* arm.cc (Target_arm<big_endian>::gc_process_relocs): Add template
[external/binutils.git] / gold / i386.cc
1 // i386.cc -- i386 target support for gold.
2
3 // Copyright 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
4 // Written by Ian Lance Taylor <iant@google.com>.
5
6 // This file is part of gold.
7
8 // This program is free software; you can redistribute it and/or modify
9 // it under the terms of the GNU General Public License as published by
10 // the Free Software Foundation; either version 3 of the License, or
11 // (at your option) any later version.
12
13 // This program is distributed in the hope that it will be useful,
14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16 // GNU General Public License for more details.
17
18 // You should have received a copy of the GNU General Public License
19 // along with this program; if not, write to the Free Software
20 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
21 // MA 02110-1301, USA.
22
23 #include "gold.h"
24
25 #include <cstring>
26
27 #include "elfcpp.h"
28 #include "parameters.h"
29 #include "reloc.h"
30 #include "i386.h"
31 #include "object.h"
32 #include "symtab.h"
33 #include "layout.h"
34 #include "output.h"
35 #include "copy-relocs.h"
36 #include "target.h"
37 #include "target-reloc.h"
38 #include "target-select.h"
39 #include "tls.h"
40 #include "freebsd.h"
41 #include "gc.h"
42
43 namespace
44 {
45
46 using namespace gold;
47
48 class Output_data_plt_i386;
49
50 // The i386 target class.
51 // TLS info comes from
52 //   http://people.redhat.com/drepper/tls.pdf
53 //   http://www.lsd.ic.unicamp.br/~oliva/writeups/TLS/RFC-TLSDESC-x86.txt
54
55 class Target_i386 : public Target_freebsd<32, false>
56 {
57  public:
58   typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, false> Reloc_section;
59
60   Target_i386()
61     : Target_freebsd<32, false>(&i386_info),
62       got_(NULL), plt_(NULL), got_plt_(NULL), global_offset_table_(NULL),
63       rel_dyn_(NULL), copy_relocs_(elfcpp::R_386_COPY), dynbss_(NULL),
64       got_mod_index_offset_(-1U), tls_base_symbol_defined_(false)
65   { }
66
67   inline bool
68   can_check_for_function_pointers() const
69   { return true; }
70
71   // Process the relocations to determine unreferenced sections for 
72   // garbage collection.
73   void
74   gc_process_relocs(Symbol_table* symtab,
75                     Layout* layout,
76                     Sized_relobj<32, false>* object,
77                     unsigned int data_shndx,
78                     unsigned int sh_type,
79                     const unsigned char* prelocs,
80                     size_t reloc_count,
81                     Output_section* output_section,
82                     bool needs_special_offset_handling,
83                     size_t local_symbol_count,
84                     const unsigned char* plocal_symbols);
85
86   // Scan the relocations to look for symbol adjustments.
87   void
88   scan_relocs(Symbol_table* symtab,
89               Layout* layout,
90               Sized_relobj<32, false>* object,
91               unsigned int data_shndx,
92               unsigned int sh_type,
93               const unsigned char* prelocs,
94               size_t reloc_count,
95               Output_section* output_section,
96               bool needs_special_offset_handling,
97               size_t local_symbol_count,
98               const unsigned char* plocal_symbols);
99
100   // Finalize the sections.
101   void
102   do_finalize_sections(Layout*, const Input_objects*, Symbol_table*);
103
104   // Return the value to use for a dynamic which requires special
105   // treatment.
106   uint64_t
107   do_dynsym_value(const Symbol*) const;
108
109   // Relocate a section.
110   void
111   relocate_section(const Relocate_info<32, false>*,
112                    unsigned int sh_type,
113                    const unsigned char* prelocs,
114                    size_t reloc_count,
115                    Output_section* output_section,
116                    bool needs_special_offset_handling,
117                    unsigned char* view,
118                    elfcpp::Elf_types<32>::Elf_Addr view_address,
119                    section_size_type view_size,
120                    const Reloc_symbol_changes*);
121
122   // Scan the relocs during a relocatable link.
123   void
124   scan_relocatable_relocs(Symbol_table* symtab,
125                           Layout* layout,
126                           Sized_relobj<32, false>* object,
127                           unsigned int data_shndx,
128                           unsigned int sh_type,
129                           const unsigned char* prelocs,
130                           size_t reloc_count,
131                           Output_section* output_section,
132                           bool needs_special_offset_handling,
133                           size_t local_symbol_count,
134                           const unsigned char* plocal_symbols,
135                           Relocatable_relocs*);
136
137   // Relocate a section during a relocatable link.
138   void
139   relocate_for_relocatable(const Relocate_info<32, false>*,
140                            unsigned int sh_type,
141                            const unsigned char* prelocs,
142                            size_t reloc_count,
143                            Output_section* output_section,
144                            off_t offset_in_output_section,
145                            const Relocatable_relocs*,
146                            unsigned char* view,
147                            elfcpp::Elf_types<32>::Elf_Addr view_address,
148                            section_size_type view_size,
149                            unsigned char* reloc_view,
150                            section_size_type reloc_view_size);
151
152   // Return a string used to fill a code section with nops.
153   std::string
154   do_code_fill(section_size_type length) const;
155
156   // Return whether SYM is defined by the ABI.
157   bool
158   do_is_defined_by_abi(const Symbol* sym) const
159   { return strcmp(sym->name(), "___tls_get_addr") == 0; }
160
161   // Return whether a symbol name implies a local label.  The UnixWare
162   // 2.1 cc generates temporary symbols that start with .X, so we
163   // recognize them here.  FIXME: do other SVR4 compilers also use .X?.
164   // If so, we should move the .X recognition into
165   // Target::do_is_local_label_name.
166   bool
167   do_is_local_label_name(const char* name) const
168   {
169     if (name[0] == '.' && name[1] == 'X')
170       return true;
171     return Target::do_is_local_label_name(name);
172   }
173
174   // Return whether SYM is call to a non-split function.
175   bool
176   do_is_call_to_non_split(const Symbol* sym, unsigned int) const;
177
178   // Adjust -fstack-split code which calls non-stack-split code.
179   void
180   do_calls_non_split(Relobj* object, unsigned int shndx,
181                      section_offset_type fnoffset, section_size_type fnsize,
182                      unsigned char* view, section_size_type view_size,
183                      std::string* from, std::string* to) const;
184
185   // Return the size of the GOT section.
186   section_size_type
187   got_size()
188   {
189     gold_assert(this->got_ != NULL);
190     return this->got_->data_size();
191   }
192
193  private:
194   // The class which scans relocations.
195   struct Scan
196   {
197     inline void
198     local(Symbol_table* symtab, Layout* layout, Target_i386* target,
199           Sized_relobj<32, false>* object,
200           unsigned int data_shndx,
201           Output_section* output_section,
202           const elfcpp::Rel<32, false>& reloc, unsigned int r_type,
203           const elfcpp::Sym<32, false>& lsym);
204
205     inline void
206     global(Symbol_table* symtab, Layout* layout, Target_i386* target,
207            Sized_relobj<32, false>* object,
208            unsigned int data_shndx,
209            Output_section* output_section,
210            const elfcpp::Rel<32, false>& reloc, unsigned int r_type,
211            Symbol* gsym);
212
213     inline bool
214     local_reloc_may_be_function_pointer(Symbol_table* symtab, Layout* layout,
215                                         Target_i386* target,
216                                         Sized_relobj<32, false>* object,
217                                         unsigned int data_shndx,
218                                         Output_section* output_section,
219                                         const elfcpp::Rel<32, false>& reloc,
220                                         unsigned int r_type,
221                                         const elfcpp::Sym<32, false>& lsym);
222
223     inline bool
224     global_reloc_may_be_function_pointer(Symbol_table* symtab, Layout* layout,
225                                          Target_i386* target,
226                                          Sized_relobj<32, false>* object,
227                                          unsigned int data_shndx,
228                                          Output_section* output_section,
229                                          const elfcpp::Rel<32, false>& reloc,
230                                          unsigned int r_type,
231                                          Symbol* gsym);
232
233     inline bool
234     possible_function_pointer_reloc(unsigned int r_type);
235
236     static void
237     unsupported_reloc_local(Sized_relobj<32, false>*, unsigned int r_type);
238
239     static void
240     unsupported_reloc_global(Sized_relobj<32, false>*, unsigned int r_type,
241                              Symbol*);
242   };
243
244   // The class which implements relocation.
245   class Relocate
246   {
247    public:
248     Relocate()
249       : skip_call_tls_get_addr_(false),
250         local_dynamic_type_(LOCAL_DYNAMIC_NONE)
251     { }
252
253     ~Relocate()
254     {
255       if (this->skip_call_tls_get_addr_)
256         {
257           // FIXME: This needs to specify the location somehow.
258           gold_error(_("missing expected TLS relocation"));
259         }
260     }
261
262     // Return whether the static relocation needs to be applied.
263     inline bool
264     should_apply_static_reloc(const Sized_symbol<32>* gsym,
265                               int ref_flags,
266                               bool is_32bit,
267                               Output_section* output_section);
268
269     // Do a relocation.  Return false if the caller should not issue
270     // any warnings about this relocation.
271     inline bool
272     relocate(const Relocate_info<32, false>*, Target_i386*, Output_section*,
273              size_t relnum, const elfcpp::Rel<32, false>&,
274              unsigned int r_type, const Sized_symbol<32>*,
275              const Symbol_value<32>*,
276              unsigned char*, elfcpp::Elf_types<32>::Elf_Addr,
277              section_size_type);
278
279    private:
280     // Do a TLS relocation.
281     inline void
282     relocate_tls(const Relocate_info<32, false>*, Target_i386* target,
283                  size_t relnum, const elfcpp::Rel<32, false>&,
284                  unsigned int r_type, const Sized_symbol<32>*,
285                  const Symbol_value<32>*,
286                  unsigned char*, elfcpp::Elf_types<32>::Elf_Addr,
287                  section_size_type);
288
289     // Do a TLS General-Dynamic to Initial-Exec transition.
290     inline void
291     tls_gd_to_ie(const Relocate_info<32, false>*, size_t relnum,
292                  Output_segment* tls_segment,
293                  const elfcpp::Rel<32, false>&, unsigned int r_type,
294                  elfcpp::Elf_types<32>::Elf_Addr value,
295                  unsigned char* view,
296                  section_size_type view_size);
297
298     // Do a TLS General-Dynamic to Local-Exec transition.
299     inline void
300     tls_gd_to_le(const Relocate_info<32, false>*, size_t relnum,
301                  Output_segment* tls_segment,
302                  const elfcpp::Rel<32, false>&, unsigned int r_type,
303                  elfcpp::Elf_types<32>::Elf_Addr value,
304                  unsigned char* view,
305                  section_size_type view_size);
306
307     // Do a TLS_GOTDESC or TLS_DESC_CALL General-Dynamic to Initial-Exec
308     // transition.
309     inline void
310     tls_desc_gd_to_ie(const Relocate_info<32, false>*, size_t relnum,
311                       Output_segment* tls_segment,
312                       const elfcpp::Rel<32, false>&, unsigned int r_type,
313                       elfcpp::Elf_types<32>::Elf_Addr value,
314                       unsigned char* view,
315                       section_size_type view_size);
316
317     // Do a TLS_GOTDESC or TLS_DESC_CALL General-Dynamic to Local-Exec
318     // transition.
319     inline void
320     tls_desc_gd_to_le(const Relocate_info<32, false>*, size_t relnum,
321                       Output_segment* tls_segment,
322                       const elfcpp::Rel<32, false>&, unsigned int r_type,
323                       elfcpp::Elf_types<32>::Elf_Addr value,
324                       unsigned char* view,
325                       section_size_type view_size);
326
327     // Do a TLS Local-Dynamic to Local-Exec transition.
328     inline void
329     tls_ld_to_le(const Relocate_info<32, false>*, size_t relnum,
330                  Output_segment* tls_segment,
331                  const elfcpp::Rel<32, false>&, unsigned int r_type,
332                  elfcpp::Elf_types<32>::Elf_Addr value,
333                  unsigned char* view,
334                  section_size_type view_size);
335
336     // Do a TLS Initial-Exec to Local-Exec transition.
337     static inline void
338     tls_ie_to_le(const Relocate_info<32, false>*, size_t relnum,
339                  Output_segment* tls_segment,
340                  const elfcpp::Rel<32, false>&, unsigned int r_type,
341                  elfcpp::Elf_types<32>::Elf_Addr value,
342                  unsigned char* view,
343                  section_size_type view_size);
344
345     // We need to keep track of which type of local dynamic relocation
346     // we have seen, so that we can optimize R_386_TLS_LDO_32 correctly.
347     enum Local_dynamic_type
348     {
349       LOCAL_DYNAMIC_NONE,
350       LOCAL_DYNAMIC_SUN,
351       LOCAL_DYNAMIC_GNU
352     };
353
354     // This is set if we should skip the next reloc, which should be a
355     // PLT32 reloc against ___tls_get_addr.
356     bool skip_call_tls_get_addr_;
357     // The type of local dynamic relocation we have seen in the section
358     // being relocated, if any.
359     Local_dynamic_type local_dynamic_type_;
360   };
361
362   // A class which returns the size required for a relocation type,
363   // used while scanning relocs during a relocatable link.
364   class Relocatable_size_for_reloc
365   {
366    public:
367     unsigned int
368     get_size_for_reloc(unsigned int, Relobj*);
369   };
370
371   // Adjust TLS relocation type based on the options and whether this
372   // is a local symbol.
373   static tls::Tls_optimization
374   optimize_tls_reloc(bool is_final, int r_type);
375
376   // Get the GOT section, creating it if necessary.
377   Output_data_got<32, false>*
378   got_section(Symbol_table*, Layout*);
379
380   // Get the GOT PLT section.
