1 // x86_64.cc -- x86_64 target support for gold.
3 // Copyright 2006, 2007, 2008, 2009, 2010, 2011, 2012
4 // Free Software Foundation, Inc.
5 // Written by Ian Lance Taylor <iant@google.com>.
7 // This file is part of gold.
9 // This program is free software; you can redistribute it and/or modify
10 // it under the terms of the GNU General Public License as published by
11 // the Free Software Foundation; either version 3 of the License, or
12 // (at your option) any later version.
14 // This program is distributed in the hope that it will be useful,
15 // but WITHOUT ANY WARRANTY; without even the implied warranty of
16 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 // GNU General Public License for more details.
19 // You should have received a copy of the GNU General Public License
20 // along with this program; if not, write to the Free Software
21 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
22 // MA 02110-1301, USA.
30 #include "parameters.h"
37 #include "copy-relocs.h"
39 #include "target-reloc.h"
40 #include "target-select.h"
52 // A class to handle the PLT data.
53 // This is an abstract base class that handles most of the linker details
54 // but does not know the actual contents of PLT entries. The derived
55 // classes below fill in those details.
58 class Output_data_plt_x86_64
: public Output_section_data
61 typedef Output_data_reloc
<elfcpp::SHT_RELA
, true, size
, false> Reloc_section
;
63 Output_data_plt_x86_64(Layout
* layout
, uint64_t addralign
,
64 Output_data_got
<64, false>* got
,
65 Output_data_space
* got_plt
,
66 Output_data_space
* got_irelative
)
67 : Output_section_data(addralign
), layout_(layout
), tlsdesc_rel_(NULL
),
68 irelative_rel_(NULL
), got_(got
), got_plt_(got_plt
),
69 got_irelative_(got_irelative
), count_(0), irelative_count_(0),
70 tlsdesc_got_offset_(-1U), free_list_()
71 { this->init(layout
); }
73 Output_data_plt_x86_64(Layout
* layout
, uint64_t plt_entry_size
,
74 Output_data_got
<64, false>* got
,
75 Output_data_space
* got_plt
,
76 Output_data_space
* got_irelative
,
77 unsigned int plt_count
)
78 : Output_section_data((plt_count
+ 1) * plt_entry_size
,
79 plt_entry_size
, false),
80 layout_(layout
), tlsdesc_rel_(NULL
), irelative_rel_(NULL
), got_(got
),
81 got_plt_(got_plt
), got_irelative_(got_irelative
), count_(plt_count
),
82 irelative_count_(0), tlsdesc_got_offset_(-1U), free_list_()
86 // Initialize the free list and reserve the first entry.
87 this->free_list_
.init((plt_count
+ 1) * plt_entry_size
, false);
88 this->free_list_
.remove(0, plt_entry_size
);
91 // Initialize the PLT section.
95 // Add an entry to the PLT.
97 add_entry(Symbol_table
*, Layout
*, Symbol
* gsym
);
99 // Add an entry to the PLT for a local STT_GNU_IFUNC symbol.
101 add_local_ifunc_entry(Symbol_table
* symtab
, Layout
*,
102 Sized_relobj_file
<size
, false>* relobj
,
103 unsigned int local_sym_index
);
105 // Add the relocation for a PLT entry.
107 add_relocation(Symbol_table
*, Layout
*, Symbol
* gsym
,
108 unsigned int got_offset
);
110 // Add the reserved TLSDESC_PLT entry to the PLT.
112 reserve_tlsdesc_entry(unsigned int got_offset
)
113 { this->tlsdesc_got_offset_
= got_offset
; }
115 // Return true if a TLSDESC_PLT entry has been reserved.
117 has_tlsdesc_entry() const
118 { return this->tlsdesc_got_offset_
!= -1U; }
120 // Return the GOT offset for the reserved TLSDESC_PLT entry.
122 get_tlsdesc_got_offset() const
123 { return this->tlsdesc_got_offset_
; }
125 // Return the offset of the reserved TLSDESC_PLT entry.
127 get_tlsdesc_plt_offset() const
129 return ((this->count_
+ this->irelative_count_
+ 1)
130 * this->get_plt_entry_size());
133 // Return the .rela.plt section data.
136 { return this->rel_
; }
138 // Return where the TLSDESC relocations should go.
140 rela_tlsdesc(Layout
*);
142 // Return where the IRELATIVE relocations should go in the PLT
145 rela_irelative(Symbol_table
*, Layout
*);
147 // Return whether we created a section for IRELATIVE relocations.
149 has_irelative_section() const
150 { return this->irelative_rel_
!= NULL
; }
152 // Return the number of PLT entries.
155 { return this->count_
+ this->irelative_count_
; }
157 // Return the offset of the first non-reserved PLT entry.
159 first_plt_entry_offset()
160 { return this->get_plt_entry_size(); }
162 // Return the size of a PLT entry.
164 get_plt_entry_size() const
165 { return this->do_get_plt_entry_size(); }
167 // Reserve a slot in the PLT for an existing symbol in an incremental update.
169 reserve_slot(unsigned int plt_index
)
171 this->free_list_
.remove((plt_index
+ 1) * this->get_plt_entry_size(),
172 (plt_index
+ 2) * this->get_plt_entry_size());
175 // Return the PLT address to use for a global symbol.
177 address_for_global(const Symbol
*);
179 // Return the PLT address to use for a local symbol.
181 address_for_local(const Relobj
*, unsigned int symndx
);
183 // Add .eh_frame information for the PLT.
185 add_eh_frame(Layout
* layout
)
186 { this->do_add_eh_frame(layout
); }
189 // Fill in the first PLT entry.
191 fill_first_plt_entry(unsigned char* pov
,
192 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
193 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
)
194 { this->do_fill_first_plt_entry(pov
, got_address
, plt_address
); }
196 // Fill in a normal PLT entry. Returns the offset into the entry that
197 // should be the initial GOT slot value.
199 fill_plt_entry(unsigned char* pov
,
200 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
201 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
202 unsigned int got_offset
,
203 unsigned int plt_offset
,
204 unsigned int plt_index
)
206 return this->do_fill_plt_entry(pov
, got_address
, plt_address
,
207 got_offset
, plt_offset
, plt_index
);
210 // Fill in the reserved TLSDESC PLT entry.
212 fill_tlsdesc_entry(unsigned char* pov
,
213 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
214 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
215 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_base
,
216 unsigned int tlsdesc_got_offset
,
217 unsigned int plt_offset
)
219 this->do_fill_tlsdesc_entry(pov
, got_address
, plt_address
, got_base
,
220 tlsdesc_got_offset
, plt_offset
);
224 do_get_plt_entry_size() const = 0;
227 do_fill_first_plt_entry(unsigned char* pov
,
228 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_addr
,
229 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_addr
)
233 do_fill_plt_entry(unsigned char* pov
,
234 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
235 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
236 unsigned int got_offset
,
237 unsigned int plt_offset
,
238 unsigned int plt_index
) = 0;
241 do_fill_tlsdesc_entry(unsigned char* pov
,
242 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
243 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
244 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_base
,
245 unsigned int tlsdesc_got_offset
,
246 unsigned int plt_offset
) = 0;
249 do_add_eh_frame(Layout
* layout
) = 0;
252 do_adjust_output_section(Output_section
* os
);
254 // Write to a map file.
256 do_print_to_mapfile(Mapfile
* mapfile
) const
257 { mapfile
->print_output_data(this, _("** PLT")); }
259 // The CIE of the .eh_frame unwind information for the PLT.
260 static const int plt_eh_frame_cie_size
= 16;
261 static const unsigned char plt_eh_frame_cie
[plt_eh_frame_cie_size
];
264 // Set the final size.
266 set_final_data_size();
268 // Write out the PLT data.
270 do_write(Output_file
*);
272 // A pointer to the Layout class, so that we can find the .dynamic
273 // section when we write out the GOT PLT section.
275 // The reloc section.
277 // The TLSDESC relocs, if necessary. These must follow the regular
279 Reloc_section
* tlsdesc_rel_
;
280 // The IRELATIVE relocs, if necessary. These must follow the
281 // regular PLT relocations and the TLSDESC relocations.
282 Reloc_section
* irelative_rel_
;
284 Output_data_got
<64, false>* got_
;
285 // The .got.plt section.
286 Output_data_space
* got_plt_
;
287 // The part of the .got.plt section used for IRELATIVE relocs.
288 Output_data_space
* got_irelative_
;
289 // The number of PLT entries.
291 // Number of PLT entries with R_X86_64_IRELATIVE relocs. These
292 // follow the regular PLT entries.
293 unsigned int irelative_count_
;
294 // Offset of the reserved TLSDESC_GOT entry when needed.
295 unsigned int tlsdesc_got_offset_
;
296 // List of available regions within the section, for incremental
298 Free_list free_list_
;
302 class Output_data_plt_x86_64_standard
: public Output_data_plt_x86_64
<size
>
305 Output_data_plt_x86_64_standard(Layout
* layout
,
306 Output_data_got
<64, false>* got
,
307 Output_data_space
* got_plt
,
308 Output_data_space
* got_irelative
)
309 : Output_data_plt_x86_64
<size
>(layout
, plt_entry_size
,
310 got
, got_plt
, got_irelative
)
313 Output_data_plt_x86_64_standard(Layout
* layout
,
314 Output_data_got
<64, false>* got
,
315 Output_data_space
* got_plt
,
316 Output_data_space
* got_irelative
,
317 unsigned int plt_count
)
318 : Output_data_plt_x86_64
<size
>(layout
, plt_entry_size
,
319 got
, got_plt
, got_irelative
,
325 do_get_plt_entry_size() const
326 { return plt_entry_size
; }
329 do_add_eh_frame(Layout
* layout
)
331 layout
->add_eh_frame_for_plt(this,
332 this->plt_eh_frame_cie
,
333 this->plt_eh_frame_cie_size
,
335 plt_eh_frame_fde_size
);
339 do_fill_first_plt_entry(unsigned char* pov
,
340 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_addr
,
341 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_addr
);
344 do_fill_plt_entry(unsigned char* pov
,
345 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
346 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
347 unsigned int got_offset
,
348 unsigned int plt_offset
,
349 unsigned int plt_index
);
352 do_fill_tlsdesc_entry(unsigned char* pov
,
353 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
354 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
355 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_base
,
356 unsigned int tlsdesc_got_offset
,
357 unsigned int plt_offset
);
360 // The size of an entry in the PLT.
361 static const int plt_entry_size
= 16;
363 // The first entry in the PLT.
364 // From the AMD64 ABI: "Unlike Intel386 ABI, this ABI uses the same
365 // procedure linkage table for both programs and shared objects."
366 static const unsigned char first_plt_entry
[plt_entry_size
];
368 // Other entries in the PLT for an executable.
369 static const unsigned char plt_entry
[plt_entry_size
];
371 // The reserved TLSDESC entry in the PLT for an executable.
372 static const unsigned char tlsdesc_plt_entry
[plt_entry_size
];
374 // The .eh_frame unwind information for the PLT.
375 static const int plt_eh_frame_fde_size
= 32;
376 static const unsigned char plt_eh_frame_fde
[plt_eh_frame_fde_size
];
379 // The x86_64 target class.
381 // http://www.x86-64.org/documentation/abi.pdf
382 // TLS info comes from
383 // http://people.redhat.com/drepper/tls.pdf
384 // http://www.lsd.ic.unicamp.br/~oliva/writeups/TLS/RFC-TLSDESC-x86.txt
387 class Target_x86_64
: public Sized_target
<size
, false>
390 // In the x86_64 ABI (p 68), it says "The AMD64 ABI architectures
391 // uses only Elf64_Rela relocation entries with explicit addends."
392 typedef Output_data_reloc
<elfcpp::SHT_RELA
, true, size
, false> Reloc_section
;
394 Target_x86_64(const Target::Target_info
* info
= &x86_64_info
)
395 : Sized_target
<size
, false>(info
),
396 got_(NULL
), plt_(NULL
), got_plt_(NULL
), got_irelative_(NULL
),
397 got_tlsdesc_(NULL
), global_offset_table_(NULL
), rela_dyn_(NULL
),
398 rela_irelative_(NULL
), copy_relocs_(elfcpp::R_X86_64_COPY
),
399 dynbss_(NULL
), got_mod_index_offset_(-1U), tlsdesc_reloc_info_(),
400 tls_base_symbol_defined_(false)
403 // Hook for a new output section.
405 do_new_output_section(Output_section
*) const;
407 // Scan the relocations to look for symbol adjustments.
409 gc_process_relocs(Symbol_table
* symtab
,
411 Sized_relobj_file
<size
, false>* object
,
412 unsigned int data_shndx
,
413 unsigned int sh_type
,
414 const unsigned char* prelocs
,
416 Output_section
* output_section
,
417 bool needs_special_offset_handling
,
418 size_t local_symbol_count
,
419 const unsigned char* plocal_symbols
);
421 // Scan the relocations to look for symbol adjustments.
423 scan_relocs(Symbol_table
* symtab
,
425 Sized_relobj_file
<size
, false>* object
,
426 unsigned int data_shndx
,
427 unsigned int sh_type
,
428 const unsigned char* prelocs
,
430 Output_section
* output_section
,
431 bool needs_special_offset_handling
,
432 size_t local_symbol_count
,
433 const unsigned char* plocal_symbols
);
435 // Finalize the sections.
437 do_finalize_sections(Layout
*, const Input_objects
*, Symbol_table
*);
439 // Return the value to use for a dynamic which requires special
442 do_dynsym_value(const Symbol
*) const;
444 // Relocate a section.
446 relocate_section(const Relocate_info
<size
, false>*,
447 unsigned int sh_type
,
448 const unsigned char* prelocs
,
450 Output_section
* output_section
,
451 bool needs_special_offset_handling
,
453 typename
elfcpp::Elf_types
<size
>::Elf_Addr view_address
,
454 section_size_type view_size
,
455 const Reloc_symbol_changes
*);
457 // Scan the relocs during a relocatable link.
459 scan_relocatable_relocs(Symbol_table
* symtab
,
461 Sized_relobj_file
<size
, false>* object
,
462 unsigned int data_shndx
,
463 unsigned int sh_type
,
464 const unsigned char* prelocs
,
466 Output_section
* output_section
,
467 bool needs_special_offset_handling
,
468 size_t local_symbol_count
,
469 const unsigned char* plocal_symbols
,
470 Relocatable_relocs
*);
472 // Relocate a section during a relocatable link.
474 relocate_for_relocatable(
475 const Relocate_info
<size
, false>*,
476 unsigned int sh_type
,
477 const unsigned char* prelocs
,
479 Output_section
* output_section
,
480 off_t offset_in_output_section
,
481 const Relocatable_relocs
*,
483 typename
elfcpp::Elf_types
<size
>::Elf_Addr view_address
,
484 section_size_type view_size
,
485 unsigned char* reloc_view
,
486 section_size_type reloc_view_size
);
488 // Return a string used to fill a code section with nops.
490 do_code_fill(section_size_type length
) const;
492 // Return whether SYM is defined by the ABI.
494 do_is_defined_by_abi(const Symbol
* sym
) const
495 { return strcmp(sym
->name(), "__tls_get_addr") == 0; }
497 // Return the symbol index to use for a target specific relocation.
498 // The only target specific relocation is R_X86_64_TLSDESC for a
499 // local symbol, which is an absolute reloc.
501 do_reloc_symbol_index(void*, unsigned int r_type
) const
503 gold_assert(r_type
== elfcpp::R_X86_64_TLSDESC
);
507 // Return the addend to use for a target specific relocation.
509 do_reloc_addend(void* arg
, unsigned int r_type
, uint64_t addend
) const;
511 // Return the PLT section.
513 do_plt_address_for_global(const Symbol
* gsym
) const
514 { return this->plt_section()->address_for_global(gsym
); }
517 do_plt_address_for_local(const Relobj
* relobj
, unsigned int symndx
) const
518 { return this->plt_section()->address_for_local(relobj
, symndx
); }
520 // This function should be defined in targets that can use relocation
521 // types to determine (implemented in local_reloc_may_be_function_pointer
522 // and global_reloc_may_be_function_pointer)
523 // if a function's pointer is taken. ICF uses this in safe mode to only
524 // fold those functions whose pointer is defintely not taken. For x86_64
525 // pie binaries, safe ICF cannot be done by looking at relocation types.
527 do_can_check_for_function_pointers() const
528 { return !parameters
->options().pie(); }
530 // Return the base for a DW_EH_PE_datarel encoding.
532 do_ehframe_datarel_base() const;
534 // Adjust -fsplit-stack code which calls non-split-stack code.
536 do_calls_non_split(Relobj
* object
, unsigned int shndx
,
537 section_offset_type fnoffset
, section_size_type fnsize
,
538 unsigned char* view
, section_size_type view_size
,
539 std::string
* from
, std::string
* to
) const;
541 // Return the size of the GOT section.
545 gold_assert(this->got_
!= NULL
);
546 return this->got_
->data_size();
549 // Return the number of entries in the GOT.
551 got_entry_count() const
553 if (this->got_
== NULL
)
555 return this->got_size() / 8;
558 // Return the number of entries in the PLT.
560 plt_entry_count() const;
562 // Return the offset of the first non-reserved PLT entry.
564 first_plt_entry_offset() const;
566 // Return the size of each PLT entry.
568 plt_entry_size() const;
570 // Create the GOT section for an incremental update.
571 Output_data_got_base
*
572 init_got_plt_for_update(Symbol_table
* symtab
,
574 unsigned int got_count
,
575 unsigned int plt_count
);
577 // Reserve a GOT entry for a local symbol, and regenerate any
578 // necessary dynamic relocations.
580 reserve_local_got_entry(unsigned int got_index
,
581 Sized_relobj
<size
, false>* obj
,
583 unsigned int got_type
);
585 // Reserve a GOT entry for a global symbol, and regenerate any
586 // necessary dynamic relocations.
588 reserve_global_got_entry(unsigned int got_index
, Symbol
* gsym
,
589 unsigned int got_type
);
591 // Register an existing PLT entry for a global symbol.
593 register_global_plt_entry(Symbol_table
*, Layout
*, unsigned int plt_index
,
596 // Force a COPY relocation for a given symbol.
598 emit_copy_reloc(Symbol_table
*, Symbol
*, Output_section
*, off_t
);
600 // Apply an incremental relocation.
602 apply_relocation(const Relocate_info
<size
, false>* relinfo
,
603 typename
elfcpp::Elf_types
<size
>::Elf_Addr r_offset
,
605 typename
elfcpp::Elf_types
<size
>::Elf_Swxword r_addend
,
608 typename
elfcpp::Elf_types
<size
>::Elf_Addr address
,
609 section_size_type view_size
);
611 // Add a new reloc argument, returning the index in the vector.
613 add_tlsdesc_info(Sized_relobj_file
<size
, false>* object
, unsigned int r_sym
)
615 this->tlsdesc_reloc_info_
.push_back(Tlsdesc_info(object
, r_sym
));
616 return this->tlsdesc_reloc_info_
.size() - 1;
619 Output_data_plt_x86_64
<size
>*
620 make_data_plt(Layout
* layout
,
621 Output_data_got
<64, false>* got
,
622 Output_data_space
* got_plt
,
623 Output_data_space
* got_irelative
)
625 return this->do_make_data_plt(layout
, got
, got_plt
, got_irelative
);
628 Output_data_plt_x86_64
<size
>*
629 make_data_plt(Layout
* layout
,
630 Output_data_got
<64, false>* got
,
631 Output_data_space
* got_plt
,
632 Output_data_space
* got_irelative
,
633 unsigned int plt_count
)
635 return this->do_make_data_plt(layout
, got
, got_plt
, got_irelative
,
639 virtual Output_data_plt_x86_64
<size
>*
640 do_make_data_plt(Layout
* layout
,
641 Output_data_got
<64, false>* got
,
642 Output_data_space
* got_plt
,
643 Output_data_space
* got_irelative
)
645 return new Output_data_plt_x86_64_standard
<size
>(layout
, got
, got_plt
,
649 virtual Output_data_plt_x86_64
<size
>*
650 do_make_data_plt(Layout
* layout
,
651 Output_data_got
<64, false>* got
,
652 Output_data_space
* got_plt
,
653 Output_data_space
* got_irelative
,
654 unsigned int plt_count
)
656 return new Output_data_plt_x86_64_standard
<size
>(layout
, got
, got_plt
,
662 // The class which scans relocations.
