1 // i386.cc -- i386 target support for gold.
3 // Copyright 2006, 2007, 2008, 2009, 2010, 2011 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"
49 // A class to handle the PLT data.
51 class Output_data_plt_i386 : public Output_section_data
54 typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, false> Reloc_section;
56 Output_data_plt_i386(Layout*, Output_data_space*, Output_data_space*);
58 // Add an entry to the PLT.
60 add_entry(Symbol_table*, Layout*, Symbol* gsym);
62 // Add an entry to the PLT for a local STT_GNU_IFUNC symbol.
64 add_local_ifunc_entry(Symbol_table*, Layout*,
65 Sized_relobj_file<32, false>* relobj,
66 unsigned int local_sym_index);
68 // Return the .rel.plt section data.
71 { return this->rel_; }
73 // Return where the TLS_DESC relocations should go.
75 rel_tls_desc(Layout*);
77 // Return where the IRELATIVE relocations should go.
79 rel_irelative(Symbol_table*, Layout*);
81 // Return whether we created a section for IRELATIVE relocations.
83 has_irelative_section() const
84 { return this->irelative_rel_ != NULL; }
86 // Return the number of PLT entries.
89 { return this->count_ + this->irelative_count_; }
91 // Return the offset of the first non-reserved PLT entry.
93 first_plt_entry_offset()
94 { return plt_entry_size; }
96 // Return the size of a PLT entry.
99 { return plt_entry_size; }
101 // Return the PLT address to use for a global symbol.
103 address_for_global(const Symbol*);
105 // Return the PLT address to use for a local symbol.
107 address_for_local(const Relobj*, unsigned int symndx);
111 do_adjust_output_section(Output_section* os);
113 // Write to a map file.
115 do_print_to_mapfile(Mapfile* mapfile) const
116 { mapfile->print_output_data(this, _("** PLT")); }
119 // The size of an entry in the PLT.
120 static const int plt_entry_size = 16;
122 // The first entry in the PLT for an executable.
123 static const unsigned char exec_first_plt_entry[plt_entry_size];
125 // The first entry in the PLT for a shared object.
126 static const unsigned char dyn_first_plt_entry[plt_entry_size];
128 // Other entries in the PLT for an executable.
129 static const unsigned char exec_plt_entry[plt_entry_size];
131 // Other entries in the PLT for a shared object.
132 static const unsigned char dyn_plt_entry[plt_entry_size];
134 // The .eh_frame unwind information for the PLT.
135 static const int plt_eh_frame_cie_size = 16;
136 static const int plt_eh_frame_fde_size = 32;
137 static const unsigned char plt_eh_frame_cie[plt_eh_frame_cie_size];
138 static const unsigned char plt_eh_frame_fde[plt_eh_frame_fde_size];
140 // Set the final size.
142 set_final_data_size()
144 this->set_data_size((this->count_ + this->irelative_count_ + 1)
148 // Write out the PLT data.
150 do_write(Output_file*);
152 // We keep a list of global STT_GNU_IFUNC symbols, each with its
153 // offset in the GOT.
157 unsigned int got_offset;
160 // We keep a list of local STT_GNU_IFUNC symbols, each with its
161 // offset in the GOT.
164 Sized_relobj_file<32, false>* object;
165 unsigned int local_sym_index;
166 unsigned int got_offset;
169 // The reloc section.
171 // The TLS_DESC relocations, if necessary. These must follow the
172 // regular PLT relocs.
173 Reloc_section* tls_desc_rel_;
174 // The IRELATIVE relocations, if necessary. These must follow the
175 // regular relocatoins and the TLS_DESC relocations.
176 Reloc_section* irelative_rel_;
177 // The .got.plt section.
178 Output_data_space* got_plt_;
179 // The part of the .got.plt section used for IRELATIVE relocs.
180 Output_data_space* got_irelative_;
181 // The number of PLT entries.
183 // Number of PLT entries with R_386_IRELATIVE relocs. These follow
184 // the regular PLT entries.
185 unsigned int irelative_count_;
186 // Global STT_GNU_IFUNC symbols.
187 std::vector<Global_ifunc> global_ifuncs_;
188 // Local STT_GNU_IFUNC symbols.
189 std::vector<Local_ifunc> local_ifuncs_;
192 // The i386 target class.
193 // TLS info comes from
194 // http://people.redhat.com/drepper/tls.pdf
195 // http://www.lsd.ic.unicamp.br/~oliva/writeups/TLS/RFC-TLSDESC-x86.txt
197 class Target_i386 : public Sized_target<32, false>
200 typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, false> Reloc_section;
203 : Sized_target<32, false>(&i386_info),
204 got_(NULL), plt_(NULL), got_plt_(NULL), got_irelative_(NULL),
205 got_tlsdesc_(NULL), global_offset_table_(NULL), rel_dyn_(NULL),
206 rel_irelative_(NULL), copy_relocs_(elfcpp::R_386_COPY), dynbss_(NULL),
207 got_mod_index_offset_(-1U), tls_base_symbol_defined_(false)
210 // Process the relocations to determine unreferenced sections for
211 // garbage collection.
213 gc_process_relocs(Symbol_table* symtab,
215 Sized_relobj_file<32, false>* object,
216 unsigned int data_shndx,
217 unsigned int sh_type,
218 const unsigned char* prelocs,
220 Output_section* output_section,
221 bool needs_special_offset_handling,
222 size_t local_symbol_count,
223 const unsigned char* plocal_symbols);
225 // Scan the relocations to look for symbol adjustments.
227 scan_relocs(Symbol_table* symtab,
229 Sized_relobj_file<32, false>* object,
230 unsigned int data_shndx,
231 unsigned int sh_type,
232 const unsigned char* prelocs,
234 Output_section* output_section,
235 bool needs_special_offset_handling,
236 size_t local_symbol_count,
237 const unsigned char* plocal_symbols);
239 // Finalize the sections.
241 do_finalize_sections(Layout*, const Input_objects*, Symbol_table*);
243 // Return the value to use for a dynamic which requires special
246 do_dynsym_value(const Symbol*) const;
248 // Relocate a section.
250 relocate_section(const Relocate_info<32, false>*,
251 unsigned int sh_type,
252 const unsigned char* prelocs,
254 Output_section* output_section,
255 bool needs_special_offset_handling,
257 elfcpp::Elf_types<32>::Elf_Addr view_address,
258 section_size_type view_size,
259 const Reloc_symbol_changes*);
261 // Scan the relocs during a relocatable link.
263 scan_relocatable_relocs(Symbol_table* symtab,
265 Sized_relobj_file<32, false>* object,
266 unsigned int data_shndx,
267 unsigned int sh_type,
268 const unsigned char* prelocs,
270 Output_section* output_section,
271 bool needs_special_offset_handling,
272 size_t local_symbol_count,
273 const unsigned char* plocal_symbols,
274 Relocatable_relocs*);
276 // Relocate a section during a relocatable link.
278 relocate_for_relocatable(const Relocate_info<32, false>*,
279 unsigned int sh_type,
280 const unsigned char* prelocs,
282 Output_section* output_section,
283 off_t offset_in_output_section,
284 const Relocatable_relocs*,
286 elfcpp::Elf_types<32>::Elf_Addr view_address,
287 section_size_type view_size,
288 unsigned char* reloc_view,
289 section_size_type reloc_view_size);
291 // Return a string used to fill a code section with nops.
293 do_code_fill(section_size_type length) const;
295 // Return whether SYM is defined by the ABI.
297 do_is_defined_by_abi(const Symbol* sym) const
298 { return strcmp(sym->name(), "___tls_get_addr") == 0; }
300 // Return whether a symbol name implies a local label. The UnixWare
301 // 2.1 cc generates temporary symbols that start with .X, so we
302 // recognize them here. FIXME: do other SVR4 compilers also use .X?.
303 // If so, we should move the .X recognition into
304 // Target::do_is_local_label_name.
306 do_is_local_label_name(const char* name) const
308 if (name[0] == '.' && name[1] == 'X')
310 return Target::do_is_local_label_name(name);
313 // Return the PLT address to use for a global symbol.
315 do_plt_address_for_global(const Symbol* gsym) const
316 { return this->plt_section()->address_for_global(gsym); }
319 do_plt_address_for_local(const Relobj* relobj, unsigned int symndx) const
320 { return this->plt_section()->address_for_local(relobj, symndx); }
322 // We can tell whether we take the address of a function.
324 do_can_check_for_function_pointers() const
327 // Return the base for a DW_EH_PE_datarel encoding.
329 do_ehframe_datarel_base() const;
331 // Return whether SYM is call to a non-split function.
333 do_is_call_to_non_split(const Symbol* sym, unsigned int) const;
335 // Adjust -fsplit-stack code which calls non-split-stack code.
337 do_calls_non_split(Relobj* object, unsigned int shndx,
338 section_offset_type fnoffset, section_size_type fnsize,
339 unsigned char* view, section_size_type view_size,
340 std::string* from, std::string* to) const;
342 // Return the size of the GOT section.
346 gold_assert(this->got_ != NULL);
347 return this->got_->data_size();
350 // Return the number of entries in the GOT.
352 got_entry_count() const
354 if (this->got_ == NULL)
356 return this->got_size() / 4;
359 // Return the number of entries in the PLT.
361 plt_entry_count() const;
363 // Return the offset of the first non-reserved PLT entry.
365 first_plt_entry_offset() const;
367 // Return the size of each PLT entry.
369 plt_entry_size() const;
372 // The class which scans relocations.
377 get_reference_flags(unsigned int r_type);
380 local(Symbol_table* symtab, Layout* layout, Target_i386* target,
381 Sized_relobj_file<32, false>* object,
382 unsigned int data_shndx,
383 Output_section* output_section,
384 const elfcpp::Rel<32, false>& reloc, unsigned int r_type,
385 const elfcpp::Sym<32, false>& lsym);
388 global(Symbol_table* symtab, Layout* layout, Target_i386* target,
389 Sized_relobj_file<32, false>* object,
390 unsigned int data_shndx,
391 Output_section* output_section,
392 const elfcpp::Rel<32, false>& reloc, unsigned int r_type,
396 local_reloc_may_be_function_pointer(Symbol_table* symtab, Layout* layout,
398 Sized_relobj_file<32, false>* object,
399 unsigned int data_shndx,
400 Output_section* output_section,
401 const elfcpp::Rel<32, false>& reloc,
403 const elfcpp::Sym<32, false>& lsym);
406 global_reloc_may_be_function_pointer(Symbol_table* symtab, Layout* layout,
408 Sized_relobj_file<32, false>* object,
409 unsigned int data_shndx,
410 Output_section* output_section,
411 const elfcpp::Rel<32, false>& reloc,
416 possible_function_pointer_reloc(unsigned int r_type);
419 reloc_needs_plt_for_ifunc(Sized_relobj_file<32, false>*,
420 unsigned int r_type);
423 unsupported_reloc_local(Sized_relobj_file<32, false>*, unsigned int r_type);
426 unsupported_reloc_global(Sized_relobj_file<32, false>*, unsigned int r_type,
430 // The class which implements relocation.
435 : skip_call_tls_get_addr_(false),
436 local_dynamic_type_(LOCAL_DYNAMIC_NONE)
441 if (this->skip_call_tls_get_addr_)
443 // FIXME: This needs to specify the location somehow.
444 gold_error(_("missing expected TLS relocation"));
448 // Return whether the static relocation needs to be applied.
450 should_apply_static_reloc(const Sized_symbol<32>* gsym,
453 Output_section* output_section);
455 // Do a relocation. Return false if the caller should not issue
456 // any warnings about this relocation.
458 relocate(const Relocate_info<32, false>*, Target_i386*, Output_section*,
459 size_t relnum, const elfcpp::Rel<32, false>&,
460 unsigned int r_type, const Sized_symbol<32>*,
461 const Symbol_value<32>*,
462 unsigned char*, elfcpp::Elf_types<32>::Elf_Addr,
466 // Do a TLS relocation.
468 relocate_tls(const Relocate_info<32, false>*, Target_i386* target,
469 size_t relnum, const elfcpp::Rel<32, false>&,
470 unsigned int r_type, const Sized_symbol<32>*,
471 const Symbol_value<32>*,
472 unsigned char*, elfcpp::Elf_types<32>::Elf_Addr,
475 // Do a TLS General-Dynamic to Initial-Exec transition.
477 tls_gd_to_ie(const Relocate_info<32, false>*, size_t relnum,
478 Output_segment* tls_segment,
479 const elfcpp::Rel<32, false>&, unsigned int r_type,
480 elfcpp::Elf_types<32>::Elf_Addr value,
482 section_size_type view_size);
484 // Do a TLS General-Dynamic to Local-Exec transition.
486 tls_gd_to_le(const Relocate_info<32, false>*, size_t relnum,
487 Output_segment* tls_segment,
488 const elfcpp::Rel<32, false>&, unsigned int r_type,
489 elfcpp::Elf_types<32>::Elf_Addr value,
491 section_size_type view_size);
493 // Do a TLS_GOTDESC or TLS_DESC_CALL General-Dynamic to Initial-Exec
496 tls_desc_gd_to_ie(const Relocate_info<32, false>*, size_t relnum,
497 Output_segment* tls_segment,
498 const elfcpp::Rel<32, false>&, unsigned int r_type,
499 elfcpp::Elf_types<32>::Elf_Addr value,
501 section_size_type view_size);
503 // Do a TLS_GOTDESC or TLS_DESC_CALL General-Dynamic to Local-Exec
506 tls_desc_gd_to_le(const Relocate_info<32, false>*, size_t relnum,
507 Output_segment* tls_segment,
508 const elfcpp::Rel<32, false>&, unsigned int r_type,
509 elfcpp::Elf_types<32>::Elf_Addr value,
511 section_size_type view_size);
513 // Do a TLS Local-Dynamic to Local-Exec transition.
515 tls_ld_to_le(const Relocate_info<32, false>*, size_t relnum,
516 Output_segment* tls_segment,
517 const elfcpp::Rel<32, false>&, unsigned int r_type,
518 elfcpp::Elf_types<32>::Elf_Addr value,
520 section_size_type view_size);
522 // Do a TLS Initial-Exec to Local-Exec transition.
524 tls_ie_to_le(const Relocate_info<32, false>*, size_t relnum,
525 Output_segment* tls_segment,
526 const elfcpp::Rel<32, false>&, unsigned int r_type,
527 elfcpp::Elf_types<32>::Elf_Addr value,
529 section_size_type view_size);
531 // We need to keep track of which type of local dynamic relocation
532 // we have seen, so that we can optimize R_386_TLS_LDO_32 correctly.
