1 // i386.cc -- i386 target support for gold.
3 // Copyright (C) 2006-2016 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_PC32)
2795 || strcmp(gsym->name(), "___tls_get_addr") != 0)
2796 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
2797 _("missing expected TLS relocation"));
2800 this->skip_call_tls_get_addr_ = false;
2808 const Sized_relobj_file<32, false>* object = relinfo->object;
2810 // Pick the value to use for symbols defined in shared objects.
2811 Symbol_value<32> symval;
2813 && gsym->type() == elfcpp::STT_GNU_IFUNC
2814 && r_type == elfcpp::R_386_32
2815 && gsym->needs_dynamic_reloc(Scan::get_reference_flags(r_type))
2816 && gsym->can_use_relative_reloc(false)
2817 && !gsym->is_from_dynobj()
2818 && !gsym->is_undefined()
2819 && !gsym->is_preemptible())
2821 // In this case we are generating a R_386_IRELATIVE reloc. We
2822 // want to use the real value of the symbol, not the PLT offset.
2824 else if (gsym != NULL
2825 && gsym->use_plt_offset(Scan::get_reference_flags(r_type)))
2827 symval.set_output_value(target->plt_address_for_global(gsym));
2830 else if (gsym == NULL && psymval->is_ifunc_symbol())
2832 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
2833 if (object->local_has_plt_offset(r_sym))
2835 symval.set_output_value(target->plt_address_for_local(object, r_sym));
2844 case elfcpp::R_386_NONE:
2845 case elfcpp::R_386_GNU_VTINHERIT:
2846 case elfcpp::R_386_GNU_VTENTRY:
2849 case elfcpp::R_386_32:
2850 if (should_apply_static_reloc(gsym, r_type, true, output_section))
2851 Relocate_functions<32, false>::rel32(view, object, psymval);
2854 case elfcpp::R_386_PC32:
2855 if (should_apply_static_reloc(gsym, r_type, true, output_section))
2856 Relocate_functions<32, false>::pcrel32(view, object, psymval, address);
2859 case elfcpp::R_386_16:
2860 if (should_apply_static_reloc(gsym, r_type, false, output_section))
2861 Relocate_functions<32, false>::rel16(view, object, psymval);
2864 case elfcpp::R_386_PC16:
2865 if (should_apply_static_reloc(gsym, r_type, false, output_section))
2866 Relocate_functions<32, false>::pcrel16(view, object, psymval, address);
2869 case elfcpp::R_386_8:
2870 if (should_apply_static_reloc(gsym, r_type, false, output_section))
2871 Relocate_functions<32, false>::rel8(view, object, psymval);
2874 case elfcpp::R_386_PC8:
2875 if (should_apply_static_reloc(gsym, r_type, false, output_section))
2876 Relocate_functions<32, false>::pcrel8(view, object, psymval, address);
2879 case elfcpp::R_386_PLT32:
2880 gold_assert(gsym == NULL
2881 || gsym->has_plt_offset()
2882 || gsym->final_value_is_known()
2883 || (gsym->is_defined()
2884 && !gsym->is_from_dynobj()
2885 && !gsym->is_preemptible()));
2886 Relocate_functions<32, false>::pcrel32(view, object, psymval, address);
2889 case elfcpp::R_386_GOT32:
2890 case elfcpp::R_386_GOT32X:
2891 baseless = (view[-1] & 0xc7) == 0x5;
2892 // R_386_GOT32 and R_386_GOT32X don't work without base register
2893 // when generating a position-independent output file.
2895 && parameters->options().output_is_position_independent())
2898 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
2899 _("unexpected reloc %u against global symbol %s without base register in object file when generating a position-independent output file"),
2900 r_type, gsym->demangled_name().c_str());
2902 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
2903 _("unexpected reloc %u against local symbol without base register in object file when generating a position-independent output file"),
2908 // mov foo@GOT(%reg), %reg
2910 // lea foo@GOTOFF(%reg), %reg
2912 if (rel.get_r_offset() >= 2
2914 && ((gsym == NULL && !psymval->is_ifunc_symbol())
2916 && Target_i386::can_convert_mov_to_lea(gsym))))
2919 elfcpp::Elf_types<32>::Elf_Addr value;
2920 value = psymval->value(object, 0);
2921 // Don't subtract the .got.plt section address for baseless
2924 value -= target->got_plt_section()->address();
2925 Relocate_functions<32, false>::rel32(view, value);
2929 // The GOT pointer points to the end of the GOT section.
2930 // We need to subtract the size of the GOT section to get
2931 // the actual offset to use in the relocation.
2932 unsigned int got_offset = 0;
2935 gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
2936 got_offset = (gsym->got_offset(GOT_TYPE_STANDARD)
2937 - target->got_size());
2941 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
2942 gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD));
2943 got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD)
2944 - target->got_size());
2946 // Add the .got.plt section address for baseless addressing.
2948 got_offset += target->got_plt_section()->address();
2949 Relocate_functions<32, false>::rel32(view, got_offset);
2953 case elfcpp::R_386_GOTOFF:
2955 elfcpp::Elf_types<32>::Elf_Addr value;
2956 value = (psymval->value(object, 0)
2957 - target->got_plt_section()->address());
2958 Relocate_functions<32, false>::rel32(view, value);
2962 case elfcpp::R_386_GOTPC:
2964 elfcpp::Elf_types<32>::Elf_Addr value;
2965 value = target->got_plt_section()->address();
2966 Relocate_functions<32, false>::pcrel32(view, value, address);
2970 case elfcpp::R_386_COPY:
2971 case elfcpp::R_386_GLOB_DAT:
2972 case elfcpp::R_386_JUMP_SLOT:
2973 case elfcpp::R_386_RELATIVE:
2974 case elfcpp::R_386_IRELATIVE:
2975 // These are outstanding tls relocs, which are unexpected when
2977 case elfcpp::R_386_TLS_TPOFF:
2978 case elfcpp::R_386_TLS_DTPMOD32:
2979 case elfcpp::R_386_TLS_DTPOFF32:
2980 case elfcpp::R_386_TLS_TPOFF32:
2981 case elfcpp::R_386_TLS_DESC:
2982 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
2983 _("unexpected reloc %u in object file"),
2987 // These are initial tls relocs, which are expected when
2989 case elfcpp::R_386_TLS_GD: // Global-dynamic
2990 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url)
2991 case elfcpp::R_386_TLS_DESC_CALL:
2992 case elfcpp::R_386_TLS_LDM: // Local-dynamic
2993 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
2994 case elfcpp::R_386_TLS_IE: // Initial-exec
2995 case elfcpp::R_386_TLS_IE_32:
2996 case elfcpp::R_386_TLS_GOTIE:
2997 case elfcpp::R_386_TLS_LE: // Local-exec
2998 case elfcpp::R_386_TLS_LE_32:
2999 this->relocate_tls(relinfo, target, relnum, rel, r_type, gsym, psymval,
3000 view, address, view_size);
3003 case elfcpp::R_386_32PLT:
3004 case elfcpp::R_386_TLS_GD_32:
3005 case elfcpp::R_386_TLS_GD_PUSH:
3006 case elfcpp::R_386_TLS_GD_CALL:
3007 case elfcpp::R_386_TLS_GD_POP:
3008 case elfcpp::R_386_TLS_LDM_32:
3009 case elfcpp::R_386_TLS_LDM_PUSH:
3010 case elfcpp::R_386_TLS_LDM_CALL:
3011 case elfcpp::R_386_TLS_LDM_POP:
3012 case elfcpp::R_386_USED_BY_INTEL_200:
3014 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
3015 _("unsupported reloc %u"),
3023 // Perform a TLS relocation.
