<32>::rel_size);
1411         }
1412
1413       if (!parameters->output_is_shared())
1414         {
1415           // The value of the DT_DEBUG tag is filled in by the dynamic
1416           // linker at run time, and used by the debugger.
1417           odyn->add_constant(elfcpp::DT_DEBUG, 0);
1418         }
1419     }
1420
1421   // Emit any relocs we saved in an attempt to avoid generating COPY
1422   // relocs.
1423   if (this->copy_relocs_ == NULL)
1424     return;
1425   if (this->copy_relocs_->any_to_emit())
1426     {
1427       Reloc_section* rel_dyn = this->rel_dyn_section(layout);
1428       this->copy_relocs_->emit(rel_dyn);
1429     }
1430   delete this->copy_relocs_;
1431   this->copy_relocs_ = NULL;
1432 }
1433
1434 // Return whether a direct absolute static relocation needs to be applied.
1435 // In cases where Scan::local() or Scan::global() has created
1436 // a dynamic relocation other than R_386_RELATIVE, the addend
1437 // of the relocation is carried in the data, and we must not
1438 // apply the static relocation.
1439
1440 inline bool
1441 Target_i386::Relocate::should_apply_static_reloc(const Sized_symbol<32>* gsym,
1442                                                  bool is_absolute_ref,
1443                                                  bool is_function_call,
1444                                                  bool is_32bit)
1445 {
1446   // For local symbols, we will have created a non-RELATIVE dynamic
1447   // relocation only if (a) the output is position independent,
1448   // (b) the relocation is absolute (not pc- or segment-relative), and
1449   // (c) the relocation is not 32 bits wide.
1450   if (gsym == NULL)
1451     return !(parameters->output_is_position_independent()
1452              && is_absolute_ref
1453              && !is_32bit);
1454
1455   // For global symbols, we use the same helper routines used in the scan pass.
1456   return !(gsym->needs_dynamic_reloc(is_absolute_ref, is_function_call)
1457            && !gsym->can_use_relative_reloc(is_function_call));
1458 }
1459
1460 // Perform a relocation.
1461
1462 inline bool
1463 Target_i386::Relocate::relocate(const Relocate_info<32, false>* relinfo,
1464                                 Target_i386* target,
1465                                 size_t relnum,
1466                                 const elfcpp::Rel<32, false>& rel,
1467                                 unsigned int r_type,
1468                                 const Sized_symbol<32>* gsym,
1469                                 const Symbol_value<32>* psymval,
1470                                 unsigned char* view,
1471                                 elfcpp::Elf_types<32>::Elf_Addr address,
1472                                 off_t view_size)
1473 {
1474   if (this->skip_call_tls_get_addr_)
1475     {
1476       if (r_type != elfcpp::R_386_PLT32
1477           || gsym == NULL
1478           || strcmp(gsym->name(), "___tls_get_addr") != 0)
1479         gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
1480                                _("missing expected TLS relocation"));
1481       else
1482         {
1483           this->skip_call_tls_get_addr_ = false;
1484           return false;
1485         }
1486     }
1487
1488   // Pick the value to use for symbols defined in shared objects.
1489   Symbol_value<32> symval;
1490   if (gsym != NULL
1491       && (gsym->is_from_dynobj()
1492           || (parameters->output_is_shared()
1493               && gsym->is_preemptible()))
1494       && gsym->has_plt_offset())
1495     {
1496       symval.set_output_value(target->plt_section()->address()
1497                               + gsym->plt_offset());
1498       psymval = &symval;
1499     }
1500
1501   const Sized_relobj<32, false>* object = relinfo->object;
1502
1503   // Get the GOT offset if needed.
1504   // The GOT pointer points to the end of the GOT section.
1505   // We need to subtract the size of the GOT section to get
1506   // the actual offset to use in the relocation.
