1 // x86_64.cc -- x86_64 target support for gold.
3 // Copyright (C) 2006-2016 Free Software Foundation, Inc.
4 // Written by Ian Lance Taylor <iant@google.com>.
6 // This file is part of gold.
8 // This program is free software; you can redistribute it and/or modify
9 // it under the terms of the GNU General Public License as published by
10 // the Free Software Foundation; either version 3 of the License, or
11 // (at your option) any later version.
13 // This program is distributed in the hope that it will be useful,
14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 // GNU General Public License for more details.
18 // You should have received a copy of the GNU General Public License
19 // along with this program; if not, write to the Free Software
20 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
21 // MA 02110-1301, USA.
29 #include "parameters.h"
36 #include "copy-relocs.h"
38 #include "target-reloc.h"
39 #include "target-select.h"
51 // A class to handle the .got.plt section.
53 class Output_data_got_plt_x86_64 : public Output_section_data_build
56 Output_data_got_plt_x86_64(Layout* layout)
57 : Output_section_data_build(8),
61 Output_data_got_plt_x86_64(Layout* layout, off_t data_size)
62 : Output_section_data_build(data_size, 8),
67 // Write out the PLT data.
69 do_write(Output_file*);
71 // Write to a map file.
73 do_print_to_mapfile(Mapfile* mapfile) const
74 { mapfile->print_output_data(this, "** GOT PLT"); }
77 // A pointer to the Layout class, so that we can find the .dynamic
78 // section when we write out the GOT PLT section.
82 // A class to handle the PLT data.
83 // This is an abstract base class that handles most of the linker details
84 // but does not know the actual contents of PLT entries. The derived
85 // classes below fill in those details.
88 class Output_data_plt_x86_64 : public Output_section_data
91 typedef Output_data_reloc<elfcpp::SHT_RELA, true, size, false> Reloc_section;
93 Output_data_plt_x86_64(Layout* layout, uint64_t addralign,
94 Output_data_got<64, false>* got,
95 Output_data_got_plt_x86_64* got_plt,
96 Output_data_space* got_irelative)
97 : Output_section_data(addralign), tlsdesc_rel_(NULL),
98 irelative_rel_(NULL), got_(got), got_plt_(got_plt),
99 got_irelative_(got_irelative), count_(0), irelative_count_(0),
100 tlsdesc_got_offset_(-1U), free_list_()
101 { this->init(layout); }
103 Output_data_plt_x86_64(Layout* layout, uint64_t plt_entry_size,
104 Output_data_got<64, false>* got,
105 Output_data_got_plt_x86_64* got_plt,
106 Output_data_space* got_irelative,
107 unsigned int plt_count)
108 : Output_section_data((plt_count + 1) * plt_entry_size,
109 plt_entry_size, false),
110 tlsdesc_rel_(NULL), irelative_rel_(NULL), got_(got),
111 got_plt_(got_plt), got_irelative_(got_irelative), count_(plt_count),
112 irelative_count_(0), tlsdesc_got_offset_(-1U), free_list_()
116 // Initialize the free list and reserve the first entry.
117 this->free_list_.init((plt_count + 1) * plt_entry_size, false);
118 this->free_list_.remove(0, plt_entry_size);
121 // Initialize the PLT section.
123 init(Layout* layout);
125 // Add an entry to the PLT.
127 add_entry(Symbol_table*, Layout*, Symbol* gsym);
129 // Add an entry to the PLT for a local STT_GNU_IFUNC symbol.
131 add_local_ifunc_entry(Symbol_table* symtab, Layout*,
132 Sized_relobj_file<size, false>* relobj,
133 unsigned int local_sym_index);
135 // Add the relocation for a PLT entry.
137 add_relocation(Symbol_table*, Layout*, Symbol* gsym,
138 unsigned int got_offset);
140 // Add the reserved TLSDESC_PLT entry to the PLT.
142 reserve_tlsdesc_entry(unsigned int got_offset)
143 { this->tlsdesc_got_offset_ = got_offset; }
145 // Return true if a TLSDESC_PLT entry has been reserved.
147 has_tlsdesc_entry() const
148 { return this->tlsdesc_got_offset_ != -1U; }
150 // Return the GOT offset for the reserved TLSDESC_PLT entry.
152 get_tlsdesc_got_offset() const
153 { return this->tlsdesc_got_offset_; }
155 // Return the offset of the reserved TLSDESC_PLT entry.
157 get_tlsdesc_plt_offset() const
159 return ((this->count_ + this->irelative_count_ + 1)
160 * this->get_plt_entry_size());
163 // Return the .rela.plt section data.
166 { return this->rel_; }
168 // Return where the TLSDESC relocations should go.
170 rela_tlsdesc(Layout*);
172 // Return where the IRELATIVE relocations should go in the PLT
175 rela_irelative(Symbol_table*, Layout*);
177 // Return whether we created a section for IRELATIVE relocations.
179 has_irelative_section() const
180 { return this->irelative_rel_ != NULL; }
182 // Return the number of PLT entries.
185 { return this->count_ + this->irelative_count_; }
187 // Return the offset of the first non-reserved PLT entry.
189 first_plt_entry_offset()
190 { return this->get_plt_entry_size(); }
192 // Return the size of a PLT entry.
194 get_plt_entry_size() const
195 { return this->do_get_plt_entry_size(); }
197 // Reserve a slot in the PLT for an existing symbol in an incremental update.
199 reserve_slot(unsigned int plt_index)
201 this->free_list_.remove((plt_index + 1) * this->get_plt_entry_size(),
202 (plt_index + 2) * this->get_plt_entry_size());
205 // Return the PLT address to use for a global symbol.
207 address_for_global(const Symbol*);
209 // Return the PLT address to use for a local symbol.
211 address_for_local(const Relobj*, unsigned int symndx);
213 // Add .eh_frame information for the PLT.
215 add_eh_frame(Layout* layout)
216 { this->do_add_eh_frame(layout); }
219 // Fill in the first PLT entry.
221 fill_first_plt_entry(unsigned char* pov,
222 typename elfcpp::Elf_types<size>::Elf_Addr got_address,
223 typename elfcpp::Elf_types<size>::Elf_Addr plt_address)
224 { this->do_fill_first_plt_entry(pov, got_address, plt_address); }
226 // Fill in a normal PLT entry. Returns the offset into the entry that
227 // should be the initial GOT slot value.
229 fill_plt_entry(unsigned char* pov,
230 typename elfcpp::Elf_types<size>::Elf_Addr got_address,
231 typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
232 unsigned int got_offset,
233 unsigned int plt_offset,
234 unsigned int plt_index)
236 return this->do_fill_plt_entry(pov, got_address, plt_address,
237 got_offset, plt_offset, plt_index);
240 // Fill in the reserved TLSDESC PLT entry.
242 fill_tlsdesc_entry(unsigned char* pov,
243 typename elfcpp::Elf_types<size>::Elf_Addr got_address,
244 typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
245 typename elfcpp::Elf_types<size>::Elf_Addr got_base,
246 unsigned int tlsdesc_got_offset,
247 unsigned int plt_offset)
249 this->do_fill_tlsdesc_entry(pov, got_address, plt_address, got_base,
250 tlsdesc_got_offset, plt_offset);
254 do_get_plt_entry_size() const = 0;
257 do_fill_first_plt_entry(unsigned char* pov,
258 typename elfcpp::Elf_types<size>::Elf_Addr got_addr,
259 typename elfcpp::Elf_types<size>::Elf_Addr plt_addr)
263 do_fill_plt_entry(unsigned char* pov,
264 typename elfcpp::Elf_types<size>::Elf_Addr got_address,
265 typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
266 unsigned int got_offset,
267 unsigned int plt_offset,
268 unsigned int plt_index) = 0;
271 do_fill_tlsdesc_entry(unsigned char* pov,
272 typename elfcpp::Elf_types<size>::Elf_Addr got_address,
273 typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
274 typename elfcpp::Elf_types<size>::Elf_Addr got_base,
275 unsigned int tlsdesc_got_offset,
276 unsigned int plt_offset) = 0;
279 do_add_eh_frame(Layout* layout) = 0;
282 do_adjust_output_section(Output_section* os);
284 // Write to a map file.
286 do_print_to_mapfile(Mapfile* mapfile) const
287 { mapfile->print_output_data(this, _("** PLT")); }
289 // The CIE of the .eh_frame unwind information for the PLT.
290 static const int plt_eh_frame_cie_size = 16;
291 static const unsigned char plt_eh_frame_cie[plt_eh_frame_cie_size];
294 // Set the final size.
296 set_final_data_size();
298 // Write out the PLT data.
300 do_write(Output_file*);
302 // The reloc section.
304 // The TLSDESC relocs, if necessary. These must follow the regular
306 Reloc_section* tlsdesc_rel_;
307 // The IRELATIVE relocs, if necessary. These must follow the
308 // regular PLT relocations and the TLSDESC relocations.
309 Reloc_section* irelative_rel_;
311 Output_data_got<64, false>* got_;
312 // The .got.plt section.
313 Output_data_got_plt_x86_64* got_plt_;
314 // The part of the .got.plt section used for IRELATIVE relocs.
315 Output_data_space* got_irelative_;
316 // The number of PLT entries.
318 // Number of PLT entries with R_X86_64_IRELATIVE relocs. These
319 // follow the regular PLT entries.
320 unsigned int irelative_count_;
321 // Offset of the reserved TLSDESC_GOT entry when needed.
322 unsigned int tlsdesc_got_offset_;
323 // List of available regions within the section, for incremental
325 Free_list free_list_;
329 class Output_data_plt_x86_64_standard : public Output_data_plt_x86_64<size>
332 Output_data_plt_x86_64_standard(Layout* layout,
333 Output_data_got<64, false>* got,
334 Output_data_got_plt_x86_64* got_plt,
335 Output_data_space* got_irelative)
336 : Output_data_plt_x86_64<size>(layout, plt_entry_size,
337 got, got_plt, got_irelative)
340 Output_data_plt_x86_64_standard(Layout* layout,
341 Output_data_got<64, false>* got,
342 Output_data_got_plt_x86_64* got_plt,
343 Output_data_space* got_irelative,
344 unsigned int plt_count)
345 : Output_data_plt_x86_64<size>(layout, plt_entry_size,
346 got, got_plt, got_irelative,
352 do_get_plt_entry_size() const
353 { return plt_entry_size; }
356 do_add_eh_frame(Layout* layout)
358 layout->add_eh_frame_for_plt(this,
359 this->plt_eh_frame_cie,
360 this->plt_eh_frame_cie_size,
362 plt_eh_frame_fde_size);
366 do_fill_first_plt_entry(unsigned char* pov,
367 typename elfcpp::Elf_types<size>::Elf_Addr got_addr,
368 typename elfcpp::Elf_types<size>::Elf_Addr plt_addr);
371 do_fill_plt_entry(unsigned char* pov,
372 typename elfcpp::Elf_types<size>::Elf_Addr got_address,
373 typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
374 unsigned int got_offset,
375 unsigned int plt_offset,
376 unsigned int plt_index);
379 do_fill_tlsdesc_entry(unsigned char* pov,
380 typename elfcpp::Elf_types<size>::Elf_Addr got_address,
381 typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
382 typename elfcpp::Elf_types<size>::Elf_Addr got_base,
383 unsigned int tlsdesc_got_offset,
384 unsigned int plt_offset);
387 // The size of an entry in the PLT.
388 static const int plt_entry_size = 16;
390 // The first entry in the PLT.
391 // From the AMD64 ABI: "Unlike Intel386 ABI, this ABI uses the same
392 // procedure linkage table for both programs and shared objects."
393 static const unsigned char first_plt_entry[plt_entry_size];
395 // Other entries in the PLT for an executable.
396 static const unsigned char plt_entry[plt_entry_size];
398 // The reserved TLSDESC entry in the PLT for an executable.
399 static const unsigned char tlsdesc_plt_entry[plt_entry_size];
401 // The .eh_frame unwind information for the PLT.
402 static const int plt_eh_frame_fde_size = 32;
403 static const unsigned char plt_eh_frame_fde[plt_eh_frame_fde_size];
410 Lazy_view(Sized_relobj_file<size, false>* object, unsigned int data_shndx)
411 : object_(object), data_shndx_(data_shndx), view_(NULL), view_size_(0)
415 operator[](size_t offset)
417 if (this->view_ == NULL)
418 this->view_ = this->object_->section_contents(this->data_shndx_,
421 if (offset >= this->view_size_)
423 return this->view_[offset];
427 Sized_relobj_file<size, false>* object_;
428 unsigned int data_shndx_;
429 const unsigned char* view_;
430 section_size_type view_size_;
433 // The x86_64 target class.
435 // http://www.x86-64.org/documentation/abi.pdf
436 // TLS info comes from
437 // http://people.redhat.com/drepper/tls.pdf
438 // http://www.lsd.ic.unicamp.br/~oliva/writeups/TLS/RFC-TLSDESC-x86.txt
441 class Target_x86_64 : public Sized_target<size, false>
444 // In the x86_64 ABI (p 68), it says "The AMD64 ABI architectures
445 // uses only Elf64_Rela relocation entries with explicit addends."
446 typedef Output_data_reloc<elfcpp::SHT_RELA, true, size, false> Reloc_section;
448 Target_x86_64(const Target::Target_info* info = &x86_64_info)
449 : Sized_target<size, false>(info),
450 got_(NULL), plt_(NULL), got_plt_(NULL), got_irelative_(NULL),
451 got_tlsdesc_(NULL), global_offset_table_(NULL), rela_dyn_(NULL),
452 rela_irelative_(NULL), copy_relocs_(elfcpp::R_X86_64_COPY),
453 got_mod_index_offset_(-1U), tlsdesc_reloc_info_(),
454 tls_base_symbol_defined_(false)
457 // Hook for a new output section.
459 do_new_output_section(Output_section*) const;
461 // Scan the relocations to look for symbol adjustments.
463 gc_process_relocs(Symbol_table* symtab,
465 Sized_relobj_file<size, false>* object,
466 unsigned int data_shndx,
467 unsigned int sh_type,
468 const unsigned char* prelocs,
470 Output_section* output_section,
471 bool needs_special_offset_handling,
472 size_t local_symbol_count,
473 const unsigned char* plocal_symbols);
475 // Scan the relocations to look for symbol adjustments.
477 scan_relocs(Symbol_table* symtab,
479 Sized_relobj_file<size, false>* object,
480 unsigned int data_shndx,
481 unsigned int sh_type,
482 const unsigned char* prelocs,
484 Output_section* output_section,
485 bool needs_special_offset_handling,
486 size_t local_symbol_count,
487 const unsigned char* plocal_symbols);
489 // Finalize the sections.
491 do_finalize_sections(Layout*, const Input_objects*, Symbol_table*);
493 // Return the value to use for a dynamic which requires special
496 do_dynsym_value(const Symbol*) const;
498 // Relocate a section.
500 relocate_section(const Relocate_info<size, false>*,
501 unsigned int sh_type,
502 const unsigned char* prelocs,
504 Output_section* output_section,
505 bool needs_special_offset_handling,
507 typename elfcpp::Elf_types<size>::Elf_Addr view_address,
508 section_size_type view_size,
509 const Reloc_symbol_changes*);
511 // Scan the relocs during a relocatable link.
513 scan_relocatable_relocs(Symbol_table* symtab,
515 Sized_relobj_file<size, false>* object,
516 unsigned int data_shndx,
517 unsigned int sh_type,
518 const unsigned char* prelocs,
520 Output_section* output_section,
521 bool needs_special_offset_handling,
522 size_t local_symbol_count,
523 const unsigned char* plocal_symbols,
524 Relocatable_relocs*);
526 // Scan the relocs for --emit-relocs.
528 emit_relocs_scan(Symbol_table* symtab,
530 Sized_relobj_file<size, false>* object,
531 unsigned int data_shndx,
532 unsigned int sh_type,
533 const unsigned char* prelocs,
535 Output_section* output_section,
536 bool needs_special_offset_handling,
537 size_t local_symbol_count,
538 const unsigned char* plocal_syms,
539 Relocatable_relocs* rr);
541 // Emit relocations for a section.
544 const Relocate_info<size, false>*,
545 unsigned int sh_type,
546 const unsigned char* prelocs,
548 Output_section* output_section,
549 typename elfcpp::Elf_types<size>::Elf_Off offset_in_output_section,
551 typename elfcpp::Elf_types<size>::Elf_Addr view_address,
552 section_size_type view_size,
553 unsigned char* reloc_view,
554 section_size_type reloc_view_size);
556 // Return a string used to fill a code section with nops.
558 do_code_fill(section_size_type length) const;
560 // Return whether SYM is defined by the ABI.
562 do_is_defined_by_abi(const Symbol* sym) const
563 { return strcmp(sym->name(), "__tls_get_addr") == 0; }
565 // Return the symbol index to use for a target specific relocation.
566 // The only target specific relocation is R_X86_64_TLSDESC for a
567 // local symbol, which is an absolute reloc.
569 do_reloc_symbol_index(void*, unsigned int r_type) const
571 gold_assert(r_type == elfcpp::R_X86_64_TLSDESC);
575 // Return the addend to use for a target specific relocation.
577 do_reloc_addend(void* arg, unsigned int r_type, uint64_t addend) const;
579 // Return the PLT section.
581 do_plt_address_for_global(const Symbol* gsym) const
582 { return this->plt_section()->address_for_global(gsym); }
585 do_plt_address_for_local(const Relobj* relobj, unsigned int symndx) const
586 { return this->plt_section()->address_for_local(relobj, symndx); }
588 // This function should be defined in targets that can use relocation
589 // types to determine (implemented in local_reloc_may_be_function_pointer
590 // and global_reloc_may_be_function_pointer)
591 // if a function's pointer is taken. ICF uses this in safe mode to only
592 // fold those functions whose pointer is defintely not taken. For x86_64
593 // pie binaries, safe ICF cannot be done by looking at relocation types.
595 do_can_check_for_function_pointers() const
596 { return !parameters->options().pie(); }
598 // Return the base for a DW_EH_PE_datarel encoding.
600 do_ehframe_datarel_base() const;
602 // Adjust -fsplit-stack code which calls non-split-stack code.
604 do_calls_non_split(Relobj* object, unsigned int shndx,
605 section_offset_type fnoffset, section_size_type fnsize,
606 const unsigned char* prelocs, size_t reloc_count,
607 unsigned char* view, section_size_type view_size,
608 std::string* from, std::string* to) const;
610 // Return the size of the GOT section.
614 gold_assert(this->got_ != NULL);
615 return this->got_->data_size();
618 // Return the number of entries in the GOT.
620 got_entry_count() const
622 if (this->got_ == NULL)
624 return this->got_size() / 8;
627 // Return the number of entries in the PLT.
629 plt_entry_count() const;
631 // Return the offset of the first non-reserved PLT entry.
633 first_plt_entry_offset() const;
635 // Return the size of each PLT entry.
637 plt_entry_size() const;
639 // Return the size of each GOT entry.
641 got_entry_size() const
644 // Create the GOT section for an incremental update.
645 Output_data_got_base*
646 init_got_plt_for_update(Symbol_table* symtab,
648 unsigned int got_count,
649 unsigned int plt_count);
651 // Reserve a GOT entry for a local symbol, and regenerate any
652 // necessary dynamic relocations.
654 reserve_local_got_entry(unsigned int got_index,
655 Sized_relobj<size, false>* obj,
657 unsigned int got_type);
659 // Reserve a GOT entry for a global symbol, and regenerate any
660 // necessary dynamic relocations.
662 reserve_global_got_entry(unsigned int got_index, Symbol* gsym,
663 unsigned int got_type);
665 // Register an existing PLT entry for a global symbol.
667 register_global_plt_entry(Symbol_table*, Layout*, unsigned int plt_index,
670 // Force a COPY relocation for a given symbol.
672 emit_copy_reloc(Symbol_table*, Symbol*, Output_section*, off_t);
674 // Apply an incremental relocation.
676 apply_relocation(const Relocate_info<size, false>* relinfo,
677 typename elfcpp::Elf_types<size>::Elf_Addr r_offset,
679 typename elfcpp::Elf_types<size>::Elf_Swxword r_addend,
682 typename elfcpp::Elf_types<size>::Elf_Addr address,
683 section_size_type view_size);
685 // Add a new reloc argument, returning the index in the vector.
687 add_tlsdesc_info(Sized_relobj_file<size, false>* object, unsigned int r_sym)
689 this->tlsdesc_reloc_info_.push_back(Tlsdesc_info(object, r_sym));
690 return this->tlsdesc_reloc_info_.size() - 1;
693 Output_data_plt_x86_64<size>*
694 make_data_plt(Layout* layout,
695 Output_data_got<64, false>* got,
696 Output_data_got_plt_x86_64* got_plt,
697 Output_data_space* got_irelative)
699 return this->do_make_data_plt(layout, got, got_plt, got_irelative);
702 Output_data_plt_x86_64<size>*
703 make_data_plt(Layout* layout,
704 Output_data_got<64, false>* got,
705 Output_data_got_plt_x86_64* got_plt,
706 Output_data_space* got_irelative,
707 unsigned int plt_count)
709 return this->do_make_data_plt(layout, got, got_plt, got_irelative,
713 virtual Output_data_plt_x86_64<size>*
714 do_make_data_plt(Layout* layout,
715 Output_data_got<64, false>* got,
716 Output_data_got_plt_x86_64* got_plt,
717 Output_data_space* got_irelative)
719 return new Output_data_plt_x86_64_standard<size>(layout, got, got_plt,
723 virtual Output_data_plt_x86_64<size>*
724 do_make_data_plt(Layout* layout,
725 Output_data_got<64, false>* got,
726 Output_data_got_plt_x86_64* got_plt,
727 Output_data_space* got_irelative,
728 unsigned int plt_count)
730 return new Output_data_plt_x86_64_standard<size>(layout, got, got_plt,
736 // The class which scans relocations.
