1 // x86_64.cc -- x86_64 target support for gold.
3 // Copyright (C) 2006-2015 Free Software Foundation, Inc.
4 // Written by Ian Lance Taylor <iant@google.com>.
6 // This file is part of gold.
8 // This program is free software; you can redistribute it and/or modify
9 // it under the terms of the GNU General Public License as published by
10 // the Free Software Foundation; either version 3 of the License, or
11 // (at your option) any later version.
13 // This program is distributed in the hope that it will be useful,
14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 // GNU General Public License for more details.
18 // You should have received a copy of the GNU General Public License
19 // along with this program; if not, write to the Free Software
20 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
21 // MA 02110-1301, USA.
29 #include "parameters.h"
36 #include "copy-relocs.h"
38 #include "target-reloc.h"
39 #include "target-select.h"
51 // A class to handle the .got.plt section.
53 class Output_data_got_plt_x86_64
: public Output_section_data_build
56 Output_data_got_plt_x86_64(Layout
* layout
)
57 : Output_section_data_build(8),
61 Output_data_got_plt_x86_64(Layout
* layout
, off_t data_size
)
62 : Output_section_data_build(data_size
, 8),
67 // Write out the PLT data.
69 do_write(Output_file
*);
71 // Write to a map file.
73 do_print_to_mapfile(Mapfile
* mapfile
) const
74 { mapfile
->print_output_data(this, "** GOT PLT"); }
77 // A pointer to the Layout class, so that we can find the .dynamic
78 // section when we write out the GOT PLT section.
82 // A class to handle the PLT data.
83 // This is an abstract base class that handles most of the linker details
84 // but does not know the actual contents of PLT entries. The derived
85 // classes below fill in those details.
88 class Output_data_plt_x86_64
: public Output_section_data
91 typedef Output_data_reloc
<elfcpp::SHT_RELA
, true, size
, false> Reloc_section
;
93 Output_data_plt_x86_64(Layout
* layout
, uint64_t addralign
,
94 Output_data_got
<64, false>* got
,
95 Output_data_got_plt_x86_64
* got_plt
,
96 Output_data_space
* got_irelative
)
97 : Output_section_data(addralign
), tlsdesc_rel_(NULL
),
98 irelative_rel_(NULL
), got_(got
), got_plt_(got_plt
),
99 got_irelative_(got_irelative
), count_(0), irelative_count_(0),
100 tlsdesc_got_offset_(-1U), free_list_()
101 { this->init(layout
); }
103 Output_data_plt_x86_64(Layout
* layout
, uint64_t plt_entry_size
,
104 Output_data_got
<64, false>* got
,
105 Output_data_got_plt_x86_64
* got_plt
,
106 Output_data_space
* got_irelative
,
107 unsigned int plt_count
)
108 : Output_section_data((plt_count
+ 1) * plt_entry_size
,
109 plt_entry_size
, false),
110 tlsdesc_rel_(NULL
), irelative_rel_(NULL
), got_(got
),
111 got_plt_(got_plt
), got_irelative_(got_irelative
), count_(plt_count
),
112 irelative_count_(0), tlsdesc_got_offset_(-1U), free_list_()
116 // Initialize the free list and reserve the first entry.
117 this->free_list_
.init((plt_count
+ 1) * plt_entry_size
, false);
118 this->free_list_
.remove(0, plt_entry_size
);
121 // Initialize the PLT section.
123 init(Layout
* layout
);
125 // Add an entry to the PLT.
127 add_entry(Symbol_table
*, Layout
*, Symbol
* gsym
);
129 // Add an entry to the PLT for a local STT_GNU_IFUNC symbol.
131 add_local_ifunc_entry(Symbol_table
* symtab
, Layout
*,
132 Sized_relobj_file
<size
, false>* relobj
,
133 unsigned int local_sym_index
);
135 // Add the relocation for a PLT entry.
137 add_relocation(Symbol_table
*, Layout
*, Symbol
* gsym
,
138 unsigned int got_offset
);
140 // Add the reserved TLSDESC_PLT entry to the PLT.
142 reserve_tlsdesc_entry(unsigned int got_offset
)
143 { this->tlsdesc_got_offset_
= got_offset
; }
145 // Return true if a TLSDESC_PLT entry has been reserved.
147 has_tlsdesc_entry() const
148 { return this->tlsdesc_got_offset_
!= -1U; }
150 // Return the GOT offset for the reserved TLSDESC_PLT entry.
152 get_tlsdesc_got_offset() const
153 { return this->tlsdesc_got_offset_
; }
155 // Return the offset of the reserved TLSDESC_PLT entry.
157 get_tlsdesc_plt_offset() const
159 return ((this->count_
+ this->irelative_count_
+ 1)
160 * this->get_plt_entry_size());
163 // Return the .rela.plt section data.
166 { return this->rel_
; }
168 // Return where the TLSDESC relocations should go.
170 rela_tlsdesc(Layout
*);
172 // Return where the IRELATIVE relocations should go in the PLT
175 rela_irelative(Symbol_table
*, Layout
*);
177 // Return whether we created a section for IRELATIVE relocations.
179 has_irelative_section() const
180 { return this->irelative_rel_
!= NULL
; }
182 // Return the number of PLT entries.
185 { return this->count_
+ this->irelative_count_
; }
187 // Return the offset of the first non-reserved PLT entry.
189 first_plt_entry_offset()
190 { return this->get_plt_entry_size(); }
192 // Return the size of a PLT entry.
194 get_plt_entry_size() const
195 { return this->do_get_plt_entry_size(); }
197 // Reserve a slot in the PLT for an existing symbol in an incremental update.
199 reserve_slot(unsigned int plt_index
)
201 this->free_list_
.remove((plt_index
+ 1) * this->get_plt_entry_size(),
202 (plt_index
+ 2) * this->get_plt_entry_size());
205 // Return the PLT address to use for a global symbol.
207 address_for_global(const Symbol
*);
209 // Return the PLT address to use for a local symbol.
211 address_for_local(const Relobj
*, unsigned int symndx
);
213 // Add .eh_frame information for the PLT.
215 add_eh_frame(Layout
* layout
)
216 { this->do_add_eh_frame(layout
); }
219 // Fill in the first PLT entry.
221 fill_first_plt_entry(unsigned char* pov
,
222 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
223 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
)
224 { this->do_fill_first_plt_entry(pov
, got_address
, plt_address
); }
226 // Fill in a normal PLT entry. Returns the offset into the entry that
227 // should be the initial GOT slot value.
229 fill_plt_entry(unsigned char* pov
,
230 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
231 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
232 unsigned int got_offset
,
233 unsigned int plt_offset
,
234 unsigned int plt_index
)
236 return this->do_fill_plt_entry(pov
, got_address
, plt_address
,
237 got_offset
, plt_offset
, plt_index
);
240 // Fill in the reserved TLSDESC PLT entry.
242 fill_tlsdesc_entry(unsigned char* pov
,
243 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
244 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
245 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_base
,
246 unsigned int tlsdesc_got_offset
,
247 unsigned int plt_offset
)
249 this->do_fill_tlsdesc_entry(pov
, got_address
, plt_address
, got_base
,
250 tlsdesc_got_offset
, plt_offset
);
254 do_get_plt_entry_size() const = 0;
257 do_fill_first_plt_entry(unsigned char* pov
,
258 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_addr
,
259 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_addr
)
263 do_fill_plt_entry(unsigned char* pov
,
264 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
265 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
266 unsigned int got_offset
,
267 unsigned int plt_offset
,
268 unsigned int plt_index
) = 0;
271 do_fill_tlsdesc_entry(unsigned char* pov
,
272 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
273 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
274 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_base
,
275 unsigned int tlsdesc_got_offset
,
276 unsigned int plt_offset
) = 0;
279 do_add_eh_frame(Layout
* layout
) = 0;
282 do_adjust_output_section(Output_section
* os
);
284 // Write to a map file.
286 do_print_to_mapfile(Mapfile
* mapfile
) const
287 { mapfile
->print_output_data(this, _("** PLT")); }
289 // The CIE of the .eh_frame unwind information for the PLT.
290 static const int plt_eh_frame_cie_size
= 16;
291 static const unsigned char plt_eh_frame_cie
[plt_eh_frame_cie_size
];
294 // Set the final size.
296 set_final_data_size();
298 // Write out the PLT data.
300 do_write(Output_file
*);
302 // The reloc section.
304 // The TLSDESC relocs, if necessary. These must follow the regular
306 Reloc_section
* tlsdesc_rel_
;
307 // The IRELATIVE relocs, if necessary. These must follow the
308 // regular PLT relocations and the TLSDESC relocations.
309 Reloc_section
* irelative_rel_
;
311 Output_data_got
<64, false>* got_
;
312 // The .got.plt section.
313 Output_data_got_plt_x86_64
* got_plt_
;
314 // The part of the .got.plt section used for IRELATIVE relocs.
315 Output_data_space
* got_irelative_
;
316 // The number of PLT entries.
318 // Number of PLT entries with R_X86_64_IRELATIVE relocs. These
319 // follow the regular PLT entries.
320 unsigned int irelative_count_
;
321 // Offset of the reserved TLSDESC_GOT entry when needed.
322 unsigned int tlsdesc_got_offset_
;
323 // List of available regions within the section, for incremental
325 Free_list free_list_
;
329 class Output_data_plt_x86_64_standard
: public Output_data_plt_x86_64
<size
>
332 Output_data_plt_x86_64_standard(Layout
* layout
,
333 Output_data_got
<64, false>* got
,
334 Output_data_got_plt_x86_64
* got_plt
,
335 Output_data_space
* got_irelative
)
336 : Output_data_plt_x86_64
<size
>(layout
, plt_entry_size
,
337 got
, got_plt
, got_irelative
)
340 Output_data_plt_x86_64_standard(Layout
* layout
,
341 Output_data_got
<64, false>* got
,
342 Output_data_got_plt_x86_64
* got_plt
,
343 Output_data_space
* got_irelative
,
344 unsigned int plt_count
)
345 : Output_data_plt_x86_64
<size
>(layout
, plt_entry_size
,
346 got
, got_plt
, got_irelative
,
352 do_get_plt_entry_size() const
353 { return plt_entry_size
; }
356 do_add_eh_frame(Layout
* layout
)
358 layout
->add_eh_frame_for_plt(this,
359 this->plt_eh_frame_cie
,
360 this->plt_eh_frame_cie_size
,
362 plt_eh_frame_fde_size
);
366 do_fill_first_plt_entry(unsigned char* pov
,
367 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_addr
,
368 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_addr
);
371 do_fill_plt_entry(unsigned char* pov
,
372 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
373 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
374 unsigned int got_offset
,
375 unsigned int plt_offset
,
376 unsigned int plt_index
);
379 do_fill_tlsdesc_entry(unsigned char* pov
,
380 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
381 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
382 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_base
,
383 unsigned int tlsdesc_got_offset
,
384 unsigned int plt_offset
);
387 // The size of an entry in the PLT.
388 static const int plt_entry_size
= 16;
390 // The first entry in the PLT.
391 // From the AMD64 ABI: "Unlike Intel386 ABI, this ABI uses the same
392 // procedure linkage table for both programs and shared objects."
393 static const unsigned char first_plt_entry
[plt_entry_size
];
395 // Other entries in the PLT for an executable.
396 static const unsigned char plt_entry
[plt_entry_size
];
398 // The reserved TLSDESC entry in the PLT for an executable.
399 static const unsigned char tlsdesc_plt_entry
[plt_entry_size
];
401 // The .eh_frame unwind information for the PLT.
402 static const int plt_eh_frame_fde_size
= 32;
403 static const unsigned char plt_eh_frame_fde
[plt_eh_frame_fde_size
];
406 // The x86_64 target class.
408 // http://www.x86-64.org/documentation/abi.pdf
409 // TLS info comes from
410 // http://people.redhat.com/drepper/tls.pdf
411 // http://www.lsd.ic.unicamp.br/~oliva/writeups/TLS/RFC-TLSDESC-x86.txt
414 class Target_x86_64
: public Sized_target
<size
, false>
417 // In the x86_64 ABI (p 68), it says "The AMD64 ABI architectures
418 // uses only Elf64_Rela relocation entries with explicit addends."
419 typedef Output_data_reloc
<elfcpp::SHT_RELA
, true, size
, false> Reloc_section
;
421 Target_x86_64(const Target::Target_info
* info
= &x86_64_info
)
422 : Sized_target
<size
, false>(info
),
423 got_(NULL
), plt_(NULL
), got_plt_(NULL
), got_irelative_(NULL
),
424 got_tlsdesc_(NULL
), global_offset_table_(NULL
), rela_dyn_(NULL
),
425 rela_irelative_(NULL
), copy_relocs_(elfcpp::R_X86_64_COPY
),
426 got_mod_index_offset_(-1U), tlsdesc_reloc_info_(),
427 tls_base_symbol_defined_(false)
430 // Hook for a new output section.
432 do_new_output_section(Output_section
*) const;
434 // Scan the relocations to look for symbol adjustments.
436 gc_process_relocs(Symbol_table
* symtab
,
438 Sized_relobj_file
<size
, false>* object
,
439 unsigned int data_shndx
,
440 unsigned int sh_type
,
441 const unsigned char* prelocs
,
443 Output_section
* output_section
,
444 bool needs_special_offset_handling
,
445 size_t local_symbol_count
,
446 const unsigned char* plocal_symbols
);
448 // Scan the relocations to look for symbol adjustments.
450 scan_relocs(Symbol_table
* symtab
,
452 Sized_relobj_file
<size
, false>* object
,
453 unsigned int data_shndx
,
454 unsigned int sh_type
,
455 const unsigned char* prelocs
,
457 Output_section
* output_section
,
458 bool needs_special_offset_handling
,
459 size_t local_symbol_count
,
460 const unsigned char* plocal_symbols
);
462 // Finalize the sections.
464 do_finalize_sections(Layout
*, const Input_objects
*, Symbol_table
*);
466 // Return the value to use for a dynamic which requires special
469 do_dynsym_value(const Symbol
*) const;
471 // Relocate a section.
473 relocate_section(const Relocate_info
<size
, false>*,
474 unsigned int sh_type
,
475 const unsigned char* prelocs
,
477 Output_section
* output_section
,
478 bool needs_special_offset_handling
,
480 typename
elfcpp::Elf_types
<size
>::Elf_Addr view_address
,
481 section_size_type view_size
,
482 const Reloc_symbol_changes
*);
484 // Scan the relocs during a relocatable link.
486 scan_relocatable_relocs(Symbol_table
* symtab
,
488 Sized_relobj_file
<size
, false>* object
,
489 unsigned int data_shndx
,
490 unsigned int sh_type
,
491 const unsigned char* prelocs
,
493 Output_section
* output_section
,
494 bool needs_special_offset_handling
,
495 size_t local_symbol_count
,
496 const unsigned char* plocal_symbols
,
497 Relocatable_relocs
*);
499 // Emit relocations for a section.
502 const Relocate_info
<size
, false>*,
503 unsigned int sh_type
,
504 const unsigned char* prelocs
,
506 Output_section
* output_section
,
507 typename
elfcpp::Elf_types
<size
>::Elf_Off offset_in_output_section
,
508 const Relocatable_relocs
*,
510 typename
elfcpp::Elf_types
<size
>::Elf_Addr view_address
,
511 section_size_type view_size
,
512 unsigned char* reloc_view
,
513 section_size_type reloc_view_size
);
515 // Return a string used to fill a code section with nops.
517 do_code_fill(section_size_type length
) const;
519 // Return whether SYM is defined by the ABI.
521 do_is_defined_by_abi(const Symbol
* sym
) const
522 { return strcmp(sym
->name(), "__tls_get_addr") == 0; }
524 // Return the symbol index to use for a target specific relocation.
525 // The only target specific relocation is R_X86_64_TLSDESC for a
526 // local symbol, which is an absolute reloc.
528 do_reloc_symbol_index(void*, unsigned int r_type
) const
530 gold_assert(r_type
== elfcpp::R_X86_64_TLSDESC
);
534 // Return the addend to use for a target specific relocation.
536 do_reloc_addend(void* arg
, unsigned int r_type
, uint64_t addend
) const;
538 // Return the PLT section.
540 do_plt_address_for_global(const Symbol
* gsym
) const
541 { return this->plt_section()->address_for_global(gsym
); }
544 do_plt_address_for_local(const Relobj
* relobj
, unsigned int symndx
) const
545 { return this->plt_section()->address_for_local(relobj
, symndx
); }
547 // This function should be defined in targets that can use relocation
548 // types to determine (implemented in local_reloc_may_be_function_pointer
549 // and global_reloc_may_be_function_pointer)
550 // if a function's pointer is taken. ICF uses this in safe mode to only
551 // fold those functions whose pointer is defintely not taken. For x86_64
552 // pie binaries, safe ICF cannot be done by looking at relocation types.
554 do_can_check_for_function_pointers() const
555 { return !parameters
->options().pie(); }
557 // Return the base for a DW_EH_PE_datarel encoding.
559 do_ehframe_datarel_base() const;
561 // Adjust -fsplit-stack code which calls non-split-stack code.
563 do_calls_non_split(Relobj
* object
, unsigned int shndx
,
564 section_offset_type fnoffset
, section_size_type fnsize
,
565 unsigned char* view
, section_size_type view_size
,
566 std::string
* from
, std::string
* to
) const;
568 // Return the size of the GOT section.
572 gold_assert(this->got_
!= NULL
);
573 return this->got_
->data_size();
576 // Return the number of entries in the GOT.
578 got_entry_count() const
580 if (this->got_
== NULL
)
582 return this->got_size() / 8;
585 // Return the number of entries in the PLT.
587 plt_entry_count() const;
589 // Return the offset of the first non-reserved PLT entry.
591 first_plt_entry_offset() const;
593 // Return the size of each PLT entry.
595 plt_entry_size() const;
597 // Create the GOT section for an incremental update.
598 Output_data_got_base
*
599 init_got_plt_for_update(Symbol_table
* symtab
,
601 unsigned int got_count
,
602 unsigned int plt_count
);
604 // Reserve a GOT entry for a local symbol, and regenerate any
605 // necessary dynamic relocations.
607 reserve_local_got_entry(unsigned int got_index
,
608 Sized_relobj
<size
, false>* obj
,
610 unsigned int got_type
);
612 // Reserve a GOT entry for a global symbol, and regenerate any
613 // necessary dynamic relocations.
615 reserve_global_got_entry(unsigned int got_index
, Symbol
* gsym
,
616 unsigned int got_type
);
618 // Register an existing PLT entry for a global symbol.
620 register_global_plt_entry(Symbol_table
*, Layout
*, unsigned int plt_index
,
623 // Force a COPY relocation for a given symbol.
625 emit_copy_reloc(Symbol_table
*, Symbol
*, Output_section
*, off_t
);
627 // Apply an incremental relocation.
629 apply_relocation(const Relocate_info
<size
, false>* relinfo
,
630 typename
elfcpp::Elf_types
<size
>::Elf_Addr r_offset
,
632 typename
elfcpp::Elf_types
<size
>::Elf_Swxword r_addend
,
635 typename
elfcpp::Elf_types
<size
>::Elf_Addr address
,
636 section_size_type view_size
);
638 // Add a new reloc argument, returning the index in the vector.
640 add_tlsdesc_info(Sized_relobj_file
<size
, false>* object
, unsigned int r_sym
)
642 this->tlsdesc_reloc_info_
.push_back(Tlsdesc_info(object
, r_sym
));
643 return this->tlsdesc_reloc_info_
.size() - 1;
646 Output_data_plt_x86_64
<size
>*
647 make_data_plt(Layout
* layout
,
648 Output_data_got
<64, false>* got
,
649 Output_data_got_plt_x86_64
* got_plt
,
650 Output_data_space
* got_irelative
)
652 return this->do_make_data_plt(layout
, got
, got_plt
, got_irelative
);
655 Output_data_plt_x86_64
<size
>*
656 make_data_plt(Layout
* layout
,
657 Output_data_got
<64, false>* got
,
658 Output_data_got_plt_x86_64
* got_plt
,
659 Output_data_space
* got_irelative
,
660 unsigned int plt_count
)
662 return this->do_make_data_plt(layout
, got
, got_plt
, got_irelative
,
666 virtual Output_data_plt_x86_64
<size
>*
667 do_make_data_plt(Layout
* layout
,
668 Output_data_got
<64, false>* got
,
669 Output_data_got_plt_x86_64
* got_plt
,
670 Output_data_space
* got_irelative
)
672 return new Output_data_plt_x86_64_standard
<size
>(layout
, got
, got_plt
,
676 virtual Output_data_plt_x86_64
<size
>*
677 do_make_data_plt(Layout
* layout
,
678 Output_data_got
<64, false>* got
,
679 Output_data_got_plt_x86_64
* got_plt
,
680 Output_data_space
* got_irelative
,
681 unsigned int plt_count
)
683 return new Output_data_plt_x86_64_standard
<size
>(layout
, got
, got_plt
,
689 // The class which scans relocations.
