1 // x86_64.cc -- x86_64 target support for gold.
3 // Copyright 2006, 2007, 2008, 2009, 2010, 2011, 2012
4 // Free Software Foundation, Inc.
5 // Written by Ian Lance Taylor <iant@google.com>.
7 // This file is part of gold.
9 // This program is free software; you can redistribute it and/or modify
10 // it under the terms of the GNU General Public License as published by
11 // the Free Software Foundation; either version 3 of the License, or
12 // (at your option) any later version.
14 // This program is distributed in the hope that it will be useful,
15 // but WITHOUT ANY WARRANTY; without even the implied warranty of
16 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 // GNU General Public License for more details.
19 // You should have received a copy of the GNU General Public License
20 // along with this program; if not, write to the Free Software
21 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
22 // MA 02110-1301, USA.
30 #include "parameters.h"
37 #include "copy-relocs.h"
39 #include "target-reloc.h"
40 #include "target-select.h"
52 // A class to handle the PLT data.
53 // This is an abstract base class that handles most of the linker details
54 // but does not know the actual contents of PLT entries. The derived
55 // classes below fill in those details.
58 class Output_data_plt_x86_64 : public Output_section_data
61 typedef Output_data_reloc<elfcpp::SHT_RELA, true, size, false> Reloc_section;
63 Output_data_plt_x86_64(Layout* layout, uint64_t addralign,
64 Output_data_got<64, false>* got,
65 Output_data_space* got_plt,
66 Output_data_space* got_irelative)
67 : Output_section_data(addralign), layout_(layout), tlsdesc_rel_(NULL),
68 irelative_rel_(NULL), got_(got), got_plt_(got_plt),
69 got_irelative_(got_irelative), count_(0), irelative_count_(0),
70 tlsdesc_got_offset_(-1U), free_list_()
71 { this->init(layout); }
73 Output_data_plt_x86_64(Layout* layout, uint64_t plt_entry_size,
74 Output_data_got<64, false>* got,
75 Output_data_space* got_plt,
76 Output_data_space* got_irelative,
77 unsigned int plt_count)
78 : Output_section_data((plt_count + 1) * plt_entry_size,
79 plt_entry_size, false),
80 layout_(layout), tlsdesc_rel_(NULL), irelative_rel_(NULL), got_(got),
81 got_plt_(got_plt), got_irelative_(got_irelative), count_(plt_count),
82 irelative_count_(0), tlsdesc_got_offset_(-1U), free_list_()
86 // Initialize the free list and reserve the first entry.
87 this->free_list_.init((plt_count + 1) * plt_entry_size, false);
88 this->free_list_.remove(0, plt_entry_size);
91 // Initialize the PLT section.
95 // Add an entry to the PLT.
97 add_entry(Symbol_table*, Layout*, Symbol* gsym);
99 // Add an entry to the PLT for a local STT_GNU_IFUNC symbol.
101 add_local_ifunc_entry(Symbol_table* symtab, Layout*,
102 Sized_relobj_file<size, false>* relobj,
103 unsigned int local_sym_index);
105 // Add the relocation for a PLT entry.
107 add_relocation(Symbol_table*, Layout*, Symbol* gsym,
108 unsigned int got_offset);
110 // Add the reserved TLSDESC_PLT entry to the PLT.
112 reserve_tlsdesc_entry(unsigned int got_offset)
113 { this->tlsdesc_got_offset_ = got_offset; }
115 // Return true if a TLSDESC_PLT entry has been reserved.
117 has_tlsdesc_entry() const
118 { return this->tlsdesc_got_offset_ != -1U; }
120 // Return the GOT offset for the reserved TLSDESC_PLT entry.
122 get_tlsdesc_got_offset() const
123 { return this->tlsdesc_got_offset_; }
125 // Return the offset of the reserved TLSDESC_PLT entry.
127 get_tlsdesc_plt_offset() const
129 return ((this->count_ + this->irelative_count_ + 1)
130 * this->get_plt_entry_size());
133 // Return the .rela.plt section data.
136 { return this->rel_; }
138 // Return where the TLSDESC relocations should go.
140 rela_tlsdesc(Layout*);
142 // Return where the IRELATIVE relocations should go in the PLT
145 rela_irelative(Symbol_table*, Layout*);
147 // Return whether we created a section for IRELATIVE relocations.
149 has_irelative_section() const
150 { return this->irelative_rel_ != NULL; }
152 // Return the number of PLT entries.
155 { return this->count_ + this->irelative_count_; }
157 // Return the offset of the first non-reserved PLT entry.
159 first_plt_entry_offset()
160 { return this->get_plt_entry_size(); }
162 // Return the size of a PLT entry.
164 get_plt_entry_size() const
165 { return this->do_get_plt_entry_size(); }
167 // Reserve a slot in the PLT for an existing symbol in an incremental update.
169 reserve_slot(unsigned int plt_index)
171 this->free_list_.remove((plt_index + 1) * this->get_plt_entry_size(),
172 (plt_index + 2) * this->get_plt_entry_size());
175 // Return the PLT address to use for a global symbol.
177 address_for_global(const Symbol*);
179 // Return the PLT address to use for a local symbol.
181 address_for_local(const Relobj*, unsigned int symndx);
183 // Add .eh_frame information for the PLT.
185 add_eh_frame(Layout* layout)
186 { this->do_add_eh_frame(layout); }
189 // Fill in the first PLT entry.
191 fill_first_plt_entry(unsigned char* pov,
192 typename elfcpp::Elf_types<size>::Elf_Addr got_address,
193 typename elfcpp::Elf_types<size>::Elf_Addr plt_address)
194 { this->do_fill_first_plt_entry(pov, got_address, plt_address); }
196 // Fill in a normal PLT entry. Returns the offset into the entry that
197 // should be the initial GOT slot value.
199 fill_plt_entry(unsigned char* pov,
200 typename elfcpp::Elf_types<size>::Elf_Addr got_address,
201 typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
202 unsigned int got_offset,
203 unsigned int plt_offset,
204 unsigned int plt_index)
206 return this->do_fill_plt_entry(pov, got_address, plt_address,
207 got_offset, plt_offset, plt_index);
210 // Fill in the reserved TLSDESC PLT entry.
212 fill_tlsdesc_entry(unsigned char* pov,
213 typename elfcpp::Elf_types<size>::Elf_Addr got_address,
214 typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
215 typename elfcpp::Elf_types<size>::Elf_Addr got_base,
216 unsigned int tlsdesc_got_offset,
217 unsigned int plt_offset)
219 this->do_fill_tlsdesc_entry(pov, got_address, plt_address, got_base,
220 tlsdesc_got_offset, plt_offset);
224 do_get_plt_entry_size() const = 0;
227 do_fill_first_plt_entry(unsigned char* pov,
228 typename elfcpp::Elf_types<size>::Elf_Addr got_addr,
229 typename elfcpp::Elf_types<size>::Elf_Addr plt_addr)
233 do_fill_plt_entry(unsigned char* pov,
234 typename elfcpp::Elf_types<size>::Elf_Addr got_address,
235 typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
236 unsigned int got_offset,
237 unsigned int plt_offset,
238 unsigned int plt_index) = 0;
241 do_fill_tlsdesc_entry(unsigned char* pov,
242 typename elfcpp::Elf_types<size>::Elf_Addr got_address,
243 typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
244 typename elfcpp::Elf_types<size>::Elf_Addr got_base,
245 unsigned int tlsdesc_got_offset,
246 unsigned int plt_offset) = 0;
249 do_add_eh_frame(Layout* layout) = 0;
252 do_adjust_output_section(Output_section* os);
254 // Write to a map file.
256 do_print_to_mapfile(Mapfile* mapfile) const
257 { mapfile->print_output_data(this, _("** PLT")); }
259 // The CIE of the .eh_frame unwind information for the PLT.
260 static const int plt_eh_frame_cie_size = 16;
261 static const unsigned char plt_eh_frame_cie[plt_eh_frame_cie_size];
264 // Set the final size.
266 set_final_data_size();
268 // Write out the PLT data.
270 do_write(Output_file*);
272 // A pointer to the Layout class, so that we can find the .dynamic
273 // section when we write out the GOT PLT section.
275 // The reloc section.
277 // The TLSDESC relocs, if necessary. These must follow the regular
279 Reloc_section* tlsdesc_rel_;
280 // The IRELATIVE relocs, if necessary. These must follow the
281 // regular PLT relocations and the TLSDESC relocations.
282 Reloc_section* irelative_rel_;
284 Output_data_got<64, false>* got_;
285 // The .got.plt section.
286 Output_data_space* got_plt_;
287 // The part of the .got.plt section used for IRELATIVE relocs.
288 Output_data_space* got_irelative_;
289 // The number of PLT entries.
291 // Number of PLT entries with R_X86_64_IRELATIVE relocs. These
292 // follow the regular PLT entries.
293 unsigned int irelative_count_;
294 // Offset of the reserved TLSDESC_GOT entry when needed.
295 unsigned int tlsdesc_got_offset_;
296 // List of available regions within the section, for incremental
298 Free_list free_list_;
302 class Output_data_plt_x86_64_standard : public Output_data_plt_x86_64<size>
305 Output_data_plt_x86_64_standard(Layout* layout,
306 Output_data_got<64, false>* got,
307 Output_data_space* got_plt,
308 Output_data_space* got_irelative)
309 : Output_data_plt_x86_64<size>(layout, plt_entry_size,
310 got, got_plt, got_irelative)
313 Output_data_plt_x86_64_standard(Layout* layout,
314 Output_data_got<64, false>* got,
315 Output_data_space* got_plt,
316 Output_data_space* got_irelative,
317 unsigned int plt_count)
318 : Output_data_plt_x86_64<size>(layout, plt_entry_size,
319 got, got_plt, got_irelative,
325 do_get_plt_entry_size() const
326 { return plt_entry_size; }
329 do_add_eh_frame(Layout* layout)
331 layout->add_eh_frame_for_plt(this,
332 this->plt_eh_frame_cie,
333 this->plt_eh_frame_cie_size,
335 plt_eh_frame_fde_size);
339 do_fill_first_plt_entry(unsigned char* pov,
340 typename elfcpp::Elf_types<size>::Elf_Addr got_addr,
341 typename elfcpp::Elf_types<size>::Elf_Addr plt_addr);
344 do_fill_plt_entry(unsigned char* pov,
345 typename elfcpp::Elf_types<size>::Elf_Addr got_address,
346 typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
347 unsigned int got_offset,
348 unsigned int plt_offset,
349 unsigned int plt_index);
352 do_fill_tlsdesc_entry(unsigned char* pov,
353 typename elfcpp::Elf_types<size>::Elf_Addr got_address,
354 typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
355 typename elfcpp::Elf_types<size>::Elf_Addr got_base,
356 unsigned int tlsdesc_got_offset,
357 unsigned int plt_offset);
360 // The size of an entry in the PLT.
361 static const int plt_entry_size = 16;
363 // The first entry in the PLT.
364 // From the AMD64 ABI: "Unlike Intel386 ABI, this ABI uses the same
365 // procedure linkage table for both programs and shared objects."
366 static const unsigned char first_plt_entry[plt_entry_size];
368 // Other entries in the PLT for an executable.
369 static const unsigned char plt_entry[plt_entry_size];
371 // The reserved TLSDESC entry in the PLT for an executable.
372 static const unsigned char tlsdesc_plt_entry[plt_entry_size];
374 // The .eh_frame unwind information for the PLT.
375 static const int plt_eh_frame_fde_size = 32;
376 static const unsigned char plt_eh_frame_fde[plt_eh_frame_fde_size];
379 // The x86_64 target class.
381 // http://www.x86-64.org/documentation/abi.pdf
382 // TLS info comes from
383 // http://people.redhat.com/drepper/tls.pdf
384 // http://www.lsd.ic.unicamp.br/~oliva/writeups/TLS/RFC-TLSDESC-x86.txt
387 class Target_x86_64 : public Sized_target<size, false>
390 // In the x86_64 ABI (p 68), it says "The AMD64 ABI architectures
391 // uses only Elf64_Rela relocation entries with explicit addends."
392 typedef Output_data_reloc<elfcpp::SHT_RELA, true, size, false> Reloc_section;
394 Target_x86_64(const Target::Target_info* info = &x86_64_info)
395 : Sized_target<size, false>(info),
396 got_(NULL), plt_(NULL), got_plt_(NULL), got_irelative_(NULL),
397 got_tlsdesc_(NULL), global_offset_table_(NULL), rela_dyn_(NULL),
398 rela_irelative_(NULL), copy_relocs_(elfcpp::R_X86_64_COPY),
399 dynbss_(NULL), got_mod_index_offset_(-1U), tlsdesc_reloc_info_(),
400 tls_base_symbol_defined_(false)
403 // Hook for a new output section.
405 do_new_output_section(Output_section*) const;
407 // Scan the relocations to look for symbol adjustments.
409 gc_process_relocs(Symbol_table* symtab,
411 Sized_relobj_file<size, false>* object,
412 unsigned int data_shndx,
413 unsigned int sh_type,
414 const unsigned char* prelocs,
416 Output_section* output_section,
417 bool needs_special_offset_handling,
418 size_t local_symbol_count,
419 const unsigned char* plocal_symbols);
421 // Scan the relocations to look for symbol adjustments.
423 scan_relocs(Symbol_table* symtab,
425 Sized_relobj_file<size, false>* object,
426 unsigned int data_shndx,
427 unsigned int sh_type,
428 const unsigned char* prelocs,
430 Output_section* output_section,
431 bool needs_special_offset_handling,
432 size_t local_symbol_count,
433 const unsigned char* plocal_symbols);
435 // Finalize the sections.
437 do_finalize_sections(Layout*, const Input_objects*, Symbol_table*);
439 // Return the value to use for a dynamic which requires special
442 do_dynsym_value(const Symbol*) const;
444 // Relocate a section.
446 relocate_section(const Relocate_info<size, false>*,
447 unsigned int sh_type,
448 const unsigned char* prelocs,
450 Output_section* output_section,
451 bool needs_special_offset_handling,
453 typename elfcpp::Elf_types<size>::Elf_Addr view_address,
454 section_size_type view_size,
455 const Reloc_symbol_changes*);
457 // Scan the relocs during a relocatable link.
459 scan_relocatable_relocs(Symbol_table* symtab,
461 Sized_relobj_file<size, false>* object,
462 unsigned int data_shndx,
463 unsigned int sh_type,
464 const unsigned char* prelocs,
466 Output_section* output_section,
467 bool needs_special_offset_handling,
468 size_t local_symbol_count,
469 const unsigned char* plocal_symbols,
470 Relocatable_relocs*);
472 // Relocate a section during a relocatable link.
474 relocate_for_relocatable(
475 const Relocate_info<size, false>*,
476 unsigned int sh_type,
477 const unsigned char* prelocs,
479 Output_section* output_section,
480 off_t offset_in_output_section,
481 const Relocatable_relocs*,
483 typename elfcpp::Elf_types<size>::Elf_Addr view_address,
484 section_size_type view_size,
485 unsigned char* reloc_view,
486 section_size_type reloc_view_size);
488 // Return a string used to fill a code section with nops.
490 do_code_fill(section_size_type length) const;
492 // Return whether SYM is defined by the ABI.
494 do_is_defined_by_abi(const Symbol* sym) const
495 { return strcmp(sym->name(), "__tls_get_addr") == 0; }
497 // Return the symbol index to use for a target specific relocation.
498 // The only target specific relocation is R_X86_64_TLSDESC for a
499 // local symbol, which is an absolute reloc.
501 do_reloc_symbol_index(void*, unsigned int r_type) const
503 gold_assert(r_type == elfcpp::R_X86_64_TLSDESC);
507 // Return the addend to use for a target specific relocation.
509 do_reloc_addend(void* arg, unsigned int r_type, uint64_t addend) const;
511 // Return the PLT section.
513 do_plt_address_for_global(const Symbol* gsym) const
514 { return this->plt_section()->address_for_global(gsym); }
517 do_plt_address_for_local(const Relobj* relobj, unsigned int symndx) const
518 { return this->plt_section()->address_for_local(relobj, symndx); }
520 // This function should be defined in targets that can use relocation
521 // types to determine (implemented in local_reloc_may_be_function_pointer
522 // and global_reloc_may_be_function_pointer)
523 // if a function's pointer is taken. ICF uses this in safe mode to only
524 // fold those functions whose pointer is defintely not taken. For x86_64
525 // pie binaries, safe ICF cannot be done by looking at relocation types.
527 do_can_check_for_function_pointers() const
528 { return !parameters->options().pie(); }
530 // Return the base for a DW_EH_PE_datarel encoding.
532 do_ehframe_datarel_base() const;
534 // Adjust -fsplit-stack code which calls non-split-stack code.
536 do_calls_non_split(Relobj* object, unsigned int shndx,
537 section_offset_type fnoffset, section_size_type fnsize,
538 unsigned char* view, section_size_type view_size,
539 std::string* from, std::string* to) const;
541 // Return the size of the GOT section.
545 gold_assert(this->got_ != NULL);
546 return this->got_->data_size();
549 // Return the number of entries in the GOT.
551 got_entry_count() const
553 if (this->got_ == NULL)
555 return this->got_size() / 8;
558 // Return the number of entries in the PLT.
560 plt_entry_count() const;
562 // Return the offset of the first non-reserved PLT entry.
564 first_plt_entry_offset() const;
566 // Return the size of each PLT entry.
568 plt_entry_size() const;
570 // Create the GOT section for an incremental update.
571 Output_data_got_base*
572 init_got_plt_for_update(Symbol_table* symtab,
574 unsigned int got_count,
575 unsigned int plt_count);
577 // Reserve a GOT entry for a local symbol, and regenerate any
578 // necessary dynamic relocations.
580 reserve_local_got_entry(unsigned int got_index,
581 Sized_relobj<size, false>* obj,
583 unsigned int got_type);
585 // Reserve a GOT entry for a global symbol, and regenerate any
586 // necessary dynamic relocations.
588 reserve_global_got_entry(unsigned int got_index, Symbol* gsym,
589 unsigned int got_type);
591 // Register an existing PLT entry for a global symbol.
593 register_global_plt_entry(Symbol_table*, Layout*, unsigned int plt_index,
596 // Force a COPY relocation for a given symbol.
598 emit_copy_reloc(Symbol_table*, Symbol*, Output_section*, off_t);
600 // Apply an incremental relocation.
602 apply_relocation(const Relocate_info<size, false>* relinfo,
603 typename elfcpp::Elf_types<size>::Elf_Addr r_offset,
605 typename elfcpp::Elf_types<size>::Elf_Swxword r_addend,
608 typename elfcpp::Elf_types<size>::Elf_Addr address,
609 section_size_type view_size);
611 // Add a new reloc argument, returning the index in the vector.
613 add_tlsdesc_info(Sized_relobj_file<size, false>* object, unsigned int r_sym)
615 this->tlsdesc_reloc_info_.push_back(Tlsdesc_info(object, r_sym));
616 return this->tlsdesc_reloc_info_.size() - 1;
619 Output_data_plt_x86_64<size>*
620 make_data_plt(Layout* layout,
621 Output_data_got<64, false>* got,
622 Output_data_space* got_plt,
623 Output_data_space* got_irelative)
625 return this->do_make_data_plt(layout, got, got_plt, got_irelative);
628 Output_data_plt_x86_64<size>*
629 make_data_plt(Layout* layout,
630 Output_data_got<64, false>* got,
631 Output_data_space* got_plt,
632 Output_data_space* got_irelative,
633 unsigned int plt_count)
635 return this->do_make_data_plt(layout, got, got_plt, got_irelative,
639 virtual Output_data_plt_x86_64<size>*
640 do_make_data_plt(Layout* layout,
641 Output_data_got<64, false>* got,
642 Output_data_space* got_plt,
643 Output_data_space* got_irelative)
645 return new Output_data_plt_x86_64_standard<size>(layout, got, got_plt,
649 virtual Output_data_plt_x86_64<size>*
650 do_make_data_plt(Layout* layout,
651 Output_data_got<64, false>* got,
652 Output_data_space* got_plt,
653 Output_data_space* got_irelative,
654 unsigned int plt_count)
656 return new Output_data_plt_x86_64_standard<size>(layout, got, got_plt,
662 // The class which scans relocations.
