1 // i386.cc -- i386 target support for gold.
3 // Copyright (C) 2006-2017 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 // Scan the relocs for --emit-relocs.
434 emit_relocs_scan(Symbol_table* symtab,
436 Sized_relobj_file<32, false>* object,
437 unsigned int data_shndx,
438 unsigned int sh_type,
439 const unsigned char* prelocs,
441 Output_section* output_section,
442 bool needs_special_offset_handling,
443 size_t local_symbol_count,
444 const unsigned char* plocal_syms,
445 Relocatable_relocs* rr);
447 // Emit relocations for a section.
449 relocate_relocs(const Relocate_info<32, false>*,
450 unsigned int sh_type,
451 const unsigned char* prelocs,
453 Output_section* output_section,
454 elfcpp::Elf_types<32>::Elf_Off offset_in_output_section,
456 elfcpp::Elf_types<32>::Elf_Addr view_address,
457 section_size_type view_size,
458 unsigned char* reloc_view,
459 section_size_type reloc_view_size);
461 // Return a string used to fill a code section with nops.
463 do_code_fill(section_size_type length) const;
465 // Return whether SYM is defined by the ABI.
467 do_is_defined_by_abi(const Symbol* sym) const
468 { return strcmp(sym->name(), "___tls_get_addr") == 0; }
470 // Return whether a symbol name implies a local label. The UnixWare
471 // 2.1 cc generates temporary symbols that start with .X, so we
472 // recognize them here. FIXME: do other SVR4 compilers also use .X?.
473 // If so, we should move the .X recognition into
474 // Target::do_is_local_label_name.
476 do_is_local_label_name(const char* name) const
478 if (name[0] == '.' && name[1] == 'X')
480 return Target::do_is_local_label_name(name);
483 // Return the PLT address to use for a global symbol.
485 do_plt_address_for_global(const Symbol* gsym) const
486 { return this->plt_section()->address_for_global(gsym); }
489 do_plt_address_for_local(const Relobj* relobj, unsigned int symndx) const
490 { return this->plt_section()->address_for_local(relobj, symndx); }
492 // We can tell whether we take the address of a function.
494 do_can_check_for_function_pointers() const
497 // Return the base for a DW_EH_PE_datarel encoding.
499 do_ehframe_datarel_base() const;
501 // Return whether SYM is call to a non-split function.
503 do_is_call_to_non_split(const Symbol* sym, const unsigned char*,
504 const unsigned char*, section_size_type) const;
506 // Adjust -fsplit-stack code which calls non-split-stack code.
508 do_calls_non_split(Relobj* object, unsigned int shndx,
509 section_offset_type fnoffset, section_size_type fnsize,
510 const unsigned char* prelocs, size_t reloc_count,
511 unsigned char* view, section_size_type view_size,
512 std::string* from, std::string* to) const;
514 // Return the size of the GOT section.
518 gold_assert(this->got_ != NULL);
519 return this->got_->data_size();
522 // Return the number of entries in the GOT.
524 got_entry_count() const
526 if (this->got_ == NULL)
528 return this->got_size() / 4;
531 // Return the number of entries in the PLT.
533 plt_entry_count() const;
535 // Return the offset of the first non-reserved PLT entry.
537 first_plt_entry_offset() const;
539 // Return the size of each PLT entry.
541 plt_entry_size() const;
544 // Instantiate the plt_ member.
545 // This chooses the right PLT flavor for an executable or a shared object.
546 Output_data_plt_i386*
547 make_data_plt(Layout* layout,
548 Output_data_got_plt_i386* got_plt,
549 Output_data_space* got_irelative,
551 { return this->do_make_data_plt(layout, got_plt, got_irelative, dyn); }
553 virtual Output_data_plt_i386*
554 do_make_data_plt(Layout* layout,
555 Output_data_got_plt_i386* got_plt,
556 Output_data_space* got_irelative,
560 return new Output_data_plt_i386_dyn(layout, got_plt, got_irelative);
562 return new Output_data_plt_i386_exec(layout, got_plt, got_irelative);
566 // The class which scans relocations.
571 get_reference_flags(unsigned int r_type);
574 local(Symbol_table* symtab, Layout* layout, Target_i386* target,
575 Sized_relobj_file<32, false>* object,
576 unsigned int data_shndx,
577 Output_section* output_section,
578 const elfcpp::Rel<32, false>& reloc, unsigned int r_type,
579 const elfcpp::Sym<32, false>& lsym,
583 global(Symbol_table* symtab, Layout* layout, Target_i386* target,
584 Sized_relobj_file<32, false>* object,
585 unsigned int data_shndx,
586 Output_section* output_section,
587 const elfcpp::Rel<32, false>& reloc, unsigned int r_type,
591 local_reloc_may_be_function_pointer(Symbol_table* symtab, Layout* layout,
593 Sized_relobj_file<32, false>* object,
594 unsigned int data_shndx,
595 Output_section* output_section,
596 const elfcpp::Rel<32, false>& reloc,
598 const elfcpp::Sym<32, false>& lsym);
601 global_reloc_may_be_function_pointer(Symbol_table* symtab, Layout* layout,
603 Sized_relobj_file<32, false>* object,
604 unsigned int data_shndx,
605 Output_section* output_section,
606 const elfcpp::Rel<32, false>& reloc,
611 possible_function_pointer_reloc(unsigned int r_type);
614 reloc_needs_plt_for_ifunc(Sized_relobj_file<32, false>*,
615 unsigned int r_type);
618 unsupported_reloc_local(Sized_relobj_file<32, false>*, unsigned int r_type);
621 unsupported_reloc_global(Sized_relobj_file<32, false>*, unsigned int r_type,
625 // The class which implements relocation.
630 : skip_call_tls_get_addr_(false),
631 local_dynamic_type_(LOCAL_DYNAMIC_NONE)
636 if (this->skip_call_tls_get_addr_)
638 // FIXME: This needs to specify the location somehow.
639 gold_error(_("missing expected TLS relocation"));
643 // Return whether the static relocation needs to be applied.
645 should_apply_static_reloc(const Sized_symbol<32>* gsym,
648 Output_section* output_section);
650 // Do a relocation. Return false if the caller should not issue
651 // any warnings about this relocation.
653 relocate(const Relocate_info<32, false>*, unsigned int,
654 Target_i386*, Output_section*, size_t, const unsigned char*,
655 const Sized_symbol<32>*, const Symbol_value<32>*,
656 unsigned char*, elfcpp::Elf_types<32>::Elf_Addr,
660 // Do a TLS relocation.
662 relocate_tls(const Relocate_info<32, false>*, Target_i386* target,
663 size_t relnum, const elfcpp::Rel<32, false>&,
664 unsigned int r_type, const Sized_symbol<32>*,
665 const Symbol_value<32>*,
666 unsigned char*, elfcpp::Elf_types<32>::Elf_Addr,
669 // Do a TLS General-Dynamic to Initial-Exec transition.
671 tls_gd_to_ie(const Relocate_info<32, false>*, size_t relnum,
672 const elfcpp::Rel<32, false>&, unsigned int r_type,
673 elfcpp::Elf_types<32>::Elf_Addr value,
675 section_size_type view_size);
677 // Do a TLS General-Dynamic to Local-Exec transition.
679 tls_gd_to_le(const Relocate_info<32, false>*, size_t relnum,
680 Output_segment* tls_segment,
681 const elfcpp::Rel<32, false>&, unsigned int r_type,
682 elfcpp::Elf_types<32>::Elf_Addr value,
684 section_size_type view_size);
686 // Do a TLS_GOTDESC or TLS_DESC_CALL General-Dynamic to Initial-Exec
689 tls_desc_gd_to_ie(const Relocate_info<32, false>*, size_t relnum,
690 const elfcpp::Rel<32, false>&, unsigned int r_type,
691 elfcpp::Elf_types<32>::Elf_Addr value,
693 section_size_type view_size);
695 // Do a TLS_GOTDESC or TLS_DESC_CALL General-Dynamic to Local-Exec
698 tls_desc_gd_to_le(const Relocate_info<32, false>*, size_t relnum,
699 Output_segment* tls_segment,
700 const elfcpp::Rel<32, false>&, unsigned int r_type,
701 elfcpp::Elf_types<32>::Elf_Addr value,
703 section_size_type view_size);
705 // Do a TLS Local-Dynamic to Local-Exec transition.
707 tls_ld_to_le(const Relocate_info<32, false>*, size_t relnum,
708 Output_segment* tls_segment,
709 const elfcpp::Rel<32, false>&, unsigned int r_type,
710 elfcpp::Elf_types<32>::Elf_Addr value,
712 section_size_type view_size);
714 // Do a TLS Initial-Exec to Local-Exec transition.
716 tls_ie_to_le(const Relocate_info<32, false>*, size_t relnum,
717 Output_segment* tls_segment,
718 const elfcpp::Rel<32, false>&, unsigned int r_type,
719 elfcpp::Elf_types<32>::Elf_Addr value,
721 section_size_type view_size);
723 // We need to keep track of which type of local dynamic relocation
724 // we have seen, so that we can optimize R_386_TLS_LDO_32 correctly.
725 enum Local_dynamic_type
732 // This is set if we should skip the next reloc, which should be a
733 // PLT32 reloc against ___tls_get_addr.
734 bool skip_call_tls_get_addr_;
735 // The type of local dynamic relocation we have seen in the section
736 // being relocated, if any.
737 Local_dynamic_type local_dynamic_type_;
740 // A class for inquiring about properties of a relocation,
741 // used while scanning relocs during a relocatable link and
742 // garbage collection.
743 class Classify_reloc :
744 public gold::Default_classify_reloc<elfcpp::SHT_REL, 32, false>
747 typedef Reloc_types<elfcpp::SHT_REL, 32, false>::Reloc Reltype;
749 // Return the explicit addend of the relocation (return 0 for SHT_REL).
750 static elfcpp::Elf_types<32>::Elf_Swxword
751 get_r_addend(const Reltype*)
754 // Return the size of the addend of the relocation (only used for SHT_REL).
756 get_size_for_reloc(unsigned int, Relobj*);
759 // Adjust TLS relocation type based on the options and whether this
760 // is a local symbol.
761 static tls::Tls_optimization
762 optimize_tls_reloc(bool is_final, int r_type);
764 // Check if relocation against this symbol is a candidate for
766 // mov foo@GOT(%reg), %reg
768 // lea foo@GOTOFF(%reg), %reg.
770 can_convert_mov_to_lea(const Symbol* gsym)
772 gold_assert(gsym != NULL);
773 return (gsym->type() != elfcpp::STT_GNU_IFUNC
774 && !gsym->is_undefined ()
775 && !gsym->is_from_dynobj()
776 && !gsym->is_preemptible()
777 && (!parameters->options().shared()
778 || (gsym->visibility() != elfcpp::STV_DEFAULT
779 && gsym->visibility() != elfcpp::STV_PROTECTED)
780 || parameters->options().Bsymbolic())
781 && strcmp(gsym->name(), "_DYNAMIC") != 0);
784 // Get the GOT section, creating it if necessary.
785 Output_data_got<32, false>*
786 got_section(Symbol_table*, Layout*);
788 // Get the GOT PLT section.
789 Output_data_got_plt_i386*
790 got_plt_section() const
792 gold_assert(this->got_plt_ != NULL);
793 return this->got_plt_;
796 // Get the GOT section for TLSDESC entries.
797 Output_data_got<32, false>*
798 got_tlsdesc_section() const
800 gold_assert(this->got_tlsdesc_ != NULL);
801 return this->got_tlsdesc_;
804 // Create the PLT section.
806 make_plt_section(Symbol_table* symtab, Layout* layout);
808 // Create a PLT entry for a global symbol.
810 make_plt_entry(Symbol_table*, Layout*, Symbol*);
812 // Create a PLT entry for a local STT_GNU_IFUNC symbol.
814 make_local_ifunc_plt_entry(Symbol_table*, Layout*,
815 Sized_relobj_file<32, false>* relobj,
816 unsigned int local_sym_index);
818 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
820 define_tls_base_symbol(Symbol_table*, Layout*);
822 // Create a GOT entry for the TLS module index.
824 got_mod_index_entry(Symbol_table* symtab, Layout* layout,
825 Sized_relobj_file<32, false>* object);
827 // Get the PLT section.
828 Output_data_plt_i386*
831 gold_assert(this->plt_ != NULL);
835 // Get the dynamic reloc section, creating it if necessary.
837 rel_dyn_section(Layout*);
839 // Get the section to use for TLS_DESC relocations.
841 rel_tls_desc_section(Layout*) const;
843 // Get the section to use for IRELATIVE relocations.
845 rel_irelative_section(Layout*);
847 // Add a potential copy relocation.
849 copy_reloc(Symbol_table* symtab, Layout* layout,
850 Sized_relobj_file<32, false>* object,
851 unsigned int shndx, Output_section* output_section,
852 Symbol* sym, const elfcpp::Rel<32, false>& reloc)
854 unsigned int r_type = elfcpp::elf_r_type<32>(reloc.get_r_info());
855 this->copy_relocs_.copy_reloc(symtab, layout,
856 symtab->get_sized_symbol<32>(sym),
857 object, shndx, output_section,
858 r_type, reloc.get_r_offset(), 0,
859 this->rel_dyn_section(layout));
862 // Information about this specific target which we pass to the
863 // general Target structure.
864 static const Target::Target_info i386_info;
866 // The types of GOT entries needed for this platform.
867 // These values are exposed to the ABI in an incremental link.
868 // Do not renumber existing values without changing the version
869 // number of the .gnu_incremental_inputs section.
872 GOT_TYPE_STANDARD = 0, // GOT entry for a regular symbol
873 GOT_TYPE_TLS_NOFFSET = 1, // GOT entry for negative TLS offset
874 GOT_TYPE_TLS_OFFSET = 2, // GOT entry for positive TLS offset
875 GOT_TYPE_TLS_PAIR = 3, // GOT entry for TLS module/offset pair
876 GOT_TYPE_TLS_DESC = 4 // GOT entry for TLS_DESC pair
880 Output_data_got<32, false>* got_;
882 Output_data_plt_i386* plt_;
883 // The GOT PLT section.
884 Output_data_got_plt_i386* got_plt_;
885 // The GOT section for IRELATIVE relocations.
886 Output_data_space* got_irelative_;
887 // The GOT section for TLSDESC relocations.
888 Output_data_got<32, false>* got_tlsdesc_;
889 // The _GLOBAL_OFFSET_TABLE_ symbol.
890 Symbol* global_offset_table_;
891 // The dynamic reloc section.
892 Reloc_section* rel_dyn_;
893 // The section to use for IRELATIVE relocs.
894 Reloc_section* rel_irelative_;
895 // Relocs saved to avoid a COPY reloc.
896 Copy_relocs<elfcpp::SHT_REL, 32, false> copy_relocs_;
897 // Offset of the GOT entry for the TLS module index.
898 unsigned int got_mod_index_offset_;
899 // True if the _TLS_MODULE_BASE_ symbol has been defined.
900 bool tls_base_symbol_defined_;
903 const Target::Target_info Target_i386::i386_info =
906 false, // is_big_endian
907 elfcpp::EM_386, // machine_code
908 false, // has_make_symbol
909 false, // has_resolve
910 true, // has_code_fill
911 true, // is_default_stack_executable
912 true, // can_icf_inline_merge_sections
914 "/usr/lib/libc.so.1", // dynamic_linker
915 0x08048000, // default_text_segment_address
916 0x1000, // abi_pagesize (overridable by -z max-page-size)
917 0x1000, // common_pagesize (overridable by -z common-page-size)
918 false, // isolate_execinstr
920 elfcpp::SHN_UNDEF, // small_common_shndx
921 elfcpp::SHN_UNDEF, // large_common_shndx
922 0, // small_common_section_flags
923 0, // large_common_section_flags
924 NULL, // attributes_section
925 NULL, // attributes_vendor
926 "_start", // entry_symbol_name
927 32, // hash_entry_size
930 // Get the GOT section, creating it if necessary.
932 Output_data_got<32, false>*
933 Target_i386::got_section(Symbol_table* symtab, Layout* layout)
935 if (this->got_ == NULL)
937 gold_assert(symtab != NULL && layout != NULL);
939 this->got_ = new Output_data_got<32, false>();
941 // When using -z now, we can treat .got.plt as a relro section.
942 // Without -z now, it is modified after program startup by lazy
944 bool is_got_plt_relro = parameters->options().now();
945 Output_section_order got_order = (is_got_plt_relro
948 Output_section_order got_plt_order = (is_got_plt_relro
950 : ORDER_NON_RELRO_FIRST);
952 layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
954 | elfcpp::SHF_WRITE),
955 this->got_, got_order, true);
957 this->got_plt_ = new Output_data_got_plt_i386(layout);
958 layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
960 | elfcpp::SHF_WRITE),
961 this->got_plt_, got_plt_order,
964 // The first three entries are reserved.
