Use relative relocation for R_X86_64_32 on x32
[platform/upstream/binutils.git] / gold / x86_64.cc
1 // x86_64.cc -- x86_64 target support for gold.
2
3 // Copyright 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013
4 // Free Software Foundation, Inc.
5 // Written by Ian Lance Taylor <iant@google.com>.
6
7 // This file is part of gold.
8
9 // This program is free software; you can redistribute it and/or modify
10 // it under the terms of the GNU General Public License as published by
11 // the Free Software Foundation; either version 3 of the License, or
12 // (at your option) any later version.
13
14 // This program is distributed in the hope that it will be useful,
15 // but WITHOUT ANY WARRANTY; without even the implied warranty of
16 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17 // GNU General Public License for more details.
18
19 // You should have received a copy of the GNU General Public License
20 // along with this program; if not, write to the Free Software
21 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
22 // MA 02110-1301, USA.
23
24 #include "gold.h"
25
26 #include <cstring>
27
28 #include "elfcpp.h"
29 #include "dwarf.h"
30 #include "parameters.h"
31 #include "reloc.h"
32 #include "x86_64.h"
33 #include "object.h"
34 #include "symtab.h"
35 #include "layout.h"
36 #include "output.h"
37 #include "copy-relocs.h"
38 #include "target.h"
39 #include "target-reloc.h"
40 #include "target-select.h"
41 #include "tls.h"
42 #include "freebsd.h"
43 #include "nacl.h"
44 #include "gc.h"
45 #include "icf.h"
46
47 namespace
48 {
49
50 using namespace gold;
51
52 // A class to handle the PLT data.
53 // This is an abstract base class that handles most of the linker details
54 // but does not know the actual contents of PLT entries.  The derived
55 // classes below fill in those details.
56
57 template<int size>
58 class Output_data_plt_x86_64 : public Output_section_data
59 {
60  public:
61   typedef Output_data_reloc<elfcpp::SHT_RELA, true, size, false> Reloc_section;
62
63   Output_data_plt_x86_64(Layout* layout, uint64_t addralign,
64                          Output_data_got<64, false>* got,
65                          Output_data_space* got_plt,
66                          Output_data_space* got_irelative)
67     : Output_section_data(addralign), layout_(layout), tlsdesc_rel_(NULL),
68       irelative_rel_(NULL), got_(got), got_plt_(got_plt),
69       got_irelative_(got_irelative), count_(0), irelative_count_(0),
70       tlsdesc_got_offset_(-1U), free_list_()
71   { this->init(layout); }
72
73   Output_data_plt_x86_64(Layout* layout, uint64_t plt_entry_size,
74                          Output_data_got<64, false>* got,
75                          Output_data_space* got_plt,
76                          Output_data_space* got_irelative,
77                          unsigned int plt_count)
78     : Output_section_data((plt_count + 1) * plt_entry_size,
79                           plt_entry_size, false),
80       layout_(layout), tlsdesc_rel_(NULL), irelative_rel_(NULL), got_(got),
81       got_plt_(got_plt), got_irelative_(got_irelative), count_(plt_count),
82       irelative_count_(0), tlsdesc_got_offset_(-1U), free_list_()
83   {
84     this->init(layout);
85
86     // Initialize the free list and reserve the first entry.
87     this->free_list_.init((plt_count + 1) * plt_entry_size, false);
88     this->free_list_.remove(0, plt_entry_size);
89   }
90
91   // Initialize the PLT section.
92   void
93   init(Layout* layout);
94
95   // Add an entry to the PLT.
96   void
97   add_entry(Symbol_table*, Layout*, Symbol* gsym);
98
99   // Add an entry to the PLT for a local STT_GNU_IFUNC symbol.
100   unsigned int
101   add_local_ifunc_entry(Symbol_table* symtab, Layout*,
102                         Sized_relobj_file<size, false>* relobj,
103                         unsigned int local_sym_index);
104
105   // Add the relocation for a PLT entry.
106   void
107   add_relocation(Symbol_table*, Layout*, Symbol* gsym,
108                  unsigned int got_offset);
109
110   // Add the reserved TLSDESC_PLT entry to the PLT.
111   void
112   reserve_tlsdesc_entry(unsigned int got_offset)
113   { this->tlsdesc_got_offset_ = got_offset; }
114
115   // Return true if a TLSDESC_PLT entry has been reserved.
116   bool
117   has_tlsdesc_entry() const
118   { return this->tlsdesc_got_offset_ != -1U; }
119
120   // Return the GOT offset for the reserved TLSDESC_PLT entry.
121   unsigned int
122   get_tlsdesc_got_offset() const
123   { return this->tlsdesc_got_offset_; }
124
125   // Return the offset of the reserved TLSDESC_PLT entry.
126   unsigned int
127   get_tlsdesc_plt_offset() const
128   {
129     return ((this->count_ + this->irelative_count_ + 1)
130             * this->get_plt_entry_size());
131   }
132
133   // Return the .rela.plt section data.
134   Reloc_section*
135   rela_plt()
136   { return this->rel_; }
137
138   // Return where the TLSDESC relocations should go.
139   Reloc_section*
140   rela_tlsdesc(Layout*);
141
142   // Return where the IRELATIVE relocations should go in the PLT
143   // relocations.
144   Reloc_section*
145   rela_irelative(Symbol_table*, Layout*);
146
147   // Return whether we created a section for IRELATIVE relocations.
148   bool
149   has_irelative_section() const
150   { return this->irelative_rel_ != NULL; }
151
152   // Return the number of PLT entries.
153   unsigned int
154   entry_count() const
155   { return this->count_ + this->irelative_count_; }
156
157   // Return the offset of the first non-reserved PLT entry.
158   unsigned int
159   first_plt_entry_offset()
160   { return this->get_plt_entry_size(); }
161
162   // Return the size of a PLT entry.
163   unsigned int
164   get_plt_entry_size() const
165   { return this->do_get_plt_entry_size(); }
166
167   // Reserve a slot in the PLT for an existing symbol in an incremental update.
168   void
169   reserve_slot(unsigned int plt_index)
170   {
171     this->free_list_.remove((plt_index + 1) * this->get_plt_entry_size(),
172                             (plt_index + 2) * this->get_plt_entry_size());
173   }
174
175   // Return the PLT address to use for a global symbol.
176   uint64_t
177   address_for_global(const Symbol*);
178
179   // Return the PLT address to use for a local symbol.
180   uint64_t
181   address_for_local(const Relobj*, unsigned int symndx);
182
183   // Add .eh_frame information for the PLT.
184   void
185   add_eh_frame(Layout* layout)
186   { this->do_add_eh_frame(layout); }
187
188  protected:
189   // Fill in the first PLT entry.
190   void
191   fill_first_plt_entry(unsigned char* pov,
192                        typename elfcpp::Elf_types<size>::Elf_Addr got_address,
193                        typename elfcpp::Elf_types<size>::Elf_Addr plt_address)
194   { this->do_fill_first_plt_entry(pov, got_address, plt_address); }
195
196   // Fill in a normal PLT entry.  Returns the offset into the entry that
197   // should be the initial GOT slot value.
198   unsigned int
199   fill_plt_entry(unsigned char* pov,
200                  typename elfcpp::Elf_types<size>::Elf_Addr got_address,
201                  typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
202                  unsigned int got_offset,
203                  unsigned int plt_offset,
204                  unsigned int plt_index)
205   {
206     return this->do_fill_plt_entry(pov, got_address, plt_address,
207                                    got_offset, plt_offset, plt_index);
208   }
209
210   // Fill in the reserved TLSDESC PLT entry.
211   void
212   fill_tlsdesc_entry(unsigned char* pov,
213                      typename elfcpp::Elf_types<size>::Elf_Addr got_address,
214                      typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
215                      typename elfcpp::Elf_types<size>::Elf_Addr got_base,
216                      unsigned int tlsdesc_got_offset,
217                      unsigned int plt_offset)
218   {
219     this->do_fill_tlsdesc_entry(pov, got_address, plt_address, got_base,
220                                 tlsdesc_got_offset, plt_offset);
221   }
222
223   virtual unsigned int
224   do_get_plt_entry_size() const = 0;
225
226   virtual void
227   do_fill_first_plt_entry(unsigned char* pov,
228                           typename elfcpp::Elf_types<size>::Elf_Addr got_addr,
229                           typename elfcpp::Elf_types<size>::Elf_Addr plt_addr)
230     = 0;
231
232   virtual unsigned int
233   do_fill_plt_entry(unsigned char* pov,
234                     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
235                     typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
236                     unsigned int got_offset,
237                     unsigned int plt_offset,
238                     unsigned int plt_index) = 0;
239
240   virtual void
241   do_fill_tlsdesc_entry(unsigned char* pov,
242                         typename elfcpp::Elf_types<size>::Elf_Addr got_address,
243                         typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
244                         typename elfcpp::Elf_types<size>::Elf_Addr got_base,
245                         unsigned int tlsdesc_got_offset,
246                         unsigned int plt_offset) = 0;
247
248   virtual void
249   do_add_eh_frame(Layout* layout) = 0;
250
251   void
252   do_adjust_output_section(Output_section* os);
253
254   // Write to a map file.
255   void
256   do_print_to_mapfile(Mapfile* mapfile) const
257   { mapfile->print_output_data(this, _("** PLT")); }
258
259   // The CIE of the .eh_frame unwind information for the PLT.
260   static const int plt_eh_frame_cie_size = 16;
261   static const unsigned char plt_eh_frame_cie[plt_eh_frame_cie_size];
262
263  private:
264   // Set the final size.
265   void
266   set_final_data_size();
267
268   // Write out the PLT data.
269   void
270   do_write(Output_file*);
271
272   // A pointer to the Layout class, so that we can find the .dynamic
273   // section when we write out the GOT PLT section.
274   Layout* layout_;
275   // The reloc section.
276   Reloc_section* rel_;
277   // The TLSDESC relocs, if necessary.  These must follow the regular
278   // PLT relocs.
279   Reloc_section* tlsdesc_rel_;
280   // The IRELATIVE relocs, if necessary.  These must follow the
281   // regular PLT relocations and the TLSDESC relocations.
282   Reloc_section* irelative_rel_;
283   // The .got section.
284   Output_data_got<64, false>* got_;
285   // The .got.plt section.
286   Output_data_space* got_plt_;
287   // The part of the .got.plt section used for IRELATIVE relocs.
288   Output_data_space* got_irelative_;
289   // The number of PLT entries.
290   unsigned int count_;
291   // Number of PLT entries with R_X86_64_IRELATIVE relocs.  These
292   // follow the regular PLT entries.
293   unsigned int irelative_count_;
294   // Offset of the reserved TLSDESC_GOT entry when needed.
295   unsigned int tlsdesc_got_offset_;
296   // List of available regions within the section, for incremental
297   // update links.
298   Free_list free_list_;
299 };
300
301 template<int size>
302 class Output_data_plt_x86_64_standard : public Output_data_plt_x86_64<size>
303 {
304  public:
305   Output_data_plt_x86_64_standard(Layout* layout,
306                                   Output_data_got<64, false>* got,
307                                   Output_data_space* got_plt,
308                                   Output_data_space* got_irelative)
309     : Output_data_plt_x86_64<size>(layout, plt_entry_size,
310                                    got, got_plt, got_irelative)
311   { }
312
313   Output_data_plt_x86_64_standard(Layout* layout,
314                                   Output_data_got<64, false>* got,
315                                   Output_data_space* got_plt,
316                                   Output_data_space* got_irelative,
317                                   unsigned int plt_count)
318     : Output_data_plt_x86_64<size>(layout, plt_entry_size,
319                                    got, got_plt, got_irelative,
320                                    plt_count)
321   { }
322
323  protected:
324   virtual unsigned int
325   do_get_plt_entry_size() const
326   { return plt_entry_size; }
327
328   virtual void
329   do_add_eh_frame(Layout* layout)
330   {
331     layout->add_eh_frame_for_plt(this,
332                                  this->plt_eh_frame_cie,
333                                  this->plt_eh_frame_cie_size,
334                                  plt_eh_frame_fde,
335                                  plt_eh_frame_fde_size);
336   }
337
338   virtual void
339   do_fill_first_plt_entry(unsigned char* pov,
340                           typename elfcpp::Elf_types<size>::Elf_Addr got_addr,
341                           typename elfcpp::Elf_types<size>::Elf_Addr plt_addr);
342
343   virtual unsigned int
344   do_fill_plt_entry(unsigned char* pov,
345                     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
346                     typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
347                     unsigned int got_offset,
348                     unsigned int plt_offset,
349                     unsigned int plt_index);
350
351   virtual void
352   do_fill_tlsdesc_entry(unsigned char* pov,
353                         typename elfcpp::Elf_types<size>::Elf_Addr got_address,
354                         typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
355                         typename elfcpp::Elf_types<size>::Elf_Addr got_base,
356                         unsigned int tlsdesc_got_offset,
357                         unsigned int plt_offset);
358
359  private:
360   // The size of an entry in the PLT.
361   static const int plt_entry_size = 16;
362
363   // The first entry in the PLT.
364   // From the AMD64 ABI: "Unlike Intel386 ABI, this ABI uses the same
365   // procedure linkage table for both programs and shared objects."
366   static const unsigned char first_plt_entry[plt_entry_size];
367
368   // Other entries in the PLT for an executable.
369   static const unsigned char plt_entry[plt_entry_size];
370
371   // The reserved TLSDESC entry in the PLT for an executable.
372   static const unsigned char tlsdesc_plt_entry[plt_entry_size];
373
374   // The .eh_frame unwind information for the PLT.
375   static const int plt_eh_frame_fde_size = 32;
376   static const unsigned char plt_eh_frame_fde[plt_eh_frame_fde_size];
377 };
378
379 // The x86_64 target class.
380 // See the ABI at
381 //   http://www.x86-64.org/documentation/abi.pdf
382 // TLS info comes from
383 //   http://people.redhat.com/drepper/tls.pdf
384 //   http://www.lsd.ic.unicamp.br/~oliva/writeups/TLS/RFC-TLSDESC-x86.txt
385
386 template<int size>
387 class Target_x86_64 : public Sized_target<size, false>
388 {
389  public:
390   // In the x86_64 ABI (p 68), it says "The AMD64 ABI architectures
391   // uses only Elf64_Rela relocation entries with explicit addends."
392   typedef Output_data_reloc<elfcpp::SHT_RELA, true, size, false> Reloc_section;
393
394   Target_x86_64(const Target::Target_info* info = &x86_64_info)
395     : Sized_target<size, false>(info),
396       got_(NULL), plt_(NULL), got_plt_(NULL), got_irelative_(NULL),
397       got_tlsdesc_(NULL), global_offset_table_(NULL), rela_dyn_(NULL),
398       rela_irelative_(NULL), copy_relocs_(elfcpp::R_X86_64_COPY),
399       dynbss_(NULL), got_mod_index_offset_(-1U), tlsdesc_reloc_info_(),
400       tls_base_symbol_defined_(false)
401   { }
402
403   // Hook for a new output section.
404   void
405   do_new_output_section(Output_section*) const;
406
407   // Scan the relocations to look for symbol adjustments.
408   void
409   gc_process_relocs(Symbol_table* symtab,
410                     Layout* layout,
411                     Sized_relobj_file<size, false>* object,
412                     unsigned int data_shndx,
413                     unsigned int sh_type,
414                     const unsigned char* prelocs,
415                     size_t reloc_count,
416                     Output_section* output_section,
417                     bool needs_special_offset_handling,
418                     size_t local_symbol_count,
419                     const unsigned char* plocal_symbols);
420
421   // Scan the relocations to look for symbol adjustments.
422   void
423   scan_relocs(Symbol_table* symtab,
424               Layout* layout,
425               Sized_relobj_file<size, false>* object,
426               unsigned int data_shndx,
427               unsigned int sh_type,
428               const unsigned char* prelocs,
429               size_t reloc_count,
430               Output_section* output_section,
431               bool needs_special_offset_handling,
432               size_t local_symbol_count,
433               const unsigned char* plocal_symbols);
434
435   // Finalize the sections.
436   void
437   do_finalize_sections(Layout*, const Input_objects*, Symbol_table*);
438
439   // Return the value to use for a dynamic which requires special
440   // treatment.
441   uint64_t
442   do_dynsym_value(const Symbol*) const;
443
444   // Relocate a section.
445   void
446   relocate_section(const Relocate_info<size, false>*,
447                    unsigned int sh_type,
448                    const unsigned char* prelocs,
449                    size_t reloc_count,
450                    Output_section* output_section,
451                    bool needs_special_offset_handling,
452                    unsigned char* view,
453                    typename elfcpp::Elf_types<size>::Elf_Addr view_address,
454                    section_size_type view_size,
455                    const Reloc_symbol_changes*);
456
457   // Scan the relocs during a relocatable link.
458   void
459   scan_relocatable_relocs(Symbol_table* symtab,
460                           Layout* layout,
461                           Sized_relobj_file<size, false>* object,
462                           unsigned int data_shndx,
463                           unsigned int sh_type,
464                           const unsigned char* prelocs,
465                           size_t reloc_count,
466                           Output_section* output_section,
467                           bool needs_special_offset_handling,
468                           size_t local_symbol_count,
469                           const unsigned char* plocal_symbols,
470                           Relocatable_relocs*);
471
472   // Emit relocations for a section.
473   void
474   relocate_relocs(
475       const Relocate_info<size, false>*,
476       unsigned int sh_type,
477       const unsigned char* prelocs,
478       size_t reloc_count,
479       Output_section* output_section,
480       typename elfcpp::Elf_types<size>::Elf_Off offset_in_output_section,
481       const Relocatable_relocs*,
482       unsigned char* view,
483       typename elfcpp::Elf_types<size>::Elf_Addr view_address,
484       section_size_type view_size,
485       unsigned char* reloc_view,
486       section_size_type reloc_view_size);
487
488   // Return a string used to fill a code section with nops.
489   std::string
490   do_code_fill(section_size_type length) const;
491
492   // Return whether SYM is defined by the ABI.
493   bool
494   do_is_defined_by_abi(const Symbol* sym) const
495   { return strcmp(sym->name(), "__tls_get_addr") == 0; }
496
497   // Return the symbol index to use for a target specific relocation.
498   // The only target specific relocation is R_X86_64_TLSDESC for a
499   // local symbol, which is an absolute reloc.
500   unsigned int
501   do_reloc_symbol_index(void*, unsigned int r_type) const
502   {
503     gold_assert(r_type == elfcpp::R_X86_64_TLSDESC);
504     return 0;
505   }
506
507   // Return the addend to use for a target specific relocation.
508   uint64_t
509   do_reloc_addend(void* arg, unsigned int r_type, uint64_t addend) const;
510
511   // Return the PLT section.
512   uint64_t
513   do_plt_address_for_global(const Symbol* gsym) const
514   { return this->plt_section()->address_for_global(gsym); }
515
516   uint64_t
517   do_plt_address_for_local(const Relobj* relobj, unsigned int symndx) const
518   { return this->plt_section()->address_for_local(relobj, symndx); }
519
520   // This function should be defined in targets that can use relocation
521   // types to determine (implemented in local_reloc_may_be_function_pointer
522   // and global_reloc_may_be_function_pointer)
523   // if a function's pointer is taken.  ICF uses this in safe mode to only
524   // fold those functions whose pointer is defintely not taken.  For x86_64
525   // pie binaries, safe ICF cannot be done by looking at relocation types.
526   bool
527   do_can_check_for_function_pointers() const
528   { return !parameters->options().pie(); }
529
530   // Return the base for a DW_EH_PE_datarel encoding.
531   uint64_t
532   do_ehframe_datarel_base() const;
533
534   // Adjust -fsplit-stack code which calls non-split-stack code.
535   void
536   do_calls_non_split(Relobj* object, unsigned int shndx,
537                      section_offset_type fnoffset, section_size_type fnsize,
538                      unsigned char* view, section_size_type view_size,
539                      std::string* from, std::string* to) const;
540
541   // Return the size of the GOT section.
542   section_size_type
543   got_size() const
544   {
545     gold_assert(this->got_ != NULL);
546     return this->got_->data_size();
547   }
548
549   // Return the number of entries in the GOT.
550   unsigned int
551   got_entry_count() const
552   {
553     if (this->got_ == NULL)
554       return 0;
555     return this->got_size() / 8;
556   }
557
558   // Return the number of entries in the PLT.
559   unsigned int
560   plt_entry_count() const;
561
562   // Return the offset of the first non-reserved PLT entry.
563   unsigned int
564   first_plt_entry_offset() const;
565
566   // Return the size of each PLT entry.
567   unsigned int
568   plt_entry_size() const;
569
570   // Create the GOT section for an incremental update.
571   Output_data_got_base*
572   init_got_plt_for_update(Symbol_table* symtab,
573                           Layout* layout,
574                           unsigned int got_count,
575                           unsigned int plt_count);
576
577   // Reserve a GOT entry for a local symbol, and regenerate any
578   // necessary dynamic relocations.
579   void
580   reserve_local_got_entry(unsigned int got_index,
581                           Sized_relobj<size, false>* obj,
582                           unsigned int r_sym,
583                           unsigned int got_type);
584
585   // Reserve a GOT entry for a global symbol, and regenerate any
586   // necessary dynamic relocations.
587   void
588   reserve_global_got_entry(unsigned int got_index, Symbol* gsym,
589                            unsigned int got_type);
590
591   // Register an existing PLT entry for a global symbol.
592   void
593   register_global_plt_entry(Symbol_table*, Layout*, unsigned int plt_index,
594                             Symbol* gsym);
595
596   // Force a COPY relocation for a given symbol.
597   void
598   emit_copy_reloc(Symbol_table*, Symbol*, Output_section*, off_t);
599
600   // Apply an incremental relocation.
601   void
602   apply_relocation(const Relocate_info<size, false>* relinfo,
603                    typename elfcpp::Elf_types<size>::Elf_Addr r_offset,
604                    unsigned int r_type,
605                    typename elfcpp::Elf_types<size>::Elf_Swxword r_addend,
606                    const Symbol* gsym,
607                    unsigned char* view,
608                    typename elfcpp::Elf_types<size>::Elf_Addr address,
609                    section_size_type view_size);
610
611   // Add a new reloc argument, returning the index in the vector.
612   size_t
613   add_tlsdesc_info(Sized_relobj_file<size, false>* object, unsigned int r_sym)
614   {
615     this->tlsdesc_reloc_info_.push_back(Tlsdesc_info(object, r_sym));
616     return this->tlsdesc_reloc_info_.size() - 1;
617   }
618
619   Output_data_plt_x86_64<size>*
620   make_data_plt(Layout* layout,
621                 Output_data_got<64, false>* got,
622                 Output_data_space* got_plt,
623                 Output_data_space* got_irelative)
624   {
625     return this->do_make_data_plt(layout, got, got_plt, got_irelative);
626   }
627
628   Output_data_plt_x86_64<size>*
629   make_data_plt(Layout* layout,
630                 Output_data_got<64, false>* got,
631                 Output_data_space* got_plt,
632                 Output_data_space* got_irelative,
633                 unsigned int plt_count)
634   {
635     return this->do_make_data_plt(layout, got, got_plt, got_irelative,
636                                   plt_count);
637   }
638
639   virtual Output_data_plt_x86_64<size>*
640   do_make_data_plt(Layout* layout,
641                    Output_data_got<64, false>* got,
642                    Output_data_space* got_plt,
643                    Output_data_space* got_irelative)
644   {
645     return new Output_data_plt_x86_64_standard<size>(layout, got, got_plt,
646                                                      got_irelative);
647   }
648
649   virtual Output_data_plt_x86_64<size>*
650   do_make_data_plt(Layout* layout,
651                    Output_data_got<64, false>* got,
652                    Output_data_space* got_plt,
653                    Output_data_space* got_irelative,
654                    unsigned int plt_count)
655   {
656     return new Output_data_plt_x86_64_standard<size>(layout, got, got_plt,
657                                                      got_irelative,
658                                                      plt_count);
659   }
660
661  private:
662   // The class which scans relocations.