667 : issued_non_pic_error_(false)
671 get_reference_flags(unsigned int r_type);
674 local(Symbol_table* symtab, Layout* layout, Target_x86_64* target,
675 Sized_relobj_file<size, false>* object,
676 unsigned int data_shndx,
677 Output_section* output_section,
678 const elfcpp::Rela<size, false>& reloc, unsigned int r_type,
679 const elfcpp::Sym<size, false>& lsym);
682 global(Symbol_table* symtab, Layout* layout, Target_x86_64* target,
683 Sized_relobj_file<size, false>* object,
684 unsigned int data_shndx,
685 Output_section* output_section,
686 const elfcpp::Rela<size, false>& reloc, unsigned int r_type,
690 local_reloc_may_be_function_pointer(Symbol_table* symtab, Layout* layout,
691 Target_x86_64* target,
692 Sized_relobj_file<size, false>* object,
693 unsigned int data_shndx,
694 Output_section* output_section,
695 const elfcpp::Rela<size, false>& reloc,
697 const elfcpp::Sym<size, false>& lsym);
700 global_reloc_may_be_function_pointer(Symbol_table* symtab, Layout* layout,
701 Target_x86_64* target,
702 Sized_relobj_file<size, false>* object,
703 unsigned int data_shndx,
704 Output_section* output_section,
705 const elfcpp::Rela<size, false>& reloc,
711 unsupported_reloc_local(Sized_relobj_file<size, false>*,
712 unsigned int r_type);
715 unsupported_reloc_global(Sized_relobj_file<size, false>*,
716 unsigned int r_type, Symbol*);
719 check_non_pic(Relobj*, unsigned int r_type, Symbol*);
722 possible_function_pointer_reloc(unsigned int r_type);
725 reloc_needs_plt_for_ifunc(Sized_relobj_file<size, false>*,
726 unsigned int r_type);
728 // Whether we have issued an error about a non-PIC compilation.
729 bool issued_non_pic_error_;
732 // The class which implements relocation.
737 : skip_call_tls_get_addr_(false)
742 if (this->skip_call_tls_get_addr_)
744 // FIXME: This needs to specify the location somehow.
745 gold_error(_("missing expected TLS relocation"));
749 // Do a relocation. Return false if the caller should not issue
750 // any warnings about this relocation.
752 relocate(const Relocate_info<size, false>*, Target_x86_64*,
754 size_t relnum, const elfcpp::Rela<size, false>&,
755 unsigned int r_type, const Sized_symbol<size>*,
756 const Symbol_value<size>*,
757 unsigned char*, typename elfcpp::Elf_types<size>::Elf_Addr,
761 // Do a TLS relocation.
763 relocate_tls(const Relocate_info<size, false>*, Target_x86_64*,
764 size_t relnum, const elfcpp::Rela<size, false>&,
765 unsigned int r_type, const Sized_symbol<size>*,
766 const Symbol_value<size>*,
767 unsigned char*, typename elfcpp::Elf_types<size>::Elf_Addr,
770 // Do a TLS General-Dynamic to Initial-Exec transition.
772 tls_gd_to_ie(const Relocate_info<size, false>*, size_t relnum,
773 Output_segment* tls_segment,
774 const elfcpp::Rela<size, false>&, unsigned int r_type,
775 typename elfcpp::Elf_types<size>::Elf_Addr value,
777 typename elfcpp::Elf_types<size>::Elf_Addr,
778 section_size_type view_size);
780 // Do a TLS General-Dynamic to Local-Exec transition.
782 tls_gd_to_le(const Relocate_info<size, false>*, size_t relnum,
783 Output_segment* tls_segment,
784 const elfcpp::Rela<size, false>&, unsigned int r_type,
785 typename elfcpp::Elf_types<size>::Elf_Addr value,
787 section_size_type view_size);
789 // Do a TLSDESC-style General-Dynamic to Initial-Exec transition.
791 tls_desc_gd_to_ie(const Relocate_info<size, false>*, size_t relnum,
792 Output_segment* tls_segment,
793 const elfcpp::Rela<size, false>&, unsigned int r_type,
794 typename elfcpp::Elf_types<size>::Elf_Addr value,
796 typename elfcpp::Elf_types<size>::Elf_Addr,
797 section_size_type view_size);
799 // Do a TLSDESC-style General-Dynamic to Local-Exec transition.
801 tls_desc_gd_to_le(const Relocate_info<size, false>*, size_t relnum,
802 Output_segment* tls_segment,
803 const elfcpp::Rela<size, false>&, unsigned int r_type,
804 typename elfcpp::Elf_types<size>::Elf_Addr value,
806 section_size_type view_size);
808 // Do a TLS Local-Dynamic to Local-Exec transition.
810 tls_ld_to_le(const Relocate_info<size, false>*, size_t relnum,
811 Output_segment* tls_segment,
812 const elfcpp::Rela<size, false>&, unsigned int r_type,
813 typename elfcpp::Elf_types<size>::Elf_Addr value,
815 section_size_type view_size);
817 // Do a TLS Initial-Exec to Local-Exec transition.
819 tls_ie_to_le(const Relocate_info<size, false>*, size_t relnum,
820 Output_segment* tls_segment,
821 const elfcpp::Rela<size, false>&, unsigned int r_type,
822 typename elfcpp::Elf_types<size>::Elf_Addr value,
824 section_size_type view_size);
826 // This is set if we should skip the next reloc, which should be a
827 // PLT32 reloc against ___tls_get_addr.
828 bool skip_call_tls_get_addr_;
831 // A class which returns the size required for a relocation type,
832 // used while scanning relocs during a relocatable link.
833 class Relocatable_size_for_reloc
837 get_size_for_reloc(unsigned int, Relobj*);
840 // Adjust TLS relocation type based on the options and whether this
841 // is a local symbol.
842 static tls::Tls_optimization
843 optimize_tls_reloc(bool is_final, int r_type);
845 // Get the GOT section, creating it if necessary.
846 Output_data_got<64, false>*
847 got_section(Symbol_table*, Layout*);
849 // Get the GOT PLT section.
851 got_plt_section() const
853 gold_assert(this->got_plt_ != NULL);
854 return this->got_plt_;
857 // Get the GOT section for TLSDESC entries.
858 Output_data_got<64, false>*
859 got_tlsdesc_section() const
861 gold_assert(this->got_tlsdesc_ != NULL);
862 return this->got_tlsdesc_;
865 // Create the PLT section.
867 make_plt_section(Symbol_table* symtab, Layout* layout);
869 // Create a PLT entry for a global symbol.
871 make_plt_entry(Symbol_table*, Layout*, Symbol*);
873 // Create a PLT entry for a local STT_GNU_IFUNC symbol.
875 make_local_ifunc_plt_entry(Symbol_table*, Layout*,
876 Sized_relobj_file<size, false>* relobj,
877 unsigned int local_sym_index);
879 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
881 define_tls_base_symbol(Symbol_table*, Layout*);
883 // Create the reserved PLT and GOT entries for the TLS descriptor resolver.
885 reserve_tlsdesc_entries(Symbol_table* symtab, Layout* layout);
887 // Create a GOT entry for the TLS module index.
889 got_mod_index_entry(Symbol_table* symtab, Layout* layout,
890 Sized_relobj_file<size, false>* object);
892 // Get the PLT section.
893 Output_data_plt_x86_64<size>*
896 gold_assert(this->plt_ != NULL);
900 // Get the dynamic reloc section, creating it if necessary.
902 rela_dyn_section(Layout*);
904 // Get the section to use for TLSDESC relocations.
906 rela_tlsdesc_section(Layout*) const;
908 // Get the section to use for IRELATIVE relocations.
910 rela_irelative_section(Layout*);
912 // Add a potential copy relocation.
914 copy_reloc(Symbol_table* symtab, Layout* layout,
915 Sized_relobj_file<size, false>* object,
916 unsigned int shndx, Output_section* output_section,
917 Symbol* sym, const elfcpp::Rela<size, false>& reloc)
919 this->copy_relocs_.copy_reloc(symtab, layout,
920 symtab->get_sized_symbol<size>(sym),
921 object, shndx, output_section,
922 reloc, this->rela_dyn_section(layout));
925 // Information about this specific target which we pass to the
926 // general Target structure.
927 static const Target::Target_info x86_64_info;
929 // The types of GOT entries needed for this platform.
930 // These values are exposed to the ABI in an incremental link.
931 // Do not renumber existing values without changing the version
932 // number of the .gnu_incremental_inputs section.
935 GOT_TYPE_STANDARD = 0, // GOT entry for a regular symbol
936 GOT_TYPE_TLS_OFFSET = 1, // GOT entry for TLS offset
937 GOT_TYPE_TLS_PAIR = 2, // GOT entry for TLS module/offset pair
938 GOT_TYPE_TLS_DESC = 3 // GOT entry for TLS_DESC pair
941 // This type is used as the argument to the target specific
942 // relocation routines. The only target specific reloc is
943 // R_X86_64_TLSDESC against a local symbol.
946 Tlsdesc_info(Sized_relobj_file<size, false>* a_object, unsigned int a_r_sym)
947 : object(a_object), r_sym(a_r_sym)
950 // The object in which the local symbol is defined.
951 Sized_relobj_file<size, false>* object;
952 // The local symbol index in the object.
957 Output_data_got<64, false>* got_;
959 Output_data_plt_x86_64<size>* plt_;
960 // The GOT PLT section.
961 Output_data_space* got_plt_;
962 // The GOT section for IRELATIVE relocations.
963 Output_data_space* got_irelative_;
964 // The GOT section for TLSDESC relocations.
965 Output_data_got<64, false>* got_tlsdesc_;
966 // The _GLOBAL_OFFSET_TABLE_ symbol.
967 Symbol* global_offset_table_;
968 // The dynamic reloc section.
969 Reloc_section* rela_dyn_;
970 // The section to use for IRELATIVE relocs.
971 Reloc_section* rela_irelative_;
972 // Relocs saved to avoid a COPY reloc.
973 Copy_relocs<elfcpp::SHT_RELA, size, false> copy_relocs_;
974 // Space for variables copied with a COPY reloc.
975 Output_data_space* dynbss_;
976 // Offset of the GOT entry for the TLS module index.
977 unsigned int got_mod_index_offset_;
978 // We handle R_X86_64_TLSDESC against a local symbol as a target
979 // specific relocation. Here we store the object and local symbol
980 // index for the relocation.
981 std::vector<Tlsdesc_info> tlsdesc_reloc_info_;
982 // True if the _TLS_MODULE_BASE_ symbol has been defined.
983 bool tls_base_symbol_defined_;
987 const Target::Target_info Target_x86_64<64>::x86_64_info =
990 false, // is_big_endian
991 elfcpp::EM_X86_64, // machine_code
992 false, // has_make_symbol
993 false, // has_resolve
994 true, // has_code_fill
995 true, // is_default_stack_executable
996 true, // can_icf_inline_merge_sections
998 "/lib/ld64.so.1", // program interpreter
999 0x400000, // default_text_segment_address
1000 0x1000, // abi_pagesize (overridable by -z max-page-size)
1001 0x1000, // common_pagesize (overridable by -z common-page-size)
1002 false, // isolate_execinstr
1004 elfcpp::SHN_UNDEF, // small_common_shndx
1005 elfcpp::SHN_X86_64_LCOMMON, // large_common_shndx
1006 0, // small_common_section_flags
1007 elfcpp::SHF_X86_64_LARGE, // large_common_section_flags
1008 NULL, // attributes_section
1009 NULL // attributes_vendor
1013 const Target::Target_info Target_x86_64<32>::x86_64_info =
1016 false, // is_big_endian
1017 elfcpp::EM_X86_64, // machine_code
1018 false, // has_make_symbol
1019 false, // has_resolve
1020 true, // has_code_fill
1021 true, // is_default_stack_executable
1022 true, // can_icf_inline_merge_sections
1024 "/libx32/ldx32.so.1", // program interpreter
1025 0x400000, // default_text_segment_address
1026 0x1000, // abi_pagesize (overridable by -z max-page-size)
1027 0x1000, // common_pagesize (overridable by -z common-page-size)
1028 false, // isolate_execinstr
1030 elfcpp::SHN_UNDEF, // small_common_shndx
1031 elfcpp::SHN_X86_64_LCOMMON, // large_common_shndx
1032 0, // small_common_section_flags
1033 elfcpp::SHF_X86_64_LARGE, // large_common_section_flags
1034 NULL, // attributes_section
1035 NULL // attributes_vendor
1038 // This is called when a new output section is created. This is where
1039 // we handle the SHF_X86_64_LARGE.
1043 Target_x86_64<size>::do_new_output_section(Output_section* os) const
1045 if ((os->flags() & elfcpp::SHF_X86_64_LARGE) != 0)
1046 os->set_is_large_section();
1049 // Get the GOT section, creating it if necessary.
1052 Output_data_got<64, false>*
1053 Target_x86_64<size>::got_section(Symbol_table* symtab, Layout* layout)
1055 if (this->got_ == NULL)
1057 gold_assert(symtab != NULL && layout != NULL);
1059 // When using -z now, we can treat .got.plt as a relro section.
1060 // Without -z now, it is modified after program startup by lazy
1062 bool is_got_plt_relro = parameters->options().now();
1063 Output_section_order got_order = (is_got_plt_relro
1065 : ORDER_RELRO_LAST);
1066 Output_section_order got_plt_order = (is_got_plt_relro
1068 : ORDER_NON_RELRO_FIRST);
1070 this->got_ = new Output_data_got<64, false>();
1072 layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
1074 | elfcpp::SHF_WRITE),
1075 this->got_, got_order, true);
1077 this->got_plt_ = new Output_data_space(8, "** GOT PLT");
1078 layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
1080 | elfcpp::SHF_WRITE),
1081 this->got_plt_, got_plt_order,
1084 // The first three entries are reserved.
1085 this->got_plt_->set_current_data_size(3 * 8);
1087 if (!is_got_plt_relro)
1089 // Those bytes can go into the relro segment.
1090 layout->increase_relro(3 * 8);
1093 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
1094 this->global_offset_table_ =
1095 symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
1096 Symbol_table::PREDEFINED,
1098 0, 0, elfcpp::STT_OBJECT,
1100 elfcpp::STV_HIDDEN, 0,
1103 // If there are any IRELATIVE relocations, they get GOT entries
1104 // in .got.plt after the jump slot entries.
1105 this->got_irelative_ = new Output_data_space(8, "** GOT IRELATIVE PLT");
1106 layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
1108 | elfcpp::SHF_WRITE),
1109 this->got_irelative_,
1110 got_plt_order, is_got_plt_relro);
1112 // If there are any TLSDESC relocations, they get GOT entries in
1113 // .got.plt after the jump slot and IRELATIVE entries.
1114 this->got_tlsdesc_ = new Output_data_got<64, false>();
1115 layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
1117 | elfcpp::SHF_WRITE),
1119 got_plt_order, is_got_plt_relro);
1125 // Get the dynamic reloc section, creating it if necessary.
1128 typename Target_x86_64<size>::Reloc_section*
1129 Target_x86_64<size>::rela_dyn_section(Layout* layout)
1131 if (this->rela_dyn_ == NULL)
1133 gold_assert(layout != NULL);
1134 this->rela_dyn_ = new Reloc_section(parameters->options().combreloc());
1135 layout->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA,
1136 elfcpp::SHF_ALLOC, this->rela_dyn_,
1137 ORDER_DYNAMIC_RELOCS, false);
1139 return this->rela_dyn_;
1142 // Get the section to use for IRELATIVE relocs, creating it if
1143 // necessary. These go in .rela.dyn, but only after all other dynamic
1144 // relocations. They need to follow the other dynamic relocations so
1145 // that they can refer to global variables initialized by those
1149 typename Target_x86_64<size>::Reloc_section*
1150 Target_x86_64<size>::rela_irelative_section(Layout* layout)
1152 if (this->rela_irelative_ == NULL)
1154 // Make sure we have already created the dynamic reloc section.
1155 this->rela_dyn_section(layout);
1156 this->rela_irelative_ = new Reloc_section(false);
1157 layout->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA,
1158 elfcpp::SHF_ALLOC, this->rela_irelative_,
1159 ORDER_DYNAMIC_RELOCS, false);
1160 gold_assert(this->rela_dyn_->output_section()
1161 == this->rela_irelative_->output_section());
1163 return this->rela_irelative_;
1166 // Initialize the PLT section.
1170 Output_data_plt_x86_64<size>::init(Layout* layout)
1172 this->rel_ = new Reloc_section(false);
1173 layout->add_output_section_data(".rela.plt", elfcpp::SHT_RELA,
1174 elfcpp::SHF_ALLOC, this->rel_,
1175 ORDER_DYNAMIC_PLT_RELOCS, false);
1180 Output_data_plt_x86_64<size>::do_adjust_output_section(Output_section* os)
1182 os->set_entsize(this->get_plt_entry_size());
1185 // Add an entry to the PLT.
1189 Output_data_plt_x86_64<size>::add_entry(Symbol_table* symtab, Layout* layout,
1192 gold_assert(!gsym->has_plt_offset());
1194 unsigned int plt_index;
1196 section_offset_type got_offset;
1198 unsigned int* pcount;
1199 unsigned int offset;
1200 unsigned int reserved;
1201 Output_data_space* got;
1202 if (gsym->type() == elfcpp::STT_GNU_IFUNC
1203 && gsym->can_use_relative_reloc(false))
1205 pcount = &this->irelative_count_;
1208 got = this->got_irelative_;
1212 pcount = &this->count_;
1215 got = this->got_plt_;
1218 if (!this->is_data_size_valid())
1220 // Note that when setting the PLT offset for a non-IRELATIVE
1221 // entry we skip the initial reserved PLT entry.
1222 plt_index = *pcount + offset;
1223 plt_offset = plt_index * this->get_plt_entry_size();
1227 got_offset = (plt_index - offset + reserved) * 8;
1228 gold_assert(got_offset == got->current_data_size());
1230 // Every PLT entry needs a GOT entry which points back to the PLT
1231 // entry (this will be changed by the dynamic linker, normally
1232 // lazily when the function is called).
1233 got->set_current_data_size(got_offset + 8);
1237 // FIXME: This is probably not correct for IRELATIVE relocs.
1239 // For incremental updates, find an available slot.
1240 plt_offset = this->free_list_.allocate(this->get_plt_entry_size(),
1241 this->get_plt_entry_size(), 0);
1242 if (plt_offset == -1)
1243 gold_fallback(_("out of patch space (PLT);"
1244 " relink with --incremental-full"));
1246 // The GOT and PLT entries have a 1-1 correspondance, so the GOT offset
1247 // can be calculated from the PLT index, adjusting for the three
1248 // reserved entries at the beginning of the GOT.
1249 plt_index = plt_offset / this->get_plt_entry_size() - 1;
1250 got_offset = (plt_index - offset + reserved) * 8;
1253 gsym->set_plt_offset(plt_offset);
1255 // Every PLT entry needs a reloc.
1256 this->add_relocation(symtab, layout, gsym, got_offset);
1258 // Note that we don't need to save the symbol. The contents of the
1259 // PLT are independent of which symbols are used. The symbols only
1260 // appear in the relocations.
1263 // Add an entry to the PLT for a local STT_GNU_IFUNC symbol. Return
1268 Output_data_plt_x86_64<size>::add_local_ifunc_entry(
1269 Symbol_table* symtab,
1271 Sized_relobj_file<size, false>* relobj,
1272 unsigned int local_sym_index)
1274 unsigned int plt_offset = this->irelative_count_ * this->get_plt_entry_size();
1275 ++this->irelative_count_;
1277 section_offset_type got_offset = this->got_irelative_->current_data_size();
1279 // Every PLT entry needs a GOT entry which points back to the PLT
1281 this->got_irelative_->set_current_data_size(got_offset + 8);
1283 // Every PLT entry needs a reloc.