533 enum Local_dynamic_type
540 // This is set if we should skip the next reloc, which should be a
541 // PLT32 reloc against ___tls_get_addr.
542 bool skip_call_tls_get_addr_;
543 // The type of local dynamic relocation we have seen in the section
544 // being relocated, if any.
545 Local_dynamic_type local_dynamic_type_;
548 // A class which returns the size required for a relocation type,
549 // used while scanning relocs during a relocatable link.
550 class Relocatable_size_for_reloc
554 get_size_for_reloc(unsigned int, Relobj*);
557 // Adjust TLS relocation type based on the options and whether this
558 // is a local symbol.
559 static tls::Tls_optimization
560 optimize_tls_reloc(bool is_final, int r_type);
562 // Get the GOT section, creating it if necessary.
563 Output_data_got<32, false>*
564 got_section(Symbol_table*, Layout*);
566 // Get the GOT PLT section.
568 got_plt_section() const
570 gold_assert(this->got_plt_ != NULL);
571 return this->got_plt_;
574 // Get the GOT section for TLSDESC entries.
575 Output_data_got<32, false>*
576 got_tlsdesc_section() const
578 gold_assert(this->got_tlsdesc_ != NULL);
579 return this->got_tlsdesc_;
582 // Create the PLT section.
584 make_plt_section(Symbol_table* symtab, Layout* layout);
586 // Create a PLT entry for a global symbol.
588 make_plt_entry(Symbol_table*, Layout*, Symbol*);
590 // Create a PLT entry for a local STT_GNU_IFUNC symbol.
592 make_local_ifunc_plt_entry(Symbol_table*, Layout*,
593 Sized_relobj_file<32, false>* relobj,
594 unsigned int local_sym_index);
596 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
598 define_tls_base_symbol(Symbol_table*, Layout*);
600 // Create a GOT entry for the TLS module index.
602 got_mod_index_entry(Symbol_table* symtab, Layout* layout,
603 Sized_relobj_file<32, false>* object);
605 // Get the PLT section.
606 Output_data_plt_i386*
609 gold_assert(this->plt_ != NULL);
613 // Get the dynamic reloc section, creating it if necessary.
615 rel_dyn_section(Layout*);
617 // Get the section to use for TLS_DESC relocations.
619 rel_tls_desc_section(Layout*) const;
621 // Get the section to use for IRELATIVE relocations.
623 rel_irelative_section(Layout*);
625 // Add a potential copy relocation.
627 copy_reloc(Symbol_table* symtab, Layout* layout,
628 Sized_relobj_file<32, false>* object,
629 unsigned int shndx, Output_section* output_section,
630 Symbol* sym, const elfcpp::Rel<32, false>& reloc)
632 this->copy_relocs_.copy_reloc(symtab, layout,
633 symtab->get_sized_symbol<32>(sym),
634 object, shndx, output_section, reloc,
635 this->rel_dyn_section(layout));
638 // Information about this specific target which we pass to the
639 // general Target structure.
640 static const Target::Target_info i386_info;
642 // The types of GOT entries needed for this platform.
643 // These values are exposed to the ABI in an incremental link.
644 // Do not renumber existing values without changing the version
645 // number of the .gnu_incremental_inputs section.
648 GOT_TYPE_STANDARD = 0, // GOT entry for a regular symbol
649 GOT_TYPE_TLS_NOFFSET = 1, // GOT entry for negative TLS offset
650 GOT_TYPE_TLS_OFFSET = 2, // GOT entry for positive TLS offset
651 GOT_TYPE_TLS_PAIR = 3, // GOT entry for TLS module/offset pair
652 GOT_TYPE_TLS_DESC = 4 // GOT entry for TLS_DESC pair
656 Output_data_got<32, false>* got_;
658 Output_data_plt_i386* plt_;
659 // The GOT PLT section.
660 Output_data_space* got_plt_;
661 // The GOT section for IRELATIVE relocations.
662 Output_data_space* got_irelative_;
663 // The GOT section for TLSDESC relocations.
664 Output_data_got<32, false>* got_tlsdesc_;
665 // The _GLOBAL_OFFSET_TABLE_ symbol.
666 Symbol* global_offset_table_;
667 // The dynamic reloc section.
668 Reloc_section* rel_dyn_;
669 // The section to use for IRELATIVE relocs.
670 Reloc_section* rel_irelative_;
671 // Relocs saved to avoid a COPY reloc.
672 Copy_relocs<elfcpp::SHT_REL, 32, false> copy_relocs_;
673 // Space for variables copied with a COPY reloc.
674 Output_data_space* dynbss_;
675 // Offset of the GOT entry for the TLS module index.
676 unsigned int got_mod_index_offset_;
677 // True if the _TLS_MODULE_BASE_ symbol has been defined.
678 bool tls_base_symbol_defined_;
681 const Target::Target_info Target_i386::i386_info =
684 false, // is_big_endian
685 elfcpp::EM_386, // machine_code
686 false, // has_make_symbol
687 false, // has_resolve
688 true, // has_code_fill
689 true, // is_default_stack_executable
690 true, // can_icf_inline_merge_sections
692 "/usr/lib/libc.so.1", // dynamic_linker
693 0x08048000, // default_text_segment_address
694 0x1000, // abi_pagesize (overridable by -z max-page-size)
695 0x1000, // common_pagesize (overridable by -z common-page-size)
696 elfcpp::SHN_UNDEF, // small_common_shndx
697 elfcpp::SHN_UNDEF, // large_common_shndx
698 0, // small_common_section_flags
699 0, // large_common_section_flags
700 NULL, // attributes_section
701 NULL // attributes_vendor
704 // Get the GOT section, creating it if necessary.
706 Output_data_got<32, false>*
707 Target_i386::got_section(Symbol_table* symtab, Layout* layout)
709 if (this->got_ == NULL)
711 gold_assert(symtab != NULL && layout != NULL);
713 this->got_ = new Output_data_got<32, false>();
715 // When using -z now, we can treat .got.plt as a relro section.
716 // Without -z now, it is modified after program startup by lazy
718 bool is_got_plt_relro = parameters->options().now();
719 Output_section_order got_order = (is_got_plt_relro
722 Output_section_order got_plt_order = (is_got_plt_relro
724 : ORDER_NON_RELRO_FIRST);
726 layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
728 | elfcpp::SHF_WRITE),
729 this->got_, got_order, true);
731 this->got_plt_ = new Output_data_space(4, "** GOT PLT");
732 layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
734 | elfcpp::SHF_WRITE),
735 this->got_plt_, got_plt_order,
738 // The first three entries are reserved.
739 this->got_plt_->set_current_data_size(3 * 4);
741 if (!is_got_plt_relro)
743 // Those bytes can go into the relro segment.
744 layout->increase_relro(3 * 4);
747 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
748 this->global_offset_table_ =
749 symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
750 Symbol_table::PREDEFINED,
752 0, 0, elfcpp::STT_OBJECT,
754 elfcpp::STV_HIDDEN, 0,
757 // If there are any IRELATIVE relocations, they get GOT entries
758 // in .got.plt after the jump slot relocations.
759 this->got_irelative_ = new Output_data_space(4, "** GOT IRELATIVE PLT");
760 layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
762 | elfcpp::SHF_WRITE),
763 this->got_irelative_,
764 got_plt_order, is_got_plt_relro);
766 // If there are any TLSDESC relocations, they get GOT entries in
767 // .got.plt after the jump slot entries.
768 this->got_tlsdesc_ = new Output_data_got<32, false>();
769 layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
771 | elfcpp::SHF_WRITE),
773 got_plt_order, is_got_plt_relro);
779 // Get the dynamic reloc section, creating it if necessary.
781 Target_i386::Reloc_section*
782 Target_i386::rel_dyn_section(Layout* layout)
784 if (this->rel_dyn_ == NULL)
786 gold_assert(layout != NULL);
787 this->rel_dyn_ = new Reloc_section(parameters->options().combreloc());
788 layout->add_output_section_data(".rel.dyn", elfcpp::SHT_REL,
789 elfcpp::SHF_ALLOC, this->rel_dyn_,
790 ORDER_DYNAMIC_RELOCS, false);
792 return this->rel_dyn_;
795 // Get the section to use for IRELATIVE relocs, creating it if
796 // necessary. These go in .rel.dyn, but only after all other dynamic
797 // relocations. They need to follow the other dynamic relocations so
798 // that they can refer to global variables initialized by those
801 Target_i386::Reloc_section*
802 Target_i386::rel_irelative_section(Layout* layout)
804 if (this->rel_irelative_ == NULL)
806 // Make sure we have already create the dynamic reloc section.
807 this->rel_dyn_section(layout);
808 this->rel_irelative_ = new Reloc_section(false);
809 layout->add_output_section_data(".rel.dyn", elfcpp::SHT_REL,
810 elfcpp::SHF_ALLOC, this->rel_irelative_,
811 ORDER_DYNAMIC_RELOCS, false);
812 gold_assert(this->rel_dyn_->output_section()
813 == this->rel_irelative_->output_section());
815 return this->rel_irelative_;
818 // Create the PLT section. The ordinary .got section is an argument,
819 // since we need to refer to the start. We also create our own .got
820 // section just for PLT entries.
822 Output_data_plt_i386::Output_data_plt_i386(Layout* layout,
823 Output_data_space* got_plt,
824 Output_data_space* got_irelative)
825 : Output_section_data(16), tls_desc_rel_(NULL), irelative_rel_(NULL),
826 got_plt_(got_plt), got_irelative_(got_irelative), count_(0),
827 irelative_count_(0), global_ifuncs_(), local_ifuncs_()
829 this->rel_ = new Reloc_section(false);
830 layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL,
831 elfcpp::SHF_ALLOC, this->rel_,
832 ORDER_DYNAMIC_PLT_RELOCS, false);
834 // Add unwind information if requested.
835 if (parameters->options().ld_generated_unwind_info())
836 layout->add_eh_frame_for_plt(this, plt_eh_frame_cie, plt_eh_frame_cie_size,
837 plt_eh_frame_fde, plt_eh_frame_fde_size);
841 Output_data_plt_i386::do_adjust_output_section(Output_section* os)
843 // UnixWare sets the entsize of .plt to 4, and so does the old GNU
844 // linker, and so do we.
848 // Add an entry to the PLT.
851 Output_data_plt_i386::add_entry(Symbol_table* symtab, Layout* layout,
854 gold_assert(!gsym->has_plt_offset());
856 // Every PLT entry needs a reloc.
857 if (gsym->type() == elfcpp::STT_GNU_IFUNC
858 && gsym->can_use_relative_reloc(false))
860 gsym->set_plt_offset(this->irelative_count_ * plt_entry_size);
861 ++this->irelative_count_;
862 section_offset_type got_offset =
863 this->got_irelative_->current_data_size();
864 this->got_irelative_->set_current_data_size(got_offset + 4);
865 Reloc_section* rel = this->rel_irelative(symtab, layout);
866 rel->add_symbolless_global_addend(gsym, elfcpp::R_386_IRELATIVE,
867 this->got_irelative_, got_offset);
868 struct Global_ifunc gi;
870 gi.got_offset = got_offset;
871 this->global_ifuncs_.push_back(gi);
875 // When setting the PLT offset we skip the initial reserved PLT
877 gsym->set_plt_offset((this->count_ + 1) * plt_entry_size);
881 section_offset_type got_offset = this->got_plt_->current_data_size();
883 // Every PLT entry needs a GOT entry which points back to the
884 // PLT entry (this will be changed by the dynamic linker,
885 // normally lazily when the function is called).
886 this->got_plt_->set_current_data_size(got_offset + 4);
888 gsym->set_needs_dynsym_entry();
889 this->rel_->add_global(gsym, elfcpp::R_386_JUMP_SLOT, this->got_plt_,
893 // Note that we don't need to save the symbol. The contents of the
894 // PLT are independent of which symbols are used. The symbols only
895 // appear in the relocations.
898 // Add an entry to the PLT for a local STT_GNU_IFUNC symbol. Return
902 Output_data_plt_i386::add_local_ifunc_entry(
903 Symbol_table* symtab,
905 Sized_relobj_file<32, false>* relobj,
906 unsigned int local_sym_index)
908 unsigned int plt_offset = this->irelative_count_ * plt_entry_size;
909 ++this->irelative_count_;
911 section_offset_type got_offset = this->got_irelative_->current_data_size();
913 // Every PLT entry needs a GOT entry which points back to the PLT
915 this->got_irelative_->set_current_data_size(got_offset + 4);
917 // Every PLT entry needs a reloc.
918 Reloc_section* rel = this->rel_irelative(symtab, layout);
919 rel->add_symbolless_local_addend(relobj, local_sym_index,
920 elfcpp::R_386_IRELATIVE,
921 this->got_irelative_, got_offset);
923 struct Local_ifunc li;
925 li.local_sym_index = local_sym_index;
926 li.got_offset = got_offset;
927 this->local_ifuncs_.push_back(li);
932 // Return where the TLS_DESC relocations should go, creating it if
933 // necessary. These follow the JUMP_SLOT relocations.
935 Output_data_plt_i386::Reloc_section*
936 Output_data_plt_i386::rel_tls_desc(Layout* layout)
938 if (this->tls_desc_rel_ == NULL)
940 this->tls_desc_rel_ = new Reloc_section(false);
941 layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL,
942 elfcpp::SHF_ALLOC, this->tls_desc_rel_,
943 ORDER_DYNAMIC_PLT_RELOCS, false);
944 gold_assert(this->tls_desc_rel_->output_section()
945 == this->rel_->output_section());
947 return this->tls_desc_rel_;
950 // Return where the IRELATIVE relocations should go in the PLT. These
951 // follow the JUMP_SLOT and TLS_DESC relocations.
953 Output_data_plt_i386::Reloc_section*
954 Output_data_plt_i386::rel_irelative(Symbol_table* symtab, Layout* layout)
956 if (this->irelative_rel_ == NULL)
958 // Make sure we have a place for the TLS_DESC relocations, in
959 // case we see any later on.
960 this->rel_tls_desc(layout);
961 this->irelative_rel_ = new Reloc_section(false);
962 layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL,
963 elfcpp::SHF_ALLOC, this->irelative_rel_,
964 ORDER_DYNAMIC_PLT_RELOCS, false);
965 gold_assert(this->irelative_rel_->output_section()
966 == this->rel_->output_section());
968 if (parameters->doing_static_link())
970 // A statically linked executable will only have a .rel.plt
971 // section to hold R_386_IRELATIVE relocs for STT_GNU_IFUNC
972 // symbols. The library will use these symbols to locate
973 // the IRELATIVE relocs at program startup time.