694 : issued_non_pic_error_(false)
698 get_reference_flags(unsigned int r_type
);
701 local(Symbol_table
* symtab
, Layout
* layout
, 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
, unsigned int r_type
,
706 const elfcpp::Sym
<size
, false>& lsym
,
710 global(Symbol_table
* symtab
, Layout
* layout
, Target_x86_64
* target
,
711 Sized_relobj_file
<size
, false>* object
,
712 unsigned int data_shndx
,
713 Output_section
* output_section
,
714 const elfcpp::Rela
<size
, false>& reloc
, unsigned int r_type
,
718 local_reloc_may_be_function_pointer(Symbol_table
* symtab
, Layout
* layout
,
719 Target_x86_64
* target
,
720 Sized_relobj_file
<size
, false>* object
,
721 unsigned int data_shndx
,
722 Output_section
* output_section
,
723 const elfcpp::Rela
<size
, false>& reloc
,
725 const elfcpp::Sym
<size
, false>& lsym
);
728 global_reloc_may_be_function_pointer(Symbol_table
* symtab
, Layout
* layout
,
729 Target_x86_64
* target
,
730 Sized_relobj_file
<size
, false>* object
,
731 unsigned int data_shndx
,
732 Output_section
* output_section
,
733 const elfcpp::Rela
<size
, false>& reloc
,
739 unsupported_reloc_local(Sized_relobj_file
<size
, false>*,
740 unsigned int r_type
);
743 unsupported_reloc_global(Sized_relobj_file
<size
, false>*,
744 unsigned int r_type
, Symbol
*);
747 check_non_pic(Relobj
*, unsigned int r_type
, Symbol
*);
750 possible_function_pointer_reloc(unsigned int r_type
);
753 reloc_needs_plt_for_ifunc(Sized_relobj_file
<size
, false>*,
754 unsigned int r_type
);
756 // Whether we have issued an error about a non-PIC compilation.
757 bool issued_non_pic_error_
;
760 // The class which implements relocation.
765 : skip_call_tls_get_addr_(false)
770 if (this->skip_call_tls_get_addr_
)
772 // FIXME: This needs to specify the location somehow.
773 gold_error(_("missing expected TLS relocation"));
777 // Do a relocation. Return false if the caller should not issue
778 // any warnings about this relocation.
780 relocate(const Relocate_info
<size
, false>*, Target_x86_64
*,
782 size_t relnum
, const elfcpp::Rela
<size
, false>&,
783 unsigned int r_type
, const Sized_symbol
<size
>*,
784 const Symbol_value
<size
>*,
785 unsigned char*, typename
elfcpp::Elf_types
<size
>::Elf_Addr
,
789 // Do a TLS relocation.
791 relocate_tls(const Relocate_info
<size
, false>*, Target_x86_64
*,
792 size_t relnum
, const elfcpp::Rela
<size
, false>&,
793 unsigned int r_type
, const Sized_symbol
<size
>*,
794 const Symbol_value
<size
>*,
795 unsigned char*, typename
elfcpp::Elf_types
<size
>::Elf_Addr
,
798 // Do a TLS General-Dynamic to Initial-Exec transition.
800 tls_gd_to_ie(const Relocate_info
<size
, false>*, size_t relnum
,
801 Output_segment
* tls_segment
,
802 const elfcpp::Rela
<size
, false>&, unsigned int r_type
,
803 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
805 typename
elfcpp::Elf_types
<size
>::Elf_Addr
,
806 section_size_type view_size
);
808 // Do a TLS General-Dynamic to Local-Exec transition.
810 tls_gd_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 TLSDESC-style General-Dynamic to Initial-Exec transition.
819 tls_desc_gd_to_ie(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 typename
elfcpp::Elf_types
<size
>::Elf_Addr
,
825 section_size_type view_size
);
827 // Do a TLSDESC-style General-Dynamic to Local-Exec transition.
829 tls_desc_gd_to_le(const Relocate_info
<size
, false>*, size_t relnum
,
830 Output_segment
* tls_segment
,
831 const elfcpp::Rela
<size
, false>&, unsigned int r_type
,
832 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
834 section_size_type view_size
);
836 // Do a TLS Local-Dynamic to Local-Exec transition.
838 tls_ld_to_le(const Relocate_info
<size
, false>*, size_t relnum
,
839 Output_segment
* tls_segment
,
840 const elfcpp::Rela
<size
, false>&, unsigned int r_type
,
841 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
843 section_size_type view_size
);
845 // Do a TLS Initial-Exec to Local-Exec transition.
847 tls_ie_to_le(const Relocate_info
<size
, false>*, size_t relnum
,
848 Output_segment
* tls_segment
,
849 const elfcpp::Rela
<size
, false>&, unsigned int r_type
,
850 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
852 section_size_type view_size
);
854 // This is set if we should skip the next reloc, which should be a
855 // PLT32 reloc against ___tls_get_addr.
856 bool skip_call_tls_get_addr_
;
859 // A class which returns the size required for a relocation type,
860 // used while scanning relocs during a relocatable link.
861 class Relocatable_size_for_reloc
865 get_size_for_reloc(unsigned int, Relobj
*);
868 // Check if relocation against this symbol is a candidate for
870 // mov foo@GOTPCREL(%rip), %reg
871 // to lea foo(%rip), %reg.
873 can_convert_mov_to_lea(const Symbol
* gsym
)
875 gold_assert(gsym
!= NULL
);
876 return (gsym
->type() != elfcpp::STT_GNU_IFUNC
877 && !gsym
->is_undefined ()
878 && !gsym
->is_from_dynobj()
879 && !gsym
->is_preemptible()
880 && (!parameters
->options().shared()
881 || (gsym
->visibility() != elfcpp::STV_DEFAULT
882 && gsym
->visibility() != elfcpp::STV_PROTECTED
)
883 || parameters
->options().Bsymbolic())
884 && strcmp(gsym
->name(), "_DYNAMIC") != 0);
887 // Adjust TLS relocation type based on the options and whether this
888 // is a local symbol.
889 static tls::Tls_optimization
890 optimize_tls_reloc(bool is_final
, int r_type
);
892 // Get the GOT section, creating it if necessary.
893 Output_data_got
<64, false>*
894 got_section(Symbol_table
*, Layout
*);
896 // Get the GOT PLT section.
897 Output_data_got_plt_x86_64
*
898 got_plt_section() const
900 gold_assert(this->got_plt_
!= NULL
);
901 return this->got_plt_
;
904 // Get the GOT section for TLSDESC entries.
905 Output_data_got
<64, false>*
906 got_tlsdesc_section() const
908 gold_assert(this->got_tlsdesc_
!= NULL
);
909 return this->got_tlsdesc_
;
912 // Create the PLT section.
914 make_plt_section(Symbol_table
* symtab
, Layout
* layout
);
916 // Create a PLT entry for a global symbol.
918 make_plt_entry(Symbol_table
*, Layout
*, Symbol
*);
920 // Create a PLT entry for a local STT_GNU_IFUNC symbol.
922 make_local_ifunc_plt_entry(Symbol_table
*, Layout
*,
923 Sized_relobj_file
<size
, false>* relobj
,
924 unsigned int local_sym_index
);
926 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
928 define_tls_base_symbol(Symbol_table
*, Layout
*);
930 // Create the reserved PLT and GOT entries for the TLS descriptor resolver.
932 reserve_tlsdesc_entries(Symbol_table
* symtab
, Layout
* layout
);
934 // Create a GOT entry for the TLS module index.
936 got_mod_index_entry(Symbol_table
* symtab
, Layout
* layout
,
937 Sized_relobj_file
<size
, false>* object
);
939 // Get the PLT section.
940 Output_data_plt_x86_64
<size
>*
943 gold_assert(this->plt_
!= NULL
);
947 // Get the dynamic reloc section, creating it if necessary.
949 rela_dyn_section(Layout
*);
951 // Get the section to use for TLSDESC relocations.
953 rela_tlsdesc_section(Layout
*) const;
955 // Get the section to use for IRELATIVE relocations.
957 rela_irelative_section(Layout
*);
959 // Add a potential copy relocation.
961 copy_reloc(Symbol_table
* symtab
, Layout
* layout
,
962 Sized_relobj_file
<size
, false>* object
,
963 unsigned int shndx
, Output_section
* output_section
,
964 Symbol
* sym
, const elfcpp::Rela
<size
, false>& reloc
)
966 this->copy_relocs_
.copy_reloc(symtab
, layout
,
967 symtab
->get_sized_symbol
<size
>(sym
),
968 object
, shndx
, output_section
,
969 reloc
, this->rela_dyn_section(layout
));
972 // Information about this specific target which we pass to the
973 // general Target structure.
974 static const Target::Target_info x86_64_info
;
976 // The types of GOT entries needed for this platform.
977 // These values are exposed to the ABI in an incremental link.
978 // Do not renumber existing values without changing the version
979 // number of the .gnu_incremental_inputs section.
982 GOT_TYPE_STANDARD
= 0, // GOT entry for a regular symbol
983 GOT_TYPE_TLS_OFFSET
= 1, // GOT entry for TLS offset
984 GOT_TYPE_TLS_PAIR
= 2, // GOT entry for TLS module/offset pair
985 GOT_TYPE_TLS_DESC
= 3 // GOT entry for TLS_DESC pair
988 // This type is used as the argument to the target specific
989 // relocation routines. The only target specific reloc is
990 // R_X86_64_TLSDESC against a local symbol.
993 Tlsdesc_info(Sized_relobj_file
<size
, false>* a_object
, unsigned int a_r_sym
)
994 : object(a_object
), r_sym(a_r_sym
)
997 // The object in which the local symbol is defined.
998 Sized_relobj_file
<size
, false>* object
;
999 // The local symbol index in the object.
1004 Output_data_got
<64, false>* got_
;
1006 Output_data_plt_x86_64
<size
>* plt_
;
1007 // The GOT PLT section.
1008 Output_data_got_plt_x86_64
* got_plt_
;
1009 // The GOT section for IRELATIVE relocations.
1010 Output_data_space
* got_irelative_
;
1011 // The GOT section for TLSDESC relocations.
1012 Output_data_got
<64, false>* got_tlsdesc_
;
1013 // The _GLOBAL_OFFSET_TABLE_ symbol.
1014 Symbol
* global_offset_table_
;
1015 // The dynamic reloc section.
1016 Reloc_section
* rela_dyn_
;
1017 // The section to use for IRELATIVE relocs.
1018 Reloc_section
* rela_irelative_
;
1019 // Relocs saved to avoid a COPY reloc.
1020 Copy_relocs
<elfcpp::SHT_RELA
, size
, false> copy_relocs_
;
1021 // Offset of the GOT entry for the TLS module index.
1022 unsigned int got_mod_index_offset_
;
1023 // We handle R_X86_64_TLSDESC against a local symbol as a target
1024 // specific relocation. Here we store the object and local symbol
1025 // index for the relocation.
1026 std::vector
<Tlsdesc_info
> tlsdesc_reloc_info_
;
1027 // True if the _TLS_MODULE_BASE_ symbol has been defined.
1028 bool tls_base_symbol_defined_
;
1032 const Target::Target_info Target_x86_64
<64>::x86_64_info
=
1035 false, // is_big_endian
1036 elfcpp::EM_X86_64
, // machine_code
1037 false, // has_make_symbol
1038 false, // has_resolve
1039 true, // has_code_fill
1040 true, // is_default_stack_executable
1041 true, // can_icf_inline_merge_sections
1043 "/lib/ld64.so.1", // program interpreter
1044 0x400000, // default_text_segment_address
1045 0x1000, // abi_pagesize (overridable by -z max-page-size)
1046 0x1000, // common_pagesize (overridable by -z common-page-size)
1047 false, // isolate_execinstr
1049 elfcpp::SHN_UNDEF
, // small_common_shndx
1050 elfcpp::SHN_X86_64_LCOMMON
, // large_common_shndx
1051 0, // small_common_section_flags
1052 elfcpp::SHF_X86_64_LARGE
, // large_common_section_flags
1053 NULL
, // attributes_section
1054 NULL
, // attributes_vendor
1055 "_start" // entry_symbol_name
1059 const Target::Target_info Target_x86_64
<32>::x86_64_info
=
1062 false, // is_big_endian
1063 elfcpp::EM_X86_64
, // machine_code
1064 false, // has_make_symbol
1065 false, // has_resolve
1066 true, // has_code_fill
1067 true, // is_default_stack_executable
1068 true, // can_icf_inline_merge_sections
1070 "/libx32/ldx32.so.1", // program interpreter
1071 0x400000, // default_text_segment_address
1072 0x1000, // abi_pagesize (overridable by -z max-page-size)
1073 0x1000, // common_pagesize (overridable by -z common-page-size)
1074 false, // isolate_execinstr
1076 elfcpp::SHN_UNDEF
, // small_common_shndx
1077 elfcpp::SHN_X86_64_LCOMMON
, // large_common_shndx
1078 0, // small_common_section_flags
1079 elfcpp::SHF_X86_64_LARGE
, // large_common_section_flags
1080 NULL
, // attributes_section
1081 NULL
, // attributes_vendor
1082 "_start" // entry_symbol_name
1085 // This is called when a new output section is created. This is where
1086 // we handle the SHF_X86_64_LARGE.
1090 Target_x86_64
<size
>::do_new_output_section(Output_section
* os
) const
1092 if ((os
->flags() & elfcpp::SHF_X86_64_LARGE
) != 0)
1093 os
->set_is_large_section();
1096 // Get the GOT section, creating it if necessary.
1099 Output_data_got
<64, false>*
1100 Target_x86_64
<size
>::got_section(Symbol_table
* symtab
, Layout
* layout
)
1102 if (this->got_
== NULL
)
1104 gold_assert(symtab
!= NULL
&& layout
!= NULL
);
1106 // When using -z now, we can treat .got.plt as a relro section.
1107 // Without -z now, it is modified after program startup by lazy
1109 bool is_got_plt_relro
= parameters
->options().now();
1110 Output_section_order got_order
= (is_got_plt_relro
1112 : ORDER_RELRO_LAST
);
1113 Output_section_order got_plt_order
= (is_got_plt_relro
1115 : ORDER_NON_RELRO_FIRST
);
1117 this->got_
= new Output_data_got
<64, false>();
1119 layout
->add_output_section_data(".got", elfcpp::SHT_PROGBITS
,
1121 | elfcpp::SHF_WRITE
),
1122 this->got_
, got_order
, true);
1124 this->got_plt_
= new Output_data_got_plt_x86_64(layout
);
1125 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
1127 | elfcpp::SHF_WRITE
),
1128 this->got_plt_
, got_plt_order
,
1131 // The first three entries are reserved.
1132 this->got_plt_
->set_current_data_size(3 * 8);
1134 if (!is_got_plt_relro
)
1136 // Those bytes can go into the relro segment.
1137 layout
->increase_relro(3 * 8);
1140 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
1141 this->global_offset_table_
=
1142 symtab
->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL
,
1143 Symbol_table::PREDEFINED
,
1145 0, 0, elfcpp::STT_OBJECT
,
1147 elfcpp::STV_HIDDEN
, 0,
1150 // If there are any IRELATIVE relocations, they get GOT entries
1151 // in .got.plt after the jump slot entries.
1152 this->got_irelative_
= new Output_data_space(8, "** GOT IRELATIVE PLT");
1153 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
1155 | elfcpp::SHF_WRITE
),
1156 this->got_irelative_
,
1157 got_plt_order
, is_got_plt_relro
);
1159 // If there are any TLSDESC relocations, they get GOT entries in
1160 // .got.plt after the jump slot and IRELATIVE entries.
1161 this->got_tlsdesc_
= new Output_data_got
<64, false>();
1162 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
1164 | elfcpp::SHF_WRITE
),
1166 got_plt_order
, is_got_plt_relro
);
1172 // Get the dynamic reloc section, creating it if necessary.
1175 typename Target_x86_64
<size
>::Reloc_section
*
1176 Target_x86_64
<size
>::rela_dyn_section(Layout
* layout
)
1178 if (this->rela_dyn_
== NULL
)
1180 gold_assert(layout
!= NULL
);
1181 this->rela_dyn_
= new Reloc_section(parameters
->options().combreloc());
1182 layout
->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA
,
1183 elfcpp::SHF_ALLOC
, this->rela_dyn_
,
1184 ORDER_DYNAMIC_RELOCS
, false);
1186 return this->rela_dyn_
;
1189 // Get the section to use for IRELATIVE relocs, creating it if
1190 // necessary. These go in .rela.dyn, but only after all other dynamic
1191 // relocations. They need to follow the other dynamic relocations so
1192 // that they can refer to global variables initialized by those
1196 typename Target_x86_64
<size
>::Reloc_section
*
1197 Target_x86_64
<size
>::rela_irelative_section(Layout
* layout
)
1199 if (this->rela_irelative_
== NULL
)
1201 // Make sure we have already created the dynamic reloc section.
1202 this->rela_dyn_section(layout
);
1203 this->rela_irelative_
= new Reloc_section(false);
1204 layout
->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA
,
1205 elfcpp::SHF_ALLOC
, this->rela_irelative_
,
1206 ORDER_DYNAMIC_RELOCS
, false);
1207 gold_assert(this->rela_dyn_
->output_section()
1208 == this->rela_irelative_
->output_section());
1210 return this->rela_irelative_
;
1213 // Write the first three reserved words of the .got.plt section.
1214 // The remainder of the section is written while writing the PLT
1215 // in Output_data_plt_i386::do_write.
1218 Output_data_got_plt_x86_64::do_write(Output_file
* of
)
1220 // The first entry in the GOT is the address of the .dynamic section
1221 // aka the PT_DYNAMIC segment. The next two entries are reserved.
1222 // We saved space for them when we created the section in
1223 // Target_x86_64::got_section.
1224 const off_t got_file_offset
= this->offset();
1225 gold_assert(this->data_size() >= 24);
1226 unsigned char* const got_view
= of
->get_output_view(got_file_offset
, 24);
1227 Output_section
* dynamic
= this->layout_
->dynamic_section();
1228 uint64_t dynamic_addr
= dynamic
== NULL
? 0 : dynamic
->address();
1229 elfcpp::Swap
<64, false>::writeval(got_view
, dynamic_addr
);
1230 memset(got_view
+ 8, 0, 16);
1231 of
->write_output_view(got_file_offset
, 24, got_view
);
1234 // Initialize the PLT section.
1238 Output_data_plt_x86_64
<size
>::init(Layout
* layout
)
1240 this->rel_
= new Reloc_section(false);
1241 layout
->add_output_section_data(".rela.plt", elfcpp::SHT_RELA
,
1242 elfcpp::SHF_ALLOC
, this->rel_
,
1243 ORDER_DYNAMIC_PLT_RELOCS
, false);
1248 Output_data_plt_x86_64
<size
>::do_adjust_output_section(Output_section
* os
)
1250 os
->set_entsize(this->get_plt_entry_size());
1253 // Add an entry to the PLT.
1257 Output_data_plt_x86_64
<size
>::add_entry(Symbol_table
* symtab
, Layout
* layout
,
1260 gold_assert(!gsym
->has_plt_offset());
1262 unsigned int plt_index
;
1264 section_offset_type got_offset
;
1266 unsigned int* pcount
;
1267 unsigned int offset
;
1268 unsigned int reserved
;
1269 Output_section_data_build
* got
;
1270 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
1271 && gsym
->can_use_relative_reloc(false))
1273 pcount
= &this->irelative_count_
;
1276 got
= this->got_irelative_
;
1280 pcount
= &this->count_
;
1283 got
= this->got_plt_
;
1286 if (!this->is_data_size_valid())
1288 // Note that when setting the PLT offset for a non-IRELATIVE
1289 // entry we skip the initial reserved PLT entry.
1290 plt_index
= *pcount
+ offset
;
1291 plt_offset
= plt_index
* this->get_plt_entry_size();
1295 got_offset
= (plt_index
- offset
+ reserved
) * 8;
1296 gold_assert(got_offset
== got
->current_data_size());
1298 // Every PLT entry needs a GOT entry which points back to the PLT
1299 // entry (this will be changed by the dynamic linker, normally
1300 // lazily when the function is called).
1301 got
->set_current_data_size(got_offset
+ 8);
1305 // FIXME: This is probably not correct for IRELATIVE relocs.
1307 // For incremental updates, find an available slot.
1308 plt_offset
= this->free_list_
.allocate(this->get_plt_entry_size(),
1309 this->get_plt_entry_size(), 0);
1310 if (plt_offset
== -1)
1311 gold_fallback(_("out of patch space (PLT);"
1312 " relink with --incremental-full"));
1314 // The GOT and PLT entries have a 1-1 correspondance, so the GOT offset
1315 // can be calculated from the PLT index, adjusting for the three
1316 // reserved entries at the beginning of the GOT.
1317 plt_index
= plt_offset
/ this->get_plt_entry_size() - 1;
1318 got_offset
= (plt_index
- offset
+ reserved
) * 8;
1321 gsym
->set_plt_offset(plt_offset
);
1323 // Every PLT entry needs a reloc.
1324 this->add_relocation(symtab
, layout
, gsym
, got_offset
);
1326 // Note that we don't need to save the symbol. The contents of the
1327 // PLT are independent of which symbols are used. The symbols only
1328 // appear in the relocations.
1331 // Add an entry to the PLT for a local STT_GNU_IFUNC symbol. Return
1336 Output_data_plt_x86_64
<size
>::add_local_ifunc_entry(
1337 Symbol_table
* symtab
,
1339 Sized_relobj_file
<size
, false>* relobj
,
1340 unsigned int local_sym_index
)
1342 unsigned int plt_offset
= this->irelative_count_
* this->get_plt_entry_size();
1343 ++this->irelative_count_
;
1345 section_offset_type got_offset
= this->got_irelative_
->current_data_size();
1347 // Every PLT entry needs a GOT entry which points back to the PLT
1349 this->got_irelative_
->set_current_data_size(got_offset
+ 8);
1351 // Every PLT entry needs a reloc.
