1 // i386.cc -- i386 target support for gold.
3 // Copyright (C) 2006-2015 Free Software Foundation, Inc.
4 // Written by Ian Lance Taylor <iant@google.com>.
6 // This file is part of gold.
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.
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.
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.
29 #include "parameters.h"
36 #include "copy-relocs.h"
38 #include "target-reloc.h"
39 #include "target-select.h"
50 // A class to handle the .got.plt section.
52 class Output_data_got_plt_i386 : public Output_section_data_build
55 Output_data_got_plt_i386(Layout* layout)
56 : Output_section_data_build(4),
61 // Write out the PLT data.
63 do_write(Output_file*);
65 // Write to a map file.
67 do_print_to_mapfile(Mapfile* mapfile) const
68 { mapfile->print_output_data(this, "** GOT PLT"); }
71 // A pointer to the Layout class, so that we can find the .dynamic
72 // section when we write out the GOT PLT section.
76 // A class to handle the PLT data.
77 // This is an abstract base class that handles most of the linker details
78 // but does not know the actual contents of PLT entries. The derived
79 // classes below fill in those details.
81 class Output_data_plt_i386 : public Output_section_data
84 typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, false> Reloc_section;
86 Output_data_plt_i386(Layout*, uint64_t addralign,
87 Output_data_got_plt_i386*, Output_data_space*);
89 // Add an entry to the PLT.
91 add_entry(Symbol_table*, Layout*, Symbol* gsym);
93 // Add an entry to the PLT for a local STT_GNU_IFUNC symbol.
95 add_local_ifunc_entry(Symbol_table*, Layout*,
96 Sized_relobj_file<32, false>* relobj,
97 unsigned int local_sym_index);
99 // Return the .rel.plt section data.
102 { return this->rel_; }
104 // Return where the TLS_DESC relocations should go.
106 rel_tls_desc(Layout*);
108 // Return where the IRELATIVE relocations should go.
110 rel_irelative(Symbol_table*, Layout*);
112 // Return whether we created a section for IRELATIVE relocations.
114 has_irelative_section() const
115 { return this->irelative_rel_ != NULL; }
117 // Return the number of PLT entries.
120 { return this->count_ + this->irelative_count_; }
122 // Return the offset of the first non-reserved PLT entry.
124 first_plt_entry_offset()
125 { return this->get_plt_entry_size(); }
127 // Return the size of a PLT entry.
129 get_plt_entry_size() const
130 { return this->do_get_plt_entry_size(); }
132 // Return the PLT address to use for a global symbol.
134 address_for_global(const Symbol*);
136 // Return the PLT address to use for a local symbol.
138 address_for_local(const Relobj*, unsigned int symndx);
140 // Add .eh_frame information for the PLT.
142 add_eh_frame(Layout* layout)
143 { this->do_add_eh_frame(layout); }
146 // Fill the first PLT entry, given the pointer to the PLT section data
147 // and the runtime address of the GOT.
149 fill_first_plt_entry(unsigned char* pov,
150 elfcpp::Elf_types<32>::Elf_Addr got_address)
151 { this->do_fill_first_plt_entry(pov, got_address); }
153 // Fill a normal PLT entry, given the pointer to the entry's data in the
154 // section, the runtime address of the GOT, the offset into the GOT of
155 // the corresponding slot, the offset into the relocation section of the
156 // corresponding reloc, and the offset of this entry within the whole
157 // PLT. Return the offset from this PLT entry's runtime address that
158 // should be used to compute the initial value of the GOT slot.
160 fill_plt_entry(unsigned char* pov,
161 elfcpp::Elf_types<32>::Elf_Addr got_address,
162 unsigned int got_offset,
163 unsigned int plt_offset,
164 unsigned int plt_rel_offset)
166 return this->do_fill_plt_entry(pov, got_address, got_offset,
167 plt_offset, plt_rel_offset);
171 do_get_plt_entry_size() const = 0;
174 do_fill_first_plt_entry(unsigned char* pov,
175 elfcpp::Elf_types<32>::Elf_Addr got_address) = 0;
178 do_fill_plt_entry(unsigned char* pov,
179 elfcpp::Elf_types<32>::Elf_Addr got_address,
180 unsigned int got_offset,
181 unsigned int plt_offset,
182 unsigned int plt_rel_offset) = 0;
185 do_add_eh_frame(Layout*) = 0;
188 do_adjust_output_section(Output_section* os);
190 // Write to a map file.
192 do_print_to_mapfile(Mapfile* mapfile) const
193 { mapfile->print_output_data(this, _("** PLT")); }
195 // The .eh_frame unwind information for the PLT.
196 // The CIE is common across variants of the PLT format.
197 static const int plt_eh_frame_cie_size = 16;
198 static const unsigned char plt_eh_frame_cie[plt_eh_frame_cie_size];
201 // Set the final size.
203 set_final_data_size()
205 this->set_data_size((this->count_ + this->irelative_count_ + 1)
206 * this->get_plt_entry_size());
209 // Write out the PLT data.
211 do_write(Output_file*);
213 // We keep a list of global STT_GNU_IFUNC symbols, each with its
214 // offset in the GOT.
218 unsigned int got_offset;
221 // We keep a list of local STT_GNU_IFUNC symbols, each with its
222 // offset in the GOT.
225 Sized_relobj_file<32, false>* object;
226 unsigned int local_sym_index;
227 unsigned int got_offset;
230 // The reloc section.
232 // The TLS_DESC relocations, if necessary. These must follow the
233 // regular PLT relocs.
234 Reloc_section* tls_desc_rel_;
235 // The IRELATIVE relocations, if necessary. These must follow the
236 // regular relocatoins and the TLS_DESC relocations.
237 Reloc_section* irelative_rel_;
238 // The .got.plt section.
239 Output_data_got_plt_i386* got_plt_;
240 // The part of the .got.plt section used for IRELATIVE relocs.
241 Output_data_space* got_irelative_;
242 // The number of PLT entries.
244 // Number of PLT entries with R_386_IRELATIVE relocs. These follow
245 // the regular PLT entries.
246 unsigned int irelative_count_;
247 // Global STT_GNU_IFUNC symbols.
248 std::vector<Global_ifunc> global_ifuncs_;
249 // Local STT_GNU_IFUNC symbols.
250 std::vector<Local_ifunc> local_ifuncs_;
253 // This is an abstract class for the standard PLT layout.
254 // The derived classes below handle the actual PLT contents
255 // for the executable (non-PIC) and shared-library (PIC) cases.
256 // The unwind information is uniform across those two, so it's here.
258 class Output_data_plt_i386_standard : public Output_data_plt_i386
261 Output_data_plt_i386_standard(Layout* layout,
262 Output_data_got_plt_i386* got_plt,
263 Output_data_space* got_irelative)
264 : Output_data_plt_i386(layout, plt_entry_size, got_plt, got_irelative)
269 do_get_plt_entry_size() const
270 { return plt_entry_size; }
273 do_add_eh_frame(Layout* layout)
275 layout->add_eh_frame_for_plt(this, plt_eh_frame_cie, plt_eh_frame_cie_size,
276 plt_eh_frame_fde, plt_eh_frame_fde_size);
279 // The size of an entry in the PLT.
280 static const int plt_entry_size = 16;
282 // The .eh_frame unwind information for the PLT.
283 static const int plt_eh_frame_fde_size = 32;
284 static const unsigned char plt_eh_frame_fde[plt_eh_frame_fde_size];
287 // Actually fill the PLT contents for an executable (non-PIC).
289 class Output_data_plt_i386_exec : public Output_data_plt_i386_standard
292 Output_data_plt_i386_exec(Layout* layout,
293 Output_data_got_plt_i386* got_plt,
294 Output_data_space* got_irelative)
295 : Output_data_plt_i386_standard(layout, got_plt, got_irelative)
300 do_fill_first_plt_entry(unsigned char* pov,
301 elfcpp::Elf_types<32>::Elf_Addr got_address);
304 do_fill_plt_entry(unsigned char* pov,
305 elfcpp::Elf_types<32>::Elf_Addr got_address,
306 unsigned int got_offset,
307 unsigned int plt_offset,
308 unsigned int plt_rel_offset);
311 // The first entry in the PLT for an executable.
312 static const unsigned char first_plt_entry[plt_entry_size];
314 // Other entries in the PLT for an executable.
315 static const unsigned char plt_entry[plt_entry_size];
318 // Actually fill the PLT contents for a shared library (PIC).
320 class Output_data_plt_i386_dyn : public Output_data_plt_i386_standard
323 Output_data_plt_i386_dyn(Layout* layout,
324 Output_data_got_plt_i386* got_plt,
325 Output_data_space* got_irelative)
326 : Output_data_plt_i386_standard(layout, got_plt, got_irelative)
331 do_fill_first_plt_entry(unsigned char* pov, elfcpp::Elf_types<32>::Elf_Addr);
334 do_fill_plt_entry(unsigned char* pov,
335 elfcpp::Elf_types<32>::Elf_Addr,
336 unsigned int got_offset,
337 unsigned int plt_offset,
338 unsigned int plt_rel_offset);
341 // The first entry in the PLT for a shared object.
342 static const unsigned char first_plt_entry[plt_entry_size];
344 // Other entries in the PLT for a shared object.
345 static const unsigned char plt_entry[plt_entry_size];
348 // The i386 target class.
349 // TLS info comes from
350 // http://people.redhat.com/drepper/tls.pdf
351 // http://www.lsd.ic.unicamp.br/~oliva/writeups/TLS/RFC-TLSDESC-x86.txt
353 class Target_i386 : public Sized_target<32, false>
356 typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, false> Reloc_section;
358 Target_i386(const Target::Target_info* info = &i386_info)
359 : Sized_target<32, false>(info),
360 got_(NULL), plt_(NULL), got_plt_(NULL), got_irelative_(NULL),
361 got_tlsdesc_(NULL), global_offset_table_(NULL), rel_dyn_(NULL),
362 rel_irelative_(NULL), copy_relocs_(elfcpp::R_386_COPY),
363 got_mod_index_offset_(-1U), tls_base_symbol_defined_(false)
366 // Process the relocations to determine unreferenced sections for
367 // garbage collection.
369 gc_process_relocs(Symbol_table* symtab,
371 Sized_relobj_file<32, false>* object,
372 unsigned int data_shndx,
373 unsigned int sh_type,
374 const unsigned char* prelocs,
376 Output_section* output_section,
377 bool needs_special_offset_handling,
378 size_t local_symbol_count,
379 const unsigned char* plocal_symbols);
381 // Scan the relocations to look for symbol adjustments.
383 scan_relocs(Symbol_table* symtab,
385 Sized_relobj_file<32, false>* object,
386 unsigned int data_shndx,
387 unsigned int sh_type,
388 const unsigned char* prelocs,
390 Output_section* output_section,
391 bool needs_special_offset_handling,
392 size_t local_symbol_count,
393 const unsigned char* plocal_symbols);
395 // Finalize the sections.
397 do_finalize_sections(Layout*, const Input_objects*, Symbol_table*);
399 // Return the value to use for a dynamic which requires special
402 do_dynsym_value(const Symbol*) const;
404 // Relocate a section.
406 relocate_section(const Relocate_info<32, false>*,
407 unsigned int sh_type,
408 const unsigned char* prelocs,
410 Output_section* output_section,
411 bool needs_special_offset_handling,
413 elfcpp::Elf_types<32>::Elf_Addr view_address,
414 section_size_type view_size,
415 const Reloc_symbol_changes*);
417 // Scan the relocs during a relocatable link.
419 scan_relocatable_relocs(Symbol_table* symtab,
421 Sized_relobj_file<32, false>* object,
422 unsigned int data_shndx,
423 unsigned int sh_type,
424 const unsigned char* prelocs,
426 Output_section* output_section,
427 bool needs_special_offset_handling,
428 size_t local_symbol_count,
429 const unsigned char* plocal_symbols,
430 Relocatable_relocs*);
432 // Emit relocations for a section.
434 relocate_relocs(const Relocate_info<32, false>*,
435 unsigned int sh_type,
436 const unsigned char* prelocs,
438 Output_section* output_section,
439 elfcpp::Elf_types<32>::Elf_Off offset_in_output_section,
440 const Relocatable_relocs*,
442 elfcpp::Elf_types<32>::Elf_Addr view_address,
443 section_size_type view_size,
444 unsigned char* reloc_view,
445 section_size_type reloc_view_size);
447 // Return a string used to fill a code section with nops.
449 do_code_fill(section_size_type length) const;
451 // Return whether SYM is defined by the ABI.
453 do_is_defined_by_abi(const Symbol* sym) const
454 { return strcmp(sym->name(), "___tls_get_addr") == 0; }
456 // Return whether a symbol name implies a local label. The UnixWare
457 // 2.1 cc generates temporary symbols that start with .X, so we
458 // recognize them here. FIXME: do other SVR4 compilers also use .X?.
459 // If so, we should move the .X recognition into
460 // Target::do_is_local_label_name.
462 do_is_local_label_name(const char* name) const
464 if (name[0] == '.' && name[1] == 'X')
466 return Target::do_is_local_label_name(name);
469 // Return the PLT address to use for a global symbol.
471 do_plt_address_for_global(const Symbol* gsym) const
472 { return this->plt_section()->address_for_global(gsym); }
475 do_plt_address_for_local(const Relobj* relobj, unsigned int symndx) const
476 { return this->plt_section()->address_for_local(relobj, symndx); }
478 // We can tell whether we take the address of a function.
480 do_can_check_for_function_pointers() const
483 // Return the base for a DW_EH_PE_datarel encoding.
485 do_ehframe_datarel_base() const;
487 // Return whether SYM is call to a non-split function.
489 do_is_call_to_non_split(const Symbol* sym, unsigned int) const;
491 // Adjust -fsplit-stack code which calls non-split-stack code.
493 do_calls_non_split(Relobj* object, unsigned int shndx,
494 section_offset_type fnoffset, section_size_type fnsize,
495 unsigned char* view, section_size_type view_size,
496 std::string* from, std::string* to) const;
498 // Return the size of the GOT section.
502 gold_assert(this->got_ != NULL);
503 return this->got_->data_size();
506 // Return the number of entries in the GOT.
508 got_entry_count() const
510 if (this->got_ == NULL)
512 return this->got_size() / 4;
515 // Return the number of entries in the PLT.
517 plt_entry_count() const;
519 // Return the offset of the first non-reserved PLT entry.
521 first_plt_entry_offset() const;
523 // Return the size of each PLT entry.
525 plt_entry_size() const;
528 // Instantiate the plt_ member.
529 // This chooses the right PLT flavor for an executable or a shared object.
530 Output_data_plt_i386*
531 make_data_plt(Layout* layout,
532 Output_data_got_plt_i386* got_plt,
533 Output_data_space* got_irelative,
535 { return this->do_make_data_plt(layout, got_plt, got_irelative, dyn); }
537 virtual Output_data_plt_i386*
538 do_make_data_plt(Layout* layout,
539 Output_data_got_plt_i386* got_plt,
540 Output_data_space* got_irelative,
544 return new Output_data_plt_i386_dyn(layout, got_plt, got_irelative);
546 return new Output_data_plt_i386_exec(layout, got_plt, got_irelative);
550 // The class which scans relocations.
555 get_reference_flags(unsigned int r_type);
558 local(Symbol_table* symtab, Layout* layout, Target_i386* target,
559 Sized_relobj_file<32, false>* object,
560 unsigned int data_shndx,
561 Output_section* output_section,
562 const elfcpp::Rel<32, false>& reloc, unsigned int r_type,
563 const elfcpp::Sym<32, false>& lsym,
567 global(Symbol_table* symtab, Layout* layout, Target_i386* target,
568 Sized_relobj_file<32, false>* object,
569 unsigned int data_shndx,
570 Output_section* output_section,
571 const elfcpp::Rel<32, false>& reloc, unsigned int r_type,
575 local_reloc_may_be_function_pointer(Symbol_table* symtab, Layout* layout,
577 Sized_relobj_file<32, false>* object,
578 unsigned int data_shndx,
579 Output_section* output_section,
580 const elfcpp::Rel<32, false>& reloc,
582 const elfcpp::Sym<32, false>& lsym);
585 global_reloc_may_be_function_pointer(Symbol_table* symtab, Layout* layout,
587 Sized_relobj_file<32, false>* object,
588 unsigned int data_shndx,
589 Output_section* output_section,
590 const elfcpp::Rel<32, false>& reloc,
595 possible_function_pointer_reloc(unsigned int r_type);
598 reloc_needs_plt_for_ifunc(Sized_relobj_file<32, false>*,
599 unsigned int r_type);
602 unsupported_reloc_local(Sized_relobj_file<32, false>*, unsigned int r_type);
605 unsupported_reloc_global(Sized_relobj_file<32, false>*, unsigned int r_type,
609 // The class which implements relocation.
614 : skip_call_tls_get_addr_(false),
615 local_dynamic_type_(LOCAL_DYNAMIC_NONE)
620 if (this->skip_call_tls_get_addr_)
622 // FIXME: This needs to specify the location somehow.
623 gold_error(_("missing expected TLS relocation"));
627 // Return whether the static relocation needs to be applied.
629 should_apply_static_reloc(const Sized_symbol<32>* gsym,
632 Output_section* output_section);
634 // Do a relocation. Return false if the caller should not issue
635 // any warnings about this relocation.
637 relocate(const Relocate_info<32, false>*, Target_i386*, Output_section*,
638 size_t relnum, const elfcpp::Rel<32, false>&,
639 unsigned int r_type, const Sized_symbol<32>*,
640 const Symbol_value<32>*,
641 unsigned char*, elfcpp::Elf_types<32>::Elf_Addr,
645 // Do a TLS relocation.