965 this->got_plt_->set_current_data_size(3 * 4);
967 if (!is_got_plt_relro)
969 // Those bytes can go into the relro segment.
970 layout->increase_relro(3 * 4);
973 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
974 this->global_offset_table_ =
975 symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
976 Symbol_table::PREDEFINED,
978 0, 0, elfcpp::STT_OBJECT,
980 elfcpp::STV_HIDDEN, 0,
983 // If there are any IRELATIVE relocations, they get GOT entries
984 // in .got.plt after the jump slot relocations.
985 this->got_irelative_ = new Output_data_space(4, "** GOT IRELATIVE PLT");
986 layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
988 | elfcpp::SHF_WRITE),
989 this->got_irelative_,
990 got_plt_order, is_got_plt_relro);
992 // If there are any TLSDESC relocations, they get GOT entries in
993 // .got.plt after the jump slot entries.
994 this->got_tlsdesc_ = new Output_data_got<32, false>();
995 layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
997 | elfcpp::SHF_WRITE),
999 got_plt_order, is_got_plt_relro);
1005 // Get the dynamic reloc section, creating it if necessary.
1007 Target_i386::Reloc_section*
1008 Target_i386::rel_dyn_section(Layout* layout)
1010 if (this->rel_dyn_ == NULL)
1012 gold_assert(layout != NULL);
1013 this->rel_dyn_ = new Reloc_section(parameters->options().combreloc());
1014 layout->add_output_section_data(".rel.dyn", elfcpp::SHT_REL,
1015 elfcpp::SHF_ALLOC, this->rel_dyn_,
1016 ORDER_DYNAMIC_RELOCS, false);
1018 return this->rel_dyn_;
1021 // Get the section to use for IRELATIVE relocs, creating it if
1022 // necessary. These go in .rel.dyn, but only after all other dynamic
1023 // relocations. They need to follow the other dynamic relocations so
1024 // that they can refer to global variables initialized by those
1027 Target_i386::Reloc_section*
1028 Target_i386::rel_irelative_section(Layout* layout)
1030 if (this->rel_irelative_ == NULL)
1032 // Make sure we have already create the dynamic reloc section.
1033 this->rel_dyn_section(layout);
1034 this->rel_irelative_ = new Reloc_section(false);
1035 layout->add_output_section_data(".rel.dyn", elfcpp::SHT_REL,
1036 elfcpp::SHF_ALLOC, this->rel_irelative_,
1037 ORDER_DYNAMIC_RELOCS, false);
1038 gold_assert(this->rel_dyn_->output_section()
1039 == this->rel_irelative_->output_section());
1041 return this->rel_irelative_;
1044 // Write the first three reserved words of the .got.plt section.
1045 // The remainder of the section is written while writing the PLT
1046 // in Output_data_plt_i386::do_write.
1049 Output_data_got_plt_i386::do_write(Output_file* of)
1051 // The first entry in the GOT is the address of the .dynamic section
1052 // aka the PT_DYNAMIC segment. The next two entries are reserved.
1053 // We saved space for them when we created the section in
1054 // Target_i386::got_section.
1055 const off_t got_file_offset = this->offset();
1056 gold_assert(this->data_size() >= 12);
1057 unsigned char* const got_view = of->get_output_view(got_file_offset, 12);
1058 Output_section* dynamic = this->layout_->dynamic_section();
1059 uint32_t dynamic_addr = dynamic == NULL ? 0 : dynamic->address();
1060 elfcpp::Swap<32, false>::writeval(got_view, dynamic_addr);
1061 memset(got_view + 4, 0, 8);
1062 of->write_output_view(got_file_offset, 12, got_view);
1065 // Create the PLT section. The ordinary .got section is an argument,
1066 // since we need to refer to the start. We also create our own .got
1067 // section just for PLT entries.
1069 Output_data_plt_i386::Output_data_plt_i386(Layout* layout,
1071 Output_data_got_plt_i386* got_plt,
1072 Output_data_space* got_irelative)
1073 : Output_section_data(addralign),
1074 tls_desc_rel_(NULL), irelative_rel_(NULL), got_plt_(got_plt),
1075 got_irelative_(got_irelative), count_(0), irelative_count_(0),
1076 global_ifuncs_(), local_ifuncs_()
1078 this->rel_ = new Reloc_section(false);
1079 layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL,
1080 elfcpp::SHF_ALLOC, this->rel_,
1081 ORDER_DYNAMIC_PLT_RELOCS, false);
1085 Output_data_plt_i386::do_adjust_output_section(Output_section* os)
1087 // UnixWare sets the entsize of .plt to 4, and so does the old GNU
1088 // linker, and so do we.
1092 // Add an entry to the PLT.
1095 Output_data_plt_i386::add_entry(Symbol_table* symtab, Layout* layout,
1098 gold_assert(!gsym->has_plt_offset());
1100 // Every PLT entry needs a reloc.
1101 if (gsym->type() == elfcpp::STT_GNU_IFUNC
1102 && gsym->can_use_relative_reloc(false))
1104 gsym->set_plt_offset(this->irelative_count_ * this->get_plt_entry_size());
1105 ++this->irelative_count_;
1106 section_offset_type got_offset =
1107 this->got_irelative_->current_data_size();
1108 this->got_irelative_->set_current_data_size(got_offset + 4);
1109 Reloc_section* rel = this->rel_irelative(symtab, layout);
1110 rel->add_symbolless_global_addend(gsym, elfcpp::R_386_IRELATIVE,
1111 this->got_irelative_, got_offset);
1112 struct Global_ifunc gi;
1114 gi.got_offset = got_offset;
1115 this->global_ifuncs_.push_back(gi);
1119 // When setting the PLT offset we skip the initial reserved PLT
1121 gsym->set_plt_offset((this->count_ + 1) * this->get_plt_entry_size());
1125 section_offset_type got_offset = this->got_plt_->current_data_size();
1127 // Every PLT entry needs a GOT entry which points back to the
1128 // PLT entry (this will be changed by the dynamic linker,
1129 // normally lazily when the function is called).
1130 this->got_plt_->set_current_data_size(got_offset + 4);
1132 gsym->set_needs_dynsym_entry();
1133 this->rel_->add_global(gsym, elfcpp::R_386_JUMP_SLOT, this->got_plt_,
1137 // Note that we don't need to save the symbol. The contents of the
1138 // PLT are independent of which symbols are used. The symbols only
1139 // appear in the relocations.
1142 // Add an entry to the PLT for a local STT_GNU_IFUNC symbol. Return
1146 Output_data_plt_i386::add_local_ifunc_entry(
1147 Symbol_table* symtab,
1149 Sized_relobj_file<32, false>* relobj,
1150 unsigned int local_sym_index)
1152 unsigned int plt_offset = this->irelative_count_ * this->get_plt_entry_size();
1153 ++this->irelative_count_;
1155 section_offset_type got_offset = this->got_irelative_->current_data_size();
1157 // Every PLT entry needs a GOT entry which points back to the PLT
1159 this->got_irelative_->set_current_data_size(got_offset + 4);
1161 // Every PLT entry needs a reloc.
1162 Reloc_section* rel = this->rel_irelative(symtab, layout);
1163 rel->add_symbolless_local_addend(relobj, local_sym_index,
1164 elfcpp::R_386_IRELATIVE,
1165 this->got_irelative_, got_offset);
1167 struct Local_ifunc li;
1169 li.local_sym_index = local_sym_index;
1170 li.got_offset = got_offset;
1171 this->local_ifuncs_.push_back(li);
1176 // Return where the TLS_DESC relocations should go, creating it if
1177 // necessary. These follow the JUMP_SLOT relocations.
1179 Output_data_plt_i386::Reloc_section*
1180 Output_data_plt_i386::rel_tls_desc(Layout* layout)
1182 if (this->tls_desc_rel_ == NULL)
1184 this->tls_desc_rel_ = new Reloc_section(false);
1185 layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL,
1186 elfcpp::SHF_ALLOC, this->tls_desc_rel_,
1187 ORDER_DYNAMIC_PLT_RELOCS, false);
1188 gold_assert(this->tls_desc_rel_->output_section()
1189 == this->rel_->output_section());
1191 return this->tls_desc_rel_;
1194 // Return where the IRELATIVE relocations should go in the PLT. These
1195 // follow the JUMP_SLOT and TLS_DESC relocations.
1197 Output_data_plt_i386::Reloc_section*
1198 Output_data_plt_i386::rel_irelative(Symbol_table* symtab, Layout* layout)
1200 if (this->irelative_rel_ == NULL)
1202 // Make sure we have a place for the TLS_DESC relocations, in
1203 // case we see any later on.
1204 this->rel_tls_desc(layout);
1205 this->irelative_rel_ = new Reloc_section(false);
1206 layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL,
1207 elfcpp::SHF_ALLOC, this->irelative_rel_,
1208 ORDER_DYNAMIC_PLT_RELOCS, false);
1209 gold_assert(this->irelative_rel_->output_section()
1210 == this->rel_->output_section());
1212 if (parameters->doing_static_link())
1214 // A statically linked executable will only have a .rel.plt
1215 // section to hold R_386_IRELATIVE relocs for STT_GNU_IFUNC
1216 // symbols. The library will use these symbols to locate
1217 // the IRELATIVE relocs at program startup time.
1218 symtab->define_in_output_data("__rel_iplt_start", NULL,
1219 Symbol_table::PREDEFINED,
1220 this->irelative_rel_, 0, 0,
1221 elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL,
1222 elfcpp::STV_HIDDEN, 0, false, true);
1223 symtab->define_in_output_data("__rel_iplt_end", NULL,
1224 Symbol_table::PREDEFINED,
1225 this->irelative_rel_, 0, 0,
1226 elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL,
1227 elfcpp::STV_HIDDEN, 0, true, true);
1230 return this->irelative_rel_;
1233 // Return the PLT address to use for a global symbol.
1236 Output_data_plt_i386::address_for_global(const Symbol* gsym)
1238 uint64_t offset = 0;
1239 if (gsym->type() == elfcpp::STT_GNU_IFUNC
1240 && gsym->can_use_relative_reloc(false))
1241 offset = (this->count_ + 1) * this->get_plt_entry_size();
1242 return this->address() + offset + gsym->plt_offset();
1245 // Return the PLT address to use for a local symbol. These are always
1246 // IRELATIVE relocs.
1249 Output_data_plt_i386::address_for_local(const Relobj* object,
1252 return (this->address()
1253 + (this->count_ + 1) * this->get_plt_entry_size()
1254 + object->local_plt_offset(r_sym));
1257 // The first entry in the PLT for an executable.
1259 const unsigned char Output_data_plt_i386_exec::first_plt_entry[plt_entry_size] =
1261 0xff, 0x35, // pushl contents of memory address
1262 0, 0, 0, 0, // replaced with address of .got + 4
1263 0xff, 0x25, // jmp indirect
1264 0, 0, 0, 0, // replaced with address of .got + 8
1265 0, 0, 0, 0 // unused
1269 Output_data_plt_i386_exec::do_fill_first_plt_entry(
1271 elfcpp::Elf_types<32>::Elf_Addr got_address)
1273 memcpy(pov, first_plt_entry, plt_entry_size);
1274 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_address + 4);
1275 elfcpp::Swap<32, false>::writeval(pov + 8, got_address + 8);
1278 // The first entry in the PLT for a shared object.
1280 const unsigned char Output_data_plt_i386_dyn::first_plt_entry[plt_entry_size] =
1282 0xff, 0xb3, 4, 0, 0, 0, // pushl 4(%ebx)
1283 0xff, 0xa3, 8, 0, 0, 0, // jmp *8(%ebx)
1284 0, 0, 0, 0 // unused
1288 Output_data_plt_i386_dyn::do_fill_first_plt_entry(
1290 elfcpp::Elf_types<32>::Elf_Addr)
1292 memcpy(pov, first_plt_entry, plt_entry_size);
1295 // Subsequent entries in the PLT for an executable.
1297 const unsigned char Output_data_plt_i386_exec::plt_entry[plt_entry_size] =
1299 0xff, 0x25, // jmp indirect
1300 0, 0, 0, 0, // replaced with address of symbol in .got
1301 0x68, // pushl immediate
1302 0, 0, 0, 0, // replaced with offset into relocation table
1303 0xe9, // jmp relative
1304 0, 0, 0, 0 // replaced with offset to start of .plt
1308 Output_data_plt_i386_exec::do_fill_plt_entry(
1310 elfcpp::Elf_types<32>::Elf_Addr got_address,
1311 unsigned int got_offset,
1312 unsigned int plt_offset,
1313 unsigned int plt_rel_offset)
1315 memcpy(pov, plt_entry, plt_entry_size);
1316 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
1317 got_address + 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 // Subsequent entries in the PLT for a shared object.
1325 const unsigned char Output_data_plt_i386_dyn::plt_entry[plt_entry_size] =
1327 0xff, 0xa3, // jmp *offset(%ebx)
1328 0, 0, 0, 0, // replaced with offset of symbol in .got
1329 0x68, // pushl immediate
1330 0, 0, 0, 0, // replaced with offset into relocation table
1331 0xe9, // jmp relative
1332 0, 0, 0, 0 // replaced with offset to start of .plt
1336 Output_data_plt_i386_dyn::do_fill_plt_entry(unsigned char* pov,
1337 elfcpp::Elf_types<32>::Elf_Addr,
1338 unsigned int got_offset,
1339 unsigned int plt_offset,
1340 unsigned int plt_rel_offset)
1342 memcpy(pov, plt_entry, plt_entry_size);
1343 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_offset);
1344 elfcpp::Swap_unaligned<32, false>::writeval(pov + 7, plt_rel_offset);
1345 elfcpp::Swap<32, false>::writeval(pov + 12, - (plt_offset + 12 + 4));
1349 // The .eh_frame unwind information for the PLT.
1352 Output_data_plt_i386::plt_eh_frame_cie[plt_eh_frame_cie_size] =
1355 'z', // Augmentation: augmentation size included.
1356 'R', // Augmentation: FDE encoding included.
1357 '\0', // End of augmentation string.
1358 1, // Code alignment factor.
1359 0x7c, // Data alignment factor.
1360 8, // Return address column.
1361 1, // Augmentation size.
1362 (elfcpp::DW_EH_PE_pcrel // FDE encoding.
1363 | elfcpp::DW_EH_PE_sdata4),
1364 elfcpp::DW_CFA_def_cfa, 4, 4, // DW_CFA_def_cfa: r4 (esp) ofs 4.
1365 elfcpp::DW_CFA_offset + 8, 1, // DW_CFA_offset: r8 (eip) at cfa-4.
1366 elfcpp::DW_CFA_nop, // Align to 16 bytes.
1371 Output_data_plt_i386_standard::plt_eh_frame_fde[plt_eh_frame_fde_size] =
1373 0, 0, 0, 0, // Replaced with offset to .plt.
1374 0, 0, 0, 0, // Replaced with size of .plt.
1375 0, // Augmentation size.
1376 elfcpp::DW_CFA_def_cfa_offset, 8, // DW_CFA_def_cfa_offset: 8.
1377 elfcpp::DW_CFA_advance_loc + 6, // Advance 6 to __PLT__ + 6.
1378 elfcpp::DW_CFA_def_cfa_offset, 12, // DW_CFA_def_cfa_offset: 12.
1379 elfcpp::DW_CFA_advance_loc + 10, // Advance 10 to __PLT__ + 16.
1380 elfcpp::DW_CFA_def_cfa_expression, // DW_CFA_def_cfa_expression.
1381 11, // Block length.
1382 elfcpp::DW_OP_breg4, 4, // Push %esp + 4.
1383 elfcpp::DW_OP_breg8, 0, // Push %eip.
1384 elfcpp::DW_OP_lit15, // Push 0xf.
1385 elfcpp::DW_OP_and, // & (%eip & 0xf).
1386 elfcpp::DW_OP_lit11, // Push 0xb.
1387 elfcpp::DW_OP_ge, // >= ((%eip & 0xf) >= 0xb)
1388 elfcpp::DW_OP_lit2, // Push 2.
1389 elfcpp::DW_OP_shl, // << (((%eip & 0xf) >= 0xb) << 2)
1390 elfcpp::DW_OP_plus, // + ((((%eip&0xf)>=0xb)<<2)+%esp+4
1391 elfcpp::DW_CFA_nop, // Align to 32 bytes.
1397 // Write out the PLT. This uses the hand-coded instructions above,
1398 // and adjusts them as needed. This is all specified by the i386 ELF
1399 // Processor Supplement.