741 : issued_non_pic_error_(false)
745 get_reference_flags(unsigned int r_type);
748 local(Symbol_table* symtab, Layout* layout, Target_x86_64* target,
749 Sized_relobj_file<size, false>* object,
750 unsigned int data_shndx,
751 Output_section* output_section,
752 const elfcpp::Rela<size, false>& reloc, unsigned int r_type,
753 const elfcpp::Sym<size, false>& lsym,
757 global(Symbol_table* symtab, Layout* layout, Target_x86_64* target,
758 Sized_relobj_file<size, false>* object,
759 unsigned int data_shndx,
760 Output_section* output_section,
761 const elfcpp::Rela<size, false>& reloc, unsigned int r_type,
765 local_reloc_may_be_function_pointer(Symbol_table* symtab, Layout* layout,
766 Target_x86_64* target,
767 Sized_relobj_file<size, false>* object,
768 unsigned int data_shndx,
769 Output_section* output_section,
770 const elfcpp::Rela<size, false>& reloc,
772 const elfcpp::Sym<size, false>& lsym);
775 global_reloc_may_be_function_pointer(Symbol_table* symtab, Layout* layout,
776 Target_x86_64* target,
777 Sized_relobj_file<size, false>* object,
778 unsigned int data_shndx,
779 Output_section* output_section,
780 const elfcpp::Rela<size, false>& reloc,
786 unsupported_reloc_local(Sized_relobj_file<size, false>*,
787 unsigned int r_type);
790 unsupported_reloc_global(Sized_relobj_file<size, false>*,
791 unsigned int r_type, Symbol*);
794 check_non_pic(Relobj*, unsigned int r_type, Symbol*);
797 possible_function_pointer_reloc(unsigned int r_type);
800 reloc_needs_plt_for_ifunc(Sized_relobj_file<size, false>*,
801 unsigned int r_type);
803 // Whether we have issued an error about a non-PIC compilation.
804 bool issued_non_pic_error_;
807 // The class which implements relocation.
812 : skip_call_tls_get_addr_(false)
817 if (this->skip_call_tls_get_addr_)
819 // FIXME: This needs to specify the location somehow.
820 gold_error(_("missing expected TLS relocation"));
824 // Do a relocation. Return false if the caller should not issue
825 // any warnings about this relocation.
827 relocate(const Relocate_info<size, false>*, unsigned int,
828 Target_x86_64*, Output_section*, size_t, const unsigned char*,
829 const Sized_symbol<size>*, const Symbol_value<size>*,
830 unsigned char*, typename elfcpp::Elf_types<size>::Elf_Addr,
834 // Do a TLS relocation.
836 relocate_tls(const Relocate_info<size, false>*, Target_x86_64*,
837 size_t relnum, const elfcpp::Rela<size, false>&,
838 unsigned int r_type, const Sized_symbol<size>*,
839 const Symbol_value<size>*,
840 unsigned char*, typename elfcpp::Elf_types<size>::Elf_Addr,
843 // Do a TLS General-Dynamic to Initial-Exec transition.
845 tls_gd_to_ie(const Relocate_info<size, false>*, size_t relnum,
846 const elfcpp::Rela<size, false>&, unsigned int r_type,
847 typename elfcpp::Elf_types<size>::Elf_Addr value,
849 typename elfcpp::Elf_types<size>::Elf_Addr,
850 section_size_type view_size);
852 // Do a TLS General-Dynamic to Local-Exec transition.
854 tls_gd_to_le(const Relocate_info<size, false>*, size_t relnum,
855 Output_segment* tls_segment,
856 const elfcpp::Rela<size, false>&, unsigned int r_type,
857 typename elfcpp::Elf_types<size>::Elf_Addr value,
859 section_size_type view_size);
861 // Do a TLSDESC-style General-Dynamic to Initial-Exec transition.
863 tls_desc_gd_to_ie(const Relocate_info<size, false>*, size_t relnum,
864 const elfcpp::Rela<size, false>&, unsigned int r_type,
865 typename elfcpp::Elf_types<size>::Elf_Addr value,
867 typename elfcpp::Elf_types<size>::Elf_Addr,
868 section_size_type view_size);
870 // Do a TLSDESC-style General-Dynamic to Local-Exec transition.
872 tls_desc_gd_to_le(const Relocate_info<size, false>*, size_t relnum,
873 Output_segment* tls_segment,
874 const elfcpp::Rela<size, false>&, unsigned int r_type,
875 typename elfcpp::Elf_types<size>::Elf_Addr value,
877 section_size_type view_size);
879 // Do a TLS Local-Dynamic to Local-Exec transition.
881 tls_ld_to_le(const Relocate_info<size, false>*, size_t relnum,
882 Output_segment* tls_segment,
883 const elfcpp::Rela<size, false>&, unsigned int r_type,
884 typename elfcpp::Elf_types<size>::Elf_Addr value,
886 section_size_type view_size);
888 // Do a TLS Initial-Exec to Local-Exec transition.
890 tls_ie_to_le(const Relocate_info<size, false>*, size_t relnum,
891 Output_segment* tls_segment,
892 const elfcpp::Rela<size, false>&, unsigned int r_type,
893 typename elfcpp::Elf_types<size>::Elf_Addr value,
895 section_size_type view_size);
897 // This is set if we should skip the next reloc, which should be a
898 // PLT32 reloc against ___tls_get_addr.
899 bool skip_call_tls_get_addr_;
902 // Check if relocation against this symbol is a candidate for
904 // mov foo@GOTPCREL(%rip), %reg
905 // to lea foo(%rip), %reg.
906 template<class View_type>
908 can_convert_mov_to_lea(const Symbol* gsym, unsigned int r_type,
909 size_t r_offset, View_type* view)
911 gold_assert(gsym != NULL);
912 // We cannot do the conversion unless it's one of these relocations.
913 if (r_type != elfcpp::R_X86_64_GOTPCREL
914 && r_type != elfcpp::R_X86_64_GOTPCRELX
915 && r_type != elfcpp::R_X86_64_REX_GOTPCRELX)
917 // We cannot convert references to IFUNC symbols, or to symbols that
918 // are not local to the current module.
919 if (gsym->type() == elfcpp::STT_GNU_IFUNC
920 || gsym->is_undefined ()
921 || gsym->is_from_dynobj()
922 || gsym->is_preemptible())
924 // If we are building a shared object and the symbol is protected, we may
925 // need to go through the GOT.
926 if (parameters->options().shared()
927 && gsym->visibility() == elfcpp::STV_PROTECTED)
929 // We cannot convert references to the _DYNAMIC symbol.
930 if (strcmp(gsym->name(), "_DYNAMIC") == 0)
932 // Check for a MOV opcode.
933 return (*view)[r_offset - 2] == 0x8b;
937 // callq *foo@GOTPCRELX(%rip) to
939 // and jmpq *foo@GOTPCRELX(%rip) to
942 template<class View_type>
944 can_convert_callq_to_direct(const Symbol* gsym, unsigned int r_type,
945 size_t r_offset, View_type* view)
947 gold_assert(gsym != NULL);
948 // We cannot do the conversion unless it's a GOTPCRELX relocation.
949 if (r_type != elfcpp::R_X86_64_GOTPCRELX)
951 // We cannot convert references to IFUNC symbols, or to symbols that
952 // are not local to the current module.
953 if (gsym->type() == elfcpp::STT_GNU_IFUNC
954 || gsym->is_undefined ()
955 || gsym->is_from_dynobj()
956 || gsym->is_preemptible())
958 // Check for a CALLQ or JMPQ opcode.
959 return ((*view)[r_offset - 2] == 0xff
960 && ((*view)[r_offset - 1] == 0x15
961 || (*view)[r_offset - 1] == 0x25));
964 // Adjust TLS relocation type based on the options and whether this
965 // is a local symbol.
966 static tls::Tls_optimization
967 optimize_tls_reloc(bool is_final, int r_type);
969 // Get the GOT section, creating it if necessary.
970 Output_data_got<64, false>*
971 got_section(Symbol_table*, Layout*);
973 // Get the GOT PLT section.
974 Output_data_got_plt_x86_64*
975 got_plt_section() const
977 gold_assert(this->got_plt_ != NULL);
978 return this->got_plt_;
981 // Get the GOT section for TLSDESC entries.
982 Output_data_got<64, false>*
983 got_tlsdesc_section() const
985 gold_assert(this->got_tlsdesc_ != NULL);
986 return this->got_tlsdesc_;
989 // Create the PLT section.
991 make_plt_section(Symbol_table* symtab, Layout* layout);
993 // Create a PLT entry for a global symbol.
995 make_plt_entry(Symbol_table*, Layout*, Symbol*);
997 // Create a PLT entry for a local STT_GNU_IFUNC symbol.
999 make_local_ifunc_plt_entry(Symbol_table*, Layout*,
1000 Sized_relobj_file<size, false>* relobj,
1001 unsigned int local_sym_index);
1003 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
1005 define_tls_base_symbol(Symbol_table*, Layout*);
1007 // Create the reserved PLT and GOT entries for the TLS descriptor resolver.
1009 reserve_tlsdesc_entries(Symbol_table* symtab, Layout* layout);
1011 // Create a GOT entry for the TLS module index.
1013 got_mod_index_entry(Symbol_table* symtab, Layout* layout,
1014 Sized_relobj_file<size, false>* object);
1016 // Get the PLT section.
1017 Output_data_plt_x86_64<size>*
1020 gold_assert(this->plt_ != NULL);
1024 // Get the dynamic reloc section, creating it if necessary.
1026 rela_dyn_section(Layout*);
1028 // Get the section to use for TLSDESC relocations.
1030 rela_tlsdesc_section(Layout*) const;
1032 // Get the section to use for IRELATIVE relocations.
1034 rela_irelative_section(Layout*);
1036 // Add a potential copy relocation.
1038 copy_reloc(Symbol_table* symtab, Layout* layout,
1039 Sized_relobj_file<size, false>* object,
1040 unsigned int shndx, Output_section* output_section,
1041 Symbol* sym, const elfcpp::Rela<size, false>& reloc)
1043 unsigned int r_type = elfcpp::elf_r_type<size>(reloc.get_r_info());
1044 this->copy_relocs_.copy_reloc(symtab, layout,
1045 symtab->get_sized_symbol<size>(sym),
1046 object, shndx, output_section,
1047 r_type, reloc.get_r_offset(),
1048 reloc.get_r_addend(),
1049 this->rela_dyn_section(layout));
1052 // Information about this specific target which we pass to the
1053 // general Target structure.
1054 static const Target::Target_info x86_64_info;
1056 // The types of GOT entries needed for this platform.
1057 // These values are exposed to the ABI in an incremental link.
1058 // Do not renumber existing values without changing the version
1059 // number of the .gnu_incremental_inputs section.
1062 GOT_TYPE_STANDARD = 0, // GOT entry for a regular symbol
1063 GOT_TYPE_TLS_OFFSET = 1, // GOT entry for TLS offset
1064 GOT_TYPE_TLS_PAIR = 2, // GOT entry for TLS module/offset pair
1065 GOT_TYPE_TLS_DESC = 3 // GOT entry for TLS_DESC pair
1068 // This type is used as the argument to the target specific
1069 // relocation routines. The only target specific reloc is
1070 // R_X86_64_TLSDESC against a local symbol.
1073 Tlsdesc_info(Sized_relobj_file<size, false>* a_object, unsigned int a_r_sym)
1074 : object(a_object), r_sym(a_r_sym)
1077 // The object in which the local symbol is defined.
1078 Sized_relobj_file<size, false>* object;
1079 // The local symbol index in the object.
1084 Output_data_got<64, false>* got_;
1086 Output_data_plt_x86_64<size>* plt_;
1087 // The GOT PLT section.
1088 Output_data_got_plt_x86_64* got_plt_;
1089 // The GOT section for IRELATIVE relocations.
1090 Output_data_space* got_irelative_;
1091 // The GOT section for TLSDESC relocations.
1092 Output_data_got<64, false>* got_tlsdesc_;
1093 // The _GLOBAL_OFFSET_TABLE_ symbol.
1094 Symbol* global_offset_table_;
1095 // The dynamic reloc section.
1096 Reloc_section* rela_dyn_;
1097 // The section to use for IRELATIVE relocs.
1098 Reloc_section* rela_irelative_;
1099 // Relocs saved to avoid a COPY reloc.
1100 Copy_relocs<elfcpp::SHT_RELA, size, false> copy_relocs_;
1101 // Offset of the GOT entry for the TLS module index.
1102 unsigned int got_mod_index_offset_;
1103 // We handle R_X86_64_TLSDESC against a local symbol as a target
1104 // specific relocation. Here we store the object and local symbol
1105 // index for the relocation.
1106 std::vector<Tlsdesc_info> tlsdesc_reloc_info_;
1107 // True if the _TLS_MODULE_BASE_ symbol has been defined.
1108 bool tls_base_symbol_defined_;
1112 const Target::Target_info Target_x86_64<64>::x86_64_info =
1115 false, // is_big_endian
1116 elfcpp::EM_X86_64, // machine_code
1117 false, // has_make_symbol
1118 false, // has_resolve
1119 true, // has_code_fill
1120 true, // is_default_stack_executable
1121 true, // can_icf_inline_merge_sections
1123 "/lib/ld64.so.1", // program interpreter
1124 0x400000, // default_text_segment_address
1125 0x1000, // abi_pagesize (overridable by -z max-page-size)
1126 0x1000, // common_pagesize (overridable by -z common-page-size)
1127 false, // isolate_execinstr
1129 elfcpp::SHN_UNDEF, // small_common_shndx
1130 elfcpp::SHN_X86_64_LCOMMON, // large_common_shndx
1131 0, // small_common_section_flags
1132 elfcpp::SHF_X86_64_LARGE, // large_common_section_flags
1133 NULL, // attributes_section
1134 NULL, // attributes_vendor
1135 "_start", // entry_symbol_name
1136 32, // hash_entry_size
1140 const Target::Target_info Target_x86_64<32>::x86_64_info =
1143 false, // is_big_endian
1144 elfcpp::EM_X86_64, // machine_code
1145 false, // has_make_symbol
1146 false, // has_resolve
1147 true, // has_code_fill
1148 true, // is_default_stack_executable
1149 true, // can_icf_inline_merge_sections
1151 "/libx32/ldx32.so.1", // program interpreter
1152 0x400000, // default_text_segment_address
1153 0x1000, // abi_pagesize (overridable by -z max-page-size)
1154 0x1000, // common_pagesize (overridable by -z common-page-size)
1155 false, // isolate_execinstr
1157 elfcpp::SHN_UNDEF, // small_common_shndx
1158 elfcpp::SHN_X86_64_LCOMMON, // large_common_shndx
1159 0, // small_common_section_flags
1160 elfcpp::SHF_X86_64_LARGE, // large_common_section_flags
1161 NULL, // attributes_section
1162 NULL, // attributes_vendor
1163 "_start", // entry_symbol_name
1164 32, // hash_entry_size
1167 // This is called when a new output section is created. This is where
1168 // we handle the SHF_X86_64_LARGE.
1172 Target_x86_64<size>::do_new_output_section(Output_section* os) const
1174 if ((os->flags() & elfcpp::SHF_X86_64_LARGE) != 0)
1175 os->set_is_large_section();
1178 // Get the GOT section, creating it if necessary.
1181 Output_data_got<64, false>*
1182 Target_x86_64<size>::got_section(Symbol_table* symtab, Layout* layout)
1184 if (this->got_ == NULL)
1186 gold_assert(symtab != NULL && layout != NULL);
1188 // When using -z now, we can treat .got.plt as a relro section.
1189 // Without -z now, it is modified after program startup by lazy
1191 bool is_got_plt_relro = parameters->options().now();
1192 Output_section_order got_order = (is_got_plt_relro
1194 : ORDER_RELRO_LAST);
1195 Output_section_order got_plt_order = (is_got_plt_relro
1197 : ORDER_NON_RELRO_FIRST);
1199 this->got_ = new Output_data_got<64, false>();
1201 layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
1203 | elfcpp::SHF_WRITE),
1204 this->got_, got_order, true);
1206 this->got_plt_ = new Output_data_got_plt_x86_64(layout);
1207 layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
1209 | elfcpp::SHF_WRITE),
1210 this->got_plt_, got_plt_order,
1213 // The first three entries are reserved.
1214 this->got_plt_->set_current_data_size(3 * 8);
1216 if (!is_got_plt_relro)
1218 // Those bytes can go into the relro segment.
1219 layout->increase_relro(3 * 8);
1222 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
1223 this->global_offset_table_ =
1224 symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
1225 Symbol_table::PREDEFINED,
1227 0, 0, elfcpp::STT_OBJECT,
1229 elfcpp::STV_HIDDEN, 0,
1232 // If there are any IRELATIVE relocations, they get GOT entries
1233 // in .got.plt after the jump slot entries.
1234 this->got_irelative_ = new Output_data_space(8, "** GOT IRELATIVE PLT");
1235 layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
1237 | elfcpp::SHF_WRITE),
1238 this->got_irelative_,
1239 got_plt_order, is_got_plt_relro);
1241 // If there are any TLSDESC relocations, they get GOT entries in
1242 // .got.plt after the jump slot and IRELATIVE entries.
1243 this->got_tlsdesc_ = new Output_data_got<64, false>();
1244 layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
1246 | elfcpp::SHF_WRITE),
1248 got_plt_order, is_got_plt_relro);
1254 // Get the dynamic reloc section, creating it if necessary.
1257 typename Target_x86_64<size>::Reloc_section*
1258 Target_x86_64<size>::rela_dyn_section(Layout* layout)
1260 if (this->rela_dyn_ == NULL)
1262 gold_assert(layout != NULL);
1263 this->rela_dyn_ = new Reloc_section(parameters->options().combreloc());
1264 layout->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA,
1265 elfcpp::SHF_ALLOC, this->rela_dyn_,
1266 ORDER_DYNAMIC_RELOCS, false);
1268 return this->rela_dyn_;
1271 // Get the section to use for IRELATIVE relocs, creating it if
1272 // necessary. These go in .rela.dyn, but only after all other dynamic
1273 // relocations. They need to follow the other dynamic relocations so
1274 // that they can refer to global variables initialized by those
1278 typename Target_x86_64<size>::Reloc_section*
1279 Target_x86_64<size>::rela_irelative_section(Layout* layout)
1281 if (this->rela_irelative_ == NULL)
1283 // Make sure we have already created the dynamic reloc section.
1284 this->rela_dyn_section(layout);
1285 this->rela_irelative_ = new Reloc_section(false);
1286 layout->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA,
1287 elfcpp::SHF_ALLOC, this->rela_irelative_,
1288 ORDER_DYNAMIC_RELOCS, false);
1289 gold_assert(this->rela_dyn_->output_section()
1290 == this->rela_irelative_->output_section());
1292 return this->rela_irelative_;
1295 // Write the first three reserved words of the .got.plt section.
1296 // The remainder of the section is written while writing the PLT
1297 // in Output_data_plt_i386::do_write.
1300 Output_data_got_plt_x86_64::do_write(Output_file* of)
1302 // The first entry in the GOT is the address of the .dynamic section
1303 // aka the PT_DYNAMIC segment. The next two entries are reserved.
1304 // We saved space for them when we created the section in
1305 // Target_x86_64::got_section.
1306 const off_t got_file_offset = this->offset();
1307 gold_assert(this->data_size() >= 24);
1308 unsigned char* const got_view = of->get_output_view(got_file_offset, 24);
1309 Output_section* dynamic = this->layout_->dynamic_section();
1310 uint64_t dynamic_addr = dynamic == NULL ? 0 : dynamic->address();
1311 elfcpp::Swap<64, false>::writeval(got_view, dynamic_addr);
1312 memset(got_view + 8, 0, 16);
1313 of->write_output_view(got_file_offset, 24, got_view);
1316 // Initialize the PLT section.
1320 Output_data_plt_x86_64<size>::init(Layout* layout)
1322 this->rel_ = new Reloc_section(false);
1323 layout->add_output_section_data(".rela.plt", elfcpp::SHT_RELA,
1324 elfcpp::SHF_ALLOC, this->rel_,
1325 ORDER_DYNAMIC_PLT_RELOCS, false);
1330 Output_data_plt_x86_64<size>::do_adjust_output_section(Output_section* os)
1332 os->set_entsize(this->get_plt_entry_size());
1335 // Add an entry to the PLT.
1339 Output_data_plt_x86_64<size>::add_entry(Symbol_table* symtab, Layout* layout,
1342 gold_assert(!gsym->has_plt_offset());
1344 unsigned int plt_index;
1346 section_offset_type got_offset;
1348 unsigned int* pcount;
1349 unsigned int offset;
1350 unsigned int reserved;
1351 Output_section_data_build* got;
1352 if (gsym->type() == elfcpp::STT_GNU_IFUNC
1353 && gsym->can_use_relative_reloc(false))
1355 pcount = &this->irelative_count_;
1358 got = this->got_irelative_;
1362 pcount = &this->count_;
1365 got = this->got_plt_;
1368 if (!this->is_data_size_valid())
1370 // Note that when setting the PLT offset for a non-IRELATIVE
1371 // entry we skip the initial reserved PLT entry.
1372 plt_index = *pcount + offset;
1373 plt_offset = plt_index * this->get_plt_entry_size();
1377 got_offset = (plt_index - offset + reserved) * 8;
1378 gold_assert(got_offset == got->current_data_size());
1380 // Every PLT entry needs a GOT entry which points back to the PLT
1381 // entry (this will be changed by the dynamic linker, normally
1382 // lazily when the function is called).
1383 got->set_current_data_size(got_offset + 8);
1387 // FIXME: This is probably not correct for IRELATIVE relocs.
1389 // For incremental updates, find an available slot.
1390 plt_offset = this->free_list_.allocate(this->get_plt_entry_size(),
1391 this->get_plt_entry_size(), 0);
1392 if (plt_offset == -1)
1393 gold_fallback(_("out of patch space (PLT);"
1394 " relink with --incremental-full"));
1396 // The GOT and PLT entries have a 1-1 correspondance, so the GOT offset
1397 // can be calculated from the PLT index, adjusting for the three
1398 // reserved entries at the beginning of the GOT.
