1 // x86_64.cc -- x86_64 target support for gold.
3 // Copyright 2006, 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
4 // Written by Ian Lance Taylor <iant@google.com>.
6 // This file is part of gold.
8 // This program is free software; you can redistribute it and/or modify
9 // it under the terms of the GNU General Public License as published by
10 // the Free Software Foundation; either version 3 of the License, or
11 // (at your option) any later version.
13 // This program is distributed in the hope that it will be useful,
14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 // GNU General Public License for more details.
18 // You should have received a copy of the GNU General Public License
19 // along with this program; if not, write to the Free Software
20 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
21 // MA 02110-1301, USA.
29 #include "parameters.h"
36 #include "copy-relocs.h"
38 #include "target-reloc.h"
39 #include "target-select.h"
50 // A class to handle the PLT data.
53 class Output_data_plt_x86_64
: public Output_section_data
56 typedef Output_data_reloc
<elfcpp::SHT_RELA
, true, size
, false> Reloc_section
;
58 Output_data_plt_x86_64(Layout
* layout
, Output_data_got
<64, false>* got
,
59 Output_data_space
* got_plt
,
60 Output_data_space
* got_irelative
)
61 : Output_section_data(16), layout_(layout
), tlsdesc_rel_(NULL
),
62 irelative_rel_(NULL
), got_(got
), got_plt_(got_plt
),
63 got_irelative_(got_irelative
), count_(0), irelative_count_(0),
64 tlsdesc_got_offset_(-1U), free_list_()
65 { this->init(layout
); }
67 Output_data_plt_x86_64(Layout
* layout
, Output_data_got
<64, false>* got
,
68 Output_data_space
* got_plt
,
69 Output_data_space
* got_irelative
,
70 unsigned int plt_count
)
71 : Output_section_data((plt_count
+ 1) * plt_entry_size
, 16, false),
72 layout_(layout
), tlsdesc_rel_(NULL
), irelative_rel_(NULL
), got_(got
),
73 got_plt_(got_plt
), got_irelative_(got_irelative
), count_(plt_count
),
74 irelative_count_(0), tlsdesc_got_offset_(-1U), free_list_()
78 // Initialize the free list and reserve the first entry.
79 this->free_list_
.init((plt_count
+ 1) * plt_entry_size
, false);
80 this->free_list_
.remove(0, plt_entry_size
);
83 // Initialize the PLT section.
87 // Add an entry to the PLT.
89 add_entry(Symbol_table
*, Layout
*, Symbol
* gsym
);
91 // Add an entry to the PLT for a local STT_GNU_IFUNC symbol.
93 add_local_ifunc_entry(Symbol_table
* symtab
, Layout
*,
94 Sized_relobj_file
<size
, false>* relobj
,
95 unsigned int local_sym_index
);
97 // Add the relocation for a PLT entry.
99 add_relocation(Symbol_table
*, Layout
*, Symbol
* gsym
,
100 unsigned int got_offset
);
102 // Add the reserved TLSDESC_PLT entry to the PLT.
104 reserve_tlsdesc_entry(unsigned int got_offset
)
105 { this->tlsdesc_got_offset_
= got_offset
; }
107 // Return true if a TLSDESC_PLT entry has been reserved.
109 has_tlsdesc_entry() const
110 { return this->tlsdesc_got_offset_
!= -1U; }
112 // Return the GOT offset for the reserved TLSDESC_PLT entry.
114 get_tlsdesc_got_offset() const
115 { return this->tlsdesc_got_offset_
; }
117 // Return the offset of the reserved TLSDESC_PLT entry.
119 get_tlsdesc_plt_offset() const
120 { return (this->count_
+ this->irelative_count_
+ 1) * plt_entry_size
; }
122 // Return the .rela.plt section data.
125 { return this->rel_
; }
127 // Return where the TLSDESC relocations should go.
129 rela_tlsdesc(Layout
*);
131 // Return where the IRELATIVE relocations should go in the PLT
134 rela_irelative(Symbol_table
*, Layout
*);
136 // Return whether we created a section for IRELATIVE relocations.
138 has_irelative_section() const
139 { return this->irelative_rel_
!= NULL
; }
141 // Return the number of PLT entries.
144 { return this->count_
+ this->irelative_count_
; }
146 // Return the offset of the first non-reserved PLT entry.
148 first_plt_entry_offset()
149 { return plt_entry_size
; }
151 // Return the size of a PLT entry.
154 { return plt_entry_size
; }
156 // Reserve a slot in the PLT for an existing symbol in an incremental update.
158 reserve_slot(unsigned int plt_index
)
160 this->free_list_
.remove((plt_index
+ 1) * plt_entry_size
,
161 (plt_index
+ 2) * plt_entry_size
);
164 // Return the PLT address to use for a global symbol.
166 address_for_global(const Symbol
*);
168 // Return the PLT address to use for a local symbol.
170 address_for_local(const Relobj
*, unsigned int symndx
);
174 do_adjust_output_section(Output_section
* os
);
176 // Write to a map file.
178 do_print_to_mapfile(Mapfile
* mapfile
) const
179 { mapfile
->print_output_data(this, _("** PLT")); }
182 // The size of an entry in the PLT.
183 static const int plt_entry_size
= 16;
185 // The first entry in the PLT.
186 // From the AMD64 ABI: "Unlike Intel386 ABI, this ABI uses the same
187 // procedure linkage table for both programs and shared objects."
188 static const unsigned char first_plt_entry
[plt_entry_size
];
190 // Other entries in the PLT for an executable.
191 static const unsigned char plt_entry
[plt_entry_size
];
193 // The reserved TLSDESC entry in the PLT for an executable.
194 static const unsigned char tlsdesc_plt_entry
[plt_entry_size
];
196 // The .eh_frame unwind information for the PLT.
197 static const int plt_eh_frame_cie_size
= 16;
198 static const int plt_eh_frame_fde_size
= 32;
199 static const unsigned char plt_eh_frame_cie
[plt_eh_frame_cie_size
];
200 static const unsigned char plt_eh_frame_fde
[plt_eh_frame_fde_size
];
202 // Set the final size.
204 set_final_data_size();
206 // Write out the PLT data.
208 do_write(Output_file
*);
210 // A pointer to the Layout class, so that we can find the .dynamic
211 // section when we write out the GOT PLT section.
213 // The reloc section.
215 // The TLSDESC relocs, if necessary. These must follow the regular
217 Reloc_section
* tlsdesc_rel_
;
218 // The IRELATIVE relocs, if necessary. These must follow the
219 // regular PLT relocations and the TLSDESC relocations.
220 Reloc_section
* irelative_rel_
;
222 Output_data_got
<64, false>* got_
;
223 // The .got.plt section.
224 Output_data_space
* got_plt_
;
225 // The part of the .got.plt section used for IRELATIVE relocs.
226 Output_data_space
* got_irelative_
;
227 // The number of PLT entries.
229 // Number of PLT entries with R_X86_64_IRELATIVE relocs. These
230 // follow the regular PLT entries.
231 unsigned int irelative_count_
;
232 // Offset of the reserved TLSDESC_GOT entry when needed.
233 unsigned int tlsdesc_got_offset_
;
234 // List of available regions within the section, for incremental
236 Free_list free_list_
;
239 // The x86_64 target class.
241 // http://www.x86-64.org/documentation/abi.pdf
242 // TLS info comes from
243 // http://people.redhat.com/drepper/tls.pdf
244 // http://www.lsd.ic.unicamp.br/~oliva/writeups/TLS/RFC-TLSDESC-x86.txt
247 class Target_x86_64
: public Sized_target
<size
, false>
250 // In the x86_64 ABI (p 68), it says "The AMD64 ABI architectures
251 // uses only Elf64_Rela relocation entries with explicit addends."
252 typedef Output_data_reloc
<elfcpp::SHT_RELA
, true, size
, false> Reloc_section
;
255 : Sized_target
<size
, false>(&x86_64_info
),
256 got_(NULL
), plt_(NULL
), got_plt_(NULL
), got_irelative_(NULL
),
257 got_tlsdesc_(NULL
), global_offset_table_(NULL
), rela_dyn_(NULL
),
258 rela_irelative_(NULL
), copy_relocs_(elfcpp::R_X86_64_COPY
),
259 dynbss_(NULL
), got_mod_index_offset_(-1U), tlsdesc_reloc_info_(),
260 tls_base_symbol_defined_(false)
263 // Hook for a new output section.
265 do_new_output_section(Output_section
*) const;
267 // Scan the relocations to look for symbol adjustments.
269 gc_process_relocs(Symbol_table
* symtab
,
271 Sized_relobj_file
<size
, false>* object
,
272 unsigned int data_shndx
,
273 unsigned int sh_type
,
274 const unsigned char* prelocs
,
276 Output_section
* output_section
,
277 bool needs_special_offset_handling
,
278 size_t local_symbol_count
,
279 const unsigned char* plocal_symbols
);
281 // Scan the relocations to look for symbol adjustments.
283 scan_relocs(Symbol_table
* symtab
,
285 Sized_relobj_file
<size
, false>* object
,
286 unsigned int data_shndx
,
287 unsigned int sh_type
,
288 const unsigned char* prelocs
,
290 Output_section
* output_section
,
291 bool needs_special_offset_handling
,
292 size_t local_symbol_count
,
293 const unsigned char* plocal_symbols
);
295 // Finalize the sections.
297 do_finalize_sections(Layout
*, const Input_objects
*, Symbol_table
*);
299 // Return the value to use for a dynamic which requires special
302 do_dynsym_value(const Symbol
*) const;
304 // Relocate a section.
306 relocate_section(const Relocate_info
<size
, false>*,
307 unsigned int sh_type
,
308 const unsigned char* prelocs
,
310 Output_section
* output_section
,
311 bool needs_special_offset_handling
,
313 typename
elfcpp::Elf_types
<size
>::Elf_Addr view_address
,
314 section_size_type view_size
,
315 const Reloc_symbol_changes
*);
317 // Scan the relocs during a relocatable link.
319 scan_relocatable_relocs(Symbol_table
* symtab
,
321 Sized_relobj_file
<size
, false>* object
,
322 unsigned int data_shndx
,
323 unsigned int sh_type
,
324 const unsigned char* prelocs
,
326 Output_section
* output_section
,
327 bool needs_special_offset_handling
,
328 size_t local_symbol_count
,
329 const unsigned char* plocal_symbols
,
330 Relocatable_relocs
*);
332 // Relocate a section during a relocatable link.
334 relocate_for_relocatable(
335 const Relocate_info
<size
, false>*,
336 unsigned int sh_type
,
337 const unsigned char* prelocs
,
339 Output_section
* output_section
,
340 off_t offset_in_output_section
,
341 const Relocatable_relocs
*,
343 typename
elfcpp::Elf_types
<size
>::Elf_Addr view_address
,
344 section_size_type view_size
,
345 unsigned char* reloc_view
,
346 section_size_type reloc_view_size
);
348 // Return a string used to fill a code section with nops.
350 do_code_fill(section_size_type length
) const;
352 // Return whether SYM is defined by the ABI.
354 do_is_defined_by_abi(const Symbol
* sym
) const
355 { return strcmp(sym
->name(), "__tls_get_addr") == 0; }
357 // Return the symbol index to use for a target specific relocation.
358 // The only target specific relocation is R_X86_64_TLSDESC for a
359 // local symbol, which is an absolute reloc.
361 do_reloc_symbol_index(void*, unsigned int r_type
) const
363 gold_assert(r_type
== elfcpp::R_X86_64_TLSDESC
);
367 // Return the addend to use for a target specific relocation.
369 do_reloc_addend(void* arg
, unsigned int r_type
, uint64_t addend
) const;
371 // Return the PLT section.
373 do_plt_address_for_global(const Symbol
* gsym
) const
374 { return this->plt_section()->address_for_global(gsym
); }
377 do_plt_address_for_local(const Relobj
* relobj
, unsigned int symndx
) const
378 { return this->plt_section()->address_for_local(relobj
, symndx
); }
380 // This function should be defined in targets that can use relocation
381 // types to determine (implemented in local_reloc_may_be_function_pointer
382 // and global_reloc_may_be_function_pointer)
383 // if a function's pointer is taken. ICF uses this in safe mode to only
384 // fold those functions whose pointer is defintely not taken. For x86_64
385 // pie binaries, safe ICF cannot be done by looking at relocation types.
387 do_can_check_for_function_pointers() const
388 { return !parameters
->options().pie(); }
390 // Return the base for a DW_EH_PE_datarel encoding.
392 do_ehframe_datarel_base() const;
394 // Adjust -fsplit-stack code which calls non-split-stack code.
396 do_calls_non_split(Relobj
* object
, unsigned int shndx
,
397 section_offset_type fnoffset
, section_size_type fnsize
,
398 unsigned char* view
, section_size_type view_size
,
399 std::string
* from
, std::string
* to
) const;
401 // Return the size of the GOT section.
405 gold_assert(this->got_
!= NULL
);
406 return this->got_
->data_size();
409 // Return the number of entries in the GOT.
411 got_entry_count() const
413 if (this->got_
== NULL
)
415 return this->got_size() / 8;
418 // Return the number of entries in the PLT.
420 plt_entry_count() const;
422 // Return the offset of the first non-reserved PLT entry.
424 first_plt_entry_offset() const;
426 // Return the size of each PLT entry.
428 plt_entry_size() const;
430 // Create the GOT section for an incremental update.
431 Output_data_got_base
*
432 init_got_plt_for_update(Symbol_table
* symtab
,
434 unsigned int got_count
,
435 unsigned int plt_count
);
437 // Reserve a GOT entry for a local symbol, and regenerate any
438 // necessary dynamic relocations.
440 reserve_local_got_entry(unsigned int got_index
,
441 Sized_relobj
<size
, false>* obj
,
443 unsigned int got_type
);
445 // Reserve a GOT entry for a global symbol, and regenerate any
446 // necessary dynamic relocations.
448 reserve_global_got_entry(unsigned int got_index
, Symbol
* gsym
,
449 unsigned int got_type
);
451 // Register an existing PLT entry for a global symbol.
453 register_global_plt_entry(Symbol_table
*, Layout
*, unsigned int plt_index
,
456 // Force a COPY relocation for a given symbol.
458 emit_copy_reloc(Symbol_table
*, Symbol
*, Output_section
*, off_t
);
460 // Apply an incremental relocation.
462 apply_relocation(const Relocate_info
<size
, false>* relinfo
,
463 typename
elfcpp::Elf_types
<size
>::Elf_Addr r_offset
,
465 typename
elfcpp::Elf_types
<size
>::Elf_Swxword r_addend
,
468 typename
elfcpp::Elf_types
<size
>::Elf_Addr address
,
469 section_size_type view_size
);
471 // Add a new reloc argument, returning the index in the vector.
473 add_tlsdesc_info(Sized_relobj_file
<size
, false>* object
, unsigned int r_sym
)
475 this->tlsdesc_reloc_info_
.push_back(Tlsdesc_info(object
, r_sym
));
476 return this->tlsdesc_reloc_info_
.size() - 1;
480 // The class which scans relocations.
485 : issued_non_pic_error_(false)
489 get_reference_flags(unsigned int r_type
);
492 local(Symbol_table
* symtab
, Layout
* layout
, Target_x86_64
* target
,
493 Sized_relobj_file
<size
, false>* object
,
494 unsigned int data_shndx
,
495 Output_section
* output_section
,
496 const elfcpp::Rela
<size
, false>& reloc
, unsigned int r_type
,
497 const elfcpp::Sym
<size
, false>& lsym
);
500 global(Symbol_table
* symtab
, Layout
* layout
, Target_x86_64
* target
,
501 Sized_relobj_file
<size
, false>* object
,
502 unsigned int data_shndx
,
503 Output_section
* output_section
,
504 const elfcpp::Rela
<size
, false>& reloc
, unsigned int r_type
,
508 local_reloc_may_be_function_pointer(Symbol_table
* symtab
, Layout
* layout
,
509 Target_x86_64
* target
,
510 Sized_relobj_file
<size
, false>* object
,
511 unsigned int data_shndx
,
512 Output_section
* output_section
,
513 const elfcpp::Rela
<size
, false>& reloc
,
515 const elfcpp::Sym
<size
, false>& lsym
);
518 global_reloc_may_be_function_pointer(Symbol_table
* symtab
, Layout
* layout
,
519 Target_x86_64
* target
,
520 Sized_relobj_file
<size
, false>* object
,
521 unsigned int data_shndx
,
522 Output_section
* output_section
,
523 const elfcpp::Rela
<size
, false>& reloc
,
529 unsupported_reloc_local(Sized_relobj_file
<size
, false>*,
530 unsigned int r_type
);
533 unsupported_reloc_global(Sized_relobj_file
<size
, false>*,
534 unsigned int r_type
, Symbol
*);
537 check_non_pic(Relobj
*, unsigned int r_type
, Symbol
*);
540 possible_function_pointer_reloc(unsigned int r_type
);
543 reloc_needs_plt_for_ifunc(Sized_relobj_file
<size
, false>*,
544 unsigned int r_type
);
546 // Whether we have issued an error about a non-PIC compilation.
547 bool issued_non_pic_error_
;
550 // The class which implements relocation.
555 : skip_call_tls_get_addr_(false)
560 if (this->skip_call_tls_get_addr_
)
562 // FIXME: This needs to specify the location somehow.
563 gold_error(_("missing expected TLS relocation"));
567 // Do a relocation. Return false if the caller should not issue
568 // any warnings about this relocation.
570 relocate(const Relocate_info
<size
, false>*, Target_x86_64
*,
572 size_t relnum
, const elfcpp::Rela
<size
, false>&,
573 unsigned int r_type
, const Sized_symbol
<size
>*,
574 const Symbol_value
<size
>*,
575 unsigned char*, typename
elfcpp::Elf_types
<size
>::Elf_Addr
,
579 // Do a TLS relocation.