1352 Reloc_section
* rela
= this->rela_irelative(symtab
, layout
);
1353 rela
->add_symbolless_local_addend(relobj
, local_sym_index
,
1354 elfcpp::R_X86_64_IRELATIVE
,
1355 this->got_irelative_
, got_offset
, 0);
1360 // Add the relocation for a PLT entry.
1364 Output_data_plt_x86_64
<size
>::add_relocation(Symbol_table
* symtab
,
1367 unsigned int got_offset
)
1369 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
1370 && gsym
->can_use_relative_reloc(false))
1372 Reloc_section
* rela
= this->rela_irelative(symtab
, layout
);
1373 rela
->add_symbolless_global_addend(gsym
, elfcpp::R_X86_64_IRELATIVE
,
1374 this->got_irelative_
, got_offset
, 0);
1378 gsym
->set_needs_dynsym_entry();
1379 this->rel_
->add_global(gsym
, elfcpp::R_X86_64_JUMP_SLOT
, this->got_plt_
,
1384 // Return where the TLSDESC relocations should go, creating it if
1385 // necessary. These follow the JUMP_SLOT relocations.
1388 typename Output_data_plt_x86_64
<size
>::Reloc_section
*
1389 Output_data_plt_x86_64
<size
>::rela_tlsdesc(Layout
* layout
)
1391 if (this->tlsdesc_rel_
== NULL
)
1393 this->tlsdesc_rel_
= new Reloc_section(false);
1394 layout
->add_output_section_data(".rela.plt", elfcpp::SHT_RELA
,
1395 elfcpp::SHF_ALLOC
, this->tlsdesc_rel_
,
1396 ORDER_DYNAMIC_PLT_RELOCS
, false);
1397 gold_assert(this->tlsdesc_rel_
->output_section()
1398 == this->rel_
->output_section());
1400 return this->tlsdesc_rel_
;
1403 // Return where the IRELATIVE relocations should go in the PLT. These
1404 // follow the JUMP_SLOT and the TLSDESC relocations.
1407 typename Output_data_plt_x86_64
<size
>::Reloc_section
*
1408 Output_data_plt_x86_64
<size
>::rela_irelative(Symbol_table
* symtab
,
1411 if (this->irelative_rel_
== NULL
)
1413 // Make sure we have a place for the TLSDESC relocations, in
1414 // case we see any later on.
1415 this->rela_tlsdesc(layout
);
1416 this->irelative_rel_
= new Reloc_section(false);
1417 layout
->add_output_section_data(".rela.plt", elfcpp::SHT_RELA
,
1418 elfcpp::SHF_ALLOC
, this->irelative_rel_
,
1419 ORDER_DYNAMIC_PLT_RELOCS
, false);
1420 gold_assert(this->irelative_rel_
->output_section()
1421 == this->rel_
->output_section());
1423 if (parameters
->doing_static_link())
1425 // A statically linked executable will only have a .rela.plt
1426 // section to hold R_X86_64_IRELATIVE relocs for
1427 // STT_GNU_IFUNC symbols. The library will use these
1428 // symbols to locate the IRELATIVE relocs at program startup
1430 symtab
->define_in_output_data("__rela_iplt_start", NULL
,
1431 Symbol_table::PREDEFINED
,
1432 this->irelative_rel_
, 0, 0,
1433 elfcpp::STT_NOTYPE
, elfcpp::STB_GLOBAL
,
1434 elfcpp::STV_HIDDEN
, 0, false, true);
1435 symtab
->define_in_output_data("__rela_iplt_end", NULL
,
1436 Symbol_table::PREDEFINED
,
1437 this->irelative_rel_
, 0, 0,
1438 elfcpp::STT_NOTYPE
, elfcpp::STB_GLOBAL
,
1439 elfcpp::STV_HIDDEN
, 0, true, true);
1442 return this->irelative_rel_
;
1445 // Return the PLT address to use for a global symbol.
1449 Output_data_plt_x86_64
<size
>::address_for_global(const Symbol
* gsym
)
1451 uint64_t offset
= 0;
1452 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
1453 && gsym
->can_use_relative_reloc(false))
1454 offset
= (this->count_
+ 1) * this->get_plt_entry_size();
1455 return this->address() + offset
+ gsym
->plt_offset();
1458 // Return the PLT address to use for a local symbol. These are always
1459 // IRELATIVE relocs.
1463 Output_data_plt_x86_64
<size
>::address_for_local(const Relobj
* object
,
1466 return (this->address()
1467 + (this->count_
+ 1) * this->get_plt_entry_size()
1468 + object
->local_plt_offset(r_sym
));
1471 // Set the final size.
1474 Output_data_plt_x86_64
<size
>::set_final_data_size()
1476 unsigned int count
= this->count_
+ this->irelative_count_
;
1477 if (this->has_tlsdesc_entry())
1479 this->set_data_size((count
+ 1) * this->get_plt_entry_size());
1482 // The first entry in the PLT for an executable.
1486 Output_data_plt_x86_64_standard
<size
>::first_plt_entry
[plt_entry_size
] =
1488 // From AMD64 ABI Draft 0.98, page 76
1489 0xff, 0x35, // pushq contents of memory address
1490 0, 0, 0, 0, // replaced with address of .got + 8
1491 0xff, 0x25, // jmp indirect
1492 0, 0, 0, 0, // replaced with address of .got + 16
1493 0x90, 0x90, 0x90, 0x90 // noop (x4)
1498 Output_data_plt_x86_64_standard
<size
>::do_fill_first_plt_entry(
1500 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
1501 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
)
1503 memcpy(pov
, first_plt_entry
, plt_entry_size
);
1504 // We do a jmp relative to the PC at the end of this instruction.
1505 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
1507 - (plt_address
+ 6)));
1508 elfcpp::Swap
<32, false>::writeval(pov
+ 8,
1510 - (plt_address
+ 12)));
1513 // Subsequent entries in the PLT for an executable.
1517 Output_data_plt_x86_64_standard
<size
>::plt_entry
[plt_entry_size
] =
1519 // From AMD64 ABI Draft 0.98, page 76
1520 0xff, 0x25, // jmpq indirect
1521 0, 0, 0, 0, // replaced with address of symbol in .got
1522 0x68, // pushq immediate
1523 0, 0, 0, 0, // replaced with offset into relocation table
1524 0xe9, // jmpq relative
1525 0, 0, 0, 0 // replaced with offset to start of .plt
1530 Output_data_plt_x86_64_standard
<size
>::do_fill_plt_entry(
1532 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
1533 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
1534 unsigned int got_offset
,
1535 unsigned int plt_offset
,
1536 unsigned int plt_index
)
1538 // Check PC-relative offset overflow in PLT entry.
1539 uint64_t plt_got_pcrel_offset
= (got_address
+ got_offset
1540 - (plt_address
+ plt_offset
+ 6));
1541 if (Bits
<32>::has_overflow(plt_got_pcrel_offset
))
1542 gold_error(_("PC-relative offset overflow in PLT entry %d"),
1545 memcpy(pov
, plt_entry
, plt_entry_size
);
1546 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
1547 plt_got_pcrel_offset
);
1549 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 7, plt_index
);
1550 elfcpp::Swap
<32, false>::writeval(pov
+ 12,
1551 - (plt_offset
+ plt_entry_size
));
1556 // The reserved TLSDESC entry in the PLT for an executable.
1560 Output_data_plt_x86_64_standard
<size
>::tlsdesc_plt_entry
[plt_entry_size
] =
1562 // From Alexandre Oliva, "Thread-Local Storage Descriptors for IA32
1563 // and AMD64/EM64T", Version 0.9.4 (2005-10-10).
1564 0xff, 0x35, // pushq x(%rip)
1565 0, 0, 0, 0, // replaced with address of linkmap GOT entry (at PLTGOT + 8)
1566 0xff, 0x25, // jmpq *y(%rip)
1567 0, 0, 0, 0, // replaced with offset of reserved TLSDESC_GOT entry
1574 Output_data_plt_x86_64_standard
<size
>::do_fill_tlsdesc_entry(
1576 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
1577 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
1578 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_base
,
1579 unsigned int tlsdesc_got_offset
,
1580 unsigned int plt_offset
)
1582 memcpy(pov
, tlsdesc_plt_entry
, plt_entry_size
);
1583 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
1585 - (plt_address
+ plt_offset
1587 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 8,
1589 + tlsdesc_got_offset
1590 - (plt_address
+ plt_offset
1594 // The .eh_frame unwind information for the PLT.
1598 Output_data_plt_x86_64
<size
>::plt_eh_frame_cie
[plt_eh_frame_cie_size
] =
1601 'z', // Augmentation: augmentation size included.
1602 'R', // Augmentation: FDE encoding included.
1603 '\0', // End of augmentation string.
1604 1, // Code alignment factor.
1605 0x78, // Data alignment factor.
1606 16, // Return address column.
1607 1, // Augmentation size.
1608 (elfcpp::DW_EH_PE_pcrel
// FDE encoding.
1609 | elfcpp::DW_EH_PE_sdata4
),
1610 elfcpp::DW_CFA_def_cfa
, 7, 8, // DW_CFA_def_cfa: r7 (rsp) ofs 8.
1611 elfcpp::DW_CFA_offset
+ 16, 1,// DW_CFA_offset: r16 (rip) at cfa-8.
1612 elfcpp::DW_CFA_nop
, // Align to 16 bytes.
1618 Output_data_plt_x86_64_standard
<size
>::plt_eh_frame_fde
[plt_eh_frame_fde_size
] =
1620 0, 0, 0, 0, // Replaced with offset to .plt.
1621 0, 0, 0, 0, // Replaced with size of .plt.
1622 0, // Augmentation size.
1623 elfcpp::DW_CFA_def_cfa_offset
, 16, // DW_CFA_def_cfa_offset: 16.
1624 elfcpp::DW_CFA_advance_loc
+ 6, // Advance 6 to __PLT__ + 6.
1625 elfcpp::DW_CFA_def_cfa_offset
, 24, // DW_CFA_def_cfa_offset: 24.
1626 elfcpp::DW_CFA_advance_loc
+ 10, // Advance 10 to __PLT__ + 16.
1627 elfcpp::DW_CFA_def_cfa_expression
, // DW_CFA_def_cfa_expression.
1628 11, // Block length.
1629 elfcpp::DW_OP_breg7
, 8, // Push %rsp + 8.
1630 elfcpp::DW_OP_breg16
, 0, // Push %rip.
1631 elfcpp::DW_OP_lit15
, // Push 0xf.
1632 elfcpp::DW_OP_and
, // & (%rip & 0xf).
1633 elfcpp::DW_OP_lit11
, // Push 0xb.
1634 elfcpp::DW_OP_ge
, // >= ((%rip & 0xf) >= 0xb)
1635 elfcpp::DW_OP_lit3
, // Push 3.
1636 elfcpp::DW_OP_shl
, // << (((%rip & 0xf) >= 0xb) << 3)
1637 elfcpp::DW_OP_plus
, // + ((((%rip&0xf)>=0xb)<<3)+%rsp+8
1638 elfcpp::DW_CFA_nop
, // Align to 32 bytes.
1644 // Write out the PLT. This uses the hand-coded instructions above,
1645 // and adjusts them as needed. This is specified by the AMD64 ABI.
1649 Output_data_plt_x86_64
<size
>::do_write(Output_file
* of
)
1651 const off_t offset
= this->offset();
1652 const section_size_type oview_size
=
1653 convert_to_section_size_type(this->data_size());
1654 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
1656 const off_t got_file_offset
= this->got_plt_
->offset();
1657 gold_assert(parameters
->incremental_update()
1658 || (got_file_offset
+ this->got_plt_
->data_size()
1659 == this->got_irelative_
->offset()));
1660 const section_size_type got_size
=
1661 convert_to_section_size_type(this->got_plt_
->data_size()
1662 + this->got_irelative_
->data_size());
1663 unsigned char* const got_view
= of
->get_output_view(got_file_offset
,
1666 unsigned char* pov
= oview
;
1668 // The base address of the .plt section.
1669 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
= this->address();
1670 // The base address of the .got section.
1671 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_base
= this->got_
->address();
1672 // The base address of the PLT portion of the .got section,
1673 // which is where the GOT pointer will point, and where the
1674 // three reserved GOT entries are located.
1675 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
1676 = this->got_plt_
->address();
1678 this->fill_first_plt_entry(pov
, got_address
, plt_address
);
1679 pov
+= this->get_plt_entry_size();
1681 // The first three entries in the GOT are reserved, and are written
1682 // by Output_data_got_plt_x86_64::do_write.
1683 unsigned char* got_pov
= got_view
+ 24;
1685 unsigned int plt_offset
= this->get_plt_entry_size();
1686 unsigned int got_offset
= 24;
1687 const unsigned int count
= this->count_
+ this->irelative_count_
;
1688 for (unsigned int plt_index
= 0;
1691 pov
+= this->get_plt_entry_size(),
1693 plt_offset
+= this->get_plt_entry_size(),
1696 // Set and adjust the PLT entry itself.
1697 unsigned int lazy_offset
= this->fill_plt_entry(pov
,
1698 got_address
, plt_address
,
1699 got_offset
, plt_offset
,
1702 // Set the entry in the GOT.
1703 elfcpp::Swap
<64, false>::writeval(got_pov
,
1704 plt_address
+ plt_offset
+ lazy_offset
);
1707 if (this->has_tlsdesc_entry())
1709 // Set and adjust the reserved TLSDESC PLT entry.
1710 unsigned int tlsdesc_got_offset
= this->get_tlsdesc_got_offset();
1711 this->fill_tlsdesc_entry(pov
, got_address
, plt_address
, got_base
,
1712 tlsdesc_got_offset
, plt_offset
);
1713 pov
+= this->get_plt_entry_size();
1716 gold_assert(static_cast<section_size_type
>(pov
- oview
) == oview_size
);
1717 gold_assert(static_cast<section_size_type
>(got_pov
- got_view
) == got_size
);
1719 of
->write_output_view(offset
, oview_size
, oview
);
1720 of
->write_output_view(got_file_offset
, got_size
, got_view
);
1723 // Create the PLT section.
1727 Target_x86_64
<size
>::make_plt_section(Symbol_table
* symtab
, Layout
* layout
)
1729 if (this->plt_
== NULL
)
1731 // Create the GOT sections first.
1732 this->got_section(symtab
, layout
);
1734 this->plt_
= this->make_data_plt(layout
, this->got_
, this->got_plt_
,
1735 this->got_irelative_
);
1737 // Add unwind information if requested.
1738 if (parameters
->options().ld_generated_unwind_info())
1739 this->plt_
->add_eh_frame(layout
);
1741 layout
->add_output_section_data(".plt", elfcpp::SHT_PROGBITS
,
1743 | elfcpp::SHF_EXECINSTR
),
1744 this->plt_
, ORDER_PLT
, false);
1746 // Make the sh_info field of .rela.plt point to .plt.
1747 Output_section
* rela_plt_os
= this->plt_
->rela_plt()->output_section();
1748 rela_plt_os
->set_info_section(this->plt_
->output_section());
1752 // Return the section for TLSDESC relocations.
1755 typename Target_x86_64
<size
>::Reloc_section
*
1756 Target_x86_64
<size
>::rela_tlsdesc_section(Layout
* layout
) const
1758 return this->plt_section()->rela_tlsdesc(layout
);
1761 // Create a PLT entry for a global symbol.
1765 Target_x86_64
<size
>::make_plt_entry(Symbol_table
* symtab
, Layout
* layout
,
1768 if (gsym
->has_plt_offset())
1771 if (this->plt_
== NULL
)
1772 this->make_plt_section(symtab
, layout
);
1774 this->plt_
->add_entry(symtab
, layout
, gsym
);
1777 // Make a PLT entry for a local STT_GNU_IFUNC symbol.
1781 Target_x86_64
<size
>::make_local_ifunc_plt_entry(
1782 Symbol_table
* symtab
, Layout
* layout
,
1783 Sized_relobj_file
<size
, false>* relobj
,
1784 unsigned int local_sym_index
)
1786 if (relobj
->local_has_plt_offset(local_sym_index
))
1788 if (this->plt_
== NULL
)
1789 this->make_plt_section(symtab
, layout
);
1790 unsigned int plt_offset
= this->plt_
->add_local_ifunc_entry(symtab
, layout
,
1793 relobj
->set_local_plt_offset(local_sym_index
, plt_offset
);
1796 // Return the number of entries in the PLT.
1800 Target_x86_64
<size
>::plt_entry_count() const
1802 if (this->plt_
== NULL
)
1804 return this->plt_
->entry_count();
1807 // Return the offset of the first non-reserved PLT entry.
1811 Target_x86_64
<size
>::first_plt_entry_offset() const
1813 return this->plt_
->first_plt_entry_offset();
1816 // Return the size of each PLT entry.
1820 Target_x86_64
<size
>::plt_entry_size() const
1822 return this->plt_
->get_plt_entry_size();
1825 // Create the GOT and PLT sections for an incremental update.
1828 Output_data_got_base
*
1829 Target_x86_64
<size
>::init_got_plt_for_update(Symbol_table
* symtab
,
1831 unsigned int got_count
,
1832 unsigned int plt_count
)
1834 gold_assert(this->got_
== NULL
);
1836 this->got_
= new Output_data_got
<64, false>(got_count
* 8);
1837 layout
->add_output_section_data(".got", elfcpp::SHT_PROGBITS
,
1839 | elfcpp::SHF_WRITE
),
1840 this->got_
, ORDER_RELRO_LAST
,
1843 // Add the three reserved entries.
1844 this->got_plt_
= new Output_data_got_plt_x86_64(layout
, (plt_count
+ 3) * 8);
1845 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
1847 | elfcpp::SHF_WRITE
),
1848 this->got_plt_
, ORDER_NON_RELRO_FIRST
,
1851 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
1852 this->global_offset_table_
=
1853 symtab
->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL
,
1854 Symbol_table::PREDEFINED
,
1856 0, 0, elfcpp::STT_OBJECT
,
1858 elfcpp::STV_HIDDEN
, 0,
1861 // If there are any TLSDESC relocations, they get GOT entries in
1862 // .got.plt after the jump slot entries.
1863 // FIXME: Get the count for TLSDESC entries.
1864 this->got_tlsdesc_
= new Output_data_got
<64, false>(0);
1865 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
1866 elfcpp::SHF_ALLOC
| elfcpp::SHF_WRITE
,
1868 ORDER_NON_RELRO_FIRST
, false);
1870 // If there are any IRELATIVE relocations, they get GOT entries in
1871 // .got.plt after the jump slot and TLSDESC entries.
1872 this->got_irelative_
= new Output_data_space(0, 8, "** GOT IRELATIVE PLT");
1873 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
1874 elfcpp::SHF_ALLOC
| elfcpp::SHF_WRITE
,
1875 this->got_irelative_
,
1876 ORDER_NON_RELRO_FIRST
, false);
1878 // Create the PLT section.
1879 this->plt_
= this->make_data_plt(layout
, this->got_
,
1881 this->got_irelative_
,
1884 // Add unwind information if requested.
1885 if (parameters
->options().ld_generated_unwind_info())
1886 this->plt_
->add_eh_frame(layout
);
1888 layout
->add_output_section_data(".plt", elfcpp::SHT_PROGBITS
,
1889 elfcpp::SHF_ALLOC
| elfcpp::SHF_EXECINSTR
,
1890 this->plt_
, ORDER_PLT
, false);
1892 // Make the sh_info field of .rela.plt point to .plt.
1893 Output_section
* rela_plt_os
= this->plt_
->rela_plt()->output_section();
1894 rela_plt_os
->set_info_section(this->plt_
->output_section());
1896 // Create the rela_dyn section.
1897 this->rela_dyn_section(layout
);
1902 // Reserve a GOT entry for a local symbol, and regenerate any
1903 // necessary dynamic relocations.
1907 Target_x86_64
<size
>::reserve_local_got_entry(
1908 unsigned int got_index
,
1909 Sized_relobj
<size
, false>* obj
,
1911 unsigned int got_type
)
1913 unsigned int got_offset
= got_index
* 8;
1914 Reloc_section
* rela_dyn
= this->rela_dyn_section(NULL
);
1916 this->got_
->reserve_local(got_index
, obj
, r_sym
, got_type
);
1919 case GOT_TYPE_STANDARD
:
1920 if (parameters
->options().output_is_position_independent())
1921 rela_dyn
->add_local_relative(obj
, r_sym
, elfcpp::R_X86_64_RELATIVE
,
1922 this->got_
, got_offset
, 0, false);
1924 case GOT_TYPE_TLS_OFFSET
:
1925 rela_dyn
->add_local(obj
, r_sym
, elfcpp::R_X86_64_TPOFF64
,
1926 this->got_
, got_offset
, 0);
1928 case GOT_TYPE_TLS_PAIR
:
1929 this->got_
->reserve_slot(got_index
+ 1);
1930 rela_dyn
->add_local(obj
, r_sym
, elfcpp::R_X86_64_DTPMOD64
,
1931 this->got_
, got_offset
, 0);
1933 case GOT_TYPE_TLS_DESC
:
1934 gold_fatal(_("TLS_DESC not yet supported for incremental linking"));
1935 // this->got_->reserve_slot(got_index + 1);
1936 // rela_dyn->add_target_specific(elfcpp::R_X86_64_TLSDESC, arg,
1937 // this->got_, got_offset, 0);
1944 // Reserve a GOT entry for a global symbol, and regenerate any
1945 // necessary dynamic relocations.