667 : issued_non_pic_error_(false)
671 get_reference_flags(unsigned int r_type
);
674 local(Symbol_table
* symtab
, Layout
* layout
, Target_x86_64
* target
,
675 Sized_relobj_file
<size
, false>* object
,
676 unsigned int data_shndx
,
677 Output_section
* output_section
,
678 const elfcpp::Rela
<size
, false>& reloc
, unsigned int r_type
,
679 const elfcpp::Sym
<size
, false>& lsym
);
682 global(Symbol_table
* symtab
, Layout
* layout
, Target_x86_64
* target
,
683 Sized_relobj_file
<size
, false>* object
,
684 unsigned int data_shndx
,
685 Output_section
* output_section
,
686 const elfcpp::Rela
<size
, false>& reloc
, unsigned int r_type
,
690 local_reloc_may_be_function_pointer(Symbol_table
* symtab
, Layout
* layout
,
691 Target_x86_64
* target
,
692 Sized_relobj_file
<size
, false>* object
,
693 unsigned int data_shndx
,
694 Output_section
* output_section
,
695 const elfcpp::Rela
<size
, false>& reloc
,
697 const elfcpp::Sym
<size
, false>& lsym
);
700 global_reloc_may_be_function_pointer(Symbol_table
* symtab
, Layout
* layout
,
701 Target_x86_64
* target
,
702 Sized_relobj_file
<size
, false>* object
,
703 unsigned int data_shndx
,
704 Output_section
* output_section
,
705 const elfcpp::Rela
<size
, false>& reloc
,
711 unsupported_reloc_local(Sized_relobj_file
<size
, false>*,
712 unsigned int r_type
);
715 unsupported_reloc_global(Sized_relobj_file
<size
, false>*,
716 unsigned int r_type
, Symbol
*);
719 check_non_pic(Relobj
*, unsigned int r_type
, Symbol
*);
722 possible_function_pointer_reloc(unsigned int r_type
);
725 reloc_needs_plt_for_ifunc(Sized_relobj_file
<size
, false>*,
726 unsigned int r_type
);
728 // Whether we have issued an error about a non-PIC compilation.
729 bool issued_non_pic_error_
;
732 // The class which implements relocation.
737 : skip_call_tls_get_addr_(false)
742 if (this->skip_call_tls_get_addr_
)
744 // FIXME: This needs to specify the location somehow.
745 gold_error(_("missing expected TLS relocation"));
749 // Do a relocation. Return false if the caller should not issue
750 // any warnings about this relocation.
752 relocate(const Relocate_info
<size
, false>*, Target_x86_64
*,
754 size_t relnum
, const elfcpp::Rela
<size
, false>&,
755 unsigned int r_type
, const Sized_symbol
<size
>*,
756 const Symbol_value
<size
>*,
757 unsigned char*, typename
elfcpp::Elf_types
<size
>::Elf_Addr
,
761 // Do a TLS relocation.
763 relocate_tls(const Relocate_info
<size
, false>*, Target_x86_64
*,
764 size_t relnum
, const elfcpp::Rela
<size
, false>&,
765 unsigned int r_type
, const Sized_symbol
<size
>*,
766 const Symbol_value
<size
>*,
767 unsigned char*, typename
elfcpp::Elf_types
<size
>::Elf_Addr
,
770 // Do a TLS General-Dynamic to Initial-Exec transition.
772 tls_gd_to_ie(const Relocate_info
<size
, false>*, size_t relnum
,
773 Output_segment
* tls_segment
,
774 const elfcpp::Rela
<size
, false>&, unsigned int r_type
,
775 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
777 typename
elfcpp::Elf_types
<size
>::Elf_Addr
,
778 section_size_type view_size
);
780 // Do a TLS General-Dynamic to Local-Exec transition.
782 tls_gd_to_le(const Relocate_info
<size
, false>*, size_t relnum
,
783 Output_segment
* tls_segment
,
784 const elfcpp::Rela
<size
, false>&, unsigned int r_type
,
785 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
787 section_size_type view_size
);
789 // Do a TLSDESC-style General-Dynamic to Initial-Exec transition.
791 tls_desc_gd_to_ie(const Relocate_info
<size
, false>*, size_t relnum
,
792 Output_segment
* tls_segment
,
793 const elfcpp::Rela
<size
, false>&, unsigned int r_type
,
794 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
796 typename
elfcpp::Elf_types
<size
>::Elf_Addr
,
797 section_size_type view_size
);
799 // Do a TLSDESC-style General-Dynamic to Local-Exec transition.
801 tls_desc_gd_to_le(const Relocate_info
<size
, false>*, size_t relnum
,
802 Output_segment
* tls_segment
,
803 const elfcpp::Rela
<size
, false>&, unsigned int r_type
,
804 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
806 section_size_type view_size
);
808 // Do a TLS Local-Dynamic to Local-Exec transition.
810 tls_ld_to_le(const Relocate_info
<size
, false>*, size_t relnum
,
811 Output_segment
* tls_segment
,
812 const elfcpp::Rela
<size
, false>&, unsigned int r_type
,
813 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
815 section_size_type view_size
);
817 // Do a TLS Initial-Exec to Local-Exec transition.
819 tls_ie_to_le(const Relocate_info
<size
, false>*, size_t relnum
,
820 Output_segment
* tls_segment
,
821 const elfcpp::Rela
<size
, false>&, unsigned int r_type
,
822 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
824 section_size_type view_size
);
826 // This is set if we should skip the next reloc, which should be a
827 // PLT32 reloc against ___tls_get_addr.
828 bool skip_call_tls_get_addr_
;
831 // A class which returns the size required for a relocation type,
832 // used while scanning relocs during a relocatable link.
833 class Relocatable_size_for_reloc
837 get_size_for_reloc(unsigned int, Relobj
*);
840 // Adjust TLS relocation type based on the options and whether this
841 // is a local symbol.
842 static tls::Tls_optimization
843 optimize_tls_reloc(bool is_final
, int r_type
);
845 // Get the GOT section, creating it if necessary.
846 Output_data_got
<64, false>*
847 got_section(Symbol_table
*, Layout
*);
849 // Get the GOT PLT section.
851 got_plt_section() const
853 gold_assert(this->got_plt_
!= NULL
);
854 return this->got_plt_
;
857 // Get the GOT section for TLSDESC entries.
858 Output_data_got
<64, false>*
859 got_tlsdesc_section() const
861 gold_assert(this->got_tlsdesc_
!= NULL
);
862 return this->got_tlsdesc_
;
865 // Create the PLT section.
867 make_plt_section(Symbol_table
* symtab
, Layout
* layout
);
869 // Create a PLT entry for a global symbol.
871 make_plt_entry(Symbol_table
*, Layout
*, Symbol
*);
873 // Create a PLT entry for a local STT_GNU_IFUNC symbol.
875 make_local_ifunc_plt_entry(Symbol_table
*, Layout
*,
876 Sized_relobj_file
<size
, false>* relobj
,
877 unsigned int local_sym_index
);
879 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
881 define_tls_base_symbol(Symbol_table
*, Layout
*);
883 // Create the reserved PLT and GOT entries for the TLS descriptor resolver.
885 reserve_tlsdesc_entries(Symbol_table
* symtab
, Layout
* layout
);
887 // Create a GOT entry for the TLS module index.
889 got_mod_index_entry(Symbol_table
* symtab
, Layout
* layout
,
890 Sized_relobj_file
<size
, false>* object
);
892 // Get the PLT section.
893 Output_data_plt_x86_64
<size
>*
896 gold_assert(this->plt_
!= NULL
);
900 // Get the dynamic reloc section, creating it if necessary.
902 rela_dyn_section(Layout
*);
904 // Get the section to use for TLSDESC relocations.
906 rela_tlsdesc_section(Layout
*) const;
908 // Get the section to use for IRELATIVE relocations.
910 rela_irelative_section(Layout
*);
912 // Add a potential copy relocation.
914 copy_reloc(Symbol_table
* symtab
, Layout
* layout
,
915 Sized_relobj_file
<size
, false>* object
,
916 unsigned int shndx
, Output_section
* output_section
,
917 Symbol
* sym
, const elfcpp::Rela
<size
, false>& reloc
)
919 this->copy_relocs_
.copy_reloc(symtab
, layout
,
920 symtab
->get_sized_symbol
<size
>(sym
),
921 object
, shndx
, output_section
,
922 reloc
, this->rela_dyn_section(layout
));
925 // Information about this specific target which we pass to the
926 // general Target structure.
927 static const Target::Target_info x86_64_info
;
929 // The types of GOT entries needed for this platform.
930 // These values are exposed to the ABI in an incremental link.
931 // Do not renumber existing values without changing the version
932 // number of the .gnu_incremental_inputs section.
935 GOT_TYPE_STANDARD
= 0, // GOT entry for a regular symbol
936 GOT_TYPE_TLS_OFFSET
= 1, // GOT entry for TLS offset
937 GOT_TYPE_TLS_PAIR
= 2, // GOT entry for TLS module/offset pair
938 GOT_TYPE_TLS_DESC
= 3 // GOT entry for TLS_DESC pair
941 // This type is used as the argument to the target specific
942 // relocation routines. The only target specific reloc is
943 // R_X86_64_TLSDESC against a local symbol.
946 Tlsdesc_info(Sized_relobj_file
<size
, false>* a_object
, unsigned int a_r_sym
)
947 : object(a_object
), r_sym(a_r_sym
)
950 // The object in which the local symbol is defined.
951 Sized_relobj_file
<size
, false>* object
;
952 // The local symbol index in the object.
957 Output_data_got
<64, false>* got_
;
959 Output_data_plt_x86_64
<size
>* plt_
;
960 // The GOT PLT section.
961 Output_data_space
* got_plt_
;
962 // The GOT section for IRELATIVE relocations.
963 Output_data_space
* got_irelative_
;
964 // The GOT section for TLSDESC relocations.
965 Output_data_got
<64, false>* got_tlsdesc_
;
966 // The _GLOBAL_OFFSET_TABLE_ symbol.
967 Symbol
* global_offset_table_
;
968 // The dynamic reloc section.
969 Reloc_section
* rela_dyn_
;
970 // The section to use for IRELATIVE relocs.
971 Reloc_section
* rela_irelative_
;
972 // Relocs saved to avoid a COPY reloc.
973 Copy_relocs
<elfcpp::SHT_RELA
, size
, false> copy_relocs_
;
974 // Space for variables copied with a COPY reloc.
975 Output_data_space
* dynbss_
;
976 // Offset of the GOT entry for the TLS module index.
977 unsigned int got_mod_index_offset_
;
978 // We handle R_X86_64_TLSDESC against a local symbol as a target
979 // specific relocation. Here we store the object and local symbol
980 // index for the relocation.
981 std::vector
<Tlsdesc_info
> tlsdesc_reloc_info_
;
982 // True if the _TLS_MODULE_BASE_ symbol has been defined.
983 bool tls_base_symbol_defined_
;
987 const Target::Target_info Target_x86_64
<64>::x86_64_info
=
990 false, // is_big_endian
991 elfcpp::EM_X86_64
, // machine_code
992 false, // has_make_symbol
993 false, // has_resolve
994 true, // has_code_fill
995 true, // is_default_stack_executable
996 true, // can_icf_inline_merge_sections
998 "/lib/ld64.so.1", // program interpreter
999 0x400000, // default_text_segment_address
1000 0x1000, // abi_pagesize (overridable by -z max-page-size)
1001 0x1000, // common_pagesize (overridable by -z common-page-size)
1002 false, // isolate_execinstr
1004 elfcpp::SHN_UNDEF
, // small_common_shndx
1005 elfcpp::SHN_X86_64_LCOMMON
, // large_common_shndx
1006 0, // small_common_section_flags
1007 elfcpp::SHF_X86_64_LARGE
, // large_common_section_flags
1008 NULL
, // attributes_section
1009 NULL
// attributes_vendor
1013 const Target::Target_info Target_x86_64
<32>::x86_64_info
=
1016 false, // is_big_endian
1017 elfcpp::EM_X86_64
, // machine_code
1018 false, // has_make_symbol
1019 false, // has_resolve
1020 true, // has_code_fill
1021 true, // is_default_stack_executable
1022 true, // can_icf_inline_merge_sections
1024 "/libx32/ldx32.so.1", // program interpreter
1025 0x400000, // default_text_segment_address
1026 0x1000, // abi_pagesize (overridable by -z max-page-size)
1027 0x1000, // common_pagesize (overridable by -z common-page-size)
1028 false, // isolate_execinstr
1030 elfcpp::SHN_UNDEF
, // small_common_shndx
1031 elfcpp::SHN_X86_64_LCOMMON
, // large_common_shndx
1032 0, // small_common_section_flags
1033 elfcpp::SHF_X86_64_LARGE
, // large_common_section_flags
1034 NULL
, // attributes_section
1035 NULL
// attributes_vendor
1038 // This is called when a new output section is created. This is where
1039 // we handle the SHF_X86_64_LARGE.
1043 Target_x86_64
<size
>::do_new_output_section(Output_section
* os
) const
1045 if ((os
->flags() & elfcpp::SHF_X86_64_LARGE
) != 0)
1046 os
->set_is_large_section();
1049 // Get the GOT section, creating it if necessary.
1052 Output_data_got
<64, false>*
1053 Target_x86_64
<size
>::got_section(Symbol_table
* symtab
, Layout
* layout
)
1055 if (this->got_
== NULL
)
1057 gold_assert(symtab
!= NULL
&& layout
!= NULL
);
1059 // When using -z now, we can treat .got.plt as a relro section.
1060 // Without -z now, it is modified after program startup by lazy
1062 bool is_got_plt_relro
= parameters
->options().now();
1063 Output_section_order got_order
= (is_got_plt_relro
1065 : ORDER_RELRO_LAST
);
1066 Output_section_order got_plt_order
= (is_got_plt_relro
1068 : ORDER_NON_RELRO_FIRST
);
1070 this->got_
= new Output_data_got
<64, false>();
1072 layout
->add_output_section_data(".got", elfcpp::SHT_PROGBITS
,
1074 | elfcpp::SHF_WRITE
),
1075 this->got_
, got_order
, true);
1077 this->got_plt_
= new Output_data_space(8, "** GOT PLT");
1078 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
1080 | elfcpp::SHF_WRITE
),
1081 this->got_plt_
, got_plt_order
,
1084 // The first three entries are reserved.
1085 this->got_plt_
->set_current_data_size(3 * 8);
1087 if (!is_got_plt_relro
)
1089 // Those bytes can go into the relro segment.
1090 layout
->increase_relro(3 * 8);
1093 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
1094 this->global_offset_table_
=
1095 symtab
->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL
,
1096 Symbol_table::PREDEFINED
,
1098 0, 0, elfcpp::STT_OBJECT
,
1100 elfcpp::STV_HIDDEN
, 0,
1103 // If there are any IRELATIVE relocations, they get GOT entries
1104 // in .got.plt after the jump slot entries.
1105 this->got_irelative_
= new Output_data_space(8, "** GOT IRELATIVE PLT");
1106 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
1108 | elfcpp::SHF_WRITE
),
1109 this->got_irelative_
,
1110 got_plt_order
, is_got_plt_relro
);
1112 // If there are any TLSDESC relocations, they get GOT entries in
1113 // .got.plt after the jump slot and IRELATIVE entries.
1114 this->got_tlsdesc_
= new Output_data_got
<64, false>();
1115 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
1117 | elfcpp::SHF_WRITE
),
1119 got_plt_order
, is_got_plt_relro
);
1125 // Get the dynamic reloc section, creating it if necessary.
1128 typename Target_x86_64
<size
>::Reloc_section
*
1129 Target_x86_64
<size
>::rela_dyn_section(Layout
* layout
)
1131 if (this->rela_dyn_
== NULL
)
1133 gold_assert(layout
!= NULL
);
1134 this->rela_dyn_
= new Reloc_section(parameters
->options().combreloc());
1135 layout
->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA
,
1136 elfcpp::SHF_ALLOC
, this->rela_dyn_
,
1137 ORDER_DYNAMIC_RELOCS
, false);
1139 return this->rela_dyn_
;
1142 // Get the section to use for IRELATIVE relocs, creating it if
1143 // necessary. These go in .rela.dyn, but only after all other dynamic
1144 // relocations. They need to follow the other dynamic relocations so
1145 // that they can refer to global variables initialized by those
1149 typename Target_x86_64
<size
>::Reloc_section
*
1150 Target_x86_64
<size
>::rela_irelative_section(Layout
* layout
)
1152 if (this->rela_irelative_
== NULL
)
1154 // Make sure we have already created the dynamic reloc section.
1155 this->rela_dyn_section(layout
);
1156 this->rela_irelative_
= new Reloc_section(false);
1157 layout
->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA
,
1158 elfcpp::SHF_ALLOC
, this->rela_irelative_
,
1159 ORDER_DYNAMIC_RELOCS
, false);
1160 gold_assert(this->rela_dyn_
->output_section()
1161 == this->rela_irelative_
->output_section());
1163 return this->rela_irelative_
;
1166 // Initialize the PLT section.
1170 Output_data_plt_x86_64
<size
>::init(Layout
* layout
)
1172 this->rel_
= new Reloc_section(false);
1173 layout
->add_output_section_data(".rela.plt", elfcpp::SHT_RELA
,
1174 elfcpp::SHF_ALLOC
, this->rel_
,
1175 ORDER_DYNAMIC_PLT_RELOCS
, false);
1180 Output_data_plt_x86_64
<size
>::do_adjust_output_section(Output_section
* os
)
1182 os
->set_entsize(this->get_plt_entry_size());
1185 // Add an entry to the PLT.
1189 Output_data_plt_x86_64
<size
>::add_entry(Symbol_table
* symtab
, Layout
* layout
,
1192 gold_assert(!gsym
->has_plt_offset());
1194 unsigned int plt_index
;
1196 section_offset_type got_offset
;
1198 unsigned int* pcount
;
1199 unsigned int offset
;
1200 unsigned int reserved
;
1201 Output_data_space
* got
;
1202 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
1203 && gsym
->can_use_relative_reloc(false))
1205 pcount
= &this->irelative_count_
;
1208 got
= this->got_irelative_
;
1212 pcount
= &this->count_
;
1215 got
= this->got_plt_
;
1218 if (!this->is_data_size_valid())
1220 // Note that when setting the PLT offset for a non-IRELATIVE
1221 // entry we skip the initial reserved PLT entry.
1222 plt_index
= *pcount
+ offset
;
1223 plt_offset
= plt_index
* this->get_plt_entry_size();
1227 got_offset
= (plt_index
- offset
+ reserved
) * 8;
1228 gold_assert(got_offset
== got
->current_data_size());
1230 // Every PLT entry needs a GOT entry which points back to the PLT
1231 // entry (this will be changed by the dynamic linker, normally
1232 // lazily when the function is called).
1233 got
->set_current_data_size(got_offset
+ 8);
1237 // FIXME: This is probably not correct for IRELATIVE relocs.
1239 // For incremental updates, find an available slot.
1240 plt_offset
= this->free_list_
.allocate(this->get_plt_entry_size(),
1241 this->get_plt_entry_size(), 0);
1242 if (plt_offset
== -1)
1243 gold_fallback(_("out of patch space (PLT);"
1244 " relink with --incremental-full"));
1246 // The GOT and PLT entries have a 1-1 correspondance, so the GOT offset
1247 // can be calculated from the PLT index, adjusting for the three
1248 // reserved entries at the beginning of the GOT.
1249 plt_index
= plt_offset
/ this->get_plt_entry_size() - 1;
1250 got_offset
= (plt_index
- offset
+ reserved
) * 8;
1253 gsym
->set_plt_offset(plt_offset
);
1255 // Every PLT entry needs a reloc.
1256 this->add_relocation(symtab
, layout
, gsym
, got_offset
);
1258 // Note that we don't need to save the symbol. The contents of the
1259 // PLT are independent of which symbols are used. The symbols only
1260 // appear in the relocations.
1263 // Add an entry to the PLT for a local STT_GNU_IFUNC symbol. Return
1268 Output_data_plt_x86_64
<size
>::add_local_ifunc_entry(
1269 Symbol_table
* symtab
,
1271 Sized_relobj_file
<size
, false>* relobj
,
1272 unsigned int local_sym_index
)
1274 unsigned int plt_offset
= this->irelative_count_
* this->get_plt_entry_size();
1275 ++this->irelative_count_
;
1277 section_offset_type got_offset
= this->got_irelative_
->current_data_size();
1279 // Every PLT entry needs a GOT entry which points back to the PLT
1281 this->got_irelative_
->set_current_data_size(got_offset
+ 8);
1283 // Every PLT entry needs a reloc.