581 relocate_tls(const Relocate_info
<size
, false>*, Target_x86_64
*,
582 size_t relnum
, const elfcpp::Rela
<size
, false>&,
583 unsigned int r_type
, const Sized_symbol
<size
>*,
584 const Symbol_value
<size
>*,
585 unsigned char*, typename
elfcpp::Elf_types
<size
>::Elf_Addr
,
588 // Do a TLS General-Dynamic to Initial-Exec transition.
590 tls_gd_to_ie(const Relocate_info
<size
, false>*, size_t relnum
,
591 Output_segment
* tls_segment
,
592 const elfcpp::Rela
<size
, false>&, unsigned int r_type
,
593 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
595 typename
elfcpp::Elf_types
<size
>::Elf_Addr
,
596 section_size_type view_size
);
598 // Do a TLS General-Dynamic to Local-Exec transition.
600 tls_gd_to_le(const Relocate_info
<size
, false>*, size_t relnum
,
601 Output_segment
* tls_segment
,
602 const elfcpp::Rela
<size
, false>&, unsigned int r_type
,
603 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
605 section_size_type view_size
);
607 // Do a TLSDESC-style General-Dynamic to Initial-Exec transition.
609 tls_desc_gd_to_ie(const Relocate_info
<size
, false>*, size_t relnum
,
610 Output_segment
* tls_segment
,
611 const elfcpp::Rela
<size
, false>&, unsigned int r_type
,
612 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
614 typename
elfcpp::Elf_types
<size
>::Elf_Addr
,
615 section_size_type view_size
);
617 // Do a TLSDESC-style General-Dynamic to Local-Exec transition.
619 tls_desc_gd_to_le(const Relocate_info
<size
, false>*, size_t relnum
,
620 Output_segment
* tls_segment
,
621 const elfcpp::Rela
<size
, false>&, unsigned int r_type
,
622 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
624 section_size_type view_size
);
626 // Do a TLS Local-Dynamic to Local-Exec transition.
628 tls_ld_to_le(const Relocate_info
<size
, false>*, size_t relnum
,
629 Output_segment
* tls_segment
,
630 const elfcpp::Rela
<size
, false>&, unsigned int r_type
,
631 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
633 section_size_type view_size
);
635 // Do a TLS Initial-Exec to Local-Exec transition.
637 tls_ie_to_le(const Relocate_info
<size
, false>*, size_t relnum
,
638 Output_segment
* tls_segment
,
639 const elfcpp::Rela
<size
, false>&, unsigned int r_type
,
640 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
642 section_size_type view_size
);
644 // This is set if we should skip the next reloc, which should be a
645 // PLT32 reloc against ___tls_get_addr.
646 bool skip_call_tls_get_addr_
;
649 // A class which returns the size required for a relocation type,
650 // used while scanning relocs during a relocatable link.
651 class Relocatable_size_for_reloc
655 get_size_for_reloc(unsigned int, Relobj
*);
658 // Adjust TLS relocation type based on the options and whether this
659 // is a local symbol.
660 static tls::Tls_optimization
661 optimize_tls_reloc(bool is_final
, int r_type
);
663 // Get the GOT section, creating it if necessary.
664 Output_data_got
<64, false>*
665 got_section(Symbol_table
*, Layout
*);
667 // Get the GOT PLT section.
669 got_plt_section() const
671 gold_assert(this->got_plt_
!= NULL
);
672 return this->got_plt_
;
675 // Get the GOT section for TLSDESC entries.
676 Output_data_got
<64, false>*
677 got_tlsdesc_section() const
679 gold_assert(this->got_tlsdesc_
!= NULL
);
680 return this->got_tlsdesc_
;
683 // Create the PLT section.
685 make_plt_section(Symbol_table
* symtab
, Layout
* layout
);
687 // Create a PLT entry for a global symbol.
689 make_plt_entry(Symbol_table
*, Layout
*, Symbol
*);
691 // Create a PLT entry for a local STT_GNU_IFUNC symbol.
693 make_local_ifunc_plt_entry(Symbol_table
*, Layout
*,
694 Sized_relobj_file
<size
, false>* relobj
,
695 unsigned int local_sym_index
);
697 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
699 define_tls_base_symbol(Symbol_table
*, Layout
*);
701 // Create the reserved PLT and GOT entries for the TLS descriptor resolver.
703 reserve_tlsdesc_entries(Symbol_table
* symtab
, Layout
* layout
);
705 // Create a GOT entry for the TLS module index.
707 got_mod_index_entry(Symbol_table
* symtab
, Layout
* layout
,
708 Sized_relobj_file
<size
, false>* object
);
710 // Get the PLT section.
711 Output_data_plt_x86_64
<size
>*
714 gold_assert(this->plt_
!= NULL
);
718 // Get the dynamic reloc section, creating it if necessary.
720 rela_dyn_section(Layout
*);
722 // Get the section to use for TLSDESC relocations.
724 rela_tlsdesc_section(Layout
*) const;
726 // Get the section to use for IRELATIVE relocations.
728 rela_irelative_section(Layout
*);
730 // Add a potential copy relocation.
732 copy_reloc(Symbol_table
* symtab
, Layout
* layout
,
733 Sized_relobj_file
<size
, false>* object
,
734 unsigned int shndx
, Output_section
* output_section
,
735 Symbol
* sym
, const elfcpp::Rela
<size
, false>& reloc
)
737 this->copy_relocs_
.copy_reloc(symtab
, layout
,
738 symtab
->get_sized_symbol
<size
>(sym
),
739 object
, shndx
, output_section
,
740 reloc
, this->rela_dyn_section(layout
));
743 // Information about this specific target which we pass to the
744 // general Target structure.
745 static const Target::Target_info x86_64_info
;
747 // The types of GOT entries needed for this platform.
748 // These values are exposed to the ABI in an incremental link.
749 // Do not renumber existing values without changing the version
750 // number of the .gnu_incremental_inputs section.
753 GOT_TYPE_STANDARD
= 0, // GOT entry for a regular symbol
754 GOT_TYPE_TLS_OFFSET
= 1, // GOT entry for TLS offset
755 GOT_TYPE_TLS_PAIR
= 2, // GOT entry for TLS module/offset pair
756 GOT_TYPE_TLS_DESC
= 3 // GOT entry for TLS_DESC pair
759 // This type is used as the argument to the target specific
760 // relocation routines. The only target specific reloc is
761 // R_X86_64_TLSDESC against a local symbol.
764 Tlsdesc_info(Sized_relobj_file
<size
, false>* a_object
, unsigned int a_r_sym
)
765 : object(a_object
), r_sym(a_r_sym
)
768 // The object in which the local symbol is defined.
769 Sized_relobj_file
<size
, false>* object
;
770 // The local symbol index in the object.
775 Output_data_got
<64, false>* got_
;
777 Output_data_plt_x86_64
<size
>* plt_
;
778 // The GOT PLT section.
779 Output_data_space
* got_plt_
;
780 // The GOT section for IRELATIVE relocations.
781 Output_data_space
* got_irelative_
;
782 // The GOT section for TLSDESC relocations.
783 Output_data_got
<64, false>* got_tlsdesc_
;
784 // The _GLOBAL_OFFSET_TABLE_ symbol.
785 Symbol
* global_offset_table_
;
786 // The dynamic reloc section.
787 Reloc_section
* rela_dyn_
;
788 // The section to use for IRELATIVE relocs.
789 Reloc_section
* rela_irelative_
;
790 // Relocs saved to avoid a COPY reloc.
791 Copy_relocs
<elfcpp::SHT_RELA
, size
, false> copy_relocs_
;
792 // Space for variables copied with a COPY reloc.
793 Output_data_space
* dynbss_
;
794 // Offset of the GOT entry for the TLS module index.
795 unsigned int got_mod_index_offset_
;
796 // We handle R_X86_64_TLSDESC against a local symbol as a target
797 // specific relocation. Here we store the object and local symbol
798 // index for the relocation.
799 std::vector
<Tlsdesc_info
> tlsdesc_reloc_info_
;
800 // True if the _TLS_MODULE_BASE_ symbol has been defined.
801 bool tls_base_symbol_defined_
;
805 const Target::Target_info Target_x86_64
<64>::x86_64_info
=
808 false, // is_big_endian
809 elfcpp::EM_X86_64
, // machine_code
810 false, // has_make_symbol
811 false, // has_resolve
812 true, // has_code_fill
813 true, // is_default_stack_executable
814 true, // can_icf_inline_merge_sections
816 "/lib/ld64.so.1", // program interpreter
817 0x400000, // default_text_segment_address
818 0x1000, // abi_pagesize (overridable by -z max-page-size)
819 0x1000, // common_pagesize (overridable by -z common-page-size)
820 elfcpp::SHN_UNDEF
, // small_common_shndx
821 elfcpp::SHN_X86_64_LCOMMON
, // large_common_shndx
822 0, // small_common_section_flags
823 elfcpp::SHF_X86_64_LARGE
, // large_common_section_flags
824 NULL
, // attributes_section
825 NULL
// attributes_vendor
829 const Target::Target_info Target_x86_64
<32>::x86_64_info
=
832 false, // is_big_endian
833 elfcpp::EM_X86_64
, // machine_code
834 false, // has_make_symbol
835 false, // has_resolve
836 true, // has_code_fill
837 true, // is_default_stack_executable
838 true, // can_icf_inline_merge_sections
840 "/libx32/ldx32.so.1", // program interpreter
841 0x400000, // default_text_segment_address
842 0x1000, // abi_pagesize (overridable by -z max-page-size)
843 0x1000, // common_pagesize (overridable by -z common-page-size)
844 elfcpp::SHN_UNDEF
, // small_common_shndx
845 elfcpp::SHN_X86_64_LCOMMON
, // large_common_shndx
846 0, // small_common_section_flags
847 elfcpp::SHF_X86_64_LARGE
, // large_common_section_flags
848 NULL
, // attributes_section
849 NULL
// attributes_vendor
852 // This is called when a new output section is created. This is where
853 // we handle the SHF_X86_64_LARGE.
857 Target_x86_64
<size
>::do_new_output_section(Output_section
* os
) const
859 if ((os
->flags() & elfcpp::SHF_X86_64_LARGE
) != 0)
860 os
->set_is_large_section();
863 // Get the GOT section, creating it if necessary.
866 Output_data_got
<64, false>*
867 Target_x86_64
<size
>::got_section(Symbol_table
* symtab
, Layout
* layout
)
869 if (this->got_
== NULL
)
871 gold_assert(symtab
!= NULL
&& layout
!= NULL
);
873 // When using -z now, we can treat .got.plt as a relro section.
874 // Without -z now, it is modified after program startup by lazy
876 bool is_got_plt_relro
= parameters
->options().now();
877 Output_section_order got_order
= (is_got_plt_relro
880 Output_section_order got_plt_order
= (is_got_plt_relro
882 : ORDER_NON_RELRO_FIRST
);
884 this->got_
= new Output_data_got
<64, false>();
886 layout
->add_output_section_data(".got", elfcpp::SHT_PROGBITS
,
888 | elfcpp::SHF_WRITE
),
889 this->got_
, got_order
, true);
891 this->got_plt_
= new Output_data_space(8, "** GOT PLT");
892 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
894 | elfcpp::SHF_WRITE
),
895 this->got_plt_
, got_plt_order
,
898 // The first three entries are reserved.
899 this->got_plt_
->set_current_data_size(3 * 8);
901 if (!is_got_plt_relro
)
903 // Those bytes can go into the relro segment.
904 layout
->increase_relro(3 * 8);
907 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
908 this->global_offset_table_
=
909 symtab
->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL
,
910 Symbol_table::PREDEFINED
,
912 0, 0, elfcpp::STT_OBJECT
,
914 elfcpp::STV_HIDDEN
, 0,
917 // If there are any IRELATIVE relocations, they get GOT entries
918 // in .got.plt after the jump slot entries.
919 this->got_irelative_
= new Output_data_space(8, "** GOT IRELATIVE PLT");
920 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
922 | elfcpp::SHF_WRITE
),
923 this->got_irelative_
,
924 got_plt_order
, is_got_plt_relro
);
926 // If there are any TLSDESC relocations, they get GOT entries in
927 // .got.plt after the jump slot and IRELATIVE entries.
928 this->got_tlsdesc_
= new Output_data_got
<64, false>();
929 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
931 | elfcpp::SHF_WRITE
),
933 got_plt_order
, is_got_plt_relro
);
939 // Get the dynamic reloc section, creating it if necessary.
942 typename Target_x86_64
<size
>::Reloc_section
*
943 Target_x86_64
<size
>::rela_dyn_section(Layout
* layout
)
945 if (this->rela_dyn_
== NULL
)
947 gold_assert(layout
!= NULL
);
948 this->rela_dyn_
= new Reloc_section(parameters
->options().combreloc());
949 layout
->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA
,
950 elfcpp::SHF_ALLOC
, this->rela_dyn_
,
951 ORDER_DYNAMIC_RELOCS
, false);
953 return this->rela_dyn_
;
956 // Get the section to use for IRELATIVE relocs, creating it if
957 // necessary. These go in .rela.dyn, but only after all other dynamic
958 // relocations. They need to follow the other dynamic relocations so
959 // that they can refer to global variables initialized by those
963 typename Target_x86_64
<size
>::Reloc_section
*
964 Target_x86_64
<size
>::rela_irelative_section(Layout
* layout
)
966 if (this->rela_irelative_
== NULL
)
968 // Make sure we have already created the dynamic reloc section.
969 this->rela_dyn_section(layout
);
970 this->rela_irelative_
= new Reloc_section(false);
971 layout
->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA
,
972 elfcpp::SHF_ALLOC
, this->rela_irelative_
,
973 ORDER_DYNAMIC_RELOCS
, false);
974 gold_assert(this->rela_dyn_
->output_section()
975 == this->rela_irelative_
->output_section());
977 return this->rela_irelative_
;
980 // Initialize the PLT section.
984 Output_data_plt_x86_64
<size
>::init(Layout
* layout
)
986 this->rel_
= new Reloc_section(false);
987 layout
->add_output_section_data(".rela.plt", elfcpp::SHT_RELA
,
988 elfcpp::SHF_ALLOC
, this->rel_
,
989 ORDER_DYNAMIC_PLT_RELOCS
, false);
991 // Add unwind information if requested.
992 if (parameters
->options().ld_generated_unwind_info())
993 layout
->add_eh_frame_for_plt(this, plt_eh_frame_cie
, plt_eh_frame_cie_size
,
994 plt_eh_frame_fde
, plt_eh_frame_fde_size
);
999 Output_data_plt_x86_64
<size
>::do_adjust_output_section(Output_section
* os
)
1001 os
->set_entsize(plt_entry_size
);
1004 // Add an entry to the PLT.
1008 Output_data_plt_x86_64
<size
>::add_entry(Symbol_table
* symtab
, Layout
* layout
,
1011 gold_assert(!gsym
->has_plt_offset());
1013 unsigned int plt_index
;
1015 section_offset_type got_offset
;
1017 unsigned int* pcount
;
1018 unsigned int offset
;
1019 unsigned int reserved
;
1020 Output_data_space
* got
;
1021 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
1022 && gsym
->can_use_relative_reloc(false))
1024 pcount
= &this->irelative_count_
;
1027 got
= this->got_irelative_
;
1031 pcount
= &this->count_
;
1034 got
= this->got_plt_
;
1037 if (!this->is_data_size_valid())
1039 // Note that when setting the PLT offset for a non-IRELATIVE
1040 // entry we skip the initial reserved PLT entry.
1041 plt_index
= *pcount
+ offset
;
1042 plt_offset
= plt_index
* plt_entry_size
;
1046 got_offset
= (plt_index
- offset
+ reserved
) * 8;
1047 gold_assert(got_offset
== got
->current_data_size());
1049 // Every PLT entry needs a GOT entry which points back to the PLT
1050 // entry (this will be changed by the dynamic linker, normally
1051 // lazily when the function is called).
1052 got
->set_current_data_size(got_offset
+ 8);
1056 // FIXME: This is probably not correct for IRELATIVE relocs.
1058 // For incremental updates, find an available slot.
1059 plt_offset
= this->free_list_
.allocate(plt_entry_size
, plt_entry_size
, 0);
1060 if (plt_offset
== -1)
1061 gold_fallback(_("out of patch space (PLT);"
1062 " relink with --incremental-full"));
1064 // The GOT and PLT entries have a 1-1 correspondance, so the GOT offset
1065 // can be calculated from the PLT index, adjusting for the three
1066 // reserved entries at the beginning of the GOT.
1067 plt_index
= plt_offset
/ plt_entry_size
- 1;
1068 got_offset
= (plt_index
- offset
+ reserved
) * 8;
1071 gsym
->set_plt_offset(plt_offset
);
1073 // Every PLT entry needs a reloc.
1074 this->add_relocation(symtab
, layout
, gsym
, got_offset
);
1076 // Note that we don't need to save the symbol. The contents of the
1077 // PLT are independent of which symbols are used. The symbols only
1078 // appear in the relocations.
1081 // Add an entry to the PLT for a local STT_GNU_IFUNC symbol. Return
1086 Output_data_plt_x86_64
<size
>::add_local_ifunc_entry(
1087 Symbol_table
* symtab
,
1089 Sized_relobj_file
<size
, false>* relobj
,
1090 unsigned int local_sym_index
)
1092 unsigned int plt_offset
= this->irelative_count_
* plt_entry_size
;
1093 ++this->irelative_count_
;
1095 section_offset_type got_offset
= this->got_irelative_
->current_data_size();
1097 // Every PLT entry needs a GOT entry which points back to the PLT
1099 this->got_irelative_
->set_current_data_size(got_offset
+ 8);
1101 // Every PLT entry needs a reloc.