1402 Output_data_plt_i386::do_write(Output_file* of)
1404 const off_t offset = this->offset();
1405 const section_size_type oview_size =
1406 convert_to_section_size_type(this->data_size());
1407 unsigned char* const oview = of->get_output_view(offset, oview_size);
1409 const off_t got_file_offset = this->got_plt_->offset();
1410 gold_assert(parameters->incremental_update()
1411 || (got_file_offset + this->got_plt_->data_size()
1412 == this->got_irelative_->offset()));
1413 const section_size_type got_size =
1414 convert_to_section_size_type(this->got_plt_->data_size()
1415 + this->got_irelative_->data_size());
1417 unsigned char* const got_view = of->get_output_view(got_file_offset,
1420 unsigned char* pov = oview;
1422 elfcpp::Elf_types<32>::Elf_Addr plt_address = this->address();
1423 elfcpp::Elf_types<32>::Elf_Addr got_address = this->got_plt_->address();
1425 this->fill_first_plt_entry(pov, got_address);
1426 pov += this->get_plt_entry_size();
1428 // The first three entries in the GOT are reserved, and are written
1429 // by Output_data_got_plt_i386::do_write.
1430 unsigned char* got_pov = got_view + 12;
1432 const int rel_size = elfcpp::Elf_sizes<32>::rel_size;
1434 unsigned int plt_offset = this->get_plt_entry_size();
1435 unsigned int plt_rel_offset = 0;
1436 unsigned int got_offset = 12;
1437 const unsigned int count = this->count_ + this->irelative_count_;
1438 for (unsigned int i = 0;
1441 pov += this->get_plt_entry_size(),
1443 plt_offset += this->get_plt_entry_size(),
1444 plt_rel_offset += rel_size,
1447 // Set and adjust the PLT entry itself.
1448 unsigned int lazy_offset = this->fill_plt_entry(pov,
1454 // Set the entry in the GOT.
1455 elfcpp::Swap<32, false>::writeval(got_pov,
1456 plt_address + plt_offset + lazy_offset);
1459 // If any STT_GNU_IFUNC symbols have PLT entries, we need to change
1460 // the GOT to point to the actual symbol value, rather than point to
1461 // the PLT entry. That will let the dynamic linker call the right
1462 // function when resolving IRELATIVE relocations.
1463 unsigned char* got_irelative_view = got_view + this->got_plt_->data_size();
1464 for (std::vector<Global_ifunc>::const_iterator p =
1465 this->global_ifuncs_.begin();
1466 p != this->global_ifuncs_.end();
1469 const Sized_symbol<32>* ssym =
1470 static_cast<const Sized_symbol<32>*>(p->sym);
1471 elfcpp::Swap<32, false>::writeval(got_irelative_view + p->got_offset,
1475 for (std::vector<Local_ifunc>::const_iterator p =
1476 this->local_ifuncs_.begin();
1477 p != this->local_ifuncs_.end();
1480 const Symbol_value<32>* psymval =
1481 p->object->local_symbol(p->local_sym_index);
1482 elfcpp::Swap<32, false>::writeval(got_irelative_view + p->got_offset,
1483 psymval->value(p->object, 0));
1486 gold_assert(static_cast<section_size_type>(pov - oview) == oview_size);
1487 gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size);
1489 of->write_output_view(offset, oview_size, oview);
1490 of->write_output_view(got_file_offset, got_size, got_view);
1493 // Create the PLT section.
1496 Target_i386::make_plt_section(Symbol_table* symtab, Layout* layout)
1498 if (this->plt_ == NULL)
1500 // Create the GOT sections first.
1501 this->got_section(symtab, layout);
1503 const bool dyn = parameters->options().output_is_position_independent();
1504 this->plt_ = this->make_data_plt(layout,
1506 this->got_irelative_,
1509 // Add unwind information if requested.
1510 if (parameters->options().ld_generated_unwind_info())
1511 this->plt_->add_eh_frame(layout);
1513 layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
1515 | elfcpp::SHF_EXECINSTR),
1516 this->plt_, ORDER_PLT, false);
1518 // Make the sh_info field of .rel.plt point to .plt.
1519 Output_section* rel_plt_os = this->plt_->rel_plt()->output_section();
1520 rel_plt_os->set_info_section(this->plt_->output_section());
1524 // Create a PLT entry for a global symbol.
1527 Target_i386::make_plt_entry(Symbol_table* symtab, Layout* layout, Symbol* gsym)
1529 if (gsym->has_plt_offset())
1531 if (this->plt_ == NULL)
1532 this->make_plt_section(symtab, layout);
1533 this->plt_->add_entry(symtab, layout, gsym);
1536 // Make a PLT entry for a local STT_GNU_IFUNC symbol.
1539 Target_i386::make_local_ifunc_plt_entry(Symbol_table* symtab, Layout* layout,
1540 Sized_relobj_file<32, false>* relobj,
1541 unsigned int local_sym_index)
1543 if (relobj->local_has_plt_offset(local_sym_index))
1545 if (this->plt_ == NULL)
1546 this->make_plt_section(symtab, layout);
1547 unsigned int plt_offset = this->plt_->add_local_ifunc_entry(symtab, layout,
1550 relobj->set_local_plt_offset(local_sym_index, plt_offset);
1553 // Return the number of entries in the PLT.
1556 Target_i386::plt_entry_count() const
1558 if (this->plt_ == NULL)
1560 return this->plt_->entry_count();
1563 // Return the offset of the first non-reserved PLT entry.
1566 Target_i386::first_plt_entry_offset() const
1568 if (this->plt_ == NULL)
1570 return this->plt_->first_plt_entry_offset();
1573 // Return the size of each PLT entry.
1576 Target_i386::plt_entry_size() const
1578 if (this->plt_ == NULL)
1580 return this->plt_->get_plt_entry_size();
1583 // Get the section to use for TLS_DESC relocations.
1585 Target_i386::Reloc_section*
1586 Target_i386::rel_tls_desc_section(Layout* layout) const
1588 return this->plt_section()->rel_tls_desc(layout);
1591 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
1594 Target_i386::define_tls_base_symbol(Symbol_table* symtab, Layout* layout)
1596 if (this->tls_base_symbol_defined_)
1599 Output_segment* tls_segment = layout->tls_segment();
1600 if (tls_segment != NULL)
1602 bool is_exec = parameters->options().output_is_executable();
1603 symtab->define_in_output_segment("_TLS_MODULE_BASE_", NULL,
1604 Symbol_table::PREDEFINED,
1608 elfcpp::STV_HIDDEN, 0,
1610 ? Symbol::SEGMENT_END
1611 : Symbol::SEGMENT_START),
1614 this->tls_base_symbol_defined_ = true;
1617 // Create a GOT entry for the TLS module index.
1620 Target_i386::got_mod_index_entry(Symbol_table* symtab, Layout* layout,
1621 Sized_relobj_file<32, false>* object)
1623 if (this->got_mod_index_offset_ == -1U)
1625 gold_assert(symtab != NULL && layout != NULL && object != NULL);
1626 Reloc_section* rel_dyn = this->rel_dyn_section(layout);
1627 Output_data_got<32, false>* got = this->got_section(symtab, layout);
1628 unsigned int got_offset = got->add_constant(0);
1629 rel_dyn->add_local(object, 0, elfcpp::R_386_TLS_DTPMOD32, got,
1631 got->add_constant(0);
1632 this->got_mod_index_offset_ = got_offset;
1634 return this->got_mod_index_offset_;
1637 // Optimize the TLS relocation type based on what we know about the
1638 // symbol. IS_FINAL is true if the final address of this symbol is
1639 // known at link time.
1641 tls::Tls_optimization
1642 Target_i386::optimize_tls_reloc(bool is_final, int r_type)
1644 // If we are generating a shared library, then we can't do anything
1646 if (parameters->options().shared())
1647 return tls::TLSOPT_NONE;
1651 case elfcpp::R_386_TLS_GD:
1652 case elfcpp::R_386_TLS_GOTDESC:
1653 case elfcpp::R_386_TLS_DESC_CALL:
1654 // These are General-Dynamic which permits fully general TLS
1655 // access. Since we know that we are generating an executable,
1656 // we can convert this to Initial-Exec. If we also know that
1657 // this is a local symbol, we can further switch to Local-Exec.
1659 return tls::TLSOPT_TO_LE;
1660 return tls::TLSOPT_TO_IE;
1662 case elfcpp::R_386_TLS_LDM:
1663 // This is Local-Dynamic, which refers to a local symbol in the
1664 // dynamic TLS block. Since we know that we generating an
1665 // executable, we can switch to Local-Exec.
1666 return tls::TLSOPT_TO_LE;
1668 case elfcpp::R_386_TLS_LDO_32:
1669 // Another type of Local-Dynamic relocation.
1670 return tls::TLSOPT_TO_LE;
1672 case elfcpp::R_386_TLS_IE:
1673 case elfcpp::R_386_TLS_GOTIE:
1674 case elfcpp::R_386_TLS_IE_32:
1675 // These are Initial-Exec relocs which get the thread offset
1676 // from the GOT. If we know that we are linking against the
1677 // local symbol, we can switch to Local-Exec, which links the
1678 // thread offset into the instruction.
1680 return tls::TLSOPT_TO_LE;
1681 return tls::TLSOPT_NONE;
1683 case elfcpp::R_386_TLS_LE:
1684 case elfcpp::R_386_TLS_LE_32:
1685 // When we already have Local-Exec, there is nothing further we
1687 return tls::TLSOPT_NONE;
1694 // Get the Reference_flags for a particular relocation.
1697 Target_i386::Scan::get_reference_flags(unsigned int r_type)
1701 case elfcpp::R_386_NONE:
1702 case elfcpp::R_386_GNU_VTINHERIT:
1703 case elfcpp::R_386_GNU_VTENTRY:
1704 case elfcpp::R_386_GOTPC:
1705 // No symbol reference.
1708 case elfcpp::R_386_32:
1709 case elfcpp::R_386_16:
1710 case elfcpp::R_386_8:
1711 return Symbol::ABSOLUTE_REF;
1713 case elfcpp::R_386_PC32:
1714 case elfcpp::R_386_PC16:
1715 case elfcpp::R_386_PC8:
1716 case elfcpp::R_386_GOTOFF:
1717 return Symbol::RELATIVE_REF;
1719 case elfcpp::R_386_PLT32:
1720 return Symbol::FUNCTION_CALL | Symbol::RELATIVE_REF;
1722 case elfcpp::R_386_GOT32:
1723 case elfcpp::R_386_GOT32X:
1725 return Symbol::ABSOLUTE_REF;
1727 case elfcpp::R_386_TLS_GD: // Global-dynamic
1728 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url)
1729 case elfcpp::R_386_TLS_DESC_CALL:
1730 case elfcpp::R_386_TLS_LDM: // Local-dynamic
1731 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
1732 case elfcpp::R_386_TLS_IE: // Initial-exec
1733 case elfcpp::R_386_TLS_IE_32:
1734 case elfcpp::R_386_TLS_GOTIE:
1735 case elfcpp::R_386_TLS_LE: // Local-exec
1736 case elfcpp::R_386_TLS_LE_32:
1737 return Symbol::TLS_REF;
1739 case elfcpp::R_386_COPY:
1740 case elfcpp::R_386_GLOB_DAT:
1741 case elfcpp::R_386_JUMP_SLOT:
1742 case elfcpp::R_386_RELATIVE:
1743 case elfcpp::R_386_IRELATIVE:
1744 case elfcpp::R_386_TLS_TPOFF:
1745 case elfcpp::R_386_TLS_DTPMOD32:
1746 case elfcpp::R_386_TLS_DTPOFF32:
1747 case elfcpp::R_386_TLS_TPOFF32:
1748 case elfcpp::R_386_TLS_DESC:
1749 case elfcpp::R_386_32PLT:
1750 case elfcpp::R_386_TLS_GD_32:
1751 case elfcpp::R_386_TLS_GD_PUSH:
1752 case elfcpp::R_386_TLS_GD_CALL:
1753 case elfcpp::R_386_TLS_GD_POP:
1754 case elfcpp::R_386_TLS_LDM_32:
1755 case elfcpp::R_386_TLS_LDM_PUSH:
1756 case elfcpp::R_386_TLS_LDM_CALL:
1757 case elfcpp::R_386_TLS_LDM_POP:
1758 case elfcpp::R_386_USED_BY_INTEL_200:
1760 // Not expected. We will give an error later.
1765 // Report an unsupported relocation against a local symbol.
1768 Target_i386::Scan::unsupported_reloc_local(Sized_relobj_file<32, false>* object,
1769 unsigned int r_type)
1771 gold_error(_("%s: unsupported reloc %u against local symbol"),
1772 object->name().c_str(), r_type);
1775 // Return whether we need to make a PLT entry for a relocation of a
1776 // given type against a STT_GNU_IFUNC symbol.
1779 Target_i386::Scan::reloc_needs_plt_for_ifunc(
1780 Sized_relobj_file<32, false>* object,
1781 unsigned int r_type)
1783 int flags = Scan::get_reference_flags(r_type);
1784 if (flags & Symbol::TLS_REF)
1785 gold_error(_("%s: unsupported TLS reloc %u for IFUNC symbol"),
1786 object->name().c_str(), r_type);
1790 // Scan a relocation for a local symbol.
1793 Target_i386::Scan::local(Symbol_table* symtab,
1795 Target_i386* target,
1796 Sized_relobj_file<32, false>* object,
1797 unsigned int data_shndx,
1798 Output_section* output_section,
1799 const elfcpp::Rel<32, false>& reloc,
1800 unsigned int r_type,
1801 const elfcpp::Sym<32, false>& lsym,
1807 // A local STT_GNU_IFUNC symbol may require a PLT entry.
1808 if (lsym.get_st_type() == elfcpp::STT_GNU_IFUNC
1809 && this->reloc_needs_plt_for_ifunc(object, r_type))
1811 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1812 target->make_local_ifunc_plt_entry(symtab, layout, object, r_sym);
1817 case elfcpp::R_386_NONE:
1818 case elfcpp::R_386_GNU_VTINHERIT:
1819 case elfcpp::R_386_GNU_VTENTRY:
1822 case elfcpp::R_386_32:
1823 // If building a shared library (or a position-independent
1824 // executable), we need to create a dynamic relocation for
1825 // this location. The relocation applied at link time will
1826 // apply the link-time value, so we flag the location with
1827 // an R_386_RELATIVE relocation so the dynamic loader can
1828 // relocate it easily.
1829 if (parameters->options().output_is_position_independent())
1831 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1832 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1833 rel_dyn->add_local_relative(object, r_sym, elfcpp::R_386_RELATIVE,
1834 output_section, data_shndx,
1835 reloc.get_r_offset());
1839 case elfcpp::R_386_16:
1840 case elfcpp::R_386_8:
1841 // If building a shared library (or a position-independent
1842 // executable), we need to create a dynamic relocation for
1843 // this location. Because the addend needs to remain in the
1844 // data section, we need to be careful not to apply this
1845 // relocation statically.
1846 if (parameters->options().output_is_position_independent())
1848 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1849 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1850 if (lsym.get_st_type() != elfcpp::STT_SECTION)
1851 rel_dyn->add_local(object, r_sym, r_type, output_section,
1852 data_shndx, reloc.get_r_offset());
1855 gold_assert(lsym.get_st_value() == 0);
1856 unsigned int shndx = lsym.get_st_shndx();
1858 shndx = object->adjust_sym_shndx(r_sym, shndx,
1861 object->error(_("section symbol %u has bad shndx %u"),
1864 rel_dyn->add_local_section(object, shndx,
1865 r_type, output_section,
1866 data_shndx, reloc.get_r_offset());
1871 case elfcpp::R_386_PC32:
1872 case elfcpp::R_386_PC16:
1873 case elfcpp::R_386_PC8:
1876 case elfcpp::R_386_PLT32:
1877 // Since we know this is a local symbol, we can handle this as a
1881 case elfcpp::R_386_GOTOFF:
1882 case elfcpp::R_386_GOTPC:
1883 // We need a GOT section.
1884 target->got_section(symtab, layout);
1887 case elfcpp::R_386_GOT32:
1888 case elfcpp::R_386_GOT32X:
1890 // We need GOT section.
1891 Output_data_got<32, false>* got = target->got_section(symtab, layout);
1893 // If the relocation symbol isn't IFUNC,
1894 // and is local, then we will convert
1895 // mov foo@GOT(%reg), %reg
1897 // lea foo@GOTOFF(%reg), %reg
1898 // in Relocate::relocate.
1899 if (reloc.get_r_offset() >= 2
1900 && lsym.get_st_type() != elfcpp::STT_GNU_IFUNC)
1902 section_size_type stype;
1903 const unsigned char* view = object->section_contents(data_shndx,
1905 if (view[reloc.get_r_offset() - 2] == 0x8b)
1909 // Otherwise, the symbol requires a GOT entry.