647 relocate_tls(const Relocate_info<32, false>*, Target_i386* target,
648 size_t relnum, const elfcpp::Rel<32, false>&,
649 unsigned int r_type, const Sized_symbol<32>*,
650 const Symbol_value<32>*,
651 unsigned char*, elfcpp::Elf_types<32>::Elf_Addr,
654 // Do a TLS General-Dynamic to Initial-Exec transition.
656 tls_gd_to_ie(const Relocate_info<32, false>*, size_t relnum,
657 Output_segment* tls_segment,
658 const elfcpp::Rel<32, false>&, unsigned int r_type,
659 elfcpp::Elf_types<32>::Elf_Addr value,
661 section_size_type view_size);
663 // Do a TLS General-Dynamic to Local-Exec transition.
665 tls_gd_to_le(const Relocate_info<32, false>*, size_t relnum,
666 Output_segment* tls_segment,
667 const elfcpp::Rel<32, false>&, unsigned int r_type,
668 elfcpp::Elf_types<32>::Elf_Addr value,
670 section_size_type view_size);
672 // Do a TLS_GOTDESC or TLS_DESC_CALL General-Dynamic to Initial-Exec
675 tls_desc_gd_to_ie(const Relocate_info<32, false>*, size_t relnum,
676 Output_segment* tls_segment,
677 const elfcpp::Rel<32, false>&, unsigned int r_type,
678 elfcpp::Elf_types<32>::Elf_Addr value,
680 section_size_type view_size);
682 // Do a TLS_GOTDESC or TLS_DESC_CALL General-Dynamic to Local-Exec
685 tls_desc_gd_to_le(const Relocate_info<32, false>*, size_t relnum,
686 Output_segment* tls_segment,
687 const elfcpp::Rel<32, false>&, unsigned int r_type,
688 elfcpp::Elf_types<32>::Elf_Addr value,
690 section_size_type view_size);
692 // Do a TLS Local-Dynamic to Local-Exec transition.
694 tls_ld_to_le(const Relocate_info<32, false>*, size_t relnum,
695 Output_segment* tls_segment,
696 const elfcpp::Rel<32, false>&, unsigned int r_type,
697 elfcpp::Elf_types<32>::Elf_Addr value,
699 section_size_type view_size);
701 // Do a TLS Initial-Exec to Local-Exec transition.
703 tls_ie_to_le(const Relocate_info<32, false>*, size_t relnum,
704 Output_segment* tls_segment,
705 const elfcpp::Rel<32, false>&, unsigned int r_type,
706 elfcpp::Elf_types<32>::Elf_Addr value,
708 section_size_type view_size);
710 // We need to keep track of which type of local dynamic relocation
711 // we have seen, so that we can optimize R_386_TLS_LDO_32 correctly.
712 enum Local_dynamic_type
719 // This is set if we should skip the next reloc, which should be a
720 // PLT32 reloc against ___tls_get_addr.
721 bool skip_call_tls_get_addr_;
722 // The type of local dynamic relocation we have seen in the section
723 // being relocated, if any.
724 Local_dynamic_type local_dynamic_type_;
727 // A class which returns the size required for a relocation type,
728 // used while scanning relocs during a relocatable link.
729 class Relocatable_size_for_reloc
733 get_size_for_reloc(unsigned int, Relobj*);
736 // Adjust TLS relocation type based on the options and whether this
737 // is a local symbol.
738 static tls::Tls_optimization
739 optimize_tls_reloc(bool is_final, int r_type);
741 // Check if relocation against this symbol is a candidate for
743 // mov foo@GOT(%reg), %reg
745 // lea foo@GOTOFF(%reg), %reg.
747 can_convert_mov_to_lea(const Symbol* gsym)
749 gold_assert(gsym != NULL);
750 return (gsym->type() != elfcpp::STT_GNU_IFUNC
751 && !gsym->is_undefined ()
752 && !gsym->is_from_dynobj()
753 && !gsym->is_preemptible()
754 && (!parameters->options().shared()
755 || (gsym->visibility() != elfcpp::STV_DEFAULT
756 && gsym->visibility() != elfcpp::STV_PROTECTED)
757 || parameters->options().Bsymbolic())
758 && strcmp(gsym->name(), "_DYNAMIC") != 0);
761 // Get the GOT section, creating it if necessary.
762 Output_data_got<32, false>*
763 got_section(Symbol_table*, Layout*);
765 // Get the GOT PLT section.
766 Output_data_got_plt_i386*
767 got_plt_section() const
769 gold_assert(this->got_plt_ != NULL);
770 return this->got_plt_;
773 // Get the GOT section for TLSDESC entries.
774 Output_data_got<32, false>*
775 got_tlsdesc_section() const
777 gold_assert(this->got_tlsdesc_ != NULL);
778 return this->got_tlsdesc_;
781 // Create the PLT section.
783 make_plt_section(Symbol_table* symtab, Layout* layout);
785 // Create a PLT entry for a global symbol.
787 make_plt_entry(Symbol_table*, Layout*, Symbol*);
789 // Create a PLT entry for a local STT_GNU_IFUNC symbol.
791 make_local_ifunc_plt_entry(Symbol_table*, Layout*,
792 Sized_relobj_file<32, false>* relobj,
793 unsigned int local_sym_index);
795 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
797 define_tls_base_symbol(Symbol_table*, Layout*);
799 // Create a GOT entry for the TLS module index.
801 got_mod_index_entry(Symbol_table* symtab, Layout* layout,
802 Sized_relobj_file<32, false>* object);
804 // Get the PLT section.
805 Output_data_plt_i386*
808 gold_assert(this->plt_ != NULL);
812 // Get the dynamic reloc section, creating it if necessary.
814 rel_dyn_section(Layout*);
816 // Get the section to use for TLS_DESC relocations.
818 rel_tls_desc_section(Layout*) const;
820 // Get the section to use for IRELATIVE relocations.
822 rel_irelative_section(Layout*);
824 // Add a potential copy relocation.
826 copy_reloc(Symbol_table* symtab, Layout* layout,
827 Sized_relobj_file<32, false>* object,
828 unsigned int shndx, Output_section* output_section,
829 Symbol* sym, const elfcpp::Rel<32, false>& reloc)
831 this->copy_relocs_.copy_reloc(symtab, layout,
832 symtab->get_sized_symbol<32>(sym),
833 object, shndx, output_section, reloc,
834 this->rel_dyn_section(layout));
837 // Information about this specific target which we pass to the
838 // general Target structure.
839 static const Target::Target_info i386_info;
841 // The types of GOT entries needed for this platform.
842 // These values are exposed to the ABI in an incremental link.
843 // Do not renumber existing values without changing the version
844 // number of the .gnu_incremental_inputs section.
847 GOT_TYPE_STANDARD = 0, // GOT entry for a regular symbol
848 GOT_TYPE_TLS_NOFFSET = 1, // GOT entry for negative TLS offset
849 GOT_TYPE_TLS_OFFSET = 2, // GOT entry for positive TLS offset
850 GOT_TYPE_TLS_PAIR = 3, // GOT entry for TLS module/offset pair
851 GOT_TYPE_TLS_DESC = 4 // GOT entry for TLS_DESC pair
855 Output_data_got<32, false>* got_;
857 Output_data_plt_i386* plt_;
858 // The GOT PLT section.
859 Output_data_got_plt_i386* got_plt_;
860 // The GOT section for IRELATIVE relocations.
861 Output_data_space* got_irelative_;
862 // The GOT section for TLSDESC relocations.
863 Output_data_got<32, false>* got_tlsdesc_;
864 // The _GLOBAL_OFFSET_TABLE_ symbol.
865 Symbol* global_offset_table_;
866 // The dynamic reloc section.
867 Reloc_section* rel_dyn_;
868 // The section to use for IRELATIVE relocs.
869 Reloc_section* rel_irelative_;
870 // Relocs saved to avoid a COPY reloc.
871 Copy_relocs<elfcpp::SHT_REL, 32, false> copy_relocs_;
872 // Offset of the GOT entry for the TLS module index.
873 unsigned int got_mod_index_offset_;
874 // True if the _TLS_MODULE_BASE_ symbol has been defined.
875 bool tls_base_symbol_defined_;
878 const Target::Target_info Target_i386::i386_info =
881 false, // is_big_endian
882 elfcpp::EM_386, // machine_code
883 false, // has_make_symbol
884 false, // has_resolve
885 true, // has_code_fill
886 true, // is_default_stack_executable
887 true, // can_icf_inline_merge_sections
889 "/usr/lib/libc.so.1", // dynamic_linker
890 0x08048000, // default_text_segment_address
891 0x1000, // abi_pagesize (overridable by -z max-page-size)
892 0x1000, // common_pagesize (overridable by -z common-page-size)
893 false, // isolate_execinstr
895 elfcpp::SHN_UNDEF, // small_common_shndx
896 elfcpp::SHN_UNDEF, // large_common_shndx
897 0, // small_common_section_flags
898 0, // large_common_section_flags
899 NULL, // attributes_section
900 NULL, // attributes_vendor
901 "_start" // entry_symbol_name
904 // Get the GOT section, creating it if necessary.
906 Output_data_got<32, false>*
907 Target_i386::got_section(Symbol_table* symtab, Layout* layout)
909 if (this->got_ == NULL)
911 gold_assert(symtab != NULL && layout != NULL);
913 this->got_ = new Output_data_got<32, false>();
915 // When using -z now, we can treat .got.plt as a relro section.
916 // Without -z now, it is modified after program startup by lazy
918 bool is_got_plt_relro = parameters->options().now();
919 Output_section_order got_order = (is_got_plt_relro
922 Output_section_order got_plt_order = (is_got_plt_relro
924 : ORDER_NON_RELRO_FIRST);
926 layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
928 | elfcpp::SHF_WRITE),
929 this->got_, got_order, true);
931 this->got_plt_ = new Output_data_got_plt_i386(layout);
932 layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
934 | elfcpp::SHF_WRITE),
935 this->got_plt_, got_plt_order,
938 // The first three entries are reserved.
939 this->got_plt_->set_current_data_size(3 * 4);
941 if (!is_got_plt_relro)
943 // Those bytes can go into the relro segment.
944 layout->increase_relro(3 * 4);
947 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
948 this->global_offset_table_ =
949 symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
950 Symbol_table::PREDEFINED,
952 0, 0, elfcpp::STT_OBJECT,
954 elfcpp::STV_HIDDEN, 0,
957 // If there are any IRELATIVE relocations, they get GOT entries
958 // in .got.plt after the jump slot relocations.
959 this->got_irelative_ = new Output_data_space(4, "** GOT IRELATIVE PLT");
960 layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
962 | elfcpp::SHF_WRITE),
963 this->got_irelative_,
964 got_plt_order, is_got_plt_relro);
966 // If there are any TLSDESC relocations, they get GOT entries in
967 // .got.plt after the jump slot entries.
968 this->got_tlsdesc_ = new Output_data_got<32, false>();
969 layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
971 | elfcpp::SHF_WRITE),
973 got_plt_order, is_got_plt_relro);
979 // Get the dynamic reloc section, creating it if necessary.
981 Target_i386::Reloc_section*
982 Target_i386::rel_dyn_section(Layout* layout)
984 if (this->rel_dyn_ == NULL)
986 gold_assert(layout != NULL);
987 this->rel_dyn_ = new Reloc_section(parameters->options().combreloc());
988 layout->add_output_section_data(".rel.dyn", elfcpp::SHT_REL,
989 elfcpp::SHF_ALLOC, this->rel_dyn_,
990 ORDER_DYNAMIC_RELOCS, false);
992 return this->rel_dyn_;
995 // Get the section to use for IRELATIVE relocs, creating it if
996 // necessary. These go in .rel.dyn, but only after all other dynamic
997 // relocations. They need to follow the other dynamic relocations so
998 // that they can refer to global variables initialized by those
1001 Target_i386::Reloc_section*
1002 Target_i386::rel_irelative_section(Layout* layout)
1004 if (this->rel_irelative_ == NULL)
1006 // Make sure we have already create the dynamic reloc section.
1007 this->rel_dyn_section(layout);
1008 this->rel_irelative_ = new Reloc_section(false);
1009 layout->add_output_section_data(".rel.dyn", elfcpp::SHT_REL,
1010 elfcpp::SHF_ALLOC, this->rel_irelative_,
1011 ORDER_DYNAMIC_RELOCS, false);
1012 gold_assert(this->rel_dyn_->output_section()
1013 == this->rel_irelative_->output_section());
1015 return this->rel_irelative_;
1018 // Write the first three reserved words of the .got.plt section.
1019 // The remainder of the section is written while writing the PLT
1020 // in Output_data_plt_i386::do_write.
1023 Output_data_got_plt_i386::do_write(Output_file* of)
1025 // The first entry in the GOT is the address of the .dynamic section
1026 // aka the PT_DYNAMIC segment. The next two entries are reserved.
1027 // We saved space for them when we created the section in
1028 // Target_i386::got_section.
1029 const off_t got_file_offset = this->offset();
1030 gold_assert(this->data_size() >= 12);
1031 unsigned char* const got_view = of->get_output_view(got_file_offset, 12);
1032 Output_section* dynamic = this->layout_->dynamic_section();
1033 uint32_t dynamic_addr = dynamic == NULL ? 0 : dynamic->address();
1034 elfcpp::Swap<32, false>::writeval(got_view, dynamic_addr);
1035 memset(got_view + 4, 0, 8);
1036 of->write_output_view(got_file_offset, 12, got_view);
1039 // Create the PLT section. The ordinary .got section is an argument,
1040 // since we need to refer to the start. We also create our own .got
1041 // section just for PLT entries.
1043 Output_data_plt_i386::Output_data_plt_i386(Layout* layout,
1045 Output_data_got_plt_i386* got_plt,
1046 Output_data_space* got_irelative)
1047 : Output_section_data(addralign),
1048 tls_desc_rel_(NULL), irelative_rel_(NULL), got_plt_(got_plt),
1049 got_irelative_(got_irelative), count_(0), irelative_count_(0),
1050 global_ifuncs_(), local_ifuncs_()
1052 this->rel_ = new Reloc_section(false);
1053 layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL,
1054 elfcpp::SHF_ALLOC, this->rel_,
1055 ORDER_DYNAMIC_PLT_RELOCS, false);
1059 Output_data_plt_i386::do_adjust_output_section(Output_section* os)
1061 // UnixWare sets the entsize of .plt to 4, and so does the old GNU
1062 // linker, and so do we.
1066 // Add an entry to the PLT.
1069 Output_data_plt_i386::add_entry(Symbol_table* symtab, Layout* layout,
1072 gold_assert(!gsym->has_plt_offset());
1074 // Every PLT entry needs a reloc.
1075 if (gsym->type() == elfcpp::STT_GNU_IFUNC
1076 && gsym->can_use_relative_reloc(false))
1078 gsym->set_plt_offset(this->irelative_count_ * this->get_plt_entry_size());
1079 ++this->irelative_count_;
1080 section_offset_type got_offset =
1081 this->got_irelative_->current_data_size();
1082 this->got_irelative_->set_current_data_size(got_offset + 4);
1083 Reloc_section* rel = this->rel_irelative(symtab, layout);
1084 rel->add_symbolless_global_addend(gsym, elfcpp::R_386_IRELATIVE,
1085 this->got_irelative_, got_offset);
1086 struct Global_ifunc gi;
1088 gi.got_offset = got_offset;
1089 this->global_ifuncs_.push_back(gi);
1093 // When setting the PLT offset we skip the initial reserved PLT
1095 gsym->set_plt_offset((this->count_ + 1) * this->get_plt_entry_size());
1099 section_offset_type got_offset = this->got_plt_->current_data_size();
1101 // Every PLT entry needs a GOT entry which points back to the
1102 // PLT entry (this will be changed by the dynamic linker,
1103 // normally lazily when the function is called).
1104 this->got_plt_->set_current_data_size(got_offset + 4);
1106 gsym->set_needs_dynsym_entry();
1107 this->rel_->add_global(gsym, elfcpp::R_386_JUMP_SLOT, this->got_plt_,
1111 // Note that we don't need to save the symbol. The contents of the
1112 // PLT are independent of which symbols are used. The symbols only
1113 // appear in the relocations.
1116 // Add an entry to the PLT for a local STT_GNU_IFUNC symbol. Return
1120 Output_data_plt_i386::add_local_ifunc_entry(
1121 Symbol_table* symtab,
1123 Sized_relobj_file<32, false>* relobj,
1124 unsigned int local_sym_index)
1126 unsigned int plt_offset = this->irelative_count_ * this->get_plt_entry_size();
1127 ++this->irelative_count_;
1129 section_offset_type got_offset = this->got_irelative_->current_data_size();
1131 // Every PLT entry needs a GOT entry which points back to the PLT
1133 this->got_irelative_->set_current_data_size(got_offset + 4);
1135 // Every PLT entry needs a reloc.
1136 Reloc_section* rel = this->rel_irelative(symtab, layout);
1137 rel->add_symbolless_local_addend(relobj, local_sym_index,
1138 elfcpp::R_386_IRELATIVE,
1139 this->got_irelative_, got_offset);
1141 struct Local_ifunc li;
1143 li.local_sym_index = local_sym_index;
1144 li.got_offset = got_offset;
1145 this->local_ifuncs_.push_back(li);
1150 // Return where the TLS_DESC relocations should go, creating it if
1151 // necessary. These follow the JUMP_SLOT relocations.