974 symtab->define_in_output_data("__rel_iplt_start", NULL,
975 Symbol_table::PREDEFINED,
976 this->irelative_rel_, 0, 0,
977 elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL,
978 elfcpp::STV_HIDDEN, 0, false, true);
979 symtab->define_in_output_data("__rel_iplt_end", NULL,
980 Symbol_table::PREDEFINED,
981 this->irelative_rel_, 0, 0,
982 elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL,
983 elfcpp::STV_HIDDEN, 0, true, true);
986 return this->irelative_rel_;
989 // Return the PLT address to use for a global symbol.
992 Output_data_plt_i386::address_for_global(const Symbol* gsym)
995 if (gsym->type() == elfcpp::STT_GNU_IFUNC
996 && gsym->can_use_relative_reloc(false))
997 offset = (this->count_ + 1) * plt_entry_size;
998 return this->address() + offset;
1001 // Return the PLT address to use for a local symbol. These are always
1002 // IRELATIVE relocs.
1005 Output_data_plt_i386::address_for_local(const Relobj*, unsigned int)
1007 return this->address() + (this->count_ + 1) * plt_entry_size;
1010 // The first entry in the PLT for an executable.
1012 const unsigned char Output_data_plt_i386::exec_first_plt_entry[plt_entry_size] =
1014 0xff, 0x35, // pushl contents of memory address
1015 0, 0, 0, 0, // replaced with address of .got + 4
1016 0xff, 0x25, // jmp indirect
1017 0, 0, 0, 0, // replaced with address of .got + 8
1018 0, 0, 0, 0 // unused
1021 // The first entry in the PLT for a shared object.
1023 const unsigned char Output_data_plt_i386::dyn_first_plt_entry[plt_entry_size] =
1025 0xff, 0xb3, 4, 0, 0, 0, // pushl 4(%ebx)
1026 0xff, 0xa3, 8, 0, 0, 0, // jmp *8(%ebx)
1027 0, 0, 0, 0 // unused
1030 // Subsequent entries in the PLT for an executable.
1032 const unsigned char Output_data_plt_i386::exec_plt_entry[plt_entry_size] =
1034 0xff, 0x25, // jmp indirect
1035 0, 0, 0, 0, // replaced with address of symbol in .got
1036 0x68, // pushl immediate
1037 0, 0, 0, 0, // replaced with offset into relocation table
1038 0xe9, // jmp relative
1039 0, 0, 0, 0 // replaced with offset to start of .plt
1042 // Subsequent entries in the PLT for a shared object.
1044 const unsigned char Output_data_plt_i386::dyn_plt_entry[plt_entry_size] =
1046 0xff, 0xa3, // jmp *offset(%ebx)
1047 0, 0, 0, 0, // replaced with offset of symbol in .got
1048 0x68, // pushl immediate
1049 0, 0, 0, 0, // replaced with offset into relocation table
1050 0xe9, // jmp relative
1051 0, 0, 0, 0 // replaced with offset to start of .plt
1054 // The .eh_frame unwind information for the PLT.
1057 Output_data_plt_i386::plt_eh_frame_cie[plt_eh_frame_cie_size] =
1060 'z', // Augmentation: augmentation size included.
1061 'R', // Augmentation: FDE encoding included.
1062 '\0', // End of augmentation string.
1063 1, // Code alignment factor.
1064 0x7c, // Data alignment factor.
1065 8, // Return address column.
1066 1, // Augmentation size.
1067 (elfcpp::DW_EH_PE_pcrel // FDE encoding.
1068 | elfcpp::DW_EH_PE_sdata4),
1069 elfcpp::DW_CFA_def_cfa, 4, 4, // DW_CFA_def_cfa: r4 (esp) ofs 4.
1070 elfcpp::DW_CFA_offset + 8, 1, // DW_CFA_offset: r8 (eip) at cfa-4.
1071 elfcpp::DW_CFA_nop, // Align to 16 bytes.
1076 Output_data_plt_i386::plt_eh_frame_fde[plt_eh_frame_fde_size] =
1078 0, 0, 0, 0, // Replaced with offset to .plt.
1079 0, 0, 0, 0, // Replaced with size of .plt.
1080 0, // Augmentation size.
1081 elfcpp::DW_CFA_def_cfa_offset, 8, // DW_CFA_def_cfa_offset: 8.
1082 elfcpp::DW_CFA_advance_loc + 6, // Advance 6 to __PLT__ + 6.
1083 elfcpp::DW_CFA_def_cfa_offset, 12, // DW_CFA_def_cfa_offset: 12.
1084 elfcpp::DW_CFA_advance_loc + 10, // Advance 10 to __PLT__ + 16.
1085 elfcpp::DW_CFA_def_cfa_expression, // DW_CFA_def_cfa_expression.
1086 11, // Block length.
1087 elfcpp::DW_OP_breg4, 4, // Push %esp + 4.
1088 elfcpp::DW_OP_breg8, 0, // Push %eip.
1089 elfcpp::DW_OP_lit15, // Push 0xf.
1090 elfcpp::DW_OP_and, // & (%eip & 0xf).
1091 elfcpp::DW_OP_lit11, // Push 0xb.
1092 elfcpp::DW_OP_ge, // >= ((%eip & 0xf) >= 0xb)
1093 elfcpp::DW_OP_lit2, // Push 2.
1094 elfcpp::DW_OP_shl, // << (((%eip & 0xf) >= 0xb) << 2)
1095 elfcpp::DW_OP_plus, // + ((((%eip&0xf)>=0xb)<<2)+%esp+4
1096 elfcpp::DW_CFA_nop, // Align to 32 bytes.
1102 // Write out the PLT. This uses the hand-coded instructions above,
1103 // and adjusts them as needed. This is all specified by the i386 ELF
1104 // Processor Supplement.
1107 Output_data_plt_i386::do_write(Output_file* of)
1109 const off_t offset = this->offset();
1110 const section_size_type oview_size =
1111 convert_to_section_size_type(this->data_size());
1112 unsigned char* const oview = of->get_output_view(offset, oview_size);
1114 const off_t got_file_offset = this->got_plt_->offset();
1115 gold_assert(parameters->incremental_update()
1116 || (got_file_offset + this->got_plt_->data_size()
1117 == this->got_irelative_->offset()));
1118 const section_size_type got_size =
1119 convert_to_section_size_type(this->got_plt_->data_size()
1120 + this->got_irelative_->data_size());
1121 unsigned char* const got_view = of->get_output_view(got_file_offset,
1124 unsigned char* pov = oview;
1126 elfcpp::Elf_types<32>::Elf_Addr plt_address = this->address();
1127 elfcpp::Elf_types<32>::Elf_Addr got_address = this->got_plt_->address();
1129 if (parameters->options().output_is_position_independent())
1130 memcpy(pov, dyn_first_plt_entry, plt_entry_size);
1133 memcpy(pov, exec_first_plt_entry, plt_entry_size);
1134 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_address + 4);
1135 elfcpp::Swap<32, false>::writeval(pov + 8, got_address + 8);
1137 pov += plt_entry_size;
1139 unsigned char* got_pov = got_view;
1141 memset(got_pov, 0, 12);
1144 const int rel_size = elfcpp::Elf_sizes<32>::rel_size;
1146 unsigned int plt_offset = plt_entry_size;
1147 unsigned int plt_rel_offset = 0;
1148 unsigned int got_offset = 12;
1149 const unsigned int count = this->count_ + this->irelative_count_;
1150 for (unsigned int i = 0;
1153 pov += plt_entry_size,
1155 plt_offset += plt_entry_size,
1156 plt_rel_offset += rel_size,
1159 // Set and adjust the PLT entry itself.
1161 if (parameters->options().output_is_position_independent())
1163 memcpy(pov, dyn_plt_entry, plt_entry_size);
1164 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2, got_offset);
1168 memcpy(pov, exec_plt_entry, plt_entry_size);
1169 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
1174 elfcpp::Swap_unaligned<32, false>::writeval(pov + 7, plt_rel_offset);
1175 elfcpp::Swap<32, false>::writeval(pov + 12,
1176 - (plt_offset + plt_entry_size));
1178 // Set the entry in the GOT.
1179 elfcpp::Swap<32, false>::writeval(got_pov, plt_address + plt_offset + 6);
1182 // If any STT_GNU_IFUNC symbols have PLT entries, we need to change
1183 // the GOT to point to the actual symbol value, rather than point to
1184 // the PLT entry. That will let the dynamic linker call the right
1185 // function when resolving IRELATIVE relocations.
1186 unsigned char* got_irelative_view = got_view + this->got_plt_->data_size();
1187 for (std::vector<Global_ifunc>::const_iterator p =
1188 this->global_ifuncs_.begin();
1189 p != this->global_ifuncs_.end();
1192 const Sized_symbol<32>* ssym =
1193 static_cast<const Sized_symbol<32>*>(p->sym);
1194 elfcpp::Swap<32, false>::writeval(got_irelative_view + p->got_offset,
1198 for (std::vector<Local_ifunc>::const_iterator p =
1199 this->local_ifuncs_.begin();
1200 p != this->local_ifuncs_.end();
1203 const Symbol_value<32>* psymval =
1204 p->object->local_symbol(p->local_sym_index);
1205 elfcpp::Swap<32, false>::writeval(got_irelative_view + p->got_offset,
1206 psymval->value(p->object, 0));
1209 gold_assert(static_cast<section_size_type>(pov - oview) == oview_size);
1210 gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size);
1212 of->write_output_view(offset, oview_size, oview);
1213 of->write_output_view(got_file_offset, got_size, got_view);
1216 // Create the PLT section.
1219 Target_i386::make_plt_section(Symbol_table* symtab, Layout* layout)
1221 if (this->plt_ == NULL)
1223 // Create the GOT sections first.
1224 this->got_section(symtab, layout);
1226 this->plt_ = new Output_data_plt_i386(layout, this->got_plt_,
1227 this->got_irelative_);
1228 layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
1230 | elfcpp::SHF_EXECINSTR),
1231 this->plt_, ORDER_PLT, false);
1233 // Make the sh_info field of .rel.plt point to .plt.
1234 Output_section* rel_plt_os = this->plt_->rel_plt()->output_section();
1235 rel_plt_os->set_info_section(this->plt_->output_section());
1239 // Create a PLT entry for a global symbol.
1242 Target_i386::make_plt_entry(Symbol_table* symtab, Layout* layout, Symbol* gsym)
1244 if (gsym->has_plt_offset())
1246 if (this->plt_ == NULL)
1247 this->make_plt_section(symtab, layout);
1248 this->plt_->add_entry(symtab, layout, gsym);
1251 // Make a PLT entry for a local STT_GNU_IFUNC symbol.
1254 Target_i386::make_local_ifunc_plt_entry(Symbol_table* symtab, Layout* layout,
1255 Sized_relobj_file<32, false>* relobj,
1256 unsigned int local_sym_index)
1258 if (relobj->local_has_plt_offset(local_sym_index))
1260 if (this->plt_ == NULL)
1261 this->make_plt_section(symtab, layout);
1262 unsigned int plt_offset = this->plt_->add_local_ifunc_entry(symtab, layout,
1265 relobj->set_local_plt_offset(local_sym_index, plt_offset);
1268 // Return the number of entries in the PLT.
1271 Target_i386::plt_entry_count() const
1273 if (this->plt_ == NULL)
1275 return this->plt_->entry_count();
1278 // Return the offset of the first non-reserved PLT entry.
1281 Target_i386::first_plt_entry_offset() const
1283 return Output_data_plt_i386::first_plt_entry_offset();
1286 // Return the size of each PLT entry.
1289 Target_i386::plt_entry_size() const
1291 return Output_data_plt_i386::get_plt_entry_size();
1294 // Get the section to use for TLS_DESC relocations.
1296 Target_i386::Reloc_section*
1297 Target_i386::rel_tls_desc_section(Layout* layout) const
1299 return this->plt_section()->rel_tls_desc(layout);
1302 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
1305 Target_i386::define_tls_base_symbol(Symbol_table* symtab, Layout* layout)
1307 if (this->tls_base_symbol_defined_)
1310 Output_segment* tls_segment = layout->tls_segment();
1311 if (tls_segment != NULL)
1313 bool is_exec = parameters->options().output_is_executable();
1314 symtab->define_in_output_segment("_TLS_MODULE_BASE_", NULL,
1315 Symbol_table::PREDEFINED,
1319 elfcpp::STV_HIDDEN, 0,
1321 ? Symbol::SEGMENT_END
1322 : Symbol::SEGMENT_START),
1325 this->tls_base_symbol_defined_ = true;
1328 // Create a GOT entry for the TLS module index.
1331 Target_i386::got_mod_index_entry(Symbol_table* symtab, Layout* layout,
1332 Sized_relobj_file<32, false>* object)
1334 if (this->got_mod_index_offset_ == -1U)
1336 gold_assert(symtab != NULL && layout != NULL && object != NULL);
1337 Reloc_section* rel_dyn = this->rel_dyn_section(layout);
1338 Output_data_got<32, false>* got = this->got_section(symtab, layout);
1339 unsigned int got_offset = got->add_constant(0);
1340 rel_dyn->add_local(object, 0, elfcpp::R_386_TLS_DTPMOD32, got,
1342 got->add_constant(0);
1343 this->got_mod_index_offset_ = got_offset;
1345 return this->got_mod_index_offset_;
1348 // Optimize the TLS relocation type based on what we know about the
1349 // symbol. IS_FINAL is true if the final address of this symbol is
1350 // known at link time.
1352 tls::Tls_optimization
1353 Target_i386::optimize_tls_reloc(bool is_final, int r_type)
1355 // If we are generating a shared library, then we can't do anything
1357 if (parameters->options().shared())
1358 return tls::TLSOPT_NONE;
1362 case elfcpp::R_386_TLS_GD:
1363 case elfcpp::R_386_TLS_GOTDESC:
1364 case elfcpp::R_386_TLS_DESC_CALL:
1365 // These are General-Dynamic which permits fully general TLS
1366 // access. Since we know that we are generating an executable,
1367 // we can convert this to Initial-Exec. If we also know that
1368 // this is a local symbol, we can further switch to Local-Exec.
1370 return tls::TLSOPT_TO_LE;
1371 return tls::TLSOPT_TO_IE;
1373 case elfcpp::R_386_TLS_LDM:
1374 // This is Local-Dynamic, which refers to a local symbol in the
1375 // dynamic TLS block. Since we know that we generating an
1376 // executable, we can switch to Local-Exec.
1377 return tls::TLSOPT_TO_LE;
1379 case elfcpp::R_386_TLS_LDO_32:
1380 // Another type of Local-Dynamic relocation.