1284 Reloc_section
* rela
= this->rela_irelative(symtab
, layout
);
1285 rela
->add_symbolless_local_addend(relobj
, local_sym_index
,
1286 elfcpp::R_X86_64_IRELATIVE
,
1287 this->got_irelative_
, got_offset
, 0);
1292 // Add the relocation for a PLT entry.
1296 Output_data_plt_x86_64
<size
>::add_relocation(Symbol_table
* symtab
,
1299 unsigned int got_offset
)
1301 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
1302 && gsym
->can_use_relative_reloc(false))
1304 Reloc_section
* rela
= this->rela_irelative(symtab
, layout
);
1305 rela
->add_symbolless_global_addend(gsym
, elfcpp::R_X86_64_IRELATIVE
,
1306 this->got_irelative_
, got_offset
, 0);
1310 gsym
->set_needs_dynsym_entry();
1311 this->rel_
->add_global(gsym
, elfcpp::R_X86_64_JUMP_SLOT
, this->got_plt_
,
1316 // Return where the TLSDESC relocations should go, creating it if
1317 // necessary. These follow the JUMP_SLOT relocations.
1320 typename Output_data_plt_x86_64
<size
>::Reloc_section
*
1321 Output_data_plt_x86_64
<size
>::rela_tlsdesc(Layout
* layout
)
1323 if (this->tlsdesc_rel_
== NULL
)
1325 this->tlsdesc_rel_
= new Reloc_section(false);
1326 layout
->add_output_section_data(".rela.plt", elfcpp::SHT_RELA
,
1327 elfcpp::SHF_ALLOC
, this->tlsdesc_rel_
,
1328 ORDER_DYNAMIC_PLT_RELOCS
, false);
1329 gold_assert(this->tlsdesc_rel_
->output_section()
1330 == this->rel_
->output_section());
1332 return this->tlsdesc_rel_
;
1335 // Return where the IRELATIVE relocations should go in the PLT. These
1336 // follow the JUMP_SLOT and the TLSDESC relocations.
1339 typename Output_data_plt_x86_64
<size
>::Reloc_section
*
1340 Output_data_plt_x86_64
<size
>::rela_irelative(Symbol_table
* symtab
,
1343 if (this->irelative_rel_
== NULL
)
1345 // Make sure we have a place for the TLSDESC relocations, in
1346 // case we see any later on.
1347 this->rela_tlsdesc(layout
);
1348 this->irelative_rel_
= new Reloc_section(false);
1349 layout
->add_output_section_data(".rela.plt", elfcpp::SHT_RELA
,
1350 elfcpp::SHF_ALLOC
, this->irelative_rel_
,
1351 ORDER_DYNAMIC_PLT_RELOCS
, false);
1352 gold_assert(this->irelative_rel_
->output_section()
1353 == this->rel_
->output_section());
1355 if (parameters
->doing_static_link())
1357 // A statically linked executable will only have a .rela.plt
1358 // section to hold R_X86_64_IRELATIVE relocs for
1359 // STT_GNU_IFUNC symbols. The library will use these
1360 // symbols to locate the IRELATIVE relocs at program startup
1362 symtab
->define_in_output_data("__rela_iplt_start", NULL
,
1363 Symbol_table::PREDEFINED
,
1364 this->irelative_rel_
, 0, 0,
1365 elfcpp::STT_NOTYPE
, elfcpp::STB_GLOBAL
,
1366 elfcpp::STV_HIDDEN
, 0, false, true);
1367 symtab
->define_in_output_data("__rela_iplt_end", NULL
,
1368 Symbol_table::PREDEFINED
,
1369 this->irelative_rel_
, 0, 0,
1370 elfcpp::STT_NOTYPE
, elfcpp::STB_GLOBAL
,
1371 elfcpp::STV_HIDDEN
, 0, true, true);
1374 return this->irelative_rel_
;
1377 // Return the PLT address to use for a global symbol.
1381 Output_data_plt_x86_64
<size
>::address_for_global(const Symbol
* gsym
)
1383 uint64_t offset
= 0;
1384 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
1385 && gsym
->can_use_relative_reloc(false))
1386 offset
= (this->count_
+ 1) * this->get_plt_entry_size();
1387 return this->address() + offset
;
1390 // Return the PLT address to use for a local symbol. These are always
1391 // IRELATIVE relocs.
1395 Output_data_plt_x86_64
<size
>::address_for_local(const Relobj
*, unsigned int)
1397 return this->address() + (this->count_
+ 1) * this->get_plt_entry_size();
1400 // Set the final size.
1403 Output_data_plt_x86_64
<size
>::set_final_data_size()
1405 unsigned int count
= this->count_
+ this->irelative_count_
;
1406 if (this->has_tlsdesc_entry())
1408 this->set_data_size((count
+ 1) * this->get_plt_entry_size());
1411 // The first entry in the PLT for an executable.
1415 Output_data_plt_x86_64_standard
<size
>::first_plt_entry
[plt_entry_size
] =
1417 // From AMD64 ABI Draft 0.98, page 76
1418 0xff, 0x35, // pushq contents of memory address
1419 0, 0, 0, 0, // replaced with address of .got + 8
1420 0xff, 0x25, // jmp indirect
1421 0, 0, 0, 0, // replaced with address of .got + 16
1422 0x90, 0x90, 0x90, 0x90 // noop (x4)
1427 Output_data_plt_x86_64_standard
<size
>::do_fill_first_plt_entry(
1429 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
1430 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
)
1432 memcpy(pov
, first_plt_entry
, plt_entry_size
);
1433 // We do a jmp relative to the PC at the end of this instruction.
1434 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
1436 - (plt_address
+ 6)));
1437 elfcpp::Swap
<32, false>::writeval(pov
+ 8,
1439 - (plt_address
+ 12)));
1442 // Subsequent entries in the PLT for an executable.
1446 Output_data_plt_x86_64_standard
<size
>::plt_entry
[plt_entry_size
] =
1448 // From AMD64 ABI Draft 0.98, page 76
1449 0xff, 0x25, // jmpq indirect
1450 0, 0, 0, 0, // replaced with address of symbol in .got
1451 0x68, // pushq immediate
1452 0, 0, 0, 0, // replaced with offset into relocation table
1453 0xe9, // jmpq relative
1454 0, 0, 0, 0 // replaced with offset to start of .plt
1459 Output_data_plt_x86_64_standard
<size
>::do_fill_plt_entry(
1461 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
1462 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
1463 unsigned int got_offset
,
1464 unsigned int plt_offset
,
1465 unsigned int plt_index
)
1467 memcpy(pov
, plt_entry
, plt_entry_size
);
1468 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
1469 (got_address
+ got_offset
1470 - (plt_address
+ plt_offset
1473 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 7, plt_index
);
1474 elfcpp::Swap
<32, false>::writeval(pov
+ 12,
1475 - (plt_offset
+ plt_entry_size
));
1480 // The reserved TLSDESC entry in the PLT for an executable.
1484 Output_data_plt_x86_64_standard
<size
>::tlsdesc_plt_entry
[plt_entry_size
] =
1486 // From Alexandre Oliva, "Thread-Local Storage Descriptors for IA32
1487 // and AMD64/EM64T", Version 0.9.4 (2005-10-10).
1488 0xff, 0x35, // pushq x(%rip)
1489 0, 0, 0, 0, // replaced with address of linkmap GOT entry (at PLTGOT + 8)
1490 0xff, 0x25, // jmpq *y(%rip)
1491 0, 0, 0, 0, // replaced with offset of reserved TLSDESC_GOT entry
1498 Output_data_plt_x86_64_standard
<size
>::do_fill_tlsdesc_entry(
1500 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
1501 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
1502 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_base
,
1503 unsigned int tlsdesc_got_offset
,
1504 unsigned int plt_offset
)
1506 memcpy(pov
, tlsdesc_plt_entry
, plt_entry_size
);
1507 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
1509 - (plt_address
+ plt_offset
1511 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 8,
1513 + tlsdesc_got_offset
1514 - (plt_address
+ plt_offset
1518 // The .eh_frame unwind information for the PLT.
1522 Output_data_plt_x86_64
<size
>::plt_eh_frame_cie
[plt_eh_frame_cie_size
] =
1525 'z', // Augmentation: augmentation size included.
1526 'R', // Augmentation: FDE encoding included.
1527 '\0', // End of augmentation string.
1528 1, // Code alignment factor.
1529 0x78, // Data alignment factor.
1530 16, // Return address column.
1531 1, // Augmentation size.
1532 (elfcpp::DW_EH_PE_pcrel
// FDE encoding.
1533 | elfcpp::DW_EH_PE_sdata4
),
1534 elfcpp::DW_CFA_def_cfa
, 7, 8, // DW_CFA_def_cfa: r7 (rsp) ofs 8.
1535 elfcpp::DW_CFA_offset
+ 16, 1,// DW_CFA_offset: r16 (rip) at cfa-8.
1536 elfcpp::DW_CFA_nop
, // Align to 16 bytes.
1542 Output_data_plt_x86_64_standard
<size
>::plt_eh_frame_fde
[plt_eh_frame_fde_size
] =
1544 0, 0, 0, 0, // Replaced with offset to .plt.
1545 0, 0, 0, 0, // Replaced with size of .plt.
1546 0, // Augmentation size.
1547 elfcpp::DW_CFA_def_cfa_offset
, 16, // DW_CFA_def_cfa_offset: 16.
1548 elfcpp::DW_CFA_advance_loc
+ 6, // Advance 6 to __PLT__ + 6.
1549 elfcpp::DW_CFA_def_cfa_offset
, 24, // DW_CFA_def_cfa_offset: 24.
1550 elfcpp::DW_CFA_advance_loc
+ 10, // Advance 10 to __PLT__ + 16.
1551 elfcpp::DW_CFA_def_cfa_expression
, // DW_CFA_def_cfa_expression.
1552 11, // Block length.
1553 elfcpp::DW_OP_breg7
, 8, // Push %rsp + 8.
1554 elfcpp::DW_OP_breg16
, 0, // Push %rip.
1555 elfcpp::DW_OP_lit15
, // Push 0xf.
1556 elfcpp::DW_OP_and
, // & (%rip & 0xf).
1557 elfcpp::DW_OP_lit11
, // Push 0xb.
1558 elfcpp::DW_OP_ge
, // >= ((%rip & 0xf) >= 0xb)
1559 elfcpp::DW_OP_lit3
, // Push 3.
1560 elfcpp::DW_OP_shl
, // << (((%rip & 0xf) >= 0xb) << 3)
1561 elfcpp::DW_OP_plus
, // + ((((%rip&0xf)>=0xb)<<3)+%rsp+8
1562 elfcpp::DW_CFA_nop
, // Align to 32 bytes.
1568 // Write out the PLT. This uses the hand-coded instructions above,
1569 // and adjusts them as needed. This is specified by the AMD64 ABI.
1573 Output_data_plt_x86_64
<size
>::do_write(Output_file
* of
)
1575 const off_t offset
= this->offset();
1576 const section_size_type oview_size
=
1577 convert_to_section_size_type(this->data_size());
1578 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
1580 const off_t got_file_offset
= this->got_plt_
->offset();
1581 gold_assert(parameters
->incremental_update()
1582 || (got_file_offset
+ this->got_plt_
->data_size()
1583 == this->got_irelative_
->offset()));
1584 const section_size_type got_size
=
1585 convert_to_section_size_type(this->got_plt_
->data_size()
1586 + this->got_irelative_
->data_size());
1587 unsigned char* const got_view
= of
->get_output_view(got_file_offset
,
1590 unsigned char* pov
= oview
;
1592 // The base address of the .plt section.
1593 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
= this->address();
1594 // The base address of the .got section.
1595 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_base
= this->got_
->address();
1596 // The base address of the PLT portion of the .got section,
1597 // which is where the GOT pointer will point, and where the
1598 // three reserved GOT entries are located.
1599 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
1600 = this->got_plt_
->address();
1602 this->fill_first_plt_entry(pov
, got_address
, plt_address
);
1603 pov
+= this->get_plt_entry_size();
1605 unsigned char* got_pov
= got_view
;
1607 // The first entry in the GOT is the address of the .dynamic section
1608 // aka the PT_DYNAMIC segment. The next two entries are reserved.
1609 // We saved space for them when we created the section in
1610 // Target_x86_64::got_section.
1611 Output_section
* dynamic
= this->layout_
->dynamic_section();
1612 uint32_t dynamic_addr
= dynamic
== NULL
? 0 : dynamic
->address();
1613 elfcpp::Swap
<64, false>::writeval(got_pov
, dynamic_addr
);
1615 memset(got_pov
, 0, 16);
1618 unsigned int plt_offset
= this->get_plt_entry_size();
1619 unsigned int got_offset
= 24;
1620 const unsigned int count
= this->count_
+ this->irelative_count_
;
1621 for (unsigned int plt_index
= 0;
1624 pov
+= this->get_plt_entry_size(),
1626 plt_offset
+= this->get_plt_entry_size(),
1629 // Set and adjust the PLT entry itself.
1630 unsigned int lazy_offset
= this->fill_plt_entry(pov
,
1631 got_address
, plt_address
,
1632 got_offset
, plt_offset
,
1635 // Set the entry in the GOT.
1636 elfcpp::Swap
<64, false>::writeval(got_pov
,
1637 plt_address
+ plt_offset
+ lazy_offset
);
1640 if (this->has_tlsdesc_entry())
1642 // Set and adjust the reserved TLSDESC PLT entry.
1643 unsigned int tlsdesc_got_offset
= this->get_tlsdesc_got_offset();
1644 this->fill_tlsdesc_entry(pov
, got_address
, plt_address
, got_base
,
1645 tlsdesc_got_offset
, plt_offset
);
1646 pov
+= this->get_plt_entry_size();
1649 gold_assert(static_cast<section_size_type
>(pov
- oview
) == oview_size
);
1650 gold_assert(static_cast<section_size_type
>(got_pov
- got_view
) == got_size
);
1652 of
->write_output_view(offset
, oview_size
, oview
);
1653 of
->write_output_view(got_file_offset
, got_size
, got_view
);
1656 // Create the PLT section.
1660 Target_x86_64
<size
>::make_plt_section(Symbol_table
* symtab
, Layout
* layout
)
1662 if (this->plt_
== NULL
)
1664 // Create the GOT sections first.
1665 this->got_section(symtab
, layout
);
1667 this->plt_
= this->make_data_plt(layout
, this->got_
, this->got_plt_
,
1668 this->got_irelative_
);
1670 // Add unwind information if requested.
1671 if (parameters
->options().ld_generated_unwind_info())
1672 this->plt_
->add_eh_frame(layout
);
1674 layout
->add_output_section_data(".plt", elfcpp::SHT_PROGBITS
,
1676 | elfcpp::SHF_EXECINSTR
),
1677 this->plt_
, ORDER_PLT
, false);
1679 // Make the sh_info field of .rela.plt point to .plt.
1680 Output_section
* rela_plt_os
= this->plt_
->rela_plt()->output_section();
1681 rela_plt_os
->set_info_section(this->plt_
->output_section());
1685 // Return the section for TLSDESC relocations.
1688 typename Target_x86_64
<size
>::Reloc_section
*
1689 Target_x86_64
<size
>::rela_tlsdesc_section(Layout
* layout
) const
1691 return this->plt_section()->rela_tlsdesc(layout
);
1694 // Create a PLT entry for a global symbol.
1698 Target_x86_64
<size
>::make_plt_entry(Symbol_table
* symtab
, Layout
* layout
,
1701 if (gsym
->has_plt_offset())
1704 if (this->plt_
== NULL
)
1705 this->make_plt_section(symtab
, layout
);
1707 this->plt_
->add_entry(symtab
, layout
, gsym
);
1710 // Make a PLT entry for a local STT_GNU_IFUNC symbol.
1714 Target_x86_64
<size
>::make_local_ifunc_plt_entry(
1715 Symbol_table
* symtab
, Layout
* layout
,
1716 Sized_relobj_file
<size
, false>* relobj
,
1717 unsigned int local_sym_index
)
1719 if (relobj
->local_has_plt_offset(local_sym_index
))
1721 if (this->plt_
== NULL
)
1722 this->make_plt_section(symtab
, layout
);
1723 unsigned int plt_offset
= this->plt_
->add_local_ifunc_entry(symtab
, layout
,
1726 relobj
->set_local_plt_offset(local_sym_index
, plt_offset
);
1729 // Return the number of entries in the PLT.
1733 Target_x86_64
<size
>::plt_entry_count() const
1735 if (this->plt_
== NULL
)
1737 return this->plt_
->entry_count();
1740 // Return the offset of the first non-reserved PLT entry.
1744 Target_x86_64
<size
>::first_plt_entry_offset() const
1746 return this->plt_
->first_plt_entry_offset();
1749 // Return the size of each PLT entry.
1753 Target_x86_64
<size
>::plt_entry_size() const
1755 return this->plt_
->get_plt_entry_size();
1758 // Create the GOT and PLT sections for an incremental update.
1761 Output_data_got_base
*
1762 Target_x86_64
<size
>::init_got_plt_for_update(Symbol_table
* symtab
,
1764 unsigned int got_count
,
1765 unsigned int plt_count
)
1767 gold_assert(this->got_
== NULL
);
1769 this->got_
= new Output_data_got
<64, false>(got_count
* 8);
1770 layout
->add_output_section_data(".got", elfcpp::SHT_PROGBITS
,
1772 | elfcpp::SHF_WRITE
),
1773 this->got_
, ORDER_RELRO_LAST
,
1776 // Add the three reserved entries.
1777 this->got_plt_
= new Output_data_space((plt_count
+ 3) * 8, 8, "** GOT PLT");
1778 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
1780 | elfcpp::SHF_WRITE
),
1781 this->got_plt_
, ORDER_NON_RELRO_FIRST
,
1784 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
1785 this->global_offset_table_
=
1786 symtab
->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL
,
1787 Symbol_table::PREDEFINED
,
1789 0, 0, elfcpp::STT_OBJECT
,
1791 elfcpp::STV_HIDDEN
, 0,
1794 // If there are any TLSDESC relocations, they get GOT entries in
1795 // .got.plt after the jump slot entries.
1796 // FIXME: Get the count for TLSDESC entries.
1797 this->got_tlsdesc_
= new Output_data_got
<64, false>(0);
1798 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
1799 elfcpp::SHF_ALLOC
| elfcpp::SHF_WRITE
,
1801 ORDER_NON_RELRO_FIRST
, false);
1803 // If there are any IRELATIVE relocations, they get GOT entries in
1804 // .got.plt after the jump slot and TLSDESC entries.
1805 this->got_irelative_
= new Output_data_space(0, 8, "** GOT IRELATIVE PLT");
1806 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
1807 elfcpp::SHF_ALLOC
| elfcpp::SHF_WRITE
,
1808 this->got_irelative_
,
1809 ORDER_NON_RELRO_FIRST
, false);
1811 // Create the PLT section.
1812 this->plt_
= this->make_data_plt(layout
, this->got_
,
1814 this->got_irelative_
,
1817 // Add unwind information if requested.
1818 if (parameters
->options().ld_generated_unwind_info())
1819 this->plt_
->add_eh_frame(layout
);
1821 layout
->add_output_section_data(".plt", elfcpp::SHT_PROGBITS
,
1822 elfcpp::SHF_ALLOC
| elfcpp::SHF_EXECINSTR
,
1823 this->plt_
, ORDER_PLT
, false);
1825 // Make the sh_info field of .rela.plt point to .plt.
1826 Output_section
* rela_plt_os
= this->plt_
->rela_plt()->output_section();
1827 rela_plt_os
->set_info_section(this->plt_
->output_section());
1829 // Create the rela_dyn section.
1830 this->rela_dyn_section(layout
);
1835 // Reserve a GOT entry for a local symbol, and regenerate any
1836 // necessary dynamic relocations.