3026 Target_i386::Relocate::relocate_tls(const Relocate_info<32, false>* relinfo,
3027 Target_i386* target,
3029 const elfcpp::Rel<32, false>& rel,
3030 unsigned int r_type,
3031 const Sized_symbol<32>* gsym,
3032 const Symbol_value<32>* psymval,
3033 unsigned char* view,
3034 elfcpp::Elf_types<32>::Elf_Addr,
3035 section_size_type view_size)
3037 Output_segment* tls_segment = relinfo->layout->tls_segment();
3039 const Sized_relobj_file<32, false>* object = relinfo->object;
3041 elfcpp::Elf_types<32>::Elf_Addr value = psymval->value(object, 0);
3043 const bool is_final = (gsym == NULL
3044 ? !parameters->options().shared()
3045 : gsym->final_value_is_known());
3046 const tls::Tls_optimization optimized_type
3047 = Target_i386::optimize_tls_reloc(is_final, r_type);
3050 case elfcpp::R_386_TLS_GD: // Global-dynamic
3051 if (optimized_type == tls::TLSOPT_TO_LE)
3053 if (tls_segment == NULL)
3055 gold_assert(parameters->errors()->error_count() > 0
3056 || issue_undefined_symbol_error(gsym));
3059 this->tls_gd_to_le(relinfo, relnum, tls_segment,
3060 rel, r_type, value, view,
3066 unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE
3067 ? GOT_TYPE_TLS_NOFFSET
3068 : GOT_TYPE_TLS_PAIR);
3069 unsigned int got_offset;
3072 gold_assert(gsym->has_got_offset(got_type));
3073 got_offset = gsym->got_offset(got_type) - target->got_size();
3077 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
3078 gold_assert(object->local_has_got_offset(r_sym, got_type));
3079 got_offset = (object->local_got_offset(r_sym, got_type)
3080 - target->got_size());
3082 if (optimized_type == tls::TLSOPT_TO_IE)
3084 this->tls_gd_to_ie(relinfo, relnum, rel, r_type,
3085 got_offset, view, view_size);
3088 else if (optimized_type == tls::TLSOPT_NONE)
3090 // Relocate the field with the offset of the pair of GOT
3092 Relocate_functions<32, false>::rel32(view, got_offset);
3096 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
3097 _("unsupported reloc %u"),
3101 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url)
3102 case elfcpp::R_386_TLS_DESC_CALL:
3103 this->local_dynamic_type_ = LOCAL_DYNAMIC_GNU;
3104 if (optimized_type == tls::TLSOPT_TO_LE)
3106 if (tls_segment == NULL)
3108 gold_assert(parameters->errors()->error_count() > 0
3109 || issue_undefined_symbol_error(gsym));
3112 this->tls_desc_gd_to_le(relinfo, relnum, tls_segment,
3113 rel, r_type, value, view,
3119 unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE
3120 ? GOT_TYPE_TLS_NOFFSET
3121 : GOT_TYPE_TLS_DESC);
3122 unsigned int got_offset = 0;
3123 if (r_type == elfcpp::R_386_TLS_GOTDESC
3124 && optimized_type == tls::TLSOPT_NONE)
3126 // We created GOT entries in the .got.tlsdesc portion of
3127 // the .got.plt section, but the offset stored in the
3128 // symbol is the offset within .got.tlsdesc.
3129 got_offset = (target->got_size()
3130 + target->got_plt_section()->data_size());
3134 gold_assert(gsym->has_got_offset(got_type));
3135 got_offset += gsym->got_offset(got_type) - target->got_size();
3139 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
3140 gold_assert(object->local_has_got_offset(r_sym, got_type));
3141 got_offset += (object->local_got_offset(r_sym, got_type)
3142 - target->got_size());
3144 if (optimized_type == tls::TLSOPT_TO_IE)
3146 this->tls_desc_gd_to_ie(relinfo, relnum, rel, r_type,
3147 got_offset, view, view_size);
3150 else if (optimized_type == tls::TLSOPT_NONE)
3152 if (r_type == elfcpp::R_386_TLS_GOTDESC)
3154 // Relocate the field with the offset of the pair of GOT
3156 Relocate_functions<32, false>::rel32(view, got_offset);
3161 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
3162 _("unsupported reloc %u"),
3166 case elfcpp::R_386_TLS_LDM: // Local-dynamic
3167 if (this->local_dynamic_type_ == LOCAL_DYNAMIC_SUN)
3169 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
3170 _("both SUN and GNU model "
3171 "TLS relocations"));
3174 this->local_dynamic_type_ = LOCAL_DYNAMIC_GNU;
3175 if (optimized_type == tls::TLSOPT_TO_LE)
3177 if (tls_segment == NULL)
3179 gold_assert(parameters->errors()->error_count() > 0
3180 || issue_undefined_symbol_error(gsym));
3183 this->tls_ld_to_le(relinfo, relnum, tls_segment, rel, r_type,
3184 value, view, view_size);
3187 else if (optimized_type == tls::TLSOPT_NONE)
3189 // Relocate the field with the offset of the GOT entry for
3190 // the module index.
