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*) const;
505 // Adjust -fsplit-stack code which calls non-split-stack code.
507 do_calls_non_split(Relobj* object, unsigned int shndx,
508 section_offset_type fnoffset, section_size_type fnsize,
509 const unsigned char* prelocs, size_t reloc_count,
510 unsigned char* view, section_size_type view_size,
511 std::string* from, std::string* to) const;
513 // Return the size of the GOT section.
517 gold_assert(this->got_ != NULL);
518 return this->got_->data_size();
521 // Return the number of entries in the GOT.
523 got_entry_count() const
525 if (this->got_ == NULL)
527 return this->got_size() / 4;
530 // Return the number of entries in the PLT.
532 plt_entry_count() const;
534 // Return the offset of the first non-reserved PLT entry.
536 first_plt_entry_offset() const;
538 // Return the size of each PLT entry.
540 plt_entry_size() const;
543 // Instantiate the plt_ member.
544 // This chooses the right PLT flavor for an executable or a shared object.
545 Output_data_plt_i386*
546 make_data_plt(Layout* layout,
547 Output_data_got_plt_i386* got_plt,
548 Output_data_space* got_irelative,
550 { return this->do_make_data_plt(layout, got_plt, got_irelative, dyn); }
552 virtual Output_data_plt_i386*
553 do_make_data_plt(Layout* layout,
554 Output_data_got_plt_i386* got_plt,
555 Output_data_space* got_irelative,
559 return new Output_data_plt_i386_dyn(layout, got_plt, got_irelative);
561 return new Output_data_plt_i386_exec(layout, got_plt, got_irelative);
565 // The class which scans relocations.
570 get_reference_flags(unsigned int r_type);
573 local(Symbol_table* symtab, Layout* layout, Target_i386* target,
574 Sized_relobj_file<32, false>* object,
575 unsigned int data_shndx,
576 Output_section* output_section,
577 const elfcpp::Rel<32, false>& reloc, unsigned int r_type,
578 const elfcpp::Sym<32, false>& lsym,
582 global(Symbol_table* symtab, Layout* layout, Target_i386* target,
583 Sized_relobj_file<32, false>* object,
584 unsigned int data_shndx,
585 Output_section* output_section,
586 const elfcpp::Rel<32, false>& reloc, unsigned int r_type,
590 local_reloc_may_be_function_pointer(Symbol_table* symtab, Layout* layout,
592 Sized_relobj_file<32, false>* object,
593 unsigned int data_shndx,
594 Output_section* output_section,
595 const elfcpp::Rel<32, false>& reloc,
597 const elfcpp::Sym<32, false>& lsym);
600 global_reloc_may_be_function_pointer(Symbol_table* symtab, Layout* layout,
602 Sized_relobj_file<32, false>* object,
603 unsigned int data_shndx,
604 Output_section* output_section,
605 const elfcpp::Rel<32, false>& reloc,
610 possible_function_pointer_reloc(unsigned int r_type);
613 reloc_needs_plt_for_ifunc(Sized_relobj_file<32, false>*,
614 unsigned int r_type);
617 unsupported_reloc_local(Sized_relobj_file<32, false>*, unsigned int r_type);
620 unsupported_reloc_global(Sized_relobj_file<32, false>*, unsigned int r_type,
624 // The class which implements relocation.
629 : skip_call_tls_get_addr_(false),
630 local_dynamic_type_(LOCAL_DYNAMIC_NONE)
635 if (this->skip_call_tls_get_addr_)
637 // FIXME: This needs to specify the location somehow.
638 gold_error(_("missing expected TLS relocation"));
642 // Return whether the static relocation needs to be applied.
644 should_apply_static_reloc(const Sized_symbol<32>* gsym,
647 Output_section* output_section);
649 // Do a relocation. Return false if the caller should not issue
650 // any warnings about this relocation.
652 relocate(const Relocate_info<32, false>*, unsigned int,
653 Target_i386*, Output_section*, size_t, const unsigned char*,
654 const Sized_symbol<32>*, const Symbol_value<32>*,
655 unsigned char*, elfcpp::Elf_types<32>::Elf_Addr,
659 // Do a TLS relocation.
661 relocate_tls(const Relocate_info<32, false>*, Target_i386* target,
662 size_t relnum, const elfcpp::Rel<32, false>&,
663 unsigned int r_type, const Sized_symbol<32>*,
664 const Symbol_value<32>*,
665 unsigned char*, elfcpp::Elf_types<32>::Elf_Addr,
668 // Do a TLS General-Dynamic to Initial-Exec transition.
670 tls_gd_to_ie(const Relocate_info<32, false>*, size_t relnum,
671 const elfcpp::Rel<32, false>&, unsigned int r_type,
672 elfcpp::Elf_types<32>::Elf_Addr value,
674 section_size_type view_size);
676 // Do a TLS General-Dynamic to Local-Exec transition.
678 tls_gd_to_le(const Relocate_info<32, false>*, size_t relnum,
679 Output_segment* tls_segment,
680 const elfcpp::Rel<32, false>&, unsigned int r_type,
681 elfcpp::Elf_types<32>::Elf_Addr value,
683 section_size_type view_size);
685 // Do a TLS_GOTDESC or TLS_DESC_CALL General-Dynamic to Initial-Exec
688 tls_desc_gd_to_ie(const Relocate_info<32, false>*, size_t relnum,
689 const elfcpp::Rel<32, false>&, unsigned int r_type,
690 elfcpp::Elf_types<32>::Elf_Addr value,
692 section_size_type view_size);
694 // Do a TLS_GOTDESC or TLS_DESC_CALL General-Dynamic to Local-Exec
697 tls_desc_gd_to_le(const Relocate_info<32, false>*, size_t relnum,
698 Output_segment* tls_segment,
699 const elfcpp::Rel<32, false>&, unsigned int r_type,
700 elfcpp::Elf_types<32>::Elf_Addr value,
702 section_size_type view_size);
704 // Do a TLS Local-Dynamic to Local-Exec transition.
706 tls_ld_to_le(const Relocate_info<32, false>*, size_t relnum,
707 Output_segment* tls_segment,
708 const elfcpp::Rel<32, false>&, unsigned int r_type,
709 elfcpp::Elf_types<32>::Elf_Addr value,
711 section_size_type view_size);
713 // Do a TLS Initial-Exec to Local-Exec transition.
715 tls_ie_to_le(const Relocate_info<32, false>*, size_t relnum,
716 Output_segment* tls_segment,
717 const elfcpp::Rel<32, false>&, unsigned int r_type,
718 elfcpp::Elf_types<32>::Elf_Addr value,
720 section_size_type view_size);
722 // We need to keep track of which type of local dynamic relocation
723 // we have seen, so that we can optimize R_386_TLS_LDO_32 correctly.
724 enum Local_dynamic_type
731 // This is set if we should skip the next reloc, which should be a
732 // PLT32 reloc against ___tls_get_addr.
733 bool skip_call_tls_get_addr_;
734 // The type of local dynamic relocation we have seen in the section
735 // being relocated, if any.
736 Local_dynamic_type local_dynamic_type_;
739 // A class for inquiring about properties of a relocation,
740 // used while scanning relocs during a relocatable link and
741 // garbage collection.
742 class Classify_reloc :
743 public gold::Default_classify_reloc<elfcpp::SHT_REL, 32, false>
746 typedef Reloc_types<elfcpp::SHT_REL, 32, false>::Reloc Reltype;
748 // Return the explicit addend of the relocation (return 0 for SHT_REL).
749 static elfcpp::Elf_types<32>::Elf_Swxword
750 get_r_addend(const Reltype*)
753 // Return the size of the addend of the relocation (only used for SHT_REL).
755 get_size_for_reloc(unsigned int, Relobj*);
758 // Adjust TLS relocation type based on the options and whether this
759 // is a local symbol.
760 static tls::Tls_optimization
761 optimize_tls_reloc(bool is_final, int r_type);
763 // Check if relocation against this symbol is a candidate for
765 // mov foo@GOT(%reg), %reg
767 // lea foo@GOTOFF(%reg), %reg.
769 can_convert_mov_to_lea(const Symbol* gsym)
771 gold_assert(gsym != NULL);
772 return (gsym->type() != elfcpp::STT_GNU_IFUNC
773 && !gsym->is_undefined ()
774 && !gsym->is_from_dynobj()
775 && !gsym->is_preemptible()
776 && (!parameters->options().shared()
777 || (gsym->visibility() != elfcpp::STV_DEFAULT
778 && gsym->visibility() != elfcpp::STV_PROTECTED)
779 || parameters->options().Bsymbolic())
780 && strcmp(gsym->name(), "_DYNAMIC") != 0);
783 // Get the GOT section, creating it if necessary.
784 Output_data_got<32, false>*
785 got_section(Symbol_table*, Layout*);
787 // Get the GOT PLT section.
788 Output_data_got_plt_i386*
789 got_plt_section() const
791 gold_assert(this->got_plt_ != NULL);
792 return this->got_plt_;
795 // Get the GOT section for TLSDESC entries.
796 Output_data_got<32, false>*
797 got_tlsdesc_section() const
799 gold_assert(this->got_tlsdesc_ != NULL);
800 return this->got_tlsdesc_;
803 // Create the PLT section.
805 make_plt_section(Symbol_table* symtab, Layout* layout);
807 // Create a PLT entry for a global symbol.
809 make_plt_entry(Symbol_table*, Layout*, Symbol*);
811 // Create a PLT entry for a local STT_GNU_IFUNC symbol.
813 make_local_ifunc_plt_entry(Symbol_table*, Layout*,
814 Sized_relobj_file<32, false>* relobj,
815 unsigned int local_sym_index);
817 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
819 define_tls_base_symbol(Symbol_table*, Layout*);
821 // Create a GOT entry for the TLS module index.
823 got_mod_index_entry(Symbol_table* symtab, Layout* layout,
824 Sized_relobj_file<32, false>* object);
826 // Get the PLT section.
827 Output_data_plt_i386*
830 gold_assert(this->plt_ != NULL);
834 // Get the dynamic reloc section, creating it if necessary.
836 rel_dyn_section(Layout*);
838 // Get the section to use for TLS_DESC relocations.
840 rel_tls_desc_section(Layout*) const;
842 // Get the section to use for IRELATIVE relocations.
844 rel_irelative_section(Layout*);
846 // Add a potential copy relocation.
848 copy_reloc(Symbol_table* symtab, Layout* layout,
849 Sized_relobj_file<32, false>* object,
850 unsigned int shndx, Output_section* output_section,
851 Symbol* sym, const elfcpp::Rel<32, false>& reloc)
853 unsigned int r_type = elfcpp::elf_r_type<32>(reloc.get_r_info());
854 this->copy_relocs_.copy_reloc(symtab, layout,
855 symtab->get_sized_symbol<32>(sym),
856 object, shndx, output_section,
857 r_type, reloc.get_r_offset(), 0,
858 this->rel_dyn_section(layout));
861 // Information about this specific target which we pass to the
862 // general Target structure.
863 static const Target::Target_info i386_info;
865 // The types of GOT entries needed for this platform.
866 // These values are exposed to the ABI in an incremental link.
867 // Do not renumber existing values without changing the version
868 // number of the .gnu_incremental_inputs section.
871 GOT_TYPE_STANDARD = 0, // GOT entry for a regular symbol
872 GOT_TYPE_TLS_NOFFSET = 1, // GOT entry for negative TLS offset
873 GOT_TYPE_TLS_OFFSET = 2, // GOT entry for positive TLS offset
874 GOT_TYPE_TLS_PAIR = 3, // GOT entry for TLS module/offset pair
875 GOT_TYPE_TLS_DESC = 4 // GOT entry for TLS_DESC pair
879 Output_data_got<32, false>* got_;
881 Output_data_plt_i386* plt_;
882 // The GOT PLT section.
883 Output_data_got_plt_i386* got_plt_;
884 // The GOT section for IRELATIVE relocations.
885 Output_data_space* got_irelative_;
886 // The GOT section for TLSDESC relocations.
887 Output_data_got<32, false>* got_tlsdesc_;
888 // The _GLOBAL_OFFSET_TABLE_ symbol.
889 Symbol* global_offset_table_;
890 // The dynamic reloc section.
891 Reloc_section* rel_dyn_;
892 // The section to use for IRELATIVE relocs.
893 Reloc_section* rel_irelative_;
894 // Relocs saved to avoid a COPY reloc.
895 Copy_relocs<elfcpp::SHT_REL, 32, false> copy_relocs_;
896 // Offset of the GOT entry for the TLS module index.
897 unsigned int got_mod_index_offset_;
898 // True if the _TLS_MODULE_BASE_ symbol has been defined.
899 bool tls_base_symbol_defined_;
902 const Target::Target_info Target_i386::i386_info =
905 false, // is_big_endian
906 elfcpp::EM_386, // machine_code
907 false, // has_make_symbol
908 false, // has_resolve
909 true, // has_code_fill
910 true, // is_default_stack_executable
911 true, // can_icf_inline_merge_sections
913 "/usr/lib/libc.so.1", // dynamic_linker
914 0x08048000, // default_text_segment_address
915 0x1000, // abi_pagesize (overridable by -z max-page-size)
916 0x1000, // common_pagesize (overridable by -z common-page-size)
917 false, // isolate_execinstr
919 elfcpp::SHN_UNDEF, // small_common_shndx
920 elfcpp::SHN_UNDEF, // large_common_shndx
921 0, // small_common_section_flags
922 0, // large_common_section_flags
923 NULL, // attributes_section
924 NULL, // attributes_vendor
925 "_start", // entry_symbol_name
926 32, // hash_entry_size
929 // Get the GOT section, creating it if necessary.
931 Output_data_got<32, false>*
932 Target_i386::got_section(Symbol_table* symtab, Layout* layout)
934 if (this->got_ == NULL)
936 gold_assert(symtab != NULL && layout != NULL);
938 this->got_ = new Output_data_got<32, false>();
940 // When using -z now, we can treat .got.plt as a relro section.
941 // Without -z now, it is modified after program startup by lazy
943 bool is_got_plt_relro = parameters->options().now();
944 Output_section_order got_order = (is_got_plt_relro
947 Output_section_order got_plt_order = (is_got_plt_relro
949 : ORDER_NON_RELRO_FIRST);
951 layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
953 | elfcpp::SHF_WRITE),
954 this->got_, got_order, true);
956 this->got_plt_ = new Output_data_got_plt_i386(layout);
957 layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
959 | elfcpp::SHF_WRITE),
960 this->got_plt_, got_plt_order,
963 // The first three entries are reserved.
964 this->got_plt_->set_current_data_size(3 * 4);
966 if (!is_got_plt_relro)
968 // Those bytes can go into the relro segment.
969 layout->increase_relro(3 * 4);
972 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
973 this->global_offset_table_ =
974 symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
975 Symbol_table::PREDEFINED,
977 0, 0, elfcpp::STT_OBJECT,
979 elfcpp::STV_HIDDEN, 0,
982 // If there are any IRELATIVE relocations, they get GOT entries
983 // in .got.plt after the jump slot relocations.
984 this->got_irelative_ = new Output_data_space(4, "** GOT IRELATIVE PLT");
985 layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
987 | elfcpp::SHF_WRITE),
988 this->got_irelative_,
989 got_plt_order, is_got_plt_relro);
991 // If there are any TLSDESC relocations, they get GOT entries in
992 // .got.plt after the jump slot entries.
993 this->got_tlsdesc_ = new Output_data_got<32, false>();
994 layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
996 | elfcpp::SHF_WRITE),
998 got_plt_order, is_got_plt_relro);
1004 // Get the dynamic reloc section, creating it if necessary.
1006 Target_i386::Reloc_section*
1007 Target_i386::rel_dyn_section(Layout* layout)
1009 if (this->rel_dyn_ == NULL)
1011 gold_assert(layout != NULL);
1012 this->rel_dyn_ = new Reloc_section(parameters->options().combreloc());
1013 layout->add_output_section_data(".rel.dyn", elfcpp::SHT_REL,
1014 elfcpp::SHF_ALLOC, this->rel_dyn_,
1015 ORDER_DYNAMIC_RELOCS, false);
1017 return this->rel_dyn_;
1020 // Get the section to use for IRELATIVE relocs, creating it if
1021 // necessary. These go in .rel.dyn, but only after all other dynamic
1022 // relocations. They need to follow the other dynamic relocations so
1023 // that they can refer to global variables initialized by those
1026 Target_i386::Reloc_section*
1027 Target_i386::rel_irelative_section(Layout* layout)
1029 if (this->rel_irelative_ == NULL)
1031 // Make sure we have already create the dynamic reloc section.