1153 Output_data_plt_i386::Reloc_section*
1154 Output_data_plt_i386::rel_tls_desc(Layout* layout)
1156 if (this->tls_desc_rel_ == NULL)
1158 this->tls_desc_rel_ = new Reloc_section(false);
1159 layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL,
1160 elfcpp::SHF_ALLOC, this->tls_desc_rel_,
1161 ORDER_DYNAMIC_PLT_RELOCS, false);
1162 gold_assert(this->tls_desc_rel_->output_section()
1163 == this->rel_->output_section());
1165 return this->tls_desc_rel_;
1168 // Return where the IRELATIVE relocations should go in the PLT. These
1169 // follow the JUMP_SLOT and TLS_DESC relocations.
1171 Output_data_plt_i386::Reloc_section*
1172 Output_data_plt_i386::rel_irelative(Symbol_table* symtab, Layout* layout)
1174 if (this->irelative_rel_ == NULL)
1176 // Make sure we have a place for the TLS_DESC relocations, in
1177 // case we see any later on.
1178 this->rel_tls_desc(layout);
1179 this->irelative_rel_ = new Reloc_section(false);
1180 layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL,
1181 elfcpp::SHF_ALLOC, this->irelative_rel_,
1182 ORDER_DYNAMIC_PLT_RELOCS, false);
1183 gold_assert(this->irelative_rel_->output_section()
1184 == this->rel_->output_section());
1186 if (parameters->doing_static_link())
1188 // A statically linked executable will only have a .rel.plt
1189 // section to hold R_386_IRELATIVE relocs for STT_GNU_IFUNC
1190 // symbols. The library will use these symbols to locate
1191 // the IRELATIVE relocs at program startup time.
1192 symtab->define_in_output_data("__rel_iplt_start", NULL,
1193 Symbol_table::PREDEFINED,
1194 this->irelative_rel_, 0, 0,
1195 elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL,
1196 elfcpp::STV_HIDDEN, 0, false, true);
1197 symtab->define_in_output_data("__rel_iplt_end", NULL,
1198 Symbol_table::PREDEFINED,
1199 this->irelative_rel_, 0, 0,
1200 elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL,
1201 elfcpp::STV_HIDDEN, 0, true, true);
1204 return this->irelative_rel_;
1207 // Return the PLT address to use for a global symbol.
1210 Output_data_plt_i386::address_for_global(const Symbol* gsym)
1212 uint64_t offset = 0;
1213 if (gsym->type() == elfcpp::STT_GNU_IFUNC
1214 && gsym->can_use_relative_reloc(false))
1215 offset = (this->count_ + 1) * this->get_plt_entry_size();
1216 return this->address() + offset + gsym->plt_offset();
1219 // Return the PLT address to use for a local symbol. These are always
1220 // IRELATIVE relocs.
1223 Output_data_plt_i386::address_for_local(const Relobj* object,
1226 return (this->address()
1227 + (this->count_ + 1) * this->get_plt_entry_size()
1228 + object->local_plt_offset(r_sym));
1231 // The first entry in the PLT for an executable.
1233 const unsigned char Output_data_plt_i386_exec::first_plt_entry[plt_entry_size] =
1235 0xff, 0x35, // pushl contents of memory address
1236 0, 0, 0, 0, // replaced with address of .got + 4
1237 0xff, 0x25, // jmp indirect
1238 0, 0, 0, 0, // replaced with address of .got + 8
1239 0, 0, 0, 0 // unused
1243 Output_data_plt_i386_exec::do_fill_first_plt_entry(
1245 elfcpp::Elf_types<32>::Elf_Addr got_address)
1247 memcpy(pov, first_plt_entry, plt_entry_size);
1248 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_address + 4);
1249 elfcpp::Swap<32, false>::writeval(pov + 8, got_address + 8);
1252 // The first entry in the PLT for a shared object.
1254 const unsigned char Output_data_plt_i386_dyn::first_plt_entry[plt_entry_size] =
1256 0xff, 0xb3, 4, 0, 0, 0, // pushl 4(%ebx)
1257 0xff, 0xa3, 8, 0, 0, 0, // jmp *8(%ebx)
1258 0, 0, 0, 0 // unused
1262 Output_data_plt_i386_dyn::do_fill_first_plt_entry(
1264 elfcpp::Elf_types<32>::Elf_Addr)
1266 memcpy(pov, first_plt_entry, plt_entry_size);
1269 // Subsequent entries in the PLT for an executable.
1271 const unsigned char Output_data_plt_i386_exec::plt_entry[plt_entry_size] =
1273 0xff, 0x25, // jmp indirect
1274 0, 0, 0, 0, // replaced with address of symbol in .got
1275 0x68, // pushl immediate
1276 0, 0, 0, 0, // replaced with offset into relocation table
1277 0xe9, // jmp relative
1278 0, 0, 0, 0 // replaced with offset to start of .plt
1282 Output_data_plt_i386_exec::do_fill_plt_entry(
1284 elfcpp::Elf_types<32>::Elf_Addr got_address,
1285 unsigned int got_offset,
1286 unsigned int plt_offset,
1287 unsigned int plt_rel_offset)
1289 memcpy(pov, plt_entry, plt_entry_size);
1290 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
1291 got_address + got_offset);
1292 elfcpp::Swap_unaligned<32, false>::writeval(pov + 7, plt_rel_offset);
1293 elfcpp::Swap<32, false>::writeval(pov + 12, - (plt_offset + 12 + 4));
1297 // Subsequent entries in the PLT for a shared object.
1299 const unsigned char Output_data_plt_i386_dyn::plt_entry[plt_entry_size] =
1301 0xff, 0xa3, // jmp *offset(%ebx)
1302 0, 0, 0, 0, // replaced with offset of symbol in .got
1303 0x68, // pushl immediate
1304 0, 0, 0, 0, // replaced with offset into relocation table
1305 0xe9, // jmp relative
1306 0, 0, 0, 0 // replaced with offset to start of .plt
1310 Output_data_plt_i386_dyn::do_fill_plt_entry(unsigned char* pov,
1311 elfcpp::Elf_types<32>::Elf_Addr,
1312 unsigned int got_offset,
1313 unsigned int plt_offset,
1314 unsigned int plt_rel_offset)
1316 memcpy(pov, plt_entry, plt_entry_size);
1317 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_offset);
1318 elfcpp::Swap_unaligned<32, false>::writeval(pov + 7, plt_rel_offset);
1319 elfcpp::Swap<32, false>::writeval(pov + 12, - (plt_offset + 12 + 4));
1323 // The .eh_frame unwind information for the PLT.
1326 Output_data_plt_i386::plt_eh_frame_cie[plt_eh_frame_cie_size] =
1329 'z', // Augmentation: augmentation size included.
1330 'R', // Augmentation: FDE encoding included.
1331 '\0', // End of augmentation string.
1332 1, // Code alignment factor.
1333 0x7c, // Data alignment factor.
1334 8, // Return address column.
1335 1, // Augmentation size.
1336 (elfcpp::DW_EH_PE_pcrel // FDE encoding.
1337 | elfcpp::DW_EH_PE_sdata4),
1338 elfcpp::DW_CFA_def_cfa, 4, 4, // DW_CFA_def_cfa: r4 (esp) ofs 4.
1339 elfcpp::DW_CFA_offset + 8, 1, // DW_CFA_offset: r8 (eip) at cfa-4.
1340 elfcpp::DW_CFA_nop, // Align to 16 bytes.
1345 Output_data_plt_i386_standard::plt_eh_frame_fde[plt_eh_frame_fde_size] =
1347 0, 0, 0, 0, // Replaced with offset to .plt.
1348 0, 0, 0, 0, // Replaced with size of .plt.
1349 0, // Augmentation size.
1350 elfcpp::DW_CFA_def_cfa_offset, 8, // DW_CFA_def_cfa_offset: 8.
1351 elfcpp::DW_CFA_advance_loc + 6, // Advance 6 to __PLT__ + 6.
1352 elfcpp::DW_CFA_def_cfa_offset, 12, // DW_CFA_def_cfa_offset: 12.
1353 elfcpp::DW_CFA_advance_loc + 10, // Advance 10 to __PLT__ + 16.
1354 elfcpp::DW_CFA_def_cfa_expression, // DW_CFA_def_cfa_expression.
1355 11, // Block length.
1356 elfcpp::DW_OP_breg4, 4, // Push %esp + 4.
1357 elfcpp::DW_OP_breg8, 0, // Push %eip.
1358 elfcpp::DW_OP_lit15, // Push 0xf.
1359 elfcpp::DW_OP_and, // & (%eip & 0xf).
1360 elfcpp::DW_OP_lit11, // Push 0xb.
1361 elfcpp::DW_OP_ge, // >= ((%eip & 0xf) >= 0xb)
1362 elfcpp::DW_OP_lit2, // Push 2.
1363 elfcpp::DW_OP_shl, // << (((%eip & 0xf) >= 0xb) << 2)
1364 elfcpp::DW_OP_plus, // + ((((%eip&0xf)>=0xb)<<2)+%esp+4
1365 elfcpp::DW_CFA_nop, // Align to 32 bytes.
1371 // Write out the PLT. This uses the hand-coded instructions above,
1372 // and adjusts them as needed. This is all specified by the i386 ELF
1373 // Processor Supplement.
1376 Output_data_plt_i386::do_write(Output_file* of)
1378 const off_t offset = this->offset();
1379 const section_size_type oview_size =
1380 convert_to_section_size_type(this->data_size());
1381 unsigned char* const oview = of->get_output_view(offset, oview_size);
1383 const off_t got_file_offset = this->got_plt_->offset();
1384 gold_assert(parameters->incremental_update()
1385 || (got_file_offset + this->got_plt_->data_size()
1386 == this->got_irelative_->offset()));
1387 const section_size_type got_size =
1388 convert_to_section_size_type(this->got_plt_->data_size()
1389 + this->got_irelative_->data_size());
1391 unsigned char* const got_view = of->get_output_view(got_file_offset,
1394 unsigned char* pov = oview;
1396 elfcpp::Elf_types<32>::Elf_Addr plt_address = this->address();
1397 elfcpp::Elf_types<32>::Elf_Addr got_address = this->got_plt_->address();
1399 this->fill_first_plt_entry(pov, got_address);
1400 pov += this->get_plt_entry_size();
1402 // The first three entries in the GOT are reserved, and are written
1403 // by Output_data_got_plt_i386::do_write.
1404 unsigned char* got_pov = got_view + 12;
1406 const int rel_size = elfcpp::Elf_sizes<32>::rel_size;
1408 unsigned int plt_offset = this->get_plt_entry_size();
1409 unsigned int plt_rel_offset = 0;
1410 unsigned int got_offset = 12;
1411 const unsigned int count = this->count_ + this->irelative_count_;
1412 for (unsigned int i = 0;
1415 pov += this->get_plt_entry_size(),
1417 plt_offset += this->get_plt_entry_size(),
1418 plt_rel_offset += rel_size,
1421 // Set and adjust the PLT entry itself.
1422 unsigned int lazy_offset = this->fill_plt_entry(pov,
1428 // Set the entry in the GOT.
1429 elfcpp::Swap<32, false>::writeval(got_pov,
1430 plt_address + plt_offset + lazy_offset);
1433 // If any STT_GNU_IFUNC symbols have PLT entries, we need to change
1434 // the GOT to point to the actual symbol value, rather than point to
1435 // the PLT entry. That will let the dynamic linker call the right
1436 // function when resolving IRELATIVE relocations.
1437 unsigned char* got_irelative_view = got_view + this->got_plt_->data_size();
1438 for (std::vector<Global_ifunc>::const_iterator p =
1439 this->global_ifuncs_.begin();
1440 p != this->global_ifuncs_.end();
1443 const Sized_symbol<32>* ssym =
1444 static_cast<const Sized_symbol<32>*>(p->sym);
1445 elfcpp::Swap<32, false>::writeval(got_irelative_view + p->got_offset,
1449 for (std::vector<Local_ifunc>::const_iterator p =
1450 this->local_ifuncs_.begin();
1451 p != this->local_ifuncs_.end();
1454 const Symbol_value<32>* psymval =
1455 p->object->local_symbol(p->local_sym_index);
1456 elfcpp::Swap<32, false>::writeval(got_irelative_view + p->got_offset,
1457 psymval->value(p->object, 0));
1460 gold_assert(static_cast<section_size_type>(pov - oview) == oview_size);
1461 gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size);
1463 of->write_output_view(offset, oview_size, oview);
1464 of->write_output_view(got_file_offset, got_size, got_view);
1467 // Create the PLT section.
1470 Target_i386::make_plt_section(Symbol_table* symtab, Layout* layout)
1472 if (this->plt_ == NULL)
1474 // Create the GOT sections first.
1475 this->got_section(symtab, layout);
1477 const bool dyn = parameters->options().output_is_position_independent();
1478 this->plt_ = this->make_data_plt(layout,
1480 this->got_irelative_,
1483 // Add unwind information if requested.
1484 if (parameters->options().ld_generated_unwind_info())
1485 this->plt_->add_eh_frame(layout);
1487 layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
1489 | elfcpp::SHF_EXECINSTR),
1490 this->plt_, ORDER_PLT, false);
1492 // Make the sh_info field of .rel.plt point to .plt.
1493 Output_section* rel_plt_os = this->plt_->rel_plt()->output_section();
1494 rel_plt_os->set_info_section(this->plt_->output_section());
1498 // Create a PLT entry for a global symbol.
1501 Target_i386::make_plt_entry(Symbol_table* symtab, Layout* layout, Symbol* gsym)
1503 if (gsym->has_plt_offset())
1505 if (this->plt_ == NULL)
1506 this->make_plt_section(symtab, layout);
1507 this->plt_->add_entry(symtab, layout, gsym);
1510 // Make a PLT entry for a local STT_GNU_IFUNC symbol.
1513 Target_i386::make_local_ifunc_plt_entry(Symbol_table* symtab, Layout* layout,
1514 Sized_relobj_file<32, false>* relobj,
1515 unsigned int local_sym_index)
1517 if (relobj->local_has_plt_offset(local_sym_index))
1519 if (this->plt_ == NULL)
1520 this->make_plt_section(symtab, layout);
1521 unsigned int plt_offset = this->plt_->add_local_ifunc_entry(symtab, layout,
1524 relobj->set_local_plt_offset(local_sym_index, plt_offset);
1527 // Return the number of entries in the PLT.
1530 Target_i386::plt_entry_count() const
1532 if (this->plt_ == NULL)
1534 return this->plt_->entry_count();
1537 // Return the offset of the first non-reserved PLT entry.
1540 Target_i386::first_plt_entry_offset() const
1542 return this->plt_->first_plt_entry_offset();
1545 // Return the size of each PLT entry.
1548 Target_i386::plt_entry_size() const
1550 return this->plt_->get_plt_entry_size();
1553 // Get the section to use for TLS_DESC relocations.
1555 Target_i386::Reloc_section*
1556 Target_i386::rel_tls_desc_section(Layout* layout) const
1558 return this->plt_section()->rel_tls_desc(layout);
1561 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
1564 Target_i386::define_tls_base_symbol(Symbol_table* symtab, Layout* layout)
1566 if (this->tls_base_symbol_defined_)
1569 Output_segment* tls_segment = layout->tls_segment();
1570 if (tls_segment != NULL)
1572 bool is_exec = parameters->options().output_is_executable();
1573 symtab->define_in_output_segment("_TLS_MODULE_BASE_", NULL,
1574 Symbol_table::PREDEFINED,
1578 elfcpp::STV_HIDDEN, 0,
1580 ? Symbol::SEGMENT_END
1581 : Symbol::SEGMENT_START),
1584 this->tls_base_symbol_defined_ = true;
1587 // Create a GOT entry for the TLS module index.
1590 Target_i386::got_mod_index_entry(Symbol_table* symtab, Layout* layout,
1591 Sized_relobj_file<32, false>* object)
1593 if (this->got_mod_index_offset_ == -1U)
1595 gold_assert(symtab != NULL && layout != NULL && object != NULL);
1596 Reloc_section* rel_dyn = this->rel_dyn_section(layout);
1597 Output_data_got<32, false>* got = this->got_section(symtab, layout);
1598 unsigned int got_offset = got->add_constant(0);
1599 rel_dyn->add_local(object, 0, elfcpp::R_386_TLS_DTPMOD32, got,
1601 got->add_constant(0);
1602 this->got_mod_index_offset_ = got_offset;
1604 return this->got_mod_index_offset_;
1607 // Optimize the TLS relocation type based on what we know about the
1608 // symbol. IS_FINAL is true if the final address of this symbol is
1609 // known at link time.
1611 tls::Tls_optimization
1612 Target_i386::optimize_tls_reloc(bool is_final, int r_type)
1614 // If we are generating a shared library, then we can't do anything
1616 if (parameters->options().shared())
1617 return tls::TLSOPT_NONE;
1621 case elfcpp::R_386_TLS_GD:
1622 case elfcpp::R_386_TLS_GOTDESC:
1623 case elfcpp::R_386_TLS_DESC_CALL:
1624 // These are General-Dynamic which permits fully general TLS
1625 // access. Since we know that we are generating an executable,
1626 // we can convert this to Initial-Exec. If we also know that
1627 // this is a local symbol, we can further switch to Local-Exec.
1629 return tls::TLSOPT_TO_LE;
1630 return tls::TLSOPT_TO_IE;
1632 case elfcpp::R_386_TLS_LDM:
1633 // This is Local-Dynamic, which refers to a local symbol in the
1634 // dynamic TLS block. Since we know that we generating an
1635 // executable, we can switch to Local-Exec.
1636 return tls::TLSOPT_TO_LE;
1638 case elfcpp::R_386_TLS_LDO_32:
1639 // Another type of Local-Dynamic relocation.