3191 unsigned int got_offset;
3192 got_offset = (target->got_mod_index_entry(NULL, NULL, NULL)
3193 - target->got_size());
3194 Relocate_functions<32, false>::rel32(view, got_offset);
3197 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
3198 _("unsupported reloc %u"),
3202 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
3203 if (optimized_type == tls::TLSOPT_TO_LE)
3205 // This reloc can appear in debugging sections, in which
3206 // case we must not convert to local-exec. We decide what
3207 // to do based on whether the section is marked as
3208 // containing executable code. That is what the GNU linker
3210 elfcpp::Shdr<32, false> shdr(relinfo->data_shdr);
3211 if ((shdr.get_sh_flags() & elfcpp::SHF_EXECINSTR) != 0)
3213 if (tls_segment == NULL)
3215 gold_assert(parameters->errors()->error_count() > 0
3216 || issue_undefined_symbol_error(gsym));
3219 value -= tls_segment->memsz();
3222 Relocate_functions<32, false>::rel32(view, value);
3225 case elfcpp::R_386_TLS_IE: // Initial-exec
3226 case elfcpp::R_386_TLS_GOTIE:
3227 case elfcpp::R_386_TLS_IE_32:
3228 if (optimized_type == tls::TLSOPT_TO_LE)
3230 if (tls_segment == NULL)
3232 gold_assert(parameters->errors()->error_count() > 0
3233 || issue_undefined_symbol_error(gsym));
3236 Target_i386::Relocate::tls_ie_to_le(relinfo, relnum, tls_segment,
3237 rel, r_type, value, view,
3241 else if (optimized_type == tls::TLSOPT_NONE)
3243 // Relocate the field with the offset of the GOT entry for
3244 // the tp-relative offset of the symbol.
3245 unsigned int got_type = (r_type == elfcpp::R_386_TLS_IE_32
3246 ? GOT_TYPE_TLS_OFFSET
3247 : GOT_TYPE_TLS_NOFFSET);
3248 unsigned int got_offset;
3251 gold_assert(gsym->has_got_offset(got_type));
3252 got_offset = gsym->got_offset(got_type);
3256 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
3257 gold_assert(object->local_has_got_offset(r_sym, got_type));
3258 got_offset = object->local_got_offset(r_sym, got_type);
3260 // For the R_386_TLS_IE relocation, we need to apply the
3261 // absolute address of the GOT entry.
3262 if (r_type == elfcpp::R_386_TLS_IE)
3263 got_offset += target->got_plt_section()->address();
3264 // All GOT offsets are relative to the end of the GOT.
3265 got_offset -= target->got_size();
3266 Relocate_functions<32, false>::rel32(view, got_offset);
3269 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
3270 _("unsupported reloc %u"),
3274 case elfcpp::R_386_TLS_LE: // Local-exec
3275 // If we're creating a shared library, a dynamic relocation will
3276 // have been created for this location, so do not apply it now.
3277 if (!parameters->options().shared())
3279 if (tls_segment == NULL)
3281 gold_assert(parameters->errors()->error_count() > 0
3282 || issue_undefined_symbol_error(gsym));
3285 value -= tls_segment->memsz();
3286 Relocate_functions<32, false>::rel32(view, value);
3290 case elfcpp::R_386_TLS_LE_32:
3291 // If we're creating a shared library, a dynamic relocation will
3292 // have been created for this location, so do not apply it now.
3293 if (!parameters->options().shared())
3295 if (tls_segment == NULL)
3297 gold_assert(parameters->errors()->error_count() > 0
3298 || issue_undefined_symbol_error(gsym));
3301 value = tls_segment->memsz() - value;
3302 Relocate_functions<32, false>::rel32(view, value);
3308 // Do a relocation in which we convert a TLS General-Dynamic to a
3312 Target_i386::Relocate::tls_gd_to_le(const Relocate_info<32, false>* relinfo,
3314 Output_segment* tls_segment,
3315 const elfcpp::Rel<32, false>& rel,
3317 elfcpp::Elf_types<32>::Elf_Addr value,
3318 unsigned char* view,
3319 section_size_type view_size)
3321 // leal foo(,%reg,1),%eax; call ___tls_get_addr
3322 // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
3323 // leal foo(%reg),%eax; call ___tls_get_addr
3324 // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
3326 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
3327 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 9);
3329 unsigned char op1 = view[-1];
3330 unsigned char op2 = view[-2];
3332 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3333 op2 == 0x8d || op2 == 0x04);
3334 tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[4] == 0xe8);
3340 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -3);
3341 tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[-3] == 0x8d);
3342 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3343 ((op1 & 0xc7) == 0x05 && op1 != (4 << 3)));
3344 memcpy(view - 3, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
3348 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3349 (op1 & 0xf8) == 0x80 && (op1 & 7) != 4);
3350 if (rel.get_r_offset() + 9 < view_size
3353 // There is a trailing nop. Use the size byte subl.
3354 memcpy(view - 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
3359 // Use the five byte subl.
3360 memcpy(view - 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
3364 value = tls_segment->memsz() - value;
3365 Relocate_functions<32, false>::rel32(view + roff, value);
3367 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3369 this->skip_call_tls_get_addr_ = true;
3372 // Do a relocation in which we convert a TLS General-Dynamic to an
3376 Target_i386::Relocate::tls_gd_to_ie(const Relocate_info<32, false>* relinfo,
3378 const elfcpp::Rel<32, false>& rel,
3380 elfcpp::Elf_types<32>::Elf_Addr value,
3381 unsigned char* view,
3382 section_size_type view_size)
3384 // leal foo(,%ebx,1),%eax; call ___tls_get_addr
3385 // ==> movl %gs:0,%eax; addl foo@gotntpoff(%ebx),%eax
3386 // leal foo(%ebx),%eax; call ___tls_get_addr; nop
3387 // ==> movl %gs:0,%eax; addl foo@gotntpoff(%ebx),%eax
3389 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
3390 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 9);
3392 unsigned char op1 = view[-1];
3393 unsigned char op2 = view[-2];
3395 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3396 op2 == 0x8d || op2 == 0x04);
3397 tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[4] == 0xe8);
3403 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -3);
3404 tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[-3] == 0x8d);
3405 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3406 ((op1 & 0xc7) == 0x05 && op1 != (4 << 3)));
3411 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 10);
3412 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3413 (op1 & 0xf8) == 0x80 && (op1 & 7) != 4);
3414 tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[9] == 0x90);
3418 memcpy(view + roff - 8, "\x65\xa1\0\0\0\0\x03\x83\0\0\0", 12);
3419 Relocate_functions<32, false>::rel32(view + roff, value);
3421 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3423 this->skip_call_tls_get_addr_ = true;
3426 // Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL
3427 // General-Dynamic to a Local-Exec.