1399 plt_index = plt_offset / this->get_plt_entry_size() - 1;
1400 got_offset = (plt_index - offset + reserved) * 8;
1403 gsym->set_plt_offset(plt_offset);
1405 // Every PLT entry needs a reloc.
1406 this->add_relocation(symtab, layout, gsym, got_offset);
1408 // Note that we don't need to save the symbol. The contents of the
1409 // PLT are independent of which symbols are used. The symbols only
1410 // appear in the relocations.
1413 // Add an entry to the PLT for a local STT_GNU_IFUNC symbol. Return
1418 Output_data_plt_x86_64<size>::add_local_ifunc_entry(
1419 Symbol_table* symtab,
1421 Sized_relobj_file<size, false>* relobj,
1422 unsigned int local_sym_index)
1424 unsigned int plt_offset = this->irelative_count_ * this->get_plt_entry_size();
1425 ++this->irelative_count_;
1427 section_offset_type got_offset = this->got_irelative_->current_data_size();
1429 // Every PLT entry needs a GOT entry which points back to the PLT
1431 this->got_irelative_->set_current_data_size(got_offset + 8);
1433 // Every PLT entry needs a reloc.
1434 Reloc_section* rela = this->rela_irelative(symtab, layout);
1435 rela->add_symbolless_local_addend(relobj, local_sym_index,
1436 elfcpp::R_X86_64_IRELATIVE,
1437 this->got_irelative_, got_offset, 0);
1442 // Add the relocation for a PLT entry.
1446 Output_data_plt_x86_64<size>::add_relocation(Symbol_table* symtab,
1449 unsigned int got_offset)
1451 if (gsym->type() == elfcpp::STT_GNU_IFUNC
1452 && gsym->can_use_relative_reloc(false))
1454 Reloc_section* rela = this->rela_irelative(symtab, layout);
1455 rela->add_symbolless_global_addend(gsym, elfcpp::R_X86_64_IRELATIVE,
1456 this->got_irelative_, got_offset, 0);
1460 gsym->set_needs_dynsym_entry();
1461 this->rel_->add_global(gsym, elfcpp::R_X86_64_JUMP_SLOT, this->got_plt_,
1466 // Return where the TLSDESC relocations should go, creating it if
1467 // necessary. These follow the JUMP_SLOT relocations.
1470 typename Output_data_plt_x86_64<size>::Reloc_section*
1471 Output_data_plt_x86_64<size>::rela_tlsdesc(Layout* layout)
1473 if (this->tlsdesc_rel_ == NULL)
1475 this->tlsdesc_rel_ = new Reloc_section(false);
1476 layout->add_output_section_data(".rela.plt", elfcpp::SHT_RELA,
1477 elfcpp::SHF_ALLOC, this->tlsdesc_rel_,
1478 ORDER_DYNAMIC_PLT_RELOCS, false);
1479 gold_assert(this->tlsdesc_rel_->output_section()
1480 == this->rel_->output_section());
1482 return this->tlsdesc_rel_;
1485 // Return where the IRELATIVE relocations should go in the PLT. These
1486 // follow the JUMP_SLOT and the TLSDESC relocations.
1489 typename Output_data_plt_x86_64<size>::Reloc_section*
1490 Output_data_plt_x86_64<size>::rela_irelative(Symbol_table* symtab,
1493 if (this->irelative_rel_ == NULL)
1495 // Make sure we have a place for the TLSDESC relocations, in
1496 // case we see any later on.
1497 this->rela_tlsdesc(layout);
1498 this->irelative_rel_ = new Reloc_section(false);
1499 layout->add_output_section_data(".rela.plt", elfcpp::SHT_RELA,
1500 elfcpp::SHF_ALLOC, this->irelative_rel_,
1501 ORDER_DYNAMIC_PLT_RELOCS, false);
1502 gold_assert(this->irelative_rel_->output_section()
1503 == this->rel_->output_section());
1505 if (parameters->doing_static_link())
1507 // A statically linked executable will only have a .rela.plt
1508 // section to hold R_X86_64_IRELATIVE relocs for
1509 // STT_GNU_IFUNC symbols. The library will use these
1510 // symbols to locate the IRELATIVE relocs at program startup
1512 symtab->define_in_output_data("__rela_iplt_start", NULL,
1513 Symbol_table::PREDEFINED,
1514 this->irelative_rel_, 0, 0,
1515 elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL,
1516 elfcpp::STV_HIDDEN, 0, false, true);
1517 symtab->define_in_output_data("__rela_iplt_end", NULL,
1518 Symbol_table::PREDEFINED,
1519 this->irelative_rel_, 0, 0,
1520 elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL,
1521 elfcpp::STV_HIDDEN, 0, true, true);
1524 return this->irelative_rel_;
1527 // Return the PLT address to use for a global symbol.
1531 Output_data_plt_x86_64<size>::address_for_global(const Symbol* gsym)
1533 uint64_t offset = 0;
1534 if (gsym->type() == elfcpp::STT_GNU_IFUNC
1535 && gsym->can_use_relative_reloc(false))
1536 offset = (this->count_ + 1) * this->get_plt_entry_size();
1537 return this->address() + offset + gsym->plt_offset();
1540 // Return the PLT address to use for a local symbol. These are always
1541 // IRELATIVE relocs.
1545 Output_data_plt_x86_64<size>::address_for_local(const Relobj* object,
1548 return (this->address()
1549 + (this->count_ + 1) * this->get_plt_entry_size()
1550 + object->local_plt_offset(r_sym));
1553 // Set the final size.
1556 Output_data_plt_x86_64<size>::set_final_data_size()
1558 unsigned int count = this->count_ + this->irelative_count_;
1559 if (this->has_tlsdesc_entry())
1561 this->set_data_size((count + 1) * this->get_plt_entry_size());
1564 // The first entry in the PLT for an executable.
1568 Output_data_plt_x86_64_standard<size>::first_plt_entry[plt_entry_size] =
1570 // From AMD64 ABI Draft 0.98, page 76
1571 0xff, 0x35, // pushq contents of memory address
1572 0, 0, 0, 0, // replaced with address of .got + 8
1573 0xff, 0x25, // jmp indirect
1574 0, 0, 0, 0, // replaced with address of .got + 16
1575 0x90, 0x90, 0x90, 0x90 // noop (x4)
1580 Output_data_plt_x86_64_standard<size>::do_fill_first_plt_entry(
1582 typename elfcpp::Elf_types<size>::Elf_Addr got_address,
1583 typename elfcpp::Elf_types<size>::Elf_Addr plt_address)
1585 memcpy(pov, first_plt_entry, plt_entry_size);
1586 // We do a jmp relative to the PC at the end of this instruction.
1587 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
1589 - (plt_address + 6)));
1590 elfcpp::Swap<32, false>::writeval(pov + 8,
1592 - (plt_address + 12)));
1595 // Subsequent entries in the PLT for an executable.
1599 Output_data_plt_x86_64_standard<size>::plt_entry[plt_entry_size] =
1601 // From AMD64 ABI Draft 0.98, page 76
1602 0xff, 0x25, // jmpq indirect
1603 0, 0, 0, 0, // replaced with address of symbol in .got
1604 0x68, // pushq immediate
1605 0, 0, 0, 0, // replaced with offset into relocation table
1606 0xe9, // jmpq relative
1607 0, 0, 0, 0 // replaced with offset to start of .plt
1612 Output_data_plt_x86_64_standard<size>::do_fill_plt_entry(
1614 typename elfcpp::Elf_types<size>::Elf_Addr got_address,
1615 typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
1616 unsigned int got_offset,
1617 unsigned int plt_offset,
1618 unsigned int plt_index)
1620 // Check PC-relative offset overflow in PLT entry.
1621 uint64_t plt_got_pcrel_offset = (got_address + got_offset
1622 - (plt_address + plt_offset + 6));
1623 if (Bits<32>::has_overflow(plt_got_pcrel_offset))
1624 gold_error(_("PC-relative offset overflow in PLT entry %d"),
1627 memcpy(pov, plt_entry, plt_entry_size);
1628 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
1629 plt_got_pcrel_offset);
1631 elfcpp::Swap_unaligned<32, false>::writeval(pov + 7, plt_index);
1632 elfcpp::Swap<32, false>::writeval(pov + 12,
1633 - (plt_offset + plt_entry_size));
1638 // The reserved TLSDESC entry in the PLT for an executable.
1642 Output_data_plt_x86_64_standard<size>::tlsdesc_plt_entry[plt_entry_size] =
1644 // From Alexandre Oliva, "Thread-Local Storage Descriptors for IA32
1645 // and AMD64/EM64T", Version 0.9.4 (2005-10-10).
1646 0xff, 0x35, // pushq x(%rip)
1647 0, 0, 0, 0, // replaced with address of linkmap GOT entry (at PLTGOT + 8)
1648 0xff, 0x25, // jmpq *y(%rip)
1649 0, 0, 0, 0, // replaced with offset of reserved TLSDESC_GOT entry
1656 Output_data_plt_x86_64_standard<size>::do_fill_tlsdesc_entry(
1658 typename elfcpp::Elf_types<size>::Elf_Addr got_address,
1659 typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
1660 typename elfcpp::Elf_types<size>::Elf_Addr got_base,
1661 unsigned int tlsdesc_got_offset,
1662 unsigned int plt_offset)
1664 memcpy(pov, tlsdesc_plt_entry, plt_entry_size);
1665 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
1667 - (plt_address + plt_offset
1669 elfcpp::Swap_unaligned<32, false>::writeval(pov + 8,
1671 + tlsdesc_got_offset
1672 - (plt_address + plt_offset
1676 // The .eh_frame unwind information for the PLT.
1680 Output_data_plt_x86_64<size>::plt_eh_frame_cie[plt_eh_frame_cie_size] =
1683 'z', // Augmentation: augmentation size included.
1684 'R', // Augmentation: FDE encoding included.
1685 '\0', // End of augmentation string.
1686 1, // Code alignment factor.
1687 0x78, // Data alignment factor.
1688 16, // Return address column.
1689 1, // Augmentation size.
1690 (elfcpp::DW_EH_PE_pcrel // FDE encoding.
1691 | elfcpp::DW_EH_PE_sdata4),
1692 elfcpp::DW_CFA_def_cfa, 7, 8, // DW_CFA_def_cfa: r7 (rsp) ofs 8.
1693 elfcpp::DW_CFA_offset + 16, 1,// DW_CFA_offset: r16 (rip) at cfa-8.
1694 elfcpp::DW_CFA_nop, // Align to 16 bytes.
1700 Output_data_plt_x86_64_standard<size>::plt_eh_frame_fde[plt_eh_frame_fde_size] =
1702 0, 0, 0, 0, // Replaced with offset to .plt.
1703 0, 0, 0, 0, // Replaced with size of .plt.
1704 0, // Augmentation size.
1705 elfcpp::DW_CFA_def_cfa_offset, 16, // DW_CFA_def_cfa_offset: 16.
1706 elfcpp::DW_CFA_advance_loc + 6, // Advance 6 to __PLT__ + 6.
1707 elfcpp::DW_CFA_def_cfa_offset, 24, // DW_CFA_def_cfa_offset: 24.
1708 elfcpp::DW_CFA_advance_loc + 10, // Advance 10 to __PLT__ + 16.
1709 elfcpp::DW_CFA_def_cfa_expression, // DW_CFA_def_cfa_expression.
1710 11, // Block length.
1711 elfcpp::DW_OP_breg7, 8, // Push %rsp + 8.
1712 elfcpp::DW_OP_breg16, 0, // Push %rip.
1713 elfcpp::DW_OP_lit15, // Push 0xf.
1714 elfcpp::DW_OP_and, // & (%rip & 0xf).
1715 elfcpp::DW_OP_lit11, // Push 0xb.
1716 elfcpp::DW_OP_ge, // >= ((%rip & 0xf) >= 0xb)
1717 elfcpp::DW_OP_lit3, // Push 3.
1718 elfcpp::DW_OP_shl, // << (((%rip & 0xf) >= 0xb) << 3)
1719 elfcpp::DW_OP_plus, // + ((((%rip&0xf)>=0xb)<<3)+%rsp+8
1720 elfcpp::DW_CFA_nop, // Align to 32 bytes.
1726 // Write out the PLT. This uses the hand-coded instructions above,
1727 // and adjusts them as needed. This is specified by the AMD64 ABI.
1731 Output_data_plt_x86_64<size>::do_write(Output_file* of)
1733 const off_t offset = this->offset();
1734 const section_size_type oview_size =
1735 convert_to_section_size_type(this->data_size());
1736 unsigned char* const oview = of->get_output_view(offset, oview_size);
1738 const off_t got_file_offset = this->got_plt_->offset();
1739 gold_assert(parameters->incremental_update()
1740 || (got_file_offset + this->got_plt_->data_size()
1741 == this->got_irelative_->offset()));
1742 const section_size_type got_size =
1743 convert_to_section_size_type(this->got_plt_->data_size()
1744 + this->got_irelative_->data_size());
1745 unsigned char* const got_view = of->get_output_view(got_file_offset,
1748 unsigned char* pov = oview;
1750 // The base address of the .plt section.
1751 typename elfcpp::Elf_types<size>::Elf_Addr plt_address = this->address();
1752 // The base address of the .got section.
1753 typename elfcpp::Elf_types<size>::Elf_Addr got_base = this->got_->address();
1754 // The base address of the PLT portion of the .got section,
1755 // which is where the GOT pointer will point, and where the
1756 // three reserved GOT entries are located.
1757 typename elfcpp::Elf_types<size>::Elf_Addr got_address
1758 = this->got_plt_->address();
1760 this->fill_first_plt_entry(pov, got_address, plt_address);
1761 pov += this->get_plt_entry_size();
1763 // The first three entries in the GOT are reserved, and are written
1764 // by Output_data_got_plt_x86_64::do_write.
1765 unsigned char* got_pov = got_view + 24;
1767 unsigned int plt_offset = this->get_plt_entry_size();
1768 unsigned int got_offset = 24;
1769 const unsigned int count = this->count_ + this->irelative_count_;
1770 for (unsigned int plt_index = 0;
1773 pov += this->get_plt_entry_size(),
1775 plt_offset += this->get_plt_entry_size(),
1778 // Set and adjust the PLT entry itself.
1779 unsigned int lazy_offset = this->fill_plt_entry(pov,
1780 got_address, plt_address,
1781 got_offset, plt_offset,
1784 // Set the entry in the GOT.
1785 elfcpp::Swap<64, false>::writeval(got_pov,
1786 plt_address + plt_offset + lazy_offset);
1789 if (this->has_tlsdesc_entry())
1791 // Set and adjust the reserved TLSDESC PLT entry.
1792 unsigned int tlsdesc_got_offset = this->get_tlsdesc_got_offset();
1793 this->fill_tlsdesc_entry(pov, got_address, plt_address, got_base,
1794 tlsdesc_got_offset, plt_offset);
1795 pov += this->get_plt_entry_size();
1798 gold_assert(static_cast<section_size_type>(pov - oview) == oview_size);
1799 gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size);
1801 of->write_output_view(offset, oview_size, oview);
1802 of->write_output_view(got_file_offset, got_size, got_view);
1805 // Create the PLT section.
1809 Target_x86_64<size>::make_plt_section(Symbol_table* symtab, Layout* layout)
1811 if (this->plt_ == NULL)
1813 // Create the GOT sections first.
1814 this->got_section(symtab, layout);
1816 this->plt_ = this->make_data_plt(layout, this->got_, this->got_plt_,
1817 this->got_irelative_);
1819 // Add unwind information if requested.
1820 if (parameters->options().ld_generated_unwind_info())
1821 this->plt_->add_eh_frame(layout);
1823 layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
1825 | elfcpp::SHF_EXECINSTR),
1826 this->plt_, ORDER_PLT, false);
1828 // Make the sh_info field of .rela.plt point to .plt.
1829 Output_section* rela_plt_os = this->plt_->rela_plt()->output_section();
1830 rela_plt_os->set_info_section(this->plt_->output_section());
1834 // Return the section for TLSDESC relocations.
1837 typename Target_x86_64<size>::Reloc_section*
1838 Target_x86_64<size>::rela_tlsdesc_section(Layout* layout) const
1840 return this->plt_section()->rela_tlsdesc(layout);
1843 // Create a PLT entry for a global symbol.
1847 Target_x86_64<size>::make_plt_entry(Symbol_table* symtab, Layout* layout,
1850 if (gsym->has_plt_offset())
1853 if (this->plt_ == NULL)
1854 this->make_plt_section(symtab, layout);
1856 this->plt_->add_entry(symtab, layout, gsym);
1859 // Make a PLT entry for a local STT_GNU_IFUNC symbol.
1863 Target_x86_64<size>::make_local_ifunc_plt_entry(
1864 Symbol_table* symtab, Layout* layout,
1865 Sized_relobj_file<size, false>* relobj,
1866 unsigned int local_sym_index)
1868 if (relobj->local_has_plt_offset(local_sym_index))
1870 if (this->plt_ == NULL)
1871 this->make_plt_section(symtab, layout);
1872 unsigned int plt_offset = this->plt_->add_local_ifunc_entry(symtab, layout,
1875 relobj->set_local_plt_offset(local_sym_index, plt_offset);
1878 // Return the number of entries in the PLT.
1882 Target_x86_64<size>::plt_entry_count() const
1884 if (this->plt_ == NULL)
1886 return this->plt_->entry_count();
1889 // Return the offset of the first non-reserved PLT entry.
1893 Target_x86_64<size>::first_plt_entry_offset() const
1895 if (this->plt_ == NULL)
1897 return this->plt_->first_plt_entry_offset();
1900 // Return the size of each PLT entry.
1904 Target_x86_64<size>::plt_entry_size() const
1906 if (this->plt_ == NULL)
1908 return this->plt_->get_plt_entry_size();
1911 // Create the GOT and PLT sections for an incremental update.
1914 Output_data_got_base*
1915 Target_x86_64<size>::init_got_plt_for_update(Symbol_table* symtab,
1917 unsigned int got_count,
1918 unsigned int plt_count)
1920 gold_assert(this->got_ == NULL);
1922 this->got_ = new Output_data_got<64, false>(got_count * 8);
1923 layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
1925 | elfcpp::SHF_WRITE),
1926 this->got_, ORDER_RELRO_LAST,
1929 // Add the three reserved entries.
1930 this->got_plt_ = new Output_data_got_plt_x86_64(layout, (plt_count + 3) * 8);
1931 layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
1933 | elfcpp::SHF_WRITE),
1934 this->got_plt_, ORDER_NON_RELRO_FIRST,
1937 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
1938 this->global_offset_table_ =
1939 symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
1940 Symbol_table::PREDEFINED,
1942 0, 0, elfcpp::STT_OBJECT,
1944 elfcpp::STV_HIDDEN, 0,
1947 // If there are any TLSDESC relocations, they get GOT entries in
1948 // .got.plt after the jump slot entries.
1949 // FIXME: Get the count for TLSDESC entries.
1950 this->got_tlsdesc_ = new Output_data_got<64, false>(0);
1951 layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
1952 elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE,
1954 ORDER_NON_RELRO_FIRST, false);
1956 // If there are any IRELATIVE relocations, they get GOT entries in
1957 // .got.plt after the jump slot and TLSDESC entries.
1958 this->got_irelative_ = new Output_data_space(0, 8, "** GOT IRELATIVE PLT");
1959 layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
1960 elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE,
1961 this->got_irelative_,
1962 ORDER_NON_RELRO_FIRST, false);
1964 // Create the PLT section.
1965 this->plt_ = this->make_data_plt(layout, this->got_,
1967 this->got_irelative_,
1970 // Add unwind information if requested.
1971 if (parameters->options().ld_generated_unwind_info())
1972 this->plt_->add_eh_frame(layout);
1974 layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
1975 elfcpp::SHF_ALLOC | elfcpp::SHF_EXECINSTR,
1976 this->plt_, ORDER_PLT, false);
1978 // Make the sh_info field of .rela.plt point to .plt.
1979 Output_section* rela_plt_os = this->plt_->rela_plt()->output_section();
1980 rela_plt_os->set_info_section(this->plt_->output_section());
1982 // Create the rela_dyn section.
1983 this->rela_dyn_section(layout);
1988 // Reserve a GOT entry for a local symbol, and regenerate any
1989 // necessary dynamic relocations.
1993 Target_x86_64<size>::reserve_local_got_entry(
1994 unsigned int got_index,
1995 Sized_relobj<size, false>* obj,
1997 unsigned int got_type)
1999 unsigned int got_offset = got_index * 8;
2000 Reloc_section* rela_dyn = this->rela_dyn_section(NULL);
2002 this->got_->reserve_local(got_index, obj, r_sym, got_type);
2005 case GOT_TYPE_STANDARD:
2006 if (parameters->options().output_is_position_independent())
2007 rela_dyn->add_local_relative(obj, r_sym, elfcpp::R_X86_64_RELATIVE,
2008 this->got_, got_offset, 0, false);
2010 case GOT_TYPE_TLS_OFFSET:
2011 rela_dyn->add_local(obj, r_sym, elfcpp::R_X86_64_TPOFF64,
2012 this->got_, got_offset, 0);
2014 case GOT_TYPE_TLS_PAIR:
2015 this->got_->reserve_slot(got_index + 1);
2016 rela_dyn->add_local(obj, r_sym, elfcpp::R_X86_64_DTPMOD64,
2017 this->got_, got_offset, 0);
2019 case GOT_TYPE_TLS_DESC:
2020 gold_fatal(_("TLS_DESC not yet supported for incremental linking"));
2021 // this->got_->reserve_slot(got_index + 1);
2022 // rela_dyn->add_target_specific(elfcpp::R_X86_64_TLSDESC, arg,
2023 // this->got_, got_offset, 0);
2030 // Reserve a GOT entry for a global symbol, and regenerate any
2031 // necessary dynamic relocations.