1032 this->rel_dyn_section(layout);
1033 this->rel_irelative_ = new Reloc_section(false);
1034 layout->add_output_section_data(".rel.dyn", elfcpp::SHT_REL,
1035 elfcpp::SHF_ALLOC, this->rel_irelative_,
1036 ORDER_DYNAMIC_RELOCS, false);
1037 gold_assert(this->rel_dyn_->output_section()
1038 == this->rel_irelative_->output_section());
1040 return this->rel_irelative_;
1043 // Write the first three reserved words of the .got.plt section.
1044 // The remainder of the section is written while writing the PLT
1045 // in Output_data_plt_i386::do_write.
1048 Output_data_got_plt_i386::do_write(Output_file* of)
1050 // The first entry in the GOT is the address of the .dynamic section
1051 // aka the PT_DYNAMIC segment. The next two entries are reserved.
1052 // We saved space for them when we created the section in
1053 // Target_i386::got_section.
1054 const off_t got_file_offset = this->offset();
1055 gold_assert(this->data_size() >= 12);
1056 unsigned char* const got_view = of->get_output_view(got_file_offset, 12);
1057 Output_section* dynamic = this->layout_->dynamic_section();
1058 uint32_t dynamic_addr = dynamic == NULL ? 0 : dynamic->address();
1059 elfcpp::Swap<32, false>::writeval(got_view, dynamic_addr);
1060 memset(got_view + 4, 0, 8);
1061 of->write_output_view(got_file_offset, 12, got_view);
1064 // Create the PLT section. The ordinary .got section is an argument,
1065 // since we need to refer to the start. We also create our own .got
1066 // section just for PLT entries.
1068 Output_data_plt_i386::Output_data_plt_i386(Layout* layout,
1070 Output_data_got_plt_i386* got_plt,
1071 Output_data_space* got_irelative)
1072 : Output_section_data(addralign),
1073 tls_desc_rel_(NULL), irelative_rel_(NULL), got_plt_(got_plt),
1074 got_irelative_(got_irelative), count_(0), irelative_count_(0),
1075 global_ifuncs_(), local_ifuncs_()
1077 this->rel_ = new Reloc_section(false);
1078 layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL,
1079 elfcpp::SHF_ALLOC, this->rel_,
1080 ORDER_DYNAMIC_PLT_RELOCS, false);
1084 Output_data_plt_i386::do_adjust_output_section(Output_section* os)
1086 // UnixWare sets the entsize of .plt to 4, and so does the old GNU
1087 // linker, and so do we.
1091 // Add an entry to the PLT.
1094 Output_data_plt_i386::add_entry(Symbol_table* symtab, Layout* layout,
1097 gold_assert(!gsym->has_plt_offset());
1099 // Every PLT entry needs a reloc.
1100 if (gsym->type() == elfcpp::STT_GNU_IFUNC
1101 && gsym->can_use_relative_reloc(false))
1103 gsym->set_plt_offset(this->irelative_count_ * this->get_plt_entry_size());
1104 ++this->irelative_count_;
1105 section_offset_type got_offset =
1106 this->got_irelative_->current_data_size();
1107 this->got_irelative_->set_current_data_size(got_offset + 4);
1108 Reloc_section* rel = this->rel_irelative(symtab, layout);
1109 rel->add_symbolless_global_addend(gsym, elfcpp::R_386_IRELATIVE,
1110 this->got_irelative_, got_offset);
1111 struct Global_ifunc gi;
1113 gi.got_offset = got_offset;
1114 this->global_ifuncs_.push_back(gi);
1118 // When setting the PLT offset we skip the initial reserved PLT
1120 gsym->set_plt_offset((this->count_ + 1) * this->get_plt_entry_size());
1124 section_offset_type got_offset = this->got_plt_->current_data_size();
1126 // Every PLT entry needs a GOT entry which points back to the
1127 // PLT entry (this will be changed by the dynamic linker,
1128 // normally lazily when the function is called).
1129 this->got_plt_->set_current_data_size(got_offset + 4);
1131 gsym->set_needs_dynsym_entry();
1132 this->rel_->add_global(gsym, elfcpp::R_386_JUMP_SLOT, this->got_plt_,
1136 // Note that we don't need to save the symbol. The contents of the
1137 // PLT are independent of which symbols are used. The symbols only
1138 // appear in the relocations.
1141 // Add an entry to the PLT for a local STT_GNU_IFUNC symbol. Return
1145 Output_data_plt_i386::add_local_ifunc_entry(
1146 Symbol_table* symtab,
1148 Sized_relobj_file<32, false>* relobj,
1149 unsigned int local_sym_index)
1151 unsigned int plt_offset = this->irelative_count_ * this->get_plt_entry_size();
1152 ++this->irelative_count_;
1154 section_offset_type got_offset = this->got_irelative_->current_data_size();
1156 // Every PLT entry needs a GOT entry which points back to the PLT
1158 this->got_irelative_->set_current_data_size(got_offset + 4);
1160 // Every PLT entry needs a reloc.
1161 Reloc_section* rel = this->rel_irelative(symtab, layout);
1162 rel->add_symbolless_local_addend(relobj, local_sym_index,
1163 elfcpp::R_386_IRELATIVE,
1164 this->got_irelative_, got_offset);
1166 struct Local_ifunc li;
1168 li.local_sym_index = local_sym_index;
1169 li.got_offset = got_offset;
1170 this->local_ifuncs_.push_back(li);
1175 // Return where the TLS_DESC relocations should go, creating it if
1176 // necessary. These follow the JUMP_SLOT relocations.
1178 Output_data_plt_i386::Reloc_section*
1179 Output_data_plt_i386::rel_tls_desc(Layout* layout)
1181 if (this->tls_desc_rel_ == NULL)
1183 this->tls_desc_rel_ = new Reloc_section(false);
1184 layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL,
1185 elfcpp::SHF_ALLOC, this->tls_desc_rel_,
1186 ORDER_DYNAMIC_PLT_RELOCS, false);
1187 gold_assert(this->tls_desc_rel_->output_section()
1188 == this->rel_->output_section());
1190 return this->tls_desc_rel_;
1193 // Return where the IRELATIVE relocations should go in the PLT. These
1194 // follow the JUMP_SLOT and TLS_DESC relocations.
1196 Output_data_plt_i386::Reloc_section*
1197 Output_data_plt_i386::rel_irelative(Symbol_table* symtab, Layout* layout)
1199 if (this->irelative_rel_ == NULL)
1201 // Make sure we have a place for the TLS_DESC relocations, in
1202 // case we see any later on.
1203 this->rel_tls_desc(layout);
1204 this->irelative_rel_ = new Reloc_section(false);
1205 layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL,
1206 elfcpp::SHF_ALLOC, this->irelative_rel_,
1207 ORDER_DYNAMIC_PLT_RELOCS, false);
1208 gold_assert(this->irelative_rel_->output_section()
1209 == this->rel_->output_section());
1211 if (parameters->doing_static_link())
1213 // A statically linked executable will only have a .rel.plt
1214 // section to hold R_386_IRELATIVE relocs for STT_GNU_IFUNC
1215 // symbols. The library will use these symbols to locate
1216 // the IRELATIVE relocs at program startup time.
1217 symtab->define_in_output_data("__rel_iplt_start", NULL,
1218 Symbol_table::PREDEFINED,
1219 this->irelative_rel_, 0, 0,
1220 elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL,
1221 elfcpp::STV_HIDDEN, 0, false, true);
1222 symtab->define_in_output_data("__rel_iplt_end", NULL,
1223 Symbol_table::PREDEFINED,
1224 this->irelative_rel_, 0, 0,
1225 elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL,
1226 elfcpp::STV_HIDDEN, 0, true, true);
1229 return this->irelative_rel_;
1232 // Return the PLT address to use for a global symbol.
1235 Output_data_plt_i386::address_for_global(const Symbol* gsym)
1237 uint64_t offset = 0;
1238 if (gsym->type() == elfcpp::STT_GNU_IFUNC
1239 && gsym->can_use_relative_reloc(false))
1240 offset = (this->count_ + 1) * this->get_plt_entry_size();
1241 return this->address() + offset + gsym->plt_offset();
1244 // Return the PLT address to use for a local symbol. These are always
1245 // IRELATIVE relocs.
1248 Output_data_plt_i386::address_for_local(const Relobj* object,
1251 return (this->address()
1252 + (this->count_ + 1) * this->get_plt_entry_size()
1253 + object->local_plt_offset(r_sym));
1256 // The first entry in the PLT for an executable.
1258 const unsigned char Output_data_plt_i386_exec::first_plt_entry[plt_entry_size] =
1260 0xff, 0x35, // pushl contents of memory address
1261 0, 0, 0, 0, // replaced with address of .got + 4
1262 0xff, 0x25, // jmp indirect
1263 0, 0, 0, 0, // replaced with address of .got + 8
1264 0, 0, 0, 0 // unused
1268 Output_data_plt_i386_exec::do_fill_first_plt_entry(
1270 elfcpp::Elf_types<32>::Elf_Addr got_address)
1272 memcpy(pov, first_plt_entry, plt_entry_size);
1273 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_address + 4);
1274 elfcpp::Swap<32, false>::writeval(pov + 8, got_address + 8);
1277 // The first entry in the PLT for a shared object.
1279 const unsigned char Output_data_plt_i386_dyn::first_plt_entry[plt_entry_size] =
1281 0xff, 0xb3, 4, 0, 0, 0, // pushl 4(%ebx)
1282 0xff, 0xa3, 8, 0, 0, 0, // jmp *8(%ebx)
1283 0, 0, 0, 0 // unused
1287 Output_data_plt_i386_dyn::do_fill_first_plt_entry(
1289 elfcpp::Elf_types<32>::Elf_Addr)
1291 memcpy(pov, first_plt_entry, plt_entry_size);
1294 // Subsequent entries in the PLT for an executable.
1296 const unsigned char Output_data_plt_i386_exec::plt_entry[plt_entry_size] =
1298 0xff, 0x25, // jmp indirect
1299 0, 0, 0, 0, // replaced with address of symbol in .got
1300 0x68, // pushl immediate
1301 0, 0, 0, 0, // replaced with offset into relocation table
1302 0xe9, // jmp relative
1303 0, 0, 0, 0 // replaced with offset to start of .plt
1307 Output_data_plt_i386_exec::do_fill_plt_entry(
1309 elfcpp::Elf_types<32>::Elf_Addr got_address,
1310 unsigned int got_offset,
1311 unsigned int plt_offset,
1312 unsigned int plt_rel_offset)
1314 memcpy(pov, plt_entry, plt_entry_size);
1315 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
1316 got_address + got_offset);
1317 elfcpp::Swap_unaligned<32, false>::writeval(pov + 7, plt_rel_offset);
1318 elfcpp::Swap<32, false>::writeval(pov + 12, - (plt_offset + 12 + 4));
1322 // Subsequent entries in the PLT for a shared object.
1324 const unsigned char Output_data_plt_i386_dyn::plt_entry[plt_entry_size] =
1326 0xff, 0xa3, // jmp *offset(%ebx)
1327 0, 0, 0, 0, // replaced with offset of symbol in .got
1328 0x68, // pushl immediate
1329 0, 0, 0, 0, // replaced with offset into relocation table
1330 0xe9, // jmp relative
1331 0, 0, 0, 0 // replaced with offset to start of .plt
1335 Output_data_plt_i386_dyn::do_fill_plt_entry(unsigned char* pov,
1336 elfcpp::Elf_types<32>::Elf_Addr,
1337 unsigned int got_offset,
1338 unsigned int plt_offset,
1339 unsigned int plt_rel_offset)
1341 memcpy(pov, plt_entry, plt_entry_size);
1342 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_offset);
1343 elfcpp::Swap_unaligned<32, false>::writeval(pov + 7, plt_rel_offset);
1344 elfcpp::Swap<32, false>::writeval(pov + 12, - (plt_offset + 12 + 4));
1348 // The .eh_frame unwind information for the PLT.
1351 Output_data_plt_i386::plt_eh_frame_cie[plt_eh_frame_cie_size] =
1354 'z', // Augmentation: augmentation size included.
1355 'R', // Augmentation: FDE encoding included.
1356 '\0', // End of augmentation string.
1357 1, // Code alignment factor.
1358 0x7c, // Data alignment factor.
1359 8, // Return address column.
1360 1, // Augmentation size.
1361 (elfcpp::DW_EH_PE_pcrel // FDE encoding.
1362 | elfcpp::DW_EH_PE_sdata4),
1363 elfcpp::DW_CFA_def_cfa, 4, 4, // DW_CFA_def_cfa: r4 (esp) ofs 4.
1364 elfcpp::DW_CFA_offset + 8, 1, // DW_CFA_offset: r8 (eip) at cfa-4.
1365 elfcpp::DW_CFA_nop, // Align to 16 bytes.
1370 Output_data_plt_i386_standard::plt_eh_frame_fde[plt_eh_frame_fde_size] =
1372 0, 0, 0, 0, // Replaced with offset to .plt.
1373 0, 0, 0, 0, // Replaced with size of .plt.
1374 0, // Augmentation size.
1375 elfcpp::DW_CFA_def_cfa_offset, 8, // DW_CFA_def_cfa_offset: 8.
1376 elfcpp::DW_CFA_advance_loc + 6, // Advance 6 to __PLT__ + 6.
1377 elfcpp::DW_CFA_def_cfa_offset, 12, // DW_CFA_def_cfa_offset: 12.
1378 elfcpp::DW_CFA_advance_loc + 10, // Advance 10 to __PLT__ + 16.
1379 elfcpp::DW_CFA_def_cfa_expression, // DW_CFA_def_cfa_expression.
1380 11, // Block length.
1381 elfcpp::DW_OP_breg4, 4, // Push %esp + 4.
1382 elfcpp::DW_OP_breg8, 0, // Push %eip.
1383 elfcpp::DW_OP_lit15, // Push 0xf.
1384 elfcpp::DW_OP_and, // & (%eip & 0xf).
1385 elfcpp::DW_OP_lit11, // Push 0xb.
1386 elfcpp::DW_OP_ge, // >= ((%eip & 0xf) >= 0xb)
1387 elfcpp::DW_OP_lit2, // Push 2.
1388 elfcpp::DW_OP_shl, // << (((%eip & 0xf) >= 0xb) << 2)
1389 elfcpp::DW_OP_plus, // + ((((%eip&0xf)>=0xb)<<2)+%esp+4
1390 elfcpp::DW_CFA_nop, // Align to 32 bytes.
1396 // Write out the PLT. This uses the hand-coded instructions above,
1397 // and adjusts them as needed. This is all specified by the i386 ELF
1398 // Processor Supplement.
1401 Output_data_plt_i386::do_write(Output_file* of)
1403 const off_t offset = this->offset();
1404 const section_size_type oview_size =
1405 convert_to_section_size_type(this->data_size());
1406 unsigned char* const oview = of->get_output_view(offset, oview_size);
1408 const off_t got_file_offset = this->got_plt_->offset();
1409 gold_assert(parameters->incremental_update()
1410 || (got_file_offset + this->got_plt_->data_size()
1411 == this->got_irelative_->offset()));
1412 const section_size_type got_size =
1413 convert_to_section_size_type(this->got_plt_->data_size()
1414 + this->got_irelative_->data_size());
1416 unsigned char* const got_view = of->get_output_view(got_file_offset,
1419 unsigned char* pov = oview;
1421 elfcpp::Elf_types<32>::Elf_Addr plt_address = this->address();
1422 elfcpp::Elf_types<32>::Elf_Addr got_address = this->got_plt_->address();
1424 this->fill_first_plt_entry(pov, got_address);
1425 pov += this->get_plt_entry_size();
1427 // The first three entries in the GOT are reserved, and are written
1428 // by Output_data_got_plt_i386::do_write.