3430 Target_i386::Relocate::tls_desc_gd_to_le(
3431 const Relocate_info<32, false>* relinfo,
3433 Output_segment* tls_segment,
3434 const elfcpp::Rel<32, false>& rel,
3435 unsigned int r_type,
3436 elfcpp::Elf_types<32>::Elf_Addr value,
3437 unsigned char* view,
3438 section_size_type view_size)
3440 if (r_type == elfcpp::R_386_TLS_GOTDESC)
3442 // leal foo@TLSDESC(%ebx), %eax
3443 // ==> leal foo@NTPOFF, %eax
3444 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
3445 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4);
3446 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3447 view[-2] == 0x8d && view[-1] == 0x83);
3449 value -= tls_segment->memsz();
3450 Relocate_functions<32, false>::rel32(view, value);
3454 // call *foo@TLSCALL(%eax)
3456 gold_assert(r_type == elfcpp::R_386_TLS_DESC_CALL);
3457 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 2);
3458 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3459 view[0] == 0xff && view[1] == 0x10);
3465 // Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL
3466 // General-Dynamic to an Initial-Exec.
3469 Target_i386::Relocate::tls_desc_gd_to_ie(
3470 const Relocate_info<32, false>* relinfo,
3472 const elfcpp::Rel<32, false>& rel,
3473 unsigned int r_type,
3474 elfcpp::Elf_types<32>::Elf_Addr value,
3475 unsigned char* view,
3476 section_size_type view_size)
3478 if (r_type == elfcpp::R_386_TLS_GOTDESC)
3480 // leal foo@TLSDESC(%ebx), %eax
3481 // ==> movl foo@GOTNTPOFF(%ebx), %eax
3482 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
3483 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4);
3484 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3485 view[-2] == 0x8d && view[-1] == 0x83);
3487 Relocate_functions<32, false>::rel32(view, value);
3491 // call *foo@TLSCALL(%eax)
3493 gold_assert(r_type == elfcpp::R_386_TLS_DESC_CALL);
3494 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 2);
3495 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3496 view[0] == 0xff && view[1] == 0x10);
3502 // Do a relocation in which we convert a TLS Local-Dynamic to a
3506 Target_i386::Relocate::tls_ld_to_le(const Relocate_info<32, false>* relinfo,
3509 const elfcpp::Rel<32, false>& rel,
3511 elfcpp::Elf_types<32>::Elf_Addr,
3512 unsigned char* view,
3513 section_size_type view_size)
3515 // leal foo(%reg), %eax; call ___tls_get_addr
3516 // ==> movl %gs:0,%eax; nop; leal 0(%esi,1),%esi
3518 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
3519 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 9);
3521 // FIXME: Does this test really always pass?
3522 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3523 view[-2] == 0x8d && view[-1] == 0x83);
3525 tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[4] == 0xe8);
3527 memcpy(view - 2, "\x65\xa1\0\0\0\0\x90\x8d\x74\x26\0", 11);
3529 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3531 this->skip_call_tls_get_addr_ = true;
3534 // Do a relocation in which we convert a TLS Initial-Exec to a
3538 Target_i386::Relocate::tls_ie_to_le(const Relocate_info<32, false>* relinfo,
3540 Output_segment* tls_segment,
3541 const elfcpp::Rel<32, false>& rel,
3542 unsigned int r_type,
3543 elfcpp::Elf_types<32>::Elf_Addr value,
3544 unsigned char* view,
3545 section_size_type view_size)
3547 // We have to actually change the instructions, which means that we
3548 // need to examine the opcodes to figure out which instruction we
3550 if (r_type == elfcpp::R_386_TLS_IE)
3552 // movl %gs:XX,%eax ==> movl $YY,%eax
3553 // movl %gs:XX,%reg ==> movl $YY,%reg
3554 // addl %gs:XX,%reg ==> addl $YY,%reg
3555 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -1);
3556 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4);
3558 unsigned char op1 = view[-1];
3561 // movl XX,%eax ==> movl $YY,%eax
3566 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
3568 unsigned char op2 = view[-2];
3571 // movl XX,%reg ==> movl $YY,%reg
3572 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3573 (op1 & 0xc7) == 0x05);
3575 view[-1] = 0xc0 | ((op1 >> 3) & 7);
3577 else if (op2 == 0x03)
3579 // addl XX,%reg ==> addl $YY,%reg
3580 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3581 (op1 & 0xc7) == 0x05);
3583 view[-1] = 0xc0 | ((op1 >> 3) & 7);
3586 tls::check_tls(relinfo, relnum, rel.get_r_offset(), 0);
3591 // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2
3592 // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2
3593 // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2
3594 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
3595 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4);
3597 unsigned char op1 = view[-1];
3598 unsigned char op2 = view[-2];
3599 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3600 (op1 & 0xc0) == 0x80 && (op1 & 7) != 4);
3603 // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2
3605 view[-1] = 0xc0 | ((op1 >> 3) & 7);
3607 else if (op2 == 0x2b)
3609 // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2
3611 view[-1] = 0xe8 | ((op1 >> 3) & 7);
3613 else if (op2 == 0x03)
3615 // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2
3617 view[-1] = 0xc0 | ((op1 >> 3) & 7);
3620 tls::check_tls(relinfo, relnum, rel.get_r_offset(), 0);
3623 value = tls_segment->memsz() - value;
3624 if (r_type == elfcpp::R_386_TLS_IE || r_type == elfcpp::R_386_TLS_GOTIE)
3627 Relocate_functions<32, false>::rel32(view, value);
3630 // Relocate section data.
3633 Target_i386::relocate_section(const Relocate_info<32, false>* relinfo,
3634 unsigned int sh_type,
3635 const unsigned char* prelocs,
3637 Output_section* output_section,
3638 bool needs_special_offset_handling,
3639 unsigned char* view,
3640 elfcpp::Elf_types<32>::Elf_Addr address,
3641 section_size_type view_size,
3642 const Reloc_symbol_changes* reloc_symbol_changes)
3644 gold_assert(sh_type == elfcpp::SHT_REL);
3646 gold::relocate_section<32, false, Target_i386, Relocate,
3647 gold::Default_comdat_behavior, Classify_reloc>(
3653 needs_special_offset_handling,
3657 reloc_symbol_changes);
3660 // Return the size of a relocation while scanning during a relocatable
3664 Target_i386::Classify_reloc::get_size_for_reloc(
3665 unsigned int r_type,
3670 case elfcpp::R_386_NONE:
3671 case elfcpp::R_386_GNU_VTINHERIT:
3672 case elfcpp::R_386_GNU_VTENTRY:
3673 case elfcpp::R_386_TLS_GD: // Global-dynamic
3674 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url)
3675 case elfcpp::R_386_TLS_DESC_CALL:
3676 case elfcpp::R_386_TLS_LDM: // Local-dynamic
3677 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
3678 case elfcpp::R_386_TLS_IE: // Initial-exec
3679 case elfcpp::R_386_TLS_IE_32:
3680 case elfcpp::R_386_TLS_GOTIE:
3681 case elfcpp::R_386_TLS_LE: // Local-exec
3682 case elfcpp::R_386_TLS_LE_32:
3685 case elfcpp::R_386_32:
3686 case elfcpp::R_386_PC32:
3687 case elfcpp::R_386_GOT32:
3688 case elfcpp::R_386_GOT32X:
3689 case elfcpp::R_386_PLT32:
3690 case elfcpp::R_386_GOTOFF:
3691 case elfcpp::R_386_GOTPC:
3694 case elfcpp::R_386_16:
3695 case elfcpp::R_386_PC16:
3698 case elfcpp::R_386_8:
3699 case elfcpp::R_386_PC8:
3702 // These are relocations which should only be seen by the
3703 // dynamic linker, and should never be seen here.