1949 Target_x86_64
<size
>::reserve_global_got_entry(unsigned int got_index
,
1951 unsigned int got_type
)
1953 unsigned int got_offset
= got_index
* 8;
1954 Reloc_section
* rela_dyn
= this->rela_dyn_section(NULL
);
1956 this->got_
->reserve_global(got_index
, gsym
, got_type
);
1959 case GOT_TYPE_STANDARD
:
1960 if (!gsym
->final_value_is_known())
1962 if (gsym
->is_from_dynobj()
1963 || gsym
->is_undefined()
1964 || gsym
->is_preemptible()
1965 || gsym
->type() == elfcpp::STT_GNU_IFUNC
)
1966 rela_dyn
->add_global(gsym
, elfcpp::R_X86_64_GLOB_DAT
,
1967 this->got_
, got_offset
, 0);
1969 rela_dyn
->add_global_relative(gsym
, elfcpp::R_X86_64_RELATIVE
,
1970 this->got_
, got_offset
, 0, false);
1973 case GOT_TYPE_TLS_OFFSET
:
1974 rela_dyn
->add_global_relative(gsym
, elfcpp::R_X86_64_TPOFF64
,
1975 this->got_
, got_offset
, 0, false);
1977 case GOT_TYPE_TLS_PAIR
:
1978 this->got_
->reserve_slot(got_index
+ 1);
1979 rela_dyn
->add_global_relative(gsym
, elfcpp::R_X86_64_DTPMOD64
,
1980 this->got_
, got_offset
, 0, false);
1981 rela_dyn
->add_global_relative(gsym
, elfcpp::R_X86_64_DTPOFF64
,
1982 this->got_
, got_offset
+ 8, 0, false);
1984 case GOT_TYPE_TLS_DESC
:
1985 this->got_
->reserve_slot(got_index
+ 1);
1986 rela_dyn
->add_global_relative(gsym
, elfcpp::R_X86_64_TLSDESC
,
1987 this->got_
, got_offset
, 0, false);
1994 // Register an existing PLT entry for a global symbol.
1998 Target_x86_64
<size
>::register_global_plt_entry(Symbol_table
* symtab
,
2000 unsigned int plt_index
,
2003 gold_assert(this->plt_
!= NULL
);
2004 gold_assert(!gsym
->has_plt_offset());
2006 this->plt_
->reserve_slot(plt_index
);
2008 gsym
->set_plt_offset((plt_index
+ 1) * this->plt_entry_size());
2010 unsigned int got_offset
= (plt_index
+ 3) * 8;
2011 this->plt_
->add_relocation(symtab
, layout
, gsym
, got_offset
);
2014 // Force a COPY relocation for a given symbol.
2018 Target_x86_64
<size
>::emit_copy_reloc(
2019 Symbol_table
* symtab
, Symbol
* sym
, Output_section
* os
, off_t offset
)
2021 this->copy_relocs_
.emit_copy_reloc(symtab
,
2022 symtab
->get_sized_symbol
<size
>(sym
),
2025 this->rela_dyn_section(NULL
));
2028 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
2032 Target_x86_64
<size
>::define_tls_base_symbol(Symbol_table
* symtab
,
2035 if (this->tls_base_symbol_defined_
)
2038 Output_segment
* tls_segment
= layout
->tls_segment();
2039 if (tls_segment
!= NULL
)
2041 bool is_exec
= parameters
->options().output_is_executable();
2042 symtab
->define_in_output_segment("_TLS_MODULE_BASE_", NULL
,
2043 Symbol_table::PREDEFINED
,
2047 elfcpp::STV_HIDDEN
, 0,
2049 ? Symbol::SEGMENT_END
2050 : Symbol::SEGMENT_START
),
2053 this->tls_base_symbol_defined_
= true;
2056 // Create the reserved PLT and GOT entries for the TLS descriptor resolver.
2060 Target_x86_64
<size
>::reserve_tlsdesc_entries(Symbol_table
* symtab
,
2063 if (this->plt_
== NULL
)
2064 this->make_plt_section(symtab
, layout
);
2066 if (!this->plt_
->has_tlsdesc_entry())
2068 // Allocate the TLSDESC_GOT entry.
2069 Output_data_got
<64, false>* got
= this->got_section(symtab
, layout
);
2070 unsigned int got_offset
= got
->add_constant(0);
2072 // Allocate the TLSDESC_PLT entry.
2073 this->plt_
->reserve_tlsdesc_entry(got_offset
);
2077 // Create a GOT entry for the TLS module index.
2081 Target_x86_64
<size
>::got_mod_index_entry(Symbol_table
* symtab
, Layout
* layout
,
2082 Sized_relobj_file
<size
, false>* object
)
2084 if (this->got_mod_index_offset_
== -1U)
2086 gold_assert(symtab
!= NULL
&& layout
!= NULL
&& object
!= NULL
);
2087 Reloc_section
* rela_dyn
= this->rela_dyn_section(layout
);
2088 Output_data_got
<64, false>* got
= this->got_section(symtab
, layout
);
2089 unsigned int got_offset
= got
->add_constant(0);
2090 rela_dyn
->add_local(object
, 0, elfcpp::R_X86_64_DTPMOD64
, got
,
2092 got
->add_constant(0);
2093 this->got_mod_index_offset_
= got_offset
;
2095 return this->got_mod_index_offset_
;
2098 // Optimize the TLS relocation type based on what we know about the
2099 // symbol. IS_FINAL is true if the final address of this symbol is
2100 // known at link time.
2103 tls::Tls_optimization
2104 Target_x86_64
<size
>::optimize_tls_reloc(bool is_final
, int r_type
)
2106 // If we are generating a shared library, then we can't do anything
2108 if (parameters
->options().shared())
2109 return tls::TLSOPT_NONE
;
2113 case elfcpp::R_X86_64_TLSGD
:
2114 case elfcpp::R_X86_64_GOTPC32_TLSDESC
:
2115 case elfcpp::R_X86_64_TLSDESC_CALL
:
2116 // These are General-Dynamic which permits fully general TLS
2117 // access. Since we know that we are generating an executable,
2118 // we can convert this to Initial-Exec. If we also know that
2119 // this is a local symbol, we can further switch to Local-Exec.
2121 return tls::TLSOPT_TO_LE
;
2122 return tls::TLSOPT_TO_IE
;
2124 case elfcpp::R_X86_64_TLSLD
:
2125 // This is Local-Dynamic, which refers to a local symbol in the
2126 // dynamic TLS block. Since we know that we generating an
2127 // executable, we can switch to Local-Exec.
2128 return tls::TLSOPT_TO_LE
;
2130 case elfcpp::R_X86_64_DTPOFF32
:
2131 case elfcpp::R_X86_64_DTPOFF64
:
2132 // Another Local-Dynamic reloc.
2133 return tls::TLSOPT_TO_LE
;
2135 case elfcpp::R_X86_64_GOTTPOFF
:
2136 // These are Initial-Exec relocs which get the thread offset
2137 // from the GOT. If we know that we are linking against the
2138 // local symbol, we can switch to Local-Exec, which links the
2139 // thread offset into the instruction.
2141 return tls::TLSOPT_TO_LE
;
2142 return tls::TLSOPT_NONE
;
2144 case elfcpp::R_X86_64_TPOFF32
:
2145 // When we already have Local-Exec, there is nothing further we
2147 return tls::TLSOPT_NONE
;
2154 // Get the Reference_flags for a particular relocation.
2158 Target_x86_64
<size
>::Scan::get_reference_flags(unsigned int r_type
)
2162 case elfcpp::R_X86_64_NONE
:
2163 case elfcpp::R_X86_64_GNU_VTINHERIT
:
2164 case elfcpp::R_X86_64_GNU_VTENTRY
:
2165 case elfcpp::R_X86_64_GOTPC32
:
2166 case elfcpp::R_X86_64_GOTPC64
:
2167 // No symbol reference.
2170 case elfcpp::R_X86_64_64
:
2171 case elfcpp::R_X86_64_32
:
2172 case elfcpp::R_X86_64_32S
:
2173 case elfcpp::R_X86_64_16
:
2174 case elfcpp::R_X86_64_8
:
2175 return Symbol::ABSOLUTE_REF
;
2177 case elfcpp::R_X86_64_PC64
:
2178 case elfcpp::R_X86_64_PC32
:
2179 case elfcpp::R_X86_64_PC32_BND
:
2180 case elfcpp::R_X86_64_PC16
:
2181 case elfcpp::R_X86_64_PC8
:
2182 case elfcpp::R_X86_64_GOTOFF64
:
2183 return Symbol::RELATIVE_REF
;
2185 case elfcpp::R_X86_64_PLT32
:
2186 case elfcpp::R_X86_64_PLT32_BND
:
2187 case elfcpp::R_X86_64_PLTOFF64
:
2188 return Symbol::FUNCTION_CALL
| Symbol::RELATIVE_REF
;
2190 case elfcpp::R_X86_64_GOT64
:
2191 case elfcpp::R_X86_64_GOT32
:
2192 case elfcpp::R_X86_64_GOTPCREL64
:
2193 case elfcpp::R_X86_64_GOTPCREL
:
2194 case elfcpp::R_X86_64_GOTPLT64
:
2196 return Symbol::ABSOLUTE_REF
;
2198 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
2199 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
2200 case elfcpp::R_X86_64_TLSDESC_CALL
:
2201 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
2202 case elfcpp::R_X86_64_DTPOFF32
:
2203 case elfcpp::R_X86_64_DTPOFF64
:
2204 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
2205 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
2206 return Symbol::TLS_REF
;
2208 case elfcpp::R_X86_64_COPY
:
2209 case elfcpp::R_X86_64_GLOB_DAT
:
2210 case elfcpp::R_X86_64_JUMP_SLOT
:
2211 case elfcpp::R_X86_64_RELATIVE
:
2212 case elfcpp::R_X86_64_IRELATIVE
:
2213 case elfcpp::R_X86_64_TPOFF64
:
2214 case elfcpp::R_X86_64_DTPMOD64
:
2215 case elfcpp::R_X86_64_TLSDESC
:
2216 case elfcpp::R_X86_64_SIZE32
:
2217 case elfcpp::R_X86_64_SIZE64
:
2219 // Not expected. We will give an error later.
2224 // Report an unsupported relocation against a local symbol.
2228 Target_x86_64
<size
>::Scan::unsupported_reloc_local(
2229 Sized_relobj_file
<size
, false>* object
,
2230 unsigned int r_type
)
2232 gold_error(_("%s: unsupported reloc %u against local symbol"),
2233 object
->name().c_str(), r_type
);
2236 // We are about to emit a dynamic relocation of type R_TYPE. If the
2237 // dynamic linker does not support it, issue an error. The GNU linker
2238 // only issues a non-PIC error for an allocated read-only section.
2239 // Here we know the section is allocated, but we don't know that it is
2240 // read-only. But we check for all the relocation types which the
2241 // glibc dynamic linker supports, so it seems appropriate to issue an
2242 // error even if the section is not read-only. If GSYM is not NULL,
2243 // it is the symbol the relocation is against; if it is NULL, the
2244 // relocation is against a local symbol.
2248 Target_x86_64
<size
>::Scan::check_non_pic(Relobj
* object
, unsigned int r_type
,
2253 // These are the relocation types supported by glibc for x86_64
2254 // which should always work.
2255 case elfcpp::R_X86_64_RELATIVE
:
2256 case elfcpp::R_X86_64_IRELATIVE
:
2257 case elfcpp::R_X86_64_GLOB_DAT
:
2258 case elfcpp::R_X86_64_JUMP_SLOT
:
2259 case elfcpp::R_X86_64_DTPMOD64
:
2260 case elfcpp::R_X86_64_DTPOFF64
:
2261 case elfcpp::R_X86_64_TPOFF64
:
2262 case elfcpp::R_X86_64_64
:
2263 case elfcpp::R_X86_64_COPY
:
2266 // glibc supports these reloc types, but they can overflow.
2267 case elfcpp::R_X86_64_PC32
:
2268 case elfcpp::R_X86_64_PC32_BND
:
2269 // A PC relative reference is OK against a local symbol or if
2270 // the symbol is defined locally.
2272 || (!gsym
->is_from_dynobj()
2273 && !gsym
->is_undefined()
2274 && !gsym
->is_preemptible()))
2277 case elfcpp::R_X86_64_32
:
2278 // R_X86_64_32 is OK for x32.
2279 if (size
== 32 && r_type
== elfcpp::R_X86_64_32
)
2281 if (this->issued_non_pic_error_
)
2283 gold_assert(parameters
->options().output_is_position_independent());
2285 object
->error(_("requires dynamic R_X86_64_32 reloc which may "
2286 "overflow at runtime; recompile with -fPIC"));
2292 case elfcpp::R_X86_64_32
:
2293 r_name
= "R_X86_64_32";
2295 case elfcpp::R_X86_64_PC32
:
2296 r_name
= "R_X86_64_PC32";
2298 case elfcpp::R_X86_64_PC32_BND
:
2299 r_name
= "R_X86_64_PC32_BND";
2305 object
->error(_("requires dynamic %s reloc against '%s' "
2306 "which may overflow at runtime; recompile "
2308 r_name
, gsym
->name());
2310 this->issued_non_pic_error_
= true;
2314 // This prevents us from issuing more than one error per reloc
2315 // section. But we can still wind up issuing more than one
2316 // error per object file.
2317 if (this->issued_non_pic_error_
)
2319 gold_assert(parameters
->options().output_is_position_independent());
2320 object
->error(_("requires unsupported dynamic reloc %u; "
2321 "recompile with -fPIC"),
2323 this->issued_non_pic_error_
= true;
2326 case elfcpp::R_X86_64_NONE
:
2331 // Return whether we need to make a PLT entry for a relocation of the
2332 // given type against a STT_GNU_IFUNC symbol.
2336 Target_x86_64
<size
>::Scan::reloc_needs_plt_for_ifunc(
2337 Sized_relobj_file
<size
, false>* object
,
2338 unsigned int r_type
)
2340 int flags
= Scan::get_reference_flags(r_type
);
2341 if (flags
& Symbol::TLS_REF
)
2342 gold_error(_("%s: unsupported TLS reloc %u for IFUNC symbol"),
2343 object
->name().c_str(), r_type
);
2347 // Scan a relocation for a local symbol.
2351 Target_x86_64
<size
>::Scan::local(Symbol_table
* symtab
,
2353 Target_x86_64
<size
>* target
,
2354 Sized_relobj_file
<size
, false>* object
,
2355 unsigned int data_shndx
,
2356 Output_section
* output_section
,
2357 const elfcpp::Rela
<size
, false>& reloc
,
2358 unsigned int r_type
,
2359 const elfcpp::Sym
<size
, false>& lsym
,
2365 // A local STT_GNU_IFUNC symbol may require a PLT entry.
2366 bool is_ifunc
= lsym
.get_st_type() == elfcpp::STT_GNU_IFUNC
;
2367 if (is_ifunc
&& this->reloc_needs_plt_for_ifunc(object
, r_type
))
2369 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(reloc
.get_r_info());
2370 target
->make_local_ifunc_plt_entry(symtab
, layout
, object
, r_sym
);
2375 case elfcpp::R_X86_64_NONE
:
2376 case elfcpp::R_X86_64_GNU_VTINHERIT
:
2377 case elfcpp::R_X86_64_GNU_VTENTRY
:
2380 case elfcpp::R_X86_64_64
:
2381 // If building a shared library (or a position-independent
2382 // executable), we need to create a dynamic relocation for this
2383 // location. The relocation applied at link time will apply the
2384 // link-time value, so we flag the location with an
2385 // R_X86_64_RELATIVE relocation so the dynamic loader can
2386 // relocate it easily.
2387 if (parameters
->options().output_is_position_independent())
2389 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(reloc
.get_r_info());
2390 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
2391 rela_dyn
->add_local_relative(object
, r_sym
,
2393 ? elfcpp::R_X86_64_RELATIVE64
2394 : elfcpp::R_X86_64_RELATIVE
),
2395 output_section
, data_shndx
,
2396 reloc
.get_r_offset(),
2397 reloc
.get_r_addend(), is_ifunc
);
2401 case elfcpp::R_X86_64_32
:
2402 case elfcpp::R_X86_64_32S
:
2403 case elfcpp::R_X86_64_16
:
2404 case elfcpp::R_X86_64_8
:
2405 // If building a shared library (or a position-independent
2406 // executable), we need to create a dynamic relocation for this
2407 // location. We can't use an R_X86_64_RELATIVE relocation
2408 // because that is always a 64-bit relocation.
2409 if (parameters
->options().output_is_position_independent())
2411 // Use R_X86_64_RELATIVE relocation for R_X86_64_32 under x32.
2412 if (size
== 32 && r_type
== elfcpp::R_X86_64_32
)
2414 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(reloc
.get_r_info());
2415 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
2416 rela_dyn
->add_local_relative(object
, r_sym
,
2417 elfcpp::R_X86_64_RELATIVE
,
2418 output_section
, data_shndx
,
2419 reloc
.get_r_offset(),
2420 reloc
.get_r_addend(), is_ifunc
);
2424 this->check_non_pic(object
, r_type
, NULL
);
2426 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
2427 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(reloc
.get_r_info());
2428 if (lsym
.get_st_type() != elfcpp::STT_SECTION
)
2429 rela_dyn
->add_local(object
, r_sym
, r_type
, output_section
,
2430 data_shndx
, reloc
.get_r_offset(),
2431 reloc
.get_r_addend());
2434 gold_assert(lsym
.get_st_value() == 0);
2435 unsigned int shndx
= lsym
.get_st_shndx();
2437 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
,
2440 object
->error(_("section symbol %u has bad shndx %u"),
2443 rela_dyn
->add_local_section(object
, shndx
,
2444 r_type
, output_section
,
2445 data_shndx
, reloc
.get_r_offset(),
2446 reloc
.get_r_addend());
2451 case elfcpp::R_X86_64_PC64
:
2452 case elfcpp::R_X86_64_PC32
:
2453 case elfcpp::R_X86_64_PC32_BND
:
2454 case elfcpp::R_X86_64_PC16
:
2455 case elfcpp::R_X86_64_PC8
:
2458 case elfcpp::R_X86_64_PLT32
:
2459 case elfcpp::R_X86_64_PLT32_BND
:
2460 // Since we know this is a local symbol, we can handle this as a
2464 case elfcpp::R_X86_64_GOTPC32
:
2465 case elfcpp::R_X86_64_GOTOFF64
:
2466 case elfcpp::R_X86_64_GOTPC64
:
2467 case elfcpp::R_X86_64_PLTOFF64
:
2468 // We need a GOT section.
2469 target
->got_section(symtab
, layout
);
2470 // For PLTOFF64, we'd normally want a PLT section, but since we
2471 // know this is a local symbol, no PLT is needed.
2474 case elfcpp::R_X86_64_GOT64
:
2475 case elfcpp::R_X86_64_GOT32
:
2476 case elfcpp::R_X86_64_GOTPCREL64
:
2477 case elfcpp::R_X86_64_GOTPCREL
:
2478 case elfcpp::R_X86_64_GOTPLT64
:
2480 // The symbol requires a GOT section.
2481 Output_data_got
<64, false>* got
= target
->got_section(symtab
, layout
);
2483 // If the relocation symbol isn't IFUNC,
2484 // and is local, then we will convert
2485 // mov foo@GOTPCREL(%rip), %reg
2486 // to lea foo(%rip), %reg.
2487 // in Relocate::relocate.
2488 if (r_type
== elfcpp::R_X86_64_GOTPCREL
2489 && reloc
.get_r_offset() >= 2
2492 section_size_type stype
;
2493 const unsigned char* view
= object
->section_contents(data_shndx
,
2495 if (view
[reloc
.get_r_offset() - 2] == 0x8b)
2500 // The symbol requires a GOT entry.
2501 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(reloc
.get_r_info());
2503 // For a STT_GNU_IFUNC symbol we want the PLT offset. That
2504 // lets function pointers compare correctly with shared
2505 // libraries. Otherwise we would need an IRELATIVE reloc.
2508 is_new
= got
->add_local_plt(object
, r_sym
, GOT_TYPE_STANDARD
);
2510 is_new
= got
->add_local(object
, r_sym
, GOT_TYPE_STANDARD
);
2513 // If we are generating a shared object, we need to add a
2514 // dynamic relocation for this symbol's GOT entry.
2515 if (parameters
->options().output_is_position_independent())
2517 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
2518 // R_X86_64_RELATIVE assumes a 64-bit relocation.
2519 if (r_type
!= elfcpp::R_X86_64_GOT32
)
2521 unsigned int got_offset
=
2522 object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
);
2523 rela_dyn
->add_local_relative(object
, r_sym
,
2524 elfcpp::R_X86_64_RELATIVE
,
2525 got
, got_offset
, 0, is_ifunc
);
2529 this->check_non_pic(object
, r_type
, NULL
);
2531 gold_assert(lsym
.get_st_type() != elfcpp::STT_SECTION
);
2532 rela_dyn
->add_local(
2533 object
, r_sym
, r_type
, got
,
2534 object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
), 0);
2538 // For GOTPLT64, we'd normally want a PLT section, but since
2539 // we know this is a local symbol, no PLT is needed.