381   Output_data_space*
382   got_plt_section() const
383   {
384     gold_assert(this->got_plt_ != NULL);
385     return this->got_plt_;
386   }
387
388   // Create a PLT entry for a global symbol.
389   void
390   make_plt_entry(Symbol_table*, Layout*, Symbol*);
391
392   // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
393   void
394   define_tls_base_symbol(Symbol_table*, Layout*);
395
396   // Create a GOT entry for the TLS module index.
397   unsigned int
398   got_mod_index_entry(Symbol_table* symtab, Layout* layout,
399                       Sized_relobj<32, false>* object);
400
401   // Get the PLT section.
402   Output_data_plt_i386*
403   plt_section() const
404   {
405     gold_assert(this->plt_ != NULL);
406     return this->plt_;
407   }
408
409   // Get the dynamic reloc section, creating it if necessary.
410   Reloc_section*
411   rel_dyn_section(Layout*);
412
413   // Get the section to use for TLS_DESC relocations.
414   Reloc_section*
415   rel_tls_desc_section(Layout*) const;
416
417   // Add a potential copy relocation.
418   void
419   copy_reloc(Symbol_table* symtab, Layout* layout,
420              Sized_relobj<32, false>* object,
421              unsigned int shndx, Output_section* output_section,
422              Symbol* sym, const elfcpp::Rel<32, false>& reloc)
423   {
424     this->copy_relocs_.copy_reloc(symtab, layout,
425                                   symtab->get_sized_symbol<32>(sym),
426                                   object, shndx, output_section, reloc,
427                                   this->rel_dyn_section(layout));
428   }
429
430   // Information about this specific target which we pass to the
431   // general Target structure.
432   static const Target::Target_info i386_info;
433
434   // The types of GOT entries needed for this platform.
435   enum Got_type
436   {
437     GOT_TYPE_STANDARD = 0,      // GOT entry for a regular symbol
438     GOT_TYPE_TLS_NOFFSET = 1,   // GOT entry for negative TLS offset
439     GOT_TYPE_TLS_OFFSET = 2,    // GOT entry for positive TLS offset
440     GOT_TYPE_TLS_PAIR = 3,      // GOT entry for TLS module/offset pair
441     GOT_TYPE_TLS_DESC = 4       // GOT entry for TLS_DESC pair
442   };
443
444   // The GOT section.
445   Output_data_got<32, false>* got_;
446   // The PLT section.
447   Output_data_plt_i386* plt_;
448   // The GOT PLT section.
449   Output_data_space* got_plt_;
450   // The _GLOBAL_OFFSET_TABLE_ symbol.
451   Symbol* global_offset_table_;
452   // The dynamic reloc section.
453   Reloc_section* rel_dyn_;
454   // Relocs saved to avoid a COPY reloc.
455   Copy_relocs<elfcpp::SHT_REL, 32, false> copy_relocs_;
456   // Space for variables copied with a COPY reloc.
457   Output_data_space* dynbss_;
458   // Offset of the GOT entry for the TLS module index.
459   unsigned int got_mod_index_offset_;
460   // True if the _TLS_MODULE_BASE_ symbol has been defined.
461   bool tls_base_symbol_defined_;
462 };
463
464 const Target::Target_info Target_i386::i386_info =
465 {
466   32,                   // size
467   false,                // is_big_endian
468   elfcpp::EM_386,       // machine_code
469   false,                // has_make_symbol
470   false,                // has_resolve
471   true,                 // has_code_fill
472   true,                 // is_default_stack_executable
473   '\0',                 // wrap_char
474   "/usr/lib/libc.so.1", // dynamic_linker
475   0x08048000,           // default_text_segment_address
476   0x1000,               // abi_pagesize (overridable by -z max-page-size)
477   0x1000,               // common_pagesize (overridable by -z common-page-size)
478   elfcpp::SHN_UNDEF,    // small_common_shndx
479   elfcpp::SHN_UNDEF,    // large_common_shndx
480   0,                    // small_common_section_flags
481   0,                    // large_common_section_flags
482   NULL,                 // attributes_section
483   NULL                  // attributes_vendor
484 };
485
486 // Get the GOT section, creating it if necessary.
487
488 Output_data_got<32, false>*
489 Target_i386::got_section(Symbol_table* symtab, Layout* layout)
490 {
491   if (this->got_ == NULL)
492     {
493       gold_assert(symtab != NULL && layout != NULL);
494
495       this->got_ = new Output_data_got<32, false>();
496
497       layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
498                                       (elfcpp::SHF_ALLOC
499                                        | elfcpp::SHF_WRITE),
500                                       this->got_, false, true, true, false);
501
502       this->got_plt_ = new Output_data_space(4, "** GOT PLT");
503       layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
504                                       (elfcpp::SHF_ALLOC
505                                        | elfcpp::SHF_WRITE),
506                                       this->got_plt_, false, false, false,
507                                       true);
508
509       // The first three entries are reserved.
510       this->got_plt_->set_current_data_size(3 * 4);
511
512       // Those bytes can go into the relro segment.
513       layout->increase_relro(3 * 4);
514
515       // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
516       this->global_offset_table_ =
517         symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
518                                       Symbol_table::PREDEFINED,
519                                       this->got_plt_,
520                                       0, 0, elfcpp::STT_OBJECT,
521                                       elfcpp::STB_LOCAL,
522                                       elfcpp::STV_HIDDEN, 0,
523                                       false, false);
524     }
525
526   return this->got_;
527 }
528
529 // Get the dynamic reloc section, creating it if necessary.
530
531 Target_i386::Reloc_section*
532 Target_i386::rel_dyn_section(Layout* layout)
533 {
534   if (this->rel_dyn_ == NULL)
535     {
536       gold_assert(layout != NULL);
537       this->rel_dyn_ = new Reloc_section(parameters->options().combreloc());
538       layout->add_output_section_data(".rel.dyn", elfcpp::SHT_REL,
539                                       elfcpp::SHF_ALLOC, this->rel_dyn_, true,
540                                       false, false, false);
541     }
542   return this->rel_dyn_;
543 }
544
545 // A class to handle the PLT data.
546
547 class Output_data_plt_i386 : public Output_section_data
548 {
549  public:
550   typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, false> Reloc_section;
551
552   Output_data_plt_i386(Layout*, Output_data_space*);
553
554   // Add an entry to the PLT.
555   void
556   add_entry(Symbol* gsym);
557
558   // Return the .rel.plt section data.
559   const Reloc_section*
560   rel_plt() const
561   { return this->rel_; }
562
563   // Return where the TLS_DESC relocations should go.
564   Reloc_section*
565   rel_tls_desc(Layout*);
566
567  protected:
568   void
569   do_adjust_output_section(Output_section* os);
570
571   // Write to a map file.
572   void
573   do_print_to_mapfile(Mapfile* mapfile) const
574   { mapfile->print_output_data(this, _("** PLT")); }
575
576  private:
577   // The size of an entry in the PLT.
578   static const int plt_entry_size = 16;
579
580   // The first entry in the PLT for an executable.
581   static unsigned char exec_first_plt_entry[plt_entry_size];
582
583   // The first entry in the PLT for a shared object.
584   static unsigned char dyn_first_plt_entry[plt_entry_size];
585
586   // Other entries in the PLT for an executable.
587   static unsigned char exec_plt_entry[plt_entry_size];
588
589   // Other entries in the PLT for a shared object.
590   static unsigned char dyn_plt_entry[plt_entry_size];
591
592   // Set the final size.
593   void
594   set_final_data_size()
595   { this->set_data_size((this->count_ + 1) * plt_entry_size); }
596
597   // Write out the PLT data.
598   void
599   do_write(Output_file*);
600
601   // The reloc section.
602   Reloc_section* rel_;
603   // The TLS_DESC relocations, if necessary.  These must follow the
604   // regular PLT relocs.
605   Reloc_section* tls_desc_rel_;
606   // The .got.plt section.
607   Output_data_space* got_plt_;
608   // The number of PLT entries.
609   unsigned int count_;
610 };
611
612 // Create the PLT section.  The ordinary .got section is an argument,
613 // since we need to refer to the start.  We also create our own .got
614 // section just for PLT entries.
615
616 Output_data_plt_i386::Output_data_plt_i386(Layout* layout,
617                                            Output_data_space* got_plt)
618   : Output_section_data(4), tls_desc_rel_(NULL), got_plt_(got_plt), count_(0)
619 {
620   this->rel_ = new Reloc_section(false);
621   layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL,
622                                   elfcpp::SHF_ALLOC, this->rel_, true,
623                                   false, false, false);
624 }
625
626 void
627 Output_data_plt_i386::do_adjust_output_section(Output_section* os)
628 {
629   // UnixWare sets the entsize of .plt to 4, and so does the old GNU
630   // linker, and so do we.
631   os->set_entsize(4);
632 }
633
634 // Add an entry to the PLT.
635
636 void
637 Output_data_plt_i386::add_entry(Symbol* gsym)
638 {
639   gold_assert(!gsym->has_plt_offset());
640
641   // Note that when setting the PLT offset we skip the initial
642   // reserved PLT entry.
643   gsym->set_plt_offset((this->count_ + 1) * plt_entry_size);
644
645   ++this->count_;
646
647   section_offset_type got_offset = this->got_plt_->current_data_size();
648
649   // Every PLT entry needs a GOT entry which points back to the PLT
650   // entry (this will be changed by the dynamic linker, normally
651   // lazily when the function is called).
652   this->got_plt_->set_current_data_size(got_offset + 4);
653
654   // Every PLT entry needs a reloc.
655   gsym->set_needs_dynsym_entry();
656   this->rel_->add_global(gsym, elfcpp::R_386_JUMP_SLOT, this->got_plt_,
657                          got_offset);
658
659   // Note that we don't need to save the symbol.  The contents of the
660   // PLT are independent of which symbols are used.  The symbols only
661   // appear in the relocations.
662 }
663
664 // Return where the TLS_DESC relocations should go, creating it if
665 // necessary. These follow the JUMP_SLOT relocations.
666
667 Output_data_plt_i386::Reloc_section*
668 Output_data_plt_i386::rel_tls_desc(Layout* layout)
669 {
670   if (this->tls_desc_rel_ == NULL)
671     {
672       this->tls_desc_rel_ = new Reloc_section(false);
673       layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL,
674                                       elfcpp::SHF_ALLOC, this->tls_desc_rel_,
675                                       true, false, false, false);
676       gold_assert(this->tls_desc_rel_->output_section() ==
677                   this->rel_->output_section());
678     }
679   return this->tls_desc_rel_;
680 }
681
682 // The first entry in the PLT for an executable.
683
684 unsigned char Output_data_plt_i386::exec_first_plt_entry[plt_entry_size] =
685 {
686   0xff, 0x35,   // pushl contents of memory address
687   0, 0, 0, 0,   // replaced with address of .got + 4
688   0xff, 0x25,   // jmp indirect
689   0, 0, 0, 0,   // replaced with address of .got + 8
690   0, 0, 0, 0    // unused
691 };
692
693 // The first entry in the PLT for a shared object.
694
695 unsigned char Output_data_plt_i386::dyn_first_plt_entry[plt_entry_size] =
696 {
697   0xff, 0xb3, 4, 0, 0, 0,       // pushl 4(%ebx)
698   0xff, 0xa3, 8, 0, 0, 0,       // jmp *8(%ebx)
699   0, 0, 0, 0                    // unused
700 };
701
702 // Subsequent entries in the PLT for an executable.
703
704 unsigned char Output_data_plt_i386::exec_plt_entry[plt_entry_size] =
705 {
706   0xff, 0x25,   // jmp indirect
707   0, 0, 0, 0,   // replaced with address of symbol in .got
708   0x68,         // pushl immediate
709   0, 0, 0, 0,   // replaced with offset into relocation table
710   0xe9,         // jmp relative
711   0, 0, 0, 0    // replaced with offset to start of .plt
712 };
713
714 // Subsequent entries in the PLT for a shared object.
715
716 unsigned char Output_data_plt_i386::dyn_plt_entry[plt_entry_size] =
717 {
718   0xff, 0xa3,   // jmp *offset(%ebx)
719   0, 0, 0, 0,   // replaced with offset of symbol in .got
720   0x68,         // pushl immediate
721   0, 0, 0, 0,   // replaced with offset into relocation table
722   0xe9,         // jmp relative
723   0, 0, 0, 0    // replaced with offset to start of .plt
724 };
725
726 // Write out the PLT.  This uses the hand-coded instructions above,
727 // and adjusts them as needed.  This is all specified by the i386 ELF
728 // Processor Supplement.
729
730 void
731 Output_data_plt_i386::do_write(Output_file* of)
732 {
733   const off_t offset = this->offset();
734   const section_size_type oview_size =
735     convert_to_section_size_type(this->data_size());
736   unsigned char* const oview = of->get_output_view(offset, oview_size);
737
738   const off_t got_file_offset = this->got_plt_->offset();
739   const section_size_type got_size =
740     convert_to_section_size_type(this->got_plt_->data_size());
741   unsigned char* const got_view = of->get_output_view(got_file_offset,
742                                                       got_size);
743
744   unsigned char* pov = oview;
745
746   elfcpp::Elf_types<32>::Elf_Addr plt_address = this->address();
747   elfcpp::Elf_types<32>::Elf_Addr got_address = this->got_plt_->address();
748
749   if (parameters->options().output_is_position_independent())
750     memcpy(pov, dyn_first_plt_entry, plt_entry_size);
751   else
752     {
753       memcpy(pov, exec_first_plt_entry, plt_entry_size);
754       elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_address + 4);
755       elfcpp::Swap<32, false>::writeval(pov + 8, got_address + 8);
756     }
757   pov += plt_entry_size;
758
759   unsigned char* got_pov = got_view;
760
761   memset(got_pov, 0, 12);
762   got_pov += 12;
763
764   const int rel_size = elfcpp::Elf_sizes<32>::rel_size;
765
766   unsigned int plt_offset = plt_entry_size;
767   unsigned int plt_rel_offset = 0;
768   unsigned int got_offset = 12;
769   const unsigned int count = this->count_;
770   for (unsigned int i = 0;
771        i < count;
772        ++i,
773          pov += plt_entry_size,
774          got_pov += 4,
775          plt_offset += plt_entry_size,
776          plt_rel_offset += rel_size,
777          got_offset += 4)
778     {
779       // Set and adjust the PLT entry itself.