3704 case elfcpp::R_386_COPY:
3705 case elfcpp::R_386_GLOB_DAT:
3706 case elfcpp::R_386_JUMP_SLOT:
3707 case elfcpp::R_386_RELATIVE:
3708 case elfcpp::R_386_IRELATIVE:
3709 case elfcpp::R_386_TLS_TPOFF:
3710 case elfcpp::R_386_TLS_DTPMOD32:
3711 case elfcpp::R_386_TLS_DTPOFF32:
3712 case elfcpp::R_386_TLS_TPOFF32:
3713 case elfcpp::R_386_TLS_DESC:
3714 object->error(_("unexpected reloc %u in object file"), r_type);
3717 case elfcpp::R_386_32PLT:
3718 case elfcpp::R_386_TLS_GD_32:
3719 case elfcpp::R_386_TLS_GD_PUSH:
3720 case elfcpp::R_386_TLS_GD_CALL:
3721 case elfcpp::R_386_TLS_GD_POP:
3722 case elfcpp::R_386_TLS_LDM_32:
3723 case elfcpp::R_386_TLS_LDM_PUSH:
3724 case elfcpp::R_386_TLS_LDM_CALL:
3725 case elfcpp::R_386_TLS_LDM_POP:
3726 case elfcpp::R_386_USED_BY_INTEL_200:
3728 object->error(_("unsupported reloc %u in object file"), r_type);
3733 // Scan the relocs during a relocatable link.
3736 Target_i386::scan_relocatable_relocs(Symbol_table* symtab,
3738 Sized_relobj_file<32, false>* object,
3739 unsigned int data_shndx,
3740 unsigned int sh_type,
3741 const unsigned char* prelocs,
3743 Output_section* output_section,
3744 bool needs_special_offset_handling,
3745 size_t local_symbol_count,
3746 const unsigned char* plocal_symbols,
3747 Relocatable_relocs* rr)
3749 typedef gold::Default_scan_relocatable_relocs<Classify_reloc>
3750 Scan_relocatable_relocs;
3752 gold_assert(sh_type == elfcpp::SHT_REL);
3754 gold::scan_relocatable_relocs<32, false, Scan_relocatable_relocs>(
3762 needs_special_offset_handling,
3768 // Scan the relocs for --emit-relocs.
3771 Target_i386::emit_relocs_scan(Symbol_table* symtab,
3773 Sized_relobj_file<32, false>* object,
3774 unsigned int data_shndx,
3775 unsigned int sh_type,
3776 const unsigned char* prelocs,
3778 Output_section* output_section,
3779 bool needs_special_offset_handling,
3780 size_t local_symbol_count,
3781 const unsigned char* plocal_syms,
3782 Relocatable_relocs* rr)
3784 typedef gold::Default_classify_reloc<elfcpp::SHT_REL, 32, false>
3786 typedef gold::Default_emit_relocs_strategy<Classify_reloc>
3787 Emit_relocs_strategy;
3789 gold_assert(sh_type == elfcpp::SHT_REL);
3791 gold::scan_relocatable_relocs<32, false, Emit_relocs_strategy>(
3799 needs_special_offset_handling,
3805 // Emit relocations for a section.
3808 Target_i386::relocate_relocs(
3809 const Relocate_info<32, false>* relinfo,
3810 unsigned int sh_type,
3811 const unsigned char* prelocs,
3813 Output_section* output_section,
3814 elfcpp::Elf_types<32>::Elf_Off offset_in_output_section,
3815 unsigned char* view,
3816 elfcpp::Elf_types<32>::Elf_Addr view_address,
3817 section_size_type view_size,
3818 unsigned char* reloc_view,
3819 section_size_type reloc_view_size)
3821 gold_assert(sh_type == elfcpp::SHT_REL);
3823 gold::relocate_relocs<32, false, Classify_reloc>(
3828 offset_in_output_section,
3836 // Return the value to use for a dynamic which requires special
3837 // treatment. This is how we support equality comparisons of function
3838 // pointers across shared library boundaries, as described in the
3839 // processor specific ABI supplement.
3842 Target_i386::do_dynsym_value(const Symbol* gsym) const
3844 gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset());
3845 return this->plt_address_for_global(gsym);
3848 // Return a string used to fill a code section with nops to take up
3849 // the specified length.
3852 Target_i386::do_code_fill(section_size_type length) const
3856 // Build a jmp instruction to skip over the bytes.
3857 unsigned char jmp[5];
3859 elfcpp::Swap_unaligned<32, false>::writeval(jmp + 1, length - 5);
3860 return (std::string(reinterpret_cast<char*>(&jmp[0]), 5)
3861 + std::string(length - 5, static_cast<char>(0x90)));
3864 // Nop sequences of various lengths.
