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[pf3gnuchains/pf3gnuchains4x.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), rel_dyn_(NULL),
63       copy_relocs_(elfcpp::R_386_COPY), dynbss_(NULL),
64       got_mod_index_offset_(-1U), tls_base_symbol_defined_(false)
65   { }
66
67   // Process the relocations to determine unreferenced sections for 
68   // garbage collection.
69   void
70   gc_process_relocs(Symbol_table* symtab,
71                     Layout* layout,
72                     Sized_relobj<32, false>* object,
73                     unsigned int data_shndx,
74                     unsigned int sh_type,
75                     const unsigned char* prelocs,
76                     size_t reloc_count,
77                     Output_section* output_section,
78                     bool needs_special_offset_handling,
79                     size_t local_symbol_count,
80                     const unsigned char* plocal_symbols);
81
82   // Scan the relocations to look for symbol adjustments.
83   void
84   scan_relocs(Symbol_table* symtab,
85               Layout* layout,
86               Sized_relobj<32, false>* object,
87               unsigned int data_shndx,
88               unsigned int sh_type,
89               const unsigned char* prelocs,
90               size_t reloc_count,
91               Output_section* output_section,
92               bool needs_special_offset_handling,
93               size_t local_symbol_count,
94               const unsigned char* plocal_symbols);
95
96   // Finalize the sections.
97   void
98   do_finalize_sections(Layout*, const Input_objects*);
99
100   // Return the value to use for a dynamic which requires special
101   // treatment.
102   uint64_t
103   do_dynsym_value(const Symbol*) const;
104
105   // Relocate a section.
106   void
107   relocate_section(const Relocate_info<32, false>*,
108                    unsigned int sh_type,
109                    const unsigned char* prelocs,
110                    size_t reloc_count,
111                    Output_section* output_section,
112                    bool needs_special_offset_handling,
113                    unsigned char* view,
114                    elfcpp::Elf_types<32>::Elf_Addr view_address,
115                    section_size_type view_size,
116                    const Reloc_symbol_changes*);
117
118   // Scan the relocs during a relocatable link.
119   void
120   scan_relocatable_relocs(Symbol_table* symtab,
121                           Layout* layout,
122                           Sized_relobj<32, false>* object,
123                           unsigned int data_shndx,
124                           unsigned int sh_type,
125                           const unsigned char* prelocs,
126                           size_t reloc_count,
127                           Output_section* output_section,
128                           bool needs_special_offset_handling,
129                           size_t local_symbol_count,
130                           const unsigned char* plocal_symbols,
131                           Relocatable_relocs*);
132
133   // Relocate a section during a relocatable link.
134   void
135   relocate_for_relocatable(const Relocate_info<32, false>*,
136                            unsigned int sh_type,
137                            const unsigned char* prelocs,
138                            size_t reloc_count,
139                            Output_section* output_section,
140                            off_t offset_in_output_section,
141                            const Relocatable_relocs*,
142                            unsigned char* view,
143                            elfcpp::Elf_types<32>::Elf_Addr view_address,
144                            section_size_type view_size,
145                            unsigned char* reloc_view,
146                            section_size_type reloc_view_size);
147
148   // Return a string used to fill a code section with nops.
149   std::string
150   do_code_fill(section_size_type length) const;
151
152   // Return whether SYM is defined by the ABI.
153   bool
154   do_is_defined_by_abi(const Symbol* sym) const
155   { return strcmp(sym->name(), "___tls_get_addr") == 0; }
156
157   // Return whether a symbol name implies a local label.  The UnixWare
158   // 2.1 cc generates temporary symbols that start with .X, so we
159   // recognize them here.  FIXME: do other SVR4 compilers also use .X?.
160   // If so, we should move the .X recognition into
161   // Target::do_is_local_label_name.
162   bool
163   do_is_local_label_name(const char* name) const
164   {
165     if (name[0] == '.' && name[1] == 'X')
166       return true;
167     return Target::do_is_local_label_name(name);
168   }
169
170   // Adjust -fstack-split code which calls non-stack-split code.
171   void
172   do_calls_non_split(Relobj* object, unsigned int shndx,
173                      section_offset_type fnoffset, section_size_type fnsize,
174                      unsigned char* view, section_size_type view_size,
175                      std::string* from, std::string* to) const;
176
177   // Return the size of the GOT section.
178   section_size_type
179   got_size()
180   {
181     gold_assert(this->got_ != NULL);
182     return this->got_->data_size();
183   }
184
185  private:
186   // The class which scans relocations.
187   struct Scan
188   {
189     inline void
190     local(Symbol_table* symtab, Layout* layout, Target_i386* target,
191           Sized_relobj<32, false>* object,
192           unsigned int data_shndx,
193           Output_section* output_section,
194           const elfcpp::Rel<32, false>& reloc, unsigned int r_type,
195           const elfcpp::Sym<32, false>& lsym);
196
197     inline void
198     global(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            Symbol* gsym);
204
205     static void
206     unsupported_reloc_local(Sized_relobj<32, false>*, unsigned int r_type);
207
208     static void
209     unsupported_reloc_global(Sized_relobj<32, false>*, unsigned int r_type,
210                              Symbol*);
211   };
212
213   // The class which implements relocation.
214   class Relocate
215   {
216    public:
217     Relocate()
218       : skip_call_tls_get_addr_(false),
219         local_dynamic_type_(LOCAL_DYNAMIC_NONE)
220     { }
221
222     ~Relocate()
223     {
224       if (this->skip_call_tls_get_addr_)
225         {
226           // FIXME: This needs to specify the location somehow.
227           gold_error(_("missing expected TLS relocation"));
228         }
229     }
230
231     // Return whether the static relocation needs to be applied.
232     inline bool
233     should_apply_static_reloc(const Sized_symbol<32>* gsym,
234                               int ref_flags,
235                               bool is_32bit,
236                               Output_section* output_section);
237
238     // Do a relocation.  Return false if the caller should not issue
239     // any warnings about this relocation.
240     inline bool
241     relocate(const Relocate_info<32, false>*, Target_i386*, Output_section*,
242              size_t relnum, const elfcpp::Rel<32, false>&,
243              unsigned int r_type, const Sized_symbol<32>*,
244              const Symbol_value<32>*,
245              unsigned char*, elfcpp::Elf_types<32>::Elf_Addr,
246              section_size_type);
247
248    private:
249     // Do a TLS relocation.
250     inline void
251     relocate_tls(const Relocate_info<32, false>*, Target_i386* target,
252                  size_t relnum, const elfcpp::Rel<32, false>&,
253                  unsigned int r_type, const Sized_symbol<32>*,
254                  const Symbol_value<32>*,
255                  unsigned char*, elfcpp::Elf_types<32>::Elf_Addr,
256                  section_size_type);
257
258     // Do a TLS General-Dynamic to Initial-Exec transition.
259     inline void
260     tls_gd_to_ie(const Relocate_info<32, false>*, size_t relnum,
261                  Output_segment* tls_segment,
262                  const elfcpp::Rel<32, false>&, unsigned int r_type,
263                  elfcpp::Elf_types<32>::Elf_Addr value,
264                  unsigned char* view,
265                  section_size_type view_size);
266
267     // Do a TLS General-Dynamic to Local-Exec transition.
268     inline void
269     tls_gd_to_le(const Relocate_info<32, false>*, size_t relnum,
270                  Output_segment* tls_segment,
271                  const elfcpp::Rel<32, false>&, unsigned int r_type,
272                  elfcpp::Elf_types<32>::Elf_Addr value,
273                  unsigned char* view,
274                  section_size_type view_size);
275
276     // Do a TLS_GOTDESC or TLS_DESC_CALL General-Dynamic to Initial-Exec
277     // transition.
278     inline void
279     tls_desc_gd_to_ie(const Relocate_info<32, false>*, size_t relnum,
280                       Output_segment* tls_segment,
281                       const elfcpp::Rel<32, false>&, unsigned int r_type,
282                       elfcpp::Elf_types<32>::Elf_Addr value,
283                       unsigned char* view,
284                       section_size_type view_size);
285
286     // Do a TLS_GOTDESC or TLS_DESC_CALL General-Dynamic to Local-Exec
287     // transition.
288     inline void
289     tls_desc_gd_to_le(const Relocate_info<32, false>*, size_t relnum,
290                       Output_segment* tls_segment,
291                       const elfcpp::Rel<32, false>&, unsigned int r_type,
292                       elfcpp::Elf_types<32>::Elf_Addr value,
293                       unsigned char* view,
294                       section_size_type view_size);
295
296     // Do a TLS Local-Dynamic to Local-Exec transition.
297     inline void
298     tls_ld_to_le(const Relocate_info<32, false>*, size_t relnum,
299                  Output_segment* tls_segment,
300                  const elfcpp::Rel<32, false>&, unsigned int r_type,
301                  elfcpp::Elf_types<32>::Elf_Addr value,
302                  unsigned char* view,
303                  section_size_type view_size);
304
305     // Do a TLS Initial-Exec to Local-Exec transition.
306     static inline void
307     tls_ie_to_le(const Relocate_info<32, false>*, size_t relnum,
308                  Output_segment* tls_segment,
309                  const elfcpp::Rel<32, false>&, unsigned int r_type,
310                  elfcpp::Elf_types<32>::Elf_Addr value,
311                  unsigned char* view,
312                  section_size_type view_size);
313
314     // We need to keep track of which type of local dynamic relocation
315     // we have seen, so that we can optimize R_386_TLS_LDO_32 correctly.
316     enum Local_dynamic_type
317     {
318       LOCAL_DYNAMIC_NONE,
319       LOCAL_DYNAMIC_SUN,
320       LOCAL_DYNAMIC_GNU
321     };
322
323     // This is set if we should skip the next reloc, which should be a
324     // PLT32 reloc against ___tls_get_addr.
325     bool skip_call_tls_get_addr_;
326     // The type of local dynamic relocation we have seen in the section
327     // being relocated, if any.
328     Local_dynamic_type local_dynamic_type_;
329   };
330
331   // A class which returns the size required for a relocation type,
332   // used while scanning relocs during a relocatable link.
333   class Relocatable_size_for_reloc
334   {
335    public:
336     unsigned int
337     get_size_for_reloc(unsigned int, Relobj*);
338   };
339
340   // Adjust TLS relocation type based on the options and whether this
341   // is a local symbol.
342   static tls::Tls_optimization
343   optimize_tls_reloc(bool is_final, int r_type);
344
345   // Get the GOT section, creating it if necessary.
346   Output_data_got<32, false>*
347   got_section(Symbol_table*, Layout*);
348
349   // Get the GOT PLT section.
350   Output_data_space*
351   got_plt_section() const
352   {
353     gold_assert(this->got_plt_ != NULL);
354     return this->got_plt_;
355   }
356
357   // Create a PLT entry for a global symbol.
358   void
359   make_plt_entry(Symbol_table*, Layout*, Symbol*);
360
361   // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
362   void
363   define_tls_base_symbol(Symbol_table*, Layout*);
364
365   // Create a GOT entry for the TLS module index.
366   unsigned int
367   got_mod_index_entry(Symbol_table* symtab, Layout* layout,
368                       Sized_relobj<32, false>* object);
369
370   // Get the PLT section.
371   const Output_data_plt_i386*
372   plt_section() const
373   {
374     gold_assert(this->plt_ != NULL);
375     return this->plt_;
376   }
377
378   // Get the dynamic reloc section, creating it if necessary.
379   Reloc_section*
380   rel_dyn_section(Layout*);
381
382   // Add a potential copy relocation.
383   void
384   copy_reloc(Symbol_table* symtab, Layout* layout,
385              Sized_relobj<32, false>* object,
386              unsigned int shndx, Output_section* output_section,
387              Symbol* sym, const elfcpp::Rel<32, false>& reloc)
388   {
389     this->copy_relocs_.copy_reloc(symtab, layout,
390                                   symtab->get_sized_symbol<32>(sym),
391                                   object, shndx, output_section, reloc,
392                                   this->rel_dyn_section(layout));
393   }
394
395   // Information about this specific target which we pass to the
396   // general Target structure.
397   static const Target::Target_info i386_info;
398
399   // The types of GOT entries needed for this platform.
400   enum Got_type
401   {
402     GOT_TYPE_STANDARD = 0,      // GOT entry for a regular symbol
403     GOT_TYPE_TLS_NOFFSET = 1,   // GOT entry for negative TLS offset
404     GOT_TYPE_TLS_OFFSET = 2,    // GOT entry for positive TLS offset
405     GOT_TYPE_TLS_PAIR = 3,      // GOT entry for TLS module/offset pair
406     GOT_TYPE_TLS_DESC = 4       // GOT entry for TLS_DESC pair
407   };
408
409   // The GOT section.
410   Output_data_got<32, false>* got_;
411   // The PLT section.
412   Output_data_plt_i386* plt_;
413   // The GOT PLT section.
414   Output_data_space* got_plt_;
415   // The dynamic reloc section.
416   Reloc_section* rel_dyn_;
417   // Relocs saved to avoid a COPY reloc.