1429 unsigned char* got_pov = got_view + 12;
1431 const int rel_size = elfcpp::Elf_sizes<32>::rel_size;
1433 unsigned int plt_offset = this->get_plt_entry_size();
1434 unsigned int plt_rel_offset = 0;
1435 unsigned int got_offset = 12;
1436 const unsigned int count = this->count_ + this->irelative_count_;
1437 for (unsigned int i = 0;
1440 pov += this->get_plt_entry_size(),
1442 plt_offset += this->get_plt_entry_size(),
1443 plt_rel_offset += rel_size,
1446 // Set and adjust the PLT entry itself.
1447 unsigned int lazy_offset = this->fill_plt_entry(pov,
1453 // Set the entry in the GOT.
1454 elfcpp::Swap<32, false>::writeval(got_pov,
1455 plt_address + plt_offset + lazy_offset);
1458 // If any STT_GNU_IFUNC symbols have PLT entries, we need to change
1459 // the GOT to point to the actual symbol value, rather than point to
1460 // the PLT entry. That will let the dynamic linker call the right
1461 // function when resolving IRELATIVE relocations.
1462 unsigned char* got_irelative_view = got_view + this->got_plt_->data_size();
1463 for (std::vector<Global_ifunc>::const_iterator p =
1464 this->global_ifuncs_.begin();
1465 p != this->global_ifuncs_.end();
1468 const Sized_symbol<32>* ssym =
1469 static_cast<const Sized_symbol<32>*>(p->sym);
1470 elfcpp::Swap<32, false>::writeval(got_irelative_view + p->got_offset,
1474 for (std::vector<Local_ifunc>::const_iterator p =
1475 this->local_ifuncs_.begin();
1476 p != this->local_ifuncs_.end();
1479 const Symbol_value<32>* psymval =
1480 p->object->local_symbol(p->local_sym_index);
1481 elfcpp::Swap<32, false>::writeval(got_irelative_view + p->got_offset,
1482 psymval->value(p->object, 0));
1485 gold_assert(static_cast<section_size_type>(pov - oview) == oview_size);
1486 gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size);
1488 of->write_output_view(offset, oview_size, oview);
1489 of->write_output_view(got_file_offset, got_size, got_view);
1492 // Create the PLT section.
1495 Target_i386::make_plt_section(Symbol_table* symtab, Layout* layout)
1497 if (this->plt_ == NULL)
1499 // Create the GOT sections first.
1500 this->got_section(symtab, layout);
1502 const bool dyn = parameters->options().output_is_position_independent();
1503 this->plt_ = this->make_data_plt(layout,
1505 this->got_irelative_,
1508 // Add unwind information if requested.
1509 if (parameters->options().ld_generated_unwind_info())
1510 this->plt_->add_eh_frame(layout);
1512 layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
1514 | elfcpp::SHF_EXECINSTR),
1515 this->plt_, ORDER_PLT, false);
1517 // Make the sh_info field of .rel.plt point to .plt.
1518 Output_section* rel_plt_os = this->plt_->rel_plt()->output_section();
1519 rel_plt_os->set_info_section(this->plt_->output_section());
1523 // Create a PLT entry for a global symbol.
1526 Target_i386::make_plt_entry(Symbol_table* symtab, Layout* layout, Symbol* gsym)
1528 if (gsym->has_plt_offset())
1530 if (this->plt_ == NULL)
1531 this->make_plt_section(symtab, layout);
1532 this->plt_->add_entry(symtab, layout, gsym);
1535 // Make a PLT entry for a local STT_GNU_IFUNC symbol.
1538 Target_i386::make_local_ifunc_plt_entry(Symbol_table* symtab, Layout* layout,
1539 Sized_relobj_file<32, false>* relobj,
1540 unsigned int local_sym_index)
1542 if (relobj->local_has_plt_offset(local_sym_index))
1544 if (this->plt_ == NULL)
1545 this->make_plt_section(symtab, layout);
1546 unsigned int plt_offset = this->plt_->add_local_ifunc_entry(symtab, layout,
1549 relobj->set_local_plt_offset(local_sym_index, plt_offset);
1552 // Return the number of entries in the PLT.
1555 Target_i386::plt_entry_count() const
1557 if (this->plt_ == NULL)
1559 return this->plt_->entry_count();
1562 // Return the offset of the first non-reserved PLT entry.
1565 Target_i386::first_plt_entry_offset() const
1567 return this->plt_->first_plt_entry_offset();
1570 // Return the size of each PLT entry.
1573 Target_i386::plt_entry_size() const
1575 return this->plt_->get_plt_entry_size();
1578 // Get the section to use for TLS_DESC relocations.
1580 Target_i386::Reloc_section*
1581 Target_i386::rel_tls_desc_section(Layout* layout) const
1583 return this->plt_section()->rel_tls_desc(layout);
1586 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
1589 Target_i386::define_tls_base_symbol(Symbol_table* symtab, Layout* layout)
1591 if (this->tls_base_symbol_defined_)
1594 Output_segment* tls_segment = layout->tls_segment();
1595 if (tls_segment != NULL)
1597 bool is_exec = parameters->options().output_is_executable();
1598 symtab->define_in_output_segment("_TLS_MODULE_BASE_", NULL,
1599 Symbol_table::PREDEFINED,
1603 elfcpp::STV_HIDDEN, 0,
1605 ? Symbol::SEGMENT_END
1606 : Symbol::SEGMENT_START),
1609 this->tls_base_symbol_defined_ = true;
1612 // Create a GOT entry for the TLS module index.
1615 Target_i386::got_mod_index_entry(Symbol_table* symtab, Layout* layout,
1616 Sized_relobj_file<32, false>* object)
1618 if (this->got_mod_index_offset_ == -1U)
1620 gold_assert(symtab != NULL && layout != NULL && object != NULL);
1621 Reloc_section* rel_dyn = this->rel_dyn_section(layout);
1622 Output_data_got<32, false>* got = this->got_section(symtab, layout);
1623 unsigned int got_offset = got->add_constant(0);
1624 rel_dyn->add_local(object, 0, elfcpp::R_386_TLS_DTPMOD32, got,
1626 got->add_constant(0);
1627 this->got_mod_index_offset_ = got_offset;
1629 return this->got_mod_index_offset_;
1632 // Optimize the TLS relocation type based on what we know about the
1633 // symbol. IS_FINAL is true if the final address of this symbol is
1634 // known at link time.
1636 tls::Tls_optimization
1637 Target_i386::optimize_tls_reloc(bool is_final, int r_type)
1639 // If we are generating a shared library, then we can't do anything
1641 if (parameters->options().shared())
1642 return tls::TLSOPT_NONE;
1646 case elfcpp::R_386_TLS_GD:
1647 case elfcpp::R_386_TLS_GOTDESC:
1648 case elfcpp::R_386_TLS_DESC_CALL:
1649 // These are General-Dynamic which permits fully general TLS
1650 // access. Since we know that we are generating an executable,
1651 // we can convert this to Initial-Exec. If we also know that
1652 // this is a local symbol, we can further switch to Local-Exec.
1654 return tls::TLSOPT_TO_LE;
1655 return tls::TLSOPT_TO_IE;
1657 case elfcpp::R_386_TLS_LDM:
1658 // This is Local-Dynamic, which refers to a local symbol in the
1659 // dynamic TLS block. Since we know that we generating an
1660 // executable, we can switch to Local-Exec.
1661 return tls::TLSOPT_TO_LE;
1663 case elfcpp::R_386_TLS_LDO_32:
1664 // Another type of Local-Dynamic relocation.
1665 return tls::TLSOPT_TO_LE;
1667 case elfcpp::R_386_TLS_IE:
1668 case elfcpp::R_386_TLS_GOTIE:
1669 case elfcpp::R_386_TLS_IE_32:
1670 // These are Initial-Exec relocs which get the thread offset
1671 // from the GOT. If we know that we are linking against the
1672 // local symbol, we can switch to Local-Exec, which links the
1673 // thread offset into the instruction.
1675 return tls::TLSOPT_TO_LE;
1676 return tls::TLSOPT_NONE;
1678 case elfcpp::R_386_TLS_LE:
1679 case elfcpp::R_386_TLS_LE_32:
1680 // When we already have Local-Exec, there is nothing further we
1682 return tls::TLSOPT_NONE;
1689 // Get the Reference_flags for a particular relocation.
1692 Target_i386::Scan::get_reference_flags(unsigned int r_type)
1696 case elfcpp::R_386_NONE:
1697 case elfcpp::R_386_GNU_VTINHERIT:
1698 case elfcpp::R_386_GNU_VTENTRY:
1699 case elfcpp::R_386_GOTPC:
1700 // No symbol reference.
1703 case elfcpp::R_386_32:
1704 case elfcpp::R_386_16:
1705 case elfcpp::R_386_8:
1706 return Symbol::ABSOLUTE_REF;
1708 case elfcpp::R_386_PC32:
1709 case elfcpp::R_386_PC16:
1710 case elfcpp::R_386_PC8:
1711 case elfcpp::R_386_GOTOFF:
1712 return Symbol::RELATIVE_REF;
1714 case elfcpp::R_386_PLT32:
1715 return Symbol::FUNCTION_CALL | Symbol::RELATIVE_REF;
1717 case elfcpp::R_386_GOT32:
1718 case elfcpp::R_386_GOT32X:
1720 return Symbol::ABSOLUTE_REF;
1722 case elfcpp::R_386_TLS_GD: // Global-dynamic
1723 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url)
1724 case elfcpp::R_386_TLS_DESC_CALL:
1725 case elfcpp::R_386_TLS_LDM: // Local-dynamic
1726 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
1727 case elfcpp::R_386_TLS_IE: // Initial-exec
1728 case elfcpp::R_386_TLS_IE_32:
1729 case elfcpp::R_386_TLS_GOTIE:
1730 case elfcpp::R_386_TLS_LE: // Local-exec
1731 case elfcpp::R_386_TLS_LE_32:
1732 return Symbol::TLS_REF;
1734 case elfcpp::R_386_COPY:
1735 case elfcpp::R_386_GLOB_DAT:
1736 case elfcpp::R_386_JUMP_SLOT:
1737 case elfcpp::R_386_RELATIVE:
1738 case elfcpp::R_386_IRELATIVE:
1739 case elfcpp::R_386_TLS_TPOFF:
1740 case elfcpp::R_386_TLS_DTPMOD32:
1741 case elfcpp::R_386_TLS_DTPOFF32:
1742 case elfcpp::R_386_TLS_TPOFF32:
1743 case elfcpp::R_386_TLS_DESC:
1744 case elfcpp::R_386_32PLT:
1745 case elfcpp::R_386_TLS_GD_32:
1746 case elfcpp::R_386_TLS_GD_PUSH:
1747 case elfcpp::R_386_TLS_GD_CALL:
1748 case elfcpp::R_386_TLS_GD_POP:
1749 case elfcpp::R_386_TLS_LDM_32:
1750 case elfcpp::R_386_TLS_LDM_PUSH:
1751 case elfcpp::R_386_TLS_LDM_CALL:
1752 case elfcpp::R_386_TLS_LDM_POP:
1753 case elfcpp::R_386_USED_BY_INTEL_200:
1755 // Not expected. We will give an error later.
1760 // Report an unsupported relocation against a local symbol.
1763 Target_i386::Scan::unsupported_reloc_local(Sized_relobj_file<32, false>* object,
1764 unsigned int r_type)
1766 gold_error(_("%s: unsupported reloc %u against local symbol"),
1767 object->name().c_str(), r_type);
1770 // Return whether we need to make a PLT entry for a relocation of a
1771 // given type against a STT_GNU_IFUNC symbol.
1774 Target_i386::Scan::reloc_needs_plt_for_ifunc(
1775 Sized_relobj_file<32, false>* object,
1776 unsigned int r_type)
1778 int flags = Scan::get_reference_flags(r_type);
1779 if (flags & Symbol::TLS_REF)
1780 gold_error(_("%s: unsupported TLS reloc %u for IFUNC symbol"),
1781 object->name().c_str(), r_type);
1785 // Scan a relocation for a local symbol.
1788 Target_i386::Scan::local(Symbol_table* symtab,
1790 Target_i386* target,
1791 Sized_relobj_file<32, false>* object,
1792 unsigned int data_shndx,
1793 Output_section* output_section,
1794 const elfcpp::Rel<32, false>& reloc,
1795 unsigned int r_type,
1796 const elfcpp::Sym<32, false>& lsym,
1802 // A local STT_GNU_IFUNC symbol may require a PLT entry.
1803 if (lsym.get_st_type() == elfcpp::STT_GNU_IFUNC
1804 && this->reloc_needs_plt_for_ifunc(object, r_type))
1806 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1807 target->make_local_ifunc_plt_entry(symtab, layout, object, r_sym);
1812 case elfcpp::R_386_NONE:
1813 case elfcpp::R_386_GNU_VTINHERIT:
1814 case elfcpp::R_386_GNU_VTENTRY:
1817 case elfcpp::R_386_32:
1818 // If building a shared library (or a position-independent
1819 // executable), we need to create a dynamic relocation for
1820 // this location. The relocation applied at link time will
1821 // apply the link-time value, so we flag the location with
1822 // an R_386_RELATIVE relocation so the dynamic loader can
1823 // relocate it easily.
1824 if (parameters->options().output_is_position_independent())
1826 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1827 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1828 rel_dyn->add_local_relative(object, r_sym, elfcpp::R_386_RELATIVE,
1829 output_section, data_shndx,
1830 reloc.get_r_offset());
1834 case elfcpp::R_386_16:
1835 case elfcpp::R_386_8:
1836 // If building a shared library (or a position-independent
1837 // executable), we need to create a dynamic relocation for
1838 // this location. Because the addend needs to remain in the
1839 // data section, we need to be careful not to apply this
1840 // relocation statically.
1841 if (parameters->options().output_is_position_independent())
1843 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1844 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1845 if (lsym.get_st_type() != elfcpp::STT_SECTION)
1846 rel_dyn->add_local(object, r_sym, r_type, output_section,
1847 data_shndx, reloc.get_r_offset());
1850 gold_assert(lsym.get_st_value() == 0);
1851 unsigned int shndx = lsym.get_st_shndx();
1853 shndx = object->adjust_sym_shndx(r_sym, shndx,
1856 object->error(_("section symbol %u has bad shndx %u"),
1859 rel_dyn->add_local_section(object, shndx,
1860 r_type, output_section,
1861 data_shndx, reloc.get_r_offset());
1866 case elfcpp::R_386_PC32:
1867 case elfcpp::R_386_PC16:
1868 case elfcpp::R_386_PC8:
1871 case elfcpp::R_386_PLT32:
1872 // Since we know this is a local symbol, we can handle this as a
1876 case elfcpp::R_386_GOTOFF:
1877 case elfcpp::R_386_GOTPC:
1878 // We need a GOT section.
1879 target->got_section(symtab, layout);
1882 case elfcpp::R_386_GOT32:
1883 case elfcpp::R_386_GOT32X:
1885 // We need GOT section.
1886 Output_data_got<32, false>* got = target->got_section(symtab, layout);
1888 // If the relocation symbol isn't IFUNC,
1889 // and is local, then we will convert
1890 // mov foo@GOT(%reg), %reg
1892 // lea foo@GOTOFF(%reg), %reg
1893 // in Relocate::relocate.
1894 if (reloc.get_r_offset() >= 2
1895 && lsym.get_st_type() != elfcpp::STT_GNU_IFUNC)
1897 section_size_type stype;
1898 const unsigned char* view = object->section_contents(data_shndx,
1900 if (view[reloc.get_r_offset() - 2] == 0x8b)
1904 // Otherwise, the symbol requires a GOT entry.
1905 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1907 // For a STT_GNU_IFUNC symbol we want the PLT offset. That
1908 // lets function pointers compare correctly with shared
1909 // libraries. Otherwise we would need an IRELATIVE reloc.