3865 const char nop1[1] = { '\x90' }; // nop
3866 const char nop2[2] = { '\x66', '\x90' }; // xchg %ax %ax
3867 const char nop3[3] = { '\x8d', '\x76', '\x00' }; // leal 0(%esi),%esi
3868 const char nop4[4] = { '\x8d', '\x74', '\x26', // leal 0(%esi,1),%esi
3870 const char nop5[5] = { '\x90', '\x8d', '\x74', // nop
3871 '\x26', '\x00' }; // leal 0(%esi,1),%esi
3872 const char nop6[6] = { '\x8d', '\xb6', '\x00', // leal 0L(%esi),%esi
3873 '\x00', '\x00', '\x00' };
3874 const char nop7[7] = { '\x8d', '\xb4', '\x26', // leal 0L(%esi,1),%esi
3875 '\x00', '\x00', '\x00',
3877 const char nop8[8] = { '\x90', '\x8d', '\xb4', // nop
3878 '\x26', '\x00', '\x00', // leal 0L(%esi,1),%esi
3880 const char nop9[9] = { '\x89', '\xf6', '\x8d', // movl %esi,%esi
3881 '\xbc', '\x27', '\x00', // leal 0L(%edi,1),%edi
3882 '\x00', '\x00', '\x00' };
3883 const char nop10[10] = { '\x8d', '\x76', '\x00', // leal 0(%esi),%esi
3884 '\x8d', '\xbc', '\x27', // leal 0L(%edi,1),%edi
3885 '\x00', '\x00', '\x00',
3887 const char nop11[11] = { '\x8d', '\x74', '\x26', // leal 0(%esi,1),%esi
3888 '\x00', '\x8d', '\xbc', // leal 0L(%edi,1),%edi
3889 '\x27', '\x00', '\x00',
3891 const char nop12[12] = { '\x8d', '\xb6', '\x00', // leal 0L(%esi),%esi
3892 '\x00', '\x00', '\x00', // leal 0L(%edi),%edi
3893 '\x8d', '\xbf', '\x00',
3894 '\x00', '\x00', '\x00' };
3895 const char nop13[13] = { '\x8d', '\xb6', '\x00', // leal 0L(%esi),%esi
3896 '\x00', '\x00', '\x00', // leal 0L(%edi,1),%edi
3897 '\x8d', '\xbc', '\x27',
3898 '\x00', '\x00', '\x00',
3900 const char nop14[14] = { '\x8d', '\xb4', '\x26', // leal 0L(%esi,1),%esi
3901 '\x00', '\x00', '\x00', // leal 0L(%edi,1),%edi
3902 '\x00', '\x8d', '\xbc',
3903 '\x27', '\x00', '\x00',
3905 const char nop15[15] = { '\xeb', '\x0d', '\x90', // jmp .+15
3906 '\x90', '\x90', '\x90', // nop,nop,nop,...
3907 '\x90', '\x90', '\x90',
3908 '\x90', '\x90', '\x90',
3909 '\x90', '\x90', '\x90' };
3911 const char* nops[16] = {
3913 nop1, nop2, nop3, nop4, nop5, nop6, nop7,
3914 nop8, nop9, nop10, nop11, nop12, nop13, nop14, nop15
3917 return std::string(nops[length], length);
3920 // Return the value to use for the base of a DW_EH_PE_datarel offset
3921 // in an FDE. Solaris and SVR4 use DW_EH_PE_datarel because their
3922 // assembler can not write out the difference between two labels in
3923 // different sections, so instead of using a pc-relative value they
3924 // use an offset from the GOT.
3927 Target_i386::do_ehframe_datarel_base() const
3929 gold_assert(this->global_offset_table_ != NULL);
3930 Symbol* sym = this->global_offset_table_;
3931 Sized_symbol<32>* ssym = static_cast<Sized_symbol<32>*>(sym);
3932 return ssym->value();
3935 // Return whether SYM should be treated as a call to a non-split
3936 // function. We don't want that to be true of a call to a
3937 // get_pc_thunk function.
3940 Target_i386::do_is_call_to_non_split(const Symbol* sym,
3941 const unsigned char*,
3942 const unsigned char*,
3943 section_size_type) const
3945 return (sym->type() == elfcpp::STT_FUNC
3946 && !is_prefix_of("__i686.get_pc_thunk.", sym->name()));
3949 // FNOFFSET in section SHNDX in OBJECT is the start of a function
3950 // compiled with -fsplit-stack. The function calls non-split-stack
3951 // code. We have to change the function so that it always ensures
3952 // that it has enough stack space to run some random function.
3955 Target_i386::do_calls_non_split(Relobj* object, unsigned int shndx,
3956 section_offset_type fnoffset,
3957 section_size_type fnsize,
3958 const unsigned char*,
3960 unsigned char* view,
3961 section_size_type view_size,
3963 std::string* to) const
3965 // The function starts with a comparison of the stack pointer and a
3966 // field in the TCB. This is followed by a jump.
3969 if (this->match_view(view, view_size, fnoffset, "\x65\x3b\x25", 3)
3972 // We will call __morestack if the carry flag is set after this
3973 // comparison. We turn the comparison into an stc instruction
3975 view[fnoffset] = '\xf9';
3976 this->set_view_to_nop(view, view_size, fnoffset + 1, 6);
3978 // lea NN(%esp),%ecx
3979 // lea NN(%esp),%edx
3980 else if ((this->match_view(view, view_size, fnoffset, "\x8d\x8c\x24", 3)
3981 || this->match_view(view, view_size, fnoffset, "\x8d\x94\x24", 3))
3984 // This is loading an offset from the stack pointer for a
3985 // comparison. The offset is negative, so we decrease the
3986 // offset by the amount of space we need for the stack. This
3987 // means we will avoid calling __morestack if there happens to
3988 // be plenty of space on the stack already.
3989 unsigned char* pval = view + fnoffset + 3;
3990 uint32_t val = elfcpp::Swap_unaligned<32, false>::readval(pval);
3991 val -= parameters->options().split_stack_adjust_size();
3992 elfcpp::Swap_unaligned<32, false>::writeval(pval, val);
3996 if (!object->has_no_split_stack())
3997 object->error(_("failed to match split-stack sequence at "
3998 "section %u offset %0zx"),
3999 shndx, static_cast<size_t>(fnoffset));
4003 // We have to change the function so that it calls
4004 // __morestack_non_split instead of __morestack. The former will
4005 // allocate additional stack space.
4006 *from = "__morestack";
4007 *to = "__morestack_non_split";
4010 // The selector for i386 object files. Note this is never instantiated
4011 // directly. It's only used in Target_selector_i386_nacl, below.
4013 class Target_selector_i386 : public Target_selector_freebsd
4016 Target_selector_i386()
4017 : Target_selector_freebsd(elfcpp::EM_386, 32, false,
4018 "elf32-i386", "elf32-i386-freebsd",
4023 do_instantiate_target()
4024 { return new Target_i386(); }
4027 // NaCl variant. It uses different PLT contents.
4029 class Output_data_plt_i386_nacl : public Output_data_plt_i386
4032 Output_data_plt_i386_nacl(Layout* layout,
4033 Output_data_got_plt_i386* got_plt,
4034 Output_data_space* got_irelative)
4035 : Output_data_plt_i386(layout, plt_entry_size, got_plt, got_irelative)
4039 virtual unsigned int
4040 do_get_plt_entry_size() const
4041 { return plt_entry_size; }
4044 do_add_eh_frame(Layout* layout)
4046 layout->add_eh_frame_for_plt(this, plt_eh_frame_cie, plt_eh_frame_cie_size,
4047 plt_eh_frame_fde, plt_eh_frame_fde_size);
4050 // The size of an entry in the PLT.