1102 Reloc_section
* rela
= this->rela_irelative(symtab
, layout
);
1103 rela
->add_symbolless_local_addend(relobj
, local_sym_index
,
1104 elfcpp::R_X86_64_IRELATIVE
,
1105 this->got_irelative_
, got_offset
, 0);
1110 // Add the relocation for a PLT entry.
1114 Output_data_plt_x86_64
<size
>::add_relocation(Symbol_table
* symtab
,
1117 unsigned int got_offset
)
1119 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
1120 && gsym
->can_use_relative_reloc(false))
1122 Reloc_section
* rela
= this->rela_irelative(symtab
, layout
);
1123 rela
->add_symbolless_global_addend(gsym
, elfcpp::R_X86_64_IRELATIVE
,
1124 this->got_irelative_
, got_offset
, 0);
1128 gsym
->set_needs_dynsym_entry();
1129 this->rel_
->add_global(gsym
, elfcpp::R_X86_64_JUMP_SLOT
, this->got_plt_
,
1134 // Return where the TLSDESC relocations should go, creating it if
1135 // necessary. These follow the JUMP_SLOT relocations.
1138 typename Output_data_plt_x86_64
<size
>::Reloc_section
*
1139 Output_data_plt_x86_64
<size
>::rela_tlsdesc(Layout
* layout
)
1141 if (this->tlsdesc_rel_
== NULL
)
1143 this->tlsdesc_rel_
= new Reloc_section(false);
1144 layout
->add_output_section_data(".rela.plt", elfcpp::SHT_RELA
,
1145 elfcpp::SHF_ALLOC
, this->tlsdesc_rel_
,
1146 ORDER_DYNAMIC_PLT_RELOCS
, false);
1147 gold_assert(this->tlsdesc_rel_
->output_section()
1148 == this->rel_
->output_section());
1150 return this->tlsdesc_rel_
;
1153 // Return where the IRELATIVE relocations should go in the PLT. These
1154 // follow the JUMP_SLOT and the TLSDESC relocations.
1157 typename Output_data_plt_x86_64
<size
>::Reloc_section
*
1158 Output_data_plt_x86_64
<size
>::rela_irelative(Symbol_table
* symtab
,
1161 if (this->irelative_rel_
== NULL
)
1163 // Make sure we have a place for the TLSDESC relocations, in
1164 // case we see any later on.
1165 this->rela_tlsdesc(layout
);
1166 this->irelative_rel_
= new Reloc_section(false);
1167 layout
->add_output_section_data(".rela.plt", elfcpp::SHT_RELA
,
1168 elfcpp::SHF_ALLOC
, this->irelative_rel_
,
1169 ORDER_DYNAMIC_PLT_RELOCS
, false);
1170 gold_assert(this->irelative_rel_
->output_section()
1171 == this->rel_
->output_section());
1173 if (parameters
->doing_static_link())
1175 // A statically linked executable will only have a .rela.plt
1176 // section to hold R_X86_64_IRELATIVE relocs for
1177 // STT_GNU_IFUNC symbols. The library will use these
1178 // symbols to locate the IRELATIVE relocs at program startup
1180 symtab
->define_in_output_data("__rela_iplt_start", NULL
,
1181 Symbol_table::PREDEFINED
,
1182 this->irelative_rel_
, 0, 0,
1183 elfcpp::STT_NOTYPE
, elfcpp::STB_GLOBAL
,
1184 elfcpp::STV_HIDDEN
, 0, false, true);
1185 symtab
->define_in_output_data("__rela_iplt_end", NULL
,
1186 Symbol_table::PREDEFINED
,
1187 this->irelative_rel_
, 0, 0,
1188 elfcpp::STT_NOTYPE
, elfcpp::STB_GLOBAL
,
1189 elfcpp::STV_HIDDEN
, 0, true, true);
1192 return this->irelative_rel_
;
1195 // Return the PLT address to use for a global symbol.
1199 Output_data_plt_x86_64
<size
>::address_for_global(const Symbol
* gsym
)
1201 uint64_t offset
= 0;
1202 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
1203 && gsym
->can_use_relative_reloc(false))
1204 offset
= (this->count_
+ 1) * plt_entry_size
;
1205 return this->address() + offset
;
1208 // Return the PLT address to use for a local symbol. These are always
1209 // IRELATIVE relocs.
1213 Output_data_plt_x86_64
<size
>::address_for_local(const Relobj
*, unsigned int)
1215 return this->address() + (this->count_
+ 1) * plt_entry_size
;
1218 // Set the final size.
1221 Output_data_plt_x86_64
<size
>::set_final_data_size()
1223 unsigned int count
= this->count_
+ this->irelative_count_
;
1224 if (this->has_tlsdesc_entry())
1226 this->set_data_size((count
+ 1) * plt_entry_size
);
1229 // The first entry in the PLT for an executable.
1233 Output_data_plt_x86_64
<size
>::first_plt_entry
[plt_entry_size
] =
1235 // From AMD64 ABI Draft 0.98, page 76
1236 0xff, 0x35, // pushq contents of memory address
1237 0, 0, 0, 0, // replaced with address of .got + 8
1238 0xff, 0x25, // jmp indirect
1239 0, 0, 0, 0, // replaced with address of .got + 16
1240 0x90, 0x90, 0x90, 0x90 // noop (x4)
1243 // Subsequent entries in the PLT for an executable.
1247 Output_data_plt_x86_64
<size
>::plt_entry
[plt_entry_size
] =
1249 // From AMD64 ABI Draft 0.98, page 76
1250 0xff, 0x25, // jmpq indirect
1251 0, 0, 0, 0, // replaced with address of symbol in .got
1252 0x68, // pushq immediate
1253 0, 0, 0, 0, // replaced with offset into relocation table
1254 0xe9, // jmpq relative
1255 0, 0, 0, 0 // replaced with offset to start of .plt
1258 // The reserved TLSDESC entry in the PLT for an executable.
1262 Output_data_plt_x86_64
<size
>::tlsdesc_plt_entry
[plt_entry_size
] =
1264 // From Alexandre Oliva, "Thread-Local Storage Descriptors for IA32
1265 // and AMD64/EM64T", Version 0.9.4 (2005-10-10).
1266 0xff, 0x35, // pushq x(%rip)
1267 0, 0, 0, 0, // replaced with address of linkmap GOT entry (at PLTGOT + 8)
1268 0xff, 0x25, // jmpq *y(%rip)
1269 0, 0, 0, 0, // replaced with offset of reserved TLSDESC_GOT entry
1274 // The .eh_frame unwind information for the PLT.
1278 Output_data_plt_x86_64
<size
>::plt_eh_frame_cie
[plt_eh_frame_cie_size
] =
1281 'z', // Augmentation: augmentation size included.
1282 'R', // Augmentation: FDE encoding included.
1283 '\0', // End of augmentation string.
1284 1, // Code alignment factor.
1285 0x78, // Data alignment factor.
1286 16, // Return address column.
1287 1, // Augmentation size.
1288 (elfcpp::DW_EH_PE_pcrel
// FDE encoding.
1289 | elfcpp::DW_EH_PE_sdata4
),
1290 elfcpp::DW_CFA_def_cfa
, 7, 8, // DW_CFA_def_cfa: r7 (rsp) ofs 8.
1291 elfcpp::DW_CFA_offset
+ 16, 1,// DW_CFA_offset: r16 (rip) at cfa-8.
1292 elfcpp::DW_CFA_nop
, // Align to 16 bytes.
1298 Output_data_plt_x86_64
<size
>::plt_eh_frame_fde
[plt_eh_frame_fde_size
] =
1300 0, 0, 0, 0, // Replaced with offset to .plt.
1301 0, 0, 0, 0, // Replaced with size of .plt.
1302 0, // Augmentation size.
1303 elfcpp::DW_CFA_def_cfa_offset
, 16, // DW_CFA_def_cfa_offset: 16.
1304 elfcpp::DW_CFA_advance_loc
+ 6, // Advance 6 to __PLT__ + 6.
1305 elfcpp::DW_CFA_def_cfa_offset
, 24, // DW_CFA_def_cfa_offset: 24.
1306 elfcpp::DW_CFA_advance_loc
+ 10, // Advance 10 to __PLT__ + 16.
1307 elfcpp::DW_CFA_def_cfa_expression
, // DW_CFA_def_cfa_expression.
1308 11, // Block length.
1309 elfcpp::DW_OP_breg7
, 8, // Push %rsp + 8.
1310 elfcpp::DW_OP_breg16
, 0, // Push %rip.
1311 elfcpp::DW_OP_lit15
, // Push 0xf.
1312 elfcpp::DW_OP_and
, // & (%rip & 0xf).
1313 elfcpp::DW_OP_lit11
, // Push 0xb.
1314 elfcpp::DW_OP_ge
, // >= ((%rip & 0xf) >= 0xb)
1315 elfcpp::DW_OP_lit3
, // Push 3.
1316 elfcpp::DW_OP_shl
, // << (((%rip & 0xf) >= 0xb) << 3)
1317 elfcpp::DW_OP_plus
, // + ((((%rip&0xf)>=0xb)<<3)+%rsp+8
1318 elfcpp::DW_CFA_nop
, // Align to 32 bytes.
1324 // Write out the PLT. This uses the hand-coded instructions above,
1325 // and adjusts them as needed. This is specified by the AMD64 ABI.
1329 Output_data_plt_x86_64
<size
>::do_write(Output_file
* of
)
1331 const off_t offset
= this->offset();
1332 const section_size_type oview_size
=
1333 convert_to_section_size_type(this->data_size());
1334 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
1336 const off_t got_file_offset
= this->got_plt_
->offset();
1337 gold_assert(parameters
->incremental_update()
1338 || (got_file_offset
+ this->got_plt_
->data_size()
1339 == this->got_irelative_
->offset()));
1340 const section_size_type got_size
=
1341 convert_to_section_size_type(this->got_plt_
->data_size()
1342 + this->got_irelative_
->data_size());
1343 unsigned char* const got_view
= of
->get_output_view(got_file_offset
,
1346 unsigned char* pov
= oview
;
1348 // The base address of the .plt section.
1349 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
= this->address();
1350 // The base address of the .got section.
1351 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_base
= this->got_
->address();
1352 // The base address of the PLT portion of the .got section,
1353 // which is where the GOT pointer will point, and where the
1354 // three reserved GOT entries are located.
1355 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
1356 = this->got_plt_
->address();
1358 memcpy(pov
, first_plt_entry
, plt_entry_size
);
1359 // We do a jmp relative to the PC at the end of this instruction.
1360 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
1362 - (plt_address
+ 6)));
1363 elfcpp::Swap
<32, false>::writeval(pov
+ 8,
1365 - (plt_address
+ 12)));
1366 pov
+= plt_entry_size
;
1368 unsigned char* got_pov
= got_view
;
1370 // The first entry in the GOT is the address of the .dynamic section
1371 // aka the PT_DYNAMIC segment. The next two entries are reserved.
1372 // We saved space for them when we created the section in
1373 // Target_x86_64::got_section.
1374 Output_section
* dynamic
= this->layout_
->dynamic_section();
1375 uint32_t dynamic_addr
= dynamic
== NULL
? 0 : dynamic
->address();
1376 elfcpp::Swap
<64, false>::writeval(got_pov
, dynamic_addr
);
1378 memset(got_pov
, 0, 16);
1381 unsigned int plt_offset
= plt_entry_size
;
1382 unsigned int got_offset
= 24;
1383 const unsigned int count
= this->count_
+ this->irelative_count_
;
1384 for (unsigned int plt_index
= 0;
1387 pov
+= plt_entry_size
,
1389 plt_offset
+= plt_entry_size
,
1392 // Set and adjust the PLT entry itself.
1393 memcpy(pov
, plt_entry
, plt_entry_size
);
1394 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
1395 (got_address
+ got_offset
1396 - (plt_address
+ plt_offset
1399 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 7, plt_index
);
1400 elfcpp::Swap
<32, false>::writeval(pov
+ 12,
1401 - (plt_offset
+ plt_entry_size
));
1403 // Set the entry in the GOT.
1404 elfcpp::Swap
<64, false>::writeval(got_pov
, plt_address
+ plt_offset
+ 6);
1407 if (this->has_tlsdesc_entry())
1409 // Set and adjust the reserved TLSDESC PLT entry.
1410 unsigned int tlsdesc_got_offset
= this->get_tlsdesc_got_offset();
1411 memcpy(pov
, tlsdesc_plt_entry
, plt_entry_size
);
1412 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
1414 - (plt_address
+ plt_offset
1416 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 8,
1418 + tlsdesc_got_offset
1419 - (plt_address
+ plt_offset
1421 pov
+= plt_entry_size
;
1424 gold_assert(static_cast<section_size_type
>(pov
- oview
) == oview_size
);
1425 gold_assert(static_cast<section_size_type
>(got_pov
- got_view
) == got_size
);
1427 of
->write_output_view(offset
, oview_size
, oview
);
1428 of
->write_output_view(got_file_offset
, got_size
, got_view
);
1431 // Create the PLT section.
1435 Target_x86_64
<size
>::make_plt_section(Symbol_table
* symtab
, Layout
* layout
)
1437 if (this->plt_
== NULL
)
1439 // Create the GOT sections first.
1440 this->got_section(symtab
, layout
);
1442 this->plt_
= new Output_data_plt_x86_64
<size
>(layout
, this->got_
,
1444 this->got_irelative_
);
1445 layout
->add_output_section_data(".plt", elfcpp::SHT_PROGBITS
,
1447 | elfcpp::SHF_EXECINSTR
),
1448 this->plt_
, ORDER_PLT
, false);
1450 // Make the sh_info field of .rela.plt point to .plt.
1451 Output_section
* rela_plt_os
= this->plt_
->rela_plt()->output_section();
1452 rela_plt_os
->set_info_section(this->plt_
->output_section());
1456 // Return the section for TLSDESC relocations.
1459 typename Target_x86_64
<size
>::Reloc_section
*
1460 Target_x86_64
<size
>::rela_tlsdesc_section(Layout
* layout
) const
1462 return this->plt_section()->rela_tlsdesc(layout
);
1465 // Create a PLT entry for a global symbol.
1469 Target_x86_64
<size
>::make_plt_entry(Symbol_table
* symtab
, Layout
* layout
,
1472 if (gsym
->has_plt_offset())
1475 if (this->plt_
== NULL
)
1476 this->make_plt_section(symtab
, layout
);
1478 this->plt_
->add_entry(symtab
, layout
, gsym
);
1481 // Make a PLT entry for a local STT_GNU_IFUNC symbol.
1485 Target_x86_64
<size
>::make_local_ifunc_plt_entry(
1486 Symbol_table
* symtab
, Layout
* layout
,
1487 Sized_relobj_file
<size
, false>* relobj
,
1488 unsigned int local_sym_index
)
1490 if (relobj
->local_has_plt_offset(local_sym_index
))
1492 if (this->plt_
== NULL
)
1493 this->make_plt_section(symtab
, layout
);
1494 unsigned int plt_offset
= this->plt_
->add_local_ifunc_entry(symtab
, layout
,
1497 relobj
->set_local_plt_offset(local_sym_index
, plt_offset
);
1500 // Return the number of entries in the PLT.
1504 Target_x86_64
<size
>::plt_entry_count() const
1506 if (this->plt_
== NULL
)
1508 return this->plt_
->entry_count();
1511 // Return the offset of the first non-reserved PLT entry.
1515 Target_x86_64
<size
>::first_plt_entry_offset() const
1517 return Output_data_plt_x86_64
<size
>::first_plt_entry_offset();
1520 // Return the size of each PLT entry.
1524 Target_x86_64
<size
>::plt_entry_size() const
1526 return Output_data_plt_x86_64
<size
>::get_plt_entry_size();
1529 // Create the GOT and PLT sections for an incremental update.
1532 Output_data_got_base
*
1533 Target_x86_64
<size
>::init_got_plt_for_update(Symbol_table
* symtab
,
1535 unsigned int got_count
,
1536 unsigned int plt_count
)
1538 gold_assert(this->got_
== NULL
);
1540 this->got_
= new Output_data_got
<64, false>(got_count
* 8);
1541 layout
->add_output_section_data(".got", elfcpp::SHT_PROGBITS
,
1543 | elfcpp::SHF_WRITE
),
1544 this->got_
, ORDER_RELRO_LAST
,
1547 // Add the three reserved entries.
1548 this->got_plt_
= new Output_data_space((plt_count
+ 3) * 8, 8, "** GOT PLT");
1549 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
1551 | elfcpp::SHF_WRITE
),
1552 this->got_plt_
, ORDER_NON_RELRO_FIRST
,
1555 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
1556 this->global_offset_table_
=
1557 symtab
->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL
,
1558 Symbol_table::PREDEFINED
,
1560 0, 0, elfcpp::STT_OBJECT
,
1562 elfcpp::STV_HIDDEN
, 0,
1565 // If there are any TLSDESC relocations, they get GOT entries in
1566 // .got.plt after the jump slot entries.
1567 // FIXME: Get the count for TLSDESC entries.
1568 this->got_tlsdesc_
= new Output_data_got
<64, false>(0);
1569 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
1570 elfcpp::SHF_ALLOC
| elfcpp::SHF_WRITE
,
1572 ORDER_NON_RELRO_FIRST
, false);
1574 // If there are any IRELATIVE relocations, they get GOT entries in
1575 // .got.plt after the jump slot and TLSDESC entries.
1576 this->got_irelative_
= new Output_data_space(0, 8, "** GOT IRELATIVE PLT");
1577 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
1578 elfcpp::SHF_ALLOC
| elfcpp::SHF_WRITE
,
1579 this->got_irelative_
,
1580 ORDER_NON_RELRO_FIRST
, false);
1582 // Create the PLT section.