1840 Target_x86_64
<size
>::reserve_local_got_entry(
1841 unsigned int got_index
,
1842 Sized_relobj
<size
, false>* obj
,
1844 unsigned int got_type
)
1846 unsigned int got_offset
= got_index
* 8;
1847 Reloc_section
* rela_dyn
= this->rela_dyn_section(NULL
);
1849 this->got_
->reserve_local(got_index
, obj
, r_sym
, got_type
);
1852 case GOT_TYPE_STANDARD
:
1853 if (parameters
->options().output_is_position_independent())
1854 rela_dyn
->add_local_relative(obj
, r_sym
, elfcpp::R_X86_64_RELATIVE
,
1855 this->got_
, got_offset
, 0, false);
1857 case GOT_TYPE_TLS_OFFSET
:
1858 rela_dyn
->add_local(obj
, r_sym
, elfcpp::R_X86_64_TPOFF64
,
1859 this->got_
, got_offset
, 0);
1861 case GOT_TYPE_TLS_PAIR
:
1862 this->got_
->reserve_slot(got_index
+ 1);
1863 rela_dyn
->add_local(obj
, r_sym
, elfcpp::R_X86_64_DTPMOD64
,
1864 this->got_
, got_offset
, 0);
1866 case GOT_TYPE_TLS_DESC
:
1867 gold_fatal(_("TLS_DESC not yet supported for incremental linking"));
1868 // this->got_->reserve_slot(got_index + 1);
1869 // rela_dyn->add_target_specific(elfcpp::R_X86_64_TLSDESC, arg,
1870 // this->got_, got_offset, 0);
1877 // Reserve a GOT entry for a global symbol, and regenerate any
1878 // necessary dynamic relocations.
1882 Target_x86_64
<size
>::reserve_global_got_entry(unsigned int got_index
,
1884 unsigned int got_type
)
1886 unsigned int got_offset
= got_index
* 8;
1887 Reloc_section
* rela_dyn
= this->rela_dyn_section(NULL
);
1889 this->got_
->reserve_global(got_index
, gsym
, got_type
);
1892 case GOT_TYPE_STANDARD
:
1893 if (!gsym
->final_value_is_known())
1895 if (gsym
->is_from_dynobj()
1896 || gsym
->is_undefined()
1897 || gsym
->is_preemptible()
1898 || gsym
->type() == elfcpp::STT_GNU_IFUNC
)
1899 rela_dyn
->add_global(gsym
, elfcpp::R_X86_64_GLOB_DAT
,
1900 this->got_
, got_offset
, 0);
1902 rela_dyn
->add_global_relative(gsym
, elfcpp::R_X86_64_RELATIVE
,
1903 this->got_
, got_offset
, 0, false);
1906 case GOT_TYPE_TLS_OFFSET
:
1907 rela_dyn
->add_global_relative(gsym
, elfcpp::R_X86_64_TPOFF64
,
1908 this->got_
, got_offset
, 0, false);
1910 case GOT_TYPE_TLS_PAIR
:
1911 this->got_
->reserve_slot(got_index
+ 1);
1912 rela_dyn
->add_global_relative(gsym
, elfcpp::R_X86_64_DTPMOD64
,
1913 this->got_
, got_offset
, 0, false);
1914 rela_dyn
->add_global_relative(gsym
, elfcpp::R_X86_64_DTPOFF64
,
1915 this->got_
, got_offset
+ 8, 0, false);
1917 case GOT_TYPE_TLS_DESC
:
1918 this->got_
->reserve_slot(got_index
+ 1);
1919 rela_dyn
->add_global_relative(gsym
, elfcpp::R_X86_64_TLSDESC
,
1920 this->got_
, got_offset
, 0, false);
1927 // Register an existing PLT entry for a global symbol.
1931 Target_x86_64
<size
>::register_global_plt_entry(Symbol_table
* symtab
,
1933 unsigned int plt_index
,
1936 gold_assert(this->plt_
!= NULL
);
1937 gold_assert(!gsym
->has_plt_offset());
1939 this->plt_
->reserve_slot(plt_index
);
1941 gsym
->set_plt_offset((plt_index
+ 1) * this->plt_entry_size());
1943 unsigned int got_offset
= (plt_index
+ 3) * 8;
1944 this->plt_
->add_relocation(symtab
, layout
, gsym
, got_offset
);
1947 // Force a COPY relocation for a given symbol.
1951 Target_x86_64
<size
>::emit_copy_reloc(
1952 Symbol_table
* symtab
, Symbol
* sym
, Output_section
* os
, off_t offset
)
1954 this->copy_relocs_
.emit_copy_reloc(symtab
,
1955 symtab
->get_sized_symbol
<size
>(sym
),
1958 this->rela_dyn_section(NULL
));
1961 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
1965 Target_x86_64
<size
>::define_tls_base_symbol(Symbol_table
* symtab
,
1968 if (this->tls_base_symbol_defined_
)
1971 Output_segment
* tls_segment
= layout
->tls_segment();
1972 if (tls_segment
!= NULL
)
1974 bool is_exec
= parameters
->options().output_is_executable();
1975 symtab
->define_in_output_segment("_TLS_MODULE_BASE_", NULL
,
1976 Symbol_table::PREDEFINED
,
1980 elfcpp::STV_HIDDEN
, 0,
1982 ? Symbol::SEGMENT_END
1983 : Symbol::SEGMENT_START
),
1986 this->tls_base_symbol_defined_
= true;
1989 // Create the reserved PLT and GOT entries for the TLS descriptor resolver.
1993 Target_x86_64
<size
>::reserve_tlsdesc_entries(Symbol_table
* symtab
,
1996 if (this->plt_
== NULL
)
1997 this->make_plt_section(symtab
, layout
);
1999 if (!this->plt_
->has_tlsdesc_entry())
2001 // Allocate the TLSDESC_GOT entry.
2002 Output_data_got
<64, false>* got
= this->got_section(symtab
, layout
);
2003 unsigned int got_offset
= got
->add_constant(0);
2005 // Allocate the TLSDESC_PLT entry.
2006 this->plt_
->reserve_tlsdesc_entry(got_offset
);
2010 // Create a GOT entry for the TLS module index.
2014 Target_x86_64
<size
>::got_mod_index_entry(Symbol_table
* symtab
, Layout
* layout
,
2015 Sized_relobj_file
<size
, false>* object
)
2017 if (this->got_mod_index_offset_
== -1U)
2019 gold_assert(symtab
!= NULL
&& layout
!= NULL
&& object
!= NULL
);
2020 Reloc_section
* rela_dyn
= this->rela_dyn_section(layout
);
2021 Output_data_got
<64, false>* got
= this->got_section(symtab
, layout
);
2022 unsigned int got_offset
= got
->add_constant(0);
2023 rela_dyn
->add_local(object
, 0, elfcpp::R_X86_64_DTPMOD64
, got
,
2025 got
->add_constant(0);
2026 this->got_mod_index_offset_
= got_offset
;
2028 return this->got_mod_index_offset_
;
2031 // Optimize the TLS relocation type based on what we know about the
2032 // symbol. IS_FINAL is true if the final address of this symbol is
2033 // known at link time.
2036 tls::Tls_optimization
2037 Target_x86_64
<size
>::optimize_tls_reloc(bool is_final
, int r_type
)
2039 // If we are generating a shared library, then we can't do anything
2041 if (parameters
->options().shared())
2042 return tls::TLSOPT_NONE
;
2046 case elfcpp::R_X86_64_TLSGD
:
2047 case elfcpp::R_X86_64_GOTPC32_TLSDESC
:
2048 case elfcpp::R_X86_64_TLSDESC_CALL
:
2049 // These are General-Dynamic which permits fully general TLS
2050 // access. Since we know that we are generating an executable,
2051 // we can convert this to Initial-Exec. If we also know that
2052 // this is a local symbol, we can further switch to Local-Exec.
2054 return tls::TLSOPT_TO_LE
;
2055 return tls::TLSOPT_TO_IE
;
2057 case elfcpp::R_X86_64_TLSLD
:
2058 // This is Local-Dynamic, which refers to a local symbol in the
2059 // dynamic TLS block. Since we know that we generating an
2060 // executable, we can switch to Local-Exec.
2061 return tls::TLSOPT_TO_LE
;
2063 case elfcpp::R_X86_64_DTPOFF32
:
2064 case elfcpp::R_X86_64_DTPOFF64
:
2065 // Another Local-Dynamic reloc.
2066 return tls::TLSOPT_TO_LE
;
2068 case elfcpp::R_X86_64_GOTTPOFF
:
2069 // These are Initial-Exec relocs which get the thread offset
2070 // from the GOT. If we know that we are linking against the
2071 // local symbol, we can switch to Local-Exec, which links the
2072 // thread offset into the instruction.
2074 return tls::TLSOPT_TO_LE
;
2075 return tls::TLSOPT_NONE
;
2077 case elfcpp::R_X86_64_TPOFF32
:
2078 // When we already have Local-Exec, there is nothing further we
2080 return tls::TLSOPT_NONE
;
2087 // Get the Reference_flags for a particular relocation.
2091 Target_x86_64
<size
>::Scan::get_reference_flags(unsigned int r_type
)
2095 case elfcpp::R_X86_64_NONE
:
2096 case elfcpp::R_X86_64_GNU_VTINHERIT
:
2097 case elfcpp::R_X86_64_GNU_VTENTRY
:
2098 case elfcpp::R_X86_64_GOTPC32
:
2099 case elfcpp::R_X86_64_GOTPC64
:
2100 // No symbol reference.
2103 case elfcpp::R_X86_64_64
:
2104 case elfcpp::R_X86_64_32
:
2105 case elfcpp::R_X86_64_32S
:
2106 case elfcpp::R_X86_64_16
:
2107 case elfcpp::R_X86_64_8
:
2108 return Symbol::ABSOLUTE_REF
;
2110 case elfcpp::R_X86_64_PC64
:
2111 case elfcpp::R_X86_64_PC32
:
2112 case elfcpp::R_X86_64_PC16
:
2113 case elfcpp::R_X86_64_PC8
:
2114 case elfcpp::R_X86_64_GOTOFF64
:
2115 return Symbol::RELATIVE_REF
;
2117 case elfcpp::R_X86_64_PLT32
:
2118 case elfcpp::R_X86_64_PLTOFF64
:
2119 return Symbol::FUNCTION_CALL
| Symbol::RELATIVE_REF
;
2121 case elfcpp::R_X86_64_GOT64
:
2122 case elfcpp::R_X86_64_GOT32
:
2123 case elfcpp::R_X86_64_GOTPCREL64
:
2124 case elfcpp::R_X86_64_GOTPCREL
:
2125 case elfcpp::R_X86_64_GOTPLT64
:
2127 return Symbol::ABSOLUTE_REF
;
2129 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
2130 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
2131 case elfcpp::R_X86_64_TLSDESC_CALL
:
2132 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
2133 case elfcpp::R_X86_64_DTPOFF32
:
2134 case elfcpp::R_X86_64_DTPOFF64
:
2135 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
2136 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
2137 return Symbol::TLS_REF
;
2139 case elfcpp::R_X86_64_COPY
:
2140 case elfcpp::R_X86_64_GLOB_DAT
:
2141 case elfcpp::R_X86_64_JUMP_SLOT
:
2142 case elfcpp::R_X86_64_RELATIVE
:
2143 case elfcpp::R_X86_64_IRELATIVE
:
2144 case elfcpp::R_X86_64_TPOFF64
:
2145 case elfcpp::R_X86_64_DTPMOD64
:
2146 case elfcpp::R_X86_64_TLSDESC
:
2147 case elfcpp::R_X86_64_SIZE32
:
2148 case elfcpp::R_X86_64_SIZE64
:
2150 // Not expected. We will give an error later.
2155 // Report an unsupported relocation against a local symbol.
2159 Target_x86_64
<size
>::Scan::unsupported_reloc_local(
2160 Sized_relobj_file
<size
, false>* object
,
2161 unsigned int r_type
)
2163 gold_error(_("%s: unsupported reloc %u against local symbol"),
2164 object
->name().c_str(), r_type
);
2167 // We are about to emit a dynamic relocation of type R_TYPE. If the
2168 // dynamic linker does not support it, issue an error. The GNU linker
2169 // only issues a non-PIC error for an allocated read-only section.
2170 // Here we know the section is allocated, but we don't know that it is
2171 // read-only. But we check for all the relocation types which the
2172 // glibc dynamic linker supports, so it seems appropriate to issue an
2173 // error even if the section is not read-only. If GSYM is not NULL,
2174 // it is the symbol the relocation is against; if it is NULL, the
2175 // relocation is against a local symbol.
2179 Target_x86_64
<size
>::Scan::check_non_pic(Relobj
* object
, unsigned int r_type
,
2184 // These are the relocation types supported by glibc for x86_64
2185 // which should always work.
2186 case elfcpp::R_X86_64_RELATIVE
:
2187 case elfcpp::R_X86_64_IRELATIVE
:
2188 case elfcpp::R_X86_64_GLOB_DAT
:
2189 case elfcpp::R_X86_64_JUMP_SLOT
:
2190 case elfcpp::R_X86_64_DTPMOD64
:
2191 case elfcpp::R_X86_64_DTPOFF64
:
2192 case elfcpp::R_X86_64_TPOFF64
:
2193 case elfcpp::R_X86_64_64
:
2194 case elfcpp::R_X86_64_COPY
:
2197 // glibc supports these reloc types, but they can overflow.
2198 case elfcpp::R_X86_64_PC32
:
2199 // A PC relative reference is OK against a local symbol or if
2200 // the symbol is defined locally.
2202 || (!gsym
->is_from_dynobj()
2203 && !gsym
->is_undefined()
2204 && !gsym
->is_preemptible()))
2207 case elfcpp::R_X86_64_32
:
2208 // R_X86_64_32 is OK for x32.
2209 if (size
== 32 && r_type
== elfcpp::R_X86_64_32
)
2211 if (this->issued_non_pic_error_
)
2213 gold_assert(parameters
->options().output_is_position_independent());
2215 object
->error(_("requires dynamic R_X86_64_32 reloc which may "
2216 "overflow at runtime; recompile with -fPIC"));
2218 object
->error(_("requires dynamic %s reloc against '%s' which may "
2219 "overflow at runtime; recompile with -fPIC"),
2220 (r_type
== elfcpp::R_X86_64_32
2224 this->issued_non_pic_error_
= true;
2228 // This prevents us from issuing more than one error per reloc
2229 // section. But we can still wind up issuing more than one
2230 // error per object file.
2231 if (this->issued_non_pic_error_
)
2233 gold_assert(parameters
->options().output_is_position_independent());
2234 object
->error(_("requires unsupported dynamic reloc %u; "
2235 "recompile with -fPIC"),
2237 this->issued_non_pic_error_
= true;
2240 case elfcpp::R_X86_64_NONE
:
2245 // Return whether we need to make a PLT entry for a relocation of the
2246 // given type against a STT_GNU_IFUNC symbol.
2250 Target_x86_64
<size
>::Scan::reloc_needs_plt_for_ifunc(
2251 Sized_relobj_file
<size
, false>* object
,
2252 unsigned int r_type
)
2254 int flags
= Scan::get_reference_flags(r_type
);
2255 if (flags
& Symbol::TLS_REF
)
2256 gold_error(_("%s: unsupported TLS reloc %u for IFUNC symbol"),
2257 object
->name().c_str(), r_type
);
2261 // Scan a relocation for a local symbol.
2265 Target_x86_64
<size
>::Scan::local(Symbol_table
* symtab
,
2267 Target_x86_64
<size
>* target
,
2268 Sized_relobj_file
<size
, false>* object
,
2269 unsigned int data_shndx
,
2270 Output_section
* output_section
,
2271 const elfcpp::Rela
<size
, false>& reloc
,
2272 unsigned int r_type
,
2273 const elfcpp::Sym
<size
, false>& lsym
)
2275 // A local STT_GNU_IFUNC symbol may require a PLT entry.
2276 bool is_ifunc
= lsym
.get_st_type() == elfcpp::STT_GNU_IFUNC
;
2277 if (is_ifunc
&& this->reloc_needs_plt_for_ifunc(object
, r_type
))
2279 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(reloc
.get_r_info());
2280 target
->make_local_ifunc_plt_entry(symtab
, layout
, object
, r_sym
);
2285 case elfcpp::R_X86_64_NONE
:
2286 case elfcpp::R_X86_64_GNU_VTINHERIT
:
2287 case elfcpp::R_X86_64_GNU_VTENTRY
:
2290 case elfcpp::R_X86_64_64
:
2291 // If building a shared library (or a position-independent
2292 // executable), we need to create a dynamic relocation for this
2293 // location. The relocation applied at link time will apply the
2294 // link-time value, so we flag the location with an
2295 // R_X86_64_RELATIVE relocation so the dynamic loader can
2296 // relocate it easily.
2297 if (parameters
->options().output_is_position_independent())
2299 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(reloc
.get_r_info());
2300 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
2301 rela_dyn
->add_local_relative(object
, r_sym
,
2303 ? elfcpp::R_X86_64_RELATIVE64
2304 : elfcpp::R_X86_64_RELATIVE
),
2305 output_section
, data_shndx
,
2306 reloc
.get_r_offset(),
2307 reloc
.get_r_addend(), is_ifunc
);
2311 case elfcpp::R_X86_64_32
:
2312 case elfcpp::R_X86_64_32S
:
2313 case elfcpp::R_X86_64_16
:
2314 case elfcpp::R_X86_64_8
:
2315 // If building a shared library (or a position-independent
2316 // executable), we need to create a dynamic relocation for this
2317 // location. We can't use an R_X86_64_RELATIVE relocation
2318 // because that is always a 64-bit relocation.
2319 if (parameters
->options().output_is_position_independent())
2321 // Use R_X86_64_RELATIVE relocation for R_X86_64_32 under x32.
2322 if (size
== 32 && r_type
== elfcpp::R_X86_64_32
)
2324 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(reloc
.get_r_info());
2325 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
2326 rela_dyn
->add_local_relative(object
, r_sym
,
2327 elfcpp::R_X86_64_RELATIVE
,
2328 output_section
, data_shndx
,
2329 reloc
.get_r_offset(),
2330 reloc
.get_r_addend(), is_ifunc
);
2334 this->check_non_pic(object
, r_type
, NULL
);
2336 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
2337 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(reloc
.get_r_info());
2338 if (lsym
.get_st_type() != elfcpp::STT_SECTION
)
2339 rela_dyn
->add_local(object
, r_sym
, r_type
, output_section
,
2340 data_shndx
, reloc
.get_r_offset(),
2341 reloc
.get_r_addend());
2344 gold_assert(lsym
.get_st_value() == 0);
2345 unsigned int shndx
= lsym
.get_st_shndx();
2347 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
,
2350 object
->error(_("section symbol %u has bad shndx %u"),
2353 rela_dyn
->add_local_section(object
, shndx
,
2354 r_type
, output_section
,
2355 data_shndx
, reloc
.get_r_offset(),
2356 reloc
.get_r_addend());
2361 case elfcpp::R_X86_64_PC64
:
2362 case elfcpp::R_X86_64_PC32
:
2363 case elfcpp::R_X86_64_PC16
:
2364 case elfcpp::R_X86_64_PC8
:
2367 case elfcpp::R_X86_64_PLT32
:
2368 // Since we know this is a local symbol, we can handle this as a
2372 case elfcpp::R_X86_64_GOTPC32
:
2373 case elfcpp::R_X86_64_GOTOFF64
:
2374 case elfcpp::R_X86_64_GOTPC64
:
2375 case elfcpp::R_X86_64_PLTOFF64
:
2376 // We need a GOT section.
2377 target
->got_section(symtab
, layout
);
2378 // For PLTOFF64, we'd normally want a PLT section, but since we
2379 // know this is a local symbol, no PLT is needed.
2382 case elfcpp::R_X86_64_GOT64
:
2383 case elfcpp::R_X86_64_GOT32
:
2384 case elfcpp::R_X86_64_GOTPCREL64
:
2385 case elfcpp::R_X86_64_GOTPCREL
:
2386 case elfcpp::R_X86_64_GOTPLT64
:
2388 // The symbol requires a GOT entry.
2389 Output_data_got
<64, false>* got
= target
->got_section(symtab
, layout
);
2390 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(reloc
.get_r_info());
2392 // For a STT_GNU_IFUNC symbol we want the PLT offset. That
2393 // lets function pointers compare correctly with shared
2394 // libraries. Otherwise we would need an IRELATIVE reloc.
2397 is_new
= got
->add_local_plt(object
, r_sym
, GOT_TYPE_STANDARD
);
2399 is_new
= got
->add_local(object
, r_sym
, GOT_TYPE_STANDARD
);
2402 // If we are generating a shared object, we need to add a
2403 // dynamic relocation for this symbol's GOT entry.
