1 // x86_64.cc -- x86_64 target support for gold.
3 // Copyright 2006, 2007, 2008 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.
28 #include "parameters.h"
35 #include "copy-relocs.h"
37 #include "target-reloc.h"
38 #include "target-select.h"
46 class Output_data_plt_x86_64
;
48 // The x86_64 target class.
50 // http://www.x86-64.org/documentation/abi.pdf
51 // TLS info comes from
52 // http://people.redhat.com/drepper/tls.pdf
53 // http://www.lsd.ic.unicamp.br/~oliva/writeups/TLS/RFC-TLSDESC-x86.txt
55 class Target_x86_64
: public Sized_target
<64, false>
58 // In the x86_64 ABI (p 68), it says "The AMD64 ABI architectures
59 // uses only Elf64_Rela relocation entries with explicit addends."
60 typedef Output_data_reloc
<elfcpp::SHT_RELA
, true, 64, false> Reloc_section
;
63 : Sized_target
<64, false>(&x86_64_info
),
64 got_(NULL
), plt_(NULL
), got_plt_(NULL
), rela_dyn_(NULL
),
65 copy_relocs_(elfcpp::R_X86_64_COPY
), dynbss_(NULL
),
66 got_mod_index_offset_(-1U), tls_base_symbol_defined_(false)
69 // Scan the relocations to look for symbol adjustments.
71 scan_relocs(const General_options
& options
,
74 Sized_relobj
<64, false>* object
,
75 unsigned int data_shndx
,
77 const unsigned char* prelocs
,
79 Output_section
* output_section
,
80 bool needs_special_offset_handling
,
81 size_t local_symbol_count
,
82 const unsigned char* plocal_symbols
);
84 // Finalize the sections.
86 do_finalize_sections(Layout
*);
88 // Return the value to use for a dynamic which requires special
91 do_dynsym_value(const Symbol
*) const;
93 // Relocate a section.
95 relocate_section(const Relocate_info
<64, false>*,
97 const unsigned char* prelocs
,
99 Output_section
* output_section
,
100 bool needs_special_offset_handling
,
102 elfcpp::Elf_types
<64>::Elf_Addr view_address
,
103 section_size_type view_size
);
105 // Scan the relocs during a relocatable link.
107 scan_relocatable_relocs(const General_options
& options
,
108 Symbol_table
* symtab
,
110 Sized_relobj
<64, false>* object
,
111 unsigned int data_shndx
,
112 unsigned int sh_type
,
113 const unsigned char* prelocs
,
115 Output_section
* output_section
,
116 bool needs_special_offset_handling
,
117 size_t local_symbol_count
,
118 const unsigned char* plocal_symbols
,
119 Relocatable_relocs
*);
121 // Relocate a section during a relocatable link.
123 relocate_for_relocatable(const Relocate_info
<64, false>*,
124 unsigned int sh_type
,
125 const unsigned char* prelocs
,
127 Output_section
* output_section
,
128 off_t offset_in_output_section
,
129 const Relocatable_relocs
*,
131 elfcpp::Elf_types
<64>::Elf_Addr view_address
,
132 section_size_type view_size
,
133 unsigned char* reloc_view
,
134 section_size_type reloc_view_size
);
136 // Return a string used to fill a code section with nops.
138 do_code_fill(section_size_type length
) const;
140 // Return whether SYM is defined by the ABI.
142 do_is_defined_by_abi(Symbol
* sym
) const
143 { return strcmp(sym
->name(), "__tls_get_addr") == 0; }
145 // Return the size of the GOT section.
149 gold_assert(this->got_
!= NULL
);
150 return this->got_
->data_size();
154 // The class which scans relocations.