2035 Target_x86_64<size>::reserve_global_got_entry(unsigned int got_index,
2037 unsigned int got_type)
2039 unsigned int got_offset = got_index * 8;
2040 Reloc_section* rela_dyn = this->rela_dyn_section(NULL);
2042 this->got_->reserve_global(got_index, gsym, got_type);
2045 case GOT_TYPE_STANDARD:
2046 if (!gsym->final_value_is_known())
2048 if (gsym->is_from_dynobj()
2049 || gsym->is_undefined()
2050 || gsym->is_preemptible()
2051 || gsym->type() == elfcpp::STT_GNU_IFUNC)
2052 rela_dyn->add_global(gsym, elfcpp::R_X86_64_GLOB_DAT,
2053 this->got_, got_offset, 0);
2055 rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_RELATIVE,
2056 this->got_, got_offset, 0, false);
2059 case GOT_TYPE_TLS_OFFSET:
2060 rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_TPOFF64,
2061 this->got_, got_offset, 0, false);
2063 case GOT_TYPE_TLS_PAIR:
2064 this->got_->reserve_slot(got_index + 1);
2065 rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_DTPMOD64,
2066 this->got_, got_offset, 0, false);
2067 rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_DTPOFF64,
2068 this->got_, got_offset + 8, 0, false);
2070 case GOT_TYPE_TLS_DESC:
2071 this->got_->reserve_slot(got_index + 1);
2072 rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_TLSDESC,
2073 this->got_, got_offset, 0, false);
2080 // Register an existing PLT entry for a global symbol.
2084 Target_x86_64<size>::register_global_plt_entry(Symbol_table* symtab,
2086 unsigned int plt_index,
2089 gold_assert(this->plt_ != NULL);
2090 gold_assert(!gsym->has_plt_offset());
2092 this->plt_->reserve_slot(plt_index);
2094 gsym->set_plt_offset((plt_index + 1) * this->plt_entry_size());
2096 unsigned int got_offset = (plt_index + 3) * 8;
2097 this->plt_->add_relocation(symtab, layout, gsym, got_offset);
2100 // Force a COPY relocation for a given symbol.
2104 Target_x86_64<size>::emit_copy_reloc(
2105 Symbol_table* symtab, Symbol* sym, Output_section* os, off_t offset)
2107 this->copy_relocs_.emit_copy_reloc(symtab,
2108 symtab->get_sized_symbol<size>(sym),
2111 this->rela_dyn_section(NULL));
2114 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
2118 Target_x86_64<size>::define_tls_base_symbol(Symbol_table* symtab,
2121 if (this->tls_base_symbol_defined_)
2124 Output_segment* tls_segment = layout->tls_segment();
2125 if (tls_segment != NULL)
2127 bool is_exec = parameters->options().output_is_executable();
2128 symtab->define_in_output_segment("_TLS_MODULE_BASE_", NULL,
2129 Symbol_table::PREDEFINED,
2133 elfcpp::STV_HIDDEN, 0,
2135 ? Symbol::SEGMENT_END
2136 : Symbol::SEGMENT_START),
2139 this->tls_base_symbol_defined_ = true;
2142 // Create the reserved PLT and GOT entries for the TLS descriptor resolver.
2146 Target_x86_64<size>::reserve_tlsdesc_entries(Symbol_table* symtab,
2149 if (this->plt_ == NULL)
2150 this->make_plt_section(symtab, layout);
2152 if (!this->plt_->has_tlsdesc_entry())
2154 // Allocate the TLSDESC_GOT entry.
2155 Output_data_got<64, false>* got = this->got_section(symtab, layout);
2156 unsigned int got_offset = got->add_constant(0);
2158 // Allocate the TLSDESC_PLT entry.
2159 this->plt_->reserve_tlsdesc_entry(got_offset);
2163 // Create a GOT entry for the TLS module index.
2167 Target_x86_64<size>::got_mod_index_entry(Symbol_table* symtab, Layout* layout,
2168 Sized_relobj_file<size, false>* object)
2170 if (this->got_mod_index_offset_ == -1U)
2172 gold_assert(symtab != NULL && layout != NULL && object != NULL);
2173 Reloc_section* rela_dyn = this->rela_dyn_section(layout);
2174 Output_data_got<64, false>* got = this->got_section(symtab, layout);
2175 unsigned int got_offset = got->add_constant(0);
2176 rela_dyn->add_local(object, 0, elfcpp::R_X86_64_DTPMOD64, got,
2178 got->add_constant(0);
2179 this->got_mod_index_offset_ = got_offset;
2181 return this->got_mod_index_offset_;
2184 // Optimize the TLS relocation type based on what we know about the
2185 // symbol. IS_FINAL is true if the final address of this symbol is
2186 // known at link time.
2189 tls::Tls_optimization
2190 Target_x86_64<size>::optimize_tls_reloc(bool is_final, int r_type)
2192 // If we are generating a shared library, then we can't do anything
2194 if (parameters->options().shared())
2195 return tls::TLSOPT_NONE;
2199 case elfcpp::R_X86_64_TLSGD:
2200 case elfcpp::R_X86_64_GOTPC32_TLSDESC:
2201 case elfcpp::R_X86_64_TLSDESC_CALL:
2202 // These are General-Dynamic which permits fully general TLS
2203 // access. Since we know that we are generating an executable,
2204 // we can convert this to Initial-Exec. If we also know that
2205 // this is a local symbol, we can further switch to Local-Exec.
2207 return tls::TLSOPT_TO_LE;
2208 return tls::TLSOPT_TO_IE;
2210 case elfcpp::R_X86_64_TLSLD:
2211 // This is Local-Dynamic, which refers to a local symbol in the
2212 // dynamic TLS block. Since we know that we generating an
2213 // executable, we can switch to Local-Exec.
2214 return tls::TLSOPT_TO_LE;
2216 case elfcpp::R_X86_64_DTPOFF32:
2217 case elfcpp::R_X86_64_DTPOFF64:
2218 // Another Local-Dynamic reloc.
2219 return tls::TLSOPT_TO_LE;
2221 case elfcpp::R_X86_64_GOTTPOFF:
2222 // These are Initial-Exec relocs which get the thread offset
2223 // from the GOT. If we know that we are linking against the
2224 // local symbol, we can switch to Local-Exec, which links the
2225 // thread offset into the instruction.
2227 return tls::TLSOPT_TO_LE;
2228 return tls::TLSOPT_NONE;
2230 case elfcpp::R_X86_64_TPOFF32:
2231 // When we already have Local-Exec, there is nothing further we
2233 return tls::TLSOPT_NONE;
2240 // Get the Reference_flags for a particular relocation.
2244 Target_x86_64<size>::Scan::get_reference_flags(unsigned int r_type)
2248 case elfcpp::R_X86_64_NONE:
2249 case elfcpp::R_X86_64_GNU_VTINHERIT:
2250 case elfcpp::R_X86_64_GNU_VTENTRY:
2251 case elfcpp::R_X86_64_GOTPC32:
2252 case elfcpp::R_X86_64_GOTPC64:
2253 // No symbol reference.
2256 case elfcpp::R_X86_64_64:
2257 case elfcpp::R_X86_64_32:
2258 case elfcpp::R_X86_64_32S:
2259 case elfcpp::R_X86_64_16:
2260 case elfcpp::R_X86_64_8:
2261 return Symbol::ABSOLUTE_REF;
2263 case elfcpp::R_X86_64_PC64:
2264 case elfcpp::R_X86_64_PC32:
2265 case elfcpp::R_X86_64_PC32_BND:
2266 case elfcpp::R_X86_64_PC16:
2267 case elfcpp::R_X86_64_PC8:
2268 case elfcpp::R_X86_64_GOTOFF64:
2269 return Symbol::RELATIVE_REF;
2271 case elfcpp::R_X86_64_PLT32:
2272 case elfcpp::R_X86_64_PLT32_BND:
2273 case elfcpp::R_X86_64_PLTOFF64:
2274 return Symbol::FUNCTION_CALL | Symbol::RELATIVE_REF;
2276 case elfcpp::R_X86_64_GOT64:
2277 case elfcpp::R_X86_64_GOT32:
2278 case elfcpp::R_X86_64_GOTPCREL64:
2279 case elfcpp::R_X86_64_GOTPCREL:
2280 case elfcpp::R_X86_64_GOTPCRELX:
2281 case elfcpp::R_X86_64_REX_GOTPCRELX:
2282 case elfcpp::R_X86_64_GOTPLT64:
2284 return Symbol::ABSOLUTE_REF;
2286 case elfcpp::R_X86_64_TLSGD: // Global-dynamic
2287 case elfcpp::R_X86_64_GOTPC32_TLSDESC: // Global-dynamic (from ~oliva url)
2288 case elfcpp::R_X86_64_TLSDESC_CALL:
2289 case elfcpp::R_X86_64_TLSLD: // Local-dynamic
2290 case elfcpp::R_X86_64_DTPOFF32:
2291 case elfcpp::R_X86_64_DTPOFF64:
2292 case elfcpp::R_X86_64_GOTTPOFF: // Initial-exec
2293 case elfcpp::R_X86_64_TPOFF32: // Local-exec
2294 return Symbol::TLS_REF;
2296 case elfcpp::R_X86_64_COPY:
2297 case elfcpp::R_X86_64_GLOB_DAT:
2298 case elfcpp::R_X86_64_JUMP_SLOT:
2299 case elfcpp::R_X86_64_RELATIVE:
2300 case elfcpp::R_X86_64_IRELATIVE:
2301 case elfcpp::R_X86_64_TPOFF64:
2302 case elfcpp::R_X86_64_DTPMOD64:
2303 case elfcpp::R_X86_64_TLSDESC:
2304 case elfcpp::R_X86_64_SIZE32:
2305 case elfcpp::R_X86_64_SIZE64:
2307 // Not expected. We will give an error later.
2312 // Report an unsupported relocation against a local symbol.
2316 Target_x86_64<size>::Scan::unsupported_reloc_local(
2317 Sized_relobj_file<size, false>* object,
2318 unsigned int r_type)
2320 gold_error(_("%s: unsupported reloc %u against local symbol"),
2321 object->name().c_str(), r_type);
2324 // We are about to emit a dynamic relocation of type R_TYPE. If the
2325 // dynamic linker does not support it, issue an error. The GNU linker
2326 // only issues a non-PIC error for an allocated read-only section.
2327 // Here we know the section is allocated, but we don't know that it is
2328 // read-only. But we check for all the relocation types which the
2329 // glibc dynamic linker supports, so it seems appropriate to issue an
2330 // error even if the section is not read-only. If GSYM is not NULL,
2331 // it is the symbol the relocation is against; if it is NULL, the
2332 // relocation is against a local symbol.
2336 Target_x86_64<size>::Scan::check_non_pic(Relobj* object, unsigned int r_type,
2341 // These are the relocation types supported by glibc for x86_64
2342 // which should always work.
2343 case elfcpp::R_X86_64_RELATIVE:
2344 case elfcpp::R_X86_64_IRELATIVE:
2345 case elfcpp::R_X86_64_GLOB_DAT:
2346 case elfcpp::R_X86_64_JUMP_SLOT:
2347 case elfcpp::R_X86_64_DTPMOD64:
2348 case elfcpp::R_X86_64_DTPOFF64:
2349 case elfcpp::R_X86_64_TPOFF64:
2350 case elfcpp::R_X86_64_64:
2351 case elfcpp::R_X86_64_COPY:
2354 // glibc supports these reloc types, but they can overflow.
2355 case elfcpp::R_X86_64_PC32:
2356 case elfcpp::R_X86_64_PC32_BND:
2357 // A PC relative reference is OK against a local symbol or if
2358 // the symbol is defined locally.
2360 || (!gsym->is_from_dynobj()
2361 && !gsym->is_undefined()
2362 && !gsym->is_preemptible()))
2365 case elfcpp::R_X86_64_32:
2366 // R_X86_64_32 is OK for x32.
2367 if (size == 32 && r_type == elfcpp::R_X86_64_32)
2369 if (this->issued_non_pic_error_)
2371 gold_assert(parameters->options().output_is_position_independent());
2373 object->error(_("requires dynamic R_X86_64_32 reloc which may "
2374 "overflow at runtime; recompile with -fPIC"));
2380 case elfcpp::R_X86_64_32:
2381 r_name = "R_X86_64_32";
2383 case elfcpp::R_X86_64_PC32:
2384 r_name = "R_X86_64_PC32";
2386 case elfcpp::R_X86_64_PC32_BND:
2387 r_name = "R_X86_64_PC32_BND";
2393 object->error(_("requires dynamic %s reloc against '%s' "
2394 "which may overflow at runtime; recompile "
2396 r_name, gsym->name());
2398 this->issued_non_pic_error_ = true;
2402 // This prevents us from issuing more than one error per reloc
2403 // section. But we can still wind up issuing more than one
2404 // error per object file.
2405 if (this->issued_non_pic_error_)
2407 gold_assert(parameters->options().output_is_position_independent());
2408 object->error(_("requires unsupported dynamic reloc %u; "
2409 "recompile with -fPIC"),
2411 this->issued_non_pic_error_ = true;
2414 case elfcpp::R_X86_64_NONE:
2419 // Return whether we need to make a PLT entry for a relocation of the
2420 // given type against a STT_GNU_IFUNC symbol.
2424 Target_x86_64<size>::Scan::reloc_needs_plt_for_ifunc(
2425 Sized_relobj_file<size, false>* object,
2426 unsigned int r_type)
2428 int flags = Scan::get_reference_flags(r_type);
2429 if (flags & Symbol::TLS_REF)
2430 gold_error(_("%s: unsupported TLS reloc %u for IFUNC symbol"),
2431 object->name().c_str(), r_type);
2435 // Scan a relocation for a local symbol.
2439 Target_x86_64<size>::Scan::local(Symbol_table* symtab,
2441 Target_x86_64<size>* target,
2442 Sized_relobj_file<size, false>* object,
2443 unsigned int data_shndx,
2444 Output_section* output_section,
2445 const elfcpp::Rela<size, false>& reloc,
2446 unsigned int r_type,
2447 const elfcpp::Sym<size, false>& lsym,
2453 // A local STT_GNU_IFUNC symbol may require a PLT entry.
2454 bool is_ifunc = lsym.get_st_type() == elfcpp::STT_GNU_IFUNC;
2455 if (is_ifunc && this->reloc_needs_plt_for_ifunc(object, r_type))
2457 unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2458 target->make_local_ifunc_plt_entry(symtab, layout, object, r_sym);
2463 case elfcpp::R_X86_64_NONE:
2464 case elfcpp::R_X86_64_GNU_VTINHERIT:
2465 case elfcpp::R_X86_64_GNU_VTENTRY:
2468 case elfcpp::R_X86_64_64:
2469 // If building a shared library (or a position-independent
2470 // executable), we need to create a dynamic relocation for this
2471 // location. The relocation applied at link time will apply the
2472 // link-time value, so we flag the location with an
2473 // R_X86_64_RELATIVE relocation so the dynamic loader can
2474 // relocate it easily.
2475 if (parameters->options().output_is_position_independent())
2477 unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2478 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2479 rela_dyn->add_local_relative(object, r_sym,
2481 ? elfcpp::R_X86_64_RELATIVE64
2482 : elfcpp::R_X86_64_RELATIVE),
2483 output_section, data_shndx,
2484 reloc.get_r_offset(),
2485 reloc.get_r_addend(), is_ifunc);
2489 case elfcpp::R_X86_64_32:
2490 case elfcpp::R_X86_64_32S:
2491 case elfcpp::R_X86_64_16:
2492 case elfcpp::R_X86_64_8:
2493 // If building a shared library (or a position-independent
2494 // executable), we need to create a dynamic relocation for this
2495 // location. We can't use an R_X86_64_RELATIVE relocation
2496 // because that is always a 64-bit relocation.
2497 if (parameters->options().output_is_position_independent())
2499 // Use R_X86_64_RELATIVE relocation for R_X86_64_32 under x32.
2500 if (size == 32 && r_type == elfcpp::R_X86_64_32)
2502 unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2503 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2504 rela_dyn->add_local_relative(object, r_sym,
2505 elfcpp::R_X86_64_RELATIVE,
2506 output_section, data_shndx,
2507 reloc.get_r_offset(),
2508 reloc.get_r_addend(), is_ifunc);
2512 this->check_non_pic(object, r_type, NULL);
2514 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2515 unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2516 if (lsym.get_st_type() != elfcpp::STT_SECTION)
2517 rela_dyn->add_local(object, r_sym, r_type, output_section,
2518 data_shndx, reloc.get_r_offset(),
2519 reloc.get_r_addend());
2522 gold_assert(lsym.get_st_value() == 0);
2523 unsigned int shndx = lsym.get_st_shndx();
2525 shndx = object->adjust_sym_shndx(r_sym, shndx,
2528 object->error(_("section symbol %u has bad shndx %u"),
2531 rela_dyn->add_local_section(object, shndx,
2532 r_type, output_section,
2533 data_shndx, reloc.get_r_offset(),
2534 reloc.get_r_addend());
2539 case elfcpp::R_X86_64_PC64:
2540 case elfcpp::R_X86_64_PC32:
2541 case elfcpp::R_X86_64_PC32_BND:
2542 case elfcpp::R_X86_64_PC16:
2543 case elfcpp::R_X86_64_PC8:
2546 case elfcpp::R_X86_64_PLT32:
2547 case elfcpp::R_X86_64_PLT32_BND:
2548 // Since we know this is a local symbol, we can handle this as a
2552 case elfcpp::R_X86_64_GOTPC32:
2553 case elfcpp::R_X86_64_GOTOFF64:
2554 case elfcpp::R_X86_64_GOTPC64:
2555 case elfcpp::R_X86_64_PLTOFF64:
2556 // We need a GOT section.
2557 target->got_section(symtab, layout);
2558 // For PLTOFF64, we'd normally want a PLT section, but since we
2559 // know this is a local symbol, no PLT is needed.
2562 case elfcpp::R_X86_64_GOT64:
2563 case elfcpp::R_X86_64_GOT32:
2564 case elfcpp::R_X86_64_GOTPCREL64:
2565 case elfcpp::R_X86_64_GOTPCREL:
2566 case elfcpp::R_X86_64_GOTPCRELX:
2567 case elfcpp::R_X86_64_REX_GOTPCRELX:
2568 case elfcpp::R_X86_64_GOTPLT64:
2570 // The symbol requires a GOT section.
2571 Output_data_got<64, false>* got = target->got_section(symtab, layout);
2573 // If the relocation symbol isn't IFUNC,
2574 // and is local, then we will convert
2575 // mov foo@GOTPCREL(%rip), %reg
2576 // to lea foo(%rip), %reg.
2577 // in Relocate::relocate.
2578 if ((r_type == elfcpp::R_X86_64_GOTPCREL
2579 || r_type == elfcpp::R_X86_64_GOTPCRELX
2580 || r_type == elfcpp::R_X86_64_REX_GOTPCRELX)
2581 && reloc.get_r_offset() >= 2
2584 section_size_type stype;
2585 const unsigned char* view = object->section_contents(data_shndx,
2587 if (view[reloc.get_r_offset() - 2] == 0x8b)
2592 // The symbol requires a GOT entry.
2593 unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2595 // For a STT_GNU_IFUNC symbol we want the PLT offset. That
2596 // lets function pointers compare correctly with shared
2597 // libraries. Otherwise we would need an IRELATIVE reloc.
2600 is_new = got->add_local_plt(object, r_sym, GOT_TYPE_STANDARD);
2602 is_new = got->add_local(object, r_sym, GOT_TYPE_STANDARD);
2605 // If we are generating a shared object, we need to add a
2606 // dynamic relocation for this symbol's GOT entry.
2607 if (parameters->options().output_is_position_independent())
2609 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2610 // R_X86_64_RELATIVE assumes a 64-bit relocation.
2611 if (r_type != elfcpp::R_X86_64_GOT32)
2613 unsigned int got_offset =
2614 object->local_got_offset(r_sym, GOT_TYPE_STANDARD);
2615 rela_dyn->add_local_relative(object, r_sym,
2616 elfcpp::R_X86_64_RELATIVE,
2617 got, got_offset, 0, is_ifunc);
2621 this->check_non_pic(object, r_type, NULL);
2623 gold_assert(lsym.get_st_type() != elfcpp::STT_SECTION);
2624 rela_dyn->add_local(
2625 object, r_sym, r_type, got,
2626 object->local_got_offset(r_sym, GOT_TYPE_STANDARD), 0);
2630 // For GOTPLT64, we'd normally want a PLT section, but since
2631 // we know this is a local symbol, no PLT is needed.
2635 case elfcpp::R_X86_64_COPY:
2636 case elfcpp::R_X86_64_GLOB_DAT:
2637 case elfcpp::R_X86_64_JUMP_SLOT:
2638 case elfcpp::R_X86_64_RELATIVE:
2639 case elfcpp::R_X86_64_IRELATIVE:
2640 // These are outstanding tls relocs, which are unexpected when linking
2641 case elfcpp::R_X86_64_TPOFF64:
2642 case elfcpp::R_X86_64_DTPMOD64:
2643 case elfcpp::R_X86_64_TLSDESC:
2644 gold_error(_("%s: unexpected reloc %u in object file"),
2645 object->name().c_str(), r_type);
2648 // These are initial tls relocs, which are expected when linking
2649 case elfcpp::R_X86_64_TLSGD: // Global-dynamic
2650 case elfcpp::R_X86_64_GOTPC32_TLSDESC: // Global-dynamic (from ~oliva url)
2651 case elfcpp::R_X86_64_TLSDESC_CALL:
2652 case elfcpp::R_X86_64_TLSLD: // Local-dynamic
2653 case elfcpp::R_X86_64_DTPOFF32:
2654 case elfcpp::R_X86_64_DTPOFF64:
2655 case elfcpp::R_X86_64_GOTTPOFF: // Initial-exec
2656 case elfcpp::R_X86_64_TPOFF32: // Local-exec
2658 bool output_is_shared = parameters->options().shared();
2659 const tls::Tls_optimization optimized_type
2660 = Target_x86_64<size>::optimize_tls_reloc(!output_is_shared,
2664 case elfcpp::R_X86_64_TLSGD: // General-dynamic
2665 if (optimized_type == tls::TLSOPT_NONE)
2667 // Create a pair of GOT entries for the module index and
2668 // dtv-relative offset.