1640 return tls::TLSOPT_TO_LE;
1642 case elfcpp::R_386_TLS_IE:
1643 case elfcpp::R_386_TLS_GOTIE:
1644 case elfcpp::R_386_TLS_IE_32:
1645 // These are Initial-Exec relocs which get the thread offset
1646 // from the GOT. If we know that we are linking against the
1647 // local symbol, we can switch to Local-Exec, which links the
1648 // thread offset into the instruction.
1650 return tls::TLSOPT_TO_LE;
1651 return tls::TLSOPT_NONE;
1653 case elfcpp::R_386_TLS_LE:
1654 case elfcpp::R_386_TLS_LE_32:
1655 // When we already have Local-Exec, there is nothing further we
1657 return tls::TLSOPT_NONE;
1664 // Get the Reference_flags for a particular relocation.
1667 Target_i386::Scan::get_reference_flags(unsigned int r_type)
1671 case elfcpp::R_386_NONE:
1672 case elfcpp::R_386_GNU_VTINHERIT:
1673 case elfcpp::R_386_GNU_VTENTRY:
1674 case elfcpp::R_386_GOTPC:
1675 // No symbol reference.
1678 case elfcpp::R_386_32:
1679 case elfcpp::R_386_16:
1680 case elfcpp::R_386_8:
1681 return Symbol::ABSOLUTE_REF;
1683 case elfcpp::R_386_PC32:
1684 case elfcpp::R_386_PC16:
1685 case elfcpp::R_386_PC8:
1686 case elfcpp::R_386_GOTOFF:
1687 return Symbol::RELATIVE_REF;
1689 case elfcpp::R_386_PLT32:
1690 return Symbol::FUNCTION_CALL | Symbol::RELATIVE_REF;
1692 case elfcpp::R_386_GOT32:
1693 case elfcpp::R_386_GOT32X:
1695 return Symbol::ABSOLUTE_REF;
1697 case elfcpp::R_386_TLS_GD: // Global-dynamic
1698 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url)
1699 case elfcpp::R_386_TLS_DESC_CALL:
1700 case elfcpp::R_386_TLS_LDM: // Local-dynamic
1701 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
1702 case elfcpp::R_386_TLS_IE: // Initial-exec
1703 case elfcpp::R_386_TLS_IE_32:
1704 case elfcpp::R_386_TLS_GOTIE:
1705 case elfcpp::R_386_TLS_LE: // Local-exec
1706 case elfcpp::R_386_TLS_LE_32:
1707 return Symbol::TLS_REF;
1709 case elfcpp::R_386_COPY:
1710 case elfcpp::R_386_GLOB_DAT:
1711 case elfcpp::R_386_JUMP_SLOT:
1712 case elfcpp::R_386_RELATIVE:
1713 case elfcpp::R_386_IRELATIVE:
1714 case elfcpp::R_386_TLS_TPOFF:
1715 case elfcpp::R_386_TLS_DTPMOD32:
1716 case elfcpp::R_386_TLS_DTPOFF32:
1717 case elfcpp::R_386_TLS_TPOFF32:
1718 case elfcpp::R_386_TLS_DESC:
1719 case elfcpp::R_386_32PLT:
1720 case elfcpp::R_386_TLS_GD_32:
1721 case elfcpp::R_386_TLS_GD_PUSH:
1722 case elfcpp::R_386_TLS_GD_CALL:
1723 case elfcpp::R_386_TLS_GD_POP:
1724 case elfcpp::R_386_TLS_LDM_32:
1725 case elfcpp::R_386_TLS_LDM_PUSH:
1726 case elfcpp::R_386_TLS_LDM_CALL:
1727 case elfcpp::R_386_TLS_LDM_POP:
1728 case elfcpp::R_386_USED_BY_INTEL_200:
1730 // Not expected. We will give an error later.
1735 // Report an unsupported relocation against a local symbol.
1738 Target_i386::Scan::unsupported_reloc_local(Sized_relobj_file<32, false>* object,
1739 unsigned int r_type)
1741 gold_error(_("%s: unsupported reloc %u against local symbol"),
1742 object->name().c_str(), r_type);
1745 // Return whether we need to make a PLT entry for a relocation of a
1746 // given type against a STT_GNU_IFUNC symbol.
1749 Target_i386::Scan::reloc_needs_plt_for_ifunc(
1750 Sized_relobj_file<32, false>* object,
1751 unsigned int r_type)
1753 int flags = Scan::get_reference_flags(r_type);
1754 if (flags & Symbol::TLS_REF)
1755 gold_error(_("%s: unsupported TLS reloc %u for IFUNC symbol"),
1756 object->name().c_str(), r_type);
1760 // Scan a relocation for a local symbol.
1763 Target_i386::Scan::local(Symbol_table* symtab,
1765 Target_i386* target,
1766 Sized_relobj_file<32, false>* object,
1767 unsigned int data_shndx,
1768 Output_section* output_section,
1769 const elfcpp::Rel<32, false>& reloc,
1770 unsigned int r_type,
1771 const elfcpp::Sym<32, false>& lsym,
1777 // A local STT_GNU_IFUNC symbol may require a PLT entry.
1778 if (lsym.get_st_type() == elfcpp::STT_GNU_IFUNC
1779 && this->reloc_needs_plt_for_ifunc(object, r_type))
1781 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1782 target->make_local_ifunc_plt_entry(symtab, layout, object, r_sym);
1787 case elfcpp::R_386_NONE:
1788 case elfcpp::R_386_GNU_VTINHERIT:
1789 case elfcpp::R_386_GNU_VTENTRY:
1792 case elfcpp::R_386_32:
1793 // If building a shared library (or a position-independent
1794 // executable), we need to create a dynamic relocation for
1795 // this location. The relocation applied at link time will
1796 // apply the link-time value, so we flag the location with
1797 // an R_386_RELATIVE relocation so the dynamic loader can
1798 // relocate it easily.
1799 if (parameters->options().output_is_position_independent())
1801 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1802 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1803 rel_dyn->add_local_relative(object, r_sym, elfcpp::R_386_RELATIVE,
1804 output_section, data_shndx,
1805 reloc.get_r_offset());
1809 case elfcpp::R_386_16:
1810 case elfcpp::R_386_8:
1811 // If building a shared library (or a position-independent
1812 // executable), we need to create a dynamic relocation for
1813 // this location. Because the addend needs to remain in the
1814 // data section, we need to be careful not to apply this
1815 // relocation statically.
1816 if (parameters->options().output_is_position_independent())
1818 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1819 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1820 if (lsym.get_st_type() != elfcpp::STT_SECTION)
1821 rel_dyn->add_local(object, r_sym, r_type, output_section,
1822 data_shndx, reloc.get_r_offset());
1825 gold_assert(lsym.get_st_value() == 0);
1826 unsigned int shndx = lsym.get_st_shndx();
1828 shndx = object->adjust_sym_shndx(r_sym, shndx,
1831 object->error(_("section symbol %u has bad shndx %u"),
1834 rel_dyn->add_local_section(object, shndx,
1835 r_type, output_section,
1836 data_shndx, reloc.get_r_offset());
1841 case elfcpp::R_386_PC32:
1842 case elfcpp::R_386_PC16:
1843 case elfcpp::R_386_PC8:
1846 case elfcpp::R_386_PLT32:
1847 // Since we know this is a local symbol, we can handle this as a
1851 case elfcpp::R_386_GOTOFF:
1852 case elfcpp::R_386_GOTPC:
1853 // We need a GOT section.
1854 target->got_section(symtab, layout);
1857 case elfcpp::R_386_GOT32:
1858 case elfcpp::R_386_GOT32X:
1860 // We need GOT section.
1861 Output_data_got<32, false>* got = target->got_section(symtab, layout);
1863 // If the relocation symbol isn't IFUNC,
1864 // and is local, then we will convert
1865 // mov foo@GOT(%reg), %reg
1867 // lea foo@GOTOFF(%reg), %reg
1868 // in Relocate::relocate.
1869 if (reloc.get_r_offset() >= 2
1870 && lsym.get_st_type() != elfcpp::STT_GNU_IFUNC)
1872 section_size_type stype;
1873 const unsigned char* view = object->section_contents(data_shndx,
1875 if (view[reloc.get_r_offset() - 2] == 0x8b)
1879 // Otherwise, the symbol requires a GOT entry.
1880 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1882 // For a STT_GNU_IFUNC symbol we want the PLT offset. That
1883 // lets function pointers compare correctly with shared
1884 // libraries. Otherwise we would need an IRELATIVE reloc.
1886 if (lsym.get_st_type() == elfcpp::STT_GNU_IFUNC)
1887 is_new = got->add_local_plt(object, r_sym, GOT_TYPE_STANDARD);
1889 is_new = got->add_local(object, r_sym, GOT_TYPE_STANDARD);
1892 // If we are generating a shared object, we need to add a
1893 // dynamic RELATIVE relocation for this symbol's GOT entry.
1894 if (parameters->options().output_is_position_independent())
1896 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1897 unsigned int got_offset =
1898 object->local_got_offset(r_sym, GOT_TYPE_STANDARD);
1899 rel_dyn->add_local_relative(object, r_sym,
1900 elfcpp::R_386_RELATIVE,
1907 // These are relocations which should only be seen by the
1908 // dynamic linker, and should never be seen here.
1909 case elfcpp::R_386_COPY:
1910 case elfcpp::R_386_GLOB_DAT:
1911 case elfcpp::R_386_JUMP_SLOT:
1912 case elfcpp::R_386_RELATIVE:
1913 case elfcpp::R_386_IRELATIVE:
1914 case elfcpp::R_386_TLS_TPOFF:
1915 case elfcpp::R_386_TLS_DTPMOD32:
1916 case elfcpp::R_386_TLS_DTPOFF32:
1917 case elfcpp::R_386_TLS_TPOFF32:
1918 case elfcpp::R_386_TLS_DESC:
1919 gold_error(_("%s: unexpected reloc %u in object file"),
1920 object->name().c_str(), r_type);
1923 // These are initial TLS relocs, which are expected when
1925 case elfcpp::R_386_TLS_GD: // Global-dynamic
1926 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url)
1927 case elfcpp::R_386_TLS_DESC_CALL:
1928 case elfcpp::R_386_TLS_LDM: // Local-dynamic
1929 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
1930 case elfcpp::R_386_TLS_IE: // Initial-exec
1931 case elfcpp::R_386_TLS_IE_32:
1932 case elfcpp::R_386_TLS_GOTIE:
1933 case elfcpp::R_386_TLS_LE: // Local-exec
1934 case elfcpp::R_386_TLS_LE_32:
1936 bool output_is_shared = parameters->options().shared();
1937 const tls::Tls_optimization optimized_type
1938 = Target_i386::optimize_tls_reloc(!output_is_shared, r_type);
1941 case elfcpp::R_386_TLS_GD: // Global-dynamic
1942 if (optimized_type == tls::TLSOPT_NONE)
1944 // Create a pair of GOT entries for the module index and
1945 // dtv-relative offset.
1946 Output_data_got<32, false>* got
1947 = target->got_section(symtab, layout);
1948 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1949 unsigned int shndx = lsym.get_st_shndx();
1951 shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
1953 object->error(_("local symbol %u has bad shndx %u"),
1956 got->add_local_pair_with_rel(object, r_sym, shndx,
1958 target->rel_dyn_section(layout),
1959 elfcpp::R_386_TLS_DTPMOD32);
1961 else if (optimized_type != tls::TLSOPT_TO_LE)
1962 unsupported_reloc_local(object, r_type);
1965 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva)
1966 target->define_tls_base_symbol(symtab, layout);
1967 if (optimized_type == tls::TLSOPT_NONE)
1969 // Create a double GOT entry with an R_386_TLS_DESC
1970 // reloc. The R_386_TLS_DESC reloc is resolved
1971 // lazily, so the GOT entry needs to be in an area in
1972 // .got.plt, not .got. Call got_section to make sure
1973 // the section has been created.
1974 target->got_section(symtab, layout);
1975 Output_data_got<32, false>* got = target->got_tlsdesc_section();
1976 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1977 if (!object->local_has_got_offset(r_sym, GOT_TYPE_TLS_DESC))
1979 unsigned int got_offset = got->add_constant(0);
1980 // The local symbol value is stored in the second
1982 got->add_local(object, r_sym, GOT_TYPE_TLS_DESC);
1983 // That set the GOT offset of the local symbol to
1984 // point to the second entry, but we want it to
1985 // point to the first.
1986 object->set_local_got_offset(r_sym, GOT_TYPE_TLS_DESC,
1988 Reloc_section* rt = target->rel_tls_desc_section(layout);
1989 rt->add_absolute(elfcpp::R_386_TLS_DESC, got, got_offset);
1992 else if (optimized_type != tls::TLSOPT_TO_LE)
1993 unsupported_reloc_local(object, r_type);
1996 case elfcpp::R_386_TLS_DESC_CALL:
1999 case elfcpp::R_386_TLS_LDM: // Local-dynamic
2000 if (optimized_type == tls::TLSOPT_NONE)
2002 // Create a GOT entry for the module index.
2003 target->got_mod_index_entry(symtab, layout, object);
2005 else if (optimized_type != tls::TLSOPT_TO_LE)
2006 unsupported_reloc_local(object, r_type);
2009 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
2012 case elfcpp::R_386_TLS_IE: // Initial-exec
2013 case elfcpp::R_386_TLS_IE_32:
2014 case elfcpp::R_386_TLS_GOTIE:
2015 layout->set_has_static_tls();
2016 if (optimized_type == tls::TLSOPT_NONE)
2018 // For the R_386_TLS_IE relocation, we need to create a
2019 // dynamic relocation when building a shared library.
2020 if (r_type == elfcpp::R_386_TLS_IE
2021 && parameters->options().shared())
2023 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
2025 = elfcpp::elf_r_sym<32>(reloc.get_r_info());
2026 rel_dyn->add_local_relative(object, r_sym,
2027 elfcpp::R_386_RELATIVE,
2028 output_section, data_shndx,
2029 reloc.get_r_offset());
2031 // Create a GOT entry for the tp-relative offset.
2032 Output_data_got<32, false>* got
2033 = target->got_section(symtab, layout);
2034 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
2035 unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_IE_32
2036 ? elfcpp::R_386_TLS_TPOFF32
2037 : elfcpp::R_386_TLS_TPOFF);
2038 unsigned int got_type = (r_type == elfcpp::R_386_TLS_IE_32
2039 ? GOT_TYPE_TLS_OFFSET
2040 : GOT_TYPE_TLS_NOFFSET);
2041 got->add_local_with_rel(object, r_sym, got_type,
2042 target->rel_dyn_section(layout),
2045 else if (optimized_type != tls::TLSOPT_TO_LE)
2046 unsupported_reloc_local(object, r_type);
2049 case elfcpp::R_386_TLS_LE: // Local-exec
2050 case elfcpp::R_386_TLS_LE_32:
2051 layout->set_has_static_tls();
2052 if (output_is_shared)
2054 // We need to create a dynamic relocation.
2055 gold_assert(lsym.get_st_type() != elfcpp::STT_SECTION);
2056 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
2057 unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_LE_32
2058 ? elfcpp::R_386_TLS_TPOFF32
2059 : elfcpp::R_386_TLS_TPOFF);
2060 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
2061 rel_dyn->add_local(object, r_sym, dyn_r_type, output_section,
2062 data_shndx, reloc.get_r_offset());
2072 case elfcpp::R_386_32PLT:
2073 case elfcpp::R_386_TLS_GD_32:
2074 case elfcpp::R_386_TLS_GD_PUSH:
2075 case elfcpp::R_386_TLS_GD_CALL:
2076 case elfcpp::R_386_TLS_GD_POP:
2077 case elfcpp::R_386_TLS_LDM_32:
2078 case elfcpp::R_386_TLS_LDM_PUSH:
2079 case elfcpp::R_386_TLS_LDM_CALL:
2080 case elfcpp::R_386_TLS_LDM_POP:
2081 case elfcpp::R_386_USED_BY_INTEL_200:
2083 unsupported_reloc_local(object, r_type);
2088 // Report an unsupported relocation against a global symbol.
2091 Target_i386::Scan::unsupported_reloc_global(
2092 Sized_relobj_file<32, false>* object,
2093 unsigned int r_type,
2096 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
2097 object->name().c_str(), r_type, gsym->demangled_name().c_str());
2101 Target_i386::Scan::possible_function_pointer_reloc(unsigned int r_type)
2105 case elfcpp::R_386_32:
2106 case elfcpp::R_386_16:
2107 case elfcpp::R_386_8:
2108 case elfcpp::R_386_GOTOFF:
2109 case elfcpp::R_386_GOT32:
2110 case elfcpp::R_386_GOT32X:
2121 Target_i386::Scan::local_reloc_may_be_function_pointer(
2125 Sized_relobj_file<32, false>* ,
2128 const elfcpp::Rel<32, false>& ,
2129 unsigned int r_type,
2130 const elfcpp::Sym<32, false>&)
2132 return possible_function_pointer_reloc(r_type);
2136 Target_i386::Scan::global_reloc_may_be_function_pointer(
2140 Sized_relobj_file<32, false>* ,
2143 const elfcpp::Rel<32, false>& ,
2144 unsigned int r_type,
2147 return possible_function_pointer_reloc(r_type);
2150 // Scan a relocation for a global symbol.
2153 Target_i386::Scan::global(Symbol_table* symtab,
2155 Target_i386* target,
2156 Sized_relobj_file<32, false>* object,
2157 unsigned int data_shndx,
2158 Output_section* output_section,
2159 const elfcpp::Rel<32, false>& reloc,
2160 unsigned int r_type,
2163 // A STT_GNU_IFUNC symbol may require a PLT entry.