2404 if (parameters
->options().output_is_position_independent())
2406 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
2407 // R_X86_64_RELATIVE assumes a 64-bit relocation.
2408 if (r_type
!= elfcpp::R_X86_64_GOT32
)
2410 unsigned int got_offset
=
2411 object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
);
2412 rela_dyn
->add_local_relative(object
, r_sym
,
2413 elfcpp::R_X86_64_RELATIVE
,
2414 got
, got_offset
, 0, is_ifunc
);
2418 this->check_non_pic(object
, r_type
, NULL
);
2420 gold_assert(lsym
.get_st_type() != elfcpp::STT_SECTION
);
2421 rela_dyn
->add_local(
2422 object
, r_sym
, r_type
, got
,
2423 object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
), 0);
2427 // For GOTPLT64, we'd normally want a PLT section, but since
2428 // we know this is a local symbol, no PLT is needed.
2432 case elfcpp::R_X86_64_COPY
:
2433 case elfcpp::R_X86_64_GLOB_DAT
:
2434 case elfcpp::R_X86_64_JUMP_SLOT
:
2435 case elfcpp::R_X86_64_RELATIVE
:
2436 case elfcpp::R_X86_64_IRELATIVE
:
2437 // These are outstanding tls relocs, which are unexpected when linking
2438 case elfcpp::R_X86_64_TPOFF64
:
2439 case elfcpp::R_X86_64_DTPMOD64
:
2440 case elfcpp::R_X86_64_TLSDESC
:
2441 gold_error(_("%s: unexpected reloc %u in object file"),
2442 object
->name().c_str(), r_type
);
2445 // These are initial tls relocs, which are expected when linking
2446 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
2447 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
2448 case elfcpp::R_X86_64_TLSDESC_CALL
:
2449 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
2450 case elfcpp::R_X86_64_DTPOFF32
:
2451 case elfcpp::R_X86_64_DTPOFF64
:
2452 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
2453 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
2455 bool output_is_shared
= parameters
->options().shared();
2456 const tls::Tls_optimization optimized_type
2457 = Target_x86_64
<size
>::optimize_tls_reloc(!output_is_shared
,
2461 case elfcpp::R_X86_64_TLSGD
: // General-dynamic
2462 if (optimized_type
== tls::TLSOPT_NONE
)
2464 // Create a pair of GOT entries for the module index and
2465 // dtv-relative offset.
2466 Output_data_got
<64, false>* got
2467 = target
->got_section(symtab
, layout
);
2468 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(reloc
.get_r_info());
2469 unsigned int shndx
= lsym
.get_st_shndx();
2471 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
, &is_ordinary
);
2473 object
->error(_("local symbol %u has bad shndx %u"),
2476 got
->add_local_pair_with_rel(object
, r_sym
,
2479 target
->rela_dyn_section(layout
),
2480 elfcpp::R_X86_64_DTPMOD64
, 0);
2482 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2483 unsupported_reloc_local(object
, r_type
);
2486 case elfcpp::R_X86_64_GOTPC32_TLSDESC
:
2487 target
->define_tls_base_symbol(symtab
, layout
);
2488 if (optimized_type
== tls::TLSOPT_NONE
)
2490 // Create reserved PLT and GOT entries for the resolver.
2491 target
->reserve_tlsdesc_entries(symtab
, layout
);
2493 // Generate a double GOT entry with an
2494 // R_X86_64_TLSDESC reloc. The R_X86_64_TLSDESC reloc
2495 // is resolved lazily, so the GOT entry needs to be in
2496 // an area in .got.plt, not .got. Call got_section to
2497 // make sure the section has been created.
2498 target
->got_section(symtab
, layout
);
2499 Output_data_got
<64, false>* got
= target
->got_tlsdesc_section();
2500 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(reloc
.get_r_info());
2501 if (!object
->local_has_got_offset(r_sym
, GOT_TYPE_TLS_DESC
))
2503 unsigned int got_offset
= got
->add_constant(0);
2504 got
->add_constant(0);
2505 object
->set_local_got_offset(r_sym
, GOT_TYPE_TLS_DESC
,
2507 Reloc_section
* rt
= target
->rela_tlsdesc_section(layout
);
2508 // We store the arguments we need in a vector, and
2509 // use the index into the vector as the parameter
2510 // to pass to the target specific routines.
2511 uintptr_t intarg
= target
->add_tlsdesc_info(object
, r_sym
);
2512 void* arg
= reinterpret_cast<void*>(intarg
);
2513 rt
->add_target_specific(elfcpp::R_X86_64_TLSDESC
, arg
,
2514 got
, got_offset
, 0);
2517 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2518 unsupported_reloc_local(object
, r_type
);
2521 case elfcpp::R_X86_64_TLSDESC_CALL
:
2524 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
2525 if (optimized_type
== tls::TLSOPT_NONE
)
2527 // Create a GOT entry for the module index.
2528 target
->got_mod_index_entry(symtab
, layout
, object
);
2530 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2531 unsupported_reloc_local(object
, r_type
);
2534 case elfcpp::R_X86_64_DTPOFF32
:
2535 case elfcpp::R_X86_64_DTPOFF64
:
2538 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
2539 layout
->set_has_static_tls();
2540 if (optimized_type
== tls::TLSOPT_NONE
)
2542 // Create a GOT entry for the tp-relative offset.
2543 Output_data_got
<64, false>* got
2544 = target
->got_section(symtab
, layout
);
2545 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(reloc
.get_r_info());
2546 got
->add_local_with_rel(object
, r_sym
, GOT_TYPE_TLS_OFFSET
,
2547 target
->rela_dyn_section(layout
),
2548 elfcpp::R_X86_64_TPOFF64
);
2550 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2551 unsupported_reloc_local(object
, r_type
);
2554 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
2555 layout
->set_has_static_tls();
2556 if (output_is_shared
)
2557 unsupported_reloc_local(object
, r_type
);
2566 case elfcpp::R_X86_64_SIZE32
:
2567 case elfcpp::R_X86_64_SIZE64
:
2569 gold_error(_("%s: unsupported reloc %u against local symbol"),
2570 object
->name().c_str(), r_type
);
2576 // Report an unsupported relocation against a global symbol.
2580 Target_x86_64
<size
>::Scan::unsupported_reloc_global(
2581 Sized_relobj_file
<size
, false>* object
,
2582 unsigned int r_type
,
2585 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
2586 object
->name().c_str(), r_type
, gsym
->demangled_name().c_str());
2589 // Returns true if this relocation type could be that of a function pointer.
2592 Target_x86_64
<size
>::Scan::possible_function_pointer_reloc(unsigned int r_type
)
2596 case elfcpp::R_X86_64_64
:
2597 case elfcpp::R_X86_64_32
:
2598 case elfcpp::R_X86_64_32S
:
2599 case elfcpp::R_X86_64_16
:
2600 case elfcpp::R_X86_64_8
:
2601 case elfcpp::R_X86_64_GOT64
:
2602 case elfcpp::R_X86_64_GOT32
:
2603 case elfcpp::R_X86_64_GOTPCREL64
:
2604 case elfcpp::R_X86_64_GOTPCREL
:
2605 case elfcpp::R_X86_64_GOTPLT64
:
2613 // For safe ICF, scan a relocation for a local symbol to check if it
2614 // corresponds to a function pointer being taken. In that case mark
2615 // the function whose pointer was taken as not foldable.
2619 Target_x86_64
<size
>::Scan::local_reloc_may_be_function_pointer(
2622 Target_x86_64
<size
>* ,
2623 Sized_relobj_file
<size
, false>* ,
2626 const elfcpp::Rela
<size
, false>& ,
2627 unsigned int r_type
,
2628 const elfcpp::Sym
<size
, false>&)
2630 // When building a shared library, do not fold any local symbols as it is
2631 // not possible to distinguish pointer taken versus a call by looking at
2632 // the relocation types.
2633 return (parameters
->options().shared()
2634 || possible_function_pointer_reloc(r_type
));
2637 // For safe ICF, scan a relocation for a global symbol to check if it
2638 // corresponds to a function pointer being taken. In that case mark
2639 // the function whose pointer was taken as not foldable.
2643 Target_x86_64
<size
>::Scan::global_reloc_may_be_function_pointer(
2646 Target_x86_64
<size
>* ,
2647 Sized_relobj_file
<size
, false>* ,
2650 const elfcpp::Rela
<size
, false>& ,
2651 unsigned int r_type
,
2654 // When building a shared library, do not fold symbols whose visibility
2655 // is hidden, internal or protected.
2656 return ((parameters
->options().shared()
2657 && (gsym
->visibility() == elfcpp::STV_INTERNAL
2658 || gsym
->visibility() == elfcpp::STV_PROTECTED
2659 || gsym
->visibility() == elfcpp::STV_HIDDEN
))
2660 || possible_function_pointer_reloc(r_type
));
2663 // Scan a relocation for a global symbol.
2667 Target_x86_64
<size
>::Scan::global(Symbol_table
* symtab
,
2669 Target_x86_64
<size
>* target
,
2670 Sized_relobj_file
<size
, false>* object
,
2671 unsigned int data_shndx
,
2672 Output_section
* output_section
,
2673 const elfcpp::Rela
<size
, false>& reloc
,
2674 unsigned int r_type
,
2677 // A STT_GNU_IFUNC symbol may require a PLT entry.
2678 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
2679 && this->reloc_needs_plt_for_ifunc(object
, r_type
))
2680 target
->make_plt_entry(symtab
, layout
, gsym
);
2684 case elfcpp::R_X86_64_NONE
:
2685 case elfcpp::R_X86_64_GNU_VTINHERIT
:
2686 case elfcpp::R_X86_64_GNU_VTENTRY
:
2689 case elfcpp::R_X86_64_64
:
2690 case elfcpp::R_X86_64_32
:
2691 case elfcpp::R_X86_64_32S
:
2692 case elfcpp::R_X86_64_16
:
2693 case elfcpp::R_X86_64_8
:
2695 // Make a PLT entry if necessary.
2696 if (gsym
->needs_plt_entry())
2698 target
->make_plt_entry(symtab
, layout
, gsym
);
2699 // Since this is not a PC-relative relocation, we may be
2700 // taking the address of a function. In that case we need to
2701 // set the entry in the dynamic symbol table to the address of
2703 if (gsym
->is_from_dynobj() && !parameters
->options().shared())
2704 gsym
->set_needs_dynsym_value();
2706 // Make a dynamic relocation if necessary.
2707 if (gsym
->needs_dynamic_reloc(Scan::get_reference_flags(r_type
)))
2709 if (gsym
->may_need_copy_reloc())
2711 target
->copy_reloc(symtab
, layout
, object
,
2712 data_shndx
, output_section
, gsym
, reloc
);
2714 else if (((size
== 64 && r_type
== elfcpp::R_X86_64_64
)
2715 || (size
== 32 && r_type
== elfcpp::R_X86_64_32
))
2716 && gsym
->type() == elfcpp::STT_GNU_IFUNC
2717 && gsym
->can_use_relative_reloc(false)
2718 && !gsym
->is_from_dynobj()
2719 && !gsym
->is_undefined()
2720 && !gsym
->is_preemptible())
2722 // Use an IRELATIVE reloc for a locally defined
2723 // STT_GNU_IFUNC symbol. This makes a function
2724 // address in a PIE executable match the address in a
2725 // shared library that it links against.
2726 Reloc_section
* rela_dyn
=
2727 target
->rela_irelative_section(layout
);
2728 unsigned int r_type
= elfcpp::R_X86_64_IRELATIVE
;
2729 rela_dyn
->add_symbolless_global_addend(gsym
, r_type
,
2730 output_section
, object
,
2732 reloc
.get_r_offset(),
2733 reloc
.get_r_addend());
2735 else if (r_type
== elfcpp::R_X86_64_64
2736 && gsym
->can_use_relative_reloc(false))
2738 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
2739 rela_dyn
->add_global_relative(gsym
, elfcpp::R_X86_64_RELATIVE
,
2740 output_section
, object
,
2742 reloc
.get_r_offset(),
2743 reloc
.get_r_addend(), false);
2747 this->check_non_pic(object
, r_type
, gsym
);
2748 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
2749 rela_dyn
->add_global(gsym
, r_type
, output_section
, object
,
2750 data_shndx
, reloc
.get_r_offset(),
2751 reloc
.get_r_addend());
2757 case elfcpp::R_X86_64_PC64
:
2758 case elfcpp::R_X86_64_PC32
:
2759 case elfcpp::R_X86_64_PC16
:
2760 case elfcpp::R_X86_64_PC8
:
2762 // Make a PLT entry if necessary.
2763 if (gsym
->needs_plt_entry())
2764 target
->make_plt_entry(symtab
, layout
, gsym
);
2765 // Make a dynamic relocation if necessary.
2766 if (gsym
->needs_dynamic_reloc(Scan::get_reference_flags(r_type
)))
2768 if (gsym
->may_need_copy_reloc())
2770 target
->copy_reloc(symtab
, layout
, object
,
2771 data_shndx
, output_section
, gsym
, reloc
);
2775 this->check_non_pic(object
, r_type
, gsym
);
2776 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
2777 rela_dyn
->add_global(gsym
, r_type
, output_section
, object
,
2778 data_shndx
, reloc
.get_r_offset(),
2779 reloc
.get_r_addend());
2785 case elfcpp::R_X86_64_GOT64
:
2786 case elfcpp::R_X86_64_GOT32
:
2787 case elfcpp::R_X86_64_GOTPCREL64
:
2788 case elfcpp::R_X86_64_GOTPCREL
:
2789 case elfcpp::R_X86_64_GOTPLT64
:
2791 // The symbol requires a GOT entry.
2792 Output_data_got
<64, false>* got
= target
->got_section(symtab
, layout
);
2793 if (gsym
->final_value_is_known())
2795 // For a STT_GNU_IFUNC symbol we want the PLT address.
2796 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
)
2797 got
->add_global_plt(gsym
, GOT_TYPE_STANDARD
);
2799 got
->add_global(gsym
, GOT_TYPE_STANDARD
);
2803 // If this symbol is not fully resolved, we need to add a
2804 // dynamic relocation for it.
2805 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
2807 // Use a GLOB_DAT rather than a RELATIVE reloc if:
2809 // 1) The symbol may be defined in some other module.
2811 // 2) We are building a shared library and this is a
2812 // protected symbol; using GLOB_DAT means that the dynamic
2813 // linker can use the address of the PLT in the main
2814 // executable when appropriate so that function address
2815 // comparisons work.
2817 // 3) This is a STT_GNU_IFUNC symbol in position dependent
2818 // code, again so that function address comparisons work.
2819 if (gsym
->is_from_dynobj()
2820 || gsym
->is_undefined()
2821 || gsym
->is_preemptible()
2822 || (gsym
->visibility() == elfcpp::STV_PROTECTED
2823 && parameters
->options().shared())
2824 || (gsym
->type() == elfcpp::STT_GNU_IFUNC
2825 && parameters
->options().output_is_position_independent()))
2826 got
->add_global_with_rel(gsym
, GOT_TYPE_STANDARD
, rela_dyn
,
2827 elfcpp::R_X86_64_GLOB_DAT
);
2830 // For a STT_GNU_IFUNC symbol we want to write the PLT
2831 // offset into the GOT, so that function pointer
2832 // comparisons work correctly.
2834 if (gsym
->type() != elfcpp::STT_GNU_IFUNC
)
2835 is_new
= got
->add_global(gsym
, GOT_TYPE_STANDARD
);
2838 is_new
= got
->add_global_plt(gsym
, GOT_TYPE_STANDARD
);
2839 // Tell the dynamic linker to use the PLT address
2840 // when resolving relocations.
2841 if (gsym
->is_from_dynobj()
2842 && !parameters
->options().shared())
2843 gsym
->set_needs_dynsym_value();
2847 unsigned int got_off
= gsym
->got_offset(GOT_TYPE_STANDARD
);
2848 rela_dyn
->add_global_relative(gsym
,
2849 elfcpp::R_X86_64_RELATIVE
,
2850 got
, got_off
, 0, false);
2854 // For GOTPLT64, we also need a PLT entry (but only if the
2855 // symbol is not fully resolved).
2856 if (r_type
== elfcpp::R_X86_64_GOTPLT64
2857 && !gsym
->final_value_is_known())
2858 target
->make_plt_entry(symtab
, layout
, gsym
);
2862 case elfcpp::R_X86_64_PLT32
:
2863 // If the symbol is fully resolved, this is just a PC32 reloc.
2864 // Otherwise we need a PLT entry.
2865 if (gsym
->final_value_is_known())
2867 // If building a shared library, we can also skip the PLT entry
2868 // if the symbol is defined in the output file and is protected
2870 if (gsym
->is_defined()
2871 && !gsym
->is_from_dynobj()
2872 && !gsym
->is_preemptible())
2874 target
->make_plt_entry(symtab
, layout
, gsym
);
2877 case elfcpp::R_X86_64_GOTPC32
:
2878 case elfcpp::R_X86_64_GOTOFF64
:
2879 case elfcpp::R_X86_64_GOTPC64
:
2880 case elfcpp::R_X86_64_PLTOFF64
:
2881 // We need a GOT section.
2882 target
->got_section(symtab
, layout
);
2883 // For PLTOFF64, we also need a PLT entry (but only if the
2884 // symbol is not fully resolved).
2885 if (r_type
== elfcpp::R_X86_64_PLTOFF64
2886 && !gsym
->final_value_is_known())
2887 target
->make_plt_entry(symtab
, layout
, gsym
);
2890 case elfcpp::R_X86_64_COPY
:
2891 case elfcpp::R_X86_64_GLOB_DAT
:
2892 case elfcpp::R_X86_64_JUMP_SLOT
:
2893 case elfcpp::R_X86_64_RELATIVE
:
2894 case elfcpp::R_X86_64_IRELATIVE
:
2895 // These are outstanding tls relocs, which are unexpected when linking
2896 case elfcpp::R_X86_64_TPOFF64
:
2897 case elfcpp::R_X86_64_DTPMOD64
:
2898 case elfcpp::R_X86_64_TLSDESC
:
2899 gold_error(_("%s: unexpected reloc %u in object file"),
2900 object
->name().c_str(), r_type
);
2903 // These are initial tls relocs, which are expected for global()
2904 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
2905 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
2906 case elfcpp::R_X86_64_TLSDESC_CALL
:
2907 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
2908 case elfcpp::R_X86_64_DTPOFF32
:
2909 case elfcpp::R_X86_64_DTPOFF64
:
2910 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
2911 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
2913 const bool is_final
= gsym
->final_value_is_known();
2914 const tls::Tls_optimization optimized_type
2915 = Target_x86_64
<size
>::optimize_tls_reloc(is_final
, r_type
);
2918 case elfcpp::R_X86_64_TLSGD
: // General-dynamic
2919 if (optimized_type
== tls::TLSOPT_NONE
)
2921 // Create a pair of GOT entries for the module index and
2922 // dtv-relative offset.
2923 Output_data_got
<64, false>* got
2924 = target
->got_section(symtab
, layout
);
2925 got
->add_global_pair_with_rel(gsym
, GOT_TYPE_TLS_PAIR
,
2926 target
->rela_dyn_section(layout
),
2927 elfcpp::R_X86_64_DTPMOD64
,
2928 elfcpp::R_X86_64_DTPOFF64
);
2930 else if (optimized_type
== tls::TLSOPT_TO_IE
)
2932 // Create a GOT entry for the tp-relative offset.
2933 Output_data_got
<64, false>* got
2934 = target
->got_section(symtab
, layout
);
2935 got
->add_global_with_rel(gsym
, GOT_TYPE_TLS_OFFSET
,
2936 target
->rela_dyn_section(layout
),
2937 elfcpp::R_X86_64_TPOFF64
);
2939 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2940 unsupported_reloc_global(object
, r_type
, gsym
);
2943 case elfcpp::R_X86_64_GOTPC32_TLSDESC
:
2944 target
->define_tls_base_symbol(symtab
, layout
);
2945 if (optimized_type
== tls::TLSOPT_NONE
)
2947 // Create reserved PLT and GOT entries for the resolver.
2948 target
->reserve_tlsdesc_entries(symtab
, layout
);
2950 // Create a double GOT entry with an R_X86_64_TLSDESC
2951 // reloc. The R_X86_64_TLSDESC reloc is resolved
2952 // lazily, so the GOT entry needs to be in an area in
2953 // .got.plt, not .got. Call got_section to make sure
2954 // the section has been created.