2669 Output_data_got<64, false>* got
2670 = target->got_section(symtab, layout);
2671 unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2672 unsigned int shndx = lsym.get_st_shndx();
2674 shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
2676 object->error(_("local symbol %u has bad shndx %u"),
2679 got->add_local_pair_with_rel(object, r_sym,
2682 target->rela_dyn_section(layout),
2683 elfcpp::R_X86_64_DTPMOD64);
2685 else if (optimized_type != tls::TLSOPT_TO_LE)
2686 unsupported_reloc_local(object, r_type);
2689 case elfcpp::R_X86_64_GOTPC32_TLSDESC:
2690 target->define_tls_base_symbol(symtab, layout);
2691 if (optimized_type == tls::TLSOPT_NONE)
2693 // Create reserved PLT and GOT entries for the resolver.
2694 target->reserve_tlsdesc_entries(symtab, layout);
2696 // Generate a double GOT entry with an
2697 // R_X86_64_TLSDESC reloc. The R_X86_64_TLSDESC reloc
2698 // is resolved lazily, so the GOT entry needs to be in
2699 // an area in .got.plt, not .got. Call got_section to
2700 // make sure the section has been created.
2701 target->got_section(symtab, layout);
2702 Output_data_got<64, false>* got = target->got_tlsdesc_section();
2703 unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2704 if (!object->local_has_got_offset(r_sym, GOT_TYPE_TLS_DESC))
2706 unsigned int got_offset = got->add_constant(0);
2707 got->add_constant(0);
2708 object->set_local_got_offset(r_sym, GOT_TYPE_TLS_DESC,
2710 Reloc_section* rt = target->rela_tlsdesc_section(layout);
2711 // We store the arguments we need in a vector, and
2712 // use the index into the vector as the parameter
2713 // to pass to the target specific routines.
2714 uintptr_t intarg = target->add_tlsdesc_info(object, r_sym);
2715 void* arg = reinterpret_cast<void*>(intarg);
2716 rt->add_target_specific(elfcpp::R_X86_64_TLSDESC, arg,
2717 got, got_offset, 0);
2720 else if (optimized_type != tls::TLSOPT_TO_LE)
2721 unsupported_reloc_local(object, r_type);
2724 case elfcpp::R_X86_64_TLSDESC_CALL:
2727 case elfcpp::R_X86_64_TLSLD: // Local-dynamic
2728 if (optimized_type == tls::TLSOPT_NONE)
2730 // Create a GOT entry for the module index.
2731 target->got_mod_index_entry(symtab, layout, object);
2733 else if (optimized_type != tls::TLSOPT_TO_LE)
2734 unsupported_reloc_local(object, r_type);
2737 case elfcpp::R_X86_64_DTPOFF32:
2738 case elfcpp::R_X86_64_DTPOFF64:
2741 case elfcpp::R_X86_64_GOTTPOFF: // Initial-exec
2742 layout->set_has_static_tls();
2743 if (optimized_type == tls::TLSOPT_NONE)
2745 // Create a GOT entry for the tp-relative offset.
2746 Output_data_got<64, false>* got
2747 = target->got_section(symtab, layout);
2748 unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2749 got->add_local_with_rel(object, r_sym, GOT_TYPE_TLS_OFFSET,
2750 target->rela_dyn_section(layout),
2751 elfcpp::R_X86_64_TPOFF64);
2753 else if (optimized_type != tls::TLSOPT_TO_LE)
2754 unsupported_reloc_local(object, r_type);
2757 case elfcpp::R_X86_64_TPOFF32: // Local-exec
2758 layout->set_has_static_tls();
2759 if (output_is_shared)
2760 unsupported_reloc_local(object, r_type);
2769 case elfcpp::R_X86_64_SIZE32:
2770 case elfcpp::R_X86_64_SIZE64:
2772 gold_error(_("%s: unsupported reloc %u against local symbol"),
2773 object->name().c_str(), r_type);
2779 // Report an unsupported relocation against a global symbol.
2783 Target_x86_64<size>::Scan::unsupported_reloc_global(
2784 Sized_relobj_file<size, false>* object,
2785 unsigned int r_type,
2788 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
2789 object->name().c_str(), r_type, gsym->demangled_name().c_str());
2792 // Returns true if this relocation type could be that of a function pointer.
2795 Target_x86_64<size>::Scan::possible_function_pointer_reloc(unsigned int r_type)
2799 case elfcpp::R_X86_64_64:
2800 case elfcpp::R_X86_64_32:
2801 case elfcpp::R_X86_64_32S:
2802 case elfcpp::R_X86_64_16:
2803 case elfcpp::R_X86_64_8:
2804 case elfcpp::R_X86_64_GOT64:
2805 case elfcpp::R_X86_64_GOT32:
2806 case elfcpp::R_X86_64_GOTPCREL64:
2807 case elfcpp::R_X86_64_GOTPCREL:
2808 case elfcpp::R_X86_64_GOTPCRELX:
2809 case elfcpp::R_X86_64_REX_GOTPCRELX:
2810 case elfcpp::R_X86_64_GOTPLT64:
2818 // For safe ICF, scan a relocation for a local symbol to check if it
2819 // corresponds to a function pointer being taken. In that case mark
2820 // the function whose pointer was taken as not foldable.
2824 Target_x86_64<size>::Scan::local_reloc_may_be_function_pointer(
2827 Target_x86_64<size>* ,
2828 Sized_relobj_file<size, false>* ,
2831 const elfcpp::Rela<size, false>& ,
2832 unsigned int r_type,
2833 const elfcpp::Sym<size, false>&)
2835 // When building a shared library, do not fold any local symbols as it is
2836 // not possible to distinguish pointer taken versus a call by looking at
2837 // the relocation types.
2838 return (parameters->options().shared()
2839 || possible_function_pointer_reloc(r_type));
2842 // For safe ICF, scan a relocation for a global symbol to check if it
2843 // corresponds to a function pointer being taken. In that case mark
2844 // the function whose pointer was taken as not foldable.
2848 Target_x86_64<size>::Scan::global_reloc_may_be_function_pointer(
2851 Target_x86_64<size>* ,
2852 Sized_relobj_file<size, false>* ,
2855 const elfcpp::Rela<size, false>& ,
2856 unsigned int r_type,
2859 // When building a shared library, do not fold symbols whose visibility
2860 // is hidden, internal or protected.
2861 return ((parameters->options().shared()
2862 && (gsym->visibility() == elfcpp::STV_INTERNAL
2863 || gsym->visibility() == elfcpp::STV_PROTECTED
2864 || gsym->visibility() == elfcpp::STV_HIDDEN))
2865 || possible_function_pointer_reloc(r_type));
2868 // Scan a relocation for a global symbol.
2872 Target_x86_64<size>::Scan::global(Symbol_table* symtab,
2874 Target_x86_64<size>* target,
2875 Sized_relobj_file<size, false>* object,
2876 unsigned int data_shndx,
2877 Output_section* output_section,
2878 const elfcpp::Rela<size, false>& reloc,
2879 unsigned int r_type,
2882 // A STT_GNU_IFUNC symbol may require a PLT entry.
2883 if (gsym->type() == elfcpp::STT_GNU_IFUNC
2884 && this->reloc_needs_plt_for_ifunc(object, r_type))
2885 target->make_plt_entry(symtab, layout, gsym);
2889 case elfcpp::R_X86_64_NONE:
2890 case elfcpp::R_X86_64_GNU_VTINHERIT:
2891 case elfcpp::R_X86_64_GNU_VTENTRY:
2894 case elfcpp::R_X86_64_64:
2895 case elfcpp::R_X86_64_32:
2896 case elfcpp::R_X86_64_32S:
2897 case elfcpp::R_X86_64_16:
2898 case elfcpp::R_X86_64_8:
2900 // Make a PLT entry if necessary.
2901 if (gsym->needs_plt_entry())
2903 target->make_plt_entry(symtab, layout, gsym);
2904 // Since this is not a PC-relative relocation, we may be
2905 // taking the address of a function. In that case we need to
2906 // set the entry in the dynamic symbol table to the address of
2908 if (gsym->is_from_dynobj() && !parameters->options().shared())
2909 gsym->set_needs_dynsym_value();
2911 // Make a dynamic relocation if necessary.
2912 if (gsym->needs_dynamic_reloc(Scan::get_reference_flags(r_type)))
2914 if (!parameters->options().output_is_position_independent()
2915 && gsym->may_need_copy_reloc())
2917 target->copy_reloc(symtab, layout, object,
2918 data_shndx, output_section, gsym, reloc);
2920 else if (((size == 64 && r_type == elfcpp::R_X86_64_64)
2921 || (size == 32 && r_type == elfcpp::R_X86_64_32))
2922 && gsym->type() == elfcpp::STT_GNU_IFUNC
2923 && gsym->can_use_relative_reloc(false)
2924 && !gsym->is_from_dynobj()
2925 && !gsym->is_undefined()
2926 && !gsym->is_preemptible())
2928 // Use an IRELATIVE reloc for a locally defined
2929 // STT_GNU_IFUNC symbol. This makes a function
2930 // address in a PIE executable match the address in a
2931 // shared library that it links against.
2932 Reloc_section* rela_dyn =
2933 target->rela_irelative_section(layout);
2934 unsigned int r_type = elfcpp::R_X86_64_IRELATIVE;
2935 rela_dyn->add_symbolless_global_addend(gsym, r_type,
2936 output_section, object,
2938 reloc.get_r_offset(),
2939 reloc.get_r_addend());
2941 else if (((size == 64 && r_type == elfcpp::R_X86_64_64)
2942 || (size == 32 && r_type == elfcpp::R_X86_64_32))
2943 && gsym->can_use_relative_reloc(false))
2945 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2946 rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_RELATIVE,
2947 output_section, object,
2949 reloc.get_r_offset(),
2950 reloc.get_r_addend(), false);
2954 this->check_non_pic(object, r_type, gsym);
2955 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2956 rela_dyn->add_global(gsym, r_type, output_section, object,
2957 data_shndx, reloc.get_r_offset(),
2958 reloc.get_r_addend());
2964 case elfcpp::R_X86_64_PC64:
2965 case elfcpp::R_X86_64_PC32:
2966 case elfcpp::R_X86_64_PC32_BND:
2967 case elfcpp::R_X86_64_PC16:
2968 case elfcpp::R_X86_64_PC8:
2970 // Make a PLT entry if necessary.
2971 if (gsym->needs_plt_entry())
2972 target->make_plt_entry(symtab, layout, gsym);
2973 // Make a dynamic relocation if necessary.
2974 if (gsym->needs_dynamic_reloc(Scan::get_reference_flags(r_type)))
2976 if (parameters->options().output_is_executable()
2977 && gsym->may_need_copy_reloc())
2979 target->copy_reloc(symtab, layout, object,
2980 data_shndx, output_section, gsym, reloc);
2984 this->check_non_pic(object, r_type, gsym);
2985 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2986 rela_dyn->add_global(gsym, r_type, output_section, object,
2987 data_shndx, reloc.get_r_offset(),
2988 reloc.get_r_addend());
2994 case elfcpp::R_X86_64_GOT64:
2995 case elfcpp::R_X86_64_GOT32:
2996 case elfcpp::R_X86_64_GOTPCREL64:
2997 case elfcpp::R_X86_64_GOTPCREL:
2998 case elfcpp::R_X86_64_GOTPCRELX:
2999 case elfcpp::R_X86_64_REX_GOTPCRELX:
3000 case elfcpp::R_X86_64_GOTPLT64:
3002 // The symbol requires a GOT entry.
3003 Output_data_got<64, false>* got = target->got_section(symtab, layout);
3005 // If we convert this from
3006 // mov foo@GOTPCREL(%rip), %reg
3007 // to lea foo(%rip), %reg.
3010 // (callq|jmpq) *foo@GOTPCRELX(%rip) to
3012 // in Relocate::relocate, then there is nothing to do here.
3014 Lazy_view<size> view(object, data_shndx);
3015 size_t r_offset = reloc.get_r_offset();
3017 && Target_x86_64<size>::can_convert_mov_to_lea(gsym, r_type,
3022 && Target_x86_64<size>::can_convert_callq_to_direct(gsym, r_type,
3027 if (gsym->final_value_is_known())
3029 // For a STT_GNU_IFUNC symbol we want the PLT address.
3030 if (gsym->type() == elfcpp::STT_GNU_IFUNC)
3031 got->add_global_plt(gsym, GOT_TYPE_STANDARD);
3033 got->add_global(gsym, GOT_TYPE_STANDARD);
3037 // If this symbol is not fully resolved, we need to add a
3038 // dynamic relocation for it.
3039 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
3041 // Use a GLOB_DAT rather than a RELATIVE reloc if:
3043 // 1) The symbol may be defined in some other module.
3045 // 2) We are building a shared library and this is a
3046 // protected symbol; using GLOB_DAT means that the dynamic
3047 // linker can use the address of the PLT in the main
3048 // executable when appropriate so that function address
3049 // comparisons work.
3051 // 3) This is a STT_GNU_IFUNC symbol in position dependent
3052 // code, again so that function address comparisons work.
3053 if (gsym->is_from_dynobj()
3054 || gsym->is_undefined()
3055 || gsym->is_preemptible()
3056 || (gsym->visibility() == elfcpp::STV_PROTECTED
3057 && parameters->options().shared())
3058 || (gsym->type() == elfcpp::STT_GNU_IFUNC
3059 && parameters->options().output_is_position_independent()))
3060 got->add_global_with_rel(gsym, GOT_TYPE_STANDARD, rela_dyn,
3061 elfcpp::R_X86_64_GLOB_DAT);
3064 // For a STT_GNU_IFUNC symbol we want to write the PLT
3065 // offset into the GOT, so that function pointer
3066 // comparisons work correctly.
3068 if (gsym->type() != elfcpp::STT_GNU_IFUNC)
3069 is_new = got->add_global(gsym, GOT_TYPE_STANDARD);
3072 is_new = got->add_global_plt(gsym, GOT_TYPE_STANDARD);
3073 // Tell the dynamic linker to use the PLT address
3074 // when resolving relocations.
3075 if (gsym->is_from_dynobj()
3076 && !parameters->options().shared())
3077 gsym->set_needs_dynsym_value();
3081 unsigned int got_off = gsym->got_offset(GOT_TYPE_STANDARD);
3082 rela_dyn->add_global_relative(gsym,
3083 elfcpp::R_X86_64_RELATIVE,
3084 got, got_off, 0, false);
3091 case elfcpp::R_X86_64_PLT32:
3092 case elfcpp::R_X86_64_PLT32_BND:
3093 // If the symbol is fully resolved, this is just a PC32 reloc.
3094 // Otherwise we need a PLT entry.
3095 if (gsym->final_value_is_known())
3097 // If building a shared library, we can also skip the PLT entry
3098 // if the symbol is defined in the output file and is protected
3100 if (gsym->is_defined()
3101 && !gsym->is_from_dynobj()
3102 && !gsym->is_preemptible())
3104 target->make_plt_entry(symtab, layout, gsym);
3107 case elfcpp::R_X86_64_GOTPC32:
3108 case elfcpp::R_X86_64_GOTOFF64:
3109 case elfcpp::R_X86_64_GOTPC64:
3110 case elfcpp::R_X86_64_PLTOFF64:
3111 // We need a GOT section.
3112 target->got_section(symtab, layout);
3113 // For PLTOFF64, we also need a PLT entry (but only if the
3114 // symbol is not fully resolved).
3115 if (r_type == elfcpp::R_X86_64_PLTOFF64
3116 && !gsym->final_value_is_known())
3117 target->make_plt_entry(symtab, layout, gsym);
3120 case elfcpp::R_X86_64_COPY:
3121 case elfcpp::R_X86_64_GLOB_DAT:
3122 case elfcpp::R_X86_64_JUMP_SLOT:
3123 case elfcpp::R_X86_64_RELATIVE:
3124 case elfcpp::R_X86_64_IRELATIVE:
3125 // These are outstanding tls relocs, which are unexpected when linking
3126 case elfcpp::R_X86_64_TPOFF64:
3127 case elfcpp::R_X86_64_DTPMOD64:
3128 case elfcpp::R_X86_64_TLSDESC:
3129 gold_error(_("%s: unexpected reloc %u in object file"),
3130 object->name().c_str(), r_type);
3133 // These are initial tls relocs, which are expected for global()
3134 case elfcpp::R_X86_64_TLSGD: // Global-dynamic
3135 case elfcpp::R_X86_64_GOTPC32_TLSDESC: // Global-dynamic (from ~oliva url)
3136 case elfcpp::R_X86_64_TLSDESC_CALL:
3137 case elfcpp::R_X86_64_TLSLD: // Local-dynamic
3138 case elfcpp::R_X86_64_DTPOFF32:
3139 case elfcpp::R_X86_64_DTPOFF64:
3140 case elfcpp::R_X86_64_GOTTPOFF: // Initial-exec
3141 case elfcpp::R_X86_64_TPOFF32: // Local-exec
3143 // For the Initial-Exec model, we can treat undef symbols as final
3144 // when building an executable.
3145 const bool is_final = (gsym->final_value_is_known() ||
3146 (r_type == elfcpp::R_X86_64_GOTTPOFF &&
3147 gsym->is_undefined() &&
3148 parameters->options().output_is_executable()));
3149 const tls::Tls_optimization optimized_type
3150 = Target_x86_64<size>::optimize_tls_reloc(is_final, r_type);
3153 case elfcpp::R_X86_64_TLSGD: // General-dynamic
3154 if (optimized_type == tls::TLSOPT_NONE)
3156 // Create a pair of GOT entries for the module index and
3157 // dtv-relative offset.
3158 Output_data_got<64, false>* got
3159 = target->got_section(symtab, layout);
3160 got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_PAIR,
3161 target->rela_dyn_section(layout),
3162 elfcpp::R_X86_64_DTPMOD64,
3163 elfcpp::R_X86_64_DTPOFF64);
3165 else if (optimized_type == tls::TLSOPT_TO_IE)
3167 // Create a GOT entry for the tp-relative offset.
3168 Output_data_got<64, false>* got
3169 = target->got_section(symtab, layout);
3170 got->add_global_with_rel(gsym, GOT_TYPE_TLS_OFFSET,
3171 target->rela_dyn_section(layout),
3172 elfcpp::R_X86_64_TPOFF64);
3174 else if (optimized_type != tls::TLSOPT_TO_LE)
3175 unsupported_reloc_global(object, r_type, gsym);
3178 case elfcpp::R_X86_64_GOTPC32_TLSDESC:
3179 target->define_tls_base_symbol(symtab, layout);
3180 if (optimized_type == tls::TLSOPT_NONE)
3182 // Create reserved PLT and GOT entries for the resolver.
3183 target->reserve_tlsdesc_entries(symtab, layout);
3185 // Create a double GOT entry with an R_X86_64_TLSDESC
3186 // reloc. The R_X86_64_TLSDESC reloc is resolved
3187 // lazily, so the GOT entry needs to be in an area in
3188 // .got.plt, not .got. Call got_section to make sure
3189 // the section has been created.
3190 target->got_section(symtab, layout);
3191 Output_data_got<64, false>* got = target->got_tlsdesc_section();
3192 Reloc_section* rt = target->rela_tlsdesc_section(layout);
3193 got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_DESC, rt,
3194 elfcpp::R_X86_64_TLSDESC, 0);
3196 else if (optimized_type == tls::TLSOPT_TO_IE)
3198 // Create a GOT entry for the tp-relative offset.
3199 Output_data_got<64, false>* got
3200 = target->got_section(symtab, layout);
3201 got->add_global_with_rel(gsym, GOT_TYPE_TLS_OFFSET,
3202 target->rela_dyn_section(layout),
3203 elfcpp::R_X86_64_TPOFF64);
3205 else if (optimized_type != tls::TLSOPT_TO_LE)
3206 unsupported_reloc_global(object, r_type, gsym);
3209 case elfcpp::R_X86_64_TLSDESC_CALL:
3212 case elfcpp::R_X86_64_TLSLD: // Local-dynamic
3213 if (optimized_type == tls::TLSOPT_NONE)
3215 // Create a GOT entry for the module index.
3216 target->got_mod_index_entry(symtab, layout, object);
3218 else if (optimized_type != tls::TLSOPT_TO_LE)
3219 unsupported_reloc_global(object, r_type, gsym);
3222 case elfcpp::R_X86_64_DTPOFF32:
3223 case elfcpp::R_X86_64_DTPOFF64:
3226 case elfcpp::R_X86_64_GOTTPOFF: // Initial-exec
3227 layout->set_has_static_tls();
3228 if (optimized_type == tls::TLSOPT_NONE)
3230 // Create a GOT entry for the tp-relative offset.
3231 Output_data_got<64, false>* got
3232 = target->got_section(symtab, layout);
3233 got->add_global_with_rel(gsym, GOT_TYPE_TLS_OFFSET,
3234 target->rela_dyn_section(layout),
3235 elfcpp::R_X86_64_TPOFF64);
3237 else if (optimized_type != tls::TLSOPT_TO_LE)
3238 unsupported_reloc_global(object, r_type, gsym);
3241 case elfcpp::R_X86_64_TPOFF32: // Local-exec
3242 layout->set_has_static_tls();
3243 if (parameters->options().shared())
3244 unsupported_reloc_global(object, r_type, gsym);
3253 case elfcpp::R_X86_64_SIZE32:
3254 case elfcpp::R_X86_64_SIZE64:
3256 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
3257 object->name().c_str(), r_type,
3258 gsym->demangled_name().c_str());
3265 Target_x86_64<size>::gc_process_relocs(Symbol_table* symtab,
3267 Sized_relobj_file<size, false>* object,
3268 unsigned int data_shndx,
3269 unsigned int sh_type,
3270 const unsigned char* prelocs,
3272 Output_section* output_section,
3273 bool needs_special_offset_handling,
3274 size_t local_symbol_count,
3275 const unsigned char* plocal_symbols)
3277 typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, false>
3280 if (sh_type == elfcpp::SHT_REL)
3285 gold::gc_process_relocs<size, false, Target_x86_64<size>, Scan,
3295 needs_special_offset_handling,
3300 // Scan relocations for a section.