1911 if (lsym.get_st_type() == elfcpp::STT_GNU_IFUNC)
1912 is_new = got->add_local_plt(object, r_sym, GOT_TYPE_STANDARD);
1914 is_new = got->add_local(object, r_sym, GOT_TYPE_STANDARD);
1917 // If we are generating a shared object, we need to add a
1918 // dynamic RELATIVE relocation for this symbol's GOT entry.
1919 if (parameters->options().output_is_position_independent())
1921 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1922 unsigned int got_offset =
1923 object->local_got_offset(r_sym, GOT_TYPE_STANDARD);
1924 rel_dyn->add_local_relative(object, r_sym,
1925 elfcpp::R_386_RELATIVE,
1932 // These are relocations which should only be seen by the
1933 // dynamic linker, and should never be seen here.
1934 case elfcpp::R_386_COPY:
1935 case elfcpp::R_386_GLOB_DAT:
1936 case elfcpp::R_386_JUMP_SLOT:
1937 case elfcpp::R_386_RELATIVE:
1938 case elfcpp::R_386_IRELATIVE:
1939 case elfcpp::R_386_TLS_TPOFF:
1940 case elfcpp::R_386_TLS_DTPMOD32:
1941 case elfcpp::R_386_TLS_DTPOFF32:
1942 case elfcpp::R_386_TLS_TPOFF32:
1943 case elfcpp::R_386_TLS_DESC:
1944 gold_error(_("%s: unexpected reloc %u in object file"),
1945 object->name().c_str(), r_type);
1948 // These are initial TLS relocs, which are expected when
1950 case elfcpp::R_386_TLS_GD: // Global-dynamic
1951 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url)
1952 case elfcpp::R_386_TLS_DESC_CALL:
1953 case elfcpp::R_386_TLS_LDM: // Local-dynamic
1954 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
1955 case elfcpp::R_386_TLS_IE: // Initial-exec
1956 case elfcpp::R_386_TLS_IE_32:
1957 case elfcpp::R_386_TLS_GOTIE:
1958 case elfcpp::R_386_TLS_LE: // Local-exec
1959 case elfcpp::R_386_TLS_LE_32:
1961 bool output_is_shared = parameters->options().shared();
1962 const tls::Tls_optimization optimized_type
1963 = Target_i386::optimize_tls_reloc(!output_is_shared, r_type);
1966 case elfcpp::R_386_TLS_GD: // Global-dynamic
1967 if (optimized_type == tls::TLSOPT_NONE)
1969 // Create a pair of GOT entries for the module index and
1970 // dtv-relative offset.
1971 Output_data_got<32, false>* got
1972 = target->got_section(symtab, layout);
1973 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1974 unsigned int shndx = lsym.get_st_shndx();
1976 shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
1978 object->error(_("local symbol %u has bad shndx %u"),
1981 got->add_local_pair_with_rel(object, r_sym, shndx,
1983 target->rel_dyn_section(layout),
1984 elfcpp::R_386_TLS_DTPMOD32);
1986 else if (optimized_type != tls::TLSOPT_TO_LE)
1987 unsupported_reloc_local(object, r_type);
1990 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva)
1991 target->define_tls_base_symbol(symtab, layout);
1992 if (optimized_type == tls::TLSOPT_NONE)
1994 // Create a double GOT entry with an R_386_TLS_DESC
1995 // reloc. The R_386_TLS_DESC reloc is resolved
1996 // lazily, so the GOT entry needs to be in an area in
1997 // .got.plt, not .got. Call got_section to make sure
1998 // the section has been created.
1999 target->got_section(symtab, layout);
2000 Output_data_got<32, false>* got = target->got_tlsdesc_section();
2001 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
2002 if (!object->local_has_got_offset(r_sym, GOT_TYPE_TLS_DESC))
2004 unsigned int got_offset = got->add_constant(0);
2005 // The local symbol value is stored in the second
2007 got->add_local(object, r_sym, GOT_TYPE_TLS_DESC);
2008 // That set the GOT offset of the local symbol to
2009 // point to the second entry, but we want it to
2010 // point to the first.
2011 object->set_local_got_offset(r_sym, GOT_TYPE_TLS_DESC,
2013 Reloc_section* rt = target->rel_tls_desc_section(layout);
2014 rt->add_absolute(elfcpp::R_386_TLS_DESC, got, got_offset);
2017 else if (optimized_type != tls::TLSOPT_TO_LE)
2018 unsupported_reloc_local(object, r_type);
2021 case elfcpp::R_386_TLS_DESC_CALL:
2024 case elfcpp::R_386_TLS_LDM: // Local-dynamic
2025 if (optimized_type == tls::TLSOPT_NONE)
2027 // Create a GOT entry for the module index.
2028 target->got_mod_index_entry(symtab, layout, object);
2030 else if (optimized_type != tls::TLSOPT_TO_LE)
2031 unsupported_reloc_local(object, r_type);
2034 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
2037 case elfcpp::R_386_TLS_IE: // Initial-exec
2038 case elfcpp::R_386_TLS_IE_32:
2039 case elfcpp::R_386_TLS_GOTIE:
2040 layout->set_has_static_tls();
2041 if (optimized_type == tls::TLSOPT_NONE)
2043 // For the R_386_TLS_IE relocation, we need to create a
2044 // dynamic relocation when building a shared library.
2045 if (r_type == elfcpp::R_386_TLS_IE
2046 && parameters->options().shared())
2048 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
2050 = elfcpp::elf_r_sym<32>(reloc.get_r_info());
2051 rel_dyn->add_local_relative(object, r_sym,
2052 elfcpp::R_386_RELATIVE,
2053 output_section, data_shndx,
2054 reloc.get_r_offset());
2056 // Create a GOT entry for the tp-relative offset.
2057 Output_data_got<32, false>* got
2058 = target->got_section(symtab, layout);
2059 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
2060 unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_IE_32
2061 ? elfcpp::R_386_TLS_TPOFF32
2062 : elfcpp::R_386_TLS_TPOFF);
2063 unsigned int got_type = (r_type == elfcpp::R_386_TLS_IE_32
2064 ? GOT_TYPE_TLS_OFFSET
2065 : GOT_TYPE_TLS_NOFFSET);
2066 got->add_local_with_rel(object, r_sym, got_type,
2067 target->rel_dyn_section(layout),
2070 else if (optimized_type != tls::TLSOPT_TO_LE)
2071 unsupported_reloc_local(object, r_type);
2074 case elfcpp::R_386_TLS_LE: // Local-exec
2075 case elfcpp::R_386_TLS_LE_32:
2076 layout->set_has_static_tls();
2077 if (output_is_shared)
2079 // We need to create a dynamic relocation.
2080 gold_assert(lsym.get_st_type() != elfcpp::STT_SECTION);
2081 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
2082 unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_LE_32
2083 ? elfcpp::R_386_TLS_TPOFF32
2084 : elfcpp::R_386_TLS_TPOFF);
2085 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
2086 rel_dyn->add_local(object, r_sym, dyn_r_type, output_section,
2087 data_shndx, reloc.get_r_offset());
2097 case elfcpp::R_386_32PLT:
2098 case elfcpp::R_386_TLS_GD_32:
2099 case elfcpp::R_386_TLS_GD_PUSH:
2100 case elfcpp::R_386_TLS_GD_CALL:
2101 case elfcpp::R_386_TLS_GD_POP:
2102 case elfcpp::R_386_TLS_LDM_32:
2103 case elfcpp::R_386_TLS_LDM_PUSH:
2104 case elfcpp::R_386_TLS_LDM_CALL:
2105 case elfcpp::R_386_TLS_LDM_POP:
2106 case elfcpp::R_386_USED_BY_INTEL_200:
2108 unsupported_reloc_local(object, r_type);
2113 // Report an unsupported relocation against a global symbol.
2116 Target_i386::Scan::unsupported_reloc_global(
2117 Sized_relobj_file<32, false>* object,
2118 unsigned int r_type,
2121 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
2122 object->name().c_str(), r_type, gsym->demangled_name().c_str());
2126 Target_i386::Scan::possible_function_pointer_reloc(unsigned int r_type)
2130 case elfcpp::R_386_32:
2131 case elfcpp::R_386_16:
2132 case elfcpp::R_386_8:
2133 case elfcpp::R_386_GOTOFF:
2134 case elfcpp::R_386_GOT32:
2135 case elfcpp::R_386_GOT32X:
2146 Target_i386::Scan::local_reloc_may_be_function_pointer(
2150 Sized_relobj_file<32, false>* ,
2153 const elfcpp::Rel<32, false>& ,
2154 unsigned int r_type,
2155 const elfcpp::Sym<32, false>&)
2157 return possible_function_pointer_reloc(r_type);
2161 Target_i386::Scan::global_reloc_may_be_function_pointer(
2165 Sized_relobj_file<32, false>* ,
2168 const elfcpp::Rel<32, false>& ,
2169 unsigned int r_type,
2172 return possible_function_pointer_reloc(r_type);
2175 // Scan a relocation for a global symbol.
2178 Target_i386::Scan::global(Symbol_table* symtab,
2180 Target_i386* target,
2181 Sized_relobj_file<32, false>* object,
2182 unsigned int data_shndx,
2183 Output_section* output_section,
2184 const elfcpp::Rel<32, false>& reloc,
2185 unsigned int r_type,
2188 // A STT_GNU_IFUNC symbol may require a PLT entry.
2189 if (gsym->type() == elfcpp::STT_GNU_IFUNC
2190 && this->reloc_needs_plt_for_ifunc(object, r_type))
2191 target->make_plt_entry(symtab, layout, gsym);
2195 case elfcpp::R_386_NONE:
2196 case elfcpp::R_386_GNU_VTINHERIT:
2197 case elfcpp::R_386_GNU_VTENTRY:
2200 case elfcpp::R_386_32:
2201 case elfcpp::R_386_16:
2202 case elfcpp::R_386_8:
2204 // Make a PLT entry if necessary.
2205 if (gsym->needs_plt_entry())
2207 target->make_plt_entry(symtab, layout, gsym);
2208 // Since this is not a PC-relative relocation, we may be
2209 // taking the address of a function. In that case we need to
2210 // set the entry in the dynamic symbol table to the address of
2212 if (gsym->is_from_dynobj() && !parameters->options().shared())
2213 gsym->set_needs_dynsym_value();
2215 // Make a dynamic relocation if necessary.
2216 if (gsym->needs_dynamic_reloc(Scan::get_reference_flags(r_type)))
2218 if (!parameters->options().output_is_position_independent()
2219 && gsym->may_need_copy_reloc())
2221 target->copy_reloc(symtab, layout, object,
2222 data_shndx, output_section, gsym, reloc);
2224 else if (r_type == elfcpp::R_386_32
2225 && gsym->type() == elfcpp::STT_GNU_IFUNC
2226 && gsym->can_use_relative_reloc(false)
2227 && !gsym->is_from_dynobj()
2228 && !gsym->is_undefined()
2229 && !gsym->is_preemptible())
2231 // Use an IRELATIVE reloc for a locally defined
2232 // STT_GNU_IFUNC symbol. This makes a function
2233 // address in a PIE executable match the address in a
2234 // shared library that it links against.
2235 Reloc_section* rel_dyn = target->rel_irelative_section(layout);
2236 rel_dyn->add_symbolless_global_addend(gsym,
2237 elfcpp::R_386_IRELATIVE,
2240 reloc.get_r_offset());
2242 else if (r_type == elfcpp::R_386_32
2243 && gsym->can_use_relative_reloc(false))
2245 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
2246 rel_dyn->add_global_relative(gsym, elfcpp::R_386_RELATIVE,
2247 output_section, object,
2248 data_shndx, reloc.get_r_offset());
2252 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
2253 rel_dyn->add_global(gsym, r_type, output_section, object,
2254 data_shndx, reloc.get_r_offset());
2260 case elfcpp::R_386_PC32:
2261 case elfcpp::R_386_PC16:
2262 case elfcpp::R_386_PC8:
2264 // Make a PLT entry if necessary.
2265 if (gsym->needs_plt_entry())
2267 // These relocations are used for function calls only in
2268 // non-PIC code. For a 32-bit relocation in a shared library,
2269 // we'll need a text relocation anyway, so we can skip the
2270 // PLT entry and let the dynamic linker bind the call directly
2271 // to the target. For smaller relocations, we should use a
2272 // PLT entry to ensure that the call can reach.
2273 if (!parameters->options().shared()
2274 || r_type != elfcpp::R_386_PC32)
2275 target->make_plt_entry(symtab, layout, gsym);
2277 // Make a dynamic relocation if necessary.
2278 if (gsym->needs_dynamic_reloc(Scan::get_reference_flags(r_type)))
2280 if (parameters->options().output_is_executable()
2281 && gsym->may_need_copy_reloc())
2283 target->copy_reloc(symtab, layout, object,
2284 data_shndx, output_section, gsym, reloc);
2288 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
2289 rel_dyn->add_global(gsym, r_type, output_section, object,
2290 data_shndx, reloc.get_r_offset());
2296 case elfcpp::R_386_GOT32:
2297 case elfcpp::R_386_GOT32X:
2299 // The symbol requires a GOT section.
2300 Output_data_got<32, false>* got = target->got_section(symtab, layout);
2302 // If we convert this from
2303 // mov foo@GOT(%reg), %reg
2305 // lea foo@GOTOFF(%reg), %reg
2306 // in Relocate::relocate, then there is nothing to do here.
2307 if (reloc.get_r_offset() >= 2
2308 && Target_i386::can_convert_mov_to_lea(gsym))
2310 section_size_type stype;
2311 const unsigned char* view = object->section_contents(data_shndx,
2313 if (view[reloc.get_r_offset() - 2] == 0x8b)
2317 if (gsym->final_value_is_known())
2319 // For a STT_GNU_IFUNC symbol we want the PLT address.
2320 if (gsym->type() == elfcpp::STT_GNU_IFUNC)
2321 got->add_global_plt(gsym, GOT_TYPE_STANDARD);
2323 got->add_global(gsym, GOT_TYPE_STANDARD);
2327 // If this symbol is not fully resolved, we need to add a
2328 // GOT entry with a dynamic relocation.
2329 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
2331 // Use a GLOB_DAT rather than a RELATIVE reloc if:
2333 // 1) The symbol may be defined in some other module.
2335 // 2) We are building a shared library and this is a
2336 // protected symbol; using GLOB_DAT means that the dynamic
2337 // linker can use the address of the PLT in the main
2338 // executable when appropriate so that function address
2339 // comparisons work.
2341 // 3) This is a STT_GNU_IFUNC symbol in position dependent
2342 // code, again so that function address comparisons work.
2343 if (gsym->is_from_dynobj()
2344 || gsym->is_undefined()
2345 || gsym->is_preemptible()
2346 || (gsym->visibility() == elfcpp::STV_PROTECTED
2347 && parameters->options().shared())
2348 || (gsym->type() == elfcpp::STT_GNU_IFUNC
2349 && parameters->options().output_is_position_independent()))
2350 got->add_global_with_rel(gsym, GOT_TYPE_STANDARD,
2351 rel_dyn, elfcpp::R_386_GLOB_DAT);
2354 // For a STT_GNU_IFUNC symbol we want to write the PLT
2355 // offset into the GOT, so that function pointer
2356 // comparisons work correctly.
2358 if (gsym->type() != elfcpp::STT_GNU_IFUNC)
2359 is_new = got->add_global(gsym, GOT_TYPE_STANDARD);
2362 is_new = got->add_global_plt(gsym, GOT_TYPE_STANDARD);
2363 // Tell the dynamic linker to use the PLT address
2364 // when resolving relocations.
2365 if (gsym->is_from_dynobj()
2366 && !parameters->options().shared())
2367 gsym->set_needs_dynsym_value();
2371 unsigned int got_off = gsym->got_offset(GOT_TYPE_STANDARD);
2372 rel_dyn->add_global_relative(gsym, elfcpp::R_386_RELATIVE,
2380 case elfcpp::R_386_PLT32:
2381 // If the symbol is fully resolved, this is just a PC32 reloc.
2382 // Otherwise we need a PLT entry.
2383 if (gsym->final_value_is_known())
2385 // If building a shared library, we can also skip the PLT entry
2386 // if the symbol is defined in the output file and is protected
2388 if (gsym->is_defined()
2389 && !gsym->is_from_dynobj()
2390 && !gsym->is_preemptible())
2392 target->make_plt_entry(symtab, layout, gsym);
2395 case elfcpp::R_386_GOTOFF:
2396 case elfcpp::R_386_GOTPC:
2397 // We need a GOT section.