418   Copy_relocs<elfcpp::SHT_REL, 32, false> copy_relocs_;
419   // Space for variables copied with a COPY reloc.
420   Output_data_space* dynbss_;
421   // Offset of the GOT entry for the TLS module index.
422   unsigned int got_mod_index_offset_;
423   // True if the _TLS_MODULE_BASE_ symbol has been defined.
424   bool tls_base_symbol_defined_;
425 };
426
427 const Target::Target_info Target_i386::i386_info =
428 {
429   32,                   // size
430   false,                // is_big_endian
431   elfcpp::EM_386,       // machine_code
432   false,                // has_make_symbol
433   false,                // has_resolve
434   true,                 // has_code_fill
435   true,                 // is_default_stack_executable
436   '\0',                 // wrap_char
437   "/usr/lib/libc.so.1", // dynamic_linker
438   0x08048000,           // default_text_segment_address
439   0x1000,               // abi_pagesize (overridable by -z max-page-size)
440   0x1000,               // common_pagesize (overridable by -z common-page-size)
441   elfcpp::SHN_UNDEF,    // small_common_shndx
442   elfcpp::SHN_UNDEF,    // large_common_shndx
443   0,                    // small_common_section_flags
444   0                     // large_common_section_flags
445 };
446
447 // Get the GOT section, creating it if necessary.
448
449 Output_data_got<32, false>*
450 Target_i386::got_section(Symbol_table* symtab, Layout* layout)
451 {
452   if (this->got_ == NULL)
453     {
454       gold_assert(symtab != NULL && layout != NULL);
455
456       this->got_ = new Output_data_got<32, false>();
457
458       Output_section* os;
459       os = layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
460                                            (elfcpp::SHF_ALLOC
461                                             | elfcpp::SHF_WRITE),
462                                            this->got_, false);
463       os->set_is_relro();
464
465       // The old GNU linker creates a .got.plt section.  We just
466       // create another set of data in the .got section.  Note that we
467       // always create a PLT if we create a GOT, although the PLT
468       // might be empty.
469       this->got_plt_ = new Output_data_space(4, "** GOT PLT");
470       os = layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
471                                            (elfcpp::SHF_ALLOC
472                                             | elfcpp::SHF_WRITE),
473                                            this->got_plt_, false);
474       os->set_is_relro();
475
476       // The first three entries are reserved.
477       this->got_plt_->set_current_data_size(3 * 4);
478
479       // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
480       symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
481                                     this->got_plt_,
482                                     0, 0, elfcpp::STT_OBJECT,
483                                     elfcpp::STB_LOCAL,
484                                     elfcpp::STV_HIDDEN, 0,
485                                     false, false);
486     }
487
488   return this->got_;
489 }
490
491 // Get the dynamic reloc section, creating it if necessary.
492
493 Target_i386::Reloc_section*
494 Target_i386::rel_dyn_section(Layout* layout)
495 {
496   if (this->rel_dyn_ == NULL)
497     {
498       gold_assert(layout != NULL);
499       this->rel_dyn_ = new Reloc_section(parameters->options().combreloc());
500       layout->add_output_section_data(".rel.dyn", elfcpp::SHT_REL,
501                                       elfcpp::SHF_ALLOC, this->rel_dyn_, true);
502     }
503   return this->rel_dyn_;
504 }
505
506 // A class to handle the PLT data.
507
508 class Output_data_plt_i386 : public Output_section_data
509 {
510  public:
511   typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, false> Reloc_section;
512
513   Output_data_plt_i386(Layout*, Output_data_space*);
514
515   // Add an entry to the PLT.
516   void
517   add_entry(Symbol* gsym);
518
519   // Return the .rel.plt section data.
520   const Reloc_section*
521   rel_plt() const
522   { return this->rel_; }
523
524  protected:
525   void
526   do_adjust_output_section(Output_section* os);
527
528   // Write to a map file.
529   void
530   do_print_to_mapfile(Mapfile* mapfile) const
531   { mapfile->print_output_data(this, _("** PLT")); }
532
533  private:
534   // The size of an entry in the PLT.
535   static const int plt_entry_size = 16;
536
537   // The first entry in the PLT for an executable.
538   static unsigned char exec_first_plt_entry[plt_entry_size];
539
540   // The first entry in the PLT for a shared object.
541   static unsigned char dyn_first_plt_entry[plt_entry_size];
542
543   // Other entries in the PLT for an executable.
544   static unsigned char exec_plt_entry[plt_entry_size];
545
546   // Other entries in the PLT for a shared object.
547   static unsigned char dyn_plt_entry[plt_entry_size];
548
549   // Set the final size.
550   void
551   set_final_data_size()
552   { this->set_data_size((this->count_ + 1) * plt_entry_size); }
553
554   // Write out the PLT data.
555   void
556   do_write(Output_file*);
557
558   // The reloc section.
559   Reloc_section* rel_;
560   // The .got.plt section.
561   Output_data_space* got_plt_;
562   // The number of PLT entries.
563   unsigned int count_;
564 };
565
566 // Create the PLT section.  The ordinary .got section is an argument,
567 // since we need to refer to the start.  We also create our own .got
568 // section just for PLT entries.
569
570 Output_data_plt_i386::Output_data_plt_i386(Layout* layout,
571                                            Output_data_space* got_plt)
572   : Output_section_data(4), got_plt_(got_plt), count_(0)
573 {
574   this->rel_ = new Reloc_section(false);
575   layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL,
576                                   elfcpp::SHF_ALLOC, this->rel_, true);
577 }
578
579 void
580 Output_data_plt_i386::do_adjust_output_section(Output_section* os)
581 {
582   // UnixWare sets the entsize of .plt to 4, and so does the old GNU
583   // linker, and so do we.
584   os->set_entsize(4);
585 }
586
587 // Add an entry to the PLT.
588
589 void
590 Output_data_plt_i386::add_entry(Symbol* gsym)
591 {
592   gold_assert(!gsym->has_plt_offset());
593
594   // Note that when setting the PLT offset we skip the initial
595   // reserved PLT entry.
596   gsym->set_plt_offset((this->count_ + 1) * plt_entry_size);
597
598   ++this->count_;
599
600   section_offset_type got_offset = this->got_plt_->current_data_size();
601
602   // Every PLT entry needs a GOT entry which points back to the PLT
603   // entry (this will be changed by the dynamic linker, normally
604   // lazily when the function is called).
605   this->got_plt_->set_current_data_size(got_offset + 4);
606
607   // Every PLT entry needs a reloc.
608   gsym->set_needs_dynsym_entry();
609   this->rel_->add_global(gsym, elfcpp::R_386_JUMP_SLOT, this->got_plt_,
610                          got_offset);
611
612   // Note that we don't need to save the symbol.  The contents of the
613   // PLT are independent of which symbols are used.  The symbols only
614   // appear in the relocations.
615 }
616
617 // The first entry in the PLT for an executable.
618
619 unsigned char Output_data_plt_i386::exec_first_plt_entry[plt_entry_size] =
620 {
621   0xff, 0x35,   // pushl contents of memory address
622   0, 0, 0, 0,   // replaced with address of .got + 4
623   0xff, 0x25,   // jmp indirect
624   0, 0, 0, 0,   // replaced with address of .got + 8
625   0, 0, 0, 0    // unused
626 };
627
628 // The first entry in the PLT for a shared object.
629
630 unsigned char Output_data_plt_i386::dyn_first_plt_entry[plt_entry_size] =
631 {
632   0xff, 0xb3, 4, 0, 0, 0,       // pushl 4(%ebx)
633   0xff, 0xa3, 8, 0, 0, 0,       // jmp *8(%ebx)
634   0, 0, 0, 0                    // unused
635 };
636
637 // Subsequent entries in the PLT for an executable.
638
639 unsigned char Output_data_plt_i386::exec_plt_entry[plt_entry_size] =
640 {
641   0xff, 0x25,   // jmp indirect
642   0, 0, 0, 0,   // replaced with address of symbol in .got
643   0x68,         // pushl immediate
644   0, 0, 0, 0,   // replaced with offset into relocation table
645   0xe9,         // jmp relative
646   0, 0, 0, 0    // replaced with offset to start of .plt
647 };
648
649 // Subsequent entries in the PLT for a shared object.
650
651 unsigned char Output_data_plt_i386::dyn_plt_entry[plt_entry_size] =
652 {
653   0xff, 0xa3,   // jmp *offset(%ebx)
654   0, 0, 0, 0,   // replaced with offset of symbol in .got
655   0x68,         // pushl immediate
656   0, 0, 0, 0,   // replaced with offset into relocation table
657   0xe9,         // jmp relative
658   0, 0, 0, 0    // replaced with offset to start of .plt
659 };
660
661 // Write out the PLT.  This uses the hand-coded instructions above,
662 // and adjusts them as needed.  This is all specified by the i386 ELF
663 // Processor Supplement.
664
665 void
666 Output_data_plt_i386::do_write(Output_file* of)
667 {
668   const off_t offset = this->offset();
669   const section_size_type oview_size =
670     convert_to_section_size_type(this->data_size());
671   unsigned char* const oview = of->get_output_view(offset, oview_size);
672
673   const off_t got_file_offset = this->got_plt_->offset();
674   const section_size_type got_size =
675     convert_to_section_size_type(this->got_plt_->data_size());
676   unsigned char* const got_view = of->get_output_view(got_file_offset,
677                                                       got_size);
678
679   unsigned char* pov = oview;
680
681   elfcpp::Elf_types<32>::Elf_Addr plt_address = this->address();
682   elfcpp::Elf_types<32>::Elf_Addr got_address = this->got_plt_->address();
683
684   if (parameters->options().output_is_position_independent())
685     memcpy(pov, dyn_first_plt_entry, plt_entry_size);
686   else
687     {
688       memcpy(pov, exec_first_plt_entry, plt_entry_size);
689       elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_address + 4);
690       elfcpp::Swap<32, false>::writeval(pov + 8, got_address + 8);
691     }
692   pov += plt_entry_size;
693
694   unsigned char* got_pov = got_view;
695
696   memset(got_pov, 0, 12);
697   got_pov += 12;
698
699   const int rel_size = elfcpp::Elf_sizes<32>::rel_size;
700
701   unsigned int plt_offset = plt_entry_size;
702   unsigned int plt_rel_offset = 0;
703   unsigned int got_offset = 12;
704   const unsigned int count = this->count_;
705   for (unsigned int i = 0;
706        i < count;
707        ++i,
708          pov += plt_entry_size,
709          got_pov += 4,
710          plt_offset += plt_entry_size,
711          plt_rel_offset += rel_size,
712          got_offset += 4)
713     {
714       // Set and adjust the PLT entry itself.
715
716       if (parameters->options().output_is_position_independent())
717         {
718           memcpy(pov, dyn_plt_entry, plt_entry_size);
719           elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_offset);
720         }
721       else
722         {
723           memcpy(pov, exec_plt_entry, plt_entry_size);
724           elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
725                                                       (got_address
726                                                        + got_offset));
727         }
728
729       elfcpp::Swap_unaligned<32, false>::writeval(pov + 7, plt_rel_offset);
730       elfcpp::Swap<32, false>::writeval(pov + 12,
731                                         - (plt_offset + plt_entry_size));
732
733       // Set the entry in the GOT.
734       elfcpp::Swap<32, false>::writeval(got_pov, plt_address + plt_offset + 6);
735     }
736
737   gold_assert(static_cast<section_size_type>(pov - oview) == oview_size);
738   gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size);
739
740   of->write_output_view(offset, oview_size, oview);
741   of->write_output_view(got_file_offset, got_size, got_view);
742 }
743
744 // Create a PLT entry for a global symbol.
745
746 void
747 Target_i386::make_plt_entry(Symbol_table* symtab, Layout* layout, Symbol* gsym)
748 {
749   if (gsym->has_plt_offset())
750     return;
751
752   if (this->plt_ == NULL)
753     {
754       // Create the GOT sections first.
755       this->got_section(symtab, layout);
756
757       this->plt_ = new Output_data_plt_i386(layout, this->got_plt_);
758       layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
759                                       (elfcpp::SHF_ALLOC
760                                        | elfcpp::SHF_EXECINSTR),
761                                       this->plt_, false);
762     }
763
764   this->plt_->add_entry(gsym);
765 }
766
767 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
768
769 void
770 Target_i386::define_tls_base_symbol(Symbol_table* symtab, Layout* layout)
771 {
772   if (this->tls_base_symbol_defined_)
773     return;
774
775   Output_segment* tls_segment = layout->tls_segment();
776   if (tls_segment != NULL)
777     {
778       bool is_exec = parameters->options().output_is_executable();
779       symtab->define_in_output_segment("_TLS_MODULE_BASE_", NULL,
780                                        tls_segment, 0, 0,
781                                        elfcpp::STT_TLS,
782                                        elfcpp::STB_LOCAL,
783                                        elfcpp::STV_HIDDEN, 0,
784                                        (is_exec
785                                         ? Symbol::SEGMENT_END
786                                         : Symbol::SEGMENT_START),
787                                        true);
788     }
789   this->tls_base_symbol_defined_ = true;
790 }
791
792 // Create a GOT entry for the TLS module index.