159 : issued_non_pic_error_(false)
163 local(const General_options
& options
, Symbol_table
* symtab
,
164 Layout
* layout
, Target_x86_64
* target
,
165 Sized_relobj
<64, false>* object
,
166 unsigned int data_shndx
,
167 Output_section
* output_section
,
168 const elfcpp::Rela
<64, false>& reloc
, unsigned int r_type
,
169 const elfcpp::Sym
<64, false>& lsym
);
172 global(const General_options
& options
, Symbol_table
* symtab
,
173 Layout
* layout
, Target_x86_64
* target
,
174 Sized_relobj
<64, false>* object
,
175 unsigned int data_shndx
,
176 Output_section
* output_section
,
177 const elfcpp::Rela
<64, false>& reloc
, unsigned int r_type
,
182 unsupported_reloc_local(Sized_relobj
<64, false>*, unsigned int r_type
);
185 unsupported_reloc_global(Sized_relobj
<64, false>*, unsigned int r_type
,
189 check_non_pic(Relobj
*, unsigned int r_type
);
191 // Whether we have issued an error about a non-PIC compilation.
192 bool issued_non_pic_error_
;
195 // The class which implements relocation.
200 : skip_call_tls_get_addr_(false)
205 if (this->skip_call_tls_get_addr_
)
207 // FIXME: This needs to specify the location somehow.
208 gold_error(_("missing expected TLS relocation"));
212 // Do a relocation. Return false if the caller should not issue
213 // any warnings about this relocation.
215 relocate(const Relocate_info
<64, false>*, Target_x86_64
*, size_t relnum
,
216 const elfcpp::Rela
<64, false>&,
217 unsigned int r_type
, const Sized_symbol
<64>*,
218 const Symbol_value
<64>*,
219 unsigned char*, elfcpp::Elf_types
<64>::Elf_Addr
,
223 // Do a TLS relocation.
225 relocate_tls(const Relocate_info
<64, false>*, Target_x86_64
*,
226 size_t relnum
, const elfcpp::Rela
<64, false>&,
227 unsigned int r_type
, const Sized_symbol
<64>*,
228 const Symbol_value
<64>*,
229 unsigned char*, elfcpp::Elf_types
<64>::Elf_Addr
,
232 // Do a TLS General-Dynamic to Initial-Exec transition.
234 tls_gd_to_ie(const Relocate_info
<64, false>*, size_t relnum
,
235 Output_segment
* tls_segment
,
236 const elfcpp::Rela
<64, false>&, unsigned int r_type
,
237 elfcpp::Elf_types
<64>::Elf_Addr value
,
239 elfcpp::Elf_types
<64>::Elf_Addr
,
240 section_size_type view_size
);
242 // Do a TLS General-Dynamic to Local-Exec transition.
244 tls_gd_to_le(const Relocate_info
<64, false>*, size_t relnum
,
245 Output_segment
* tls_segment
,
246 const elfcpp::Rela
<64, false>&, unsigned int r_type
,
247 elfcpp::Elf_types
<64>::Elf_Addr value
,
249 section_size_type view_size
);
251 // Do a TLSDESC-style General-Dynamic to Initial-Exec transition.
253 tls_desc_gd_to_ie(const Relocate_info
<64, false>*, size_t relnum
,
254 Output_segment
* tls_segment
,
255 const elfcpp::Rela
<64, false>&, unsigned int r_type
,
256 elfcpp::Elf_types
<64>::Elf_Addr value
,
258 elfcpp::Elf_types
<64>::Elf_Addr
,
259 section_size_type view_size
);
261 // Do a TLSDESC-style General-Dynamic to Local-Exec transition.
263 tls_desc_gd_to_le(const Relocate_info
<64, false>*, size_t relnum
,
264 Output_segment
* tls_segment
,
265 const elfcpp::Rela
<64, false>&, unsigned int r_type
,
266 elfcpp::Elf_types
<64>::Elf_Addr value
,
268 section_size_type view_size
);
270 // Do a TLS Local-Dynamic to Local-Exec transition.
272 tls_ld_to_le(const Relocate_info
<64, false>*, size_t relnum
,
273 Output_segment
* tls_segment
,
274 const elfcpp::Rela
<64, false>&, unsigned int r_type
,
275 elfcpp::Elf_types
<64>::Elf_Addr value
,
277 section_size_type view_size
);
279 // Do a TLS Initial-Exec to Local-Exec transition.