1381 return tls::TLSOPT_TO_LE;
1383 case elfcpp::R_386_TLS_IE:
1384 case elfcpp::R_386_TLS_GOTIE:
1385 case elfcpp::R_386_TLS_IE_32:
1386 // These are Initial-Exec relocs which get the thread offset
1387 // from the GOT. If we know that we are linking against the
1388 // local symbol, we can switch to Local-Exec, which links the
1389 // thread offset into the instruction.
1391 return tls::TLSOPT_TO_LE;
1392 return tls::TLSOPT_NONE;
1394 case elfcpp::R_386_TLS_LE:
1395 case elfcpp::R_386_TLS_LE_32:
1396 // When we already have Local-Exec, there is nothing further we
1398 return tls::TLSOPT_NONE;
1405 // Get the Reference_flags for a particular relocation.
1408 Target_i386::Scan::get_reference_flags(unsigned int r_type)
1412 case elfcpp::R_386_NONE:
1413 case elfcpp::R_386_GNU_VTINHERIT:
1414 case elfcpp::R_386_GNU_VTENTRY:
1415 case elfcpp::R_386_GOTPC:
1416 // No symbol reference.
1419 case elfcpp::R_386_32:
1420 case elfcpp::R_386_16:
1421 case elfcpp::R_386_8:
1422 return Symbol::ABSOLUTE_REF;
1424 case elfcpp::R_386_PC32:
1425 case elfcpp::R_386_PC16:
1426 case elfcpp::R_386_PC8:
1427 case elfcpp::R_386_GOTOFF:
1428 return Symbol::RELATIVE_REF;
1430 case elfcpp::R_386_PLT32:
1431 return Symbol::FUNCTION_CALL | Symbol::RELATIVE_REF;
1433 case elfcpp::R_386_GOT32:
1435 return Symbol::ABSOLUTE_REF;
1437 case elfcpp::R_386_TLS_GD: // Global-dynamic
1438 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url)
1439 case elfcpp::R_386_TLS_DESC_CALL:
1440 case elfcpp::R_386_TLS_LDM: // Local-dynamic
1441 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
1442 case elfcpp::R_386_TLS_IE: // Initial-exec
1443 case elfcpp::R_386_TLS_IE_32:
1444 case elfcpp::R_386_TLS_GOTIE:
1445 case elfcpp::R_386_TLS_LE: // Local-exec
1446 case elfcpp::R_386_TLS_LE_32:
1447 return Symbol::TLS_REF;
1449 case elfcpp::R_386_COPY:
1450 case elfcpp::R_386_GLOB_DAT:
1451 case elfcpp::R_386_JUMP_SLOT:
1452 case elfcpp::R_386_RELATIVE:
1453 case elfcpp::R_386_IRELATIVE:
1454 case elfcpp::R_386_TLS_TPOFF:
1455 case elfcpp::R_386_TLS_DTPMOD32:
1456 case elfcpp::R_386_TLS_DTPOFF32:
1457 case elfcpp::R_386_TLS_TPOFF32:
1458 case elfcpp::R_386_TLS_DESC:
1459 case elfcpp::R_386_32PLT:
1460 case elfcpp::R_386_TLS_GD_32:
1461 case elfcpp::R_386_TLS_GD_PUSH:
1462 case elfcpp::R_386_TLS_GD_CALL:
1463 case elfcpp::R_386_TLS_GD_POP:
1464 case elfcpp::R_386_TLS_LDM_32:
1465 case elfcpp::R_386_TLS_LDM_PUSH:
1466 case elfcpp::R_386_TLS_LDM_CALL:
1467 case elfcpp::R_386_TLS_LDM_POP:
1468 case elfcpp::R_386_USED_BY_INTEL_200:
1470 // Not expected. We will give an error later.
1475 // Report an unsupported relocation against a local symbol.
1478 Target_i386::Scan::unsupported_reloc_local(Sized_relobj_file<32, false>* object,
1479 unsigned int r_type)
1481 gold_error(_("%s: unsupported reloc %u against local symbol"),
1482 object->name().c_str(), r_type);
1485 // Return whether we need to make a PLT entry for a relocation of a
1486 // given type against a STT_GNU_IFUNC symbol.
1489 Target_i386::Scan::reloc_needs_plt_for_ifunc(
1490 Sized_relobj_file<32, false>* object,
1491 unsigned int r_type)
1493 int flags = Scan::get_reference_flags(r_type);
1494 if (flags & Symbol::TLS_REF)
1495 gold_error(_("%s: unsupported TLS reloc %u for IFUNC symbol"),
1496 object->name().c_str(), r_type);
1500 // Scan a relocation for a local symbol.
1503 Target_i386::Scan::local(Symbol_table* symtab,
1505 Target_i386* target,
1506 Sized_relobj_file<32, false>* object,
1507 unsigned int data_shndx,
1508 Output_section* output_section,
1509 const elfcpp::Rel<32, false>& reloc,
1510 unsigned int r_type,
1511 const elfcpp::Sym<32, false>& lsym)
1513 // A local STT_GNU_IFUNC symbol may require a PLT entry.
1514 if (lsym.get_st_type() == elfcpp::STT_GNU_IFUNC
1515 && this->reloc_needs_plt_for_ifunc(object, r_type))
1517 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1518 target->make_local_ifunc_plt_entry(symtab, layout, object, r_sym);
1523 case elfcpp::R_386_NONE:
1524 case elfcpp::R_386_GNU_VTINHERIT:
1525 case elfcpp::R_386_GNU_VTENTRY:
1528 case elfcpp::R_386_32:
1529 // If building a shared library (or a position-independent
1530 // executable), we need to create a dynamic relocation for
1531 // this location. The relocation applied at link time will
1532 // apply the link-time value, so we flag the location with
1533 // an R_386_RELATIVE relocation so the dynamic loader can
1534 // relocate it easily.
1535 if (parameters->options().output_is_position_independent())
1537 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1538 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1539 rel_dyn->add_local_relative(object, r_sym, elfcpp::R_386_RELATIVE,
1540 output_section, data_shndx,
1541 reloc.get_r_offset());
1545 case elfcpp::R_386_16:
1546 case elfcpp::R_386_8:
1547 // If building a shared library (or a position-independent
1548 // executable), we need to create a dynamic relocation for
1549 // this location. Because the addend needs to remain in the
1550 // data section, we need to be careful not to apply this
1551 // relocation statically.
1552 if (parameters->options().output_is_position_independent())
1554 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1555 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1556 if (lsym.get_st_type() != elfcpp::STT_SECTION)
1557 rel_dyn->add_local(object, r_sym, r_type, output_section,
1558 data_shndx, reloc.get_r_offset());
1561 gold_assert(lsym.get_st_value() == 0);
1562 unsigned int shndx = lsym.get_st_shndx();
1564 shndx = object->adjust_sym_shndx(r_sym, shndx,
1567 object->error(_("section symbol %u has bad shndx %u"),
1570 rel_dyn->add_local_section(object, shndx,
1571 r_type, output_section,
1572 data_shndx, reloc.get_r_offset());
1577 case elfcpp::R_386_PC32:
1578 case elfcpp::R_386_PC16:
1579 case elfcpp::R_386_PC8:
1582 case elfcpp::R_386_PLT32:
1583 // Since we know this is a local symbol, we can handle this as a
1587 case elfcpp::R_386_GOTOFF:
1588 case elfcpp::R_386_GOTPC:
1589 // We need a GOT section.
1590 target->got_section(symtab, layout);
1593 case elfcpp::R_386_GOT32:
1595 // The symbol requires a GOT entry.
1596 Output_data_got<32, false>* got = target->got_section(symtab, layout);
1597 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1599 // For a STT_GNU_IFUNC symbol we want the PLT offset. That
1600 // lets function pointers compare correctly with shared
1601 // libraries. Otherwise we would need an IRELATIVE reloc.
1603 if (lsym.get_st_type() == elfcpp::STT_GNU_IFUNC)
1604 is_new = got->add_local_plt(object, r_sym, GOT_TYPE_STANDARD);
1606 is_new = got->add_local(object, r_sym, GOT_TYPE_STANDARD);
1609 // If we are generating a shared object, we need to add a
1610 // dynamic RELATIVE relocation for this symbol's GOT entry.
1611 if (parameters->options().output_is_position_independent())
1613 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1614 unsigned int got_offset =
1615 object->local_got_offset(r_sym, GOT_TYPE_STANDARD);
1616 rel_dyn->add_local_relative(object, r_sym,
1617 elfcpp::R_386_RELATIVE,
1624 // These are relocations which should only be seen by the
1625 // dynamic linker, and should never be seen here.
1626 case elfcpp::R_386_COPY:
1627 case elfcpp::R_386_GLOB_DAT:
1628 case elfcpp::R_386_JUMP_SLOT:
1629 case elfcpp::R_386_RELATIVE:
1630 case elfcpp::R_386_IRELATIVE:
1631 case elfcpp::R_386_TLS_TPOFF:
1632 case elfcpp::R_386_TLS_DTPMOD32:
1633 case elfcpp::R_386_TLS_DTPOFF32:
1634 case elfcpp::R_386_TLS_TPOFF32:
1635 case elfcpp::R_386_TLS_DESC:
1636 gold_error(_("%s: unexpected reloc %u in object file"),
1637 object->name().c_str(), r_type);
1640 // These are initial TLS relocs, which are expected when
1642 case elfcpp::R_386_TLS_GD: // Global-dynamic
1643 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url)
1644 case elfcpp::R_386_TLS_DESC_CALL:
1645 case elfcpp::R_386_TLS_LDM: // Local-dynamic
1646 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
1647 case elfcpp::R_386_TLS_IE: // Initial-exec
1648 case elfcpp::R_386_TLS_IE_32:
1649 case elfcpp::R_386_TLS_GOTIE:
1650 case elfcpp::R_386_TLS_LE: // Local-exec
1651 case elfcpp::R_386_TLS_LE_32:
1653 bool output_is_shared = parameters->options().shared();
1654 const tls::Tls_optimization optimized_type
1655 = Target_i386::optimize_tls_reloc(!output_is_shared, r_type);
1658 case elfcpp::R_386_TLS_GD: // Global-dynamic
1659 if (optimized_type == tls::TLSOPT_NONE)
1661 // Create a pair of GOT entries for the module index and
1662 // dtv-relative offset.
1663 Output_data_got<32, false>* got
1664 = target->got_section(symtab, layout);
1665 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1666 unsigned int shndx = lsym.get_st_shndx();
1668 shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
1670 object->error(_("local symbol %u has bad shndx %u"),
1673 got->add_local_pair_with_rel(object, r_sym, shndx,
1675 target->rel_dyn_section(layout),
1676 elfcpp::R_386_TLS_DTPMOD32, 0);
1678 else if (optimized_type != tls::TLSOPT_TO_LE)
1679 unsupported_reloc_local(object, r_type);
1682 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva)
1683 target->define_tls_base_symbol(symtab, layout);
1684 if (optimized_type == tls::TLSOPT_NONE)
1686 // Create a double GOT entry with an R_386_TLS_DESC
1687 // reloc. The R_386_TLS_DESC reloc is resolved
1688 // lazily, so the GOT entry needs to be in an area in
1689 // .got.plt, not .got. Call got_section to make sure
1690 // the section has been created.
1691 target->got_section(symtab, layout);
1692 Output_data_got<32, false>* got = target->got_tlsdesc_section();
1693 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1694 if (!object->local_has_got_offset(r_sym, GOT_TYPE_TLS_DESC))
1696 unsigned int got_offset = got->add_constant(0);
1697 // The local symbol value is stored in the second
1699 got->add_local(object, r_sym, GOT_TYPE_TLS_DESC);
1700 // That set the GOT offset of the local symbol to
1701 // point to the second entry, but we want it to
1702 // point to the first.
1703 object->set_local_got_offset(r_sym, GOT_TYPE_TLS_DESC,
1705 Reloc_section* rt = target->rel_tls_desc_section(layout);
1706 rt->add_absolute(elfcpp::R_386_TLS_DESC, got, got_offset);
1709 else if (optimized_type != tls::TLSOPT_TO_LE)
1710 unsupported_reloc_local(object, r_type);
1713 case elfcpp::R_386_TLS_DESC_CALL:
1716 case elfcpp::R_386_TLS_LDM: // Local-dynamic
1717 if (optimized_type == tls::TLSOPT_NONE)
1719 // Create a GOT entry for the module index.
1720 target->got_mod_index_entry(symtab, layout, object);
1722 else if (optimized_type != tls::TLSOPT_TO_LE)
1723 unsupported_reloc_local(object, r_type);
1726 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
1729 case elfcpp::R_386_TLS_IE: // Initial-exec
1730 case elfcpp::R_386_TLS_IE_32:
1731 case elfcpp::R_386_TLS_GOTIE:
1732 layout->set_has_static_tls();
1733 if (optimized_type == tls::TLSOPT_NONE)
1735 // For the R_386_TLS_IE relocation, we need to create a
1736 // dynamic relocation when building a shared library.
1737 if (r_type == elfcpp::R_386_TLS_IE
1738 && parameters->options().shared())
1740 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1742 = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1743 rel_dyn->add_local_relative(object, r_sym,
1744 elfcpp::R_386_RELATIVE,
1745 output_section, data_shndx,
1746 reloc.get_r_offset());
1748 // Create a GOT entry for the tp-relative offset.
1749 Output_data_got<32, false>* got
1750 = target->got_section(symtab, layout);
1751 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1752 unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_IE_32
1753 ? elfcpp::R_386_TLS_TPOFF32
1754 : elfcpp::R_386_TLS_TPOFF);
1755 unsigned int got_type = (r_type == elfcpp::R_386_TLS_IE_32
1756 ? GOT_TYPE_TLS_OFFSET
1757 : GOT_TYPE_TLS_NOFFSET);
1758 got->add_local_with_rel(object, r_sym, got_type,
1759 target->rel_dyn_section(layout),
1762 else if (optimized_type != tls::TLSOPT_TO_LE)
1763 unsupported_reloc_local(object, r_type);
1766 case elfcpp::R_386_TLS_LE: // Local-exec
1767 case elfcpp::R_386_TLS_LE_32:
1768 layout->set_has_static_tls();
1769 if (output_is_shared)
1771 // We need to create a dynamic relocation.