793
794 unsigned int
795 Target_i386::got_mod_index_entry(Symbol_table* symtab, Layout* layout,
796                                  Sized_relobj<32, false>* object)
797 {
798   if (this->got_mod_index_offset_ == -1U)
799     {
800       gold_assert(symtab != NULL && layout != NULL && object != NULL);
801       Reloc_section* rel_dyn = this->rel_dyn_section(layout);
802       Output_data_got<32, false>* got = this->got_section(symtab, layout);
803       unsigned int got_offset = got->add_constant(0);
804       rel_dyn->add_local(object, 0, elfcpp::R_386_TLS_DTPMOD32, got,
805                          got_offset);
806       got->add_constant(0);
807       this->got_mod_index_offset_ = got_offset;
808     }
809   return this->got_mod_index_offset_;
810 }
811
812 // Optimize the TLS relocation type based on what we know about the
813 // symbol.  IS_FINAL is true if the final address of this symbol is
814 // known at link time.
815
816 tls::Tls_optimization
817 Target_i386::optimize_tls_reloc(bool is_final, int r_type)
818 {
819   // If we are generating a shared library, then we can't do anything
820   // in the linker.
821   if (parameters->options().shared())
822     return tls::TLSOPT_NONE;
823
824   switch (r_type)
825     {
826     case elfcpp::R_386_TLS_GD:
827     case elfcpp::R_386_TLS_GOTDESC:
828     case elfcpp::R_386_TLS_DESC_CALL:
829       // These are General-Dynamic which permits fully general TLS
830       // access.  Since we know that we are generating an executable,
831       // we can convert this to Initial-Exec.  If we also know that
832       // this is a local symbol, we can further switch to Local-Exec.
833       if (is_final)
834         return tls::TLSOPT_TO_LE;
835       return tls::TLSOPT_TO_IE;
836
837     case elfcpp::R_386_TLS_LDM:
838       // This is Local-Dynamic, which refers to a local symbol in the
839       // dynamic TLS block.  Since we know that we generating an
840       // executable, we can switch to Local-Exec.
841       return tls::TLSOPT_TO_LE;
842
843     case elfcpp::R_386_TLS_LDO_32:
844       // Another type of Local-Dynamic relocation.
845       return tls::TLSOPT_TO_LE;
846
847     case elfcpp::R_386_TLS_IE:
848     case elfcpp::R_386_TLS_GOTIE:
849     case elfcpp::R_386_TLS_IE_32:
850       // These are Initial-Exec relocs which get the thread offset
851       // from the GOT.  If we know that we are linking against the
852       // local symbol, we can switch to Local-Exec, which links the
853       // thread offset into the instruction.
854       if (is_final)
855         return tls::TLSOPT_TO_LE;
856       return tls::TLSOPT_NONE;
857
858     case elfcpp::R_386_TLS_LE:
859     case elfcpp::R_386_TLS_LE_32:
860       // When we already have Local-Exec, there is nothing further we
861       // can do.
862       return tls::TLSOPT_NONE;
863
864     default:
865       gold_unreachable();
866     }
867 }
868
869 // Report an unsupported relocation against a local symbol.
870
871 void
872 Target_i386::Scan::unsupported_reloc_local(Sized_relobj<32, false>* object,
873                                            unsigned int r_type)
874 {
875   gold_error(_("%s: unsupported reloc %u against local symbol"),
876              object->name().c_str(), r_type);
877 }
878
879 // Scan a relocation for a local symbol.
880
881 inline void
882 Target_i386::Scan::local(Symbol_table* symtab,
883                          Layout* layout,
884                          Target_i386* target,
885                          Sized_relobj<32, false>* object,
886                          unsigned int data_shndx,
887                          Output_section* output_section,
888                          const elfcpp::Rel<32, false>& reloc,
889                          unsigned int r_type,
890                          const elfcpp::Sym<32, false>& lsym)
891 {
892   switch (r_type)
893     {
894     case elfcpp::R_386_NONE:
895     case elfcpp::R_386_GNU_VTINHERIT:
896     case elfcpp::R_386_GNU_VTENTRY:
897       break;
898
899     case elfcpp::R_386_32:
900       // If building a shared library (or a position-independent
901       // executable), we need to create a dynamic relocation for
902       // this location. The relocation applied at link time will
903       // apply the link-time value, so we flag the location with
904       // an R_386_RELATIVE relocation so the dynamic loader can
905       // relocate it easily.
906       if (parameters->options().output_is_position_independent())
907         {
908           Reloc_section* rel_dyn = target->rel_dyn_section(layout);
909           unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
910           rel_dyn->add_local_relative(object, r_sym, elfcpp::R_386_RELATIVE,
911                                       output_section, data_shndx,
912                                       reloc.get_r_offset());
913         }
914       break;
915
916     case elfcpp::R_386_16:
917     case elfcpp::R_386_8:
918       // If building a shared library (or a position-independent
919       // executable), we need to create a dynamic relocation for
920       // this location. Because the addend needs to remain in the
921       // data section, we need to be careful not to apply this
922       // relocation statically.
923       if (parameters->options().output_is_position_independent())
924         {
925           Reloc_section* rel_dyn = target->rel_dyn_section(layout);
926           unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
927           if (lsym.get_st_type() != elfcpp::STT_SECTION)
928             rel_dyn->add_local(object, r_sym, r_type, output_section,
929                                data_shndx, reloc.get_r_offset());
930           else
931             {
932               gold_assert(lsym.get_st_value() == 0);
933               unsigned int shndx = lsym.get_st_shndx();
934               bool is_ordinary;
935               shndx = object->adjust_sym_shndx(r_sym, shndx,
936                                                &is_ordinary);
937               if (!is_ordinary)
938                 object->error(_("section symbol %u has bad shndx %u"),
939                               r_sym, shndx);
940               else
941                 rel_dyn->add_local_section(object, shndx,
942                                            r_type, output_section,
943                                            data_shndx, reloc.get_r_offset());
944             }
945         }
946       break;
947
948     case elfcpp::R_386_PC32:
949     case elfcpp::R_386_PC16:
950     case elfcpp::R_386_PC8:
951       break;
952
953     case elfcpp::R_386_PLT32:
954       // Since we know this is a local symbol, we can handle this as a
955       // PC32 reloc.
956       break;
957
958     case elfcpp::R_386_GOTOFF:
959     case elfcpp::R_386_GOTPC:
960       // We need a GOT section.
961       target->got_section(symtab, layout);
962       break;
963
964     case elfcpp::R_386_GOT32:
965       {
966         // The symbol requires a GOT entry.
967         Output_data_got<32, false>* got = target->got_section(symtab, layout);
968         unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
969         if (got->add_local(object, r_sym, GOT_TYPE_STANDARD))
970           {
971             // If we are generating a shared object, we need to add a
972             // dynamic RELATIVE relocation for this symbol's GOT entry.
973             if (parameters->options().output_is_position_independent())
974               {
975                 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
976                 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
977                 rel_dyn->add_local_relative(
978                     object, r_sym, elfcpp::R_386_RELATIVE, got,
979                     object->local_got_offset(r_sym, GOT_TYPE_STANDARD));
980               }
981           }
982       }
983       break;
984
985       // These are relocations which should only be seen by the
986       // dynamic linker, and should never be seen here.
987     case elfcpp::R_386_COPY:
988     case elfcpp::R_386_GLOB_DAT:
989     case elfcpp::R_386_JUMP_SLOT:
990     case elfcpp::R_386_RELATIVE:
991     case elfcpp::R_386_TLS_TPOFF:
992     case elfcpp::R_386_TLS_DTPMOD32:
993     case elfcpp::R_386_TLS_DTPOFF32:
994     case elfcpp::R_386_TLS_TPOFF32:
995     case elfcpp::R_386_TLS_DESC:
996       gold_error(_("%s: unexpected reloc %u in object file"),
997                  object->name().c_str(), r_type);
998       break;
999
1000       // These are initial TLS relocs, which are expected when
1001       // linking.
1002     case elfcpp::R_386_TLS_GD:            // Global-dynamic
1003     case elfcpp::R_386_TLS_GOTDESC:       // Global-dynamic (from ~oliva url)
1004     case elfcpp::R_386_TLS_DESC_CALL:
1005     case elfcpp::R_386_TLS_LDM:           // Local-dynamic
1006     case elfcpp::R_386_TLS_LDO_32:        // Alternate local-dynamic
1007     case elfcpp::R_386_TLS_IE:            // Initial-exec
1008     case elfcpp::R_386_TLS_IE_32:
1009     case elfcpp::R_386_TLS_GOTIE:
1010     case elfcpp::R_386_TLS_LE:            // Local-exec
1011     case elfcpp::R_386_TLS_LE_32:
1012       {
1013         bool output_is_shared = parameters->options().shared();
1014         const tls::Tls_optimization optimized_type
1015             = Target_i386::optimize_tls_reloc(!output_is_shared, r_type);
1016         switch (r_type)
1017           {
1018           case elfcpp::R_386_TLS_GD:          // Global-dynamic
1019             if (optimized_type == tls::TLSOPT_NONE)
1020               {
1021                 // Create a pair of GOT entries for the module index and
1022                 // dtv-relative offset.
1023                 Output_data_got<32, false>* got
1024                     = target->got_section(symtab, layout);
1025                 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1026                 unsigned int shndx = lsym.get_st_shndx();
1027                 bool is_ordinary;
1028                 shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
1029                 if (!is_ordinary)
1030                   object->error(_("local symbol %u has bad shndx %u"),
1031                               r_sym, shndx);
1032                 else
1033                   got->add_local_pair_with_rel(object, r_sym, shndx,
1034                                                GOT_TYPE_TLS_PAIR,
1035                                                target->rel_dyn_section(layout),
1036                                                elfcpp::R_386_TLS_DTPMOD32, 0);
1037               }
1038             else if (optimized_type != tls::TLSOPT_TO_LE)
1039               unsupported_reloc_local(object, r_type);
1040             break;
1041
1042           case elfcpp::R_386_TLS_GOTDESC:     // Global-dynamic (from ~oliva)
1043             target->define_tls_base_symbol(symtab, layout);
1044             if (optimized_type == tls::TLSOPT_NONE)
1045               {
1046                 // Create a double GOT entry with an R_386_TLS_DESC reloc.
1047                 Output_data_got<32, false>* got
1048                     = target->got_section(symtab, layout);
1049                 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1050                 unsigned int shndx = lsym.get_st_shndx();
1051                 bool is_ordinary;
1052                 shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
1053                 if (!is_ordinary)
1054                   object->error(_("local symbol %u has bad shndx %u"),
1055                               r_sym, shndx);
1056                 else
1057                   got->add_local_pair_with_rel(object, r_sym, shndx,
1058                                                GOT_TYPE_TLS_DESC,
1059                                                target->rel_dyn_section(layout),
1060                                                elfcpp::R_386_TLS_DESC, 0);
1061               }
1062             else if (optimized_type != tls::TLSOPT_TO_LE)
1063               unsupported_reloc_local(object, r_type);
1064             break;
1065
1066           case elfcpp::R_386_TLS_DESC_CALL:
1067             break;
1068
1069           case elfcpp::R_386_TLS_LDM:         // Local-dynamic
1070             if (optimized_type == tls::TLSOPT_NONE)
1071               {
1072                 // Create a GOT entry for the module index.
1073                 target->got_mod_index_entry(symtab, layout, object);
1074               }
1075             else if (optimized_type != tls::TLSOPT_TO_LE)
1076               unsupported_reloc_local(object, r_type);
1077             break;
1078
1079           case elfcpp::R_386_TLS_LDO_32:      // Alternate local-dynamic
1080             break;
1081
1082           case elfcpp::R_386_TLS_IE:          // Initial-exec
1083           case elfcpp::R_386_TLS_IE_32:
1084           case elfcpp::R_386_TLS_GOTIE:
1085             layout->set_has_static_tls();
1086             if (optimized_type == tls::TLSOPT_NONE)
1087               {
1088                 // For the R_386_TLS_IE relocation, we need to create a
1089                 // dynamic relocation when building a shared library.
1090                 if (r_type == elfcpp::R_386_TLS_IE
1091                     && parameters->options().shared())
1092                   {
1093                     Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1094                     unsigned int r_sym
1095                         = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1096                     rel_dyn->add_local_relative(object, r_sym,
1097                                                 elfcpp::R_386_RELATIVE,
1098                                                 output_section, data_shndx,
1099                                                 reloc.get_r_offset());
1100                   }
1101                 // Create a GOT entry for the tp-relative offset.