1910 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1912 // For a STT_GNU_IFUNC symbol we want the PLT offset. That
1913 // lets function pointers compare correctly with shared
1914 // libraries. Otherwise we would need an IRELATIVE reloc.
1916 if (lsym.get_st_type() == elfcpp::STT_GNU_IFUNC)
1917 is_new = got->add_local_plt(object, r_sym, GOT_TYPE_STANDARD);
1919 is_new = got->add_local(object, r_sym, GOT_TYPE_STANDARD);
1922 // If we are generating a shared object, we need to add a
1923 // dynamic RELATIVE relocation for this symbol's GOT entry.
1924 if (parameters->options().output_is_position_independent())
1926 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1927 unsigned int got_offset =
1928 object->local_got_offset(r_sym, GOT_TYPE_STANDARD);
1929 rel_dyn->add_local_relative(object, r_sym,
1930 elfcpp::R_386_RELATIVE,
1937 // These are relocations which should only be seen by the
1938 // dynamic linker, and should never be seen here.
1939 case elfcpp::R_386_COPY:
1940 case elfcpp::R_386_GLOB_DAT:
1941 case elfcpp::R_386_JUMP_SLOT:
1942 case elfcpp::R_386_RELATIVE:
1943 case elfcpp::R_386_IRELATIVE:
1944 case elfcpp::R_386_TLS_TPOFF:
1945 case elfcpp::R_386_TLS_DTPMOD32:
1946 case elfcpp::R_386_TLS_DTPOFF32:
1947 case elfcpp::R_386_TLS_TPOFF32:
1948 case elfcpp::R_386_TLS_DESC:
1949 gold_error(_("%s: unexpected reloc %u in object file"),
1950 object->name().c_str(), r_type);
1953 // These are initial TLS relocs, which are expected when
1955 case elfcpp::R_386_TLS_GD: // Global-dynamic
1956 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url)
1957 case elfcpp::R_386_TLS_DESC_CALL:
1958 case elfcpp::R_386_TLS_LDM: // Local-dynamic
1959 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
1960 case elfcpp::R_386_TLS_IE: // Initial-exec
1961 case elfcpp::R_386_TLS_IE_32:
1962 case elfcpp::R_386_TLS_GOTIE:
1963 case elfcpp::R_386_TLS_LE: // Local-exec
1964 case elfcpp::R_386_TLS_LE_32:
1966 bool output_is_shared = parameters->options().shared();
1967 const tls::Tls_optimization optimized_type
1968 = Target_i386::optimize_tls_reloc(!output_is_shared, r_type);
1971 case elfcpp::R_386_TLS_GD: // Global-dynamic
1972 if (optimized_type == tls::TLSOPT_NONE)
1974 // Create a pair of GOT entries for the module index and
1975 // dtv-relative offset.
1976 Output_data_got<32, false>* got
1977 = target->got_section(symtab, layout);
1978 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1979 unsigned int shndx = lsym.get_st_shndx();
1981 shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
1983 object->error(_("local symbol %u has bad shndx %u"),
1986 got->add_local_pair_with_rel(object, r_sym, shndx,
1988 target->rel_dyn_section(layout),
1989 elfcpp::R_386_TLS_DTPMOD32);
1991 else if (optimized_type != tls::TLSOPT_TO_LE)
1992 unsupported_reloc_local(object, r_type);
1995 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva)
1996 target->define_tls_base_symbol(symtab, layout);
1997 if (optimized_type == tls::TLSOPT_NONE)
1999 // Create a double GOT entry with an R_386_TLS_DESC
2000 // reloc. The R_386_TLS_DESC reloc is resolved
2001 // lazily, so the GOT entry needs to be in an area in
2002 // .got.plt, not .got. Call got_section to make sure
2003 // the section has been created.
2004 target->got_section(symtab, layout);
2005 Output_data_got<32, false>* got = target->got_tlsdesc_section();
2006 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
2007 if (!object->local_has_got_offset(r_sym, GOT_TYPE_TLS_DESC))
2009 unsigned int got_offset = got->add_constant(0);
2010 // The local symbol value is stored in the second
2012 got->add_local(object, r_sym, GOT_TYPE_TLS_DESC);
2013 // That set the GOT offset of the local symbol to
2014 // point to the second entry, but we want it to
2015 // point to the first.
2016 object->set_local_got_offset(r_sym, GOT_TYPE_TLS_DESC,
2018 Reloc_section* rt = target->rel_tls_desc_section(layout);
2019 rt->add_absolute(elfcpp::R_386_TLS_DESC, got, got_offset);
2022 else if (optimized_type != tls::TLSOPT_TO_LE)
2023 unsupported_reloc_local(object, r_type);
2026 case elfcpp::R_386_TLS_DESC_CALL:
2029 case elfcpp::R_386_TLS_LDM: // Local-dynamic
2030 if (optimized_type == tls::TLSOPT_NONE)
2032 // Create a GOT entry for the module index.
2033 target->got_mod_index_entry(symtab, layout, object);
2035 else if (optimized_type != tls::TLSOPT_TO_LE)
2036 unsupported_reloc_local(object, r_type);
2039 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
2042 case elfcpp::R_386_TLS_IE: // Initial-exec
2043 case elfcpp::R_386_TLS_IE_32:
2044 case elfcpp::R_386_TLS_GOTIE:
2045 layout->set_has_static_tls();
2046 if (optimized_type == tls::TLSOPT_NONE)
2048 // For the R_386_TLS_IE relocation, we need to create a
2049 // dynamic relocation when building a shared library.
2050 if (r_type == elfcpp::R_386_TLS_IE
2051 && parameters->options().shared())
2053 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
2055 = elfcpp::elf_r_sym<32>(reloc.get_r_info());
2056 rel_dyn->add_local_relative(object, r_sym,
2057 elfcpp::R_386_RELATIVE,
2058 output_section, data_shndx,
2059 reloc.get_r_offset());
2061 // Create a GOT entry for the tp-relative offset.
2062 Output_data_got<32, false>* got
2063 = target->got_section(symtab, layout);
2064 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
2065 unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_IE_32
2066 ? elfcpp::R_386_TLS_TPOFF32
2067 : elfcpp::R_386_TLS_TPOFF);
2068 unsigned int got_type = (r_type == elfcpp::R_386_TLS_IE_32
2069 ? GOT_TYPE_TLS_OFFSET
2070 : GOT_TYPE_TLS_NOFFSET);
2071 got->add_local_with_rel(object, r_sym, got_type,
2072 target->rel_dyn_section(layout),
2075 else if (optimized_type != tls::TLSOPT_TO_LE)
2076 unsupported_reloc_local(object, r_type);
2079 case elfcpp::R_386_TLS_LE: // Local-exec
2080 case elfcpp::R_386_TLS_LE_32:
2081 layout->set_has_static_tls();
2082 if (output_is_shared)
2084 // We need to create a dynamic relocation.
2085 gold_assert(lsym.get_st_type() != elfcpp::STT_SECTION);
2086 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
2087 unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_LE_32
2088 ? elfcpp::R_386_TLS_TPOFF32
2089 : elfcpp::R_386_TLS_TPOFF);
2090 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
2091 rel_dyn->add_local(object, r_sym, dyn_r_type, output_section,
2092 data_shndx, reloc.get_r_offset());
2102 case elfcpp::R_386_32PLT:
2103 case elfcpp::R_386_TLS_GD_32:
2104 case elfcpp::R_386_TLS_GD_PUSH:
2105 case elfcpp::R_386_TLS_GD_CALL:
2106 case elfcpp::R_386_TLS_GD_POP:
2107 case elfcpp::R_386_TLS_LDM_32:
2108 case elfcpp::R_386_TLS_LDM_PUSH:
2109 case elfcpp::R_386_TLS_LDM_CALL:
2110 case elfcpp::R_386_TLS_LDM_POP:
2111 case elfcpp::R_386_USED_BY_INTEL_200:
2113 unsupported_reloc_local(object, r_type);
2118 // Report an unsupported relocation against a global symbol.
2121 Target_i386::Scan::unsupported_reloc_global(
2122 Sized_relobj_file<32, false>* object,
2123 unsigned int r_type,
2126 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
2127 object->name().c_str(), r_type, gsym->demangled_name().c_str());
2131 Target_i386::Scan::possible_function_pointer_reloc(unsigned int r_type)
2135 case elfcpp::R_386_32:
2136 case elfcpp::R_386_16:
2137 case elfcpp::R_386_8:
2138 case elfcpp::R_386_GOTOFF:
2139 case elfcpp::R_386_GOT32:
2140 case elfcpp::R_386_GOT32X:
2151 Target_i386::Scan::local_reloc_may_be_function_pointer(
2155 Sized_relobj_file<32, false>* ,
2158 const elfcpp::Rel<32, false>& ,
2159 unsigned int r_type,
2160 const elfcpp::Sym<32, false>&)
2162 return possible_function_pointer_reloc(r_type);
2166 Target_i386::Scan::global_reloc_may_be_function_pointer(
2170 Sized_relobj_file<32, false>* ,
2173 const elfcpp::Rel<32, false>& ,
2174 unsigned int r_type,
2177 return possible_function_pointer_reloc(r_type);
2180 // Scan a relocation for a global symbol.
2183 Target_i386::Scan::global(Symbol_table* symtab,
2185 Target_i386* target,
2186 Sized_relobj_file<32, false>* object,
2187 unsigned int data_shndx,
2188 Output_section* output_section,
2189 const elfcpp::Rel<32, false>& reloc,
2190 unsigned int r_type,
2193 // A STT_GNU_IFUNC symbol may require a PLT entry.
2194 if (gsym->type() == elfcpp::STT_GNU_IFUNC
2195 && this->reloc_needs_plt_for_ifunc(object, r_type))
2196 target->make_plt_entry(symtab, layout, gsym);
2200 case elfcpp::R_386_NONE:
2201 case elfcpp::R_386_GNU_VTINHERIT:
2202 case elfcpp::R_386_GNU_VTENTRY:
2205 case elfcpp::R_386_32:
2206 case elfcpp::R_386_16:
2207 case elfcpp::R_386_8:
2209 // Make a PLT entry if necessary.
2210 if (gsym->needs_plt_entry())
2212 target->make_plt_entry(symtab, layout, gsym);
2213 // Since this is not a PC-relative relocation, we may be
2214 // taking the address of a function. In that case we need to
2215 // set the entry in the dynamic symbol table to the address of
2217 if (gsym->is_from_dynobj() && !parameters->options().shared())
2218 gsym->set_needs_dynsym_value();
2220 // Make a dynamic relocation if necessary.
2221 if (gsym->needs_dynamic_reloc(Scan::get_reference_flags(r_type)))
2223 if (!parameters->options().output_is_position_independent()
2224 && gsym->may_need_copy_reloc())
2226 target->copy_reloc(symtab, layout, object,
2227 data_shndx, output_section, gsym, reloc);
2229 else if (r_type == elfcpp::R_386_32
2230 && gsym->type() == elfcpp::STT_GNU_IFUNC
2231 && gsym->can_use_relative_reloc(false)
2232 && !gsym->is_from_dynobj()
2233 && !gsym->is_undefined()
2234 && !gsym->is_preemptible())
2236 // Use an IRELATIVE reloc for a locally defined
2237 // STT_GNU_IFUNC symbol. This makes a function
2238 // address in a PIE executable match the address in a
2239 // shared library that it links against.
2240 Reloc_section* rel_dyn = target->rel_irelative_section(layout);
2241 rel_dyn->add_symbolless_global_addend(gsym,
2242 elfcpp::R_386_IRELATIVE,
2245 reloc.get_r_offset());
2247 else if (r_type == elfcpp::R_386_32
2248 && gsym->can_use_relative_reloc(false))
2250 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
2251 rel_dyn->add_global_relative(gsym, elfcpp::R_386_RELATIVE,
2252 output_section, object,
2253 data_shndx, reloc.get_r_offset());
2257 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
2258 rel_dyn->add_global(gsym, r_type, output_section, object,
2259 data_shndx, reloc.get_r_offset());
2265 case elfcpp::R_386_PC32:
2266 case elfcpp::R_386_PC16:
2267 case elfcpp::R_386_PC8:
2269 // Make a PLT entry if necessary.
2270 if (gsym->needs_plt_entry())
2272 // These relocations are used for function calls only in
2273 // non-PIC code. For a 32-bit relocation in a shared library,
2274 // we'll need a text relocation anyway, so we can skip the
2275 // PLT entry and let the dynamic linker bind the call directly
2276 // to the target. For smaller relocations, we should use a
2277 // PLT entry to ensure that the call can reach.
2278 if (!parameters->options().shared()
2279 || r_type != elfcpp::R_386_PC32)
2280 target->make_plt_entry(symtab, layout, gsym);
2282 // Make a dynamic relocation if necessary.
2283 if (gsym->needs_dynamic_reloc(Scan::get_reference_flags(r_type)))
2285 if (parameters->options().output_is_executable()
2286 && gsym->may_need_copy_reloc())
2288 target->copy_reloc(symtab, layout, object,
2289 data_shndx, output_section, gsym, reloc);
2293 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
2294 rel_dyn->add_global(gsym, r_type, output_section, object,
2295 data_shndx, reloc.get_r_offset());
2301 case elfcpp::R_386_GOT32:
2302 case elfcpp::R_386_GOT32X:
2304 // The symbol requires a GOT section.
2305 Output_data_got<32, false>* got = target->got_section(symtab, layout);
2307 // If we convert this from
2308 // mov foo@GOT(%reg), %reg
2310 // lea foo@GOTOFF(%reg), %reg
2311 // in Relocate::relocate, then there is nothing to do here.
2312 if (reloc.get_r_offset() >= 2
2313 && Target_i386::can_convert_mov_to_lea(gsym))
2315 section_size_type stype;
2316 const unsigned char* view = object->section_contents(data_shndx,
2318 if (view[reloc.get_r_offset() - 2] == 0x8b)
2322 if (gsym->final_value_is_known())
2324 // For a STT_GNU_IFUNC symbol we want the PLT address.
2325 if (gsym->type() == elfcpp::STT_GNU_IFUNC)
2326 got->add_global_plt(gsym, GOT_TYPE_STANDARD);
2328 got->add_global(gsym, GOT_TYPE_STANDARD);
2332 // If this symbol is not fully resolved, we need to add a
2333 // GOT entry with a dynamic relocation.
2334 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
2336 // Use a GLOB_DAT rather than a RELATIVE reloc if:
2338 // 1) The symbol may be defined in some other module.
2340 // 2) We are building a shared library and this is a
2341 // protected symbol; using GLOB_DAT means that the dynamic
2342 // linker can use the address of the PLT in the main
2343 // executable when appropriate so that function address
2344 // comparisons work.
2346 // 3) This is a STT_GNU_IFUNC symbol in position dependent
2347 // code, again so that function address comparisons work.
2348 if (gsym->is_from_dynobj()
2349 || gsym->is_undefined()
2350 || gsym->is_preemptible()
2351 || (gsym->visibility() == elfcpp::STV_PROTECTED
2352 && parameters->options().shared())
2353 || (gsym->type() == elfcpp::STT_GNU_IFUNC
2354 && parameters->options().output_is_position_independent()))
2355 got->add_global_with_rel(gsym, GOT_TYPE_STANDARD,
2356 rel_dyn, elfcpp::R_386_GLOB_DAT);
2359 // For a STT_GNU_IFUNC symbol we want to write the PLT
2360 // offset into the GOT, so that function pointer
2361 // comparisons work correctly.
2363 if (gsym->type() != elfcpp::STT_GNU_IFUNC)
2364 is_new = got->add_global(gsym, GOT_TYPE_STANDARD);
2367 is_new = got->add_global_plt(gsym, GOT_TYPE_STANDARD);
2368 // Tell the dynamic linker to use the PLT address
2369 // when resolving relocations.
2370 if (gsym->is_from_dynobj()
2371 && !parameters->options().shared())
2372 gsym->set_needs_dynsym_value();
2376 unsigned int got_off = gsym->got_offset(GOT_TYPE_STANDARD);
2377 rel_dyn->add_global_relative(gsym, elfcpp::R_386_RELATIVE,
2385 case elfcpp::R_386_PLT32:
2386 // If the symbol is fully resolved, this is just a PC32 reloc.
2387 // Otherwise we need a PLT entry.
2388 if (gsym->final_value_is_known())
2390 // If building a shared library, we can also skip the PLT entry
2391 // if the symbol is defined in the output file and is protected
2393 if (gsym->is_defined()
2394 && !gsym->is_from_dynobj()
2395 && !gsym->is_preemptible())
2397 target->make_plt_entry(symtab, layout, gsym);
2400 case elfcpp::R_386_GOTOFF:
2401 // A GOT-relative reference must resolve locally.