663   class Scan
664   {
665   public:
666     Scan()
667       : issued_non_pic_error_(false)
668     { }
669
670     static inline int
671     get_reference_flags(unsigned int r_type);
672
673     inline void
674     local(Symbol_table* symtab, Layout* layout, Target_x86_64* target,
675           Sized_relobj_file<size, false>* object,
676           unsigned int data_shndx,
677           Output_section* output_section,
678           const elfcpp::Rela<size, false>& reloc, unsigned int r_type,
679           const elfcpp::Sym<size, false>& lsym,
680           bool is_discarded);
681
682     inline void
683     global(Symbol_table* symtab, Layout* layout, Target_x86_64* target,
684            Sized_relobj_file<size, false>* object,
685            unsigned int data_shndx,
686            Output_section* output_section,
687            const elfcpp::Rela<size, false>& reloc, unsigned int r_type,
688            Symbol* gsym);
689
690     inline bool
691     local_reloc_may_be_function_pointer(Symbol_table* symtab, Layout* layout,
692                                         Target_x86_64* target,
693                                         Sized_relobj_file<size, false>* object,
694                                         unsigned int data_shndx,
695                                         Output_section* output_section,
696                                         const elfcpp::Rela<size, false>& reloc,
697                                         unsigned int r_type,
698                                         const elfcpp::Sym<size, false>& lsym);
699
700     inline bool
701     global_reloc_may_be_function_pointer(Symbol_table* symtab, Layout* layout,
702                                          Target_x86_64* target,
703                                          Sized_relobj_file<size, false>* object,
704                                          unsigned int data_shndx,
705                                          Output_section* output_section,
706                                          const elfcpp::Rela<size, false>& reloc,
707                                          unsigned int r_type,
708                                          Symbol* gsym);
709
710   private:
711     static void
712     unsupported_reloc_local(Sized_relobj_file<size, false>*,
713                             unsigned int r_type);
714
715     static void
716     unsupported_reloc_global(Sized_relobj_file<size, false>*,
717                              unsigned int r_type, Symbol*);
718
719     void
720     check_non_pic(Relobj*, unsigned int r_type, Symbol*);
721
722     inline bool
723     possible_function_pointer_reloc(unsigned int r_type);
724
725     bool
726     reloc_needs_plt_for_ifunc(Sized_relobj_file<size, false>*,
727                               unsigned int r_type);
728
729     // Whether we have issued an error about a non-PIC compilation.
730     bool issued_non_pic_error_;
731   };
732
733   // The class which implements relocation.
734   class Relocate
735   {
736    public:
737     Relocate()
738       : skip_call_tls_get_addr_(false)
739     { }
740
741     ~Relocate()
742     {
743       if (this->skip_call_tls_get_addr_)
744         {
745           // FIXME: This needs to specify the location somehow.
746           gold_error(_("missing expected TLS relocation"));
747         }
748     }
749
750     // Do a relocation.  Return false if the caller should not issue
751     // any warnings about this relocation.
752     inline bool
753     relocate(const Relocate_info<size, false>*, Target_x86_64*,
754              Output_section*,
755              size_t relnum, const elfcpp::Rela<size, false>&,
756              unsigned int r_type, const Sized_symbol<size>*,
757              const Symbol_value<size>*,
758              unsigned char*, typename elfcpp::Elf_types<size>::Elf_Addr,
759              section_size_type);
760
761    private:
762     // Do a TLS relocation.
763     inline void
764     relocate_tls(const Relocate_info<size, false>*, Target_x86_64*,
765                  size_t relnum, const elfcpp::Rela<size, false>&,
766                  unsigned int r_type, const Sized_symbol<size>*,
767                  const Symbol_value<size>*,
768                  unsigned char*, typename elfcpp::Elf_types<size>::Elf_Addr,
769                  section_size_type);
770
771     // Do a TLS General-Dynamic to Initial-Exec transition.
772     inline void
773     tls_gd_to_ie(const Relocate_info<size, false>*, size_t relnum,
774                  Output_segment* tls_segment,
775                  const elfcpp::Rela<size, false>&, unsigned int r_type,
776                  typename elfcpp::Elf_types<size>::Elf_Addr value,
777                  unsigned char* view,
778                  typename elfcpp::Elf_types<size>::Elf_Addr,
779                  section_size_type view_size);
780
781     // Do a TLS General-Dynamic to Local-Exec transition.
782     inline void
783     tls_gd_to_le(const Relocate_info<size, false>*, size_t relnum,
784                  Output_segment* tls_segment,
785                  const elfcpp::Rela<size, false>&, unsigned int r_type,
786                  typename elfcpp::Elf_types<size>::Elf_Addr value,
787                  unsigned char* view,
788                  section_size_type view_size);
789
790     // Do a TLSDESC-style General-Dynamic to Initial-Exec transition.
791     inline void
792     tls_desc_gd_to_ie(const Relocate_info<size, false>*, size_t relnum,
793                       Output_segment* tls_segment,
794                       const elfcpp::Rela<size, false>&, unsigned int r_type,
795                       typename elfcpp::Elf_types<size>::Elf_Addr value,
796                       unsigned char* view,
797                       typename elfcpp::Elf_types<size>::Elf_Addr,
798                       section_size_type view_size);
799
800     // Do a TLSDESC-style General-Dynamic to Local-Exec transition.
801     inline void
802     tls_desc_gd_to_le(const Relocate_info<size, false>*, size_t relnum,
803                       Output_segment* tls_segment,
804                       const elfcpp::Rela<size, false>&, unsigned int r_type,
805                       typename elfcpp::Elf_types<size>::Elf_Addr value,
806                       unsigned char* view,
807                       section_size_type view_size);
808
809     // Do a TLS Local-Dynamic to Local-Exec transition.
810     inline void
811     tls_ld_to_le(const Relocate_info<size, false>*, size_t relnum,
812                  Output_segment* tls_segment,
813                  const elfcpp::Rela<size, false>&, unsigned int r_type,
814                  typename elfcpp::Elf_types<size>::Elf_Addr value,
815                  unsigned char* view,
816                  section_size_type view_size);
817
818     // Do a TLS Initial-Exec to Local-Exec transition.
819     static inline void
820     tls_ie_to_le(const Relocate_info<size, false>*, size_t relnum,
821                  Output_segment* tls_segment,
822                  const elfcpp::Rela<size, false>&, unsigned int r_type,
823                  typename elfcpp::Elf_types<size>::Elf_Addr value,
824                  unsigned char* view,
825                  section_size_type view_size);
826
827     // This is set if we should skip the next reloc, which should be a
828     // PLT32 reloc against ___tls_get_addr.
829     bool skip_call_tls_get_addr_;
830   };
831
832   // A class which returns the size required for a relocation type,
833   // used while scanning relocs during a relocatable link.
834   class Relocatable_size_for_reloc
835   {
836    public:
837     unsigned int
838     get_size_for_reloc(unsigned int, Relobj*);
839   };
840
841   // Adjust TLS relocation type based on the options and whether this
842   // is a local symbol.
843   static tls::Tls_optimization
844   optimize_tls_reloc(bool is_final, int r_type);
845
846   // Get the GOT section, creating it if necessary.
847   Output_data_got<64, false>*
848   got_section(Symbol_table*, Layout*);
849
850   // Get the GOT PLT section.
851   Output_data_space*
852   got_plt_section() const
853   {
854     gold_assert(this->got_plt_ != NULL);
855     return this->got_plt_;
856   }
857
858   // Get the GOT section for TLSDESC entries.
859   Output_data_got<64, false>*
860   got_tlsdesc_section() const
861   {
862     gold_assert(this->got_tlsdesc_ != NULL);
863     return this->got_tlsdesc_;
864   }
865
866   // Create the PLT section.
867   void
868   make_plt_section(Symbol_table* symtab, Layout* layout);
869
870   // Create a PLT entry for a global symbol.
871   void
872   make_plt_entry(Symbol_table*, Layout*, Symbol*);
873
874   // Create a PLT entry for a local STT_GNU_IFUNC symbol.
875   void
876   make_local_ifunc_plt_entry(Symbol_table*, Layout*,
877                              Sized_relobj_file<size, false>* relobj,
878                              unsigned int local_sym_index);
879
880   // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
881   void
882   define_tls_base_symbol(Symbol_table*, Layout*);
883
884   // Create the reserved PLT and GOT entries for the TLS descriptor resolver.
885   void
886   reserve_tlsdesc_entries(Symbol_table* symtab, Layout* layout);
887
888   // Create a GOT entry for the TLS module index.
889   unsigned int
890   got_mod_index_entry(Symbol_table* symtab, Layout* layout,
891                       Sized_relobj_file<size, false>* object);
892
893   // Get the PLT section.
894   Output_data_plt_x86_64<size>*
895   plt_section() const
896   {
897     gold_assert(this->plt_ != NULL);
898     return this->plt_;
899   }
900
901   // Get the dynamic reloc section, creating it if necessary.
902   Reloc_section*
903   rela_dyn_section(Layout*);
904
905   // Get the section to use for TLSDESC relocations.
906   Reloc_section*
907   rela_tlsdesc_section(Layout*) const;
908
909   // Get the section to use for IRELATIVE relocations.
910   Reloc_section*
911   rela_irelative_section(Layout*);
912
913   // Add a potential copy relocation.
914   void
915   copy_reloc(Symbol_table* symtab, Layout* layout,
916              Sized_relobj_file<size, false>* object,
917              unsigned int shndx, Output_section* output_section,
918              Symbol* sym, const elfcpp::Rela<size, false>& reloc)
919   {
920     this->copy_relocs_.copy_reloc(symtab, layout,
921                                   symtab->get_sized_symbol<size>(sym),
922                                   object, shndx, output_section,
923                                   reloc, this->rela_dyn_section(layout));
924   }
925
926   // Information about this specific target which we pass to the
927   // general Target structure.
928   static const Target::Target_info x86_64_info;
929
930   // The types of GOT entries needed for this platform.
931   // These values are exposed to the ABI in an incremental link.
932   // Do not renumber existing values without changing the version
933   // number of the .gnu_incremental_inputs section.
934   enum Got_type
935   {
936     GOT_TYPE_STANDARD = 0,      // GOT entry for a regular symbol
937     GOT_TYPE_TLS_OFFSET = 1,    // GOT entry for TLS offset
938     GOT_TYPE_TLS_PAIR = 2,      // GOT entry for TLS module/offset pair
939     GOT_TYPE_TLS_DESC = 3       // GOT entry for TLS_DESC pair
940   };
941
942   // This type is used as the argument to the target specific
943   // relocation routines.  The only target specific reloc is
944   // R_X86_64_TLSDESC against a local symbol.
945   struct Tlsdesc_info
946   {
947     Tlsdesc_info(Sized_relobj_file<size, false>* a_object, unsigned int a_r_sym)
948       : object(a_object), r_sym(a_r_sym)
949     { }
950
951     // The object in which the local symbol is defined.
952     Sized_relobj_file<size, false>* object;
953     // The local symbol index in the object.
954     unsigned int r_sym;
955   };
956
957   // The GOT section.
958   Output_data_got<64, false>* got_;
959   // The PLT section.
960   Output_data_plt_x86_64<size>* plt_;
961   // The GOT PLT section.
962   Output_data_space* got_plt_;
963   // The GOT section for IRELATIVE relocations.
964   Output_data_space* got_irelative_;
965   // The GOT section for TLSDESC relocations.
966   Output_data_got<64, false>* got_tlsdesc_;
967   // The _GLOBAL_OFFSET_TABLE_ symbol.
968   Symbol* global_offset_table_;
969   // The dynamic reloc section.
970   Reloc_section* rela_dyn_;
971   // The section to use for IRELATIVE relocs.
972   Reloc_section* rela_irelative_;
973   // Relocs saved to avoid a COPY reloc.
974   Copy_relocs<elfcpp::SHT_RELA, size, false> copy_relocs_;
975   // Space for variables copied with a COPY reloc.
976   Output_data_space* dynbss_;
977   // Offset of the GOT entry for the TLS module index.
978   unsigned int got_mod_index_offset_;
979   // We handle R_X86_64_TLSDESC against a local symbol as a target
980   // specific relocation.  Here we store the object and local symbol
981   // index for the relocation.
982   std::vector<Tlsdesc_info> tlsdesc_reloc_info_;
983   // True if the _TLS_MODULE_BASE_ symbol has been defined.
984   bool tls_base_symbol_defined_;
985 };
986
987 template<>
988 const Target::Target_info Target_x86_64<64>::x86_64_info =
989 {
990   64,                   // size
991   false,                // is_big_endian
992   elfcpp::EM_X86_64,    // machine_code
993   false,                // has_make_symbol
994   false,                // has_resolve
995   true,                 // has_code_fill
996   true,                 // is_default_stack_executable
997   true,                 // can_icf_inline_merge_sections
998   '\0',                 // wrap_char
999   "/lib/ld64.so.1",     // program interpreter
1000   0x400000,             // default_text_segment_address
1001   0x1000,               // abi_pagesize (overridable by -z max-page-size)
1002   0x1000,               // common_pagesize (overridable by -z common-page-size)
1003   false,                // isolate_execinstr
1004   0,                    // rosegment_gap
1005   elfcpp::SHN_UNDEF,    // small_common_shndx
1006   elfcpp::SHN_X86_64_LCOMMON,   // large_common_shndx
1007   0,                    // small_common_section_flags
1008   elfcpp::SHF_X86_64_LARGE,     // large_common_section_flags
1009   NULL,                 // attributes_section
1010   NULL,                 // attributes_vendor
1011   "_start"              // entry_symbol_name
1012 };
1013
1014 template<>
1015 const Target::Target_info Target_x86_64<32>::x86_64_info =
1016 {
1017   32,                   // size
1018   false,                // is_big_endian
1019   elfcpp::EM_X86_64,    // machine_code
1020   false,                // has_make_symbol
1021   false,                // has_resolve
1022   true,                 // has_code_fill
1023   true,                 // is_default_stack_executable
1024   true,                 // can_icf_inline_merge_sections
1025   '\0',                 // wrap_char
1026   "/libx32/ldx32.so.1", // program interpreter
1027   0x400000,             // default_text_segment_address
1028   0x1000,               // abi_pagesize (overridable by -z max-page-size)
1029   0x1000,               // common_pagesize (overridable by -z common-page-size)
1030   false,                // isolate_execinstr
1031   0,                    // rosegment_gap
1032   elfcpp::SHN_UNDEF,    // small_common_shndx
1033   elfcpp::SHN_X86_64_LCOMMON,   // large_common_shndx
1034   0,                    // small_common_section_flags
1035   elfcpp::SHF_X86_64_LARGE,     // large_common_section_flags
1036   NULL,                 // attributes_section
1037   NULL,                 // attributes_vendor
1038   "_start"              // entry_symbol_name
1039 };
1040
1041 // This is called when a new output section is created.  This is where
1042 // we handle the SHF_X86_64_LARGE.
1043
1044 template<int size>
1045 void
1046 Target_x86_64<size>::do_new_output_section(Output_section* os) const
1047 {
1048   if ((os->flags() & elfcpp::SHF_X86_64_LARGE) != 0)
1049     os->set_is_large_section();
1050 }
1051
1052 // Get the GOT section, creating it if necessary.
1053
1054 template<int size>
1055 Output_data_got<64, false>*
1056 Target_x86_64<size>::got_section(Symbol_table* symtab, Layout* layout)
1057 {
1058   if (this->got_ == NULL)
1059     {
1060       gold_assert(symtab != NULL && layout != NULL);
1061
1062       // When using -z now, we can treat .got.plt as a relro section.
1063       // Without -z now, it is modified after program startup by lazy
1064       // PLT relocations.
1065       bool is_got_plt_relro = parameters->options().now();
1066       Output_section_order got_order = (is_got_plt_relro
1067                                         ? ORDER_RELRO
1068                                         : ORDER_RELRO_LAST);
1069       Output_section_order got_plt_order = (is_got_plt_relro
1070                                             ? ORDER_RELRO
1071                                             : ORDER_NON_RELRO_FIRST);
1072
1073       this->got_ = new Output_data_got<64, false>();
1074
1075       layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
1076                                       (elfcpp::SHF_ALLOC
1077                                        | elfcpp::SHF_WRITE),
1078                                       this->got_, got_order, true);
1079
1080       this->got_plt_ = new Output_data_space(8, "** GOT PLT");
1081       layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
1082                                       (elfcpp::SHF_ALLOC
1083                                        | elfcpp::SHF_WRITE),
1084                                       this->got_plt_, got_plt_order,
1085                                       is_got_plt_relro);
1086
1087       // The first three entries are reserved.
1088       this->got_plt_->set_current_data_size(3 * 8);
1089
1090       if (!is_got_plt_relro)
1091         {
1092           // Those bytes can go into the relro segment.
1093           layout->increase_relro(3 * 8);
1094         }
1095
1096       // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
1097       this->global_offset_table_ =
1098         symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
1099                                       Symbol_table::PREDEFINED,
1100                                       this->got_plt_,
1101                                       0, 0, elfcpp::STT_OBJECT,
1102                                       elfcpp::STB_LOCAL,
1103                                       elfcpp::STV_HIDDEN, 0,
1104                                       false, false);
1105
1106       // If there are any IRELATIVE relocations, they get GOT entries
1107       // in .got.plt after the jump slot entries.
1108       this->got_irelative_ = new Output_data_space(8, "** GOT IRELATIVE PLT");
1109       layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
1110                                       (elfcpp::SHF_ALLOC
1111                                        | elfcpp::SHF_WRITE),
1112                                       this->got_irelative_,
1113                                       got_plt_order, is_got_plt_relro);
1114
1115       // If there are any TLSDESC relocations, they get GOT entries in
1116       // .got.plt after the jump slot and IRELATIVE entries.
1117       this->got_tlsdesc_ = new Output_data_got<64, false>();
1118       layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
1119                                       (elfcpp::SHF_ALLOC
1120                                        | elfcpp::SHF_WRITE),
1121                                       this->got_tlsdesc_,
1122                                       got_plt_order, is_got_plt_relro);
1123     }
1124
1125   return this->got_;
1126 }
1127
1128 // Get the dynamic reloc section, creating it if necessary.
1129
1130 template<int size>
1131 typename Target_x86_64<size>::Reloc_section*
1132 Target_x86_64<size>::rela_dyn_section(Layout* layout)
1133 {
1134   if (this->rela_dyn_ == NULL)
1135     {
1136       gold_assert(layout != NULL);
1137       this->rela_dyn_ = new Reloc_section(parameters->options().combreloc());
1138       layout->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA,
1139                                       elfcpp::SHF_ALLOC, this->rela_dyn_,
1140                                       ORDER_DYNAMIC_RELOCS, false);
1141     }
1142   return this->rela_dyn_;
1143 }
1144
1145 // Get the section to use for IRELATIVE relocs, creating it if
1146 // necessary.  These go in .rela.dyn, but only after all other dynamic
1147 // relocations.  They need to follow the other dynamic relocations so
1148 // that they can refer to global variables initialized by those
1149 // relocs.
1150
1151 template<int size>
1152 typename Target_x86_64<size>::Reloc_section*
1153 Target_x86_64<size>::rela_irelative_section(Layout* layout)
1154 {
1155   if (this->rela_irelative_ == NULL)
1156     {
1157       // Make sure we have already created the dynamic reloc section.
1158       this->rela_dyn_section(layout);
1159       this->rela_irelative_ = new Reloc_section(false);
1160       layout->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA,
1161                                       elfcpp::SHF_ALLOC, this->rela_irelative_,
1162                                       ORDER_DYNAMIC_RELOCS, false);
1163       gold_assert(this->rela_dyn_->output_section()
1164                   == this->rela_irelative_->output_section());
1165     }
1166   return this->rela_irelative_;
1167 }
1168
1169 // Initialize the PLT section.
1170
1171 template<int size>
1172 void
1173 Output_data_plt_x86_64<size>::init(Layout* layout)
1174 {
1175   this->rel_ = new Reloc_section(false);
1176   layout->add_output_section_data(".rela.plt", elfcpp::SHT_RELA,
1177                                   elfcpp::SHF_ALLOC, this->rel_,
1178                                   ORDER_DYNAMIC_PLT_RELOCS, false);
1179 }
1180
1181 template<int size>
1182 void
1183 Output_data_plt_x86_64<size>::do_adjust_output_section(Output_section* os)
1184 {
1185   os->set_entsize(this->get_plt_entry_size());
1186 }
1187
1188 // Add an entry to the PLT.
1189
1190 template<int size>
1191 void
1192 Output_data_plt_x86_64<size>::add_entry(Symbol_table* symtab, Layout* layout,
1193                                         Symbol* gsym)
1194 {
1195   gold_assert(!gsym->has_plt_offset());
1196
1197   unsigned int plt_index;
1198   off_t plt_offset;
1199   section_offset_type got_offset;
1200
1201   unsigned int* pcount;
1202   unsigned int offset;
1203   unsigned int reserved;
1204   Output_data_space* got;
1205   if (gsym->type() == elfcpp::STT_GNU_IFUNC
1206       && gsym->can_use_relative_reloc(false))
1207     {
1208       pcount = &this->irelative_count_;
1209       offset = 0;
1210       reserved = 0;
1211       got = this->got_irelative_;
1212     }
1213   else
1214     {
1215       pcount = &this->count_;
1216       offset = 1;
1217       reserved = 3;
1218       got = this->got_plt_;
1219     }
1220
1221   if (!this->is_data_size_valid())
1222     {
1223       // Note that when setting the PLT offset for a non-IRELATIVE
1224       // entry we skip the initial reserved PLT entry.
1225       plt_index = *pcount + offset;
1226       plt_offset = plt_index * this->get_plt_entry_size();
1227
1228       ++*pcount;
1229
1230       got_offset = (plt_index - offset + reserved) * 8;
1231       gold_assert(got_offset == got->current_data_size());
1232
1233       // Every PLT entry needs a GOT entry which points back to the PLT
1234       // entry (this will be changed by the dynamic linker, normally
1235       // lazily when the function is called).
1236       got->set_current_data_size(got_offset + 8);
1237     }
1238   else
1239     {
1240       // FIXME: This is probably not correct for IRELATIVE relocs.
1241
1242       // For incremental updates, find an available slot.
1243       plt_offset = this->free_list_.allocate(this->get_plt_entry_size(),
1244                                              this->get_plt_entry_size(), 0);
1245       if (plt_offset == -1)
1246         gold_fallback(_("out of patch space (PLT);"
1247                         " relink with --incremental-full"));
1248
1249       // The GOT and PLT entries have a 1-1 correspondance, so the GOT offset
1250       // can be calculated from the PLT index, adjusting for the three
1251       // reserved entries at the beginning of the GOT.
1252       plt_index = plt_offset / this->get_plt_entry_size() - 1;
1253       got_offset = (plt_index - offset + reserved) * 8;
1254     }
1255
1256   gsym->set_plt_offset(plt_offset);
1257
1258   // Every PLT entry needs a reloc.
1259   this->add_relocation(symtab, layout, gsym, got_offset);
1260
1261   // Note that we don't need to save the symbol.  The contents of the
1262   // PLT are independent of which symbols are used.  The symbols only
1263   // appear in the relocations.
1264 }
1265
1266 // Add an entry to the PLT for a local STT_GNU_IFUNC symbol.  Return
1267 // the PLT offset.
1268
1269 template<int size>
1270 unsigned int
1271 Output_data_plt_x86_64<size>::add_local_ifunc_entry(
1272     Symbol_table* symtab,
1273     Layout* layout,
1274     Sized_relobj_file<size, false>* relobj,
1275     unsigned int local_sym_index)
1276 {
1277   unsigned int plt_offset = this->irelative_count_ * this->get_plt_entry_size();
1278   ++this->irelative_count_;
1279
1280   section_offset_type got_offset = this->got_irelative_->current_data_size();
1281
1282   // Every PLT entry needs a GOT entry which points back to the PLT
1283   // entry.
1284   this->got_irelative_->set_current_data_size(got_offset + 8);
1285
1286   // Every PLT entry needs a reloc.
1287   Reloc_section* rela = this->rela_irelative(symtab, layout);
1288   rela->add_symbolless_local_addend(relobj, local_sym_index,
1289                                     elfcpp::R_X86_64_IRELATIVE,
1290                                     this->got_irelative_, got_offset, 0);
1291
1292   return plt_offset;
1293 }
1294
1295 // Add the relocation for a PLT entry.