1507   bool have_got_offset = false;
1508   unsigned int got_offset = 0;
1509   switch (r_type)
1510     {
1511     case elfcpp::R_386_GOT32:
1512       if (gsym != NULL)
1513         {
1514           gold_assert(gsym->has_got_offset());
1515           got_offset = gsym->got_offset() - target->got_size();
1516         }
1517       else
1518         {
1519           unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
1520           gold_assert(object->local_has_got_offset(r_sym));
1521           got_offset = object->local_got_offset(r_sym) - target->got_size();
1522         }
1523       have_got_offset = true;
1524       break;
1525
1526     default:
1527       break;
1528     }
1529
1530   switch (r_type)
1531     {
1532     case elfcpp::R_386_NONE:
1533     case elfcpp::R_386_GNU_VTINHERIT:
1534     case elfcpp::R_386_GNU_VTENTRY:
1535       break;
1536
1537     case elfcpp::R_386_32:
1538       if (should_apply_static_reloc(gsym, true, false, true))
1539         Relocate_functions<32, false>::rel32(view, object, psymval);
1540       break;
1541
1542     case elfcpp::R_386_PC32:
1543       {
1544         bool is_function_call = (gsym != NULL
1545                                  && gsym->type() == elfcpp::STT_FUNC);
1546         if (should_apply_static_reloc(gsym, false, is_function_call, true))
1547           Relocate_functions<32, false>::pcrel32(view, object, psymval, address);
1548       }
1549       break;
1550
1551     case elfcpp::R_386_16:
1552       if (should_apply_static_reloc(gsym, true, false, false))
1553         Relocate_functions<32, false>::rel16(view, object, psymval);
1554       break;
1555
1556     case elfcpp::R_386_PC16:
1557       {
1558         bool is_function_call = (gsym != NULL
1559                                  && gsym->type() == elfcpp::STT_FUNC);
1560         if (should_apply_static_reloc(gsym, false, is_function_call, false))
1561           Relocate_functions<32, false>::pcrel32(view, object, psymval, address);
1562       }
1563       break;
1564
1565     case elfcpp::R_386_8:
1566       if (should_apply_static_reloc(gsym, true, false, false))
1567         Relocate_functions<32, false>::rel8(view, object, psymval);
1568       break;
1569
1570     case elfcpp::R_386_PC8:
1571       {
1572         bool is_function_call = (gsym != NULL
1573                                  && gsym->type() == elfcpp::STT_FUNC);
1574         if (should_apply_static_reloc(gsym, false, is_function_call, false))
1575           Relocate_functions<32, false>::pcrel32(view, object, psymval, address);
1576       }
1577       break;
1578
1579     case elfcpp::R_386_PLT32:
1580       gold_assert(gsym == NULL
1581                   || gsym->has_plt_offset()
1582                   || gsym->final_value_is_known());
1583       Relocate_functions<32, false>::pcrel32(view, object, psymval, address);
1584       break;
1585
1586     case elfcpp::R_386_GOT32:
1587       gold_assert(have_got_offset);
1588       Relocate_functions<32, false>::rel32(view, got_offset);
1589       break;
1590
1591     case elfcpp::R_386_GOTOFF:
1592       {
1593         elfcpp::Elf_types<32>::Elf_Addr value;
1594         value = (psymval->value(object, 0)
1595                  - target->got_plt_section()->address());
1596         Relocate_functions<32, false>::rel32(view, value);
1597       }
1598       break;
1599
1600     case elfcpp::R_386_GOTPC:
1601       {
1602         elfcpp::Elf_types<32>::Elf_Addr value;
1603         value = target->got_plt_section()->address();
1604         Relocate_functions<32, false>::pcrel32(view, value, address);
1605       }
1606       break;
1607
1608     case elfcpp::R_386_COPY:
1609     case elfcpp::R_386_GLOB_DAT:
1610     case elfcpp::R_386_JUMP_SLOT:
1611     case elfcpp::R_386_RELATIVE:
1612       // These are outstanding tls relocs, which are unexpected when
1613       // linking.
1614     case elfcpp::R_386_TLS_TPOFF:
1615     case elfcpp::R_386_TLS_DTPMOD32:
1616     case elfcpp::R_386_TLS_DTPOFF32:
1617     case elfcpp::R_386_TLS_TPOFF32:
1618     case elfcpp::R_386_TLS_DESC:
1619       gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
1620                              _("unexpected reloc %u in object file"),
1621                              r_type);
1622       break;
1623
1624       // These are initial tls relocs, which are expected when
1625       // linking.