3304 Target_x86_64<size>::scan_relocs(Symbol_table* symtab,
3306 Sized_relobj_file<size, false>* object,
3307 unsigned int data_shndx,
3308 unsigned int sh_type,
3309 const unsigned char* prelocs,
3311 Output_section* output_section,
3312 bool needs_special_offset_handling,
3313 size_t local_symbol_count,
3314 const unsigned char* plocal_symbols)
3316 typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, false>
3319 if (sh_type == elfcpp::SHT_REL)
3321 gold_error(_("%s: unsupported REL reloc section"),
3322 object->name().c_str());
3326 gold::scan_relocs<size, false, Target_x86_64<size>, Scan, Classify_reloc>(
3335 needs_special_offset_handling,
3340 // Finalize the sections.
3344 Target_x86_64<size>::do_finalize_sections(
3346 const Input_objects*,
3347 Symbol_table* symtab)
3349 const Reloc_section* rel_plt = (this->plt_ == NULL
3351 : this->plt_->rela_plt());
3352 layout->add_target_dynamic_tags(false, this->got_plt_, rel_plt,
3353 this->rela_dyn_, true, false);
3355 // Fill in some more dynamic tags.
3356 Output_data_dynamic* const odyn = layout->dynamic_data();
3359 if (this->plt_ != NULL
3360 && this->plt_->output_section() != NULL
3361 && this->plt_->has_tlsdesc_entry())
3363 unsigned int plt_offset = this->plt_->get_tlsdesc_plt_offset();
3364 unsigned int got_offset = this->plt_->get_tlsdesc_got_offset();
3365 this->got_->finalize_data_size();
3366 odyn->add_section_plus_offset(elfcpp::DT_TLSDESC_PLT,
3367 this->plt_, plt_offset);
3368 odyn->add_section_plus_offset(elfcpp::DT_TLSDESC_GOT,
3369 this->got_, got_offset);
3373 // Emit any relocs we saved in an attempt to avoid generating COPY
3375 if (this->copy_relocs_.any_saved_relocs())
3376 this->copy_relocs_.emit(this->rela_dyn_section(layout));
3378 // Set the size of the _GLOBAL_OFFSET_TABLE_ symbol to the size of
3379 // the .got.plt section.
3380 Symbol* sym = this->global_offset_table_;
3383 uint64_t data_size = this->got_plt_->current_data_size();
3384 symtab->get_sized_symbol<size>(sym)->set_symsize(data_size);
3387 if (parameters->doing_static_link()
3388 && (this->plt_ == NULL || !this->plt_->has_irelative_section()))
3390 // If linking statically, make sure that the __rela_iplt symbols
3391 // were defined if necessary, even if we didn't create a PLT.
3392 static const Define_symbol_in_segment syms[] =
3395 "__rela_iplt_start", // name
3396 elfcpp::PT_LOAD, // segment_type
3397 elfcpp::PF_W, // segment_flags_set
3398 elfcpp::PF(0), // segment_flags_clear
3401 elfcpp::STT_NOTYPE, // type
3402 elfcpp::STB_GLOBAL, // binding
3403 elfcpp::STV_HIDDEN, // visibility
3405 Symbol::SEGMENT_START, // offset_from_base
3409 "__rela_iplt_end", // name
3410 elfcpp::PT_LOAD, // segment_type
3411 elfcpp::PF_W, // segment_flags_set
3412 elfcpp::PF(0), // segment_flags_clear
3415 elfcpp::STT_NOTYPE, // type
3416 elfcpp::STB_GLOBAL, // binding
3417 elfcpp::STV_HIDDEN, // visibility
3419 Symbol::SEGMENT_START, // offset_from_base
3424 symtab->define_symbols(layout, 2, syms,
3425 layout->script_options()->saw_sections_clause());
3429 // For x32, we need to handle PC-relative relocations using full 64-bit
3430 // arithmetic, so that we can detect relocation overflows properly.
3431 // This class overrides the pcrela32_check methods from the defaults in
3432 // Relocate_functions in reloc.h.
3435 class X86_64_relocate_functions : public Relocate_functions<size, false>
3438 typedef Relocate_functions<size, false> Base;
3440 // Do a simple PC relative relocation with the addend in the
3442 static inline typename Base::Reloc_status
3443 pcrela32_check(unsigned char* view,
3444 typename elfcpp::Elf_types<64>::Elf_Addr value,
3445 typename elfcpp::Elf_types<64>::Elf_Swxword addend,
3446 typename elfcpp::Elf_types<64>::Elf_Addr address)
3448 typedef typename elfcpp::Swap<32, false>::Valtype Valtype;
3449 Valtype* wv = reinterpret_cast<Valtype*>(view);
3450 value = value + addend - address;
3451 elfcpp::Swap<32, false>::writeval(wv, value);
3452 return (Bits<32>::has_overflow(value)
3453 ? Base::RELOC_OVERFLOW : Base::RELOC_OK);
3456 // Do a simple PC relative relocation with a Symbol_value with the
3457 // addend in the relocation.
3458 static inline typename Base::Reloc_status
3459 pcrela32_check(unsigned char* view,
3460 const Sized_relobj_file<size, false>* object,
3461 const Symbol_value<size>* psymval,
3462 typename elfcpp::Elf_types<64>::Elf_Swxword addend,
3463 typename elfcpp::Elf_types<64>::Elf_Addr address)
3465 typedef typename elfcpp::Swap<32, false>::Valtype Valtype;
3466 Valtype* wv = reinterpret_cast<Valtype*>(view);
3467 typename elfcpp::Elf_types<64>::Elf_Addr value;
3469 value = psymval->value(object, addend);
3472 // For negative addends, get the symbol value without
3473 // the addend, then add the addend using 64-bit arithmetic.
3474 value = psymval->value(object, 0);
3478 elfcpp::Swap<32, false>::writeval(wv, value);
3479 return (Bits<32>::has_overflow(value)
3480 ? Base::RELOC_OVERFLOW : Base::RELOC_OK);
3484 // Perform a relocation.
3488 Target_x86_64<size>::Relocate::relocate(
3489 const Relocate_info<size, false>* relinfo,
3491 Target_x86_64<size>* target,
3494 const unsigned char* preloc,
3495 const Sized_symbol<size>* gsym,
3496 const Symbol_value<size>* psymval,
3497 unsigned char* view,
3498 typename elfcpp::Elf_types<size>::Elf_Addr address,
3499 section_size_type view_size)
3501 typedef X86_64_relocate_functions<size> Reloc_funcs;
3502 const elfcpp::Rela<size, false> rela(preloc);
3503 unsigned int r_type = elfcpp::elf_r_type<size>(rela.get_r_info());
3505 if (this->skip_call_tls_get_addr_)
3507 if ((r_type != elfcpp::R_X86_64_PLT32
3508 && r_type != elfcpp::R_X86_64_GOTPCRELX
3509 && r_type != elfcpp::R_X86_64_PLT32_BND
3510 && r_type != elfcpp::R_X86_64_PC32_BND
3511 && r_type != elfcpp::R_X86_64_PC32)
3513 || strcmp(gsym->name(), "__tls_get_addr") != 0)
3515 gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3516 _("missing expected TLS relocation"));
3520 this->skip_call_tls_get_addr_ = false;
3528 const Sized_relobj_file<size, false>* object = relinfo->object;
3530 // Pick the value to use for symbols defined in the PLT.
3531 Symbol_value<size> symval;
3533 && gsym->use_plt_offset(Scan::get_reference_flags(r_type)))
3535 symval.set_output_value(target->plt_address_for_global(gsym));
3538 else if (gsym == NULL && psymval->is_ifunc_symbol())
3540 unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
3541 if (object->local_has_plt_offset(r_sym))
3543 symval.set_output_value(target->plt_address_for_local(object, r_sym));
3548 const elfcpp::Elf_Xword addend = rela.get_r_addend();
3550 // Get the GOT offset if needed.
3551 // The GOT pointer points to the end of the GOT section.
3552 // We need to subtract the size of the GOT section to get
3553 // the actual offset to use in the relocation.
3554 bool have_got_offset = false;
3555 // Since the actual offset is always negative, we use signed int to
3556 // support 64-bit GOT relocations.
3560 case elfcpp::R_X86_64_GOT32:
3561 case elfcpp::R_X86_64_GOT64:
3562 case elfcpp::R_X86_64_GOTPLT64:
3563 case elfcpp::R_X86_64_GOTPCREL64:
3566 gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
3567 got_offset = gsym->got_offset(GOT_TYPE_STANDARD) - target->got_size();
3571 unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
3572 gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD));
3573 got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD)
3574 - target->got_size());
3576 have_got_offset = true;
3583 typename Reloc_funcs::Reloc_status rstatus = Reloc_funcs::RELOC_OK;
3587 case elfcpp::R_X86_64_NONE:
3588 case elfcpp::R_X86_64_GNU_VTINHERIT:
3589 case elfcpp::R_X86_64_GNU_VTENTRY:
3592 case elfcpp::R_X86_64_64:
3593 Reloc_funcs::rela64(view, object, psymval, addend);
3596 case elfcpp::R_X86_64_PC64:
3597 Reloc_funcs::pcrela64(view, object, psymval, addend,
3601 case elfcpp::R_X86_64_32:
3602 rstatus = Reloc_funcs::rela32_check(view, object, psymval, addend,
3603 Reloc_funcs::CHECK_UNSIGNED);
3606 case elfcpp::R_X86_64_32S:
3607 rstatus = Reloc_funcs::rela32_check(view, object, psymval, addend,
3608 Reloc_funcs::CHECK_SIGNED);
3611 case elfcpp::R_X86_64_PC32:
3612 case elfcpp::R_X86_64_PC32_BND:
3613 rstatus = Reloc_funcs::pcrela32_check(view, object, psymval, addend,
3617 case elfcpp::R_X86_64_16:
3618 Reloc_funcs::rela16(view, object, psymval, addend);
3621 case elfcpp::R_X86_64_PC16:
3622 Reloc_funcs::pcrela16(view, object, psymval, addend, address);
3625 case elfcpp::R_X86_64_8:
3626 Reloc_funcs::rela8(view, object, psymval, addend);
3629 case elfcpp::R_X86_64_PC8:
3630 Reloc_funcs::pcrela8(view, object, psymval, addend, address);
3633 case elfcpp::R_X86_64_PLT32:
3634 case elfcpp::R_X86_64_PLT32_BND:
3635 gold_assert(gsym == NULL
3636 || gsym->has_plt_offset()
3637 || gsym->final_value_is_known()
3638 || (gsym->is_defined()
3639 && !gsym->is_from_dynobj()
3640 && !gsym->is_preemptible()));
3641 // Note: while this code looks the same as for R_X86_64_PC32, it
3642 // behaves differently because psymval was set to point to
3643 // the PLT entry, rather than the symbol, in Scan::global().
3644 rstatus = Reloc_funcs::pcrela32_check(view, object, psymval, addend,
3648 case elfcpp::R_X86_64_PLTOFF64:
3651 gold_assert(gsym->has_plt_offset()
3652 || gsym->final_value_is_known());
3653 typename elfcpp::Elf_types<size>::Elf_Addr got_address;
3654 // This is the address of GLOBAL_OFFSET_TABLE.
3655 got_address = target->got_plt_section()->address();
3656 Reloc_funcs::rela64(view, object, psymval, addend - got_address);
3660 case elfcpp::R_X86_64_GOT32:
3661 gold_assert(have_got_offset);
3662 Reloc_funcs::rela32(view, got_offset, addend);
3665 case elfcpp::R_X86_64_GOTPC32:
3668 typename elfcpp::Elf_types<size>::Elf_Addr value;
3669 value = target->got_plt_section()->address();
3670 Reloc_funcs::pcrela32_check(view, value, addend, address);
3674 case elfcpp::R_X86_64_GOT64:
3675 case elfcpp::R_X86_64_GOTPLT64:
3676 // R_X86_64_GOTPLT64 is obsolete and treated the the same as
3678 gold_assert(have_got_offset);
3679 Reloc_funcs::rela64(view, got_offset, addend);
3682 case elfcpp::R_X86_64_GOTPC64:
3685 typename elfcpp::Elf_types<size>::Elf_Addr value;
3686 value = target->got_plt_section()->address();
3687 Reloc_funcs::pcrela64(view, value, addend, address);
3691 case elfcpp::R_X86_64_GOTOFF64:
3693 typename elfcpp::Elf_types<size>::Elf_Addr value;
3694 value = (psymval->value(object, 0)
3695 - target->got_plt_section()->address());
3696 Reloc_funcs::rela64(view, value, addend);
3700 case elfcpp::R_X86_64_GOTPCREL:
3701 case elfcpp::R_X86_64_GOTPCRELX:
3702 case elfcpp::R_X86_64_REX_GOTPCRELX:
3705 // mov foo@GOTPCREL(%rip), %reg
3706 // to lea foo(%rip), %reg.
3709 && rela.get_r_offset() >= 2
3711 && !psymval->is_ifunc_symbol())
3713 && rela.get_r_offset() >= 2
3714 && Target_x86_64<size>::can_convert_mov_to_lea(gsym, r_type,
3718 Reloc_funcs::pcrela32(view, object, psymval, addend, address);
3721 // callq *foo@GOTPCRELX(%rip) to
3723 // and jmpq *foo@GOTPCRELX(%rip) to
3726 else if (gsym != NULL
3727 && rela.get_r_offset() >= 2
3728 && Target_x86_64<size>::can_convert_callq_to_direct(gsym,
3732 if (view[-1] == 0x15)
3734 // Convert callq *foo@GOTPCRELX(%rip) to addr32 callq.
3735 // Opcode of addr32 is 0x67 and opcode of direct callq is 0xe8.
3738 // Convert GOTPCRELX to 32-bit pc relative reloc.
3739 Reloc_funcs::pcrela32(view, object, psymval, addend, address);
3743 // Convert jmpq *foo@GOTPCRELX(%rip) to
3746 // The opcode of direct jmpq is 0xe9.
3748 // The opcode of nop is 0x90.
3750 // Convert GOTPCRELX to 32-bit pc relative reloc. jmpq is rip
3751 // relative and since the instruction following the jmpq is now
3752 // the nop, offset the address by 1 byte. The start of the
3753 // relocation also moves ahead by 1 byte.
3754 Reloc_funcs::pcrela32(&view[-1], object, psymval, addend,
3762 gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
3763 got_offset = gsym->got_offset(GOT_TYPE_STANDARD) - target->got_size();
3767 unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
3768 gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD));
3769 got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD)
3770 - target->got_size());
3772 typename elfcpp::Elf_types<size>::Elf_Addr value;
3773 value = target->got_plt_section()->address() + got_offset;
3774 Reloc_funcs::pcrela32_check(view, value, addend, address);
3779 case elfcpp::R_X86_64_GOTPCREL64:
3781 gold_assert(have_got_offset);
3782 typename elfcpp::Elf_types<size>::Elf_Addr value;
3783 value = target->got_plt_section()->address() + got_offset;
3784 Reloc_funcs::pcrela64(view, value, addend, address);
3788 case elfcpp::R_X86_64_COPY:
3789 case elfcpp::R_X86_64_GLOB_DAT:
3790 case elfcpp::R_X86_64_JUMP_SLOT:
3791 case elfcpp::R_X86_64_RELATIVE:
3792 case elfcpp::R_X86_64_IRELATIVE:
3793 // These are outstanding tls relocs, which are unexpected when linking
3794 case elfcpp::R_X86_64_TPOFF64:
3795 case elfcpp::R_X86_64_DTPMOD64:
3796 case elfcpp::R_X86_64_TLSDESC:
3797 gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3798 _("unexpected reloc %u in object file"),
3802 // These are initial tls relocs, which are expected when linking
3803 case elfcpp::R_X86_64_TLSGD: // Global-dynamic
3804 case elfcpp::R_X86_64_GOTPC32_TLSDESC: // Global-dynamic (from ~oliva url)
3805 case elfcpp::R_X86_64_TLSDESC_CALL:
3806 case elfcpp::R_X86_64_TLSLD: // Local-dynamic
3807 case elfcpp::R_X86_64_DTPOFF32:
3808 case elfcpp::R_X86_64_DTPOFF64:
3809 case elfcpp::R_X86_64_GOTTPOFF: // Initial-exec
3810 case elfcpp::R_X86_64_TPOFF32: // Local-exec
3811 this->relocate_tls(relinfo, target, relnum, rela, r_type, gsym, psymval,
3812 view, address, view_size);
3815 case elfcpp::R_X86_64_SIZE32:
3816 case elfcpp::R_X86_64_SIZE64:
3818 gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3819 _("unsupported reloc %u"),
3824 if (rstatus == Reloc_funcs::RELOC_OVERFLOW)
3828 unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
3829 gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3830 _("relocation overflow: "
3831 "reference to local symbol %u in %s"),
3832 r_sym, object->name().c_str());
3834 else if (gsym->is_defined() && gsym->source() == Symbol::FROM_OBJECT)
3836 gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3837 _("relocation overflow: "
3838 "reference to '%s' defined in %s"),
3840 gsym->object()->name().c_str());
3844 gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3845 _("relocation overflow: reference to '%s'"),
3853 // Perform a TLS relocation.
3857 Target_x86_64<size>::Relocate::relocate_tls(
3858 const Relocate_info<size, false>* relinfo,
3859 Target_x86_64<size>* target,
3861 const elfcpp::Rela<size, false>& rela,
3862 unsigned int r_type,
3863 const Sized_symbol<size>* gsym,
3864 const Symbol_value<size>* psymval,
3865 unsigned char* view,
3866 typename elfcpp::Elf_types<size>::Elf_Addr address,
3867 section_size_type view_size)
3869 Output_segment* tls_segment = relinfo->layout->tls_segment();
3871 const Sized_relobj_file<size, false>* object = relinfo->object;
3872 const elfcpp::Elf_Xword addend = rela.get_r_addend();
3873 elfcpp::Shdr<size, false> data_shdr(relinfo->data_shdr);
3874 bool is_executable = (data_shdr.get_sh_flags() & elfcpp::SHF_EXECINSTR) != 0;
3876 typename elfcpp::Elf_types<size>::Elf_Addr value = psymval->value(relinfo->object, 0);
3878 const bool is_final = (gsym == NULL
3879 ? !parameters->options().shared()
3880 : gsym->final_value_is_known());
3881 tls::Tls_optimization optimized_type
3882 = Target_x86_64<size>::optimize_tls_reloc(is_final, r_type);
3885 case elfcpp::R_X86_64_TLSGD: // Global-dynamic
3886 if (!is_executable && optimized_type == tls::TLSOPT_TO_LE)
3888 // If this code sequence is used in a non-executable section,
3889 // we will not optimize the R_X86_64_DTPOFF32/64 relocation,
3890 // on the assumption that it's being used by itself in a debug
3891 // section. Therefore, in the unlikely event that the code
3892 // sequence appears in a non-executable section, we simply
3893 // leave it unoptimized.
3894 optimized_type = tls::TLSOPT_NONE;
3896 if (optimized_type == tls::TLSOPT_TO_LE)
3898 if (tls_segment == NULL)
3900 gold_assert(parameters->errors()->error_count() > 0
3901 || issue_undefined_symbol_error(gsym));
3904 this->tls_gd_to_le(relinfo, relnum, tls_segment,
3905 rela, r_type, value, view,
3911 unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE
3912 ? GOT_TYPE_TLS_OFFSET
3913 : GOT_TYPE_TLS_PAIR);
3914 unsigned int got_offset;
3917 gold_assert(gsym->has_got_offset(got_type));
3918 got_offset = gsym->got_offset(got_type) - target->got_size();
3922 unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
3923 gold_assert(object->local_has_got_offset(r_sym, got_type));
3924 got_offset = (object->local_got_offset(r_sym, got_type)
3925 - target->got_size());
3927 if (optimized_type == tls::TLSOPT_TO_IE)
3929 value = target->got_plt_section()->address() + got_offset;
3930 this->tls_gd_to_ie(relinfo, relnum, rela, r_type,
3931 value, view, address, view_size);
3934 else if (optimized_type == tls::TLSOPT_NONE)
3936 // Relocate the field with the offset of the pair of GOT
3938 value = target->got_plt_section()->address() + got_offset;
3939 Relocate_functions<size, false>::pcrela32(view, value, addend,
3944 gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3945 _("unsupported reloc %u"), r_type);
3948 case elfcpp::R_X86_64_GOTPC32_TLSDESC: // Global-dynamic (from ~oliva url)
3949 case elfcpp::R_X86_64_TLSDESC_CALL:
3950 if (!is_executable && optimized_type == tls::TLSOPT_TO_LE)
3952 // See above comment for R_X86_64_TLSGD.
3953 optimized_type = tls::TLSOPT_NONE;
3955 if (optimized_type == tls::TLSOPT_TO_LE)
3957 if (tls_segment == NULL)
3959 gold_assert(parameters->errors()->error_count() > 0
3960 || issue_undefined_symbol_error(gsym));
3963 this->tls_desc_gd_to_le(relinfo, relnum, tls_segment,
3964 rela, r_type, value, view,
3970 unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE
3971 ? GOT_TYPE_TLS_OFFSET
3972 : GOT_TYPE_TLS_DESC);
3973 unsigned int got_offset = 0;
3974 if (r_type == elfcpp::R_X86_64_GOTPC32_TLSDESC
3975 && optimized_type == tls::TLSOPT_NONE)
3977 // We created GOT entries in the .got.tlsdesc portion of
3978 // the .got.plt section, but the offset stored in the
3979 // symbol is the offset within .got.tlsdesc.