2955 target
->got_section(symtab
, layout
);
2956 Output_data_got
<64, false>* got
= target
->got_tlsdesc_section();
2957 Reloc_section
* rt
= target
->rela_tlsdesc_section(layout
);
2958 got
->add_global_pair_with_rel(gsym
, GOT_TYPE_TLS_DESC
, rt
,
2959 elfcpp::R_X86_64_TLSDESC
, 0);
2961 else if (optimized_type
== tls::TLSOPT_TO_IE
)
2963 // Create a GOT entry for the tp-relative offset.
2964 Output_data_got
<64, false>* got
2965 = target
->got_section(symtab
, layout
);
2966 got
->add_global_with_rel(gsym
, GOT_TYPE_TLS_OFFSET
,
2967 target
->rela_dyn_section(layout
),
2968 elfcpp::R_X86_64_TPOFF64
);
2970 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2971 unsupported_reloc_global(object
, r_type
, gsym
);
2974 case elfcpp::R_X86_64_TLSDESC_CALL
:
2977 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
2978 if (optimized_type
== tls::TLSOPT_NONE
)
2980 // Create a GOT entry for the module index.
2981 target
->got_mod_index_entry(symtab
, layout
, object
);
2983 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2984 unsupported_reloc_global(object
, r_type
, gsym
);
2987 case elfcpp::R_X86_64_DTPOFF32
:
2988 case elfcpp::R_X86_64_DTPOFF64
:
2991 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
2992 layout
->set_has_static_tls();
2993 if (optimized_type
== tls::TLSOPT_NONE
)
2995 // Create a GOT entry for the tp-relative offset.
2996 Output_data_got
<64, false>* got
2997 = target
->got_section(symtab
, layout
);
2998 got
->add_global_with_rel(gsym
, GOT_TYPE_TLS_OFFSET
,
2999 target
->rela_dyn_section(layout
),
3000 elfcpp::R_X86_64_TPOFF64
);
3002 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
3003 unsupported_reloc_global(object
, r_type
, gsym
);
3006 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
3007 layout
->set_has_static_tls();
3008 if (parameters
->options().shared())
3009 unsupported_reloc_local(object
, r_type
);
3018 case elfcpp::R_X86_64_SIZE32
:
3019 case elfcpp::R_X86_64_SIZE64
:
3021 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
3022 object
->name().c_str(), r_type
,
3023 gsym
->demangled_name().c_str());
3030 Target_x86_64
<size
>::gc_process_relocs(Symbol_table
* symtab
,
3032 Sized_relobj_file
<size
, false>* object
,
3033 unsigned int data_shndx
,
3034 unsigned int sh_type
,
3035 const unsigned char* prelocs
,
3037 Output_section
* output_section
,
3038 bool needs_special_offset_handling
,
3039 size_t local_symbol_count
,
3040 const unsigned char* plocal_symbols
)
3043 if (sh_type
== elfcpp::SHT_REL
)
3048 gold::gc_process_relocs
<size
, false, Target_x86_64
<size
>, elfcpp::SHT_RELA
,
3049 typename Target_x86_64
<size
>::Scan
,
3050 typename Target_x86_64
<size
>::Relocatable_size_for_reloc
>(
3059 needs_special_offset_handling
,
3064 // Scan relocations for a section.
3068 Target_x86_64
<size
>::scan_relocs(Symbol_table
* symtab
,
3070 Sized_relobj_file
<size
, false>* object
,
3071 unsigned int data_shndx
,
3072 unsigned int sh_type
,
3073 const unsigned char* prelocs
,
3075 Output_section
* output_section
,
3076 bool needs_special_offset_handling
,
3077 size_t local_symbol_count
,
3078 const unsigned char* plocal_symbols
)
3080 if (sh_type
== elfcpp::SHT_REL
)
3082 gold_error(_("%s: unsupported REL reloc section"),
3083 object
->name().c_str());
3087 gold::scan_relocs
<size
, false, Target_x86_64
<size
>, elfcpp::SHT_RELA
,
3088 typename Target_x86_64
<size
>::Scan
>(
3097 needs_special_offset_handling
,
3102 // Finalize the sections.
3106 Target_x86_64
<size
>::do_finalize_sections(
3108 const Input_objects
*,
3109 Symbol_table
* symtab
)
3111 const Reloc_section
* rel_plt
= (this->plt_
== NULL
3113 : this->plt_
->rela_plt());
3114 layout
->add_target_dynamic_tags(false, this->got_plt_
, rel_plt
,
3115 this->rela_dyn_
, true, false);
3117 // Fill in some more dynamic tags.
3118 Output_data_dynamic
* const odyn
= layout
->dynamic_data();
3121 if (this->plt_
!= NULL
3122 && this->plt_
->output_section() != NULL
3123 && this->plt_
->has_tlsdesc_entry())
3125 unsigned int plt_offset
= this->plt_
->get_tlsdesc_plt_offset();
3126 unsigned int got_offset
= this->plt_
->get_tlsdesc_got_offset();
3127 this->got_
->finalize_data_size();
3128 odyn
->add_section_plus_offset(elfcpp::DT_TLSDESC_PLT
,
3129 this->plt_
, plt_offset
);
3130 odyn
->add_section_plus_offset(elfcpp::DT_TLSDESC_GOT
,
3131 this->got_
, got_offset
);
3135 // Emit any relocs we saved in an attempt to avoid generating COPY
3137 if (this->copy_relocs_
.any_saved_relocs())
3138 this->copy_relocs_
.emit(this->rela_dyn_section(layout
));
3140 // Set the size of the _GLOBAL_OFFSET_TABLE_ symbol to the size of
3141 // the .got.plt section.
3142 Symbol
* sym
= this->global_offset_table_
;
3145 uint64_t data_size
= this->got_plt_
->current_data_size();
3146 symtab
->get_sized_symbol
<size
>(sym
)->set_symsize(data_size
);
3149 if (parameters
->doing_static_link()
3150 && (this->plt_
== NULL
|| !this->plt_
->has_irelative_section()))
3152 // If linking statically, make sure that the __rela_iplt symbols
3153 // were defined if necessary, even if we didn't create a PLT.
3154 static const Define_symbol_in_segment syms
[] =
3157 "__rela_iplt_start", // name
3158 elfcpp::PT_LOAD
, // segment_type
3159 elfcpp::PF_W
, // segment_flags_set
3160 elfcpp::PF(0), // segment_flags_clear
3163 elfcpp::STT_NOTYPE
, // type
3164 elfcpp::STB_GLOBAL
, // binding
3165 elfcpp::STV_HIDDEN
, // visibility
3167 Symbol::SEGMENT_START
, // offset_from_base
3171 "__rela_iplt_end", // name
3172 elfcpp::PT_LOAD
, // segment_type
3173 elfcpp::PF_W
, // segment_flags_set
3174 elfcpp::PF(0), // segment_flags_clear
3177 elfcpp::STT_NOTYPE
, // type
3178 elfcpp::STB_GLOBAL
, // binding
3179 elfcpp::STV_HIDDEN
, // visibility
3181 Symbol::SEGMENT_START
, // offset_from_base
3186 symtab
->define_symbols(layout
, 2, syms
,
3187 layout
->script_options()->saw_sections_clause());
3191 // Perform a relocation.
3195 Target_x86_64
<size
>::Relocate::relocate(
3196 const Relocate_info
<size
, false>* relinfo
,
3197 Target_x86_64
<size
>* target
,
3200 const elfcpp::Rela
<size
, false>& rela
,
3201 unsigned int r_type
,
3202 const Sized_symbol
<size
>* gsym
,
3203 const Symbol_value
<size
>* psymval
,
3204 unsigned char* view
,
3205 typename
elfcpp::Elf_types
<size
>::Elf_Addr address
,
3206 section_size_type view_size
)
3208 if (this->skip_call_tls_get_addr_
)
3210 if ((r_type
!= elfcpp::R_X86_64_PLT32
3211 && r_type
!= elfcpp::R_X86_64_PC32
)
3213 || strcmp(gsym
->name(), "__tls_get_addr") != 0)
3215 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
3216 _("missing expected TLS relocation"));
3220 this->skip_call_tls_get_addr_
= false;
3225 const Sized_relobj_file
<size
, false>* object
= relinfo
->object
;
3227 // Pick the value to use for symbols defined in the PLT.
3228 Symbol_value
<size
> symval
;
3230 && gsym
->use_plt_offset(Scan::get_reference_flags(r_type
)))
3232 symval
.set_output_value(target
->plt_address_for_global(gsym
)
3233 + gsym
->plt_offset());
3236 else if (gsym
== NULL
&& psymval
->is_ifunc_symbol())
3238 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(rela
.get_r_info());
3239 if (object
->local_has_plt_offset(r_sym
))
3241 symval
.set_output_value(target
->plt_address_for_local(object
, r_sym
)
3242 + object
->local_plt_offset(r_sym
));
3247 const elfcpp::Elf_Xword addend
= rela
.get_r_addend();
3249 // Get the GOT offset if needed.
3250 // The GOT pointer points to the end of the GOT section.
3251 // We need to subtract the size of the GOT section to get
3252 // the actual offset to use in the relocation.
3253 bool have_got_offset
= false;
3254 unsigned int got_offset
= 0;
3257 case elfcpp::R_X86_64_GOT32
:
3258 case elfcpp::R_X86_64_GOT64
:
3259 case elfcpp::R_X86_64_GOTPLT64
:
3260 case elfcpp::R_X86_64_GOTPCREL
:
3261 case elfcpp::R_X86_64_GOTPCREL64
:
3264 gold_assert(gsym
->has_got_offset(GOT_TYPE_STANDARD
));
3265 got_offset
= gsym
->got_offset(GOT_TYPE_STANDARD
) - target
->got_size();
3269 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(rela
.get_r_info());
3270 gold_assert(object
->local_has_got_offset(r_sym
, GOT_TYPE_STANDARD
));
3271 got_offset
= (object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
)
3272 - target
->got_size());
3274 have_got_offset
= true;
3283 case elfcpp::R_X86_64_NONE
:
3284 case elfcpp::R_X86_64_GNU_VTINHERIT
:
3285 case elfcpp::R_X86_64_GNU_VTENTRY
:
3288 case elfcpp::R_X86_64_64
:
3289 Relocate_functions
<size
, false>::rela64(view
, object
, psymval
, addend
);
3292 case elfcpp::R_X86_64_PC64
:
3293 Relocate_functions
<size
, false>::pcrela64(view
, object
, psymval
, addend
,
3297 case elfcpp::R_X86_64_32
:
3298 // FIXME: we need to verify that value + addend fits into 32 bits:
3299 // uint64_t x = value + addend;
3300 // x == static_cast<uint64_t>(static_cast<uint32_t>(x))
3301 // Likewise for other <=32-bit relocations (but see R_X86_64_32S).
3302 Relocate_functions
<size
, false>::rela32(view
, object
, psymval
, addend
);
3305 case elfcpp::R_X86_64_32S
:
3306 // FIXME: we need to verify that value + addend fits into 32 bits:
3307 // int64_t x = value + addend; // note this quantity is signed!
3308 // x == static_cast<int64_t>(static_cast<int32_t>(x))
3309 Relocate_functions
<size
, false>::rela32(view
, object
, psymval
, addend
);
3312 case elfcpp::R_X86_64_PC32
:
3313 Relocate_functions
<size
, false>::pcrela32(view
, object
, psymval
, addend
,
3317 case elfcpp::R_X86_64_16
:
3318 Relocate_functions
<size
, false>::rela16(view
, object
, psymval
, addend
);
3321 case elfcpp::R_X86_64_PC16
:
3322 Relocate_functions
<size
, false>::pcrela16(view
, object
, psymval
, addend
,
3326 case elfcpp::R_X86_64_8
:
3327 Relocate_functions
<size
, false>::rela8(view
, object
, psymval
, addend
);
3330 case elfcpp::R_X86_64_PC8
:
3331 Relocate_functions
<size
, false>::pcrela8(view
, object
, psymval
, addend
,
3335 case elfcpp::R_X86_64_PLT32
:
3336 gold_assert(gsym
== NULL
3337 || gsym
->has_plt_offset()
3338 || gsym
->final_value_is_known()
3339 || (gsym
->is_defined()
3340 && !gsym
->is_from_dynobj()
3341 && !gsym
->is_preemptible()));
3342 // Note: while this code looks the same as for R_X86_64_PC32, it
3343 // behaves differently because psymval was set to point to
3344 // the PLT entry, rather than the symbol, in Scan::global().
3345 Relocate_functions
<size
, false>::pcrela32(view
, object
, psymval
, addend
,
3349 case elfcpp::R_X86_64_PLTOFF64
:
3352 gold_assert(gsym
->has_plt_offset()
3353 || gsym
->final_value_is_known());
3354 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
;
3355 got_address
= target
->got_section(NULL
, NULL
)->address();
3356 Relocate_functions
<size
, false>::rela64(view
, object
, psymval
,
3357 addend
- got_address
);
3360 case elfcpp::R_X86_64_GOT32
:
3361 gold_assert(have_got_offset
);
3362 Relocate_functions
<size
, false>::rela32(view
, got_offset
, addend
);
3365 case elfcpp::R_X86_64_GOTPC32
:
3368 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
;
3369 value
= target
->got_plt_section()->address();
3370 Relocate_functions
<size
, false>::pcrela32(view
, value
, addend
, address
);
3374 case elfcpp::R_X86_64_GOT64
:
3375 // The ABI doc says "Like GOT64, but indicates a PLT entry is needed."
3376 // Since we always add a PLT entry, this is equivalent.
3377 case elfcpp::R_X86_64_GOTPLT64
:
3378 gold_assert(have_got_offset
);
3379 Relocate_functions
<size
, false>::rela64(view
, got_offset
, addend
);
3382 case elfcpp::R_X86_64_GOTPC64
:
3385 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
;
3386 value
= target
->got_plt_section()->address();
3387 Relocate_functions
<size
, false>::pcrela64(view
, value
, addend
, address
);
3391 case elfcpp::R_X86_64_GOTOFF64
:
3393 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
;
3394 value
= (psymval
->value(object
, 0)
3395 - target
->got_plt_section()->address());
3396 Relocate_functions
<size
, false>::rela64(view
, value
, addend
);
3400 case elfcpp::R_X86_64_GOTPCREL
:
3402 gold_assert(have_got_offset
);
3403 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
;
3404 value
= target
->got_plt_section()->address() + got_offset
;
3405 Relocate_functions
<size
, false>::pcrela32(view
, value
, addend
, address
);
3409 case elfcpp::R_X86_64_GOTPCREL64
:
3411 gold_assert(have_got_offset
);
3412 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
;
3413 value
= target
->got_plt_section()->address() + got_offset
;
3414 Relocate_functions
<size
, false>::pcrela64(view
, value
, addend
, address
);
3418 case elfcpp::R_X86_64_COPY
:
3419 case elfcpp::R_X86_64_GLOB_DAT
:
3420 case elfcpp::R_X86_64_JUMP_SLOT
:
3421 case elfcpp::R_X86_64_RELATIVE
:
3422 case elfcpp::R_X86_64_IRELATIVE
:
3423 // These are outstanding tls relocs, which are unexpected when linking
3424 case elfcpp::R_X86_64_TPOFF64
:
3425 case elfcpp::R_X86_64_DTPMOD64
:
3426 case elfcpp::R_X86_64_TLSDESC
:
3427 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
3428 _("unexpected reloc %u in object file"),
3432 // These are initial tls relocs, which are expected when linking
3433 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
3434 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
3435 case elfcpp::R_X86_64_TLSDESC_CALL
:
3436 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
3437 case elfcpp::R_X86_64_DTPOFF32
:
3438 case elfcpp::R_X86_64_DTPOFF64
:
3439 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
3440 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
3441 this->relocate_tls(relinfo
, target
, relnum
, rela
, r_type
, gsym
, psymval
,
3442 view
, address
, view_size
);
3445 case elfcpp::R_X86_64_SIZE32
:
3446 case elfcpp::R_X86_64_SIZE64
:
3448 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
3449 _("unsupported reloc %u"),
3457 // Perform a TLS relocation.
3461 Target_x86_64
<size
>::Relocate::relocate_tls(
3462 const Relocate_info
<size
, false>* relinfo
,
3463 Target_x86_64
<size
>* target
,
3465 const elfcpp::Rela
<size
, false>& rela
,
3466 unsigned int r_type
,
3467 const Sized_symbol
<size
>* gsym
,
3468 const Symbol_value
<size
>* psymval
,
3469 unsigned char* view
,
3470 typename
elfcpp::Elf_types
<size
>::Elf_Addr address
,
3471 section_size_type view_size
)
3473 Output_segment
* tls_segment
= relinfo
->layout
->tls_segment();
3475 const Sized_relobj_file
<size
, false>* object
= relinfo
->object
;
3476 const elfcpp::Elf_Xword addend
= rela
.get_r_addend();
3477 elfcpp::Shdr
<size
, false> data_shdr(relinfo
->data_shdr
);
3478 bool is_executable
= (data_shdr
.get_sh_flags() & elfcpp::SHF_EXECINSTR
) != 0;
3480 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
= psymval
->value(relinfo
->object
, 0);
3482 const bool is_final
= (gsym
== NULL
3483 ? !parameters
->options().shared()
3484 : gsym
->final_value_is_known());
3485 tls::Tls_optimization optimized_type
3486 = Target_x86_64
<size
>::optimize_tls_reloc(is_final
, r_type
);
3489 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
3490 if (!is_executable
&& optimized_type
== tls::TLSOPT_TO_LE
)
3492 // If this code sequence is used in a non-executable section,
3493 // we will not optimize the R_X86_64_DTPOFF32/64 relocation,
3494 // on the assumption that it's being used by itself in a debug
3495 // section. Therefore, in the unlikely event that the code
3496 // sequence appears in a non-executable section, we simply
3497 // leave it unoptimized.
3498 optimized_type
= tls::TLSOPT_NONE
;
3500 if (optimized_type
== tls::TLSOPT_TO_LE
)
3502 if (tls_segment
== NULL
)
3504 gold_assert(parameters
->errors()->error_count() > 0
3505 || issue_undefined_symbol_error(gsym
));
3508 this->tls_gd_to_le(relinfo
, relnum
, tls_segment
,
3509 rela
, r_type
, value
, view
,
3515 unsigned int got_type
= (optimized_type
== tls::TLSOPT_TO_IE
3516 ? GOT_TYPE_TLS_OFFSET
3517 : GOT_TYPE_TLS_PAIR
);
3518 unsigned int got_offset
;
3521 gold_assert(gsym
->has_got_offset(got_type
));
3522 got_offset
= gsym
->got_offset(got_type
) - target
->got_size();
3526 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(rela
.get_r_info());
3527 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
3528 got_offset
= (object
->local_got_offset(r_sym
, got_type
)
3529 - target
->got_size());
3531 if (optimized_type
== tls::TLSOPT_TO_IE
)
3533 value
= target
->got_plt_section()->address() + got_offset
;
3534 this->tls_gd_to_ie(relinfo
, relnum
, tls_segment
, rela
, r_type
,
3535 value
, view
, address
, view_size
);
3538 else if (optimized_type
== tls::TLSOPT_NONE
)
3540 // Relocate the field with the offset of the pair of GOT
3542 value
= target
->got_plt_section()->address() + got_offset
;
3543 Relocate_functions
<size
, false>::pcrela32(view
, value
, addend
,
3548 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
3549 _("unsupported reloc %u"), r_type
);
3552 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
3553 case elfcpp::R_X86_64_TLSDESC_CALL
:
3554 if (!is_executable
&& optimized_type
== tls::TLSOPT_TO_LE
)
3556 // See above comment for R_X86_64_TLSGD.
3557 optimized_type
= tls::TLSOPT_NONE
;
3559 if (optimized_type
== tls::TLSOPT_TO_LE
)
3561 if (tls_segment
== NULL
)
3563 gold_assert(parameters
->errors()->error_count() > 0
3564 || issue_undefined_symbol_error(gsym
));
3567 this->tls_desc_gd_to_le(relinfo
, relnum
, tls_segment
,
3568 rela
, r_type
, value
, view
,
3574 unsigned int got_type
= (optimized_type
== tls::TLSOPT_TO_IE
3575 ? GOT_TYPE_TLS_OFFSET
3576 : GOT_TYPE_TLS_DESC
);
3577 unsigned int got_offset
= 0;
3578 if (r_type
== elfcpp::R_X86_64_GOTPC32_TLSDESC
3579 && optimized_type
== tls::TLSOPT_NONE
)
3581 // We created GOT entries in the .got.tlsdesc portion of
3582 // the .got.plt section, but the offset stored in the
3583 // symbol is the offset within .got.tlsdesc.