1102                 Output_data_got<32, false>* got
1103                     = target->got_section(symtab, layout);
1104                 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1105                 unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_IE_32
1106                                            ? elfcpp::R_386_TLS_TPOFF32
1107                                            : elfcpp::R_386_TLS_TPOFF);
1108                 unsigned int got_type = (r_type == elfcpp::R_386_TLS_IE_32
1109                                          ? GOT_TYPE_TLS_OFFSET
1110                                          : GOT_TYPE_TLS_NOFFSET);
1111                 got->add_local_with_rel(object, r_sym, got_type,
1112                                         target->rel_dyn_section(layout),
1113                                         dyn_r_type);
1114               }
1115             else if (optimized_type != tls::TLSOPT_TO_LE)
1116               unsupported_reloc_local(object, r_type);
1117             break;
1118
1119           case elfcpp::R_386_TLS_LE:          // Local-exec
1120           case elfcpp::R_386_TLS_LE_32:
1121             layout->set_has_static_tls();
1122             if (output_is_shared)
1123               {
1124                 // We need to create a dynamic relocation.
1125                 gold_assert(lsym.get_st_type() != elfcpp::STT_SECTION);
1126                 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1127                 unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_LE_32
1128                                            ? elfcpp::R_386_TLS_TPOFF32
1129                                            : elfcpp::R_386_TLS_TPOFF);
1130                 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1131                 rel_dyn->add_local(object, r_sym, dyn_r_type, output_section,
1132                                    data_shndx, reloc.get_r_offset());
1133               }
1134             break;
1135
1136           default:
1137             gold_unreachable();
1138           }
1139       }
1140       break;
1141
1142     case elfcpp::R_386_32PLT:
1143     case elfcpp::R_386_TLS_GD_32:
1144     case elfcpp::R_386_TLS_GD_PUSH:
1145     case elfcpp::R_386_TLS_GD_CALL:
1146     case elfcpp::R_386_TLS_GD_POP:
1147     case elfcpp::R_386_TLS_LDM_32:
1148     case elfcpp::R_386_TLS_LDM_PUSH:
1149     case elfcpp::R_386_TLS_LDM_CALL:
1150     case elfcpp::R_386_TLS_LDM_POP:
1151     case elfcpp::R_386_USED_BY_INTEL_200:
1152     default:
1153       unsupported_reloc_local(object, r_type);
1154       break;
1155     }
1156 }
1157
1158 // Report an unsupported relocation against a global symbol.
1159
1160 void
1161 Target_i386::Scan::unsupported_reloc_global(Sized_relobj<32, false>* object,
1162                                             unsigned int r_type,
1163                                             Symbol* gsym)
1164 {
1165   gold_error(_("%s: unsupported reloc %u against global symbol %s"),
1166              object->name().c_str(), r_type, gsym->demangled_name().c_str());
1167 }
1168
1169 // Scan a relocation for a global symbol.
1170
1171 inline void
1172 Target_i386::Scan::global(Symbol_table* symtab,
1173                           Layout* layout,
1174                           Target_i386* target,
1175                           Sized_relobj<32, false>* object,
1176                           unsigned int data_shndx,
1177                           Output_section* output_section,
1178                           const elfcpp::Rel<32, false>& reloc,
1179                           unsigned int r_type,
1180                           Symbol* gsym)
1181 {
1182   switch (r_type)
1183     {
1184     case elfcpp::R_386_NONE:
1185     case elfcpp::R_386_GNU_VTINHERIT:
1186     case elfcpp::R_386_GNU_VTENTRY:
1187       break;
1188
1189     case elfcpp::R_386_32:
1190     case elfcpp::R_386_16:
1191     case elfcpp::R_386_8:
1192       {
1193         // Make a PLT entry if necessary.
1194         if (gsym->needs_plt_entry())
1195           {
1196             target->make_plt_entry(symtab, layout, gsym);
1197             // Since this is not a PC-relative relocation, we may be
1198             // taking the address of a function. In that case we need to
1199             // set the entry in the dynamic symbol table to the address of
1200             // the PLT entry.
1201             if (gsym->is_from_dynobj() && !parameters->options().shared())
1202               gsym->set_needs_dynsym_value();
1203           }
1204         // Make a dynamic relocation if necessary.
1205         if (gsym->needs_dynamic_reloc(Symbol::ABSOLUTE_REF))
1206           {
1207             if (gsym->may_need_copy_reloc())
1208               {
1209                 target->copy_reloc(symtab, layout, object,
1210                                    data_shndx, output_section, gsym, reloc);
1211               }
1212             else if (r_type == elfcpp::R_386_32
1213                      && gsym->can_use_relative_reloc(false))
1214               {
1215                 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1216                 rel_dyn->add_global_relative(gsym, elfcpp::R_386_RELATIVE,
1217                                              output_section, object,
1218                                              data_shndx, reloc.get_r_offset());
1219               }
1220             else
1221               {
1222                 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1223                 rel_dyn->add_global(gsym, r_type, output_section, object,
1224                                     data_shndx, reloc.get_r_offset());
1225               }
1226           }
1227       }
1228       break;
1229
1230     case elfcpp::R_386_PC32:
1231     case elfcpp::R_386_PC16:
1232     case elfcpp::R_386_PC8:
1233       {
1234         // Make a PLT entry if necessary.
1235         if (gsym->needs_plt_entry())
1236           {
1237             // These relocations are used for function calls only in
1238             // non-PIC code.  For a 32-bit relocation in a shared library,
1239             // we'll need a text relocation anyway, so we can skip the
1240             // PLT entry and let the dynamic linker bind the call directly
1241             // to the target.  For smaller relocations, we should use a
1242             // PLT entry to ensure that the call can reach.
1243             if (!parameters->options().shared()
1244                 || r_type != elfcpp::R_386_PC32)
1245               target->make_plt_entry(symtab, layout, gsym);
1246           }
1247         // Make a dynamic relocation if necessary.
1248         int flags = Symbol::NON_PIC_REF;
1249         if (gsym->type() == elfcpp::STT_FUNC)
1250           flags |= Symbol::FUNCTION_CALL;
1251         if (gsym->needs_dynamic_reloc(flags))
1252           {
1253             if (gsym->may_need_copy_reloc())
1254               {
1255                 target->copy_reloc(symtab, layout, object,
1256                                    data_shndx, output_section, gsym, reloc);
1257               }
1258             else
1259               {
1260                 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1261                 rel_dyn->add_global(gsym, r_type, output_section, object,
1262                                     data_shndx, reloc.get_r_offset());
1263               }
1264           }
1265       }
1266       break;
1267
1268     case elfcpp::R_386_GOT32:
1269       {
1270         // The symbol requires a GOT entry.
1271         Output_data_got<32, false>* got = target->got_section(symtab, layout);
1272         if (gsym->final_value_is_known())
1273           got->add_global(gsym, GOT_TYPE_STANDARD);
1274         else
1275           {
1276             // If this symbol is not fully resolved, we need to add a
1277             // GOT entry with a dynamic relocation.
1278             Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1279             if (gsym->is_from_dynobj()
1280                 || gsym->is_undefined()
1281                 || gsym->is_preemptible())
1282               got->add_global_with_rel(gsym, GOT_TYPE_STANDARD,
1283                                        rel_dyn, elfcpp::R_386_GLOB_DAT);
1284             else
1285               {
1286                 if (got->add_global(gsym, GOT_TYPE_STANDARD))
1287                   rel_dyn->add_global_relative(
1288                       gsym, elfcpp::R_386_RELATIVE, got,
1289                       gsym->got_offset(GOT_TYPE_STANDARD));
1290               }
1291           }
1292       }
1293       break;
1294
1295     case elfcpp::R_386_PLT32:
1296       // If the symbol is fully resolved, this is just a PC32 reloc.
1297       // Otherwise we need a PLT entry.
1298       if (gsym->final_value_is_known())
1299         break;
1300       // If building a shared library, we can also skip the PLT entry
1301       // if the symbol is defined in the output file and is protected
1302       // or hidden.
1303       if (gsym->is_defined()
1304           && !gsym->is_from_dynobj()
1305           && !gsym->is_preemptible())
1306         break;
1307       target->make_plt_entry(symtab, layout, gsym);
1308       break;
1309
1310     case elfcpp::R_386_GOTOFF:
1311     case elfcpp::R_386_GOTPC:
1312       // We need a GOT section.
1313       target->got_section(symtab, layout);
1314       break;
1315
1316       // These are relocations which should only be seen by the
1317       // dynamic linker, and should never be seen here.
1318     case elfcpp::R_386_COPY:
1319     case elfcpp::R_386_GLOB_DAT:
1320     case elfcpp::R_386_JUMP_SLOT:
1321     case elfcpp::R_386_RELATIVE:
1322     case elfcpp::R_386_TLS_TPOFF:
1323     case elfcpp::R_386_TLS_DTPMOD32:
1324     case elfcpp::R_386_TLS_DTPOFF32:
1325     case elfcpp::R_386_TLS_TPOFF32:
1326     case elfcpp::R_386_TLS_DESC:
1327       gold_error(_("%s: unexpected reloc %u in object file"),
1328                  object->name().c_str(), r_type);
1329       break;
1330
1331       // These are initial tls relocs, which are expected when
1332       // linking.
1333     case elfcpp::R_386_TLS_GD:            // Global-dynamic
1334     case elfcpp::R_386_TLS_GOTDESC:       // Global-dynamic (from ~oliva url)
1335     case elfcpp::R_386_TLS_DESC_CALL:
1336     case elfcpp::R_386_TLS_LDM:           // Local-dynamic
1337     case elfcpp::R_386_TLS_LDO_32:        // Alternate local-dynamic
1338     case elfcpp::R_386_TLS_IE:            // Initial-exec
1339     case elfcpp::R_386_TLS_IE_32:
1340     case elfcpp::R_386_TLS_GOTIE:
1341     case elfcpp::R_386_TLS_LE:            // Local-exec
1342     case elfcpp::R_386_TLS_LE_32:
1343       {
1344         const bool is_final = gsym->final_value_is_known();
1345         const tls::Tls_optimization optimized_type
1346             = Target_i386::optimize_tls_reloc(is_final, r_type);
1347         switch (r_type)
1348           {
1349           case elfcpp::R_386_TLS_GD:          // Global-dynamic
1350             if (optimized_type == tls::TLSOPT_NONE)
1351               {
1352                 // Create a pair of GOT entries for the module index and
1353                 // dtv-relative offset.
1354                 Output_data_got<32, false>* got
1355                     = target->got_section(symtab, layout);
1356                 got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_PAIR,
1357                                              target->rel_dyn_section(layout),
1358                                              elfcpp::R_386_TLS_DTPMOD32,
1359                                              elfcpp::R_386_TLS_DTPOFF32);
1360               }
1361             else if (optimized_type == tls::TLSOPT_TO_IE)
1362               {
1363                 // Create a GOT entry for the tp-relative offset.
1364                 Output_data_got<32, false>* got
1365                     = target->got_section(symtab, layout);
1366                 got->add_global_with_rel(gsym, GOT_TYPE_TLS_NOFFSET,
1367                                          target->rel_dyn_section(layout),
1368                                          elfcpp::R_386_TLS_TPOFF);
1369               }
1370             else if (optimized_type != tls::TLSOPT_TO_LE)
1371               unsupported_reloc_global(object, r_type, gsym);
1372             break;
1373
1374           case elfcpp::R_386_TLS_GOTDESC:     // Global-dynamic (~oliva url)
1375             target->define_tls_base_symbol(symtab, layout);
1376             if (optimized_type == tls::TLSOPT_NONE)
1377               {
1378                 // Create a double GOT entry with an R_386_TLS_DESC reloc.
1379                 Output_data_got<32, false>* got
1380                     = target->got_section(symtab, layout);
1381                 got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_DESC,
1382                                              target->rel_dyn_section(layout),
1383                                              elfcpp::R_386_TLS_DESC, 0);
1384               }
1385             else if (optimized_type == tls::TLSOPT_TO_IE)
1386               {
1387                 // Create a GOT entry for the tp-relative offset.
1388                 Output_data_got<32, false>* got
1389                     = target->got_section(symtab, layout);
1390                 got->add_global_with_rel(gsym, GOT_TYPE_TLS_NOFFSET,
1391                                          target->rel_dyn_section(layout),
1392                                          elfcpp::R_386_TLS_TPOFF);
1393               }
1394             else if (optimized_type != tls::TLSOPT_TO_LE)
1395               unsupported_reloc_global(object, r_type, gsym);
1396             break;
1397
1398           case elfcpp::R_386_TLS_DESC_CALL:
1399             break;
1400
1401           case elfcpp::R_386_TLS_LDM:         // Local-dynamic
1402             if (optimized_type == tls::TLSOPT_NONE)
1403               {
1404                 // Create a GOT entry for the module index.
1405                 target->got_mod_index_entry(symtab, layout, object);
1406               }
1407             else if (optimized_type != tls::TLSOPT_TO_LE)
1408               unsupported_reloc_global(object, r_type, gsym);
1409             break;
1410
1411           case elfcpp::R_386_TLS_LDO_32:      // Alternate local-dynamic
1412             break;
1413
1414           case elfcpp::R_386_TLS_IE:          // Initial-exec
1415           case elfcpp::R_386_TLS_IE_32:
1416           case elfcpp::R_386_TLS_GOTIE:
1417             layout->set_has_static_tls();
1418             if (optimized_type == tls::TLSOPT_NONE)
1419               {
1420                 // For the R_386_TLS_IE relocation, we need to create a
1421                 // dynamic relocation when building a shared library.