1626     case elfcpp::R_386_TLS_GD:             // Global-dynamic
1627     case elfcpp::R_386_TLS_GOTDESC:        // Global-dynamic (from ~oliva url)
1628     case elfcpp::R_386_TLS_DESC_CALL:
1629     case elfcpp::R_386_TLS_LDM:            // Local-dynamic
1630     case elfcpp::R_386_TLS_LDO_32:         // Alternate local-dynamic
1631     case elfcpp::R_386_TLS_IE:             // Initial-exec
1632     case elfcpp::R_386_TLS_IE_32:
1633     case elfcpp::R_386_TLS_GOTIE:
1634     case elfcpp::R_386_TLS_LE:             // Local-exec
1635     case elfcpp::R_386_TLS_LE_32:
1636       this->relocate_tls(relinfo, target, relnum, rel, r_type, gsym, psymval,
1637                          view, address, view_size);
1638       break;
1639
1640     case elfcpp::R_386_32PLT:
1641     case elfcpp::R_386_TLS_GD_32:
1642     case elfcpp::R_386_TLS_GD_PUSH:
1643     case elfcpp::R_386_TLS_GD_CALL:
1644     case elfcpp::R_386_TLS_GD_POP:
1645     case elfcpp::R_386_TLS_LDM_32:
1646     case elfcpp::R_386_TLS_LDM_PUSH:
1647     case elfcpp::R_386_TLS_LDM_CALL:
1648     case elfcpp::R_386_TLS_LDM_POP:
1649     case elfcpp::R_386_USED_BY_INTEL_200:
1650     default:
1651       gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
1652                              _("unsupported reloc %u"),
1653                              r_type);
1654       break;
1655     }
1656
1657   return true;
1658 }
1659
1660 // Perform a TLS relocation.
1661
1662 inline void
1663 Target_i386::Relocate::relocate_tls(const Relocate_info<32, false>* relinfo,
1664                                     Target_i386* target,
1665                                     size_t relnum,
1666                                     const elfcpp::Rel<32, false>& rel,
1667                                     unsigned int r_type,
1668                                     const Sized_symbol<32>* gsym,
1669                                     const Symbol_value<32>* psymval,
1670                                     unsigned char* view,
1671                                     elfcpp::Elf_types<32>::Elf_Addr,
1672                                     off_t view_size)
1673 {
1674   Output_segment* tls_segment = relinfo->layout->tls_segment();
1675
1676   const Sized_relobj<32, false>* object = relinfo->object;
1677
1678   elfcpp::Elf_types<32>::Elf_Addr value = psymval->value(object, 0);
1679
1680   const bool is_final = (gsym == NULL
1681                          ? !parameters->output_is_position_independent()
1682                          : gsym->final_value_is_known());
1683   const tls::Tls_optimization optimized_type
1684       = Target_i386::optimize_tls_reloc(is_final, r_type);
1685   switch (r_type)
1686     {
1687     case elfcpp::R_386_TLS_GD:           // Global-dynamic
1688       if (optimized_type == tls::TLSOPT_TO_LE)
1689         {
1690           gold_assert(tls_segment != NULL);
1691           this->tls_gd_to_le(relinfo, relnum, tls_segment,
1692                              rel, r_type, value, view,
1693                              view_size);
1694           break;
1695         }
1696       else
1697         {
1698           unsigned int got_offset;
1699           if (gsym != NULL)
1700             {
1701               gold_assert(gsym->has_tls_got_offset(true));
1702               got_offset = gsym->tls_got_offset(true) - target->got_size();
1703             }
1704           else
1705             {
1706               unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
1707               gold_assert(object->local_has_tls_got_offset(r_sym, true));
1708               got_offset = (object->local_tls_got_offset(r_sym, true)
1709                             - target->got_size());
1710             }
1711           if (optimized_type == tls::TLSOPT_TO_IE)
1712             {
1713               gold_assert(tls_segment != NULL);
1714               this->tls_gd_to_ie(relinfo, relnum, tls_segment, rel, r_type,
1715                                  got_offset, view, view_size);
1716               break;
1717             }
1718           else if (optimized_type == tls::TLSOPT_NONE)
1719             {
1720               // Relocate the field with the offset of the pair of GOT
1721               // entries.