1284 Reloc_section* rela = this->rela_irelative(symtab, layout);
1285 rela->add_symbolless_local_addend(relobj, local_sym_index,
1286 elfcpp::R_X86_64_IRELATIVE,
1287 this->got_irelative_, got_offset, 0);
1292 // Add the relocation for a PLT entry.
1296 Output_data_plt_x86_64<size>::add_relocation(Symbol_table* symtab,
1299 unsigned int got_offset)
1301 if (gsym->type() == elfcpp::STT_GNU_IFUNC
1302 && gsym->can_use_relative_reloc(false))
1304 Reloc_section* rela = this->rela_irelative(symtab, layout);
1305 rela->add_symbolless_global_addend(gsym, elfcpp::R_X86_64_IRELATIVE,
1306 this->got_irelative_, got_offset, 0);
1310 gsym->set_needs_dynsym_entry();
1311 this->rel_->add_global(gsym, elfcpp::R_X86_64_JUMP_SLOT, this->got_plt_,
1316 // Return where the TLSDESC relocations should go, creating it if
1317 // necessary. These follow the JUMP_SLOT relocations.
1320 typename Output_data_plt_x86_64<size>::Reloc_section*
1321 Output_data_plt_x86_64<size>::rela_tlsdesc(Layout* layout)
1323 if (this->tlsdesc_rel_ == NULL)
1325 this->tlsdesc_rel_ = new Reloc_section(false);
1326 layout->add_output_section_data(".rela.plt", elfcpp::SHT_RELA,
1327 elfcpp::SHF_ALLOC, this->tlsdesc_rel_,
1328 ORDER_DYNAMIC_PLT_RELOCS, false);
1329 gold_assert(this->tlsdesc_rel_->output_section()
1330 == this->rel_->output_section());
1332 return this->tlsdesc_rel_;
1335 // Return where the IRELATIVE relocations should go in the PLT. These
1336 // follow the JUMP_SLOT and the TLSDESC relocations.
1339 typename Output_data_plt_x86_64<size>::Reloc_section*
1340 Output_data_plt_x86_64<size>::rela_irelative(Symbol_table* symtab,
1343 if (this->irelative_rel_ == NULL)
1345 // Make sure we have a place for the TLSDESC relocations, in
1346 // case we see any later on.
1347 this->rela_tlsdesc(layout);
1348 this->irelative_rel_ = new Reloc_section(false);
1349 layout->add_output_section_data(".rela.plt", elfcpp::SHT_RELA,
1350 elfcpp::SHF_ALLOC, this->irelative_rel_,
1351 ORDER_DYNAMIC_PLT_RELOCS, false);
1352 gold_assert(this->irelative_rel_->output_section()
1353 == this->rel_->output_section());
1355 if (parameters->doing_static_link())
1357 // A statically linked executable will only have a .rela.plt
1358 // section to hold R_X86_64_IRELATIVE relocs for
1359 // STT_GNU_IFUNC symbols. The library will use these
1360 // symbols to locate the IRELATIVE relocs at program startup
1362 symtab->define_in_output_data("__rela_iplt_start", NULL,
1363 Symbol_table::PREDEFINED,
1364 this->irelative_rel_, 0, 0,
1365 elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL,
1366 elfcpp::STV_HIDDEN, 0, false, true);
1367 symtab->define_in_output_data("__rela_iplt_end", NULL,
1368 Symbol_table::PREDEFINED,
1369 this->irelative_rel_, 0, 0,
1370 elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL,
1371 elfcpp::STV_HIDDEN, 0, true, true);
1374 return this->irelative_rel_;
1377 // Return the PLT address to use for a global symbol.
1381 Output_data_plt_x86_64<size>::address_for_global(const Symbol* gsym)
1383 uint64_t offset = 0;
1384 if (gsym->type() == elfcpp::STT_GNU_IFUNC
1385 && gsym->can_use_relative_reloc(false))
1386 offset = (this->count_ + 1) * this->get_plt_entry_size();
1387 return this->address() + offset;
1390 // Return the PLT address to use for a local symbol. These are always
1391 // IRELATIVE relocs.
1395 Output_data_plt_x86_64<size>::address_for_local(const Relobj*, unsigned int)
1397 return this->address() + (this->count_ + 1) * this->get_plt_entry_size();
1400 // Set the final size.
1403 Output_data_plt_x86_64<size>::set_final_data_size()
1405 unsigned int count = this->count_ + this->irelative_count_;
1406 if (this->has_tlsdesc_entry())
1408 this->set_data_size((count + 1) * this->get_plt_entry_size());
1411 // The first entry in the PLT for an executable.
1415 Output_data_plt_x86_64_standard<size>::first_plt_entry[plt_entry_size] =
1417 // From AMD64 ABI Draft 0.98, page 76
1418 0xff, 0x35, // pushq contents of memory address
1419 0, 0, 0, 0, // replaced with address of .got + 8
1420 0xff, 0x25, // jmp indirect
1421 0, 0, 0, 0, // replaced with address of .got + 16
1422 0x90, 0x90, 0x90, 0x90 // noop (x4)
1427 Output_data_plt_x86_64_standard<size>::do_fill_first_plt_entry(
1429 typename elfcpp::Elf_types<size>::Elf_Addr got_address,
1430 typename elfcpp::Elf_types<size>::Elf_Addr plt_address)
1432 memcpy(pov, first_plt_entry, plt_entry_size);
1433 // We do a jmp relative to the PC at the end of this instruction.
1434 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
1436 - (plt_address + 6)));
1437 elfcpp::Swap<32, false>::writeval(pov + 8,
1439 - (plt_address + 12)));
1442 // Subsequent entries in the PLT for an executable.
1446 Output_data_plt_x86_64_standard<size>::plt_entry[plt_entry_size] =
1448 // From AMD64 ABI Draft 0.98, page 76
1449 0xff, 0x25, // jmpq indirect
1450 0, 0, 0, 0, // replaced with address of symbol in .got
1451 0x68, // pushq immediate
1452 0, 0, 0, 0, // replaced with offset into relocation table
1453 0xe9, // jmpq relative
1454 0, 0, 0, 0 // replaced with offset to start of .plt
1459 Output_data_plt_x86_64_standard<size>::do_fill_plt_entry(
1461 typename elfcpp::Elf_types<size>::Elf_Addr got_address,
1462 typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
1463 unsigned int got_offset,
1464 unsigned int plt_offset,
1465 unsigned int plt_index)
1467 memcpy(pov, plt_entry, plt_entry_size);
1468 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
1469 (got_address + got_offset
1470 - (plt_address + plt_offset
1473 elfcpp::Swap_unaligned<32, false>::writeval(pov + 7, plt_index);
1474 elfcpp::Swap<32, false>::writeval(pov + 12,
1475 - (plt_offset + plt_entry_size));
1480 // The reserved TLSDESC entry in the PLT for an executable.
1484 Output_data_plt_x86_64_standard<size>::tlsdesc_plt_entry[plt_entry_size] =
1486 // From Alexandre Oliva, "Thread-Local Storage Descriptors for IA32
1487 // and AMD64/EM64T", Version 0.9.4 (2005-10-10).
1488 0xff, 0x35, // pushq x(%rip)
1489 0, 0, 0, 0, // replaced with address of linkmap GOT entry (at PLTGOT + 8)
1490 0xff, 0x25, // jmpq *y(%rip)
1491 0, 0, 0, 0, // replaced with offset of reserved TLSDESC_GOT entry
1498 Output_data_plt_x86_64_standard<size>::do_fill_tlsdesc_entry(
1500 typename elfcpp::Elf_types<size>::Elf_Addr got_address,
1501 typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
1502 typename elfcpp::Elf_types<size>::Elf_Addr got_base,
1503 unsigned int tlsdesc_got_offset,
1504 unsigned int plt_offset)
1506 memcpy(pov, tlsdesc_plt_entry, plt_entry_size);
1507 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
1509 - (plt_address + plt_offset
1511 elfcpp::Swap_unaligned<32, false>::writeval(pov + 8,
1513 + tlsdesc_got_offset
1514 - (plt_address + plt_offset
1518 // The .eh_frame unwind information for the PLT.
1522 Output_data_plt_x86_64<size>::plt_eh_frame_cie[plt_eh_frame_cie_size] =
1525 'z', // Augmentation: augmentation size included.
1526 'R', // Augmentation: FDE encoding included.
1527 '\0', // End of augmentation string.
1528 1, // Code alignment factor.
1529 0x78, // Data alignment factor.
1530 16, // Return address column.
1531 1, // Augmentation size.
1532 (elfcpp::DW_EH_PE_pcrel // FDE encoding.
1533 | elfcpp::DW_EH_PE_sdata4),
1534 elfcpp::DW_CFA_def_cfa, 7, 8, // DW_CFA_def_cfa: r7 (rsp) ofs 8.
1535 elfcpp::DW_CFA_offset + 16, 1,// DW_CFA_offset: r16 (rip) at cfa-8.
1536 elfcpp::DW_CFA_nop, // Align to 16 bytes.
1542 Output_data_plt_x86_64_standard<size>::plt_eh_frame_fde[plt_eh_frame_fde_size] =
1544 0, 0, 0, 0, // Replaced with offset to .plt.
1545 0, 0, 0, 0, // Replaced with size of .plt.
1546 0, // Augmentation size.
1547 elfcpp::DW_CFA_def_cfa_offset, 16, // DW_CFA_def_cfa_offset: 16.
1548 elfcpp::DW_CFA_advance_loc + 6, // Advance 6 to __PLT__ + 6.
1549 elfcpp::DW_CFA_def_cfa_offset, 24, // DW_CFA_def_cfa_offset: 24.
1550 elfcpp::DW_CFA_advance_loc + 10, // Advance 10 to __PLT__ + 16.
1551 elfcpp::DW_CFA_def_cfa_expression, // DW_CFA_def_cfa_expression.
1552 11, // Block length.
1553 elfcpp::DW_OP_breg7, 8, // Push %rsp + 8.
1554 elfcpp::DW_OP_breg16, 0, // Push %rip.
1555 elfcpp::DW_OP_lit15, // Push 0xf.
1556 elfcpp::DW_OP_and, // & (%rip & 0xf).
1557 elfcpp::DW_OP_lit11, // Push 0xb.
1558 elfcpp::DW_OP_ge, // >= ((%rip & 0xf) >= 0xb)
1559 elfcpp::DW_OP_lit3, // Push 3.
1560 elfcpp::DW_OP_shl, // << (((%rip & 0xf) >= 0xb) << 3)
1561 elfcpp::DW_OP_plus, // + ((((%rip&0xf)>=0xb)<<3)+%rsp+8
1562 elfcpp::DW_CFA_nop, // Align to 32 bytes.
1568 // Write out the PLT. This uses the hand-coded instructions above,
1569 // and adjusts them as needed. This is specified by the AMD64 ABI.
1573 Output_data_plt_x86_64<size>::do_write(Output_file* of)
1575 const off_t offset = this->offset();
1576 const section_size_type oview_size =
1577 convert_to_section_size_type(this->data_size());
1578 unsigned char* const oview = of->get_output_view(offset, oview_size);
1580 const off_t got_file_offset = this->got_plt_->offset();
1581 gold_assert(parameters->incremental_update()
1582 || (got_file_offset + this->got_plt_->data_size()
1583 == this->got_irelative_->offset()));
1584 const section_size_type got_size =
1585 convert_to_section_size_type(this->got_plt_->data_size()
1586 + this->got_irelative_->data_size());
1587 unsigned char* const got_view = of->get_output_view(got_file_offset,
1590 unsigned char* pov = oview;
1592 // The base address of the .plt section.
1593 typename elfcpp::Elf_types<size>::Elf_Addr plt_address = this->address();
1594 // The base address of the .got section.
1595 typename elfcpp::Elf_types<size>::Elf_Addr got_base = this->got_->address();
1596 // The base address of the PLT portion of the .got section,
1597 // which is where the GOT pointer will point, and where the
1598 // three reserved GOT entries are located.
1599 typename elfcpp::Elf_types<size>::Elf_Addr got_address
1600 = this->got_plt_->address();
1602 this->fill_first_plt_entry(pov, got_address, plt_address);
1603 pov += this->get_plt_entry_size();
1605 unsigned char* got_pov = got_view;
1607 // The first entry in the GOT is the address of the .dynamic section
1608 // aka the PT_DYNAMIC segment. The next two entries are reserved.
1609 // We saved space for them when we created the section in
1610 // Target_x86_64::got_section.
1611 Output_section* dynamic = this->layout_->dynamic_section();
1612 uint32_t dynamic_addr = dynamic == NULL ? 0 : dynamic->address();
1613 elfcpp::Swap<64, false>::writeval(got_pov, dynamic_addr);
1615 memset(got_pov, 0, 16);
1618 unsigned int plt_offset = this->get_plt_entry_size();
1619 unsigned int got_offset = 24;
1620 const unsigned int count = this->count_ + this->irelative_count_;
1621 for (unsigned int plt_index = 0;
1624 pov += this->get_plt_entry_size(),
1626 plt_offset += this->get_plt_entry_size(),
1629 // Set and adjust the PLT entry itself.
1630 unsigned int lazy_offset = this->fill_plt_entry(pov,
1631 got_address, plt_address,
1632 got_offset, plt_offset,
1635 // Set the entry in the GOT.
1636 elfcpp::Swap<64, false>::writeval(got_pov,
1637 plt_address + plt_offset + lazy_offset);
1640 if (this->has_tlsdesc_entry())
1642 // Set and adjust the reserved TLSDESC PLT entry.
1643 unsigned int tlsdesc_got_offset = this->get_tlsdesc_got_offset();
1644 this->fill_tlsdesc_entry(pov, got_address, plt_address, got_base,
1645 tlsdesc_got_offset, plt_offset);
1646 pov += this->get_plt_entry_size();
1649 gold_assert(static_cast<section_size_type>(pov - oview) == oview_size);
1650 gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size);
1652 of->write_output_view(offset, oview_size, oview);
1653 of->write_output_view(got_file_offset, got_size, got_view);
1656 // Create the PLT section.
1660 Target_x86_64<size>::make_plt_section(Symbol_table* symtab, Layout* layout)
1662 if (this->plt_ == NULL)
1664 // Create the GOT sections first.
1665 this->got_section(symtab, layout);
1667 this->plt_ = this->make_data_plt(layout, this->got_, this->got_plt_,
1668 this->got_irelative_);
1670 // Add unwind information if requested.
1671 if (parameters->options().ld_generated_unwind_info())
1672 this->plt_->add_eh_frame(layout);
1674 layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
1676 | elfcpp::SHF_EXECINSTR),
1677 this->plt_, ORDER_PLT, false);
1679 // Make the sh_info field of .rela.plt point to .plt.
1680 Output_section* rela_plt_os = this->plt_->rela_plt()->output_section();
1681 rela_plt_os->set_info_section(this->plt_->output_section());
1685 // Return the section for TLSDESC relocations.
1688 typename Target_x86_64<size>::Reloc_section*
1689 Target_x86_64<size>::rela_tlsdesc_section(Layout* layout) const
1691 return this->plt_section()->rela_tlsdesc(layout);
1694 // Create a PLT entry for a global symbol.
1698 Target_x86_64<size>::make_plt_entry(Symbol_table* symtab, Layout* layout,
1701 if (gsym->has_plt_offset())
1704 if (this->plt_ == NULL)
1705 this->make_plt_section(symtab, layout);
1707 this->plt_->add_entry(symtab, layout, gsym);
1710 // Make a PLT entry for a local STT_GNU_IFUNC symbol.
1714 Target_x86_64<size>::make_local_ifunc_plt_entry(
1715 Symbol_table* symtab, Layout* layout,
1716 Sized_relobj_file<size, false>* relobj,
1717 unsigned int local_sym_index)
1719 if (relobj->local_has_plt_offset(local_sym_index))
1721 if (this->plt_ == NULL)
1722 this->make_plt_section(symtab, layout);
1723 unsigned int plt_offset = this->plt_->add_local_ifunc_entry(symtab, layout,
1726 relobj->set_local_plt_offset(local_sym_index, plt_offset);
1729 // Return the number of entries in the PLT.
1733 Target_x86_64<size>::plt_entry_count() const
1735 if (this->plt_ == NULL)
1737 return this->plt_->entry_count();
1740 // Return the offset of the first non-reserved PLT entry.
1744 Target_x86_64<size>::first_plt_entry_offset() const
1746 return this->plt_->first_plt_entry_offset();
1749 // Return the size of each PLT entry.
1753 Target_x86_64<size>::plt_entry_size() const
1755 return this->plt_->get_plt_entry_size();
1758 // Create the GOT and PLT sections for an incremental update.
1761 Output_data_got_base*
1762 Target_x86_64<size>::init_got_plt_for_update(Symbol_table* symtab,
1764 unsigned int got_count,
1765 unsigned int plt_count)
1767 gold_assert(this->got_ == NULL);
1769 this->got_ = new Output_data_got<64, false>(got_count * 8);
1770 layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
1772 | elfcpp::SHF_WRITE),
1773 this->got_, ORDER_RELRO_LAST,
1776 // Add the three reserved entries.
1777 this->got_plt_ = new Output_data_space((plt_count + 3) * 8, 8, "** GOT PLT");
1778 layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
1780 | elfcpp::SHF_WRITE),
1781 this->got_plt_, ORDER_NON_RELRO_FIRST,
1784 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
1785 this->global_offset_table_ =
1786 symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
1787 Symbol_table::PREDEFINED,
1789 0, 0, elfcpp::STT_OBJECT,
1791 elfcpp::STV_HIDDEN, 0,
1794 // If there are any TLSDESC relocations, they get GOT entries in
1795 // .got.plt after the jump slot entries.
1796 // FIXME: Get the count for TLSDESC entries.
1797 this->got_tlsdesc_ = new Output_data_got<64, false>(0);
1798 layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
1799 elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE,
1801 ORDER_NON_RELRO_FIRST, false);
1803 // If there are any IRELATIVE relocations, they get GOT entries in
1804 // .got.plt after the jump slot and TLSDESC entries.
1805 this->got_irelative_ = new Output_data_space(0, 8, "** GOT IRELATIVE PLT");
1806 layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
1807 elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE,
1808 this->got_irelative_,
1809 ORDER_NON_RELRO_FIRST, false);
1811 // Create the PLT section.
1812 this->plt_ = this->make_data_plt(layout, this->got_,
1814 this->got_irelative_,
1817 // Add unwind information if requested.
1818 if (parameters->options().ld_generated_unwind_info())
1819 this->plt_->add_eh_frame(layout);
1821 layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
1822 elfcpp::SHF_ALLOC | elfcpp::SHF_EXECINSTR,
1823 this->plt_, ORDER_PLT, false);
1825 // Make the sh_info field of .rela.plt point to .plt.
1826 Output_section* rela_plt_os = this->plt_->rela_plt()->output_section();
1827 rela_plt_os->set_info_section(this->plt_->output_section());
1829 // Create the rela_dyn section.
1830 this->rela_dyn_section(layout);
1835 // Reserve a GOT entry for a local symbol, and regenerate any
1836 // necessary dynamic relocations.
1840 Target_x86_64<size>::reserve_local_got_entry(
1841 unsigned int got_index,
1842 Sized_relobj<size, false>* obj,
1844 unsigned int got_type)
1846 unsigned int got_offset = got_index * 8;
1847 Reloc_section* rela_dyn = this->rela_dyn_section(NULL);
1849 this->got_->reserve_local(got_index, obj, r_sym, got_type);
1852 case GOT_TYPE_STANDARD:
1853 if (parameters->options().output_is_position_independent())
1854 rela_dyn->add_local_relative(obj, r_sym, elfcpp::R_X86_64_RELATIVE,
1855 this->got_, got_offset, 0, false);
1857 case GOT_TYPE_TLS_OFFSET:
1858 rela_dyn->add_local(obj, r_sym, elfcpp::R_X86_64_TPOFF64,
1859 this->got_, got_offset, 0);
1861 case GOT_TYPE_TLS_PAIR:
1862 this->got_->reserve_slot(got_index + 1);
1863 rela_dyn->add_local(obj, r_sym, elfcpp::R_X86_64_DTPMOD64,
1864 this->got_, got_offset, 0);
1866 case GOT_TYPE_TLS_DESC:
1867 gold_fatal(_("TLS_DESC not yet supported for incremental linking"));
1868 // this->got_->reserve_slot(got_index + 1);
1869 // rela_dyn->add_target_specific(elfcpp::R_X86_64_TLSDESC, arg,
1870 // this->got_, got_offset, 0);
1877 // Reserve a GOT entry for a global symbol, and regenerate any
1878 // necessary dynamic relocations.