1296
1297 template<int size>
1298 void
1299 Output_data_plt_x86_64<size>::add_relocation(Symbol_table* symtab,
1300                                              Layout* layout,
1301                                              Symbol* gsym,
1302                                              unsigned int got_offset)
1303 {
1304   if (gsym->type() == elfcpp::STT_GNU_IFUNC
1305       && gsym->can_use_relative_reloc(false))
1306     {
1307       Reloc_section* rela = this->rela_irelative(symtab, layout);
1308       rela->add_symbolless_global_addend(gsym, elfcpp::R_X86_64_IRELATIVE,
1309                                          this->got_irelative_, got_offset, 0);
1310     }
1311   else
1312     {
1313       gsym->set_needs_dynsym_entry();
1314       this->rel_->add_global(gsym, elfcpp::R_X86_64_JUMP_SLOT, this->got_plt_,
1315                              got_offset, 0);
1316     }
1317 }
1318
1319 // Return where the TLSDESC relocations should go, creating it if
1320 // necessary.  These follow the JUMP_SLOT relocations.
1321
1322 template<int size>
1323 typename Output_data_plt_x86_64<size>::Reloc_section*
1324 Output_data_plt_x86_64<size>::rela_tlsdesc(Layout* layout)
1325 {
1326   if (this->tlsdesc_rel_ == NULL)
1327     {
1328       this->tlsdesc_rel_ = new Reloc_section(false);
1329       layout->add_output_section_data(".rela.plt", elfcpp::SHT_RELA,
1330                                       elfcpp::SHF_ALLOC, this->tlsdesc_rel_,
1331                                       ORDER_DYNAMIC_PLT_RELOCS, false);
1332       gold_assert(this->tlsdesc_rel_->output_section()
1333                   == this->rel_->output_section());
1334     }
1335   return this->tlsdesc_rel_;
1336 }
1337
1338 // Return where the IRELATIVE relocations should go in the PLT.  These
1339 // follow the JUMP_SLOT and the TLSDESC relocations.
1340
1341 template<int size>
1342 typename Output_data_plt_x86_64<size>::Reloc_section*
1343 Output_data_plt_x86_64<size>::rela_irelative(Symbol_table* symtab,
1344                                              Layout* layout)
1345 {
1346   if (this->irelative_rel_ == NULL)
1347     {
1348       // Make sure we have a place for the TLSDESC relocations, in
1349       // case we see any later on.
1350       this->rela_tlsdesc(layout);
1351       this->irelative_rel_ = new Reloc_section(false);
1352       layout->add_output_section_data(".rela.plt", elfcpp::SHT_RELA,
1353                                       elfcpp::SHF_ALLOC, this->irelative_rel_,
1354                                       ORDER_DYNAMIC_PLT_RELOCS, false);
1355       gold_assert(this->irelative_rel_->output_section()
1356                   == this->rel_->output_section());
1357
1358       if (parameters->doing_static_link())
1359         {
1360           // A statically linked executable will only have a .rela.plt
1361           // section to hold R_X86_64_IRELATIVE relocs for
1362           // STT_GNU_IFUNC symbols.  The library will use these
1363           // symbols to locate the IRELATIVE relocs at program startup
1364           // time.
1365           symtab->define_in_output_data("__rela_iplt_start", NULL,
1366                                         Symbol_table::PREDEFINED,
1367                                         this->irelative_rel_, 0, 0,
1368                                         elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL,
1369                                         elfcpp::STV_HIDDEN, 0, false, true);
1370           symtab->define_in_output_data("__rela_iplt_end", NULL,
1371                                         Symbol_table::PREDEFINED,
1372                                         this->irelative_rel_, 0, 0,
1373                                         elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL,
1374                                         elfcpp::STV_HIDDEN, 0, true, true);
1375         }
1376     }
1377   return this->irelative_rel_;
1378 }
1379
1380 // Return the PLT address to use for a global symbol.
1381
1382 template<int size>
1383 uint64_t
1384 Output_data_plt_x86_64<size>::address_for_global(const Symbol* gsym)
1385 {
1386   uint64_t offset = 0;
1387   if (gsym->type() == elfcpp::STT_GNU_IFUNC
1388       && gsym->can_use_relative_reloc(false))
1389     offset = (this->count_ + 1) * this->get_plt_entry_size();
1390   return this->address() + offset + gsym->plt_offset();
1391 }
1392
1393 // Return the PLT address to use for a local symbol.  These are always
1394 // IRELATIVE relocs.
1395
1396 template<int size>
1397 uint64_t
1398 Output_data_plt_x86_64<size>::address_for_local(const Relobj* object,
1399                                                 unsigned int r_sym)
1400 {
1401   return (this->address()
1402           + (this->count_ + 1) * this->get_plt_entry_size()
1403           + object->local_plt_offset(r_sym));
1404 }
1405
1406 // Set the final size.
1407 template<int size>
1408 void
1409 Output_data_plt_x86_64<size>::set_final_data_size()
1410 {
1411   unsigned int count = this->count_ + this->irelative_count_;
1412   if (this->has_tlsdesc_entry())
1413     ++count;
1414   this->set_data_size((count + 1) * this->get_plt_entry_size());
1415 }
1416
1417 // The first entry in the PLT for an executable.
1418
1419 template<int size>
1420 const unsigned char
1421 Output_data_plt_x86_64_standard<size>::first_plt_entry[plt_entry_size] =
1422 {
1423   // From AMD64 ABI Draft 0.98, page 76
1424   0xff, 0x35,   // pushq contents of memory address
1425   0, 0, 0, 0,   // replaced with address of .got + 8
1426   0xff, 0x25,   // jmp indirect
1427   0, 0, 0, 0,   // replaced with address of .got + 16
1428   0x90, 0x90, 0x90, 0x90   // noop (x4)
1429 };
1430
1431 template<int size>
1432 void
1433 Output_data_plt_x86_64_standard<size>::do_fill_first_plt_entry(
1434     unsigned char* pov,
1435     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
1436     typename elfcpp::Elf_types<size>::Elf_Addr plt_address)
1437 {
1438   memcpy(pov, first_plt_entry, plt_entry_size);
1439   // We do a jmp relative to the PC at the end of this instruction.
1440   elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
1441                                               (got_address + 8
1442                                                - (plt_address + 6)));
1443   elfcpp::Swap<32, false>::writeval(pov + 8,
1444                                     (got_address + 16
1445                                      - (plt_address + 12)));
1446 }
1447
1448 // Subsequent entries in the PLT for an executable.
1449
1450 template<int size>
1451 const unsigned char
1452 Output_data_plt_x86_64_standard<size>::plt_entry[plt_entry_size] =
1453 {
1454   // From AMD64 ABI Draft 0.98, page 76
1455   0xff, 0x25,   // jmpq indirect
1456   0, 0, 0, 0,   // replaced with address of symbol in .got
1457   0x68,         // pushq immediate
1458   0, 0, 0, 0,   // replaced with offset into relocation table
1459   0xe9,         // jmpq relative
1460   0, 0, 0, 0    // replaced with offset to start of .plt
1461 };
1462
1463 template<int size>
1464 unsigned int
1465 Output_data_plt_x86_64_standard<size>::do_fill_plt_entry(
1466     unsigned char* pov,
1467     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
1468     typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
1469     unsigned int got_offset,
1470     unsigned int plt_offset,
1471     unsigned int plt_index)
1472 {
1473   memcpy(pov, plt_entry, plt_entry_size);
1474   elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
1475                                               (got_address + got_offset
1476                                                - (plt_address + plt_offset
1477                                                   + 6)));
1478
1479   elfcpp::Swap_unaligned<32, false>::writeval(pov + 7, plt_index);
1480   elfcpp::Swap<32, false>::writeval(pov + 12,
1481                                     - (plt_offset + plt_entry_size));
1482
1483   return 6;
1484 }
1485
1486 // The reserved TLSDESC entry in the PLT for an executable.
1487
1488 template<int size>
1489 const unsigned char
1490 Output_data_plt_x86_64_standard<size>::tlsdesc_plt_entry[plt_entry_size] =
1491 {
1492   // From Alexandre Oliva, "Thread-Local Storage Descriptors for IA32
1493   // and AMD64/EM64T", Version 0.9.4 (2005-10-10).
1494   0xff, 0x35,   // pushq x(%rip)
1495   0, 0, 0, 0,   // replaced with address of linkmap GOT entry (at PLTGOT + 8)
1496   0xff, 0x25,   // jmpq *y(%rip)
1497   0, 0, 0, 0,   // replaced with offset of reserved TLSDESC_GOT entry
1498   0x0f, 0x1f,   // nop
1499   0x40, 0
1500 };
1501
1502 template<int size>
1503 void
1504 Output_data_plt_x86_64_standard<size>::do_fill_tlsdesc_entry(
1505     unsigned char* pov,
1506     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
1507     typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
1508     typename elfcpp::Elf_types<size>::Elf_Addr got_base,
1509     unsigned int tlsdesc_got_offset,
1510     unsigned int plt_offset)
1511 {
1512   memcpy(pov, tlsdesc_plt_entry, plt_entry_size);
1513   elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
1514                                               (got_address + 8
1515                                                - (plt_address + plt_offset
1516                                                   + 6)));
1517   elfcpp::Swap_unaligned<32, false>::writeval(pov + 8,
1518                                               (got_base
1519                                                + tlsdesc_got_offset
1520                                                - (plt_address + plt_offset
1521                                                   + 12)));
1522 }
1523
1524 // The .eh_frame unwind information for the PLT.
1525
1526 template<int size>
1527 const unsigned char
1528 Output_data_plt_x86_64<size>::plt_eh_frame_cie[plt_eh_frame_cie_size] =
1529 {
1530   1,                            // CIE version.
1531   'z',                          // Augmentation: augmentation size included.
1532   'R',                          // Augmentation: FDE encoding included.
1533   '\0',                         // End of augmentation string.
1534   1,                            // Code alignment factor.
1535   0x78,                         // Data alignment factor.
1536   16,                           // Return address column.
1537   1,                            // Augmentation size.
1538   (elfcpp::DW_EH_PE_pcrel       // FDE encoding.
1539    | elfcpp::DW_EH_PE_sdata4),
1540   elfcpp::DW_CFA_def_cfa, 7, 8, // DW_CFA_def_cfa: r7 (rsp) ofs 8.
1541   elfcpp::DW_CFA_offset + 16, 1,// DW_CFA_offset: r16 (rip) at cfa-8.
1542   elfcpp::DW_CFA_nop,           // Align to 16 bytes.
1543   elfcpp::DW_CFA_nop
1544 };
1545
1546 template<int size>
1547 const unsigned char
1548 Output_data_plt_x86_64_standard<size>::plt_eh_frame_fde[plt_eh_frame_fde_size] =
1549 {
1550   0, 0, 0, 0,                           // Replaced with offset to .plt.
1551   0, 0, 0, 0,                           // Replaced with size of .plt.
1552   0,                                    // Augmentation size.
1553   elfcpp::DW_CFA_def_cfa_offset, 16,    // DW_CFA_def_cfa_offset: 16.
1554   elfcpp::DW_CFA_advance_loc + 6,       // Advance 6 to __PLT__ + 6.
1555   elfcpp::DW_CFA_def_cfa_offset, 24,    // DW_CFA_def_cfa_offset: 24.
1556   elfcpp::DW_CFA_advance_loc + 10,      // Advance 10 to __PLT__ + 16.
1557   elfcpp::DW_CFA_def_cfa_expression,    // DW_CFA_def_cfa_expression.
1558   11,                                   // Block length.
1559   elfcpp::DW_OP_breg7, 8,               // Push %rsp + 8.
1560   elfcpp::DW_OP_breg16, 0,              // Push %rip.
1561   elfcpp::DW_OP_lit15,                  // Push 0xf.
1562   elfcpp::DW_OP_and,                    // & (%rip & 0xf).
1563   elfcpp::DW_OP_lit11,                  // Push 0xb.
1564   elfcpp::DW_OP_ge,                     // >= ((%rip & 0xf) >= 0xb)
1565   elfcpp::DW_OP_lit3,                   // Push 3.
1566   elfcpp::DW_OP_shl,                    // << (((%rip & 0xf) >= 0xb) << 3)
1567   elfcpp::DW_OP_plus,                   // + ((((%rip&0xf)>=0xb)<<3)+%rsp+8
1568   elfcpp::DW_CFA_nop,                   // Align to 32 bytes.
1569   elfcpp::DW_CFA_nop,
1570   elfcpp::DW_CFA_nop,
1571   elfcpp::DW_CFA_nop
1572 };
1573
1574 // Write out the PLT.  This uses the hand-coded instructions above,
1575 // and adjusts them as needed.  This is specified by the AMD64 ABI.
1576
1577 template<int size>
1578 void
1579 Output_data_plt_x86_64<size>::do_write(Output_file* of)
1580 {
1581   const off_t offset = this->offset();
1582   const section_size_type oview_size =
1583     convert_to_section_size_type(this->data_size());
1584   unsigned char* const oview = of->get_output_view(offset, oview_size);
1585
1586   const off_t got_file_offset = this->got_plt_->offset();
1587   gold_assert(parameters->incremental_update()
1588               || (got_file_offset + this->got_plt_->data_size()
1589                   == this->got_irelative_->offset()));
1590   const section_size_type got_size =
1591     convert_to_section_size_type(this->got_plt_->data_size()
1592                                  + this->got_irelative_->data_size());
1593   unsigned char* const got_view = of->get_output_view(got_file_offset,
1594                                                       got_size);
1595
1596   unsigned char* pov = oview;
1597
1598   // The base address of the .plt section.
1599   typename elfcpp::Elf_types<size>::Elf_Addr plt_address = this->address();
1600   // The base address of the .got section.
1601   typename elfcpp::Elf_types<size>::Elf_Addr got_base = this->got_->address();
1602   // The base address of the PLT portion of the .got section,
1603   // which is where the GOT pointer will point, and where the
1604   // three reserved GOT entries are located.
1605   typename elfcpp::Elf_types<size>::Elf_Addr got_address
1606     = this->got_plt_->address();
1607
1608   this->fill_first_plt_entry(pov, got_address, plt_address);
1609   pov += this->get_plt_entry_size();
1610
1611   unsigned char* got_pov = got_view;
1612
1613   // The first entry in the GOT is the address of the .dynamic section
1614   // aka the PT_DYNAMIC segment.  The next two entries are reserved.
1615   // We saved space for them when we created the section in
1616   // Target_x86_64::got_section.
1617   Output_section* dynamic = this->layout_->dynamic_section();
1618   uint32_t dynamic_addr = dynamic == NULL ? 0 : dynamic->address();
1619   elfcpp::Swap<64, false>::writeval(got_pov, dynamic_addr);
1620   got_pov += 8;
1621   memset(got_pov, 0, 16);
1622   got_pov += 16;
1623
1624   unsigned int plt_offset = this->get_plt_entry_size();
1625   unsigned int got_offset = 24;
1626   const unsigned int count = this->count_ + this->irelative_count_;
1627   for (unsigned int plt_index = 0;
1628        plt_index < count;
1629        ++plt_index,
1630          pov += this->get_plt_entry_size(),
1631          got_pov += 8,
1632          plt_offset += this->get_plt_entry_size(),
1633          got_offset += 8)
1634     {
1635       // Set and adjust the PLT entry itself.
1636       unsigned int lazy_offset = this->fill_plt_entry(pov,
1637                                                       got_address, plt_address,
1638                                                       got_offset, plt_offset,
1639                                                       plt_index);
1640
1641       // Set the entry in the GOT.
1642       elfcpp::Swap<64, false>::writeval(got_pov,
1643                                         plt_address + plt_offset + lazy_offset);
1644     }
1645
1646   if (this->has_tlsdesc_entry())
1647     {
1648       // Set and adjust the reserved TLSDESC PLT entry.
1649       unsigned int tlsdesc_got_offset = this->get_tlsdesc_got_offset();
1650       this->fill_tlsdesc_entry(pov, got_address, plt_address, got_base,
1651                                tlsdesc_got_offset, plt_offset);
1652       pov += this->get_plt_entry_size();
1653     }
1654
1655   gold_assert(static_cast<section_size_type>(pov - oview) == oview_size);
1656   gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size);
1657
1658   of->write_output_view(offset, oview_size, oview);
1659   of->write_output_view(got_file_offset, got_size, got_view);
1660 }
1661
1662 // Create the PLT section.
1663
1664 template<int size>
1665 void
1666 Target_x86_64<size>::make_plt_section(Symbol_table* symtab, Layout* layout)
1667 {
1668   if (this->plt_ == NULL)
1669     {
1670       // Create the GOT sections first.
1671       this->got_section(symtab, layout);
1672
1673       this->plt_ = this->make_data_plt(layout, this->got_, this->got_plt_,
1674                                        this->got_irelative_);
1675
1676       // Add unwind information if requested.
1677       if (parameters->options().ld_generated_unwind_info())
1678         this->plt_->add_eh_frame(layout);
1679
1680       layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
1681                                       (elfcpp::SHF_ALLOC
1682                                        | elfcpp::SHF_EXECINSTR),
1683                                       this->plt_, ORDER_PLT, false);
1684
1685       // Make the sh_info field of .rela.plt point to .plt.
1686       Output_section* rela_plt_os = this->plt_->rela_plt()->output_section();
1687       rela_plt_os->set_info_section(this->plt_->output_section());
1688     }
1689 }
1690
1691 // Return the section for TLSDESC relocations.
1692
1693 template<int size>
1694 typename Target_x86_64<size>::Reloc_section*
1695 Target_x86_64<size>::rela_tlsdesc_section(Layout* layout) const
1696 {
1697   return this->plt_section()->rela_tlsdesc(layout);
1698 }
1699
1700 // Create a PLT entry for a global symbol.
1701
1702 template<int size>
1703 void
1704 Target_x86_64<size>::make_plt_entry(Symbol_table* symtab, Layout* layout,
1705                                     Symbol* gsym)
1706 {
1707   if (gsym->has_plt_offset())
1708     return;
1709
1710   if (this->plt_ == NULL)
1711     this->make_plt_section(symtab, layout);
1712
1713   this->plt_->add_entry(symtab, layout, gsym);
1714 }
1715
1716 // Make a PLT entry for a local STT_GNU_IFUNC symbol.
1717
1718 template<int size>
1719 void
1720 Target_x86_64<size>::make_local_ifunc_plt_entry(
1721     Symbol_table* symtab, Layout* layout,
1722     Sized_relobj_file<size, false>* relobj,
1723     unsigned int local_sym_index)
1724 {
1725   if (relobj->local_has_plt_offset(local_sym_index))
1726     return;
1727   if (this->plt_ == NULL)
1728     this->make_plt_section(symtab, layout);
1729   unsigned int plt_offset = this->plt_->add_local_ifunc_entry(symtab, layout,
1730                                                               relobj,
1731                                                               local_sym_index);
1732   relobj->set_local_plt_offset(local_sym_index, plt_offset);
1733 }
1734
1735 // Return the number of entries in the PLT.
1736
1737 template<int size>
1738 unsigned int
1739 Target_x86_64<size>::plt_entry_count() const
1740 {
1741   if (this->plt_ == NULL)
1742     return 0;
1743   return this->plt_->entry_count();
1744 }
1745
1746 // Return the offset of the first non-reserved PLT entry.
1747
1748 template<int size>
1749 unsigned int
1750 Target_x86_64<size>::first_plt_entry_offset() const
1751 {
1752   return this->plt_->first_plt_entry_offset();
1753 }
1754
1755 // Return the size of each PLT entry.
1756
1757 template<int size>
1758 unsigned int
1759 Target_x86_64<size>::plt_entry_size() const
1760 {
1761   return this->plt_->get_plt_entry_size();
1762 }
1763
1764 // Create the GOT and PLT sections for an incremental update.
1765
1766 template<int size>
1767 Output_data_got_base*
1768 Target_x86_64<size>::init_got_plt_for_update(Symbol_table* symtab,
1769                                        Layout* layout,
1770                                        unsigned int got_count,
1771                                        unsigned int plt_count)
1772 {
1773   gold_assert(this->got_ == NULL);
1774
1775   this->got_ = new Output_data_got<64, false>(got_count * 8);
1776   layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
1777                                   (elfcpp::SHF_ALLOC
1778                                    | elfcpp::SHF_WRITE),
1779                                   this->got_, ORDER_RELRO_LAST,
1780                                   true);
1781
1782   // Add the three reserved entries.
1783   this->got_plt_ = new Output_data_space((plt_count + 3) * 8, 8, "** GOT PLT");
1784   layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
1785                                   (elfcpp::SHF_ALLOC
1786                                    | elfcpp::SHF_WRITE),
1787                                   this->got_plt_, ORDER_NON_RELRO_FIRST,
1788                                   false);
1789
1790   // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
1791   this->global_offset_table_ =
1792     symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
1793                                   Symbol_table::PREDEFINED,
1794                                   this->got_plt_,
1795                                   0, 0, elfcpp::STT_OBJECT,
1796                                   elfcpp::STB_LOCAL,
1797                                   elfcpp::STV_HIDDEN, 0,
1798                                   false, false);
1799
1800   // If there are any TLSDESC relocations, they get GOT entries in
1801   // .got.plt after the jump slot entries.
1802   // FIXME: Get the count for TLSDESC entries.
1803   this->got_tlsdesc_ = new Output_data_got<64, false>(0);
1804   layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
1805                                   elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE,
1806                                   this->got_tlsdesc_,
1807                                   ORDER_NON_RELRO_FIRST, false);
1808
1809   // If there are any IRELATIVE relocations, they get GOT entries in
1810   // .got.plt after the jump slot and TLSDESC entries.
1811   this->got_irelative_ = new Output_data_space(0, 8, "** GOT IRELATIVE PLT");
1812   layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
1813                                   elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE,
1814                                   this->got_irelative_,
1815                                   ORDER_NON_RELRO_FIRST, false);
1816
1817   // Create the PLT section.
1818   this->plt_ = this->make_data_plt(layout, this->got_,
1819                                    this->got_plt_,
1820                                    this->got_irelative_,
1821                                    plt_count);
1822
1823   // Add unwind information if requested.
1824   if (parameters->options().ld_generated_unwind_info())
1825     this->plt_->add_eh_frame(layout);
1826
1827   layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
1828                                   elfcpp::SHF_ALLOC | elfcpp::SHF_EXECINSTR,
1829                                   this->plt_, ORDER_PLT, false);
1830
1831   // Make the sh_info field of .rela.plt point to .plt.
1832   Output_section* rela_plt_os = this->plt_->rela_plt()->output_section();
1833   rela_plt_os->set_info_section(this->plt_->output_section());
1834
1835   // Create the rela_dyn section.
1836   this->rela_dyn_section(layout);
1837
1838   return this->got_;
1839 }
1840
1841 // Reserve a GOT entry for a local symbol, and regenerate any
1842 // necessary dynamic relocations.
1843
1844 template<int size>
1845 void
1846 Target_x86_64<size>::reserve_local_got_entry(
1847     unsigned int got_index,
1848     Sized_relobj<size, false>* obj,
1849     unsigned int r_sym,
1850     unsigned int got_type)
1851 {
1852   unsigned int got_offset = got_index * 8;
1853   Reloc_section* rela_dyn = this->rela_dyn_section(NULL);
1854
1855   this->got_->reserve_local(got_index, obj, r_sym, got_type);
1856   switch (got_type)
1857     {
1858     case GOT_TYPE_STANDARD:
1859       if (parameters->options().output_is_position_independent())
1860         rela_dyn->add_local_relative(obj, r_sym, elfcpp::R_X86_64_RELATIVE,
1861                                      this->got_, got_offset, 0, false);
1862       break;
1863     case GOT_TYPE_TLS_OFFSET:
1864       rela_dyn->add_local(obj, r_sym, elfcpp::R_X86_64_TPOFF64,
1865                           this->got_, got_offset, 0);
1866       break;
1867     case GOT_TYPE_TLS_PAIR:
1868       this->got_->reserve_slot(got_index + 1);
1869       rela_dyn->add_local(obj, r_sym, elfcpp::R_X86_64_DTPMOD64,
1870                           this->got_, got_offset, 0);
1871       break;
1872     case GOT_TYPE_TLS_DESC:
1873       gold_fatal(_("TLS_DESC not yet supported for incremental linking"));
1874       // this->got_->reserve_slot(got_index + 1);
1875       // rela_dyn->add_target_specific(elfcpp::R_X86_64_TLSDESC, arg,
1876       //                               this->got_, got_offset, 0);
1877       break;
1878     default:
1879       gold_unreachable();
1880     }
1881 }
1882
1883 // Reserve a GOT entry for a global symbol, and regenerate any
1884 // necessary dynamic relocations.