1583 this->plt_
= new Output_data_plt_x86_64
<size
>(layout
, this->got_
,
1585 this->got_irelative_
,
1587 layout
->add_output_section_data(".plt", elfcpp::SHT_PROGBITS
,
1588 elfcpp::SHF_ALLOC
| elfcpp::SHF_EXECINSTR
,
1589 this->plt_
, ORDER_PLT
, false);
1591 // Make the sh_info field of .rela.plt point to .plt.
1592 Output_section
* rela_plt_os
= this->plt_
->rela_plt()->output_section();
1593 rela_plt_os
->set_info_section(this->plt_
->output_section());
1595 // Create the rela_dyn section.
1596 this->rela_dyn_section(layout
);
1601 // Reserve a GOT entry for a local symbol, and regenerate any
1602 // necessary dynamic relocations.
1606 Target_x86_64
<size
>::reserve_local_got_entry(
1607 unsigned int got_index
,
1608 Sized_relobj
<size
, false>* obj
,
1610 unsigned int got_type
)
1612 unsigned int got_offset
= got_index
* 8;
1613 Reloc_section
* rela_dyn
= this->rela_dyn_section(NULL
);
1615 this->got_
->reserve_local(got_index
, obj
, r_sym
, got_type
);
1618 case GOT_TYPE_STANDARD
:
1619 if (parameters
->options().output_is_position_independent())
1620 rela_dyn
->add_local_relative(obj
, r_sym
, elfcpp::R_X86_64_RELATIVE
,
1621 this->got_
, got_offset
, 0, false);
1623 case GOT_TYPE_TLS_OFFSET
:
1624 rela_dyn
->add_local(obj
, r_sym
, elfcpp::R_X86_64_TPOFF64
,
1625 this->got_
, got_offset
, 0);
1627 case GOT_TYPE_TLS_PAIR
:
1628 this->got_
->reserve_slot(got_index
+ 1);
1629 rela_dyn
->add_local(obj
, r_sym
, elfcpp::R_X86_64_DTPMOD64
,
1630 this->got_
, got_offset
, 0);
1632 case GOT_TYPE_TLS_DESC
:
1633 gold_fatal(_("TLS_DESC not yet supported for incremental linking"));
1634 // this->got_->reserve_slot(got_index + 1);
1635 // rela_dyn->add_target_specific(elfcpp::R_X86_64_TLSDESC, arg,
1636 // this->got_, got_offset, 0);
1643 // Reserve a GOT entry for a global symbol, and regenerate any
1644 // necessary dynamic relocations.
1648 Target_x86_64
<size
>::reserve_global_got_entry(unsigned int got_index
,
1650 unsigned int got_type
)
1652 unsigned int got_offset
= got_index
* 8;
1653 Reloc_section
* rela_dyn
= this->rela_dyn_section(NULL
);
1655 this->got_
->reserve_global(got_index
, gsym
, got_type
);
1658 case GOT_TYPE_STANDARD
:
1659 if (!gsym
->final_value_is_known())
1661 if (gsym
->is_from_dynobj()
1662 || gsym
->is_undefined()
1663 || gsym
->is_preemptible()
1664 || gsym
->type() == elfcpp::STT_GNU_IFUNC
)
1665 rela_dyn
->add_global(gsym
, elfcpp::R_X86_64_GLOB_DAT
,
1666 this->got_
, got_offset
, 0);
1668 rela_dyn
->add_global_relative(gsym
, elfcpp::R_X86_64_RELATIVE
,
1669 this->got_
, got_offset
, 0);
1672 case GOT_TYPE_TLS_OFFSET
:
1673 rela_dyn
->add_global_relative(gsym
, elfcpp::R_X86_64_TPOFF64
,
1674 this->got_
, got_offset
, 0);
1676 case GOT_TYPE_TLS_PAIR
:
1677 this->got_
->reserve_slot(got_index
+ 1);
1678 rela_dyn
->add_global_relative(gsym
, elfcpp::R_X86_64_DTPMOD64
,
1679 this->got_
, got_offset
, 0);
1680 rela_dyn
->add_global_relative(gsym
, elfcpp::R_X86_64_DTPOFF64
,
1681 this->got_
, got_offset
+ 8, 0);
1683 case GOT_TYPE_TLS_DESC
:
1684 this->got_
->reserve_slot(got_index
+ 1);
1685 rela_dyn
->add_global_relative(gsym
, elfcpp::R_X86_64_TLSDESC
,
1686 this->got_
, got_offset
, 0);
1693 // Register an existing PLT entry for a global symbol.
1697 Target_x86_64
<size
>::register_global_plt_entry(Symbol_table
* symtab
,
1699 unsigned int plt_index
,
1702 gold_assert(this->plt_
!= NULL
);
1703 gold_assert(!gsym
->has_plt_offset());
1705 this->plt_
->reserve_slot(plt_index
);
1707 gsym
->set_plt_offset((plt_index
+ 1) * this->plt_entry_size());
1709 unsigned int got_offset
= (plt_index
+ 3) * 8;
1710 this->plt_
->add_relocation(symtab
, layout
, gsym
, got_offset
);
1713 // Force a COPY relocation for a given symbol.
1717 Target_x86_64
<size
>::emit_copy_reloc(
1718 Symbol_table
* symtab
, Symbol
* sym
, Output_section
* os
, off_t offset
)
1720 this->copy_relocs_
.emit_copy_reloc(symtab
,
1721 symtab
->get_sized_symbol
<size
>(sym
),
1724 this->rela_dyn_section(NULL
));
1727 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
1731 Target_x86_64
<size
>::define_tls_base_symbol(Symbol_table
* symtab
,
1734 if (this->tls_base_symbol_defined_
)
1737 Output_segment
* tls_segment
= layout
->tls_segment();
1738 if (tls_segment
!= NULL
)
1740 bool is_exec
= parameters
->options().output_is_executable();
1741 symtab
->define_in_output_segment("_TLS_MODULE_BASE_", NULL
,
1742 Symbol_table::PREDEFINED
,
1746 elfcpp::STV_HIDDEN
, 0,
1748 ? Symbol::SEGMENT_END
1749 : Symbol::SEGMENT_START
),
1752 this->tls_base_symbol_defined_
= true;
1755 // Create the reserved PLT and GOT entries for the TLS descriptor resolver.
1759 Target_x86_64
<size
>::reserve_tlsdesc_entries(Symbol_table
* symtab
,
1762 if (this->plt_
== NULL
)
1763 this->make_plt_section(symtab
, layout
);
1765 if (!this->plt_
->has_tlsdesc_entry())
1767 // Allocate the TLSDESC_GOT entry.
1768 Output_data_got
<64, false>* got
= this->got_section(symtab
, layout
);
1769 unsigned int got_offset
= got
->add_constant(0);
1771 // Allocate the TLSDESC_PLT entry.
1772 this->plt_
->reserve_tlsdesc_entry(got_offset
);
1776 // Create a GOT entry for the TLS module index.
1780 Target_x86_64
<size
>::got_mod_index_entry(Symbol_table
* symtab
, Layout
* layout
,
1781 Sized_relobj_file
<size
, false>* object
)
1783 if (this->got_mod_index_offset_
== -1U)
1785 gold_assert(symtab
!= NULL
&& layout
!= NULL
&& object
!= NULL
);
1786 Reloc_section
* rela_dyn
= this->rela_dyn_section(layout
);
1787 Output_data_got
<64, false>* got
= this->got_section(symtab
, layout
);
1788 unsigned int got_offset
= got
->add_constant(0);
1789 rela_dyn
->add_local(object
, 0, elfcpp::R_X86_64_DTPMOD64
, got
,
1791 got
->add_constant(0);
1792 this->got_mod_index_offset_
= got_offset
;
1794 return this->got_mod_index_offset_
;
1797 // Optimize the TLS relocation type based on what we know about the
1798 // symbol. IS_FINAL is true if the final address of this symbol is
1799 // known at link time.
1802 tls::Tls_optimization
1803 Target_x86_64
<size
>::optimize_tls_reloc(bool is_final
, int r_type
)
1805 // If we are generating a shared library, then we can't do anything
1807 if (parameters
->options().shared())
1808 return tls::TLSOPT_NONE
;
1812 case elfcpp::R_X86_64_TLSGD
:
1813 case elfcpp::R_X86_64_GOTPC32_TLSDESC
:
1814 case elfcpp::R_X86_64_TLSDESC_CALL
:
1815 // These are General-Dynamic which permits fully general TLS
1816 // access. Since we know that we are generating an executable,
1817 // we can convert this to Initial-Exec. If we also know that
1818 // this is a local symbol, we can further switch to Local-Exec.
1820 return tls::TLSOPT_TO_LE
;
1821 return tls::TLSOPT_TO_IE
;
1823 case elfcpp::R_X86_64_TLSLD
:
1824 // This is Local-Dynamic, which refers to a local symbol in the
1825 // dynamic TLS block. Since we know that we generating an
1826 // executable, we can switch to Local-Exec.
1827 return tls::TLSOPT_TO_LE
;
1829 case elfcpp::R_X86_64_DTPOFF32
:
1830 case elfcpp::R_X86_64_DTPOFF64
:
1831 // Another Local-Dynamic reloc.
1832 return tls::TLSOPT_TO_LE
;
1834 case elfcpp::R_X86_64_GOTTPOFF
:
1835 // These are Initial-Exec relocs which get the thread offset
1836 // from the GOT. If we know that we are linking against the
1837 // local symbol, we can switch to Local-Exec, which links the
1838 // thread offset into the instruction.
1840 return tls::TLSOPT_TO_LE
;
1841 return tls::TLSOPT_NONE
;
1843 case elfcpp::R_X86_64_TPOFF32
:
1844 // When we already have Local-Exec, there is nothing further we
1846 return tls::TLSOPT_NONE
;
1853 // Get the Reference_flags for a particular relocation.
1857 Target_x86_64
<size
>::Scan::get_reference_flags(unsigned int r_type
)
1861 case elfcpp::R_X86_64_NONE
:
1862 case elfcpp::R_X86_64_GNU_VTINHERIT
:
1863 case elfcpp::R_X86_64_GNU_VTENTRY
:
1864 case elfcpp::R_X86_64_GOTPC32
:
1865 case elfcpp::R_X86_64_GOTPC64
:
1866 // No symbol reference.
1869 case elfcpp::R_X86_64_64
:
1870 case elfcpp::R_X86_64_32
:
1871 case elfcpp::R_X86_64_32S
:
1872 case elfcpp::R_X86_64_16
:
1873 case elfcpp::R_X86_64_8
:
1874 return Symbol::ABSOLUTE_REF
;
1876 case elfcpp::R_X86_64_PC64
:
1877 case elfcpp::R_X86_64_PC32
:
1878 case elfcpp::R_X86_64_PC16
:
1879 case elfcpp::R_X86_64_PC8
:
1880 case elfcpp::R_X86_64_GOTOFF64
:
1881 return Symbol::RELATIVE_REF
;
1883 case elfcpp::R_X86_64_PLT32
:
1884 case elfcpp::R_X86_64_PLTOFF64
:
1885 return Symbol::FUNCTION_CALL
| Symbol::RELATIVE_REF
;
1887 case elfcpp::R_X86_64_GOT64
:
1888 case elfcpp::R_X86_64_GOT32
:
1889 case elfcpp::R_X86_64_GOTPCREL64
:
1890 case elfcpp::R_X86_64_GOTPCREL
:
1891 case elfcpp::R_X86_64_GOTPLT64
:
1893 return Symbol::ABSOLUTE_REF
;
1895 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
1896 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
1897 case elfcpp::R_X86_64_TLSDESC_CALL
:
1898 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
1899 case elfcpp::R_X86_64_DTPOFF32
:
1900 case elfcpp::R_X86_64_DTPOFF64
:
1901 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
1902 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
1903 return Symbol::TLS_REF
;
1905 case elfcpp::R_X86_64_COPY
:
1906 case elfcpp::R_X86_64_GLOB_DAT
:
1907 case elfcpp::R_X86_64_JUMP_SLOT
:
1908 case elfcpp::R_X86_64_RELATIVE
:
1909 case elfcpp::R_X86_64_IRELATIVE
:
1910 case elfcpp::R_X86_64_TPOFF64
:
1911 case elfcpp::R_X86_64_DTPMOD64
:
1912 case elfcpp::R_X86_64_TLSDESC
:
1913 case elfcpp::R_X86_64_SIZE32
:
1914 case elfcpp::R_X86_64_SIZE64
:
1916 // Not expected. We will give an error later.
1921 // Report an unsupported relocation against a local symbol.
1925 Target_x86_64
<size
>::Scan::unsupported_reloc_local(
1926 Sized_relobj_file
<size
, false>* object
,
1927 unsigned int r_type
)
1929 gold_error(_("%s: unsupported reloc %u against local symbol"),
1930 object
->name().c_str(), r_type
);
1933 // We are about to emit a dynamic relocation of type R_TYPE. If the
1934 // dynamic linker does not support it, issue an error. The GNU linker
1935 // only issues a non-PIC error for an allocated read-only section.
1936 // Here we know the section is allocated, but we don't know that it is
1937 // read-only. But we check for all the relocation types which the
1938 // glibc dynamic linker supports, so it seems appropriate to issue an
1939 // error even if the section is not read-only. If GSYM is not NULL,
1940 // it is the symbol the relocation is against; if it is NULL, the
1941 // relocation is against a local symbol.
1945 Target_x86_64
<size
>::Scan::check_non_pic(Relobj
* object
, unsigned int r_type
,
1950 // These are the relocation types supported by glibc for x86_64
1951 // which should always work.
1952 case elfcpp::R_X86_64_RELATIVE
:
1953 case elfcpp::R_X86_64_IRELATIVE
:
1954 case elfcpp::R_X86_64_GLOB_DAT
:
1955 case elfcpp::R_X86_64_JUMP_SLOT
:
1956 case elfcpp::R_X86_64_DTPMOD64
:
1957 case elfcpp::R_X86_64_DTPOFF64
:
1958 case elfcpp::R_X86_64_TPOFF64
:
1959 case elfcpp::R_X86_64_64
:
1960 case elfcpp::R_X86_64_COPY
:
1963 // glibc supports these reloc types, but they can overflow.
1964 case elfcpp::R_X86_64_PC32
:
1965 // A PC relative reference is OK against a local symbol or if
1966 // the symbol is defined locally.
1968 || (!gsym
->is_from_dynobj()
1969 && !gsym
->is_undefined()
1970 && !gsym
->is_preemptible()))
1973 case elfcpp::R_X86_64_32
:
1974 if (this->issued_non_pic_error_
)
1976 gold_assert(parameters
->options().output_is_position_independent());
1978 object
->error(_("requires dynamic R_X86_64_32 reloc which may "
1979 "overflow at runtime; recompile with -fPIC"));
1981 object
->error(_("requires dynamic %s reloc against '%s' which may "
1982 "overflow at runtime; recompile with -fPIC"),
1983 (r_type
== elfcpp::R_X86_64_32
1987 this->issued_non_pic_error_
= true;
1991 // This prevents us from issuing more than one error per reloc
1992 // section. But we can still wind up issuing more than one
1993 // error per object file.
1994 if (this->issued_non_pic_error_
)
1996 gold_assert(parameters
->options().output_is_position_independent());
1997 object
->error(_("requires unsupported dynamic reloc %u; "
1998 "recompile with -fPIC"),
2000 this->issued_non_pic_error_
= true;
2003 case elfcpp::R_X86_64_NONE
:
2008 // Return whether we need to make a PLT entry for a relocation of the
2009 // given type against a STT_GNU_IFUNC symbol.
2013 Target_x86_64
<size
>::Scan::reloc_needs_plt_for_ifunc(
2014 Sized_relobj_file
<size
, false>* object
,
2015 unsigned int r_type
)
2017 int flags
= Scan::get_reference_flags(r_type
);
2018 if (flags
& Symbol::TLS_REF
)
2019 gold_error(_("%s: unsupported TLS reloc %u for IFUNC symbol"),
2020 object
->name().c_str(), r_type
);
2024 // Scan a relocation for a local symbol.
2028 Target_x86_64
<size
>::Scan::local(Symbol_table
* symtab
,
2030 Target_x86_64
<size
>* target
,
2031 Sized_relobj_file
<size
, false>* object
,
2032 unsigned int data_shndx
,
2033 Output_section
* output_section
,
2034 const elfcpp::Rela
<size
, false>& reloc
,
2035 unsigned int r_type
,
2036 const elfcpp::Sym
<size
, false>& lsym
)
2038 // A local STT_GNU_IFUNC symbol may require a PLT entry.
2039 bool is_ifunc
= lsym
.get_st_type() == elfcpp::STT_GNU_IFUNC
;
2040 if (is_ifunc
&& this->reloc_needs_plt_for_ifunc(object
, r_type
))
2042 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(reloc
.get_r_info());
2043 target
->make_local_ifunc_plt_entry(symtab
, layout
, object
, r_sym
);
2048 case elfcpp::R_X86_64_NONE
:
2049 case elfcpp::R_X86_64_GNU_VTINHERIT
:
2050 case elfcpp::R_X86_64_GNU_VTENTRY
:
2053 case elfcpp::R_X86_64_64
:
2054 // If building a shared library (or a position-independent
2055 // executable), we need to create a dynamic relocation for this
2056 // location. The relocation applied at link time will apply the
2057 // link-time value, so we flag the location with an
2058 // R_X86_64_RELATIVE relocation so the dynamic loader can
2059 // relocate it easily.
2060 if (parameters
->options().output_is_position_independent())
2062 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(reloc
.get_r_info());
2063 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
2064 rela_dyn
->add_local_relative(object
, r_sym
,
2065 elfcpp::R_X86_64_RELATIVE
,
2066 output_section
, data_shndx
,
2067 reloc
.get_r_offset(),
2068 reloc
.get_r_addend(), is_ifunc
);
2072 case elfcpp::R_X86_64_32
:
2073 case elfcpp::R_X86_64_32S
:
2074 case elfcpp::R_X86_64_16
:
2075 case elfcpp::R_X86_64_8
:
2076 // If building a shared library (or a position-independent
2077 // executable), we need to create a dynamic relocation for this
2078 // location. We can't use an R_X86_64_RELATIVE relocation
2079 // because that is always a 64-bit relocation.