2402 if (!gsym->is_defined())
2403 gold_error(_("%s: relocation R_386_GOTOFF against undefined symbol %s"
2404 " cannot be used when making a shared object"),
2405 object->name().c_str(), gsym->name());
2406 else if (gsym->is_from_dynobj())
2407 gold_error(_("%s: relocation R_386_GOTOFF against external symbol %s"
2408 " cannot be used when making a shared object"),
2409 object->name().c_str(), gsym->name());
2410 else if (gsym->is_preemptible())
2411 gold_error(_("%s: relocation R_386_GOTOFF against preemptible symbol %s"
2412 " cannot be used when making a shared object"),
2413 object->name().c_str(), gsym->name());
2414 // We need a GOT section.
2415 target->got_section(symtab, layout);
2418 case elfcpp::R_386_GOTPC:
2419 // We need a GOT section.
2420 target->got_section(symtab, layout);
2423 // These are relocations which should only be seen by the
2424 // dynamic linker, and should never be seen here.
2425 case elfcpp::R_386_COPY:
2426 case elfcpp::R_386_GLOB_DAT:
2427 case elfcpp::R_386_JUMP_SLOT:
2428 case elfcpp::R_386_RELATIVE:
2429 case elfcpp::R_386_IRELATIVE:
2430 case elfcpp::R_386_TLS_TPOFF:
2431 case elfcpp::R_386_TLS_DTPMOD32:
2432 case elfcpp::R_386_TLS_DTPOFF32:
2433 case elfcpp::R_386_TLS_TPOFF32:
2434 case elfcpp::R_386_TLS_DESC:
2435 gold_error(_("%s: unexpected reloc %u in object file"),
2436 object->name().c_str(), r_type);
2439 // These are initial tls relocs, which are expected when
2441 case elfcpp::R_386_TLS_GD: // Global-dynamic
2442 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url)
2443 case elfcpp::R_386_TLS_DESC_CALL:
2444 case elfcpp::R_386_TLS_LDM: // Local-dynamic
2445 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
2446 case elfcpp::R_386_TLS_IE: // Initial-exec
2447 case elfcpp::R_386_TLS_IE_32:
2448 case elfcpp::R_386_TLS_GOTIE:
2449 case elfcpp::R_386_TLS_LE: // Local-exec
2450 case elfcpp::R_386_TLS_LE_32:
2452 const bool is_final = gsym->final_value_is_known();
2453 const tls::Tls_optimization optimized_type
2454 = Target_i386::optimize_tls_reloc(is_final, r_type);
2457 case elfcpp::R_386_TLS_GD: // Global-dynamic
2458 if (optimized_type == tls::TLSOPT_NONE)
2460 // Create a pair of GOT entries for the module index and
2461 // dtv-relative offset.
2462 Output_data_got<32, false>* got
2463 = target->got_section(symtab, layout);
2464 got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_PAIR,
2465 target->rel_dyn_section(layout),
2466 elfcpp::R_386_TLS_DTPMOD32,
2467 elfcpp::R_386_TLS_DTPOFF32);
2469 else if (optimized_type == tls::TLSOPT_TO_IE)
2471 // Create a GOT entry for the tp-relative offset.
2472 Output_data_got<32, false>* got
2473 = target->got_section(symtab, layout);
2474 got->add_global_with_rel(gsym, GOT_TYPE_TLS_NOFFSET,
2475 target->rel_dyn_section(layout),
2476 elfcpp::R_386_TLS_TPOFF);
2478 else if (optimized_type != tls::TLSOPT_TO_LE)
2479 unsupported_reloc_global(object, r_type, gsym);
2482 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (~oliva url)
2483 target->define_tls_base_symbol(symtab, layout);
2484 if (optimized_type == tls::TLSOPT_NONE)
2486 // Create a double GOT entry with an R_386_TLS_DESC
2487 // reloc. The R_386_TLS_DESC reloc is resolved
2488 // lazily, so the GOT entry needs to be in an area in
2489 // .got.plt, not .got. Call got_section to make sure
2490 // the section has been created.
2491 target->got_section(symtab, layout);
2492 Output_data_got<32, false>* got = target->got_tlsdesc_section();
2493 Reloc_section* rt = target->rel_tls_desc_section(layout);
2494 got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_DESC, rt,
2495 elfcpp::R_386_TLS_DESC, 0);
2497 else if (optimized_type == tls::TLSOPT_TO_IE)
2499 // Create a GOT entry for the tp-relative offset.
2500 Output_data_got<32, false>* got
2501 = target->got_section(symtab, layout);
2502 got->add_global_with_rel(gsym, GOT_TYPE_TLS_NOFFSET,
2503 target->rel_dyn_section(layout),
2504 elfcpp::R_386_TLS_TPOFF);
2506 else if (optimized_type != tls::TLSOPT_TO_LE)
2507 unsupported_reloc_global(object, r_type, gsym);
2510 case elfcpp::R_386_TLS_DESC_CALL:
2513 case elfcpp::R_386_TLS_LDM: // Local-dynamic
2514 if (optimized_type == tls::TLSOPT_NONE)
2516 // Create a GOT entry for the module index.
2517 target->got_mod_index_entry(symtab, layout, object);
2519 else if (optimized_type != tls::TLSOPT_TO_LE)
2520 unsupported_reloc_global(object, r_type, gsym);
2523 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
2526 case elfcpp::R_386_TLS_IE: // Initial-exec
2527 case elfcpp::R_386_TLS_IE_32:
2528 case elfcpp::R_386_TLS_GOTIE:
2529 layout->set_has_static_tls();
2530 if (optimized_type == tls::TLSOPT_NONE)
2532 // For the R_386_TLS_IE relocation, we need to create a
2533 // dynamic relocation when building a shared library.
2534 if (r_type == elfcpp::R_386_TLS_IE
2535 && parameters->options().shared())
2537 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
2538 rel_dyn->add_global_relative(gsym, elfcpp::R_386_RELATIVE,
2539 output_section, object,
2541 reloc.get_r_offset());
2543 // Create a GOT entry for the tp-relative offset.
2544 Output_data_got<32, false>* got
2545 = target->got_section(symtab, layout);
2546 unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_IE_32
2547 ? elfcpp::R_386_TLS_TPOFF32
2548 : elfcpp::R_386_TLS_TPOFF);
2549 unsigned int got_type = (r_type == elfcpp::R_386_TLS_IE_32
2550 ? GOT_TYPE_TLS_OFFSET
2551 : GOT_TYPE_TLS_NOFFSET);
2552 got->add_global_with_rel(gsym, got_type,
2553 target->rel_dyn_section(layout),
2556 else if (optimized_type != tls::TLSOPT_TO_LE)
2557 unsupported_reloc_global(object, r_type, gsym);
2560 case elfcpp::R_386_TLS_LE: // Local-exec
2561 case elfcpp::R_386_TLS_LE_32:
2562 layout->set_has_static_tls();
2563 if (parameters->options().shared())
2565 // We need to create a dynamic relocation.
2566 unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_LE_32
2567 ? elfcpp::R_386_TLS_TPOFF32
2568 : elfcpp::R_386_TLS_TPOFF);
2569 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
2570 rel_dyn->add_global(gsym, dyn_r_type, output_section, object,
2571 data_shndx, reloc.get_r_offset());
2581 case elfcpp::R_386_32PLT:
2582 case elfcpp::R_386_TLS_GD_32:
2583 case elfcpp::R_386_TLS_GD_PUSH:
2584 case elfcpp::R_386_TLS_GD_CALL:
2585 case elfcpp::R_386_TLS_GD_POP:
2586 case elfcpp::R_386_TLS_LDM_32:
2587 case elfcpp::R_386_TLS_LDM_PUSH:
2588 case elfcpp::R_386_TLS_LDM_CALL:
2589 case elfcpp::R_386_TLS_LDM_POP:
2590 case elfcpp::R_386_USED_BY_INTEL_200:
2592 unsupported_reloc_global(object, r_type, gsym);
2597 // Process relocations for gc.
2600 Target_i386::gc_process_relocs(Symbol_table* symtab,
2602 Sized_relobj_file<32, false>* object,
2603 unsigned int data_shndx,
2605 const unsigned char* prelocs,
2607 Output_section* output_section,
2608 bool needs_special_offset_handling,
2609 size_t local_symbol_count,
2610 const unsigned char* plocal_symbols)
2612 gold::gc_process_relocs<32, false, Target_i386, Scan, Classify_reloc>(
2621 needs_special_offset_handling,
2626 // Scan relocations for a section.
2629 Target_i386::scan_relocs(Symbol_table* symtab,
2631 Sized_relobj_file<32, false>* object,
2632 unsigned int data_shndx,
2633 unsigned int sh_type,
2634 const unsigned char* prelocs,
2636 Output_section* output_section,
2637 bool needs_special_offset_handling,
2638 size_t local_symbol_count,
2639 const unsigned char* plocal_symbols)
2641 if (sh_type == elfcpp::SHT_RELA)
2643 gold_error(_("%s: unsupported RELA reloc section"),
2644 object->name().c_str());
2648 gold::scan_relocs<32, false, Target_i386, Scan, Classify_reloc>(
2657 needs_special_offset_handling,
2662 // Finalize the sections.
2665 Target_i386::do_finalize_sections(
2667 const Input_objects*,
2668 Symbol_table* symtab)
2670 const Reloc_section* rel_plt = (this->plt_ == NULL
2672 : this->plt_->rel_plt());
2673 layout->add_target_dynamic_tags(true, this->got_plt_, rel_plt,
2674 this->rel_dyn_, true, false);
2676 // Emit any relocs we saved in an attempt to avoid generating COPY
2678 if (this->copy_relocs_.any_saved_relocs())
2679 this->copy_relocs_.emit(this->rel_dyn_section(layout));
2681 // Set the size of the _GLOBAL_OFFSET_TABLE_ symbol to the size of
2682 // the .got.plt section.
2683 Symbol* sym = this->global_offset_table_;
2686 uint32_t data_size = this->got_plt_->current_data_size();
2687 symtab->get_sized_symbol<32>(sym)->set_symsize(data_size);
2690 if (parameters->doing_static_link()
2691 && (this->plt_ == NULL || !this->plt_->has_irelative_section()))
2693 // If linking statically, make sure that the __rel_iplt symbols
2694 // were defined if necessary, even if we didn't create a PLT.
2695 static const Define_symbol_in_segment syms[] =
2698 "__rel_iplt_start", // name
2699 elfcpp::PT_LOAD, // segment_type
2700 elfcpp::PF_W, // segment_flags_set
2701 elfcpp::PF(0), // segment_flags_clear
2704 elfcpp::STT_NOTYPE, // type
2705 elfcpp::STB_GLOBAL, // binding
2706 elfcpp::STV_HIDDEN, // visibility
2708 Symbol::SEGMENT_START, // offset_from_base
2712 "__rel_iplt_end", // name
2713 elfcpp::PT_LOAD, // segment_type
2714 elfcpp::PF_W, // segment_flags_set
2715 elfcpp::PF(0), // segment_flags_clear
2718 elfcpp::STT_NOTYPE, // type
2719 elfcpp::STB_GLOBAL, // binding
2720 elfcpp::STV_HIDDEN, // visibility
2722 Symbol::SEGMENT_START, // offset_from_base
2727 symtab->define_symbols(layout, 2, syms,
2728 layout->script_options()->saw_sections_clause());
2732 // Return whether a direct absolute static relocation needs to be applied.
2733 // In cases where Scan::local() or Scan::global() has created
2734 // a dynamic relocation other than R_386_RELATIVE, the addend
2735 // of the relocation is carried in the data, and we must not
2736 // apply the static relocation.
2739 Target_i386::Relocate::should_apply_static_reloc(const Sized_symbol<32>* gsym,
2740 unsigned int r_type,
2742 Output_section* output_section)
2744 // If the output section is not allocated, then we didn't call
2745 // scan_relocs, we didn't create a dynamic reloc, and we must apply
2747 if ((output_section->flags() & elfcpp::SHF_ALLOC) == 0)
2750 int ref_flags = Scan::get_reference_flags(r_type);
2752 // For local symbols, we will have created a non-RELATIVE dynamic
2753 // relocation only if (a) the output is position independent,
2754 // (b) the relocation is absolute (not pc- or segment-relative), and
2755 // (c) the relocation is not 32 bits wide.
2757 return !(parameters->options().output_is_position_independent()
2758 && (ref_flags & Symbol::ABSOLUTE_REF)
2761 // For global symbols, we use the same helper routines used in the
2762 // scan pass. If we did not create a dynamic relocation, or if we
2763 // created a RELATIVE dynamic relocation, we should apply the static
2765 bool has_dyn = gsym->needs_dynamic_reloc(ref_flags);
2766 bool is_rel = (ref_flags & Symbol::ABSOLUTE_REF)
2767 && gsym->can_use_relative_reloc(ref_flags
2768 & Symbol::FUNCTION_CALL);
2769 return !has_dyn || is_rel;
2772 // Perform a relocation.
2775 Target_i386::Relocate::relocate(const Relocate_info<32, false>* relinfo,
2777 Target_i386* target,
2778 Output_section* output_section,
2780 const unsigned char* preloc,
2781 const Sized_symbol<32>* gsym,
2782 const Symbol_value<32>* psymval,
2783 unsigned char* view,
2784 elfcpp::Elf_types<32>::Elf_Addr address,
2785 section_size_type view_size)
2787 const elfcpp::Rel<32, false> rel(preloc);
2788 unsigned int r_type = elfcpp::elf_r_type<32>(rel.get_r_info());
2790 if (this->skip_call_tls_get_addr_)
2792 if ((r_type != elfcpp::R_386_PLT32
2793 && r_type != elfcpp::R_386_GOT32X
2794 && r_type != elfcpp::R_386_PC32)
2796 || strcmp(gsym->name(), "___tls_get_addr") != 0)
2798 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
2799 _("missing expected TLS relocation"));
2800 this->skip_call_tls_get_addr_ = false;
2804 this->skip_call_tls_get_addr_ = false;
2812 const Sized_relobj_file<32, false>* object = relinfo->object;
2814 // Pick the value to use for symbols defined in shared objects.
2815 Symbol_value<32> symval;
2817 && gsym->type() == elfcpp::STT_GNU_IFUNC
2818 && r_type == elfcpp::R_386_32
2819 && gsym->needs_dynamic_reloc(Scan::get_reference_flags(r_type))
2820 && gsym->can_use_relative_reloc(false)
2821 && !gsym->is_from_dynobj()
2822 && !gsym->is_undefined()
2823 && !gsym->is_preemptible())
2825 // In this case we are generating a R_386_IRELATIVE reloc. We
2826 // want to use the real value of the symbol, not the PLT offset.
2828 else if (gsym != NULL
2829 && gsym->use_plt_offset(Scan::get_reference_flags(r_type)))
2831 symval.set_output_value(target->plt_address_for_global(gsym));
2834 else if (gsym == NULL && psymval->is_ifunc_symbol())
2836 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
2837 if (object->local_has_plt_offset(r_sym))
2839 symval.set_output_value(target->plt_address_for_local(object, r_sym));
2848 case elfcpp::R_386_NONE:
2849 case elfcpp::R_386_GNU_VTINHERIT:
2850 case elfcpp::R_386_GNU_VTENTRY:
2853 case elfcpp::R_386_32:
2854 if (should_apply_static_reloc(gsym, r_type, true, output_section))
2855 Relocate_functions<32, false>::rel32(view, object, psymval);
2858 case elfcpp::R_386_PC32:
2859 if (should_apply_static_reloc(gsym, r_type, true, output_section))
2860 Relocate_functions<32, false>::pcrel32(view, object, psymval, address);
2863 case elfcpp::R_386_16:
2864 if (should_apply_static_reloc(gsym, r_type, false, output_section))
2865 Relocate_functions<32, false>::rel16(view, object, psymval);
2868 case elfcpp::R_386_PC16:
2869 if (should_apply_static_reloc(gsym, r_type, false, output_section))
2870 Relocate_functions<32, false>::pcrel16(view, object, psymval, address);
2873 case elfcpp::R_386_8:
2874 if (should_apply_static_reloc(gsym, r_type, false, output_section))
2875 Relocate_functions<32, false>::rel8(view, object, psymval);
2878 case elfcpp::R_386_PC8:
2879 if (should_apply_static_reloc(gsym, r_type, false, output_section))
2880 Relocate_functions<32, false>::pcrel8(view, object, psymval, address);
2883 case elfcpp::R_386_PLT32:
2884 gold_assert(gsym == NULL
2885 || gsym->has_plt_offset()
2886 || gsym->final_value_is_known()
2887 || (gsym->is_defined()
2888 && !gsym->is_from_dynobj()
2889 && !gsym->is_preemptible()));
2890 Relocate_functions<32, false>::pcrel32(view, object, psymval, address);
2893 case elfcpp::R_386_GOT32:
2894 case elfcpp::R_386_GOT32X:
2895 baseless = (view[-1] & 0xc7) == 0x5;
2896 // R_386_GOT32 and R_386_GOT32X don't work without base register
2897 // when generating a position-independent output file.