1885
1886 template<int size>
1887 void
1888 Target_x86_64<size>::reserve_global_got_entry(unsigned int got_index,
1889                                               Symbol* gsym,
1890                                               unsigned int got_type)
1891 {
1892   unsigned int got_offset = got_index * 8;
1893   Reloc_section* rela_dyn = this->rela_dyn_section(NULL);
1894
1895   this->got_->reserve_global(got_index, gsym, got_type);
1896   switch (got_type)
1897     {
1898     case GOT_TYPE_STANDARD:
1899       if (!gsym->final_value_is_known())
1900         {
1901           if (gsym->is_from_dynobj()
1902               || gsym->is_undefined()
1903               || gsym->is_preemptible()
1904               || gsym->type() == elfcpp::STT_GNU_IFUNC)
1905             rela_dyn->add_global(gsym, elfcpp::R_X86_64_GLOB_DAT,
1906                                  this->got_, got_offset, 0);
1907           else
1908             rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_RELATIVE,
1909                                           this->got_, got_offset, 0, false);
1910         }
1911       break;
1912     case GOT_TYPE_TLS_OFFSET:
1913       rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_TPOFF64,
1914                                     this->got_, got_offset, 0, false);
1915       break;
1916     case GOT_TYPE_TLS_PAIR:
1917       this->got_->reserve_slot(got_index + 1);
1918       rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_DTPMOD64,
1919                                     this->got_, got_offset, 0, false);
1920       rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_DTPOFF64,
1921                                     this->got_, got_offset + 8, 0, false);
1922       break;
1923     case GOT_TYPE_TLS_DESC:
1924       this->got_->reserve_slot(got_index + 1);
1925       rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_TLSDESC,
1926                                     this->got_, got_offset, 0, false);
1927       break;
1928     default:
1929       gold_unreachable();
1930     }
1931 }
1932
1933 // Register an existing PLT entry for a global symbol.
1934
1935 template<int size>
1936 void
1937 Target_x86_64<size>::register_global_plt_entry(Symbol_table* symtab,
1938                                                Layout* layout,
1939                                                unsigned int plt_index,
1940                                                Symbol* gsym)
1941 {
1942   gold_assert(this->plt_ != NULL);
1943   gold_assert(!gsym->has_plt_offset());
1944
1945   this->plt_->reserve_slot(plt_index);
1946
1947   gsym->set_plt_offset((plt_index + 1) * this->plt_entry_size());
1948
1949   unsigned int got_offset = (plt_index + 3) * 8;
1950   this->plt_->add_relocation(symtab, layout, gsym, got_offset);
1951 }
1952
1953 // Force a COPY relocation for a given symbol.
1954
1955 template<int size>
1956 void
1957 Target_x86_64<size>::emit_copy_reloc(
1958     Symbol_table* symtab, Symbol* sym, Output_section* os, off_t offset)
1959 {
1960   this->copy_relocs_.emit_copy_reloc(symtab,
1961                                      symtab->get_sized_symbol<size>(sym),
1962                                      os,
1963                                      offset,
1964                                      this->rela_dyn_section(NULL));
1965 }
1966
1967 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
1968
1969 template<int size>
1970 void
1971 Target_x86_64<size>::define_tls_base_symbol(Symbol_table* symtab,
1972                                             Layout* layout)
1973 {
1974   if (this->tls_base_symbol_defined_)
1975     return;
1976
1977   Output_segment* tls_segment = layout->tls_segment();
1978   if (tls_segment != NULL)
1979     {
1980       bool is_exec = parameters->options().output_is_executable();
1981       symtab->define_in_output_segment("_TLS_MODULE_BASE_", NULL,
1982                                        Symbol_table::PREDEFINED,
1983                                        tls_segment, 0, 0,
1984                                        elfcpp::STT_TLS,
1985                                        elfcpp::STB_LOCAL,
1986                                        elfcpp::STV_HIDDEN, 0,
1987                                        (is_exec
1988                                         ? Symbol::SEGMENT_END
1989                                         : Symbol::SEGMENT_START),
1990                                        true);
1991     }
1992   this->tls_base_symbol_defined_ = true;
1993 }
1994
1995 // Create the reserved PLT and GOT entries for the TLS descriptor resolver.
1996
1997 template<int size>
1998 void
1999 Target_x86_64<size>::reserve_tlsdesc_entries(Symbol_table* symtab,
2000                                              Layout* layout)
2001 {
2002   if (this->plt_ == NULL)
2003     this->make_plt_section(symtab, layout);
2004
2005   if (!this->plt_->has_tlsdesc_entry())
2006     {
2007       // Allocate the TLSDESC_GOT entry.
2008       Output_data_got<64, false>* got = this->got_section(symtab, layout);
2009       unsigned int got_offset = got->add_constant(0);
2010
2011       // Allocate the TLSDESC_PLT entry.
2012       this->plt_->reserve_tlsdesc_entry(got_offset);
2013     }
2014 }
2015
2016 // Create a GOT entry for the TLS module index.
2017
2018 template<int size>
2019 unsigned int
2020 Target_x86_64<size>::got_mod_index_entry(Symbol_table* symtab, Layout* layout,
2021                                          Sized_relobj_file<size, false>* object)
2022 {
2023   if (this->got_mod_index_offset_ == -1U)
2024     {
2025       gold_assert(symtab != NULL && layout != NULL && object != NULL);
2026       Reloc_section* rela_dyn = this->rela_dyn_section(layout);
2027       Output_data_got<64, false>* got = this->got_section(symtab, layout);
2028       unsigned int got_offset = got->add_constant(0);
2029       rela_dyn->add_local(object, 0, elfcpp::R_X86_64_DTPMOD64, got,
2030                           got_offset, 0);
2031       got->add_constant(0);
2032       this->got_mod_index_offset_ = got_offset;
2033     }
2034   return this->got_mod_index_offset_;
2035 }
2036
2037 // Optimize the TLS relocation type based on what we know about the
2038 // symbol.  IS_FINAL is true if the final address of this symbol is
2039 // known at link time.
2040
2041 template<int size>
2042 tls::Tls_optimization
2043 Target_x86_64<size>::optimize_tls_reloc(bool is_final, int r_type)
2044 {
2045   // If we are generating a shared library, then we can't do anything
2046   // in the linker.
2047   if (parameters->options().shared())
2048     return tls::TLSOPT_NONE;
2049
2050   switch (r_type)
2051     {
2052     case elfcpp::R_X86_64_TLSGD:
2053     case elfcpp::R_X86_64_GOTPC32_TLSDESC:
2054     case elfcpp::R_X86_64_TLSDESC_CALL:
2055       // These are General-Dynamic which permits fully general TLS
2056       // access.  Since we know that we are generating an executable,
2057       // we can convert this to Initial-Exec.  If we also know that
2058       // this is a local symbol, we can further switch to Local-Exec.
2059       if (is_final)
2060         return tls::TLSOPT_TO_LE;
2061       return tls::TLSOPT_TO_IE;
2062
2063     case elfcpp::R_X86_64_TLSLD:
2064       // This is Local-Dynamic, which refers to a local symbol in the
2065       // dynamic TLS block.  Since we know that we generating an
2066       // executable, we can switch to Local-Exec.
2067       return tls::TLSOPT_TO_LE;
2068
2069     case elfcpp::R_X86_64_DTPOFF32:
2070     case elfcpp::R_X86_64_DTPOFF64:
2071       // Another Local-Dynamic reloc.
2072       return tls::TLSOPT_TO_LE;
2073
2074     case elfcpp::R_X86_64_GOTTPOFF:
2075       // These are Initial-Exec relocs which get the thread offset
2076       // from the GOT.  If we know that we are linking against the
2077       // local symbol, we can switch to Local-Exec, which links the
2078       // thread offset into the instruction.
2079       if (is_final)
2080         return tls::TLSOPT_TO_LE;
2081       return tls::TLSOPT_NONE;
2082
2083     case elfcpp::R_X86_64_TPOFF32:
2084       // When we already have Local-Exec, there is nothing further we
2085       // can do.
2086       return tls::TLSOPT_NONE;
2087
2088     default:
2089       gold_unreachable();
2090     }
2091 }
2092
2093 // Get the Reference_flags for a particular relocation.
2094
2095 template<int size>
2096 int
2097 Target_x86_64<size>::Scan::get_reference_flags(unsigned int r_type)
2098 {
2099   switch (r_type)
2100     {
2101     case elfcpp::R_X86_64_NONE:
2102     case elfcpp::R_X86_64_GNU_VTINHERIT:
2103     case elfcpp::R_X86_64_GNU_VTENTRY:
2104     case elfcpp::R_X86_64_GOTPC32:
2105     case elfcpp::R_X86_64_GOTPC64:
2106       // No symbol reference.
2107       return 0;
2108
2109     case elfcpp::R_X86_64_64:
2110     case elfcpp::R_X86_64_32:
2111     case elfcpp::R_X86_64_32S:
2112     case elfcpp::R_X86_64_16:
2113     case elfcpp::R_X86_64_8:
2114       return Symbol::ABSOLUTE_REF;
2115
2116     case elfcpp::R_X86_64_PC64:
2117     case elfcpp::R_X86_64_PC32:
2118     case elfcpp::R_X86_64_PC16:
2119     case elfcpp::R_X86_64_PC8:
2120     case elfcpp::R_X86_64_GOTOFF64:
2121       return Symbol::RELATIVE_REF;
2122
2123     case elfcpp::R_X86_64_PLT32:
2124     case elfcpp::R_X86_64_PLTOFF64:
2125       return Symbol::FUNCTION_CALL | Symbol::RELATIVE_REF;
2126
2127     case elfcpp::R_X86_64_GOT64:
2128     case elfcpp::R_X86_64_GOT32:
2129     case elfcpp::R_X86_64_GOTPCREL64:
2130     case elfcpp::R_X86_64_GOTPCREL:
2131     case elfcpp::R_X86_64_GOTPLT64:
2132       // Absolute in GOT.
2133       return Symbol::ABSOLUTE_REF;
2134
2135     case elfcpp::R_X86_64_TLSGD:            // Global-dynamic
2136     case elfcpp::R_X86_64_GOTPC32_TLSDESC:  // Global-dynamic (from ~oliva url)
2137     case elfcpp::R_X86_64_TLSDESC_CALL:
2138     case elfcpp::R_X86_64_TLSLD:            // Local-dynamic
2139     case elfcpp::R_X86_64_DTPOFF32:
2140     case elfcpp::R_X86_64_DTPOFF64:
2141     case elfcpp::R_X86_64_GOTTPOFF:         // Initial-exec
2142     case elfcpp::R_X86_64_TPOFF32:          // Local-exec
2143       return Symbol::TLS_REF;
2144
2145     case elfcpp::R_X86_64_COPY:
2146     case elfcpp::R_X86_64_GLOB_DAT:
2147     case elfcpp::R_X86_64_JUMP_SLOT:
2148     case elfcpp::R_X86_64_RELATIVE:
2149     case elfcpp::R_X86_64_IRELATIVE:
2150     case elfcpp::R_X86_64_TPOFF64:
2151     case elfcpp::R_X86_64_DTPMOD64:
2152     case elfcpp::R_X86_64_TLSDESC:
2153     case elfcpp::R_X86_64_SIZE32:
2154     case elfcpp::R_X86_64_SIZE64:
2155     default:
2156       // Not expected.  We will give an error later.
2157       return 0;
2158     }
2159 }
2160
2161 // Report an unsupported relocation against a local symbol.
2162
2163 template<int size>
2164 void
2165 Target_x86_64<size>::Scan::unsupported_reloc_local(
2166      Sized_relobj_file<size, false>* object,
2167      unsigned int r_type)
2168 {
2169   gold_error(_("%s: unsupported reloc %u against local symbol"),
2170              object->name().c_str(), r_type);
2171 }
2172
2173 // We are about to emit a dynamic relocation of type R_TYPE.  If the
2174 // dynamic linker does not support it, issue an error.  The GNU linker
2175 // only issues a non-PIC error for an allocated read-only section.
2176 // Here we know the section is allocated, but we don't know that it is
2177 // read-only.  But we check for all the relocation types which the
2178 // glibc dynamic linker supports, so it seems appropriate to issue an
2179 // error even if the section is not read-only.  If GSYM is not NULL,
2180 // it is the symbol the relocation is against; if it is NULL, the
2181 // relocation is against a local symbol.
2182
2183 template<int size>
2184 void
2185 Target_x86_64<size>::Scan::check_non_pic(Relobj* object, unsigned int r_type,
2186                                          Symbol* gsym)
2187 {
2188   switch (r_type)
2189     {
2190       // These are the relocation types supported by glibc for x86_64
2191       // which should always work.
2192     case elfcpp::R_X86_64_RELATIVE:
2193     case elfcpp::R_X86_64_IRELATIVE:
2194     case elfcpp::R_X86_64_GLOB_DAT:
2195     case elfcpp::R_X86_64_JUMP_SLOT:
2196     case elfcpp::R_X86_64_DTPMOD64:
2197     case elfcpp::R_X86_64_DTPOFF64:
2198     case elfcpp::R_X86_64_TPOFF64:
2199     case elfcpp::R_X86_64_64:
2200     case elfcpp::R_X86_64_COPY:
2201       return;
2202
2203       // glibc supports these reloc types, but they can overflow.
2204     case elfcpp::R_X86_64_PC32:
2205       // A PC relative reference is OK against a local symbol or if
2206       // the symbol is defined locally.
2207       if (gsym == NULL
2208           || (!gsym->is_from_dynobj()
2209               && !gsym->is_undefined()
2210               && !gsym->is_preemptible()))
2211         return;
2212       /* Fall through.  */
2213     case elfcpp::R_X86_64_32:
2214       // R_X86_64_32 is OK for x32.
2215       if (size == 32 && r_type == elfcpp::R_X86_64_32)
2216         return;
2217       if (this->issued_non_pic_error_)
2218         return;
2219       gold_assert(parameters->options().output_is_position_independent());
2220       if (gsym == NULL)
2221         object->error(_("requires dynamic R_X86_64_32 reloc which may "
2222                         "overflow at runtime; recompile with -fPIC"));
2223       else
2224         object->error(_("requires dynamic %s reloc against '%s' which may "
2225                         "overflow at runtime; recompile with -fPIC"),
2226                       (r_type == elfcpp::R_X86_64_32
2227                        ? "R_X86_64_32"
2228                        : "R_X86_64_PC32"),
2229                       gsym->name());
2230       this->issued_non_pic_error_ = true;
2231       return;
2232
2233     default:
2234       // This prevents us from issuing more than one error per reloc
2235       // section.  But we can still wind up issuing more than one
2236       // error per object file.
2237       if (this->issued_non_pic_error_)
2238         return;
2239       gold_assert(parameters->options().output_is_position_independent());
2240       object->error(_("requires unsupported dynamic reloc %u; "
2241                       "recompile with -fPIC"),
2242                     r_type);
2243       this->issued_non_pic_error_ = true;
2244       return;
2245
2246     case elfcpp::R_X86_64_NONE:
2247       gold_unreachable();
2248     }
2249 }
2250
2251 // Return whether we need to make a PLT entry for a relocation of the
2252 // given type against a STT_GNU_IFUNC symbol.
2253
2254 template<int size>
2255 bool
2256 Target_x86_64<size>::Scan::reloc_needs_plt_for_ifunc(
2257      Sized_relobj_file<size, false>* object,
2258      unsigned int r_type)
2259 {
2260   int flags = Scan::get_reference_flags(r_type);
2261   if (flags & Symbol::TLS_REF)
2262     gold_error(_("%s: unsupported TLS reloc %u for IFUNC symbol"),
2263                object->name().c_str(), r_type);
2264   return flags != 0;
2265 }
2266
2267 // Scan a relocation for a local symbol.
2268
2269 template<int size>
2270 inline void
2271 Target_x86_64<size>::Scan::local(Symbol_table* symtab,
2272                                  Layout* layout,
2273                                  Target_x86_64<size>* target,
2274                                  Sized_relobj_file<size, false>* object,
2275                                  unsigned int data_shndx,
2276                                  Output_section* output_section,
2277                                  const elfcpp::Rela<size, false>& reloc,
2278                                  unsigned int r_type,
2279                                  const elfcpp::Sym<size, false>& lsym,
2280                                  bool is_discarded)
2281 {
2282   if (is_discarded)
2283     return;
2284
2285   // A local STT_GNU_IFUNC symbol may require a PLT entry.
2286   bool is_ifunc = lsym.get_st_type() == elfcpp::STT_GNU_IFUNC;
2287   if (is_ifunc && this->reloc_needs_plt_for_ifunc(object, r_type))
2288     {
2289       unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2290       target->make_local_ifunc_plt_entry(symtab, layout, object, r_sym);
2291     }
2292
2293   switch (r_type)
2294     {
2295     case elfcpp::R_X86_64_NONE:
2296     case elfcpp::R_X86_64_GNU_VTINHERIT:
2297     case elfcpp::R_X86_64_GNU_VTENTRY:
2298       break;
2299
2300     case elfcpp::R_X86_64_64:
2301       // If building a shared library (or a position-independent
2302       // executable), we need to create a dynamic relocation for this
2303       // location.  The relocation applied at link time will apply the
2304       // link-time value, so we flag the location with an
2305       // R_X86_64_RELATIVE relocation so the dynamic loader can
2306       // relocate it easily.
2307       if (parameters->options().output_is_position_independent())
2308         {
2309           unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2310           Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2311           rela_dyn->add_local_relative(object, r_sym,
2312                                        (size == 32
2313                                         ? elfcpp::R_X86_64_RELATIVE64
2314                                         : elfcpp::R_X86_64_RELATIVE),
2315                                        output_section, data_shndx,
2316                                        reloc.get_r_offset(),
2317                                        reloc.get_r_addend(), is_ifunc);
2318         }
2319       break;
2320
2321     case elfcpp::R_X86_64_32:
2322     case elfcpp::R_X86_64_32S:
2323     case elfcpp::R_X86_64_16:
2324     case elfcpp::R_X86_64_8:
2325       // If building a shared library (or a position-independent
2326       // executable), we need to create a dynamic relocation for this
2327       // location.  We can't use an R_X86_64_RELATIVE relocation
2328       // because that is always a 64-bit relocation.
2329       if (parameters->options().output_is_position_independent())
2330         {
2331           // Use R_X86_64_RELATIVE relocation for R_X86_64_32 under x32.
2332           if (size == 32 && r_type == elfcpp::R_X86_64_32)
2333             {
2334               unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2335               Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2336               rela_dyn->add_local_relative(object, r_sym,
2337                                            elfcpp::R_X86_64_RELATIVE,
2338                                            output_section, data_shndx,
2339                                            reloc.get_r_offset(),
2340                                            reloc.get_r_addend(), is_ifunc);
2341               break;
2342             }
2343
2344           this->check_non_pic(object, r_type, NULL);
2345
2346           Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2347           unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2348           if (lsym.get_st_type() != elfcpp::STT_SECTION)
2349             rela_dyn->add_local(object, r_sym, r_type, output_section,
2350                                 data_shndx, reloc.get_r_offset(),
2351                                 reloc.get_r_addend());
2352           else
2353             {
2354               gold_assert(lsym.get_st_value() == 0);
2355               unsigned int shndx = lsym.get_st_shndx();
2356               bool is_ordinary;
2357               shndx = object->adjust_sym_shndx(r_sym, shndx,
2358                                                &is_ordinary);
2359               if (!is_ordinary)
2360                 object->error(_("section symbol %u has bad shndx %u"),
2361                               r_sym, shndx);
2362               else
2363                 rela_dyn->add_local_section(object, shndx,
2364                                             r_type, output_section,
2365                                             data_shndx, reloc.get_r_offset(),
2366                                             reloc.get_r_addend());
2367             }
2368         }
2369       break;
2370
2371     case elfcpp::R_X86_64_PC64:
2372     case elfcpp::R_X86_64_PC32:
2373     case elfcpp::R_X86_64_PC16:
2374     case elfcpp::R_X86_64_PC8:
2375       break;
2376
2377     case elfcpp::R_X86_64_PLT32:
2378       // Since we know this is a local symbol, we can handle this as a
2379       // PC32 reloc.
2380       break;
2381
2382     case elfcpp::R_X86_64_GOTPC32:
2383     case elfcpp::R_X86_64_GOTOFF64:
2384     case elfcpp::R_X86_64_GOTPC64:
2385     case elfcpp::R_X86_64_PLTOFF64:
2386       // We need a GOT section.
2387       target->got_section(symtab, layout);
2388       // For PLTOFF64, we'd normally want a PLT section, but since we
2389       // know this is a local symbol, no PLT is needed.
2390       break;
2391
2392     case elfcpp::R_X86_64_GOT64:
2393     case elfcpp::R_X86_64_GOT32:
2394     case elfcpp::R_X86_64_GOTPCREL64:
2395     case elfcpp::R_X86_64_GOTPCREL:
2396     case elfcpp::R_X86_64_GOTPLT64:
2397       {
2398         // The symbol requires a GOT entry.
2399         Output_data_got<64, false>* got = target->got_section(symtab, layout);
2400         unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2401
2402         // For a STT_GNU_IFUNC symbol we want the PLT offset.  That
2403         // lets function pointers compare correctly with shared
2404         // libraries.  Otherwise we would need an IRELATIVE reloc.
2405         bool is_new;
2406         if (is_ifunc)
2407           is_new = got->add_local_plt(object, r_sym, GOT_TYPE_STANDARD);
2408         else
2409           is_new = got->add_local(object, r_sym, GOT_TYPE_STANDARD);
2410         if (is_new)
2411           {
2412             // If we are generating a shared object, we need to add a
2413             // dynamic relocation for this symbol's GOT entry.
2414             if (parameters->options().output_is_position_independent())
2415               {
2416                 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2417                 // R_X86_64_RELATIVE assumes a 64-bit relocation.
2418                 if (r_type != elfcpp::R_X86_64_GOT32)
2419                   {
2420                     unsigned int got_offset =
2421                       object->local_got_offset(r_sym, GOT_TYPE_STANDARD);
2422                     rela_dyn->add_local_relative(object, r_sym,
2423                                                  elfcpp::R_X86_64_RELATIVE,
2424                                                  got, got_offset, 0, is_ifunc);
2425                   }
2426                 else
2427                   {
2428                     this->check_non_pic(object, r_type, NULL);
2429
2430                     gold_assert(lsym.get_st_type() != elfcpp::STT_SECTION);
2431                     rela_dyn->add_local(
2432                         object, r_sym, r_type, got,
2433                         object->local_got_offset(r_sym, GOT_TYPE_STANDARD), 0);
2434                   }
2435               }
2436           }
2437         // For GOTPLT64, we'd normally want a PLT section, but since
2438         // we know this is a local symbol, no PLT is needed.
2439       }
2440       break;
2441
2442     case elfcpp::R_X86_64_COPY:
2443     case elfcpp::R_X86_64_GLOB_DAT:
2444     case elfcpp::R_X86_64_JUMP_SLOT:
2445     case elfcpp::R_X86_64_RELATIVE:
2446     case elfcpp::R_X86_64_IRELATIVE:
2447       // These are outstanding tls relocs, which are unexpected when linking
2448     case elfcpp::R_X86_64_TPOFF64:
2449     case elfcpp::R_X86_64_DTPMOD64:
2450     case elfcpp::R_X86_64_TLSDESC:
2451       gold_error(_("%s: unexpected reloc %u in object file"),
2452                  object->name().c_str(), r_type);
2453       break;
2454
2455       // These are initial tls relocs, which are expected when linking
2456     case elfcpp::R_X86_64_TLSGD:            // Global-dynamic
2457     case elfcpp::R_X86_64_GOTPC32_TLSDESC:  // Global-dynamic (from ~oliva url)
2458     case elfcpp::R_X86_64_TLSDESC_CALL:
2459     case elfcpp::R_X86_64_TLSLD:            // Local-dynamic
2460     case elfcpp::R_X86_64_DTPOFF32:
2461     case elfcpp::R_X86_64_DTPOFF64:
2462     case elfcpp::R_X86_64_GOTTPOFF:         // Initial-exec
2463     case elfcpp::R_X86_64_TPOFF32:          // Local-exec
2464       {
2465         bool output_is_shared = parameters->options().shared();
2466         const tls::Tls_optimization optimized_type
2467             = Target_x86_64<size>::optimize_tls_reloc(!output_is_shared,
2468                                                       r_type);
2469         switch (r_type)
2470           {
2471           case elfcpp::R_X86_64_TLSGD:       // General-dynamic
2472             if (optimized_type == tls::TLSOPT_NONE)
2473               {
2474                 // Create a pair of GOT entries for the module index and
2475                 // dtv-relative offset.