780
781       if (parameters->options().output_is_position_independent())
782         {
783           memcpy(pov, dyn_plt_entry, plt_entry_size);
784           elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_offset);
785         }
786       else
787         {
788           memcpy(pov, exec_plt_entry, plt_entry_size);
789           elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
790                                                       (got_address
791                                                        + got_offset));
792         }
793
794       elfcpp::Swap_unaligned<32, false>::writeval(pov + 7, plt_rel_offset);
795       elfcpp::Swap<32, false>::writeval(pov + 12,
796                                         - (plt_offset + plt_entry_size));
797
798       // Set the entry in the GOT.
799       elfcpp::Swap<32, false>::writeval(got_pov, plt_address + plt_offset + 6);
800     }
801
802   gold_assert(static_cast<section_size_type>(pov - oview) == oview_size);
803   gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size);
804
805   of->write_output_view(offset, oview_size, oview);
806   of->write_output_view(got_file_offset, got_size, got_view);
807 }
808
809 // Create a PLT entry for a global symbol.
810
811 void
812 Target_i386::make_plt_entry(Symbol_table* symtab, Layout* layout, Symbol* gsym)
813 {
814   if (gsym->has_plt_offset())
815     return;
816
817   if (this->plt_ == NULL)
818     {
819       // Create the GOT sections first.
820       this->got_section(symtab, layout);
821
822       this->plt_ = new Output_data_plt_i386(layout, this->got_plt_);
823       layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
824                                       (elfcpp::SHF_ALLOC
825                                        | elfcpp::SHF_EXECINSTR),
826                                       this->plt_, false, false, false, false);
827     }
828
829   this->plt_->add_entry(gsym);
830 }
831
832 // Get the section to use for TLS_DESC relocations.
833
834 Target_i386::Reloc_section*
835 Target_i386::rel_tls_desc_section(Layout* layout) const
836 {
837   return this->plt_section()->rel_tls_desc(layout);
838 }
839
840 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
841
842 void
843 Target_i386::define_tls_base_symbol(Symbol_table* symtab, Layout* layout)
844 {
845   if (this->tls_base_symbol_defined_)
846     return;
847
848   Output_segment* tls_segment = layout->tls_segment();
849   if (tls_segment != NULL)
850     {
851       bool is_exec = parameters->options().output_is_executable();
852       symtab->define_in_output_segment("_TLS_MODULE_BASE_", NULL,
853                                        Symbol_table::PREDEFINED,
854                                        tls_segment, 0, 0,
855                                        elfcpp::STT_TLS,
856                                        elfcpp::STB_LOCAL,
857                                        elfcpp::STV_HIDDEN, 0,
858                                        (is_exec
859                                         ? Symbol::SEGMENT_END
860                                         : Symbol::SEGMENT_START),
861                                        true);
862     }
863   this->tls_base_symbol_defined_ = true;
864 }
865
866 // Create a GOT entry for the TLS module index.
867
868 unsigned int
869 Target_i386::got_mod_index_entry(Symbol_table* symtab, Layout* layout,
870                                  Sized_relobj<32, false>* object)
871 {
872   if (this->got_mod_index_offset_ == -1U)
873     {
874       gold_assert(symtab != NULL && layout != NULL && object != NULL);
875       Reloc_section* rel_dyn = this->rel_dyn_section(layout);
876       Output_data_got<32, false>* got = this->got_section(symtab, layout);
877       unsigned int got_offset = got->add_constant(0);
878       rel_dyn->add_local(object, 0, elfcpp::R_386_TLS_DTPMOD32, got,
879                          got_offset);
880       got->add_constant(0);
881       this->got_mod_index_offset_ = got_offset;
882     }
883   return this->got_mod_index_offset_;
884 }
885
886 // Optimize the TLS relocation type based on what we know about the
887 // symbol.  IS_FINAL is true if the final address of this symbol is
888 // known at link time.
889
890 tls::Tls_optimization
891 Target_i386::optimize_tls_reloc(bool is_final, int r_type)
892 {
893   // If we are generating a shared library, then we can't do anything
894   // in the linker.
895   if (parameters->options().shared())
896     return tls::TLSOPT_NONE;
897
898   switch (r_type)
899     {
900     case elfcpp::R_386_TLS_GD:
901     case elfcpp::R_386_TLS_GOTDESC:
902     case elfcpp::R_386_TLS_DESC_CALL:
903       // These are General-Dynamic which permits fully general TLS
904       // access.  Since we know that we are generating an executable,
905       // we can convert this to Initial-Exec.  If we also know that
906       // this is a local symbol, we can further switch to Local-Exec.
907       if (is_final)
908         return tls::TLSOPT_TO_LE;
909       return tls::TLSOPT_TO_IE;
910
911     case elfcpp::R_386_TLS_LDM:
912       // This is Local-Dynamic, which refers to a local symbol in the
913       // dynamic TLS block.  Since we know that we generating an
914       // executable, we can switch to Local-Exec.
915       return tls::TLSOPT_TO_LE;
916
917     case elfcpp::R_386_TLS_LDO_32:
918       // Another type of Local-Dynamic relocation.
919       return tls::TLSOPT_TO_LE;
920
921     case elfcpp::R_386_TLS_IE:
922     case elfcpp::R_386_TLS_GOTIE:
923     case elfcpp::R_386_TLS_IE_32:
924       // These are Initial-Exec relocs which get the thread offset
925       // from the GOT.  If we know that we are linking against the
926       // local symbol, we can switch to Local-Exec, which links the
927       // thread offset into the instruction.
928       if (is_final)
929         return tls::TLSOPT_TO_LE;
930       return tls::TLSOPT_NONE;
931
932     case elfcpp::R_386_TLS_LE:
933     case elfcpp::R_386_TLS_LE_32:
934       // When we already have Local-Exec, there is nothing further we
935       // can do.
936       return tls::TLSOPT_NONE;
937
938     default:
939       gold_unreachable();
940     }
941 }
942
943 // Report an unsupported relocation against a local symbol.
944
945 void
946 Target_i386::Scan::unsupported_reloc_local(Sized_relobj<32, false>* object,
947                                            unsigned int r_type)
948 {
949   gold_error(_("%s: unsupported reloc %u against local symbol"),
950              object->name().c_str(), r_type);
951 }
952
953 // Scan a relocation for a local symbol.
954
955 inline void
956 Target_i386::Scan::local(Symbol_table* symtab,
957                          Layout* layout,
958                          Target_i386* target,
959                          Sized_relobj<32, false>* object,
960                          unsigned int data_shndx,
961                          Output_section* output_section,
962                          const elfcpp::Rel<32, false>& reloc,
963                          unsigned int r_type,
964                          const elfcpp::Sym<32, false>& lsym)
965 {
966   switch (r_type)
967     {
968     case elfcpp::R_386_NONE:
969     case elfcpp::R_386_GNU_VTINHERIT:
970     case elfcpp::R_386_GNU_VTENTRY:
971       break;
972
973     case elfcpp::R_386_32:
974       // If building a shared library (or a position-independent
975       // executable), we need to create a dynamic relocation for
976       // this location. The relocation applied at link time will
977       // apply the link-time value, so we flag the location with
978       // an R_386_RELATIVE relocation so the dynamic loader can
979       // relocate it easily.
980       if (parameters->options().output_is_position_independent())
981         {
982           Reloc_section* rel_dyn = target->rel_dyn_section(layout);
983           unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
984           rel_dyn->add_local_relative(object, r_sym, elfcpp::R_386_RELATIVE,
985                                       output_section, data_shndx,
986                                       reloc.get_r_offset());
987         }
988       break;
989
990     case elfcpp::R_386_16:
991     case elfcpp::R_386_8:
992       // If building a shared library (or a position-independent
993       // executable), we need to create a dynamic relocation for
994       // this location. Because the addend needs to remain in the
995       // data section, we need to be careful not to apply this
996       // relocation statically.
997       if (parameters->options().output_is_position_independent())
998         {
999           Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1000           unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1001           if (lsym.get_st_type() != elfcpp::STT_SECTION)
1002             rel_dyn->add_local(object, r_sym, r_type, output_section,
1003                                data_shndx, reloc.get_r_offset());
1004           else
1005             {
1006               gold_assert(lsym.get_st_value() == 0);
1007               unsigned int shndx = lsym.get_st_shndx();
1008               bool is_ordinary;
1009               shndx = object->adjust_sym_shndx(r_sym, shndx,
1010                                                &is_ordinary);
1011               if (!is_ordinary)
1012                 object->error(_("section symbol %u has bad shndx %u"),
1013                               r_sym, shndx);
1014               else
1015                 rel_dyn->add_local_section(object, shndx,
1016                                            r_type, output_section,
1017                                            data_shndx, reloc.get_r_offset());
1018             }
1019         }
1020       break;
1021
1022     case elfcpp::R_386_PC32:
1023     case elfcpp::R_386_PC16:
1024     case elfcpp::R_386_PC8:
1025       break;
1026
1027     case elfcpp::R_386_PLT32:
1028       // Since we know this is a local symbol, we can handle this as a
1029       // PC32 reloc.
1030       break;
1031
1032     case elfcpp::R_386_GOTOFF:
1033     case elfcpp::R_386_GOTPC:
1034       // We need a GOT section.
1035       target->got_section(symtab, layout);
1036       break;
1037
1038     case elfcpp::R_386_GOT32:
1039       {
1040         // The symbol requires a GOT entry.
1041         Output_data_got<32, false>* got = target->got_section(symtab, layout);
1042         unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1043         if (got->add_local(object, r_sym, GOT_TYPE_STANDARD))
1044           {
1045             // If we are generating a shared object, we need to add a
1046             // dynamic RELATIVE relocation for this symbol's GOT entry.
1047             if (parameters->options().output_is_position_independent())
1048               {
1049                 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1050                 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1051                 rel_dyn->add_local_relative(
1052                     object, r_sym, elfcpp::R_386_RELATIVE, got,
1053                     object->local_got_offset(r_sym, GOT_TYPE_STANDARD));
1054               }
1055           }
1056       }
1057       break;
1058
1059       // These are relocations which should only be seen by the
1060       // dynamic linker, and should never be seen here.
1061     case elfcpp::R_386_COPY:
1062     case elfcpp::R_386_GLOB_DAT:
1063     case elfcpp::R_386_JUMP_SLOT:
1064     case elfcpp::R_386_RELATIVE:
1065     case elfcpp::R_386_TLS_TPOFF:
1066     case elfcpp::R_386_TLS_DTPMOD32:
1067     case elfcpp::R_386_TLS_DTPOFF32:
1068     case elfcpp::R_386_TLS_TPOFF32:
1069     case elfcpp::R_386_TLS_DESC:
1070       gold_error(_("%s: unexpected reloc %u in object file"),
1071                  object->name().c_str(), r_type);
1072       break;
1073
1074       // These are initial TLS relocs, which are expected when
1075       // linking.
1076     case elfcpp::R_386_TLS_GD:            // Global-dynamic
1077     case elfcpp::R_386_TLS_GOTDESC:       // Global-dynamic (from ~oliva url)
1078     case elfcpp::R_386_TLS_DESC_CALL:
1079     case elfcpp::R_386_TLS_LDM:           // Local-dynamic
1080     case elfcpp::R_386_TLS_LDO_32:        // Alternate local-dynamic
1081     case elfcpp::R_386_TLS_IE:            // Initial-exec
1082     case elfcpp::R_386_TLS_IE_32:
1083     case elfcpp::R_386_TLS_GOTIE:
1084     case elfcpp::R_386_TLS_LE:            // Local-exec
1085     case elfcpp::R_386_TLS_LE_32:
1086       {
1087         bool output_is_shared = parameters->options().shared();
1088         const tls::Tls_optimization optimized_type
1089             = Target_i386::optimize_tls_reloc(!output_is_shared, r_type);
1090         switch (r_type)
1091           {
1092           case elfcpp::R_386_TLS_GD:          // Global-dynamic
1093             if (optimized_type == tls::TLSOPT_NONE)
1094               {
1095                 // Create a pair of GOT entries for the module index and
1096                 // dtv-relative offset.
1097                 Output_data_got<32, false>* got
1098                     = target->got_section(symtab, layout);
1099                 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1100                 unsigned int shndx = lsym.get_st_shndx();
1101                 bool is_ordinary;
1102                 shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
1103                 if (!is_ordinary)
1104                   object->error(_("local symbol %u has bad shndx %u"),
1105                               r_sym, shndx);
1106                 else
1107                   got->add_local_pair_with_rel(object, r_sym, shndx,
1108                                                GOT_TYPE_TLS_PAIR,
1109                                                target->rel_dyn_section(layout),
1110                                                elfcpp::R_386_TLS_DTPMOD32, 0);
1111               }
1112             else if (optimized_type != tls::TLSOPT_TO_LE)
1113               unsupported_reloc_local(object, r_type);
1114             break;
1115
1116           case elfcpp::R_386_TLS_GOTDESC:     // Global-dynamic (from ~oliva)
1117             target->define_tls_base_symbol(symtab, layout);
1118             if (optimized_type == tls::TLSOPT_NONE)
1119               {
1120                 // Create a double GOT entry with an R_386_TLS_DESC reloc.
1121                 Output_data_got<32, false>* got
1122                     = target->got_section(symtab, layout);
1123                 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1124                 if (!object->local_has_got_offset(r_sym, GOT_TYPE_TLS_DESC))
1125                   {
1126                     unsigned int got_offset = got->add_constant(0);
1127                     // The local symbol value is stored in the second
1128                     // GOT entry.