1882 Target_x86_64<size>::reserve_global_got_entry(unsigned int got_index,
1884 unsigned int got_type)
1886 unsigned int got_offset = got_index * 8;
1887 Reloc_section* rela_dyn = this->rela_dyn_section(NULL);
1889 this->got_->reserve_global(got_index, gsym, got_type);
1892 case GOT_TYPE_STANDARD:
1893 if (!gsym->final_value_is_known())
1895 if (gsym->is_from_dynobj()
1896 || gsym->is_undefined()
1897 || gsym->is_preemptible()
1898 || gsym->type() == elfcpp::STT_GNU_IFUNC)
1899 rela_dyn->add_global(gsym, elfcpp::R_X86_64_GLOB_DAT,
1900 this->got_, got_offset, 0);
1902 rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_RELATIVE,
1903 this->got_, got_offset, 0, false);
1906 case GOT_TYPE_TLS_OFFSET:
1907 rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_TPOFF64,
1908 this->got_, got_offset, 0, false);
1910 case GOT_TYPE_TLS_PAIR:
1911 this->got_->reserve_slot(got_index + 1);
1912 rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_DTPMOD64,
1913 this->got_, got_offset, 0, false);
1914 rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_DTPOFF64,
1915 this->got_, got_offset + 8, 0, false);
1917 case GOT_TYPE_TLS_DESC:
1918 this->got_->reserve_slot(got_index + 1);
1919 rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_TLSDESC,
1920 this->got_, got_offset, 0, false);
1927 // Register an existing PLT entry for a global symbol.
1931 Target_x86_64<size>::register_global_plt_entry(Symbol_table* symtab,
1933 unsigned int plt_index,
1936 gold_assert(this->plt_ != NULL);
1937 gold_assert(!gsym->has_plt_offset());
1939 this->plt_->reserve_slot(plt_index);
1941 gsym->set_plt_offset((plt_index + 1) * this->plt_entry_size());
1943 unsigned int got_offset = (plt_index + 3) * 8;
1944 this->plt_->add_relocation(symtab, layout, gsym, got_offset);
1947 // Force a COPY relocation for a given symbol.
1951 Target_x86_64<size>::emit_copy_reloc(
1952 Symbol_table* symtab, Symbol* sym, Output_section* os, off_t offset)
1954 this->copy_relocs_.emit_copy_reloc(symtab,
1955 symtab->get_sized_symbol<size>(sym),
1958 this->rela_dyn_section(NULL));
1961 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
1965 Target_x86_64<size>::define_tls_base_symbol(Symbol_table* symtab,
1968 if (this->tls_base_symbol_defined_)
1971 Output_segment* tls_segment = layout->tls_segment();
1972 if (tls_segment != NULL)
1974 bool is_exec = parameters->options().output_is_executable();
1975 symtab->define_in_output_segment("_TLS_MODULE_BASE_", NULL,
1976 Symbol_table::PREDEFINED,
1980 elfcpp::STV_HIDDEN, 0,
1982 ? Symbol::SEGMENT_END
1983 : Symbol::SEGMENT_START),
1986 this->tls_base_symbol_defined_ = true;
1989 // Create the reserved PLT and GOT entries for the TLS descriptor resolver.
1993 Target_x86_64<size>::reserve_tlsdesc_entries(Symbol_table* symtab,
1996 if (this->plt_ == NULL)
1997 this->make_plt_section(symtab, layout);
1999 if (!this->plt_->has_tlsdesc_entry())
2001 // Allocate the TLSDESC_GOT entry.
2002 Output_data_got<64, false>* got = this->got_section(symtab, layout);
2003 unsigned int got_offset = got->add_constant(0);
2005 // Allocate the TLSDESC_PLT entry.
2006 this->plt_->reserve_tlsdesc_entry(got_offset);
2010 // Create a GOT entry for the TLS module index.
2014 Target_x86_64<size>::got_mod_index_entry(Symbol_table* symtab, Layout* layout,
2015 Sized_relobj_file<size, false>* object)
2017 if (this->got_mod_index_offset_ == -1U)
2019 gold_assert(symtab != NULL && layout != NULL && object != NULL);
2020 Reloc_section* rela_dyn = this->rela_dyn_section(layout);
2021 Output_data_got<64, false>* got = this->got_section(symtab, layout);
2022 unsigned int got_offset = got->add_constant(0);
2023 rela_dyn->add_local(object, 0, elfcpp::R_X86_64_DTPMOD64, got,
2025 got->add_constant(0);
2026 this->got_mod_index_offset_ = got_offset;
2028 return this->got_mod_index_offset_;
2031 // Optimize the TLS relocation type based on what we know about the
2032 // symbol. IS_FINAL is true if the final address of this symbol is
2033 // known at link time.
2036 tls::Tls_optimization
2037 Target_x86_64<size>::optimize_tls_reloc(bool is_final, int r_type)
2039 // If we are generating a shared library, then we can't do anything
2041 if (parameters->options().shared())
2042 return tls::TLSOPT_NONE;
2046 case elfcpp::R_X86_64_TLSGD:
2047 case elfcpp::R_X86_64_GOTPC32_TLSDESC:
2048 case elfcpp::R_X86_64_TLSDESC_CALL:
2049 // These are General-Dynamic which permits fully general TLS
2050 // access. Since we know that we are generating an executable,
2051 // we can convert this to Initial-Exec. If we also know that
2052 // this is a local symbol, we can further switch to Local-Exec.
2054 return tls::TLSOPT_TO_LE;
2055 return tls::TLSOPT_TO_IE;
2057 case elfcpp::R_X86_64_TLSLD:
2058 // This is Local-Dynamic, which refers to a local symbol in the
2059 // dynamic TLS block. Since we know that we generating an
2060 // executable, we can switch to Local-Exec.
2061 return tls::TLSOPT_TO_LE;
2063 case elfcpp::R_X86_64_DTPOFF32:
2064 case elfcpp::R_X86_64_DTPOFF64:
2065 // Another Local-Dynamic reloc.
2066 return tls::TLSOPT_TO_LE;
2068 case elfcpp::R_X86_64_GOTTPOFF:
2069 // These are Initial-Exec relocs which get the thread offset
2070 // from the GOT. If we know that we are linking against the
2071 // local symbol, we can switch to Local-Exec, which links the
2072 // thread offset into the instruction.
2074 return tls::TLSOPT_TO_LE;
2075 return tls::TLSOPT_NONE;
2077 case elfcpp::R_X86_64_TPOFF32:
2078 // When we already have Local-Exec, there is nothing further we
2080 return tls::TLSOPT_NONE;
2087 // Get the Reference_flags for a particular relocation.
2091 Target_x86_64<size>::Scan::get_reference_flags(unsigned int r_type)
2095 case elfcpp::R_X86_64_NONE:
2096 case elfcpp::R_X86_64_GNU_VTINHERIT:
2097 case elfcpp::R_X86_64_GNU_VTENTRY:
2098 case elfcpp::R_X86_64_GOTPC32:
2099 case elfcpp::R_X86_64_GOTPC64:
2100 // No symbol reference.
2103 case elfcpp::R_X86_64_64:
2104 case elfcpp::R_X86_64_32:
2105 case elfcpp::R_X86_64_32S:
2106 case elfcpp::R_X86_64_16:
2107 case elfcpp::R_X86_64_8:
2108 return Symbol::ABSOLUTE_REF;
2110 case elfcpp::R_X86_64_PC64:
2111 case elfcpp::R_X86_64_PC32:
2112 case elfcpp::R_X86_64_PC16:
2113 case elfcpp::R_X86_64_PC8:
2114 case elfcpp::R_X86_64_GOTOFF64:
2115 return Symbol::RELATIVE_REF;
2117 case elfcpp::R_X86_64_PLT32:
2118 case elfcpp::R_X86_64_PLTOFF64:
2119 return Symbol::FUNCTION_CALL | Symbol::RELATIVE_REF;
2121 case elfcpp::R_X86_64_GOT64:
2122 case elfcpp::R_X86_64_GOT32:
2123 case elfcpp::R_X86_64_GOTPCREL64:
2124 case elfcpp::R_X86_64_GOTPCREL:
2125 case elfcpp::R_X86_64_GOTPLT64:
2127 return Symbol::ABSOLUTE_REF;
2129 case elfcpp::R_X86_64_TLSGD: // Global-dynamic
2130 case elfcpp::R_X86_64_GOTPC32_TLSDESC: // Global-dynamic (from ~oliva url)
2131 case elfcpp::R_X86_64_TLSDESC_CALL:
2132 case elfcpp::R_X86_64_TLSLD: // Local-dynamic
2133 case elfcpp::R_X86_64_DTPOFF32:
2134 case elfcpp::R_X86_64_DTPOFF64:
2135 case elfcpp::R_X86_64_GOTTPOFF: // Initial-exec
2136 case elfcpp::R_X86_64_TPOFF32: // Local-exec
2137 return Symbol::TLS_REF;
2139 case elfcpp::R_X86_64_COPY:
2140 case elfcpp::R_X86_64_GLOB_DAT:
2141 case elfcpp::R_X86_64_JUMP_SLOT:
2142 case elfcpp::R_X86_64_RELATIVE:
2143 case elfcpp::R_X86_64_IRELATIVE:
2144 case elfcpp::R_X86_64_TPOFF64:
2145 case elfcpp::R_X86_64_DTPMOD64:
2146 case elfcpp::R_X86_64_TLSDESC:
2147 case elfcpp::R_X86_64_SIZE32:
2148 case elfcpp::R_X86_64_SIZE64:
2150 // Not expected. We will give an error later.
2155 // Report an unsupported relocation against a local symbol.
2159 Target_x86_64<size>::Scan::unsupported_reloc_local(
2160 Sized_relobj_file<size, false>* object,
2161 unsigned int r_type)
2163 gold_error(_("%s: unsupported reloc %u against local symbol"),
2164 object->name().c_str(), r_type);
2167 // We are about to emit a dynamic relocation of type R_TYPE. If the
2168 // dynamic linker does not support it, issue an error. The GNU linker
2169 // only issues a non-PIC error for an allocated read-only section.
2170 // Here we know the section is allocated, but we don't know that it is
2171 // read-only. But we check for all the relocation types which the
2172 // glibc dynamic linker supports, so it seems appropriate to issue an
2173 // error even if the section is not read-only. If GSYM is not NULL,
2174 // it is the symbol the relocation is against; if it is NULL, the
2175 // relocation is against a local symbol.
2179 Target_x86_64<size>::Scan::check_non_pic(Relobj* object, unsigned int r_type,
2184 // These are the relocation types supported by glibc for x86_64
2185 // which should always work.
2186 case elfcpp::R_X86_64_RELATIVE:
2187 case elfcpp::R_X86_64_IRELATIVE:
2188 case elfcpp::R_X86_64_GLOB_DAT:
2189 case elfcpp::R_X86_64_JUMP_SLOT:
2190 case elfcpp::R_X86_64_DTPMOD64:
2191 case elfcpp::R_X86_64_DTPOFF64:
2192 case elfcpp::R_X86_64_TPOFF64:
2193 case elfcpp::R_X86_64_64:
2194 case elfcpp::R_X86_64_COPY:
2197 // glibc supports these reloc types, but they can overflow.
2198 case elfcpp::R_X86_64_PC32:
2199 // A PC relative reference is OK against a local symbol or if
2200 // the symbol is defined locally.
2202 || (!gsym->is_from_dynobj()
2203 && !gsym->is_undefined()
2204 && !gsym->is_preemptible()))
2207 case elfcpp::R_X86_64_32:
2208 // R_X86_64_32 is OK for x32.
2209 if (size == 32 && r_type == elfcpp::R_X86_64_32)
2211 if (this->issued_non_pic_error_)
2213 gold_assert(parameters->options().output_is_position_independent());
2215 object->error(_("requires dynamic R_X86_64_32 reloc which may "
2216 "overflow at runtime; recompile with -fPIC"));
2218 object->error(_("requires dynamic %s reloc against '%s' which may "
2219 "overflow at runtime; recompile with -fPIC"),
2220 (r_type == elfcpp::R_X86_64_32
2224 this->issued_non_pic_error_ = true;
2228 // This prevents us from issuing more than one error per reloc
2229 // section. But we can still wind up issuing more than one
2230 // error per object file.
2231 if (this->issued_non_pic_error_)
2233 gold_assert(parameters->options().output_is_position_independent());
2234 object->error(_("requires unsupported dynamic reloc %u; "
2235 "recompile with -fPIC"),
2237 this->issued_non_pic_error_ = true;
2240 case elfcpp::R_X86_64_NONE:
2245 // Return whether we need to make a PLT entry for a relocation of the
2246 // given type against a STT_GNU_IFUNC symbol.
2250 Target_x86_64<size>::Scan::reloc_needs_plt_for_ifunc(
2251 Sized_relobj_file<size, false>* object,
2252 unsigned int r_type)
2254 int flags = Scan::get_reference_flags(r_type);
2255 if (flags & Symbol::TLS_REF)
2256 gold_error(_("%s: unsupported TLS reloc %u for IFUNC symbol"),
2257 object->name().c_str(), r_type);
2261 // Scan a relocation for a local symbol.
2265 Target_x86_64<size>::Scan::local(Symbol_table* symtab,
2267 Target_x86_64<size>* target,
2268 Sized_relobj_file<size, false>* object,
2269 unsigned int data_shndx,
2270 Output_section* output_section,
2271 const elfcpp::Rela<size, false>& reloc,
2272 unsigned int r_type,
2273 const elfcpp::Sym<size, false>& lsym)
2275 // A local STT_GNU_IFUNC symbol may require a PLT entry.
2276 bool is_ifunc = lsym.get_st_type() == elfcpp::STT_GNU_IFUNC;
2277 if (is_ifunc && this->reloc_needs_plt_for_ifunc(object, r_type))
2279 unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2280 target->make_local_ifunc_plt_entry(symtab, layout, object, r_sym);
2285 case elfcpp::R_X86_64_NONE:
2286 case elfcpp::R_X86_64_GNU_VTINHERIT:
2287 case elfcpp::R_X86_64_GNU_VTENTRY:
2290 case elfcpp::R_X86_64_64:
2291 // If building a shared library (or a position-independent
2292 // executable), we need to create a dynamic relocation for this
2293 // location. The relocation applied at link time will apply the
2294 // link-time value, so we flag the location with an
2295 // R_X86_64_RELATIVE relocation so the dynamic loader can
2296 // relocate it easily.
2297 if (parameters->options().output_is_position_independent())
2299 unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2300 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2301 rela_dyn->add_local_relative(object, r_sym,
2302 elfcpp::R_X86_64_RELATIVE,
2303 output_section, data_shndx,
2304 reloc.get_r_offset(),
2305 reloc.get_r_addend(), is_ifunc);
2309 case elfcpp::R_X86_64_32:
2310 case elfcpp::R_X86_64_32S:
2311 case elfcpp::R_X86_64_16:
2312 case elfcpp::R_X86_64_8:
2313 // If building a shared library (or a position-independent
2314 // executable), we need to create a dynamic relocation for this
2315 // location. We can't use an R_X86_64_RELATIVE relocation
2316 // because that is always a 64-bit relocation.
2317 if (parameters->options().output_is_position_independent())
2319 // Use R_X86_64_RELATIVE relocation for R_X86_64_32 under x32.
2320 if (size == 32 && r_type == elfcpp::R_X86_64_32)
2322 unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2323 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2324 rela_dyn->add_local_relative(object, r_sym,
2325 elfcpp::R_X86_64_RELATIVE,
2326 output_section, data_shndx,
2327 reloc.get_r_offset(),
2328 reloc.get_r_addend(), is_ifunc);
2332 this->check_non_pic(object, r_type, NULL);
2334 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2335 unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2336 if (lsym.get_st_type() != elfcpp::STT_SECTION)
2337 rela_dyn->add_local(object, r_sym, r_type, output_section,
2338 data_shndx, reloc.get_r_offset(),
2339 reloc.get_r_addend());
2342 gold_assert(lsym.get_st_value() == 0);
2343 unsigned int shndx = lsym.get_st_shndx();
2345 shndx = object->adjust_sym_shndx(r_sym, shndx,
2348 object->error(_("section symbol %u has bad shndx %u"),
2351 rela_dyn->add_local_section(object, shndx,
2352 r_type, output_section,
2353 data_shndx, reloc.get_r_offset(),
2354 reloc.get_r_addend());
2359 case elfcpp::R_X86_64_PC64:
2360 case elfcpp::R_X86_64_PC32:
2361 case elfcpp::R_X86_64_PC16:
2362 case elfcpp::R_X86_64_PC8:
2365 case elfcpp::R_X86_64_PLT32:
2366 // Since we know this is a local symbol, we can handle this as a
2370 case elfcpp::R_X86_64_GOTPC32:
2371 case elfcpp::R_X86_64_GOTOFF64:
2372 case elfcpp::R_X86_64_GOTPC64:
2373 case elfcpp::R_X86_64_PLTOFF64:
2374 // We need a GOT section.
2375 target->got_section(symtab, layout);
2376 // For PLTOFF64, we'd normally want a PLT section, but since we
2377 // know this is a local symbol, no PLT is needed.
2380 case elfcpp::R_X86_64_GOT64:
2381 case elfcpp::R_X86_64_GOT32:
2382 case elfcpp::R_X86_64_GOTPCREL64:
2383 case elfcpp::R_X86_64_GOTPCREL:
2384 case elfcpp::R_X86_64_GOTPLT64:
2386 // The symbol requires a GOT entry.
2387 Output_data_got<64, false>* got = target->got_section(symtab, layout);
2388 unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2390 // For a STT_GNU_IFUNC symbol we want the PLT offset. That
2391 // lets function pointers compare correctly with shared
2392 // libraries. Otherwise we would need an IRELATIVE reloc.
2395 is_new = got->add_local_plt(object, r_sym, GOT_TYPE_STANDARD);
2397 is_new = got->add_local(object, r_sym, GOT_TYPE_STANDARD);
2400 // If we are generating a shared object, we need to add a
2401 // dynamic relocation for this symbol's GOT entry.
2402 if (parameters->options().output_is_position_independent())
2404 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2405 // R_X86_64_RELATIVE assumes a 64-bit relocation.
2406 if (r_type != elfcpp::R_X86_64_GOT32)
2408 unsigned int got_offset =
2409 object->local_got_offset(r_sym, GOT_TYPE_STANDARD);
2410 rela_dyn->add_local_relative(object, r_sym,
2411 elfcpp::R_X86_64_RELATIVE,
2412 got, got_offset, 0, is_ifunc);
2416 this->check_non_pic(object, r_type, NULL);
2418 gold_assert(lsym.get_st_type() != elfcpp::STT_SECTION);
2419 rela_dyn->add_local(
2420 object, r_sym, r_type, got,
2421 object->local_got_offset(r_sym, GOT_TYPE_STANDARD), 0);
2425 // For GOTPLT64, we'd normally want a PLT section, but since
2426 // we know this is a local symbol, no PLT is needed.