2080 if (parameters
->options().output_is_position_independent())
2082 this->check_non_pic(object
, r_type
, NULL
);
2084 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
2085 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(reloc
.get_r_info());
2086 if (lsym
.get_st_type() != elfcpp::STT_SECTION
)
2087 rela_dyn
->add_local(object
, r_sym
, r_type
, output_section
,
2088 data_shndx
, reloc
.get_r_offset(),
2089 reloc
.get_r_addend());
2092 gold_assert(lsym
.get_st_value() == 0);
2093 unsigned int shndx
= lsym
.get_st_shndx();
2095 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
,
2098 object
->error(_("section symbol %u has bad shndx %u"),
2101 rela_dyn
->add_local_section(object
, shndx
,
2102 r_type
, output_section
,
2103 data_shndx
, reloc
.get_r_offset(),
2104 reloc
.get_r_addend());
2109 case elfcpp::R_X86_64_PC64
:
2110 case elfcpp::R_X86_64_PC32
:
2111 case elfcpp::R_X86_64_PC16
:
2112 case elfcpp::R_X86_64_PC8
:
2115 case elfcpp::R_X86_64_PLT32
:
2116 // Since we know this is a local symbol, we can handle this as a
2120 case elfcpp::R_X86_64_GOTPC32
:
2121 case elfcpp::R_X86_64_GOTOFF64
:
2122 case elfcpp::R_X86_64_GOTPC64
:
2123 case elfcpp::R_X86_64_PLTOFF64
:
2124 // We need a GOT section.
2125 target
->got_section(symtab
, layout
);
2126 // For PLTOFF64, we'd normally want a PLT section, but since we
2127 // know this is a local symbol, no PLT is needed.
2130 case elfcpp::R_X86_64_GOT64
:
2131 case elfcpp::R_X86_64_GOT32
:
2132 case elfcpp::R_X86_64_GOTPCREL64
:
2133 case elfcpp::R_X86_64_GOTPCREL
:
2134 case elfcpp::R_X86_64_GOTPLT64
:
2136 // The symbol requires a GOT entry.
2137 Output_data_got
<64, false>* got
= target
->got_section(symtab
, layout
);
2138 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(reloc
.get_r_info());
2140 // For a STT_GNU_IFUNC symbol we want the PLT offset. That
2141 // lets function pointers compare correctly with shared
2142 // libraries. Otherwise we would need an IRELATIVE reloc.
2145 is_new
= got
->add_local_plt(object
, r_sym
, GOT_TYPE_STANDARD
);
2147 is_new
= got
->add_local(object
, r_sym
, GOT_TYPE_STANDARD
);
2150 // If we are generating a shared object, we need to add a
2151 // dynamic relocation for this symbol's GOT entry.
2152 if (parameters
->options().output_is_position_independent())
2154 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
2155 // R_X86_64_RELATIVE assumes a 64-bit relocation.
2156 if (r_type
!= elfcpp::R_X86_64_GOT32
)
2158 unsigned int got_offset
=
2159 object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
);
2160 rela_dyn
->add_local_relative(object
, r_sym
,
2161 elfcpp::R_X86_64_RELATIVE
,
2162 got
, got_offset
, 0, is_ifunc
);
2166 this->check_non_pic(object
, r_type
, NULL
);
2168 gold_assert(lsym
.get_st_type() != elfcpp::STT_SECTION
);
2169 rela_dyn
->add_local(
2170 object
, r_sym
, r_type
, got
,
2171 object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
), 0);
2175 // For GOTPLT64, we'd normally want a PLT section, but since
2176 // we know this is a local symbol, no PLT is needed.
2180 case elfcpp::R_X86_64_COPY
:
2181 case elfcpp::R_X86_64_GLOB_DAT
:
2182 case elfcpp::R_X86_64_JUMP_SLOT
:
2183 case elfcpp::R_X86_64_RELATIVE
:
2184 case elfcpp::R_X86_64_IRELATIVE
:
2185 // These are outstanding tls relocs, which are unexpected when linking
2186 case elfcpp::R_X86_64_TPOFF64
:
2187 case elfcpp::R_X86_64_DTPMOD64
:
2188 case elfcpp::R_X86_64_TLSDESC
:
2189 gold_error(_("%s: unexpected reloc %u in object file"),
2190 object
->name().c_str(), r_type
);
2193 // These are initial tls relocs, which are expected when linking
2194 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
2195 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
2196 case elfcpp::R_X86_64_TLSDESC_CALL
:
2197 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
2198 case elfcpp::R_X86_64_DTPOFF32
:
2199 case elfcpp::R_X86_64_DTPOFF64
:
2200 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
2201 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
2203 bool output_is_shared
= parameters
->options().shared();
2204 const tls::Tls_optimization optimized_type
2205 = Target_x86_64
<size
>::optimize_tls_reloc(!output_is_shared
,
2209 case elfcpp::R_X86_64_TLSGD
: // General-dynamic
2210 if (optimized_type
== tls::TLSOPT_NONE
)
2212 // Create a pair of GOT entries for the module index and
2213 // dtv-relative offset.
2214 Output_data_got
<64, false>* got
2215 = target
->got_section(symtab
, layout
);
2216 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(reloc
.get_r_info());
2217 unsigned int shndx
= lsym
.get_st_shndx();
2219 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
, &is_ordinary
);
2221 object
->error(_("local symbol %u has bad shndx %u"),
2224 got
->add_local_pair_with_rel(object
, r_sym
,
2227 target
->rela_dyn_section(layout
),
2228 elfcpp::R_X86_64_DTPMOD64
, 0);
2230 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2231 unsupported_reloc_local(object
, r_type
);
2234 case elfcpp::R_X86_64_GOTPC32_TLSDESC
:
2235 target
->define_tls_base_symbol(symtab
, layout
);
2236 if (optimized_type
== tls::TLSOPT_NONE
)
2238 // Create reserved PLT and GOT entries for the resolver.
2239 target
->reserve_tlsdesc_entries(symtab
, layout
);
2241 // Generate a double GOT entry with an
2242 // R_X86_64_TLSDESC reloc. The R_X86_64_TLSDESC reloc
2243 // is resolved lazily, so the GOT entry needs to be in
2244 // an area in .got.plt, not .got. Call got_section to
2245 // make sure the section has been created.
2246 target
->got_section(symtab
, layout
);
2247 Output_data_got
<64, false>* got
= target
->got_tlsdesc_section();
2248 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(reloc
.get_r_info());
2249 if (!object
->local_has_got_offset(r_sym
, GOT_TYPE_TLS_DESC
))
2251 unsigned int got_offset
= got
->add_constant(0);
2252 got
->add_constant(0);
2253 object
->set_local_got_offset(r_sym
, GOT_TYPE_TLS_DESC
,
2255 Reloc_section
* rt
= target
->rela_tlsdesc_section(layout
);
2256 // We store the arguments we need in a vector, and
2257 // use the index into the vector as the parameter
2258 // to pass to the target specific routines.
2259 uintptr_t intarg
= target
->add_tlsdesc_info(object
, r_sym
);
2260 void* arg
= reinterpret_cast<void*>(intarg
);
2261 rt
->add_target_specific(elfcpp::R_X86_64_TLSDESC
, arg
,
2262 got
, got_offset
, 0);
2265 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2266 unsupported_reloc_local(object
, r_type
);
2269 case elfcpp::R_X86_64_TLSDESC_CALL
:
2272 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
2273 if (optimized_type
== tls::TLSOPT_NONE
)
2275 // Create a GOT entry for the module index.
2276 target
->got_mod_index_entry(symtab
, layout
, object
);
2278 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2279 unsupported_reloc_local(object
, r_type
);
2282 case elfcpp::R_X86_64_DTPOFF32
:
2283 case elfcpp::R_X86_64_DTPOFF64
:
2286 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
2287 layout
->set_has_static_tls();
2288 if (optimized_type
== tls::TLSOPT_NONE
)
2290 // Create a GOT entry for the tp-relative offset.
2291 Output_data_got
<64, false>* got
2292 = target
->got_section(symtab
, layout
);
2293 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(reloc
.get_r_info());
2294 got
->add_local_with_rel(object
, r_sym
, GOT_TYPE_TLS_OFFSET
,
2295 target
->rela_dyn_section(layout
),
2296 elfcpp::R_X86_64_TPOFF64
);
2298 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2299 unsupported_reloc_local(object
, r_type
);
2302 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
2303 layout
->set_has_static_tls();
2304 if (output_is_shared
)
2305 unsupported_reloc_local(object
, r_type
);
2314 case elfcpp::R_X86_64_SIZE32
:
2315 case elfcpp::R_X86_64_SIZE64
:
2317 gold_error(_("%s: unsupported reloc %u against local symbol"),
2318 object
->name().c_str(), r_type
);
2324 // Report an unsupported relocation against a global symbol.
2328 Target_x86_64
<size
>::Scan::unsupported_reloc_global(
2329 Sized_relobj_file
<size
, false>* object
,
2330 unsigned int r_type
,
2333 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
2334 object
->name().c_str(), r_type
, gsym
->demangled_name().c_str());
2337 // Returns true if this relocation type could be that of a function pointer.
2340 Target_x86_64
<size
>::Scan::possible_function_pointer_reloc(unsigned int r_type
)
2344 case elfcpp::R_X86_64_64
:
2345 case elfcpp::R_X86_64_32
:
2346 case elfcpp::R_X86_64_32S
:
2347 case elfcpp::R_X86_64_16
:
2348 case elfcpp::R_X86_64_8
:
2349 case elfcpp::R_X86_64_GOT64
:
2350 case elfcpp::R_X86_64_GOT32
:
2351 case elfcpp::R_X86_64_GOTPCREL64
:
2352 case elfcpp::R_X86_64_GOTPCREL
:
2353 case elfcpp::R_X86_64_GOTPLT64
:
2361 // For safe ICF, scan a relocation for a local symbol to check if it
2362 // corresponds to a function pointer being taken. In that case mark
2363 // the function whose pointer was taken as not foldable.
2367 Target_x86_64
<size
>::Scan::local_reloc_may_be_function_pointer(
2370 Target_x86_64
<size
>* ,
2371 Sized_relobj_file
<size
, false>* ,
2374 const elfcpp::Rela
<size
, false>& ,
2375 unsigned int r_type
,
2376 const elfcpp::Sym
<size
, false>&)
2378 // When building a shared library, do not fold any local symbols as it is
2379 // not possible to distinguish pointer taken versus a call by looking at
2380 // the relocation types.
2381 return (parameters
->options().shared()
2382 || possible_function_pointer_reloc(r_type
));
2385 // For safe ICF, scan a relocation for a global symbol to check if it
2386 // corresponds to a function pointer being taken. In that case mark
2387 // the function whose pointer was taken as not foldable.
2391 Target_x86_64
<size
>::Scan::global_reloc_may_be_function_pointer(
2394 Target_x86_64
<size
>* ,
2395 Sized_relobj_file
<size
, false>* ,
2398 const elfcpp::Rela
<size
, false>& ,
2399 unsigned int r_type
,
2402 // When building a shared library, do not fold symbols whose visibility
2403 // is hidden, internal or protected.
2404 return ((parameters
->options().shared()
2405 && (gsym
->visibility() == elfcpp::STV_INTERNAL
2406 || gsym
->visibility() == elfcpp::STV_PROTECTED
2407 || gsym
->visibility() == elfcpp::STV_HIDDEN
))
2408 || possible_function_pointer_reloc(r_type
));
2411 // Scan a relocation for a global symbol.
2415 Target_x86_64
<size
>::Scan::global(Symbol_table
* symtab
,
2417 Target_x86_64
<size
>* target
,
2418 Sized_relobj_file
<size
, false>* object
,
2419 unsigned int data_shndx
,
2420 Output_section
* output_section
,
2421 const elfcpp::Rela
<size
, false>& reloc
,
2422 unsigned int r_type
,
2425 // A STT_GNU_IFUNC symbol may require a PLT entry.
2426 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
2427 && this->reloc_needs_plt_for_ifunc(object
, r_type
))
2428 target
->make_plt_entry(symtab
, layout
, gsym
);
2432 case elfcpp::R_X86_64_NONE
:
2433 case elfcpp::R_X86_64_GNU_VTINHERIT
:
2434 case elfcpp::R_X86_64_GNU_VTENTRY
:
2437 case elfcpp::R_X86_64_64
:
2438 case elfcpp::R_X86_64_32
:
2439 case elfcpp::R_X86_64_32S
:
2440 case elfcpp::R_X86_64_16
:
2441 case elfcpp::R_X86_64_8
:
2443 // Make a PLT entry if necessary.
2444 if (gsym
->needs_plt_entry())
2446 target
->make_plt_entry(symtab
, layout
, gsym
);
2447 // Since this is not a PC-relative relocation, we may be
2448 // taking the address of a function. In that case we need to
2449 // set the entry in the dynamic symbol table to the address of
2451 if (gsym
->is_from_dynobj() && !parameters
->options().shared())
2452 gsym
->set_needs_dynsym_value();
2454 // Make a dynamic relocation if necessary.
2455 if (gsym
->needs_dynamic_reloc(Scan::get_reference_flags(r_type
)))
2457 if (gsym
->may_need_copy_reloc())
2459 target
->copy_reloc(symtab
, layout
, object
,
2460 data_shndx
, output_section
, gsym
, reloc
);
2462 else if (r_type
== elfcpp::R_X86_64_64
2463 && gsym
->type() == elfcpp::STT_GNU_IFUNC
2464 && gsym
->can_use_relative_reloc(false)
2465 && !gsym
->is_from_dynobj()
2466 && !gsym
->is_undefined()
2467 && !gsym
->is_preemptible())
2469 // Use an IRELATIVE reloc for a locally defined
2470 // STT_GNU_IFUNC symbol. This makes a function
2471 // address in a PIE executable match the address in a
2472 // shared library that it links against.
2473 Reloc_section
* rela_dyn
=
2474 target
->rela_irelative_section(layout
);
2475 unsigned int r_type
= elfcpp::R_X86_64_IRELATIVE
;
2476 rela_dyn
->add_symbolless_global_addend(gsym
, r_type
,
2477 output_section
, object
,
2479 reloc
.get_r_offset(),
2480 reloc
.get_r_addend());
2482 else if (r_type
== elfcpp::R_X86_64_64
2483 && gsym
->can_use_relative_reloc(false))
2485 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
2486 rela_dyn
->add_global_relative(gsym
, elfcpp::R_X86_64_RELATIVE
,
2487 output_section
, object
,
2489 reloc
.get_r_offset(),
2490 reloc
.get_r_addend());
2494 this->check_non_pic(object
, r_type
, gsym
);
2495 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
2496 rela_dyn
->add_global(gsym
, r_type
, output_section
, object
,
2497 data_shndx
, reloc
.get_r_offset(),
2498 reloc
.get_r_addend());
2504 case elfcpp::R_X86_64_PC64
:
2505 case elfcpp::R_X86_64_PC32
:
2506 case elfcpp::R_X86_64_PC16
:
2507 case elfcpp::R_X86_64_PC8
:
2509 // Make a PLT entry if necessary.
2510 if (gsym
->needs_plt_entry())
2511 target
->make_plt_entry(symtab
, layout
, gsym
);
2512 // Make a dynamic relocation if necessary.
2513 if (gsym
->needs_dynamic_reloc(Scan::get_reference_flags(r_type
)))
2515 if (gsym
->may_need_copy_reloc())
2517 target
->copy_reloc(symtab
, layout
, object
,
2518 data_shndx
, output_section
, gsym
, reloc
);
2522 this->check_non_pic(object
, r_type
, gsym
);
2523 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
2524 rela_dyn
->add_global(gsym
, r_type
, output_section
, object
,
2525 data_shndx
, reloc
.get_r_offset(),
2526 reloc
.get_r_addend());
2532 case elfcpp::R_X86_64_GOT64
:
2533 case elfcpp::R_X86_64_GOT32
:
2534 case elfcpp::R_X86_64_GOTPCREL64
:
2535 case elfcpp::R_X86_64_GOTPCREL
:
2536 case elfcpp::R_X86_64_GOTPLT64
:
2538 // The symbol requires a GOT entry.
2539 Output_data_got
<64, false>* got
= target
->got_section(symtab
, layout
);
2540 if (gsym
->final_value_is_known())
2542 // For a STT_GNU_IFUNC symbol we want the PLT address.
2543 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
)
2544 got
->add_global_plt(gsym
, GOT_TYPE_STANDARD
);
2546 got
->add_global(gsym
, GOT_TYPE_STANDARD
);
2550 // If this symbol is not fully resolved, we need to add a
2551 // dynamic relocation for it.
2552 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
2554 // Use a GLOB_DAT rather than a RELATIVE reloc if:
2556 // 1) The symbol may be defined in some other module.
2558 // 2) We are building a shared library and this is a
2559 // protected symbol; using GLOB_DAT means that the dynamic
2560 // linker can use the address of the PLT in the main
2561 // executable when appropriate so that function address
2562 // comparisons work.
2564 // 3) This is a STT_GNU_IFUNC symbol in position dependent
2565 // code, again so that function address comparisons work.
2566 if (gsym
->is_from_dynobj()
2567 || gsym
->is_undefined()
2568 || gsym
->is_preemptible()
2569 || (gsym
->visibility() == elfcpp::STV_PROTECTED
2570 && parameters
->options().shared())
2571 || (gsym
->type() == elfcpp::STT_GNU_IFUNC
2572 && parameters
->options().output_is_position_independent()))
2573 got
->add_global_with_rel(gsym
, GOT_TYPE_STANDARD
, rela_dyn
,
2574 elfcpp::R_X86_64_GLOB_DAT
);
2577 // For a STT_GNU_IFUNC symbol we want to write the PLT
2578 // offset into the GOT, so that function pointer
2579 // comparisons work correctly.