1722               Relocate_functions<32, false>::rel32(view, got_offset);
1723               break;
1724             }
1725         }
1726       gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
1727                              _("unsupported reloc %u"),
1728                              r_type);
1729       break;
1730
1731     case elfcpp::R_386_TLS_GOTDESC:      // Global-dynamic (from ~oliva url)
1732     case elfcpp::R_386_TLS_DESC_CALL:
1733       gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
1734                              _("unsupported reloc %u"),
1735                              r_type);
1736       break;
1737
1738     case elfcpp::R_386_TLS_LDM:          // Local-dynamic
1739       if (this->local_dynamic_type_ == LOCAL_DYNAMIC_SUN)
1740         {
1741           gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
1742                                  _("both SUN and GNU model "
1743                                    "TLS relocations"));
1744           break;
1745         }
1746       this->local_dynamic_type_ = LOCAL_DYNAMIC_GNU;
1747       if (optimized_type == tls::TLSOPT_TO_LE)
1748         {
1749           gold_assert(tls_segment != NULL);
1750           this->tls_ld_to_le(relinfo, relnum, tls_segment, rel, r_type,
1751                              value, view, view_size);
1752           break;
1753         }
1754       else if (optimized_type == tls::TLSOPT_NONE)
1755         {
1756           // Relocate the field with the offset of the GOT entry for
1757           // the module index.
1758           unsigned int got_offset;
1759           got_offset = (target->got_mod_index_entry(NULL, NULL, NULL)
1760                         - target->got_size());
1761           Relocate_functions<32, false>::rel32(view, got_offset);
1762           break;
1763         }
1764       gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
1765                              _("unsupported reloc %u"),
1766                              r_type);
1767       break;
1768
1769     case elfcpp::R_386_TLS_LDO_32:       // Alternate local-dynamic
1770       // This reloc can appear in debugging sections, in which case we
1771       // won't see the TLS_LDM reloc.  The local_dynamic_type field
1772       // tells us this.
1773       if (optimized_type == tls::TLSOPT_TO_LE)
1774         {
1775           gold_assert(tls_segment != NULL);
1776           value -= tls_segment->memsz();
1777         }
1778       Relocate_functions<32, false>::rel32(view, value);
1779       break;
1780
1781     case elfcpp::R_386_TLS_IE:           // Initial-exec
1782     case elfcpp::R_386_TLS_GOTIE:
1783     case elfcpp::R_386_TLS_IE_32:
1784       if (optimized_type == tls::TLSOPT_TO_LE)
1785         {
1786           gold_assert(tls_segment != NULL);
1787           Target_i386::Relocate::tls_ie_to_le(relinfo, relnum, tls_segment,
1788                                               rel, r_type, value, view,
1789                                               view_size);
1790           break;
1791         }
1792       else if (optimized_type == tls::TLSOPT_NONE)
1793         {
1794           // Relocate the field with the offset of the GOT entry for
1795           // the tp-relative offset of the symbol.
1796           unsigned int got_offset;
1797           if (gsym != NULL)
1798             {
1799               gold_assert(gsym->has_got_offset());
1800               got_offset = gsym->got_offset();
1801             }
1802           else
1803             {
1804               unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
1805               gold_assert(object->local_has_got_offset(r_sym));
1806               got_offset = object->local_got_offset(r_sym);
1807             }
1808           // For the R_386_TLS_IE relocation, we need to apply the
1809           // absolute address of the GOT entry.
1810           if (r_type == elfcpp::R_386_TLS_IE)
1811             got_offset += target->got_plt_section()->address();
1812           // All GOT offsets are relative to the end of the GOT.
1813           got_offset -= target->got_size();
1814           Relocate_functions<32, false>::rel32(view, got_offset);
1815           break;
1816         }
1817       gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
1818                              _("unsupported reloc %u"),
1819                              r_type);
1820       break;
1821
1822     case elfcpp::R_386_TLS_LE:           // Local-exec
1823       // If we're creating a shared library, a dynamic relocation will
1824       // have been created for this location, so do not apply it now.
1825       if (!parameters->output_is_shared())
1826         {
1827           gold_assert(tls_segment != NULL);
1828           value -= tls_segment->memsz();
1829           Relocate_functions<32, false>::rel32(view, value);
1830         }
1831       break;
1832
1833     case elfcpp::R_386_TLS_LE_32:
1834       // If we're creating a shared library, a dynamic relocation will
1835       // have been created for this location, so do not apply it now.