2543 case elfcpp::R_X86_64_COPY
:
2544 case elfcpp::R_X86_64_GLOB_DAT
:
2545 case elfcpp::R_X86_64_JUMP_SLOT
:
2546 case elfcpp::R_X86_64_RELATIVE
:
2547 case elfcpp::R_X86_64_IRELATIVE
:
2548 // These are outstanding tls relocs, which are unexpected when linking
2549 case elfcpp::R_X86_64_TPOFF64
:
2550 case elfcpp::R_X86_64_DTPMOD64
:
2551 case elfcpp::R_X86_64_TLSDESC
:
2552 gold_error(_("%s: unexpected reloc %u in object file"),
2553 object
->name().c_str(), r_type
);
2556 // These are initial tls relocs, which are expected when linking
2557 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
2558 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
2559 case elfcpp::R_X86_64_TLSDESC_CALL
:
2560 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
2561 case elfcpp::R_X86_64_DTPOFF32
:
2562 case elfcpp::R_X86_64_DTPOFF64
:
2563 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
2564 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
2566 bool output_is_shared
= parameters
->options().shared();
2567 const tls::Tls_optimization optimized_type
2568 = Target_x86_64
<size
>::optimize_tls_reloc(!output_is_shared
,
2572 case elfcpp::R_X86_64_TLSGD
: // General-dynamic
2573 if (optimized_type
== tls::TLSOPT_NONE
)
2575 // Create a pair of GOT entries for the module index and
2576 // dtv-relative offset.
2577 Output_data_got
<64, false>* got
2578 = target
->got_section(symtab
, layout
);
2579 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(reloc
.get_r_info());
2580 unsigned int shndx
= lsym
.get_st_shndx();
2582 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
, &is_ordinary
);
2584 object
->error(_("local symbol %u has bad shndx %u"),
2587 got
->add_local_pair_with_rel(object
, r_sym
,
2590 target
->rela_dyn_section(layout
),
2591 elfcpp::R_X86_64_DTPMOD64
);
2593 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2594 unsupported_reloc_local(object
, r_type
);
2597 case elfcpp::R_X86_64_GOTPC32_TLSDESC
:
2598 target
->define_tls_base_symbol(symtab
, layout
);
2599 if (optimized_type
== tls::TLSOPT_NONE
)
2601 // Create reserved PLT and GOT entries for the resolver.
2602 target
->reserve_tlsdesc_entries(symtab
, layout
);
2604 // Generate a double GOT entry with an
2605 // R_X86_64_TLSDESC reloc. The R_X86_64_TLSDESC reloc
2606 // is resolved lazily, so the GOT entry needs to be in
2607 // an area in .got.plt, not .got. Call got_section to
2608 // make sure the section has been created.
2609 target
->got_section(symtab
, layout
);
2610 Output_data_got
<64, false>* got
= target
->got_tlsdesc_section();
2611 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(reloc
.get_r_info());
2612 if (!object
->local_has_got_offset(r_sym
, GOT_TYPE_TLS_DESC
))
2614 unsigned int got_offset
= got
->add_constant(0);
2615 got
->add_constant(0);
2616 object
->set_local_got_offset(r_sym
, GOT_TYPE_TLS_DESC
,
2618 Reloc_section
* rt
= target
->rela_tlsdesc_section(layout
);
2619 // We store the arguments we need in a vector, and
2620 // use the index into the vector as the parameter
2621 // to pass to the target specific routines.
2622 uintptr_t intarg
= target
->add_tlsdesc_info(object
, r_sym
);
2623 void* arg
= reinterpret_cast<void*>(intarg
);
2624 rt
->add_target_specific(elfcpp::R_X86_64_TLSDESC
, arg
,
2625 got
, got_offset
, 0);
2628 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2629 unsupported_reloc_local(object
, r_type
);
2632 case elfcpp::R_X86_64_TLSDESC_CALL
:
2635 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
2636 if (optimized_type
== tls::TLSOPT_NONE
)
2638 // Create a GOT entry for the module index.
2639 target
->got_mod_index_entry(symtab
, layout
, object
);
2641 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2642 unsupported_reloc_local(object
, r_type
);
2645 case elfcpp::R_X86_64_DTPOFF32
:
2646 case elfcpp::R_X86_64_DTPOFF64
:
2649 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
2650 layout
->set_has_static_tls();
2651 if (optimized_type
== tls::TLSOPT_NONE
)
2653 // Create a GOT entry for the tp-relative offset.
2654 Output_data_got
<64, false>* got
2655 = target
->got_section(symtab
, layout
);
2656 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(reloc
.get_r_info());
2657 got
->add_local_with_rel(object
, r_sym
, GOT_TYPE_TLS_OFFSET
,
2658 target
->rela_dyn_section(layout
),
2659 elfcpp::R_X86_64_TPOFF64
);
2661 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2662 unsupported_reloc_local(object
, r_type
);
2665 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
2666 layout
->set_has_static_tls();
2667 if (output_is_shared
)
2668 unsupported_reloc_local(object
, r_type
);
2677 case elfcpp::R_X86_64_SIZE32
:
2678 case elfcpp::R_X86_64_SIZE64
:
2680 gold_error(_("%s: unsupported reloc %u against local symbol"),
2681 object
->name().c_str(), r_type
);
2687 // Report an unsupported relocation against a global symbol.
2691 Target_x86_64
<size
>::Scan::unsupported_reloc_global(
2692 Sized_relobj_file
<size
, false>* object
,
2693 unsigned int r_type
,
2696 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
2697 object
->name().c_str(), r_type
, gsym
->demangled_name().c_str());
2700 // Returns true if this relocation type could be that of a function pointer.
2703 Target_x86_64
<size
>::Scan::possible_function_pointer_reloc(unsigned int r_type
)
2707 case elfcpp::R_X86_64_64
:
2708 case elfcpp::R_X86_64_32
:
2709 case elfcpp::R_X86_64_32S
:
2710 case elfcpp::R_X86_64_16
:
2711 case elfcpp::R_X86_64_8
:
2712 case elfcpp::R_X86_64_GOT64
:
2713 case elfcpp::R_X86_64_GOT32
:
2714 case elfcpp::R_X86_64_GOTPCREL64
:
2715 case elfcpp::R_X86_64_GOTPCREL
:
2716 case elfcpp::R_X86_64_GOTPLT64
:
2724 // For safe ICF, scan a relocation for a local symbol to check if it
2725 // corresponds to a function pointer being taken. In that case mark
2726 // the function whose pointer was taken as not foldable.
2730 Target_x86_64
<size
>::Scan::local_reloc_may_be_function_pointer(
2733 Target_x86_64
<size
>* ,
2734 Sized_relobj_file
<size
, false>* ,
2737 const elfcpp::Rela
<size
, false>& ,
2738 unsigned int r_type
,
2739 const elfcpp::Sym
<size
, false>&)
2741 // When building a shared library, do not fold any local symbols as it is
2742 // not possible to distinguish pointer taken versus a call by looking at
2743 // the relocation types.
2744 return (parameters
->options().shared()
2745 || possible_function_pointer_reloc(r_type
));
2748 // For safe ICF, scan a relocation for a global symbol to check if it
2749 // corresponds to a function pointer being taken. In that case mark
2750 // the function whose pointer was taken as not foldable.
2754 Target_x86_64
<size
>::Scan::global_reloc_may_be_function_pointer(
2757 Target_x86_64
<size
>* ,
2758 Sized_relobj_file
<size
, false>* ,
2761 const elfcpp::Rela
<size
, false>& ,
2762 unsigned int r_type
,
2765 // When building a shared library, do not fold symbols whose visibility
2766 // is hidden, internal or protected.
2767 return ((parameters
->options().shared()
2768 && (gsym
->visibility() == elfcpp::STV_INTERNAL
2769 || gsym
->visibility() == elfcpp::STV_PROTECTED
2770 || gsym
->visibility() == elfcpp::STV_HIDDEN
))
2771 || possible_function_pointer_reloc(r_type
));
2774 // Scan a relocation for a global symbol.
2778 Target_x86_64
<size
>::Scan::global(Symbol_table
* symtab
,
2780 Target_x86_64
<size
>* target
,
2781 Sized_relobj_file
<size
, false>* object
,
2782 unsigned int data_shndx
,
2783 Output_section
* output_section
,
2784 const elfcpp::Rela
<size
, false>& reloc
,
2785 unsigned int r_type
,
2788 // A STT_GNU_IFUNC symbol may require a PLT entry.
2789 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
2790 && this->reloc_needs_plt_for_ifunc(object
, r_type
))
2791 target
->make_plt_entry(symtab
, layout
, gsym
);
2795 case elfcpp::R_X86_64_NONE
:
2796 case elfcpp::R_X86_64_GNU_VTINHERIT
:
2797 case elfcpp::R_X86_64_GNU_VTENTRY
:
2800 case elfcpp::R_X86_64_64
:
2801 case elfcpp::R_X86_64_32
:
2802 case elfcpp::R_X86_64_32S
:
2803 case elfcpp::R_X86_64_16
:
2804 case elfcpp::R_X86_64_8
:
2806 // Make a PLT entry if necessary.
2807 if (gsym
->needs_plt_entry())
2809 target
->make_plt_entry(symtab
, layout
, gsym
);
2810 // Since this is not a PC-relative relocation, we may be
2811 // taking the address of a function. In that case we need to
2812 // set the entry in the dynamic symbol table to the address of
2814 if (gsym
->is_from_dynobj() && !parameters
->options().shared())
2815 gsym
->set_needs_dynsym_value();
2817 // Make a dynamic relocation if necessary.
2818 if (gsym
->needs_dynamic_reloc(Scan::get_reference_flags(r_type
)))
2820 if (!parameters
->options().output_is_position_independent()
2821 && gsym
->may_need_copy_reloc())
2823 target
->copy_reloc(symtab
, layout
, object
,
2824 data_shndx
, output_section
, gsym
, reloc
);
2826 else if (((size
== 64 && r_type
== elfcpp::R_X86_64_64
)
2827 || (size
== 32 && r_type
== elfcpp::R_X86_64_32
))
2828 && gsym
->type() == elfcpp::STT_GNU_IFUNC
2829 && gsym
->can_use_relative_reloc(false)
2830 && !gsym
->is_from_dynobj()
2831 && !gsym
->is_undefined()
2832 && !gsym
->is_preemptible())
2834 // Use an IRELATIVE reloc for a locally defined
2835 // STT_GNU_IFUNC symbol. This makes a function
2836 // address in a PIE executable match the address in a
2837 // shared library that it links against.
2838 Reloc_section
* rela_dyn
=
2839 target
->rela_irelative_section(layout
);
2840 unsigned int r_type
= elfcpp::R_X86_64_IRELATIVE
;
2841 rela_dyn
->add_symbolless_global_addend(gsym
, r_type
,
2842 output_section
, object
,
2844 reloc
.get_r_offset(),
2845 reloc
.get_r_addend());
2847 else if (((size
== 64 && r_type
== elfcpp::R_X86_64_64
)
2848 || (size
== 32 && r_type
== elfcpp::R_X86_64_32
))
2849 && gsym
->can_use_relative_reloc(false))
2851 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
2852 rela_dyn
->add_global_relative(gsym
, elfcpp::R_X86_64_RELATIVE
,
2853 output_section
, object
,
2855 reloc
.get_r_offset(),
2856 reloc
.get_r_addend(), false);
2860 this->check_non_pic(object
, r_type
, gsym
);
2861 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
2862 rela_dyn
->add_global(gsym
, r_type
, output_section
, object
,
2863 data_shndx
, reloc
.get_r_offset(),
2864 reloc
.get_r_addend());
2870 case elfcpp::R_X86_64_PC64
:
2871 case elfcpp::R_X86_64_PC32
:
2872 case elfcpp::R_X86_64_PC32_BND
:
2873 case elfcpp::R_X86_64_PC16
:
2874 case elfcpp::R_X86_64_PC8
:
2876 // Make a PLT entry if necessary.
2877 if (gsym
->needs_plt_entry())
2878 target
->make_plt_entry(symtab
, layout
, gsym
);
2879 // Make a dynamic relocation if necessary.
2880 if (gsym
->needs_dynamic_reloc(Scan::get_reference_flags(r_type
)))
2882 if (parameters
->options().output_is_executable()
2883 && gsym
->may_need_copy_reloc())
2885 target
->copy_reloc(symtab
, layout
, object
,
2886 data_shndx
, output_section
, gsym
, reloc
);
2890 this->check_non_pic(object
, r_type
, gsym
);
2891 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
2892 rela_dyn
->add_global(gsym
, r_type
, output_section
, object
,
2893 data_shndx
, reloc
.get_r_offset(),
2894 reloc
.get_r_addend());
2900 case elfcpp::R_X86_64_GOT64
:
2901 case elfcpp::R_X86_64_GOT32
:
2902 case elfcpp::R_X86_64_GOTPCREL64
:
2903 case elfcpp::R_X86_64_GOTPCREL
:
2904 case elfcpp::R_X86_64_GOTPLT64
:
2906 // The symbol requires a GOT entry.
2907 Output_data_got
<64, false>* got
= target
->got_section(symtab
, layout
);
2909 // If we convert this from
2910 // mov foo@GOTPCREL(%rip), %reg
2911 // to lea foo(%rip), %reg.
2912 // in Relocate::relocate, then there is nothing to do here.
2913 if (r_type
== elfcpp::R_X86_64_GOTPCREL
2914 && reloc
.get_r_offset() >= 2
2915 && Target_x86_64
<size
>::can_convert_mov_to_lea(gsym
))
2917 section_size_type stype
;
2918 const unsigned char* view
= object
->section_contents(data_shndx
,
2920 if (view
[reloc
.get_r_offset() - 2] == 0x8b)
2924 if (gsym
->final_value_is_known())
2926 // For a STT_GNU_IFUNC symbol we want the PLT address.
2927 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
)
2928 got
->add_global_plt(gsym
, GOT_TYPE_STANDARD
);
2930 got
->add_global(gsym
, GOT_TYPE_STANDARD
);
2934 // If this symbol is not fully resolved, we need to add a
2935 // dynamic relocation for it.
2936 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
2938 // Use a GLOB_DAT rather than a RELATIVE reloc if:
2940 // 1) The symbol may be defined in some other module.
2942 // 2) We are building a shared library and this is a
2943 // protected symbol; using GLOB_DAT means that the dynamic
2944 // linker can use the address of the PLT in the main
2945 // executable when appropriate so that function address
2946 // comparisons work.
2948 // 3) This is a STT_GNU_IFUNC symbol in position dependent
2949 // code, again so that function address comparisons work.
2950 if (gsym
->is_from_dynobj()
2951 || gsym
->is_undefined()
2952 || gsym
->is_preemptible()
2953 || (gsym
->visibility() == elfcpp::STV_PROTECTED
2954 && parameters
->options().shared())
2955 || (gsym
->type() == elfcpp::STT_GNU_IFUNC
2956 && parameters
->options().output_is_position_independent()))
2957 got
->add_global_with_rel(gsym
, GOT_TYPE_STANDARD
, rela_dyn
,
2958 elfcpp::R_X86_64_GLOB_DAT
);
2961 // For a STT_GNU_IFUNC symbol we want to write the PLT
2962 // offset into the GOT, so that function pointer
2963 // comparisons work correctly.
2965 if (gsym
->type() != elfcpp::STT_GNU_IFUNC
)
2966 is_new
= got
->add_global(gsym
, GOT_TYPE_STANDARD
);
2969 is_new
= got
->add_global_plt(gsym
, GOT_TYPE_STANDARD
);
2970 // Tell the dynamic linker to use the PLT address
2971 // when resolving relocations.
2972 if (gsym
->is_from_dynobj()
2973 && !parameters
->options().shared())
2974 gsym
->set_needs_dynsym_value();
2978 unsigned int got_off
= gsym
->got_offset(GOT_TYPE_STANDARD
);
2979 rela_dyn
->add_global_relative(gsym
,
2980 elfcpp::R_X86_64_RELATIVE
,
2981 got
, got_off
, 0, false);
2988 case elfcpp::R_X86_64_PLT32
:
2989 case elfcpp::R_X86_64_PLT32_BND
:
2990 // If the symbol is fully resolved, this is just a PC32 reloc.
2991 // Otherwise we need a PLT entry.
2992 if (gsym
->final_value_is_known())
2994 // If building a shared library, we can also skip the PLT entry
2995 // if the symbol is defined in the output file and is protected
2997 if (gsym
->is_defined()
2998 && !gsym
->is_from_dynobj()
2999 && !gsym
->is_preemptible())
3001 target
->make_plt_entry(symtab
, layout
, gsym
);
3004 case elfcpp::R_X86_64_GOTPC32
:
3005 case elfcpp::R_X86_64_GOTOFF64
:
3006 case elfcpp::R_X86_64_GOTPC64
:
3007 case elfcpp::R_X86_64_PLTOFF64
:
3008 // We need a GOT section.
3009 target
->got_section(symtab
, layout
);
3010 // For PLTOFF64, we also need a PLT entry (but only if the
3011 // symbol is not fully resolved).
3012 if (r_type
== elfcpp::R_X86_64_PLTOFF64
3013 && !gsym
->final_value_is_known())
3014 target
->make_plt_entry(symtab
, layout
, gsym
);
3017 case elfcpp::R_X86_64_COPY
:
3018 case elfcpp::R_X86_64_GLOB_DAT
:
3019 case elfcpp::R_X86_64_JUMP_SLOT
:
3020 case elfcpp::R_X86_64_RELATIVE
:
3021 case elfcpp::R_X86_64_IRELATIVE
:
3022 // These are outstanding tls relocs, which are unexpected when linking
3023 case elfcpp::R_X86_64_TPOFF64
:
3024 case elfcpp::R_X86_64_DTPMOD64
:
3025 case elfcpp::R_X86_64_TLSDESC
:
3026 gold_error(_("%s: unexpected reloc %u in object file"),
3027 object
->name().c_str(), r_type
);
3030 // These are initial tls relocs, which are expected for global()
3031 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
3032 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
3033 case elfcpp::R_X86_64_TLSDESC_CALL
:
3034 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
3035 case elfcpp::R_X86_64_DTPOFF32
:
3036 case elfcpp::R_X86_64_DTPOFF64
:
3037 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
3038 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
3040 // For the Initial-Exec model, we can treat undef symbols as final
3041 // when building an executable.
3042 const bool is_final
= (gsym
->final_value_is_known() ||
3043 (r_type
== elfcpp::R_X86_64_GOTTPOFF
&&
3044 gsym
->is_undefined() &&
3045 parameters
->options().output_is_executable()));
3046 const tls::Tls_optimization optimized_type
3047 = Target_x86_64
<size
>::optimize_tls_reloc(is_final
, r_type
);
3050 case elfcpp::R_X86_64_TLSGD
: // General-dynamic
3051 if (optimized_type
== tls::TLSOPT_NONE
)
3053 // Create a pair of GOT entries for the module index and
3054 // dtv-relative offset.
3055 Output_data_got
<64, false>* got
3056 = target
->got_section(symtab
, layout
);
3057 got
->add_global_pair_with_rel(gsym
, GOT_TYPE_TLS_PAIR
,
3058 target
->rela_dyn_section(layout
),
3059 elfcpp::R_X86_64_DTPMOD64
,
3060 elfcpp::R_X86_64_DTPOFF64
);
3062 else if (optimized_type
== tls::TLSOPT_TO_IE
)
3064 // Create a GOT entry for the tp-relative offset.
3065 Output_data_got
<64, false>* got
3066 = target
->got_section(symtab
, layout
);
3067 got
->add_global_with_rel(gsym
, GOT_TYPE_TLS_OFFSET
,
3068 target
->rela_dyn_section(layout
),
3069 elfcpp::R_X86_64_TPOFF64
);
3071 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
3072 unsupported_reloc_global(object
, r_type
, gsym
);
3075 case elfcpp::R_X86_64_GOTPC32_TLSDESC
:
3076 target
->define_tls_base_symbol(symtab
, layout
);
3077 if (optimized_type
== tls::TLSOPT_NONE
)
3079 // Create reserved PLT and GOT entries for the resolver.
3080 target
->reserve_tlsdesc_entries(symtab
, layout
);
3082 // Create a double GOT entry with an R_X86_64_TLSDESC
3083 // reloc. The R_X86_64_TLSDESC reloc is resolved
3084 // lazily, so the GOT entry needs to be in an area in
3085 // .got.plt, not .got. Call got_section to make sure
3086 // the section has been created.
3087 target
->got_section(symtab
, layout
);
3088 Output_data_got
<64, false>* got
= target
->got_tlsdesc_section();
3089 Reloc_section
* rt
= target
->rela_tlsdesc_section(layout
);
3090 got
->add_global_pair_with_rel(gsym
, GOT_TYPE_TLS_DESC
, rt
,
3091 elfcpp::R_X86_64_TLSDESC
, 0);
3093 else if (optimized_type
== tls::TLSOPT_TO_IE
)
3095 // Create a GOT entry for the tp-relative offset.
3096 Output_data_got
<64, false>* got
3097 = target
->got_section(symtab
, layout
);
3098 got
->add_global_with_rel(gsym
, GOT_TYPE_TLS_OFFSET
,
3099 target
->rela_dyn_section(layout
),
3100 elfcpp::R_X86_64_TPOFF64
);
3102 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
3103 unsupported_reloc_global(object
, r_type
, gsym
);
3106 case elfcpp::R_X86_64_TLSDESC_CALL
:
3109 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
3110 if (optimized_type
== tls::TLSOPT_NONE
)
3112 // Create a GOT entry for the module index.