1129                     got->add_local(object, r_sym, GOT_TYPE_TLS_DESC);
1130                     // That set the GOT offset of the local symbol to
1131                     // point to the second entry, but we want it to
1132                     // point to the first.
1133                     object->set_local_got_offset(r_sym, GOT_TYPE_TLS_DESC,
1134                                                  got_offset);
1135                     Reloc_section* rt = target->rel_tls_desc_section(layout);
1136                     rt->add_absolute(elfcpp::R_386_TLS_DESC, got, got_offset);
1137                   }
1138               }
1139             else if (optimized_type != tls::TLSOPT_TO_LE)
1140               unsupported_reloc_local(object, r_type);
1141             break;
1142
1143           case elfcpp::R_386_TLS_DESC_CALL:
1144             break;
1145
1146           case elfcpp::R_386_TLS_LDM:         // Local-dynamic
1147             if (optimized_type == tls::TLSOPT_NONE)
1148               {
1149                 // Create a GOT entry for the module index.
1150                 target->got_mod_index_entry(symtab, layout, object);
1151               }
1152             else if (optimized_type != tls::TLSOPT_TO_LE)
1153               unsupported_reloc_local(object, r_type);
1154             break;
1155
1156           case elfcpp::R_386_TLS_LDO_32:      // Alternate local-dynamic
1157             break;
1158
1159           case elfcpp::R_386_TLS_IE:          // Initial-exec
1160           case elfcpp::R_386_TLS_IE_32:
1161           case elfcpp::R_386_TLS_GOTIE:
1162             layout->set_has_static_tls();
1163             if (optimized_type == tls::TLSOPT_NONE)
1164               {
1165                 // For the R_386_TLS_IE relocation, we need to create a
1166                 // dynamic relocation when building a shared library.
1167                 if (r_type == elfcpp::R_386_TLS_IE
1168                     && parameters->options().shared())
1169                   {
1170                     Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1171                     unsigned int r_sym
1172                         = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1173                     rel_dyn->add_local_relative(object, r_sym,
1174                                                 elfcpp::R_386_RELATIVE,
1175                                                 output_section, data_shndx,
1176                                                 reloc.get_r_offset());
1177                   }
1178                 // Create a GOT entry for the tp-relative offset.
1179                 Output_data_got<32, false>* got
1180                     = target->got_section(symtab, layout);
1181                 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1182                 unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_IE_32
1183                                            ? elfcpp::R_386_TLS_TPOFF32
1184                                            : elfcpp::R_386_TLS_TPOFF);
1185                 unsigned int got_type = (r_type == elfcpp::R_386_TLS_IE_32
1186                                          ? GOT_TYPE_TLS_OFFSET
1187                                          : GOT_TYPE_TLS_NOFFSET);
1188                 got->add_local_with_rel(object, r_sym, got_type,
1189                                         target->rel_dyn_section(layout),
1190                                         dyn_r_type);
1191               }
1192             else if (optimized_type != tls::TLSOPT_TO_LE)
1193               unsupported_reloc_local(object, r_type);
1194             break;
1195
1196           case elfcpp::R_386_TLS_LE:          // Local-exec
1197           case elfcpp::R_386_TLS_LE_32:
1198             layout->set_has_static_tls();
1199             if (output_is_shared)
1200               {
1201                 // We need to create a dynamic relocation.
1202                 gold_assert(lsym.get_st_type() != elfcpp::STT_SECTION);
1203                 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1204                 unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_LE_32
1205                                            ? elfcpp::R_386_TLS_TPOFF32
1206                                            : elfcpp::R_386_TLS_TPOFF);
1207                 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1208                 rel_dyn->add_local(object, r_sym, dyn_r_type, output_section,
1209                                    data_shndx, reloc.get_r_offset());
1210               }
1211             break;
1212
1213           default:
1214             gold_unreachable();
1215           }
1216       }
1217       break;
1218
1219     case elfcpp::R_386_32PLT:
1220     case elfcpp::R_386_TLS_GD_32:
1221     case elfcpp::R_386_TLS_GD_PUSH:
1222     case elfcpp::R_386_TLS_GD_CALL:
1223     case elfcpp::R_386_TLS_GD_POP:
1224     case elfcpp::R_386_TLS_LDM_32:
1225     case elfcpp::R_386_TLS_LDM_PUSH:
1226     case elfcpp::R_386_TLS_LDM_CALL:
1227     case elfcpp::R_386_TLS_LDM_POP:
1228     case elfcpp::R_386_USED_BY_INTEL_200:
1229     default:
1230       unsupported_reloc_local(object, r_type);
1231       break;
1232     }
1233 }
1234
1235 // Report an unsupported relocation against a global symbol.
1236
1237 void
1238 Target_i386::Scan::unsupported_reloc_global(Sized_relobj<32, false>* object,
1239                                             unsigned int r_type,
1240                                             Symbol* gsym)
1241 {
1242   gold_error(_("%s: unsupported reloc %u against global symbol %s"),
1243              object->name().c_str(), r_type, gsym->demangled_name().c_str());
1244 }
1245
1246 inline bool
1247 Target_i386::Scan::possible_function_pointer_reloc(unsigned int r_type)
1248 {
1249   switch (r_type)
1250     {
1251     case elfcpp::R_386_32:
1252     case elfcpp::R_386_16:
1253     case elfcpp::R_386_8:
1254     case elfcpp::R_386_GOTOFF:
1255     case elfcpp::R_386_GOT32:
1256       {
1257         return true;
1258       }
1259     default:
1260       return false;
1261     }
1262   return false;
1263 }
1264
1265 inline bool
1266 Target_i386::Scan::local_reloc_may_be_function_pointer(
1267   Symbol_table* ,
1268   Layout* ,
1269   Target_i386* ,
1270   Sized_relobj<32, false>* ,
1271   unsigned int ,
1272   Output_section* ,
1273   const elfcpp::Rel<32, false>& ,
1274   unsigned int r_type,
1275   const elfcpp::Sym<32, false>&)
1276 {
1277   return possible_function_pointer_reloc(r_type);
1278 }
1279
1280 inline bool
1281 Target_i386::Scan::global_reloc_may_be_function_pointer(
1282   Symbol_table* ,
1283   Layout* ,
1284   Target_i386* ,
1285   Sized_relobj<32, false>* ,
1286   unsigned int ,
1287   Output_section* ,
1288   const elfcpp::Rel<32, false>& ,
1289   unsigned int r_type,
1290   Symbol*)
1291 {
1292   return possible_function_pointer_reloc(r_type);
1293 }
1294
1295 // Scan a relocation for a global symbol.
1296
1297 inline void
1298 Target_i386::Scan::global(Symbol_table* symtab,
1299                           Layout* layout,
1300                           Target_i386* target,
1301                           Sized_relobj<32, false>* object,
1302                           unsigned int data_shndx,
1303                           Output_section* output_section,
1304                           const elfcpp::Rel<32, false>& reloc,
1305                           unsigned int r_type,
1306                           Symbol* gsym)
1307 {
1308   switch (r_type)
1309     {
1310     case elfcpp::R_386_NONE:
1311     case elfcpp::R_386_GNU_VTINHERIT:
1312     case elfcpp::R_386_GNU_VTENTRY:
1313       break;
1314
1315     case elfcpp::R_386_32:
1316     case elfcpp::R_386_16:
1317     case elfcpp::R_386_8:
1318       {
1319         // Make a PLT entry if necessary.
1320         if (gsym->needs_plt_entry())
1321           {
1322             target->make_plt_entry(symtab, layout, gsym);
1323             // Since this is not a PC-relative relocation, we may be
1324             // taking the address of a function. In that case we need to
1325             // set the entry in the dynamic symbol table to the address of
1326             // the PLT entry.
1327             if (gsym->is_from_dynobj() && !parameters->options().shared())
1328               gsym->set_needs_dynsym_value();
1329           }
1330         // Make a dynamic relocation if necessary.
1331         if (gsym->needs_dynamic_reloc(Symbol::ABSOLUTE_REF))
1332           {
1333             if (gsym->may_need_copy_reloc())
1334               {
1335                 target->copy_reloc(symtab, layout, object,
1336                                    data_shndx, output_section, gsym, reloc);
1337               }
1338             else if (r_type == elfcpp::R_386_32
1339                      && gsym->can_use_relative_reloc(false))
1340               {
1341                 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1342                 rel_dyn->add_global_relative(gsym, elfcpp::R_386_RELATIVE,
1343                                              output_section, object,
1344                                              data_shndx, reloc.get_r_offset());
1345               }
1346             else
1347               {
1348                 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1349                 rel_dyn->add_global(gsym, r_type, output_section, object,
1350                                     data_shndx, reloc.get_r_offset());
1351               }
1352           }
1353       }
1354       break;
1355
1356     case elfcpp::R_386_PC32:
1357     case elfcpp::R_386_PC16:
1358     case elfcpp::R_386_PC8:
1359       {
1360         // Make a PLT entry if necessary.
1361         if (gsym->needs_plt_entry())
1362           {
1363             // These relocations are used for function calls only in
1364             // non-PIC code.  For a 32-bit relocation in a shared library,
1365             // we'll need a text relocation anyway, so we can skip the
1366             // PLT entry and let the dynamic linker bind the call directly
1367             // to the target.  For smaller relocations, we should use a
1368             // PLT entry to ensure that the call can reach.
1369             if (!parameters->options().shared()
1370                 || r_type != elfcpp::R_386_PC32)
1371               target->make_plt_entry(symtab, layout, gsym);
1372           }
1373         // Make a dynamic relocation if necessary.
1374         int flags = Symbol::NON_PIC_REF;
1375         if (gsym->is_func())
1376           flags |= Symbol::FUNCTION_CALL;
1377         if (gsym->needs_dynamic_reloc(flags))
1378           {
1379             if (gsym->may_need_copy_reloc())
1380               {
1381                 target->copy_reloc(symtab, layout, object,
1382                                    data_shndx, output_section, gsym, reloc);
1383               }
1384             else
1385               {
1386                 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1387                 rel_dyn->add_global(gsym, r_type, output_section, object,
1388                                     data_shndx, reloc.get_r_offset());
1389               }
1390           }
1391       }
1392       break;
1393
1394     case elfcpp::R_386_GOT32:
1395       {
1396         // The symbol requires a GOT entry.
1397         Output_data_got<32, false>* got = target->got_section(symtab, layout);
1398         if (gsym->final_value_is_known())
1399           got->add_global(gsym, GOT_TYPE_STANDARD);
1400         else
1401           {
1402             // If this symbol is not fully resolved, we need to add a
1403             // GOT entry with a dynamic relocation.
1404             Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1405             if (gsym->is_from_dynobj()
1406                 || gsym->is_undefined()
1407                 || gsym->is_preemptible())
1408               got->add_global_with_rel(gsym, GOT_TYPE_STANDARD,
1409                                        rel_dyn, elfcpp::R_386_GLOB_DAT);
1410             else
1411               {
1412                 if (got->add_global(gsym, GOT_TYPE_STANDARD))
1413                   rel_dyn->add_global_relative(
1414                       gsym, elfcpp::R_386_RELATIVE, got,
1415                       gsym->got_offset(GOT_TYPE_STANDARD));
1416               }
1417           }
1418       }
1419       break;
1420
1421     case elfcpp::R_386_PLT32:
1422       // If the symbol is fully resolved, this is just a PC32 reloc.
1423       // Otherwise we need a PLT entry.
1424       if (gsym->final_value_is_known())
1425         break;
1426       // If building a shared library, we can also skip the PLT entry
1427       // if the symbol is defined in the output file and is protected
1428       // or hidden.
1429       if (gsym->is_defined()
1430           && !gsym->is_from_dynobj()
1431           && !gsym->is_preemptible())
1432         break;
1433       target->make_plt_entry(symtab, layout, gsym);
1434       break;
1435
1436     case elfcpp::R_386_GOTOFF:
1437     case elfcpp::R_386_GOTPC:
1438       // We need a GOT section.
1439       target->got_section(symtab, layout);
1440       break;
1441
1442       // These are relocations which should only be seen by the
1443       // dynamic linker, and should never be seen here.
1444     case elfcpp::R_386_COPY:
1445     case elfcpp::R_386_GLOB_DAT:
1446     case elfcpp::R_386_JUMP_SLOT:
1447     case elfcpp::R_386_RELATIVE:
1448     case elfcpp::R_386_TLS_TPOFF:
1449     case elfcpp::R_386_TLS_DTPMOD32:
1450     case elfcpp::R_386_TLS_DTPOFF32:
1451     case elfcpp::R_386_TLS_TPOFF32:
1452     case elfcpp::R_386_TLS_DESC:
1453       gold_error(_("%s: unexpected reloc %u in object file"),
1454                  object->name().c_str(), r_type);
1455       break;
1456
1457       // These are initial tls relocs, which are expected when
1458       // linking.
1459     case elfcpp::R_386_TLS_GD:            // Global-dynamic
1460     case elfcpp::R_386_TLS_GOTDESC:       // Global-dynamic (from ~oliva url)
1461     case elfcpp::R_386_TLS_DESC_CALL:
1462     case elfcpp::R_386_TLS_LDM:           // Local-dynamic
1463     case elfcpp::R_386_TLS_LDO_32:        // Alternate local-dynamic
1464     case elfcpp::R_386_TLS_IE:            // Initial-exec
1465     case elfcpp::R_386_TLS_IE_32:
1466     case elfcpp::R_386_TLS_GOTIE:
1467     case elfcpp::R_386_TLS_LE:            // Local-exec
1468     case elfcpp::R_386_TLS_LE_32:
1469       {
1470         const bool is_final = gsym->final_value_is_known();
1471         const tls::Tls_optimization optimized_type
1472             = Target_i386::optimize_tls_reloc(is_final, r_type);
1473         switch (r_type)
1474           {
1475           case elfcpp::R_386_TLS_GD:          // Global-dynamic
1476             if (optimized_type == tls::TLSOPT_NONE)
1477               {
1478                 // Create a pair of GOT entries for the module index and
1479                 // dtv-relative offset.