2164 if (gsym->type() == elfcpp::STT_GNU_IFUNC
2165 && this->reloc_needs_plt_for_ifunc(object, r_type))
2166 target->make_plt_entry(symtab, layout, gsym);
2170 case elfcpp::R_386_NONE:
2171 case elfcpp::R_386_GNU_VTINHERIT:
2172 case elfcpp::R_386_GNU_VTENTRY:
2175 case elfcpp::R_386_32:
2176 case elfcpp::R_386_16:
2177 case elfcpp::R_386_8:
2179 // Make a PLT entry if necessary.
2180 if (gsym->needs_plt_entry())
2182 target->make_plt_entry(symtab, layout, gsym);
2183 // Since this is not a PC-relative relocation, we may be
2184 // taking the address of a function. In that case we need to
2185 // set the entry in the dynamic symbol table to the address of
2187 if (gsym->is_from_dynobj() && !parameters->options().shared())
2188 gsym->set_needs_dynsym_value();
2190 // Make a dynamic relocation if necessary.
2191 if (gsym->needs_dynamic_reloc(Scan::get_reference_flags(r_type)))
2193 if (!parameters->options().output_is_position_independent()
2194 && gsym->may_need_copy_reloc())
2196 target->copy_reloc(symtab, layout, object,
2197 data_shndx, output_section, gsym, reloc);
2199 else if (r_type == elfcpp::R_386_32
2200 && gsym->type() == elfcpp::STT_GNU_IFUNC
2201 && gsym->can_use_relative_reloc(false)
2202 && !gsym->is_from_dynobj()
2203 && !gsym->is_undefined()
2204 && !gsym->is_preemptible())
2206 // Use an IRELATIVE reloc for a locally defined
2207 // STT_GNU_IFUNC symbol. This makes a function
2208 // address in a PIE executable match the address in a
2209 // shared library that it links against.
2210 Reloc_section* rel_dyn = target->rel_irelative_section(layout);
2211 rel_dyn->add_symbolless_global_addend(gsym,
2212 elfcpp::R_386_IRELATIVE,
2215 reloc.get_r_offset());
2217 else if (r_type == elfcpp::R_386_32
2218 && gsym->can_use_relative_reloc(false))
2220 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
2221 rel_dyn->add_global_relative(gsym, elfcpp::R_386_RELATIVE,
2222 output_section, object,
2223 data_shndx, reloc.get_r_offset());
2227 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
2228 rel_dyn->add_global(gsym, r_type, output_section, object,
2229 data_shndx, reloc.get_r_offset());
2235 case elfcpp::R_386_PC32:
2236 case elfcpp::R_386_PC16:
2237 case elfcpp::R_386_PC8:
2239 // Make a PLT entry if necessary.
2240 if (gsym->needs_plt_entry())
2242 // These relocations are used for function calls only in
2243 // non-PIC code. For a 32-bit relocation in a shared library,
2244 // we'll need a text relocation anyway, so we can skip the
2245 // PLT entry and let the dynamic linker bind the call directly
2246 // to the target. For smaller relocations, we should use a
2247 // PLT entry to ensure that the call can reach.
2248 if (!parameters->options().shared()
2249 || r_type != elfcpp::R_386_PC32)
2250 target->make_plt_entry(symtab, layout, gsym);
2252 // Make a dynamic relocation if necessary.
2253 if (gsym->needs_dynamic_reloc(Scan::get_reference_flags(r_type)))
2255 if (parameters->options().output_is_executable()
2256 && gsym->may_need_copy_reloc())
2258 target->copy_reloc(symtab, layout, object,
2259 data_shndx, output_section, gsym, reloc);
2263 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
2264 rel_dyn->add_global(gsym, r_type, output_section, object,
2265 data_shndx, reloc.get_r_offset());
2271 case elfcpp::R_386_GOT32:
2272 case elfcpp::R_386_GOT32X:
2274 // The symbol requires a GOT section.
2275 Output_data_got<32, false>* got = target->got_section(symtab, layout);
2277 // If we convert this from
2278 // mov foo@GOT(%reg), %reg
2280 // lea foo@GOTOFF(%reg), %reg
2281 // in Relocate::relocate, then there is nothing to do here.
2282 if (reloc.get_r_offset() >= 2
2283 && Target_i386::can_convert_mov_to_lea(gsym))
2285 section_size_type stype;
2286 const unsigned char* view = object->section_contents(data_shndx,
2288 if (view[reloc.get_r_offset() - 2] == 0x8b)
2292 if (gsym->final_value_is_known())
2294 // For a STT_GNU_IFUNC symbol we want the PLT address.
2295 if (gsym->type() == elfcpp::STT_GNU_IFUNC)
2296 got->add_global_plt(gsym, GOT_TYPE_STANDARD);
2298 got->add_global(gsym, GOT_TYPE_STANDARD);
2302 // If this symbol is not fully resolved, we need to add a
2303 // GOT entry with a dynamic relocation.
2304 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
2306 // Use a GLOB_DAT rather than a RELATIVE reloc if:
2308 // 1) The symbol may be defined in some other module.
2310 // 2) We are building a shared library and this is a
2311 // protected symbol; using GLOB_DAT means that the dynamic
2312 // linker can use the address of the PLT in the main
2313 // executable when appropriate so that function address
2314 // comparisons work.
2316 // 3) This is a STT_GNU_IFUNC symbol in position dependent
2317 // code, again so that function address comparisons work.
2318 if (gsym->is_from_dynobj()
2319 || gsym->is_undefined()
2320 || gsym->is_preemptible()
2321 || (gsym->visibility() == elfcpp::STV_PROTECTED
2322 && parameters->options().shared())
2323 || (gsym->type() == elfcpp::STT_GNU_IFUNC
2324 && parameters->options().output_is_position_independent()))
2325 got->add_global_with_rel(gsym, GOT_TYPE_STANDARD,
2326 rel_dyn, elfcpp::R_386_GLOB_DAT);
2329 // For a STT_GNU_IFUNC symbol we want to write the PLT
2330 // offset into the GOT, so that function pointer
2331 // comparisons work correctly.
2333 if (gsym->type() != elfcpp::STT_GNU_IFUNC)
2334 is_new = got->add_global(gsym, GOT_TYPE_STANDARD);
2337 is_new = got->add_global_plt(gsym, GOT_TYPE_STANDARD);
2338 // Tell the dynamic linker to use the PLT address
2339 // when resolving relocations.
2340 if (gsym->is_from_dynobj()
2341 && !parameters->options().shared())
2342 gsym->set_needs_dynsym_value();
2346 unsigned int got_off = gsym->got_offset(GOT_TYPE_STANDARD);
2347 rel_dyn->add_global_relative(gsym, elfcpp::R_386_RELATIVE,
2355 case elfcpp::R_386_PLT32:
2356 // If the symbol is fully resolved, this is just a PC32 reloc.
2357 // Otherwise we need a PLT entry.
2358 if (gsym->final_value_is_known())
2360 // If building a shared library, we can also skip the PLT entry
2361 // if the symbol is defined in the output file and is protected
2363 if (gsym->is_defined()
2364 && !gsym->is_from_dynobj()
2365 && !gsym->is_preemptible())
2367 target->make_plt_entry(symtab, layout, gsym);
2370 case elfcpp::R_386_GOTOFF:
2371 case elfcpp::R_386_GOTPC:
2372 // We need a GOT section.
2373 target->got_section(symtab, layout);
2376 // These are relocations which should only be seen by the
2377 // dynamic linker, and should never be seen here.
2378 case elfcpp::R_386_COPY:
2379 case elfcpp::R_386_GLOB_DAT:
2380 case elfcpp::R_386_JUMP_SLOT:
2381 case elfcpp::R_386_RELATIVE:
2382 case elfcpp::R_386_IRELATIVE:
2383 case elfcpp::R_386_TLS_TPOFF:
2384 case elfcpp::R_386_TLS_DTPMOD32:
2385 case elfcpp::R_386_TLS_DTPOFF32:
2386 case elfcpp::R_386_TLS_TPOFF32:
2387 case elfcpp::R_386_TLS_DESC:
2388 gold_error(_("%s: unexpected reloc %u in object file"),
2389 object->name().c_str(), r_type);
2392 // These are initial tls relocs, which are expected when
2394 case elfcpp::R_386_TLS_GD: // Global-dynamic
2395 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url)
2396 case elfcpp::R_386_TLS_DESC_CALL:
2397 case elfcpp::R_386_TLS_LDM: // Local-dynamic
2398 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
2399 case elfcpp::R_386_TLS_IE: // Initial-exec
2400 case elfcpp::R_386_TLS_IE_32:
2401 case elfcpp::R_386_TLS_GOTIE:
2402 case elfcpp::R_386_TLS_LE: // Local-exec
2403 case elfcpp::R_386_TLS_LE_32:
2405 const bool is_final = gsym->final_value_is_known();
2406 const tls::Tls_optimization optimized_type
2407 = Target_i386::optimize_tls_reloc(is_final, r_type);
2410 case elfcpp::R_386_TLS_GD: // Global-dynamic
2411 if (optimized_type == tls::TLSOPT_NONE)
2413 // Create a pair of GOT entries for the module index and
2414 // dtv-relative offset.
2415 Output_data_got<32, false>* got
2416 = target->got_section(symtab, layout);
2417 got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_PAIR,
2418 target->rel_dyn_section(layout),
2419 elfcpp::R_386_TLS_DTPMOD32,
2420 elfcpp::R_386_TLS_DTPOFF32);
2422 else if (optimized_type == tls::TLSOPT_TO_IE)
2424 // Create a GOT entry for the tp-relative offset.
2425 Output_data_got<32, false>* got
2426 = target->got_section(symtab, layout);
2427 got->add_global_with_rel(gsym, GOT_TYPE_TLS_NOFFSET,
2428 target->rel_dyn_section(layout),
2429 elfcpp::R_386_TLS_TPOFF);
2431 else if (optimized_type != tls::TLSOPT_TO_LE)
2432 unsupported_reloc_global(object, r_type, gsym);
2435 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (~oliva url)
2436 target->define_tls_base_symbol(symtab, layout);
2437 if (optimized_type == tls::TLSOPT_NONE)
2439 // Create a double GOT entry with an R_386_TLS_DESC
2440 // reloc. The R_386_TLS_DESC reloc is resolved
2441 // lazily, so the GOT entry needs to be in an area in
2442 // .got.plt, not .got. Call got_section to make sure
2443 // the section has been created.
2444 target->got_section(symtab, layout);
2445 Output_data_got<32, false>* got = target->got_tlsdesc_section();
2446 Reloc_section* rt = target->rel_tls_desc_section(layout);
2447 got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_DESC, rt,
2448 elfcpp::R_386_TLS_DESC, 0);
2450 else if (optimized_type == tls::TLSOPT_TO_IE)
2452 // Create a GOT entry for the tp-relative offset.
2453 Output_data_got<32, false>* got
2454 = target->got_section(symtab, layout);
2455 got->add_global_with_rel(gsym, GOT_TYPE_TLS_NOFFSET,
2456 target->rel_dyn_section(layout),
2457 elfcpp::R_386_TLS_TPOFF);
2459 else if (optimized_type != tls::TLSOPT_TO_LE)
2460 unsupported_reloc_global(object, r_type, gsym);
2463 case elfcpp::R_386_TLS_DESC_CALL:
2466 case elfcpp::R_386_TLS_LDM: // Local-dynamic
2467 if (optimized_type == tls::TLSOPT_NONE)
2469 // Create a GOT entry for the module index.
2470 target->got_mod_index_entry(symtab, layout, object);
2472 else if (optimized_type != tls::TLSOPT_TO_LE)
2473 unsupported_reloc_global(object, r_type, gsym);
2476 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
2479 case elfcpp::R_386_TLS_IE: // Initial-exec
2480 case elfcpp::R_386_TLS_IE_32:
2481 case elfcpp::R_386_TLS_GOTIE:
2482 layout->set_has_static_tls();
2483 if (optimized_type == tls::TLSOPT_NONE)
2485 // For the R_386_TLS_IE relocation, we need to create a
2486 // dynamic relocation when building a shared library.
2487 if (r_type == elfcpp::R_386_TLS_IE
2488 && parameters->options().shared())
2490 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
2491 rel_dyn->add_global_relative(gsym, elfcpp::R_386_RELATIVE,
2492 output_section, object,
2494 reloc.get_r_offset());
2496 // Create a GOT entry for the tp-relative offset.
2497 Output_data_got<32, false>* got
2498 = target->got_section(symtab, layout);
2499 unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_IE_32
2500 ? elfcpp::R_386_TLS_TPOFF32
2501 : elfcpp::R_386_TLS_TPOFF);
2502 unsigned int got_type = (r_type == elfcpp::R_386_TLS_IE_32
2503 ? GOT_TYPE_TLS_OFFSET
2504 : GOT_TYPE_TLS_NOFFSET);
2505 got->add_global_with_rel(gsym, got_type,
2506 target->rel_dyn_section(layout),
2509 else if (optimized_type != tls::TLSOPT_TO_LE)
2510 unsupported_reloc_global(object, r_type, gsym);
2513 case elfcpp::R_386_TLS_LE: // Local-exec
2514 case elfcpp::R_386_TLS_LE_32:
2515 layout->set_has_static_tls();
2516 if (parameters->options().shared())
2518 // We need to create a dynamic relocation.
2519 unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_LE_32
2520 ? elfcpp::R_386_TLS_TPOFF32
2521 : elfcpp::R_386_TLS_TPOFF);
2522 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
2523 rel_dyn->add_global(gsym, dyn_r_type, output_section, object,
2524 data_shndx, reloc.get_r_offset());
2534 case elfcpp::R_386_32PLT:
2535 case elfcpp::R_386_TLS_GD_32:
2536 case elfcpp::R_386_TLS_GD_PUSH:
2537 case elfcpp::R_386_TLS_GD_CALL:
2538 case elfcpp::R_386_TLS_GD_POP:
2539 case elfcpp::R_386_TLS_LDM_32:
2540 case elfcpp::R_386_TLS_LDM_PUSH:
2541 case elfcpp::R_386_TLS_LDM_CALL:
2542 case elfcpp::R_386_TLS_LDM_POP:
2543 case elfcpp::R_386_USED_BY_INTEL_200:
2545 unsupported_reloc_global(object, r_type, gsym);
2550 // Process relocations for gc.
2553 Target_i386::gc_process_relocs(Symbol_table* symtab,
2555 Sized_relobj_file<32, false>* object,
2556 unsigned int data_shndx,
2558 const unsigned char* prelocs,
2560 Output_section* output_section,
2561 bool needs_special_offset_handling,
2562 size_t local_symbol_count,
2563 const unsigned char* plocal_symbols)
2565 gold::gc_process_relocs<32, false, Target_i386, elfcpp::SHT_REL,
2567 Target_i386::Relocatable_size_for_reloc>(
2576 needs_special_offset_handling,
2581 // Scan relocations for a section.
2584 Target_i386::scan_relocs(Symbol_table* symtab,
2586 Sized_relobj_file<32, false>* object,
2587 unsigned int data_shndx,
2588 unsigned int sh_type,
2589 const unsigned char* prelocs,
2591 Output_section* output_section,
2592 bool needs_special_offset_handling,
2593 size_t local_symbol_count,
2594 const unsigned char* plocal_symbols)
2596 if (sh_type == elfcpp::SHT_RELA)
2598 gold_error(_("%s: unsupported RELA reloc section"),
2599 object->name().c_str());
2603 gold::scan_relocs<32, false, Target_i386, elfcpp::SHT_REL,
2613 needs_special_offset_handling,
2618 // Finalize the sections.
2621 Target_i386::do_finalize_sections(
2623 const Input_objects*,
2624 Symbol_table* symtab)
2626 const Reloc_section* rel_plt = (this->plt_ == NULL
2628 : this->plt_->rel_plt());
2629 layout->add_target_dynamic_tags(true, this->got_plt_, rel_plt,
2630 this->rel_dyn_, true, false);
2632 // Emit any relocs we saved in an attempt to avoid generating COPY
2634 if (this->copy_relocs_.any_saved_relocs())
2635 this->copy_relocs_.emit(this->rel_dyn_section(layout));
2637 // Set the size of the _GLOBAL_OFFSET_TABLE_ symbol to the size of
2638 // the .got.plt section.
2639 Symbol* sym = this->global_offset_table_;
2642 uint32_t data_size = this->got_plt_->current_data_size();
2643 symtab->get_sized_symbol<32>(sym)->set_symsize(data_size);
2646 if (parameters->doing_static_link()
2647 && (this->plt_ == NULL || !this->plt_->has_irelative_section()))
2649 // If linking statically, make sure that the __rel_iplt symbols
2650 // were defined if necessary, even if we didn't create a PLT.
2651 static const Define_symbol_in_segment syms[] =
2654 "__rel_iplt_start", // name
2655 elfcpp::PT_LOAD, // segment_type
2656 elfcpp::PF_W, // segment_flags_set
2657 elfcpp::PF(0), // segment_flags_clear
2660 elfcpp::STT_NOTYPE, // type
2661 elfcpp::STB_GLOBAL, // binding
2662 elfcpp::STV_HIDDEN, // visibility
2664 Symbol::SEGMENT_START, // offset_from_base
2668 "__rel_iplt_end", // name
2669 elfcpp::PT_LOAD, // segment_type
2670 elfcpp::PF_W, // segment_flags_set
2671 elfcpp::PF(0), // segment_flags_clear
2674 elfcpp::STT_NOTYPE, // type
2675 elfcpp::STB_GLOBAL, // binding
2676 elfcpp::STV_HIDDEN, // visibility
2678 Symbol::SEGMENT_START, // offset_from_base
2683 symtab->define_symbols(layout, 2, syms,
2684 layout->script_options()->saw_sections_clause());
2688 // Return whether a direct absolute static relocation needs to be applied.