2398 target->got_section(symtab, layout);
2401 // These are relocations which should only be seen by the
2402 // dynamic linker, and should never be seen here.
2403 case elfcpp::R_386_COPY:
2404 case elfcpp::R_386_GLOB_DAT:
2405 case elfcpp::R_386_JUMP_SLOT:
2406 case elfcpp::R_386_RELATIVE:
2407 case elfcpp::R_386_IRELATIVE:
2408 case elfcpp::R_386_TLS_TPOFF:
2409 case elfcpp::R_386_TLS_DTPMOD32:
2410 case elfcpp::R_386_TLS_DTPOFF32:
2411 case elfcpp::R_386_TLS_TPOFF32:
2412 case elfcpp::R_386_TLS_DESC:
2413 gold_error(_("%s: unexpected reloc %u in object file"),
2414 object->name().c_str(), r_type);
2417 // These are initial tls relocs, which are expected when
2419 case elfcpp::R_386_TLS_GD: // Global-dynamic
2420 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url)
2421 case elfcpp::R_386_TLS_DESC_CALL:
2422 case elfcpp::R_386_TLS_LDM: // Local-dynamic
2423 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
2424 case elfcpp::R_386_TLS_IE: // Initial-exec
2425 case elfcpp::R_386_TLS_IE_32:
2426 case elfcpp::R_386_TLS_GOTIE:
2427 case elfcpp::R_386_TLS_LE: // Local-exec
2428 case elfcpp::R_386_TLS_LE_32:
2430 const bool is_final = gsym->final_value_is_known();
2431 const tls::Tls_optimization optimized_type
2432 = Target_i386::optimize_tls_reloc(is_final, r_type);
2435 case elfcpp::R_386_TLS_GD: // Global-dynamic
2436 if (optimized_type == tls::TLSOPT_NONE)
2438 // Create a pair of GOT entries for the module index and
2439 // dtv-relative offset.
2440 Output_data_got<32, false>* got
2441 = target->got_section(symtab, layout);
2442 got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_PAIR,
2443 target->rel_dyn_section(layout),
2444 elfcpp::R_386_TLS_DTPMOD32,
2445 elfcpp::R_386_TLS_DTPOFF32);
2447 else if (optimized_type == tls::TLSOPT_TO_IE)
2449 // Create a GOT entry for the tp-relative offset.
2450 Output_data_got<32, false>* got
2451 = target->got_section(symtab, layout);
2452 got->add_global_with_rel(gsym, GOT_TYPE_TLS_NOFFSET,
2453 target->rel_dyn_section(layout),
2454 elfcpp::R_386_TLS_TPOFF);
2456 else if (optimized_type != tls::TLSOPT_TO_LE)
2457 unsupported_reloc_global(object, r_type, gsym);
2460 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (~oliva url)
2461 target->define_tls_base_symbol(symtab, layout);
2462 if (optimized_type == tls::TLSOPT_NONE)
2464 // Create a double GOT entry with an R_386_TLS_DESC
2465 // reloc. The R_386_TLS_DESC reloc is resolved
2466 // lazily, so the GOT entry needs to be in an area in
2467 // .got.plt, not .got. Call got_section to make sure
2468 // the section has been created.
2469 target->got_section(symtab, layout);
2470 Output_data_got<32, false>* got = target->got_tlsdesc_section();
2471 Reloc_section* rt = target->rel_tls_desc_section(layout);
2472 got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_DESC, rt,
2473 elfcpp::R_386_TLS_DESC, 0);
2475 else if (optimized_type == tls::TLSOPT_TO_IE)
2477 // Create a GOT entry for the tp-relative offset.
2478 Output_data_got<32, false>* got
2479 = target->got_section(symtab, layout);
2480 got->add_global_with_rel(gsym, GOT_TYPE_TLS_NOFFSET,
2481 target->rel_dyn_section(layout),
2482 elfcpp::R_386_TLS_TPOFF);
2484 else if (optimized_type != tls::TLSOPT_TO_LE)
2485 unsupported_reloc_global(object, r_type, gsym);
2488 case elfcpp::R_386_TLS_DESC_CALL:
2491 case elfcpp::R_386_TLS_LDM: // Local-dynamic
2492 if (optimized_type == tls::TLSOPT_NONE)
2494 // Create a GOT entry for the module index.
2495 target->got_mod_index_entry(symtab, layout, object);
2497 else if (optimized_type != tls::TLSOPT_TO_LE)
2498 unsupported_reloc_global(object, r_type, gsym);
2501 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
2504 case elfcpp::R_386_TLS_IE: // Initial-exec
2505 case elfcpp::R_386_TLS_IE_32:
2506 case elfcpp::R_386_TLS_GOTIE:
2507 layout->set_has_static_tls();
2508 if (optimized_type == tls::TLSOPT_NONE)
2510 // For the R_386_TLS_IE relocation, we need to create a
2511 // dynamic relocation when building a shared library.
2512 if (r_type == elfcpp::R_386_TLS_IE
2513 && parameters->options().shared())
2515 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
2516 rel_dyn->add_global_relative(gsym, elfcpp::R_386_RELATIVE,
2517 output_section, object,
2519 reloc.get_r_offset());
2521 // Create a GOT entry for the tp-relative offset.
2522 Output_data_got<32, false>* got
2523 = target->got_section(symtab, layout);
2524 unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_IE_32
2525 ? elfcpp::R_386_TLS_TPOFF32
2526 : elfcpp::R_386_TLS_TPOFF);
2527 unsigned int got_type = (r_type == elfcpp::R_386_TLS_IE_32
2528 ? GOT_TYPE_TLS_OFFSET
2529 : GOT_TYPE_TLS_NOFFSET);
2530 got->add_global_with_rel(gsym, got_type,
2531 target->rel_dyn_section(layout),
2534 else if (optimized_type != tls::TLSOPT_TO_LE)
2535 unsupported_reloc_global(object, r_type, gsym);
2538 case elfcpp::R_386_TLS_LE: // Local-exec
2539 case elfcpp::R_386_TLS_LE_32:
2540 layout->set_has_static_tls();
2541 if (parameters->options().shared())
2543 // We need to create a dynamic relocation.
2544 unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_LE_32
2545 ? elfcpp::R_386_TLS_TPOFF32
2546 : elfcpp::R_386_TLS_TPOFF);
2547 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
2548 rel_dyn->add_global(gsym, dyn_r_type, output_section, object,
2549 data_shndx, reloc.get_r_offset());
2559 case elfcpp::R_386_32PLT:
2560 case elfcpp::R_386_TLS_GD_32:
2561 case elfcpp::R_386_TLS_GD_PUSH:
2562 case elfcpp::R_386_TLS_GD_CALL:
2563 case elfcpp::R_386_TLS_GD_POP:
2564 case elfcpp::R_386_TLS_LDM_32:
2565 case elfcpp::R_386_TLS_LDM_PUSH:
2566 case elfcpp::R_386_TLS_LDM_CALL:
2567 case elfcpp::R_386_TLS_LDM_POP:
2568 case elfcpp::R_386_USED_BY_INTEL_200:
2570 unsupported_reloc_global(object, r_type, gsym);
2575 // Process relocations for gc.
2578 Target_i386::gc_process_relocs(Symbol_table* symtab,
2580 Sized_relobj_file<32, false>* object,
2581 unsigned int data_shndx,
2583 const unsigned char* prelocs,
2585 Output_section* output_section,
2586 bool needs_special_offset_handling,
2587 size_t local_symbol_count,
2588 const unsigned char* plocal_symbols)
2590 gold::gc_process_relocs<32, false, Target_i386, Scan, Classify_reloc>(
2599 needs_special_offset_handling,
2604 // Scan relocations for a section.
2607 Target_i386::scan_relocs(Symbol_table* symtab,
2609 Sized_relobj_file<32, false>* object,
2610 unsigned int data_shndx,
2611 unsigned int sh_type,
2612 const unsigned char* prelocs,
2614 Output_section* output_section,
2615 bool needs_special_offset_handling,
2616 size_t local_symbol_count,
2617 const unsigned char* plocal_symbols)
2619 if (sh_type == elfcpp::SHT_RELA)
2621 gold_error(_("%s: unsupported RELA reloc section"),
2622 object->name().c_str());
2626 gold::scan_relocs<32, false, Target_i386, Scan, Classify_reloc>(
2635 needs_special_offset_handling,
2640 // Finalize the sections.
2643 Target_i386::do_finalize_sections(
2645 const Input_objects*,
2646 Symbol_table* symtab)
2648 const Reloc_section* rel_plt = (this->plt_ == NULL
2650 : this->plt_->rel_plt());
2651 layout->add_target_dynamic_tags(true, this->got_plt_, rel_plt,
2652 this->rel_dyn_, true, false);
2654 // Emit any relocs we saved in an attempt to avoid generating COPY
2656 if (this->copy_relocs_.any_saved_relocs())
2657 this->copy_relocs_.emit(this->rel_dyn_section(layout));
2659 // Set the size of the _GLOBAL_OFFSET_TABLE_ symbol to the size of
2660 // the .got.plt section.
2661 Symbol* sym = this->global_offset_table_;
2664 uint32_t data_size = this->got_plt_->current_data_size();
2665 symtab->get_sized_symbol<32>(sym)->set_symsize(data_size);
2668 if (parameters->doing_static_link()
2669 && (this->plt_ == NULL || !this->plt_->has_irelative_section()))
2671 // If linking statically, make sure that the __rel_iplt symbols
2672 // were defined if necessary, even if we didn't create a PLT.
2673 static const Define_symbol_in_segment syms[] =
2676 "__rel_iplt_start", // name
2677 elfcpp::PT_LOAD, // segment_type
2678 elfcpp::PF_W, // segment_flags_set
2679 elfcpp::PF(0), // segment_flags_clear
2682 elfcpp::STT_NOTYPE, // type
2683 elfcpp::STB_GLOBAL, // binding
2684 elfcpp::STV_HIDDEN, // visibility
2686 Symbol::SEGMENT_START, // offset_from_base
2690 "__rel_iplt_end", // name
2691 elfcpp::PT_LOAD, // segment_type
2692 elfcpp::PF_W, // segment_flags_set
2693 elfcpp::PF(0), // segment_flags_clear
2696 elfcpp::STT_NOTYPE, // type
2697 elfcpp::STB_GLOBAL, // binding
2698 elfcpp::STV_HIDDEN, // visibility
2700 Symbol::SEGMENT_START, // offset_from_base
2705 symtab->define_symbols(layout, 2, syms,
2706 layout->script_options()->saw_sections_clause());
2710 // Return whether a direct absolute static relocation needs to be applied.
2711 // In cases where Scan::local() or Scan::global() has created
2712 // a dynamic relocation other than R_386_RELATIVE, the addend
2713 // of the relocation is carried in the data, and we must not
2714 // apply the static relocation.
2717 Target_i386::Relocate::should_apply_static_reloc(const Sized_symbol<32>* gsym,
2718 unsigned int r_type,
2720 Output_section* output_section)
2722 // If the output section is not allocated, then we didn't call
2723 // scan_relocs, we didn't create a dynamic reloc, and we must apply
2725 if ((output_section->flags() & elfcpp::SHF_ALLOC) == 0)
2728 int ref_flags = Scan::get_reference_flags(r_type);
2730 // For local symbols, we will have created a non-RELATIVE dynamic
2731 // relocation only if (a) the output is position independent,
2732 // (b) the relocation is absolute (not pc- or segment-relative), and
2733 // (c) the relocation is not 32 bits wide.
2735 return !(parameters->options().output_is_position_independent()
2736 && (ref_flags & Symbol::ABSOLUTE_REF)
2739 // For global symbols, we use the same helper routines used in the
2740 // scan pass. If we did not create a dynamic relocation, or if we
2741 // created a RELATIVE dynamic relocation, we should apply the static
2743 bool has_dyn = gsym->needs_dynamic_reloc(ref_flags);
2744 bool is_rel = (ref_flags & Symbol::ABSOLUTE_REF)
2745 && gsym->can_use_relative_reloc(ref_flags
2746 & Symbol::FUNCTION_CALL);
2747 return !has_dyn || is_rel;
2750 // Perform a relocation.
2753 Target_i386::Relocate::relocate(const Relocate_info<32, false>* relinfo,
2755 Target_i386* target,
2756 Output_section* output_section,
2758 const unsigned char* preloc,
2759 const Sized_symbol<32>* gsym,
2760 const Symbol_value<32>* psymval,
2761 unsigned char* view,
2762 elfcpp::Elf_types<32>::Elf_Addr address,
2763 section_size_type view_size)
2765 const elfcpp::Rel<32, false> rel(preloc);
2766 unsigned int r_type = elfcpp::elf_r_type<32>(rel.get_r_info());
2768 if (this->skip_call_tls_get_addr_)
2770 if ((r_type != elfcpp::R_386_PLT32
2771 && r_type != elfcpp::R_386_PC32)
2773 || strcmp(gsym->name(), "___tls_get_addr") != 0)
2774 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
2775 _("missing expected TLS relocation"));
2778 this->skip_call_tls_get_addr_ = false;
2786 const Sized_relobj_file<32, false>* object = relinfo->object;
2788 // Pick the value to use for symbols defined in shared objects.
2789 Symbol_value<32> symval;
2791 && gsym->type() == elfcpp::STT_GNU_IFUNC
2792 && r_type == elfcpp::R_386_32
2793 && gsym->needs_dynamic_reloc(Scan::get_reference_flags(r_type))
2794 && gsym->can_use_relative_reloc(false)
2795 && !gsym->is_from_dynobj()
2796 && !gsym->is_undefined()
2797 && !gsym->is_preemptible())
2799 // In this case we are generating a R_386_IRELATIVE reloc. We
2800 // want to use the real value of the symbol, not the PLT offset.
2802 else if (gsym != NULL
2803 && gsym->use_plt_offset(Scan::get_reference_flags(r_type)))
2805 symval.set_output_value(target->plt_address_for_global(gsym));
2808 else if (gsym == NULL && psymval->is_ifunc_symbol())
2810 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
2811 if (object->local_has_plt_offset(r_sym))
2813 symval.set_output_value(target->plt_address_for_local(object, r_sym));
2822 case elfcpp::R_386_NONE:
2823 case elfcpp::R_386_GNU_VTINHERIT:
2824 case elfcpp::R_386_GNU_VTENTRY:
2827 case elfcpp::R_386_32:
2828 if (should_apply_static_reloc(gsym, r_type, true, output_section))
2829 Relocate_functions<32, false>::rel32(view, object, psymval);
2832 case elfcpp::R_386_PC32:
2833 if (should_apply_static_reloc(gsym, r_type, true, output_section))
2834 Relocate_functions<32, false>::pcrel32(view, object, psymval, address);
2837 case elfcpp::R_386_16:
2838 if (should_apply_static_reloc(gsym, r_type, false, output_section))
2839 Relocate_functions<32, false>::rel16(view, object, psymval);
2842 case elfcpp::R_386_PC16:
2843 if (should_apply_static_reloc(gsym, r_type, false, output_section))
2844 Relocate_functions<32, false>::pcrel16(view, object, psymval, address);
2847 case elfcpp::R_386_8:
2848 if (should_apply_static_reloc(gsym, r_type, false, output_section))
2849 Relocate_functions<32, false>::rel8(view, object, psymval);
2852 case elfcpp::R_386_PC8:
2853 if (should_apply_static_reloc(gsym, r_type, false, output_section))
2854 Relocate_functions<32, false>::pcrel8(view, object, psymval, address);
2857 case elfcpp::R_386_PLT32:
2858 gold_assert(gsym == NULL
2859 || gsym->has_plt_offset()
2860 || gsym->final_value_is_known()
2861 || (gsym->is_defined()
2862 && !gsym->is_from_dynobj()
2863 && !gsym->is_preemptible()));
2864 Relocate_functions<32, false>::pcrel32(view, object, psymval, address);
2867 case elfcpp::R_386_GOT32:
2868 case elfcpp::R_386_GOT32X:
2869 baseless = (view[-1] & 0xc7) == 0x5;
2870 // R_386_GOT32 and R_386_GOT32X don't work without base register
2871 // when generating a position-independent output file.