3113 target
->got_mod_index_entry(symtab
, layout
, object
);
3115 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
3116 unsupported_reloc_global(object
, r_type
, gsym
);
3119 case elfcpp::R_X86_64_DTPOFF32
:
3120 case elfcpp::R_X86_64_DTPOFF64
:
3123 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
3124 layout
->set_has_static_tls();
3125 if (optimized_type
== tls::TLSOPT_NONE
)
3127 // Create a GOT entry for the tp-relative offset.
3128 Output_data_got
<64, false>* got
3129 = target
->got_section(symtab
, layout
);
3130 got
->add_global_with_rel(gsym
, GOT_TYPE_TLS_OFFSET
,
3131 target
->rela_dyn_section(layout
),
3132 elfcpp::R_X86_64_TPOFF64
);
3134 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
3135 unsupported_reloc_global(object
, r_type
, gsym
);
3138 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
3139 layout
->set_has_static_tls();
3140 if (parameters
->options().shared())
3141 unsupported_reloc_global(object
, r_type
, gsym
);
3150 case elfcpp::R_X86_64_SIZE32
:
3151 case elfcpp::R_X86_64_SIZE64
:
3153 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
3154 object
->name().c_str(), r_type
,
3155 gsym
->demangled_name().c_str());
3162 Target_x86_64
<size
>::gc_process_relocs(Symbol_table
* symtab
,
3164 Sized_relobj_file
<size
, false>* object
,
3165 unsigned int data_shndx
,
3166 unsigned int sh_type
,
3167 const unsigned char* prelocs
,
3169 Output_section
* output_section
,
3170 bool needs_special_offset_handling
,
3171 size_t local_symbol_count
,
3172 const unsigned char* plocal_symbols
)
3175 if (sh_type
== elfcpp::SHT_REL
)
3180 gold::gc_process_relocs
<size
, false, Target_x86_64
<size
>, elfcpp::SHT_RELA
,
3181 typename Target_x86_64
<size
>::Scan
,
3182 typename Target_x86_64
<size
>::Relocatable_size_for_reloc
>(
3191 needs_special_offset_handling
,
3196 // Scan relocations for a section.
3200 Target_x86_64
<size
>::scan_relocs(Symbol_table
* symtab
,
3202 Sized_relobj_file
<size
, false>* object
,
3203 unsigned int data_shndx
,
3204 unsigned int sh_type
,
3205 const unsigned char* prelocs
,
3207 Output_section
* output_section
,
3208 bool needs_special_offset_handling
,
3209 size_t local_symbol_count
,
3210 const unsigned char* plocal_symbols
)
3212 if (sh_type
== elfcpp::SHT_REL
)
3214 gold_error(_("%s: unsupported REL reloc section"),
3215 object
->name().c_str());
3219 gold::scan_relocs
<size
, false, Target_x86_64
<size
>, elfcpp::SHT_RELA
,
3220 typename Target_x86_64
<size
>::Scan
>(
3229 needs_special_offset_handling
,
3234 // Finalize the sections.
3238 Target_x86_64
<size
>::do_finalize_sections(
3240 const Input_objects
*,
3241 Symbol_table
* symtab
)
3243 const Reloc_section
* rel_plt
= (this->plt_
== NULL
3245 : this->plt_
->rela_plt());
3246 layout
->add_target_dynamic_tags(false, this->got_plt_
, rel_plt
,
3247 this->rela_dyn_
, true, false);
3249 // Fill in some more dynamic tags.
3250 Output_data_dynamic
* const odyn
= layout
->dynamic_data();
3253 if (this->plt_
!= NULL
3254 && this->plt_
->output_section() != NULL
3255 && this->plt_
->has_tlsdesc_entry())
3257 unsigned int plt_offset
= this->plt_
->get_tlsdesc_plt_offset();
3258 unsigned int got_offset
= this->plt_
->get_tlsdesc_got_offset();
3259 this->got_
->finalize_data_size();
3260 odyn
->add_section_plus_offset(elfcpp::DT_TLSDESC_PLT
,
3261 this->plt_
, plt_offset
);
3262 odyn
->add_section_plus_offset(elfcpp::DT_TLSDESC_GOT
,
3263 this->got_
, got_offset
);
3267 // Emit any relocs we saved in an attempt to avoid generating COPY
3269 if (this->copy_relocs_
.any_saved_relocs())
3270 this->copy_relocs_
.emit(this->rela_dyn_section(layout
));
3272 // Set the size of the _GLOBAL_OFFSET_TABLE_ symbol to the size of
3273 // the .got.plt section.
3274 Symbol
* sym
= this->global_offset_table_
;
3277 uint64_t data_size
= this->got_plt_
->current_data_size();
3278 symtab
->get_sized_symbol
<size
>(sym
)->set_symsize(data_size
);
3281 if (parameters
->doing_static_link()
3282 && (this->plt_
== NULL
|| !this->plt_
->has_irelative_section()))
3284 // If linking statically, make sure that the __rela_iplt symbols
3285 // were defined if necessary, even if we didn't create a PLT.
3286 static const Define_symbol_in_segment syms
[] =
3289 "__rela_iplt_start", // name
3290 elfcpp::PT_LOAD
, // segment_type
3291 elfcpp::PF_W
, // segment_flags_set
3292 elfcpp::PF(0), // segment_flags_clear
3295 elfcpp::STT_NOTYPE
, // type
3296 elfcpp::STB_GLOBAL
, // binding
3297 elfcpp::STV_HIDDEN
, // visibility
3299 Symbol::SEGMENT_START
, // offset_from_base
3303 "__rela_iplt_end", // name
3304 elfcpp::PT_LOAD
, // segment_type
3305 elfcpp::PF_W
, // segment_flags_set
3306 elfcpp::PF(0), // segment_flags_clear
3309 elfcpp::STT_NOTYPE
, // type
3310 elfcpp::STB_GLOBAL
, // binding
3311 elfcpp::STV_HIDDEN
, // visibility
3313 Symbol::SEGMENT_START
, // offset_from_base
3318 symtab
->define_symbols(layout
, 2, syms
,
3319 layout
->script_options()->saw_sections_clause());
3323 // Perform a relocation.
3327 Target_x86_64
<size
>::Relocate::relocate(
3328 const Relocate_info
<size
, false>* relinfo
,
3329 Target_x86_64
<size
>* target
,
3332 const elfcpp::Rela
<size
, false>& rela
,
3333 unsigned int r_type
,
3334 const Sized_symbol
<size
>* gsym
,
3335 const Symbol_value
<size
>* psymval
,
3336 unsigned char* view
,
3337 typename
elfcpp::Elf_types
<size
>::Elf_Addr address
,
3338 section_size_type view_size
)
3340 if (this->skip_call_tls_get_addr_
)
3342 if ((r_type
!= elfcpp::R_X86_64_PLT32
3343 && r_type
!= elfcpp::R_X86_64_PLT32_BND
3344 && r_type
!= elfcpp::R_X86_64_PC32_BND
3345 && r_type
!= elfcpp::R_X86_64_PC32
)
3347 || strcmp(gsym
->name(), "__tls_get_addr") != 0)
3349 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
3350 _("missing expected TLS relocation"));
3354 this->skip_call_tls_get_addr_
= false;
3362 const Sized_relobj_file
<size
, false>* object
= relinfo
->object
;
3364 // Pick the value to use for symbols defined in the PLT.
3365 Symbol_value
<size
> symval
;
3367 && gsym
->use_plt_offset(Scan::get_reference_flags(r_type
)))
3369 symval
.set_output_value(target
->plt_address_for_global(gsym
));
3372 else if (gsym
== NULL
&& psymval
->is_ifunc_symbol())
3374 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(rela
.get_r_info());
3375 if (object
->local_has_plt_offset(r_sym
))
3377 symval
.set_output_value(target
->plt_address_for_local(object
, r_sym
));
3382 const elfcpp::Elf_Xword addend
= rela
.get_r_addend();
3384 // Get the GOT offset if needed.
3385 // The GOT pointer points to the end of the GOT section.
3386 // We need to subtract the size of the GOT section to get
3387 // the actual offset to use in the relocation.
3388 bool have_got_offset
= false;
3389 // Since the actual offset is always negative, we use signed int to
3390 // support 64-bit GOT relocations.
3394 case elfcpp::R_X86_64_GOT32
:
3395 case elfcpp::R_X86_64_GOT64
:
3396 case elfcpp::R_X86_64_GOTPLT64
:
3397 case elfcpp::R_X86_64_GOTPCREL64
:
3400 gold_assert(gsym
->has_got_offset(GOT_TYPE_STANDARD
));
3401 got_offset
= gsym
->got_offset(GOT_TYPE_STANDARD
) - target
->got_size();
3405 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(rela
.get_r_info());
3406 gold_assert(object
->local_has_got_offset(r_sym
, GOT_TYPE_STANDARD
));
3407 got_offset
= (object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
)
3408 - target
->got_size());
3410 have_got_offset
= true;
3419 case elfcpp::R_X86_64_NONE
:
3420 case elfcpp::R_X86_64_GNU_VTINHERIT
:
3421 case elfcpp::R_X86_64_GNU_VTENTRY
:
3424 case elfcpp::R_X86_64_64
:
3425 Relocate_functions
<size
, false>::rela64(view
, object
, psymval
, addend
);
3428 case elfcpp::R_X86_64_PC64
:
3429 Relocate_functions
<size
, false>::pcrela64(view
, object
, psymval
, addend
,
3433 case elfcpp::R_X86_64_32
:
3434 // FIXME: we need to verify that value + addend fits into 32 bits:
3435 // uint64_t x = value + addend;
3436 // x == static_cast<uint64_t>(static_cast<uint32_t>(x))
3437 // Likewise for other <=32-bit relocations (but see R_X86_64_32S).
3438 Relocate_functions
<size
, false>::rela32(view
, object
, psymval
, addend
);
3441 case elfcpp::R_X86_64_32S
:
3442 // FIXME: we need to verify that value + addend fits into 32 bits:
3443 // int64_t x = value + addend; // note this quantity is signed!
3444 // x == static_cast<int64_t>(static_cast<int32_t>(x))
3445 Relocate_functions
<size
, false>::rela32(view
, object
, psymval
, addend
);
3448 case elfcpp::R_X86_64_PC32
:
3449 case elfcpp::R_X86_64_PC32_BND
:
3450 Relocate_functions
<size
, false>::pcrela32(view
, object
, psymval
, addend
,
3454 case elfcpp::R_X86_64_16
:
3455 Relocate_functions
<size
, false>::rela16(view
, object
, psymval
, addend
);
3458 case elfcpp::R_X86_64_PC16
:
3459 Relocate_functions
<size
, false>::pcrela16(view
, object
, psymval
, addend
,
3463 case elfcpp::R_X86_64_8
:
3464 Relocate_functions
<size
, false>::rela8(view
, object
, psymval
, addend
);
3467 case elfcpp::R_X86_64_PC8
:
3468 Relocate_functions
<size
, false>::pcrela8(view
, object
, psymval
, addend
,
3472 case elfcpp::R_X86_64_PLT32
:
3473 case elfcpp::R_X86_64_PLT32_BND
:
3474 gold_assert(gsym
== NULL
3475 || gsym
->has_plt_offset()
3476 || gsym
->final_value_is_known()
3477 || (gsym
->is_defined()
3478 && !gsym
->is_from_dynobj()
3479 && !gsym
->is_preemptible()));
3480 // Note: while this code looks the same as for R_X86_64_PC32, it
3481 // behaves differently because psymval was set to point to
3482 // the PLT entry, rather than the symbol, in Scan::global().
3483 Relocate_functions
<size
, false>::pcrela32(view
, object
, psymval
, addend
,
3487 case elfcpp::R_X86_64_PLTOFF64
:
3490 gold_assert(gsym
->has_plt_offset()
3491 || gsym
->final_value_is_known());
3492 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
;
3493 // This is the address of GLOBAL_OFFSET_TABLE.
3494 got_address
= target
->got_plt_section()->address();
3495 Relocate_functions
<size
, false>::rela64(view
, object
, psymval
,
3496 addend
- got_address
);
3500 case elfcpp::R_X86_64_GOT32
:
3501 gold_assert(have_got_offset
);
3502 Relocate_functions
<size
, false>::rela32(view
, got_offset
, addend
);
3505 case elfcpp::R_X86_64_GOTPC32
:
3508 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
;
3509 value
= target
->got_plt_section()->address();
3510 Relocate_functions
<size
, false>::pcrela32(view
, value
, addend
, address
);
3514 case elfcpp::R_X86_64_GOT64
:
3515 case elfcpp::R_X86_64_GOTPLT64
:
3516 // R_X86_64_GOTPLT64 is obsolete and treated the the same as
3518 gold_assert(have_got_offset
);
3519 Relocate_functions
<size
, false>::rela64(view
, got_offset
, addend
);
3522 case elfcpp::R_X86_64_GOTPC64
:
3525 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
;
3526 value
= target
->got_plt_section()->address();
3527 Relocate_functions
<size
, false>::pcrela64(view
, value
, addend
, address
);
3531 case elfcpp::R_X86_64_GOTOFF64
:
3533 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
;
3534 value
= (psymval
->value(object
, 0)
3535 - target
->got_plt_section()->address());
3536 Relocate_functions
<size
, false>::rela64(view
, value
, addend
);
3540 case elfcpp::R_X86_64_GOTPCREL
:
3543 // mov foo@GOTPCREL(%rip), %reg
3544 // to lea foo(%rip), %reg.
3546 if (rela
.get_r_offset() >= 2
3548 && ((gsym
== NULL
&& !psymval
->is_ifunc_symbol())
3550 && Target_x86_64
<size
>::can_convert_mov_to_lea(gsym
))))
3553 Relocate_functions
<size
, false>::pcrela32(view
, object
, psymval
, addend
,
3560 gold_assert(gsym
->has_got_offset(GOT_TYPE_STANDARD
));
3561 got_offset
= gsym
->got_offset(GOT_TYPE_STANDARD
) - target
->got_size();
3565 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(rela
.get_r_info());
3566 gold_assert(object
->local_has_got_offset(r_sym
, GOT_TYPE_STANDARD
));
3567 got_offset
= (object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
)
3568 - target
->got_size());
3570 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
;
3571 value
= target
->got_plt_section()->address() + got_offset
;
3572 Relocate_functions
<size
, false>::pcrela32(view
, value
, addend
, address
);
3577 case elfcpp::R_X86_64_GOTPCREL64
:
3579 gold_assert(have_got_offset
);
3580 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
;
3581 value
= target
->got_plt_section()->address() + got_offset
;
3582 Relocate_functions
<size
, false>::pcrela64(view
, value
, addend
, address
);
3586 case elfcpp::R_X86_64_COPY
:
3587 case elfcpp::R_X86_64_GLOB_DAT
:
3588 case elfcpp::R_X86_64_JUMP_SLOT
:
3589 case elfcpp::R_X86_64_RELATIVE
:
3590 case elfcpp::R_X86_64_IRELATIVE
:
3591 // These are outstanding tls relocs, which are unexpected when linking
3592 case elfcpp::R_X86_64_TPOFF64
:
3593 case elfcpp::R_X86_64_DTPMOD64
:
3594 case elfcpp::R_X86_64_TLSDESC
:
3595 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
3596 _("unexpected reloc %u in object file"),
3600 // These are initial tls relocs, which are expected when linking
3601 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
3602 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
3603 case elfcpp::R_X86_64_TLSDESC_CALL
:
3604 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
3605 case elfcpp::R_X86_64_DTPOFF32
:
3606 case elfcpp::R_X86_64_DTPOFF64
:
3607 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
3608 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
3609 this->relocate_tls(relinfo
, target
, relnum
, rela
, r_type
, gsym
, psymval
,
3610 view
, address
, view_size
);
3613 case elfcpp::R_X86_64_SIZE32
:
3614 case elfcpp::R_X86_64_SIZE64
:
3616 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
3617 _("unsupported reloc %u"),
3625 // Perform a TLS relocation.
3629 Target_x86_64
<size
>::Relocate::relocate_tls(
3630 const Relocate_info
<size
, false>* relinfo
,
3631 Target_x86_64
<size
>* target
,
3633 const elfcpp::Rela
<size
, false>& rela
,
3634 unsigned int r_type
,
3635 const Sized_symbol
<size
>* gsym
,
3636 const Symbol_value
<size
>* psymval
,
3637 unsigned char* view
,
3638 typename
elfcpp::Elf_types
<size
>::Elf_Addr address
,
3639 section_size_type view_size
)
3641 Output_segment
* tls_segment
= relinfo
->layout
->tls_segment();
3643 const Sized_relobj_file
<size
, false>* object
= relinfo
->object
;
3644 const elfcpp::Elf_Xword addend
= rela
.get_r_addend();
3645 elfcpp::Shdr
<size
, false> data_shdr(relinfo
->data_shdr
);
3646 bool is_executable
= (data_shdr
.get_sh_flags() & elfcpp::SHF_EXECINSTR
) != 0;
3648 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
= psymval
->value(relinfo
->object
, 0);
3650 const bool is_final
= (gsym
== NULL
3651 ? !parameters
->options().shared()
3652 : gsym
->final_value_is_known());
3653 tls::Tls_optimization optimized_type
3654 = Target_x86_64
<size
>::optimize_tls_reloc(is_final
, r_type
);
3657 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
3658 if (!is_executable
&& optimized_type
== tls::TLSOPT_TO_LE
)
3660 // If this code sequence is used in a non-executable section,
3661 // we will not optimize the R_X86_64_DTPOFF32/64 relocation,
3662 // on the assumption that it's being used by itself in a debug
3663 // section. Therefore, in the unlikely event that the code
3664 // sequence appears in a non-executable section, we simply
3665 // leave it unoptimized.
3666 optimized_type
= tls::TLSOPT_NONE
;
3668 if (optimized_type
== tls::TLSOPT_TO_LE
)
3670 if (tls_segment
== NULL
)
3672 gold_assert(parameters
->errors()->error_count() > 0
3673 || issue_undefined_symbol_error(gsym
));
3676 this->tls_gd_to_le(relinfo
, relnum
, tls_segment
,
3677 rela
, r_type
, value
, view
,
3683 unsigned int got_type
= (optimized_type
== tls::TLSOPT_TO_IE
3684 ? GOT_TYPE_TLS_OFFSET
3685 : GOT_TYPE_TLS_PAIR
);
3686 unsigned int got_offset
;
3689 gold_assert(gsym
->has_got_offset(got_type
));
3690 got_offset
= gsym
->got_offset(got_type
) - target
->got_size();
3694 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(rela
.get_r_info());
3695 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
3696 got_offset
= (object
->local_got_offset(r_sym
, got_type
)
3697 - target
->got_size());
3699 if (optimized_type
== tls::TLSOPT_TO_IE
)
3701 value
= target
->got_plt_section()->address() + got_offset
;
3702 this->tls_gd_to_ie(relinfo
, relnum
, tls_segment
, rela
, r_type
,
3703 value
, view
, address
, view_size
);
3706 else if (optimized_type
== tls::TLSOPT_NONE
)
3708 // Relocate the field with the offset of the pair of GOT
3710 value
= target
->got_plt_section()->address() + got_offset
;
3711 Relocate_functions
<size
, false>::pcrela32(view
, value
, addend
,
3716 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
3717 _("unsupported reloc %u"), r_type
);
3720 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
3721 case elfcpp::R_X86_64_TLSDESC_CALL
:
3722 if (!is_executable
&& optimized_type
== tls::TLSOPT_TO_LE
)
3724 // See above comment for R_X86_64_TLSGD.
3725 optimized_type
= tls::TLSOPT_NONE
;
3727 if (optimized_type
== tls::TLSOPT_TO_LE
)
3729 if (tls_segment
== NULL
)
3731 gold_assert(parameters
->errors()->error_count() > 0
3732 || issue_undefined_symbol_error(gsym
));
3735 this->tls_desc_gd_to_le(relinfo
, relnum
, tls_segment
,
3736 rela
, r_type
, value
, view
,
3742 unsigned int got_type
= (optimized_type
== tls::TLSOPT_TO_IE
3743 ? GOT_TYPE_TLS_OFFSET
3744 : GOT_TYPE_TLS_DESC
);
3745 unsigned int got_offset
= 0;
3746 if (r_type
== elfcpp::R_X86_64_GOTPC32_TLSDESC
3747 && optimized_type
== tls::TLSOPT_NONE
)
3749 // We created GOT entries in the .got.tlsdesc portion of
3750 // the .got.plt section, but the offset stored in the
3751 // symbol is the offset within .got.tlsdesc.
3752 got_offset
= (target
->got_size()
3753 + target
->got_plt_section()->data_size());
3757 gold_assert(gsym
->has_got_offset(got_type
));
3758 got_offset
+= gsym
->got_offset(got_type
) - target
->got_size();
3762 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(rela
.get_r_info());
3763 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
3764 got_offset
+= (object
->local_got_offset(r_sym
, got_type
)
3765 - target
->got_size());
3767 if (optimized_type
== tls::TLSOPT_TO_IE
)
3769 if (tls_segment
== NULL
)
3771 gold_assert(parameters
->errors()->error_count() > 0
3772 || issue_undefined_symbol_error(gsym
));
3775 value
= target
->got_plt_section()->address() + got_offset
;
3776 this->tls_desc_gd_to_ie(relinfo
, relnum
, tls_segment
,
3777 rela
, r_type
, value
, view
, address
,
3781 else if (optimized_type
== tls::TLSOPT_NONE
)
3783 if (r_type
== elfcpp::R_X86_64_GOTPC32_TLSDESC
)
3785 // Relocate the field with the offset of the pair of GOT
3787 value
= target
->got_plt_section()->address() + got_offset
;
3788 Relocate_functions
<size
, false>::pcrela32(view
, value
, addend
,
3794 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
3795 _("unsupported reloc %u"), r_type
);
3798 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
3799 if (!is_executable
&& optimized_type
== tls::TLSOPT_TO_LE
)
3801 // See above comment for R_X86_64_TLSGD.