2689 // In cases where Scan::local() or Scan::global() has created
2690 // a dynamic relocation other than R_386_RELATIVE, the addend
2691 // of the relocation is carried in the data, and we must not
2692 // apply the static relocation.
2695 Target_i386::Relocate::should_apply_static_reloc(const Sized_symbol<32>* gsym,
2696 unsigned int r_type,
2698 Output_section* output_section)
2700 // If the output section is not allocated, then we didn't call
2701 // scan_relocs, we didn't create a dynamic reloc, and we must apply
2703 if ((output_section->flags() & elfcpp::SHF_ALLOC) == 0)
2706 int ref_flags = Scan::get_reference_flags(r_type);
2708 // For local symbols, we will have created a non-RELATIVE dynamic
2709 // relocation only if (a) the output is position independent,
2710 // (b) the relocation is absolute (not pc- or segment-relative), and
2711 // (c) the relocation is not 32 bits wide.
2713 return !(parameters->options().output_is_position_independent()
2714 && (ref_flags & Symbol::ABSOLUTE_REF)
2717 // For global symbols, we use the same helper routines used in the
2718 // scan pass. If we did not create a dynamic relocation, or if we
2719 // created a RELATIVE dynamic relocation, we should apply the static
2721 bool has_dyn = gsym->needs_dynamic_reloc(ref_flags);
2722 bool is_rel = (ref_flags & Symbol::ABSOLUTE_REF)
2723 && gsym->can_use_relative_reloc(ref_flags
2724 & Symbol::FUNCTION_CALL);
2725 return !has_dyn || is_rel;
2728 // Perform a relocation.
2731 Target_i386::Relocate::relocate(const Relocate_info<32, false>* relinfo,
2732 Target_i386* target,
2733 Output_section* output_section,
2735 const elfcpp::Rel<32, false>& rel,
2736 unsigned int r_type,
2737 const Sized_symbol<32>* gsym,
2738 const Symbol_value<32>* psymval,
2739 unsigned char* view,
2740 elfcpp::Elf_types<32>::Elf_Addr address,
2741 section_size_type view_size)
2743 if (this->skip_call_tls_get_addr_)
2745 if ((r_type != elfcpp::R_386_PLT32
2746 && r_type != elfcpp::R_386_PC32)
2748 || strcmp(gsym->name(), "___tls_get_addr") != 0)
2749 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
2750 _("missing expected TLS relocation"));
2753 this->skip_call_tls_get_addr_ = false;
2761 const Sized_relobj_file<32, false>* object = relinfo->object;
2763 // Pick the value to use for symbols defined in shared objects.
2764 Symbol_value<32> symval;
2766 && gsym->type() == elfcpp::STT_GNU_IFUNC
2767 && r_type == elfcpp::R_386_32
2768 && gsym->needs_dynamic_reloc(Scan::get_reference_flags(r_type))
2769 && gsym->can_use_relative_reloc(false)
2770 && !gsym->is_from_dynobj()
2771 && !gsym->is_undefined()
2772 && !gsym->is_preemptible())
2774 // In this case we are generating a R_386_IRELATIVE reloc. We
2775 // want to use the real value of the symbol, not the PLT offset.
2777 else if (gsym != NULL
2778 && gsym->use_plt_offset(Scan::get_reference_flags(r_type)))
2780 symval.set_output_value(target->plt_address_for_global(gsym));
2783 else if (gsym == NULL && psymval->is_ifunc_symbol())
2785 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
2786 if (object->local_has_plt_offset(r_sym))
2788 symval.set_output_value(target->plt_address_for_local(object, r_sym));
2795 case elfcpp::R_386_NONE:
2796 case elfcpp::R_386_GNU_VTINHERIT:
2797 case elfcpp::R_386_GNU_VTENTRY:
2800 case elfcpp::R_386_32:
2801 if (should_apply_static_reloc(gsym, r_type, true, output_section))
2802 Relocate_functions<32, false>::rel32(view, object, psymval);
2805 case elfcpp::R_386_PC32:
2806 if (should_apply_static_reloc(gsym, r_type, true, output_section))
2807 Relocate_functions<32, false>::pcrel32(view, object, psymval, address);
2810 case elfcpp::R_386_16:
2811 if (should_apply_static_reloc(gsym, r_type, false, output_section))
2812 Relocate_functions<32, false>::rel16(view, object, psymval);
2815 case elfcpp::R_386_PC16:
2816 if (should_apply_static_reloc(gsym, r_type, false, output_section))
2817 Relocate_functions<32, false>::pcrel16(view, object, psymval, address);
2820 case elfcpp::R_386_8:
2821 if (should_apply_static_reloc(gsym, r_type, false, output_section))
2822 Relocate_functions<32, false>::rel8(view, object, psymval);
2825 case elfcpp::R_386_PC8:
2826 if (should_apply_static_reloc(gsym, r_type, false, output_section))
2827 Relocate_functions<32, false>::pcrel8(view, object, psymval, address);
2830 case elfcpp::R_386_PLT32:
2831 gold_assert(gsym == NULL
2832 || gsym->has_plt_offset()
2833 || gsym->final_value_is_known()
2834 || (gsym->is_defined()
2835 && !gsym->is_from_dynobj()
2836 && !gsym->is_preemptible()));
2837 Relocate_functions<32, false>::pcrel32(view, object, psymval, address);
2840 case elfcpp::R_386_GOT32:
2841 case elfcpp::R_386_GOT32X:
2843 // mov foo@GOT(%reg), %reg
2845 // lea foo@GOTOFF(%reg), %reg
2847 if (rel.get_r_offset() >= 2
2849 && ((gsym == NULL && !psymval->is_ifunc_symbol())
2851 && Target_i386::can_convert_mov_to_lea(gsym))))
2854 elfcpp::Elf_types<32>::Elf_Addr value;
2855 value = (psymval->value(object, 0)
2856 - target->got_plt_section()->address());
2857 Relocate_functions<32, false>::rel32(view, value);
2861 // The GOT pointer points to the end of the GOT section.
2862 // We need to subtract the size of the GOT section to get
2863 // the actual offset to use in the relocation.
2864 unsigned int got_offset = 0;
2867 gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
2868 got_offset = (gsym->got_offset(GOT_TYPE_STANDARD)
2869 - target->got_size());
2873 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
2874 gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD));
2875 got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD)
2876 - target->got_size());
2878 Relocate_functions<32, false>::rel32(view, got_offset);
2882 case elfcpp::R_386_GOTOFF:
2884 elfcpp::Elf_types<32>::Elf_Addr value;
2885 value = (psymval->value(object, 0)
2886 - target->got_plt_section()->address());
2887 Relocate_functions<32, false>::rel32(view, value);
2891 case elfcpp::R_386_GOTPC:
2893 elfcpp::Elf_types<32>::Elf_Addr value;
2894 value = target->got_plt_section()->address();
2895 Relocate_functions<32, false>::pcrel32(view, value, address);
2899 case elfcpp::R_386_COPY:
2900 case elfcpp::R_386_GLOB_DAT:
2901 case elfcpp::R_386_JUMP_SLOT:
2902 case elfcpp::R_386_RELATIVE:
2903 case elfcpp::R_386_IRELATIVE:
2904 // These are outstanding tls relocs, which are unexpected when
2906 case elfcpp::R_386_TLS_TPOFF:
2907 case elfcpp::R_386_TLS_DTPMOD32:
2908 case elfcpp::R_386_TLS_DTPOFF32:
2909 case elfcpp::R_386_TLS_TPOFF32:
2910 case elfcpp::R_386_TLS_DESC:
2911 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
2912 _("unexpected reloc %u in object file"),
2916 // These are initial tls relocs, which are expected when
2918 case elfcpp::R_386_TLS_GD: // Global-dynamic
2919 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url)
2920 case elfcpp::R_386_TLS_DESC_CALL:
2921 case elfcpp::R_386_TLS_LDM: // Local-dynamic
2922 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
2923 case elfcpp::R_386_TLS_IE: // Initial-exec
2924 case elfcpp::R_386_TLS_IE_32:
2925 case elfcpp::R_386_TLS_GOTIE:
2926 case elfcpp::R_386_TLS_LE: // Local-exec
2927 case elfcpp::R_386_TLS_LE_32:
2928 this->relocate_tls(relinfo, target, relnum, rel, r_type, gsym, psymval,
2929 view, address, view_size);
2932 case elfcpp::R_386_32PLT:
2933 case elfcpp::R_386_TLS_GD_32:
2934 case elfcpp::R_386_TLS_GD_PUSH:
2935 case elfcpp::R_386_TLS_GD_CALL:
2936 case elfcpp::R_386_TLS_GD_POP:
2937 case elfcpp::R_386_TLS_LDM_32:
2938 case elfcpp::R_386_TLS_LDM_PUSH:
2939 case elfcpp::R_386_TLS_LDM_CALL:
2940 case elfcpp::R_386_TLS_LDM_POP:
2941 case elfcpp::R_386_USED_BY_INTEL_200:
2943 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
2944 _("unsupported reloc %u"),
2952 // Perform a TLS relocation.
2955 Target_i386::Relocate::relocate_tls(const Relocate_info<32, false>* relinfo,
2956 Target_i386* target,
2958 const elfcpp::Rel<32, false>& rel,
2959 unsigned int r_type,
2960 const Sized_symbol<32>* gsym,
2961 const Symbol_value<32>* psymval,
2962 unsigned char* view,
2963 elfcpp::Elf_types<32>::Elf_Addr,
2964 section_size_type view_size)
2966 Output_segment* tls_segment = relinfo->layout->tls_segment();
2968 const Sized_relobj_file<32, false>* object = relinfo->object;
2970 elfcpp::Elf_types<32>::Elf_Addr value = psymval->value(object, 0);
2972 const bool is_final = (gsym == NULL
2973 ? !parameters->options().shared()
2974 : gsym->final_value_is_known());
2975 const tls::Tls_optimization optimized_type
2976 = Target_i386::optimize_tls_reloc(is_final, r_type);
2979 case elfcpp::R_386_TLS_GD: // Global-dynamic
2980 if (optimized_type == tls::TLSOPT_TO_LE)
2982 if (tls_segment == NULL)
2984 gold_assert(parameters->errors()->error_count() > 0
2985 || issue_undefined_symbol_error(gsym));
2988 this->tls_gd_to_le(relinfo, relnum, tls_segment,
2989 rel, r_type, value, view,
2995 unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE
2996 ? GOT_TYPE_TLS_NOFFSET
2997 : GOT_TYPE_TLS_PAIR);
2998 unsigned int got_offset;
3001 gold_assert(gsym->has_got_offset(got_type));
3002 got_offset = gsym->got_offset(got_type) - target->got_size();
3006 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
3007 gold_assert(object->local_has_got_offset(r_sym, got_type));
3008 got_offset = (object->local_got_offset(r_sym, got_type)
3009 - target->got_size());
3011 if (optimized_type == tls::TLSOPT_TO_IE)
3013 this->tls_gd_to_ie(relinfo, relnum, tls_segment, rel, r_type,
3014 got_offset, view, view_size);
3017 else if (optimized_type == tls::TLSOPT_NONE)
3019 // Relocate the field with the offset of the pair of GOT
3021 Relocate_functions<32, false>::rel32(view, got_offset);
3025 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
3026 _("unsupported reloc %u"),
3030 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url)
3031 case elfcpp::R_386_TLS_DESC_CALL:
3032 this->local_dynamic_type_ = LOCAL_DYNAMIC_GNU;
3033 if (optimized_type == tls::TLSOPT_TO_LE)
3035 if (tls_segment == NULL)
3037 gold_assert(parameters->errors()->error_count() > 0
3038 || issue_undefined_symbol_error(gsym));
3041 this->tls_desc_gd_to_le(relinfo, relnum, tls_segment,
3042 rel, r_type, value, view,
3048 unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE
3049 ? GOT_TYPE_TLS_NOFFSET
3050 : GOT_TYPE_TLS_DESC);
3051 unsigned int got_offset = 0;
3052 if (r_type == elfcpp::R_386_TLS_GOTDESC
3053 && optimized_type == tls::TLSOPT_NONE)
3055 // We created GOT entries in the .got.tlsdesc portion of
3056 // the .got.plt section, but the offset stored in the
3057 // symbol is the offset within .got.tlsdesc.
3058 got_offset = (target->got_size()
3059 + target->got_plt_section()->data_size());
3063 gold_assert(gsym->has_got_offset(got_type));
3064 got_offset += gsym->got_offset(got_type) - target->got_size();
3068 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
3069 gold_assert(object->local_has_got_offset(r_sym, got_type));
3070 got_offset += (object->local_got_offset(r_sym, got_type)
3071 - target->got_size());
3073 if (optimized_type == tls::TLSOPT_TO_IE)
3075 if (tls_segment == NULL)
3077 gold_assert(parameters->errors()->error_count() > 0
3078 || issue_undefined_symbol_error(gsym));
3081 this->tls_desc_gd_to_ie(relinfo, relnum, tls_segment, rel, r_type,
3082 got_offset, view, view_size);
3085 else if (optimized_type == tls::TLSOPT_NONE)
3087 if (r_type == elfcpp::R_386_TLS_GOTDESC)
3089 // Relocate the field with the offset of the pair of GOT
3091 Relocate_functions<32, false>::rel32(view, got_offset);
3096 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
3097 _("unsupported reloc %u"),
3101 case elfcpp::R_386_TLS_LDM: // Local-dynamic
3102 if (this->local_dynamic_type_ == LOCAL_DYNAMIC_SUN)
3104 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
3105 _("both SUN and GNU model "
3106 "TLS relocations"));
3109 this->local_dynamic_type_ = LOCAL_DYNAMIC_GNU;
3110 if (optimized_type == tls::TLSOPT_TO_LE)
3112 if (tls_segment == NULL)
3114 gold_assert(parameters->errors()->error_count() > 0
3115 || issue_undefined_symbol_error(gsym));
3118 this->tls_ld_to_le(relinfo, relnum, tls_segment, rel, r_type,
3119 value, view, view_size);
3122 else if (optimized_type == tls::TLSOPT_NONE)
3124 // Relocate the field with the offset of the GOT entry for
3125 // the module index.
3126 unsigned int got_offset;
3127 got_offset = (target->got_mod_index_entry(NULL, NULL, NULL)
3128 - target->got_size());
3129 Relocate_functions<32, false>::rel32(view, got_offset);
3132 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
3133 _("unsupported reloc %u"),
3137 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
3138 if (optimized_type == tls::TLSOPT_TO_LE)
3140 // This reloc can appear in debugging sections, in which
3141 // case we must not convert to local-exec. We decide what
3142 // to do based on whether the section is marked as
3143 // containing executable code. That is what the GNU linker
3145 elfcpp::Shdr<32, false> shdr(relinfo->data_shdr);
3146 if ((shdr.get_sh_flags() & elfcpp::SHF_EXECINSTR) != 0)
3148 if (tls_segment == NULL)
3150 gold_assert(parameters->errors()->error_count() > 0
3151 || issue_undefined_symbol_error(gsym));
3154 value -= tls_segment->memsz();
3157 Relocate_functions<32, false>::rel32(view, value);
3160 case elfcpp::R_386_TLS_IE: // Initial-exec
3161 case elfcpp::R_386_TLS_GOTIE:
3162 case elfcpp::R_386_TLS_IE_32:
3163 if (optimized_type == tls::TLSOPT_TO_LE)
3165 if (tls_segment == NULL)
3167 gold_assert(parameters->errors()->error_count() > 0
3168 || issue_undefined_symbol_error(gsym));
3171 Target_i386::Relocate::tls_ie_to_le(relinfo, relnum, tls_segment,
3172 rel, r_type, value, view,
3176 else if (optimized_type == tls::TLSOPT_NONE)
3178 // Relocate the field with the offset of the GOT entry for
3179 // the tp-relative offset of the symbol.
3180 unsigned int got_type = (r_type == elfcpp::R_386_TLS_IE_32
3181 ? GOT_TYPE_TLS_OFFSET
3182 : GOT_TYPE_TLS_NOFFSET);
3183 unsigned int got_offset;
3186 gold_assert(gsym->has_got_offset(got_type));
3187 got_offset = gsym->got_offset(got_type);
3191 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
3192 gold_assert(object->local_has_got_offset(r_sym, got_type));
3193 got_offset = object->local_got_offset(r_sym, got_type);
3195 // For the R_386_TLS_IE relocation, we need to apply the
3196 // absolute address of the GOT entry.
3197 if (r_type == elfcpp::R_386_TLS_IE)
3198 got_offset += target->got_plt_section()->address();
3199 // All GOT offsets are relative to the end of the GOT.
3200 got_offset -= target->got_size();
3201 Relocate_functions<32, false>::rel32(view, got_offset);
3204 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
3205 _("unsupported reloc %u"),
3209 case elfcpp::R_386_TLS_LE: // Local-exec
3210 // If we're creating a shared library, a dynamic relocation will
3211 // have been created for this location, so do not apply it now.
3212 if (!parameters->options().shared())
3214 if (tls_segment == NULL)
3216 gold_assert(parameters->errors()->error_count() > 0
3217 || issue_undefined_symbol_error(gsym));
3220 value -= tls_segment->memsz();
3221 Relocate_functions<32, false>::rel32(view, value);
3225 case elfcpp::R_386_TLS_LE_32:
3226 // If we're creating a shared library, a dynamic relocation will
3227 // have been created for this location, so do not apply it now.