1836       if (!parameters->output_is_shared())
1837         {
1838           gold_assert(tls_segment != NULL);
1839           value = tls_segment->memsz() - value;
1840           Relocate_functions<32, false>::rel32(view, value);
1841         }
1842       break;
1843     }
1844 }
1845
1846 // Do a relocation in which we convert a TLS General-Dynamic to a
1847 // Local-Exec.
1848
1849 inline void
1850 Target_i386::Relocate::tls_gd_to_le(const Relocate_info<32, false>* relinfo,
1851                                     size_t relnum,
1852                                     Output_segment* tls_segment,
1853                                     const elfcpp::Rel<32, false>& rel,
1854                                     unsigned int,
1855                                     elfcpp::Elf_types<32>::Elf_Addr value,
1856                                     unsigned char* view,
1857                                     off_t view_size)
1858 {
1859   // leal foo(,%reg,1),%eax; call ___tls_get_addr
1860   //  ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
1861   // leal foo(%reg),%eax; call ___tls_get_addr
1862   //  ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
1863
1864   tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
1865   tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 9);
1866
1867   unsigned char op1 = view[-1];
1868   unsigned char op2 = view[-2];
1869
1870   tls::check_tls(relinfo, relnum, rel.get_r_offset(),
1871                  op2 == 0x8d || op2 == 0x04);
1872   tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[4] == 0xe8);
1873
1874   int roff = 5;
1875
1876   if (op2 == 0x04)
1877     {
1878       tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -3);
1879       tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[-3] == 0x8d);
1880       tls::check_tls(relinfo, relnum, rel.get_r_offset(),
1881                      ((op1 & 0xc7) == 0x05 && op1 != (4 << 3)));
1882       memcpy(view - 3, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
1883     }
1884   else
1885     {
1886       tls::check_tls(relinfo, relnum, rel.get_r_offset(),
1887                      (op1 & 0xf8) == 0x80 && (op1 & 7) != 4);
1888       if (static_cast<off_t>(rel.get_r_offset() + 9) < view_size
1889           && view[9] == 0x90)
1890         {
1891           // There is a trailing nop.  Use the size byte subl.
1892           memcpy(view - 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
1893           roff = 6;
1894         }
1895       else
1896         {
1897           // Use the five byte subl.
1898           memcpy(view - 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
1899         }
1900     }
1901
1902   value = tls_segment->memsz() - value;
1903   Relocate_functions<32, false>::rel32(view + roff, value);
1904
1905   // The next reloc should be a PLT32 reloc against __tls_get_addr.
1906   // We can skip it.
1907   this->skip_call_tls_get_addr_ = true;
1908 }
1909
1910 // Do a relocation in which we convert a TLS General-Dynamic to an
1911 // Initial-Exec.
1912
1913 inline void
1914 Target_i386::Relocate::tls_gd_to_ie(const Relocate_info<32, false>* relinfo,
1915                                     size_t relnum,
1916                                     Output_segment* tls_segment,
1917                                     const elfcpp::Rel<32, false>& rel,
1918                                     unsigned int,
1919                                     elfcpp::Elf_types<32>::Elf_Addr value,
1920                                     unsigned char* view,
1921                                     off_t view_size)
1922 {
1923   // leal foo(,%ebx,1),%eax; call ___tls_get_addr
1924   //  ==> movl %gs:0,%eax; addl foo@gotntpoff(%ebx),%eax
1925
1926   tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
1927   tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 9);
1928
1929   unsigned char op1 = view[-1];
1930   unsigned char op2 = view[-2];
1931
1932   tls::check_tls(relinfo, relnum, rel.get_r_offset(),
1933                  op2 == 0x8d || op2 == 0x04);
1934   tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[4] == 0xe8);
1935
1936   int roff = 5;
1937
1938   // FIXME: For now, support only one form.