2899 && parameters->options().output_is_position_independent())
2902 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
2903 _("unexpected reloc %u against global symbol %s without base register in object file when generating a position-independent output file"),
2904 r_type, gsym->demangled_name().c_str());
2906 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
2907 _("unexpected reloc %u against local symbol without base register in object file when generating a position-independent output file"),
2912 // mov foo@GOT(%reg), %reg
2914 // lea foo@GOTOFF(%reg), %reg
2916 if (rel.get_r_offset() >= 2
2918 && ((gsym == NULL && !psymval->is_ifunc_symbol())
2920 && Target_i386::can_convert_mov_to_lea(gsym))))
2923 elfcpp::Elf_types<32>::Elf_Addr value;
2924 value = psymval->value(object, 0);
2925 // Don't subtract the .got.plt section address for baseless
2928 value -= target->got_plt_section()->address();
2929 Relocate_functions<32, false>::rel32(view, value);
2933 // The GOT pointer points to the end of the GOT section.
2934 // We need to subtract the size of the GOT section to get
2935 // the actual offset to use in the relocation.
2936 unsigned int got_offset = 0;
2939 gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
2940 got_offset = (gsym->got_offset(GOT_TYPE_STANDARD)
2941 - target->got_size());
2945 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
2946 gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD));
2947 got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD)
2948 - target->got_size());
2950 // Add the .got.plt section address for baseless addressing.
2952 got_offset += target->got_plt_section()->address();
2953 Relocate_functions<32, false>::rel32(view, got_offset);
2957 case elfcpp::R_386_GOTOFF:
2959 elfcpp::Elf_types<32>::Elf_Addr value;
2960 value = (psymval->value(object, 0)
2961 - target->got_plt_section()->address());
2962 Relocate_functions<32, false>::rel32(view, value);
2966 case elfcpp::R_386_GOTPC:
2968 elfcpp::Elf_types<32>::Elf_Addr value;
2969 value = target->got_plt_section()->address();
2970 Relocate_functions<32, false>::pcrel32(view, value, address);
2974 case elfcpp::R_386_COPY:
2975 case elfcpp::R_386_GLOB_DAT:
2976 case elfcpp::R_386_JUMP_SLOT:
2977 case elfcpp::R_386_RELATIVE:
2978 case elfcpp::R_386_IRELATIVE:
2979 // These are outstanding tls relocs, which are unexpected when
2981 case elfcpp::R_386_TLS_TPOFF:
2982 case elfcpp::R_386_TLS_DTPMOD32:
2983 case elfcpp::R_386_TLS_DTPOFF32:
2984 case elfcpp::R_386_TLS_TPOFF32:
2985 case elfcpp::R_386_TLS_DESC:
2986 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
2987 _("unexpected reloc %u in object file"),
2991 // These are initial tls relocs, which are expected when
2993 case elfcpp::R_386_TLS_GD: // Global-dynamic
2994 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url)
2995 case elfcpp::R_386_TLS_DESC_CALL:
2996 case elfcpp::R_386_TLS_LDM: // Local-dynamic
2997 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
2998 case elfcpp::R_386_TLS_IE: // Initial-exec
2999 case elfcpp::R_386_TLS_IE_32:
3000 case elfcpp::R_386_TLS_GOTIE:
3001 case elfcpp::R_386_TLS_LE: // Local-exec
3002 case elfcpp::R_386_TLS_LE_32:
3003 this->relocate_tls(relinfo, target, relnum, rel, r_type, gsym, psymval,
3004 view, address, view_size);
3007 case elfcpp::R_386_32PLT:
3008 case elfcpp::R_386_TLS_GD_32:
3009 case elfcpp::R_386_TLS_GD_PUSH:
3010 case elfcpp::R_386_TLS_GD_CALL:
3011 case elfcpp::R_386_TLS_GD_POP:
3012 case elfcpp::R_386_TLS_LDM_32:
3013 case elfcpp::R_386_TLS_LDM_PUSH:
3014 case elfcpp::R_386_TLS_LDM_CALL:
3015 case elfcpp::R_386_TLS_LDM_POP:
3016 case elfcpp::R_386_USED_BY_INTEL_200:
3018 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
3019 _("unsupported reloc %u"),
3027 // Perform a TLS relocation.
3030 Target_i386::Relocate::relocate_tls(const Relocate_info<32, false>* relinfo,
3031 Target_i386* target,
3033 const elfcpp::Rel<32, false>& rel,
3034 unsigned int r_type,
3035 const Sized_symbol<32>* gsym,
3036 const Symbol_value<32>* psymval,
3037 unsigned char* view,
3038 elfcpp::Elf_types<32>::Elf_Addr,
3039 section_size_type view_size)
3041 Output_segment* tls_segment = relinfo->layout->tls_segment();
3043 const Sized_relobj_file<32, false>* object = relinfo->object;
3045 elfcpp::Elf_types<32>::Elf_Addr value = psymval->value(object, 0);
3047 const bool is_final = (gsym == NULL
3048 ? !parameters->options().shared()
3049 : gsym->final_value_is_known());
3050 const tls::Tls_optimization optimized_type
3051 = Target_i386::optimize_tls_reloc(is_final, r_type);
3054 case elfcpp::R_386_TLS_GD: // Global-dynamic
3055 if (optimized_type == tls::TLSOPT_TO_LE)
3057 if (tls_segment == NULL)
3059 gold_assert(parameters->errors()->error_count() > 0
3060 || issue_undefined_symbol_error(gsym));
3063 this->tls_gd_to_le(relinfo, relnum, tls_segment,
3064 rel, r_type, value, view,
3070 unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE
3071 ? GOT_TYPE_TLS_NOFFSET
3072 : GOT_TYPE_TLS_PAIR);
3073 unsigned int got_offset;
3076 gold_assert(gsym->has_got_offset(got_type));
3077 got_offset = gsym->got_offset(got_type) - target->got_size();
3081 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
3082 gold_assert(object->local_has_got_offset(r_sym, got_type));
3083 got_offset = (object->local_got_offset(r_sym, got_type)
3084 - target->got_size());
3086 if (optimized_type == tls::TLSOPT_TO_IE)
3088 this->tls_gd_to_ie(relinfo, relnum, rel, r_type,
3089 got_offset, view, view_size);
3092 else if (optimized_type == tls::TLSOPT_NONE)
3094 // Relocate the field with the offset of the pair of GOT
3096 Relocate_functions<32, false>::rel32(view, got_offset);
3100 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
3101 _("unsupported reloc %u"),
3105 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url)
3106 case elfcpp::R_386_TLS_DESC_CALL:
3107 this->local_dynamic_type_ = LOCAL_DYNAMIC_GNU;
3108 if (optimized_type == tls::TLSOPT_TO_LE)
3110 if (tls_segment == NULL)
3112 gold_assert(parameters->errors()->error_count() > 0
3113 || issue_undefined_symbol_error(gsym));
3116 this->tls_desc_gd_to_le(relinfo, relnum, tls_segment,
3117 rel, r_type, value, view,
3123 unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE
3124 ? GOT_TYPE_TLS_NOFFSET
3125 : GOT_TYPE_TLS_DESC);
3126 unsigned int got_offset = 0;
3127 if (r_type == elfcpp::R_386_TLS_GOTDESC
3128 && optimized_type == tls::TLSOPT_NONE)
3130 // We created GOT entries in the .got.tlsdesc portion of
3131 // the .got.plt section, but the offset stored in the
3132 // symbol is the offset within .got.tlsdesc.
3133 got_offset = (target->got_size()
3134 + target->got_plt_section()->data_size());
3138 gold_assert(gsym->has_got_offset(got_type));
3139 got_offset += gsym->got_offset(got_type) - target->got_size();
3143 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
3144 gold_assert(object->local_has_got_offset(r_sym, got_type));
3145 got_offset += (object->local_got_offset(r_sym, got_type)
3146 - target->got_size());
3148 if (optimized_type == tls::TLSOPT_TO_IE)
3150 this->tls_desc_gd_to_ie(relinfo, relnum, rel, r_type,
3151 got_offset, view, view_size);
3154 else if (optimized_type == tls::TLSOPT_NONE)
3156 if (r_type == elfcpp::R_386_TLS_GOTDESC)
3158 // Relocate the field with the offset of the pair of GOT
3160 Relocate_functions<32, false>::rel32(view, got_offset);
3165 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
3166 _("unsupported reloc %u"),
3170 case elfcpp::R_386_TLS_LDM: // Local-dynamic
3171 if (this->local_dynamic_type_ == LOCAL_DYNAMIC_SUN)
3173 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
3174 _("both SUN and GNU model "
3175 "TLS relocations"));
3178 this->local_dynamic_type_ = LOCAL_DYNAMIC_GNU;
3179 if (optimized_type == tls::TLSOPT_TO_LE)
3181 if (tls_segment == NULL)
3183 gold_assert(parameters->errors()->error_count() > 0
3184 || issue_undefined_symbol_error(gsym));
3187 this->tls_ld_to_le(relinfo, relnum, tls_segment, rel, r_type,
3188 value, view, view_size);
3191 else if (optimized_type == tls::TLSOPT_NONE)
3193 // Relocate the field with the offset of the GOT entry for
3194 // the module index.
3195 unsigned int got_offset;
3196 got_offset = (target->got_mod_index_entry(NULL, NULL, NULL)
3197 - target->got_size());
3198 Relocate_functions<32, false>::rel32(view, got_offset);
3201 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
3202 _("unsupported reloc %u"),
3206 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
3207 if (optimized_type == tls::TLSOPT_TO_LE)
3209 // This reloc can appear in debugging sections, in which
3210 // case we must not convert to local-exec. We decide what
3211 // to do based on whether the section is marked as
3212 // containing executable code. That is what the GNU linker
3214 elfcpp::Shdr<32, false> shdr(relinfo->data_shdr);
3215 if ((shdr.get_sh_flags() & elfcpp::SHF_EXECINSTR) != 0)
3217 if (tls_segment == NULL)
3219 gold_assert(parameters->errors()->error_count() > 0
3220 || issue_undefined_symbol_error(gsym));
3223 value -= tls_segment->memsz();
3226 Relocate_functions<32, false>::rel32(view, value);
3229 case elfcpp::R_386_TLS_IE: // Initial-exec
3230 case elfcpp::R_386_TLS_GOTIE:
3231 case elfcpp::R_386_TLS_IE_32:
3232 if (optimized_type == tls::TLSOPT_TO_LE)
3234 if (tls_segment == NULL)
3236 gold_assert(parameters->errors()->error_count() > 0
3237 || issue_undefined_symbol_error(gsym));
3240 Target_i386::Relocate::tls_ie_to_le(relinfo, relnum, tls_segment,
3241 rel, r_type, value, view,
3245 else if (optimized_type == tls::TLSOPT_NONE)
3247 // Relocate the field with the offset of the GOT entry for
3248 // the tp-relative offset of the symbol.
3249 unsigned int got_type = (r_type == elfcpp::R_386_TLS_IE_32
3250 ? GOT_TYPE_TLS_OFFSET
3251 : GOT_TYPE_TLS_NOFFSET);
3252 unsigned int got_offset;
3255 gold_assert(gsym->has_got_offset(got_type));
3256 got_offset = gsym->got_offset(got_type);
3260 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
3261 gold_assert(object->local_has_got_offset(r_sym, got_type));
3262 got_offset = object->local_got_offset(r_sym, got_type);
3264 // For the R_386_TLS_IE relocation, we need to apply the
3265 // absolute address of the GOT entry.
3266 if (r_type == elfcpp::R_386_TLS_IE)
3267 got_offset += target->got_plt_section()->address();
3268 // All GOT offsets are relative to the end of the GOT.
3269 got_offset -= target->got_size();
3270 Relocate_functions<32, false>::rel32(view, got_offset);
3273 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
3274 _("unsupported reloc %u"),
3278 case elfcpp::R_386_TLS_LE: // Local-exec
3279 // If we're creating a shared library, a dynamic relocation will
3280 // have been created for this location, so do not apply it now.
3281 if (!parameters->options().shared())
3283 if (tls_segment == NULL)
3285 gold_assert(parameters->errors()->error_count() > 0
3286 || issue_undefined_symbol_error(gsym));
3289 value -= tls_segment->memsz();
3290 Relocate_functions<32, false>::rel32(view, value);
3294 case elfcpp::R_386_TLS_LE_32:
3295 // If we're creating a shared library, a dynamic relocation will
3296 // have been created for this location, so do not apply it now.
3297 if (!parameters->options().shared())
3299 if (tls_segment == NULL)
3301 gold_assert(parameters->errors()->error_count() > 0
3302 || issue_undefined_symbol_error(gsym));
3305 value = tls_segment->memsz() - value;
3306 Relocate_functions<32, false>::rel32(view, value);
3312 // Do a relocation in which we convert a TLS General-Dynamic to a
3316 Target_i386::Relocate::tls_gd_to_le(const Relocate_info<32, false>* relinfo,
3318 Output_segment* tls_segment,
3319 const elfcpp::Rel<32, false>& rel,
3321 elfcpp::Elf_types<32>::Elf_Addr value,
3322 unsigned char* view,
3323 section_size_type view_size)
3325 // leal foo(,%ebx,1),%eax; call ___tls_get_addr@PLT
3326 // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
3327 // leal foo(%ebx),%eax; call ___tls_get_addr@PLT
3328 // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
3329 // leal foo(%reg),%eax; call *___tls_get_addr@GOT(%reg)
3330 // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
3332 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
3333 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 9);
3335 unsigned char op1 = view[-1];
3336 unsigned char op2 = view[-2];
3337 unsigned char op3 = view[4];
3339 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3340 op2 == 0x8d || op2 == 0x04);
3341 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3342 op3 == 0xe8 || op3 == 0xff);
3348 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -3);
3349 tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[-3] == 0x8d);
3350 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3351 ((op1 & 0xc7) == 0x05 && op1 != (4 << 3)));
3352 memcpy(view - 3, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
3356 unsigned char reg = op1 & 7;
3357 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3358 ((op1 & 0xf8) == 0x80
3361 && (op3 == 0xe8 || (view[5] & 0x7) == reg)));
3363 || (rel.get_r_offset() + 9 < view_size
3364 && view[9] == 0x90))
3366 // There is an indirect call or a trailing nop. Use the size
3368 memcpy(view - 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
3373 // Use the five byte subl.
3374 memcpy(view - 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
3378 value = tls_segment->memsz() - value;
3379 Relocate_functions<32, false>::rel32(view + roff, value);
3381 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3383 this->skip_call_tls_get_addr_ = true;
3386 // Do a relocation in which we convert a TLS General-Dynamic to an
3390 Target_i386::Relocate::tls_gd_to_ie(const Relocate_info<32, false>* relinfo,
3392 const elfcpp::Rel<32, false>& rel,
3394 elfcpp::Elf_types<32>::Elf_Addr value,
3395 unsigned char* view,
3396 section_size_type view_size)
3398 // leal foo(,%ebx,1),%eax; call ___tls_get_addr@PLT
3399 // ==> movl %gs:0,%eax; addl foo@gotntpoff(%ebx),%eax
3400 // leal foo(%ebx),%eax; call ___tls_get_addr@PLT; nop
3401 // ==> movl %gs:0,%eax; addl foo@gotntpoff(%ebx),%eax
3402 // leal foo(%reg),%eax; call *___tls_get_addr@GOT(%reg)
3403 // ==> movl %gs:0,%eax; addl foo@gotntpoff(%reg),%eax
3405 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
3406 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 9);
3408 unsigned char op1 = view[-1];
3409 unsigned char op2 = view[-2];
3410 unsigned char op3 = view[4];
3412 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3413 op2 == 0x8d || op2 == 0x04);
3414 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3415 op3 == 0xe8 || op3 == 0xff);
3421 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -3);
3422 tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[-3] == 0x8d);
3423 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3424 ((op1 & 0xc7) == 0x05 && op1 != (4 << 3)));
3429 unsigned char reg = op1 & 7;
3430 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 10);
3431 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3432 ((op1 & 0xf8) == 0x80
3435 && ((op3 == 0xe8 && view[9] == 0x90)
3436 || (view[5] & 0x7) == reg)));
3440 memcpy(view + roff - 8, "\x65\xa1\0\0\0\0\x03\x83\0\0\0", 12);
3441 Relocate_functions<32, false>::rel32(view + roff, value);
3443 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3445 this->skip_call_tls_get_addr_ = true;
3448 // Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL
3449 // General-Dynamic to a Local-Exec.