1772 gold_assert(lsym.get_st_type() != elfcpp::STT_SECTION);
1773 unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
1774 unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_LE_32
1775 ? elfcpp::R_386_TLS_TPOFF32
1776 : elfcpp::R_386_TLS_TPOFF);
1777 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1778 rel_dyn->add_local(object, r_sym, dyn_r_type, output_section,
1779 data_shndx, reloc.get_r_offset());
1789 case elfcpp::R_386_32PLT:
1790 case elfcpp::R_386_TLS_GD_32:
1791 case elfcpp::R_386_TLS_GD_PUSH:
1792 case elfcpp::R_386_TLS_GD_CALL:
1793 case elfcpp::R_386_TLS_GD_POP:
1794 case elfcpp::R_386_TLS_LDM_32:
1795 case elfcpp::R_386_TLS_LDM_PUSH:
1796 case elfcpp::R_386_TLS_LDM_CALL:
1797 case elfcpp::R_386_TLS_LDM_POP:
1798 case elfcpp::R_386_USED_BY_INTEL_200:
1800 unsupported_reloc_local(object, r_type);
1805 // Report an unsupported relocation against a global symbol.
1808 Target_i386::Scan::unsupported_reloc_global(
1809 Sized_relobj_file<32, false>* object,
1810 unsigned int r_type,
1813 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
1814 object->name().c_str(), r_type, gsym->demangled_name().c_str());
1818 Target_i386::Scan::possible_function_pointer_reloc(unsigned int r_type)
1822 case elfcpp::R_386_32:
1823 case elfcpp::R_386_16:
1824 case elfcpp::R_386_8:
1825 case elfcpp::R_386_GOTOFF:
1826 case elfcpp::R_386_GOT32:
1837 Target_i386::Scan::local_reloc_may_be_function_pointer(
1841 Sized_relobj_file<32, false>* ,
1844 const elfcpp::Rel<32, false>& ,
1845 unsigned int r_type,
1846 const elfcpp::Sym<32, false>&)
1848 return possible_function_pointer_reloc(r_type);
1852 Target_i386::Scan::global_reloc_may_be_function_pointer(
1856 Sized_relobj_file<32, false>* ,
1859 const elfcpp::Rel<32, false>& ,
1860 unsigned int r_type,
1863 return possible_function_pointer_reloc(r_type);
1866 // Scan a relocation for a global symbol.
1869 Target_i386::Scan::global(Symbol_table* symtab,
1871 Target_i386* target,
1872 Sized_relobj_file<32, false>* object,
1873 unsigned int data_shndx,
1874 Output_section* output_section,
1875 const elfcpp::Rel<32, false>& reloc,
1876 unsigned int r_type,
1879 // A STT_GNU_IFUNC symbol may require a PLT entry.
1880 if (gsym->type() == elfcpp::STT_GNU_IFUNC
1881 && this->reloc_needs_plt_for_ifunc(object, r_type))
1882 target->make_plt_entry(symtab, layout, gsym);
1886 case elfcpp::R_386_NONE:
1887 case elfcpp::R_386_GNU_VTINHERIT:
1888 case elfcpp::R_386_GNU_VTENTRY:
1891 case elfcpp::R_386_32:
1892 case elfcpp::R_386_16:
1893 case elfcpp::R_386_8:
1895 // Make a PLT entry if necessary.
1896 if (gsym->needs_plt_entry())
1898 target->make_plt_entry(symtab, layout, gsym);
1899 // Since this is not a PC-relative relocation, we may be
1900 // taking the address of a function. In that case we need to
1901 // set the entry in the dynamic symbol table to the address of
1903 if (gsym->is_from_dynobj() && !parameters->options().shared())
1904 gsym->set_needs_dynsym_value();
1906 // Make a dynamic relocation if necessary.
1907 if (gsym->needs_dynamic_reloc(Scan::get_reference_flags(r_type)))
1909 if (gsym->may_need_copy_reloc())
1911 target->copy_reloc(symtab, layout, object,
1912 data_shndx, output_section, gsym, reloc);
1914 else if (r_type == elfcpp::R_386_32
1915 && gsym->type() == elfcpp::STT_GNU_IFUNC
1916 && gsym->can_use_relative_reloc(false)
1917 && !gsym->is_from_dynobj()
1918 && !gsym->is_undefined()
1919 && !gsym->is_preemptible())
1921 // Use an IRELATIVE reloc for a locally defined
1922 // STT_GNU_IFUNC symbol. This makes a function
1923 // address in a PIE executable match the address in a
1924 // shared library that it links against.
1925 Reloc_section* rel_dyn = target->rel_irelative_section(layout);
1926 rel_dyn->add_symbolless_global_addend(gsym,
1927 elfcpp::R_386_IRELATIVE,
1930 reloc.get_r_offset());
1932 else if (r_type == elfcpp::R_386_32
1933 && gsym->can_use_relative_reloc(false))
1935 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1936 rel_dyn->add_global_relative(gsym, elfcpp::R_386_RELATIVE,
1937 output_section, object,
1938 data_shndx, reloc.get_r_offset());
1942 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1943 rel_dyn->add_global(gsym, r_type, output_section, object,
1944 data_shndx, reloc.get_r_offset());
1950 case elfcpp::R_386_PC32:
1951 case elfcpp::R_386_PC16:
1952 case elfcpp::R_386_PC8:
1954 // Make a PLT entry if necessary.
1955 if (gsym->needs_plt_entry())
1957 // These relocations are used for function calls only in
1958 // non-PIC code. For a 32-bit relocation in a shared library,
1959 // we'll need a text relocation anyway, so we can skip the
1960 // PLT entry and let the dynamic linker bind the call directly
1961 // to the target. For smaller relocations, we should use a
1962 // PLT entry to ensure that the call can reach.
1963 if (!parameters->options().shared()
1964 || r_type != elfcpp::R_386_PC32)
1965 target->make_plt_entry(symtab, layout, gsym);
1967 // Make a dynamic relocation if necessary.
1968 if (gsym->needs_dynamic_reloc(Scan::get_reference_flags(r_type)))
1970 if (gsym->may_need_copy_reloc())
1972 target->copy_reloc(symtab, layout, object,
1973 data_shndx, output_section, gsym, reloc);
1977 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
1978 rel_dyn->add_global(gsym, r_type, output_section, object,
1979 data_shndx, reloc.get_r_offset());
1985 case elfcpp::R_386_GOT32:
1987 // The symbol requires a GOT entry.
1988 Output_data_got<32, false>* got = target->got_section(symtab, layout);
1989 if (gsym->final_value_is_known())
1991 // For a STT_GNU_IFUNC symbol we want the PLT address.
1992 if (gsym->type() == elfcpp::STT_GNU_IFUNC)
1993 got->add_global_plt(gsym, GOT_TYPE_STANDARD);
1995 got->add_global(gsym, GOT_TYPE_STANDARD);
1999 // If this symbol is not fully resolved, we need to add a
2000 // GOT entry with a dynamic relocation.
2001 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
2003 // Use a GLOB_DAT rather than a RELATIVE reloc if:
2005 // 1) The symbol may be defined in some other module.
2007 // 2) We are building a shared library and this is a
2008 // protected symbol; using GLOB_DAT means that the dynamic
2009 // linker can use the address of the PLT in the main
2010 // executable when appropriate so that function address
2011 // comparisons work.
2013 // 3) This is a STT_GNU_IFUNC symbol in position dependent
2014 // code, again so that function address comparisons work.
2015 if (gsym->is_from_dynobj()
2016 || gsym->is_undefined()
2017 || gsym->is_preemptible()
2018 || (gsym->visibility() == elfcpp::STV_PROTECTED
2019 && parameters->options().shared())
2020 || (gsym->type() == elfcpp::STT_GNU_IFUNC
2021 && parameters->options().output_is_position_independent()))
2022 got->add_global_with_rel(gsym, GOT_TYPE_STANDARD,
2023 rel_dyn, elfcpp::R_386_GLOB_DAT);
2026 // For a STT_GNU_IFUNC symbol we want to write the PLT
2027 // offset into the GOT, so that function pointer
2028 // comparisons work correctly.
2030 if (gsym->type() != elfcpp::STT_GNU_IFUNC)
2031 is_new = got->add_global(gsym, GOT_TYPE_STANDARD);
2034 is_new = got->add_global_plt(gsym, GOT_TYPE_STANDARD);
2035 // Tell the dynamic linker to use the PLT address
2036 // when resolving relocations.
2037 if (gsym->is_from_dynobj()
2038 && !parameters->options().shared())
2039 gsym->set_needs_dynsym_value();
2043 unsigned int got_off = gsym->got_offset(GOT_TYPE_STANDARD);
2044 rel_dyn->add_global_relative(gsym, elfcpp::R_386_RELATIVE,
2052 case elfcpp::R_386_PLT32:
2053 // If the symbol is fully resolved, this is just a PC32 reloc.
2054 // Otherwise we need a PLT entry.
2055 if (gsym->final_value_is_known())
2057 // If building a shared library, we can also skip the PLT entry
2058 // if the symbol is defined in the output file and is protected
2060 if (gsym->is_defined()
2061 && !gsym->is_from_dynobj()
2062 && !gsym->is_preemptible())
2064 target->make_plt_entry(symtab, layout, gsym);
2067 case elfcpp::R_386_GOTOFF:
2068 case elfcpp::R_386_GOTPC:
2069 // We need a GOT section.
2070 target->got_section(symtab, layout);
2073 // These are relocations which should only be seen by the
2074 // dynamic linker, and should never be seen here.
2075 case elfcpp::R_386_COPY:
2076 case elfcpp::R_386_GLOB_DAT:
2077 case elfcpp::R_386_JUMP_SLOT:
2078 case elfcpp::R_386_RELATIVE:
2079 case elfcpp::R_386_IRELATIVE:
2080 case elfcpp::R_386_TLS_TPOFF:
2081 case elfcpp::R_386_TLS_DTPMOD32:
2082 case elfcpp::R_386_TLS_DTPOFF32:
2083 case elfcpp::R_386_TLS_TPOFF32:
2084 case elfcpp::R_386_TLS_DESC:
2085 gold_error(_("%s: unexpected reloc %u in object file"),
2086 object->name().c_str(), r_type);
2089 // These are initial tls relocs, which are expected when
2091 case elfcpp::R_386_TLS_GD: // Global-dynamic
2092 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url)
2093 case elfcpp::R_386_TLS_DESC_CALL:
2094 case elfcpp::R_386_TLS_LDM: // Local-dynamic
2095 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
2096 case elfcpp::R_386_TLS_IE: // Initial-exec
2097 case elfcpp::R_386_TLS_IE_32:
2098 case elfcpp::R_386_TLS_GOTIE:
2099 case elfcpp::R_386_TLS_LE: // Local-exec
2100 case elfcpp::R_386_TLS_LE_32:
2102 const bool is_final = gsym->final_value_is_known();
2103 const tls::Tls_optimization optimized_type
2104 = Target_i386::optimize_tls_reloc(is_final, r_type);
2107 case elfcpp::R_386_TLS_GD: // Global-dynamic
2108 if (optimized_type == tls::TLSOPT_NONE)
2110 // Create a pair of GOT entries for the module index and
2111 // dtv-relative offset.
2112 Output_data_got<32, false>* got
2113 = target->got_section(symtab, layout);
2114 got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_PAIR,
2115 target->rel_dyn_section(layout),
2116 elfcpp::R_386_TLS_DTPMOD32,
2117 elfcpp::R_386_TLS_DTPOFF32);
2119 else if (optimized_type == tls::TLSOPT_TO_IE)
2121 // Create a GOT entry for the tp-relative offset.
2122 Output_data_got<32, false>* got
2123 = target->got_section(symtab, layout);
2124 got->add_global_with_rel(gsym, GOT_TYPE_TLS_NOFFSET,
2125 target->rel_dyn_section(layout),
2126 elfcpp::R_386_TLS_TPOFF);
2128 else if (optimized_type != tls::TLSOPT_TO_LE)
2129 unsupported_reloc_global(object, r_type, gsym);
2132 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (~oliva url)
2133 target->define_tls_base_symbol(symtab, layout);
2134 if (optimized_type == tls::TLSOPT_NONE)
2136 // Create a double GOT entry with an R_386_TLS_DESC
2137 // reloc. The R_386_TLS_DESC reloc is resolved
2138 // lazily, so the GOT entry needs to be in an area in
2139 // .got.plt, not .got. Call got_section to make sure
2140 // the section has been created.
2141 target->got_section(symtab, layout);
2142 Output_data_got<32, false>* got = target->got_tlsdesc_section();
2143 Reloc_section* rt = target->rel_tls_desc_section(layout);
2144 got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_DESC, rt,
2145 elfcpp::R_386_TLS_DESC, 0);
2147 else if (optimized_type == tls::TLSOPT_TO_IE)
2149 // Create a GOT entry for the tp-relative offset.
2150 Output_data_got<32, false>* got
2151 = target->got_section(symtab, layout);
2152 got->add_global_with_rel(gsym, GOT_TYPE_TLS_NOFFSET,
2153 target->rel_dyn_section(layout),
2154 elfcpp::R_386_TLS_TPOFF);
2156 else if (optimized_type != tls::TLSOPT_TO_LE)
2157 unsupported_reloc_global(object, r_type, gsym);
2160 case elfcpp::R_386_TLS_DESC_CALL:
2163 case elfcpp::R_386_TLS_LDM: // Local-dynamic
2164 if (optimized_type == tls::TLSOPT_NONE)
2166 // Create a GOT entry for the module index.
2167 target->got_mod_index_entry(symtab, layout, object);
2169 else if (optimized_type != tls::TLSOPT_TO_LE)
2170 unsupported_reloc_global(object, r_type, gsym);
2173 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
2176 case elfcpp::R_386_TLS_IE: // Initial-exec
2177 case elfcpp::R_386_TLS_IE_32:
2178 case elfcpp::R_386_TLS_GOTIE:
2179 layout->set_has_static_tls();
2180 if (optimized_type == tls::TLSOPT_NONE)
2182 // For the R_386_TLS_IE relocation, we need to create a
2183 // dynamic relocation when building a shared library.
2184 if (r_type == elfcpp::R_386_TLS_IE
2185 && parameters->options().shared())
2187 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
2188 rel_dyn->add_global_relative(gsym, elfcpp::R_386_RELATIVE,
2189 output_section, object,
2191 reloc.get_r_offset());
2193 // Create a GOT entry for the tp-relative offset.
2194 Output_data_got<32, false>* got
2195 = target->got_section(symtab, layout);
2196 unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_IE_32
2197 ? elfcpp::R_386_TLS_TPOFF32
2198 : elfcpp::R_386_TLS_TPOFF);
2199 unsigned int got_type = (r_type == elfcpp::R_386_TLS_IE_32
2200 ? GOT_TYPE_TLS_OFFSET
2201 : GOT_TYPE_TLS_NOFFSET);
2202 got->add_global_with_rel(gsym, got_type,
2203 target->rel_dyn_section(layout),
2206 else if (optimized_type != tls::TLSOPT_TO_LE)
2207 unsupported_reloc_global(object, r_type, gsym);
2210 case elfcpp::R_386_TLS_LE: // Local-exec
2211 case elfcpp::R_386_TLS_LE_32:
2212 layout->set_has_static_tls();
2213 if (parameters->options().shared())
2215 // We need to create a dynamic relocation.