1480                 Output_data_got<32, false>* got
1481                     = target->got_section(symtab, layout);
1482                 got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_PAIR,
1483                                              target->rel_dyn_section(layout),
1484                                              elfcpp::R_386_TLS_DTPMOD32,
1485                                              elfcpp::R_386_TLS_DTPOFF32);
1486               }
1487             else if (optimized_type == tls::TLSOPT_TO_IE)
1488               {
1489                 // Create a GOT entry for the tp-relative offset.
1490                 Output_data_got<32, false>* got
1491                     = target->got_section(symtab, layout);
1492                 got->add_global_with_rel(gsym, GOT_TYPE_TLS_NOFFSET,
1493                                          target->rel_dyn_section(layout),
1494                                          elfcpp::R_386_TLS_TPOFF);
1495               }
1496             else if (optimized_type != tls::TLSOPT_TO_LE)
1497               unsupported_reloc_global(object, r_type, gsym);
1498             break;
1499
1500           case elfcpp::R_386_TLS_GOTDESC:     // Global-dynamic (~oliva url)
1501             target->define_tls_base_symbol(symtab, layout);
1502             if (optimized_type == tls::TLSOPT_NONE)
1503               {
1504                 // Create a double GOT entry with an R_386_TLS_DESC reloc.
1505                 Output_data_got<32, false>* got
1506                     = target->got_section(symtab, layout);
1507                 Reloc_section* rt = target->rel_tls_desc_section(layout);
1508                 got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_DESC, rt,
1509                                              elfcpp::R_386_TLS_DESC, 0);
1510               }
1511             else if (optimized_type == tls::TLSOPT_TO_IE)
1512               {
1513                 // Create a GOT entry for the tp-relative offset.
1514                 Output_data_got<32, false>* got
1515                     = target->got_section(symtab, layout);
1516                 got->add_global_with_rel(gsym, GOT_TYPE_TLS_NOFFSET,
1517                                          target->rel_dyn_section(layout),
1518                                          elfcpp::R_386_TLS_TPOFF);
1519               }
1520             else if (optimized_type != tls::TLSOPT_TO_LE)
1521               unsupported_reloc_global(object, r_type, gsym);
1522             break;
1523
1524           case elfcpp::R_386_TLS_DESC_CALL:
1525             break;
1526
1527           case elfcpp::R_386_TLS_LDM:         // Local-dynamic
1528             if (optimized_type == tls::TLSOPT_NONE)
1529               {
1530                 // Create a GOT entry for the module index.
1531                 target->got_mod_index_entry(symtab, layout, object);
1532               }
1533             else if (optimized_type != tls::TLSOPT_TO_LE)
1534               unsupported_reloc_global(object, r_type, gsym);
1535             break;
1536
1537           case elfcpp::R_386_TLS_LDO_32:      // Alternate local-dynamic
1538             break;
1539
1540           case elfcpp::R_386_TLS_IE:          // Initial-exec
1541           case elfcpp::R_386_TLS_IE_32:
1542           case elfcpp::R_386_TLS_GOTIE:
1543             layout->set_has_static_tls();
1544             if (optimized_type == tls::TLSOPT_NONE)
1545               {
1546                 // For the R_386_TLS_IE relocation, we need to create a
1547                 // dynamic relocation when building a shared library.
1548                 if (r_type == elfcpp::R_386_TLS_IE
1549                     && parameters->options().shared())
1550                   {
1551                     Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1552                     rel_dyn->add_global_relative(gsym, elfcpp::R_386_RELATIVE,
1553                                                  output_section, object,
1554                                                  data_shndx,
1555                                                  reloc.get_r_offset());
1556                   }
1557                 // Create a GOT entry for the tp-relative offset.
1558                 Output_data_got<32, false>* got
1559                     = target->got_section(symtab, layout);
1560                 unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_IE_32
1561                                            ? elfcpp::R_386_TLS_TPOFF32
1562                                            : elfcpp::R_386_TLS_TPOFF);
1563                 unsigned int got_type = (r_type == elfcpp::R_386_TLS_IE_32
1564                                          ? GOT_TYPE_TLS_OFFSET
1565                                          : GOT_TYPE_TLS_NOFFSET);
1566                 got->add_global_with_rel(gsym, got_type,
1567                                          target->rel_dyn_section(layout),
1568                                          dyn_r_type);
1569               }
1570             else if (optimized_type != tls::TLSOPT_TO_LE)
1571               unsupported_reloc_global(object, r_type, gsym);
1572             break;
1573
1574           case elfcpp::R_386_TLS_LE:          // Local-exec
1575           case elfcpp::R_386_TLS_LE_32:
1576             layout->set_has_static_tls();
1577             if (parameters->options().shared())
1578               {
1579                 // We need to create a dynamic relocation.
1580                 unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_LE_32
1581                                            ? elfcpp::R_386_TLS_TPOFF32
1582                                            : elfcpp::R_386_TLS_TPOFF);
1583                 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1584                 rel_dyn->add_global(gsym, dyn_r_type, output_section, object,
1585                                     data_shndx, reloc.get_r_offset());
1586               }
1587             break;
1588
1589           default:
1590             gold_unreachable();
1591           }
1592       }
1593       break;
1594
1595     case elfcpp::R_386_32PLT:
1596     case elfcpp::R_386_TLS_GD_32:
1597     case elfcpp::R_386_TLS_GD_PUSH:
1598     case elfcpp::R_386_TLS_GD_CALL:
1599     case elfcpp::R_386_TLS_GD_POP:
1600     case elfcpp::R_386_TLS_LDM_32:
1601     case elfcpp::R_386_TLS_LDM_PUSH:
1602     case elfcpp::R_386_TLS_LDM_CALL:
1603     case elfcpp::R_386_TLS_LDM_POP:
1604     case elfcpp::R_386_USED_BY_INTEL_200:
1605     default:
1606       unsupported_reloc_global(object, r_type, gsym);
1607       break;
1608     }
1609 }
1610
1611 // Process relocations for gc.
1612
1613 void
1614 Target_i386::gc_process_relocs(Symbol_table* symtab,
1615                                Layout* layout,
1616                                Sized_relobj<32, false>* object,
1617                                unsigned int data_shndx,
1618                                unsigned int,
1619                                const unsigned char* prelocs,
1620                                size_t reloc_count,
1621                                Output_section* output_section,
1622                                bool needs_special_offset_handling,
1623                                size_t local_symbol_count,
1624                                const unsigned char* plocal_symbols)
1625 {
1626   gold::gc_process_relocs<32, false, Target_i386, elfcpp::SHT_REL,
1627                           Target_i386::Scan,
1628                           Target_i386::Relocatable_size_for_reloc>(
1629     symtab,
1630     layout,
1631     this,
1632     object,
1633     data_shndx,
1634     prelocs,
1635     reloc_count,
1636     output_section,
1637     needs_special_offset_handling,
1638     local_symbol_count,
1639     plocal_symbols);
1640 }
1641
1642 // Scan relocations for a section.
1643
1644 void
1645 Target_i386::scan_relocs(Symbol_table* symtab,
1646                          Layout* layout,
1647                          Sized_relobj<32, false>* object,
1648                          unsigned int data_shndx,
1649                          unsigned int sh_type,
1650                          const unsigned char* prelocs,
1651                          size_t reloc_count,
1652                          Output_section* output_section,
1653                          bool needs_special_offset_handling,
1654                          size_t local_symbol_count,
1655                          const unsigned char* plocal_symbols)
1656 {
1657   if (sh_type == elfcpp::SHT_RELA)
1658     {
1659       gold_error(_("%s: unsupported RELA reloc section"),
1660                  object->name().c_str());
1661       return;
1662     }
1663
1664   gold::scan_relocs<32, false, Target_i386, elfcpp::SHT_REL,
1665                     Target_i386::Scan>(
1666     symtab,
1667     layout,
1668     this,
1669     object,
1670     data_shndx,
1671     prelocs,
1672     reloc_count,
1673     output_section,
1674     needs_special_offset_handling,
1675     local_symbol_count,
1676     plocal_symbols);
1677 }
1678
1679 // Finalize the sections.
1680
1681 void
1682 Target_i386::do_finalize_sections(
1683     Layout* layout,
1684     const Input_objects*,
1685     Symbol_table* symtab)
1686 {
1687   const Reloc_section* rel_plt = (this->plt_ == NULL
1688                                   ? NULL
1689                                   : this->plt_->rel_plt());
1690   layout->add_target_dynamic_tags(true, this->got_plt_, rel_plt,
1691                                   this->rel_dyn_, true, false);
1692
1693   // Emit any relocs we saved in an attempt to avoid generating COPY
1694   // relocs.
1695   if (this->copy_relocs_.any_saved_relocs())
1696     this->copy_relocs_.emit(this->rel_dyn_section(layout));
1697
1698   // Set the size of the _GLOBAL_OFFSET_TABLE_ symbol to the size of
1699   // the .got.plt section.
1700   Symbol* sym = this->global_offset_table_;
1701   if (sym != NULL)
1702     {
1703       uint32_t data_size = this->got_plt_->current_data_size();
1704       symtab->get_sized_symbol<32>(sym)->set_symsize(data_size);
1705     }
1706 }
1707
1708 // Return whether a direct absolute static relocation needs to be applied.
1709 // In cases where Scan::local() or Scan::global() has created
1710 // a dynamic relocation other than R_386_RELATIVE, the addend
1711 // of the relocation is carried in the data, and we must not
1712 // apply the static relocation.
1713
1714 inline bool
1715 Target_i386::Relocate::should_apply_static_reloc(const Sized_symbol<32>* gsym,
1716                                                  int ref_flags,
1717                                                  bool is_32bit,
1718                                                  Output_section* output_section)
1719 {
1720   // If the output section is not allocated, then we didn't call
1721   // scan_relocs, we didn't create a dynamic reloc, and we must apply
1722   // the reloc here.
1723   if ((output_section->flags() & elfcpp::SHF_ALLOC) == 0)
1724     return true;
1725
1726   // For local symbols, we will have created a non-RELATIVE dynamic
1727   // relocation only if (a) the output is position independent,
1728   // (b) the relocation is absolute (not pc- or segment-relative), and
1729   // (c) the relocation is not 32 bits wide.
1730   if (gsym == NULL)
1731     return !(parameters->options().output_is_position_independent()
1732              && (ref_flags & Symbol::ABSOLUTE_REF)
1733              && !is_32bit);
1734
1735   // For global symbols, we use the same helper routines used in the
1736   // scan pass.  If we did not create a dynamic relocation, or if we
1737   // created a RELATIVE dynamic relocation, we should apply the static
1738   // relocation.
1739   bool has_dyn = gsym->needs_dynamic_reloc(ref_flags);
1740   bool is_rel = (ref_flags & Symbol::ABSOLUTE_REF)
1741                 && gsym->can_use_relative_reloc(ref_flags
1742                                                 & Symbol::FUNCTION_CALL);
1743   return !has_dyn || is_rel;
1744 }
1745
1746 // Perform a relocation.
1747
1748 inline bool
1749 Target_i386::Relocate::relocate(const Relocate_info<32, false>* relinfo,
1750                                 Target_i386* target,
1751                                 Output_section *output_section,
1752                                 size_t relnum,
1753                                 const elfcpp::Rel<32, false>& rel,
1754                                 unsigned int r_type,
1755                                 const Sized_symbol<32>* gsym,
1756                                 const Symbol_value<32>* psymval,
1757                                 unsigned char* view,
1758                                 elfcpp::Elf_types<32>::Elf_Addr address,
1759                                 section_size_type view_size)
1760 {
1761   if (this->skip_call_tls_get_addr_)
1762     {
1763       if ((r_type != elfcpp::R_386_PLT32
1764            && r_type != elfcpp::R_386_PC32)
1765           || gsym == NULL
1766           || strcmp(gsym->name(), "___tls_get_addr") != 0)
1767         gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
1768                                _("missing expected TLS relocation"));
1769       else
1770         {
1771           this->skip_call_tls_get_addr_ = false;
1772           return false;
1773         }
1774     }
1775
1776   // Pick the value to use for symbols defined in shared objects.
1777   Symbol_value<32> symval;
1778   if (gsym != NULL
1779       && gsym->use_plt_offset(r_type == elfcpp::R_386_PC8
1780                               || r_type == elfcpp::R_386_PC16
1781                               || r_type == elfcpp::R_386_PC32))
1782     {
1783       symval.set_output_value(target->plt_section()->address()
1784                               + gsym->plt_offset());
1785       psymval = &symval;
1786     }
1787
1788   const Sized_relobj<32, false>* object = relinfo->object;
1789
1790   // Get the GOT offset if needed.
1791   // The GOT pointer points to the end of the GOT section.
1792   // We need to subtract the size of the GOT section to get
1793   // the actual offset to use in the relocation.