2430 case elfcpp::R_X86_64_COPY:
2431 case elfcpp::R_X86_64_GLOB_DAT:
2432 case elfcpp::R_X86_64_JUMP_SLOT:
2433 case elfcpp::R_X86_64_RELATIVE:
2434 case elfcpp::R_X86_64_IRELATIVE:
2435 // These are outstanding tls relocs, which are unexpected when linking
2436 case elfcpp::R_X86_64_TPOFF64:
2437 case elfcpp::R_X86_64_DTPMOD64:
2438 case elfcpp::R_X86_64_TLSDESC:
2439 gold_error(_("%s: unexpected reloc %u in object file"),
2440 object->name().c_str(), r_type);
2443 // These are initial tls relocs, which are expected when linking
2444 case elfcpp::R_X86_64_TLSGD: // Global-dynamic
2445 case elfcpp::R_X86_64_GOTPC32_TLSDESC: // Global-dynamic (from ~oliva url)
2446 case elfcpp::R_X86_64_TLSDESC_CALL:
2447 case elfcpp::R_X86_64_TLSLD: // Local-dynamic
2448 case elfcpp::R_X86_64_DTPOFF32:
2449 case elfcpp::R_X86_64_DTPOFF64:
2450 case elfcpp::R_X86_64_GOTTPOFF: // Initial-exec
2451 case elfcpp::R_X86_64_TPOFF32: // Local-exec
2453 bool output_is_shared = parameters->options().shared();
2454 const tls::Tls_optimization optimized_type
2455 = Target_x86_64<size>::optimize_tls_reloc(!output_is_shared,
2459 case elfcpp::R_X86_64_TLSGD: // General-dynamic
2460 if (optimized_type == tls::TLSOPT_NONE)
2462 // Create a pair of GOT entries for the module index and
2463 // dtv-relative offset.
2464 Output_data_got<64, false>* got
2465 = target->got_section(symtab, layout);
2466 unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2467 unsigned int shndx = lsym.get_st_shndx();
2469 shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
2471 object->error(_("local symbol %u has bad shndx %u"),
2474 got->add_local_pair_with_rel(object, r_sym,
2477 target->rela_dyn_section(layout),
2478 elfcpp::R_X86_64_DTPMOD64, 0);
2480 else if (optimized_type != tls::TLSOPT_TO_LE)
2481 unsupported_reloc_local(object, r_type);
2484 case elfcpp::R_X86_64_GOTPC32_TLSDESC:
2485 target->define_tls_base_symbol(symtab, layout);
2486 if (optimized_type == tls::TLSOPT_NONE)
2488 // Create reserved PLT and GOT entries for the resolver.
2489 target->reserve_tlsdesc_entries(symtab, layout);
2491 // Generate a double GOT entry with an
2492 // R_X86_64_TLSDESC reloc. The R_X86_64_TLSDESC reloc
2493 // is resolved lazily, so the GOT entry needs to be in
2494 // an area in .got.plt, not .got. Call got_section to
2495 // make sure the section has been created.
2496 target->got_section(symtab, layout);
2497 Output_data_got<64, false>* got = target->got_tlsdesc_section();
2498 unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2499 if (!object->local_has_got_offset(r_sym, GOT_TYPE_TLS_DESC))
2501 unsigned int got_offset = got->add_constant(0);
2502 got->add_constant(0);
2503 object->set_local_got_offset(r_sym, GOT_TYPE_TLS_DESC,
2505 Reloc_section* rt = target->rela_tlsdesc_section(layout);
2506 // We store the arguments we need in a vector, and
2507 // use the index into the vector as the parameter
2508 // to pass to the target specific routines.
2509 uintptr_t intarg = target->add_tlsdesc_info(object, r_sym);
2510 void* arg = reinterpret_cast<void*>(intarg);
2511 rt->add_target_specific(elfcpp::R_X86_64_TLSDESC, arg,
2512 got, got_offset, 0);
2515 else if (optimized_type != tls::TLSOPT_TO_LE)
2516 unsupported_reloc_local(object, r_type);
2519 case elfcpp::R_X86_64_TLSDESC_CALL:
2522 case elfcpp::R_X86_64_TLSLD: // Local-dynamic
2523 if (optimized_type == tls::TLSOPT_NONE)
2525 // Create a GOT entry for the module index.
2526 target->got_mod_index_entry(symtab, layout, object);
2528 else if (optimized_type != tls::TLSOPT_TO_LE)
2529 unsupported_reloc_local(object, r_type);
2532 case elfcpp::R_X86_64_DTPOFF32:
2533 case elfcpp::R_X86_64_DTPOFF64:
2536 case elfcpp::R_X86_64_GOTTPOFF: // Initial-exec
2537 layout->set_has_static_tls();
2538 if (optimized_type == tls::TLSOPT_NONE)
2540 // Create a GOT entry for the tp-relative offset.
2541 Output_data_got<64, false>* got
2542 = target->got_section(symtab, layout);
2543 unsigned int r_sym = elfcpp::elf_r_sym<size>(reloc.get_r_info());
2544 got->add_local_with_rel(object, r_sym, GOT_TYPE_TLS_OFFSET,
2545 target->rela_dyn_section(layout),
2546 elfcpp::R_X86_64_TPOFF64);
2548 else if (optimized_type != tls::TLSOPT_TO_LE)
2549 unsupported_reloc_local(object, r_type);
2552 case elfcpp::R_X86_64_TPOFF32: // Local-exec
2553 layout->set_has_static_tls();
2554 if (output_is_shared)
2555 unsupported_reloc_local(object, r_type);
2564 case elfcpp::R_X86_64_SIZE32:
2565 case elfcpp::R_X86_64_SIZE64:
2567 gold_error(_("%s: unsupported reloc %u against local symbol"),
2568 object->name().c_str(), r_type);
2574 // Report an unsupported relocation against a global symbol.
2578 Target_x86_64<size>::Scan::unsupported_reloc_global(
2579 Sized_relobj_file<size, false>* object,
2580 unsigned int r_type,
2583 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
2584 object->name().c_str(), r_type, gsym->demangled_name().c_str());
2587 // Returns true if this relocation type could be that of a function pointer.
2590 Target_x86_64<size>::Scan::possible_function_pointer_reloc(unsigned int r_type)
2594 case elfcpp::R_X86_64_64:
2595 case elfcpp::R_X86_64_32:
2596 case elfcpp::R_X86_64_32S:
2597 case elfcpp::R_X86_64_16:
2598 case elfcpp::R_X86_64_8:
2599 case elfcpp::R_X86_64_GOT64:
2600 case elfcpp::R_X86_64_GOT32:
2601 case elfcpp::R_X86_64_GOTPCREL64:
2602 case elfcpp::R_X86_64_GOTPCREL:
2603 case elfcpp::R_X86_64_GOTPLT64:
2611 // For safe ICF, scan a relocation for a local symbol to check if it
2612 // corresponds to a function pointer being taken. In that case mark
2613 // the function whose pointer was taken as not foldable.
2617 Target_x86_64<size>::Scan::local_reloc_may_be_function_pointer(
2620 Target_x86_64<size>* ,
2621 Sized_relobj_file<size, false>* ,
2624 const elfcpp::Rela<size, false>& ,
2625 unsigned int r_type,
2626 const elfcpp::Sym<size, false>&)
2628 // When building a shared library, do not fold any local symbols as it is
2629 // not possible to distinguish pointer taken versus a call by looking at
2630 // the relocation types.
2631 return (parameters->options().shared()
2632 || possible_function_pointer_reloc(r_type));
2635 // For safe ICF, scan a relocation for a global symbol to check if it
2636 // corresponds to a function pointer being taken. In that case mark
2637 // the function whose pointer was taken as not foldable.
2641 Target_x86_64<size>::Scan::global_reloc_may_be_function_pointer(
2644 Target_x86_64<size>* ,
2645 Sized_relobj_file<size, false>* ,
2648 const elfcpp::Rela<size, false>& ,
2649 unsigned int r_type,
2652 // When building a shared library, do not fold symbols whose visibility
2653 // is hidden, internal or protected.
2654 return ((parameters->options().shared()
2655 && (gsym->visibility() == elfcpp::STV_INTERNAL
2656 || gsym->visibility() == elfcpp::STV_PROTECTED
2657 || gsym->visibility() == elfcpp::STV_HIDDEN))
2658 || possible_function_pointer_reloc(r_type));
2661 // Scan a relocation for a global symbol.
2665 Target_x86_64<size>::Scan::global(Symbol_table* symtab,
2667 Target_x86_64<size>* target,
2668 Sized_relobj_file<size, false>* object,
2669 unsigned int data_shndx,
2670 Output_section* output_section,
2671 const elfcpp::Rela<size, false>& reloc,
2672 unsigned int r_type,
2675 // A STT_GNU_IFUNC symbol may require a PLT entry.
2676 if (gsym->type() == elfcpp::STT_GNU_IFUNC
2677 && this->reloc_needs_plt_for_ifunc(object, r_type))
2678 target->make_plt_entry(symtab, layout, gsym);
2682 case elfcpp::R_X86_64_NONE:
2683 case elfcpp::R_X86_64_GNU_VTINHERIT:
2684 case elfcpp::R_X86_64_GNU_VTENTRY:
2687 case elfcpp::R_X86_64_64:
2688 case elfcpp::R_X86_64_32:
2689 case elfcpp::R_X86_64_32S:
2690 case elfcpp::R_X86_64_16:
2691 case elfcpp::R_X86_64_8:
2693 // Make a PLT entry if necessary.
2694 if (gsym->needs_plt_entry())
2696 target->make_plt_entry(symtab, layout, gsym);
2697 // Since this is not a PC-relative relocation, we may be
2698 // taking the address of a function. In that case we need to
2699 // set the entry in the dynamic symbol table to the address of
2701 if (gsym->is_from_dynobj() && !parameters->options().shared())
2702 gsym->set_needs_dynsym_value();
2704 // Make a dynamic relocation if necessary.
2705 if (gsym->needs_dynamic_reloc(Scan::get_reference_flags(r_type)))
2707 if (gsym->may_need_copy_reloc())
2709 target->copy_reloc(symtab, layout, object,
2710 data_shndx, output_section, gsym, reloc);
2712 else if (((size == 64 && r_type == elfcpp::R_X86_64_64)
2713 || (size == 32 && r_type == elfcpp::R_X86_64_32))
2714 && gsym->type() == elfcpp::STT_GNU_IFUNC
2715 && gsym->can_use_relative_reloc(false)
2716 && !gsym->is_from_dynobj()
2717 && !gsym->is_undefined()
2718 && !gsym->is_preemptible())
2720 // Use an IRELATIVE reloc for a locally defined
2721 // STT_GNU_IFUNC symbol. This makes a function
2722 // address in a PIE executable match the address in a
2723 // shared library that it links against.
2724 Reloc_section* rela_dyn =
2725 target->rela_irelative_section(layout);
2726 unsigned int r_type = elfcpp::R_X86_64_IRELATIVE;
2727 rela_dyn->add_symbolless_global_addend(gsym, r_type,
2728 output_section, object,
2730 reloc.get_r_offset(),
2731 reloc.get_r_addend());
2733 else if (r_type == elfcpp::R_X86_64_64
2734 && gsym->can_use_relative_reloc(false))
2736 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2737 rela_dyn->add_global_relative(gsym, elfcpp::R_X86_64_RELATIVE,
2738 output_section, object,
2740 reloc.get_r_offset(),
2741 reloc.get_r_addend(), false);
2745 this->check_non_pic(object, r_type, gsym);
2746 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2747 rela_dyn->add_global(gsym, r_type, output_section, object,
2748 data_shndx, reloc.get_r_offset(),
2749 reloc.get_r_addend());
2755 case elfcpp::R_X86_64_PC64:
2756 case elfcpp::R_X86_64_PC32:
2757 case elfcpp::R_X86_64_PC16:
2758 case elfcpp::R_X86_64_PC8:
2760 // Make a PLT entry if necessary.
2761 if (gsym->needs_plt_entry())
2762 target->make_plt_entry(symtab, layout, gsym);
2763 // Make a dynamic relocation if necessary.
2764 if (gsym->needs_dynamic_reloc(Scan::get_reference_flags(r_type)))
2766 if (gsym->may_need_copy_reloc())
2768 target->copy_reloc(symtab, layout, object,
2769 data_shndx, output_section, gsym, reloc);
2773 this->check_non_pic(object, r_type, gsym);
2774 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2775 rela_dyn->add_global(gsym, r_type, output_section, object,
2776 data_shndx, reloc.get_r_offset(),
2777 reloc.get_r_addend());
2783 case elfcpp::R_X86_64_GOT64:
2784 case elfcpp::R_X86_64_GOT32:
2785 case elfcpp::R_X86_64_GOTPCREL64:
2786 case elfcpp::R_X86_64_GOTPCREL:
2787 case elfcpp::R_X86_64_GOTPLT64:
2789 // The symbol requires a GOT entry.
2790 Output_data_got<64, false>* got = target->got_section(symtab, layout);
2791 if (gsym->final_value_is_known())
2793 // For a STT_GNU_IFUNC symbol we want the PLT address.
2794 if (gsym->type() == elfcpp::STT_GNU_IFUNC)
2795 got->add_global_plt(gsym, GOT_TYPE_STANDARD);
2797 got->add_global(gsym, GOT_TYPE_STANDARD);
2801 // If this symbol is not fully resolved, we need to add a
2802 // dynamic relocation for it.
2803 Reloc_section* rela_dyn = target->rela_dyn_section(layout);
2805 // Use a GLOB_DAT rather than a RELATIVE reloc if:
2807 // 1) The symbol may be defined in some other module.
2809 // 2) We are building a shared library and this is a
2810 // protected symbol; using GLOB_DAT means that the dynamic
2811 // linker can use the address of the PLT in the main
2812 // executable when appropriate so that function address
2813 // comparisons work.
2815 // 3) This is a STT_GNU_IFUNC symbol in position dependent
2816 // code, again so that function address comparisons work.
2817 if (gsym->is_from_dynobj()
2818 || gsym->is_undefined()
2819 || gsym->is_preemptible()
2820 || (gsym->visibility() == elfcpp::STV_PROTECTED
2821 && parameters->options().shared())
2822 || (gsym->type() == elfcpp::STT_GNU_IFUNC
2823 && parameters->options().output_is_position_independent()))
2824 got->add_global_with_rel(gsym, GOT_TYPE_STANDARD, rela_dyn,
2825 elfcpp::R_X86_64_GLOB_DAT);
2828 // For a STT_GNU_IFUNC symbol we want to write the PLT
2829 // offset into the GOT, so that function pointer
2830 // comparisons work correctly.
2832 if (gsym->type() != elfcpp::STT_GNU_IFUNC)
2833 is_new = got->add_global(gsym, GOT_TYPE_STANDARD);
2836 is_new = got->add_global_plt(gsym, GOT_TYPE_STANDARD);
2837 // Tell the dynamic linker to use the PLT address
2838 // when resolving relocations.
2839 if (gsym->is_from_dynobj()
2840 && !parameters->options().shared())
2841 gsym->set_needs_dynsym_value();
2845 unsigned int got_off = gsym->got_offset(GOT_TYPE_STANDARD);
2846 rela_dyn->add_global_relative(gsym,
2847 elfcpp::R_X86_64_RELATIVE,
2848 got, got_off, 0, false);
2852 // For GOTPLT64, we also need a PLT entry (but only if the
2853 // symbol is not fully resolved).
2854 if (r_type == elfcpp::R_X86_64_GOTPLT64
2855 && !gsym->final_value_is_known())
2856 target->make_plt_entry(symtab, layout, gsym);
2860 case elfcpp::R_X86_64_PLT32:
2861 // If the symbol is fully resolved, this is just a PC32 reloc.
2862 // Otherwise we need a PLT entry.
2863 if (gsym->final_value_is_known())
2865 // If building a shared library, we can also skip the PLT entry
2866 // if the symbol is defined in the output file and is protected
2868 if (gsym->is_defined()
2869 && !gsym->is_from_dynobj()
2870 && !gsym->is_preemptible())
2872 target->make_plt_entry(symtab, layout, gsym);
2875 case elfcpp::R_X86_64_GOTPC32:
2876 case elfcpp::R_X86_64_GOTOFF64:
2877 case elfcpp::R_X86_64_GOTPC64:
2878 case elfcpp::R_X86_64_PLTOFF64:
2879 // We need a GOT section.
2880 target->got_section(symtab, layout);
2881 // For PLTOFF64, we also need a PLT entry (but only if the
2882 // symbol is not fully resolved).
2883 if (r_type == elfcpp::R_X86_64_PLTOFF64
2884 && !gsym->final_value_is_known())
2885 target->make_plt_entry(symtab, layout, gsym);
2888 case elfcpp::R_X86_64_COPY:
2889 case elfcpp::R_X86_64_GLOB_DAT:
2890 case elfcpp::R_X86_64_JUMP_SLOT:
2891 case elfcpp::R_X86_64_RELATIVE:
2892 case elfcpp::R_X86_64_IRELATIVE:
2893 // These are outstanding tls relocs, which are unexpected when linking
2894 case elfcpp::R_X86_64_TPOFF64:
2895 case elfcpp::R_X86_64_DTPMOD64:
2896 case elfcpp::R_X86_64_TLSDESC:
2897 gold_error(_("%s: unexpected reloc %u in object file"),
2898 object->name().c_str(), r_type);
2901 // These are initial tls relocs, which are expected for global()
2902 case elfcpp::R_X86_64_TLSGD: // Global-dynamic
2903 case elfcpp::R_X86_64_GOTPC32_TLSDESC: // Global-dynamic (from ~oliva url)
2904 case elfcpp::R_X86_64_TLSDESC_CALL:
2905 case elfcpp::R_X86_64_TLSLD: // Local-dynamic
2906 case elfcpp::R_X86_64_DTPOFF32:
2907 case elfcpp::R_X86_64_DTPOFF64:
2908 case elfcpp::R_X86_64_GOTTPOFF: // Initial-exec
2909 case elfcpp::R_X86_64_TPOFF32: // Local-exec
2911 const bool is_final = gsym->final_value_is_known();
2912 const tls::Tls_optimization optimized_type
2913 = Target_x86_64<size>::optimize_tls_reloc(is_final, r_type);
2916 case elfcpp::R_X86_64_TLSGD: // General-dynamic
2917 if (optimized_type == tls::TLSOPT_NONE)
2919 // Create a pair of GOT entries for the module index and
2920 // dtv-relative offset.
2921 Output_data_got<64, false>* got
2922 = target->got_section(symtab, layout);
2923 got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_PAIR,
2924 target->rela_dyn_section(layout),
2925 elfcpp::R_X86_64_DTPMOD64,
2926 elfcpp::R_X86_64_DTPOFF64);
2928 else if (optimized_type == tls::TLSOPT_TO_IE)
2930 // Create a GOT entry for the tp-relative offset.
2931 Output_data_got<64, false>* got
2932 = target->got_section(symtab, layout);
2933 got->add_global_with_rel(gsym, GOT_TYPE_TLS_OFFSET,
2934 target->rela_dyn_section(layout),
2935 elfcpp::R_X86_64_TPOFF64);
2937 else if (optimized_type != tls::TLSOPT_TO_LE)
2938 unsupported_reloc_global(object, r_type, gsym);
2941 case elfcpp::R_X86_64_GOTPC32_TLSDESC:
2942 target->define_tls_base_symbol(symtab, layout);
2943 if (optimized_type == tls::TLSOPT_NONE)
2945 // Create reserved PLT and GOT entries for the resolver.
2946 target->reserve_tlsdesc_entries(symtab, layout);
2948 // Create a double GOT entry with an R_X86_64_TLSDESC
2949 // reloc. The R_X86_64_TLSDESC reloc is resolved
2950 // lazily, so the GOT entry needs to be in an area in
2951 // .got.plt, not .got. Call got_section to make sure
2952 // the section has been created.
2953 target->got_section(symtab, layout);
2954 Output_data_got<64, false>* got = target->got_tlsdesc_section();
2955 Reloc_section* rt = target->rela_tlsdesc_section(layout);
2956 got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_DESC, rt,
2957 elfcpp::R_X86_64_TLSDESC, 0);
2959 else if (optimized_type == tls::TLSOPT_TO_IE)
2961 // Create a GOT entry for the tp-relative offset.
2962 Output_data_got<64, false>* got
2963 = target->got_section(symtab, layout);
2964 got->add_global_with_rel(gsym, GOT_TYPE_TLS_OFFSET,
2965 target->rela_dyn_section(layout),
2966 elfcpp::R_X86_64_TPOFF64);
2968 else if (optimized_type != tls::TLSOPT_TO_LE)
2969 unsupported_reloc_global(object, r_type, gsym);
2972 case elfcpp::R_X86_64_TLSDESC_CALL:
2975 case elfcpp::R_X86_64_TLSLD: // Local-dynamic
2976 if (optimized_type == tls::TLSOPT_NONE)
2978 // Create a GOT entry for the module index.