4051 static const int plt_entry_size = 64;
4053 // The .eh_frame unwind information for the PLT.
4054 static const int plt_eh_frame_fde_size = 32;
4055 static const unsigned char plt_eh_frame_fde[plt_eh_frame_fde_size];
4058 class Output_data_plt_i386_nacl_exec : public Output_data_plt_i386_nacl
4061 Output_data_plt_i386_nacl_exec(Layout* layout,
4062 Output_data_got_plt_i386* got_plt,
4063 Output_data_space* got_irelative)
4064 : Output_data_plt_i386_nacl(layout, got_plt, got_irelative)
4069 do_fill_first_plt_entry(unsigned char* pov,
4070 elfcpp::Elf_types<32>::Elf_Addr got_address);
4072 virtual unsigned int
4073 do_fill_plt_entry(unsigned char* pov,
4074 elfcpp::Elf_types<32>::Elf_Addr got_address,
4075 unsigned int got_offset,
4076 unsigned int plt_offset,
4077 unsigned int plt_rel_offset);
4080 // The first entry in the PLT for an executable.
4081 static const unsigned char first_plt_entry[plt_entry_size];
4083 // Other entries in the PLT for an executable.
4084 static const unsigned char plt_entry[plt_entry_size];
4087 class Output_data_plt_i386_nacl_dyn : public Output_data_plt_i386_nacl
4090 Output_data_plt_i386_nacl_dyn(Layout* layout,
4091 Output_data_got_plt_i386* got_plt,
4092 Output_data_space* got_irelative)
4093 : Output_data_plt_i386_nacl(layout, got_plt, got_irelative)
4098 do_fill_first_plt_entry(unsigned char* pov, elfcpp::Elf_types<32>::Elf_Addr);
4100 virtual unsigned int
4101 do_fill_plt_entry(unsigned char* pov,
4102 elfcpp::Elf_types<32>::Elf_Addr,
4103 unsigned int got_offset,
4104 unsigned int plt_offset,
4105 unsigned int plt_rel_offset);
4108 // The first entry in the PLT for a shared object.
4109 static const unsigned char first_plt_entry[plt_entry_size];
4111 // Other entries in the PLT for a shared object.
4112 static const unsigned char plt_entry[plt_entry_size];
4115 class Target_i386_nacl : public Target_i386
4119 : Target_i386(&i386_nacl_info)
4123 virtual Output_data_plt_i386*
4124 do_make_data_plt(Layout* layout,
4125 Output_data_got_plt_i386* got_plt,
4126 Output_data_space* got_irelative,
4130 return new Output_data_plt_i386_nacl_dyn(layout, got_plt, got_irelative);
4132 return new Output_data_plt_i386_nacl_exec(layout, got_plt, got_irelative);
4136 do_code_fill(section_size_type length) const;
4139 static const Target::Target_info i386_nacl_info;
4142 const Target::Target_info Target_i386_nacl::i386_nacl_info =
4145 false, // is_big_endian
4146 elfcpp::EM_386, // machine_code
4147 false, // has_make_symbol
4148 false, // has_resolve
4149 true, // has_code_fill
4150 true, // is_default_stack_executable
4151 true, // can_icf_inline_merge_sections
4153 "/lib/ld-nacl-x86-32.so.1", // dynamic_linker
4154 0x20000, // default_text_segment_address
4155 0x10000, // abi_pagesize (overridable by -z max-page-size)
4156 0x10000, // common_pagesize (overridable by -z common-page-size)
4157 true, // isolate_execinstr
4158 0x10000000, // rosegment_gap
4159 elfcpp::SHN_UNDEF, // small_common_shndx
4160 elfcpp::SHN_UNDEF, // large_common_shndx
4161 0, // small_common_section_flags
4162 0, // large_common_section_flags
4163 NULL, // attributes_section
4164 NULL, // attributes_vendor
4165 "_start", // entry_symbol_name
4166 32, // hash_entry_size
4169 #define NACLMASK 0xe0 // 32-byte alignment mask
4172 Output_data_plt_i386_nacl_exec::first_plt_entry[plt_entry_size] =
4174 0xff, 0x35, // pushl contents of memory address
4175 0, 0, 0, 0, // replaced with address of .got + 4
4176 0x8b, 0x0d, // movl contents of address, %ecx
4177 0, 0, 0, 0, // replaced with address of .got + 8
4178 0x83, 0xe1, NACLMASK, // andl $NACLMASK, %ecx
4179 0xff, 0xe1, // jmp *%ecx
4180 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4181 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4182 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4183 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4184 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4185 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4186 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4187 0x90, 0x90, 0x90, 0x90, 0x90
4191 Output_data_plt_i386_nacl_exec::do_fill_first_plt_entry(
4193 elfcpp::Elf_types<32>::Elf_Addr got_address)
4195 memcpy(pov, first_plt_entry, plt_entry_size);
4196 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_address + 4);
4197 elfcpp::Swap<32, false>::writeval(pov + 8, got_address + 8);
4200 // The first entry in the PLT for a shared object.
4203 Output_data_plt_i386_nacl_dyn::first_plt_entry[plt_entry_size] =
4205 0xff, 0xb3, 4, 0, 0, 0, // pushl 4(%ebx)
4206 0x8b, 0x4b, 0x08, // mov 0x8(%ebx), %ecx
4207 0x83, 0xe1, NACLMASK, // andl $NACLMASK, %ecx
4208 0xff, 0xe1, // jmp *%ecx
4209 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4210 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4211 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4212 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4213 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4214 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4215 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4216 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4217 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4218 0x90, 0x90, 0x90, 0x90, 0x90 // nops
4222 Output_data_plt_i386_nacl_dyn::do_fill_first_plt_entry(
4224 elfcpp::Elf_types<32>::Elf_Addr)
4226 memcpy(pov, first_plt_entry, plt_entry_size);
4229 // Subsequent entries in the PLT for an executable.
4232 Output_data_plt_i386_nacl_exec::plt_entry[plt_entry_size] =
4234 0x8b, 0x0d, // movl contents of address, %ecx */
4235 0, 0, 0, 0, // replaced with address of symbol in .got
4236 0x83, 0xe1, NACLMASK, // andl $NACLMASK, %ecx
4237 0xff, 0xe1, // jmp *%ecx
4239 // Pad to the next 32-byte boundary with nop instructions.