1794   bool have_got_offset = false;
1795   unsigned int got_offset = 0;
1796   switch (r_type)
1797     {
1798     case elfcpp::R_386_GOT32:
1799       if (gsym != NULL)
1800         {
1801           gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
1802           got_offset = (gsym->got_offset(GOT_TYPE_STANDARD)
1803                         - target->got_size());
1804         }
1805       else
1806         {
1807           unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
1808           gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD));
1809           got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD)
1810                         - target->got_size());
1811         }
1812       have_got_offset = true;
1813       break;
1814
1815     default:
1816       break;
1817     }
1818
1819   switch (r_type)
1820     {
1821     case elfcpp::R_386_NONE:
1822     case elfcpp::R_386_GNU_VTINHERIT:
1823     case elfcpp::R_386_GNU_VTENTRY:
1824       break;
1825
1826     case elfcpp::R_386_32:
1827       if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
1828                                     output_section))
1829         Relocate_functions<32, false>::rel32(view, object, psymval);
1830       break;
1831
1832     case elfcpp::R_386_PC32:
1833       {
1834         int ref_flags = Symbol::NON_PIC_REF;
1835         if (gsym != NULL && gsym->is_func())
1836           ref_flags |= Symbol::FUNCTION_CALL;
1837         if (should_apply_static_reloc(gsym, ref_flags, true, output_section))
1838           Relocate_functions<32, false>::pcrel32(view, object, psymval, address);
1839       }
1840       break;
1841
1842     case elfcpp::R_386_16:
1843       if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
1844                                     output_section))
1845         Relocate_functions<32, false>::rel16(view, object, psymval);
1846       break;
1847
1848     case elfcpp::R_386_PC16:
1849       {
1850         int ref_flags = Symbol::NON_PIC_REF;
1851         if (gsym != NULL && gsym->is_func())
1852           ref_flags |= Symbol::FUNCTION_CALL;
1853         if (should_apply_static_reloc(gsym, ref_flags, false, output_section))
1854           Relocate_functions<32, false>::pcrel16(view, object, psymval, address);
1855       }
1856       break;
1857
1858     case elfcpp::R_386_8:
1859       if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
1860                                     output_section))
1861         Relocate_functions<32, false>::rel8(view, object, psymval);
1862       break;
1863
1864     case elfcpp::R_386_PC8:
1865       {
1866         int ref_flags = Symbol::NON_PIC_REF;
1867         if (gsym != NULL && gsym->is_func())
1868           ref_flags |= Symbol::FUNCTION_CALL;
1869         if (should_apply_static_reloc(gsym, ref_flags, false,
1870                                       output_section))
1871           Relocate_functions<32, false>::pcrel8(view, object, psymval, address);
1872       }
1873       break;
1874
1875     case elfcpp::R_386_PLT32:
1876       gold_assert(gsym == NULL
1877                   || gsym->has_plt_offset()
1878                   || gsym->final_value_is_known()
1879                   || (gsym->is_defined()
1880                       && !gsym->is_from_dynobj()
1881                       && !gsym->is_preemptible()));
1882       Relocate_functions<32, false>::pcrel32(view, object, psymval, address);
1883       break;
1884
1885     case elfcpp::R_386_GOT32:
1886       gold_assert(have_got_offset);
1887       Relocate_functions<32, false>::rel32(view, got_offset);
1888       break;
1889
1890     case elfcpp::R_386_GOTOFF:
1891       {
1892         elfcpp::Elf_types<32>::Elf_Addr value;
1893         value = (psymval->value(object, 0)
1894                  - target->got_plt_section()->address());
1895         Relocate_functions<32, false>::rel32(view, value);
1896       }
1897       break;
1898
1899     case elfcpp::R_386_GOTPC:
1900       {
1901         elfcpp::Elf_types<32>::Elf_Addr value;
1902         value = target->got_plt_section()->address();
1903         Relocate_functions<32, false>::pcrel32(view, value, address);
1904       }
1905       break;
1906
1907     case elfcpp::R_386_COPY:
1908     case elfcpp::R_386_GLOB_DAT:
1909     case elfcpp::R_386_JUMP_SLOT:
1910     case elfcpp::R_386_RELATIVE:
1911       // These are outstanding tls relocs, which are unexpected when
1912       // linking.
1913     case elfcpp::R_386_TLS_TPOFF:
1914     case elfcpp::R_386_TLS_DTPMOD32:
1915     case elfcpp::R_386_TLS_DTPOFF32:
1916     case elfcpp::R_386_TLS_TPOFF32:
1917     case elfcpp::R_386_TLS_DESC:
1918       gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
1919                              _("unexpected reloc %u in object file"),
1920                              r_type);
1921       break;
1922
1923       // These are initial tls relocs, which are expected when
1924       // linking.
1925     case elfcpp::R_386_TLS_GD:             // Global-dynamic
1926     case elfcpp::R_386_TLS_GOTDESC:        // Global-dynamic (from ~oliva url)
1927     case elfcpp::R_386_TLS_DESC_CALL:
1928     case elfcpp::R_386_TLS_LDM:            // Local-dynamic
1929     case elfcpp::R_386_TLS_LDO_32:         // Alternate local-dynamic
1930     case elfcpp::R_386_TLS_IE:             // Initial-exec
1931     case elfcpp::R_386_TLS_IE_32:
1932     case elfcpp::R_386_TLS_GOTIE:
1933     case elfcpp::R_386_TLS_LE:             // Local-exec
1934     case elfcpp::R_386_TLS_LE_32:
1935       this->relocate_tls(relinfo, target, relnum, rel, r_type, gsym, psymval,
1936                          view, address, view_size);
1937       break;
1938
1939     case elfcpp::R_386_32PLT:
1940     case elfcpp::R_386_TLS_GD_32:
1941     case elfcpp::R_386_TLS_GD_PUSH:
1942     case elfcpp::R_386_TLS_GD_CALL:
1943     case elfcpp::R_386_TLS_GD_POP:
1944     case elfcpp::R_386_TLS_LDM_32:
1945     case elfcpp::R_386_TLS_LDM_PUSH:
1946     case elfcpp::R_386_TLS_LDM_CALL:
1947     case elfcpp::R_386_TLS_LDM_POP:
1948     case elfcpp::R_386_USED_BY_INTEL_200:
1949     default:
1950       gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
1951                              _("unsupported reloc %u"),
1952                              r_type);
1953       break;
1954     }
1955
1956   return true;
1957 }
1958
1959 // Perform a TLS relocation.
1960
1961 inline void
1962 Target_i386::Relocate::relocate_tls(const Relocate_info<32, false>* relinfo,
1963                                     Target_i386* target,
1964                                     size_t relnum,
1965                                     const elfcpp::Rel<32, false>& rel,
1966                                     unsigned int r_type,
1967                                     const Sized_symbol<32>* gsym,
1968                                     const Symbol_value<32>* psymval,
1969                                     unsigned char* view,
1970                                     elfcpp::Elf_types<32>::Elf_Addr,
1971                                     section_size_type view_size)
1972 {
1973   Output_segment* tls_segment = relinfo->layout->tls_segment();
1974
1975   const Sized_relobj<32, false>* object = relinfo->object;
1976
1977   elfcpp::Elf_types<32>::Elf_Addr value = psymval->value(object, 0);
1978
1979   const bool is_final = (gsym == NULL
1980                          ? !parameters->options().shared()
1981                          : gsym->final_value_is_known());
1982   const tls::Tls_optimization optimized_type
1983       = Target_i386::optimize_tls_reloc(is_final, r_type);
1984   switch (r_type)
1985     {
1986     case elfcpp::R_386_TLS_GD:           // Global-dynamic
1987       if (optimized_type == tls::TLSOPT_TO_LE)
1988         {
1989           gold_assert(tls_segment != NULL);
1990           this->tls_gd_to_le(relinfo, relnum, tls_segment,
1991                              rel, r_type, value, view,
1992                              view_size);
1993           break;
1994         }
1995       else
1996         {
1997           unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE
1998                                    ? GOT_TYPE_TLS_NOFFSET
1999                                    : GOT_TYPE_TLS_PAIR);
2000           unsigned int got_offset;
2001           if (gsym != NULL)
2002             {
2003               gold_assert(gsym->has_got_offset(got_type));
2004               got_offset = gsym->got_offset(got_type) - target->got_size();
2005             }
2006           else
2007             {
2008               unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
2009               gold_assert(object->local_has_got_offset(r_sym, got_type));
2010               got_offset = (object->local_got_offset(r_sym, got_type)
2011                             - target->got_size());
2012             }
2013           if (optimized_type == tls::TLSOPT_TO_IE)
2014             {
2015               gold_assert(tls_segment != NULL);
2016               this->tls_gd_to_ie(relinfo, relnum, tls_segment, rel, r_type,
2017                                  got_offset, view, view_size);
2018               break;
2019             }
2020           else if (optimized_type == tls::TLSOPT_NONE)
2021             {
2022               // Relocate the field with the offset of the pair of GOT
2023               // entries.
2024               Relocate_functions<32, false>::rel32(view, got_offset);
2025               break;
2026             }
2027         }
2028       gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
2029                              _("unsupported reloc %u"),
2030                              r_type);
2031       break;
2032
2033     case elfcpp::R_386_TLS_GOTDESC:      // Global-dynamic (from ~oliva url)
2034     case elfcpp::R_386_TLS_DESC_CALL:
2035       this->local_dynamic_type_ = LOCAL_DYNAMIC_GNU;
2036       if (optimized_type == tls::TLSOPT_TO_LE)
2037         {
2038           gold_assert(tls_segment != NULL);
2039           this->tls_desc_gd_to_le(relinfo, relnum, tls_segment,
2040                                   rel, r_type, value, view,
2041                                   view_size);
2042           break;
2043         }
2044       else
2045         {
2046           unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE
2047                                    ? GOT_TYPE_TLS_NOFFSET
2048                                    : GOT_TYPE_TLS_DESC);
2049           unsigned int got_offset;
2050           if (gsym != NULL)
2051             {
2052               gold_assert(gsym->has_got_offset(got_type));
2053               got_offset = gsym->got_offset(got_type) - target->got_size();
2054             }
2055           else
2056             {
2057               unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
2058               gold_assert(object->local_has_got_offset(r_sym, got_type));
2059               got_offset = (object->local_got_offset(r_sym, got_type)
2060                             - target->got_size());
2061             }
2062           if (optimized_type == tls::TLSOPT_TO_IE)
2063             {
2064               gold_assert(tls_segment != NULL);
2065               this->tls_desc_gd_to_ie(relinfo, relnum, tls_segment, rel, r_type,
2066                                       got_offset, view, view_size);
2067               break;
2068             }
2069           else if (optimized_type == tls::TLSOPT_NONE)
2070             {
2071               if (r_type == elfcpp::R_386_TLS_GOTDESC)
2072                 {
2073                   // Relocate the field with the offset of the pair of GOT
2074                   // entries.
2075                   Relocate_functions<32, false>::rel32(view, got_offset);
2076                 }
2077               break;
2078             }
2079         }
2080       gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
2081                              _("unsupported reloc %u"),
2082                              r_type);
2083       break;
2084
2085     case elfcpp::R_386_TLS_LDM:          // Local-dynamic
2086       if (this->local_dynamic_type_ == LOCAL_DYNAMIC_SUN)
2087         {
2088           gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
2089                                  _("both SUN and GNU model "
2090                                    "TLS relocations"));
2091           break;
2092         }
2093       this->local_dynamic_type_ = LOCAL_DYNAMIC_GNU;
2094       if (optimized_type == tls::TLSOPT_TO_LE)
2095         {
2096           gold_assert(tls_segment != NULL);
2097           this->tls_ld_to_le(relinfo, relnum, tls_segment, rel, r_type,
2098                              value, view, view_size);
2099           break;
2100         }
2101       else if (optimized_type == tls::TLSOPT_NONE)
2102         {
2103           // Relocate the field with the offset of the GOT entry for
2104           // the module index.
2105           unsigned int got_offset;
2106           got_offset = (target->got_mod_index_entry(NULL, NULL, NULL)
2107                         - target->got_size());
2108           Relocate_functions<32, false>::rel32(view, got_offset);
2109           break;
2110         }
2111       gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
2112                              _("unsupported reloc %u"),
2113                              r_type);
2114       break;
2115
2116     case elfcpp::R_386_TLS_LDO_32:       // Alternate local-dynamic
2117       if (optimized_type == tls::TLSOPT_TO_LE)
2118         {
2119           // This reloc can appear in debugging sections, in which
2120           // case we must not convert to local-exec.  We decide what
2121           // to do based on whether the section is marked as
2122           // containing executable code.  That is what the GNU linker
2123           // does as well.
2124           elfcpp::Shdr<32, false> shdr(relinfo->data_shdr);
2125           if ((shdr.get_sh_flags() & elfcpp::SHF_EXECINSTR) != 0)
2126             {
2127               gold_assert(tls_segment != NULL);
2128               value -= tls_segment->memsz();
2129             }
2130         }
2131       Relocate_functions<32, false>::rel32(view, value);
2132       break;
2133
2134     case elfcpp::R_386_TLS_IE:           // Initial-exec
2135     case elfcpp::R_386_TLS_GOTIE:
2136     case elfcpp::R_386_TLS_IE_32:
2137       if (optimized_type == tls::TLSOPT_TO_LE)
2138         {
2139           gold_assert(tls_segment != NULL);
2140           Target_i386::Relocate::tls_ie_to_le(relinfo, relnum, tls_segment,
2141                                               rel, r_type, value, view,
2142                                               view_size);
2143           break;
2144         }
2145       else if (optimized_type == tls::TLSOPT_NONE)
2146         {
2147           // Relocate the field with the offset of the GOT entry for
2148           // the tp-relative offset of the symbol.
2149           unsigned int got_type = (r_type == elfcpp::R_386_TLS_IE_32
2150                                    ? GOT_TYPE_TLS_OFFSET
2151                                    : GOT_TYPE_TLS_NOFFSET);
2152           unsigned int got_offset;
2153           if (gsym != NULL)
2154             {
2155               gold_assert(gsym->has_got_offset(got_type));
2156               got_offset = gsym->got_offset(got_type);
2157             }
2158           else
2159             {
2160               unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
2161               gold_assert(object->local_has_got_offset(r_sym, got_type));
2162               got_offset = object->local_got_offset(r_sym, got_type);
2163             }
2164           // For the R_386_TLS_IE relocation, we need to apply the
2165           // absolute address of the GOT entry.
2166           if (r_type == elfcpp::R_386_TLS_IE)
2167             got_offset += target->got_plt_section()->address();
2168           // All GOT offsets are relative to the end of the GOT.