3228 if (!parameters->options().shared())
3230 if (tls_segment == NULL)
3232 gold_assert(parameters->errors()->error_count() > 0
3233 || issue_undefined_symbol_error(gsym));
3236 value = tls_segment->memsz() - value;
3237 Relocate_functions<32, false>::rel32(view, value);
3243 // Do a relocation in which we convert a TLS General-Dynamic to a
3247 Target_i386::Relocate::tls_gd_to_le(const Relocate_info<32, false>* relinfo,
3249 Output_segment* tls_segment,
3250 const elfcpp::Rel<32, false>& rel,
3252 elfcpp::Elf_types<32>::Elf_Addr value,
3253 unsigned char* view,
3254 section_size_type view_size)
3256 // leal foo(,%reg,1),%eax; call ___tls_get_addr
3257 // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
3258 // leal foo(%reg),%eax; call ___tls_get_addr
3259 // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
3261 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
3262 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 9);
3264 unsigned char op1 = view[-1];
3265 unsigned char op2 = view[-2];
3267 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3268 op2 == 0x8d || op2 == 0x04);
3269 tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[4] == 0xe8);
3275 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -3);
3276 tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[-3] == 0x8d);
3277 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3278 ((op1 & 0xc7) == 0x05 && op1 != (4 << 3)));
3279 memcpy(view - 3, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
3283 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3284 (op1 & 0xf8) == 0x80 && (op1 & 7) != 4);
3285 if (rel.get_r_offset() + 9 < view_size
3288 // There is a trailing nop. Use the size byte subl.
3289 memcpy(view - 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
3294 // Use the five byte subl.
3295 memcpy(view - 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
3299 value = tls_segment->memsz() - value;
3300 Relocate_functions<32, false>::rel32(view + roff, value);
3302 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3304 this->skip_call_tls_get_addr_ = true;
3307 // Do a relocation in which we convert a TLS General-Dynamic to an
3311 Target_i386::Relocate::tls_gd_to_ie(const Relocate_info<32, false>* relinfo,
3314 const elfcpp::Rel<32, false>& rel,
3316 elfcpp::Elf_types<32>::Elf_Addr value,
3317 unsigned char* view,
3318 section_size_type view_size)
3320 // leal foo(,%ebx,1),%eax; call ___tls_get_addr
3321 // ==> movl %gs:0,%eax; addl foo@gotntpoff(%ebx),%eax
3322 // leal foo(%ebx),%eax; call ___tls_get_addr; nop
3323 // ==> movl %gs:0,%eax; addl foo@gotntpoff(%ebx),%eax
3325 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
3326 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 9);
3328 unsigned char op1 = view[-1];
3329 unsigned char op2 = view[-2];
3331 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3332 op2 == 0x8d || op2 == 0x04);
3333 tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[4] == 0xe8);
3339 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -3);
3340 tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[-3] == 0x8d);
3341 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3342 ((op1 & 0xc7) == 0x05 && op1 != (4 << 3)));
3347 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 10);
3348 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3349 (op1 & 0xf8) == 0x80 && (op1 & 7) != 4);
3350 tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[9] == 0x90);
3354 memcpy(view + roff - 8, "\x65\xa1\0\0\0\0\x03\x83\0\0\0", 12);
3355 Relocate_functions<32, false>::rel32(view + roff, value);
3357 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3359 this->skip_call_tls_get_addr_ = true;
3362 // Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL
3363 // General-Dynamic to a Local-Exec.
3366 Target_i386::Relocate::tls_desc_gd_to_le(
3367 const Relocate_info<32, false>* relinfo,
3369 Output_segment* tls_segment,
3370 const elfcpp::Rel<32, false>& rel,
3371 unsigned int r_type,
3372 elfcpp::Elf_types<32>::Elf_Addr value,
3373 unsigned char* view,
3374 section_size_type view_size)
3376 if (r_type == elfcpp::R_386_TLS_GOTDESC)
3378 // leal foo@TLSDESC(%ebx), %eax
3379 // ==> leal foo@NTPOFF, %eax
3380 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
3381 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4);
3382 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3383 view[-2] == 0x8d && view[-1] == 0x83);
3385 value -= tls_segment->memsz();
3386 Relocate_functions<32, false>::rel32(view, value);
3390 // call *foo@TLSCALL(%eax)
3392 gold_assert(r_type == elfcpp::R_386_TLS_DESC_CALL);
3393 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 2);
3394 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3395 view[0] == 0xff && view[1] == 0x10);
3401 // Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL
3402 // General-Dynamic to an Initial-Exec.
3405 Target_i386::Relocate::tls_desc_gd_to_ie(
3406 const Relocate_info<32, false>* relinfo,
3409 const elfcpp::Rel<32, false>& rel,
3410 unsigned int r_type,
3411 elfcpp::Elf_types<32>::Elf_Addr value,
3412 unsigned char* view,
3413 section_size_type view_size)
3415 if (r_type == elfcpp::R_386_TLS_GOTDESC)
3417 // leal foo@TLSDESC(%ebx), %eax
3418 // ==> movl foo@GOTNTPOFF(%ebx), %eax
3419 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
3420 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4);
3421 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3422 view[-2] == 0x8d && view[-1] == 0x83);
3424 Relocate_functions<32, false>::rel32(view, value);
3428 // call *foo@TLSCALL(%eax)
3430 gold_assert(r_type == elfcpp::R_386_TLS_DESC_CALL);
3431 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 2);
3432 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3433 view[0] == 0xff && view[1] == 0x10);
3439 // Do a relocation in which we convert a TLS Local-Dynamic to a
3443 Target_i386::Relocate::tls_ld_to_le(const Relocate_info<32, false>* relinfo,
3446 const elfcpp::Rel<32, false>& rel,
3448 elfcpp::Elf_types<32>::Elf_Addr,
3449 unsigned char* view,
3450 section_size_type view_size)
3452 // leal foo(%reg), %eax; call ___tls_get_addr
3453 // ==> movl %gs:0,%eax; nop; leal 0(%esi,1),%esi
3455 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
3456 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 9);
3458 // FIXME: Does this test really always pass?
3459 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3460 view[-2] == 0x8d && view[-1] == 0x83);
3462 tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[4] == 0xe8);
3464 memcpy(view - 2, "\x65\xa1\0\0\0\0\x90\x8d\x74\x26\0", 11);
3466 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3468 this->skip_call_tls_get_addr_ = true;
3471 // Do a relocation in which we convert a TLS Initial-Exec to a
3475 Target_i386::Relocate::tls_ie_to_le(const Relocate_info<32, false>* relinfo,
3477 Output_segment* tls_segment,
3478 const elfcpp::Rel<32, false>& rel,
3479 unsigned int r_type,
3480 elfcpp::Elf_types<32>::Elf_Addr value,
3481 unsigned char* view,
3482 section_size_type view_size)
3484 // We have to actually change the instructions, which means that we
3485 // need to examine the opcodes to figure out which instruction we
3487 if (r_type == elfcpp::R_386_TLS_IE)
3489 // movl %gs:XX,%eax ==> movl $YY,%eax
3490 // movl %gs:XX,%reg ==> movl $YY,%reg
3491 // addl %gs:XX,%reg ==> addl $YY,%reg
3492 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -1);
3493 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4);
3495 unsigned char op1 = view[-1];
3498 // movl XX,%eax ==> movl $YY,%eax
3503 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
3505 unsigned char op2 = view[-2];
3508 // movl XX,%reg ==> movl $YY,%reg
3509 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3510 (op1 & 0xc7) == 0x05);
3512 view[-1] = 0xc0 | ((op1 >> 3) & 7);
3514 else if (op2 == 0x03)
3516 // addl XX,%reg ==> addl $YY,%reg
3517 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3518 (op1 & 0xc7) == 0x05);
3520 view[-1] = 0xc0 | ((op1 >> 3) & 7);
3523 tls::check_tls(relinfo, relnum, rel.get_r_offset(), 0);
3528 // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2
3529 // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2
3530 // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2
3531 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
3532 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4);
3534 unsigned char op1 = view[-1];
3535 unsigned char op2 = view[-2];
3536 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3537 (op1 & 0xc0) == 0x80 && (op1 & 7) != 4);
3540 // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2
3542 view[-1] = 0xc0 | ((op1 >> 3) & 7);
3544 else if (op2 == 0x2b)
3546 // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2
3548 view[-1] = 0xe8 | ((op1 >> 3) & 7);
3550 else if (op2 == 0x03)
3552 // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2
3554 view[-1] = 0xc0 | ((op1 >> 3) & 7);
3557 tls::check_tls(relinfo, relnum, rel.get_r_offset(), 0);
3560 value = tls_segment->memsz() - value;
3561 if (r_type == elfcpp::R_386_TLS_IE || r_type == elfcpp::R_386_TLS_GOTIE)
3564 Relocate_functions<32, false>::rel32(view, value);
3567 // Relocate section data.
3570 Target_i386::relocate_section(const Relocate_info<32, false>* relinfo,
3571 unsigned int sh_type,
3572 const unsigned char* prelocs,
3574 Output_section* output_section,
3575 bool needs_special_offset_handling,
3576 unsigned char* view,
3577 elfcpp::Elf_types<32>::Elf_Addr address,
3578 section_size_type view_size,
3579 const Reloc_symbol_changes* reloc_symbol_changes)
3581 gold_assert(sh_type == elfcpp::SHT_REL);
3583 gold::relocate_section<32, false, Target_i386, elfcpp::SHT_REL,
3584 Target_i386::Relocate, gold::Default_comdat_behavior>(
3590 needs_special_offset_handling,
3594 reloc_symbol_changes);
3597 // Return the size of a relocation while scanning during a relocatable
3601 Target_i386::Relocatable_size_for_reloc::get_size_for_reloc(
3602 unsigned int r_type,
3607 case elfcpp::R_386_NONE:
3608 case elfcpp::R_386_GNU_VTINHERIT:
3609 case elfcpp::R_386_GNU_VTENTRY:
3610 case elfcpp::R_386_TLS_GD: // Global-dynamic
3611 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url)
3612 case elfcpp::R_386_TLS_DESC_CALL:
3613 case elfcpp::R_386_TLS_LDM: // Local-dynamic
3614 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
3615 case elfcpp::R_386_TLS_IE: // Initial-exec
3616 case elfcpp::R_386_TLS_IE_32:
3617 case elfcpp::R_386_TLS_GOTIE:
3618 case elfcpp::R_386_TLS_LE: // Local-exec
3619 case elfcpp::R_386_TLS_LE_32:
3622 case elfcpp::R_386_32:
3623 case elfcpp::R_386_PC32:
3624 case elfcpp::R_386_GOT32:
3625 case elfcpp::R_386_GOT32X:
3626 case elfcpp::R_386_PLT32:
3627 case elfcpp::R_386_GOTOFF:
3628 case elfcpp::R_386_GOTPC:
3631 case elfcpp::R_386_16:
3632 case elfcpp::R_386_PC16:
3635 case elfcpp::R_386_8:
3636 case elfcpp::R_386_PC8:
3639 // These are relocations which should only be seen by the
3640 // dynamic linker, and should never be seen here.
3641 case elfcpp::R_386_COPY:
3642 case elfcpp::R_386_GLOB_DAT:
3643 case elfcpp::R_386_JUMP_SLOT:
3644 case elfcpp::R_386_RELATIVE:
3645 case elfcpp::R_386_IRELATIVE:
3646 case elfcpp::R_386_TLS_TPOFF:
3647 case elfcpp::R_386_TLS_DTPMOD32:
3648 case elfcpp::R_386_TLS_DTPOFF32:
3649 case elfcpp::R_386_TLS_TPOFF32:
3650 case elfcpp::R_386_TLS_DESC:
3651 object->error(_("unexpected reloc %u in object file"), r_type);
3654 case elfcpp::R_386_32PLT:
3655 case elfcpp::R_386_TLS_GD_32:
3656 case elfcpp::R_386_TLS_GD_PUSH:
3657 case elfcpp::R_386_TLS_GD_CALL:
3658 case elfcpp::R_386_TLS_GD_POP:
3659 case elfcpp::R_386_TLS_LDM_32:
3660 case elfcpp::R_386_TLS_LDM_PUSH:
3661 case elfcpp::R_386_TLS_LDM_CALL:
3662 case elfcpp::R_386_TLS_LDM_POP:
3663 case elfcpp::R_386_USED_BY_INTEL_200:
3665 object->error(_("unsupported reloc %u in object file"), r_type);
3670 // Scan the relocs during a relocatable link.
3673 Target_i386::scan_relocatable_relocs(Symbol_table* symtab,
3675 Sized_relobj_file<32, false>* object,
3676 unsigned int data_shndx,
3677 unsigned int sh_type,
3678 const unsigned char* prelocs,
3680 Output_section* output_section,
3681 bool needs_special_offset_handling,
3682 size_t local_symbol_count,
3683 const unsigned char* plocal_symbols,
3684 Relocatable_relocs* rr)
3686 gold_assert(sh_type == elfcpp::SHT_REL);
3688 typedef gold::Default_scan_relocatable_relocs<elfcpp::SHT_REL,
3689 Relocatable_size_for_reloc> Scan_relocatable_relocs;
3691 gold::scan_relocatable_relocs<32, false, elfcpp::SHT_REL,
3692 Scan_relocatable_relocs>(
3700 needs_special_offset_handling,
3706 // Emit relocations for a section.
3709 Target_i386::relocate_relocs(
3710 const Relocate_info<32, false>* relinfo,
3711 unsigned int sh_type,
3712 const unsigned char* prelocs,
3714 Output_section* output_section,
3715 elfcpp::Elf_types<32>::Elf_Off offset_in_output_section,
3716 const Relocatable_relocs* rr,
3717 unsigned char* view,
3718 elfcpp::Elf_types<32>::Elf_Addr view_address,
3719 section_size_type view_size,
3720 unsigned char* reloc_view,
3721 section_size_type reloc_view_size)
3723 gold_assert(sh_type == elfcpp::SHT_REL);
3725 gold::relocate_relocs<32, false, elfcpp::SHT_REL>(
3730 offset_in_output_section,
3739 // Return the value to use for a dynamic which requires special
3740 // treatment. This is how we support equality comparisons of function
3741 // pointers across shared library boundaries, as described in the
3742 // processor specific ABI supplement.
3745 Target_i386::do_dynsym_value(const Symbol* gsym) const
3747 gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset());
3748 return this->plt_address_for_global(gsym);
3751 // Return a string used to fill a code section with nops to take up
3752 // the specified length.
3755 Target_i386::do_code_fill(section_size_type length) const
3759 // Build a jmp instruction to skip over the bytes.
3760 unsigned char jmp[5];
3762 elfcpp::Swap_unaligned<32, false>::writeval(jmp + 1, length - 5);
3763 return (std::string(reinterpret_cast<char*>(&jmp[0]), 5)
3764 + std::string(length - 5, static_cast<char>(0x90)));
3767 // Nop sequences of various lengths.
3768 const char nop1[1] = { '\x90' }; // nop
3769 const char nop2[2] = { '\x66', '\x90' }; // xchg %ax %ax
3770 const char nop3[3] = { '\x8d', '\x76', '\x00' }; // leal 0(%esi),%esi
3771 const char nop4[4] = { '\x8d', '\x74', '\x26', // leal 0(%esi,1),%esi
3773 const char nop5[5] = { '\x90', '\x8d', '\x74', // nop
3774 '\x26', '\x00' }; // leal 0(%esi,1),%esi
3775 const char nop6[6] = { '\x8d', '\xb6', '\x00', // leal 0L(%esi),%esi
3776 '\x00', '\x00', '\x00' };
3777 const char nop7[7] = { '\x8d', '\xb4', '\x26', // leal 0L(%esi,1),%esi
3778 '\x00', '\x00', '\x00',
3780 const char nop8[8] = { '\x90', '\x8d', '\xb4', // nop
3781 '\x26', '\x00', '\x00', // leal 0L(%esi,1),%esi
3783 const char nop9[9] = { '\x89', '\xf6', '\x8d', // movl %esi,%esi
3784 '\xbc', '\x27', '\x00', // leal 0L(%edi,1),%edi
3785 '\x00', '\x00', '\x00' };
3786 const char nop10[10] = { '\x8d', '\x76', '\x00', // leal 0(%esi),%esi
3787 '\x8d', '\xbc', '\x27', // leal 0L(%edi,1),%edi
3788 '\x00', '\x00', '\x00',
3790 const char nop11[11] = { '\x8d', '\x74', '\x26', // leal 0(%esi,1),%esi
3791 '\x00', '\x8d', '\xbc', // leal 0L(%edi,1),%edi
3792 '\x27', '\x00', '\x00',
3794 const char nop12[12] = { '\x8d', '\xb6', '\x00', // leal 0L(%esi),%esi
3795 '\x00', '\x00', '\x00', // leal 0L(%edi),%edi
3796 '\x8d', '\xbf', '\x00',
3797 '\x00', '\x00', '\x00' };
3798 const char nop13[13] = { '\x8d', '\xb6', '\x00', // leal 0L(%esi),%esi
3799 '\x00', '\x00', '\x00', // leal 0L(%edi,1),%edi
3800 '\x8d', '\xbc', '\x27',
3801 '\x00', '\x00', '\x00',
3803 const char nop14[14] = { '\x8d', '\xb4', '\x26', // leal 0L(%esi,1),%esi
3804 '\x00', '\x00', '\x00', // leal 0L(%edi,1),%edi
3805 '\x00', '\x8d', '\xbc',
3806 '\x27', '\x00', '\x00',
3808 const char nop15[15] = { '\xeb', '\x0d', '\x90', // jmp .+15
3809 '\x90', '\x90', '\x90', // nop,nop,nop,...