1422                 if (r_type == elfcpp::R_386_TLS_IE
1423                     && parameters->options().shared())
1424                   {
1425                     Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1426                     rel_dyn->add_global_relative(gsym, elfcpp::R_386_RELATIVE,
1427                                                  output_section, object,
1428                                                  data_shndx,
1429                                                  reloc.get_r_offset());
1430                   }
1431                 // Create a GOT entry for the tp-relative offset.
1432                 Output_data_got<32, false>* got
1433                     = target->got_section(symtab, layout);
1434                 unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_IE_32
1435                                            ? elfcpp::R_386_TLS_TPOFF32
1436                                            : elfcpp::R_386_TLS_TPOFF);
1437                 unsigned int got_type = (r_type == elfcpp::R_386_TLS_IE_32
1438                                          ? GOT_TYPE_TLS_OFFSET
1439                                          : GOT_TYPE_TLS_NOFFSET);
1440                 got->add_global_with_rel(gsym, got_type,
1441                                          target->rel_dyn_section(layout),
1442                                          dyn_r_type);
1443               }
1444             else if (optimized_type != tls::TLSOPT_TO_LE)
1445               unsupported_reloc_global(object, r_type, gsym);
1446             break;
1447
1448           case elfcpp::R_386_TLS_LE:          // Local-exec
1449           case elfcpp::R_386_TLS_LE_32:
1450             layout->set_has_static_tls();
1451             if (parameters->options().shared())
1452               {
1453                 // We need to create a dynamic relocation.
1454                 unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_LE_32
1455                                            ? elfcpp::R_386_TLS_TPOFF32
1456                                            : elfcpp::R_386_TLS_TPOFF);
1457                 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1458                 rel_dyn->add_global(gsym, dyn_r_type, output_section, object,
1459                                     data_shndx, reloc.get_r_offset());
1460               }
1461             break;
1462
1463           default:
1464             gold_unreachable();
1465           }
1466       }
1467       break;
1468
1469     case elfcpp::R_386_32PLT:
1470     case elfcpp::R_386_TLS_GD_32:
1471     case elfcpp::R_386_TLS_GD_PUSH:
1472     case elfcpp::R_386_TLS_GD_CALL:
1473     case elfcpp::R_386_TLS_GD_POP:
1474     case elfcpp::R_386_TLS_LDM_32:
1475     case elfcpp::R_386_TLS_LDM_PUSH:
1476     case elfcpp::R_386_TLS_LDM_CALL:
1477     case elfcpp::R_386_TLS_LDM_POP:
1478     case elfcpp::R_386_USED_BY_INTEL_200:
1479     default:
1480       unsupported_reloc_global(object, r_type, gsym);
1481       break;
1482     }
1483 }
1484
1485 // Process relocations for gc.
1486
1487 void
1488 Target_i386::gc_process_relocs(Symbol_table* symtab,
1489                                Layout* layout,
1490                                Sized_relobj<32, false>* object,
1491                                unsigned int data_shndx,
1492                                unsigned int,
1493                                const unsigned char* prelocs,
1494                                size_t reloc_count,
1495                                Output_section* output_section,
1496                                bool needs_special_offset_handling,
1497                                size_t local_symbol_count,
1498                                const unsigned char* plocal_symbols)
1499 {
1500   gold::gc_process_relocs<32, false, Target_i386, elfcpp::SHT_REL,
1501                           Target_i386::Scan>(
1502     symtab,
1503     layout,
1504     this,
1505     object,
1506     data_shndx,
1507     prelocs,
1508     reloc_count,
1509     output_section,
1510     needs_special_offset_handling,
1511     local_symbol_count,
1512     plocal_symbols);
1513 }
1514
1515 // Scan relocations for a section.
1516
1517 void
1518 Target_i386::scan_relocs(Symbol_table* symtab,
1519                          Layout* layout,
1520                          Sized_relobj<32, false>* object,
1521                          unsigned int data_shndx,
1522                          unsigned int sh_type,
1523                          const unsigned char* prelocs,
1524                          size_t reloc_count,
1525                          Output_section* output_section,
1526                          bool needs_special_offset_handling,
1527                          size_t local_symbol_count,
1528                          const unsigned char* plocal_symbols)
1529 {
1530   if (sh_type == elfcpp::SHT_RELA)
1531     {
1532       gold_error(_("%s: unsupported RELA reloc section"),
1533                  object->name().c_str());
1534       return;
1535     }
1536
1537   gold::scan_relocs<32, false, Target_i386, elfcpp::SHT_REL,
1538                     Target_i386::Scan>(
1539     symtab,
1540     layout,
1541     this,
1542     object,
1543     data_shndx,
1544     prelocs,
1545     reloc_count,
1546     output_section,
1547     needs_special_offset_handling,
1548     local_symbol_count,
1549     plocal_symbols);
1550 }
1551
1552 // Finalize the sections.
1553
1554 void
1555 Target_i386::do_finalize_sections(Layout* layout, const Input_objects*)
1556 {
1557   // Fill in some more dynamic tags.
1558   Output_data_dynamic* const odyn = layout->dynamic_data();
1559   if (odyn != NULL)
1560     {
1561       if (this->got_plt_ != NULL
1562           && this->got_plt_->output_section() != NULL)
1563         odyn->add_section_address(elfcpp::DT_PLTGOT, this->got_plt_);
1564
1565       if (this->plt_ != NULL
1566           && this->plt_->output_section() != NULL)
1567         {
1568           const Output_data* od = this->plt_->rel_plt();
1569           odyn->add_section_size(elfcpp::DT_PLTRELSZ, od);
1570           odyn->add_section_address(elfcpp::DT_JMPREL, od);
1571           odyn->add_constant(elfcpp::DT_PLTREL, elfcpp::DT_REL);
1572         }
1573
1574       if (this->rel_dyn_ != NULL
1575           && this->rel_dyn_->output_section() != NULL)
1576         {
1577           const Output_data* od = this->rel_dyn_;
1578           odyn->add_section_address(elfcpp::DT_REL, od);
1579           odyn->add_section_size(elfcpp::DT_RELSZ, od);
1580           odyn->add_constant(elfcpp::DT_RELENT,
1581                              elfcpp::Elf_sizes<32>::rel_size);
1582         }
1583
1584       if (!parameters->options().shared())
1585         {
1586           // The value of the DT_DEBUG tag is filled in by the dynamic
1587           // linker at run time, and used by the debugger.
1588           odyn->add_constant(elfcpp::DT_DEBUG, 0);
1589         }
1590     }
1591
1592   // Emit any relocs we saved in an attempt to avoid generating COPY
1593   // relocs.
1594   if (this->copy_relocs_.any_saved_relocs())
1595     this->copy_relocs_.emit(this->rel_dyn_section(layout));
1596 }
1597
1598 // Return whether a direct absolute static relocation needs to be applied.
1599 // In cases where Scan::local() or Scan::global() has created
1600 // a dynamic relocation other than R_386_RELATIVE, the addend
1601 // of the relocation is carried in the data, and we must not
1602 // apply the static relocation.
1603
1604 inline bool
1605 Target_i386::Relocate::should_apply_static_reloc(const Sized_symbol<32>* gsym,
1606                                                  int ref_flags,
1607                                                  bool is_32bit,
1608                                                  Output_section* output_section)
1609 {
1610   // If the output section is not allocated, then we didn't call
1611   // scan_relocs, we didn't create a dynamic reloc, and we must apply
1612   // the reloc here.
1613   if ((output_section->flags() & elfcpp::SHF_ALLOC) == 0)
1614     return true;
1615
1616   // For local symbols, we will have created a non-RELATIVE dynamic
1617   // relocation only if (a) the output is position independent,
1618   // (b) the relocation is absolute (not pc- or segment-relative), and
1619   // (c) the relocation is not 32 bits wide.
1620   if (gsym == NULL)
1621     return !(parameters->options().output_is_position_independent()
1622              && (ref_flags & Symbol::ABSOLUTE_REF)
1623              && !is_32bit);
1624
1625   // For global symbols, we use the same helper routines used in the
1626   // scan pass.  If we did not create a dynamic relocation, or if we
1627   // created a RELATIVE dynamic relocation, we should apply the static
1628   // relocation.
1629   bool has_dyn = gsym->needs_dynamic_reloc(ref_flags);
1630   bool is_rel = (ref_flags & Symbol::ABSOLUTE_REF)
1631                 && gsym->can_use_relative_reloc(ref_flags
1632                                                 & Symbol::FUNCTION_CALL);
1633   return !has_dyn || is_rel;
1634 }
1635
1636 // Perform a relocation.
1637
1638 inline bool
1639 Target_i386::Relocate::relocate(const Relocate_info<32, false>* relinfo,
1640                                 Target_i386* target,
1641                                 Output_section *output_section,
1642                                 size_t relnum,
1643                                 const elfcpp::Rel<32, false>& rel,
1644                                 unsigned int r_type,
1645                                 const Sized_symbol<32>* gsym,
1646                                 const Symbol_value<32>* psymval,
1647                                 unsigned char* view,
1648                                 elfcpp::Elf_types<32>::Elf_Addr address,
1649                                 section_size_type view_size)
1650 {
1651   if (this->skip_call_tls_get_addr_)
1652     {
1653       if ((r_type != elfcpp::R_386_PLT32
1654            && r_type != elfcpp::R_386_PC32)
1655           || gsym == NULL
1656           || strcmp(gsym->name(), "___tls_get_addr") != 0)
1657         gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
1658                                _("missing expected TLS relocation"));
1659       else
1660         {
1661           this->skip_call_tls_get_addr_ = false;
1662           return false;
1663         }
1664     }
1665
1666   // Pick the value to use for symbols defined in shared objects.
1667   Symbol_value<32> symval;
1668   if (gsym != NULL
1669       && gsym->use_plt_offset(r_type == elfcpp::R_386_PC8
1670                               || r_type == elfcpp::R_386_PC16
1671                               || r_type == elfcpp::R_386_PC32))
1672     {
1673       symval.set_output_value(target->plt_section()->address()
1674                               + gsym->plt_offset());
1675       psymval = &symval;
1676     }
1677
1678   const Sized_relobj<32, false>* object = relinfo->object;
1679
1680   // Get the GOT offset if needed.
1681   // The GOT pointer points to the end of the GOT section.
1682   // We need to subtract the size of the GOT section to get
1683   // the actual offset to use in the relocation.
1684   bool have_got_offset = false;
1685   unsigned int got_offset = 0;
1686   switch (r_type)
1687     {
1688     case elfcpp::R_386_GOT32:
1689       if (gsym != NULL)
1690         {
1691           gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
1692           got_offset = (gsym->got_offset(GOT_TYPE_STANDARD)
1693                         - target->got_size());
1694         }
1695       else
1696         {
1697           unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
1698           gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD));
1699           got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD)
1700                         - target->got_size());
1701         }
1702       have_got_offset = true;
1703       break;
1704
1705     default:
1706       break;
1707     }
1708
1709   switch (r_type)
1710     {
1711     case elfcpp::R_386_NONE:
1712     case elfcpp::R_386_GNU_VTINHERIT:
1713     case elfcpp::R_386_GNU_VTENTRY:
1714       break;
1715
1716     case elfcpp::R_386_32:
1717       if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, true,
1718                                     output_section))
1719         Relocate_functions<32, false>::rel32(view, object, psymval);
1720       break;
1721
1722     case elfcpp::R_386_PC32:
1723       {
1724         int ref_flags = Symbol::NON_PIC_REF;
1725         if (gsym != NULL && gsym->type() == elfcpp::STT_FUNC)
1726           ref_flags |= Symbol::FUNCTION_CALL;
1727         if (should_apply_static_reloc(gsym, ref_flags, true, output_section))
1728           Relocate_functions<32, false>::pcrel32(view, object, psymval, address);
1729       }
1730       break;
1731
1732     case elfcpp::R_386_16:
1733       if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
1734                                     output_section))
1735         Relocate_functions<32, false>::rel16(view, object, psymval);
1736       break;
1737
1738     case elfcpp::R_386_PC16:
1739       {
1740         int ref_flags = Symbol::NON_PIC_REF;
1741         if (gsym != NULL && gsym->type() == elfcpp::STT_FUNC)
1742           ref_flags |= Symbol::FUNCTION_CALL;
1743         if (should_apply_static_reloc(gsym, ref_flags, false, output_section))
1744           Relocate_functions<32, false>::pcrel16(view, object, psymval, address);
1745       }
1746       break;
1747
1748     case elfcpp::R_386_8:
1749       if (should_apply_static_reloc(gsym, Symbol::ABSOLUTE_REF, false,
1750                                     output_section))
1751         Relocate_functions<32, false>::rel8(view, object, psymval);
1752       break;
1753
1754     case elfcpp::R_386_PC8:
1755       {
1756         int ref_flags = Symbol::NON_PIC_REF;
1757         if (gsym != NULL && gsym->type() == elfcpp::STT_FUNC)
1758           ref_flags |= Symbol::FUNCTION_CALL;
1759         if (should_apply_static_reloc(gsym, ref_flags, false,
1760                                       output_section))
1761           Relocate_functions<32, false>::pcrel8(view, object, psymval, address);
1762       }
1763       break;
1764
1765     case elfcpp::R_386_PLT32:
1766       gold_assert(gsym == NULL
1767                   || gsym->has_plt_offset()
1768                   || gsym->final_value_is_known()
1769                   || (gsym->is_defined()
1770                       && !gsym->is_from_dynobj()
1771                       && !gsym->is_preemptible()));
1772       Relocate_functions<32, false>::pcrel32(view, object, psymval, address);
1773       break;
1774
1775     case elfcpp::R_386_GOT32:
1776       gold_assert(have_got_offset);
1777       Relocate_functions<32, false>::rel32(view, got_offset);
1778       break;
1779
1780     case elfcpp::R_386_GOTOFF:
1781       {
1782         elfcpp::Elf_types<32>::Elf_Addr value;
1783         value = (psymval->value(object, 0)
1784                  - target->got_plt_section()->address());
1785         Relocate_functions<32, false>::rel32(view, value);
1786       }
1787       break;
1788
1789     case elfcpp::R_386_GOTPC:
1790       {
1791         elfcpp::Elf_types<32>::Elf_Addr value;
1792         value = target->got_plt_section()->address();
1793         Relocate_functions<32, false>::pcrel32(view, value, address);
1794       }
1795       break;
1796
1797     case elfcpp::R_386_COPY:
1798     case elfcpp::R_386_GLOB_DAT:
1799     case elfcpp::R_386_JUMP_SLOT:
1800     case elfcpp::R_386_RELATIVE:
1801       // These are outstanding tls relocs, which are unexpected when
1802       // linking.