3452 Target_i386::Relocate::tls_desc_gd_to_le(
3453 const Relocate_info<32, false>* relinfo,
3455 Output_segment* tls_segment,
3456 const elfcpp::Rel<32, false>& rel,
3457 unsigned int r_type,
3458 elfcpp::Elf_types<32>::Elf_Addr value,
3459 unsigned char* view,
3460 section_size_type view_size)
3462 if (r_type == elfcpp::R_386_TLS_GOTDESC)
3464 // leal foo@TLSDESC(%ebx), %eax
3465 // ==> leal foo@NTPOFF, %eax
3466 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
3467 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4);
3468 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3469 view[-2] == 0x8d && view[-1] == 0x83);
3471 value -= tls_segment->memsz();
3472 Relocate_functions<32, false>::rel32(view, value);
3476 // call *foo@TLSCALL(%eax)
3478 gold_assert(r_type == elfcpp::R_386_TLS_DESC_CALL);
3479 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 2);
3480 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3481 view[0] == 0xff && view[1] == 0x10);
3487 // Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL
3488 // General-Dynamic to an Initial-Exec.
3491 Target_i386::Relocate::tls_desc_gd_to_ie(
3492 const Relocate_info<32, false>* relinfo,
3494 const elfcpp::Rel<32, false>& rel,
3495 unsigned int r_type,
3496 elfcpp::Elf_types<32>::Elf_Addr value,
3497 unsigned char* view,
3498 section_size_type view_size)
3500 if (r_type == elfcpp::R_386_TLS_GOTDESC)
3502 // leal foo@TLSDESC(%ebx), %eax
3503 // ==> movl foo@GOTNTPOFF(%ebx), %eax
3504 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
3505 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4);
3506 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3507 view[-2] == 0x8d && view[-1] == 0x83);
3509 Relocate_functions<32, false>::rel32(view, value);
3513 // call *foo@TLSCALL(%eax)
3515 gold_assert(r_type == elfcpp::R_386_TLS_DESC_CALL);
3516 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 2);
3517 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3518 view[0] == 0xff && view[1] == 0x10);
3524 // Do a relocation in which we convert a TLS Local-Dynamic to a
3528 Target_i386::Relocate::tls_ld_to_le(const Relocate_info<32, false>* relinfo,
3531 const elfcpp::Rel<32, false>& rel,
3533 elfcpp::Elf_types<32>::Elf_Addr,
3534 unsigned char* view,
3535 section_size_type view_size)
3537 // leal foo(%ebx), %eax; call ___tls_get_addr@PLT
3538 // ==> movl %gs:0,%eax; nop; leal 0(%esi,1),%esi
3539 // leal foo(%reg), %eax; call call *___tls_get_addr@GOT(%reg)
3540 // ==> movl %gs:0,%eax; leal (%esi),%esi
3542 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
3544 unsigned char op1 = view[-1];
3545 unsigned char op2 = view[-2];
3546 unsigned char op3 = view[4];
3548 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3549 op3 == 0xe8 || op3 == 0xff);
3550 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size,
3551 op3 == 0xe8 ? 9 : 10);
3553 // FIXME: Does this test really always pass?
3554 tls::check_tls(relinfo, relnum, rel.get_r_offset(), op2 == 0x8d);
3556 unsigned char reg = op1 & 7;
3557 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3558 ((op1 & 0xf8) == 0x80
3561 && (op3 == 0xe8 || (view[5] & 0x7) == reg)));
3564 memcpy(view - 2, "\x65\xa1\0\0\0\0\x90\x8d\x74\x26\0", 11);
3566 memcpy(view - 2, "\x65\xa1\0\0\0\0\x8d\xb6\0\0\0\0", 12);
3568 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3570 this->skip_call_tls_get_addr_ = true;
3573 // Do a relocation in which we convert a TLS Initial-Exec to a
3577 Target_i386::Relocate::tls_ie_to_le(const Relocate_info<32, false>* relinfo,
3579 Output_segment* tls_segment,
3580 const elfcpp::Rel<32, false>& rel,
3581 unsigned int r_type,
3582 elfcpp::Elf_types<32>::Elf_Addr value,
3583 unsigned char* view,
3584 section_size_type view_size)
3586 // We have to actually change the instructions, which means that we
3587 // need to examine the opcodes to figure out which instruction we
3589 if (r_type == elfcpp::R_386_TLS_IE)
3591 // movl %gs:XX,%eax ==> movl $YY,%eax
3592 // movl %gs:XX,%reg ==> movl $YY,%reg
3593 // addl %gs:XX,%reg ==> addl $YY,%reg
3594 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -1);
3595 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4);
3597 unsigned char op1 = view[-1];
3600 // movl XX,%eax ==> movl $YY,%eax
3605 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
3607 unsigned char op2 = view[-2];
3610 // movl XX,%reg ==> movl $YY,%reg
3611 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3612 (op1 & 0xc7) == 0x05);
3614 view[-1] = 0xc0 | ((op1 >> 3) & 7);
3616 else if (op2 == 0x03)
3618 // addl XX,%reg ==> addl $YY,%reg
3619 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3620 (op1 & 0xc7) == 0x05);
3622 view[-1] = 0xc0 | ((op1 >> 3) & 7);
3625 tls::check_tls(relinfo, relnum, rel.get_r_offset(), 0);
3630 // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2
3631 // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2
3632 // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2
3633 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
3634 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4);
3636 unsigned char op1 = view[-1];
3637 unsigned char op2 = view[-2];
3638 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3639 (op1 & 0xc0) == 0x80 && (op1 & 7) != 4);
3642 // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2
3644 view[-1] = 0xc0 | ((op1 >> 3) & 7);
3646 else if (op2 == 0x2b)
3648 // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2
3650 view[-1] = 0xe8 | ((op1 >> 3) & 7);
3652 else if (op2 == 0x03)
3654 // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2
3656 view[-1] = 0xc0 | ((op1 >> 3) & 7);
3659 tls::check_tls(relinfo, relnum, rel.get_r_offset(), 0);
3662 value = tls_segment->memsz() - value;
3663 if (r_type == elfcpp::R_386_TLS_IE || r_type == elfcpp::R_386_TLS_GOTIE)
3666 Relocate_functions<32, false>::rel32(view, value);
3669 // Relocate section data.
3672 Target_i386::relocate_section(const Relocate_info<32, false>* relinfo,
3673 unsigned int sh_type,
3674 const unsigned char* prelocs,
3676 Output_section* output_section,
3677 bool needs_special_offset_handling,
3678 unsigned char* view,
3679 elfcpp::Elf_types<32>::Elf_Addr address,
3680 section_size_type view_size,
3681 const Reloc_symbol_changes* reloc_symbol_changes)
3683 gold_assert(sh_type == elfcpp::SHT_REL);
3685 gold::relocate_section<32, false, Target_i386, Relocate,
3686 gold::Default_comdat_behavior, Classify_reloc>(
3692 needs_special_offset_handling,
3696 reloc_symbol_changes);
3699 // Return the size of a relocation while scanning during a relocatable
3703 Target_i386::Classify_reloc::get_size_for_reloc(
3704 unsigned int r_type,
3709 case elfcpp::R_386_NONE:
3710 case elfcpp::R_386_GNU_VTINHERIT:
3711 case elfcpp::R_386_GNU_VTENTRY:
3712 case elfcpp::R_386_TLS_GD: // Global-dynamic
3713 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url)
3714 case elfcpp::R_386_TLS_DESC_CALL:
3715 case elfcpp::R_386_TLS_LDM: // Local-dynamic
3716 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
3717 case elfcpp::R_386_TLS_IE: // Initial-exec
3718 case elfcpp::R_386_TLS_IE_32:
3719 case elfcpp::R_386_TLS_GOTIE:
3720 case elfcpp::R_386_TLS_LE: // Local-exec
3721 case elfcpp::R_386_TLS_LE_32:
3724 case elfcpp::R_386_32:
3725 case elfcpp::R_386_PC32:
3726 case elfcpp::R_386_GOT32:
3727 case elfcpp::R_386_GOT32X:
3728 case elfcpp::R_386_PLT32:
3729 case elfcpp::R_386_GOTOFF:
3730 case elfcpp::R_386_GOTPC:
3733 case elfcpp::R_386_16:
3734 case elfcpp::R_386_PC16:
3737 case elfcpp::R_386_8:
3738 case elfcpp::R_386_PC8:
3741 // These are relocations which should only be seen by the
3742 // dynamic linker, and should never be seen here.
3743 case elfcpp::R_386_COPY:
3744 case elfcpp::R_386_GLOB_DAT:
3745 case elfcpp::R_386_JUMP_SLOT:
3746 case elfcpp::R_386_RELATIVE:
3747 case elfcpp::R_386_IRELATIVE:
3748 case elfcpp::R_386_TLS_TPOFF:
3749 case elfcpp::R_386_TLS_DTPMOD32:
3750 case elfcpp::R_386_TLS_DTPOFF32:
3751 case elfcpp::R_386_TLS_TPOFF32:
3752 case elfcpp::R_386_TLS_DESC:
3753 object->error(_("unexpected reloc %u in object file"), r_type);
3756 case elfcpp::R_386_32PLT:
3757 case elfcpp::R_386_TLS_GD_32:
3758 case elfcpp::R_386_TLS_GD_PUSH:
3759 case elfcpp::R_386_TLS_GD_CALL:
3760 case elfcpp::R_386_TLS_GD_POP:
3761 case elfcpp::R_386_TLS_LDM_32:
3762 case elfcpp::R_386_TLS_LDM_PUSH:
3763 case elfcpp::R_386_TLS_LDM_CALL:
3764 case elfcpp::R_386_TLS_LDM_POP:
3765 case elfcpp::R_386_USED_BY_INTEL_200:
3767 object->error(_("unsupported reloc %u in object file"), r_type);
3772 // Scan the relocs during a relocatable link.
3775 Target_i386::scan_relocatable_relocs(Symbol_table* symtab,
3777 Sized_relobj_file<32, false>* object,
3778 unsigned int data_shndx,
3779 unsigned int sh_type,
3780 const unsigned char* prelocs,
3782 Output_section* output_section,
3783 bool needs_special_offset_handling,
3784 size_t local_symbol_count,
3785 const unsigned char* plocal_symbols,
3786 Relocatable_relocs* rr)
3788 typedef gold::Default_scan_relocatable_relocs<Classify_reloc>
3789 Scan_relocatable_relocs;
3791 gold_assert(sh_type == elfcpp::SHT_REL);
3793 gold::scan_relocatable_relocs<32, false, Scan_relocatable_relocs>(
3801 needs_special_offset_handling,
3807 // Scan the relocs for --emit-relocs.
3810 Target_i386::emit_relocs_scan(Symbol_table* symtab,
3812 Sized_relobj_file<32, false>* object,
3813 unsigned int data_shndx,
3814 unsigned int sh_type,
3815 const unsigned char* prelocs,
3817 Output_section* output_section,
3818 bool needs_special_offset_handling,
3819 size_t local_symbol_count,
3820 const unsigned char* plocal_syms,
3821 Relocatable_relocs* rr)
3823 typedef gold::Default_classify_reloc<elfcpp::SHT_REL, 32, false>
3825 typedef gold::Default_emit_relocs_strategy<Classify_reloc>
3826 Emit_relocs_strategy;
3828 gold_assert(sh_type == elfcpp::SHT_REL);
3830 gold::scan_relocatable_relocs<32, false, Emit_relocs_strategy>(
3838 needs_special_offset_handling,
3844 // Emit relocations for a section.
3847 Target_i386::relocate_relocs(
3848 const Relocate_info<32, false>* relinfo,
3849 unsigned int sh_type,
3850 const unsigned char* prelocs,
3852 Output_section* output_section,
3853 elfcpp::Elf_types<32>::Elf_Off offset_in_output_section,
3854 unsigned char* view,
3855 elfcpp::Elf_types<32>::Elf_Addr view_address,
3856 section_size_type view_size,
3857 unsigned char* reloc_view,
3858 section_size_type reloc_view_size)
3860 gold_assert(sh_type == elfcpp::SHT_REL);
3862 gold::relocate_relocs<32, false, Classify_reloc>(
3867 offset_in_output_section,
3875 // Return the value to use for a dynamic which requires special
3876 // treatment. This is how we support equality comparisons of function
3877 // pointers across shared library boundaries, as described in the
3878 // processor specific ABI supplement.
3881 Target_i386::do_dynsym_value(const Symbol* gsym) const
3883 gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset());
3884 return this->plt_address_for_global(gsym);
3887 // Return a string used to fill a code section with nops to take up
3888 // the specified length.
3891 Target_i386::do_code_fill(section_size_type length) const
3895 // Build a jmp instruction to skip over the bytes.
3896 unsigned char jmp[5];
3898 elfcpp::Swap_unaligned<32, false>::writeval(jmp + 1, length - 5);
3899 return (std::string(reinterpret_cast<char*>(&jmp[0]), 5)
3900 + std::string(length - 5, static_cast<char>(0x90)));
3903 // Nop sequences of various lengths.
3904 const char nop1[1] = { '\x90' }; // nop
3905 const char nop2[2] = { '\x66', '\x90' }; // xchg %ax %ax
3906 const char nop3[3] = { '\x8d', '\x76', '\x00' }; // leal 0(%esi),%esi
3907 const char nop4[4] = { '\x8d', '\x74', '\x26', // leal 0(%esi,1),%esi
3909 const char nop5[5] = { '\x90', '\x8d', '\x74', // nop
3910 '\x26', '\x00' }; // leal 0(%esi,1),%esi
3911 const char nop6[6] = { '\x8d', '\xb6', '\x00', // leal 0L(%esi),%esi
3912 '\x00', '\x00', '\x00' };
3913 const char nop7[7] = { '\x8d', '\xb4', '\x26', // leal 0L(%esi,1),%esi
3914 '\x00', '\x00', '\x00',
3916 const char nop8[8] = { '\x90', '\x8d', '\xb4', // nop
3917 '\x26', '\x00', '\x00', // leal 0L(%esi,1),%esi
3919 const char nop9[9] = { '\x89', '\xf6', '\x8d', // movl %esi,%esi
3920 '\xbc', '\x27', '\x00', // leal 0L(%edi,1),%edi
3921 '\x00', '\x00', '\x00' };
3922 const char nop10[10] = { '\x8d', '\x76', '\x00', // leal 0(%esi),%esi
3923 '\x8d', '\xbc', '\x27', // leal 0L(%edi,1),%edi
3924 '\x00', '\x00', '\x00',
3926 const char nop11[11] = { '\x8d', '\x74', '\x26', // leal 0(%esi,1),%esi
3927 '\x00', '\x8d', '\xbc', // leal 0L(%edi,1),%edi
3928 '\x27', '\x00', '\x00',
3930 const char nop12[12] = { '\x8d', '\xb6', '\x00', // leal 0L(%esi),%esi
3931 '\x00', '\x00', '\x00', // leal 0L(%edi),%edi
3932 '\x8d', '\xbf', '\x00',
3933 '\x00', '\x00', '\x00' };
3934 const char nop13[13] = { '\x8d', '\xb6', '\x00', // leal 0L(%esi),%esi
3935 '\x00', '\x00', '\x00', // leal 0L(%edi,1),%edi
3936 '\x8d', '\xbc', '\x27',
3937 '\x00', '\x00', '\x00',
3939 const char nop14[14] = { '\x8d', '\xb4', '\x26', // leal 0L(%esi,1),%esi
3940 '\x00', '\x00', '\x00', // leal 0L(%edi,1),%edi
3941 '\x00', '\x8d', '\xbc',
3942 '\x27', '\x00', '\x00',
3944 const char nop15[15] = { '\xeb', '\x0d', '\x90', // jmp .+15
3945 '\x90', '\x90', '\x90', // nop,nop,nop,...
3946 '\x90', '\x90', '\x90',
3947 '\x90', '\x90', '\x90',
3948 '\x90', '\x90', '\x90' };
3950 const char* nops[16] = {
3952 nop1, nop2, nop3, nop4, nop5, nop6, nop7,
3953 nop8, nop9, nop10, nop11, nop12, nop13, nop14, nop15
3956 return std::string(nops[length], length);
3959 // Return the value to use for the base of a DW_EH_PE_datarel offset
3960 // in an FDE. Solaris and SVR4 use DW_EH_PE_datarel because their
3961 // assembler can not write out the difference between two labels in
3962 // different sections, so instead of using a pc-relative value they
3963 // use an offset from the GOT.