3810 '\x90', '\x90', '\x90',
3811 '\x90', '\x90', '\x90',
3812 '\x90', '\x90', '\x90' };
3814 const char* nops[16] = {
3816 nop1, nop2, nop3, nop4, nop5, nop6, nop7,
3817 nop8, nop9, nop10, nop11, nop12, nop13, nop14, nop15
3820 return std::string(nops[length], length);
3823 // Return the value to use for the base of a DW_EH_PE_datarel offset
3824 // in an FDE. Solaris and SVR4 use DW_EH_PE_datarel because their
3825 // assembler can not write out the difference between two labels in
3826 // different sections, so instead of using a pc-relative value they
3827 // use an offset from the GOT.
3830 Target_i386::do_ehframe_datarel_base() const
3832 gold_assert(this->global_offset_table_ != NULL);
3833 Symbol* sym = this->global_offset_table_;
3834 Sized_symbol<32>* ssym = static_cast<Sized_symbol<32>*>(sym);
3835 return ssym->value();
3838 // Return whether SYM should be treated as a call to a non-split
3839 // function. We don't want that to be true of a call to a
3840 // get_pc_thunk function.
3843 Target_i386::do_is_call_to_non_split(const Symbol* sym, unsigned int) const
3845 return (sym->type() == elfcpp::STT_FUNC
3846 && !is_prefix_of("__i686.get_pc_thunk.", sym->name()));
3849 // FNOFFSET in section SHNDX in OBJECT is the start of a function
3850 // compiled with -fsplit-stack. The function calls non-split-stack
3851 // code. We have to change the function so that it always ensures
3852 // that it has enough stack space to run some random function.
3855 Target_i386::do_calls_non_split(Relobj* object, unsigned int shndx,
3856 section_offset_type fnoffset,
3857 section_size_type fnsize,
3858 unsigned char* view,
3859 section_size_type view_size,
3861 std::string* to) const
3863 // The function starts with a comparison of the stack pointer and a
3864 // field in the TCB. This is followed by a jump.
3867 if (this->match_view(view, view_size, fnoffset, "\x65\x3b\x25", 3)
3870 // We will call __morestack if the carry flag is set after this
3871 // comparison. We turn the comparison into an stc instruction
3873 view[fnoffset] = '\xf9';
3874 this->set_view_to_nop(view, view_size, fnoffset + 1, 6);
3876 // lea NN(%esp),%ecx
3877 // lea NN(%esp),%edx
3878 else if ((this->match_view(view, view_size, fnoffset, "\x8d\x8c\x24", 3)
3879 || this->match_view(view, view_size, fnoffset, "\x8d\x94\x24", 3))
3882 // This is loading an offset from the stack pointer for a
3883 // comparison. The offset is negative, so we decrease the
3884 // offset by the amount of space we need for the stack. This
3885 // means we will avoid calling __morestack if there happens to
3886 // be plenty of space on the stack already.
3887 unsigned char* pval = view + fnoffset + 3;
3888 uint32_t val = elfcpp::Swap_unaligned<32, false>::readval(pval);
3889 val -= parameters->options().split_stack_adjust_size();
3890 elfcpp::Swap_unaligned<32, false>::writeval(pval, val);
3894 if (!object->has_no_split_stack())
3895 object->error(_("failed to match split-stack sequence at "
3896 "section %u offset %0zx"),
3897 shndx, static_cast<size_t>(fnoffset));
3901 // We have to change the function so that it calls
3902 // __morestack_non_split instead of __morestack. The former will
3903 // allocate additional stack space.
3904 *from = "__morestack";
3905 *to = "__morestack_non_split";
3908 // The selector for i386 object files. Note this is never instantiated
3909 // directly. It's only used in Target_selector_i386_nacl, below.
3911 class Target_selector_i386 : public Target_selector_freebsd
3914 Target_selector_i386()
3915 : Target_selector_freebsd(elfcpp::EM_386, 32, false,
3916 "elf32-i386", "elf32-i386-freebsd",
3921 do_instantiate_target()
3922 { return new Target_i386(); }
3925 // NaCl variant. It uses different PLT contents.
3927 class Output_data_plt_i386_nacl : public Output_data_plt_i386
3930 Output_data_plt_i386_nacl(Layout* layout,
3931 Output_data_got_plt_i386* got_plt,
3932 Output_data_space* got_irelative)
3933 : Output_data_plt_i386(layout, plt_entry_size, got_plt, got_irelative)
3937 virtual unsigned int
3938 do_get_plt_entry_size() const
3939 { return plt_entry_size; }
3942 do_add_eh_frame(Layout* layout)
3944 layout->add_eh_frame_for_plt(this, plt_eh_frame_cie, plt_eh_frame_cie_size,
3945 plt_eh_frame_fde, plt_eh_frame_fde_size);
3948 // The size of an entry in the PLT.
3949 static const int plt_entry_size = 64;
3951 // The .eh_frame unwind information for the PLT.
3952 static const int plt_eh_frame_fde_size = 32;
3953 static const unsigned char plt_eh_frame_fde[plt_eh_frame_fde_size];
3956 class Output_data_plt_i386_nacl_exec : public Output_data_plt_i386_nacl
3959 Output_data_plt_i386_nacl_exec(Layout* layout,
3960 Output_data_got_plt_i386* got_plt,
3961 Output_data_space* got_irelative)
3962 : Output_data_plt_i386_nacl(layout, got_plt, got_irelative)
3967 do_fill_first_plt_entry(unsigned char* pov,
3968 elfcpp::Elf_types<32>::Elf_Addr got_address);
3970 virtual unsigned int
3971 do_fill_plt_entry(unsigned char* pov,
3972 elfcpp::Elf_types<32>::Elf_Addr got_address,
3973 unsigned int got_offset,
3974 unsigned int plt_offset,
3975 unsigned int plt_rel_offset);
3978 // The first entry in the PLT for an executable.
3979 static const unsigned char first_plt_entry[plt_entry_size];
3981 // Other entries in the PLT for an executable.
3982 static const unsigned char plt_entry[plt_entry_size];
3985 class Output_data_plt_i386_nacl_dyn : public Output_data_plt_i386_nacl
3988 Output_data_plt_i386_nacl_dyn(Layout* layout,
3989 Output_data_got_plt_i386* got_plt,
3990 Output_data_space* got_irelative)
3991 : Output_data_plt_i386_nacl(layout, got_plt, got_irelative)
3996 do_fill_first_plt_entry(unsigned char* pov, elfcpp::Elf_types<32>::Elf_Addr);
3998 virtual unsigned int
3999 do_fill_plt_entry(unsigned char* pov,
4000 elfcpp::Elf_types<32>::Elf_Addr,
4001 unsigned int got_offset,
4002 unsigned int plt_offset,
4003 unsigned int plt_rel_offset);
4006 // The first entry in the PLT for a shared object.
4007 static const unsigned char first_plt_entry[plt_entry_size];
4009 // Other entries in the PLT for a shared object.
4010 static const unsigned char plt_entry[plt_entry_size];
4013 class Target_i386_nacl : public Target_i386
4017 : Target_i386(&i386_nacl_info)
4021 virtual Output_data_plt_i386*
4022 do_make_data_plt(Layout* layout,
4023 Output_data_got_plt_i386* got_plt,
4024 Output_data_space* got_irelative,
4028 return new Output_data_plt_i386_nacl_dyn(layout, got_plt, got_irelative);
4030 return new Output_data_plt_i386_nacl_exec(layout, got_plt, got_irelative);
4034 do_code_fill(section_size_type length) const;
4037 static const Target::Target_info i386_nacl_info;
4040 const Target::Target_info Target_i386_nacl::i386_nacl_info =
4043 false, // is_big_endian
4044 elfcpp::EM_386, // machine_code
4045 false, // has_make_symbol
4046 false, // has_resolve
4047 true, // has_code_fill
4048 true, // is_default_stack_executable
4049 true, // can_icf_inline_merge_sections
4051 "/lib/ld-nacl-x86-32.so.1", // dynamic_linker
4052 0x20000, // default_text_segment_address
4053 0x10000, // abi_pagesize (overridable by -z max-page-size)
4054 0x10000, // common_pagesize (overridable by -z common-page-size)
4055 true, // isolate_execinstr
4056 0x10000000, // rosegment_gap
4057 elfcpp::SHN_UNDEF, // small_common_shndx
4058 elfcpp::SHN_UNDEF, // large_common_shndx
4059 0, // small_common_section_flags
4060 0, // large_common_section_flags
4061 NULL, // attributes_section
4062 NULL, // attributes_vendor
4063 "_start" // entry_symbol_name
4066 #define NACLMASK 0xe0 // 32-byte alignment mask
4069 Output_data_plt_i386_nacl_exec::first_plt_entry[plt_entry_size] =
4071 0xff, 0x35, // pushl contents of memory address
4072 0, 0, 0, 0, // replaced with address of .got + 4
4073 0x8b, 0x0d, // movl contents of address, %ecx
4074 0, 0, 0, 0, // replaced with address of .got + 8
4075 0x83, 0xe1, NACLMASK, // andl $NACLMASK, %ecx
4076 0xff, 0xe1, // jmp *%ecx
4077 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4078 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4079 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4080 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4081 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4082 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4083 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4084 0x90, 0x90, 0x90, 0x90, 0x90
4088 Output_data_plt_i386_nacl_exec::do_fill_first_plt_entry(
4090 elfcpp::Elf_types<32>::Elf_Addr got_address)
4092 memcpy(pov, first_plt_entry, plt_entry_size);
4093 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_address + 4);
4094 elfcpp::Swap<32, false>::writeval(pov + 8, got_address + 8);
4097 // The first entry in the PLT for a shared object.
4100 Output_data_plt_i386_nacl_dyn::first_plt_entry[plt_entry_size] =
4102 0xff, 0xb3, 4, 0, 0, 0, // pushl 4(%ebx)
4103 0x8b, 0x4b, 0x08, // mov 0x8(%ebx), %ecx
4104 0x83, 0xe1, NACLMASK, // andl $NACLMASK, %ecx
4105 0xff, 0xe1, // jmp *%ecx
4106 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4107 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4108 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4109 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4110 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4111 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4112 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4113 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4114 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4115 0x90, 0x90, 0x90, 0x90, 0x90 // nops
4119 Output_data_plt_i386_nacl_dyn::do_fill_first_plt_entry(
4121 elfcpp::Elf_types<32>::Elf_Addr)
4123 memcpy(pov, first_plt_entry, plt_entry_size);
4126 // Subsequent entries in the PLT for an executable.
4129 Output_data_plt_i386_nacl_exec::plt_entry[plt_entry_size] =
4131 0x8b, 0x0d, // movl contents of address, %ecx */
4132 0, 0, 0, 0, // replaced with address of symbol in .got
4133 0x83, 0xe1, NACLMASK, // andl $NACLMASK, %ecx
4134 0xff, 0xe1, // jmp *%ecx
4136 // Pad to the next 32-byte boundary with nop instructions.
4138 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4139 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4141 // Lazy GOT entries point here (32-byte aligned).
4142 0x68, // pushl immediate
4143 0, 0, 0, 0, // replaced with offset into relocation table
4144 0xe9, // jmp relative
4145 0, 0, 0, 0, // replaced with offset to start of .plt
4147 // Pad to the next 32-byte boundary with nop instructions.
4148 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4149 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4154 Output_data_plt_i386_nacl_exec::do_fill_plt_entry(
4156 elfcpp::Elf_types<32>::Elf_Addr got_address,
4157 unsigned int got_offset,
4158 unsigned int plt_offset,
4159 unsigned int plt_rel_offset)
4161 memcpy(pov, plt_entry, plt_entry_size);
4162 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
4163 got_address + got_offset);
4164 elfcpp::Swap_unaligned<32, false>::writeval(pov + 33, plt_rel_offset);
4165 elfcpp::Swap<32, false>::writeval(pov + 38, - (plt_offset + 38 + 4));
4169 // Subsequent entries in the PLT for a shared object.
4172 Output_data_plt_i386_nacl_dyn::plt_entry[plt_entry_size] =
4174 0x8b, 0x8b, // movl offset(%ebx), %ecx
4175 0, 0, 0, 0, // replaced with offset of symbol in .got
4176 0x83, 0xe1, 0xe0, // andl $NACLMASK, %ecx
4177 0xff, 0xe1, // jmp *%ecx
4179 // Pad to the next 32-byte boundary with nop instructions.
4181 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4182 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4184 // Lazy GOT entries point here (32-byte aligned).
4185 0x68, // pushl immediate
4186 0, 0, 0, 0, // replaced with offset into relocation table.
4187 0xe9, // jmp relative
4188 0, 0, 0, 0, // replaced with offset to start of .plt.
4190 // Pad to the next 32-byte boundary with nop instructions.
4191 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4192 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4197 Output_data_plt_i386_nacl_dyn::do_fill_plt_entry(
4199 elfcpp::Elf_types<32>::Elf_Addr,
4200 unsigned int got_offset,
4201 unsigned int plt_offset,
4202 unsigned int plt_rel_offset)
4204 memcpy(pov, plt_entry, plt_entry_size);
4205 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_offset);
4206 elfcpp::Swap_unaligned<32, false>::writeval(pov + 33, plt_rel_offset);
4207 elfcpp::Swap<32, false>::writeval(pov + 38, - (plt_offset + 38 + 4));
4212 Output_data_plt_i386_nacl::plt_eh_frame_fde[plt_eh_frame_fde_size] =
4214 0, 0, 0, 0, // Replaced with offset to .plt.
4215 0, 0, 0, 0, // Replaced with size of .plt.
4216 0, // Augmentation size.
4217 elfcpp::DW_CFA_def_cfa_offset, 8, // DW_CFA_def_cfa_offset: 8.
4218 elfcpp::DW_CFA_advance_loc + 6, // Advance 6 to __PLT__ + 6.
4219 elfcpp::DW_CFA_def_cfa_offset, 12, // DW_CFA_def_cfa_offset: 12.
4220 elfcpp::DW_CFA_advance_loc + 58, // Advance 58 to __PLT__ + 64.
4221 elfcpp::DW_CFA_def_cfa_expression, // DW_CFA_def_cfa_expression.
4222 13, // Block length.
4223 elfcpp::DW_OP_breg4, 4, // Push %esp + 4.
4224 elfcpp::DW_OP_breg8, 0, // Push %eip.
4225 elfcpp::DW_OP_const1u, 63, // Push 0x3f.
4226 elfcpp::DW_OP_and, // & (%eip & 0x3f).
4227 elfcpp::DW_OP_const1u, 37, // Push 0x25.
4228 elfcpp::DW_OP_ge, // >= ((%eip & 0x3f) >= 0x25)
4229 elfcpp::DW_OP_lit2, // Push 2.
4230 elfcpp::DW_OP_shl, // << (((%eip & 0x3f) >= 0x25) << 2)
4231 elfcpp::DW_OP_plus, // + ((((%eip&0x3f)>=0x25)<<2)+%esp+4
4232 elfcpp::DW_CFA_nop, // Align to 32 bytes.
4236 // Return a string used to fill a code section with nops.
4237 // For NaCl, long NOPs are only valid if they do not cross
4238 // bundle alignment boundaries, so keep it simple with one-byte NOPs.
4240 Target_i386_nacl::do_code_fill(section_size_type length) const
4242 return std::string(length, static_cast<char>(0x90));
4245 // The selector for i386-nacl object files.
4247 class Target_selector_i386_nacl
4248 : public Target_selector_nacl<Target_selector_i386, Target_i386_nacl>
4251 Target_selector_i386_nacl()
4252 : Target_selector_nacl<Target_selector_i386,
4253 Target_i386_nacl>("x86-32",
4259 Target_selector_i386_nacl target_selector_i386;
4261 // IAMCU variant. It uses EM_IAMCU, not EM_386.
4263 class Target_iamcu : public Target_i386
4267 : Target_i386(&iamcu_info)
4271 // Information about this specific target which we pass to the
4272 // general Target structure.
4273 static const Target::Target_info iamcu_info;
4276 const Target::Target_info Target_iamcu::iamcu_info =
4279 false, // is_big_endian
4280 elfcpp::EM_IAMCU, // machine_code
4281 false, // has_make_symbol
4282 false, // has_resolve
4283 true, // has_code_fill
4284 true, // is_default_stack_executable
4285 true, // can_icf_inline_merge_sections
4287 "/usr/lib/libc.so.1", // dynamic_linker
4288 0x08048000, // default_text_segment_address
4289 0x1000, // abi_pagesize (overridable by -z max-page-size)
4290 0x1000, // common_pagesize (overridable by -z common-page-size)
4291 false, // isolate_execinstr
4293 elfcpp::SHN_UNDEF, // small_common_shndx
4294 elfcpp::SHN_UNDEF, // large_common_shndx
4295 0, // small_common_section_flags
4296 0, // large_common_section_flags
4297 NULL, // attributes_section
4298 NULL, // attributes_vendor
4299 "_start" // entry_symbol_name
4302 class Target_selector_iamcu : public Target_selector
4305 Target_selector_iamcu()
4306 : Target_selector(elfcpp::EM_IAMCU, 32, false, "elf32-iamcu",
4311 do_instantiate_target()
4312 { return new Target_iamcu(); }
4315 Target_selector_iamcu target_selector_iamcu;
4317 } // End anonymous namespace.