1803     case elfcpp::R_386_TLS_TPOFF:
1804     case elfcpp::R_386_TLS_DTPMOD32:
1805     case elfcpp::R_386_TLS_DTPOFF32:
1806     case elfcpp::R_386_TLS_TPOFF32:
1807     case elfcpp::R_386_TLS_DESC:
1808       gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
1809                              _("unexpected reloc %u in object file"),
1810                              r_type);
1811       break;
1812
1813       // These are initial tls relocs, which are expected when
1814       // linking.
1815     case elfcpp::R_386_TLS_GD:             // Global-dynamic
1816     case elfcpp::R_386_TLS_GOTDESC:        // Global-dynamic (from ~oliva url)
1817     case elfcpp::R_386_TLS_DESC_CALL:
1818     case elfcpp::R_386_TLS_LDM:            // Local-dynamic
1819     case elfcpp::R_386_TLS_LDO_32:         // Alternate local-dynamic
1820     case elfcpp::R_386_TLS_IE:             // Initial-exec
1821     case elfcpp::R_386_TLS_IE_32:
1822     case elfcpp::R_386_TLS_GOTIE:
1823     case elfcpp::R_386_TLS_LE:             // Local-exec
1824     case elfcpp::R_386_TLS_LE_32:
1825       this->relocate_tls(relinfo, target, relnum, rel, r_type, gsym, psymval,
1826                          view, address, view_size);
1827       break;
1828
1829     case elfcpp::R_386_32PLT:
1830     case elfcpp::R_386_TLS_GD_32:
1831     case elfcpp::R_386_TLS_GD_PUSH:
1832     case elfcpp::R_386_TLS_GD_CALL:
1833     case elfcpp::R_386_TLS_GD_POP:
1834     case elfcpp::R_386_TLS_LDM_32:
1835     case elfcpp::R_386_TLS_LDM_PUSH:
1836     case elfcpp::R_386_TLS_LDM_CALL:
1837     case elfcpp::R_386_TLS_LDM_POP:
1838     case elfcpp::R_386_USED_BY_INTEL_200:
1839     default:
1840       gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
1841                              _("unsupported reloc %u"),
1842                              r_type);
1843       break;
1844     }
1845
1846   return true;
1847 }
1848
1849 // Perform a TLS relocation.
1850
1851 inline void
1852 Target_i386::Relocate::relocate_tls(const Relocate_info<32, false>* relinfo,
1853                                     Target_i386* target,
1854                                     size_t relnum,
1855                                     const elfcpp::Rel<32, false>& rel,
1856                                     unsigned int r_type,
1857                                     const Sized_symbol<32>* gsym,
1858                                     const Symbol_value<32>* psymval,
1859                                     unsigned char* view,
1860                                     elfcpp::Elf_types<32>::Elf_Addr,
1861                                     section_size_type view_size)
1862 {
1863   Output_segment* tls_segment = relinfo->layout->tls_segment();
1864
1865   const Sized_relobj<32, false>* object = relinfo->object;
1866
1867   elfcpp::Elf_types<32>::Elf_Addr value = psymval->value(object, 0);
1868
1869   const bool is_final =
1870     (gsym == NULL
1871      ? !parameters->options().output_is_position_independent()
1872      : gsym->final_value_is_known());
1873   const tls::Tls_optimization optimized_type
1874       = Target_i386::optimize_tls_reloc(is_final, r_type);
1875   switch (r_type)
1876     {
1877     case elfcpp::R_386_TLS_GD:           // Global-dynamic
1878       if (optimized_type == tls::TLSOPT_TO_LE)
1879         {
1880           gold_assert(tls_segment != NULL);
1881           this->tls_gd_to_le(relinfo, relnum, tls_segment,
1882                              rel, r_type, value, view,
1883                              view_size);
1884           break;
1885         }
1886       else
1887         {
1888           unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE
1889                                    ? GOT_TYPE_TLS_NOFFSET
1890                                    : GOT_TYPE_TLS_PAIR);
1891           unsigned int got_offset;
1892           if (gsym != NULL)
1893             {
1894               gold_assert(gsym->has_got_offset(got_type));
1895               got_offset = gsym->got_offset(got_type) - target->got_size();
1896             }
1897           else
1898             {
1899               unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
1900               gold_assert(object->local_has_got_offset(r_sym, got_type));
1901               got_offset = (object->local_got_offset(r_sym, got_type)
1902                             - target->got_size());
1903             }
1904           if (optimized_type == tls::TLSOPT_TO_IE)
1905             {
1906               gold_assert(tls_segment != NULL);
1907               this->tls_gd_to_ie(relinfo, relnum, tls_segment, rel, r_type,
1908                                  got_offset, view, view_size);
1909               break;
1910             }
1911           else if (optimized_type == tls::TLSOPT_NONE)
1912             {
1913               // Relocate the field with the offset of the pair of GOT
1914               // entries.
1915               Relocate_functions<32, false>::rel32(view, got_offset);
1916               break;
1917             }
1918         }
1919       gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
1920                              _("unsupported reloc %u"),
1921                              r_type);
1922       break;
1923
1924     case elfcpp::R_386_TLS_GOTDESC:      // Global-dynamic (from ~oliva url)
1925     case elfcpp::R_386_TLS_DESC_CALL:
1926       this->local_dynamic_type_ = LOCAL_DYNAMIC_GNU;
1927       if (optimized_type == tls::TLSOPT_TO_LE)
1928         {
1929           gold_assert(tls_segment != NULL);
1930           this->tls_desc_gd_to_le(relinfo, relnum, tls_segment,
1931                                   rel, r_type, value, view,
1932                                   view_size);
1933           break;
1934         }
1935       else
1936         {
1937           unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE
1938                                    ? GOT_TYPE_TLS_NOFFSET
1939                                    : GOT_TYPE_TLS_DESC);
1940           unsigned int got_offset;
1941           if (gsym != NULL)
1942             {
1943               gold_assert(gsym->has_got_offset(got_type));
1944               got_offset = gsym->got_offset(got_type) - target->got_size();
1945             }
1946           else
1947             {
1948               unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
1949               gold_assert(object->local_has_got_offset(r_sym, got_type));
1950               got_offset = (object->local_got_offset(r_sym, got_type)
1951                             - target->got_size());
1952             }
1953           if (optimized_type == tls::TLSOPT_TO_IE)
1954             {
1955               gold_assert(tls_segment != NULL);
1956               this->tls_desc_gd_to_ie(relinfo, relnum, tls_segment, rel, r_type,
1957                                       got_offset, view, view_size);
1958               break;
1959             }
1960           else if (optimized_type == tls::TLSOPT_NONE)
1961             {
1962               if (r_type == elfcpp::R_386_TLS_GOTDESC)
1963                 {
1964                   // Relocate the field with the offset of the pair of GOT
1965                   // entries.
1966                   Relocate_functions<32, false>::rel32(view, got_offset);
1967                 }
1968               break;
1969             }
1970         }
1971       gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
1972                              _("unsupported reloc %u"),
1973                              r_type);
1974       break;
1975
1976     case elfcpp::R_386_TLS_LDM:          // Local-dynamic
1977       if (this->local_dynamic_type_ == LOCAL_DYNAMIC_SUN)
1978         {
1979           gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
1980                                  _("both SUN and GNU model "
1981                                    "TLS relocations"));
1982           break;
1983         }
1984       this->local_dynamic_type_ = LOCAL_DYNAMIC_GNU;
1985       if (optimized_type == tls::TLSOPT_TO_LE)
1986         {
1987           gold_assert(tls_segment != NULL);
1988           this->tls_ld_to_le(relinfo, relnum, tls_segment, rel, r_type,
1989                              value, view, view_size);
1990           break;
1991         }
1992       else if (optimized_type == tls::TLSOPT_NONE)
1993         {
1994           // Relocate the field with the offset of the GOT entry for
1995           // the module index.
1996           unsigned int got_offset;
1997           got_offset = (target->got_mod_index_entry(NULL, NULL, NULL)
1998                         - target->got_size());
1999           Relocate_functions<32, false>::rel32(view, got_offset);
2000           break;
2001         }
2002       gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
2003                              _("unsupported reloc %u"),
2004                              r_type);
2005       break;
2006
2007     case elfcpp::R_386_TLS_LDO_32:       // Alternate local-dynamic
2008       if (optimized_type == tls::TLSOPT_TO_LE)
2009         {
2010           // This reloc can appear in debugging sections, in which
2011           // case we must not convert to local-exec.  We decide what
2012           // to do based on whether the section is marked as
2013           // containing executable code.  That is what the GNU linker
2014           // does as well.
2015           elfcpp::Shdr<32, false> shdr(relinfo->data_shdr);
2016           if ((shdr.get_sh_flags() & elfcpp::SHF_EXECINSTR) != 0)
2017             {
2018               gold_assert(tls_segment != NULL);
2019               value -= tls_segment->memsz();
2020             }
2021         }
2022       Relocate_functions<32, false>::rel32(view, value);
2023       break;
2024
2025     case elfcpp::R_386_TLS_IE:           // Initial-exec
2026     case elfcpp::R_386_TLS_GOTIE:
2027     case elfcpp::R_386_TLS_IE_32:
2028       if (optimized_type == tls::TLSOPT_TO_LE)
2029         {
2030           gold_assert(tls_segment != NULL);
2031           Target_i386::Relocate::tls_ie_to_le(relinfo, relnum, tls_segment,
2032                                               rel, r_type, value, view,
2033                                               view_size);
2034           break;
2035         }
2036       else if (optimized_type == tls::TLSOPT_NONE)
2037         {
2038           // Relocate the field with the offset of the GOT entry for
2039           // the tp-relative offset of the symbol.
2040           unsigned int got_type = (r_type == elfcpp::R_386_TLS_IE_32
2041                                    ? GOT_TYPE_TLS_OFFSET
2042                                    : GOT_TYPE_TLS_NOFFSET);
2043           unsigned int got_offset;
2044           if (gsym != NULL)
2045             {
2046               gold_assert(gsym->has_got_offset(got_type));
2047               got_offset = gsym->got_offset(got_type);
2048             }
2049           else
2050             {
2051               unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
2052               gold_assert(object->local_has_got_offset(r_sym, got_type));
2053               got_offset = object->local_got_offset(r_sym, got_type);
2054             }
2055           // For the R_386_TLS_IE relocation, we need to apply the
2056           // absolute address of the GOT entry.
2057           if (r_type == elfcpp::R_386_TLS_IE)
2058             got_offset += target->got_plt_section()->address();
2059           // All GOT offsets are relative to the end of the GOT.
2060           got_offset -= target->got_size();
2061           Relocate_functions<32, false>::rel32(view, got_offset);
2062           break;
2063         }
2064       gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
2065                              _("unsupported reloc %u"),
2066                              r_type);
2067       break;
2068
2069     case elfcpp::R_386_TLS_LE:           // Local-exec
2070       // If we're creating a shared library, a dynamic relocation will
2071       // have been created for this location, so do not apply it now.
2072       if (!parameters->options().shared())
2073         {
2074           gold_assert(tls_segment != NULL);
2075           value -= tls_segment->memsz();
2076           Relocate_functions<32, false>::rel32(view, value);
2077         }
2078       break;
2079
2080     case elfcpp::R_386_TLS_LE_32:
2081       // If we're creating a shared library, a dynamic relocation will
2082       // have been created for this location, so do not apply it now.