2873 && parameters->options().output_is_position_independent())
2876 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
2877 _("unexpected reloc %u against global symbol %s without base register in object file when generating a position-independent output file"),
2878 r_type, gsym->demangled_name().c_str());
2880 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
2881 _("unexpected reloc %u against local symbol without base register in object file when generating a position-independent output file"),
2886 // mov foo@GOT(%reg), %reg
2888 // lea foo@GOTOFF(%reg), %reg
2890 if (rel.get_r_offset() >= 2
2892 && ((gsym == NULL && !psymval->is_ifunc_symbol())
2894 && Target_i386::can_convert_mov_to_lea(gsym))))
2897 elfcpp::Elf_types<32>::Elf_Addr value;
2898 value = psymval->value(object, 0);
2899 // Don't subtract the .got.plt section address for baseless
2902 value -= target->got_plt_section()->address();
2903 Relocate_functions<32, false>::rel32(view, value);
2907 // The GOT pointer points to the end of the GOT section.
2908 // We need to subtract the size of the GOT section to get
2909 // the actual offset to use in the relocation.
2910 unsigned int got_offset = 0;
2913 gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
2914 got_offset = (gsym->got_offset(GOT_TYPE_STANDARD)
2915 - target->got_size());
2919 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
2920 gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD));
2921 got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD)
2922 - target->got_size());
2924 // Add the .got.plt section address for baseless addressing.
2926 got_offset += target->got_plt_section()->address();
2927 Relocate_functions<32, false>::rel32(view, got_offset);
2931 case elfcpp::R_386_GOTOFF:
2933 elfcpp::Elf_types<32>::Elf_Addr value;
2934 value = (psymval->value(object, 0)
2935 - target->got_plt_section()->address());
2936 Relocate_functions<32, false>::rel32(view, value);
2940 case elfcpp::R_386_GOTPC:
2942 elfcpp::Elf_types<32>::Elf_Addr value;
2943 value = target->got_plt_section()->address();
2944 Relocate_functions<32, false>::pcrel32(view, value, address);
2948 case elfcpp::R_386_COPY:
2949 case elfcpp::R_386_GLOB_DAT:
2950 case elfcpp::R_386_JUMP_SLOT:
2951 case elfcpp::R_386_RELATIVE:
2952 case elfcpp::R_386_IRELATIVE:
2953 // These are outstanding tls relocs, which are unexpected when
2955 case elfcpp::R_386_TLS_TPOFF:
2956 case elfcpp::R_386_TLS_DTPMOD32:
2957 case elfcpp::R_386_TLS_DTPOFF32:
2958 case elfcpp::R_386_TLS_TPOFF32:
2959 case elfcpp::R_386_TLS_DESC:
2960 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
2961 _("unexpected reloc %u in object file"),
2965 // These are initial tls relocs, which are expected when
2967 case elfcpp::R_386_TLS_GD: // Global-dynamic
2968 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url)
2969 case elfcpp::R_386_TLS_DESC_CALL:
2970 case elfcpp::R_386_TLS_LDM: // Local-dynamic
2971 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
2972 case elfcpp::R_386_TLS_IE: // Initial-exec
2973 case elfcpp::R_386_TLS_IE_32:
2974 case elfcpp::R_386_TLS_GOTIE:
2975 case elfcpp::R_386_TLS_LE: // Local-exec
2976 case elfcpp::R_386_TLS_LE_32:
2977 this->relocate_tls(relinfo, target, relnum, rel, r_type, gsym, psymval,
2978 view, address, view_size);
2981 case elfcpp::R_386_32PLT:
2982 case elfcpp::R_386_TLS_GD_32:
2983 case elfcpp::R_386_TLS_GD_PUSH:
2984 case elfcpp::R_386_TLS_GD_CALL:
2985 case elfcpp::R_386_TLS_GD_POP:
2986 case elfcpp::R_386_TLS_LDM_32:
2987 case elfcpp::R_386_TLS_LDM_PUSH:
2988 case elfcpp::R_386_TLS_LDM_CALL:
2989 case elfcpp::R_386_TLS_LDM_POP:
2990 case elfcpp::R_386_USED_BY_INTEL_200:
2992 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
2993 _("unsupported reloc %u"),
3001 // Perform a TLS relocation.
3004 Target_i386::Relocate::relocate_tls(const Relocate_info<32, false>* relinfo,
3005 Target_i386* target,
3007 const elfcpp::Rel<32, false>& rel,
3008 unsigned int r_type,
3009 const Sized_symbol<32>* gsym,
3010 const Symbol_value<32>* psymval,
3011 unsigned char* view,
3012 elfcpp::Elf_types<32>::Elf_Addr,
3013 section_size_type view_size)
3015 Output_segment* tls_segment = relinfo->layout->tls_segment();
3017 const Sized_relobj_file<32, false>* object = relinfo->object;
3019 elfcpp::Elf_types<32>::Elf_Addr value = psymval->value(object, 0);
3021 const bool is_final = (gsym == NULL
3022 ? !parameters->options().shared()
3023 : gsym->final_value_is_known());
3024 const tls::Tls_optimization optimized_type
3025 = Target_i386::optimize_tls_reloc(is_final, r_type);
3028 case elfcpp::R_386_TLS_GD: // Global-dynamic
3029 if (optimized_type == tls::TLSOPT_TO_LE)
3031 if (tls_segment == NULL)
3033 gold_assert(parameters->errors()->error_count() > 0
3034 || issue_undefined_symbol_error(gsym));
3037 this->tls_gd_to_le(relinfo, relnum, tls_segment,
3038 rel, r_type, value, view,
3044 unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE
3045 ? GOT_TYPE_TLS_NOFFSET
3046 : GOT_TYPE_TLS_PAIR);
3047 unsigned int got_offset;
3050 gold_assert(gsym->has_got_offset(got_type));
3051 got_offset = gsym->got_offset(got_type) - target->got_size();
3055 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
3056 gold_assert(object->local_has_got_offset(r_sym, got_type));
3057 got_offset = (object->local_got_offset(r_sym, got_type)
3058 - target->got_size());
3060 if (optimized_type == tls::TLSOPT_TO_IE)
3062 this->tls_gd_to_ie(relinfo, relnum, rel, r_type,
3063 got_offset, view, view_size);
3066 else if (optimized_type == tls::TLSOPT_NONE)
3068 // Relocate the field with the offset of the pair of GOT
3070 Relocate_functions<32, false>::rel32(view, got_offset);
3074 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
3075 _("unsupported reloc %u"),
3079 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url)
3080 case elfcpp::R_386_TLS_DESC_CALL:
3081 this->local_dynamic_type_ = LOCAL_DYNAMIC_GNU;
3082 if (optimized_type == tls::TLSOPT_TO_LE)
3084 if (tls_segment == NULL)
3086 gold_assert(parameters->errors()->error_count() > 0
3087 || issue_undefined_symbol_error(gsym));
3090 this->tls_desc_gd_to_le(relinfo, relnum, tls_segment,
3091 rel, r_type, value, view,
3097 unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE
3098 ? GOT_TYPE_TLS_NOFFSET
3099 : GOT_TYPE_TLS_DESC);
3100 unsigned int got_offset = 0;
3101 if (r_type == elfcpp::R_386_TLS_GOTDESC
3102 && optimized_type == tls::TLSOPT_NONE)
3104 // We created GOT entries in the .got.tlsdesc portion of
3105 // the .got.plt section, but the offset stored in the
3106 // symbol is the offset within .got.tlsdesc.
3107 got_offset = (target->got_size()
3108 + target->got_plt_section()->data_size());
3112 gold_assert(gsym->has_got_offset(got_type));
3113 got_offset += gsym->got_offset(got_type) - target->got_size();
3117 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
3118 gold_assert(object->local_has_got_offset(r_sym, got_type));
3119 got_offset += (object->local_got_offset(r_sym, got_type)
3120 - target->got_size());
3122 if (optimized_type == tls::TLSOPT_TO_IE)
3124 this->tls_desc_gd_to_ie(relinfo, relnum, rel, r_type,
3125 got_offset, view, view_size);
3128 else if (optimized_type == tls::TLSOPT_NONE)
3130 if (r_type == elfcpp::R_386_TLS_GOTDESC)
3132 // Relocate the field with the offset of the pair of GOT
3134 Relocate_functions<32, false>::rel32(view, got_offset);
3139 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
3140 _("unsupported reloc %u"),
3144 case elfcpp::R_386_TLS_LDM: // Local-dynamic
3145 if (this->local_dynamic_type_ == LOCAL_DYNAMIC_SUN)
3147 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
3148 _("both SUN and GNU model "
3149 "TLS relocations"));
3152 this->local_dynamic_type_ = LOCAL_DYNAMIC_GNU;
3153 if (optimized_type == tls::TLSOPT_TO_LE)
3155 if (tls_segment == NULL)
3157 gold_assert(parameters->errors()->error_count() > 0
3158 || issue_undefined_symbol_error(gsym));
3161 this->tls_ld_to_le(relinfo, relnum, tls_segment, rel, r_type,
3162 value, view, view_size);
3165 else if (optimized_type == tls::TLSOPT_NONE)
3167 // Relocate the field with the offset of the GOT entry for
3168 // the module index.
3169 unsigned int got_offset;
3170 got_offset = (target->got_mod_index_entry(NULL, NULL, NULL)
3171 - target->got_size());
3172 Relocate_functions<32, false>::rel32(view, got_offset);
3175 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
3176 _("unsupported reloc %u"),
3180 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
3181 if (optimized_type == tls::TLSOPT_TO_LE)
3183 // This reloc can appear in debugging sections, in which
3184 // case we must not convert to local-exec. We decide what
3185 // to do based on whether the section is marked as
3186 // containing executable code. That is what the GNU linker
3188 elfcpp::Shdr<32, false> shdr(relinfo->data_shdr);
3189 if ((shdr.get_sh_flags() & elfcpp::SHF_EXECINSTR) != 0)
3191 if (tls_segment == NULL)
3193 gold_assert(parameters->errors()->error_count() > 0
3194 || issue_undefined_symbol_error(gsym));
3197 value -= tls_segment->memsz();
3200 Relocate_functions<32, false>::rel32(view, value);
3203 case elfcpp::R_386_TLS_IE: // Initial-exec
3204 case elfcpp::R_386_TLS_GOTIE:
3205 case elfcpp::R_386_TLS_IE_32:
3206 if (optimized_type == tls::TLSOPT_TO_LE)
3208 if (tls_segment == NULL)
3210 gold_assert(parameters->errors()->error_count() > 0
3211 || issue_undefined_symbol_error(gsym));
3214 Target_i386::Relocate::tls_ie_to_le(relinfo, relnum, tls_segment,
3215 rel, r_type, value, view,
3219 else if (optimized_type == tls::TLSOPT_NONE)
3221 // Relocate the field with the offset of the GOT entry for
3222 // the tp-relative offset of the symbol.
3223 unsigned int got_type = (r_type == elfcpp::R_386_TLS_IE_32
3224 ? GOT_TYPE_TLS_OFFSET
3225 : GOT_TYPE_TLS_NOFFSET);
3226 unsigned int got_offset;
3229 gold_assert(gsym->has_got_offset(got_type));
3230 got_offset = gsym->got_offset(got_type);
3234 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
3235 gold_assert(object->local_has_got_offset(r_sym, got_type));
3236 got_offset = object->local_got_offset(r_sym, got_type);
3238 // For the R_386_TLS_IE relocation, we need to apply the
3239 // absolute address of the GOT entry.
3240 if (r_type == elfcpp::R_386_TLS_IE)
3241 got_offset += target->got_plt_section()->address();
3242 // All GOT offsets are relative to the end of the GOT.
3243 got_offset -= target->got_size();
3244 Relocate_functions<32, false>::rel32(view, got_offset);
3247 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
3248 _("unsupported reloc %u"),
3252 case elfcpp::R_386_TLS_LE: // Local-exec
3253 // If we're creating a shared library, a dynamic relocation will
3254 // have been created for this location, so do not apply it now.
3255 if (!parameters->options().shared())
3257 if (tls_segment == NULL)
3259 gold_assert(parameters->errors()->error_count() > 0
3260 || issue_undefined_symbol_error(gsym));
3263 value -= tls_segment->memsz();
3264 Relocate_functions<32, false>::rel32(view, value);
3268 case elfcpp::R_386_TLS_LE_32:
3269 // If we're creating a shared library, a dynamic relocation will
3270 // have been created for this location, so do not apply it now.
3271 if (!parameters->options().shared())
3273 if (tls_segment == NULL)
3275 gold_assert(parameters->errors()->error_count() > 0
3276 || issue_undefined_symbol_error(gsym));
3279 value = tls_segment->memsz() - value;
3280 Relocate_functions<32, false>::rel32(view, value);
3286 // Do a relocation in which we convert a TLS General-Dynamic to a
3290 Target_i386::Relocate::tls_gd_to_le(const Relocate_info<32, false>* relinfo,
3292 Output_segment* tls_segment,
3293 const elfcpp::Rel<32, false>& rel,
3295 elfcpp::Elf_types<32>::Elf_Addr value,
3296 unsigned char* view,
3297 section_size_type view_size)
3299 // leal foo(,%reg,1),%eax; call ___tls_get_addr
3300 // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
3301 // leal foo(%reg),%eax; call ___tls_get_addr
3302 // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
3304 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
3305 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 9);
3307 unsigned char op1 = view[-1];
3308 unsigned char op2 = view[-2];
3310 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3311 op2 == 0x8d || op2 == 0x04);
3312 tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[4] == 0xe8);
3318 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -3);
3319 tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[-3] == 0x8d);
3320 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3321 ((op1 & 0xc7) == 0x05 && op1 != (4 << 3)));
3322 memcpy(view - 3, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
3326 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3327 (op1 & 0xf8) == 0x80 && (op1 & 7) != 4);
3328 if (rel.get_r_offset() + 9 < view_size
3331 // There is a trailing nop. Use the size byte subl.
3332 memcpy(view - 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
3337 // Use the five byte subl.
3338 memcpy(view - 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
3342 value = tls_segment->memsz() - value;
3343 Relocate_functions<32, false>::rel32(view + roff, value);
3345 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3347 this->skip_call_tls_get_addr_ = true;
3350 // Do a relocation in which we convert a TLS General-Dynamic to an
3354 Target_i386::Relocate::tls_gd_to_ie(const Relocate_info<32, false>* relinfo,
3356 const elfcpp::Rel<32, false>& rel,
3358 elfcpp::Elf_types<32>::Elf_Addr value,
3359 unsigned char* view,
3360 section_size_type view_size)
3362 // leal foo(,%ebx,1),%eax; call ___tls_get_addr
3363 // ==> movl %gs:0,%eax; addl foo@gotntpoff(%ebx),%eax
3364 // leal foo(%ebx),%eax; call ___tls_get_addr; nop
3365 // ==> movl %gs:0,%eax; addl foo@gotntpoff(%ebx),%eax
3367 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
3368 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 9);
3370 unsigned char op1 = view[-1];
3371 unsigned char op2 = view[-2];
3373 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3374 op2 == 0x8d || op2 == 0x04);
3375 tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[4] == 0xe8);
3381 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -3);
3382 tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[-3] == 0x8d);
3383 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3384 ((op1 & 0xc7) == 0x05 && op1 != (4 << 3)));
3389 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 10);
3390 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3391 (op1 & 0xf8) == 0x80 && (op1 & 7) != 4);
3392 tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[9] == 0x90);
3396 memcpy(view + roff - 8, "\x65\xa1\0\0\0\0\x03\x83\0\0\0", 12);
3397 Relocate_functions<32, false>::rel32(view + roff, value);
3399 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3401 this->skip_call_tls_get_addr_ = true;
3404 // Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL
3405 // General-Dynamic to a Local-Exec.