2476                 Output_data_got<64, false>* got
2477                     = target->got_section(symtab, layout);
2478                 unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2479                 unsigned int shndx = lsym.get_st_shndx();
2480                 bool is_ordinary;
2481                 shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
2482                 if (!is_ordinary)
2483                   object->error(_("local symbol %u has bad shndx %u"),
2484                               r_sym, shndx);
2485                 else
2486                   got->add_local_pair_with_rel(object, r_sym,
2487                                                shndx,
2488                                                GOT_TYPE_TLS_PAIR,
2489                                                target->rela_dyn_section(layout),
2490                                                elfcpp::R_X86_64_DTPMOD64);
2491               }
2492             else if (optimized_type != tls::TLSOPT_TO_LE)
2493               unsupported_reloc_local(object, r_type);
2494             break;
2495
2496           case elfcpp::R_X86_64_GOTPC32_TLSDESC:
2497             target->define_tls_base_symbol(symtab, layout);
2498             if (optimized_type == tls::TLSOPT_NONE)
2499               {
2500                 // Create reserved PLT and GOT entries for the resolver.
2501                 target->reserve_tlsdesc_entries(symtab, layout);
2502
2503                 // Generate a double GOT entry with an
2504                 // R_X86_64_TLSDESC reloc.  The R_X86_64_TLSDESC reloc
2505                 // is resolved lazily, so the GOT entry needs to be in
2506                 // an area in .got.plt, not .got.  Call got_section to
2507                 // make sure the section has been created.
2508                 target->got_section(symtab, layout);
2509                 Output_data_got<64, false>* got = target->got_tlsdesc_section();
2510                 unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2511                 if (!object->local_has_got_offset(r_sym, GOT_TYPE_TLS_DESC))
2512                   {
2513                     unsigned int got_offset = got->add_constant(0);
2514                     got->add_constant(0);
2515                     object->set_local_got_offset(r_sym, GOT_TYPE_TLS_DESC,
2516                                                  got_offset);
2517                     Reloc_section* rt = target->rela_tlsdesc_section(layout);
2518                     // We store the arguments we need in a vector, and
2519                     // use the index into the vector as the parameter
2520                     // to pass to the target specific routines.
2521                     uintptr_t intarg = target->add_tlsdesc_info(object, r_sym);
2522                     void* arg = reinterpret_cast<void*>(intarg);
2523                     rt->add_target_specific(elfcpp::R_X86_64_TLSDESC, arg,
2524                                             got, got_offset, 0);
2525                   }
2526               }
2527             else if (optimized_type != tls::TLSOPT_TO_LE)
2528               unsupported_reloc_local(object, r_type);
2529             break;
2530
2531           case elfcpp::R_X86_64_TLSDESC_CALL:
2532             break;
2533
2534           case elfcpp::R_X86_64_TLSLD:       // Local-dynamic
2535             if (optimized_type == tls::TLSOPT_NONE)
2536               {
2537                 // Create a GOT entry for the module index.
2538                 target->got_mod_index_entry(symtab, layout, object);
2539               }
2540             else if (optimized_type != tls::TLSOPT_TO_LE)
2541               unsupported_reloc_local(object, r_type);
2542             break;
2543
2544           case elfcpp::R_X86_64_DTPOFF32:
2545           case elfcpp::R_X86_64_DTPOFF64:
2546             break;
2547
2548           case elfcpp::R_X86_64_GOTTPOFF:    // Initial-exec
2549             layout->set_has_static_tls();
2550             if (optimized_type == tls::TLSOPT_NONE)
2551               {
2552                 // Create a GOT entry for the tp-relative offset.
2553                 Output_data_got<64, false>* got
2554                     = target->got_section(symtab, layout);
2555                 unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2556                 got->add_local_with_rel(object, r_sym, GOT_TYPE_TLS_OFFSET,
2557                                         target->rela_dyn_section(layout),
2558                                         elfcpp::R_X86_64_TPOFF64);
2559               }
2560             else if (optimized_type != tls::TLSOPT_TO_LE)
2561               unsupported_reloc_local(object, r_type);
2562             break;
2563
2564           case elfcpp::R_X86_64_TPOFF32:     // Local-exec
2565             layout->set_has_static_tls();
2566             if (output_is_shared)
2567               unsupported_reloc_local(object, r_type);
2568             break;
2569
2570           default:
2571             gold_unreachable();
2572           }
2573       }
2574       break;
2575
2576     case elfcpp::R_X86_64_SIZE32:
2577     case elfcpp::R_X86_64_SIZE64:
2578     default:
2579       gold_error(_("%s: unsupported reloc %u against local symbol"),
2580                  object->name().c_str(), r_type);
2581       break;
2582     }
2583 }
2584
2585
2586 // Report an unsupported relocation against a global symbol.
2587
2588 template<int size>
2589 void
2590 Target_x86_64<size>::Scan::unsupported_reloc_global(
2591     Sized_relobj_file<size, false>* object,
2592     unsigned int r_type,
2593     Symbol* gsym)
2594 {
2595   gold_error(_("%s: unsupported reloc %u against global symbol %s"),
2596              object->name().c_str(), r_type, gsym->demangled_name().c_str());
2597 }
2598
2599 // Returns true if this relocation type could be that of a function pointer.
2600 template<int size>
2601 inline bool
2602 Target_x86_64<size>::Scan::possible_function_pointer_reloc(unsigned int r_type)
2603 {
2604   switch (r_type)
2605     {
2606     case elfcpp::R_X86_64_64:
2607     case elfcpp::R_X86_64_32:
2608     case elfcpp::R_X86_64_32S:
2609     case elfcpp::R_X86_64_16:
2610     case elfcpp::R_X86_64_8:
2611     case elfcpp::R_X86_64_GOT64:
2612     case elfcpp::R_X86_64_GOT32:
2613     case elfcpp::R_X86_64_GOTPCREL64:
2614     case elfcpp::R_X86_64_GOTPCREL:
2615     case elfcpp::R_X86_64_GOTPLT64:
2616       {
2617         return true;
2618       }
2619     }
2620   return false;
2621 }
2622
2623 // For safe ICF, scan a relocation for a local symbol to check if it
2624 // corresponds to a function pointer being taken.  In that case mark
2625 // the function whose pointer was taken as not foldable.
2626
2627 template<int size>
2628 inline bool
2629 Target_x86_64<size>::Scan::local_reloc_may_be_function_pointer(
2630   Symbol_table* ,
2631   Layout* ,
2632   Target_x86_64<size>* ,
2633   Sized_relobj_file<size, false>* ,
2634   unsigned int ,
2635   Output_section* ,
2636   const elfcpp::Rela<size, false>& ,
2637   unsigned int r_type,
2638   const elfcpp::Sym<size, false>&)
2639 {
2640   // When building a shared library, do not fold any local symbols as it is
2641   // not possible to distinguish pointer taken versus a call by looking at
2642   // the relocation types.
2643   return (parameters->options().shared()
2644           || possible_function_pointer_reloc(r_type));
2645 }
2646
2647 // For safe ICF, scan a relocation for a global symbol to check if it
2648 // corresponds to a function pointer being taken.  In that case mark
2649 // the function whose pointer was taken as not foldable.
2650
2651 template<int size>
2652 inline bool
2653 Target_x86_64<size>::Scan::global_reloc_may_be_function_pointer(
2654   Symbol_table*,
2655   Layout* ,
2656   Target_x86_64<size>* ,
2657   Sized_relobj_file<size, false>* ,
2658   unsigned int ,
2659   Output_section* ,
2660   const elfcpp::Rela<size, false>& ,
2661   unsigned int r_type,
2662   Symbol* gsym)
2663 {
2664   // When building a shared library, do not fold symbols whose visibility
2665   // is hidden, internal or protected.
2666   return ((parameters->options().shared()
2667            && (gsym->visibility() == elfcpp::STV_INTERNAL
2668                || gsym->visibility() == elfcpp::STV_PROTECTED
2669                || gsym->visibility() == elfcpp::STV_HIDDEN))
2670           || possible_function_pointer_reloc(r_type));
2671 }
2672
2673 // Scan a relocation for a global symbol.
2674
2675 template<int size>
2676 inline void
2677 Target_x86_64<size>::Scan::global(Symbol_table* symtab,
2678                             Layout* layout,
2679                             Target_x86_64<size>* target,
2680                             Sized_relobj_file<size, false>* object,
2681                             unsigned int data_shndx,
2682                             Output_section* output_section,
2683                             const elfcpp::Rela<size, false>& reloc,
2684                             unsigned int r_type,
2685                             Symbol* gsym)
2686 {
2687   // A STT_GNU_IFUNC symbol may require a PLT entry.
2688   if (gsym->type() == elfcpp::STT_GNU_IFUNC
2689       && this->reloc_needs_plt_for_ifunc(object, r_type))
2690     target->make_plt_entry(symtab, layout, gsym);
2691
2692   switch (r_type)
2693     {
2694     case elfcpp::R_X86_64_NONE:
2695     case elfcpp::R_X86_64_GNU_VTINHERIT:
2696     case elfcpp::R_X86_64_GNU_VTENTRY:
2697       break;
2698
2699     case elfcpp::R_X86_64_64:
2700     case elfcpp::R_X86_64_32:
2701     case elfcpp::R_X86_64_32S:
2702     case elfcpp::R_X86_64_16:
2703     case elfcpp::R_X86_64_8:
2704       {
2705         // Make a PLT entry if necessary.
2706         if (gsym->needs_plt_entry())
2707           {
2708             target->make_plt_entry(symtab, layout, gsym);
2709             // Since this is not a PC-relative relocation, we may be
2710             // taking the address of a function. In that case we need to
2711             // set the entry in the dynamic symbol table to the address of
2712             // the PLT entry.
2713             if (gsym->is_from_dynobj() && !parameters->options().shared())
2714               gsym->set_needs_dynsym_value();
2715           }
2716         // Make a dynamic relocation if necessary.
2717         if (gsym->needs_dynamic_reloc(Scan::get_reference_flags(r_type)))
2718           {
2719             if (gsym->may_need_copy_reloc())
2720               {
2721                 target->copy_reloc(symtab, layout, object,
2722                                    data_shndx, output_section, gsym, reloc);
2723               }
2724             else if (((size == 64 && r_type == elfcpp::R_X86_64_64)
2725                       || (size == 32 && r_type == elfcpp::R_X86_64_32))
2726                      && gsym->type() == elfcpp::STT_GNU_IFUNC
2727                      && gsym->can_use_relative_reloc(false)
2728                      && !gsym->is_from_dynobj()
2729                      && !gsym->is_undefined()
2730                      && !gsym->is_preemptible())
2731               {
2732                 // Use an IRELATIVE reloc for a locally defined
2733                 // STT_GNU_IFUNC symbol.  This makes a function
2734                 // address in a PIE executable match the address in a
2735                 // shared library that it links against.
2736                 Reloc_section* rela_dyn =
2737                   target->rela_irelative_section(layout);
2738                 unsigned int r_type = elfcpp::R_X86_64_IRELATIVE;
2739                 rela_dyn->add_symbolless_global_addend(gsym, r_type,
2740                                                        output_section, object,
2741                                                        data_shndx,
2742                                                        reloc.get_r_offset(),
2743                                                        reloc.get_r_addend());
2744               }
2745             else if (((size == 64 && r_type == elfcpp::R_X86_64_64)
2746                       || (size == 32 && r_type == elfcpp::R_X86_64_32))
2747                      && gsym->can_use_relative_reloc(false))
2748               {
2749                 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2750                 rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_RELATIVE,
2751                                               output_section, object,
2752                                               data_shndx,
2753                                               reloc.get_r_offset(),
2754                                               reloc.get_r_addend(), false);
2755               }
2756             else
2757               {
2758                 this->check_non_pic(object, r_type, gsym);
2759                 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2760                 rela_dyn->add_global(gsym, r_type, output_section, object,
2761                                      data_shndx, reloc.get_r_offset(),
2762                                      reloc.get_r_addend());
2763               }
2764           }
2765       }
2766       break;
2767
2768     case elfcpp::R_X86_64_PC64:
2769     case elfcpp::R_X86_64_PC32:
2770     case elfcpp::R_X86_64_PC16:
2771     case elfcpp::R_X86_64_PC8:
2772       {
2773         // Make a PLT entry if necessary.
2774         if (gsym->needs_plt_entry())
2775           target->make_plt_entry(symtab, layout, gsym);
2776         // Make a dynamic relocation if necessary.
2777         if (gsym->needs_dynamic_reloc(Scan::get_reference_flags(r_type)))
2778           {
2779             if (gsym->may_need_copy_reloc())
2780               {
2781                 target->copy_reloc(symtab, layout, object,
2782                                    data_shndx, output_section, gsym, reloc);
2783               }
2784             else
2785               {
2786                 this->check_non_pic(object, r_type, gsym);
2787                 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2788                 rela_dyn->add_global(gsym, r_type, output_section, object,
2789                                      data_shndx, reloc.get_r_offset(),
2790                                      reloc.get_r_addend());
2791               }
2792           }
2793       }
2794       break;
2795
2796     case elfcpp::R_X86_64_GOT64:
2797     case elfcpp::R_X86_64_GOT32:
2798     case elfcpp::R_X86_64_GOTPCREL64:
2799     case elfcpp::R_X86_64_GOTPCREL:
2800     case elfcpp::R_X86_64_GOTPLT64:
2801       {
2802         // The symbol requires a GOT entry.
2803         Output_data_got<64, false>* got = target->got_section(symtab, layout);
2804         if (gsym->final_value_is_known())
2805           {
2806             // For a STT_GNU_IFUNC symbol we want the PLT address.
2807             if (gsym->type() == elfcpp::STT_GNU_IFUNC)
2808               got->add_global_plt(gsym, GOT_TYPE_STANDARD);
2809             else
2810               got->add_global(gsym, GOT_TYPE_STANDARD);
2811           }
2812         else
2813           {
2814             // If this symbol is not fully resolved, we need to add a
2815             // dynamic relocation for it.
2816             Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2817
2818             // Use a GLOB_DAT rather than a RELATIVE reloc if:
2819             //
2820             // 1) The symbol may be defined in some other module.
2821             //
2822             // 2) We are building a shared library and this is a
2823             // protected symbol; using GLOB_DAT means that the dynamic
2824             // linker can use the address of the PLT in the main
2825             // executable when appropriate so that function address
2826             // comparisons work.
2827             //
2828             // 3) This is a STT_GNU_IFUNC symbol in position dependent
2829             // code, again so that function address comparisons work.
2830             if (gsym->is_from_dynobj()
2831                 || gsym->is_undefined()
2832                 || gsym->is_preemptible()
2833                 || (gsym->visibility() == elfcpp::STV_PROTECTED
2834                     && parameters->options().shared())
2835                 || (gsym->type() == elfcpp::STT_GNU_IFUNC
2836                     && parameters->options().output_is_position_independent()))
2837               got->add_global_with_rel(gsym, GOT_TYPE_STANDARD, rela_dyn,
2838                                        elfcpp::R_X86_64_GLOB_DAT);
2839             else
2840               {
2841                 // For a STT_GNU_IFUNC symbol we want to write the PLT
2842                 // offset into the GOT, so that function pointer
2843                 // comparisons work correctly.
2844                 bool is_new;
2845                 if (gsym->type() != elfcpp::STT_GNU_IFUNC)
2846                   is_new = got->add_global(gsym, GOT_TYPE_STANDARD);
2847                 else
2848                   {
2849                     is_new = got->add_global_plt(gsym, GOT_TYPE_STANDARD);
2850                     // Tell the dynamic linker to use the PLT address
2851                     // when resolving relocations.
2852                     if (gsym->is_from_dynobj()
2853                         && !parameters->options().shared())
2854                       gsym->set_needs_dynsym_value();
2855                   }
2856                 if (is_new)
2857                   {
2858                     unsigned int got_off = gsym->got_offset(GOT_TYPE_STANDARD);
2859                     rela_dyn->add_global_relative(gsym,
2860                                                   elfcpp::R_X86_64_RELATIVE,
2861                                                   got, got_off, 0, false);
2862                   }
2863               }
2864           }
2865         // For GOTPLT64, we also need a PLT entry (but only if the
2866         // symbol is not fully resolved).
2867         if (r_type == elfcpp::R_X86_64_GOTPLT64
2868             && !gsym->final_value_is_known())
2869           target->make_plt_entry(symtab, layout, gsym);
2870       }
2871       break;
2872
2873     case elfcpp::R_X86_64_PLT32:
2874       // If the symbol is fully resolved, this is just a PC32 reloc.
2875       // Otherwise we need a PLT entry.
2876       if (gsym->final_value_is_known())
2877         break;
2878       // If building a shared library, we can also skip the PLT entry
2879       // if the symbol is defined in the output file and is protected
2880       // or hidden.
2881       if (gsym->is_defined()
2882           && !gsym->is_from_dynobj()
2883           && !gsym->is_preemptible())
2884         break;
2885       target->make_plt_entry(symtab, layout, gsym);
2886       break;
2887
2888     case elfcpp::R_X86_64_GOTPC32:
2889     case elfcpp::R_X86_64_GOTOFF64:
2890     case elfcpp::R_X86_64_GOTPC64:
2891     case elfcpp::R_X86_64_PLTOFF64:
2892       // We need a GOT section.
2893       target->got_section(symtab, layout);
2894       // For PLTOFF64, we also need a PLT entry (but only if the
2895       // symbol is not fully resolved).
2896       if (r_type == elfcpp::R_X86_64_PLTOFF64
2897           && !gsym->final_value_is_known())
2898         target->make_plt_entry(symtab, layout, gsym);
2899       break;
2900
2901     case elfcpp::R_X86_64_COPY:
2902     case elfcpp::R_X86_64_GLOB_DAT:
2903     case elfcpp::R_X86_64_JUMP_SLOT:
2904     case elfcpp::R_X86_64_RELATIVE:
2905     case elfcpp::R_X86_64_IRELATIVE:
2906       // These are outstanding tls relocs, which are unexpected when linking
2907     case elfcpp::R_X86_64_TPOFF64:
2908     case elfcpp::R_X86_64_DTPMOD64:
2909     case elfcpp::R_X86_64_TLSDESC:
2910       gold_error(_("%s: unexpected reloc %u in object file"),
2911                  object->name().c_str(), r_type);
2912       break;
2913
2914       // These are initial tls relocs, which are expected for global()
2915     case elfcpp::R_X86_64_TLSGD:            // Global-dynamic
2916     case elfcpp::R_X86_64_GOTPC32_TLSDESC:  // Global-dynamic (from ~oliva url)
2917     case elfcpp::R_X86_64_TLSDESC_CALL:
2918     case elfcpp::R_X86_64_TLSLD:            // Local-dynamic
2919     case elfcpp::R_X86_64_DTPOFF32:
2920     case elfcpp::R_X86_64_DTPOFF64:
2921     case elfcpp::R_X86_64_GOTTPOFF:         // Initial-exec
2922     case elfcpp::R_X86_64_TPOFF32:          // Local-exec
2923       {
2924         const bool is_final = gsym->final_value_is_known();
2925         const tls::Tls_optimization optimized_type
2926             = Target_x86_64<size>::optimize_tls_reloc(is_final, r_type);
2927         switch (r_type)
2928           {
2929           case elfcpp::R_X86_64_TLSGD:       // General-dynamic
2930             if (optimized_type == tls::TLSOPT_NONE)
2931               {
2932                 // Create a pair of GOT entries for the module index and
2933                 // dtv-relative offset.
2934                 Output_data_got<64, false>* got
2935                     = target->got_section(symtab, layout);
2936                 got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_PAIR,
2937                                               target->rela_dyn_section(layout),
2938                                               elfcpp::R_X86_64_DTPMOD64,
2939                                               elfcpp::R_X86_64_DTPOFF64);
2940               }
2941             else if (optimized_type == tls::TLSOPT_TO_IE)
2942               {
2943                 // Create a GOT entry for the tp-relative offset.
2944                 Output_data_got<64, false>* got
2945                     = target->got_section(symtab, layout);
2946                 got->add_global_with_rel(gsym, GOT_TYPE_TLS_OFFSET,
2947                                          target->rela_dyn_section(layout),
2948                                          elfcpp::R_X86_64_TPOFF64);
2949               }
2950             else if (optimized_type != tls::TLSOPT_TO_LE)
2951               unsupported_reloc_global(object, r_type, gsym);
2952             break;
2953
2954           case elfcpp::R_X86_64_GOTPC32_TLSDESC:
2955             target->define_tls_base_symbol(symtab, layout);
2956             if (optimized_type == tls::TLSOPT_NONE)
2957               {
2958                 // Create reserved PLT and GOT entries for the resolver.
2959                 target->reserve_tlsdesc_entries(symtab, layout);
2960
2961                 // Create a double GOT entry with an R_X86_64_TLSDESC
2962                 // reloc.  The R_X86_64_TLSDESC reloc is resolved
2963                 // lazily, so the GOT entry needs to be in an area in
2964                 // .got.plt, not .got.  Call got_section to make sure
2965                 // the section has been created.
2966                 target->got_section(symtab, layout);
2967                 Output_data_got<64, false>* got = target->got_tlsdesc_section();
2968                 Reloc_section* rt = target->rela_tlsdesc_section(layout);
2969                 got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_DESC, rt,
2970                                               elfcpp::R_X86_64_TLSDESC, 0);
2971               }
2972             else if (optimized_type == tls::TLSOPT_TO_IE)
2973               {
2974                 // Create a GOT entry for the tp-relative offset.
2975                 Output_data_got<64, false>* got
2976                     = target->got_section(symtab, layout);
2977                 got->add_global_with_rel(gsym, GOT_TYPE_TLS_OFFSET,
2978                                          target->rela_dyn_section(layout),
2979                                          elfcpp::R_X86_64_TPOFF64);
2980               }
2981             else if (optimized_type != tls::TLSOPT_TO_LE)
2982               unsupported_reloc_global(object, r_type, gsym);
2983             break;
2984
2985           case elfcpp::R_X86_64_TLSDESC_CALL:
2986             break;
2987
2988           case elfcpp::R_X86_64_TLSLD:       // Local-dynamic
2989             if (optimized_type == tls::TLSOPT_NONE)
2990               {
2991                 // Create a GOT entry for the module index.
2992                 target->got_mod_index_entry(symtab, layout, object);
2993               }
2994             else if (optimized_type != tls::TLSOPT_TO_LE)
2995               unsupported_reloc_global(object, r_type, gsym);
2996             break;
2997
2998           case elfcpp::R_X86_64_DTPOFF32:
2999           case elfcpp::R_X86_64_DTPOFF64:
3000             break;
3001
3002           case elfcpp::R_X86_64_GOTTPOFF:    // Initial-exec
3003             layout->set_has_static_tls();
3004             if (optimized_type == tls::TLSOPT_NONE)
3005               {
3006                 // Create a GOT entry for the tp-relative offset.