2216 unsigned int dyn_r_type = (r_type == elfcpp::R_386_TLS_LE_32
2217 ? elfcpp::R_386_TLS_TPOFF32
2218 : elfcpp::R_386_TLS_TPOFF);
2219 Reloc_section* rel_dyn = target->rel_dyn_section(layout);
2220 rel_dyn->add_global(gsym, dyn_r_type, output_section, object,
2221 data_shndx, reloc.get_r_offset());
2231 case elfcpp::R_386_32PLT:
2232 case elfcpp::R_386_TLS_GD_32:
2233 case elfcpp::R_386_TLS_GD_PUSH:
2234 case elfcpp::R_386_TLS_GD_CALL:
2235 case elfcpp::R_386_TLS_GD_POP:
2236 case elfcpp::R_386_TLS_LDM_32:
2237 case elfcpp::R_386_TLS_LDM_PUSH:
2238 case elfcpp::R_386_TLS_LDM_CALL:
2239 case elfcpp::R_386_TLS_LDM_POP:
2240 case elfcpp::R_386_USED_BY_INTEL_200:
2242 unsupported_reloc_global(object, r_type, gsym);
2247 // Process relocations for gc.
2250 Target_i386::gc_process_relocs(Symbol_table* symtab,
2252 Sized_relobj_file<32, false>* object,
2253 unsigned int data_shndx,
2255 const unsigned char* prelocs,
2257 Output_section* output_section,
2258 bool needs_special_offset_handling,
2259 size_t local_symbol_count,
2260 const unsigned char* plocal_symbols)
2262 gold::gc_process_relocs<32, false, Target_i386, elfcpp::SHT_REL,
2264 Target_i386::Relocatable_size_for_reloc>(
2273 needs_special_offset_handling,
2278 // Scan relocations for a section.
2281 Target_i386::scan_relocs(Symbol_table* symtab,
2283 Sized_relobj_file<32, false>* object,
2284 unsigned int data_shndx,
2285 unsigned int sh_type,
2286 const unsigned char* prelocs,
2288 Output_section* output_section,
2289 bool needs_special_offset_handling,
2290 size_t local_symbol_count,
2291 const unsigned char* plocal_symbols)
2293 if (sh_type == elfcpp::SHT_RELA)
2295 gold_error(_("%s: unsupported RELA reloc section"),
2296 object->name().c_str());
2300 gold::scan_relocs<32, false, Target_i386, elfcpp::SHT_REL,
2310 needs_special_offset_handling,
2315 // Finalize the sections.
2318 Target_i386::do_finalize_sections(
2320 const Input_objects*,
2321 Symbol_table* symtab)
2323 const Reloc_section* rel_plt = (this->plt_ == NULL
2325 : this->plt_->rel_plt());
2326 layout->add_target_dynamic_tags(true, this->got_plt_, rel_plt,
2327 this->rel_dyn_, true, false);
2329 // Emit any relocs we saved in an attempt to avoid generating COPY
2331 if (this->copy_relocs_.any_saved_relocs())
2332 this->copy_relocs_.emit(this->rel_dyn_section(layout));
2334 // Set the size of the _GLOBAL_OFFSET_TABLE_ symbol to the size of
2335 // the .got.plt section.
2336 Symbol* sym = this->global_offset_table_;
2339 uint32_t data_size = this->got_plt_->current_data_size();
2340 symtab->get_sized_symbol<32>(sym)->set_symsize(data_size);
2343 if (parameters->doing_static_link()
2344 && (this->plt_ == NULL || !this->plt_->has_irelative_section()))
2346 // If linking statically, make sure that the __rel_iplt symbols
2347 // were defined if necessary, even if we didn't create a PLT.
2348 static const Define_symbol_in_segment syms[] =
2351 "__rel_iplt_start", // name
2352 elfcpp::PT_LOAD, // segment_type
2353 elfcpp::PF_W, // segment_flags_set
2354 elfcpp::PF(0), // segment_flags_clear
2357 elfcpp::STT_NOTYPE, // type
2358 elfcpp::STB_GLOBAL, // binding
2359 elfcpp::STV_HIDDEN, // visibility
2361 Symbol::SEGMENT_START, // offset_from_base
2365 "__rel_iplt_end", // name
2366 elfcpp::PT_LOAD, // segment_type
2367 elfcpp::PF_W, // segment_flags_set
2368 elfcpp::PF(0), // segment_flags_clear
2371 elfcpp::STT_NOTYPE, // type
2372 elfcpp::STB_GLOBAL, // binding
2373 elfcpp::STV_HIDDEN, // visibility
2375 Symbol::SEGMENT_START, // offset_from_base
2380 symtab->define_symbols(layout, 2, syms,
2381 layout->script_options()->saw_sections_clause());
2385 // Return whether a direct absolute static relocation needs to be applied.
2386 // In cases where Scan::local() or Scan::global() has created
2387 // a dynamic relocation other than R_386_RELATIVE, the addend
2388 // of the relocation is carried in the data, and we must not
2389 // apply the static relocation.
2392 Target_i386::Relocate::should_apply_static_reloc(const Sized_symbol<32>* gsym,
2393 unsigned int r_type,
2395 Output_section* output_section)
2397 // If the output section is not allocated, then we didn't call
2398 // scan_relocs, we didn't create a dynamic reloc, and we must apply
2400 if ((output_section->flags() & elfcpp::SHF_ALLOC) == 0)
2403 int ref_flags = Scan::get_reference_flags(r_type);
2405 // For local symbols, we will have created a non-RELATIVE dynamic
2406 // relocation only if (a) the output is position independent,
2407 // (b) the relocation is absolute (not pc- or segment-relative), and
2408 // (c) the relocation is not 32 bits wide.
2410 return !(parameters->options().output_is_position_independent()
2411 && (ref_flags & Symbol::ABSOLUTE_REF)
2414 // For global symbols, we use the same helper routines used in the
2415 // scan pass. If we did not create a dynamic relocation, or if we
2416 // created a RELATIVE dynamic relocation, we should apply the static
2418 bool has_dyn = gsym->needs_dynamic_reloc(ref_flags);
2419 bool is_rel = (ref_flags & Symbol::ABSOLUTE_REF)
2420 && gsym->can_use_relative_reloc(ref_flags
2421 & Symbol::FUNCTION_CALL);
2422 return !has_dyn || is_rel;
2425 // Perform a relocation.
2428 Target_i386::Relocate::relocate(const Relocate_info<32, false>* relinfo,
2429 Target_i386* target,
2430 Output_section* output_section,
2432 const elfcpp::Rel<32, false>& rel,
2433 unsigned int r_type,
2434 const Sized_symbol<32>* gsym,
2435 const Symbol_value<32>* psymval,
2436 unsigned char* view,
2437 elfcpp::Elf_types<32>::Elf_Addr address,
2438 section_size_type view_size)
2440 if (this->skip_call_tls_get_addr_)
2442 if ((r_type != elfcpp::R_386_PLT32
2443 && r_type != elfcpp::R_386_PC32)
2445 || strcmp(gsym->name(), "___tls_get_addr") != 0)
2446 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
2447 _("missing expected TLS relocation"));
2450 this->skip_call_tls_get_addr_ = false;
2455 const Sized_relobj_file<32, false>* object = relinfo->object;
2457 // Pick the value to use for symbols defined in shared objects.
2458 Symbol_value<32> symval;
2460 && gsym->type() == elfcpp::STT_GNU_IFUNC
2461 && r_type == elfcpp::R_386_32
2462 && gsym->needs_dynamic_reloc(Scan::get_reference_flags(r_type))
2463 && gsym->can_use_relative_reloc(false)
2464 && !gsym->is_from_dynobj()
2465 && !gsym->is_undefined()
2466 && !gsym->is_preemptible())
2468 // In this case we are generating a R_386_IRELATIVE reloc. We
2469 // want to use the real value of the symbol, not the PLT offset.
2471 else if (gsym != NULL
2472 && gsym->use_plt_offset(Scan::get_reference_flags(r_type)))
2474 symval.set_output_value(target->plt_address_for_global(gsym)
2475 + gsym->plt_offset());
2478 else if (gsym == NULL && psymval->is_ifunc_symbol())
2480 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
2481 if (object->local_has_plt_offset(r_sym))
2483 symval.set_output_value(target->plt_address_for_local(object, r_sym)
2484 + object->local_plt_offset(r_sym));
2489 // Get the GOT offset if needed.
2490 // The GOT pointer points to the end of the GOT section.
2491 // We need to subtract the size of the GOT section to get
2492 // the actual offset to use in the relocation.
2493 bool have_got_offset = false;
2494 unsigned int got_offset = 0;
2497 case elfcpp::R_386_GOT32:
2500 gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
2501 got_offset = (gsym->got_offset(GOT_TYPE_STANDARD)
2502 - target->got_size());
2506 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
2507 gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD));
2508 got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD)
2509 - target->got_size());
2511 have_got_offset = true;
2520 case elfcpp::R_386_NONE:
2521 case elfcpp::R_386_GNU_VTINHERIT:
2522 case elfcpp::R_386_GNU_VTENTRY:
2525 case elfcpp::R_386_32:
2526 if (should_apply_static_reloc(gsym, r_type, true, output_section))
2527 Relocate_functions<32, false>::rel32(view, object, psymval);
2530 case elfcpp::R_386_PC32:
2531 if (should_apply_static_reloc(gsym, r_type, true, output_section))
2532 Relocate_functions<32, false>::pcrel32(view, object, psymval, address);
2535 case elfcpp::R_386_16:
2536 if (should_apply_static_reloc(gsym, r_type, false, output_section))
2537 Relocate_functions<32, false>::rel16(view, object, psymval);
2540 case elfcpp::R_386_PC16:
2541 if (should_apply_static_reloc(gsym, r_type, false, output_section))
2542 Relocate_functions<32, false>::pcrel16(view, object, psymval, address);
2545 case elfcpp::R_386_8:
2546 if (should_apply_static_reloc(gsym, r_type, false, output_section))
2547 Relocate_functions<32, false>::rel8(view, object, psymval);
2550 case elfcpp::R_386_PC8:
2551 if (should_apply_static_reloc(gsym, r_type, false, output_section))
2552 Relocate_functions<32, false>::pcrel8(view, object, psymval, address);
2555 case elfcpp::R_386_PLT32:
2556 gold_assert(gsym == NULL
2557 || gsym->has_plt_offset()
2558 || gsym->final_value_is_known()
2559 || (gsym->is_defined()
2560 && !gsym->is_from_dynobj()
2561 && !gsym->is_preemptible()));
2562 Relocate_functions<32, false>::pcrel32(view, object, psymval, address);
2565 case elfcpp::R_386_GOT32:
2566 gold_assert(have_got_offset);
2567 Relocate_functions<32, false>::rel32(view, got_offset);
2570 case elfcpp::R_386_GOTOFF:
2572 elfcpp::Elf_types<32>::Elf_Addr value;
2573 value = (psymval->value(object, 0)
2574 - target->got_plt_section()->address());
2575 Relocate_functions<32, false>::rel32(view, value);
2579 case elfcpp::R_386_GOTPC:
2581 elfcpp::Elf_types<32>::Elf_Addr value;
2582 value = target->got_plt_section()->address();
2583 Relocate_functions<32, false>::pcrel32(view, value, address);
2587 case elfcpp::R_386_COPY:
2588 case elfcpp::R_386_GLOB_DAT:
2589 case elfcpp::R_386_JUMP_SLOT:
2590 case elfcpp::R_386_RELATIVE:
2591 case elfcpp::R_386_IRELATIVE:
2592 // These are outstanding tls relocs, which are unexpected when
2594 case elfcpp::R_386_TLS_TPOFF:
2595 case elfcpp::R_386_TLS_DTPMOD32:
2596 case elfcpp::R_386_TLS_DTPOFF32:
2597 case elfcpp::R_386_TLS_TPOFF32:
2598 case elfcpp::R_386_TLS_DESC:
2599 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
2600 _("unexpected reloc %u in object file"),
2604 // These are initial tls relocs, which are expected when
2606 case elfcpp::R_386_TLS_GD: // Global-dynamic
2607 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url)
2608 case elfcpp::R_386_TLS_DESC_CALL:
2609 case elfcpp::R_386_TLS_LDM: // Local-dynamic
2610 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
2611 case elfcpp::R_386_TLS_IE: // Initial-exec
2612 case elfcpp::R_386_TLS_IE_32:
2613 case elfcpp::R_386_TLS_GOTIE:
2614 case elfcpp::R_386_TLS_LE: // Local-exec
2615 case elfcpp::R_386_TLS_LE_32:
2616 this->relocate_tls(relinfo, target, relnum, rel, r_type, gsym, psymval,
2617 view, address, view_size);
2620 case elfcpp::R_386_32PLT:
2621 case elfcpp::R_386_TLS_GD_32:
2622 case elfcpp::R_386_TLS_GD_PUSH:
2623 case elfcpp::R_386_TLS_GD_CALL:
2624 case elfcpp::R_386_TLS_GD_POP:
2625 case elfcpp::R_386_TLS_LDM_32:
2626 case elfcpp::R_386_TLS_LDM_PUSH:
2627 case elfcpp::R_386_TLS_LDM_CALL:
2628 case elfcpp::R_386_TLS_LDM_POP:
2629 case elfcpp::R_386_USED_BY_INTEL_200:
2631 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
2632 _("unsupported reloc %u"),
2640 // Perform a TLS relocation.