2581 if (gsym
->type() != elfcpp::STT_GNU_IFUNC
)
2582 is_new
= got
->add_global(gsym
, GOT_TYPE_STANDARD
);
2585 is_new
= got
->add_global_plt(gsym
, GOT_TYPE_STANDARD
);
2586 // Tell the dynamic linker to use the PLT address
2587 // when resolving relocations.
2588 if (gsym
->is_from_dynobj()
2589 && !parameters
->options().shared())
2590 gsym
->set_needs_dynsym_value();
2594 unsigned int got_off
= gsym
->got_offset(GOT_TYPE_STANDARD
);
2595 rela_dyn
->add_global_relative(gsym
,
2596 elfcpp::R_X86_64_RELATIVE
,
2601 // For GOTPLT64, we also need a PLT entry (but only if the
2602 // symbol is not fully resolved).
2603 if (r_type
== elfcpp::R_X86_64_GOTPLT64
2604 && !gsym
->final_value_is_known())
2605 target
->make_plt_entry(symtab
, layout
, gsym
);
2609 case elfcpp::R_X86_64_PLT32
:
2610 // If the symbol is fully resolved, this is just a PC32 reloc.
2611 // Otherwise we need a PLT entry.
2612 if (gsym
->final_value_is_known())
2614 // If building a shared library, we can also skip the PLT entry
2615 // if the symbol is defined in the output file and is protected
2617 if (gsym
->is_defined()
2618 && !gsym
->is_from_dynobj()
2619 && !gsym
->is_preemptible())
2621 target
->make_plt_entry(symtab
, layout
, gsym
);
2624 case elfcpp::R_X86_64_GOTPC32
:
2625 case elfcpp::R_X86_64_GOTOFF64
:
2626 case elfcpp::R_X86_64_GOTPC64
:
2627 case elfcpp::R_X86_64_PLTOFF64
:
2628 // We need a GOT section.
2629 target
->got_section(symtab
, layout
);
2630 // For PLTOFF64, we also need a PLT entry (but only if the
2631 // symbol is not fully resolved).
2632 if (r_type
== elfcpp::R_X86_64_PLTOFF64
2633 && !gsym
->final_value_is_known())
2634 target
->make_plt_entry(symtab
, layout
, gsym
);
2637 case elfcpp::R_X86_64_COPY
:
2638 case elfcpp::R_X86_64_GLOB_DAT
:
2639 case elfcpp::R_X86_64_JUMP_SLOT
:
2640 case elfcpp::R_X86_64_RELATIVE
:
2641 case elfcpp::R_X86_64_IRELATIVE
:
2642 // These are outstanding tls relocs, which are unexpected when linking
2643 case elfcpp::R_X86_64_TPOFF64
:
2644 case elfcpp::R_X86_64_DTPMOD64
:
2645 case elfcpp::R_X86_64_TLSDESC
:
2646 gold_error(_("%s: unexpected reloc %u in object file"),
2647 object
->name().c_str(), r_type
);
2650 // These are initial tls relocs, which are expected for global()
2651 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
2652 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
2653 case elfcpp::R_X86_64_TLSDESC_CALL
:
2654 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
2655 case elfcpp::R_X86_64_DTPOFF32
:
2656 case elfcpp::R_X86_64_DTPOFF64
:
2657 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
2658 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
2660 const bool is_final
= gsym
->final_value_is_known();
2661 const tls::Tls_optimization optimized_type
2662 = Target_x86_64
<size
>::optimize_tls_reloc(is_final
, r_type
);
2665 case elfcpp::R_X86_64_TLSGD
: // General-dynamic
2666 if (optimized_type
== tls::TLSOPT_NONE
)
2668 // Create a pair of GOT entries for the module index and
2669 // dtv-relative offset.
2670 Output_data_got
<64, false>* got
2671 = target
->got_section(symtab
, layout
);
2672 got
->add_global_pair_with_rel(gsym
, GOT_TYPE_TLS_PAIR
,
2673 target
->rela_dyn_section(layout
),
2674 elfcpp::R_X86_64_DTPMOD64
,
2675 elfcpp::R_X86_64_DTPOFF64
);
2677 else if (optimized_type
== tls::TLSOPT_TO_IE
)
2679 // Create a GOT entry for the tp-relative offset.
2680 Output_data_got
<64, false>* got
2681 = target
->got_section(symtab
, layout
);
2682 got
->add_global_with_rel(gsym
, GOT_TYPE_TLS_OFFSET
,
2683 target
->rela_dyn_section(layout
),
2684 elfcpp::R_X86_64_TPOFF64
);
2686 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2687 unsupported_reloc_global(object
, r_type
, gsym
);
2690 case elfcpp::R_X86_64_GOTPC32_TLSDESC
:
2691 target
->define_tls_base_symbol(symtab
, layout
);
2692 if (optimized_type
== tls::TLSOPT_NONE
)
2694 // Create reserved PLT and GOT entries for the resolver.
2695 target
->reserve_tlsdesc_entries(symtab
, layout
);
2697 // Create a double GOT entry with an R_X86_64_TLSDESC
2698 // reloc. The R_X86_64_TLSDESC reloc is resolved
2699 // lazily, so the GOT entry needs to be in an area in
2700 // .got.plt, not .got. Call got_section to make sure
2701 // the section has been created.
2702 target
->got_section(symtab
, layout
);
2703 Output_data_got
<64, false>* got
= target
->got_tlsdesc_section();
2704 Reloc_section
* rt
= target
->rela_tlsdesc_section(layout
);
2705 got
->add_global_pair_with_rel(gsym
, GOT_TYPE_TLS_DESC
, rt
,
2706 elfcpp::R_X86_64_TLSDESC
, 0);
2708 else if (optimized_type
== tls::TLSOPT_TO_IE
)
2710 // Create a GOT entry for the tp-relative offset.
2711 Output_data_got
<64, false>* got
2712 = target
->got_section(symtab
, layout
);
2713 got
->add_global_with_rel(gsym
, GOT_TYPE_TLS_OFFSET
,
2714 target
->rela_dyn_section(layout
),
2715 elfcpp::R_X86_64_TPOFF64
);
2717 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2718 unsupported_reloc_global(object
, r_type
, gsym
);
2721 case elfcpp::R_X86_64_TLSDESC_CALL
:
2724 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
2725 if (optimized_type
== tls::TLSOPT_NONE
)
2727 // Create a GOT entry for the module index.
2728 target
->got_mod_index_entry(symtab
, layout
, object
);
2730 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2731 unsupported_reloc_global(object
, r_type
, gsym
);
2734 case elfcpp::R_X86_64_DTPOFF32
:
2735 case elfcpp::R_X86_64_DTPOFF64
:
2738 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
2739 layout
->set_has_static_tls();
2740 if (optimized_type
== tls::TLSOPT_NONE
)
2742 // Create a GOT entry for the tp-relative offset.
2743 Output_data_got
<64, false>* got
2744 = target
->got_section(symtab
, layout
);
2745 got
->add_global_with_rel(gsym
, GOT_TYPE_TLS_OFFSET
,
2746 target
->rela_dyn_section(layout
),
2747 elfcpp::R_X86_64_TPOFF64
);
2749 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2750 unsupported_reloc_global(object
, r_type
, gsym
);
2753 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
2754 layout
->set_has_static_tls();
2755 if (parameters
->options().shared())
2756 unsupported_reloc_local(object
, r_type
);
2765 case elfcpp::R_X86_64_SIZE32
:
2766 case elfcpp::R_X86_64_SIZE64
:
2768 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
2769 object
->name().c_str(), r_type
,
2770 gsym
->demangled_name().c_str());
2777 Target_x86_64
<size
>::gc_process_relocs(Symbol_table
* symtab
,
2779 Sized_relobj_file
<size
, false>* object
,
2780 unsigned int data_shndx
,
2781 unsigned int sh_type
,
2782 const unsigned char* prelocs
,
2784 Output_section
* output_section
,
2785 bool needs_special_offset_handling
,
2786 size_t local_symbol_count
,
2787 const unsigned char* plocal_symbols
)
2790 if (sh_type
== elfcpp::SHT_REL
)
2795 gold::gc_process_relocs
<size
, false, Target_x86_64
<size
>, elfcpp::SHT_RELA
,
2796 Target_x86_64
<size
>::Scan
,
2797 Target_x86_64
<size
>::Relocatable_size_for_reloc
>(
2806 needs_special_offset_handling
,
2811 // Scan relocations for a section.
2815 Target_x86_64
<size
>::scan_relocs(Symbol_table
* symtab
,
2817 Sized_relobj_file
<size
, false>* object
,
2818 unsigned int data_shndx
,
2819 unsigned int sh_type
,
2820 const unsigned char* prelocs
,
2822 Output_section
* output_section
,
2823 bool needs_special_offset_handling
,
2824 size_t local_symbol_count
,
2825 const unsigned char* plocal_symbols
)
2827 if (sh_type
== elfcpp::SHT_REL
)
2829 gold_error(_("%s: unsupported REL reloc section"),
2830 object
->name().c_str());
2834 gold::scan_relocs
<size
, false, Target_x86_64
<size
>, elfcpp::SHT_RELA
,
2835 Target_x86_64
<size
>::Scan
>(
2844 needs_special_offset_handling
,
2849 // Finalize the sections.
2853 Target_x86_64
<size
>::do_finalize_sections(
2855 const Input_objects
*,
2856 Symbol_table
* symtab
)
2858 const Reloc_section
* rel_plt
= (this->plt_
== NULL
2860 : this->plt_
->rela_plt());
2861 layout
->add_target_dynamic_tags(false, this->got_plt_
, rel_plt
,
2862 this->rela_dyn_
, true, false);
2864 // Fill in some more dynamic tags.
2865 Output_data_dynamic
* const odyn
= layout
->dynamic_data();
2868 if (this->plt_
!= NULL
2869 && this->plt_
->output_section() != NULL
2870 && this->plt_
->has_tlsdesc_entry())
2872 unsigned int plt_offset
= this->plt_
->get_tlsdesc_plt_offset();
2873 unsigned int got_offset
= this->plt_
->get_tlsdesc_got_offset();
2874 this->got_
->finalize_data_size();
2875 odyn
->add_section_plus_offset(elfcpp::DT_TLSDESC_PLT
,
2876 this->plt_
, plt_offset
);
2877 odyn
->add_section_plus_offset(elfcpp::DT_TLSDESC_GOT
,
2878 this->got_
, got_offset
);
2882 // Emit any relocs we saved in an attempt to avoid generating COPY
2884 if (this->copy_relocs_
.any_saved_relocs())
2885 this->copy_relocs_
.emit(this->rela_dyn_section(layout
));
2887 // Set the size of the _GLOBAL_OFFSET_TABLE_ symbol to the size of
2888 // the .got.plt section.
2889 Symbol
* sym
= this->global_offset_table_
;
2892 uint64_t data_size
= this->got_plt_
->current_data_size();
2893 symtab
->get_sized_symbol
<size
>(sym
)->set_symsize(data_size
);
2896 if (parameters
->doing_static_link()
2897 && (this->plt_
== NULL
|| !this->plt_
->has_irelative_section()))
2899 // If linking statically, make sure that the __rela_iplt symbols
2900 // were defined if necessary, even if we didn't create a PLT.
2901 static const Define_symbol_in_segment syms
[] =
2904 "__rela_iplt_start", // name
2905 elfcpp::PT_LOAD
, // segment_type
2906 elfcpp::PF_W
, // segment_flags_set
2907 elfcpp::PF(0), // segment_flags_clear
2910 elfcpp::STT_NOTYPE
, // type
2911 elfcpp::STB_GLOBAL
, // binding
2912 elfcpp::STV_HIDDEN
, // visibility
2914 Symbol::SEGMENT_START
, // offset_from_base
2918 "__rela_iplt_end", // name
2919 elfcpp::PT_LOAD
, // segment_type
2920 elfcpp::PF_W
, // segment_flags_set
2921 elfcpp::PF(0), // segment_flags_clear
2924 elfcpp::STT_NOTYPE
, // type
2925 elfcpp::STB_GLOBAL
, // binding
2926 elfcpp::STV_HIDDEN
, // visibility
2928 Symbol::SEGMENT_START
, // offset_from_base
2933 symtab
->define_symbols(layout
, 2, syms
,
2934 layout
->script_options()->saw_sections_clause());
2938 // Perform a relocation.
2942 Target_x86_64
<size
>::Relocate::relocate(
2943 const Relocate_info
<size
, false>* relinfo
,
2944 Target_x86_64
<size
>* target
,
2947 const elfcpp::Rela
<size
, false>& rela
,
2948 unsigned int r_type
,
2949 const Sized_symbol
<size
>* gsym
,
2950 const Symbol_value
<size
>* psymval
,
2951 unsigned char* view
,
2952 typename
elfcpp::Elf_types
<size
>::Elf_Addr address
,
2953 section_size_type view_size
)
2955 if (this->skip_call_tls_get_addr_
)
2957 if ((r_type
!= elfcpp::R_X86_64_PLT32
2958 && r_type
!= elfcpp::R_X86_64_PC32
)
2960 || strcmp(gsym
->name(), "__tls_get_addr") != 0)
2962 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
2963 _("missing expected TLS relocation"));
2967 this->skip_call_tls_get_addr_
= false;
2972 const Sized_relobj_file
<size
, false>* object
= relinfo
->object
;
2974 // Pick the value to use for symbols defined in the PLT.
2975 Symbol_value
<size
> symval
;
2977 && gsym
->use_plt_offset(Scan::get_reference_flags(r_type
)))
2979 symval
.set_output_value(target
->plt_address_for_global(gsym
)
2980 + gsym
->plt_offset());
2983 else if (gsym
== NULL
&& psymval
->is_ifunc_symbol())
2985 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(rela
.get_r_info());
2986 if (object
->local_has_plt_offset(r_sym
))
2988 symval
.set_output_value(target
->plt_address_for_local(object
, r_sym
)
2989 + object
->local_plt_offset(r_sym
));
2994 const elfcpp::Elf_Xword addend
= rela
.get_r_addend();
2996 // Get the GOT offset if needed.
2997 // The GOT pointer points to the end of the GOT section.
2998 // We need to subtract the size of the GOT section to get
2999 // the actual offset to use in the relocation.
3000 bool have_got_offset
= false;
3001 unsigned int got_offset
= 0;
3004 case elfcpp::R_X86_64_GOT32
:
3005 case elfcpp::R_X86_64_GOT64
:
3006 case elfcpp::R_X86_64_GOTPLT64
:
3007 case elfcpp::R_X86_64_GOTPCREL
:
3008 case elfcpp::R_X86_64_GOTPCREL64
:
3011 gold_assert(gsym
->has_got_offset(GOT_TYPE_STANDARD
));
3012 got_offset
= gsym
->got_offset(GOT_TYPE_STANDARD
) - target
->got_size();
3016 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(rela
.get_r_info());
3017 gold_assert(object
->local_has_got_offset(r_sym
, GOT_TYPE_STANDARD
));
3018 got_offset
= (object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
)
3019 - target
->got_size());
3021 have_got_offset
= true;
3030 case elfcpp::R_X86_64_NONE
:
3031 case elfcpp::R_X86_64_GNU_VTINHERIT
:
3032 case elfcpp::R_X86_64_GNU_VTENTRY
:
3035 case elfcpp::R_X86_64_64
:
3036 Relocate_functions
<size
, false>::rela64(view
, object
, psymval
, addend
);
3039 case elfcpp::R_X86_64_PC64
:
3040 Relocate_functions
<size
, false>::pcrela64(view
, object
, psymval
, addend
,
3044 case elfcpp::R_X86_64_32
:
3045 // FIXME: we need to verify that value + addend fits into 32 bits:
3046 // uint64_t x = value + addend;
3047 // x == static_cast<uint64_t>(static_cast<uint32_t>(x))
3048 // Likewise for other <=32-bit relocations (but see R_X86_64_32S).
3049 Relocate_functions
<size
, false>::rela32(view
, object
, psymval
, addend
);
3052 case elfcpp::R_X86_64_32S
:
3053 // FIXME: we need to verify that value + addend fits into 32 bits:
3054 // int64_t x = value + addend; // note this quantity is signed!
3055 // x == static_cast<int64_t>(static_cast<int32_t>(x))
3056 Relocate_functions
<size
, false>::rela32(view
, object
, psymval
, addend
);
3059 case elfcpp::R_X86_64_PC32
:
3060 Relocate_functions
<size
, false>::pcrela32(view
, object
, psymval
, addend
,
3064 case elfcpp::R_X86_64_16
:
3065 Relocate_functions
<size
, false>::rela16(view
, object
, psymval
, addend
);
3068 case elfcpp::R_X86_64_PC16
:
3069 Relocate_functions
<size
, false>::pcrela16(view
, object
, psymval
, addend
,
3073 case elfcpp::R_X86_64_8
:
3074 Relocate_functions
<size
, false>::rela8(view
, object
, psymval
, addend
);
3077 case elfcpp::R_X86_64_PC8
:
3078 Relocate_functions
<size
, false>::pcrela8(view
, object
, psymval
, addend
,
3082 case elfcpp::R_X86_64_PLT32
:
3083 gold_assert(gsym
== NULL
3084 || gsym
->has_plt_offset()
3085 || gsym
->final_value_is_known()
3086 || (gsym
->is_defined()
3087 && !gsym
->is_from_dynobj()
3088 && !gsym
->is_preemptible()));
3089 // Note: while this code looks the same as for R_X86_64_PC32, it
3090 // behaves differently because psymval was set to point to
3091 // the PLT entry, rather than the symbol, in Scan::global().