4241 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4242 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4244 // Lazy GOT entries point here (32-byte aligned).
4245 0x68, // pushl immediate
4246 0, 0, 0, 0, // replaced with offset into relocation table
4247 0xe9, // jmp relative
4248 0, 0, 0, 0, // replaced with offset to start of .plt
4250 // Pad to the next 32-byte boundary with nop instructions.
4251 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4252 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4257 Output_data_plt_i386_nacl_exec::do_fill_plt_entry(
4259 elfcpp::Elf_types<32>::Elf_Addr got_address,
4260 unsigned int got_offset,
4261 unsigned int plt_offset,
4262 unsigned int plt_rel_offset)
4264 memcpy(pov, plt_entry, plt_entry_size);
4265 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
4266 got_address + got_offset);
4267 elfcpp::Swap_unaligned<32, false>::writeval(pov + 33, plt_rel_offset);
4268 elfcpp::Swap<32, false>::writeval(pov + 38, - (plt_offset + 38 + 4));
4272 // Subsequent entries in the PLT for a shared object.
4275 Output_data_plt_i386_nacl_dyn::plt_entry[plt_entry_size] =
4277 0x8b, 0x8b, // movl offset(%ebx), %ecx
4278 0, 0, 0, 0, // replaced with offset of symbol in .got
4279 0x83, 0xe1, 0xe0, // andl $NACLMASK, %ecx
4280 0xff, 0xe1, // jmp *%ecx
4282 // Pad to the next 32-byte boundary with nop instructions.
4284 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4285 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4287 // Lazy GOT entries point here (32-byte aligned).
4288 0x68, // pushl immediate
4289 0, 0, 0, 0, // replaced with offset into relocation table.
4290 0xe9, // jmp relative
4291 0, 0, 0, 0, // replaced with offset to start of .plt.
4293 // Pad to the next 32-byte boundary with nop instructions.
4294 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4295 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4300 Output_data_plt_i386_nacl_dyn::do_fill_plt_entry(
4302 elfcpp::Elf_types<32>::Elf_Addr,
4303 unsigned int got_offset,
4304 unsigned int plt_offset,
4305 unsigned int plt_rel_offset)
4307 memcpy(pov, plt_entry, plt_entry_size);
4308 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_offset);
4309 elfcpp::Swap_unaligned<32, false>::writeval(pov + 33, plt_rel_offset);
4310 elfcpp::Swap<32, false>::writeval(pov + 38, - (plt_offset + 38 + 4));
4315 Output_data_plt_i386_nacl::plt_eh_frame_fde[plt_eh_frame_fde_size] =
4317 0, 0, 0, 0, // Replaced with offset to .plt.
4318 0, 0, 0, 0, // Replaced with size of .plt.
4319 0, // Augmentation size.
4320 elfcpp::DW_CFA_def_cfa_offset, 8, // DW_CFA_def_cfa_offset: 8.
4321 elfcpp::DW_CFA_advance_loc + 6, // Advance 6 to __PLT__ + 6.
4322 elfcpp::DW_CFA_def_cfa_offset, 12, // DW_CFA_def_cfa_offset: 12.
4323 elfcpp::DW_CFA_advance_loc + 58, // Advance 58 to __PLT__ + 64.
4324 elfcpp::DW_CFA_def_cfa_expression, // DW_CFA_def_cfa_expression.
4325 13, // Block length.
4326 elfcpp::DW_OP_breg4, 4, // Push %esp + 4.
4327 elfcpp::DW_OP_breg8, 0, // Push %eip.
4328 elfcpp::DW_OP_const1u, 63, // Push 0x3f.
4329 elfcpp::DW_OP_and, // & (%eip & 0x3f).
4330 elfcpp::DW_OP_const1u, 37, // Push 0x25.
4331 elfcpp::DW_OP_ge, // >= ((%eip & 0x3f) >= 0x25)
4332 elfcpp::DW_OP_lit2, // Push 2.
4333 elfcpp::DW_OP_shl, // << (((%eip & 0x3f) >= 0x25) << 2)
4334 elfcpp::DW_OP_plus, // + ((((%eip&0x3f)>=0x25)<<2)+%esp+4
4335 elfcpp::DW_CFA_nop, // Align to 32 bytes.
4339 // Return a string used to fill a code section with nops.
4340 // For NaCl, long NOPs are only valid if they do not cross
4341 // bundle alignment boundaries, so keep it simple with one-byte NOPs.
4343 Target_i386_nacl::do_code_fill(section_size_type length) const
4345 return std::string(length, static_cast<char>(0x90));
4348 // The selector for i386-nacl object files.
4350 class Target_selector_i386_nacl
4351 : public Target_selector_nacl<Target_selector_i386, Target_i386_nacl>
4354 Target_selector_i386_nacl()
4355 : Target_selector_nacl<Target_selector_i386,
4356 Target_i386_nacl>("x86-32",
4362 Target_selector_i386_nacl target_selector_i386;
4364 // IAMCU variant. It uses EM_IAMCU, not EM_386.
4366 class Target_iamcu : public Target_i386
4370 : Target_i386(&iamcu_info)
4374 // Information about this specific target which we pass to the
4375 // general Target structure.
4376 static const Target::Target_info iamcu_info;
4379 const Target::Target_info Target_iamcu::iamcu_info =
4382 false, // is_big_endian
4383 elfcpp::EM_IAMCU, // machine_code
4384 false, // has_make_symbol
4385 false, // has_resolve
4386 true, // has_code_fill
4387 true, // is_default_stack_executable
4388 true, // can_icf_inline_merge_sections
4390 "/usr/lib/libc.so.1", // dynamic_linker
4391 0x08048000, // default_text_segment_address
4392 0x1000, // abi_pagesize (overridable by -z max-page-size)
4393 0x1000, // common_pagesize (overridable by -z common-page-size)
4394 false, // isolate_execinstr
4396 elfcpp::SHN_UNDEF, // small_common_shndx
4397 elfcpp::SHN_UNDEF, // large_common_shndx
4398 0, // small_common_section_flags
4399 0, // large_common_section_flags
4400 NULL, // attributes_section
4401 NULL, // attributes_vendor
4402 "_start", // entry_symbol_name
4403 32, // hash_entry_size
4406 class Target_selector_iamcu : public Target_selector
4409 Target_selector_iamcu()
4410 : Target_selector(elfcpp::EM_IAMCU, 32, false, "elf32-iamcu",
4415 do_instantiate_target()
4416 { return new Target_iamcu(); }
4419 Target_selector_iamcu target_selector_iamcu;
4421 } // End anonymous namespace.