2169           got_offset -= target->got_size();
2170           Relocate_functions<32, false>::rel32(view, got_offset);
2171           break;
2172         }
2173       gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
2174                              _("unsupported reloc %u"),
2175                              r_type);
2176       break;
2177
2178     case elfcpp::R_386_TLS_LE:           // Local-exec
2179       // If we're creating a shared library, a dynamic relocation will
2180       // have been created for this location, so do not apply it now.
2181       if (!parameters->options().shared())
2182         {
2183           gold_assert(tls_segment != NULL);
2184           value -= tls_segment->memsz();
2185           Relocate_functions<32, false>::rel32(view, value);
2186         }
2187       break;
2188
2189     case elfcpp::R_386_TLS_LE_32:
2190       // If we're creating a shared library, a dynamic relocation will
2191       // have been created for this location, so do not apply it now.
2192       if (!parameters->options().shared())
2193         {
2194           gold_assert(tls_segment != NULL);
2195           value = tls_segment->memsz() - value;
2196           Relocate_functions<32, false>::rel32(view, value);
2197         }
2198       break;
2199     }
2200 }
2201
2202 // Do a relocation in which we convert a TLS General-Dynamic to a
2203 // Local-Exec.
2204
2205 inline void
2206 Target_i386::Relocate::tls_gd_to_le(const Relocate_info<32, false>* relinfo,
2207                                     size_t relnum,
2208                                     Output_segment* tls_segment,
2209                                     const elfcpp::Rel<32, false>& rel,
2210                                     unsigned int,
2211                                     elfcpp::Elf_types<32>::Elf_Addr value,
2212                                     unsigned char* view,
2213                                     section_size_type view_size)
2214 {
2215   // leal foo(,%reg,1),%eax; call ___tls_get_addr
2216   //  ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
2217   // leal foo(%reg),%eax; call ___tls_get_addr
2218   //  ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
2219
2220   tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
2221   tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 9);
2222
2223   unsigned char op1 = view[-1];
2224   unsigned char op2 = view[-2];
2225
2226   tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2227                  op2 == 0x8d || op2 == 0x04);
2228   tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[4] == 0xe8);
2229
2230   int roff = 5;
2231
2232   if (op2 == 0x04)
2233     {
2234       tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -3);
2235       tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[-3] == 0x8d);
2236       tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2237                      ((op1 & 0xc7) == 0x05 && op1 != (4 << 3)));
2238       memcpy(view - 3, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
2239     }
2240   else
2241     {
2242       tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2243                      (op1 & 0xf8) == 0x80 && (op1 & 7) != 4);
2244       if (rel.get_r_offset() + 9 < view_size
2245           && view[9] == 0x90)
2246         {
2247           // There is a trailing nop.  Use the size byte subl.
2248           memcpy(view - 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
2249           roff = 6;
2250         }
2251       else
2252         {
2253           // Use the five byte subl.
2254           memcpy(view - 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
2255         }
2256     }
2257
2258   value = tls_segment->memsz() - value;
2259   Relocate_functions<32, false>::rel32(view + roff, value);
2260
2261   // The next reloc should be a PLT32 reloc against __tls_get_addr.
2262   // We can skip it.
2263   this->skip_call_tls_get_addr_ = true;
2264 }
2265
2266 // Do a relocation in which we convert a TLS General-Dynamic to an
2267 // Initial-Exec.
2268
2269 inline void
2270 Target_i386::Relocate::tls_gd_to_ie(const Relocate_info<32, false>* relinfo,
2271                                     size_t relnum,
2272                                     Output_segment*,
2273                                     const elfcpp::Rel<32, false>& rel,
2274                                     unsigned int,
2275                                     elfcpp::Elf_types<32>::Elf_Addr value,
2276                                     unsigned char* view,
2277                                     section_size_type view_size)
2278 {
2279   // leal foo(,%ebx,1),%eax; call ___tls_get_addr
2280   //  ==> movl %gs:0,%eax; addl foo@gotntpoff(%ebx),%eax
2281
2282   tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
2283   tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 9);
2284
2285   unsigned char op1 = view[-1];
2286   unsigned char op2 = view[-2];
2287
2288   tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2289                  op2 == 0x8d || op2 == 0x04);
2290   tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[4] == 0xe8);
2291
2292   int roff = 5;
2293
2294   // FIXME: For now, support only the first (SIB) form.
2295   tls::check_tls(relinfo, relnum, rel.get_r_offset(), op2 == 0x04);
2296
2297   if (op2 == 0x04)
2298     {
2299       tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -3);
2300       tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[-3] == 0x8d);
2301       tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2302                      ((op1 & 0xc7) == 0x05 && op1 != (4 << 3)));
2303       memcpy(view - 3, "\x65\xa1\0\0\0\0\x03\x83\0\0\0", 12);
2304     }
2305   else
2306     {
2307       tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2308                      (op1 & 0xf8) == 0x80 && (op1 & 7) != 4);
2309       if (rel.get_r_offset() + 9 < view_size
2310           && view[9] == 0x90)
2311         {
2312           // FIXME: This is not the right instruction sequence.
2313           // There is a trailing nop.  Use the size byte subl.
2314           memcpy(view - 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
2315           roff = 6;
2316         }
2317       else
2318         {
2319           // FIXME: This is not the right instruction sequence.
2320           // Use the five byte subl.
2321           memcpy(view - 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
2322         }
2323     }
2324
2325   Relocate_functions<32, false>::rel32(view + roff, value);
2326
2327   // The next reloc should be a PLT32 reloc against __tls_get_addr.
2328   // We can skip it.
2329   this->skip_call_tls_get_addr_ = true;
2330 }
2331
2332 // Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL
2333 // General-Dynamic to a Local-Exec.
2334
2335 inline void
2336 Target_i386::Relocate::tls_desc_gd_to_le(
2337     const Relocate_info<32, false>* relinfo,
2338     size_t relnum,
2339     Output_segment* tls_segment,
2340     const elfcpp::Rel<32, false>& rel,
2341     unsigned int r_type,
2342     elfcpp::Elf_types<32>::Elf_Addr value,
2343     unsigned char* view,
2344     section_size_type view_size)
2345 {
2346   if (r_type == elfcpp::R_386_TLS_GOTDESC)
2347     {
2348       // leal foo@TLSDESC(%ebx), %eax
2349       // ==> leal foo@NTPOFF, %eax
2350       tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
2351       tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4);
2352       tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2353                      view[-2] == 0x8d && view[-1] == 0x83);
2354       view[-1] = 0x05;
2355       value -= tls_segment->memsz();
2356       Relocate_functions<32, false>::rel32(view, value);
2357     }
2358   else
2359     {
2360       // call *foo@TLSCALL(%eax)
2361       // ==> nop; nop
2362       gold_assert(r_type == elfcpp::R_386_TLS_DESC_CALL);
2363       tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 2);
2364       tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2365                      view[0] == 0xff && view[1] == 0x10);
2366       view[0] = 0x66;
2367       view[1] = 0x90;
2368     }
2369 }
2370
2371 // Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL
2372 // General-Dynamic to an Initial-Exec.
2373
2374 inline void
2375 Target_i386::Relocate::tls_desc_gd_to_ie(
2376     const Relocate_info<32, false>* relinfo,
2377     size_t relnum,
2378     Output_segment*,
2379     const elfcpp::Rel<32, false>& rel,
2380     unsigned int r_type,
2381     elfcpp::Elf_types<32>::Elf_Addr value,
2382     unsigned char* view,
2383     section_size_type view_size)
2384 {
2385   if (r_type == elfcpp::R_386_TLS_GOTDESC)
2386     {
2387       // leal foo@TLSDESC(%ebx), %eax
2388       // ==> movl foo@GOTNTPOFF(%ebx), %eax
2389       tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
2390       tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4);
2391       tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2392                      view[-2] == 0x8d && view[-1] == 0x83);
2393       view[-2] = 0x8b;
2394       Relocate_functions<32, false>::rel32(view, value);
2395     }
2396   else
2397     {
2398       // call *foo@TLSCALL(%eax)
2399       // ==> nop; nop
2400       gold_assert(r_type == elfcpp::R_386_TLS_DESC_CALL);
2401       tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 2);
2402       tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2403                      view[0] == 0xff && view[1] == 0x10);
2404       view[0] = 0x66;
2405       view[1] = 0x90;
2406     }
2407 }
2408
2409 // Do a relocation in which we convert a TLS Local-Dynamic to a
2410 // Local-Exec.
2411
2412 inline void
2413 Target_i386::Relocate::tls_ld_to_le(const Relocate_info<32, false>* relinfo,
2414                                     size_t relnum,
2415                                     Output_segment*,
2416                                     const elfcpp::Rel<32, false>& rel,
2417                                     unsigned int,
2418                                     elfcpp::Elf_types<32>::Elf_Addr,
2419                                     unsigned char* view,
2420                                     section_size_type view_size)
2421 {
2422   // leal foo(%reg), %eax; call ___tls_get_addr
2423   // ==> movl %gs:0,%eax; nop; leal 0(%esi,1),%esi
2424
2425   tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
2426   tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 9);
2427
2428   // FIXME: Does this test really always pass?
2429   tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2430                  view[-2] == 0x8d && view[-1] == 0x83);
2431
2432   tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[4] == 0xe8);
2433
2434   memcpy(view - 2, "\x65\xa1\0\0\0\0\x90\x8d\x74\x26\0", 11);
2435
2436   // The next reloc should be a PLT32 reloc against __tls_get_addr.
2437   // We can skip it.
2438   this->skip_call_tls_get_addr_ = true;
2439 }
2440
2441 // Do a relocation in which we convert a TLS Initial-Exec to a
2442 // Local-Exec.
2443
2444 inline void
2445 Target_i386::Relocate::tls_ie_to_le(const Relocate_info<32, false>* relinfo,
2446                                     size_t relnum,
2447                                     Output_segment* tls_segment,
2448                                     const elfcpp::Rel<32, false>& rel,
2449                                     unsigned int r_type,
2450                                     elfcpp::Elf_types<32>::Elf_Addr value,
2451                                     unsigned char* view,
2452                                     section_size_type view_size)
2453 {
2454   // We have to actually change the instructions, which means that we
2455   // need to examine the opcodes to figure out which instruction we
2456   // are looking at.
2457   if (r_type == elfcpp::R_386_TLS_IE)
2458     {
2459       // movl %gs:XX,%eax  ==>  movl $YY,%eax
2460       // movl %gs:XX,%reg  ==>  movl $YY,%reg
2461       // addl %gs:XX,%reg  ==>  addl $YY,%reg
2462       tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -1);
2463       tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4);
2464
2465       unsigned char op1 = view[-1];
2466       if (op1 == 0xa1)
2467         {
2468           // movl XX,%eax  ==>  movl $YY,%eax
2469           view[-1] = 0xb8;
2470         }
2471       else
2472         {
2473           tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
2474
2475           unsigned char op2 = view[-2];
2476           if (op2 == 0x8b)
2477             {
2478               // movl XX,%reg  ==>  movl $YY,%reg
2479               tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2480                              (op1 & 0xc7) == 0x05);
2481               view[-2] = 0xc7;
2482               view[-1] = 0xc0 | ((op1 >> 3) & 7);
2483             }
2484           else if (op2 == 0x03)
2485             {
2486               // addl XX,%reg  ==>  addl $YY,%reg
2487               tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2488                              (op1 & 0xc7) == 0x05);
2489               view[-2] = 0x81;
2490               view[-1] = 0xc0 | ((op1 >> 3) & 7);
2491             }
2492           else
2493             tls::check_tls(relinfo, relnum, rel.get_r_offset(), 0);
2494         }
2495     }
2496   else
2497     {
2498       // subl %gs:XX(%reg1),%reg2  ==>  subl $YY,%reg2
2499       // movl %gs:XX(%reg1),%reg2  ==>  movl $YY,%reg2
2500       // addl %gs:XX(%reg1),%reg2  ==>  addl $YY,$reg2
2501       tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
2502       tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4);
2503
2504       unsigned char op1 = view[-1];
2505       unsigned char op2 = view[-2];
2506       tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2507                      (op1 & 0xc0) == 0x80 && (op1 & 7) != 4);
2508       if (op2 == 0x8b)
2509         {
2510           // movl %gs:XX(%reg1),%reg2  ==>  movl $YY,%reg2
2511           view[-2] = 0xc7;
2512           view[-1] = 0xc0 | ((op1 >> 3) & 7);
2513         }
2514       else if (op2 == 0x2b)
2515         {
2516           // subl %gs:XX(%reg1),%reg2  ==>  subl $YY,%reg2
2517           view[-2] = 0x81;
2518           view[-1] = 0xe8 | ((op1 >> 3) & 7);
2519         }
2520       else if (op2 == 0x03)
2521         {
2522           // addl %gs:XX(%reg1),%reg2  ==>  addl $YY,$reg2
2523           view[-2] = 0x81;
2524           view[-1] = 0xc0 | ((op1 >> 3) & 7);
2525         }
2526       else
2527         tls::check_tls(relinfo, relnum, rel.get_r_offset(), 0);
2528     }
2529
2530   value = tls_segment->memsz() - value;
2531   if (r_type == elfcpp::R_386_TLS_IE || r_type == elfcpp::R_386_TLS_GOTIE)
2532     value = - value;
2533
2534   Relocate_functions<32, false>::rel32(view, value);
2535 }
2536
2537 // Relocate section data.