2979 target->got_mod_index_entry(symtab, layout, object);
2981 else if (optimized_type != tls::TLSOPT_TO_LE)
2982 unsupported_reloc_global(object, r_type, gsym);
2985 case elfcpp::R_X86_64_DTPOFF32:
2986 case elfcpp::R_X86_64_DTPOFF64:
2989 case elfcpp::R_X86_64_GOTTPOFF: // Initial-exec
2990 layout->set_has_static_tls();
2991 if (optimized_type == tls::TLSOPT_NONE)
2993 // Create a GOT entry for the tp-relative offset.
2994 Output_data_got<64, false>* got
2995 = target->got_section(symtab, layout);
2996 got->add_global_with_rel(gsym, GOT_TYPE_TLS_OFFSET,
2997 target->rela_dyn_section(layout),
2998 elfcpp::R_X86_64_TPOFF64);
3000 else if (optimized_type != tls::TLSOPT_TO_LE)
3001 unsupported_reloc_global(object, r_type, gsym);
3004 case elfcpp::R_X86_64_TPOFF32: // Local-exec
3005 layout->set_has_static_tls();
3006 if (parameters->options().shared())
3007 unsupported_reloc_local(object, r_type);
3016 case elfcpp::R_X86_64_SIZE32:
3017 case elfcpp::R_X86_64_SIZE64:
3019 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
3020 object->name().c_str(), r_type,
3021 gsym->demangled_name().c_str());
3028 Target_x86_64<size>::gc_process_relocs(Symbol_table* symtab,
3030 Sized_relobj_file<size, false>* object,
3031 unsigned int data_shndx,
3032 unsigned int sh_type,
3033 const unsigned char* prelocs,
3035 Output_section* output_section,
3036 bool needs_special_offset_handling,
3037 size_t local_symbol_count,
3038 const unsigned char* plocal_symbols)
3041 if (sh_type == elfcpp::SHT_REL)
3046 gold::gc_process_relocs<size, false, Target_x86_64<size>, elfcpp::SHT_RELA,
3047 typename Target_x86_64<size>::Scan,
3048 typename Target_x86_64<size>::Relocatable_size_for_reloc>(
3057 needs_special_offset_handling,
3062 // Scan relocations for a section.
3066 Target_x86_64<size>::scan_relocs(Symbol_table* symtab,
3068 Sized_relobj_file<size, false>* object,
3069 unsigned int data_shndx,
3070 unsigned int sh_type,
3071 const unsigned char* prelocs,
3073 Output_section* output_section,
3074 bool needs_special_offset_handling,
3075 size_t local_symbol_count,
3076 const unsigned char* plocal_symbols)
3078 if (sh_type == elfcpp::SHT_REL)
3080 gold_error(_("%s: unsupported REL reloc section"),
3081 object->name().c_str());
3085 gold::scan_relocs<size, false, Target_x86_64<size>, elfcpp::SHT_RELA,
3086 typename Target_x86_64<size>::Scan>(
3095 needs_special_offset_handling,
3100 // Finalize the sections.
3104 Target_x86_64<size>::do_finalize_sections(
3106 const Input_objects*,
3107 Symbol_table* symtab)
3109 const Reloc_section* rel_plt = (this->plt_ == NULL
3111 : this->plt_->rela_plt());
3112 layout->add_target_dynamic_tags(false, this->got_plt_, rel_plt,
3113 this->rela_dyn_, true, false);
3115 // Fill in some more dynamic tags.
3116 Output_data_dynamic* const odyn = layout->dynamic_data();
3119 if (this->plt_ != NULL
3120 && this->plt_->output_section() != NULL
3121 && this->plt_->has_tlsdesc_entry())
3123 unsigned int plt_offset = this->plt_->get_tlsdesc_plt_offset();
3124 unsigned int got_offset = this->plt_->get_tlsdesc_got_offset();
3125 this->got_->finalize_data_size();
3126 odyn->add_section_plus_offset(elfcpp::DT_TLSDESC_PLT,
3127 this->plt_, plt_offset);
3128 odyn->add_section_plus_offset(elfcpp::DT_TLSDESC_GOT,
3129 this->got_, got_offset);
3133 // Emit any relocs we saved in an attempt to avoid generating COPY
3135 if (this->copy_relocs_.any_saved_relocs())
3136 this->copy_relocs_.emit(this->rela_dyn_section(layout));
3138 // Set the size of the _GLOBAL_OFFSET_TABLE_ symbol to the size of
3139 // the .got.plt section.
3140 Symbol* sym = this->global_offset_table_;
3143 uint64_t data_size = this->got_plt_->current_data_size();
3144 symtab->get_sized_symbol<size>(sym)->set_symsize(data_size);
3147 if (parameters->doing_static_link()
3148 && (this->plt_ == NULL || !this->plt_->has_irelative_section()))
3150 // If linking statically, make sure that the __rela_iplt symbols
3151 // were defined if necessary, even if we didn't create a PLT.
3152 static const Define_symbol_in_segment syms[] =
3155 "__rela_iplt_start", // name
3156 elfcpp::PT_LOAD, // segment_type
3157 elfcpp::PF_W, // segment_flags_set
3158 elfcpp::PF(0), // segment_flags_clear
3161 elfcpp::STT_NOTYPE, // type
3162 elfcpp::STB_GLOBAL, // binding
3163 elfcpp::STV_HIDDEN, // visibility
3165 Symbol::SEGMENT_START, // offset_from_base
3169 "__rela_iplt_end", // name
3170 elfcpp::PT_LOAD, // segment_type
3171 elfcpp::PF_W, // segment_flags_set
3172 elfcpp::PF(0), // segment_flags_clear
3175 elfcpp::STT_NOTYPE, // type
3176 elfcpp::STB_GLOBAL, // binding
3177 elfcpp::STV_HIDDEN, // visibility
3179 Symbol::SEGMENT_START, // offset_from_base
3184 symtab->define_symbols(layout, 2, syms,
3185 layout->script_options()->saw_sections_clause());
3189 // Perform a relocation.
3193 Target_x86_64<size>::Relocate::relocate(
3194 const Relocate_info<size, false>* relinfo,
3195 Target_x86_64<size>* target,
3198 const elfcpp::Rela<size, false>& rela,
3199 unsigned int r_type,
3200 const Sized_symbol<size>* gsym,
3201 const Symbol_value<size>* psymval,
3202 unsigned char* view,
3203 typename elfcpp::Elf_types<size>::Elf_Addr address,
3204 section_size_type view_size)
3206 if (this->skip_call_tls_get_addr_)
3208 if ((r_type != elfcpp::R_X86_64_PLT32
3209 && r_type != elfcpp::R_X86_64_PC32)
3211 || strcmp(gsym->name(), "__tls_get_addr") != 0)
3213 gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3214 _("missing expected TLS relocation"));
3218 this->skip_call_tls_get_addr_ = false;
3223 const Sized_relobj_file<size, false>* object = relinfo->object;
3225 // Pick the value to use for symbols defined in the PLT.
3226 Symbol_value<size> symval;
3228 && gsym->use_plt_offset(Scan::get_reference_flags(r_type)))
3230 symval.set_output_value(target->plt_address_for_global(gsym)
3231 + gsym->plt_offset());
3234 else if (gsym == NULL && psymval->is_ifunc_symbol())
3236 unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
3237 if (object->local_has_plt_offset(r_sym))
3239 symval.set_output_value(target->plt_address_for_local(object, r_sym)
3240 + object->local_plt_offset(r_sym));
3245 const elfcpp::Elf_Xword addend = rela.get_r_addend();
3247 // Get the GOT offset if needed.
3248 // The GOT pointer points to the end of the GOT section.
3249 // We need to subtract the size of the GOT section to get
3250 // the actual offset to use in the relocation.
3251 bool have_got_offset = false;
3252 unsigned int got_offset = 0;
3255 case elfcpp::R_X86_64_GOT32:
3256 case elfcpp::R_X86_64_GOT64:
3257 case elfcpp::R_X86_64_GOTPLT64:
3258 case elfcpp::R_X86_64_GOTPCREL:
3259 case elfcpp::R_X86_64_GOTPCREL64:
3262 gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
3263 got_offset = gsym->got_offset(GOT_TYPE_STANDARD) - target->got_size();
3267 unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
3268 gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD));
3269 got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD)
3270 - target->got_size());
3272 have_got_offset = true;
3281 case elfcpp::R_X86_64_NONE:
3282 case elfcpp::R_X86_64_GNU_VTINHERIT:
3283 case elfcpp::R_X86_64_GNU_VTENTRY:
3286 case elfcpp::R_X86_64_64:
3287 Relocate_functions<size, false>::rela64(view, object, psymval, addend);
3290 case elfcpp::R_X86_64_PC64:
3291 Relocate_functions<size, false>::pcrela64(view, object, psymval, addend,
3295 case elfcpp::R_X86_64_32:
3296 // FIXME: we need to verify that value + addend fits into 32 bits:
3297 // uint64_t x = value + addend;
3298 // x == static_cast<uint64_t>(static_cast<uint32_t>(x))
3299 // Likewise for other <=32-bit relocations (but see R_X86_64_32S).
3300 Relocate_functions<size, false>::rela32(view, object, psymval, addend);
3303 case elfcpp::R_X86_64_32S:
3304 // FIXME: we need to verify that value + addend fits into 32 bits:
3305 // int64_t x = value + addend; // note this quantity is signed!
3306 // x == static_cast<int64_t>(static_cast<int32_t>(x))
3307 Relocate_functions<size, false>::rela32(view, object, psymval, addend);
3310 case elfcpp::R_X86_64_PC32:
3311 Relocate_functions<size, false>::pcrela32(view, object, psymval, addend,
3315 case elfcpp::R_X86_64_16:
3316 Relocate_functions<size, false>::rela16(view, object, psymval, addend);
3319 case elfcpp::R_X86_64_PC16:
3320 Relocate_functions<size, false>::pcrela16(view, object, psymval, addend,
3324 case elfcpp::R_X86_64_8:
3325 Relocate_functions<size, false>::rela8(view, object, psymval, addend);
3328 case elfcpp::R_X86_64_PC8:
3329 Relocate_functions<size, false>::pcrela8(view, object, psymval, addend,
3333 case elfcpp::R_X86_64_PLT32:
3334 gold_assert(gsym == NULL
3335 || gsym->has_plt_offset()
3336 || gsym->final_value_is_known()
3337 || (gsym->is_defined()
3338 && !gsym->is_from_dynobj()
3339 && !gsym->is_preemptible()));
3340 // Note: while this code looks the same as for R_X86_64_PC32, it
3341 // behaves differently because psymval was set to point to
3342 // the PLT entry, rather than the symbol, in Scan::global().
3343 Relocate_functions<size, false>::pcrela32(view, object, psymval, addend,
3347 case elfcpp::R_X86_64_PLTOFF64:
3350 gold_assert(gsym->has_plt_offset()
3351 || gsym->final_value_is_known());
3352 typename elfcpp::Elf_types<size>::Elf_Addr got_address;
3353 got_address = target->got_section(NULL, NULL)->address();
3354 Relocate_functions<size, false>::rela64(view, object, psymval,
3355 addend - got_address);
3358 case elfcpp::R_X86_64_GOT32:
3359 gold_assert(have_got_offset);
3360 Relocate_functions<size, false>::rela32(view, got_offset, addend);
3363 case elfcpp::R_X86_64_GOTPC32:
3366 typename elfcpp::Elf_types<size>::Elf_Addr value;
3367 value = target->got_plt_section()->address();
3368 Relocate_functions<size, false>::pcrela32(view, value, addend, address);
3372 case elfcpp::R_X86_64_GOT64:
3373 // The ABI doc says "Like GOT64, but indicates a PLT entry is needed."
3374 // Since we always add a PLT entry, this is equivalent.
3375 case elfcpp::R_X86_64_GOTPLT64:
3376 gold_assert(have_got_offset);
3377 Relocate_functions<size, false>::rela64(view, got_offset, addend);
3380 case elfcpp::R_X86_64_GOTPC64:
3383 typename elfcpp::Elf_types<size>::Elf_Addr value;
3384 value = target->got_plt_section()->address();
3385 Relocate_functions<size, false>::pcrela64(view, value, addend, address);
3389 case elfcpp::R_X86_64_GOTOFF64:
3391 typename elfcpp::Elf_types<size>::Elf_Addr value;
3392 value = (psymval->value(object, 0)
3393 - target->got_plt_section()->address());
3394 Relocate_functions<size, false>::rela64(view, value, addend);
3398 case elfcpp::R_X86_64_GOTPCREL:
3400 gold_assert(have_got_offset);
3401 typename elfcpp::Elf_types<size>::Elf_Addr value;
3402 value = target->got_plt_section()->address() + got_offset;
3403 Relocate_functions<size, false>::pcrela32(view, value, addend, address);
3407 case elfcpp::R_X86_64_GOTPCREL64:
3409 gold_assert(have_got_offset);
3410 typename elfcpp::Elf_types<size>::Elf_Addr value;
3411 value = target->got_plt_section()->address() + got_offset;
3412 Relocate_functions<size, false>::pcrela64(view, value, addend, address);
3416 case elfcpp::R_X86_64_COPY:
3417 case elfcpp::R_X86_64_GLOB_DAT:
3418 case elfcpp::R_X86_64_JUMP_SLOT:
3419 case elfcpp::R_X86_64_RELATIVE:
3420 case elfcpp::R_X86_64_IRELATIVE:
3421 // These are outstanding tls relocs, which are unexpected when linking
3422 case elfcpp::R_X86_64_TPOFF64:
3423 case elfcpp::R_X86_64_DTPMOD64:
3424 case elfcpp::R_X86_64_TLSDESC:
3425 gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3426 _("unexpected reloc %u in object file"),
3430 // These are initial tls relocs, which are expected when linking
3431 case elfcpp::R_X86_64_TLSGD: // Global-dynamic
3432 case elfcpp::R_X86_64_GOTPC32_TLSDESC: // Global-dynamic (from ~oliva url)
3433 case elfcpp::R_X86_64_TLSDESC_CALL:
3434 case elfcpp::R_X86_64_TLSLD: // Local-dynamic
3435 case elfcpp::R_X86_64_DTPOFF32:
3436 case elfcpp::R_X86_64_DTPOFF64:
3437 case elfcpp::R_X86_64_GOTTPOFF: // Initial-exec
3438 case elfcpp::R_X86_64_TPOFF32: // Local-exec
3439 this->relocate_tls(relinfo, target, relnum, rela, r_type, gsym, psymval,
3440 view, address, view_size);
3443 case elfcpp::R_X86_64_SIZE32:
3444 case elfcpp::R_X86_64_SIZE64:
3446 gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3447 _("unsupported reloc %u"),
3455 // Perform a TLS relocation.
3459 Target_x86_64<size>::Relocate::relocate_tls(
3460 const Relocate_info<size, false>* relinfo,
3461 Target_x86_64<size>* target,
3463 const elfcpp::Rela<size, false>& rela,
3464 unsigned int r_type,
3465 const Sized_symbol<size>* gsym,
3466 const Symbol_value<size>* psymval,
3467 unsigned char* view,
3468 typename elfcpp::Elf_types<size>::Elf_Addr address,
3469 section_size_type view_size)
3471 Output_segment* tls_segment = relinfo->layout->tls_segment();
3473 const Sized_relobj_file<size, false>* object = relinfo->object;
3474 const elfcpp::Elf_Xword addend = rela.get_r_addend();
3475 elfcpp::Shdr<size, false> data_shdr(relinfo->data_shdr);
3476 bool is_executable = (data_shdr.get_sh_flags() & elfcpp::SHF_EXECINSTR) != 0;
3478 typename elfcpp::Elf_types<size>::Elf_Addr value = psymval->value(relinfo->object, 0);
3480 const bool is_final = (gsym == NULL
3481 ? !parameters->options().shared()
3482 : gsym->final_value_is_known());
3483 tls::Tls_optimization optimized_type
3484 = Target_x86_64<size>::optimize_tls_reloc(is_final, r_type);
3487 case elfcpp::R_X86_64_TLSGD: // Global-dynamic
3488 if (!is_executable && optimized_type == tls::TLSOPT_TO_LE)
3490 // If this code sequence is used in a non-executable section,
3491 // we will not optimize the R_X86_64_DTPOFF32/64 relocation,
3492 // on the assumption that it's being used by itself in a debug
3493 // section. Therefore, in the unlikely event that the code
3494 // sequence appears in a non-executable section, we simply
3495 // leave it unoptimized.
3496 optimized_type = tls::TLSOPT_NONE;
3498 if (optimized_type == tls::TLSOPT_TO_LE)
3500 if (tls_segment == NULL)
3502 gold_assert(parameters->errors()->error_count() > 0
3503 || issue_undefined_symbol_error(gsym));
3506 this->tls_gd_to_le(relinfo, relnum, tls_segment,
3507 rela, r_type, value, view,
3513 unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE
3514 ? GOT_TYPE_TLS_OFFSET
3515 : GOT_TYPE_TLS_PAIR);
3516 unsigned int got_offset;
3519 gold_assert(gsym->has_got_offset(got_type));
3520 got_offset = gsym->got_offset(got_type) - target->got_size();
3524 unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
3525 gold_assert(object->local_has_got_offset(r_sym, got_type));
3526 got_offset = (object->local_got_offset(r_sym, got_type)
3527 - target->got_size());
3529 if (optimized_type == tls::TLSOPT_TO_IE)
3531 value = target->got_plt_section()->address() + got_offset;
3532 this->tls_gd_to_ie(relinfo, relnum, tls_segment, rela, r_type,
3533 value, view, address, view_size);
3536 else if (optimized_type == tls::TLSOPT_NONE)
3538 // Relocate the field with the offset of the pair of GOT
3540 value = target->got_plt_section()->address() + got_offset;
3541 Relocate_functions<size, false>::pcrela32(view, value, addend,
3546 gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3547 _("unsupported reloc %u"), r_type);
3550 case elfcpp::R_X86_64_GOTPC32_TLSDESC: // Global-dynamic (from ~oliva url)
3551 case elfcpp::R_X86_64_TLSDESC_CALL:
3552 if (!is_executable && optimized_type == tls::TLSOPT_TO_LE)
3554 // See above comment for R_X86_64_TLSGD.
3555 optimized_type = tls::TLSOPT_NONE;
3557 if (optimized_type == tls::TLSOPT_TO_LE)
3559 if (tls_segment == NULL)
3561 gold_assert(parameters->errors()->error_count() > 0
3562 || issue_undefined_symbol_error(gsym));
3565 this->tls_desc_gd_to_le(relinfo, relnum, tls_segment,
3566 rela, r_type, value, view,
3572 unsigned int got_type = (optimized_type == tls::TLSOPT_TO_IE
3573 ? GOT_TYPE_TLS_OFFSET
3574 : GOT_TYPE_TLS_DESC);
3575 unsigned int got_offset = 0;
3576 if (r_type == elfcpp::R_X86_64_GOTPC32_TLSDESC
3577 && optimized_type == tls::TLSOPT_NONE)
3579 // We created GOT entries in the .got.tlsdesc portion of
3580 // the .got.plt section, but the offset stored in the
3581 // symbol is the offset within .got.tlsdesc.