3802 optimized_type
= tls::TLSOPT_NONE
;
3804 if (optimized_type
== tls::TLSOPT_TO_LE
)
3806 if (tls_segment
== NULL
)
3808 gold_assert(parameters
->errors()->error_count() > 0
3809 || issue_undefined_symbol_error(gsym
));
3812 this->tls_ld_to_le(relinfo
, relnum
, tls_segment
, rela
, r_type
,
3813 value
, view
, view_size
);
3816 else if (optimized_type
== tls::TLSOPT_NONE
)
3818 // Relocate the field with the offset of the GOT entry for
3819 // the module index.
3820 unsigned int got_offset
;
3821 got_offset
= (target
->got_mod_index_entry(NULL
, NULL
, NULL
)
3822 - target
->got_size());
3823 value
= target
->got_plt_section()->address() + got_offset
;
3824 Relocate_functions
<size
, false>::pcrela32(view
, value
, addend
,
3828 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
3829 _("unsupported reloc %u"), r_type
);
3832 case elfcpp::R_X86_64_DTPOFF32
:
3833 // This relocation type is used in debugging information.
3834 // In that case we need to not optimize the value. If the
3835 // section is not executable, then we assume we should not
3836 // optimize this reloc. See comments above for R_X86_64_TLSGD,
3837 // R_X86_64_GOTPC32_TLSDESC, R_X86_64_TLSDESC_CALL, and
3839 if (optimized_type
== tls::TLSOPT_TO_LE
&& is_executable
)
3841 if (tls_segment
== NULL
)
3843 gold_assert(parameters
->errors()->error_count() > 0
3844 || issue_undefined_symbol_error(gsym
));
3847 value
-= tls_segment
->memsz();
3849 Relocate_functions
<size
, false>::rela32(view
, value
, addend
);
3852 case elfcpp::R_X86_64_DTPOFF64
:
3853 // See R_X86_64_DTPOFF32, just above, for why we check for is_executable.
3854 if (optimized_type
== tls::TLSOPT_TO_LE
&& is_executable
)
3856 if (tls_segment
== NULL
)
3858 gold_assert(parameters
->errors()->error_count() > 0
3859 || issue_undefined_symbol_error(gsym
));
3862 value
-= tls_segment
->memsz();
3864 Relocate_functions
<size
, false>::rela64(view
, value
, addend
);
3867 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
3869 && gsym
->is_undefined()
3870 && parameters
->options().output_is_executable())
3872 Target_x86_64
<size
>::Relocate::tls_ie_to_le(relinfo
, relnum
,
3874 r_type
, value
, view
,
3878 else if (optimized_type
== tls::TLSOPT_TO_LE
)
3880 if (tls_segment
== NULL
)
3882 gold_assert(parameters
->errors()->error_count() > 0
3883 || issue_undefined_symbol_error(gsym
));
3886 Target_x86_64
<size
>::Relocate::tls_ie_to_le(relinfo
, relnum
,
3888 r_type
, value
, view
,
3892 else if (optimized_type
== tls::TLSOPT_NONE
)
3894 // Relocate the field with the offset of the GOT entry for
3895 // the tp-relative offset of the symbol.
3896 unsigned int got_offset
;
3899 gold_assert(gsym
->has_got_offset(GOT_TYPE_TLS_OFFSET
));
3900 got_offset
= (gsym
->got_offset(GOT_TYPE_TLS_OFFSET
)
3901 - target
->got_size());
3905 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(rela
.get_r_info());
3906 gold_assert(object
->local_has_got_offset(r_sym
,
3907 GOT_TYPE_TLS_OFFSET
));
3908 got_offset
= (object
->local_got_offset(r_sym
, GOT_TYPE_TLS_OFFSET
)
3909 - target
->got_size());
3911 value
= target
->got_plt_section()->address() + got_offset
;
3912 Relocate_functions
<size
, false>::pcrela32(view
, value
, addend
,
3916 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
3917 _("unsupported reloc type %u"),
3921 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
3922 if (tls_segment
== NULL
)
3924 gold_assert(parameters
->errors()->error_count() > 0
3925 || issue_undefined_symbol_error(gsym
));
3928 value
-= tls_segment
->memsz();
3929 Relocate_functions
<size
, false>::rela32(view
, value
, addend
);
3934 // Do a relocation in which we convert a TLS General-Dynamic to an
3939 Target_x86_64
<size
>::Relocate::tls_gd_to_ie(
3940 const Relocate_info
<size
, false>* relinfo
,
3943 const elfcpp::Rela
<size
, false>& rela
,
3945 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
3946 unsigned char* view
,
3947 typename
elfcpp::Elf_types
<size
>::Elf_Addr address
,
3948 section_size_type view_size
)
3951 // .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
3952 // .word 0x6666; rex64; call __tls_get_addr
3953 // ==> movq %fs:0,%rax; addq x@gottpoff(%rip),%rax
3955 // leaq foo@tlsgd(%rip),%rdi;
3956 // .word 0x6666; rex64; call __tls_get_addr
3957 // ==> movl %fs:0,%eax; addq x@gottpoff(%rip),%rax
3959 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 12);
3960 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
3961 (memcmp(view
+ 4, "\x66\x66\x48\xe8", 4) == 0));
3965 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
,
3967 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
3968 (memcmp(view
- 4, "\x66\x48\x8d\x3d", 4) == 0));
3969 memcpy(view
- 4, "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x03\x05\0\0\0\0",
3974 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
,
3976 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
3977 (memcmp(view
- 3, "\x48\x8d\x3d", 3) == 0));
3978 memcpy(view
- 3, "\x64\x8b\x04\x25\0\0\0\0\x48\x03\x05\0\0\0\0",
3982 const elfcpp::Elf_Xword addend
= rela
.get_r_addend();
3983 Relocate_functions
<size
, false>::pcrela32(view
+ 8, value
, addend
- 8,
3986 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3988 this->skip_call_tls_get_addr_
= true;
3991 // Do a relocation in which we convert a TLS General-Dynamic to a
3996 Target_x86_64
<size
>::Relocate::tls_gd_to_le(
3997 const Relocate_info
<size
, false>* relinfo
,
3999 Output_segment
* tls_segment
,
4000 const elfcpp::Rela
<size
, false>& rela
,
4002 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
4003 unsigned char* view
,
4004 section_size_type view_size
)
4007 // .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
4008 // .word 0x6666; rex64; call __tls_get_addr
4009 // ==> movq %fs:0,%rax; leaq x@tpoff(%rax),%rax
4011 // leaq foo@tlsgd(%rip),%rdi;
4012 // .word 0x6666; rex64; call __tls_get_addr
4013 // ==> movl %fs:0,%eax; leaq x@tpoff(%rax),%rax
4015 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 12);
4016 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
4017 (memcmp(view
+ 4, "\x66\x66\x48\xe8", 4) == 0));
4021 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
,
4023 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
4024 (memcmp(view
- 4, "\x66\x48\x8d\x3d", 4) == 0));
4025 memcpy(view
- 4, "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0\0",
4030 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
,
4032 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
4033 (memcmp(view
- 3, "\x48\x8d\x3d", 3) == 0));
4035 memcpy(view
- 3, "\x64\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0\0",
4039 value
-= tls_segment
->memsz();
4040 Relocate_functions
<size
, false>::rela32(view
+ 8, value
, 0);
4042 // The next reloc should be a PLT32 reloc against __tls_get_addr.
4044 this->skip_call_tls_get_addr_
= true;
4047 // Do a TLSDESC-style General-Dynamic to Initial-Exec transition.
4051 Target_x86_64
<size
>::Relocate::tls_desc_gd_to_ie(
4052 const Relocate_info
<size
, false>* relinfo
,
4055 const elfcpp::Rela
<size
, false>& rela
,
4056 unsigned int r_type
,
4057 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
4058 unsigned char* view
,
4059 typename
elfcpp::Elf_types
<size
>::Elf_Addr address
,
4060 section_size_type view_size
)
4062 if (r_type
== elfcpp::R_X86_64_GOTPC32_TLSDESC
)
4064 // leaq foo@tlsdesc(%rip), %rax
4065 // ==> movq foo@gottpoff(%rip), %rax
4066 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -3);
4067 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 4);
4068 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
4069 view
[-3] == 0x48 && view
[-2] == 0x8d && view
[-1] == 0x05);
4071 const elfcpp::Elf_Xword addend
= rela
.get_r_addend();
4072 Relocate_functions
<size
, false>::pcrela32(view
, value
, addend
, address
);
4076 // call *foo@tlscall(%rax)
4078 gold_assert(r_type
== elfcpp::R_X86_64_TLSDESC_CALL
);
4079 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 2);
4080 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
4081 view
[0] == 0xff && view
[1] == 0x10);
4087 // Do a TLSDESC-style General-Dynamic to Local-Exec transition.
4091 Target_x86_64
<size
>::Relocate::tls_desc_gd_to_le(
4092 const Relocate_info
<size
, false>* relinfo
,
4094 Output_segment
* tls_segment
,
4095 const elfcpp::Rela
<size
, false>& rela
,
4096 unsigned int r_type
,
4097 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
4098 unsigned char* view
,
4099 section_size_type view_size
)
4101 if (r_type
== elfcpp::R_X86_64_GOTPC32_TLSDESC
)
4103 // leaq foo@tlsdesc(%rip), %rax
4104 // ==> movq foo@tpoff, %rax
4105 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -3);
4106 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 4);
4107 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
4108 view
[-3] == 0x48 && view
[-2] == 0x8d && view
[-1] == 0x05);
4111 value
-= tls_segment
->memsz();
4112 Relocate_functions
<size
, false>::rela32(view
, value
, 0);
4116 // call *foo@tlscall(%rax)
4118 gold_assert(r_type
== elfcpp::R_X86_64_TLSDESC_CALL
);
4119 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 2);
4120 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
4121 view
[0] == 0xff && view
[1] == 0x10);
4129 Target_x86_64
<size
>::Relocate::tls_ld_to_le(
4130 const Relocate_info
<size
, false>* relinfo
,
4133 const elfcpp::Rela
<size
, false>& rela
,
4135 typename
elfcpp::Elf_types
<size
>::Elf_Addr
,
4136 unsigned char* view
,
4137 section_size_type view_size
)
4139 // leaq foo@tlsld(%rip),%rdi; call __tls_get_addr@plt;
4141 // ... leq foo@dtpoff(%rax),%reg
4142 // ==> .word 0x6666; .byte 0x66; movq %fs:0,%rax ... leaq x@tpoff(%rax),%rdx
4144 // ... leq foo@dtpoff(%rax),%reg
4145 // ==> nopl 0x0(%rax); movl %fs:0,%eax ... leaq x@tpoff(%rax),%rdx
4147 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -3);
4148 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 9);
4150 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
4151 view
[-3] == 0x48 && view
[-2] == 0x8d && view
[-1] == 0x3d);
4153 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(), view
[4] == 0xe8);
4156 memcpy(view
- 3, "\x66\x66\x66\x64\x48\x8b\x04\x25\0\0\0\0", 12);
4158 memcpy(view
- 3, "\x0f\x1f\x40\x00\x64\x8b\x04\x25\0\0\0\0", 12);
4160 // The next reloc should be a PLT32 reloc against __tls_get_addr.
4162 this->skip_call_tls_get_addr_
= true;
4165 // Do a relocation in which we convert a TLS Initial-Exec to a
4170 Target_x86_64
<size
>::Relocate::tls_ie_to_le(
4171 const Relocate_info
<size
, false>* relinfo
,
4173 Output_segment
* tls_segment
,
4174 const elfcpp::Rela
<size
, false>& rela
,
4176 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
4177 unsigned char* view
,
4178 section_size_type view_size
)
4180 // We need to examine the opcodes to figure out which instruction we
4183 // movq foo@gottpoff(%rip),%reg ==> movq $YY,%reg
4184 // addq foo@gottpoff(%rip),%reg ==> addq $YY,%reg
4186 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -3);
4187 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 4);
4189 unsigned char op1
= view
[-3];
4190 unsigned char op2
= view
[-2];
4191 unsigned char op3
= view
[-1];
4192 unsigned char reg
= op3
>> 3;
4199 else if (size
== 32 && op1
== 0x44)
4202 view
[-1] = 0xc0 | reg
;
4206 // Special handling for %rsp.
4209 else if (size
== 32 && op1
== 0x44)
4212 view
[-1] = 0xc0 | reg
;
4219 else if (size
== 32 && op1
== 0x44)
4222 view
[-1] = 0x80 | reg
| (reg
<< 3);
4225 if (tls_segment
!= NULL
)
4226 value
-= tls_segment
->memsz();
4227 Relocate_functions
<size
, false>::rela32(view
, value
, 0);
4230 // Relocate section data.
4234 Target_x86_64
<size
>::relocate_section(
4235 const Relocate_info
<size
, false>* relinfo
,
4236 unsigned int sh_type
,
4237 const unsigned char* prelocs
,
4239 Output_section
* output_section
,
4240 bool needs_special_offset_handling
,
4241 unsigned char* view
,
4242 typename
elfcpp::Elf_types
<size
>::Elf_Addr address
,
4243 section_size_type view_size
,
4244 const Reloc_symbol_changes
* reloc_symbol_changes
)
4246 gold_assert(sh_type
== elfcpp::SHT_RELA
);
4248 gold::relocate_section
<size
, false, Target_x86_64
<size
>, elfcpp::SHT_RELA
,
4249 typename Target_x86_64
<size
>::Relocate
,
4250 gold::Default_comdat_behavior
>(
4256 needs_special_offset_handling
,
4260 reloc_symbol_changes
);
4263 // Apply an incremental relocation. Incremental relocations always refer
4264 // to global symbols.
4268 Target_x86_64
<size
>::apply_relocation(
4269 const Relocate_info
<size
, false>* relinfo
,
4270 typename
elfcpp::Elf_types
<size
>::Elf_Addr r_offset
,
4271 unsigned int r_type
,
4272 typename
elfcpp::Elf_types
<size
>::Elf_Swxword r_addend
,
4274 unsigned char* view
,
4275 typename
elfcpp::Elf_types
<size
>::Elf_Addr address
,
4276 section_size_type view_size
)
4278 gold::apply_relocation
<size
, false, Target_x86_64
<size
>,
4279 typename Target_x86_64
<size
>::Relocate
>(
4291 // Return the size of a relocation while scanning during a relocatable
4296 Target_x86_64
<size
>::Relocatable_size_for_reloc::get_size_for_reloc(
4297 unsigned int r_type
,
4302 case elfcpp::R_X86_64_NONE
:
4303 case elfcpp::R_X86_64_GNU_VTINHERIT
:
4304 case elfcpp::R_X86_64_GNU_VTENTRY
:
4305 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
4306 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
4307 case elfcpp::R_X86_64_TLSDESC_CALL
:
4308 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
4309 case elfcpp::R_X86_64_DTPOFF32
:
4310 case elfcpp::R_X86_64_DTPOFF64
:
4311 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
4312 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
4315 case elfcpp::R_X86_64_64
:
4316 case elfcpp::R_X86_64_PC64
:
4317 case elfcpp::R_X86_64_GOTOFF64
:
4318 case elfcpp::R_X86_64_GOTPC64
:
4319 case elfcpp::R_X86_64_PLTOFF64
:
4320 case elfcpp::R_X86_64_GOT64
:
4321 case elfcpp::R_X86_64_GOTPCREL64
:
4322 case elfcpp::R_X86_64_GOTPCREL
:
4323 case elfcpp::R_X86_64_GOTPLT64
:
4326 case elfcpp::R_X86_64_32
:
4327 case elfcpp::R_X86_64_32S
:
4328 case elfcpp::R_X86_64_PC32
:
4329 case elfcpp::R_X86_64_PC32_BND
:
4330 case elfcpp::R_X86_64_PLT32
:
4331 case elfcpp::R_X86_64_PLT32_BND
:
4332 case elfcpp::R_X86_64_GOTPC32
:
4333 case elfcpp::R_X86_64_GOT32
:
4336 case elfcpp::R_X86_64_16
:
4337 case elfcpp::R_X86_64_PC16
:
4340 case elfcpp::R_X86_64_8
:
4341 case elfcpp::R_X86_64_PC8
:
4344 case elfcpp::R_X86_64_COPY
:
4345 case elfcpp::R_X86_64_GLOB_DAT
:
4346 case elfcpp::R_X86_64_JUMP_SLOT
:
4347 case elfcpp::R_X86_64_RELATIVE
:
4348 case elfcpp::R_X86_64_IRELATIVE
:
4349 // These are outstanding tls relocs, which are unexpected when linking
4350 case elfcpp::R_X86_64_TPOFF64
:
4351 case elfcpp::R_X86_64_DTPMOD64
:
4352 case elfcpp::R_X86_64_TLSDESC
:
4353 object
->error(_("unexpected reloc %u in object file"), r_type
);
4356 case elfcpp::R_X86_64_SIZE32
:
4357 case elfcpp::R_X86_64_SIZE64
:
4359 object
->error(_("unsupported reloc %u against local symbol"), r_type
);
4364 // Scan the relocs during a relocatable link.
4368 Target_x86_64
<size
>::scan_relocatable_relocs(
4369 Symbol_table
* symtab
,
4371 Sized_relobj_file
<size
, false>* object
,
4372 unsigned int data_shndx
,
4373 unsigned int sh_type
,
4374 const unsigned char* prelocs
,
4376 Output_section
* output_section
,
4377 bool needs_special_offset_handling
,
4378 size_t local_symbol_count
,
4379 const unsigned char* plocal_symbols
,
4380 Relocatable_relocs
* rr
)
4382 gold_assert(sh_type
== elfcpp::SHT_RELA
);
4384 typedef gold::Default_scan_relocatable_relocs
<elfcpp::SHT_RELA
,
4385 Relocatable_size_for_reloc
> Scan_relocatable_relocs
;
4387 gold::scan_relocatable_relocs
<size
, false, elfcpp::SHT_RELA
,
4388 Scan_relocatable_relocs
>(
4396 needs_special_offset_handling
,
4402 // Relocate a section during a relocatable link.
4406 Target_x86_64
<size
>::relocate_relocs(
4407 const Relocate_info
<size
, false>* relinfo
,
4408 unsigned int sh_type
,
4409 const unsigned char* prelocs
,
4411 Output_section
* output_section
,
4412 typename
elfcpp::Elf_types
<size
>::Elf_Off offset_in_output_section
,
4413 const Relocatable_relocs
* rr
,
4414 unsigned char* view
,
4415 typename
elfcpp::Elf_types
<size
>::Elf_Addr view_address
,
4416 section_size_type view_size
,
4417 unsigned char* reloc_view
,
4418 section_size_type reloc_view_size
)
4420 gold_assert(sh_type
== elfcpp::SHT_RELA
);
4422 gold::relocate_relocs
<size
, false, elfcpp::SHT_RELA
>(
4427 offset_in_output_section
,
4436 // Return the value to use for a dynamic which requires special
4437 // treatment. This is how we support equality comparisons of function
4438 // pointers across shared library boundaries, as described in the
4439 // processor specific ABI supplement.
4443 Target_x86_64
<size
>::do_dynsym_value(const Symbol
* gsym
) const
4445 gold_assert(gsym
->is_from_dynobj() && gsym
->has_plt_offset());
4446 return this->plt_address_for_global(gsym
);
4449 // Return a string used to fill a code section with nops to take up
4450 // the specified length.
4454 Target_x86_64
<size
>::do_code_fill(section_size_type length
) const
4458 // Build a jmpq instruction to skip over the bytes.
4459 unsigned char jmp
[5];
4461 elfcpp::Swap_unaligned
<32, false>::writeval(jmp
+ 1, length
- 5);
4462 return (std::string(reinterpret_cast<char*>(&jmp
[0]), 5)
4463 + std::string(length
- 5, static_cast<char>(0x90)));
4466 // Nop sequences of various lengths.