2538
2539 void
2540 Target_i386::relocate_section(const Relocate_info<32, false>* relinfo,
2541                               unsigned int sh_type,
2542                               const unsigned char* prelocs,
2543                               size_t reloc_count,
2544                               Output_section* output_section,
2545                               bool needs_special_offset_handling,
2546                               unsigned char* view,
2547                               elfcpp::Elf_types<32>::Elf_Addr address,
2548                               section_size_type view_size,
2549                               const Reloc_symbol_changes* reloc_symbol_changes)
2550 {
2551   gold_assert(sh_type == elfcpp::SHT_REL);
2552
2553   gold::relocate_section<32, false, Target_i386, elfcpp::SHT_REL,
2554                          Target_i386::Relocate>(
2555     relinfo,
2556     this,
2557     prelocs,
2558     reloc_count,
2559     output_section,
2560     needs_special_offset_handling,
2561     view,
2562     address,
2563     view_size,
2564     reloc_symbol_changes);
2565 }
2566
2567 // Return the size of a relocation while scanning during a relocatable
2568 // link.
2569
2570 unsigned int
2571 Target_i386::Relocatable_size_for_reloc::get_size_for_reloc(
2572     unsigned int r_type,
2573     Relobj* object)
2574 {
2575   switch (r_type)
2576     {
2577     case elfcpp::R_386_NONE:
2578     case elfcpp::R_386_GNU_VTINHERIT:
2579     case elfcpp::R_386_GNU_VTENTRY:
2580     case elfcpp::R_386_TLS_GD:            // Global-dynamic
2581     case elfcpp::R_386_TLS_GOTDESC:       // Global-dynamic (from ~oliva url)
2582     case elfcpp::R_386_TLS_DESC_CALL:
2583     case elfcpp::R_386_TLS_LDM:           // Local-dynamic
2584     case elfcpp::R_386_TLS_LDO_32:        // Alternate local-dynamic
2585     case elfcpp::R_386_TLS_IE:            // Initial-exec
2586     case elfcpp::R_386_TLS_IE_32:
2587     case elfcpp::R_386_TLS_GOTIE:
2588     case elfcpp::R_386_TLS_LE:            // Local-exec
2589     case elfcpp::R_386_TLS_LE_32:
2590       return 0;
2591
2592     case elfcpp::R_386_32:
2593     case elfcpp::R_386_PC32:
2594     case elfcpp::R_386_GOT32:
2595     case elfcpp::R_386_PLT32:
2596     case elfcpp::R_386_GOTOFF:
2597     case elfcpp::R_386_GOTPC:
2598      return 4;
2599
2600     case elfcpp::R_386_16:
2601     case elfcpp::R_386_PC16:
2602       return 2;
2603
2604     case elfcpp::R_386_8:
2605     case elfcpp::R_386_PC8:
2606       return 1;
2607
2608       // These are relocations which should only be seen by the
2609       // dynamic linker, and should never be seen here.
2610     case elfcpp::R_386_COPY:
2611     case elfcpp::R_386_GLOB_DAT:
2612     case elfcpp::R_386_JUMP_SLOT:
2613     case elfcpp::R_386_RELATIVE:
2614     case elfcpp::R_386_TLS_TPOFF:
2615     case elfcpp::R_386_TLS_DTPMOD32:
2616     case elfcpp::R_386_TLS_DTPOFF32:
2617     case elfcpp::R_386_TLS_TPOFF32:
2618     case elfcpp::R_386_TLS_DESC:
2619       object->error(_("unexpected reloc %u in object file"), r_type);
2620       return 0;
2621
2622     case elfcpp::R_386_32PLT:
2623     case elfcpp::R_386_TLS_GD_32:
2624     case elfcpp::R_386_TLS_GD_PUSH:
2625     case elfcpp::R_386_TLS_GD_CALL:
2626     case elfcpp::R_386_TLS_GD_POP:
2627     case elfcpp::R_386_TLS_LDM_32:
2628     case elfcpp::R_386_TLS_LDM_PUSH:
2629     case elfcpp::R_386_TLS_LDM_CALL:
2630     case elfcpp::R_386_TLS_LDM_POP:
2631     case elfcpp::R_386_USED_BY_INTEL_200:
2632     default:
2633       object->error(_("unsupported reloc %u in object file"), r_type);
2634       return 0;
2635     }
2636 }
2637
2638 // Scan the relocs during a relocatable link.
2639
2640 void
2641 Target_i386::scan_relocatable_relocs(Symbol_table* symtab,
2642                                      Layout* layout,
2643                                      Sized_relobj<32, false>* object,
2644                                      unsigned int data_shndx,
2645                                      unsigned int sh_type,
2646                                      const unsigned char* prelocs,
2647                                      size_t reloc_count,
2648                                      Output_section* output_section,
2649                                      bool needs_special_offset_handling,
2650                                      size_t local_symbol_count,
2651                                      const unsigned char* plocal_symbols,
2652                                      Relocatable_relocs* rr)
2653 {
2654   gold_assert(sh_type == elfcpp::SHT_REL);
2655
2656   typedef gold::Default_scan_relocatable_relocs<elfcpp::SHT_REL,
2657     Relocatable_size_for_reloc> Scan_relocatable_relocs;
2658
2659   gold::scan_relocatable_relocs<32, false, elfcpp::SHT_REL,
2660       Scan_relocatable_relocs>(
2661     symtab,
2662     layout,
2663     object,
2664     data_shndx,
2665     prelocs,
2666     reloc_count,
2667     output_section,
2668     needs_special_offset_handling,
2669     local_symbol_count,
2670     plocal_symbols,
2671     rr);
2672 }
2673
2674 // Relocate a section during a relocatable link.
2675
2676 void
2677 Target_i386::relocate_for_relocatable(
2678     const Relocate_info<32, false>* relinfo,
2679     unsigned int sh_type,
2680     const unsigned char* prelocs,
2681     size_t reloc_count,
2682     Output_section* output_section,
2683     off_t offset_in_output_section,
2684     const Relocatable_relocs* rr,
2685     unsigned char* view,
2686     elfcpp::Elf_types<32>::Elf_Addr view_address,
2687     section_size_type view_size,
2688     unsigned char* reloc_view,
2689     section_size_type reloc_view_size)
2690 {
2691   gold_assert(sh_type == elfcpp::SHT_REL);
2692
2693   gold::relocate_for_relocatable<32, false, elfcpp::SHT_REL>(
2694     relinfo,
2695     prelocs,
2696     reloc_count,
2697     output_section,
2698     offset_in_output_section,
2699     rr,
2700     view,
2701     view_address,
2702     view_size,
2703     reloc_view,
2704     reloc_view_size);
2705 }
2706
2707 // Return the value to use for a dynamic which requires special
2708 // treatment.  This is how we support equality comparisons of function
2709 // pointers across shared library boundaries, as described in the
2710 // processor specific ABI supplement.
2711
2712 uint64_t
2713 Target_i386::do_dynsym_value(const Symbol* gsym) const
2714 {
2715   gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset());
2716   return this->plt_section()->address() + gsym->plt_offset();
2717 }
2718
2719 // Return a string used to fill a code section with nops to take up
2720 // the specified length.
2721
2722 std::string
2723 Target_i386::do_code_fill(section_size_type length) const
2724 {
2725   if (length >= 16)
2726     {
2727       // Build a jmp instruction to skip over the bytes.
2728       unsigned char jmp[5];
2729       jmp[0] = 0xe9;
2730       elfcpp::Swap_unaligned<32, false>::writeval(jmp + 1, length - 5);
2731       return (std::string(reinterpret_cast<char*>(&jmp[0]), 5)
2732               + std::string(length - 5, '\0'));
2733     }
2734
2735   // Nop sequences of various lengths.
2736   const char nop1[1] = { 0x90 };                   // nop
2737   const char nop2[2] = { 0x66, 0x90 };             // xchg %ax %ax
2738   const char nop3[3] = { 0x8d, 0x76, 0x00 };       // leal 0(%esi),%esi
2739   const char nop4[4] = { 0x8d, 0x74, 0x26, 0x00};  // leal 0(%esi,1),%esi
2740   const char nop5[5] = { 0x90, 0x8d, 0x74, 0x26,   // nop
2741                          0x00 };                   // leal 0(%esi,1),%esi
2742   const char nop6[6] = { 0x8d, 0xb6, 0x00, 0x00,   // leal 0L(%esi),%esi
2743                          0x00, 0x00 };
2744   const char nop7[7] = { 0x8d, 0xb4, 0x26, 0x00,   // leal 0L(%esi,1),%esi
2745                          0x00, 0x00, 0x00 };
2746   const char nop8[8] = { 0x90, 0x8d, 0xb4, 0x26,   // nop
2747                          0x00, 0x00, 0x00, 0x00 }; // leal 0L(%esi,1),%esi
2748   const char nop9[9] = { 0x89, 0xf6, 0x8d, 0xbc,   // movl %esi,%esi
2749                          0x27, 0x00, 0x00, 0x00,   // leal 0L(%edi,1),%edi
2750                          0x00 };
2751   const char nop10[10] = { 0x8d, 0x76, 0x00, 0x8d, // leal 0(%esi),%esi
2752                            0xbc, 0x27, 0x00, 0x00, // leal 0L(%edi,1),%edi
2753                            0x00, 0x00 };
2754   const char nop11[11] = { 0x8d, 0x74, 0x26, 0x00, // leal 0(%esi,1),%esi
2755                            0x8d, 0xbc, 0x27, 0x00, // leal 0L(%edi,1),%edi
2756                            0x00, 0x00, 0x00 };
2757   const char nop12[12] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2758                            0x00, 0x00, 0x8d, 0xbf, // leal 0L(%edi),%edi
2759                            0x00, 0x00, 0x00, 0x00 };
2760   const char nop13[13] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2761                            0x00, 0x00, 0x8d, 0xbc, // leal 0L(%edi,1),%edi
2762                            0x27, 0x00, 0x00, 0x00,
2763                            0x00 };
2764   const char nop14[14] = { 0x8d, 0xb4, 0x26, 0x00, // leal 0L(%esi,1),%esi
2765                            0x00, 0x00, 0x00, 0x8d, // leal 0L(%edi,1),%edi
2766                            0xbc, 0x27, 0x00, 0x00,
2767                            0x00, 0x00 };
2768   const char nop15[15] = { 0xeb, 0x0d, 0x90, 0x90, // jmp .+15
2769                            0x90, 0x90, 0x90, 0x90, // nop,nop,nop,...
2770                            0x90, 0x90, 0x90, 0x90,
2771                            0x90, 0x90, 0x90 };
2772
2773   const char* nops[16] = {
2774     NULL,
2775     nop1, nop2, nop3, nop4, nop5, nop6, nop7,
2776     nop8, nop9, nop10, nop11, nop12, nop13, nop14, nop15
2777   };
2778
2779   return std::string(nops[length], length);
2780 }
2781
2782 // Return whether SYM should be treated as a call to a non-split
2783 // function.  We don't want that to be true of a call to a
2784 // get_pc_thunk function.
2785
2786 bool
2787 Target_i386::do_is_call_to_non_split(const Symbol* sym, unsigned int) const
2788 {
2789   return (sym->type() == elfcpp::STT_FUNC
2790           && !is_prefix_of("__i686.get_pc_thunk.", sym->name()));
2791 }
2792
2793 // FNOFFSET in section SHNDX in OBJECT is the start of a function
2794 // compiled with -fstack-split.  The function calls non-stack-split
2795 // code.  We have to change the function so that it always ensures
2796 // that it has enough stack space to run some random function.
2797
2798 void
2799 Target_i386::do_calls_non_split(Relobj* object, unsigned int shndx,
2800                                 section_offset_type fnoffset,
2801                                 section_size_type fnsize,
2802                                 unsigned char* view,
2803                                 section_size_type view_size,
2804                                 std::string* from,
2805                                 std::string* to) const
2806 {
2807   // The function starts with a comparison of the stack pointer and a
2808   // field in the TCB.  This is followed by a jump.
2809
2810   // cmp %gs:NN,%esp
2811   if (this->match_view(view, view_size, fnoffset, "\x65\x3b\x25", 3)
2812       && fnsize > 7)
2813     {
2814       // We will call __morestack if the carry flag is set after this
2815       // comparison.  We turn the comparison into an stc instruction
2816       // and some nops.
2817       view[fnoffset] = '\xf9';
2818       this->set_view_to_nop(view, view_size, fnoffset + 1, 6);
2819     }
2820   // lea NN(%esp),%ecx
2821   // lea NN(%esp),%edx
2822   else if ((this->match_view(view, view_size, fnoffset, "\x8d\x8c\x24", 3)
2823             || this->match_view(view, view_size, fnoffset, "\x8d\x94\x24", 3))
2824            && fnsize > 7)
2825     {
2826       // This is loading an offset from the stack pointer for a
2827       // comparison.  The offset is negative, so we decrease the
2828       // offset by the amount of space we need for the stack.  This
2829       // means we will avoid calling __morestack if there happens to
2830       // be plenty of space on the stack already.
2831       unsigned char* pval = view + fnoffset + 3;
2832       uint32_t val = elfcpp::Swap_unaligned<32, false>::readval(pval);
2833       val -= parameters->options().split_stack_adjust_size();
2834       elfcpp::Swap_unaligned<32, false>::writeval(pval, val);
2835     }
2836   else
2837     {
2838       if (!object->has_no_split_stack())
2839         object->error(_("failed to match split-stack sequence at "
2840                         "section %u offset %0zx"),
2841                       shndx, static_cast<size_t>(fnoffset));
2842       return;
2843     }
2844
2845   // We have to change the function so that it calls
2846   // __morestack_non_split instead of __morestack.  The former will
2847   // allocate additional stack space.
2848   *from = "__morestack";
2849   *to = "__morestack_non_split";
2850 }
2851
2852 // The selector for i386 object files.
2853
2854 class Target_selector_i386 : public Target_selector_freebsd
2855 {
2856 public:
2857   Target_selector_i386()
2858     : Target_selector_freebsd(elfcpp::EM_386, 32, false,
2859                               "elf32-i386", "elf32-i386-freebsd")
2860   { }
2861
2862   Target*
2863   do_instantiate_target()
2864   { return new Target_i386(); }
2865 };
2866
2867 Target_selector_i386 target_selector_i386;
2868
2869 } // End anonymous namespace.