3582 got_offset = (target->got_size()
3583 + target->got_plt_section()->data_size());
3587 gold_assert(gsym->has_got_offset(got_type));
3588 got_offset += gsym->got_offset(got_type) - target->got_size();
3592 unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
3593 gold_assert(object->local_has_got_offset(r_sym, got_type));
3594 got_offset += (object->local_got_offset(r_sym, got_type)
3595 - target->got_size());
3597 if (optimized_type == tls::TLSOPT_TO_IE)
3599 if (tls_segment == NULL)
3601 gold_assert(parameters->errors()->error_count() > 0
3602 || issue_undefined_symbol_error(gsym));
3605 value = target->got_plt_section()->address() + got_offset;
3606 this->tls_desc_gd_to_ie(relinfo, relnum, tls_segment,
3607 rela, r_type, value, view, address,
3611 else if (optimized_type == tls::TLSOPT_NONE)
3613 if (r_type == elfcpp::R_X86_64_GOTPC32_TLSDESC)
3615 // Relocate the field with the offset of the pair of GOT
3617 value = target->got_plt_section()->address() + got_offset;
3618 Relocate_functions<size, false>::pcrela32(view, value, addend,
3624 gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3625 _("unsupported reloc %u"), r_type);
3628 case elfcpp::R_X86_64_TLSLD: // Local-dynamic
3629 if (!is_executable && optimized_type == tls::TLSOPT_TO_LE)
3631 // See above comment for R_X86_64_TLSGD.
3632 optimized_type = tls::TLSOPT_NONE;
3634 if (optimized_type == tls::TLSOPT_TO_LE)
3636 if (tls_segment == NULL)
3638 gold_assert(parameters->errors()->error_count() > 0
3639 || issue_undefined_symbol_error(gsym));
3642 this->tls_ld_to_le(relinfo, relnum, tls_segment, rela, r_type,
3643 value, view, view_size);
3646 else if (optimized_type == tls::TLSOPT_NONE)
3648 // Relocate the field with the offset of the GOT entry for
3649 // the module index.
3650 unsigned int got_offset;
3651 got_offset = (target->got_mod_index_entry(NULL, NULL, NULL)
3652 - target->got_size());
3653 value = target->got_plt_section()->address() + got_offset;
3654 Relocate_functions<size, false>::pcrela32(view, value, addend,
3658 gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3659 _("unsupported reloc %u"), r_type);
3662 case elfcpp::R_X86_64_DTPOFF32:
3663 // This relocation type is used in debugging information.
3664 // In that case we need to not optimize the value. If the
3665 // section is not executable, then we assume we should not
3666 // optimize this reloc. See comments above for R_X86_64_TLSGD,
3667 // R_X86_64_GOTPC32_TLSDESC, R_X86_64_TLSDESC_CALL, and
3669 if (optimized_type == tls::TLSOPT_TO_LE && is_executable)
3671 if (tls_segment == NULL)
3673 gold_assert(parameters->errors()->error_count() > 0
3674 || issue_undefined_symbol_error(gsym));
3677 value -= tls_segment->memsz();
3679 Relocate_functions<size, false>::rela32(view, value, addend);
3682 case elfcpp::R_X86_64_DTPOFF64:
3683 // See R_X86_64_DTPOFF32, just above, for why we check for is_executable.
3684 if (optimized_type == tls::TLSOPT_TO_LE && is_executable)
3686 if (tls_segment == NULL)
3688 gold_assert(parameters->errors()->error_count() > 0
3689 || issue_undefined_symbol_error(gsym));
3692 value -= tls_segment->memsz();
3694 Relocate_functions<size, false>::rela64(view, value, addend);
3697 case elfcpp::R_X86_64_GOTTPOFF: // Initial-exec
3698 if (optimized_type == tls::TLSOPT_TO_LE)
3700 if (tls_segment == NULL)
3702 gold_assert(parameters->errors()->error_count() > 0
3703 || issue_undefined_symbol_error(gsym));
3706 Target_x86_64<size>::Relocate::tls_ie_to_le(relinfo, relnum,
3708 r_type, value, view,
3712 else if (optimized_type == tls::TLSOPT_NONE)
3714 // Relocate the field with the offset of the GOT entry for
3715 // the tp-relative offset of the symbol.
3716 unsigned int got_offset;
3719 gold_assert(gsym->has_got_offset(GOT_TYPE_TLS_OFFSET));
3720 got_offset = (gsym->got_offset(GOT_TYPE_TLS_OFFSET)
3721 - target->got_size());
3725 unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
3726 gold_assert(object->local_has_got_offset(r_sym,
3727 GOT_TYPE_TLS_OFFSET));
3728 got_offset = (object->local_got_offset(r_sym, GOT_TYPE_TLS_OFFSET)
3729 - target->got_size());
3731 value = target->got_plt_section()->address() + got_offset;
3732 Relocate_functions<size, false>::pcrela32(view, value, addend,
3736 gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
3737 _("unsupported reloc type %u"),
3741 case elfcpp::R_X86_64_TPOFF32: // Local-exec
3742 if (tls_segment == NULL)
3744 gold_assert(parameters->errors()->error_count() > 0
3745 || issue_undefined_symbol_error(gsym));
3748 value -= tls_segment->memsz();
3749 Relocate_functions<size, false>::rela32(view, value, addend);
3754 // Do a relocation in which we convert a TLS General-Dynamic to an
3759 Target_x86_64<size>::Relocate::tls_gd_to_ie(
3760 const Relocate_info<size, false>* relinfo,
3763 const elfcpp::Rela<size, false>& rela,
3765 typename elfcpp::Elf_types<size>::Elf_Addr value,
3766 unsigned char* view,
3767 typename elfcpp::Elf_types<size>::Elf_Addr address,
3768 section_size_type view_size)
3771 // .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
3772 // .word 0x6666; rex64; call __tls_get_addr
3773 // ==> movq %fs:0,%rax; addq x@gottpoff(%rip),%rax
3775 // leaq foo@tlsgd(%rip),%rdi;
3776 // .word 0x6666; rex64; call __tls_get_addr
3777 // ==> movl %fs:0,%eax; addq x@gottpoff(%rip),%rax
3779 tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 12);
3780 tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3781 (memcmp(view + 4, "\x66\x66\x48\xe8", 4) == 0));
3785 tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size,
3787 tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3788 (memcmp(view - 4, "\x66\x48\x8d\x3d", 4) == 0));
3789 memcpy(view - 4, "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x03\x05\0\0\0\0",
3794 tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size,
3796 tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3797 (memcmp(view - 3, "\x48\x8d\x3d", 3) == 0));
3798 memcpy(view - 3, "\x64\x8b\x04\x25\0\0\0\0\x48\x03\x05\0\0\0\0",
3802 const elfcpp::Elf_Xword addend = rela.get_r_addend();
3803 Relocate_functions<size, false>::pcrela32(view + 8, value, addend - 8,
3806 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3808 this->skip_call_tls_get_addr_ = true;
3811 // Do a relocation in which we convert a TLS General-Dynamic to a
3816 Target_x86_64<size>::Relocate::tls_gd_to_le(
3817 const Relocate_info<size, false>* relinfo,
3819 Output_segment* tls_segment,
3820 const elfcpp::Rela<size, false>& rela,
3822 typename elfcpp::Elf_types<size>::Elf_Addr value,
3823 unsigned char* view,
3824 section_size_type view_size)
3827 // .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
3828 // .word 0x6666; rex64; call __tls_get_addr
3829 // ==> movq %fs:0,%rax; leaq x@tpoff(%rax),%rax
3831 // leaq foo@tlsgd(%rip),%rdi;
3832 // .word 0x6666; rex64; call __tls_get_addr
3833 // ==> movl %fs:0,%eax; leaq x@tpoff(%rax),%rax
3835 tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 12);
3836 tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3837 (memcmp(view + 4, "\x66\x66\x48\xe8", 4) == 0));
3841 tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size,
3843 tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3844 (memcmp(view - 4, "\x66\x48\x8d\x3d", 4) == 0));
3845 memcpy(view - 4, "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0\0",
3850 tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size,
3852 tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3853 (memcmp(view - 3, "\x48\x8d\x3d", 3) == 0));
3855 memcpy(view - 3, "\x64\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0\0",
3859 value -= tls_segment->memsz();
3860 Relocate_functions<size, false>::rela32(view + 8, value, 0);
3862 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3864 this->skip_call_tls_get_addr_ = true;
3867 // Do a TLSDESC-style General-Dynamic to Initial-Exec transition.
3871 Target_x86_64<size>::Relocate::tls_desc_gd_to_ie(
3872 const Relocate_info<size, false>* relinfo,
3875 const elfcpp::Rela<size, false>& rela,
3876 unsigned int r_type,
3877 typename elfcpp::Elf_types<size>::Elf_Addr value,
3878 unsigned char* view,
3879 typename elfcpp::Elf_types<size>::Elf_Addr address,
3880 section_size_type view_size)
3882 if (r_type == elfcpp::R_X86_64_GOTPC32_TLSDESC)
3884 // leaq foo@tlsdesc(%rip), %rax
3885 // ==> movq foo@gottpoff(%rip), %rax
3886 tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -3);
3887 tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 4);
3888 tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3889 view[-3] == 0x48 && view[-2] == 0x8d && view[-1] == 0x05);
3891 const elfcpp::Elf_Xword addend = rela.get_r_addend();
3892 Relocate_functions<size, false>::pcrela32(view, value, addend, address);
3896 // call *foo@tlscall(%rax)
3898 gold_assert(r_type == elfcpp::R_X86_64_TLSDESC_CALL);
3899 tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 2);
3900 tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3901 view[0] == 0xff && view[1] == 0x10);
3907 // Do a TLSDESC-style General-Dynamic to Local-Exec transition.
3911 Target_x86_64<size>::Relocate::tls_desc_gd_to_le(
3912 const Relocate_info<size, false>* relinfo,
3914 Output_segment* tls_segment,
3915 const elfcpp::Rela<size, false>& rela,
3916 unsigned int r_type,
3917 typename elfcpp::Elf_types<size>::Elf_Addr value,
3918 unsigned char* view,
3919 section_size_type view_size)
3921 if (r_type == elfcpp::R_X86_64_GOTPC32_TLSDESC)
3923 // leaq foo@tlsdesc(%rip), %rax
3924 // ==> movq foo@tpoff, %rax
3925 tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -3);
3926 tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 4);
3927 tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3928 view[-3] == 0x48 && view[-2] == 0x8d && view[-1] == 0x05);
3931 value -= tls_segment->memsz();
3932 Relocate_functions<size, false>::rela32(view, value, 0);
3936 // call *foo@tlscall(%rax)
3938 gold_assert(r_type == elfcpp::R_X86_64_TLSDESC_CALL);
3939 tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 2);
3940 tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3941 view[0] == 0xff && view[1] == 0x10);
3949 Target_x86_64<size>::Relocate::tls_ld_to_le(
3950 const Relocate_info<size, false>* relinfo,
3953 const elfcpp::Rela<size, false>& rela,
3955 typename elfcpp::Elf_types<size>::Elf_Addr,
3956 unsigned char* view,
3957 section_size_type view_size)
3959 // leaq foo@tlsld(%rip),%rdi; call __tls_get_addr@plt;
3960 // ... leq foo@dtpoff(%rax),%reg
3961 // ==> .word 0x6666; .byte 0x66; movq %fs:0,%rax ... leaq x@tpoff(%rax),%rdx
3963 tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -3);
3964 tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 9);
3966 tls::check_tls(relinfo, relnum, rela.get_r_offset(),
3967 view[-3] == 0x48 && view[-2] == 0x8d && view[-1] == 0x3d);
3969 tls::check_tls(relinfo, relnum, rela.get_r_offset(), view[4] == 0xe8);
3971 memcpy(view - 3, "\x66\x66\x66\x64\x48\x8b\x04\x25\0\0\0\0", 12);
3973 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3975 this->skip_call_tls_get_addr_ = true;
3978 // Do a relocation in which we convert a TLS Initial-Exec to a
3983 Target_x86_64<size>::Relocate::tls_ie_to_le(
3984 const Relocate_info<size, false>* relinfo,
3986 Output_segment* tls_segment,
3987 const elfcpp::Rela<size, false>& rela,
3989 typename elfcpp::Elf_types<size>::Elf_Addr value,
3990 unsigned char* view,
3991 section_size_type view_size)
3993 // We need to examine the opcodes to figure out which instruction we
3996 // movq foo@gottpoff(%rip),%reg ==> movq $YY,%reg
3997 // addq foo@gottpoff(%rip),%reg ==> addq $YY,%reg
3999 tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, -3);
4000 tls::check_range(relinfo, relnum, rela.get_r_offset(), view_size, 4);
4002 unsigned char op1 = view[-3];
4003 unsigned char op2 = view[-2];
4004 unsigned char op3 = view[-1];
4005 unsigned char reg = op3 >> 3;
4013 view[-1] = 0xc0 | reg;
4017 // Special handling for %rsp.
4021 view[-1] = 0xc0 | reg;
4029 view[-1] = 0x80 | reg | (reg << 3);
4032 value -= tls_segment->memsz();
4033 Relocate_functions<size, false>::rela32(view, value, 0);
4036 // Relocate section data.
4040 Target_x86_64<size>::relocate_section(
4041 const Relocate_info<size, false>* relinfo,
4042 unsigned int sh_type,
4043 const unsigned char* prelocs,
4045 Output_section* output_section,
4046 bool needs_special_offset_handling,
4047 unsigned char* view,
4048 typename elfcpp::Elf_types<size>::Elf_Addr address,
4049 section_size_type view_size,
4050 const Reloc_symbol_changes* reloc_symbol_changes)
4052 gold_assert(sh_type == elfcpp::SHT_RELA);
4054 gold::relocate_section<size, false, Target_x86_64<size>, elfcpp::SHT_RELA,
4055 typename Target_x86_64<size>::Relocate>(
4061 needs_special_offset_handling,
4065 reloc_symbol_changes);
4068 // Apply an incremental relocation. Incremental relocations always refer
4069 // to global symbols.
4073 Target_x86_64<size>::apply_relocation(
4074 const Relocate_info<size, false>* relinfo,
4075 typename elfcpp::Elf_types<size>::Elf_Addr r_offset,
4076 unsigned int r_type,
4077 typename elfcpp::Elf_types<size>::Elf_Swxword r_addend,
4079 unsigned char* view,
4080 typename elfcpp::Elf_types<size>::Elf_Addr address,
4081 section_size_type view_size)
4083 gold::apply_relocation<size, false, Target_x86_64<size>,
4084 typename Target_x86_64<size>::Relocate>(
4096 // Return the size of a relocation while scanning during a relocatable
4101 Target_x86_64<size>::Relocatable_size_for_reloc::get_size_for_reloc(
4102 unsigned int r_type,
4107 case elfcpp::R_X86_64_NONE:
4108 case elfcpp::R_X86_64_GNU_VTINHERIT:
4109 case elfcpp::R_X86_64_GNU_VTENTRY:
4110 case elfcpp::R_X86_64_TLSGD: // Global-dynamic
4111 case elfcpp::R_X86_64_GOTPC32_TLSDESC: // Global-dynamic (from ~oliva url)
4112 case elfcpp::R_X86_64_TLSDESC_CALL:
4113 case elfcpp::R_X86_64_TLSLD: // Local-dynamic
4114 case elfcpp::R_X86_64_DTPOFF32:
4115 case elfcpp::R_X86_64_DTPOFF64:
4116 case elfcpp::R_X86_64_GOTTPOFF: // Initial-exec
4117 case elfcpp::R_X86_64_TPOFF32: // Local-exec
4120 case elfcpp::R_X86_64_64:
4121 case elfcpp::R_X86_64_PC64:
4122 case elfcpp::R_X86_64_GOTOFF64:
4123 case elfcpp::R_X86_64_GOTPC64:
4124 case elfcpp::R_X86_64_PLTOFF64:
4125 case elfcpp::R_X86_64_GOT64:
4126 case elfcpp::R_X86_64_GOTPCREL64:
4127 case elfcpp::R_X86_64_GOTPCREL:
4128 case elfcpp::R_X86_64_GOTPLT64:
4131 case elfcpp::R_X86_64_32:
4132 case elfcpp::R_X86_64_32S:
4133 case elfcpp::R_X86_64_PC32:
4134 case elfcpp::R_X86_64_PLT32:
4135 case elfcpp::R_X86_64_GOTPC32:
4136 case elfcpp::R_X86_64_GOT32:
4139 case elfcpp::R_X86_64_16:
4140 case elfcpp::R_X86_64_PC16:
4143 case elfcpp::R_X86_64_8:
4144 case elfcpp::R_X86_64_PC8:
4147 case elfcpp::R_X86_64_COPY:
4148 case elfcpp::R_X86_64_GLOB_DAT:
4149 case elfcpp::R_X86_64_JUMP_SLOT:
4150 case elfcpp::R_X86_64_RELATIVE:
4151 case elfcpp::R_X86_64_IRELATIVE:
4152 // These are outstanding tls relocs, which are unexpected when linking
4153 case elfcpp::R_X86_64_TPOFF64:
4154 case elfcpp::R_X86_64_DTPMOD64:
4155 case elfcpp::R_X86_64_TLSDESC:
4156 object->error(_("unexpected reloc %u in object file"), r_type);
4159 case elfcpp::R_X86_64_SIZE32:
4160 case elfcpp::R_X86_64_SIZE64:
4162 object->error(_("unsupported reloc %u against local symbol"), r_type);
4167 // Scan the relocs during a relocatable link.
4171 Target_x86_64<size>::scan_relocatable_relocs(
4172 Symbol_table* symtab,
4174 Sized_relobj_file<size, false>* object,
4175 unsigned int data_shndx,
4176 unsigned int sh_type,
4177 const unsigned char* prelocs,
4179 Output_section* output_section,
4180 bool needs_special_offset_handling,
4181 size_t local_symbol_count,
4182 const unsigned char* plocal_symbols,
4183 Relocatable_relocs* rr)
4185 gold_assert(sh_type == elfcpp::SHT_RELA);
4187 typedef gold::Default_scan_relocatable_relocs<elfcpp::SHT_RELA,
4188 Relocatable_size_for_reloc> Scan_relocatable_relocs;
4190 gold::scan_relocatable_relocs<size, false, elfcpp::SHT_RELA,
4191 Scan_relocatable_relocs>(
4199 needs_special_offset_handling,
4205 // Relocate a section during a relocatable link.
4209 Target_x86_64<size>::relocate_for_relocatable(
4210 const Relocate_info<size, false>* relinfo,
4211 unsigned int sh_type,
4212 const unsigned char* prelocs,
4214 Output_section* output_section,
4215 off_t offset_in_output_section,
4216 const Relocatable_relocs* rr,
4217 unsigned char* view,
4218 typename elfcpp::Elf_types<size>::Elf_Addr view_address,
4219 section_size_type view_size,
4220 unsigned char* reloc_view,
4221 section_size_type reloc_view_size)
4223 gold_assert(sh_type == elfcpp::SHT_RELA);
4225 gold::relocate_for_relocatable<size, false, elfcpp::SHT_RELA>(
4230 offset_in_output_section,
4239 // Return the value to use for a dynamic which requires special
4240 // treatment. This is how we support equality comparisons of function
4241 // pointers across shared library boundaries, as described in the
4242 // processor specific ABI supplement.
4246 Target_x86_64<size>::do_dynsym_value(const Symbol* gsym) const
4248 gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset());
4249 return this->plt_address_for_global(gsym) + gsym->plt_offset();
4252 // Return a string used to fill a code section with nops to take up
4253 // the specified length.
4257 Target_x86_64<size>::do_code_fill(section_size_type length) const
4261 // Build a jmpq instruction to skip over the bytes.
4262 unsigned char jmp[5];
4264 elfcpp::Swap_unaligned<32, false>::writeval(jmp + 1, length - 5);
4265 return (std::string(reinterpret_cast<char*>(&jmp[0]), 5)
4266 + std::string(length - 5, static_cast<char>(0x90)));
4269 // Nop sequences of various lengths.