3092 Relocate_functions
<size
, false>::pcrela32(view
, object
, psymval
, addend
,
3096 case elfcpp::R_X86_64_PLTOFF64
:
3099 gold_assert(gsym
->has_plt_offset()
3100 || gsym
->final_value_is_known());
3101 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
;
3102 got_address
= target
->got_section(NULL
, NULL
)->address();
3103 Relocate_functions
<size
, false>::rela64(view
, object
, psymval
,
3104 addend
- got_address
);
3107 case elfcpp::R_X86_64_GOT32
:
3108 gold_assert(have_got_offset
);
3109 Relocate_functions
<size
, false>::rela32(view
, got_offset
, addend
);
3112 case elfcpp::R_X86_64_GOTPC32
:
3115 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
;
3116 value
= target
->got_plt_section()->address();
3117 Relocate_functions
<size
, false>::pcrela32(view
, value
, addend
, address
);
3121 case elfcpp::R_X86_64_GOT64
:
3122 // The ABI doc says "Like GOT64, but indicates a PLT entry is needed."
3123 // Since we always add a PLT entry, this is equivalent.
3124 case elfcpp::R_X86_64_GOTPLT64
:
3125 gold_assert(have_got_offset
);
3126 Relocate_functions
<size
, false>::rela64(view
, got_offset
, addend
);
3129 case elfcpp::R_X86_64_GOTPC64
:
3132 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
;
3133 value
= target
->got_plt_section()->address();
3134 Relocate_functions
<size
, false>::pcrela64(view
, value
, addend
, address
);
3138 case elfcpp::R_X86_64_GOTOFF64
:
3140 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
;
3141 value
= (psymval
->value(object
, 0)
3142 - target
->got_plt_section()->address());
3143 Relocate_functions
<size
, false>::rela64(view
, value
, addend
);
3147 case elfcpp::R_X86_64_GOTPCREL
:
3149 gold_assert(have_got_offset
);
3150 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
;
3151 value
= target
->got_plt_section()->address() + got_offset
;
3152 Relocate_functions
<size
, false>::pcrela32(view
, value
, addend
, address
);
3156 case elfcpp::R_X86_64_GOTPCREL64
:
3158 gold_assert(have_got_offset
);
3159 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
;
3160 value
= target
->got_plt_section()->address() + got_offset
;
3161 Relocate_functions
<size
, false>::pcrela64(view
, value
, addend
, address
);
3165 case elfcpp::R_X86_64_COPY
:
3166 case elfcpp::R_X86_64_GLOB_DAT
:
3167 case elfcpp::R_X86_64_JUMP_SLOT
:
3168 case elfcpp::R_X86_64_RELATIVE
:
3169 case elfcpp::R_X86_64_IRELATIVE
:
3170 // These are outstanding tls relocs, which are unexpected when linking
3171 case elfcpp::R_X86_64_TPOFF64
:
3172 case elfcpp::R_X86_64_DTPMOD64
:
3173 case elfcpp::R_X86_64_TLSDESC
:
3174 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
3175 _("unexpected reloc %u in object file"),
3179 // These are initial tls relocs, which are expected when linking
3180 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
3181 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
3182 case elfcpp::R_X86_64_TLSDESC_CALL
:
3183 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
3184 case elfcpp::R_X86_64_DTPOFF32
:
3185 case elfcpp::R_X86_64_DTPOFF64
:
3186 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
3187 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
3188 this->relocate_tls(relinfo
, target
, relnum
, rela
, r_type
, gsym
, psymval
,
3189 view
, address
, view_size
);
3192 case elfcpp::R_X86_64_SIZE32
:
3193 case elfcpp::R_X86_64_SIZE64
:
3195 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
3196 _("unsupported reloc %u"),
3204 // Perform a TLS relocation.
3208 Target_x86_64
<size
>::Relocate::relocate_tls(
3209 const Relocate_info
<size
, false>* relinfo
,
3210 Target_x86_64
<size
>* target
,
3212 const elfcpp::Rela
<size
, false>& rela
,
3213 unsigned int r_type
,
3214 const Sized_symbol
<size
>* gsym
,
3215 const Symbol_value
<size
>* psymval
,
3216 unsigned char* view
,
3217 typename
elfcpp::Elf_types
<size
>::Elf_Addr address
,
3218 section_size_type view_size
)
3220 Output_segment
* tls_segment
= relinfo
->layout
->tls_segment();
3222 const Sized_relobj_file
<size
, false>* object
= relinfo
->object
;
3223 const elfcpp::Elf_Xword addend
= rela
.get_r_addend();
3224 elfcpp::Shdr
<size
, false> data_shdr(relinfo
->data_shdr
);
3225 bool is_executable
= (data_shdr
.get_sh_flags() & elfcpp::SHF_EXECINSTR
) != 0;
3227 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
= psymval
->value(relinfo
->object
, 0);
3229 const bool is_final
= (gsym
== NULL
3230 ? !parameters
->options().shared()
3231 : gsym
->final_value_is_known());
3232 tls::Tls_optimization optimized_type
3233 = Target_x86_64
<size
>::optimize_tls_reloc(is_final
, r_type
);
3236 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
3237 if (!is_executable
&& optimized_type
== tls::TLSOPT_TO_LE
)
3239 // If this code sequence is used in a non-executable section,
3240 // we will not optimize the R_X86_64_DTPOFF32/64 relocation,
3241 // on the assumption that it's being used by itself in a debug
3242 // section. Therefore, in the unlikely event that the code
3243 // sequence appears in a non-executable section, we simply
3244 // leave it unoptimized.
3245 optimized_type
= tls::TLSOPT_NONE
;
3247 if (optimized_type
== tls::TLSOPT_TO_LE
)
3249 if (tls_segment
== NULL
)
3251 gold_assert(parameters
->errors()->error_count() > 0
3252 || issue_undefined_symbol_error(gsym
));
3255 this->tls_gd_to_le(relinfo
, relnum
, tls_segment
,
3256 rela
, r_type
, value
, view
,
3262 unsigned int got_type
= (optimized_type
== tls::TLSOPT_TO_IE
3263 ? GOT_TYPE_TLS_OFFSET
3264 : GOT_TYPE_TLS_PAIR
);
3265 unsigned int got_offset
;
3268 gold_assert(gsym
->has_got_offset(got_type
));
3269 got_offset
= gsym
->got_offset(got_type
) - target
->got_size();
3273 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(rela
.get_r_info());
3274 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
3275 got_offset
= (object
->local_got_offset(r_sym
, got_type
)
3276 - target
->got_size());
3278 if (optimized_type
== tls::TLSOPT_TO_IE
)
3280 value
= target
->got_plt_section()->address() + got_offset
;
3281 this->tls_gd_to_ie(relinfo
, relnum
, tls_segment
, rela
, r_type
,
3282 value
, view
, address
, view_size
);
3285 else if (optimized_type
== tls::TLSOPT_NONE
)
3287 // Relocate the field with the offset of the pair of GOT
3289 value
= target
->got_plt_section()->address() + got_offset
;
3290 Relocate_functions
<size
, false>::pcrela32(view
, value
, addend
,
3295 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
3296 _("unsupported reloc %u"), r_type
);
3299 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
3300 case elfcpp::R_X86_64_TLSDESC_CALL
:
3301 if (!is_executable
&& optimized_type
== tls::TLSOPT_TO_LE
)
3303 // See above comment for R_X86_64_TLSGD.
3304 optimized_type
= tls::TLSOPT_NONE
;
3306 if (optimized_type
== tls::TLSOPT_TO_LE
)
3308 if (tls_segment
== NULL
)
3310 gold_assert(parameters
->errors()->error_count() > 0
3311 || issue_undefined_symbol_error(gsym
));
3314 this->tls_desc_gd_to_le(relinfo
, relnum
, tls_segment
,
3315 rela
, r_type
, value
, view
,
3321 unsigned int got_type
= (optimized_type
== tls::TLSOPT_TO_IE
3322 ? GOT_TYPE_TLS_OFFSET
3323 : GOT_TYPE_TLS_DESC
);
3324 unsigned int got_offset
= 0;
3325 if (r_type
== elfcpp::R_X86_64_GOTPC32_TLSDESC
3326 && optimized_type
== tls::TLSOPT_NONE
)
3328 // We created GOT entries in the .got.tlsdesc portion of
3329 // the .got.plt section, but the offset stored in the
3330 // symbol is the offset within .got.tlsdesc.
3331 got_offset
= (target
->got_size()
3332 + target
->got_plt_section()->data_size());
3336 gold_assert(gsym
->has_got_offset(got_type
));
3337 got_offset
+= gsym
->got_offset(got_type
) - target
->got_size();
3341 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(rela
.get_r_info());
3342 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
3343 got_offset
+= (object
->local_got_offset(r_sym
, got_type
)
3344 - target
->got_size());
3346 if (optimized_type
== tls::TLSOPT_TO_IE
)
3348 if (tls_segment
== NULL
)
3350 gold_assert(parameters
->errors()->error_count() > 0
3351 || issue_undefined_symbol_error(gsym
));
3354 value
= target
->got_plt_section()->address() + got_offset
;
3355 this->tls_desc_gd_to_ie(relinfo
, relnum
, tls_segment
,
3356 rela
, r_type
, value
, view
, address
,
3360 else if (optimized_type
== tls::TLSOPT_NONE
)
3362 if (r_type
== elfcpp::R_X86_64_GOTPC32_TLSDESC
)
3364 // Relocate the field with the offset of the pair of GOT
3366 value
= target
->got_plt_section()->address() + got_offset
;
3367 Relocate_functions
<size
, false>::pcrela32(view
, value
, addend
,
3373 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
3374 _("unsupported reloc %u"), r_type
);
3377 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
3378 if (!is_executable
&& optimized_type
== tls::TLSOPT_TO_LE
)
3380 // See above comment for R_X86_64_TLSGD.
3381 optimized_type
= tls::TLSOPT_NONE
;
3383 if (optimized_type
== tls::TLSOPT_TO_LE
)
3385 if (tls_segment
== NULL
)
3387 gold_assert(parameters
->errors()->error_count() > 0
3388 || issue_undefined_symbol_error(gsym
));
3391 this->tls_ld_to_le(relinfo
, relnum
, tls_segment
, rela
, r_type
,
3392 value
, view
, view_size
);
3395 else if (optimized_type
== tls::TLSOPT_NONE
)
3397 // Relocate the field with the offset of the GOT entry for
3398 // the module index.
3399 unsigned int got_offset
;
3400 got_offset
= (target
->got_mod_index_entry(NULL
, NULL
, NULL
)
3401 - target
->got_size());
3402 value
= target
->got_plt_section()->address() + got_offset
;
3403 Relocate_functions
<size
, false>::pcrela32(view
, value
, addend
,
3407 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
3408 _("unsupported reloc %u"), r_type
);
3411 case elfcpp::R_X86_64_DTPOFF32
:
3412 // This relocation type is used in debugging information.
3413 // In that case we need to not optimize the value. If the
3414 // section is not executable, then we assume we should not
3415 // optimize this reloc. See comments above for R_X86_64_TLSGD,
3416 // R_X86_64_GOTPC32_TLSDESC, R_X86_64_TLSDESC_CALL, and
3418 if (optimized_type
== tls::TLSOPT_TO_LE
&& is_executable
)
3420 if (tls_segment
== NULL
)
3422 gold_assert(parameters
->errors()->error_count() > 0
3423 || issue_undefined_symbol_error(gsym
));
3426 value
-= tls_segment
->memsz();
3428 Relocate_functions
<size
, false>::rela32(view
, value
, addend
);
3431 case elfcpp::R_X86_64_DTPOFF64
:
3432 // See R_X86_64_DTPOFF32, just above, for why we check for is_executable.
3433 if (optimized_type
== tls::TLSOPT_TO_LE
&& is_executable
)
3435 if (tls_segment
== NULL
)
3437 gold_assert(parameters
->errors()->error_count() > 0
3438 || issue_undefined_symbol_error(gsym
));
3441 value
-= tls_segment
->memsz();
3443 Relocate_functions
<size
, false>::rela64(view
, value
, addend
);
3446 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
3447 if (optimized_type
== tls::TLSOPT_TO_LE
)
3449 if (tls_segment
== NULL
)
3451 gold_assert(parameters
->errors()->error_count() > 0
3452 || issue_undefined_symbol_error(gsym
));
3455 Target_x86_64
<size
>::Relocate::tls_ie_to_le(relinfo
, relnum
,
3457 r_type
, value
, view
,
3461 else if (optimized_type
== tls::TLSOPT_NONE
)
3463 // Relocate the field with the offset of the GOT entry for
3464 // the tp-relative offset of the symbol.
3465 unsigned int got_offset
;
3468 gold_assert(gsym
->has_got_offset(GOT_TYPE_TLS_OFFSET
));
3469 got_offset
= (gsym
->got_offset(GOT_TYPE_TLS_OFFSET
)
3470 - target
->got_size());
3474 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(rela
.get_r_info());
3475 gold_assert(object
->local_has_got_offset(r_sym
,
3476 GOT_TYPE_TLS_OFFSET
));
3477 got_offset
= (object
->local_got_offset(r_sym
, GOT_TYPE_TLS_OFFSET
)
3478 - target
->got_size());
3480 value
= target
->got_plt_section()->address() + got_offset
;
3481 Relocate_functions
<size
, false>::pcrela32(view
, value
, addend
,
3485 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
3486 _("unsupported reloc type %u"),
3490 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
3491 if (tls_segment
== NULL
)
3493 gold_assert(parameters
->errors()->error_count() > 0
3494 || issue_undefined_symbol_error(gsym
));
3497 value
-= tls_segment
->memsz();
3498 Relocate_functions
<size
, false>::rela32(view
, value
, addend
);
3503 // Do a relocation in which we convert a TLS General-Dynamic to an
3508 Target_x86_64
<size
>::Relocate::tls_gd_to_ie(
3509 const Relocate_info
<size
, false>* relinfo
,
3512 const elfcpp::Rela
<size
, false>& rela
,
3514 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
3515 unsigned char* view
,
3516 typename
elfcpp::Elf_types
<size
>::Elf_Addr address
,
3517 section_size_type view_size
)
3519 // .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
3520 // .word 0x6666; rex64; call __tls_get_addr
3521 // ==> movq %fs:0,%rax; addq x@gottpoff(%rip),%rax
3523 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -4);
3524 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 12);
3526 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
3527 (memcmp(view
- 4, "\x66\x48\x8d\x3d", 4) == 0));
3528 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
3529 (memcmp(view
+ 4, "\x66\x66\x48\xe8", 4) == 0));
3531 memcpy(view
- 4, "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x03\x05\0\0\0\0", 16);
3533 const elfcpp::Elf_Xword addend
= rela
.get_r_addend();
3534 Relocate_functions
<size
, false>::pcrela32(view
+ 8, value
, addend
- 8,
3537 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3539 this->skip_call_tls_get_addr_
= true;
3542 // Do a relocation in which we convert a TLS General-Dynamic to a
3547 Target_x86_64
<size
>::Relocate::tls_gd_to_le(
3548 const Relocate_info
<size
, false>* relinfo
,
3550 Output_segment
* tls_segment
,
3551 const elfcpp::Rela
<size
, false>& rela
,
3553 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
3554 unsigned char* view
,
3555 section_size_type view_size
)
3557 // .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
3558 // .word 0x6666; rex64; call __tls_get_addr
3559 // ==> movq %fs:0,%rax; leaq x@tpoff(%rax),%rax
3561 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -4);
3562 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 12);
3564 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
3565 (memcmp(view
- 4, "\x66\x48\x8d\x3d", 4) == 0));
3566 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
3567 (memcmp(view
+ 4, "\x66\x66\x48\xe8", 4) == 0));
3569 memcpy(view
- 4, "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0\0", 16);
3571 value
-= tls_segment
->memsz();
3572 Relocate_functions
<size
, false>::rela32(view
+ 8, value
, 0);
3574 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3576 this->skip_call_tls_get_addr_
= true;
3579 // Do a TLSDESC-style General-Dynamic to Initial-Exec transition.
3583 Target_x86_64
<size
>::Relocate::tls_desc_gd_to_ie(
3584 const Relocate_info
<size
, false>* relinfo
,
3587 const elfcpp::Rela
<size
, false>& rela
,
3588 unsigned int r_type
,
3589 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
3590 unsigned char* view
,
3591 typename
elfcpp::Elf_types
<size
>::Elf_Addr address
,
3592 section_size_type view_size
)
3594 if (r_type
== elfcpp::R_X86_64_GOTPC32_TLSDESC
)
3596 // leaq foo@tlsdesc(%rip), %rax
3597 // ==> movq foo@gottpoff(%rip), %rax
3598 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -3);
3599 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 4);
3600 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
3601 view
[-3] == 0x48 && view
[-2] == 0x8d && view
[-1] == 0x05);
3603 const elfcpp::Elf_Xword addend
= rela
.get_r_addend();
3604 Relocate_functions
<size
, false>::pcrela32(view
, value
, addend
, address
);
3608 // call *foo@tlscall(%rax)
3610 gold_assert(r_type
== elfcpp::R_X86_64_TLSDESC_CALL
);
3611 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 2);
3612 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
3613 view
[0] == 0xff && view
[1] == 0x10);
3619 // Do a TLSDESC-style General-Dynamic to Local-Exec transition.