1939   tls::check_tls(relinfo, relnum, rel.get_r_offset(),
1940                  op1 == 0x8d && op2 == 0x04);
1941
1942   if (op2 == 0x04)
1943     {
1944       tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -3);
1945       tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[-3] == 0x8d);
1946       tls::check_tls(relinfo, relnum, rel.get_r_offset(),
1947                      ((op1 & 0xc7) == 0x05 && op1 != (4 << 3)));
1948       memcpy(view - 3, "\x65\xa1\0\0\0\0\x03\x83\0\0\0", 12);
1949     }
1950   else
1951     {
1952       tls::check_tls(relinfo, relnum, rel.get_r_offset(),
1953                      (op1 & 0xf8) == 0x80 && (op1 & 7) != 4);
1954       if (static_cast<off_t>(rel.get_r_offset() + 9) < view_size
1955           && view[9] == 0x90)
1956         {
1957           // FIXME: This is not the right instruction sequence.
1958           // There is a trailing nop.  Use the size byte subl.
1959           memcpy(view - 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
1960           roff = 6;
1961         }
1962       else
1963         {
1964           // FIXME: This is not the right instruction sequence.
1965           // Use the five byte subl.
1966           memcpy(view - 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
1967         }
1968     }
1969
1970   value = tls_segment->memsz() - value;
1971   Relocate_functions<32, false>::rel32(view + roff, value);
1972
1973   // The next reloc should be a PLT32 reloc against __tls_get_addr.
1974   // We can skip it.
1975   this->skip_call_tls_get_addr_ = true;
1976 }
1977
1978 // Do a relocation in which we convert a TLS Local-Dynamic to a
1979 // Local-Exec.
1980
1981 inline void
1982 Target_i386::Relocate::tls_ld_to_le(const Relocate_info<32, false>* relinfo,
1983                                     size_t relnum,
1984                                     Output_segment*,
1985                                     const elfcpp::Rel<32, false>& rel,
1986                                     unsigned int,
1987                                     elfcpp::Elf_types<32>::Elf_Addr,
1988                                     unsigned char* view,
1989                                     off_t view_size)
1990 {
1991   // leal foo(%reg), %eax; call ___tls_get_addr
1992   // ==> movl %gs:0,%eax; nop; leal 0(%esi,1),%esi
1993
1994   tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
1995   tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 9);
1996
1997   // FIXME: Does this test really always pass?
1998   tls::check_tls(relinfo, relnum, rel.get_r_offset(),
1999                  view[-2] == 0x8d && view[-1] == 0x83);
2000
2001   tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[4] == 0xe8);
2002
2003   memcpy(view - 2, "\x65\xa1\0\0\0\0\x90\x8d\x74\x26\0", 11);
2004
2005   // The next reloc should be a PLT32 reloc against __tls_get_addr.
2006   // We can skip it.
2007   this->skip_call_tls_get_addr_ = true;
2008 }
2009
2010 // Do a relocation in which we convert a TLS Initial-Exec to a
2011 // Local-Exec.
2012
2013 inline void
2014 Target_i386::Relocate::tls_ie_to_le(const Relocate_info<32, false>* relinfo,
2015                                     size_t relnum,
2016                                     Output_segment* tls_segment,
2017                                     const elfcpp::Rel<32, false>& rel,
2018                                     unsigned int r_type,
2019                                     elfcpp::Elf_types<32>::Elf_Addr value,
2020                                     unsigned char* view,
2021                                     off_t view_size)
2022 {
2023   // We have to actually change the instructions, which means that we
2024   // need to examine the opcodes to figure out which instruction we
2025   // are looking at.