3408 Target_i386::Relocate::tls_desc_gd_to_le(
3409 const Relocate_info<32, false>* relinfo,
3411 Output_segment* tls_segment,
3412 const elfcpp::Rel<32, false>& rel,
3413 unsigned int r_type,
3414 elfcpp::Elf_types<32>::Elf_Addr value,
3415 unsigned char* view,
3416 section_size_type view_size)
3418 if (r_type == elfcpp::R_386_TLS_GOTDESC)
3420 // leal foo@TLSDESC(%ebx), %eax
3421 // ==> leal foo@NTPOFF, %eax
3422 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
3423 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4);
3424 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3425 view[-2] == 0x8d && view[-1] == 0x83);
3427 value -= tls_segment->memsz();
3428 Relocate_functions<32, false>::rel32(view, value);
3432 // call *foo@TLSCALL(%eax)
3434 gold_assert(r_type == elfcpp::R_386_TLS_DESC_CALL);
3435 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 2);
3436 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3437 view[0] == 0xff && view[1] == 0x10);
3443 // Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL
3444 // General-Dynamic to an Initial-Exec.
3447 Target_i386::Relocate::tls_desc_gd_to_ie(
3448 const Relocate_info<32, false>* relinfo,
3450 const elfcpp::Rel<32, false>& rel,
3451 unsigned int r_type,
3452 elfcpp::Elf_types<32>::Elf_Addr value,
3453 unsigned char* view,
3454 section_size_type view_size)
3456 if (r_type == elfcpp::R_386_TLS_GOTDESC)
3458 // leal foo@TLSDESC(%ebx), %eax
3459 // ==> movl foo@GOTNTPOFF(%ebx), %eax
3460 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
3461 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4);
3462 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3463 view[-2] == 0x8d && view[-1] == 0x83);
3465 Relocate_functions<32, false>::rel32(view, value);
3469 // call *foo@TLSCALL(%eax)
3471 gold_assert(r_type == elfcpp::R_386_TLS_DESC_CALL);
3472 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 2);
3473 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3474 view[0] == 0xff && view[1] == 0x10);
3480 // Do a relocation in which we convert a TLS Local-Dynamic to a
3484 Target_i386::Relocate::tls_ld_to_le(const Relocate_info<32, false>* relinfo,
3487 const elfcpp::Rel<32, false>& rel,
3489 elfcpp::Elf_types<32>::Elf_Addr,
3490 unsigned char* view,
3491 section_size_type view_size)
3493 // leal foo(%reg), %eax; call ___tls_get_addr
3494 // ==> movl %gs:0,%eax; nop; leal 0(%esi,1),%esi
3496 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
3497 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 9);
3499 // FIXME: Does this test really always pass?
3500 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3501 view[-2] == 0x8d && view[-1] == 0x83);
3503 tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[4] == 0xe8);
3505 memcpy(view - 2, "\x65\xa1\0\0\0\0\x90\x8d\x74\x26\0", 11);
3507 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3509 this->skip_call_tls_get_addr_ = true;
3512 // Do a relocation in which we convert a TLS Initial-Exec to a
3516 Target_i386::Relocate::tls_ie_to_le(const Relocate_info<32, false>* relinfo,
3518 Output_segment* tls_segment,
3519 const elfcpp::Rel<32, false>& rel,
3520 unsigned int r_type,
3521 elfcpp::Elf_types<32>::Elf_Addr value,
3522 unsigned char* view,
3523 section_size_type view_size)
3525 // We have to actually change the instructions, which means that we
3526 // need to examine the opcodes to figure out which instruction we
3528 if (r_type == elfcpp::R_386_TLS_IE)
3530 // movl %gs:XX,%eax ==> movl $YY,%eax
3531 // movl %gs:XX,%reg ==> movl $YY,%reg
3532 // addl %gs:XX,%reg ==> addl $YY,%reg
3533 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -1);
3534 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4);
3536 unsigned char op1 = view[-1];
3539 // movl XX,%eax ==> movl $YY,%eax
3544 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
3546 unsigned char op2 = view[-2];
3549 // movl XX,%reg ==> movl $YY,%reg
3550 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3551 (op1 & 0xc7) == 0x05);
3553 view[-1] = 0xc0 | ((op1 >> 3) & 7);
3555 else if (op2 == 0x03)
3557 // addl XX,%reg ==> addl $YY,%reg
3558 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3559 (op1 & 0xc7) == 0x05);
3561 view[-1] = 0xc0 | ((op1 >> 3) & 7);
3564 tls::check_tls(relinfo, relnum, rel.get_r_offset(), 0);
3569 // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2
3570 // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2
3571 // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2
3572 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
3573 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4);
3575 unsigned char op1 = view[-1];
3576 unsigned char op2 = view[-2];
3577 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3578 (op1 & 0xc0) == 0x80 && (op1 & 7) != 4);
3581 // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2
3583 view[-1] = 0xc0 | ((op1 >> 3) & 7);
3585 else if (op2 == 0x2b)
3587 // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2
3589 view[-1] = 0xe8 | ((op1 >> 3) & 7);
3591 else if (op2 == 0x03)
3593 // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2
3595 view[-1] = 0xc0 | ((op1 >> 3) & 7);
3598 tls::check_tls(relinfo, relnum, rel.get_r_offset(), 0);
3601 value = tls_segment->memsz() - value;
3602 if (r_type == elfcpp::R_386_TLS_IE || r_type == elfcpp::R_386_TLS_GOTIE)
3605 Relocate_functions<32, false>::rel32(view, value);
3608 // Relocate section data.
3611 Target_i386::relocate_section(const Relocate_info<32, false>* relinfo,
3612 unsigned int sh_type,
3613 const unsigned char* prelocs,
3615 Output_section* output_section,
3616 bool needs_special_offset_handling,
3617 unsigned char* view,
3618 elfcpp::Elf_types<32>::Elf_Addr address,
3619 section_size_type view_size,
3620 const Reloc_symbol_changes* reloc_symbol_changes)
3622 gold_assert(sh_type == elfcpp::SHT_REL);
3624 gold::relocate_section<32, false, Target_i386, Relocate,
3625 gold::Default_comdat_behavior, Classify_reloc>(
3631 needs_special_offset_handling,
3635 reloc_symbol_changes);
3638 // Return the size of a relocation while scanning during a relocatable
3642 Target_i386::Classify_reloc::get_size_for_reloc(
3643 unsigned int r_type,
3648 case elfcpp::R_386_NONE:
3649 case elfcpp::R_386_GNU_VTINHERIT:
3650 case elfcpp::R_386_GNU_VTENTRY:
3651 case elfcpp::R_386_TLS_GD: // Global-dynamic
3652 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url)
3653 case elfcpp::R_386_TLS_DESC_CALL:
3654 case elfcpp::R_386_TLS_LDM: // Local-dynamic
3655 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
3656 case elfcpp::R_386_TLS_IE: // Initial-exec
3657 case elfcpp::R_386_TLS_IE_32:
3658 case elfcpp::R_386_TLS_GOTIE:
3659 case elfcpp::R_386_TLS_LE: // Local-exec
3660 case elfcpp::R_386_TLS_LE_32:
3663 case elfcpp::R_386_32:
3664 case elfcpp::R_386_PC32:
3665 case elfcpp::R_386_GOT32:
3666 case elfcpp::R_386_GOT32X:
3667 case elfcpp::R_386_PLT32:
3668 case elfcpp::R_386_GOTOFF:
3669 case elfcpp::R_386_GOTPC:
3672 case elfcpp::R_386_16:
3673 case elfcpp::R_386_PC16:
3676 case elfcpp::R_386_8:
3677 case elfcpp::R_386_PC8:
3680 // These are relocations which should only be seen by the
3681 // dynamic linker, and should never be seen here.
3682 case elfcpp::R_386_COPY:
3683 case elfcpp::R_386_GLOB_DAT:
3684 case elfcpp::R_386_JUMP_SLOT:
3685 case elfcpp::R_386_RELATIVE:
3686 case elfcpp::R_386_IRELATIVE:
3687 case elfcpp::R_386_TLS_TPOFF:
3688 case elfcpp::R_386_TLS_DTPMOD32:
3689 case elfcpp::R_386_TLS_DTPOFF32:
3690 case elfcpp::R_386_TLS_TPOFF32:
3691 case elfcpp::R_386_TLS_DESC:
3692 object->error(_("unexpected reloc %u in object file"), r_type);
3695 case elfcpp::R_386_32PLT:
3696 case elfcpp::R_386_TLS_GD_32:
3697 case elfcpp::R_386_TLS_GD_PUSH:
3698 case elfcpp::R_386_TLS_GD_CALL:
3699 case elfcpp::R_386_TLS_GD_POP:
3700 case elfcpp::R_386_TLS_LDM_32:
3701 case elfcpp::R_386_TLS_LDM_PUSH:
3702 case elfcpp::R_386_TLS_LDM_CALL:
3703 case elfcpp::R_386_TLS_LDM_POP:
3704 case elfcpp::R_386_USED_BY_INTEL_200:
3706 object->error(_("unsupported reloc %u in object file"), r_type);
3711 // Scan the relocs during a relocatable link.
3714 Target_i386::scan_relocatable_relocs(Symbol_table* symtab,
3716 Sized_relobj_file<32, false>* object,
3717 unsigned int data_shndx,
3718 unsigned int sh_type,
3719 const unsigned char* prelocs,
3721 Output_section* output_section,
3722 bool needs_special_offset_handling,
3723 size_t local_symbol_count,
3724 const unsigned char* plocal_symbols,
3725 Relocatable_relocs* rr)
3727 typedef gold::Default_scan_relocatable_relocs<Classify_reloc>
3728 Scan_relocatable_relocs;
3730 gold_assert(sh_type == elfcpp::SHT_REL);
3732 gold::scan_relocatable_relocs<32, false, Scan_relocatable_relocs>(
3740 needs_special_offset_handling,
3746 // Scan the relocs for --emit-relocs.
3749 Target_i386::emit_relocs_scan(Symbol_table* symtab,
3751 Sized_relobj_file<32, false>* object,
3752 unsigned int data_shndx,
3753 unsigned int sh_type,
3754 const unsigned char* prelocs,
3756 Output_section* output_section,
3757 bool needs_special_offset_handling,
3758 size_t local_symbol_count,
3759 const unsigned char* plocal_syms,
3760 Relocatable_relocs* rr)
3762 typedef gold::Default_classify_reloc<elfcpp::SHT_REL, 32, false>
3764 typedef gold::Default_emit_relocs_strategy<Classify_reloc>
3765 Emit_relocs_strategy;
3767 gold_assert(sh_type == elfcpp::SHT_REL);
3769 gold::scan_relocatable_relocs<32, false, Emit_relocs_strategy>(
3777 needs_special_offset_handling,
3783 // Emit relocations for a section.
3786 Target_i386::relocate_relocs(
3787 const Relocate_info<32, false>* relinfo,
3788 unsigned int sh_type,
3789 const unsigned char* prelocs,
3791 Output_section* output_section,
3792 elfcpp::Elf_types<32>::Elf_Off offset_in_output_section,
3793 unsigned char* view,
3794 elfcpp::Elf_types<32>::Elf_Addr view_address,
3795 section_size_type view_size,
3796 unsigned char* reloc_view,
3797 section_size_type reloc_view_size)
3799 gold_assert(sh_type == elfcpp::SHT_REL);
3801 gold::relocate_relocs<32, false, Classify_reloc>(
3806 offset_in_output_section,
3814 // Return the value to use for a dynamic which requires special
3815 // treatment. This is how we support equality comparisons of function
3816 // pointers across shared library boundaries, as described in the
3817 // processor specific ABI supplement.
3820 Target_i386::do_dynsym_value(const Symbol* gsym) const
3822 gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset());
3823 return this->plt_address_for_global(gsym);
3826 // Return a string used to fill a code section with nops to take up
3827 // the specified length.
3830 Target_i386::do_code_fill(section_size_type length) const
3834 // Build a jmp instruction to skip over the bytes.
3835 unsigned char jmp[5];
3837 elfcpp::Swap_unaligned<32, false>::writeval(jmp + 1, length - 5);
3838 return (std::string(reinterpret_cast<char*>(&jmp[0]), 5)
3839 + std::string(length - 5, static_cast<char>(0x90)));
3842 // Nop sequences of various lengths.
3843 const char nop1[1] = { '\x90' }; // nop
3844 const char nop2[2] = { '\x66', '\x90' }; // xchg %ax %ax
3845 const char nop3[3] = { '\x8d', '\x76', '\x00' }; // leal 0(%esi),%esi
3846 const char nop4[4] = { '\x8d', '\x74', '\x26', // leal 0(%esi,1),%esi
3848 const char nop5[5] = { '\x90', '\x8d', '\x74', // nop
3849 '\x26', '\x00' }; // leal 0(%esi,1),%esi
3850 const char nop6[6] = { '\x8d', '\xb6', '\x00', // leal 0L(%esi),%esi
3851 '\x00', '\x00', '\x00' };
3852 const char nop7[7] = { '\x8d', '\xb4', '\x26', // leal 0L(%esi,1),%esi
3853 '\x00', '\x00', '\x00',
3855 const char nop8[8] = { '\x90', '\x8d', '\xb4', // nop
3856 '\x26', '\x00', '\x00', // leal 0L(%esi,1),%esi
3858 const char nop9[9] = { '\x89', '\xf6', '\x8d', // movl %esi,%esi
3859 '\xbc', '\x27', '\x00', // leal 0L(%edi,1),%edi
3860 '\x00', '\x00', '\x00' };
3861 const char nop10[10] = { '\x8d', '\x76', '\x00', // leal 0(%esi),%esi
3862 '\x8d', '\xbc', '\x27', // leal 0L(%edi,1),%edi
3863 '\x00', '\x00', '\x00',
3865 const char nop11[11] = { '\x8d', '\x74', '\x26', // leal 0(%esi,1),%esi
3866 '\x00', '\x8d', '\xbc', // leal 0L(%edi,1),%edi
3867 '\x27', '\x00', '\x00',
3869 const char nop12[12] = { '\x8d', '\xb6', '\x00', // leal 0L(%esi),%esi
3870 '\x00', '\x00', '\x00', // leal 0L(%edi),%edi
3871 '\x8d', '\xbf', '\x00',
3872 '\x00', '\x00', '\x00' };
3873 const char nop13[13] = { '\x8d', '\xb6', '\x00', // leal 0L(%esi),%esi
3874 '\x00', '\x00', '\x00', // leal 0L(%edi,1),%edi
3875 '\x8d', '\xbc', '\x27',
3876 '\x00', '\x00', '\x00',
3878 const char nop14[14] = { '\x8d', '\xb4', '\x26', // leal 0L(%esi,1),%esi
3879 '\x00', '\x00', '\x00', // leal 0L(%edi,1),%edi
3880 '\x00', '\x8d', '\xbc',
3881 '\x27', '\x00', '\x00',
3883 const char nop15[15] = { '\xeb', '\x0d', '\x90', // jmp .+15
3884 '\x90', '\x90', '\x90', // nop,nop,nop,...
3885 '\x90', '\x90', '\x90',
3886 '\x90', '\x90', '\x90',
3887 '\x90', '\x90', '\x90' };
3889 const char* nops[16] = {
3891 nop1, nop2, nop3, nop4, nop5, nop6, nop7,
3892 nop8, nop9, nop10, nop11, nop12, nop13, nop14, nop15
3895 return std::string(nops[length], length);
3898 // Return the value to use for the base of a DW_EH_PE_datarel offset
3899 // in an FDE. Solaris and SVR4 use DW_EH_PE_datarel because their
3900 // assembler can not write out the difference between two labels in
3901 // different sections, so instead of using a pc-relative value they
3902 // use an offset from the GOT.
3905 Target_i386::do_ehframe_datarel_base() const
3907 gold_assert(this->global_offset_table_ != NULL);
3908 Symbol* sym = this->global_offset_table_;
3909 Sized_symbol<32>* ssym = static_cast<Sized_symbol<32>*>(sym);
3910 return ssym->value();
3913 // Return whether SYM should be treated as a call to a non-split
3914 // function. We don't want that to be true of a call to a
3915 // get_pc_thunk function.