3980 got_offset = (target->got_size()
3981 + target->got_plt_section()->data_size());
3985 gold_assert(gsym->has_got_offset(got_type));
3986 got_offset += gsym->got_offset(got_type) - target->got_size();
3990 unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
3991 gold_assert(object->local_has_got_offset(r_sym, got_type));
3992 got_offset += (object->local_got_offset(r_sym, got_type)
3993 - target->got_size());
3995 if (optimized_type == tls::TLSOPT_TO_IE)
3997 value = target->got_plt_section()->address() + got_offset;
3998 this->tls_desc_gd_to_ie(relinfo, relnum,
3999 rela, r_type, value, view, address,
4003 else if (optimized_type == tls::TLSOPT_NONE)
4005 if (r_type == elfcpp::R_X86_64_GOTPC32_TLSDESC)
4007 // Relocate the field with the offset of the pair of GOT
4009 value = target->got_plt_section()->address() + got_offset;
4010 Relocate_functions<size, false>::pcrela32(view, value, addend,
4016 gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
4017 _("unsupported reloc %u"), r_type);
4020 case elfcpp::R_X86_64_TLSLD: // Local-dynamic
4021 if (!is_executable && optimized_type == tls::TLSOPT_TO_LE)
4023 // See above comment for R_X86_64_TLSGD.
4024 optimized_type = tls::TLSOPT_NONE;
4026 if (optimized_type == tls::TLSOPT_TO_LE)
4028 if (tls_segment == NULL)
4030 gold_assert(parameters->errors()->error_count() > 0
4031 || issue_undefined_symbol_error(gsym));
4034 this->tls_ld_to_le(relinfo, relnum, tls_segment, rela, r_type,
4035 value, view, view_size);
4038 else if (optimized_type == tls::TLSOPT_NONE)
4040 // Relocate the field with the offset of the GOT entry for
4041 // the module index.
4042 unsigned int got_offset;
4043 got_offset = (target->got_mod_index_entry(NULL, NULL, NULL)
4044 - target->got_size());
4045 value = target->got_plt_section()->address() + got_offset;
4046 Relocate_functions<size, false>::pcrela32(view, value, addend,
4050 gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
4051 _("unsupported reloc %u"), r_type);
4054 case elfcpp::R_X86_64_DTPOFF32:
4055 // This relocation type is used in debugging information.
4056 // In that case we need to not optimize the value. If the
4057 // section is not executable, then we assume we should not
4058 // optimize this reloc. See comments above for R_X86_64_TLSGD,
4059 // R_X86_64_GOTPC32_TLSDESC, R_X86_64_TLSDESC_CALL, and
4061 if (optimized_type == tls::TLSOPT_TO_LE && is_executable)
4063 if (tls_segment == NULL)
4065 gold_assert(parameters->errors()->error_count() > 0
4066 || issue_undefined_symbol_error(gsym));
4069 value -= tls_segment->memsz();
4071 Relocate_functions<size, false>::rela32(view, value, addend);
4074 case elfcpp::R_X86_64_DTPOFF64:
4075 // See R_X86_64_DTPOFF32, just above, for why we check for is_executable.
4076 if (optimized_type == tls::TLSOPT_TO_LE && is_executable)
4078 if (tls_segment == NULL)
4080 gold_assert(parameters->errors()->error_count() > 0
4081 || issue_undefined_symbol_error(gsym));
4084 value -= tls_segment->memsz();
4086 Relocate_functions<size, false>::rela64(view, value, addend);
4089 case elfcpp::R_X86_64_GOTTPOFF: // Initial-exec
4091 && gsym->is_undefined()
4092 && parameters->options().output_is_executable())
4094 Target_x86_64<size>::Relocate::tls_ie_to_le(relinfo, relnum,
4096 r_type, value, view,
4100 else if (optimized_type == tls::TLSOPT_TO_LE)
4102 if (tls_segment == NULL)
4104 gold_assert(parameters->errors()->error_count() > 0
4105 || issue_undefined_symbol_error(gsym));
4108 Target_x86_64<size>::Relocate::tls_ie_to_le(relinfo, relnum,
4110 r_type, value, view,
4114 else if (optimized_type == tls::TLSOPT_NONE)
4116 // Relocate the field with the offset of the GOT entry for
4117 // the tp-relative offset of the symbol.
4118 unsigned int got_offset;
4121 gold_assert(gsym->has_got_offset(GOT_TYPE_TLS_OFFSET));
4122 got_offset = (gsym->got_offset(GOT_TYPE_TLS_OFFSET)
4123 - target->got_size());
4127 unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
4128 gold_assert(object->local_has_got_offset(r_sym,
4129 GOT_TYPE_TLS_OFFSET));
4130 got_offset = (object->local_got_offset(r_sym, GOT_TYPE_TLS_OFFSET)
4131 - target->got_size());
4133 value = target->got_plt_section()->address() + got_offset;
4134 Relocate_functions<size, false>::pcrela32(view, value, addend,
4138 gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
4139 _("unsupported reloc type %u"),
4143 case elfcpp::R_X86_64_TPOFF32: // Local-exec
4144 if (tls_segment == NULL)
4146 gold_assert(parameters->errors()->error_count() > 0
4147 || issue_undefined_symbol_error(gsym));
4150 value -= tls_segment->memsz();
4151 Relocate_functions<size, false>::rela32(view, value, addend);
4156 // Do a relocation in which we convert a TLS General-Dynamic to an
4161 Target_x86_64<size>::Relocate::tls_gd_to_ie(
4162 const Relocate_info<size, false>* relinfo,
4164 const elfcpp::Rela<size, false>& rela,
4166 typename elfcpp::Elf_types<size>::Elf_Addr value,
4167 unsigned char* view,
4168 typename elfcpp::Elf_types<size>::Elf_Addr address,
4169 section_size_type view_size)
4172 // .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
4173 // .word 0x6666; rex64; call __tls_get_addr@PLT
4174 // ==> movq %fs:0,%rax; addq x@gottpoff(%rip),%rax
4175 // .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
4176 // .word 0x66; rex64; call *__tls_get_addr@GOTPCREL(%rip)
4177 // ==> movq %fs:0,%rax; addq x@gottpoff(%rip),%rax
4179 // leaq foo@tlsgd(%rip),%rdi;
4180 // .word 0x6666; rex64; call __tls_get_addr@PLT
4181 // ==> movl %fs:0,%eax; addq x@gottpoff(%rip),%rax
4182 // leaq foo@tlsgd(%rip),%rdi;
4183 // .word 0x66; rex64; call *__tls_get_addr@GOTPCREL(%rip)
4184 // ==> movl %fs:0,%eax; addq x@gottpoff(%rip),%rax
4186 tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 12);
4187 tls::check_tls(relinfo, relnum, rela.get_r_offset(),
4188 (memcmp(view + 4, "\x66\x66\x48\xe8", 4) == 0
4189 || memcmp(view + 4, "\x66\x48\xff", 3) == 0));
4193 tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size,
4195 tls::check_tls(relinfo, relnum, rela.get_r_offset(),
4196 (memcmp(view - 4, "\x66\x48\x8d\x3d", 4) == 0));
4197 memcpy(view - 4, "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x03\x05\0\0\0\0",
4202 tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size,
4204 tls::check_tls(relinfo, relnum, rela.get_r_offset(),
4205 (memcmp(view - 3, "\x48\x8d\x3d", 3) == 0));
4206 memcpy(view - 3, "\x64\x8b\x04\x25\0\0\0\0\x48\x03\x05\0\0\0\0",
4210 const elfcpp::Elf_Xword addend = rela.get_r_addend();
4211 Relocate_functions<size, false>::pcrela32(view + 8, value, addend - 8,
4214 // The next reloc should be a PLT32 reloc against __tls_get_addr.
4216 this->skip_call_tls_get_addr_ = true;
4219 // Do a relocation in which we convert a TLS General-Dynamic to a
4224 Target_x86_64<size>::Relocate::tls_gd_to_le(
4225 const Relocate_info<size, false>* relinfo,
4227 Output_segment* tls_segment,
4228 const elfcpp::Rela<size, false>& rela,
4230 typename elfcpp::Elf_types<size>::Elf_Addr value,
4231 unsigned char* view,
4232 section_size_type view_size)
4235 // .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
4236 // .word 0x6666; rex64; call __tls_get_addr@PLT
4237 // ==> movq %fs:0,%rax; leaq x@tpoff(%rax),%rax
4238 // .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
4239 // .word 0x66; rex64; call *__tls_get_addr@GOTPCREL(%rip)
4240 // ==> movq %fs:0,%rax; leaq x@tpoff(%rax),%rax
4242 // leaq foo@tlsgd(%rip),%rdi;
4243 // .word 0x6666; rex64; call __tls_get_addr@PLT
4244 // ==> movl %fs:0,%eax; leaq x@tpoff(%rax),%rax
4245 // leaq foo@tlsgd(%rip),%rdi;
4246 // .word 0x66; rex64; call *__tls_get_addr@GOTPCREL(%rip)
4247 // ==> movl %fs:0,%eax; leaq x@tpoff(%rax),%rax
4249 tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 12);
4250 tls::check_tls(relinfo, relnum, rela.get_r_offset(),
4251 (memcmp(view + 4, "\x66\x66\x48\xe8", 4) == 0
4252 || memcmp(view + 4, "\x66\x48\xff", 3) == 0));
4256 tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size,
4258 tls::check_tls(relinfo, relnum, rela.get_r_offset(),
4259 (memcmp(view - 4, "\x66\x48\x8d\x3d", 4) == 0));
4260 memcpy(view - 4, "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0\0",
4265 tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size,
4267 tls::check_tls(relinfo, relnum, rela.get_r_offset(),
4268 (memcmp(view - 3, "\x48\x8d\x3d", 3) == 0));
4270 memcpy(view - 3, "\x64\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0\0",
4274 value -= tls_segment->memsz();
4275 Relocate_functions<size, false>::rela32(view + 8, value, 0);
4277 // The next reloc should be a PLT32 reloc against __tls_get_addr.
4279 this->skip_call_tls_get_addr_ = true;
4282 // Do a TLSDESC-style General-Dynamic to Initial-Exec transition.
4286 Target_x86_64<size>::Relocate::tls_desc_gd_to_ie(
4287 const Relocate_info<size, false>* relinfo,
4289 const elfcpp::Rela<size, false>& rela,
4290 unsigned int r_type,
4291 typename elfcpp::Elf_types<size>::Elf_Addr value,
4292 unsigned char* view,
4293 typename elfcpp::Elf_types<size>::Elf_Addr address,
4294 section_size_type view_size)
4296 if (r_type == elfcpp::R_X86_64_GOTPC32_TLSDESC)
4298 // leaq foo@tlsdesc(%rip), %rax
4299 // ==> movq foo@gottpoff(%rip), %rax
4300 tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -3);
4301 tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 4);
4302 tls::check_tls(relinfo, relnum, rela.get_r_offset(),
4303 view[-3] == 0x48 && view[-2] == 0x8d && view[-1] == 0x05);
4305 const elfcpp::Elf_Xword addend = rela.get_r_addend();
4306 Relocate_functions<size, false>::pcrela32(view, value, addend, address);
4310 // call *foo@tlscall(%rax)
4312 gold_assert(r_type == elfcpp::R_X86_64_TLSDESC_CALL);
4313 tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 2);
4314 tls::check_tls(relinfo, relnum, rela.get_r_offset(),
4315 view[0] == 0xff && view[1] == 0x10);
4321 // Do a TLSDESC-style General-Dynamic to Local-Exec transition.
4325 Target_x86_64<size>::Relocate::tls_desc_gd_to_le(
4326 const Relocate_info<size, false>* relinfo,
4328 Output_segment* tls_segment,
4329 const elfcpp::Rela<size, false>& rela,
4330 unsigned int r_type,
4331 typename elfcpp::Elf_types<size>::Elf_Addr value,
4332 unsigned char* view,
4333 section_size_type view_size)
4335 if (r_type == elfcpp::R_X86_64_GOTPC32_TLSDESC)
4337 // leaq foo@tlsdesc(%rip), %rax
4338 // ==> movq foo@tpoff, %rax
4339 tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -3);
4340 tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 4);
4341 tls::check_tls(relinfo, relnum, rela.get_r_offset(),
4342 view[-3] == 0x48 && view[-2] == 0x8d && view[-1] == 0x05);
4345 value -= tls_segment->memsz();
4346 Relocate_functions<size, false>::rela32(view, value, 0);
4350 // call *foo@tlscall(%rax)
4352 gold_assert(r_type == elfcpp::R_X86_64_TLSDESC_CALL);
4353 tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 2);
4354 tls::check_tls(relinfo, relnum, rela.get_r_offset(),
4355 view[0] == 0xff && view[1] == 0x10);
4363 Target_x86_64<size>::Relocate::tls_ld_to_le(
4364 const Relocate_info<size, false>* relinfo,
4367 const elfcpp::Rela<size, false>& rela,
4369 typename elfcpp::Elf_types<size>::Elf_Addr,
4370 unsigned char* view,
4371 section_size_type view_size)
4373 // leaq foo@tlsld(%rip),%rdi; call __tls_get_addr@plt;
4375 // ... leq foo@dtpoff(%rax),%reg
4376 // ==> .word 0x6666; .byte 0x66; movq %fs:0,%rax ... leaq x@tpoff(%rax),%rdx
4378 // ... leq foo@dtpoff(%rax),%reg
4379 // ==> nopl 0x0(%rax); movl %fs:0,%eax ... leaq x@tpoff(%rax),%rdx
4380 // leaq foo@tlsld(%rip),%rdi; call *__tls_get_addr@GOTPCREL(%rip)
4382 // ... leq foo@dtpoff(%rax),%reg
4383 // ==> .word 0x6666; .byte 0x6666; movq %fs:0,%rax ... leaq x@tpoff(%rax),%rdx
4385 // ... leq foo@dtpoff(%rax),%reg
4386 // ==> nopw 0x0(%rax); movl %fs:0,%eax ... leaq x@tpoff(%rax),%rdx
4388 tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -3);
4389 tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 9);
4391 tls::check_tls(relinfo, relnum, rela.get_r_offset(),
4392 view[-3] == 0x48 && view[-2] == 0x8d && view[-1] == 0x3d);
4394 tls::check_tls(relinfo, relnum, rela.get_r_offset(),
4395 view[4] == 0xe8 || view[4] == 0xff);
4397 if (view[4] == 0xe8)
4400 memcpy(view - 3, "\x66\x66\x66\x64\x48\x8b\x04\x25\0\0\0\0", 12);
4402 memcpy(view - 3, "\x0f\x1f\x40\x00\x64\x8b\x04\x25\0\0\0\0", 12);
4407 memcpy(view - 3, "\x66\x66\x66\x66\x64\x48\x8b\x04\x25\0\0\0\0",
4410 memcpy(view - 3, "\x66\x0f\x1f\x40\x00\x64\x8b\x04\x25\0\0\0\0",
4414 // The next reloc should be a PLT32 reloc against __tls_get_addr.
4416 this->skip_call_tls_get_addr_ = true;
4419 // Do a relocation in which we convert a TLS Initial-Exec to a
4424 Target_x86_64<size>::Relocate::tls_ie_to_le(
4425 const Relocate_info<size, false>* relinfo,
4427 Output_segment* tls_segment,
4428 const elfcpp::Rela<size, false>& rela,
4430 typename elfcpp::Elf_types<size>::Elf_Addr value,
4431 unsigned char* view,
4432 section_size_type view_size)
4434 // We need to examine the opcodes to figure out which instruction we
4437 // movq foo@gottpoff(%rip),%reg ==> movq $YY,%reg
4438 // addq foo@gottpoff(%rip),%reg ==> addq $YY,%reg
4440 tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -3);
4441 tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 4);
4443 unsigned char op1 = view[-3];
4444 unsigned char op2 = view[-2];
4445 unsigned char op3 = view[-1];
4446 unsigned char reg = op3 >> 3;
4453 else if (size == 32 && op1 == 0x44)
4456 view[-1] = 0xc0 | reg;
4460 // Special handling for %rsp.
4463 else if (size == 32 && op1 == 0x44)
4466 view[-1] = 0xc0 | reg;
4473 else if (size == 32 && op1 == 0x44)
4476 view[-1] = 0x80 | reg | (reg << 3);
4479 if (tls_segment != NULL)
4480 value -= tls_segment->memsz();
4481 Relocate_functions<size, false>::rela32(view, value, 0);
4484 // Relocate section data.
4488 Target_x86_64<size>::relocate_section(
4489 const Relocate_info<size, false>* relinfo,
4490 unsigned int sh_type,
4491 const unsigned char* prelocs,
4493 Output_section* output_section,
4494 bool needs_special_offset_handling,
4495 unsigned char* view,
4496 typename elfcpp::Elf_types<size>::Elf_Addr address,
4497 section_size_type view_size,
4498 const Reloc_symbol_changes* reloc_symbol_changes)
4500 typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, false>
4503 gold_assert(sh_type == elfcpp::SHT_RELA);
4505 gold::relocate_section<size, false, Target_x86_64<size>, Relocate,
4506 gold::Default_comdat_behavior, Classify_reloc>(
4512 needs_special_offset_handling,
4516 reloc_symbol_changes);
4519 // Apply an incremental relocation. Incremental relocations always refer
4520 // to global symbols.
4524 Target_x86_64<size>::apply_relocation(
4525 const Relocate_info<size, false>* relinfo,
4526 typename elfcpp::Elf_types<size>::Elf_Addr r_offset,
4527 unsigned int r_type,
4528 typename elfcpp::Elf_types<size>::Elf_Swxword r_addend,
4530 unsigned char* view,
4531 typename elfcpp::Elf_types<size>::Elf_Addr address,
4532 section_size_type view_size)
4534 gold::apply_relocation<size, false, Target_x86_64<size>,
4535 typename Target_x86_64<size>::Relocate>(
4547 // Scan the relocs during a relocatable link.
4551 Target_x86_64<size>::scan_relocatable_relocs(
4552 Symbol_table* symtab,
4554 Sized_relobj_file<size, false>* object,
4555 unsigned int data_shndx,
4556 unsigned int sh_type,
4557 const unsigned char* prelocs,
4559 Output_section* output_section,
4560 bool needs_special_offset_handling,
4561 size_t local_symbol_count,
4562 const unsigned char* plocal_symbols,
4563 Relocatable_relocs* rr)
4565 typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, false>
4567 typedef gold::Default_scan_relocatable_relocs<Classify_reloc>
4568 Scan_relocatable_relocs;
4570 gold_assert(sh_type == elfcpp::SHT_RELA);
4572 gold::scan_relocatable_relocs<size, false, Scan_relocatable_relocs>(
4580 needs_special_offset_handling,
4586 // Scan the relocs for --emit-relocs.
4590 Target_x86_64<size>::emit_relocs_scan(
4591 Symbol_table* symtab,
4593 Sized_relobj_file<size, false>* object,
4594 unsigned int data_shndx,
4595 unsigned int sh_type,
4596 const unsigned char* prelocs,
4598 Output_section* output_section,
4599 bool needs_special_offset_handling,
4600 size_t local_symbol_count,
4601 const unsigned char* plocal_syms,
4602 Relocatable_relocs* rr)
4604 typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, false>
4606 typedef gold::Default_emit_relocs_strategy<Classify_reloc>
4607 Emit_relocs_strategy;
4609 gold_assert(sh_type == elfcpp::SHT_RELA);
4611 gold::scan_relocatable_relocs<size, false, Emit_relocs_strategy>(
4619 needs_special_offset_handling,
4625 // Relocate a section during a relocatable link.
4629 Target_x86_64<size>::relocate_relocs(
4630 const Relocate_info<size, false>* relinfo,
4631 unsigned int sh_type,
4632 const unsigned char* prelocs,
4634 Output_section* output_section,
4635 typename elfcpp::Elf_types<size>::Elf_Off offset_in_output_section,
4636 unsigned char* view,
4637 typename elfcpp::Elf_types<size>::Elf_Addr view_address,
4638 section_size_type view_size,
4639 unsigned char* reloc_view,
4640 section_size_type reloc_view_size)
4642 typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, false>
4645 gold_assert(sh_type == elfcpp::SHT_RELA);
4647 gold::relocate_relocs<size, false, Classify_reloc>(
4652 offset_in_output_section,
4660 // Return the value to use for a dynamic which requires special
4661 // treatment. This is how we support equality comparisons of function
4662 // pointers across shared library boundaries, as described in the
4663 // processor specific ABI supplement.
4667 Target_x86_64<size>::do_dynsym_value(const Symbol* gsym) const
4669 gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset());
4670 return this->plt_address_for_global(gsym);
4673 // Return a string used to fill a code section with nops to take up
4674 // the specified length.
4678 Target_x86_64<size>::do_code_fill(section_size_type length) const
4682 // Build a jmpq instruction to skip over the bytes.
4683 unsigned char jmp[5];
4685 elfcpp::Swap_unaligned<32, false>::writeval(jmp + 1, length - 5);
4686 return (std::string(reinterpret_cast<char*>(&jmp[0]), 5)
4687 + std::string(length - 5, static_cast<char>(0x90)));
4690 // Nop sequences of various lengths.