3623 Target_x86_64
<size
>::Relocate::tls_desc_gd_to_le(
3624 const Relocate_info
<size
, false>* relinfo
,
3626 Output_segment
* tls_segment
,
3627 const elfcpp::Rela
<size
, false>& rela
,
3628 unsigned int r_type
,
3629 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
3630 unsigned char* view
,
3631 section_size_type view_size
)
3633 if (r_type
== elfcpp::R_X86_64_GOTPC32_TLSDESC
)
3635 // leaq foo@tlsdesc(%rip), %rax
3636 // ==> movq foo@tpoff, %rax
3637 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -3);
3638 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 4);
3639 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
3640 view
[-3] == 0x48 && view
[-2] == 0x8d && view
[-1] == 0x05);
3643 value
-= tls_segment
->memsz();
3644 Relocate_functions
<size
, false>::rela32(view
, value
, 0);
3648 // call *foo@tlscall(%rax)
3650 gold_assert(r_type
== elfcpp::R_X86_64_TLSDESC_CALL
);
3651 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 2);
3652 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
3653 view
[0] == 0xff && view
[1] == 0x10);
3661 Target_x86_64
<size
>::Relocate::tls_ld_to_le(
3662 const Relocate_info
<size
, false>* relinfo
,
3665 const elfcpp::Rela
<size
, false>& rela
,
3667 typename
elfcpp::Elf_types
<size
>::Elf_Addr
,
3668 unsigned char* view
,
3669 section_size_type view_size
)
3671 // leaq foo@tlsld(%rip),%rdi; call __tls_get_addr@plt;
3672 // ... leq foo@dtpoff(%rax),%reg
3673 // ==> .word 0x6666; .byte 0x66; movq %fs:0,%rax ... leaq x@tpoff(%rax),%rdx
3675 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -3);
3676 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 9);
3678 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
3679 view
[-3] == 0x48 && view
[-2] == 0x8d && view
[-1] == 0x3d);
3681 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(), view
[4] == 0xe8);
3683 memcpy(view
- 3, "\x66\x66\x66\x64\x48\x8b\x04\x25\0\0\0\0", 12);
3685 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3687 this->skip_call_tls_get_addr_
= true;
3690 // Do a relocation in which we convert a TLS Initial-Exec to a
3695 Target_x86_64
<size
>::Relocate::tls_ie_to_le(
3696 const Relocate_info
<size
, false>* relinfo
,
3698 Output_segment
* tls_segment
,
3699 const elfcpp::Rela
<size
, false>& rela
,
3701 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
3702 unsigned char* view
,
3703 section_size_type view_size
)
3705 // We need to examine the opcodes to figure out which instruction we
3708 // movq foo@gottpoff(%rip),%reg ==> movq $YY,%reg
3709 // addq foo@gottpoff(%rip),%reg ==> addq $YY,%reg
3711 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -3);
3712 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 4);
3714 unsigned char op1
= view
[-3];
3715 unsigned char op2
= view
[-2];
3716 unsigned char op3
= view
[-1];
3717 unsigned char reg
= op3
>> 3;
3725 view
[-1] = 0xc0 | reg
;
3729 // Special handling for %rsp.
3733 view
[-1] = 0xc0 | reg
;
3741 view
[-1] = 0x80 | reg
| (reg
<< 3);
3744 value
-= tls_segment
->memsz();
3745 Relocate_functions
<size
, false>::rela32(view
, value
, 0);
3748 // Relocate section data.
3752 Target_x86_64
<size
>::relocate_section(
3753 const Relocate_info
<size
, false>* relinfo
,
3754 unsigned int sh_type
,
3755 const unsigned char* prelocs
,
3757 Output_section
* output_section
,
3758 bool needs_special_offset_handling
,
3759 unsigned char* view
,
3760 typename
elfcpp::Elf_types
<size
>::Elf_Addr address
,
3761 section_size_type view_size
,
3762 const Reloc_symbol_changes
* reloc_symbol_changes
)
3764 gold_assert(sh_type
== elfcpp::SHT_RELA
);
3766 gold::relocate_section
<size
, false, Target_x86_64
<size
>, elfcpp::SHT_RELA
,
3767 Target_x86_64
<size
>::Relocate
>(
3773 needs_special_offset_handling
,
3777 reloc_symbol_changes
);
3780 // Apply an incremental relocation. Incremental relocations always refer
3781 // to global symbols.
3785 Target_x86_64
<size
>::apply_relocation(
3786 const Relocate_info
<size
, false>* relinfo
,
3787 typename
elfcpp::Elf_types
<size
>::Elf_Addr r_offset
,
3788 unsigned int r_type
,
3789 typename
elfcpp::Elf_types
<size
>::Elf_Swxword r_addend
,
3791 unsigned char* view
,
3792 typename
elfcpp::Elf_types
<size
>::Elf_Addr address
,
3793 section_size_type view_size
)
3795 gold::apply_relocation
<size
, false, Target_x86_64
<size
>,
3796 Target_x86_64
<size
>::Relocate
>(
3808 // Return the size of a relocation while scanning during a relocatable
3813 Target_x86_64
<size
>::Relocatable_size_for_reloc::get_size_for_reloc(
3814 unsigned int r_type
,
3819 case elfcpp::R_X86_64_NONE
:
3820 case elfcpp::R_X86_64_GNU_VTINHERIT
:
3821 case elfcpp::R_X86_64_GNU_VTENTRY
:
3822 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
3823 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
3824 case elfcpp::R_X86_64_TLSDESC_CALL
:
3825 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
3826 case elfcpp::R_X86_64_DTPOFF32
:
3827 case elfcpp::R_X86_64_DTPOFF64
:
3828 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
3829 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
3832 case elfcpp::R_X86_64_64
:
3833 case elfcpp::R_X86_64_PC64
:
3834 case elfcpp::R_X86_64_GOTOFF64
:
3835 case elfcpp::R_X86_64_GOTPC64
:
3836 case elfcpp::R_X86_64_PLTOFF64
:
3837 case elfcpp::R_X86_64_GOT64
:
3838 case elfcpp::R_X86_64_GOTPCREL64
:
3839 case elfcpp::R_X86_64_GOTPCREL
:
3840 case elfcpp::R_X86_64_GOTPLT64
:
3843 case elfcpp::R_X86_64_32
:
3844 case elfcpp::R_X86_64_32S
:
3845 case elfcpp::R_X86_64_PC32
:
3846 case elfcpp::R_X86_64_PLT32
:
3847 case elfcpp::R_X86_64_GOTPC32
:
3848 case elfcpp::R_X86_64_GOT32
:
3851 case elfcpp::R_X86_64_16
:
3852 case elfcpp::R_X86_64_PC16
:
3855 case elfcpp::R_X86_64_8
:
3856 case elfcpp::R_X86_64_PC8
:
3859 case elfcpp::R_X86_64_COPY
:
3860 case elfcpp::R_X86_64_GLOB_DAT
:
3861 case elfcpp::R_X86_64_JUMP_SLOT
:
3862 case elfcpp::R_X86_64_RELATIVE
:
3863 case elfcpp::R_X86_64_IRELATIVE
:
3864 // These are outstanding tls relocs, which are unexpected when linking
3865 case elfcpp::R_X86_64_TPOFF64
:
3866 case elfcpp::R_X86_64_DTPMOD64
:
3867 case elfcpp::R_X86_64_TLSDESC
:
3868 object
->error(_("unexpected reloc %u in object file"), r_type
);
3871 case elfcpp::R_X86_64_SIZE32
:
3872 case elfcpp::R_X86_64_SIZE64
:
3874 object
->error(_("unsupported reloc %u against local symbol"), r_type
);
3879 // Scan the relocs during a relocatable link.
3883 Target_x86_64
<size
>::scan_relocatable_relocs(
3884 Symbol_table
* symtab
,
3886 Sized_relobj_file
<size
, false>* object
,
3887 unsigned int data_shndx
,
3888 unsigned int sh_type
,
3889 const unsigned char* prelocs
,
3891 Output_section
* output_section
,
3892 bool needs_special_offset_handling
,
3893 size_t local_symbol_count
,
3894 const unsigned char* plocal_symbols
,
3895 Relocatable_relocs
* rr
)
3897 gold_assert(sh_type
== elfcpp::SHT_RELA
);
3899 typedef gold::Default_scan_relocatable_relocs
<elfcpp::SHT_RELA
,
3900 Relocatable_size_for_reloc
> Scan_relocatable_relocs
;
3902 gold::scan_relocatable_relocs
<size
, false, elfcpp::SHT_RELA
,
3903 Scan_relocatable_relocs
>(
3911 needs_special_offset_handling
,
3917 // Relocate a section during a relocatable link.
3921 Target_x86_64
<size
>::relocate_for_relocatable(
3922 const Relocate_info
<size
, false>* relinfo
,
3923 unsigned int sh_type
,
3924 const unsigned char* prelocs
,
3926 Output_section
* output_section
,
3927 off_t offset_in_output_section
,
3928 const Relocatable_relocs
* rr
,
3929 unsigned char* view
,
3930 typename
elfcpp::Elf_types
<size
>::Elf_Addr view_address
,
3931 section_size_type view_size
,
3932 unsigned char* reloc_view
,
3933 section_size_type reloc_view_size
)
3935 gold_assert(sh_type
== elfcpp::SHT_RELA
);
3937 gold::relocate_for_relocatable
<size
, false, elfcpp::SHT_RELA
>(
3942 offset_in_output_section
,
3951 // Return the value to use for a dynamic which requires special
3952 // treatment. This is how we support equality comparisons of function
3953 // pointers across shared library boundaries, as described in the
3954 // processor specific ABI supplement.
3958 Target_x86_64
<size
>::do_dynsym_value(const Symbol
* gsym
) const
3960 gold_assert(gsym
->is_from_dynobj() && gsym
->has_plt_offset());
3961 return this->plt_address_for_global(gsym
) + gsym
->plt_offset();
3964 // Return a string used to fill a code section with nops to take up
3965 // the specified length.
3969 Target_x86_64
<size
>::do_code_fill(section_size_type length
) const
3973 // Build a jmpq instruction to skip over the bytes.
3974 unsigned char jmp
[5];
3976 elfcpp::Swap_unaligned
<32, false>::writeval(jmp
+ 1, length
- 5);
3977 return (std::string(reinterpret_cast<char*>(&jmp
[0]), 5)
3978 + std::string(length
- 5, '\0'));
3981 // Nop sequences of various lengths.
3982 const char nop1
[1] = { '\x90' }; // nop
3983 const char nop2
[2] = { '\x66', '\x90' }; // xchg %ax %ax
3984 const char nop3
[3] = { '\x0f', '\x1f', '\x00' }; // nop (%rax)
3985 const char nop4
[4] = { '\x0f', '\x1f', '\x40', // nop 0(%rax)
3987 const char nop5
[5] = { '\x0f', '\x1f', '\x44', // nop 0(%rax,%rax,1)
3989 const char nop6
[6] = { '\x66', '\x0f', '\x1f', // nopw 0(%rax,%rax,1)
3990 '\x44', '\x00', '\x00' };
3991 const char nop7
[7] = { '\x0f', '\x1f', '\x80', // nopl 0L(%rax)
3992 '\x00', '\x00', '\x00',
3994 const char nop8
[8] = { '\x0f', '\x1f', '\x84', // nopl 0L(%rax,%rax,1)
3995 '\x00', '\x00', '\x00',
3997 const char nop9
[9] = { '\x66', '\x0f', '\x1f', // nopw 0L(%rax,%rax,1)
3998 '\x84', '\x00', '\x00',
3999 '\x00', '\x00', '\x00' };
4000 const char nop10
[10] = { '\x66', '\x2e', '\x0f', // nopw %cs:0L(%rax,%rax,1)
4001 '\x1f', '\x84', '\x00',
4002 '\x00', '\x00', '\x00',
4004 const char nop11
[11] = { '\x66', '\x66', '\x2e', // data16
4005 '\x0f', '\x1f', '\x84', // nopw %cs:0L(%rax,%rax,1)
4006 '\x00', '\x00', '\x00',
4008 const char nop12
[12] = { '\x66', '\x66', '\x66', // data16; data16
4009 '\x2e', '\x0f', '\x1f', // nopw %cs:0L(%rax,%rax,1)
4010 '\x84', '\x00', '\x00',
4011 '\x00', '\x00', '\x00' };
4012 const char nop13
[13] = { '\x66', '\x66', '\x66', // data16; data16; data16
4013 '\x66', '\x2e', '\x0f', // nopw %cs:0L(%rax,%rax,1)
4014 '\x1f', '\x84', '\x00',
4015 '\x00', '\x00', '\x00',
4017 const char nop14
[14] = { '\x66', '\x66', '\x66', // data16; data16; data16
4018 '\x66', '\x66', '\x2e', // data16
4019 '\x0f', '\x1f', '\x84', // nopw %cs:0L(%rax,%rax,1)
4020 '\x00', '\x00', '\x00',
4022 const char nop15
[15] = { '\x66', '\x66', '\x66', // data16; data16; data16
4023 '\x66', '\x66', '\x66', // data16; data16
4024 '\x2e', '\x0f', '\x1f', // nopw %cs:0L(%rax,%rax,1)
4025 '\x84', '\x00', '\x00',
4026 '\x00', '\x00', '\x00' };
4028 const char* nops
[16] = {
4030 nop1
, nop2
, nop3
, nop4
, nop5
, nop6
, nop7
,
4031 nop8
, nop9
, nop10
, nop11
, nop12
, nop13
, nop14
, nop15
4034 return std::string(nops
[length
], length
);
4037 // Return the addend to use for a target specific relocation. The
4038 // only target specific relocation is R_X86_64_TLSDESC for a local
4039 // symbol. We want to set the addend is the offset of the local
4040 // symbol in the TLS segment.
4044 Target_x86_64
<size
>::do_reloc_addend(void* arg
, unsigned int r_type
,
4047 gold_assert(r_type
== elfcpp::R_X86_64_TLSDESC
);
4048 uintptr_t intarg
= reinterpret_cast<uintptr_t>(arg
);
4049 gold_assert(intarg
< this->tlsdesc_reloc_info_
.size());
4050 const Tlsdesc_info
& ti(this->tlsdesc_reloc_info_
[intarg
]);
4051 const Symbol_value
<size
>* psymval
= ti
.object
->local_symbol(ti
.r_sym
);
4052 gold_assert(psymval
->is_tls_symbol());
4053 // The value of a TLS symbol is the offset in the TLS segment.
4054 return psymval
->value(ti
.object
, 0);
4057 // Return the value to use for the base of a DW_EH_PE_datarel offset
4058 // in an FDE. Solaris and SVR4 use DW_EH_PE_datarel because their
4059 // assembler can not write out the difference between two labels in
4060 // different sections, so instead of using a pc-relative value they
4061 // use an offset from the GOT.
4065 Target_x86_64
<size
>::do_ehframe_datarel_base() const
4067 gold_assert(this->global_offset_table_
!= NULL
);
4068 Symbol
* sym
= this->global_offset_table_
;
4069 Sized_symbol
<size
>* ssym
= static_cast<Sized_symbol
<size
>*>(sym
);
4070 return ssym
->value();
4073 // FNOFFSET in section SHNDX in OBJECT is the start of a function
4074 // compiled with -fsplit-stack. The function calls non-split-stack
4075 // code. We have to change the function so that it always ensures
4076 // that it has enough stack space to run some random function.
4080 Target_x86_64
<size
>::do_calls_non_split(Relobj
* object
, unsigned int shndx
,
4081 section_offset_type fnoffset
,
4082 section_size_type fnsize
,
4083 unsigned char* view
,
4084 section_size_type view_size
,
4086 std::string
* to
) const
4088 // The function starts with a comparison of the stack pointer and a
4089 // field in the TCB. This is followed by a jump.
4092 if (this->match_view(view
, view_size
, fnoffset
, "\x64\x48\x3b\x24\x25", 5)
4095 // We will call __morestack if the carry flag is set after this
4096 // comparison. We turn the comparison into an stc instruction
4098 view
[fnoffset
] = '\xf9';
4099 this->set_view_to_nop(view
, view_size
, fnoffset
+ 1, 8);
4101 // lea NN(%rsp),%r10
4102 // lea NN(%rsp),%r11
4103 else if ((this->match_view(view
, view_size
, fnoffset
,
4104 "\x4c\x8d\x94\x24", 4)
4105 || this->match_view(view
, view_size
, fnoffset
,
4106 "\x4c\x8d\x9c\x24", 4))
4109 // This is loading an offset from the stack pointer for a
4110 // comparison. The offset is negative, so we decrease the
4111 // offset by the amount of space we need for the stack. This
4112 // means we will avoid calling __morestack if there happens to
4113 // be plenty of space on the stack already.
4114 unsigned char* pval
= view
+ fnoffset
+ 4;
4115 uint32_t val
= elfcpp::Swap_unaligned
<32, false>::readval(pval
);
4116 val
-= parameters
->options().split_stack_adjust_size();
4117 elfcpp::Swap_unaligned
<32, false>::writeval(pval
, val
);
4121 if (!object
->has_no_split_stack())
4122 object
->error(_("failed to match split-stack sequence at "
4123 "section %u offset %0zx"),
4124 shndx
, static_cast<size_t>(fnoffset
));
4128 // We have to change the function so that it calls
4129 // __morestack_non_split instead of __morestack. The former will
4130 // allocate additional stack space.
4131 *from
= "__morestack";
4132 *to
= "__morestack_non_split";
4135 // The selector for x86_64 object files.
4138 class Target_selector_x86_64
: public Target_selector_freebsd
4141 Target_selector_x86_64()
4142 : Target_selector_freebsd(elfcpp::EM_X86_64
, size
, false,
4144 ? "elf64-x86-64" : "elf32-x86-64"),
4146 ? "elf64-x86-64-freebsd"
4147 : "elf32-x86-64-freebsd"),
4148 (size
== 64 ? "elf_x86_64" : "elf32_x86_64"))
4152 do_instantiate_target()
4153 { return new Target_x86_64
<size
>(); }
4157 Target_selector_x86_64
<64> target_selector_x86_64
;
4158 Target_selector_x86_64
<32> target_selector_x32
;
4160 } // End anonymous namespace.