3918 Target_i386::do_is_call_to_non_split(const Symbol* sym,
3919 const unsigned char*) const
3921 return (sym->type() == elfcpp::STT_FUNC
3922 && !is_prefix_of("__i686.get_pc_thunk.", sym->name()));
3925 // FNOFFSET in section SHNDX in OBJECT is the start of a function
3926 // compiled with -fsplit-stack. The function calls non-split-stack
3927 // code. We have to change the function so that it always ensures
3928 // that it has enough stack space to run some random function.
3931 Target_i386::do_calls_non_split(Relobj* object, unsigned int shndx,
3932 section_offset_type fnoffset,
3933 section_size_type fnsize,
3934 const unsigned char*,
3936 unsigned char* view,
3937 section_size_type view_size,
3939 std::string* to) const
3941 // The function starts with a comparison of the stack pointer and a
3942 // field in the TCB. This is followed by a jump.
3945 if (this->match_view(view, view_size, fnoffset, "\x65\x3b\x25", 3)
3948 // We will call __morestack if the carry flag is set after this
3949 // comparison. We turn the comparison into an stc instruction
3951 view[fnoffset] = '\xf9';
3952 this->set_view_to_nop(view, view_size, fnoffset + 1, 6);
3954 // lea NN(%esp),%ecx
3955 // lea NN(%esp),%edx
3956 else if ((this->match_view(view, view_size, fnoffset, "\x8d\x8c\x24", 3)
3957 || this->match_view(view, view_size, fnoffset, "\x8d\x94\x24", 3))
3960 // This is loading an offset from the stack pointer for a
3961 // comparison. The offset is negative, so we decrease the
3962 // offset by the amount of space we need for the stack. This
3963 // means we will avoid calling __morestack if there happens to
3964 // be plenty of space on the stack already.
3965 unsigned char* pval = view + fnoffset + 3;
3966 uint32_t val = elfcpp::Swap_unaligned<32, false>::readval(pval);
3967 val -= parameters->options().split_stack_adjust_size();
3968 elfcpp::Swap_unaligned<32, false>::writeval(pval, val);
3972 if (!object->has_no_split_stack())
3973 object->error(_("failed to match split-stack sequence at "
3974 "section %u offset %0zx"),
3975 shndx, static_cast<size_t>(fnoffset));
3979 // We have to change the function so that it calls
3980 // __morestack_non_split instead of __morestack. The former will
3981 // allocate additional stack space.
3982 *from = "__morestack";
3983 *to = "__morestack_non_split";
3986 // The selector for i386 object files. Note this is never instantiated
3987 // directly. It's only used in Target_selector_i386_nacl, below.
3989 class Target_selector_i386 : public Target_selector_freebsd
3992 Target_selector_i386()
3993 : Target_selector_freebsd(elfcpp::EM_386, 32, false,
3994 "elf32-i386", "elf32-i386-freebsd",
3999 do_instantiate_target()
4000 { return new Target_i386(); }
4003 // NaCl variant. It uses different PLT contents.
4005 class Output_data_plt_i386_nacl : public Output_data_plt_i386
4008 Output_data_plt_i386_nacl(Layout* layout,
4009 Output_data_got_plt_i386* got_plt,
4010 Output_data_space* got_irelative)
4011 : Output_data_plt_i386(layout, plt_entry_size, got_plt, got_irelative)
4015 virtual unsigned int
4016 do_get_plt_entry_size() const
4017 { return plt_entry_size; }
4020 do_add_eh_frame(Layout* layout)
4022 layout->add_eh_frame_for_plt(this, plt_eh_frame_cie, plt_eh_frame_cie_size,
4023 plt_eh_frame_fde, plt_eh_frame_fde_size);
4026 // The size of an entry in the PLT.
4027 static const int plt_entry_size = 64;
4029 // The .eh_frame unwind information for the PLT.
4030 static const int plt_eh_frame_fde_size = 32;
4031 static const unsigned char plt_eh_frame_fde[plt_eh_frame_fde_size];
4034 class Output_data_plt_i386_nacl_exec : public Output_data_plt_i386_nacl
4037 Output_data_plt_i386_nacl_exec(Layout* layout,
4038 Output_data_got_plt_i386* got_plt,
4039 Output_data_space* got_irelative)
4040 : Output_data_plt_i386_nacl(layout, got_plt, got_irelative)
4045 do_fill_first_plt_entry(unsigned char* pov,
4046 elfcpp::Elf_types<32>::Elf_Addr got_address);
4048 virtual unsigned int
4049 do_fill_plt_entry(unsigned char* pov,
4050 elfcpp::Elf_types<32>::Elf_Addr got_address,
4051 unsigned int got_offset,
4052 unsigned int plt_offset,
4053 unsigned int plt_rel_offset);
4056 // The first entry in the PLT for an executable.
4057 static const unsigned char first_plt_entry[plt_entry_size];
4059 // Other entries in the PLT for an executable.
4060 static const unsigned char plt_entry[plt_entry_size];
4063 class Output_data_plt_i386_nacl_dyn : public Output_data_plt_i386_nacl
4066 Output_data_plt_i386_nacl_dyn(Layout* layout,
4067 Output_data_got_plt_i386* got_plt,
4068 Output_data_space* got_irelative)
4069 : Output_data_plt_i386_nacl(layout, got_plt, got_irelative)
4074 do_fill_first_plt_entry(unsigned char* pov, elfcpp::Elf_types<32>::Elf_Addr);
4076 virtual unsigned int
4077 do_fill_plt_entry(unsigned char* pov,
4078 elfcpp::Elf_types<32>::Elf_Addr,
4079 unsigned int got_offset,
4080 unsigned int plt_offset,
4081 unsigned int plt_rel_offset);
4084 // The first entry in the PLT for a shared object.
4085 static const unsigned char first_plt_entry[plt_entry_size];
4087 // Other entries in the PLT for a shared object.
4088 static const unsigned char plt_entry[plt_entry_size];
4091 class Target_i386_nacl : public Target_i386
4095 : Target_i386(&i386_nacl_info)
4099 virtual Output_data_plt_i386*
4100 do_make_data_plt(Layout* layout,
4101 Output_data_got_plt_i386* got_plt,
4102 Output_data_space* got_irelative,
4106 return new Output_data_plt_i386_nacl_dyn(layout, got_plt, got_irelative);
4108 return new Output_data_plt_i386_nacl_exec(layout, got_plt, got_irelative);
4112 do_code_fill(section_size_type length) const;
4115 static const Target::Target_info i386_nacl_info;
4118 const Target::Target_info Target_i386_nacl::i386_nacl_info =
4121 false, // is_big_endian
4122 elfcpp::EM_386, // machine_code
4123 false, // has_make_symbol
4124 false, // has_resolve
4125 true, // has_code_fill
4126 true, // is_default_stack_executable
4127 true, // can_icf_inline_merge_sections
4129 "/lib/ld-nacl-x86-32.so.1", // dynamic_linker
4130 0x20000, // default_text_segment_address
4131 0x10000, // abi_pagesize (overridable by -z max-page-size)
4132 0x10000, // common_pagesize (overridable by -z common-page-size)
4133 true, // isolate_execinstr
4134 0x10000000, // rosegment_gap
4135 elfcpp::SHN_UNDEF, // small_common_shndx
4136 elfcpp::SHN_UNDEF, // large_common_shndx
4137 0, // small_common_section_flags
4138 0, // large_common_section_flags
4139 NULL, // attributes_section
4140 NULL, // attributes_vendor
4141 "_start", // entry_symbol_name
4142 32, // hash_entry_size
4145 #define NACLMASK 0xe0 // 32-byte alignment mask
4148 Output_data_plt_i386_nacl_exec::first_plt_entry[plt_entry_size] =
4150 0xff, 0x35, // pushl contents of memory address
4151 0, 0, 0, 0, // replaced with address of .got + 4
4152 0x8b, 0x0d, // movl contents of address, %ecx
4153 0, 0, 0, 0, // replaced with address of .got + 8
4154 0x83, 0xe1, NACLMASK, // andl $NACLMASK, %ecx
4155 0xff, 0xe1, // jmp *%ecx
4156 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4157 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4158 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4159 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4160 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4161 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4162 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4163 0x90, 0x90, 0x90, 0x90, 0x90
4167 Output_data_plt_i386_nacl_exec::do_fill_first_plt_entry(
4169 elfcpp::Elf_types<32>::Elf_Addr got_address)
4171 memcpy(pov, first_plt_entry, plt_entry_size);
4172 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_address + 4);
4173 elfcpp::Swap<32, false>::writeval(pov + 8, got_address + 8);
4176 // The first entry in the PLT for a shared object.
4179 Output_data_plt_i386_nacl_dyn::first_plt_entry[plt_entry_size] =
4181 0xff, 0xb3, 4, 0, 0, 0, // pushl 4(%ebx)
4182 0x8b, 0x4b, 0x08, // mov 0x8(%ebx), %ecx
4183 0x83, 0xe1, NACLMASK, // andl $NACLMASK, %ecx
4184 0xff, 0xe1, // jmp *%ecx
4185 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4186 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4187 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4188 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4189 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4190 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4191 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4192 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4193 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4194 0x90, 0x90, 0x90, 0x90, 0x90 // nops
4198 Output_data_plt_i386_nacl_dyn::do_fill_first_plt_entry(
4200 elfcpp::Elf_types<32>::Elf_Addr)
4202 memcpy(pov, first_plt_entry, plt_entry_size);
4205 // Subsequent entries in the PLT for an executable.
4208 Output_data_plt_i386_nacl_exec::plt_entry[plt_entry_size] =
4210 0x8b, 0x0d, // movl contents of address, %ecx */
4211 0, 0, 0, 0, // replaced with address of symbol in .got
4212 0x83, 0xe1, NACLMASK, // andl $NACLMASK, %ecx
4213 0xff, 0xe1, // jmp *%ecx
4215 // Pad to the next 32-byte boundary with nop instructions.
4217 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4218 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4220 // Lazy GOT entries point here (32-byte aligned).
4221 0x68, // pushl immediate
4222 0, 0, 0, 0, // replaced with offset into relocation table
4223 0xe9, // jmp relative
4224 0, 0, 0, 0, // replaced with offset to start of .plt
4226 // Pad to the next 32-byte boundary with nop instructions.
4227 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4228 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4233 Output_data_plt_i386_nacl_exec::do_fill_plt_entry(
4235 elfcpp::Elf_types<32>::Elf_Addr got_address,
4236 unsigned int got_offset,
4237 unsigned int plt_offset,
4238 unsigned int plt_rel_offset)
4240 memcpy(pov, plt_entry, plt_entry_size);
4241 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
4242 got_address + got_offset);
4243 elfcpp::Swap_unaligned<32, false>::writeval(pov + 33, plt_rel_offset);
4244 elfcpp::Swap<32, false>::writeval(pov + 38, - (plt_offset + 38 + 4));
4248 // Subsequent entries in the PLT for a shared object.
4251 Output_data_plt_i386_nacl_dyn::plt_entry[plt_entry_size] =
4253 0x8b, 0x8b, // movl offset(%ebx), %ecx
4254 0, 0, 0, 0, // replaced with offset of symbol in .got
4255 0x83, 0xe1, 0xe0, // andl $NACLMASK, %ecx
4256 0xff, 0xe1, // jmp *%ecx
4258 // Pad to the next 32-byte boundary with nop instructions.
4260 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4261 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4263 // Lazy GOT entries point here (32-byte aligned).
4264 0x68, // pushl immediate
4265 0, 0, 0, 0, // replaced with offset into relocation table.
4266 0xe9, // jmp relative
4267 0, 0, 0, 0, // replaced with offset to start of .plt.
4269 // Pad to the next 32-byte boundary with nop instructions.
4270 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4271 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4276 Output_data_plt_i386_nacl_dyn::do_fill_plt_entry(
4278 elfcpp::Elf_types<32>::Elf_Addr,
4279 unsigned int got_offset,
4280 unsigned int plt_offset,
4281 unsigned int plt_rel_offset)
4283 memcpy(pov, plt_entry, plt_entry_size);
4284 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_offset);
4285 elfcpp::Swap_unaligned<32, false>::writeval(pov + 33, plt_rel_offset);
4286 elfcpp::Swap<32, false>::writeval(pov + 38, - (plt_offset + 38 + 4));
4291 Output_data_plt_i386_nacl::plt_eh_frame_fde[plt_eh_frame_fde_size] =
4293 0, 0, 0, 0, // Replaced with offset to .plt.
4294 0, 0, 0, 0, // Replaced with size of .plt.
4295 0, // Augmentation size.
4296 elfcpp::DW_CFA_def_cfa_offset, 8, // DW_CFA_def_cfa_offset: 8.
4297 elfcpp::DW_CFA_advance_loc + 6, // Advance 6 to __PLT__ + 6.
4298 elfcpp::DW_CFA_def_cfa_offset, 12, // DW_CFA_def_cfa_offset: 12.
4299 elfcpp::DW_CFA_advance_loc + 58, // Advance 58 to __PLT__ + 64.
4300 elfcpp::DW_CFA_def_cfa_expression, // DW_CFA_def_cfa_expression.
4301 13, // Block length.
4302 elfcpp::DW_OP_breg4, 4, // Push %esp + 4.
4303 elfcpp::DW_OP_breg8, 0, // Push %eip.
4304 elfcpp::DW_OP_const1u, 63, // Push 0x3f.
4305 elfcpp::DW_OP_and, // & (%eip & 0x3f).
4306 elfcpp::DW_OP_const1u, 37, // Push 0x25.
4307 elfcpp::DW_OP_ge, // >= ((%eip & 0x3f) >= 0x25)
4308 elfcpp::DW_OP_lit2, // Push 2.
4309 elfcpp::DW_OP_shl, // << (((%eip & 0x3f) >= 0x25) << 2)
4310 elfcpp::DW_OP_plus, // + ((((%eip&0x3f)>=0x25)<<2)+%esp+4
4311 elfcpp::DW_CFA_nop, // Align to 32 bytes.
4315 // Return a string used to fill a code section with nops.
4316 // For NaCl, long NOPs are only valid if they do not cross
4317 // bundle alignment boundaries, so keep it simple with one-byte NOPs.
4319 Target_i386_nacl::do_code_fill(section_size_type length) const
4321 return std::string(length, static_cast<char>(0x90));
4324 // The selector for i386-nacl object files.
4326 class Target_selector_i386_nacl
4327 : public Target_selector_nacl<Target_selector_i386, Target_i386_nacl>
4330 Target_selector_i386_nacl()
4331 : Target_selector_nacl<Target_selector_i386,
4332 Target_i386_nacl>("x86-32",
4338 Target_selector_i386_nacl target_selector_i386;
4340 // IAMCU variant. It uses EM_IAMCU, not EM_386.
4342 class Target_iamcu : public Target_i386
4346 : Target_i386(&iamcu_info)
4350 // Information about this specific target which we pass to the
4351 // general Target structure.
4352 static const Target::Target_info iamcu_info;
4355 const Target::Target_info Target_iamcu::iamcu_info =
4358 false, // is_big_endian
4359 elfcpp::EM_IAMCU, // machine_code
4360 false, // has_make_symbol
4361 false, // has_resolve
4362 true, // has_code_fill
4363 true, // is_default_stack_executable
4364 true, // can_icf_inline_merge_sections
4366 "/usr/lib/libc.so.1", // dynamic_linker
4367 0x08048000, // default_text_segment_address
4368 0x1000, // abi_pagesize (overridable by -z max-page-size)
4369 0x1000, // common_pagesize (overridable by -z common-page-size)
4370 false, // isolate_execinstr
4372 elfcpp::SHN_UNDEF, // small_common_shndx
4373 elfcpp::SHN_UNDEF, // large_common_shndx
4374 0, // small_common_section_flags
4375 0, // large_common_section_flags
4376 NULL, // attributes_section
4377 NULL, // attributes_vendor
4378 "_start", // entry_symbol_name
4379 32, // hash_entry_size
4382 class Target_selector_iamcu : public Target_selector
4385 Target_selector_iamcu()
4386 : Target_selector(elfcpp::EM_IAMCU, 32, false, "elf32-iamcu",
4391 do_instantiate_target()
4392 { return new Target_iamcu(); }
4395 Target_selector_iamcu target_selector_iamcu;
4397 } // End anonymous namespace.