2083       if (!parameters->options().shared())
2084         {
2085           gold_assert(tls_segment != NULL);
2086           value = tls_segment->memsz() - value;
2087           Relocate_functions<32, false>::rel32(view, value);
2088         }
2089       break;
2090     }
2091 }
2092
2093 // Do a relocation in which we convert a TLS General-Dynamic to a
2094 // Local-Exec.
2095
2096 inline void
2097 Target_i386::Relocate::tls_gd_to_le(const Relocate_info<32, false>* relinfo,
2098                                     size_t relnum,
2099                                     Output_segment* tls_segment,
2100                                     const elfcpp::Rel<32, false>& rel,
2101                                     unsigned int,
2102                                     elfcpp::Elf_types<32>::Elf_Addr value,
2103                                     unsigned char* view,
2104                                     section_size_type view_size)
2105 {
2106   // leal foo(,%reg,1),%eax; call ___tls_get_addr
2107   //  ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
2108   // leal foo(%reg),%eax; call ___tls_get_addr
2109   //  ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
2110
2111   tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
2112   tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 9);
2113
2114   unsigned char op1 = view[-1];
2115   unsigned char op2 = view[-2];
2116
2117   tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2118                  op2 == 0x8d || op2 == 0x04);
2119   tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[4] == 0xe8);
2120
2121   int roff = 5;
2122
2123   if (op2 == 0x04)
2124     {
2125       tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -3);
2126       tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[-3] == 0x8d);
2127       tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2128                      ((op1 & 0xc7) == 0x05 && op1 != (4 << 3)));
2129       memcpy(view - 3, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
2130     }
2131   else
2132     {
2133       tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2134                      (op1 & 0xf8) == 0x80 && (op1 & 7) != 4);
2135       if (rel.get_r_offset() + 9 < view_size
2136           && view[9] == 0x90)
2137         {
2138           // There is a trailing nop.  Use the size byte subl.
2139           memcpy(view - 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
2140           roff = 6;
2141         }
2142       else
2143         {
2144           // Use the five byte subl.
2145           memcpy(view - 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
2146         }
2147     }
2148
2149   value = tls_segment->memsz() - value;
2150   Relocate_functions<32, false>::rel32(view + roff, value);
2151
2152   // The next reloc should be a PLT32 reloc against __tls_get_addr.
2153   // We can skip it.
2154   this->skip_call_tls_get_addr_ = true;
2155 }
2156
2157 // Do a relocation in which we convert a TLS General-Dynamic to an
2158 // Initial-Exec.
2159
2160 inline void
2161 Target_i386::Relocate::tls_gd_to_ie(const Relocate_info<32, false>* relinfo,
2162                                     size_t relnum,
2163                                     Output_segment*,
2164                                     const elfcpp::Rel<32, false>& rel,
2165                                     unsigned int,
2166                                     elfcpp::Elf_types<32>::Elf_Addr value,
2167                                     unsigned char* view,
2168                                     section_size_type view_size)
2169 {
2170   // leal foo(,%ebx,1),%eax; call ___tls_get_addr
2171   //  ==> movl %gs:0,%eax; addl foo@gotntpoff(%ebx),%eax
2172
2173   tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
2174   tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 9);
2175
2176   unsigned char op1 = view[-1];
2177   unsigned char op2 = view[-2];
2178
2179   tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2180                  op2 == 0x8d || op2 == 0x04);
2181   tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[4] == 0xe8);
2182
2183   int roff = 5;
2184
2185   // FIXME: For now, support only the first (SIB) form.
2186   tls::check_tls(relinfo, relnum, rel.get_r_offset(), op2 == 0x04);
2187
2188   if (op2 == 0x04)
2189     {
2190       tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -3);
2191       tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[-3] == 0x8d);
2192       tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2193                      ((op1 & 0xc7) == 0x05 && op1 != (4 << 3)));
2194       memcpy(view - 3, "\x65\xa1\0\0\0\0\x03\x83\0\0\0", 12);
2195     }
2196   else
2197     {
2198       tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2199                      (op1 & 0xf8) == 0x80 && (op1 & 7) != 4);
2200       if (rel.get_r_offset() + 9 < view_size
2201           && view[9] == 0x90)
2202         {
2203           // FIXME: This is not the right instruction sequence.
2204           // There is a trailing nop.  Use the size byte subl.
2205           memcpy(view - 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
2206           roff = 6;
2207         }
2208       else
2209         {
2210           // FIXME: This is not the right instruction sequence.
2211           // Use the five byte subl.
2212           memcpy(view - 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
2213         }
2214     }
2215
2216   Relocate_functions<32, false>::rel32(view + roff, value);
2217
2218   // The next reloc should be a PLT32 reloc against __tls_get_addr.
2219   // We can skip it.
2220   this->skip_call_tls_get_addr_ = true;
2221 }
2222
2223 // Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL
2224 // General-Dynamic to a Local-Exec.
2225
2226 inline void
2227 Target_i386::Relocate::tls_desc_gd_to_le(
2228     const Relocate_info<32, false>* relinfo,
2229     size_t relnum,
2230     Output_segment* tls_segment,
2231     const elfcpp::Rel<32, false>& rel,
2232     unsigned int r_type,
2233     elfcpp::Elf_types<32>::Elf_Addr value,
2234     unsigned char* view,
2235     section_size_type view_size)
2236 {
2237   if (r_type == elfcpp::R_386_TLS_GOTDESC)
2238     {
2239       // leal foo@TLSDESC(%ebx), %eax
2240       // ==> leal foo@NTPOFF, %eax
2241       tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
2242       tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4);
2243       tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2244                      view[-2] == 0x8d && view[-1] == 0x83);
2245       view[-1] = 0x05;
2246       value -= tls_segment->memsz();
2247       Relocate_functions<32, false>::rel32(view, value);
2248     }
2249   else
2250     {
2251       // call *foo@TLSCALL(%eax)
2252       // ==> nop; nop
2253       gold_assert(r_type == elfcpp::R_386_TLS_DESC_CALL);
2254       tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 2);
2255       tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2256                      view[0] == 0xff && view[1] == 0x10);
2257       view[0] = 0x66;
2258       view[1] = 0x90;
2259     }
2260 }
2261
2262 // Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL
2263 // General-Dynamic to an Initial-Exec.
2264
2265 inline void
2266 Target_i386::Relocate::tls_desc_gd_to_ie(
2267     const Relocate_info<32, false>* relinfo,
2268     size_t relnum,
2269     Output_segment*,
2270     const elfcpp::Rel<32, false>& rel,
2271     unsigned int r_type,
2272     elfcpp::Elf_types<32>::Elf_Addr value,
2273     unsigned char* view,
2274     section_size_type view_size)
2275 {
2276   if (r_type == elfcpp::R_386_TLS_GOTDESC)
2277     {
2278       // leal foo@TLSDESC(%ebx), %eax
2279       // ==> movl foo@GOTNTPOFF(%ebx), %eax
2280       tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
2281       tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4);
2282       tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2283                      view[-2] == 0x8d && view[-1] == 0x83);
2284       view[-2] = 0x8b;
2285       Relocate_functions<32, false>::rel32(view, value);
2286     }
2287   else
2288     {
2289       // call *foo@TLSCALL(%eax)
2290       // ==> nop; nop
2291       gold_assert(r_type == elfcpp::R_386_TLS_DESC_CALL);
2292       tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 2);
2293       tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2294                      view[0] == 0xff && view[1] == 0x10);
2295       view[0] = 0x66;
2296       view[1] = 0x90;
2297     }
2298 }
2299
2300 // Do a relocation in which we convert a TLS Local-Dynamic to a
2301 // Local-Exec.
2302
2303 inline void
2304 Target_i386::Relocate::tls_ld_to_le(const Relocate_info<32, false>* relinfo,
2305                                     size_t relnum,
2306                                     Output_segment*,
2307                                     const elfcpp::Rel<32, false>& rel,
2308                                     unsigned int,
2309                                     elfcpp::Elf_types<32>::Elf_Addr,
2310                                     unsigned char* view,
2311                                     section_size_type view_size)
2312 {
2313   // leal foo(%reg), %eax; call ___tls_get_addr
2314   // ==> movl %gs:0,%eax; nop; leal 0(%esi,1),%esi
2315
2316   tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
2317   tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 9);
2318
2319   // FIXME: Does this test really always pass?
2320   tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2321                  view[-2] == 0x8d && view[-1] == 0x83);
2322
2323   tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[4] == 0xe8);
2324
2325   memcpy(view - 2, "\x65\xa1\0\0\0\0\x90\x8d\x74\x26\0", 11);
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 Initial-Exec to a
2333 // Local-Exec.
2334
2335 inline void
2336 Target_i386::Relocate::tls_ie_to_le(const Relocate_info<32, false>* relinfo,
2337                                     size_t relnum,
2338                                     Output_segment* tls_segment,
2339                                     const elfcpp::Rel<32, false>& rel,
2340                                     unsigned int r_type,
2341                                     elfcpp::Elf_types<32>::Elf_Addr value,
2342                                     unsigned char* view,
2343                                     section_size_type view_size)
2344 {
2345   // We have to actually change the instructions, which means that we
2346   // need to examine the opcodes to figure out which instruction we
2347   // are looking at.
2348   if (r_type == elfcpp::R_386_TLS_IE)
2349     {
2350       // movl %gs:XX,%eax  ==>  movl $YY,%eax
2351       // movl %gs:XX,%reg  ==>  movl $YY,%reg
2352       // addl %gs:XX,%reg  ==>  addl $YY,%reg
2353       tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -1);
2354       tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4);
2355
2356       unsigned char op1 = view[-1];
2357       if (op1 == 0xa1)
2358         {
2359           // movl XX,%eax  ==>  movl $YY,%eax
2360           view[-1] = 0xb8;
2361         }
2362       else
2363         {
2364           tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
2365
2366           unsigned char op2 = view[-2];
2367           if (op2 == 0x8b)
2368             {
2369               // movl XX,%reg  ==>  movl $YY,%reg
2370               tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2371                              (op1 & 0xc7) == 0x05);
2372               view[-2] = 0xc7;
2373               view[-1] = 0xc0 | ((op1 >> 3) & 7);
2374             }
2375           else if (op2 == 0x03)
2376             {
2377               // addl XX,%reg  ==>  addl $YY,%reg
2378               tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2379                              (op1 & 0xc7) == 0x05);
2380               view[-2] = 0x81;
2381               view[-1] = 0xc0 | ((op1 >> 3) & 7);
2382             }
2383           else
2384             tls::check_tls(relinfo, relnum, rel.get_r_offset(), 0);
2385         }
2386     }
2387   else
2388     {
2389       // subl %gs:XX(%reg1),%reg2  ==>  subl $YY,%reg2
2390       // movl %gs:XX(%reg1),%reg2  ==>  movl $YY,%reg2
2391       // addl %gs:XX(%reg1),%reg2  ==>  addl $YY,$reg2
2392       tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
2393       tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4);
2394
2395       unsigned char op1 = view[-1];
2396       unsigned char op2 = view[-2];
2397       tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2398                      (op1 & 0xc0) == 0x80 && (op1 & 7) != 4);
2399       if (op2 == 0x8b)
2400         {
2401           // movl %gs:XX(%reg1),%reg2  ==>  movl $YY,%reg2
2402           view[-2] = 0xc7;
2403           view[-1] = 0xc0 | ((op1 >> 3) & 7);
2404         }
2405       else if (op2 == 0x2b)
2406         {
2407           // subl %gs:XX(%reg1),%reg2  ==>  subl $YY,%reg2
2408           view[-2] = 0x81;
2409           view[-1] = 0xe8 | ((op1 >> 3) & 7);
2410         }
2411       else if (op2 == 0x03)
2412         {
2413           // addl %gs:XX(%reg1),%reg2  ==>  addl $YY,$reg2
2414           view[-2] = 0x81;
2415           view[-1] = 0xc0 | ((op1 >> 3) & 7);
2416         }
2417       else
2418         tls::check_tls(relinfo, relnum, rel.get_r_offset(), 0);
2419     }
2420
2421   value = tls_segment->memsz() - value;
2422   if (r_type == elfcpp::R_386_TLS_IE || r_type == elfcpp::R_386_TLS_GOTIE)
2423     value = - value;
2424
2425   Relocate_functions<32, false>::rel32(view, value);
2426 }
2427
2428 // Relocate section data.
2429
2430 void
2431 Target_i386::relocate_section(const Relocate_info<32, false>* relinfo,
2432                               unsigned int sh_type,
2433                               const unsigned char* prelocs,
2434                               size_t reloc_count,
2435                               Output_section* output_section,
2436                               bool needs_special_offset_handling,
2437                               unsigned char* view,
2438                               elfcpp::Elf_types<32>::Elf_Addr address,
2439                               section_size_type view_size,
2440                               const Reloc_symbol_changes* reloc_symbol_changes)
2441 {
2442   gold_assert(sh_type == elfcpp::SHT_REL);
2443
2444   gold::relocate_section<32, false, Target_i386, elfcpp::SHT_REL,
2445                          Target_i386::Relocate>(
2446     relinfo,
2447     this,
2448     prelocs,
2449     reloc_count,
2450     output_section,
2451     needs_special_offset_handling,
2452     view,
2453     address,
2454     view_size,
2455     reloc_symbol_changes);
2456 }
2457
2458 // Return the size of a relocation while scanning during a relocatable
2459 // link.