2643 Target_i386::Relocate::relocate_tls(const Relocate_info<32, false>* relinfo,
2644 Target_i386* target,
2646 const elfcpp::Rel<32, false>& rel,
2647 unsigned int r_type,
2648 const Sized_symbol<32>* gsym,
2649 const Symbol_value<32>* psymval,
2650 unsigned char* view,
2651 elfcpp::Elf_types<32>::Elf_Addr,
2652 section_size_type view_size)
2654 Output_segment* tls_segment = relinfo->layout->tls_segment();
2656 const Sized_relobj_file<32, false>* object = relinfo->object;
2658 elfcpp::Elf_types<32>::Elf_Addr value = psymval->value(object, 0);
2660 const bool is_final = (gsym == NULL
2661 ? !parameters->options().shared()
2662 : gsym->final_value_is_known());
2663 const tls::Tls_optimization optimized_type
2664 = Target_i386::optimize_tls_reloc(is_final, r_type);
2667 case elfcpp::R_386_TLS_GD: // Global-dynamic
2668 if (optimized_type == tls::TLSOPT_TO_LE)
2670 if (tls_segment == NULL)
2672 gold_assert(parameters->errors()->error_count() > 0
2673 || issue_undefined_symbol_error(gsym));
2676 this->tls_gd_to_le(relinfo, relnum, tls_segment,
2677 rel, r_type, value, view,
2683 unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE
2684 ? GOT_TYPE_TLS_NOFFSET
2685 : GOT_TYPE_TLS_PAIR);
2686 unsigned int got_offset;
2689 gold_assert(gsym->has_got_offset(got_type));
2690 got_offset = gsym->got_offset(got_type) - target->got_size();
2694 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
2695 gold_assert(object->local_has_got_offset(r_sym, got_type));
2696 got_offset = (object->local_got_offset(r_sym, got_type)
2697 - target->got_size());
2699 if (optimized_type == tls::TLSOPT_TO_IE)
2701 if (tls_segment == NULL)
2703 gold_assert(parameters->errors()->error_count() > 0
2704 || issue_undefined_symbol_error(gsym));
2707 this->tls_gd_to_ie(relinfo, relnum, tls_segment, rel, r_type,
2708 got_offset, view, view_size);
2711 else if (optimized_type == tls::TLSOPT_NONE)
2713 // Relocate the field with the offset of the pair of GOT
2715 Relocate_functions<32, false>::rel32(view, got_offset);
2719 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
2720 _("unsupported reloc %u"),
2724 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url)
2725 case elfcpp::R_386_TLS_DESC_CALL:
2726 this->local_dynamic_type_ = LOCAL_DYNAMIC_GNU;
2727 if (optimized_type == tls::TLSOPT_TO_LE)
2729 if (tls_segment == NULL)
2731 gold_assert(parameters->errors()->error_count() > 0
2732 || issue_undefined_symbol_error(gsym));
2735 this->tls_desc_gd_to_le(relinfo, relnum, tls_segment,
2736 rel, r_type, value, view,
2742 unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE
2743 ? GOT_TYPE_TLS_NOFFSET
2744 : GOT_TYPE_TLS_DESC);
2745 unsigned int got_offset = 0;
2746 if (r_type == elfcpp::R_386_TLS_GOTDESC
2747 && optimized_type == tls::TLSOPT_NONE)
2749 // We created GOT entries in the .got.tlsdesc portion of
2750 // the .got.plt section, but the offset stored in the
2751 // symbol is the offset within .got.tlsdesc.
2752 got_offset = (target->got_size()
2753 + target->got_plt_section()->data_size());
2757 gold_assert(gsym->has_got_offset(got_type));
2758 got_offset += gsym->got_offset(got_type) - target->got_size();
2762 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
2763 gold_assert(object->local_has_got_offset(r_sym, got_type));
2764 got_offset += (object->local_got_offset(r_sym, got_type)
2765 - target->got_size());
2767 if (optimized_type == tls::TLSOPT_TO_IE)
2769 if (tls_segment == NULL)
2771 gold_assert(parameters->errors()->error_count() > 0
2772 || issue_undefined_symbol_error(gsym));
2775 this->tls_desc_gd_to_ie(relinfo, relnum, tls_segment, rel, r_type,
2776 got_offset, view, view_size);
2779 else if (optimized_type == tls::TLSOPT_NONE)
2781 if (r_type == elfcpp::R_386_TLS_GOTDESC)
2783 // Relocate the field with the offset of the pair of GOT
2785 Relocate_functions<32, false>::rel32(view, got_offset);
2790 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
2791 _("unsupported reloc %u"),
2795 case elfcpp::R_386_TLS_LDM: // Local-dynamic
2796 if (this->local_dynamic_type_ == LOCAL_DYNAMIC_SUN)
2798 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
2799 _("both SUN and GNU model "
2800 "TLS relocations"));
2803 this->local_dynamic_type_ = LOCAL_DYNAMIC_GNU;
2804 if (optimized_type == tls::TLSOPT_TO_LE)
2806 if (tls_segment == NULL)
2808 gold_assert(parameters->errors()->error_count() > 0
2809 || issue_undefined_symbol_error(gsym));
2812 this->tls_ld_to_le(relinfo, relnum, tls_segment, rel, r_type,
2813 value, view, view_size);
2816 else if (optimized_type == tls::TLSOPT_NONE)
2818 // Relocate the field with the offset of the GOT entry for
2819 // the module index.
2820 unsigned int got_offset;
2821 got_offset = (target->got_mod_index_entry(NULL, NULL, NULL)
2822 - target->got_size());
2823 Relocate_functions<32, false>::rel32(view, got_offset);
2826 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
2827 _("unsupported reloc %u"),
2831 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
2832 if (optimized_type == tls::TLSOPT_TO_LE)
2834 // This reloc can appear in debugging sections, in which
2835 // case we must not convert to local-exec. We decide what
2836 // to do based on whether the section is marked as
2837 // containing executable code. That is what the GNU linker
2839 elfcpp::Shdr<32, false> shdr(relinfo->data_shdr);
2840 if ((shdr.get_sh_flags() & elfcpp::SHF_EXECINSTR) != 0)
2842 if (tls_segment == NULL)
2844 gold_assert(parameters->errors()->error_count() > 0
2845 || issue_undefined_symbol_error(gsym));
2848 value -= tls_segment->memsz();
2851 Relocate_functions<32, false>::rel32(view, value);
2854 case elfcpp::R_386_TLS_IE: // Initial-exec
2855 case elfcpp::R_386_TLS_GOTIE:
2856 case elfcpp::R_386_TLS_IE_32:
2857 if (optimized_type == tls::TLSOPT_TO_LE)
2859 if (tls_segment == NULL)
2861 gold_assert(parameters->errors()->error_count() > 0
2862 || issue_undefined_symbol_error(gsym));
2865 Target_i386::Relocate::tls_ie_to_le(relinfo, relnum, tls_segment,
2866 rel, r_type, value, view,
2870 else if (optimized_type == tls::TLSOPT_NONE)
2872 // Relocate the field with the offset of the GOT entry for
2873 // the tp-relative offset of the symbol.
2874 unsigned int got_type = (r_type == elfcpp::R_386_TLS_IE_32
2875 ? GOT_TYPE_TLS_OFFSET
2876 : GOT_TYPE_TLS_NOFFSET);
2877 unsigned int got_offset;
2880 gold_assert(gsym->has_got_offset(got_type));
2881 got_offset = gsym->got_offset(got_type);
2885 unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.get_r_info());
2886 gold_assert(object->local_has_got_offset(r_sym, got_type));
2887 got_offset = object->local_got_offset(r_sym, got_type);
2889 // For the R_386_TLS_IE relocation, we need to apply the
2890 // absolute address of the GOT entry.
2891 if (r_type == elfcpp::R_386_TLS_IE)
2892 got_offset += target->got_plt_section()->address();
2893 // All GOT offsets are relative to the end of the GOT.
2894 got_offset -= target->got_size();
2895 Relocate_functions<32, false>::rel32(view, got_offset);
2898 gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
2899 _("unsupported reloc %u"),
2903 case elfcpp::R_386_TLS_LE: // Local-exec
2904 // If we're creating a shared library, a dynamic relocation will
2905 // have been created for this location, so do not apply it now.
2906 if (!parameters->options().shared())
2908 if (tls_segment == NULL)
2910 gold_assert(parameters->errors()->error_count() > 0
2911 || issue_undefined_symbol_error(gsym));
2914 value -= tls_segment->memsz();
2915 Relocate_functions<32, false>::rel32(view, value);
2919 case elfcpp::R_386_TLS_LE_32:
2920 // If we're creating a shared library, a dynamic relocation will
2921 // have been created for this location, so do not apply it now.
2922 if (!parameters->options().shared())
2924 if (tls_segment == NULL)
2926 gold_assert(parameters->errors()->error_count() > 0
2927 || issue_undefined_symbol_error(gsym));
2930 value = tls_segment->memsz() - value;
2931 Relocate_functions<32, false>::rel32(view, value);
2937 // Do a relocation in which we convert a TLS General-Dynamic to a
2941 Target_i386::Relocate::tls_gd_to_le(const Relocate_info<32, false>* relinfo,
2943 Output_segment* tls_segment,
2944 const elfcpp::Rel<32, false>& rel,
2946 elfcpp::Elf_types<32>::Elf_Addr value,
2947 unsigned char* view,
2948 section_size_type view_size)
2950 // leal foo(,%reg,1),%eax; call ___tls_get_addr
2951 // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
2952 // leal foo(%reg),%eax; call ___tls_get_addr
2953 // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
2955 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
2956 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 9);
2958 unsigned char op1 = view[-1];
2959 unsigned char op2 = view[-2];
2961 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2962 op2 == 0x8d || op2 == 0x04);
2963 tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[4] == 0xe8);
2969 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -3);
2970 tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[-3] == 0x8d);
2971 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2972 ((op1 & 0xc7) == 0x05 && op1 != (4 << 3)));
2973 memcpy(view - 3, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
2977 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
2978 (op1 & 0xf8) == 0x80 && (op1 & 7) != 4);
2979 if (rel.get_r_offset() + 9 < view_size
2982 // There is a trailing nop. Use the size byte subl.
2983 memcpy(view - 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
2988 // Use the five byte subl.
2989 memcpy(view - 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
2993 value = tls_segment->memsz() - value;
2994 Relocate_functions<32, false>::rel32(view + roff, value);
2996 // The next reloc should be a PLT32 reloc against __tls_get_addr.
2998 this->skip_call_tls_get_addr_ = true;
3001 // Do a relocation in which we convert a TLS General-Dynamic to an
3005 Target_i386::Relocate::tls_gd_to_ie(const Relocate_info<32, false>* relinfo,
3008 const elfcpp::Rel<32, false>& rel,
3010 elfcpp::Elf_types<32>::Elf_Addr value,
3011 unsigned char* view,
3012 section_size_type view_size)
3014 // leal foo(,%ebx,1),%eax; call ___tls_get_addr
3015 // ==> movl %gs:0,%eax; addl foo@gotntpoff(%ebx),%eax
3017 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
3018 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 9);
3020 unsigned char op1 = view[-1];
3021 unsigned char op2 = view[-2];
3023 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3024 op2 == 0x8d || op2 == 0x04);
3025 tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[4] == 0xe8);
3029 // FIXME: For now, support only the first (SIB) form.
3030 tls::check_tls(relinfo, relnum, rel.get_r_offset(), op2 == 0x04);
3034 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -3);
3035 tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[-3] == 0x8d);
3036 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3037 ((op1 & 0xc7) == 0x05 && op1 != (4 << 3)));
3038 memcpy(view - 3, "\x65\xa1\0\0\0\0\x03\x83\0\0\0", 12);
3042 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3043 (op1 & 0xf8) == 0x80 && (op1 & 7) != 4);
3044 if (rel.get_r_offset() + 9 < view_size
3047 // FIXME: This is not the right instruction sequence.
3048 // There is a trailing nop. Use the size byte subl.
3049 memcpy(view - 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
3054 // FIXME: This is not the right instruction sequence.
3055 // Use the five byte subl.
3056 memcpy(view - 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
3060 Relocate_functions<32, false>::rel32(view + roff, value);
3062 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3064 this->skip_call_tls_get_addr_ = true;
3067 // Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL
3068 // General-Dynamic to a Local-Exec.
3071 Target_i386::Relocate::tls_desc_gd_to_le(
3072 const Relocate_info<32, false>* relinfo,
3074 Output_segment* tls_segment,
3075 const elfcpp::Rel<32, false>& rel,
3076 unsigned int r_type,
3077 elfcpp::Elf_types<32>::Elf_Addr value,
3078 unsigned char* view,
3079 section_size_type view_size)
3081 if (r_type == elfcpp::R_386_TLS_GOTDESC)
3083 // leal foo@TLSDESC(%ebx), %eax
3084 // ==> leal foo@NTPOFF, %eax
3085 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
3086 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4);
3087 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3088 view[-2] == 0x8d && view[-1] == 0x83);
3090 value -= tls_segment->memsz();
3091 Relocate_functions<32, false>::rel32(view, value);
3095 // call *foo@TLSCALL(%eax)
3097 gold_assert(r_type == elfcpp::R_386_TLS_DESC_CALL);
3098 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 2);
3099 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3100 view[0] == 0xff && view[1] == 0x10);
3106 // Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL
3107 // General-Dynamic to an Initial-Exec.
3110 Target_i386::Relocate::tls_desc_gd_to_ie(
3111 const Relocate_info<32, false>* relinfo,
3114 const elfcpp::Rel<32, false>& rel,
3115 unsigned int r_type,
3116 elfcpp::Elf_types<32>::Elf_Addr value,
3117 unsigned char* view,
3118 section_size_type view_size)
3120 if (r_type == elfcpp::R_386_TLS_GOTDESC)
3122 // leal foo@TLSDESC(%ebx), %eax
3123 // ==> movl foo@GOTNTPOFF(%ebx), %eax
3124 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
3125 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4);
3126 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3127 view[-2] == 0x8d && view[-1] == 0x83);
3129 Relocate_functions<32, false>::rel32(view, value);
3133 // call *foo@TLSCALL(%eax)
3135 gold_assert(r_type == elfcpp::R_386_TLS_DESC_CALL);
3136 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 2);
3137 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3138 view[0] == 0xff && view[1] == 0x10);
3144 // Do a relocation in which we convert a TLS Local-Dynamic to a
3148 Target_i386::Relocate::tls_ld_to_le(const Relocate_info<32, false>* relinfo,
3151 const elfcpp::Rel<32, false>& rel,
3153 elfcpp::Elf_types<32>::Elf_Addr,
3154 unsigned char* view,
3155 section_size_type view_size)
3157 // leal foo(%reg), %eax; call ___tls_get_addr
3158 // ==> movl %gs:0,%eax; nop; leal 0(%esi,1),%esi
3160 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
3161 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 9);
3163 // FIXME: Does this test really always pass?