2026   if (r_type == elfcpp::R_386_TLS_IE)
2027     {
2028       // movl %gs:XX,%eax  ==>  movl $YY,%eax
2029       // movl %gs:XX,%reg  ==>  movl $YY,%reg
2030       // addl %gs:XX,%reg  ==>  addl $YY,%reg
2031       tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -1);
2032       tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4);
2033
2034       unsigned char op1 = view[-1];
2035       if (op1 == 0xa1)
2036         {
2037           // movl XX,%eax  ==>  movl $YY,%eax
2038           view[-1] = 0xb8;
2039         }
2040       else
2041         {
2042           tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
2043
2044           unsigned char op2 = view[-2];
2045           if (op2 == 0x8b)
2046             {
2047               // movl XX,%reg  ==>  movl $YY,%reg
2048               tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2049                              (op1 & 0xc7) == 0x05);
2050               view[-2] = 0xc7;
2051               view[-1] = 0xc0 | ((op1 >> 3) & 7);
2052             }
2053           else if (op2 == 0x03)
2054             {
2055               // addl XX,%reg  ==>  addl $YY,%reg
2056               tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2057                              (op1 & 0xc7) == 0x05);
2058               view[-2] = 0x81;
2059               view[-1] = 0xc0 | ((op1 >> 3) & 7);
2060             }
2061           else
2062             tls::check_tls(relinfo, relnum, rel.get_r_offset(), 0);
2063         }
2064     }
2065   else
2066     {
2067       // subl %gs:XX(%reg1),%reg2  ==>  subl $YY,%reg2
2068       // movl %gs:XX(%reg1),%reg2  ==>  movl $YY,%reg2
2069       // addl %gs:XX(%reg1),%reg2  ==>  addl $YY,$reg2
2070       tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
2071       tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4);
2072
2073       unsigned char op1 = view[-1];
2074       unsigned char op2 = view[-2];
2075       tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2076                      (op1 & 0xc0) == 0x80 && (op1 & 7) != 4);
2077       if (op2 == 0x8b)
2078         {
2079           // movl %gs:XX(%reg1),%reg2  ==>  movl $YY,%reg2
2080           view[-2] = 0xc7;
2081           view[-1] = 0xc0 | ((op1 >> 3) & 7);
2082         }
2083       else if (op2 == 0x2b)
2084         {
2085           // subl %gs:XX(%reg1),%reg2  ==>  subl $YY,%reg2
2086           view[-2] = 0x81;
2087           view[-1] = 0xe8 | ((op1 >> 3) & 7);
2088         }
2089       else if (op2 == 0x03)
2090         {
2091           // addl %gs:XX(%reg1),%reg2  ==>  addl $YY,$reg2
2092           view[-2] = 0x81;
2093           view[-1] = 0xc0 | ((op1 >> 3) & 7);
2094         }
2095       else
2096         tls::check_tls(relinfo, relnum, rel.get_r_offset(), 0);
2097     }
2098
2099   value = tls_segment->memsz() - value;
2100   if (r_type == elfcpp::R_386_TLS_IE || r_type == elfcpp::R_386_TLS_GOTIE)
2101     value = - value;
2102
2103   Relocate_functions<32, false>::rel32(view, value);
2104 }
2105
2106 // Relocate section data.
2107
2108 void
2109 Target_i386::relocate_section(const Relocate_info<32, false>* relinfo,
2110                               unsigned int sh_type,
2111                               const unsigned char* prelocs,
2112                               size_t reloc_count,
2113                               Output_section* output_section,
2114                               bool needs_special_offset_handling,
2115                               unsigned char* view,
2116                               elfcpp::Elf_types<32>::Elf_Addr address,
2117                               off_t view_size)
2118 {
2119   gold_assert(sh_type == elfcpp::SHT_REL);
2120
2121   gold::relocate_section<32, false, Target_i386, elfcpp::SHT_REL,
2122                          Target_i386::Relocate>(
2123     relinfo,
2124     this,
2125     prelocs,
2126     reloc_count,
2127     output_section,
2128     needs_special_offset_handling,
2129     view,
2130     address,
2131     view_size);
2132 }
2133
2134 // Return the value to use for a dynamic which requires special
2135 // treatment.  This is how we support equality comparisons of function
2136 // pointers across shared library boundaries, as described in the
2137 // processor specific ABI supplement.
2138
2139 uint64_t
2140 Target_i386::do_dynsym_value(const Symbol* gsym) const
2141 {
2142   gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset());
2143   return this->plt_section()->address() + gsym->plt_offset();
2144 }
2145
2146 // Return a string used to fill a code section with nops to take up
2147 // the specified length.
2148
2149 std::string
2150 Target_i386::do_code_fill(off_t length)
2151 {
2152   if (length >= 16)
2153     {
2154       // Build a jmp instruction to skip over the bytes.
2155       unsigned char jmp[5];
2156       jmp[0] = 0xe9;
2157       elfcpp::Swap_unaligned<32, false>::writeval(jmp + 1, length - 5);
2158       return (std::string(reinterpret_cast<char*>(&jmp[0]), 5)
2159               + std::string(length - 5, '\0'));
2160     }
2161
2162   // Nop sequences of various lengths.