2460
2461 unsigned int
2462 Target_i386::Relocatable_size_for_reloc::get_size_for_reloc(
2463     unsigned int r_type,
2464     Relobj* object)
2465 {
2466   switch (r_type)
2467     {
2468     case elfcpp::R_386_NONE:
2469     case elfcpp::R_386_GNU_VTINHERIT:
2470     case elfcpp::R_386_GNU_VTENTRY:
2471     case elfcpp::R_386_TLS_GD:            // Global-dynamic
2472     case elfcpp::R_386_TLS_GOTDESC:       // Global-dynamic (from ~oliva url)
2473     case elfcpp::R_386_TLS_DESC_CALL:
2474     case elfcpp::R_386_TLS_LDM:           // Local-dynamic
2475     case elfcpp::R_386_TLS_LDO_32:        // Alternate local-dynamic
2476     case elfcpp::R_386_TLS_IE:            // Initial-exec
2477     case elfcpp::R_386_TLS_IE_32:
2478     case elfcpp::R_386_TLS_GOTIE:
2479     case elfcpp::R_386_TLS_LE:            // Local-exec
2480     case elfcpp::R_386_TLS_LE_32:
2481       return 0;
2482
2483     case elfcpp::R_386_32:
2484     case elfcpp::R_386_PC32:
2485     case elfcpp::R_386_GOT32:
2486     case elfcpp::R_386_PLT32:
2487     case elfcpp::R_386_GOTOFF:
2488     case elfcpp::R_386_GOTPC:
2489      return 4;
2490
2491     case elfcpp::R_386_16:
2492     case elfcpp::R_386_PC16:
2493       return 2;
2494
2495     case elfcpp::R_386_8:
2496     case elfcpp::R_386_PC8:
2497       return 1;
2498
2499       // These are relocations which should only be seen by the
2500       // dynamic linker, and should never be seen here.
2501     case elfcpp::R_386_COPY:
2502     case elfcpp::R_386_GLOB_DAT:
2503     case elfcpp::R_386_JUMP_SLOT:
2504     case elfcpp::R_386_RELATIVE:
2505     case elfcpp::R_386_TLS_TPOFF:
2506     case elfcpp::R_386_TLS_DTPMOD32:
2507     case elfcpp::R_386_TLS_DTPOFF32:
2508     case elfcpp::R_386_TLS_TPOFF32:
2509     case elfcpp::R_386_TLS_DESC:
2510       object->error(_("unexpected reloc %u in object file"), r_type);
2511       return 0;
2512
2513     case elfcpp::R_386_32PLT:
2514     case elfcpp::R_386_TLS_GD_32:
2515     case elfcpp::R_386_TLS_GD_PUSH:
2516     case elfcpp::R_386_TLS_GD_CALL:
2517     case elfcpp::R_386_TLS_GD_POP:
2518     case elfcpp::R_386_TLS_LDM_32:
2519     case elfcpp::R_386_TLS_LDM_PUSH:
2520     case elfcpp::R_386_TLS_LDM_CALL:
2521     case elfcpp::R_386_TLS_LDM_POP:
2522     case elfcpp::R_386_USED_BY_INTEL_200:
2523     default:
2524       object->error(_("unsupported reloc %u in object file"), r_type);
2525       return 0;
2526     }
2527 }
2528
2529 // Scan the relocs during a relocatable link.
2530
2531 void
2532 Target_i386::scan_relocatable_relocs(Symbol_table* symtab,
2533                                      Layout* layout,
2534                                      Sized_relobj<32, false>* object,
2535                                      unsigned int data_shndx,
2536                                      unsigned int sh_type,
2537                                      const unsigned char* prelocs,
2538                                      size_t reloc_count,
2539                                      Output_section* output_section,
2540                                      bool needs_special_offset_handling,
2541                                      size_t local_symbol_count,
2542                                      const unsigned char* plocal_symbols,
2543                                      Relocatable_relocs* rr)
2544 {
2545   gold_assert(sh_type == elfcpp::SHT_REL);
2546
2547   typedef gold::Default_scan_relocatable_relocs<elfcpp::SHT_REL,
2548     Relocatable_size_for_reloc> Scan_relocatable_relocs;
2549
2550   gold::scan_relocatable_relocs<32, false, elfcpp::SHT_REL,
2551       Scan_relocatable_relocs>(
2552     symtab,
2553     layout,
2554     object,
2555     data_shndx,
2556     prelocs,
2557     reloc_count,
2558     output_section,
2559     needs_special_offset_handling,
2560     local_symbol_count,
2561     plocal_symbols,
2562     rr);
2563 }
2564
2565 // Relocate a section during a relocatable link.
2566
2567 void
2568 Target_i386::relocate_for_relocatable(
2569     const Relocate_info<32, false>* relinfo,
2570     unsigned int sh_type,
2571     const unsigned char* prelocs,
2572     size_t reloc_count,
2573     Output_section* output_section,
2574     off_t offset_in_output_section,
2575     const Relocatable_relocs* rr,
2576     unsigned char* view,
2577     elfcpp::Elf_types<32>::Elf_Addr view_address,
2578     section_size_type view_size,
2579     unsigned char* reloc_view,
2580     section_size_type reloc_view_size)
2581 {
2582   gold_assert(sh_type == elfcpp::SHT_REL);
2583
2584   gold::relocate_for_relocatable<32, false, elfcpp::SHT_REL>(
2585     relinfo,
2586     prelocs,
2587     reloc_count,
2588     output_section,
2589     offset_in_output_section,
2590     rr,
2591     view,
2592     view_address,
2593     view_size,
2594     reloc_view,
2595     reloc_view_size);
2596 }
2597
2598 // Return the value to use for a dynamic which requires special
2599 // treatment.  This is how we support equality comparisons of function
2600 // pointers across shared library boundaries, as described in the
2601 // processor specific ABI supplement.
2602
2603 uint64_t
2604 Target_i386::do_dynsym_value(const Symbol* gsym) const
2605 {
2606   gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset());
2607   return this->plt_section()->address() + gsym->plt_offset();
2608 }
2609
2610 // Return a string used to fill a code section with nops to take up
2611 // the specified length.
2612
2613 std::string
2614 Target_i386::do_code_fill(section_size_type length) const
2615 {
2616   if (length >= 16)
2617     {
2618       // Build a jmp instruction to skip over the bytes.
2619       unsigned char jmp[5];
2620       jmp[0] = 0xe9;
2621       elfcpp::Swap_unaligned<32, false>::writeval(jmp + 1, length - 5);
2622       return (std::string(reinterpret_cast<char*>(&jmp[0]), 5)
2623               + std::string(length - 5, '\0'));
2624     }
2625
2626   // Nop sequences of various lengths.
2627   const char nop1[1] = { 0x90 };                   // nop
2628   const char nop2[2] = { 0x66, 0x90 };             // xchg %ax %ax
2629   const char nop3[3] = { 0x8d, 0x76, 0x00 };       // leal 0(%esi),%esi
2630   const char nop4[4] = { 0x8d, 0x74, 0x26, 0x00};  // leal 0(%esi,1),%esi
2631   const char nop5[5] = { 0x90, 0x8d, 0x74, 0x26,   // nop
2632                          0x00 };                   // leal 0(%esi,1),%esi
2633   const char nop6[6] = { 0x8d, 0xb6, 0x00, 0x00,   // leal 0L(%esi),%esi
2634                          0x00, 0x00 };
2635   const char nop7[7] = { 0x8d, 0xb4, 0x26, 0x00,   // leal 0L(%esi,1),%esi
2636                          0x00, 0x00, 0x00 };
2637   const char nop8[8] = { 0x90, 0x8d, 0xb4, 0x26,   // nop
2638                          0x00, 0x00, 0x00, 0x00 }; // leal 0L(%esi,1),%esi
2639   const char nop9[9] = { 0x89, 0xf6, 0x8d, 0xbc,   // movl %esi,%esi
2640                          0x27, 0x00, 0x00, 0x00,   // leal 0L(%edi,1),%edi
2641                          0x00 };
2642   const char nop10[10] = { 0x8d, 0x76, 0x00, 0x8d, // leal 0(%esi),%esi
2643                            0xbc, 0x27, 0x00, 0x00, // leal 0L(%edi,1),%edi
2644                            0x00, 0x00 };
2645   const char nop11[11] = { 0x8d, 0x74, 0x26, 0x00, // leal 0(%esi,1),%esi
2646                            0x8d, 0xbc, 0x27, 0x00, // leal 0L(%edi,1),%edi
2647                            0x00, 0x00, 0x00 };
2648   const char nop12[12] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2649                            0x00, 0x00, 0x8d, 0xbf, // leal 0L(%edi),%edi
2650                            0x00, 0x00, 0x00, 0x00 };
2651   const char nop13[13] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2652                            0x00, 0x00, 0x8d, 0xbc, // leal 0L(%edi,1),%edi
2653                            0x27, 0x00, 0x00, 0x00,
2654                            0x00 };
2655   const char nop14[14] = { 0x8d, 0xb4, 0x26, 0x00, // leal 0L(%esi,1),%esi
2656                            0x00, 0x00, 0x00, 0x8d, // leal 0L(%edi,1),%edi
2657                            0xbc, 0x27, 0x00, 0x00,
2658                            0x00, 0x00 };
2659   const char nop15[15] = { 0xeb, 0x0d, 0x90, 0x90, // jmp .+15
2660                            0x90, 0x90, 0x90, 0x90, // nop,nop,nop,...
2661                            0x90, 0x90, 0x90, 0x90,
2662                            0x90, 0x90, 0x90 };
2663
2664   const char* nops[16] = {
2665     NULL,
2666     nop1, nop2, nop3, nop4, nop5, nop6, nop7,
2667     nop8, nop9, nop10, nop11, nop12, nop13, nop14, nop15
2668   };
2669
2670   return std::string(nops[length], length);
2671 }
2672
2673 // FNOFFSET in section SHNDX in OBJECT is the start of a function
2674 // compiled with -fstack-split.  The function calls non-stack-split
2675 // code.  We have to change the function so that it always ensures
2676 // that it has enough stack space to run some random function.
2677
2678 void
2679 Target_i386::do_calls_non_split(Relobj* object, unsigned int shndx,
2680                                 section_offset_type fnoffset,
2681                                 section_size_type fnsize,
2682                                 unsigned char* view,
2683                                 section_size_type view_size,
2684                                 std::string* from,
2685                                 std::string* to) const
2686 {
2687   // The function starts with a comparison of the stack pointer and a
2688   // field in the TCB.  This is followed by a jump.
2689
2690   // cmp %gs:NN,%esp
2691   if (this->match_view(view, view_size, fnoffset, "\x65\x3b\x25", 3)
2692       && fnsize > 7)
2693     {
2694       // We will call __morestack if the carry flag is set after this
2695       // comparison.  We turn the comparison into an stc instruction
2696       // and some nops.
2697       view[fnoffset] = '\xf9';
2698       this->set_view_to_nop(view, view_size, fnoffset + 1, 6);
2699     }
2700   // lea NN(%esp),%ecx
2701   else if (this->match_view(view, view_size, fnoffset, "\x8d\x8c\x24", 3)
2702            && fnsize > 7)
2703     {
2704       // This is loading an offset from the stack pointer for a
2705       // comparison.  The offset is negative, so we decrease the
2706       // offset by the amount of space we need for the stack.  This
2707       // means we will avoid calling __morestack if there happens to
2708       // be plenty of space on the stack already.
2709       unsigned char* pval = view + fnoffset + 3;
2710       uint32_t val = elfcpp::Swap_unaligned<32, false>::readval(pval);
2711       val -= parameters->options().split_stack_adjust_size();
2712       elfcpp::Swap_unaligned<32, false>::writeval(pval, val);
2713     }
2714   else
2715     {
2716       if (!object->has_no_split_stack())
2717         object->error(_("failed to match split-stack sequence at "
2718                         "section %u offset %0zx"),
2719                       shndx, fnoffset);
2720       return;
2721     }
2722
2723   // We have to change the function so that it calls
2724   // __morestack_non_split instead of __morestack.  The former will
2725   // allocate additional stack space.
2726   *from = "__morestack";
2727   *to = "__morestack_non_split";
2728 }
2729
2730 // The selector for i386 object files.
2731
2732 class Target_selector_i386 : public Target_selector_freebsd
2733 {
2734 public:
2735   Target_selector_i386()
2736     : Target_selector_freebsd(elfcpp::EM_386, 32, false,
2737                               "elf32-i386", "elf32-i386-freebsd")
2738   { }
2739
2740   Target*
2741   do_instantiate_target()
2742   { return new Target_i386(); }
2743 };
2744
2745 Target_selector_i386 target_selector_i386;
2746
2747 } // End anonymous namespace.