4691 const char nop1[1] = { '\x90' }; // nop
4692 const char nop2[2] = { '\x66', '\x90' }; // xchg %ax %ax
4693 const char nop3[3] = { '\x0f', '\x1f', '\x00' }; // nop (%rax)
4694 const char nop4[4] = { '\x0f', '\x1f', '\x40', // nop 0(%rax)
4696 const char nop5[5] = { '\x0f', '\x1f', '\x44', // nop 0(%rax,%rax,1)
4698 const char nop6[6] = { '\x66', '\x0f', '\x1f', // nopw 0(%rax,%rax,1)
4699 '\x44', '\x00', '\x00' };
4700 const char nop7[7] = { '\x0f', '\x1f', '\x80', // nopl 0L(%rax)
4701 '\x00', '\x00', '\x00',
4703 const char nop8[8] = { '\x0f', '\x1f', '\x84', // nopl 0L(%rax,%rax,1)
4704 '\x00', '\x00', '\x00',
4706 const char nop9[9] = { '\x66', '\x0f', '\x1f', // nopw 0L(%rax,%rax,1)
4707 '\x84', '\x00', '\x00',
4708 '\x00', '\x00', '\x00' };
4709 const char nop10[10] = { '\x66', '\x2e', '\x0f', // nopw %cs:0L(%rax,%rax,1)
4710 '\x1f', '\x84', '\x00',
4711 '\x00', '\x00', '\x00',
4713 const char nop11[11] = { '\x66', '\x66', '\x2e', // data16
4714 '\x0f', '\x1f', '\x84', // nopw %cs:0L(%rax,%rax,1)
4715 '\x00', '\x00', '\x00',
4717 const char nop12[12] = { '\x66', '\x66', '\x66', // data16; data16
4718 '\x2e', '\x0f', '\x1f', // nopw %cs:0L(%rax,%rax,1)
4719 '\x84', '\x00', '\x00',
4720 '\x00', '\x00', '\x00' };
4721 const char nop13[13] = { '\x66', '\x66', '\x66', // data16; data16; data16
4722 '\x66', '\x2e', '\x0f', // nopw %cs:0L(%rax,%rax,1)
4723 '\x1f', '\x84', '\x00',
4724 '\x00', '\x00', '\x00',
4726 const char nop14[14] = { '\x66', '\x66', '\x66', // data16; data16; data16
4727 '\x66', '\x66', '\x2e', // data16
4728 '\x0f', '\x1f', '\x84', // nopw %cs:0L(%rax,%rax,1)
4729 '\x00', '\x00', '\x00',
4731 const char nop15[15] = { '\x66', '\x66', '\x66', // data16; data16; data16
4732 '\x66', '\x66', '\x66', // data16; data16
4733 '\x2e', '\x0f', '\x1f', // nopw %cs:0L(%rax,%rax,1)
4734 '\x84', '\x00', '\x00',
4735 '\x00', '\x00', '\x00' };
4737 const char* nops[16] = {
4739 nop1, nop2, nop3, nop4, nop5, nop6, nop7,
4740 nop8, nop9, nop10, nop11, nop12, nop13, nop14, nop15
4743 return std::string(nops[length], length);
4746 // Return the addend to use for a target specific relocation. The
4747 // only target specific relocation is R_X86_64_TLSDESC for a local
4748 // symbol. We want to set the addend is the offset of the local
4749 // symbol in the TLS segment.
4753 Target_x86_64<size>::do_reloc_addend(void* arg, unsigned int r_type,
4756 gold_assert(r_type == elfcpp::R_X86_64_TLSDESC);
4757 uintptr_t intarg = reinterpret_cast<uintptr_t>(arg);
4758 gold_assert(intarg < this->tlsdesc_reloc_info_.size());
4759 const Tlsdesc_info& ti(this->tlsdesc_reloc_info_[intarg]);
4760 const Symbol_value<size>* psymval = ti.object->local_symbol(ti.r_sym);
4761 gold_assert(psymval->is_tls_symbol());
4762 // The value of a TLS symbol is the offset in the TLS segment.
4763 return psymval->value(ti.object, 0);
4766 // Return the value to use for the base of a DW_EH_PE_datarel offset
4767 // in an FDE. Solaris and SVR4 use DW_EH_PE_datarel because their
4768 // assembler can not write out the difference between two labels in
4769 // different sections, so instead of using a pc-relative value they
4770 // use an offset from the GOT.
4774 Target_x86_64<size>::do_ehframe_datarel_base() const
4776 gold_assert(this->global_offset_table_ != NULL);
4777 Symbol* sym = this->global_offset_table_;
4778 Sized_symbol<size>* ssym = static_cast<Sized_symbol<size>*>(sym);
4779 return ssym->value();
4782 // FNOFFSET in section SHNDX in OBJECT is the start of a function
4783 // compiled with -fsplit-stack. The function calls non-split-stack
4784 // code. We have to change the function so that it always ensures
4785 // that it has enough stack space to run some random function.
4787 static const unsigned char cmp_insn_32[] = { 0x64, 0x3b, 0x24, 0x25 };
4788 static const unsigned char lea_r10_insn_32[] = { 0x44, 0x8d, 0x94, 0x24 };
4789 static const unsigned char lea_r11_insn_32[] = { 0x44, 0x8d, 0x9c, 0x24 };
4791 static const unsigned char cmp_insn_64[] = { 0x64, 0x48, 0x3b, 0x24, 0x25 };
4792 static const unsigned char lea_r10_insn_64[] = { 0x4c, 0x8d, 0x94, 0x24 };
4793 static const unsigned char lea_r11_insn_64[] = { 0x4c, 0x8d, 0x9c, 0x24 };
4797 Target_x86_64<size>::do_calls_non_split(Relobj* object, unsigned int shndx,
4798 section_offset_type fnoffset,
4799 section_size_type fnsize,
4800 const unsigned char*,
4802 unsigned char* view,
4803 section_size_type view_size,
4805 std::string* to) const
4807 const char* const cmp_insn = reinterpret_cast<const char*>
4808 (size == 32 ? cmp_insn_32 : cmp_insn_64);
4809 const char* const lea_r10_insn = reinterpret_cast<const char*>
4810 (size == 32 ? lea_r10_insn_32 : lea_r10_insn_64);
4811 const char* const lea_r11_insn = reinterpret_cast<const char*>
4812 (size == 32 ? lea_r11_insn_32 : lea_r11_insn_64);
4814 const size_t cmp_insn_len =
4815 (size == 32 ? sizeof(cmp_insn_32) : sizeof(cmp_insn_64));
4816 const size_t lea_r10_insn_len =
4817 (size == 32 ? sizeof(lea_r10_insn_32) : sizeof(lea_r10_insn_64));
4818 const size_t lea_r11_insn_len =
4819 (size == 32 ? sizeof(lea_r11_insn_32) : sizeof(lea_r11_insn_64));
4820 const size_t nop_len = (size == 32 ? 7 : 8);
4822 // The function starts with a comparison of the stack pointer and a
4823 // field in the TCB. This is followed by a jump.
4826 if (this->match_view(view, view_size, fnoffset, cmp_insn, cmp_insn_len)
4827 && fnsize > nop_len + 1)
4829 // We will call __morestack if the carry flag is set after this
4830 // comparison. We turn the comparison into an stc instruction
4832 view[fnoffset] = '\xf9';
4833 this->set_view_to_nop(view, view_size, fnoffset + 1, nop_len);
4835 // lea NN(%rsp),%r10
4836 // lea NN(%rsp),%r11
4837 else if ((this->match_view(view, view_size, fnoffset,
4838 lea_r10_insn, lea_r10_insn_len)
4839 || this->match_view(view, view_size, fnoffset,
4840 lea_r11_insn, lea_r11_insn_len))
4843 // This is loading an offset from the stack pointer for a
4844 // comparison. The offset is negative, so we decrease the
4845 // offset by the amount of space we need for the stack. This
4846 // means we will avoid calling __morestack if there happens to
4847 // be plenty of space on the stack already.
4848 unsigned char* pval = view + fnoffset + 4;
4849 uint32_t val = elfcpp::Swap_unaligned<32, false>::readval(pval);
4850 val -= parameters->options().split_stack_adjust_size();
4851 elfcpp::Swap_unaligned<32, false>::writeval(pval, val);
4855 if (!object->has_no_split_stack())
4856 object->error(_("failed to match split-stack sequence at "
4857 "section %u offset %0zx"),
4858 shndx, static_cast<size_t>(fnoffset));
4862 // We have to change the function so that it calls
4863 // __morestack_non_split instead of __morestack. The former will
4864 // allocate additional stack space.
4865 *from = "__morestack";
4866 *to = "__morestack_non_split";
4869 // The selector for x86_64 object files. Note this is never instantiated
4870 // directly. It's only used in Target_selector_x86_64_nacl, below.
4873 class Target_selector_x86_64 : public Target_selector_freebsd
4876 Target_selector_x86_64()
4877 : Target_selector_freebsd(elfcpp::EM_X86_64, size, false,
4879 ? "elf64-x86-64" : "elf32-x86-64"),
4881 ? "elf64-x86-64-freebsd"
4882 : "elf32-x86-64-freebsd"),
4883 (size == 64 ? "elf_x86_64" : "elf32_x86_64"))
4887 do_instantiate_target()
4888 { return new Target_x86_64<size>(); }
4892 // NaCl variant. It uses different PLT contents.
4895 class Output_data_plt_x86_64_nacl : public Output_data_plt_x86_64<size>
4898 Output_data_plt_x86_64_nacl(Layout* layout,
4899 Output_data_got<64, false>* got,
4900 Output_data_got_plt_x86_64* got_plt,
4901 Output_data_space* got_irelative)
4902 : Output_data_plt_x86_64<size>(layout, plt_entry_size,
4903 got, got_plt, got_irelative)
4906 Output_data_plt_x86_64_nacl(Layout* layout,
4907 Output_data_got<64, false>* got,
4908 Output_data_got_plt_x86_64* got_plt,
4909 Output_data_space* got_irelative,
4910 unsigned int plt_count)
4911 : Output_data_plt_x86_64<size>(layout, plt_entry_size,
4912 got, got_plt, got_irelative,
4917 virtual unsigned int
4918 do_get_plt_entry_size() const
4919 { return plt_entry_size; }
4922 do_add_eh_frame(Layout* layout)
4924 layout->add_eh_frame_for_plt(this,
4925 this->plt_eh_frame_cie,
4926 this->plt_eh_frame_cie_size,
4928 plt_eh_frame_fde_size);
4932 do_fill_first_plt_entry(unsigned char* pov,
4933 typename elfcpp::Elf_types<size>::Elf_Addr got_addr,
4934 typename elfcpp::Elf_types<size>::Elf_Addr plt_addr);
4936 virtual unsigned int
4937 do_fill_plt_entry(unsigned char* pov,
4938 typename elfcpp::Elf_types<size>::Elf_Addr got_address,
4939 typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
4940 unsigned int got_offset,
4941 unsigned int plt_offset,
4942 unsigned int plt_index);
4945 do_fill_tlsdesc_entry(unsigned char* pov,
4946 typename elfcpp::Elf_types<size>::Elf_Addr got_address,
4947 typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
4948 typename elfcpp::Elf_types<size>::Elf_Addr got_base,
4949 unsigned int tlsdesc_got_offset,
4950 unsigned int plt_offset);
4953 // The size of an entry in the PLT.
4954 static const int plt_entry_size = 64;
4956 // The first entry in the PLT.
4957 static const unsigned char first_plt_entry[plt_entry_size];
4959 // Other entries in the PLT for an executable.
4960 static const unsigned char plt_entry[plt_entry_size];
4962 // The reserved TLSDESC entry in the PLT for an executable.
4963 static const unsigned char tlsdesc_plt_entry[plt_entry_size];
4965 // The .eh_frame unwind information for the PLT.
4966 static const int plt_eh_frame_fde_size = 32;
4967 static const unsigned char plt_eh_frame_fde[plt_eh_frame_fde_size];
4971 class Target_x86_64_nacl : public Target_x86_64<size>
4974 Target_x86_64_nacl()
4975 : Target_x86_64<size>(&x86_64_nacl_info)
4978 virtual Output_data_plt_x86_64<size>*
4979 do_make_data_plt(Layout* layout,
4980 Output_data_got<64, false>* got,
4981 Output_data_got_plt_x86_64* got_plt,
4982 Output_data_space* got_irelative)
4984 return new Output_data_plt_x86_64_nacl<size>(layout, got, got_plt,
4988 virtual Output_data_plt_x86_64<size>*
4989 do_make_data_plt(Layout* layout,
4990 Output_data_got<64, false>* got,
4991 Output_data_got_plt_x86_64* got_plt,
4992 Output_data_space* got_irelative,
4993 unsigned int plt_count)
4995 return new Output_data_plt_x86_64_nacl<size>(layout, got, got_plt,
5001 do_code_fill(section_size_type length) const;
5004 static const Target::Target_info x86_64_nacl_info;
5008 const Target::Target_info Target_x86_64_nacl<64>::x86_64_nacl_info =
5011 false, // is_big_endian
5012 elfcpp::EM_X86_64, // machine_code
5013 false, // has_make_symbol
5014 false, // has_resolve
5015 true, // has_code_fill
5016 true, // is_default_stack_executable
5017 true, // can_icf_inline_merge_sections
5019 "/lib64/ld-nacl-x86-64.so.1", // dynamic_linker
5020 0x20000, // default_text_segment_address
5021 0x10000, // abi_pagesize (overridable by -z max-page-size)
5022 0x10000, // common_pagesize (overridable by -z common-page-size)
5023 true, // isolate_execinstr
5024 0x10000000, // rosegment_gap
5025 elfcpp::SHN_UNDEF, // small_common_shndx
5026 elfcpp::SHN_X86_64_LCOMMON, // large_common_shndx
5027 0, // small_common_section_flags
5028 elfcpp::SHF_X86_64_LARGE, // large_common_section_flags
5029 NULL, // attributes_section
5030 NULL, // attributes_vendor
5031 "_start", // entry_symbol_name
5032 32, // hash_entry_size
5036 const Target::Target_info Target_x86_64_nacl<32>::x86_64_nacl_info =
5039 false, // is_big_endian
5040 elfcpp::EM_X86_64, // machine_code
5041 false, // has_make_symbol
5042 false, // has_resolve
5043 true, // has_code_fill
5044 true, // is_default_stack_executable
5045 true, // can_icf_inline_merge_sections
5047 "/lib/ld-nacl-x86-64.so.1", // dynamic_linker
5048 0x20000, // default_text_segment_address
5049 0x10000, // abi_pagesize (overridable by -z max-page-size)
5050 0x10000, // common_pagesize (overridable by -z common-page-size)
5051 true, // isolate_execinstr
5052 0x10000000, // rosegment_gap
5053 elfcpp::SHN_UNDEF, // small_common_shndx
5054 elfcpp::SHN_X86_64_LCOMMON, // large_common_shndx
5055 0, // small_common_section_flags
5056 elfcpp::SHF_X86_64_LARGE, // large_common_section_flags
5057 NULL, // attributes_section
5058 NULL, // attributes_vendor
5059 "_start", // entry_symbol_name
5060 32, // hash_entry_size
5063 #define NACLMASK 0xe0 // 32-byte alignment mask.
5065 // The first entry in the PLT.
5069 Output_data_plt_x86_64_nacl<size>::first_plt_entry[plt_entry_size] =
5071 0xff, 0x35, // pushq contents of memory address
5072 0, 0, 0, 0, // replaced with address of .got + 8
5073 0x4c, 0x8b, 0x1d, // mov GOT+16(%rip), %r11
5074 0, 0, 0, 0, // replaced with address of .got + 16
5075 0x41, 0x83, 0xe3, NACLMASK, // and $-32, %r11d
5076 0x4d, 0x01, 0xfb, // add %r15, %r11
5077 0x41, 0xff, 0xe3, // jmpq *%r11
5079 // 9-byte nop sequence to pad out to the next 32-byte boundary.
5080 0x66, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw 0x0(%rax,%rax,1)
5082 // 32 bytes of nop to pad out to the standard size
5083 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, // excess data32 prefixes
5084 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
5085 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, // excess data32 prefixes
5086 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
5087 0x66, // excess data32 prefix
5093 Output_data_plt_x86_64_nacl<size>::do_fill_first_plt_entry(
5095 typename elfcpp::Elf_types<size>::Elf_Addr got_address,
5096 typename elfcpp::Elf_types<size>::Elf_Addr plt_address)
5098 memcpy(pov, first_plt_entry, plt_entry_size);
5099 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
5101 - (plt_address + 2 + 4)));
5102 elfcpp::Swap_unaligned<32, false>::writeval(pov + 9,
5104 - (plt_address + 9 + 4)));
5107 // Subsequent entries in the PLT.
5111 Output_data_plt_x86_64_nacl<size>::plt_entry[plt_entry_size] =
5113 0x4c, 0x8b, 0x1d, // mov name@GOTPCREL(%rip),%r11
5114 0, 0, 0, 0, // replaced with address of symbol in .got
5115 0x41, 0x83, 0xe3, NACLMASK, // and $-32, %r11d
5116 0x4d, 0x01, 0xfb, // add %r15, %r11
5117 0x41, 0xff, 0xe3, // jmpq *%r11
5119 // 15-byte nop sequence to pad out to the next 32-byte boundary.
5120 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, // excess data32 prefixes
5121 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
5123 // Lazy GOT entries point here (32-byte aligned).
5124 0x68, // pushq immediate
5125 0, 0, 0, 0, // replaced with index into relocation table
5126 0xe9, // jmp relative
5127 0, 0, 0, 0, // replaced with offset to start of .plt0
5129 // 22 bytes of nop to pad out to the standard size.
5130 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, // excess data32 prefixes
5131 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
5132 0x0f, 0x1f, 0x80, 0, 0, 0, 0, // nopl 0x0(%rax)
5137 Output_data_plt_x86_64_nacl<size>::do_fill_plt_entry(
5139 typename elfcpp::Elf_types<size>::Elf_Addr got_address,
5140 typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
5141 unsigned int got_offset,
5142 unsigned int plt_offset,
5143 unsigned int plt_index)
5145 memcpy(pov, plt_entry, plt_entry_size);
5146 elfcpp::Swap_unaligned<32, false>::writeval(pov + 3,
5147 (got_address + got_offset
5148 - (plt_address + plt_offset
5151 elfcpp::Swap_unaligned<32, false>::writeval(pov + 33, plt_index);
5152 elfcpp::Swap_unaligned<32, false>::writeval(pov + 38,
5153 - (plt_offset + 38 + 4));
5158 // The reserved TLSDESC entry in the PLT.
5162 Output_data_plt_x86_64_nacl<size>::tlsdesc_plt_entry[plt_entry_size] =
5164 0xff, 0x35, // pushq x(%rip)
5165 0, 0, 0, 0, // replaced with address of linkmap GOT entry (at PLTGOT + 8)
5166 0x4c, 0x8b, 0x1d, // mov y(%rip),%r11
5167 0, 0, 0, 0, // replaced with offset of reserved TLSDESC_GOT entry
5168 0x41, 0x83, 0xe3, NACLMASK, // and $-32, %r11d
5169 0x4d, 0x01, 0xfb, // add %r15, %r11
5170 0x41, 0xff, 0xe3, // jmpq *%r11
5172 // 41 bytes of nop to pad out to the standard size.
5173 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, // excess data32 prefixes
5174 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
5175 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, // excess data32 prefixes
5176 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
5177 0x66, 0x66, // excess data32 prefixes
5178 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
5183 Output_data_plt_x86_64_nacl<size>::do_fill_tlsdesc_entry(
5185 typename elfcpp::Elf_types<size>::Elf_Addr got_address,
5186 typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
5187 typename elfcpp::Elf_types<size>::Elf_Addr got_base,
5188 unsigned int tlsdesc_got_offset,
5189 unsigned int plt_offset)
5191 memcpy(pov, tlsdesc_plt_entry, plt_entry_size);
5192 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
5194 - (plt_address + plt_offset
5196 elfcpp::Swap_unaligned<32, false>::writeval(pov + 9,
5198 + tlsdesc_got_offset
5199 - (plt_address + plt_offset
5203 // The .eh_frame unwind information for the PLT.
5207 Output_data_plt_x86_64_nacl<size>::plt_eh_frame_fde[plt_eh_frame_fde_size] =
5209 0, 0, 0, 0, // Replaced with offset to .plt.
5210 0, 0, 0, 0, // Replaced with size of .plt.
5211 0, // Augmentation size.
5212 elfcpp::DW_CFA_def_cfa_offset, 16, // DW_CFA_def_cfa_offset: 16.
5213 elfcpp::DW_CFA_advance_loc + 6, // Advance 6 to __PLT__ + 6.
5214 elfcpp::DW_CFA_def_cfa_offset, 24, // DW_CFA_def_cfa_offset: 24.
5215 elfcpp::DW_CFA_advance_loc + 58, // Advance 58 to __PLT__ + 64.
5216 elfcpp::DW_CFA_def_cfa_expression, // DW_CFA_def_cfa_expression.
5217 13, // Block length.
5218 elfcpp::DW_OP_breg7, 8, // Push %rsp + 8.
5219 elfcpp::DW_OP_breg16, 0, // Push %rip.
5220 elfcpp::DW_OP_const1u, 63, // Push 0x3f.
5221 elfcpp::DW_OP_and, // & (%rip & 0x3f).
5222 elfcpp::DW_OP_const1u, 37, // Push 0x25.
5223 elfcpp::DW_OP_ge, // >= ((%rip & 0x3f) >= 0x25)
5224 elfcpp::DW_OP_lit3, // Push 3.
5225 elfcpp::DW_OP_shl, // << (((%rip & 0x3f) >= 0x25) << 3)
5226 elfcpp::DW_OP_plus, // + ((((%rip&0x3f)>=0x25)<<3)+%rsp+8
5227 elfcpp::DW_CFA_nop, // Align to 32 bytes.
5231 // Return a string used to fill a code section with nops.
5232 // For NaCl, long NOPs are only valid if they do not cross
5233 // bundle alignment boundaries, so keep it simple with one-byte NOPs.
5236 Target_x86_64_nacl<size>::do_code_fill(section_size_type length) const
5238 return std::string(length, static_cast<char>(0x90));
5241 // The selector for x86_64-nacl object files.
5244 class Target_selector_x86_64_nacl
5245 : public Target_selector_nacl<Target_selector_x86_64<size>,
5246 Target_x86_64_nacl<size> >
5249 Target_selector_x86_64_nacl()
5250 : Target_selector_nacl<Target_selector_x86_64<size>,
5251 Target_x86_64_nacl<size> >("x86-64",
5253 ? "elf64-x86-64-nacl"
5254 : "elf32-x86-64-nacl",
5257 : "elf32_x86_64_nacl")
5261 Target_selector_x86_64_nacl<64> target_selector_x86_64;
5262 Target_selector_x86_64_nacl<32> target_selector_x32;
5264 } // End anonymous namespace.