3584 got_offset
= (target
->got_size()
3585 + target
->got_plt_section()->data_size());
3589 gold_assert(gsym
->has_got_offset(got_type
));
3590 got_offset
+= gsym
->got_offset(got_type
) - target
->got_size();
3594 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(rela
.get_r_info());
3595 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
3596 got_offset
+= (object
->local_got_offset(r_sym
, got_type
)
3597 - target
->got_size());
3599 if (optimized_type
== tls::TLSOPT_TO_IE
)
3601 if (tls_segment
== NULL
)
3603 gold_assert(parameters
->errors()->error_count() > 0
3604 || issue_undefined_symbol_error(gsym
));
3607 value
= target
->got_plt_section()->address() + got_offset
;
3608 this->tls_desc_gd_to_ie(relinfo
, relnum
, tls_segment
,
3609 rela
, r_type
, value
, view
, address
,
3613 else if (optimized_type
== tls::TLSOPT_NONE
)
3615 if (r_type
== elfcpp::R_X86_64_GOTPC32_TLSDESC
)
3617 // Relocate the field with the offset of the pair of GOT
3619 value
= target
->got_plt_section()->address() + got_offset
;
3620 Relocate_functions
<size
, false>::pcrela32(view
, value
, addend
,
3626 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
3627 _("unsupported reloc %u"), r_type
);
3630 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
3631 if (!is_executable
&& optimized_type
== tls::TLSOPT_TO_LE
)
3633 // See above comment for R_X86_64_TLSGD.
3634 optimized_type
= tls::TLSOPT_NONE
;
3636 if (optimized_type
== tls::TLSOPT_TO_LE
)
3638 if (tls_segment
== NULL
)
3640 gold_assert(parameters
->errors()->error_count() > 0
3641 || issue_undefined_symbol_error(gsym
));
3644 this->tls_ld_to_le(relinfo
, relnum
, tls_segment
, rela
, r_type
,
3645 value
, view
, view_size
);
3648 else if (optimized_type
== tls::TLSOPT_NONE
)
3650 // Relocate the field with the offset of the GOT entry for
3651 // the module index.
3652 unsigned int got_offset
;
3653 got_offset
= (target
->got_mod_index_entry(NULL
, NULL
, NULL
)
3654 - target
->got_size());
3655 value
= target
->got_plt_section()->address() + got_offset
;
3656 Relocate_functions
<size
, false>::pcrela32(view
, value
, addend
,
3660 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
3661 _("unsupported reloc %u"), r_type
);
3664 case elfcpp::R_X86_64_DTPOFF32
:
3665 // This relocation type is used in debugging information.
3666 // In that case we need to not optimize the value. If the
3667 // section is not executable, then we assume we should not
3668 // optimize this reloc. See comments above for R_X86_64_TLSGD,
3669 // R_X86_64_GOTPC32_TLSDESC, R_X86_64_TLSDESC_CALL, and
3671 if (optimized_type
== tls::TLSOPT_TO_LE
&& is_executable
)
3673 if (tls_segment
== NULL
)
3675 gold_assert(parameters
->errors()->error_count() > 0
3676 || issue_undefined_symbol_error(gsym
));
3679 value
-= tls_segment
->memsz();
3681 Relocate_functions
<size
, false>::rela32(view
, value
, addend
);
3684 case elfcpp::R_X86_64_DTPOFF64
:
3685 // See R_X86_64_DTPOFF32, just above, for why we check for is_executable.
3686 if (optimized_type
== tls::TLSOPT_TO_LE
&& is_executable
)
3688 if (tls_segment
== NULL
)
3690 gold_assert(parameters
->errors()->error_count() > 0
3691 || issue_undefined_symbol_error(gsym
));
3694 value
-= tls_segment
->memsz();
3696 Relocate_functions
<size
, false>::rela64(view
, value
, addend
);
3699 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
3700 if (optimized_type
== tls::TLSOPT_TO_LE
)
3702 if (tls_segment
== NULL
)
3704 gold_assert(parameters
->errors()->error_count() > 0
3705 || issue_undefined_symbol_error(gsym
));
3708 Target_x86_64
<size
>::Relocate::tls_ie_to_le(relinfo
, relnum
,
3710 r_type
, value
, view
,
3714 else if (optimized_type
== tls::TLSOPT_NONE
)
3716 // Relocate the field with the offset of the GOT entry for
3717 // the tp-relative offset of the symbol.
3718 unsigned int got_offset
;
3721 gold_assert(gsym
->has_got_offset(GOT_TYPE_TLS_OFFSET
));
3722 got_offset
= (gsym
->got_offset(GOT_TYPE_TLS_OFFSET
)
3723 - target
->got_size());
3727 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(rela
.get_r_info());
3728 gold_assert(object
->local_has_got_offset(r_sym
,
3729 GOT_TYPE_TLS_OFFSET
));
3730 got_offset
= (object
->local_got_offset(r_sym
, GOT_TYPE_TLS_OFFSET
)
3731 - target
->got_size());
3733 value
= target
->got_plt_section()->address() + got_offset
;
3734 Relocate_functions
<size
, false>::pcrela32(view
, value
, addend
,
3738 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
3739 _("unsupported reloc type %u"),
3743 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
3744 if (tls_segment
== NULL
)
3746 gold_assert(parameters
->errors()->error_count() > 0
3747 || issue_undefined_symbol_error(gsym
));
3750 value
-= tls_segment
->memsz();
3751 Relocate_functions
<size
, false>::rela32(view
, value
, addend
);
3756 // Do a relocation in which we convert a TLS General-Dynamic to an
3761 Target_x86_64
<size
>::Relocate::tls_gd_to_ie(
3762 const Relocate_info
<size
, false>* relinfo
,
3765 const elfcpp::Rela
<size
, false>& rela
,
3767 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
3768 unsigned char* view
,
3769 typename
elfcpp::Elf_types
<size
>::Elf_Addr address
,
3770 section_size_type view_size
)
3773 // .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
3774 // .word 0x6666; rex64; call __tls_get_addr
3775 // ==> movq %fs:0,%rax; addq x@gottpoff(%rip),%rax
3777 // leaq foo@tlsgd(%rip),%rdi;
3778 // .word 0x6666; rex64; call __tls_get_addr
3779 // ==> movl %fs:0,%eax; addq x@gottpoff(%rip),%rax
3781 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 12);
3782 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
3783 (memcmp(view
+ 4, "\x66\x66\x48\xe8", 4) == 0));
3787 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
,
3789 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
3790 (memcmp(view
- 4, "\x66\x48\x8d\x3d", 4) == 0));
3791 memcpy(view
- 4, "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x03\x05\0\0\0\0",
3796 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
,
3798 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
3799 (memcmp(view
- 3, "\x48\x8d\x3d", 3) == 0));
3800 memcpy(view
- 3, "\x64\x8b\x04\x25\0\0\0\0\x48\x03\x05\0\0\0\0",
3804 const elfcpp::Elf_Xword addend
= rela
.get_r_addend();
3805 Relocate_functions
<size
, false>::pcrela32(view
+ 8, value
, addend
- 8,
3808 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3810 this->skip_call_tls_get_addr_
= true;
3813 // Do a relocation in which we convert a TLS General-Dynamic to a
3818 Target_x86_64
<size
>::Relocate::tls_gd_to_le(
3819 const Relocate_info
<size
, false>* relinfo
,
3821 Output_segment
* tls_segment
,
3822 const elfcpp::Rela
<size
, false>& rela
,
3824 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
3825 unsigned char* view
,
3826 section_size_type view_size
)
3829 // .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
3830 // .word 0x6666; rex64; call __tls_get_addr
3831 // ==> movq %fs:0,%rax; leaq x@tpoff(%rax),%rax
3833 // leaq foo@tlsgd(%rip),%rdi;
3834 // .word 0x6666; rex64; call __tls_get_addr
3835 // ==> movl %fs:0,%eax; leaq x@tpoff(%rax),%rax
3837 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 12);
3838 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
3839 (memcmp(view
+ 4, "\x66\x66\x48\xe8", 4) == 0));
3843 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
,
3845 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
3846 (memcmp(view
- 4, "\x66\x48\x8d\x3d", 4) == 0));
3847 memcpy(view
- 4, "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0\0",
3852 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
,
3854 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
3855 (memcmp(view
- 3, "\x48\x8d\x3d", 3) == 0));
3857 memcpy(view
- 3, "\x64\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0\0",
3861 value
-= tls_segment
->memsz();
3862 Relocate_functions
<size
, false>::rela32(view
+ 8, value
, 0);
3864 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3866 this->skip_call_tls_get_addr_
= true;
3869 // Do a TLSDESC-style General-Dynamic to Initial-Exec transition.
3873 Target_x86_64
<size
>::Relocate::tls_desc_gd_to_ie(
3874 const Relocate_info
<size
, false>* relinfo
,
3877 const elfcpp::Rela
<size
, false>& rela
,
3878 unsigned int r_type
,
3879 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
3880 unsigned char* view
,
3881 typename
elfcpp::Elf_types
<size
>::Elf_Addr address
,
3882 section_size_type view_size
)
3884 if (r_type
== elfcpp::R_X86_64_GOTPC32_TLSDESC
)
3886 // leaq foo@tlsdesc(%rip), %rax
3887 // ==> movq foo@gottpoff(%rip), %rax
3888 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -3);
3889 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 4);
3890 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
3891 view
[-3] == 0x48 && view
[-2] == 0x8d && view
[-1] == 0x05);
3893 const elfcpp::Elf_Xword addend
= rela
.get_r_addend();
3894 Relocate_functions
<size
, false>::pcrela32(view
, value
, addend
, address
);
3898 // call *foo@tlscall(%rax)
3900 gold_assert(r_type
== elfcpp::R_X86_64_TLSDESC_CALL
);
3901 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 2);
3902 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
3903 view
[0] == 0xff && view
[1] == 0x10);
3909 // Do a TLSDESC-style General-Dynamic to Local-Exec transition.
3913 Target_x86_64
<size
>::Relocate::tls_desc_gd_to_le(
3914 const Relocate_info
<size
, false>* relinfo
,
3916 Output_segment
* tls_segment
,
3917 const elfcpp::Rela
<size
, false>& rela
,
3918 unsigned int r_type
,
3919 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
3920 unsigned char* view
,
3921 section_size_type view_size
)
3923 if (r_type
== elfcpp::R_X86_64_GOTPC32_TLSDESC
)
3925 // leaq foo@tlsdesc(%rip), %rax
3926 // ==> movq foo@tpoff, %rax
3927 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -3);
3928 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 4);
3929 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
3930 view
[-3] == 0x48 && view
[-2] == 0x8d && view
[-1] == 0x05);
3933 value
-= tls_segment
->memsz();
3934 Relocate_functions
<size
, false>::rela32(view
, value
, 0);
3938 // call *foo@tlscall(%rax)
3940 gold_assert(r_type
== elfcpp::R_X86_64_TLSDESC_CALL
);
3941 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 2);
3942 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
3943 view
[0] == 0xff && view
[1] == 0x10);
3951 Target_x86_64
<size
>::Relocate::tls_ld_to_le(
3952 const Relocate_info
<size
, false>* relinfo
,
3955 const elfcpp::Rela
<size
, false>& rela
,
3957 typename
elfcpp::Elf_types
<size
>::Elf_Addr
,
3958 unsigned char* view
,
3959 section_size_type view_size
)
3961 // leaq foo@tlsld(%rip),%rdi; call __tls_get_addr@plt;
3962 // ... leq foo@dtpoff(%rax),%reg
3963 // ==> .word 0x6666; .byte 0x66; movq %fs:0,%rax ... leaq x@tpoff(%rax),%rdx
3965 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -3);
3966 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 9);
3968 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
3969 view
[-3] == 0x48 && view
[-2] == 0x8d && view
[-1] == 0x3d);
3971 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(), view
[4] == 0xe8);
3973 memcpy(view
- 3, "\x66\x66\x66\x64\x48\x8b\x04\x25\0\0\0\0", 12);
3975 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3977 this->skip_call_tls_get_addr_
= true;
3980 // Do a relocation in which we convert a TLS Initial-Exec to a
3985 Target_x86_64
<size
>::Relocate::tls_ie_to_le(
3986 const Relocate_info
<size
, false>* relinfo
,
3988 Output_segment
* tls_segment
,
3989 const elfcpp::Rela
<size
, false>& rela
,
3991 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
3992 unsigned char* view
,
3993 section_size_type view_size
)
3995 // We need to examine the opcodes to figure out which instruction we
3998 // movq foo@gottpoff(%rip),%reg ==> movq $YY,%reg
3999 // addq foo@gottpoff(%rip),%reg ==> addq $YY,%reg
4001 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -3);
4002 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 4);
4004 unsigned char op1
= view
[-3];
4005 unsigned char op2
= view
[-2];
4006 unsigned char op3
= view
[-1];
4007 unsigned char reg
= op3
>> 3;
4015 view
[-1] = 0xc0 | reg
;
4019 // Special handling for %rsp.
4023 view
[-1] = 0xc0 | reg
;
4031 view
[-1] = 0x80 | reg
| (reg
<< 3);
4034 value
-= tls_segment
->memsz();
4035 Relocate_functions
<size
, false>::rela32(view
, value
, 0);
4038 // Relocate section data.
4042 Target_x86_64
<size
>::relocate_section(
4043 const Relocate_info
<size
, false>* relinfo
,
4044 unsigned int sh_type
,
4045 const unsigned char* prelocs
,
4047 Output_section
* output_section
,
4048 bool needs_special_offset_handling
,
4049 unsigned char* view
,
4050 typename
elfcpp::Elf_types
<size
>::Elf_Addr address
,
4051 section_size_type view_size
,
4052 const Reloc_symbol_changes
* reloc_symbol_changes
)
4054 gold_assert(sh_type
== elfcpp::SHT_RELA
);
4056 gold::relocate_section
<size
, false, Target_x86_64
<size
>, elfcpp::SHT_RELA
,
4057 typename Target_x86_64
<size
>::Relocate
>(
4063 needs_special_offset_handling
,
4067 reloc_symbol_changes
);
4070 // Apply an incremental relocation. Incremental relocations always refer
4071 // to global symbols.
4075 Target_x86_64
<size
>::apply_relocation(
4076 const Relocate_info
<size
, false>* relinfo
,
4077 typename
elfcpp::Elf_types
<size
>::Elf_Addr r_offset
,
4078 unsigned int r_type
,
4079 typename
elfcpp::Elf_types
<size
>::Elf_Swxword r_addend
,
4081 unsigned char* view
,
4082 typename
elfcpp::Elf_types
<size
>::Elf_Addr address
,
4083 section_size_type view_size
)
4085 gold::apply_relocation
<size
, false, Target_x86_64
<size
>,
4086 typename Target_x86_64
<size
>::Relocate
>(
4098 // Return the size of a relocation while scanning during a relocatable
4103 Target_x86_64
<size
>::Relocatable_size_for_reloc::get_size_for_reloc(
4104 unsigned int r_type
,
4109 case elfcpp::R_X86_64_NONE
:
4110 case elfcpp::R_X86_64_GNU_VTINHERIT
:
4111 case elfcpp::R_X86_64_GNU_VTENTRY
:
4112 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
4113 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
4114 case elfcpp::R_X86_64_TLSDESC_CALL
:
4115 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
4116 case elfcpp::R_X86_64_DTPOFF32
:
4117 case elfcpp::R_X86_64_DTPOFF64
:
4118 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
4119 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
4122 case elfcpp::R_X86_64_64
:
4123 case elfcpp::R_X86_64_PC64
:
4124 case elfcpp::R_X86_64_GOTOFF64
:
4125 case elfcpp::R_X86_64_GOTPC64
:
4126 case elfcpp::R_X86_64_PLTOFF64
:
4127 case elfcpp::R_X86_64_GOT64
:
4128 case elfcpp::R_X86_64_GOTPCREL64
:
4129 case elfcpp::R_X86_64_GOTPCREL
:
4130 case elfcpp::R_X86_64_GOTPLT64
:
4133 case elfcpp::R_X86_64_32
:
4134 case elfcpp::R_X86_64_32S
:
4135 case elfcpp::R_X86_64_PC32
:
4136 case elfcpp::R_X86_64_PLT32
:
4137 case elfcpp::R_X86_64_GOTPC32
:
4138 case elfcpp::R_X86_64_GOT32
:
4141 case elfcpp::R_X86_64_16
:
4142 case elfcpp::R_X86_64_PC16
:
4145 case elfcpp::R_X86_64_8
:
4146 case elfcpp::R_X86_64_PC8
:
4149 case elfcpp::R_X86_64_COPY
:
4150 case elfcpp::R_X86_64_GLOB_DAT
:
4151 case elfcpp::R_X86_64_JUMP_SLOT
:
4152 case elfcpp::R_X86_64_RELATIVE
:
4153 case elfcpp::R_X86_64_IRELATIVE
:
4154 // These are outstanding tls relocs, which are unexpected when linking
4155 case elfcpp::R_X86_64_TPOFF64
:
4156 case elfcpp::R_X86_64_DTPMOD64
:
4157 case elfcpp::R_X86_64_TLSDESC
:
4158 object
->error(_("unexpected reloc %u in object file"), r_type
);
4161 case elfcpp::R_X86_64_SIZE32
:
4162 case elfcpp::R_X86_64_SIZE64
:
4164 object
->error(_("unsupported reloc %u against local symbol"), r_type
);
4169 // Scan the relocs during a relocatable link.
4173 Target_x86_64
<size
>::scan_relocatable_relocs(
4174 Symbol_table
* symtab
,
4176 Sized_relobj_file
<size
, false>* object
,
4177 unsigned int data_shndx
,
4178 unsigned int sh_type
,
4179 const unsigned char* prelocs
,
4181 Output_section
* output_section
,
4182 bool needs_special_offset_handling
,
4183 size_t local_symbol_count
,
4184 const unsigned char* plocal_symbols
,
4185 Relocatable_relocs
* rr
)
4187 gold_assert(sh_type
== elfcpp::SHT_RELA
);
4189 typedef gold::Default_scan_relocatable_relocs
<elfcpp::SHT_RELA
,
4190 Relocatable_size_for_reloc
> Scan_relocatable_relocs
;
4192 gold::scan_relocatable_relocs
<size
, false, elfcpp::SHT_RELA
,
4193 Scan_relocatable_relocs
>(
4201 needs_special_offset_handling
,
4207 // Relocate a section during a relocatable link.
4211 Target_x86_64
<size
>::relocate_for_relocatable(
4212 const Relocate_info
<size
, false>* relinfo
,
4213 unsigned int sh_type
,
4214 const unsigned char* prelocs
,
4216 Output_section
* output_section
,
4217 off_t offset_in_output_section
,
4218 const Relocatable_relocs
* rr
,
4219 unsigned char* view
,
4220 typename
elfcpp::Elf_types
<size
>::Elf_Addr view_address
,
4221 section_size_type view_size
,
4222 unsigned char* reloc_view
,
4223 section_size_type reloc_view_size
)
4225 gold_assert(sh_type
== elfcpp::SHT_RELA
);
4227 gold::relocate_for_relocatable
<size
, false, elfcpp::SHT_RELA
>(
4232 offset_in_output_section
,
4241 // Return the value to use for a dynamic which requires special
4242 // treatment. This is how we support equality comparisons of function
4243 // pointers across shared library boundaries, as described in the
4244 // processor specific ABI supplement.
4248 Target_x86_64
<size
>::do_dynsym_value(const Symbol
* gsym
) const
4250 gold_assert(gsym
->is_from_dynobj() && gsym
->has_plt_offset());
4251 return this->plt_address_for_global(gsym
) + gsym
->plt_offset();
4254 // Return a string used to fill a code section with nops to take up
4255 // the specified length.
4259 Target_x86_64
<size
>::do_code_fill(section_size_type length
) const
4263 // Build a jmpq instruction to skip over the bytes.
4264 unsigned char jmp
[5];
4266 elfcpp::Swap_unaligned
<32, false>::writeval(jmp
+ 1, length
- 5);
4267 return (std::string(reinterpret_cast<char*>(&jmp
[0]), 5)
4268 + std::string(length
- 5, static_cast<char>(0x90)));
4271 // Nop sequences of various lengths.