4270 const char nop1[1] = { '\x90' }; // nop
4271 const char nop2[2] = { '\x66', '\x90' }; // xchg %ax %ax
4272 const char nop3[3] = { '\x0f', '\x1f', '\x00' }; // nop (%rax)
4273 const char nop4[4] = { '\x0f', '\x1f', '\x40', // nop 0(%rax)
4275 const char nop5[5] = { '\x0f', '\x1f', '\x44', // nop 0(%rax,%rax,1)
4277 const char nop6[6] = { '\x66', '\x0f', '\x1f', // nopw 0(%rax,%rax,1)
4278 '\x44', '\x00', '\x00' };
4279 const char nop7[7] = { '\x0f', '\x1f', '\x80', // nopl 0L(%rax)
4280 '\x00', '\x00', '\x00',
4282 const char nop8[8] = { '\x0f', '\x1f', '\x84', // nopl 0L(%rax,%rax,1)
4283 '\x00', '\x00', '\x00',
4285 const char nop9[9] = { '\x66', '\x0f', '\x1f', // nopw 0L(%rax,%rax,1)
4286 '\x84', '\x00', '\x00',
4287 '\x00', '\x00', '\x00' };
4288 const char nop10[10] = { '\x66', '\x2e', '\x0f', // nopw %cs:0L(%rax,%rax,1)
4289 '\x1f', '\x84', '\x00',
4290 '\x00', '\x00', '\x00',
4292 const char nop11[11] = { '\x66', '\x66', '\x2e', // data16
4293 '\x0f', '\x1f', '\x84', // nopw %cs:0L(%rax,%rax,1)
4294 '\x00', '\x00', '\x00',
4296 const char nop12[12] = { '\x66', '\x66', '\x66', // data16; data16
4297 '\x2e', '\x0f', '\x1f', // nopw %cs:0L(%rax,%rax,1)
4298 '\x84', '\x00', '\x00',
4299 '\x00', '\x00', '\x00' };
4300 const char nop13[13] = { '\x66', '\x66', '\x66', // data16; data16; data16
4301 '\x66', '\x2e', '\x0f', // nopw %cs:0L(%rax,%rax,1)
4302 '\x1f', '\x84', '\x00',
4303 '\x00', '\x00', '\x00',
4305 const char nop14[14] = { '\x66', '\x66', '\x66', // data16; data16; data16
4306 '\x66', '\x66', '\x2e', // data16
4307 '\x0f', '\x1f', '\x84', // nopw %cs:0L(%rax,%rax,1)
4308 '\x00', '\x00', '\x00',
4310 const char nop15[15] = { '\x66', '\x66', '\x66', // data16; data16; data16
4311 '\x66', '\x66', '\x66', // data16; data16
4312 '\x2e', '\x0f', '\x1f', // nopw %cs:0L(%rax,%rax,1)
4313 '\x84', '\x00', '\x00',
4314 '\x00', '\x00', '\x00' };
4316 const char* nops[16] = {
4318 nop1, nop2, nop3, nop4, nop5, nop6, nop7,
4319 nop8, nop9, nop10, nop11, nop12, nop13, nop14, nop15
4322 return std::string(nops[length], length);
4325 // Return the addend to use for a target specific relocation. The
4326 // only target specific relocation is R_X86_64_TLSDESC for a local
4327 // symbol. We want to set the addend is the offset of the local
4328 // symbol in the TLS segment.
4332 Target_x86_64<size>::do_reloc_addend(void* arg, unsigned int r_type,
4335 gold_assert(r_type == elfcpp::R_X86_64_TLSDESC);
4336 uintptr_t intarg = reinterpret_cast<uintptr_t>(arg);
4337 gold_assert(intarg < this->tlsdesc_reloc_info_.size());
4338 const Tlsdesc_info& ti(this->tlsdesc_reloc_info_[intarg]);
4339 const Symbol_value<size>* psymval = ti.object->local_symbol(ti.r_sym);
4340 gold_assert(psymval->is_tls_symbol());
4341 // The value of a TLS symbol is the offset in the TLS segment.
4342 return psymval->value(ti.object, 0);
4345 // Return the value to use for the base of a DW_EH_PE_datarel offset
4346 // in an FDE. Solaris and SVR4 use DW_EH_PE_datarel because their
4347 // assembler can not write out the difference between two labels in
4348 // different sections, so instead of using a pc-relative value they
4349 // use an offset from the GOT.
4353 Target_x86_64<size>::do_ehframe_datarel_base() const
4355 gold_assert(this->global_offset_table_ != NULL);
4356 Symbol* sym = this->global_offset_table_;
4357 Sized_symbol<size>* ssym = static_cast<Sized_symbol<size>*>(sym);
4358 return ssym->value();
4361 // FNOFFSET in section SHNDX in OBJECT is the start of a function
4362 // compiled with -fsplit-stack. The function calls non-split-stack
4363 // code. We have to change the function so that it always ensures
4364 // that it has enough stack space to run some random function.
4368 Target_x86_64<size>::do_calls_non_split(Relobj* object, unsigned int shndx,
4369 section_offset_type fnoffset,
4370 section_size_type fnsize,
4371 unsigned char* view,
4372 section_size_type view_size,
4374 std::string* to) const
4376 // The function starts with a comparison of the stack pointer and a
4377 // field in the TCB. This is followed by a jump.
4380 if (this->match_view(view, view_size, fnoffset, "\x64\x48\x3b\x24\x25", 5)
4383 // We will call __morestack if the carry flag is set after this
4384 // comparison. We turn the comparison into an stc instruction
4386 view[fnoffset] = '\xf9';
4387 this->set_view_to_nop(view, view_size, fnoffset + 1, 8);
4389 // lea NN(%rsp),%r10
4390 // lea NN(%rsp),%r11
4391 else if ((this->match_view(view, view_size, fnoffset,
4392 "\x4c\x8d\x94\x24", 4)
4393 || this->match_view(view, view_size, fnoffset,
4394 "\x4c\x8d\x9c\x24", 4))
4397 // This is loading an offset from the stack pointer for a
4398 // comparison. The offset is negative, so we decrease the
4399 // offset by the amount of space we need for the stack. This
4400 // means we will avoid calling __morestack if there happens to
4401 // be plenty of space on the stack already.
4402 unsigned char* pval = view + fnoffset + 4;
4403 uint32_t val = elfcpp::Swap_unaligned<32, false>::readval(pval);
4404 val -= parameters->options().split_stack_adjust_size();
4405 elfcpp::Swap_unaligned<32, false>::writeval(pval, val);
4409 if (!object->has_no_split_stack())
4410 object->error(_("failed to match split-stack sequence at "
4411 "section %u offset %0zx"),
4412 shndx, static_cast<size_t>(fnoffset));
4416 // We have to change the function so that it calls
4417 // __morestack_non_split instead of __morestack. The former will
4418 // allocate additional stack space.
4419 *from = "__morestack";
4420 *to = "__morestack_non_split";
4423 // The selector for x86_64 object files. Note this is never instantiated
4424 // directly. It's only used in Target_selector_x86_64_nacl, below.
4427 class Target_selector_x86_64 : public Target_selector_freebsd
4430 Target_selector_x86_64()
4431 : Target_selector_freebsd(elfcpp::EM_X86_64, size, false,
4433 ? "elf64-x86-64" : "elf32-x86-64"),
4435 ? "elf64-x86-64-freebsd"
4436 : "elf32-x86-64-freebsd"),
4437 (size == 64 ? "elf_x86_64" : "elf32_x86_64"))
4441 do_instantiate_target()
4442 { return new Target_x86_64<size>(); }
4446 // NaCl variant. It uses different PLT contents.
4449 class Output_data_plt_x86_64_nacl : public Output_data_plt_x86_64<size>
4452 Output_data_plt_x86_64_nacl(Layout* layout,
4453 Output_data_got<64, false>* got,
4454 Output_data_space* got_plt,
4455 Output_data_space* got_irelative)
4456 : Output_data_plt_x86_64<size>(layout, plt_entry_size,
4457 got, got_plt, got_irelative)
4460 Output_data_plt_x86_64_nacl(Layout* layout,
4461 Output_data_got<64, false>* got,
4462 Output_data_space* got_plt,
4463 Output_data_space* got_irelative,
4464 unsigned int plt_count)
4465 : Output_data_plt_x86_64<size>(layout, plt_entry_size,
4466 got, got_plt, got_irelative,
4471 virtual unsigned int
4472 do_get_plt_entry_size() const
4473 { return plt_entry_size; }
4476 do_add_eh_frame(Layout* layout)
4478 layout->add_eh_frame_for_plt(this,
4479 this->plt_eh_frame_cie,
4480 this->plt_eh_frame_cie_size,
4482 plt_eh_frame_fde_size);
4486 do_fill_first_plt_entry(unsigned char* pov,
4487 typename elfcpp::Elf_types<size>::Elf_Addr got_addr,
4488 typename elfcpp::Elf_types<size>::Elf_Addr plt_addr);
4490 virtual unsigned int
4491 do_fill_plt_entry(unsigned char* pov,
4492 typename elfcpp::Elf_types<size>::Elf_Addr got_address,
4493 typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
4494 unsigned int got_offset,
4495 unsigned int plt_offset,
4496 unsigned int plt_index);
4499 do_fill_tlsdesc_entry(unsigned char* pov,
4500 typename elfcpp::Elf_types<size>::Elf_Addr got_address,
4501 typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
4502 typename elfcpp::Elf_types<size>::Elf_Addr got_base,
4503 unsigned int tlsdesc_got_offset,
4504 unsigned int plt_offset);
4507 // The size of an entry in the PLT.
4508 static const int plt_entry_size = 64;
4510 // The first entry in the PLT.
4511 static const unsigned char first_plt_entry[plt_entry_size];
4513 // Other entries in the PLT for an executable.
4514 static const unsigned char plt_entry[plt_entry_size];
4516 // The reserved TLSDESC entry in the PLT for an executable.
4517 static const unsigned char tlsdesc_plt_entry[plt_entry_size];
4519 // The .eh_frame unwind information for the PLT.
4520 static const int plt_eh_frame_fde_size = 32;
4521 static const unsigned char plt_eh_frame_fde[plt_eh_frame_fde_size];
4525 class Target_x86_64_nacl : public Target_x86_64<size>
4528 Target_x86_64_nacl()
4529 : Target_x86_64<size>(&x86_64_nacl_info)
4532 virtual Output_data_plt_x86_64<size>*
4533 do_make_data_plt(Layout* layout,
4534 Output_data_got<64, false>* got,
4535 Output_data_space* got_plt,
4536 Output_data_space* got_irelative)
4538 return new Output_data_plt_x86_64_nacl<size>(layout, got, got_plt,
4542 virtual Output_data_plt_x86_64<size>*
4543 do_make_data_plt(Layout* layout,
4544 Output_data_got<64, false>* got,
4545 Output_data_space* got_plt,
4546 Output_data_space* got_irelative,
4547 unsigned int plt_count)
4549 return new Output_data_plt_x86_64_nacl<size>(layout, got, got_plt,
4555 static const Target::Target_info x86_64_nacl_info;
4559 const Target::Target_info Target_x86_64_nacl<64>::x86_64_nacl_info =
4562 false, // is_big_endian
4563 elfcpp::EM_X86_64, // machine_code
4564 false, // has_make_symbol
4565 false, // has_resolve
4566 true, // has_code_fill
4567 true, // is_default_stack_executable
4568 true, // can_icf_inline_merge_sections
4570 "/lib64/ld-nacl-x86-64.so.1", // dynamic_linker
4571 0x20000, // default_text_segment_address
4572 0x10000, // abi_pagesize (overridable by -z max-page-size)
4573 0x10000, // common_pagesize (overridable by -z common-page-size)
4574 true, // isolate_execinstr
4575 0x10000000, // rosegment_gap
4576 elfcpp::SHN_UNDEF, // small_common_shndx
4577 elfcpp::SHN_X86_64_LCOMMON, // large_common_shndx
4578 0, // small_common_section_flags
4579 elfcpp::SHF_X86_64_LARGE, // large_common_section_flags
4580 NULL, // attributes_section
4581 NULL // attributes_vendor
4585 const Target::Target_info Target_x86_64_nacl<32>::x86_64_nacl_info =
4588 false, // is_big_endian
4589 elfcpp::EM_X86_64, // machine_code
4590 false, // has_make_symbol
4591 false, // has_resolve
4592 true, // has_code_fill
4593 true, // is_default_stack_executable
4594 true, // can_icf_inline_merge_sections
4596 "/lib/ld-nacl-x86-64.so.1", // dynamic_linker
4597 0x20000, // default_text_segment_address
4598 0x10000, // abi_pagesize (overridable by -z max-page-size)
4599 0x10000, // common_pagesize (overridable by -z common-page-size)
4600 true, // isolate_execinstr
4601 0x10000000, // rosegment_gap
4602 elfcpp::SHN_UNDEF, // small_common_shndx
4603 elfcpp::SHN_X86_64_LCOMMON, // large_common_shndx
4604 0, // small_common_section_flags
4605 elfcpp::SHF_X86_64_LARGE, // large_common_section_flags
4606 NULL, // attributes_section
4607 NULL // attributes_vendor
4610 #define NACLMASK 0xe0 // 32-byte alignment mask.
4612 // The first entry in the PLT.
4616 Output_data_plt_x86_64_nacl<size>::first_plt_entry[plt_entry_size] =
4618 0xff, 0x35, // pushq contents of memory address
4619 0, 0, 0, 0, // replaced with address of .got + 8
4620 0x4c, 0x8b, 0x1d, // mov GOT+16(%rip), %r11
4621 0, 0, 0, 0, // replaced with address of .got + 16
4622 0x41, 0x83, 0xe3, NACLMASK, // and $-32, %r11d
4623 0x4d, 0x01, 0xfb, // add %r15, %r11
4624 0x41, 0xff, 0xe3, // jmpq *%r11
4626 // 9-byte nop sequence to pad out to the next 32-byte boundary.
4627 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopl %cs:0x0(%rax,%rax,1)
4629 // 32 bytes of nop to pad out to the standard size
4630 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, // excess data32 prefixes
4631 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4632 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, // excess data32 prefixes
4633 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4634 0x66, // excess data32 prefix
4640 Output_data_plt_x86_64_nacl<size>::do_fill_first_plt_entry(
4642 typename elfcpp::Elf_types<size>::Elf_Addr got_address,
4643 typename elfcpp::Elf_types<size>::Elf_Addr plt_address)
4645 memcpy(pov, first_plt_entry, plt_entry_size);
4646 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
4648 - (plt_address + 2 + 4)));
4649 elfcpp::Swap_unaligned<32, false>::writeval(pov + 9,
4651 - (plt_address + 9 + 4)));
4654 // Subsequent entries in the PLT.
4658 Output_data_plt_x86_64_nacl<size>::plt_entry[plt_entry_size] =
4660 0x4c, 0x8b, 0x1d, // mov name@GOTPCREL(%rip),%r11
4661 0, 0, 0, 0, // replaced with address of symbol in .got
4662 0x41, 0x83, 0xe3, NACLMASK, // and $-32, %r11d
4663 0x4d, 0x01, 0xfb, // add %r15, %r11
4664 0x41, 0xff, 0xe3, // jmpq *%r11
4666 // 15-byte nop sequence to pad out to the next 32-byte boundary.
4667 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, // excess data32 prefixes
4668 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4670 // Lazy GOT entries point here (32-byte aligned).
4671 0x68, // pushq immediate
4672 0, 0, 0, 0, // replaced with index into relocation table
4673 0xe9, // jmp relative
4674 0, 0, 0, 0, // replaced with offset to start of .plt0
4676 // 22 bytes of nop to pad out to the standard size.
4677 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, // excess data32 prefixes
4678 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4679 0x0f, 0x1f, 0x80, 0, 0, 0, 0, // nopl 0x0(%rax)
4684 Output_data_plt_x86_64_nacl<size>::do_fill_plt_entry(
4686 typename elfcpp::Elf_types<size>::Elf_Addr got_address,
4687 typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
4688 unsigned int got_offset,
4689 unsigned int plt_offset,
4690 unsigned int plt_index)
4692 memcpy(pov, plt_entry, plt_entry_size);
4693 elfcpp::Swap_unaligned<32, false>::writeval(pov + 3,
4694 (got_address + got_offset
4695 - (plt_address + plt_offset
4698 elfcpp::Swap_unaligned<32, false>::writeval(pov + 33, plt_index);
4699 elfcpp::Swap_unaligned<32, false>::writeval(pov + 38,
4700 - (plt_offset + 38 + 4));
4705 // The reserved TLSDESC entry in the PLT.
4709 Output_data_plt_x86_64_nacl<size>::tlsdesc_plt_entry[plt_entry_size] =
4711 0xff, 0x35, // pushq x(%rip)
4712 0, 0, 0, 0, // replaced with address of linkmap GOT entry (at PLTGOT + 8)
4713 0x4c, 0x8b, 0x1d, // mov y(%rip),%r11
4714 0, 0, 0, 0, // replaced with offset of reserved TLSDESC_GOT entry
4715 0x41, 0x83, 0xe3, NACLMASK, // and $-32, %r11d
4716 0x4d, 0x01, 0xfb, // add %r15, %r11
4717 0x41, 0xff, 0xe3, // jmpq *%r11
4719 // 41 bytes of nop to pad out to the standard size.
4720 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, // excess data32 prefixes
4721 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4722 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, // excess data32 prefixes
4723 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4724 0x66, 0x66, // excess data32 prefixes
4725 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4730 Output_data_plt_x86_64_nacl<size>::do_fill_tlsdesc_entry(
4732 typename elfcpp::Elf_types<size>::Elf_Addr got_address,
4733 typename elfcpp::Elf_types<size>::Elf_Addr plt_address,
4734 typename elfcpp::Elf_types<size>::Elf_Addr got_base,
4735 unsigned int tlsdesc_got_offset,
4736 unsigned int plt_offset)
4738 memcpy(pov, tlsdesc_plt_entry, plt_entry_size);
4739 elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
4741 - (plt_address + plt_offset
4743 elfcpp::Swap_unaligned<32, false>::writeval(pov + 9,
4745 + tlsdesc_got_offset
4746 - (plt_address + plt_offset
4750 // The .eh_frame unwind information for the PLT.
4754 Output_data_plt_x86_64_nacl<size>::plt_eh_frame_fde[plt_eh_frame_fde_size] =
4756 0, 0, 0, 0, // Replaced with offset to .plt.
4757 0, 0, 0, 0, // Replaced with size of .plt.
4758 0, // Augmentation size.
4759 elfcpp::DW_CFA_def_cfa_offset, 16, // DW_CFA_def_cfa_offset: 16.
4760 elfcpp::DW_CFA_advance_loc + 6, // Advance 6 to __PLT__ + 6.
4761 elfcpp::DW_CFA_def_cfa_offset, 24, // DW_CFA_def_cfa_offset: 24.
4762 elfcpp::DW_CFA_advance_loc + 58, // Advance 58 to __PLT__ + 64.
4763 elfcpp::DW_CFA_def_cfa_expression, // DW_CFA_def_cfa_expression.
4764 13, // Block length.
4765 elfcpp::DW_OP_breg7, 8, // Push %rsp + 8.
4766 elfcpp::DW_OP_breg16, 0, // Push %rip.
4767 elfcpp::DW_OP_const1u, 63, // Push 0x3f.
4768 elfcpp::DW_OP_and, // & (%rip & 0x3f).
4769 elfcpp::DW_OP_const1u, 37, // Push 0x25.
4770 elfcpp::DW_OP_ge, // >= ((%rip & 0x3f) >= 0x25)
4771 elfcpp::DW_OP_lit3, // Push 3.
4772 elfcpp::DW_OP_shl, // << (((%rip & 0x3f) >= 0x25) << 3)
4773 elfcpp::DW_OP_plus, // + ((((%rip&0x3f)>=0x25)<<3)+%rsp+8
4774 elfcpp::DW_CFA_nop, // Align to 32 bytes.
4778 // The selector for x86_64-nacl object files.
4781 class Target_selector_x86_64_nacl
4782 : public Target_selector_nacl<Target_selector_x86_64<size>,
4783 Target_x86_64_nacl<size> >
4786 Target_selector_x86_64_nacl()
4787 : Target_selector_nacl<Target_selector_x86_64<size>,
4788 Target_x86_64_nacl<size> >("x86-64",
4790 ? "elf64-x86-64-nacl"
4791 : "elf32-x86-64-nacl",
4794 : "elf32_x86_64_nacl")
4798 Target_selector_x86_64_nacl<64> target_selector_x86_64;
4799 Target_selector_x86_64_nacl<32> target_selector_x32;
4801 } // End anonymous namespace.