4467 const char nop1
[1] = { '\x90' }; // nop
4468 const char nop2
[2] = { '\x66', '\x90' }; // xchg %ax %ax
4469 const char nop3
[3] = { '\x0f', '\x1f', '\x00' }; // nop (%rax)
4470 const char nop4
[4] = { '\x0f', '\x1f', '\x40', // nop 0(%rax)
4472 const char nop5
[5] = { '\x0f', '\x1f', '\x44', // nop 0(%rax,%rax,1)
4474 const char nop6
[6] = { '\x66', '\x0f', '\x1f', // nopw 0(%rax,%rax,1)
4475 '\x44', '\x00', '\x00' };
4476 const char nop7
[7] = { '\x0f', '\x1f', '\x80', // nopl 0L(%rax)
4477 '\x00', '\x00', '\x00',
4479 const char nop8
[8] = { '\x0f', '\x1f', '\x84', // nopl 0L(%rax,%rax,1)
4480 '\x00', '\x00', '\x00',
4482 const char nop9
[9] = { '\x66', '\x0f', '\x1f', // nopw 0L(%rax,%rax,1)
4483 '\x84', '\x00', '\x00',
4484 '\x00', '\x00', '\x00' };
4485 const char nop10
[10] = { '\x66', '\x2e', '\x0f', // nopw %cs:0L(%rax,%rax,1)
4486 '\x1f', '\x84', '\x00',
4487 '\x00', '\x00', '\x00',
4489 const char nop11
[11] = { '\x66', '\x66', '\x2e', // data16
4490 '\x0f', '\x1f', '\x84', // nopw %cs:0L(%rax,%rax,1)
4491 '\x00', '\x00', '\x00',
4493 const char nop12
[12] = { '\x66', '\x66', '\x66', // data16; data16
4494 '\x2e', '\x0f', '\x1f', // nopw %cs:0L(%rax,%rax,1)
4495 '\x84', '\x00', '\x00',
4496 '\x00', '\x00', '\x00' };
4497 const char nop13
[13] = { '\x66', '\x66', '\x66', // data16; data16; data16
4498 '\x66', '\x2e', '\x0f', // nopw %cs:0L(%rax,%rax,1)
4499 '\x1f', '\x84', '\x00',
4500 '\x00', '\x00', '\x00',
4502 const char nop14
[14] = { '\x66', '\x66', '\x66', // data16; data16; data16
4503 '\x66', '\x66', '\x2e', // data16
4504 '\x0f', '\x1f', '\x84', // nopw %cs:0L(%rax,%rax,1)
4505 '\x00', '\x00', '\x00',
4507 const char nop15
[15] = { '\x66', '\x66', '\x66', // data16; data16; data16
4508 '\x66', '\x66', '\x66', // data16; data16
4509 '\x2e', '\x0f', '\x1f', // nopw %cs:0L(%rax,%rax,1)
4510 '\x84', '\x00', '\x00',
4511 '\x00', '\x00', '\x00' };
4513 const char* nops
[16] = {
4515 nop1
, nop2
, nop3
, nop4
, nop5
, nop6
, nop7
,
4516 nop8
, nop9
, nop10
, nop11
, nop12
, nop13
, nop14
, nop15
4519 return std::string(nops
[length
], length
);
4522 // Return the addend to use for a target specific relocation. The
4523 // only target specific relocation is R_X86_64_TLSDESC for a local
4524 // symbol. We want to set the addend is the offset of the local
4525 // symbol in the TLS segment.
4529 Target_x86_64
<size
>::do_reloc_addend(void* arg
, unsigned int r_type
,
4532 gold_assert(r_type
== elfcpp::R_X86_64_TLSDESC
);
4533 uintptr_t intarg
= reinterpret_cast<uintptr_t>(arg
);
4534 gold_assert(intarg
< this->tlsdesc_reloc_info_
.size());
4535 const Tlsdesc_info
& ti(this->tlsdesc_reloc_info_
[intarg
]);
4536 const Symbol_value
<size
>* psymval
= ti
.object
->local_symbol(ti
.r_sym
);
4537 gold_assert(psymval
->is_tls_symbol());
4538 // The value of a TLS symbol is the offset in the TLS segment.
4539 return psymval
->value(ti
.object
, 0);
4542 // Return the value to use for the base of a DW_EH_PE_datarel offset
4543 // in an FDE. Solaris and SVR4 use DW_EH_PE_datarel because their
4544 // assembler can not write out the difference between two labels in
4545 // different sections, so instead of using a pc-relative value they
4546 // use an offset from the GOT.
4550 Target_x86_64
<size
>::do_ehframe_datarel_base() const
4552 gold_assert(this->global_offset_table_
!= NULL
);
4553 Symbol
* sym
= this->global_offset_table_
;
4554 Sized_symbol
<size
>* ssym
= static_cast<Sized_symbol
<size
>*>(sym
);
4555 return ssym
->value();
4558 // FNOFFSET in section SHNDX in OBJECT is the start of a function
4559 // compiled with -fsplit-stack. The function calls non-split-stack
4560 // code. We have to change the function so that it always ensures
4561 // that it has enough stack space to run some random function.
4563 static const unsigned char cmp_insn_32
[] = { 0x64, 0x3b, 0x24, 0x25 };
4564 static const unsigned char lea_r10_insn_32
[] = { 0x44, 0x8d, 0x94, 0x24 };
4565 static const unsigned char lea_r11_insn_32
[] = { 0x44, 0x8d, 0x9c, 0x24 };
4567 static const unsigned char cmp_insn_64
[] = { 0x64, 0x48, 0x3b, 0x24, 0x25 };
4568 static const unsigned char lea_r10_insn_64
[] = { 0x4c, 0x8d, 0x94, 0x24 };
4569 static const unsigned char lea_r11_insn_64
[] = { 0x4c, 0x8d, 0x9c, 0x24 };
4573 Target_x86_64
<size
>::do_calls_non_split(Relobj
* object
, unsigned int shndx
,
4574 section_offset_type fnoffset
,
4575 section_size_type fnsize
,
4576 unsigned char* view
,
4577 section_size_type view_size
,
4579 std::string
* to
) const
4581 const char* const cmp_insn
= reinterpret_cast<const char*>
4582 (size
== 32 ? cmp_insn_32
: cmp_insn_64
);
4583 const char* const lea_r10_insn
= reinterpret_cast<const char*>
4584 (size
== 32 ? lea_r10_insn_32
: lea_r10_insn_64
);
4585 const char* const lea_r11_insn
= reinterpret_cast<const char*>
4586 (size
== 32 ? lea_r11_insn_32
: lea_r11_insn_64
);
4588 const size_t cmp_insn_len
=
4589 (size
== 32 ? sizeof(cmp_insn_32
) : sizeof(cmp_insn_64
));
4590 const size_t lea_r10_insn_len
=
4591 (size
== 32 ? sizeof(lea_r10_insn_32
) : sizeof(lea_r10_insn_64
));
4592 const size_t lea_r11_insn_len
=
4593 (size
== 32 ? sizeof(lea_r11_insn_32
) : sizeof(lea_r11_insn_64
));
4594 const size_t nop_len
= (size
== 32 ? 7 : 8);
4596 // The function starts with a comparison of the stack pointer and a
4597 // field in the TCB. This is followed by a jump.
4600 if (this->match_view(view
, view_size
, fnoffset
, cmp_insn
, cmp_insn_len
)
4601 && fnsize
> nop_len
+ 1)
4603 // We will call __morestack if the carry flag is set after this
4604 // comparison. We turn the comparison into an stc instruction
4606 view
[fnoffset
] = '\xf9';
4607 this->set_view_to_nop(view
, view_size
, fnoffset
+ 1, nop_len
);
4609 // lea NN(%rsp),%r10
4610 // lea NN(%rsp),%r11
4611 else if ((this->match_view(view
, view_size
, fnoffset
,
4612 lea_r10_insn
, lea_r10_insn_len
)
4613 || this->match_view(view
, view_size
, fnoffset
,
4614 lea_r11_insn
, lea_r11_insn_len
))
4617 // This is loading an offset from the stack pointer for a
4618 // comparison. The offset is negative, so we decrease the
4619 // offset by the amount of space we need for the stack. This
4620 // means we will avoid calling __morestack if there happens to
4621 // be plenty of space on the stack already.
4622 unsigned char* pval
= view
+ fnoffset
+ 4;
4623 uint32_t val
= elfcpp::Swap_unaligned
<32, false>::readval(pval
);
4624 val
-= parameters
->options().split_stack_adjust_size();
4625 elfcpp::Swap_unaligned
<32, false>::writeval(pval
, val
);
4629 if (!object
->has_no_split_stack())
4630 object
->error(_("failed to match split-stack sequence at "
4631 "section %u offset %0zx"),
4632 shndx
, static_cast<size_t>(fnoffset
));
4636 // We have to change the function so that it calls
4637 // __morestack_non_split instead of __morestack. The former will
4638 // allocate additional stack space.
4639 *from
= "__morestack";
4640 *to
= "__morestack_non_split";
4643 // The selector for x86_64 object files. Note this is never instantiated
4644 // directly. It's only used in Target_selector_x86_64_nacl, below.
4647 class Target_selector_x86_64
: public Target_selector_freebsd
4650 Target_selector_x86_64()
4651 : Target_selector_freebsd(elfcpp::EM_X86_64
, size
, false,
4653 ? "elf64-x86-64" : "elf32-x86-64"),
4655 ? "elf64-x86-64-freebsd"
4656 : "elf32-x86-64-freebsd"),
4657 (size
== 64 ? "elf_x86_64" : "elf32_x86_64"))
4661 do_instantiate_target()
4662 { return new Target_x86_64
<size
>(); }
4666 // NaCl variant. It uses different PLT contents.
4669 class Output_data_plt_x86_64_nacl
: public Output_data_plt_x86_64
<size
>
4672 Output_data_plt_x86_64_nacl(Layout
* layout
,
4673 Output_data_got
<64, false>* got
,
4674 Output_data_got_plt_x86_64
* got_plt
,
4675 Output_data_space
* got_irelative
)
4676 : Output_data_plt_x86_64
<size
>(layout
, plt_entry_size
,
4677 got
, got_plt
, got_irelative
)
4680 Output_data_plt_x86_64_nacl(Layout
* layout
,
4681 Output_data_got
<64, false>* got
,
4682 Output_data_got_plt_x86_64
* got_plt
,
4683 Output_data_space
* got_irelative
,
4684 unsigned int plt_count
)
4685 : Output_data_plt_x86_64
<size
>(layout
, plt_entry_size
,
4686 got
, got_plt
, got_irelative
,
4691 virtual unsigned int
4692 do_get_plt_entry_size() const
4693 { return plt_entry_size
; }
4696 do_add_eh_frame(Layout
* layout
)
4698 layout
->add_eh_frame_for_plt(this,
4699 this->plt_eh_frame_cie
,
4700 this->plt_eh_frame_cie_size
,
4702 plt_eh_frame_fde_size
);
4706 do_fill_first_plt_entry(unsigned char* pov
,
4707 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_addr
,
4708 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_addr
);
4710 virtual unsigned int
4711 do_fill_plt_entry(unsigned char* pov
,
4712 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
4713 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
4714 unsigned int got_offset
,
4715 unsigned int plt_offset
,
4716 unsigned int plt_index
);
4719 do_fill_tlsdesc_entry(unsigned char* pov
,
4720 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
4721 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
4722 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_base
,
4723 unsigned int tlsdesc_got_offset
,
4724 unsigned int plt_offset
);
4727 // The size of an entry in the PLT.
4728 static const int plt_entry_size
= 64;
4730 // The first entry in the PLT.
4731 static const unsigned char first_plt_entry
[plt_entry_size
];
4733 // Other entries in the PLT for an executable.
4734 static const unsigned char plt_entry
[plt_entry_size
];
4736 // The reserved TLSDESC entry in the PLT for an executable.
4737 static const unsigned char tlsdesc_plt_entry
[plt_entry_size
];
4739 // The .eh_frame unwind information for the PLT.
4740 static const int plt_eh_frame_fde_size
= 32;
4741 static const unsigned char plt_eh_frame_fde
[plt_eh_frame_fde_size
];
4745 class Target_x86_64_nacl
: public Target_x86_64
<size
>
4748 Target_x86_64_nacl()
4749 : Target_x86_64
<size
>(&x86_64_nacl_info
)
4752 virtual Output_data_plt_x86_64
<size
>*
4753 do_make_data_plt(Layout
* layout
,
4754 Output_data_got
<64, false>* got
,
4755 Output_data_got_plt_x86_64
* got_plt
,
4756 Output_data_space
* got_irelative
)
4758 return new Output_data_plt_x86_64_nacl
<size
>(layout
, got
, got_plt
,
4762 virtual Output_data_plt_x86_64
<size
>*
4763 do_make_data_plt(Layout
* layout
,
4764 Output_data_got
<64, false>* got
,
4765 Output_data_got_plt_x86_64
* got_plt
,
4766 Output_data_space
* got_irelative
,
4767 unsigned int plt_count
)
4769 return new Output_data_plt_x86_64_nacl
<size
>(layout
, got
, got_plt
,
4775 do_code_fill(section_size_type length
) const;
4778 static const Target::Target_info x86_64_nacl_info
;
4782 const Target::Target_info Target_x86_64_nacl
<64>::x86_64_nacl_info
=
4785 false, // is_big_endian
4786 elfcpp::EM_X86_64
, // machine_code
4787 false, // has_make_symbol
4788 false, // has_resolve
4789 true, // has_code_fill
4790 true, // is_default_stack_executable
4791 true, // can_icf_inline_merge_sections
4793 "/lib64/ld-nacl-x86-64.so.1", // dynamic_linker
4794 0x20000, // default_text_segment_address
4795 0x10000, // abi_pagesize (overridable by -z max-page-size)
4796 0x10000, // common_pagesize (overridable by -z common-page-size)
4797 true, // isolate_execinstr
4798 0x10000000, // rosegment_gap
4799 elfcpp::SHN_UNDEF
, // small_common_shndx
4800 elfcpp::SHN_X86_64_LCOMMON
, // large_common_shndx
4801 0, // small_common_section_flags
4802 elfcpp::SHF_X86_64_LARGE
, // large_common_section_flags
4803 NULL
, // attributes_section
4804 NULL
, // attributes_vendor
4805 "_start" // entry_symbol_name
4809 const Target::Target_info Target_x86_64_nacl
<32>::x86_64_nacl_info
=
4812 false, // is_big_endian
4813 elfcpp::EM_X86_64
, // machine_code
4814 false, // has_make_symbol
4815 false, // has_resolve
4816 true, // has_code_fill
4817 true, // is_default_stack_executable
4818 true, // can_icf_inline_merge_sections
4820 "/lib/ld-nacl-x86-64.so.1", // dynamic_linker
4821 0x20000, // default_text_segment_address
4822 0x10000, // abi_pagesize (overridable by -z max-page-size)
4823 0x10000, // common_pagesize (overridable by -z common-page-size)
4824 true, // isolate_execinstr
4825 0x10000000, // rosegment_gap
4826 elfcpp::SHN_UNDEF
, // small_common_shndx
4827 elfcpp::SHN_X86_64_LCOMMON
, // large_common_shndx
4828 0, // small_common_section_flags
4829 elfcpp::SHF_X86_64_LARGE
, // large_common_section_flags
4830 NULL
, // attributes_section
4831 NULL
, // attributes_vendor
4832 "_start" // entry_symbol_name
4835 #define NACLMASK 0xe0 // 32-byte alignment mask.
4837 // The first entry in the PLT.
4841 Output_data_plt_x86_64_nacl
<size
>::first_plt_entry
[plt_entry_size
] =
4843 0xff, 0x35, // pushq contents of memory address
4844 0, 0, 0, 0, // replaced with address of .got + 8
4845 0x4c, 0x8b, 0x1d, // mov GOT+16(%rip), %r11
4846 0, 0, 0, 0, // replaced with address of .got + 16
4847 0x41, 0x83, 0xe3, NACLMASK
, // and $-32, %r11d
4848 0x4d, 0x01, 0xfb, // add %r15, %r11
4849 0x41, 0xff, 0xe3, // jmpq *%r11
4851 // 9-byte nop sequence to pad out to the next 32-byte boundary.
4852 0x66, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw 0x0(%rax,%rax,1)
4854 // 32 bytes of nop to pad out to the standard size
4855 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, // excess data32 prefixes
4856 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4857 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, // excess data32 prefixes
4858 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4859 0x66, // excess data32 prefix
4865 Output_data_plt_x86_64_nacl
<size
>::do_fill_first_plt_entry(
4867 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
4868 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
)
4870 memcpy(pov
, first_plt_entry
, plt_entry_size
);
4871 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
4873 - (plt_address
+ 2 + 4)));
4874 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 9,
4876 - (plt_address
+ 9 + 4)));
4879 // Subsequent entries in the PLT.
4883 Output_data_plt_x86_64_nacl
<size
>::plt_entry
[plt_entry_size
] =
4885 0x4c, 0x8b, 0x1d, // mov name@GOTPCREL(%rip),%r11
4886 0, 0, 0, 0, // replaced with address of symbol in .got
4887 0x41, 0x83, 0xe3, NACLMASK
, // and $-32, %r11d
4888 0x4d, 0x01, 0xfb, // add %r15, %r11
4889 0x41, 0xff, 0xe3, // jmpq *%r11
4891 // 15-byte nop sequence to pad out to the next 32-byte boundary.
4892 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, // excess data32 prefixes
4893 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4895 // Lazy GOT entries point here (32-byte aligned).
4896 0x68, // pushq immediate
4897 0, 0, 0, 0, // replaced with index into relocation table
4898 0xe9, // jmp relative
4899 0, 0, 0, 0, // replaced with offset to start of .plt0
4901 // 22 bytes of nop to pad out to the standard size.
4902 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, // excess data32 prefixes
4903 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4904 0x0f, 0x1f, 0x80, 0, 0, 0, 0, // nopl 0x0(%rax)
4909 Output_data_plt_x86_64_nacl
<size
>::do_fill_plt_entry(
4911 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
4912 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
4913 unsigned int got_offset
,
4914 unsigned int plt_offset
,
4915 unsigned int plt_index
)
4917 memcpy(pov
, plt_entry
, plt_entry_size
);
4918 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 3,
4919 (got_address
+ got_offset
4920 - (plt_address
+ plt_offset
4923 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 33, plt_index
);
4924 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 38,
4925 - (plt_offset
+ 38 + 4));
4930 // The reserved TLSDESC entry in the PLT.
4934 Output_data_plt_x86_64_nacl
<size
>::tlsdesc_plt_entry
[plt_entry_size
] =
4936 0xff, 0x35, // pushq x(%rip)
4937 0, 0, 0, 0, // replaced with address of linkmap GOT entry (at PLTGOT + 8)
4938 0x4c, 0x8b, 0x1d, // mov y(%rip),%r11
4939 0, 0, 0, 0, // replaced with offset of reserved TLSDESC_GOT entry
4940 0x41, 0x83, 0xe3, NACLMASK
, // and $-32, %r11d
4941 0x4d, 0x01, 0xfb, // add %r15, %r11
4942 0x41, 0xff, 0xe3, // jmpq *%r11
4944 // 41 bytes of nop to pad out to the standard size.
4945 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, // excess data32 prefixes
4946 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4947 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, // excess data32 prefixes
4948 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4949 0x66, 0x66, // excess data32 prefixes
4950 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4955 Output_data_plt_x86_64_nacl
<size
>::do_fill_tlsdesc_entry(
4957 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
4958 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
4959 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_base
,
4960 unsigned int tlsdesc_got_offset
,
4961 unsigned int plt_offset
)
4963 memcpy(pov
, tlsdesc_plt_entry
, plt_entry_size
);
4964 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
4966 - (plt_address
+ plt_offset
4968 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 9,
4970 + tlsdesc_got_offset
4971 - (plt_address
+ plt_offset
4975 // The .eh_frame unwind information for the PLT.
4979 Output_data_plt_x86_64_nacl
<size
>::plt_eh_frame_fde
[plt_eh_frame_fde_size
] =
4981 0, 0, 0, 0, // Replaced with offset to .plt.
4982 0, 0, 0, 0, // Replaced with size of .plt.
4983 0, // Augmentation size.
4984 elfcpp::DW_CFA_def_cfa_offset
, 16, // DW_CFA_def_cfa_offset: 16.
4985 elfcpp::DW_CFA_advance_loc
+ 6, // Advance 6 to __PLT__ + 6.
4986 elfcpp::DW_CFA_def_cfa_offset
, 24, // DW_CFA_def_cfa_offset: 24.
4987 elfcpp::DW_CFA_advance_loc
+ 58, // Advance 58 to __PLT__ + 64.
4988 elfcpp::DW_CFA_def_cfa_expression
, // DW_CFA_def_cfa_expression.
4989 13, // Block length.
4990 elfcpp::DW_OP_breg7
, 8, // Push %rsp + 8.
4991 elfcpp::DW_OP_breg16
, 0, // Push %rip.
4992 elfcpp::DW_OP_const1u
, 63, // Push 0x3f.
4993 elfcpp::DW_OP_and
, // & (%rip & 0x3f).
4994 elfcpp::DW_OP_const1u
, 37, // Push 0x25.
4995 elfcpp::DW_OP_ge
, // >= ((%rip & 0x3f) >= 0x25)
4996 elfcpp::DW_OP_lit3
, // Push 3.
4997 elfcpp::DW_OP_shl
, // << (((%rip & 0x3f) >= 0x25) << 3)
4998 elfcpp::DW_OP_plus
, // + ((((%rip&0x3f)>=0x25)<<3)+%rsp+8
4999 elfcpp::DW_CFA_nop
, // Align to 32 bytes.
5003 // Return a string used to fill a code section with nops.
5004 // For NaCl, long NOPs are only valid if they do not cross
5005 // bundle alignment boundaries, so keep it simple with one-byte NOPs.
5008 Target_x86_64_nacl
<size
>::do_code_fill(section_size_type length
) const
5010 return std::string(length
, static_cast<char>(0x90));
5013 // The selector for x86_64-nacl object files.
5016 class Target_selector_x86_64_nacl
5017 : public Target_selector_nacl
<Target_selector_x86_64
<size
>,
5018 Target_x86_64_nacl
<size
> >
5021 Target_selector_x86_64_nacl()
5022 : Target_selector_nacl
<Target_selector_x86_64
<size
>,
5023 Target_x86_64_nacl
<size
> >("x86-64",
5025 ? "elf64-x86-64-nacl"
5026 : "elf32-x86-64-nacl",
5029 : "elf32_x86_64_nacl")
5033 Target_selector_x86_64_nacl
<64> target_selector_x86_64
;
5034 Target_selector_x86_64_nacl
<32> target_selector_x32
;
5036 } // End anonymous namespace.