3007                 Output_data_got<64, false>* got
3008                     = target->got_section(symtab, layout);
3009                 got->add_global_with_rel(gsym, GOT_TYPE_TLS_OFFSET,
3010                                          target->rela_dyn_section(layout),
3011                                          elfcpp::R_X86_64_TPOFF64);
3012               }
3013             else if (optimized_type != tls::TLSOPT_TO_LE)
3014               unsupported_reloc_global(object, r_type, gsym);
3015             break;
3016
3017           case elfcpp::R_X86_64_TPOFF32:     // Local-exec
3018             layout->set_has_static_tls();
3019             if (parameters->options().shared())
3020               unsupported_reloc_global(object, r_type, gsym);
3021             break;
3022
3023           default:
3024             gold_unreachable();
3025           }
3026       }
3027       break;
3028
3029     case elfcpp::R_X86_64_SIZE32:
3030     case elfcpp::R_X86_64_SIZE64:
3031     default:
3032       gold_error(_("%s: unsupported reloc %u against global symbol %s"),
3033                  object->name().c_str(), r_type,
3034                  gsym->demangled_name().c_str());
3035       break;
3036     }
3037 }
3038
3039 template<int size>
3040 void
3041 Target_x86_64<size>::gc_process_relocs(Symbol_table* symtab,
3042                                        Layout* layout,
3043                                        Sized_relobj_file<size, false>* object,
3044                                        unsigned int data_shndx,
3045                                        unsigned int sh_type,
3046                                        const unsigned char* prelocs,
3047                                        size_t reloc_count,
3048                                        Output_section* output_section,
3049                                        bool needs_special_offset_handling,
3050                                        size_t local_symbol_count,
3051                                        const unsigned char* plocal_symbols)
3052 {
3053
3054   if (sh_type == elfcpp::SHT_REL)
3055     {
3056       return;
3057     }
3058
3059    gold::gc_process_relocs<size, false, Target_x86_64<size>, elfcpp::SHT_RELA,
3060                            typename Target_x86_64<size>::Scan,
3061                            typename Target_x86_64<size>::Relocatable_size_for_reloc>(
3062     symtab,
3063     layout,
3064     this,
3065     object,
3066     data_shndx,
3067     prelocs,
3068     reloc_count,
3069     output_section,
3070     needs_special_offset_handling,
3071     local_symbol_count,
3072     plocal_symbols);
3073
3074 }
3075 // Scan relocations for a section.
3076
3077 template<int size>
3078 void
3079 Target_x86_64<size>::scan_relocs(Symbol_table* symtab,
3080                                  Layout* layout,
3081                                  Sized_relobj_file<size, false>* object,
3082                                  unsigned int data_shndx,
3083                                  unsigned int sh_type,
3084                                  const unsigned char* prelocs,
3085                                  size_t reloc_count,
3086                                  Output_section* output_section,
3087                                  bool needs_special_offset_handling,
3088                                  size_t local_symbol_count,
3089                                  const unsigned char* plocal_symbols)
3090 {
3091   if (sh_type == elfcpp::SHT_REL)
3092     {
3093       gold_error(_("%s: unsupported REL reloc section"),
3094                  object->name().c_str());
3095       return;
3096     }
3097
3098   gold::scan_relocs<size, false, Target_x86_64<size>, elfcpp::SHT_RELA,
3099       typename Target_x86_64<size>::Scan>(
3100     symtab,
3101     layout,
3102     this,
3103     object,
3104     data_shndx,
3105     prelocs,
3106     reloc_count,
3107     output_section,
3108     needs_special_offset_handling,
3109     local_symbol_count,
3110     plocal_symbols);
3111 }
3112
3113 // Finalize the sections.
3114
3115 template<int size>
3116 void
3117 Target_x86_64<size>::do_finalize_sections(
3118     Layout* layout,
3119     const Input_objects*,
3120     Symbol_table* symtab)
3121 {
3122   const Reloc_section* rel_plt = (this->plt_ == NULL
3123                                   ? NULL
3124                                   : this->plt_->rela_plt());
3125   layout->add_target_dynamic_tags(false, this->got_plt_, rel_plt,
3126                                   this->rela_dyn_, true, false);
3127
3128   // Fill in some more dynamic tags.
3129   Output_data_dynamic* const odyn = layout->dynamic_data();
3130   if (odyn != NULL)
3131     {
3132       if (this->plt_ != NULL
3133           && this->plt_->output_section() != NULL
3134           && this->plt_->has_tlsdesc_entry())
3135         {
3136           unsigned int plt_offset = this->plt_->get_tlsdesc_plt_offset();
3137           unsigned int got_offset = this->plt_->get_tlsdesc_got_offset();
3138           this->got_->finalize_data_size();
3139           odyn->add_section_plus_offset(elfcpp::DT_TLSDESC_PLT,
3140                                         this->plt_, plt_offset);
3141           odyn->add_section_plus_offset(elfcpp::DT_TLSDESC_GOT,
3142                                         this->got_, got_offset);
3143         }
3144     }
3145
3146   // Emit any relocs we saved in an attempt to avoid generating COPY
3147   // relocs.
3148   if (this->copy_relocs_.any_saved_relocs())
3149     this->copy_relocs_.emit(this->rela_dyn_section(layout));
3150
3151   // Set the size of the _GLOBAL_OFFSET_TABLE_ symbol to the size of
3152   // the .got.plt section.
3153   Symbol* sym = this->global_offset_table_;
3154   if (sym != NULL)
3155     {
3156       uint64_t data_size = this->got_plt_->current_data_size();
3157       symtab->get_sized_symbol<size>(sym)->set_symsize(data_size);
3158     }
3159
3160   if (parameters->doing_static_link()
3161       && (this->plt_ == NULL || !this->plt_->has_irelative_section()))
3162     {
3163       // If linking statically, make sure that the __rela_iplt symbols
3164       // were defined if necessary, even if we didn't create a PLT.
3165       static const Define_symbol_in_segment syms[] =
3166         {
3167           {
3168             "__rela_iplt_start",        // name
3169             elfcpp::PT_LOAD,            // segment_type
3170             elfcpp::PF_W,               // segment_flags_set
3171             elfcpp::PF(0),              // segment_flags_clear
3172             0,                          // value
3173             0,                          // size
3174             elfcpp::STT_NOTYPE,         // type
3175             elfcpp::STB_GLOBAL,         // binding
3176             elfcpp::STV_HIDDEN,         // visibility
3177             0,                          // nonvis
3178             Symbol::SEGMENT_START,      // offset_from_base
3179             true                        // only_if_ref
3180           },
3181           {
3182             "__rela_iplt_end",          // name
3183             elfcpp::PT_LOAD,            // segment_type
3184             elfcpp::PF_W,               // segment_flags_set
3185             elfcpp::PF(0),              // segment_flags_clear
3186             0,                          // value
3187             0,                          // size
3188             elfcpp::STT_NOTYPE,         // type
3189             elfcpp::STB_GLOBAL,         // binding
3190             elfcpp::STV_HIDDEN,         // visibility
3191             0,                          // nonvis
3192             Symbol::SEGMENT_START,      // offset_from_base
3193             true                        // only_if_ref
3194           }
3195         };
3196
3197       symtab->define_symbols(layout, 2, syms,
3198                              layout->script_options()->saw_sections_clause());
3199     }
3200 }
3201
3202 // Perform a relocation.
3203
3204 template<int size>
3205 inline bool
3206 Target_x86_64<size>::Relocate::relocate(
3207     const Relocate_info<size, false>* relinfo,
3208     Target_x86_64<size>* target,
3209     Output_section*,
3210     size_t relnum,
3211     const elfcpp::Rela<size, false>& rela,
3212     unsigned int r_type,
3213     const Sized_symbol<size>* gsym,
3214     const Symbol_value<size>* psymval,
3215     unsigned char* view,
3216     typename elfcpp::Elf_types<size>::Elf_Addr address,
3217     section_size_type view_size)
3218 {
3219   if (this->skip_call_tls_get_addr_)
3220     {
3221       if ((r_type != elfcpp::R_X86_64_PLT32
3222            && r_type != elfcpp::R_X86_64_PC32)
3223           || gsym == NULL
3224           || strcmp(gsym->name(), "__tls_get_addr") != 0)
3225         {
3226           gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3227                                  _("missing expected TLS relocation"));
3228         }
3229       else
3230         {
3231           this->skip_call_tls_get_addr_ = false;
3232           return false;
3233         }
3234     }
3235
3236   if (view == NULL)
3237     return true;
3238
3239   const Sized_relobj_file<size, false>* object = relinfo->object;
3240
3241   // Pick the value to use for symbols defined in the PLT.
3242   Symbol_value<size> symval;
3243   if (gsym != NULL
3244       && gsym->use_plt_offset(Scan::get_reference_flags(r_type)))
3245     {
3246       symval.set_output_value(target->plt_address_for_global(gsym));
3247       psymval = &symval;
3248     }
3249   else if (gsym == NULL && psymval->is_ifunc_symbol())
3250     {
3251       unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
3252       if (object->local_has_plt_offset(r_sym))
3253         {
3254           symval.set_output_value(target->plt_address_for_local(object, r_sym));
3255           psymval = &symval;
3256         }
3257     }
3258
3259   const elfcpp::Elf_Xword addend = rela.get_r_addend();
3260
3261   // Get the GOT offset if needed.
3262   // The GOT pointer points to the end of the GOT section.
3263   // We need to subtract the size of the GOT section to get
3264   // the actual offset to use in the relocation.
3265   bool have_got_offset = false;
3266   unsigned int got_offset = 0;
3267   switch (r_type)
3268     {
3269     case elfcpp::R_X86_64_GOT32:
3270     case elfcpp::R_X86_64_GOT64:
3271     case elfcpp::R_X86_64_GOTPLT64:
3272     case elfcpp::R_X86_64_GOTPCREL:
3273     case elfcpp::R_X86_64_GOTPCREL64:
3274       if (gsym != NULL)
3275         {
3276           gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
3277           got_offset = gsym->got_offset(GOT_TYPE_STANDARD) - target->got_size();
3278         }
3279       else
3280         {
3281           unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
3282           gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD));
3283           got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD)
3284                         - target->got_size());
3285         }
3286       have_got_offset = true;
3287       break;
3288
3289     default:
3290       break;
3291     }
3292
3293   switch (r_type)
3294     {
3295     case elfcpp::R_X86_64_NONE:
3296     case elfcpp::R_X86_64_GNU_VTINHERIT:
3297     case elfcpp::R_X86_64_GNU_VTENTRY:
3298       break;
3299
3300     case elfcpp::R_X86_64_64:
3301       Relocate_functions<size, false>::rela64(view, object, psymval, addend);
3302       break;
3303
3304     case elfcpp::R_X86_64_PC64:
3305       Relocate_functions<size, false>::pcrela64(view, object, psymval, addend,
3306                                               address);
3307       break;
3308
3309     case elfcpp::R_X86_64_32:
3310       // FIXME: we need to verify that value + addend fits into 32 bits:
3311       //    uint64_t x = value + addend;
3312       //    x == static_cast<uint64_t>(static_cast<uint32_t>(x))
3313       // Likewise for other <=32-bit relocations (but see R_X86_64_32S).
3314       Relocate_functions<size, false>::rela32(view, object, psymval, addend);
3315       break;
3316
3317     case elfcpp::R_X86_64_32S:
3318       // FIXME: we need to verify that value + addend fits into 32 bits:
3319       //    int64_t x = value + addend;   // note this quantity is signed!
3320       //    x == static_cast<int64_t>(static_cast<int32_t>(x))
3321       Relocate_functions<size, false>::rela32(view, object, psymval, addend);
3322       break;
3323
3324     case elfcpp::R_X86_64_PC32:
3325       Relocate_functions<size, false>::pcrela32(view, object, psymval, addend,
3326                                                 address);
3327       break;
3328
3329     case elfcpp::R_X86_64_16:
3330       Relocate_functions<size, false>::rela16(view, object, psymval, addend);
3331       break;
3332
3333     case elfcpp::R_X86_64_PC16:
3334       Relocate_functions<size, false>::pcrela16(view, object, psymval, addend,
3335                                                 address);
3336       break;
3337
3338     case elfcpp::R_X86_64_8:
3339       Relocate_functions<size, false>::rela8(view, object, psymval, addend);
3340       break;
3341
3342     case elfcpp::R_X86_64_PC8:
3343       Relocate_functions<size, false>::pcrela8(view, object, psymval, addend,
3344                                                address);
3345       break;
3346
3347     case elfcpp::R_X86_64_PLT32:
3348       gold_assert(gsym == NULL
3349                   || gsym->has_plt_offset()
3350                   || gsym->final_value_is_known()
3351                   || (gsym->is_defined()
3352                       && !gsym->is_from_dynobj()
3353                       && !gsym->is_preemptible()));
3354       // Note: while this code looks the same as for R_X86_64_PC32, it
3355       // behaves differently because psymval was set to point to
3356       // the PLT entry, rather than the symbol, in Scan::global().
3357       Relocate_functions<size, false>::pcrela32(view, object, psymval, addend,
3358                                                 address);
3359       break;
3360
3361     case elfcpp::R_X86_64_PLTOFF64:
3362       {
3363         gold_assert(gsym);
3364         gold_assert(gsym->has_plt_offset()
3365                     || gsym->final_value_is_known());
3366         typename elfcpp::Elf_types<size>::Elf_Addr got_address;
3367         got_address = target->got_section(NULL, NULL)->address();
3368         Relocate_functions<size, false>::rela64(view, object, psymval,
3369                                                 addend - got_address);
3370       }
3371
3372     case elfcpp::R_X86_64_GOT32:
3373       gold_assert(have_got_offset);
3374       Relocate_functions<size, false>::rela32(view, got_offset, addend);
3375       break;
3376
3377     case elfcpp::R_X86_64_GOTPC32:
3378       {
3379         gold_assert(gsym);
3380         typename elfcpp::Elf_types<size>::Elf_Addr value;
3381         value = target->got_plt_section()->address();
3382         Relocate_functions<size, false>::pcrela32(view, value, addend, address);
3383       }
3384       break;
3385
3386     case elfcpp::R_X86_64_GOT64:
3387       // The ABI doc says "Like GOT64, but indicates a PLT entry is needed."
3388       // Since we always add a PLT entry, this is equivalent.
3389     case elfcpp::R_X86_64_GOTPLT64:
3390       gold_assert(have_got_offset);
3391       Relocate_functions<size, false>::rela64(view, got_offset, addend);
3392       break;
3393
3394     case elfcpp::R_X86_64_GOTPC64:
3395       {
3396         gold_assert(gsym);
3397         typename elfcpp::Elf_types<size>::Elf_Addr value;
3398         value = target->got_plt_section()->address();
3399         Relocate_functions<size, false>::pcrela64(view, value, addend, address);
3400       }
3401       break;
3402
3403     case elfcpp::R_X86_64_GOTOFF64:
3404       {
3405         typename elfcpp::Elf_types<size>::Elf_Addr value;
3406         value = (psymval->value(object, 0)
3407                  - target->got_plt_section()->address());
3408         Relocate_functions<size, false>::rela64(view, value, addend);
3409       }
3410       break;
3411
3412     case elfcpp::R_X86_64_GOTPCREL:
3413       {
3414         gold_assert(have_got_offset);
3415         typename elfcpp::Elf_types<size>::Elf_Addr value;
3416         value = target->got_plt_section()->address() + got_offset;
3417         Relocate_functions<size, false>::pcrela32(view, value, addend, address);
3418       }
3419       break;
3420
3421     case elfcpp::R_X86_64_GOTPCREL64:
3422       {
3423         gold_assert(have_got_offset);
3424         typename elfcpp::Elf_types<size>::Elf_Addr value;
3425         value = target->got_plt_section()->address() + got_offset;
3426         Relocate_functions<size, false>::pcrela64(view, value, addend, address);
3427       }
3428       break;
3429
3430     case elfcpp::R_X86_64_COPY:
3431     case elfcpp::R_X86_64_GLOB_DAT:
3432     case elfcpp::R_X86_64_JUMP_SLOT:
3433     case elfcpp::R_X86_64_RELATIVE:
3434     case elfcpp::R_X86_64_IRELATIVE:
3435       // These are outstanding tls relocs, which are unexpected when linking
3436     case elfcpp::R_X86_64_TPOFF64:
3437     case elfcpp::R_X86_64_DTPMOD64:
3438     case elfcpp::R_X86_64_TLSDESC:
3439       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3440                              _("unexpected reloc %u in object file"),
3441                              r_type);
3442       break;
3443
3444       // These are initial tls relocs, which are expected when linking
3445     case elfcpp::R_X86_64_TLSGD:            // Global-dynamic
3446     case elfcpp::R_X86_64_GOTPC32_TLSDESC:  // Global-dynamic (from ~oliva url)
3447     case elfcpp::R_X86_64_TLSDESC_CALL:
3448     case elfcpp::R_X86_64_TLSLD:            // Local-dynamic
3449     case elfcpp::R_X86_64_DTPOFF32:
3450     case elfcpp::R_X86_64_DTPOFF64:
3451     case elfcpp::R_X86_64_GOTTPOFF:         // Initial-exec
3452     case elfcpp::R_X86_64_TPOFF32:          // Local-exec
3453       this->relocate_tls(relinfo, target, relnum, rela, r_type, gsym, psymval,
3454                          view, address, view_size);
3455       break;
3456
3457     case elfcpp::R_X86_64_SIZE32:
3458     case elfcpp::R_X86_64_SIZE64:
3459     default:
3460       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3461                              _("unsupported reloc %u"),
3462                              r_type);
3463       break;
3464     }
3465
3466   return true;
3467 }
3468
3469 // Perform a TLS relocation.
3470
3471 template<int size>
3472 inline void
3473 Target_x86_64<size>::Relocate::relocate_tls(
3474     const Relocate_info<size, false>* relinfo,
3475     Target_x86_64<size>* target,
3476     size_t relnum,
3477     const elfcpp::Rela<size, false>& rela,
3478     unsigned int r_type,
3479     const Sized_symbol<size>* gsym,
3480     const Symbol_value<size>* psymval,
3481     unsigned char* view,
3482     typename elfcpp::Elf_types<size>::Elf_Addr address,
3483     section_size_type view_size)
3484 {
3485   Output_segment* tls_segment = relinfo->layout->tls_segment();
3486
3487   const Sized_relobj_file<size, false>* object = relinfo->object;
3488   const elfcpp::Elf_Xword addend = rela.get_r_addend();
3489   elfcpp::Shdr<size, false> data_shdr(relinfo->data_shdr);
3490   bool is_executable = (data_shdr.get_sh_flags() & elfcpp::SHF_EXECINSTR) != 0;
3491
3492   typename elfcpp::Elf_types<size>::Elf_Addr value = psymval->value(relinfo->object, 0);
3493
3494   const bool is_final = (gsym == NULL
3495                          ? !parameters->options().shared()
3496                          : gsym->final_value_is_known());
3497   tls::Tls_optimization optimized_type
3498       = Target_x86_64<size>::optimize_tls_reloc(is_final, r_type);
3499   switch (r_type)
3500     {
3501     case elfcpp::R_X86_64_TLSGD:            // Global-dynamic
3502       if (!is_executable && optimized_type == tls::TLSOPT_TO_LE)
3503         {
3504           // If this code sequence is used in a non-executable section,
3505           // we will not optimize the R_X86_64_DTPOFF32/64 relocation,
3506           // on the assumption that it's being used by itself in a debug
3507           // section.  Therefore, in the unlikely event that the code
3508           // sequence appears in a non-executable section, we simply
3509           // leave it unoptimized.
3510           optimized_type = tls::TLSOPT_NONE;
3511         }
3512       if (optimized_type == tls::TLSOPT_TO_LE)
3513         {
3514           if (tls_segment == NULL)
3515             {
3516               gold_assert(parameters->errors()->error_count() > 0
3517                           || issue_undefined_symbol_error(gsym));
3518               return;
3519             }
3520           this->tls_gd_to_le(relinfo, relnum, tls_segment,
3521                              rela, r_type, value, view,
3522                              view_size);
3523           break;
3524         }
3525       else
3526         {
3527           unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE
3528                                    ? GOT_TYPE_TLS_OFFSET
3529                                    : GOT_TYPE_TLS_PAIR);
3530           unsigned int got_offset;
3531           if (gsym != NULL)
3532             {
3533               gold_assert(gsym->has_got_offset(got_type));
3534               got_offset = gsym->got_offset(got_type) - target->got_size();
3535             }
3536           else
3537             {
3538               unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
3539               gold_assert(object->local_has_got_offset(r_sym, got_type));
3540               got_offset = (object->local_got_offset(r_sym, got_type)
3541                             - target->got_size());
3542             }
3543           if (optimized_type == tls::TLSOPT_TO_IE)
3544             {
3545               value = target->got_plt_section()->address() + got_offset;
3546               this->tls_gd_to_ie(relinfo, relnum, tls_segment, rela, r_type,
3547                                  value, view, address, view_size);
3548               break;
3549             }
3550           else if (optimized_type == tls::TLSOPT_NONE)
3551             {
3552               // Relocate the field with the offset of the pair of GOT
3553               // entries.
3554               value = target->got_plt_section()->address() + got_offset;
3555               Relocate_functions<size, false>::pcrela32(view, value, addend,
3556                                                         address);
3557               break;
3558             }
3559         }
3560       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3561                              _("unsupported reloc %u"), r_type);
3562       break;
3563
3564     case elfcpp::R_X86_64_GOTPC32_TLSDESC:  // Global-dynamic (from ~oliva url)
3565     case elfcpp::R_X86_64_TLSDESC_CALL:
3566       if (!is_executable && optimized_type == tls::TLSOPT_TO_LE)
3567         {
3568           // See above comment for R_X86_64_TLSGD.
3569           optimized_type = tls::TLSOPT_NONE;
3570         }
3571       if (optimized_type == tls::TLSOPT_TO_LE)
3572         {
3573           if (tls_segment == NULL)
3574             {
3575               gold_assert(parameters->errors()->error_count() > 0
3576                           || issue_undefined_symbol_error(gsym));
3577               return;
3578             }
3579           this->tls_desc_gd_to_le(relinfo, relnum, tls_segment,
3580                                   rela, r_type, value, view,
3581                                   view_size);
3582           break;
3583         }
3584       else
3585         {
3586           unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE
3587                                    ? GOT_TYPE_TLS_OFFSET
3588                                    : GOT_TYPE_TLS_DESC);
3589           unsigned int got_offset = 0;
3590           if (r_type == elfcpp::R_X86_64_GOTPC32_TLSDESC
3591               && optimized_type == tls::TLSOPT_NONE)
3592             {
3593               // We created GOT entries in the .got.tlsdesc portion of
3594               // the .got.plt section, but the offset stored in the
3595               // symbol is the offset within .got.tlsdesc.
3596               got_offset = (target->got_size()
3597                             + target->got_plt_section()->data_size());
3598             }
3599           if (gsym != NULL)
3600             {
3601               gold_assert(gsym->has_got_offset(got_type));
3602               got_offset += gsym->got_offset(got_type) - target->got_size();
3603             }
3604           else
3605             {
3606               unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
3607               gold_assert(object->local_has_got_offset(r_sym, got_type));
3608               got_offset += (object->local_got_offset(r_sym, got_type)
3609                              - target->got_size());
3610             }
3611           if (optimized_type == tls::TLSOPT_TO_IE)
3612             {
3613               if (tls_segment == NULL)
3614                 {
3615                   gold_assert(parameters->errors()->error_count() > 0
3616                               || issue_undefined_symbol_error(gsym));
3617                   return;
3618                 }
3619               value = target->got_plt_section()->address() + got_offset;
3620               this->tls_desc_gd_to_ie(relinfo, relnum, tls_segment,
3621                                       rela, r_type, value, view, address,
3622                                       view_size);
3623               break;
3624             }
3625           else if (optimized_type == tls::TLSOPT_NONE)
3626             {
3627               if (r_type == elfcpp::R_X86_64_GOTPC32_TLSDESC)
3628                 {
3629                   // Relocate the field with the offset of the pair of GOT
3630                   // entries.
3631                   value = target->got_plt_section()->address() + got_offset;
3632                   Relocate_functions<size, false>::pcrela32(view, value, addend,
3633                                                             address);
3634                 }
3635               break;
3636             }
3637         }
3638       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3639                              _("unsupported reloc %u"), r_type);
3640       break;
3641
3642     case elfcpp::R_X86_64_TLSLD:            // Local-dynamic
3643       if (!is_executable && optimized_type == tls::TLSOPT_TO_LE)
3644         {
3645           // See above comment for R_X86_64_TLSGD.
3646           optimized_type = tls::TLSOPT_NONE;
3647         }
3648       if (optimized_type == tls::TLSOPT_TO_LE)
3649         {
3650           if (tls_segment == NULL)
3651             {
3652               gold_assert(parameters->errors()->error_count() > 0
3653                           || issue_undefined_symbol_error(gsym));
3654               return;
3655             }
3656           this->tls_ld_to_le(relinfo, relnum, tls_segment, rela, r_type,
3657                              value, view, view_size);
3658           break;
3659         }
3660       else if (optimized_type == tls::TLSOPT_NONE)
3661         {
3662           // Relocate the field with the offset of the GOT entry for
3663           // the module index.