2163   const char nop1[1] = { 0x90 };                   // nop
2164   const char nop2[2] = { 0x66, 0x90 };             // xchg %ax %ax
2165   const char nop3[3] = { 0x8d, 0x76, 0x00 };       // leal 0(%esi),%esi
2166   const char nop4[4] = { 0x8d, 0x74, 0x26, 0x00};  // leal 0(%esi,1),%esi
2167   const char nop5[5] = { 0x90, 0x8d, 0x74, 0x26,   // nop
2168                          0x00 };                   // leal 0(%esi,1),%esi
2169   const char nop6[6] = { 0x8d, 0xb6, 0x00, 0x00,   // leal 0L(%esi),%esi
2170                          0x00, 0x00 };
2171   const char nop7[7] = { 0x8d, 0xb4, 0x26, 0x00,   // leal 0L(%esi,1),%esi
2172                          0x00, 0x00, 0x00 };
2173   const char nop8[8] = { 0x90, 0x8d, 0xb4, 0x26,   // nop
2174                          0x00, 0x00, 0x00, 0x00 }; // leal 0L(%esi,1),%esi
2175   const char nop9[9] = { 0x89, 0xf6, 0x8d, 0xbc,   // movl %esi,%esi
2176                          0x27, 0x00, 0x00, 0x00,   // leal 0L(%edi,1),%edi
2177                          0x00 };
2178   const char nop10[10] = { 0x8d, 0x76, 0x00, 0x8d, // leal 0(%esi),%esi
2179                            0xbc, 0x27, 0x00, 0x00, // leal 0L(%edi,1),%edi
2180                            0x00, 0x00 };
2181   const char nop11[11] = { 0x8d, 0x74, 0x26, 0x00, // leal 0(%esi,1),%esi
2182                            0x8d, 0xbc, 0x27, 0x00, // leal 0L(%edi,1),%edi
2183                            0x00, 0x00, 0x00 };
2184   const char nop12[12] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2185                            0x00, 0x00, 0x8d, 0xbf, // leal 0L(%edi),%edi
2186                            0x00, 0x00, 0x00, 0x00 };
2187   const char nop13[13] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2188                            0x00, 0x00, 0x8d, 0xbc, // leal 0L(%edi,1),%edi
2189                            0x27, 0x00, 0x00, 0x00,
2190                            0x00 };
2191   const char nop14[14] = { 0x8d, 0xb4, 0x26, 0x00, // leal 0L(%esi,1),%esi
2192                            0x00, 0x00, 0x00, 0x8d, // leal 0L(%edi,1),%edi
2193                            0xbc, 0x27, 0x00, 0x00,
2194                            0x00, 0x00 };
2195   const char nop15[15] = { 0xeb, 0x0d, 0x90, 0x90, // jmp .+15
2196                            0x90, 0x90, 0x90, 0x90, // nop,nop,nop,...
2197                            0x90, 0x90, 0x90, 0x90,
2198                            0x90, 0x90, 0x90 };
2199
2200   const char* nops[16] = {
2201     NULL,
2202     nop1, nop2, nop3, nop4, nop5, nop6, nop7,
2203     nop8, nop9, nop10, nop11, nop12, nop13, nop14, nop15
2204   };
2205
2206   return std::string(nops[length], length);
2207 }
2208
2209 // The selector for i386 object files.
2210
2211 class Target_selector_i386 : public Target_selector
2212 {
2213 public:
2214   Target_selector_i386()
2215     : Target_selector(elfcpp::EM_386, 32, false)
2216   { }
2217
2218   Target*
2219   recognize(int machine, int osabi, int abiversion);
2220
2221  private:
2222   Target_i386* target_;
2223 };
2224
2225 // Recognize an i386 object file when we already know that the machine
2226 // number is EM_386.
2227
2228 Target*
2229 Target_selector_i386::recognize(int, int, int)
2230 {
2231   if (this->target_ == NULL)
2232     this->target_ = new Target_i386();
2233   return this->target_;
2234 }
2235
2236 Target_selector_i386 target_selector_i386;
2237
2238 } // End anonymous namespace.