3164 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3165 view[-2] == 0x8d && view[-1] == 0x83);
3167 tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[4] == 0xe8);
3169 memcpy(view - 2, "\x65\xa1\0\0\0\0\x90\x8d\x74\x26\0", 11);
3171 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3173 this->skip_call_tls_get_addr_ = true;
3176 // Do a relocation in which we convert a TLS Initial-Exec to a
3180 Target_i386::Relocate::tls_ie_to_le(const Relocate_info<32, false>* relinfo,
3182 Output_segment* tls_segment,
3183 const elfcpp::Rel<32, false>& rel,
3184 unsigned int r_type,
3185 elfcpp::Elf_types<32>::Elf_Addr value,
3186 unsigned char* view,
3187 section_size_type view_size)
3189 // We have to actually change the instructions, which means that we
3190 // need to examine the opcodes to figure out which instruction we
3192 if (r_type == elfcpp::R_386_TLS_IE)
3194 // movl %gs:XX,%eax ==> movl $YY,%eax
3195 // movl %gs:XX,%reg ==> movl $YY,%reg
3196 // addl %gs:XX,%reg ==> addl $YY,%reg
3197 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -1);
3198 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4);
3200 unsigned char op1 = view[-1];
3203 // movl XX,%eax ==> movl $YY,%eax
3208 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
3210 unsigned char op2 = view[-2];
3213 // movl XX,%reg ==> movl $YY,%reg
3214 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3215 (op1 & 0xc7) == 0x05);
3217 view[-1] = 0xc0 | ((op1 >> 3) & 7);
3219 else if (op2 == 0x03)
3221 // addl XX,%reg ==> addl $YY,%reg
3222 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3223 (op1 & 0xc7) == 0x05);
3225 view[-1] = 0xc0 | ((op1 >> 3) & 7);
3228 tls::check_tls(relinfo, relnum, rel.get_r_offset(), 0);
3233 // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2
3234 // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2
3235 // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2
3236 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
3237 tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 4);
3239 unsigned char op1 = view[-1];
3240 unsigned char op2 = view[-2];
3241 tls::check_tls(relinfo, relnum, rel.get_r_offset(),
3242 (op1 & 0xc0) == 0x80 && (op1 & 7) != 4);
3245 // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2
3247 view[-1] = 0xc0 | ((op1 >> 3) & 7);
3249 else if (op2 == 0x2b)
3251 // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2
3253 view[-1] = 0xe8 | ((op1 >> 3) & 7);
3255 else if (op2 == 0x03)
3257 // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2
3259 view[-1] = 0xc0 | ((op1 >> 3) & 7);
3262 tls::check_tls(relinfo, relnum, rel.get_r_offset(), 0);
3265 value = tls_segment->memsz() - value;
3266 if (r_type == elfcpp::R_386_TLS_IE || r_type == elfcpp::R_386_TLS_GOTIE)
3269 Relocate_functions<32, false>::rel32(view, value);
3272 // Relocate section data.
3275 Target_i386::relocate_section(const Relocate_info<32, false>* relinfo,
3276 unsigned int sh_type,
3277 const unsigned char* prelocs,
3279 Output_section* output_section,
3280 bool needs_special_offset_handling,
3281 unsigned char* view,
3282 elfcpp::Elf_types<32>::Elf_Addr address,
3283 section_size_type view_size,
3284 const Reloc_symbol_changes* reloc_symbol_changes)
3286 gold_assert(sh_type == elfcpp::SHT_REL);
3288 gold::relocate_section<32, false, Target_i386, elfcpp::SHT_REL,
3289 Target_i386::Relocate>(
3295 needs_special_offset_handling,
3299 reloc_symbol_changes);
3302 // Return the size of a relocation while scanning during a relocatable
3306 Target_i386::Relocatable_size_for_reloc::get_size_for_reloc(
3307 unsigned int r_type,
3312 case elfcpp::R_386_NONE:
3313 case elfcpp::R_386_GNU_VTINHERIT:
3314 case elfcpp::R_386_GNU_VTENTRY:
3315 case elfcpp::R_386_TLS_GD: // Global-dynamic
3316 case elfcpp::R_386_TLS_GOTDESC: // Global-dynamic (from ~oliva url)
3317 case elfcpp::R_386_TLS_DESC_CALL:
3318 case elfcpp::R_386_TLS_LDM: // Local-dynamic
3319 case elfcpp::R_386_TLS_LDO_32: // Alternate local-dynamic
3320 case elfcpp::R_386_TLS_IE: // Initial-exec
3321 case elfcpp::R_386_TLS_IE_32:
3322 case elfcpp::R_386_TLS_GOTIE:
3323 case elfcpp::R_386_TLS_LE: // Local-exec
3324 case elfcpp::R_386_TLS_LE_32:
3327 case elfcpp::R_386_32:
3328 case elfcpp::R_386_PC32:
3329 case elfcpp::R_386_GOT32:
3330 case elfcpp::R_386_PLT32:
3331 case elfcpp::R_386_GOTOFF:
3332 case elfcpp::R_386_GOTPC:
3335 case elfcpp::R_386_16:
3336 case elfcpp::R_386_PC16:
3339 case elfcpp::R_386_8:
3340 case elfcpp::R_386_PC8:
3343 // These are relocations which should only be seen by the
3344 // dynamic linker, and should never be seen here.
3345 case elfcpp::R_386_COPY:
3346 case elfcpp::R_386_GLOB_DAT:
3347 case elfcpp::R_386_JUMP_SLOT:
3348 case elfcpp::R_386_RELATIVE:
3349 case elfcpp::R_386_IRELATIVE:
3350 case elfcpp::R_386_TLS_TPOFF:
3351 case elfcpp::R_386_TLS_DTPMOD32:
3352 case elfcpp::R_386_TLS_DTPOFF32:
3353 case elfcpp::R_386_TLS_TPOFF32:
3354 case elfcpp::R_386_TLS_DESC:
3355 object->error(_("unexpected reloc %u in object file"), r_type);
3358 case elfcpp::R_386_32PLT:
3359 case elfcpp::R_386_TLS_GD_32:
3360 case elfcpp::R_386_TLS_GD_PUSH:
3361 case elfcpp::R_386_TLS_GD_CALL:
3362 case elfcpp::R_386_TLS_GD_POP:
3363 case elfcpp::R_386_TLS_LDM_32:
3364 case elfcpp::R_386_TLS_LDM_PUSH:
3365 case elfcpp::R_386_TLS_LDM_CALL:
3366 case elfcpp::R_386_TLS_LDM_POP:
3367 case elfcpp::R_386_USED_BY_INTEL_200:
3369 object->error(_("unsupported reloc %u in object file"), r_type);
3374 // Scan the relocs during a relocatable link.
3377 Target_i386::scan_relocatable_relocs(Symbol_table* symtab,
3379 Sized_relobj_file<32, false>* object,
3380 unsigned int data_shndx,
3381 unsigned int sh_type,
3382 const unsigned char* prelocs,
3384 Output_section* output_section,
3385 bool needs_special_offset_handling,
3386 size_t local_symbol_count,
3387 const unsigned char* plocal_symbols,
3388 Relocatable_relocs* rr)
3390 gold_assert(sh_type == elfcpp::SHT_REL);
3392 typedef gold::Default_scan_relocatable_relocs<elfcpp::SHT_REL,
3393 Relocatable_size_for_reloc> Scan_relocatable_relocs;
3395 gold::scan_relocatable_relocs<32, false, elfcpp::SHT_REL,
3396 Scan_relocatable_relocs>(
3404 needs_special_offset_handling,
3410 // Relocate a section during a relocatable link.
3413 Target_i386::relocate_for_relocatable(
3414 const Relocate_info<32, false>* relinfo,
3415 unsigned int sh_type,
3416 const unsigned char* prelocs,
3418 Output_section* output_section,
3419 off_t offset_in_output_section,
3420 const Relocatable_relocs* rr,
3421 unsigned char* view,
3422 elfcpp::Elf_types<32>::Elf_Addr view_address,
3423 section_size_type view_size,
3424 unsigned char* reloc_view,
3425 section_size_type reloc_view_size)
3427 gold_assert(sh_type == elfcpp::SHT_REL);
3429 gold::relocate_for_relocatable<32, false, elfcpp::SHT_REL>(
3434 offset_in_output_section,
3443 // Return the value to use for a dynamic which requires special
3444 // treatment. This is how we support equality comparisons of function
3445 // pointers across shared library boundaries, as described in the
3446 // processor specific ABI supplement.
3449 Target_i386::do_dynsym_value(const Symbol* gsym) const
3451 gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset());
3452 return this->plt_address_for_global(gsym) + gsym->plt_offset();
3455 // Return a string used to fill a code section with nops to take up
3456 // the specified length.
3459 Target_i386::do_code_fill(section_size_type length) const
3463 // Build a jmp instruction to skip over the bytes.
3464 unsigned char jmp[5];
3466 elfcpp::Swap_unaligned<32, false>::writeval(jmp + 1, length - 5);
3467 return (std::string(reinterpret_cast<char*>(&jmp[0]), 5)
3468 + std::string(length - 5, '\0'));
3471 // Nop sequences of various lengths.
3472 const char nop1[1] = { 0x90 }; // nop
3473 const char nop2[2] = { 0x66, 0x90 }; // xchg %ax %ax
3474 const char nop3[3] = { 0x8d, 0x76, 0x00 }; // leal 0(%esi),%esi
3475 const char nop4[4] = { 0x8d, 0x74, 0x26, 0x00}; // leal 0(%esi,1),%esi
3476 const char nop5[5] = { 0x90, 0x8d, 0x74, 0x26, // nop
3477 0x00 }; // leal 0(%esi,1),%esi
3478 const char nop6[6] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
3480 const char nop7[7] = { 0x8d, 0xb4, 0x26, 0x00, // leal 0L(%esi,1),%esi
3482 const char nop8[8] = { 0x90, 0x8d, 0xb4, 0x26, // nop
3483 0x00, 0x00, 0x00, 0x00 }; // leal 0L(%esi,1),%esi
3484 const char nop9[9] = { 0x89, 0xf6, 0x8d, 0xbc, // movl %esi,%esi
3485 0x27, 0x00, 0x00, 0x00, // leal 0L(%edi,1),%edi
3487 const char nop10[10] = { 0x8d, 0x76, 0x00, 0x8d, // leal 0(%esi),%esi
3488 0xbc, 0x27, 0x00, 0x00, // leal 0L(%edi,1),%edi
3490 const char nop11[11] = { 0x8d, 0x74, 0x26, 0x00, // leal 0(%esi,1),%esi
3491 0x8d, 0xbc, 0x27, 0x00, // leal 0L(%edi,1),%edi
3493 const char nop12[12] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
3494 0x00, 0x00, 0x8d, 0xbf, // leal 0L(%edi),%edi
3495 0x00, 0x00, 0x00, 0x00 };
3496 const char nop13[13] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
3497 0x00, 0x00, 0x8d, 0xbc, // leal 0L(%edi,1),%edi
3498 0x27, 0x00, 0x00, 0x00,
3500 const char nop14[14] = { 0x8d, 0xb4, 0x26, 0x00, // leal 0L(%esi,1),%esi
3501 0x00, 0x00, 0x00, 0x8d, // leal 0L(%edi,1),%edi
3502 0xbc, 0x27, 0x00, 0x00,
3504 const char nop15[15] = { 0xeb, 0x0d, 0x90, 0x90, // jmp .+15
3505 0x90, 0x90, 0x90, 0x90, // nop,nop,nop,...
3506 0x90, 0x90, 0x90, 0x90,
3509 const char* nops[16] = {
3511 nop1, nop2, nop3, nop4, nop5, nop6, nop7,
3512 nop8, nop9, nop10, nop11, nop12, nop13, nop14, nop15
3515 return std::string(nops[length], length);
3518 // Return the value to use for the base of a DW_EH_PE_datarel offset
3519 // in an FDE. Solaris and SVR4 use DW_EH_PE_datarel because their
3520 // assembler can not write out the difference between two labels in
3521 // different sections, so instead of using a pc-relative value they
3522 // use an offset from the GOT.
3525 Target_i386::do_ehframe_datarel_base() const
3527 gold_assert(this->global_offset_table_ != NULL);
3528 Symbol* sym = this->global_offset_table_;
3529 Sized_symbol<32>* ssym = static_cast<Sized_symbol<32>*>(sym);
3530 return ssym->value();
3533 // Return whether SYM should be treated as a call to a non-split
3534 // function. We don't want that to be true of a call to a
3535 // get_pc_thunk function.
3538 Target_i386::do_is_call_to_non_split(const Symbol* sym, unsigned int) const
3540 return (sym->type() == elfcpp::STT_FUNC
3541 && !is_prefix_of("__i686.get_pc_thunk.", sym->name()));
3544 // FNOFFSET in section SHNDX in OBJECT is the start of a function
3545 // compiled with -fsplit-stack. The function calls non-split-stack
3546 // code. We have to change the function so that it always ensures
3547 // that it has enough stack space to run some random function.
3550 Target_i386::do_calls_non_split(Relobj* object, unsigned int shndx,
3551 section_offset_type fnoffset,
3552 section_size_type fnsize,
3553 unsigned char* view,
3554 section_size_type view_size,
3556 std::string* to) const
3558 // The function starts with a comparison of the stack pointer and a
3559 // field in the TCB. This is followed by a jump.
3562 if (this->match_view(view, view_size, fnoffset, "\x65\x3b\x25", 3)
3565 // We will call __morestack if the carry flag is set after this
3566 // comparison. We turn the comparison into an stc instruction
3568 view[fnoffset] = '\xf9';
3569 this->set_view_to_nop(view, view_size, fnoffset + 1, 6);
3571 // lea NN(%esp),%ecx
3572 // lea NN(%esp),%edx
3573 else if ((this->match_view(view, view_size, fnoffset, "\x8d\x8c\x24", 3)
3574 || this->match_view(view, view_size, fnoffset, "\x8d\x94\x24", 3))
3577 // This is loading an offset from the stack pointer for a
3578 // comparison. The offset is negative, so we decrease the
3579 // offset by the amount of space we need for the stack. This
3580 // means we will avoid calling __morestack if there happens to
3581 // be plenty of space on the stack already.
3582 unsigned char* pval = view + fnoffset + 3;
3583 uint32_t val = elfcpp::Swap_unaligned<32, false>::readval(pval);
3584 val -= parameters->options().split_stack_adjust_size();
3585 elfcpp::Swap_unaligned<32, false>::writeval(pval, val);
3589 if (!object->has_no_split_stack())
3590 object->error(_("failed to match split-stack sequence at "
3591 "section %u offset %0zx"),
3592 shndx, static_cast<size_t>(fnoffset));
3596 // We have to change the function so that it calls
3597 // __morestack_non_split instead of __morestack. The former will
3598 // allocate additional stack space.
3599 *from = "__morestack";
3600 *to = "__morestack_non_split";
3603 // The selector for i386 object files.
3605 class Target_selector_i386 : public Target_selector_freebsd
3608 Target_selector_i386()
3609 : Target_selector_freebsd(elfcpp::EM_386, 32, false,
3610 "elf32-i386", "elf32-i386-freebsd",
3615 do_instantiate_target()
3616 { return new Target_i386(); }
3619 Target_selector_i386 target_selector_i386;
3621 } // End anonymous namespace.