3664           unsigned int got_offset;
3665           got_offset = (target->got_mod_index_entry(NULL, NULL, NULL)
3666                         - target->got_size());
3667           value = target->got_plt_section()->address() + got_offset;
3668           Relocate_functions<size, false>::pcrela32(view, value, addend,
3669                                                     address);
3670           break;
3671         }
3672       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3673                              _("unsupported reloc %u"), r_type);
3674       break;
3675
3676     case elfcpp::R_X86_64_DTPOFF32:
3677       // This relocation type is used in debugging information.
3678       // In that case we need to not optimize the value.  If the
3679       // section is not executable, then we assume we should not
3680       // optimize this reloc.  See comments above for R_X86_64_TLSGD,
3681       // R_X86_64_GOTPC32_TLSDESC, R_X86_64_TLSDESC_CALL, and
3682       // R_X86_64_TLSLD.
3683       if (optimized_type == tls::TLSOPT_TO_LE && is_executable)
3684         {
3685           if (tls_segment == NULL)
3686             {
3687               gold_assert(parameters->errors()->error_count() > 0
3688                           || issue_undefined_symbol_error(gsym));
3689               return;
3690             }
3691           value -= tls_segment->memsz();
3692         }
3693       Relocate_functions<size, false>::rela32(view, value, addend);
3694       break;
3695
3696     case elfcpp::R_X86_64_DTPOFF64:
3697       // See R_X86_64_DTPOFF32, just above, for why we check for is_executable.
3698       if (optimized_type == tls::TLSOPT_TO_LE && is_executable)
3699         {
3700           if (tls_segment == NULL)
3701             {
3702               gold_assert(parameters->errors()->error_count() > 0
3703                           || issue_undefined_symbol_error(gsym));
3704               return;
3705             }
3706           value -= tls_segment->memsz();
3707         }
3708       Relocate_functions<size, false>::rela64(view, value, addend);
3709       break;
3710
3711     case elfcpp::R_X86_64_GOTTPOFF:         // Initial-exec
3712       if (optimized_type == tls::TLSOPT_TO_LE)
3713         {
3714           if (tls_segment == NULL)
3715             {
3716               gold_assert(parameters->errors()->error_count() > 0
3717                           || issue_undefined_symbol_error(gsym));
3718               return;
3719             }
3720           Target_x86_64<size>::Relocate::tls_ie_to_le(relinfo, relnum,
3721                                                       tls_segment, rela,
3722                                                       r_type, value, view,
3723                                                       view_size);
3724           break;
3725         }
3726       else if (optimized_type == tls::TLSOPT_NONE)
3727         {
3728           // Relocate the field with the offset of the GOT entry for
3729           // the tp-relative offset of the symbol.
3730           unsigned int got_offset;
3731           if (gsym != NULL)
3732             {
3733               gold_assert(gsym->has_got_offset(GOT_TYPE_TLS_OFFSET));
3734               got_offset = (gsym->got_offset(GOT_TYPE_TLS_OFFSET)
3735                             - target->got_size());
3736             }
3737           else
3738             {
3739               unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
3740               gold_assert(object->local_has_got_offset(r_sym,
3741                                                        GOT_TYPE_TLS_OFFSET));
3742               got_offset = (object->local_got_offset(r_sym, GOT_TYPE_TLS_OFFSET)
3743                             - target->got_size());
3744             }
3745           value = target->got_plt_section()->address() + got_offset;
3746           Relocate_functions<size, false>::pcrela32(view, value, addend,
3747                                                     address);
3748           break;
3749         }
3750       gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3751                              _("unsupported reloc type %u"),
3752                              r_type);
3753       break;
3754
3755     case elfcpp::R_X86_64_TPOFF32:          // Local-exec
3756       if (tls_segment == NULL)
3757         {
3758           gold_assert(parameters->errors()->error_count() > 0
3759                       || issue_undefined_symbol_error(gsym));
3760           return;
3761         }
3762       value -= tls_segment->memsz();
3763       Relocate_functions<size, false>::rela32(view, value, addend);
3764       break;
3765     }
3766 }
3767
3768 // Do a relocation in which we convert a TLS General-Dynamic to an
3769 // Initial-Exec.
3770
3771 template<int size>
3772 inline void
3773 Target_x86_64<size>::Relocate::tls_gd_to_ie(
3774     const Relocate_info<size, false>* relinfo,
3775     size_t relnum,
3776     Output_segment*,
3777     const elfcpp::Rela<size, false>& rela,
3778     unsigned int,
3779     typename elfcpp::Elf_types<size>::Elf_Addr value,
3780     unsigned char* view,
3781     typename elfcpp::Elf_types<size>::Elf_Addr address,
3782     section_size_type view_size)
3783 {
3784   // For SIZE == 64:
3785   //    .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
3786   //    .word 0x6666; rex64; call __tls_get_addr
3787   //    ==> movq %fs:0,%rax; addq x@gottpoff(%rip),%rax
3788   // For SIZE == 32:
3789   //    leaq foo@tlsgd(%rip),%rdi;
3790   //    .word 0x6666; rex64; call __tls_get_addr
3791   //    ==> movl %fs:0,%eax; addq x@gottpoff(%rip),%rax
3792
3793   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 12);
3794   tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3795                  (memcmp(view + 4, "\x66\x66\x48\xe8", 4) == 0));
3796
3797   if (size == 64)
3798     {
3799       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size,
3800                        -4);
3801       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3802                      (memcmp(view - 4, "\x66\x48\x8d\x3d", 4) == 0));
3803       memcpy(view - 4, "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x03\x05\0\0\0\0",
3804              16);
3805     }
3806   else
3807     {
3808       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size,
3809                        -3);
3810       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3811                      (memcmp(view - 3, "\x48\x8d\x3d", 3) == 0));
3812       memcpy(view - 3, "\x64\x8b\x04\x25\0\0\0\0\x48\x03\x05\0\0\0\0",
3813              15);
3814     }
3815
3816   const elfcpp::Elf_Xword addend = rela.get_r_addend();
3817   Relocate_functions<size, false>::pcrela32(view + 8, value, addend - 8,
3818                                             address);
3819
3820   // The next reloc should be a PLT32 reloc against __tls_get_addr.
3821   // We can skip it.
3822   this->skip_call_tls_get_addr_ = true;
3823 }
3824
3825 // Do a relocation in which we convert a TLS General-Dynamic to a
3826 // Local-Exec.
3827
3828 template<int size>
3829 inline void
3830 Target_x86_64<size>::Relocate::tls_gd_to_le(
3831     const Relocate_info<size, false>* relinfo,
3832     size_t relnum,
3833     Output_segment* tls_segment,
3834     const elfcpp::Rela<size, false>& rela,
3835     unsigned int,
3836     typename elfcpp::Elf_types<size>::Elf_Addr value,
3837     unsigned char* view,
3838     section_size_type view_size)
3839 {
3840   // For SIZE == 64:
3841   //    .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
3842   //    .word 0x6666; rex64; call __tls_get_addr
3843   //    ==> movq %fs:0,%rax; leaq x@tpoff(%rax),%rax
3844   // For SIZE == 32:
3845   //    leaq foo@tlsgd(%rip),%rdi;
3846   //    .word 0x6666; rex64; call __tls_get_addr
3847   //    ==> movl %fs:0,%eax; leaq x@tpoff(%rax),%rax
3848
3849   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 12);
3850   tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3851                  (memcmp(view + 4, "\x66\x66\x48\xe8", 4) == 0));
3852
3853   if (size == 64)
3854     {
3855       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size,
3856                        -4);
3857       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3858                      (memcmp(view - 4, "\x66\x48\x8d\x3d", 4) == 0));
3859       memcpy(view - 4, "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0\0",
3860              16);
3861     }
3862   else
3863     {
3864       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size,
3865                        -3);
3866       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3867                      (memcmp(view - 3, "\x48\x8d\x3d", 3) == 0));
3868
3869       memcpy(view - 3, "\x64\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0\0",
3870              15);
3871     }
3872
3873   value -= tls_segment->memsz();
3874   Relocate_functions<size, false>::rela32(view + 8, value, 0);
3875
3876   // The next reloc should be a PLT32 reloc against __tls_get_addr.
3877   // We can skip it.
3878   this->skip_call_tls_get_addr_ = true;
3879 }
3880
3881 // Do a TLSDESC-style General-Dynamic to Initial-Exec transition.
3882
3883 template<int size>
3884 inline void
3885 Target_x86_64<size>::Relocate::tls_desc_gd_to_ie(
3886     const Relocate_info<size, false>* relinfo,
3887     size_t relnum,
3888     Output_segment*,
3889     const elfcpp::Rela<size, false>& rela,
3890     unsigned int r_type,
3891     typename elfcpp::Elf_types<size>::Elf_Addr value,
3892     unsigned char* view,
3893     typename elfcpp::Elf_types<size>::Elf_Addr address,
3894     section_size_type view_size)
3895 {
3896   if (r_type == elfcpp::R_X86_64_GOTPC32_TLSDESC)
3897     {
3898       // leaq foo@tlsdesc(%rip), %rax
3899       // ==> movq foo@gottpoff(%rip), %rax
3900       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -3);
3901       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 4);
3902       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3903                      view[-3] == 0x48 && view[-2] == 0x8d && view[-1] == 0x05);
3904       view[-2] = 0x8b;
3905       const elfcpp::Elf_Xword addend = rela.get_r_addend();
3906       Relocate_functions<size, false>::pcrela32(view, value, addend, address);
3907     }
3908   else
3909     {
3910       // call *foo@tlscall(%rax)
3911       // ==> nop; nop
3912       gold_assert(r_type == elfcpp::R_X86_64_TLSDESC_CALL);
3913       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 2);
3914       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3915                      view[0] == 0xff && view[1] == 0x10);
3916       view[0] = 0x66;
3917       view[1] = 0x90;
3918     }
3919 }
3920
3921 // Do a TLSDESC-style General-Dynamic to Local-Exec transition.
3922
3923 template<int size>
3924 inline void
3925 Target_x86_64<size>::Relocate::tls_desc_gd_to_le(
3926     const Relocate_info<size, false>* relinfo,
3927     size_t relnum,
3928     Output_segment* tls_segment,
3929     const elfcpp::Rela<size, false>& rela,
3930     unsigned int r_type,
3931     typename elfcpp::Elf_types<size>::Elf_Addr value,
3932     unsigned char* view,
3933     section_size_type view_size)
3934 {
3935   if (r_type == elfcpp::R_X86_64_GOTPC32_TLSDESC)
3936     {
3937       // leaq foo@tlsdesc(%rip), %rax
3938       // ==> movq foo@tpoff, %rax
3939       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -3);
3940       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 4);
3941       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3942                      view[-3] == 0x48 && view[-2] == 0x8d && view[-1] == 0x05);
3943       view[-2] = 0xc7;
3944       view[-1] = 0xc0;
3945       value -= tls_segment->memsz();
3946       Relocate_functions<size, false>::rela32(view, value, 0);
3947     }
3948   else
3949     {
3950       // call *foo@tlscall(%rax)
3951       // ==> nop; nop
3952       gold_assert(r_type == elfcpp::R_X86_64_TLSDESC_CALL);
3953       tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 2);
3954       tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3955                      view[0] == 0xff && view[1] == 0x10);
3956       view[0] = 0x66;
3957       view[1] = 0x90;
3958     }
3959 }
3960
3961 template<int size>
3962 inline void
3963 Target_x86_64<size>::Relocate::tls_ld_to_le(
3964     const Relocate_info<size, false>* relinfo,
3965     size_t relnum,
3966     Output_segment*,
3967     const elfcpp::Rela<size, false>& rela,
3968     unsigned int,
3969     typename elfcpp::Elf_types<size>::Elf_Addr,
3970     unsigned char* view,
3971     section_size_type view_size)
3972 {
3973   // leaq foo@tlsld(%rip),%rdi; call __tls_get_addr@plt;
3974   // For SIZE == 64:
3975   // ... leq foo@dtpoff(%rax),%reg
3976   // ==> .word 0x6666; .byte 0x66; movq %fs:0,%rax ... leaq x@tpoff(%rax),%rdx
3977   // For SIZE == 32:
3978   // ... leq foo@dtpoff(%rax),%reg
3979   // ==> nopl 0x0(%rax); movl %fs:0,%eax ... leaq x@tpoff(%rax),%rdx
3980
3981   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -3);
3982   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 9);
3983
3984   tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3985                  view[-3] == 0x48 && view[-2] == 0x8d && view[-1] == 0x3d);
3986
3987   tls::check_tls(relinfo, relnum, rela.get_r_offset(), view[4] == 0xe8);
3988
3989   if (size == 64)
3990     memcpy(view - 3, "\x66\x66\x66\x64\x48\x8b\x04\x25\0\0\0\0", 12);
3991   else
3992     memcpy(view - 3, "\x0f\x1f\x40\x00\x64\x8b\x04\x25\0\0\0\0", 12);
3993
3994   // The next reloc should be a PLT32 reloc against __tls_get_addr.
3995   // We can skip it.
3996   this->skip_call_tls_get_addr_ = true;
3997 }
3998
3999 // Do a relocation in which we convert a TLS Initial-Exec to a
4000 // Local-Exec.
4001
4002 template<int size>
4003 inline void
4004 Target_x86_64<size>::Relocate::tls_ie_to_le(
4005     const Relocate_info<size, false>* relinfo,
4006     size_t relnum,
4007     Output_segment* tls_segment,
4008     const elfcpp::Rela<size, false>& rela,
4009     unsigned int,
4010     typename elfcpp::Elf_types<size>::Elf_Addr value,
4011     unsigned char* view,
4012     section_size_type view_size)
4013 {
4014   // We need to examine the opcodes to figure out which instruction we
4015   // are looking at.
4016
4017   // movq foo@gottpoff(%rip),%reg  ==>  movq $YY,%reg
4018   // addq foo@gottpoff(%rip),%reg  ==>  addq $YY,%reg
4019
4020   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -3);
4021   tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 4);
4022
4023   unsigned char op1 = view[-3];
4024   unsigned char op2 = view[-2];
4025   unsigned char op3 = view[-1];
4026   unsigned char reg = op3 >> 3;
4027
4028   if (op2 == 0x8b)
4029     {
4030       // movq
4031       if (op1 == 0x4c)
4032         view[-3] = 0x49;
4033       view[-2] = 0xc7;
4034       view[-1] = 0xc0 | reg;
4035     }
4036   else if (reg == 4)
4037     {
4038       // Special handling for %rsp.
4039       if (op1 == 0x4c)
4040         view[-3] = 0x49;
4041       view[-2] = 0x81;
4042       view[-1] = 0xc0 | reg;
4043     }
4044   else
4045     {
4046       // addq
4047       if (op1 == 0x4c)
4048         view[-3] = 0x4d;
4049       view[-2] = 0x8d;
4050       view[-1] = 0x80 | reg | (reg << 3);
4051     }
4052
4053   value -= tls_segment->memsz();
4054   Relocate_functions<size, false>::rela32(view, value, 0);
4055 }
4056
4057 // Relocate section data.
4058
4059 template<int size>
4060 void
4061 Target_x86_64<size>::relocate_section(
4062     const Relocate_info<size, false>* relinfo,
4063     unsigned int sh_type,
4064     const unsigned char* prelocs,
4065     size_t reloc_count,
4066     Output_section* output_section,
4067     bool needs_special_offset_handling,
4068     unsigned char* view,
4069     typename elfcpp::Elf_types<size>::Elf_Addr address,
4070     section_size_type view_size,
4071     const Reloc_symbol_changes* reloc_symbol_changes)
4072 {
4073   gold_assert(sh_type == elfcpp::SHT_RELA);
4074
4075   gold::relocate_section<size, false, Target_x86_64<size>, elfcpp::SHT_RELA,
4076                          typename Target_x86_64<size>::Relocate,
4077                          gold::Default_comdat_behavior>(
4078     relinfo,
4079     this,
4080     prelocs,
4081     reloc_count,
4082     output_section,
4083     needs_special_offset_handling,
4084     view,
4085     address,
4086     view_size,
4087     reloc_symbol_changes);
4088 }
4089
4090 // Apply an incremental relocation.  Incremental relocations always refer
4091 // to global symbols.
4092
4093 template<int size>
4094 void
4095 Target_x86_64<size>::apply_relocation(
4096     const Relocate_info<size, false>* relinfo,
4097     typename elfcpp::Elf_types<size>::Elf_Addr r_offset,
4098     unsigned int r_type,
4099     typename elfcpp::Elf_types<size>::Elf_Swxword r_addend,
4100     const Symbol* gsym,
4101     unsigned char* view,
4102     typename elfcpp::Elf_types<size>::Elf_Addr address,
4103     section_size_type view_size)
4104 {
4105   gold::apply_relocation<size, false, Target_x86_64<size>,
4106                          typename Target_x86_64<size>::Relocate>(
4107     relinfo,
4108     this,
4109     r_offset,
4110     r_type,
4111     r_addend,
4112     gsym,
4113     view,
4114     address,
4115     view_size);
4116 }
4117
4118 // Return the size of a relocation while scanning during a relocatable
4119 // link.
4120
4121 template<int size>
4122 unsigned int
4123 Target_x86_64<size>::Relocatable_size_for_reloc::get_size_for_reloc(
4124     unsigned int r_type,
4125     Relobj* object)
4126 {
4127   switch (r_type)
4128     {
4129     case elfcpp::R_X86_64_NONE:
4130     case elfcpp::R_X86_64_GNU_VTINHERIT:
4131     case elfcpp::R_X86_64_GNU_VTENTRY:
4132     case elfcpp::R_X86_64_TLSGD:            // Global-dynamic
4133     case elfcpp::R_X86_64_GOTPC32_TLSDESC:  // Global-dynamic (from ~oliva url)
4134     case elfcpp::R_X86_64_TLSDESC_CALL:
4135     case elfcpp::R_X86_64_TLSLD:            // Local-dynamic
4136     case elfcpp::R_X86_64_DTPOFF32:
4137     case elfcpp::R_X86_64_DTPOFF64:
4138     case elfcpp::R_X86_64_GOTTPOFF:         // Initial-exec
4139     case elfcpp::R_X86_64_TPOFF32:          // Local-exec
4140       return 0;
4141
4142     case elfcpp::R_X86_64_64:
4143     case elfcpp::R_X86_64_PC64:
4144     case elfcpp::R_X86_64_GOTOFF64:
4145     case elfcpp::R_X86_64_GOTPC64:
4146     case elfcpp::R_X86_64_PLTOFF64:
4147     case elfcpp::R_X86_64_GOT64:
4148     case elfcpp::R_X86_64_GOTPCREL64:
4149     case elfcpp::R_X86_64_GOTPCREL:
4150     case elfcpp::R_X86_64_GOTPLT64:
4151       return 8;
4152
4153     case elfcpp::R_X86_64_32:
4154     case elfcpp::R_X86_64_32S:
4155     case elfcpp::R_X86_64_PC32:
4156     case elfcpp::R_X86_64_PLT32:
4157     case elfcpp::R_X86_64_GOTPC32:
4158     case elfcpp::R_X86_64_GOT32:
4159       return 4;
4160
4161     case elfcpp::R_X86_64_16:
4162     case elfcpp::R_X86_64_PC16:
4163       return 2;
4164
4165     case elfcpp::R_X86_64_8:
4166     case elfcpp::R_X86_64_PC8:
4167       return 1;
4168
4169     case elfcpp::R_X86_64_COPY:
4170     case elfcpp::R_X86_64_GLOB_DAT:
4171     case elfcpp::R_X86_64_JUMP_SLOT:
4172     case elfcpp::R_X86_64_RELATIVE:
4173     case elfcpp::R_X86_64_IRELATIVE:
4174       // These are outstanding tls relocs, which are unexpected when linking
4175     case elfcpp::R_X86_64_TPOFF64:
4176     case elfcpp::R_X86_64_DTPMOD64:
4177     case elfcpp::R_X86_64_TLSDESC:
4178       object->error(_("unexpected reloc %u in object file"), r_type);
4179       return 0;
4180
4181     case elfcpp::R_X86_64_SIZE32:
4182     case elfcpp::R_X86_64_SIZE64:
4183     default:
4184       object->error(_("unsupported reloc %u against local symbol"), r_type);
4185       return 0;
4186     }
4187 }
4188
4189 // Scan the relocs during a relocatable link.
4190
4191 template<int size>
4192 void
4193 Target_x86_64<size>::scan_relocatable_relocs(
4194     Symbol_table* symtab,
4195     Layout* layout,
4196     Sized_relobj_file<size, false>* object,
4197     unsigned int data_shndx,
4198     unsigned int sh_type,
4199     const unsigned char* prelocs,
4200     size_t reloc_count,
4201     Output_section* output_section,
4202     bool needs_special_offset_handling,
4203     size_t local_symbol_count,
4204     const unsigned char* plocal_symbols,
4205     Relocatable_relocs* rr)
4206 {
4207   gold_assert(sh_type == elfcpp::SHT_RELA);
4208
4209   typedef gold::Default_scan_relocatable_relocs<elfcpp::SHT_RELA,
4210     Relocatable_size_for_reloc> Scan_relocatable_relocs;
4211
4212   gold::scan_relocatable_relocs<size, false, elfcpp::SHT_RELA,
4213       Scan_relocatable_relocs>(
4214     symtab,
4215     layout,
4216     object,
4217     data_shndx,
4218     prelocs,
4219     reloc_count,
4220     output_section,
4221     needs_special_offset_handling,
4222     local_symbol_count,
4223     plocal_symbols,
4224     rr);
4225 }
4226
4227 // Relocate a section during a relocatable link.
4228
4229 template<int size>
4230 void
4231 Target_x86_64<size>::relocate_relocs(
4232     const Relocate_info<size, false>* relinfo,
4233     unsigned int sh_type,
4234     const unsigned char* prelocs,
4235     size_t reloc_count,
4236     Output_section* output_section,
4237     typename elfcpp::Elf_types<size>::Elf_Off offset_in_output_section,
4238     const Relocatable_relocs* rr,
4239     unsigned char* view,
4240     typename elfcpp::Elf_types<size>::Elf_Addr view_address,
4241     section_size_type view_size,
4242     unsigned char* reloc_view,
4243     section_size_type reloc_view_size)
4244 {
4245   gold_assert(sh_type == elfcpp::SHT_RELA);
4246
4247   gold::relocate_relocs<size, false, elfcpp::SHT_RELA>(
4248     relinfo,
4249     prelocs,
4250     reloc_count,
4251     output_section,
4252     offset_in_output_section,
4253     rr,
4254     view,
4255     view_address,
4256     view_size,
4257     reloc_view,
4258     reloc_view_size);
4259 }
4260
4261 // Return the value to use for a dynamic which requires special
4262 // treatment.  This is how we support equality comparisons of function
4263 // pointers across shared library boundaries, as described in the
4264 // processor specific ABI supplement.
4265
4266 template<int size>
4267 uint64_t
4268 Target_x86_64<size>::do_dynsym_value(const Symbol* gsym) const
4269 {
4270   gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset());
4271   return this->plt_address_for_global(gsym);
4272 }
4273
4274 // Return a string used to fill a code section with nops to take up
4275 // the specified length.
4276
4277 template<int size>
4278 std::string
4279 Target_x86_64<size>::do_code_fill(section_size_type length) const
4280 {
4281   if (length >= 16)
4282     {
4283       // Build a jmpq instruction to skip over the bytes.
4284       unsigned char jmp[5];
4285       jmp[0] = 0xe9;
4286       elfcpp::Swap_unaligned<32, false>::writeval(jmp + 1, length - 5);
4287       return (std::string(reinterpret_cast<char*>(&jmp[0]), 5)
4288               + std::string(length - 5, static_cast<char>(0x90)));
4289     }
4290
4291   // Nop sequences of various lengths.