4272 const char nop1
[1] = { '\x90' }; // nop
4273 const char nop2
[2] = { '\x66', '\x90' }; // xchg %ax %ax
4274 const char nop3
[3] = { '\x0f', '\x1f', '\x00' }; // nop (%rax)
4275 const char nop4
[4] = { '\x0f', '\x1f', '\x40', // nop 0(%rax)
4277 const char nop5
[5] = { '\x0f', '\x1f', '\x44', // nop 0(%rax,%rax,1)
4279 const char nop6
[6] = { '\x66', '\x0f', '\x1f', // nopw 0(%rax,%rax,1)
4280 '\x44', '\x00', '\x00' };
4281 const char nop7
[7] = { '\x0f', '\x1f', '\x80', // nopl 0L(%rax)
4282 '\x00', '\x00', '\x00',
4284 const char nop8
[8] = { '\x0f', '\x1f', '\x84', // nopl 0L(%rax,%rax,1)
4285 '\x00', '\x00', '\x00',
4287 const char nop9
[9] = { '\x66', '\x0f', '\x1f', // nopw 0L(%rax,%rax,1)
4288 '\x84', '\x00', '\x00',
4289 '\x00', '\x00', '\x00' };
4290 const char nop10
[10] = { '\x66', '\x2e', '\x0f', // nopw %cs:0L(%rax,%rax,1)
4291 '\x1f', '\x84', '\x00',
4292 '\x00', '\x00', '\x00',
4294 const char nop11
[11] = { '\x66', '\x66', '\x2e', // data16
4295 '\x0f', '\x1f', '\x84', // nopw %cs:0L(%rax,%rax,1)
4296 '\x00', '\x00', '\x00',
4298 const char nop12
[12] = { '\x66', '\x66', '\x66', // data16; data16
4299 '\x2e', '\x0f', '\x1f', // nopw %cs:0L(%rax,%rax,1)
4300 '\x84', '\x00', '\x00',
4301 '\x00', '\x00', '\x00' };
4302 const char nop13
[13] = { '\x66', '\x66', '\x66', // data16; data16; data16
4303 '\x66', '\x2e', '\x0f', // nopw %cs:0L(%rax,%rax,1)
4304 '\x1f', '\x84', '\x00',
4305 '\x00', '\x00', '\x00',
4307 const char nop14
[14] = { '\x66', '\x66', '\x66', // data16; data16; data16
4308 '\x66', '\x66', '\x2e', // data16
4309 '\x0f', '\x1f', '\x84', // nopw %cs:0L(%rax,%rax,1)
4310 '\x00', '\x00', '\x00',
4312 const char nop15
[15] = { '\x66', '\x66', '\x66', // data16; data16; data16
4313 '\x66', '\x66', '\x66', // data16; data16
4314 '\x2e', '\x0f', '\x1f', // nopw %cs:0L(%rax,%rax,1)
4315 '\x84', '\x00', '\x00',
4316 '\x00', '\x00', '\x00' };
4318 const char* nops
[16] = {
4320 nop1
, nop2
, nop3
, nop4
, nop5
, nop6
, nop7
,
4321 nop8
, nop9
, nop10
, nop11
, nop12
, nop13
, nop14
, nop15
4324 return std::string(nops
[length
], length
);
4327 // Return the addend to use for a target specific relocation. The
4328 // only target specific relocation is R_X86_64_TLSDESC for a local
4329 // symbol. We want to set the addend is the offset of the local
4330 // symbol in the TLS segment.
4334 Target_x86_64
<size
>::do_reloc_addend(void* arg
, unsigned int r_type
,
4337 gold_assert(r_type
== elfcpp::R_X86_64_TLSDESC
);
4338 uintptr_t intarg
= reinterpret_cast<uintptr_t>(arg
);
4339 gold_assert(intarg
< this->tlsdesc_reloc_info_
.size());
4340 const Tlsdesc_info
& ti(this->tlsdesc_reloc_info_
[intarg
]);
4341 const Symbol_value
<size
>* psymval
= ti
.object
->local_symbol(ti
.r_sym
);
4342 gold_assert(psymval
->is_tls_symbol());
4343 // The value of a TLS symbol is the offset in the TLS segment.
4344 return psymval
->value(ti
.object
, 0);
4347 // Return the value to use for the base of a DW_EH_PE_datarel offset
4348 // in an FDE. Solaris and SVR4 use DW_EH_PE_datarel because their
4349 // assembler can not write out the difference between two labels in
4350 // different sections, so instead of using a pc-relative value they
4351 // use an offset from the GOT.
4355 Target_x86_64
<size
>::do_ehframe_datarel_base() const
4357 gold_assert(this->global_offset_table_
!= NULL
);
4358 Symbol
* sym
= this->global_offset_table_
;
4359 Sized_symbol
<size
>* ssym
= static_cast<Sized_symbol
<size
>*>(sym
);
4360 return ssym
->value();
4363 // FNOFFSET in section SHNDX in OBJECT is the start of a function
4364 // compiled with -fsplit-stack. The function calls non-split-stack
4365 // code. We have to change the function so that it always ensures
4366 // that it has enough stack space to run some random function.
4370 Target_x86_64
<size
>::do_calls_non_split(Relobj
* object
, unsigned int shndx
,
4371 section_offset_type fnoffset
,
4372 section_size_type fnsize
,
4373 unsigned char* view
,
4374 section_size_type view_size
,
4376 std::string
* to
) const
4378 // The function starts with a comparison of the stack pointer and a
4379 // field in the TCB. This is followed by a jump.
4382 if (this->match_view(view
, view_size
, fnoffset
, "\x64\x48\x3b\x24\x25", 5)
4385 // We will call __morestack if the carry flag is set after this
4386 // comparison. We turn the comparison into an stc instruction
4388 view
[fnoffset
] = '\xf9';
4389 this->set_view_to_nop(view
, view_size
, fnoffset
+ 1, 8);
4391 // lea NN(%rsp),%r10
4392 // lea NN(%rsp),%r11
4393 else if ((this->match_view(view
, view_size
, fnoffset
,
4394 "\x4c\x8d\x94\x24", 4)
4395 || this->match_view(view
, view_size
, fnoffset
,
4396 "\x4c\x8d\x9c\x24", 4))
4399 // This is loading an offset from the stack pointer for a
4400 // comparison. The offset is negative, so we decrease the
4401 // offset by the amount of space we need for the stack. This
4402 // means we will avoid calling __morestack if there happens to
4403 // be plenty of space on the stack already.
4404 unsigned char* pval
= view
+ fnoffset
+ 4;
4405 uint32_t val
= elfcpp::Swap_unaligned
<32, false>::readval(pval
);
4406 val
-= parameters
->options().split_stack_adjust_size();
4407 elfcpp::Swap_unaligned
<32, false>::writeval(pval
, val
);
4411 if (!object
->has_no_split_stack())
4412 object
->error(_("failed to match split-stack sequence at "
4413 "section %u offset %0zx"),
4414 shndx
, static_cast<size_t>(fnoffset
));
4418 // We have to change the function so that it calls
4419 // __morestack_non_split instead of __morestack. The former will
4420 // allocate additional stack space.
4421 *from
= "__morestack";
4422 *to
= "__morestack_non_split";
4425 // The selector for x86_64 object files. Note this is never instantiated
4426 // directly. It's only used in Target_selector_x86_64_nacl, below.
4429 class Target_selector_x86_64
: public Target_selector_freebsd
4432 Target_selector_x86_64()
4433 : Target_selector_freebsd(elfcpp::EM_X86_64
, size
, false,
4435 ? "elf64-x86-64" : "elf32-x86-64"),
4437 ? "elf64-x86-64-freebsd"
4438 : "elf32-x86-64-freebsd"),
4439 (size
== 64 ? "elf_x86_64" : "elf32_x86_64"))
4443 do_instantiate_target()
4444 { return new Target_x86_64
<size
>(); }
4448 // NaCl variant. It uses different PLT contents.
4451 class Output_data_plt_x86_64_nacl
: public Output_data_plt_x86_64
<size
>
4454 Output_data_plt_x86_64_nacl(Layout
* layout
,
4455 Output_data_got
<64, false>* got
,
4456 Output_data_space
* got_plt
,
4457 Output_data_space
* got_irelative
)
4458 : Output_data_plt_x86_64
<size
>(layout
, plt_entry_size
,
4459 got
, got_plt
, got_irelative
)
4462 Output_data_plt_x86_64_nacl(Layout
* layout
,
4463 Output_data_got
<64, false>* got
,
4464 Output_data_space
* got_plt
,
4465 Output_data_space
* got_irelative
,
4466 unsigned int plt_count
)
4467 : Output_data_plt_x86_64
<size
>(layout
, plt_entry_size
,
4468 got
, got_plt
, got_irelative
,
4473 virtual unsigned int
4474 do_get_plt_entry_size() const
4475 { return plt_entry_size
; }
4478 do_add_eh_frame(Layout
* layout
)
4480 layout
->add_eh_frame_for_plt(this,
4481 this->plt_eh_frame_cie
,
4482 this->plt_eh_frame_cie_size
,
4484 plt_eh_frame_fde_size
);
4488 do_fill_first_plt_entry(unsigned char* pov
,
4489 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_addr
,
4490 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_addr
);
4492 virtual unsigned int
4493 do_fill_plt_entry(unsigned char* pov
,
4494 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
4495 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
4496 unsigned int got_offset
,
4497 unsigned int plt_offset
,
4498 unsigned int plt_index
);
4501 do_fill_tlsdesc_entry(unsigned char* pov
,
4502 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
4503 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
4504 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_base
,
4505 unsigned int tlsdesc_got_offset
,
4506 unsigned int plt_offset
);
4509 // The size of an entry in the PLT.
4510 static const int plt_entry_size
= 64;
4512 // The first entry in the PLT.
4513 static const unsigned char first_plt_entry
[plt_entry_size
];
4515 // Other entries in the PLT for an executable.
4516 static const unsigned char plt_entry
[plt_entry_size
];
4518 // The reserved TLSDESC entry in the PLT for an executable.
4519 static const unsigned char tlsdesc_plt_entry
[plt_entry_size
];
4521 // The .eh_frame unwind information for the PLT.
4522 static const int plt_eh_frame_fde_size
= 32;
4523 static const unsigned char plt_eh_frame_fde
[plt_eh_frame_fde_size
];
4527 class Target_x86_64_nacl
: public Target_x86_64
<size
>
4530 Target_x86_64_nacl()
4531 : Target_x86_64
<size
>(&x86_64_nacl_info
)
4534 virtual Output_data_plt_x86_64
<size
>*
4535 do_make_data_plt(Layout
* layout
,
4536 Output_data_got
<64, false>* got
,
4537 Output_data_space
* got_plt
,
4538 Output_data_space
* got_irelative
)
4540 return new Output_data_plt_x86_64_nacl
<size
>(layout
, got
, got_plt
,
4544 virtual Output_data_plt_x86_64
<size
>*
4545 do_make_data_plt(Layout
* layout
,
4546 Output_data_got
<64, false>* got
,
4547 Output_data_space
* got_plt
,
4548 Output_data_space
* got_irelative
,
4549 unsigned int plt_count
)
4551 return new Output_data_plt_x86_64_nacl
<size
>(layout
, got
, got_plt
,
4557 static const Target::Target_info x86_64_nacl_info
;
4561 const Target::Target_info Target_x86_64_nacl
<64>::x86_64_nacl_info
=
4564 false, // is_big_endian
4565 elfcpp::EM_X86_64
, // machine_code
4566 false, // has_make_symbol
4567 false, // has_resolve
4568 true, // has_code_fill
4569 true, // is_default_stack_executable
4570 true, // can_icf_inline_merge_sections
4572 "/lib64/ld-nacl-x86-64.so.1", // dynamic_linker
4573 0x20000, // default_text_segment_address
4574 0x10000, // abi_pagesize (overridable by -z max-page-size)
4575 0x10000, // common_pagesize (overridable by -z common-page-size)
4576 true, // isolate_execinstr
4577 0x10000000, // rosegment_gap
4578 elfcpp::SHN_UNDEF
, // small_common_shndx
4579 elfcpp::SHN_X86_64_LCOMMON
, // large_common_shndx
4580 0, // small_common_section_flags
4581 elfcpp::SHF_X86_64_LARGE
, // large_common_section_flags
4582 NULL
, // attributes_section
4583 NULL
// attributes_vendor
4587 const Target::Target_info Target_x86_64_nacl
<32>::x86_64_nacl_info
=
4590 false, // is_big_endian
4591 elfcpp::EM_X86_64
, // machine_code
4592 false, // has_make_symbol
4593 false, // has_resolve
4594 true, // has_code_fill
4595 true, // is_default_stack_executable
4596 true, // can_icf_inline_merge_sections
4598 "/lib/ld-nacl-x86-64.so.1", // dynamic_linker
4599 0x20000, // default_text_segment_address
4600 0x10000, // abi_pagesize (overridable by -z max-page-size)
4601 0x10000, // common_pagesize (overridable by -z common-page-size)
4602 true, // isolate_execinstr
4603 0x10000000, // rosegment_gap
4604 elfcpp::SHN_UNDEF
, // small_common_shndx
4605 elfcpp::SHN_X86_64_LCOMMON
, // large_common_shndx
4606 0, // small_common_section_flags
4607 elfcpp::SHF_X86_64_LARGE
, // large_common_section_flags
4608 NULL
, // attributes_section
4609 NULL
// attributes_vendor
4612 #define NACLMASK 0xe0 // 32-byte alignment mask.
4614 // The first entry in the PLT.
4618 Output_data_plt_x86_64_nacl
<size
>::first_plt_entry
[plt_entry_size
] =
4620 0xff, 0x35, // pushq contents of memory address
4621 0, 0, 0, 0, // replaced with address of .got + 8
4622 0x4c, 0x8b, 0x1d, // mov GOT+16(%rip), %r11
4623 0, 0, 0, 0, // replaced with address of .got + 16
4624 0x41, 0x83, 0xe3, NACLMASK
, // and $-32, %r11d
4625 0x4d, 0x01, 0xfb, // add %r15, %r11
4626 0x41, 0xff, 0xe3, // jmpq *%r11
4628 // 9-byte nop sequence to pad out to the next 32-byte boundary.
4629 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopl %cs:0x0(%rax,%rax,1)
4631 // 32 bytes of nop to pad out to the standard size
4632 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, // excess data32 prefixes
4633 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4634 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, // excess data32 prefixes
4635 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4636 0x66, // excess data32 prefix
4642 Output_data_plt_x86_64_nacl
<size
>::do_fill_first_plt_entry(
4644 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
4645 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
)
4647 memcpy(pov
, first_plt_entry
, plt_entry_size
);
4648 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
4650 - (plt_address
+ 2 + 4)));
4651 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 9,
4653 - (plt_address
+ 9 + 4)));
4656 // Subsequent entries in the PLT.
4660 Output_data_plt_x86_64_nacl
<size
>::plt_entry
[plt_entry_size
] =
4662 0x4c, 0x8b, 0x1d, // mov name@GOTPCREL(%rip),%r11
4663 0, 0, 0, 0, // replaced with address of symbol in .got
4664 0x41, 0x83, 0xe3, NACLMASK
, // and $-32, %r11d
4665 0x4d, 0x01, 0xfb, // add %r15, %r11
4666 0x41, 0xff, 0xe3, // jmpq *%r11
4668 // 15-byte nop sequence to pad out to the next 32-byte boundary.
4669 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, // excess data32 prefixes
4670 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4672 // Lazy GOT entries point here (32-byte aligned).
4673 0x68, // pushq immediate
4674 0, 0, 0, 0, // replaced with index into relocation table
4675 0xe9, // jmp relative
4676 0, 0, 0, 0, // replaced with offset to start of .plt0
4678 // 22 bytes of nop to pad out to the standard size.
4679 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, // excess data32 prefixes
4680 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4681 0x0f, 0x1f, 0x80, 0, 0, 0, 0, // nopl 0x0(%rax)
4686 Output_data_plt_x86_64_nacl
<size
>::do_fill_plt_entry(
4688 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
4689 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
4690 unsigned int got_offset
,
4691 unsigned int plt_offset
,
4692 unsigned int plt_index
)
4694 memcpy(pov
, plt_entry
, plt_entry_size
);
4695 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 3,
4696 (got_address
+ got_offset
4697 - (plt_address
+ plt_offset
4700 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 33, plt_index
);
4701 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 38,
4702 - (plt_offset
+ 38 + 4));
4707 // The reserved TLSDESC entry in the PLT.
4711 Output_data_plt_x86_64_nacl
<size
>::tlsdesc_plt_entry
[plt_entry_size
] =
4713 0xff, 0x35, // pushq x(%rip)
4714 0, 0, 0, 0, // replaced with address of linkmap GOT entry (at PLTGOT + 8)
4715 0x4c, 0x8b, 0x1d, // mov y(%rip),%r11
4716 0, 0, 0, 0, // replaced with offset of reserved TLSDESC_GOT entry
4717 0x41, 0x83, 0xe3, NACLMASK
, // and $-32, %r11d
4718 0x4d, 0x01, 0xfb, // add %r15, %r11
4719 0x41, 0xff, 0xe3, // jmpq *%r11
4721 // 41 bytes of nop to pad out to the standard size.
4722 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, // excess data32 prefixes
4723 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4724 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, // excess data32 prefixes
4725 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4726 0x66, 0x66, // excess data32 prefixes
4727 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
4732 Output_data_plt_x86_64_nacl
<size
>::do_fill_tlsdesc_entry(
4734 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
4735 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
4736 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_base
,
4737 unsigned int tlsdesc_got_offset
,
4738 unsigned int plt_offset
)
4740 memcpy(pov
, tlsdesc_plt_entry
, plt_entry_size
);
4741 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
4743 - (plt_address
+ plt_offset
4745 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 9,
4747 + tlsdesc_got_offset
4748 - (plt_address
+ plt_offset
4752 // The .eh_frame unwind information for the PLT.
4756 Output_data_plt_x86_64_nacl
<size
>::plt_eh_frame_fde
[plt_eh_frame_fde_size
] =
4758 0, 0, 0, 0, // Replaced with offset to .plt.
4759 0, 0, 0, 0, // Replaced with size of .plt.
4760 0, // Augmentation size.
4761 elfcpp::DW_CFA_def_cfa_offset
, 16, // DW_CFA_def_cfa_offset: 16.
4762 elfcpp::DW_CFA_advance_loc
+ 6, // Advance 6 to __PLT__ + 6.
4763 elfcpp::DW_CFA_def_cfa_offset
, 24, // DW_CFA_def_cfa_offset: 24.
4764 elfcpp::DW_CFA_advance_loc
+ 58, // Advance 58 to __PLT__ + 64.
4765 elfcpp::DW_CFA_def_cfa_expression
, // DW_CFA_def_cfa_expression.
4766 13, // Block length.
4767 elfcpp::DW_OP_breg7
, 8, // Push %rsp + 8.
4768 elfcpp::DW_OP_breg16
, 0, // Push %rip.
4769 elfcpp::DW_OP_const1u
, 63, // Push 0x3f.
4770 elfcpp::DW_OP_and
, // & (%rip & 0x3f).
4771 elfcpp::DW_OP_const1u
, 37, // Push 0x25.
4772 elfcpp::DW_OP_ge
, // >= ((%rip & 0x3f) >= 0x25)
4773 elfcpp::DW_OP_lit3
, // Push 3.
4774 elfcpp::DW_OP_shl
, // << (((%rip & 0x3f) >= 0x25) << 3)
4775 elfcpp::DW_OP_plus
, // + ((((%rip&0x3f)>=0x25)<<3)+%rsp+8
4776 elfcpp::DW_CFA_nop
, // Align to 32 bytes.
4780 // The selector for x86_64-nacl object files.
4783 class Target_selector_x86_64_nacl
4784 : public Target_selector_nacl
<Target_selector_x86_64
<size
>,
4785 Target_x86_64_nacl
<size
> >
4788 Target_selector_x86_64_nacl()
4789 : Target_selector_nacl
<Target_selector_x86_64
<size
>,
4790 Target_x86_64_nacl
<size
> >("x86-64",
4792 ? "elf64-x86-64-nacl"
4793 : "elf32-x86-64-nacl",
4796 : "elf32_x86_64_nacl")
4800 Target_selector_x86_64_nacl
<64> target_selector_x86_64
;
4801 Target_selector_x86_64_nacl
<32> target_selector_x32
;
4803 } // End anonymous namespace.