3966 Target_i386::do_ehframe_datarel_base() const
3968 gold_assert(this->global_offset_table_ != NULL);
3969 Symbol* sym = this->global_offset_table_;
3970 Sized_symbol<32>* ssym = static_cast<Sized_symbol<32>*>(sym);
3971 return ssym->value();
3974 // Return whether SYM should be treated as a call to a non-split
3975 // function. We don't want that to be true of a call to a
3976 // get_pc_thunk function.
3979 Target_i386::do_is_call_to_non_split(const Symbol* sym,
3980 const unsigned char*,
3981 const unsigned char*,
3982 section_size_type) const
3984 return (sym->type() == elfcpp::STT_FUNC
3985 && !is_prefix_of("__i686.get_pc_thunk.", sym->name()));
3988 // FNOFFSET in section SHNDX in OBJECT is the start of a function
3989 // compiled with -fsplit-stack. The function calls non-split-stack
3990 // code. We have to change the function so that it always ensures
3991 // that it has enough stack space to run some random function.
3994 Target_i386::do_calls_non_split(Relobj* object, unsigned int shndx,
3995 section_offset_type fnoffset,
3996 section_size_type fnsize,
3997 const unsigned char*,
3999 unsigned char* view,
4000 section_size_type view_size,
4002 std::string* to) const
4004 // The function starts with a comparison of the stack pointer and a
4005 // field in the TCB. This is followed by a jump.
4008 if (this->match_view(view, view_size, fnoffset, "\x65\x3b\x25", 3)
4011 // We will call __morestack if the carry flag is set after this
4012 // comparison. We turn the comparison into an stc instruction
4014 view[fnoffset] = '\xf9';
4015 this->set_view_to_nop(view, view_size, fnoffset + 1, 6);
4017 // lea NN(%esp),%ecx
4018 // lea NN(%esp),%edx
4019 else if ((this->match_view(view, view_size, fnoffset, "\x8d\x8c\x24", 3)
4020 || this->match_view(view, view_size, fnoffset, "\x8d\x94\x24", 3))
4023 // This is loading an offset from the stack pointer for a
4024 // comparison. The offset is negative, so we decrease the
4025 // offset by the amount of space we need for the stack. This
4026 // means we will avoid calling __morestack if there happens to
4027 // be plenty of space on the stack already.
4028 unsigned char* pval = view + fnoffset + 3;
4029 uint32_t val = elfcpp::Swap_unaligned<32, false>::readval(pval);
4030 val -= parameters->options().split_stack_adjust_size();
4031 elfcpp::Swap_unaligned<32, false>::writeval(pval, val);
4035 if (!object->has_no_split_stack())
4036 object->error(_("failed to match split-stack sequence at "
4037 "section %u offset %0zx"),
4038 shndx, static_cast<size_t>(fnoffset));
4042 // We have to change the function so that it calls
4043 // __morestack_non_split instead of __morestack. The former will
4044 // allocate additional stack space.
4045 *from = "__morestack";
4046 *to = "__morestack_non_split";
4049 // The selector for i386 object files. Note this is never instantiated
4050 // directly. It's only used in Target_selector_i386_nacl, below.
4052 class Target_selector_i386 : public Target_selector_freebsd
4055 Target_selector_i386()
4056 : Target_selector_freebsd(elfcpp::EM_386, 32, false,
4057 "elf32-i386", "elf32-i386-freebsd",
4062 do_instantiate_target()
4063 { return new Target_i386(); }
4066 // NaCl variant. It uses different PLT contents.
4068 class Output_data_plt_i386_nacl : public Output_data_plt_i386
4071 Output_data_plt_i386_nacl(Layout* layout,
4072 Output_data_got_plt_i386* got_plt,
4073 Output_data_space* got_irelative)
4074 : Output_data_plt_i386(layout, plt_entry_size, got_plt, got_irelative)
4078 virtual unsigned int
4079 do_get_plt_entry_size() const
4080 { return plt_entry_size; }
4083 do_add_eh_frame(Layout* layout)
4085 layout->add_eh_frame_for_plt(this, plt_eh_frame_cie, plt_eh_frame_cie_size,
4086 plt_eh_frame_fde, plt_eh_frame_fde_size);
4089 // The size of an entry in the PLT.
4090 static const int plt_entry_size = 64;
4092 // The .eh_frame unwind information for the PLT.
4093 static const int plt_eh_frame_fde_size = 32;
4094 static const unsigned char plt_eh_frame_fde[plt_eh_frame_fde_size];
4097 class Output_data_plt_i386_nacl_exec : public Output_data_plt_i386_nacl
4100 Output_data_plt_i386_nacl_exec(Layout* layout,
4101 Output_data_got_plt_i386* got_plt,
4102 Output_data_space* got_irelative)
4103 : Output_data_plt_i386_nacl(layout, got_plt, got_irelative)
4108 do_fill_first_plt_entry(unsigned char* pov,
4109 elfcpp::Elf_types<32>::Elf_Addr got_address);
4111 virtual unsigned int
4112 do_fill_plt_entry(unsigned char* pov,
4113 elfcpp::Elf_types<32>::Elf_Addr got_address,
4114 unsigned int got_offset,
4115 unsigned int plt_offset,
4116 unsigned int plt_rel_offset);
4119 // The first entry in the PLT for an executable.
4120 static const unsigned char first_plt_entry[plt_entry_size];
4122 // Other entries in the PLT for an executable.
4123 static const unsigned char plt_entry[plt_entry_size];
4126 class Output_data_plt_i386_nacl_dyn : public Output_data_plt_i386_nacl
4129 Output_data_plt_i386_nacl_dyn(Layout* layout,
4130 Output_data_got_plt_i386* got_plt,
4131 Output_data_space* got_irelative)
4132 : Output_data_plt_i386_nacl(layout, got_plt, got_irelative)
4137 do_fill_first_plt_entry(unsigned char* pov, elfcpp::Elf_types<32>::Elf_Addr);
4139 virtual unsigned int
4140 do_fill_plt_entry(unsigned char* pov,
4141 elfcpp::Elf_types<32>::Elf_Addr,
4142 unsigned int got_offset,
4143 unsigned int plt_offset,
4144 unsigned int plt_rel_offset);
4147 // The first entry in the PLT for a shared object.
4148 static const unsigned char first_plt_entry[plt_entry_size];
4150 // Other entries in the PLT for a shared object.
4151 static const unsigned char plt_entry[plt_entry_size];
4154 class Target_i386_nacl : public Target_i386
4158 : Target_i386(&i386_nacl_info)
4162 virtual Output_data_plt_i386*
4163 do_make_data_plt(Layout* layout,
4164 Output_data_got_plt_i386* got_plt,
4165 Output_data_space* got_irelative,
4169 return new Output_data_plt_i386_nacl_dyn(layout, got_plt, got_irelative);
4171 return new Output_data_plt_i386_nacl_exec(layout, got_plt, got_irelative);
4175 do_code_fill(section_size_type length) const;
4178 static const Target::Target_info i386_nacl_info;
4181 const Target::Target_info Target_i386_nacl::i386_nacl_info =
4184 false, // is_big_endian
4185 elfcpp::EM_386, // machine_code
4186 false, // has_make_symbol
4187 false, // has_resolve
4188 true, // has_code_fill
4189 true, // is_default_stack_executable
4190 true, // can_icf_inline_merge_sections
4192 "/lib/ld-nacl-x86-32.so.1", // dynamic_linker
4193 0x20000, // default_text_segment_address
4194 0x10000, // abi_pagesize (overridable by -z max-page-size)
4195 0x10000, // common_pagesize (overridable by -z common-page-size)
4196 true, // isolate_execinstr
4197 0x10000000, // rosegment_gap
4198 elfcpp::SHN_UNDEF, // small_common_shndx
4199 elfcpp::SHN_UNDEF, // large_common_shndx
4200 0, // small_common_section_flags
4201 0, // large_common_section_flags
4202 NULL, // attributes_section
4203 NULL, // attributes_vendor
4204 "_start", // entry_symbol_name
4205 32, // hash_entry_size
4208 #define NACLMASK 0xe0 // 32-byte alignment mask
4211 Output_data_plt_i386_nacl_exec::first_plt_entry[plt_entry_size] =
4213 0xff, 0x35, // pushl contents of memory address
4214 0, 0, 0, 0, // replaced with address of .got + 4
4215 0x8b, 0x0d, // movl contents of address, %ecx
4216 0, 0, 0, 0, // replaced with address of .got + 8
4217 0x83, 0xe1, NACLMASK, // andl $NACLMASK, %ecx
4218 0xff, 0xe1, // jmp *%ecx
4219 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4220 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4221 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4222 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4223 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4224 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4225 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4226 0x90, 0x90, 0x90, 0x90, 0x90
4230 Output_data_plt_i386_nacl_exec::do_fill_first_plt_entry(
4232 elfcpp::Elf_types<32>::Elf_Addr got_address)
4234 memcpy(pov, first_plt_entry, plt_entry_size);
4235 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_address + 4);
4236 elfcpp::Swap<32, false>::writeval(pov + 8, got_address + 8);
4239 // The first entry in the PLT for a shared object.
4242 Output_data_plt_i386_nacl_dyn::first_plt_entry[plt_entry_size] =
4244 0xff, 0xb3, 4, 0, 0, 0, // pushl 4(%ebx)
4245 0x8b, 0x4b, 0x08, // mov 0x8(%ebx), %ecx
4246 0x83, 0xe1, NACLMASK, // andl $NACLMASK, %ecx
4247 0xff, 0xe1, // jmp *%ecx
4248 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4249 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4250 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4251 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4252 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4253 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4254 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4255 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4256 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4257 0x90, 0x90, 0x90, 0x90, 0x90 // nops
4261 Output_data_plt_i386_nacl_dyn::do_fill_first_plt_entry(
4263 elfcpp::Elf_types<32>::Elf_Addr)
4265 memcpy(pov, first_plt_entry, plt_entry_size);
4268 // Subsequent entries in the PLT for an executable.
4271 Output_data_plt_i386_nacl_exec::plt_entry[plt_entry_size] =
4273 0x8b, 0x0d, // movl contents of address, %ecx */
4274 0, 0, 0, 0, // replaced with address of symbol in .got
4275 0x83, 0xe1, NACLMASK, // andl $NACLMASK, %ecx
4276 0xff, 0xe1, // jmp *%ecx
4278 // Pad to the next 32-byte boundary with nop instructions.
4280 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4281 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4283 // Lazy GOT entries point here (32-byte aligned).
4284 0x68, // pushl immediate
4285 0, 0, 0, 0, // replaced with offset into relocation table
4286 0xe9, // jmp relative
4287 0, 0, 0, 0, // replaced with offset to start of .plt
4289 // Pad to the next 32-byte boundary with nop instructions.
4290 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4291 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4296 Output_data_plt_i386_nacl_exec::do_fill_plt_entry(
4298 elfcpp::Elf_types<32>::Elf_Addr got_address,
4299 unsigned int got_offset,
4300 unsigned int plt_offset,
4301 unsigned int plt_rel_offset)
4303 memcpy(pov, plt_entry, plt_entry_size);
4304 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
4305 got_address + got_offset);
4306 elfcpp::Swap_unaligned<32, false>::writeval(pov + 33, plt_rel_offset);
4307 elfcpp::Swap<32, false>::writeval(pov + 38, - (plt_offset + 38 + 4));
4311 // Subsequent entries in the PLT for a shared object.
4314 Output_data_plt_i386_nacl_dyn::plt_entry[plt_entry_size] =
4316 0x8b, 0x8b, // movl offset(%ebx), %ecx
4317 0, 0, 0, 0, // replaced with offset of symbol in .got
4318 0x83, 0xe1, 0xe0, // andl $NACLMASK, %ecx
4319 0xff, 0xe1, // jmp *%ecx
4321 // Pad to the next 32-byte boundary with nop instructions.
4323 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4324 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4326 // Lazy GOT entries point here (32-byte aligned).
4327 0x68, // pushl immediate
4328 0, 0, 0, 0, // replaced with offset into relocation table.
4329 0xe9, // jmp relative
4330 0, 0, 0, 0, // replaced with offset to start of .plt.
4332 // Pad to the next 32-byte boundary with nop instructions.
4333 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4334 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4339 Output_data_plt_i386_nacl_dyn::do_fill_plt_entry(
4341 elfcpp::Elf_types<32>::Elf_Addr,
4342 unsigned int got_offset,
4343 unsigned int plt_offset,
4344 unsigned int plt_rel_offset)
4346 memcpy(pov, plt_entry, plt_entry_size);
4347 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_offset);
4348 elfcpp::Swap_unaligned<32, false>::writeval(pov + 33, plt_rel_offset);
4349 elfcpp::Swap<32, false>::writeval(pov + 38, - (plt_offset + 38 + 4));
4354 Output_data_plt_i386_nacl::plt_eh_frame_fde[plt_eh_frame_fde_size] =
4356 0, 0, 0, 0, // Replaced with offset to .plt.
4357 0, 0, 0, 0, // Replaced with size of .plt.
4358 0, // Augmentation size.
4359 elfcpp::DW_CFA_def_cfa_offset, 8, // DW_CFA_def_cfa_offset: 8.
4360 elfcpp::DW_CFA_advance_loc + 6, // Advance 6 to __PLT__ + 6.
4361 elfcpp::DW_CFA_def_cfa_offset, 12, // DW_CFA_def_cfa_offset: 12.
4362 elfcpp::DW_CFA_advance_loc + 58, // Advance 58 to __PLT__ + 64.
4363 elfcpp::DW_CFA_def_cfa_expression, // DW_CFA_def_cfa_expression.
4364 13, // Block length.
4365 elfcpp::DW_OP_breg4, 4, // Push %esp + 4.
4366 elfcpp::DW_OP_breg8, 0, // Push %eip.
4367 elfcpp::DW_OP_const1u, 63, // Push 0x3f.
4368 elfcpp::DW_OP_and, // & (%eip & 0x3f).
4369 elfcpp::DW_OP_const1u, 37, // Push 0x25.
4370 elfcpp::DW_OP_ge, // >= ((%eip & 0x3f) >= 0x25)
4371 elfcpp::DW_OP_lit2, // Push 2.
4372 elfcpp::DW_OP_shl, // << (((%eip & 0x3f) >= 0x25) << 2)
4373 elfcpp::DW_OP_plus, // + ((((%eip&0x3f)>=0x25)<<2)+%esp+4
4374 elfcpp::DW_CFA_nop, // Align to 32 bytes.
4378 // Return a string used to fill a code section with nops.
4379 // For NaCl, long NOPs are only valid if they do not cross
4380 // bundle alignment boundaries, so keep it simple with one-byte NOPs.
4382 Target_i386_nacl::do_code_fill(section_size_type length) const
4384 return std::string(length, static_cast<char>(0x90));
4387 // The selector for i386-nacl object files.
4389 class Target_selector_i386_nacl
4390 : public Target_selector_nacl<Target_selector_i386, Target_i386_nacl>
4393 Target_selector_i386_nacl()
4394 : Target_selector_nacl<Target_selector_i386,
4395 Target_i386_nacl>("x86-32",
4401 Target_selector_i386_nacl target_selector_i386;
4403 // IAMCU variant. It uses EM_IAMCU, not EM_386.
4405 class Target_iamcu : public Target_i386
4409 : Target_i386(&iamcu_info)
4413 // Information about this specific target which we pass to the
4414 // general Target structure.
4415 static const Target::Target_info iamcu_info;
4418 const Target::Target_info Target_iamcu::iamcu_info =
4421 false, // is_big_endian
4422 elfcpp::EM_IAMCU, // machine_code
4423 false, // has_make_symbol
4424 false, // has_resolve
4425 true, // has_code_fill
4426 true, // is_default_stack_executable
4427 true, // can_icf_inline_merge_sections
4429 "/usr/lib/libc.so.1", // dynamic_linker
4430 0x08048000, // default_text_segment_address
4431 0x1000, // abi_pagesize (overridable by -z max-page-size)
4432 0x1000, // common_pagesize (overridable by -z common-page-size)
4433 false, // isolate_execinstr
4435 elfcpp::SHN_UNDEF, // small_common_shndx
4436 elfcpp::SHN_UNDEF, // large_common_shndx
4437 0, // small_common_section_flags
4438 0, // large_common_section_flags
4439 NULL, // attributes_section
4440 NULL, // attributes_vendor
4441 "_start", // entry_symbol_name
4442 32, // hash_entry_size
4445 class Target_selector_iamcu : public Target_selector
4448 Target_selector_iamcu()
4449 : Target_selector(elfcpp::EM_IAMCU, 32, false, "elf32-iamcu",
4454 do_instantiate_target()
4455 { return new Target_iamcu(); }
4458 Target_selector_iamcu target_selector_iamcu;
4460 } // End anonymous namespace.