4292   const char nop1[1] = { '\x90' };                 // nop
4293   const char nop2[2] = { '\x66', '\x90' };         // xchg %ax %ax
4294   const char nop3[3] = { '\x0f', '\x1f', '\x00' }; // nop (%rax)
4295   const char nop4[4] = { '\x0f', '\x1f', '\x40',   // nop 0(%rax)
4296                          '\x00'};
4297   const char nop5[5] = { '\x0f', '\x1f', '\x44',   // nop 0(%rax,%rax,1)
4298                          '\x00', '\x00' };
4299   const char nop6[6] = { '\x66', '\x0f', '\x1f',   // nopw 0(%rax,%rax,1)
4300                          '\x44', '\x00', '\x00' };
4301   const char nop7[7] = { '\x0f', '\x1f', '\x80',   // nopl 0L(%rax)
4302                          '\x00', '\x00', '\x00',
4303                          '\x00' };
4304   const char nop8[8] = { '\x0f', '\x1f', '\x84',   // nopl 0L(%rax,%rax,1)
4305                          '\x00', '\x00', '\x00',
4306                          '\x00', '\x00' };
4307   const char nop9[9] = { '\x66', '\x0f', '\x1f',   // nopw 0L(%rax,%rax,1)
4308                          '\x84', '\x00', '\x00',
4309                          '\x00', '\x00', '\x00' };
4310   const char nop10[10] = { '\x66', '\x2e', '\x0f', // nopw %cs:0L(%rax,%rax,1)
4311                            '\x1f', '\x84', '\x00',
4312                            '\x00', '\x00', '\x00',
4313                            '\x00' };
4314   const char nop11[11] = { '\x66', '\x66', '\x2e', // data16
4315                            '\x0f', '\x1f', '\x84', // nopw %cs:0L(%rax,%rax,1)
4316                            '\x00', '\x00', '\x00',
4317                            '\x00', '\x00' };
4318   const char nop12[12] = { '\x66', '\x66', '\x66', // data16; data16
4319                            '\x2e', '\x0f', '\x1f', // nopw %cs:0L(%rax,%rax,1)
4320                            '\x84', '\x00', '\x00',
4321                            '\x00', '\x00', '\x00' };
4322   const char nop13[13] = { '\x66', '\x66', '\x66', // data16; data16; data16
4323                            '\x66', '\x2e', '\x0f', // nopw %cs:0L(%rax,%rax,1)
4324                            '\x1f', '\x84', '\x00',
4325                            '\x00', '\x00', '\x00',
4326                            '\x00' };
4327   const char nop14[14] = { '\x66', '\x66', '\x66', // data16; data16; data16
4328                            '\x66', '\x66', '\x2e', // data16
4329                            '\x0f', '\x1f', '\x84', // nopw %cs:0L(%rax,%rax,1)
4330                            '\x00', '\x00', '\x00',
4331                            '\x00', '\x00' };
4332   const char nop15[15] = { '\x66', '\x66', '\x66', // data16; data16; data16
4333                            '\x66', '\x66', '\x66', // data16; data16
4334                            '\x2e', '\x0f', '\x1f', // nopw %cs:0L(%rax,%rax,1)
4335                            '\x84', '\x00', '\x00',
4336                            '\x00', '\x00', '\x00' };
4337
4338   const char* nops[16] = {
4339     NULL,
4340     nop1, nop2, nop3, nop4, nop5, nop6, nop7,
4341     nop8, nop9, nop10, nop11, nop12, nop13, nop14, nop15
4342   };
4343
4344   return std::string(nops[length], length);
4345 }
4346
4347 // Return the addend to use for a target specific relocation.  The
4348 // only target specific relocation is R_X86_64_TLSDESC for a local
4349 // symbol.  We want to set the addend is the offset of the local
4350 // symbol in the TLS segment.
4351
4352 template<int size>
4353 uint64_t
4354 Target_x86_64<size>::do_reloc_addend(void* arg, unsigned int r_type,
4355                                      uint64_t) const
4356 {
4357   gold_assert(r_type == elfcpp::R_X86_64_TLSDESC);
4358   uintptr_t intarg = reinterpret_cast<uintptr_t>(arg);
4359   gold_assert(intarg < this->tlsdesc_reloc_info_.size());
4360   const Tlsdesc_info& ti(this->tlsdesc_reloc_info_[intarg]);
4361   const Symbol_value<size>* psymval = ti.object->local_symbol(ti.r_sym);
4362   gold_assert(psymval->is_tls_symbol());
4363   // The value of a TLS symbol is the offset in the TLS segment.
4364   return psymval->value(ti.object, 0);
4365 }
4366
4367 // Return the value to use for the base of a DW_EH_PE_datarel offset
4368 // in an FDE.  Solaris and SVR4 use DW_EH_PE_datarel because their
4369 // assembler can not write out the difference between two labels in
4370 // different sections, so instead of using a pc-relative value they
4371 // use an offset from the GOT.
4372
4373 template<int size>
4374 uint64_t
4375 Target_x86_64<size>::do_ehframe_datarel_base() const
4376 {
4377   gold_assert(this->global_offset_table_ != NULL);
4378   Symbol* sym = this->global_offset_table_;
4379   Sized_symbol<size>* ssym = static_cast<Sized_symbol<size>*>(sym);
4380   return ssym->value();
4381 }
4382
4383 // FNOFFSET in section SHNDX in OBJECT is the start of a function
4384 // compiled with -fsplit-stack.  The function calls non-split-stack
4385 // code.  We have to change the function so that it always ensures
4386 // that it has enough stack space to run some random function.
4387
4388 template<int size>
4389 void
4390 Target_x86_64<size>::do_calls_non_split(Relobj* object, unsigned int shndx,
4391                                         section_offset_type fnoffset,
4392                                         section_size_type fnsize,
4393                                         unsigned char* view,
4394                                         section_size_type view_size,
4395                                         std::string* from,
4396                                         std::string* to) const
4397 {
4398   // The function starts with a comparison of the stack pointer and a
4399   // field in the TCB.  This is followed by a jump.
4400
4401   // cmp %fs:NN,%rsp
4402   if (this->match_view(view, view_size, fnoffset, "\x64\x48\x3b\x24\x25", 5)
4403       && fnsize > 9)
4404     {
4405       // We will call __morestack if the carry flag is set after this
4406       // comparison.  We turn the comparison into an stc instruction
4407       // and some nops.
4408       view[fnoffset] = '\xf9';
4409       this->set_view_to_nop(view, view_size, fnoffset + 1, 8);
4410     }
4411   // lea NN(%rsp),%r10
4412   // lea NN(%rsp),%r11
4413   else if ((this->match_view(view, view_size, fnoffset,
4414                              "\x4c\x8d\x94\x24", 4)
4415             || this->match_view(view, view_size, fnoffset,
4416                                 "\x4c\x8d\x9c\x24", 4))
4417            && fnsize > 8)
4418     {
4419       // This is loading an offset from the stack pointer for a
4420       // comparison.  The offset is negative, so we decrease the
4421       // offset by the amount of space we need for the stack.  This
4422       // means we will avoid calling __morestack if there happens to
4423       // be plenty of space on the stack already.
4424       unsigned char* pval = view + fnoffset + 4;
4425       uint32_t val = elfcpp::Swap_unaligned<32, false>::readval(pval);
4426       val -= parameters->options().split_stack_adjust_size();
4427       elfcpp::Swap_unaligned<32, false>::writeval(pval, val);
4428     }
4429   else
4430     {
4431       if (!object->has_no_split_stack())
4432         object->error(_("failed to match split-stack sequence at "
4433                         "section %u offset %0zx"),
4434                       shndx, static_cast<size_t>(fnoffset));
4435       return;
4436     }
4437
4438   // We have to change the function so that it calls
4439   // __morestack_non_split instead of __morestack.  The former will
4440   // allocate additional stack space.
4441   *from = "__morestack";
4442   *to = "__morestack_non_split";
4443 }
4444
4445 // The selector for x86_64 object files.  Note this is never instantiated
4446 // directly.  It's only used in Target_selector_x86_64_nacl, below.
4447
4448 template<int size>
4449 class Target_selector_x86_64 : public Target_selector_freebsd
4450 {
4451 public:
4452   Target_selector_x86_64()
4453     : Target_selector_freebsd(elfcpp::EM_X86_64, size, false,
4454                               (size == 64
4455                                ? "elf64-x86-64" : "elf32-x86-64"),
4456                               (size == 64
4457                                ? "elf64-x86-64-freebsd"
4458                                : "elf32-x86-64-freebsd"),
4459                               (size == 64 ? "elf_x86_64" : "elf32_x86_64"))
4460   { }
4461
4462   Target*
4463   do_instantiate_target()
4464   { return new Target_x86_64<size>(); }
4465
4466 };
4467
4468 // NaCl variant.  It uses different PLT contents.
4469
4470 template<int size>
4471 class Output_data_plt_x86_64_nacl : public Output_data_plt_x86_64<size>
4472 {
4473  public:
4474   Output_data_plt_x86_64_nacl(Layout* layout,
4475                               Output_data_got<64, false>* got,
4476                               Output_data_space* got_plt,
4477                               Output_data_space* got_irelative)
4478     : Output_data_plt_x86_64<size>(layout, plt_entry_size,
4479                                    got, got_plt, got_irelative)
4480   { }
4481
4482   Output_data_plt_x86_64_nacl(Layout* layout,
4483                               Output_data_got<64, false>* got,
4484                               Output_data_space* got_plt,
4485                               Output_data_space* got_irelative,
4486                               unsigned int plt_count)
4487     : Output_data_plt_x86_64<size>(layout, plt_entry_size,
4488                                    got, got_plt, got_irelative,
4489                                    plt_count)
4490   { }
4491
4492  protected:
4493   virtual unsigned int
4494   do_get_plt_entry_size() const
4495   { return plt_entry_size; }
4496
4497   virtual void
4498   do_add_eh_frame(Layout* layout)
4499   {
4500     layout->add_eh_frame_for_plt(this,
4501                                  this->plt_eh_frame_cie,
4502                                  this->plt_eh_frame_cie_size,
4503                                  plt_eh_frame_fde,
4504                                  plt_eh_frame_fde_size);
4505   }
4506
4507   virtual void
4508   do_fill_first_plt_entry(unsigned char* pov,
4509                           typename elfcpp::Elf_types<size>::Elf_Addr got_addr,
4510                           typename elfcpp::Elf_types<size>::Elf_Addr plt_addr);
4511
4512   virtual unsigned int
4513   do_fill_plt_entry(unsigned char* pov,
4514                     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
4515                     typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
4516                     unsigned int got_offset,
4517                     unsigned int plt_offset,
4518                     unsigned int plt_index);
4519
4520   virtual void
4521   do_fill_tlsdesc_entry(unsigned char* pov,
4522                         typename elfcpp::Elf_types<size>::Elf_Addr got_address,
4523                         typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
4524                         typename elfcpp::Elf_types<size>::Elf_Addr got_base,
4525                         unsigned int tlsdesc_got_offset,
4526                         unsigned int plt_offset);
4527
4528  private:
4529   // The size of an entry in the PLT.
4530   static const int plt_entry_size = 64;
4531
4532   // The first entry in the PLT.
4533   static const unsigned char first_plt_entry[plt_entry_size];
4534
4535   // Other entries in the PLT for an executable.
4536   static const unsigned char plt_entry[plt_entry_size];
4537
4538   // The reserved TLSDESC entry in the PLT for an executable.
4539   static const unsigned char tlsdesc_plt_entry[plt_entry_size];
4540
4541   // The .eh_frame unwind information for the PLT.
4542   static const int plt_eh_frame_fde_size = 32;
4543   static const unsigned char plt_eh_frame_fde[plt_eh_frame_fde_size];
4544 };
4545
4546 template<int size>
4547 class Target_x86_64_nacl : public Target_x86_64<size>
4548 {
4549  public:
4550   Target_x86_64_nacl()
4551     : Target_x86_64<size>(&x86_64_nacl_info)
4552   { }
4553
4554   virtual Output_data_plt_x86_64<size>*
4555   do_make_data_plt(Layout* layout,
4556                    Output_data_got<64, false>* got,
4557                    Output_data_space* got_plt,
4558                    Output_data_space* got_irelative)
4559   {
4560     return new Output_data_plt_x86_64_nacl<size>(layout, got, got_plt,
4561                                                  got_irelative);
4562   }
4563
4564   virtual Output_data_plt_x86_64<size>*
4565   do_make_data_plt(Layout* layout,
4566                    Output_data_got<64, false>* got,
4567                    Output_data_space* got_plt,
4568                    Output_data_space* got_irelative,
4569                    unsigned int plt_count)
4570   {
4571     return new Output_data_plt_x86_64_nacl<size>(layout, got, got_plt,
4572                                                  got_irelative,
4573                                                  plt_count);
4574   }
4575
4576   virtual std::string
4577   do_code_fill(section_size_type length) const;
4578
4579  private:
4580   static const Target::Target_info x86_64_nacl_info;
4581 };
4582
4583 template<>
4584 const Target::Target_info Target_x86_64_nacl<64>::x86_64_nacl_info =
4585 {
4586   64,                   // size
4587   false,                // is_big_endian
4588   elfcpp::EM_X86_64,    // machine_code
4589   false,                // has_make_symbol
4590   false,                // has_resolve
4591   true,                 // has_code_fill
4592   true,                 // is_default_stack_executable
4593   true,                 // can_icf_inline_merge_sections
4594   '\0',                 // wrap_char
4595   "/lib64/ld-nacl-x86-64.so.1", // dynamic_linker
4596   0x20000,              // default_text_segment_address
4597   0x10000,              // abi_pagesize (overridable by -z max-page-size)
4598   0x10000,              // common_pagesize (overridable by -z common-page-size)
4599   true,                 // isolate_execinstr
4600   0x10000000,           // rosegment_gap
4601   elfcpp::SHN_UNDEF,    // small_common_shndx
4602   elfcpp::SHN_X86_64_LCOMMON,   // large_common_shndx
4603   0,                    // small_common_section_flags
4604   elfcpp::SHF_X86_64_LARGE,     // large_common_section_flags
4605   NULL,                 // attributes_section
4606   NULL,                 // attributes_vendor
4607   "_start"              // entry_symbol_name
4608 };
4609
4610 template<>
4611 const Target::Target_info Target_x86_64_nacl<32>::x86_64_nacl_info =
4612 {
4613   32,                   // size
4614   false,                // is_big_endian
4615   elfcpp::EM_X86_64,    // machine_code
4616   false,                // has_make_symbol
4617   false,                // has_resolve
4618   true,                 // has_code_fill
4619   true,                 // is_default_stack_executable
4620   true,                 // can_icf_inline_merge_sections
4621   '\0',                 // wrap_char
4622   "/lib/ld-nacl-x86-64.so.1", // dynamic_linker
4623   0x20000,              // default_text_segment_address
4624   0x10000,              // abi_pagesize (overridable by -z max-page-size)
4625   0x10000,              // common_pagesize (overridable by -z common-page-size)
4626   true,                 // isolate_execinstr
4627   0x10000000,           // rosegment_gap
4628   elfcpp::SHN_UNDEF,    // small_common_shndx
4629   elfcpp::SHN_X86_64_LCOMMON,   // large_common_shndx
4630   0,                    // small_common_section_flags
4631   elfcpp::SHF_X86_64_LARGE,     // large_common_section_flags
4632   NULL,                 // attributes_section
4633   NULL,                 // attributes_vendor
4634   "_start"              // entry_symbol_name
4635 };
4636
4637 #define NACLMASK        0xe0            // 32-byte alignment mask.
4638
4639 // The first entry in the PLT.
4640
4641 template<int size>
4642 const unsigned char
4643 Output_data_plt_x86_64_nacl<size>::first_plt_entry[plt_entry_size] =
4644 {
4645   0xff, 0x35,                         // pushq contents of memory address
4646   0, 0, 0, 0,                         // replaced with address of .got + 8
4647   0x4c, 0x8b, 0x1d,                   // mov GOT+16(%rip), %r11
4648   0, 0, 0, 0,                         // replaced with address of .got + 16
4649   0x41, 0x83, 0xe3, NACLMASK,         // and $-32, %r11d
4650   0x4d, 0x01, 0xfb,                   // add %r15, %r11
4651   0x41, 0xff, 0xe3,                   // jmpq *%r11
4652
4653   // 9-byte nop sequence to pad out to the next 32-byte boundary.
4654   0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopl %cs:0x0(%rax,%rax,1)
4655
4656   // 32 bytes of nop to pad out to the standard size
4657   0x66, 0x66, 0x66, 0x66, 0x66, 0x66,    // excess data32 prefixes
4658   0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4659   0x66, 0x66, 0x66, 0x66, 0x66, 0x66,    // excess data32 prefixes
4660   0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4661   0x66,                                  // excess data32 prefix
4662   0x90                                   // nop
4663 };
4664
4665 template<int size>
4666 void
4667 Output_data_plt_x86_64_nacl<size>::do_fill_first_plt_entry(
4668     unsigned char* pov,
4669     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
4670     typename elfcpp::Elf_types<size>::Elf_Addr plt_address)
4671 {
4672   memcpy(pov, first_plt_entry, plt_entry_size);
4673   elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
4674                                               (got_address + 8
4675                                                - (plt_address + 2 + 4)));
4676   elfcpp::Swap_unaligned<32, false>::writeval(pov + 9,
4677                                               (got_address + 16
4678                                                - (plt_address + 9 + 4)));
4679 }
4680
4681 // Subsequent entries in the PLT.
4682
4683 template<int size>
4684 const unsigned char
4685 Output_data_plt_x86_64_nacl<size>::plt_entry[plt_entry_size] =
4686 {
4687   0x4c, 0x8b, 0x1d,              // mov name@GOTPCREL(%rip),%r11
4688   0, 0, 0, 0,                    // replaced with address of symbol in .got
4689   0x41, 0x83, 0xe3, NACLMASK,    // and $-32, %r11d
4690   0x4d, 0x01, 0xfb,              // add %r15, %r11
4691   0x41, 0xff, 0xe3,              // jmpq *%r11
4692
4693   // 15-byte nop sequence to pad out to the next 32-byte boundary.
4694   0x66, 0x66, 0x66, 0x66, 0x66, 0x66,    // excess data32 prefixes
4695   0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4696
4697   // Lazy GOT entries point here (32-byte aligned).
4698   0x68,                       // pushq immediate
4699   0, 0, 0, 0,                 // replaced with index into relocation table
4700   0xe9,                       // jmp relative
4701   0, 0, 0, 0,                 // replaced with offset to start of .plt0
4702
4703   // 22 bytes of nop to pad out to the standard size.
4704   0x66, 0x66, 0x66, 0x66, 0x66, 0x66,    // excess data32 prefixes
4705   0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4706   0x0f, 0x1f, 0x80, 0, 0, 0, 0,          // nopl 0x0(%rax)
4707 };
4708
4709 template<int size>
4710 unsigned int
4711 Output_data_plt_x86_64_nacl<size>::do_fill_plt_entry(
4712     unsigned char* pov,
4713     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
4714     typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
4715     unsigned int got_offset,
4716     unsigned int plt_offset,
4717     unsigned int plt_index)
4718 {
4719   memcpy(pov, plt_entry, plt_entry_size);
4720   elfcpp::Swap_unaligned<32, false>::writeval(pov + 3,
4721                                               (got_address + got_offset
4722                                                - (plt_address + plt_offset
4723                                                   + 3 + 4)));
4724
4725   elfcpp::Swap_unaligned<32, false>::writeval(pov + 33, plt_index);
4726   elfcpp::Swap_unaligned<32, false>::writeval(pov + 38,
4727                                               - (plt_offset + 38 + 4));
4728
4729   return 32;
4730 }
4731
4732 // The reserved TLSDESC entry in the PLT.
4733
4734 template<int size>
4735 const unsigned char
4736 Output_data_plt_x86_64_nacl<size>::tlsdesc_plt_entry[plt_entry_size] =
4737 {
4738   0xff, 0x35,                   // pushq x(%rip)
4739   0, 0, 0, 0,   // replaced with address of linkmap GOT entry (at PLTGOT + 8)
4740   0x4c, 0x8b, 0x1d,             // mov y(%rip),%r11
4741   0, 0, 0, 0,   // replaced with offset of reserved TLSDESC_GOT entry
4742   0x41, 0x83, 0xe3, NACLMASK,   // and $-32, %r11d
4743   0x4d, 0x01, 0xfb,             // add %r15, %r11
4744   0x41, 0xff, 0xe3,             // jmpq *%r11
4745
4746   // 41 bytes of nop to pad out to the standard size.
4747   0x66, 0x66, 0x66, 0x66, 0x66, 0x66,    // excess data32 prefixes
4748   0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4749   0x66, 0x66, 0x66, 0x66, 0x66, 0x66,    // excess data32 prefixes
4750   0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4751   0x66, 0x66,                            // excess data32 prefixes
4752   0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4753 };
4754
4755 template<int size>
4756 void
4757 Output_data_plt_x86_64_nacl<size>::do_fill_tlsdesc_entry(
4758     unsigned char* pov,
4759     typename elfcpp::Elf_types<size>::Elf_Addr got_address,
4760     typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
4761     typename elfcpp::Elf_types<size>::Elf_Addr got_base,
4762     unsigned int tlsdesc_got_offset,
4763     unsigned int plt_offset)
4764 {
4765   memcpy(pov, tlsdesc_plt_entry, plt_entry_size);
4766   elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
4767                                               (got_address + 8
4768                                                - (plt_address + plt_offset
4769                                                   + 2 + 4)));
4770   elfcpp::Swap_unaligned<32, false>::writeval(pov + 9,
4771                                               (got_base
4772                                                + tlsdesc_got_offset
4773                                                - (plt_address + plt_offset
4774                                                   + 9 + 4)));
4775 }
4776
4777 // The .eh_frame unwind information for the PLT.
4778
4779 template<int size>
4780 const unsigned char
4781 Output_data_plt_x86_64_nacl<size>::plt_eh_frame_fde[plt_eh_frame_fde_size] =
4782 {
4783   0, 0, 0, 0,                           // Replaced with offset to .plt.
4784   0, 0, 0, 0,                           // Replaced with size of .plt.
4785   0,                                    // Augmentation size.
4786   elfcpp::DW_CFA_def_cfa_offset, 16,    // DW_CFA_def_cfa_offset: 16.
4787   elfcpp::DW_CFA_advance_loc + 6,       // Advance 6 to __PLT__ + 6.
4788   elfcpp::DW_CFA_def_cfa_offset, 24,    // DW_CFA_def_cfa_offset: 24.
4789   elfcpp::DW_CFA_advance_loc + 58,      // Advance 58 to __PLT__ + 64.
4790   elfcpp::DW_CFA_def_cfa_expression,    // DW_CFA_def_cfa_expression.
4791   13,                                   // Block length.
4792   elfcpp::DW_OP_breg7, 8,               // Push %rsp + 8.
4793   elfcpp::DW_OP_breg16, 0,              // Push %rip.
4794   elfcpp::DW_OP_const1u, 63,            // Push 0x3f.
4795   elfcpp::DW_OP_and,                    // & (%rip & 0x3f).
4796   elfcpp::DW_OP_const1u, 37,            // Push 0x25.
4797   elfcpp::DW_OP_ge,                     // >= ((%rip & 0x3f) >= 0x25)
4798   elfcpp::DW_OP_lit3,                   // Push 3.
4799   elfcpp::DW_OP_shl,                    // << (((%rip & 0x3f) >= 0x25) << 3)
4800   elfcpp::DW_OP_plus,                   // + ((((%rip&0x3f)>=0x25)<<3)+%rsp+8
4801   elfcpp::DW_CFA_nop,                   // Align to 32 bytes.
4802   elfcpp::DW_CFA_nop
4803 };
4804
4805 // Return a string used to fill a code section with nops.
4806 // For NaCl, long NOPs are only valid if they do not cross
4807 // bundle alignment boundaries, so keep it simple with one-byte NOPs.
4808 template<int size>
4809 std::string
4810 Target_x86_64_nacl<size>::do_code_fill(section_size_type length) const
4811 {
4812   return std::string(length, static_cast<char>(0x90));
4813 }
4814
4815 // The selector for x86_64-nacl object files.
4816
4817 template<int size>
4818 class Target_selector_x86_64_nacl
4819   : public Target_selector_nacl<Target_selector_x86_64<size>,
4820                                 Target_x86_64_nacl<size> >
4821 {
4822  public:
4823   Target_selector_x86_64_nacl()
4824     : Target_selector_nacl<Target_selector_x86_64<size>,
4825                            Target_x86_64_nacl<size> >("x86-64",
4826                                                       size == 64
4827                                                       ? "elf64-x86-64-nacl"
4828                                                       : "elf32-x86-64-nacl",
4829                                                       size == 64
4830                                                       ? "elf_x86_64_nacl"
4831                                                       : "elf32_x86_64_nacl")
4832   { }
4833 };
4834
4835 Target_selector_x86_64_nacl<64> target_selector_x86_64;
4836 Target_selector_x86_64_nacl<32> target_selector_x32;
4837
4838 } // End anonymous namespace.