281 tls_ie_to_le(const Relocate_info
<64, false>*, size_t relnum
,
282 Output_segment
* tls_segment
,
283 const elfcpp::Rela
<64, false>&, unsigned int r_type
,
284 elfcpp::Elf_types
<64>::Elf_Addr value
,
286 section_size_type view_size
);
288 // This is set if we should skip the next reloc, which should be a
289 // PLT32 reloc against ___tls_get_addr.
290 bool skip_call_tls_get_addr_
;
293 // A class which returns the size required for a relocation type,
294 // used while scanning relocs during a relocatable link.
295 class Relocatable_size_for_reloc
299 get_size_for_reloc(unsigned int, Relobj
*);
302 // Adjust TLS relocation type based on the options and whether this
303 // is a local symbol.
304 static tls::Tls_optimization
305 optimize_tls_reloc(bool is_final
, int r_type
);
307 // Get the GOT section, creating it if necessary.
308 Output_data_got
<64, false>*
309 got_section(Symbol_table
*, Layout
*);
311 // Get the GOT PLT section.
313 got_plt_section() const
315 gold_assert(this->got_plt_
!= NULL
);
316 return this->got_plt_
;
319 // Create the PLT section.
321 make_plt_section(Symbol_table
* symtab
, Layout
* layout
);
323 // Create a PLT entry for a global symbol.
325 make_plt_entry(Symbol_table
*, Layout
*, Symbol
*);
327 // Define the _TLS_MODULE_BASE_ symbol at the end of the TLS segment.
329 define_tls_base_symbol(Symbol_table
*, Layout
*);
331 // Create the reserved PLT and GOT entries for the TLS descriptor resolver.
333 reserve_tlsdesc_entries(Symbol_table
* symtab
, Layout
* layout
);
335 // Create a GOT entry for the TLS module index.
337 got_mod_index_entry(Symbol_table
* symtab
, Layout
* layout
,
338 Sized_relobj
<64, false>* object
);
340 // Get the PLT section.
341 Output_data_plt_x86_64
*
344 gold_assert(this->plt_
!= NULL
);
348 // Get the dynamic reloc section, creating it if necessary.
350 rela_dyn_section(Layout
*);
352 // Return true if the symbol may need a COPY relocation.
353 // References from an executable object to non-function symbols
354 // defined in a dynamic object may need a COPY relocation.
356 may_need_copy_reloc(Symbol
* gsym
)
358 return (!parameters
->options().shared()
359 && gsym
->is_from_dynobj()
360 && gsym
->type() != elfcpp::STT_FUNC
);
363 // Add a potential copy relocation.
365 copy_reloc(Symbol_table
* symtab
, Layout
* layout
, Relobj
* object
,
366 unsigned int shndx
, Output_section
* output_section
,
367 Symbol
* sym
, const elfcpp::Rela
<64, false>& reloc
)
369 this->copy_relocs_
.copy_reloc(symtab
, layout
,
370 symtab
->get_sized_symbol
<64>(sym
),
371 object
, shndx
, output_section
,
372 reloc
, this->rela_dyn_section(layout
));
375 // Information about this specific target which we pass to the
376 // general Target structure.
377 static const Target::Target_info x86_64_info
;
381 GOT_TYPE_STANDARD
= 0, // GOT entry for a regular symbol
382 GOT_TYPE_TLS_OFFSET
= 1, // GOT entry for TLS offset
383 GOT_TYPE_TLS_PAIR
= 2, // GOT entry for TLS module/offset pair
384 GOT_TYPE_TLS_DESC
= 3 // GOT entry for TLS_DESC pair
388 Output_data_got
<64, false>* got_
;
390 Output_data_plt_x86_64
* plt_
;
391 // The GOT PLT section.
392 Output_data_space
* got_plt_
;
393 // The dynamic reloc section.
394 Reloc_section
* rela_dyn_
;
395 // Relocs saved to avoid a COPY reloc.
396 Copy_relocs
<elfcpp::SHT_RELA
, 64, false> copy_relocs_
;
397 // Space for variables copied with a COPY reloc.
398 Output_data_space
* dynbss_
;
399 // Offset of the GOT entry for the TLS module index.
400 unsigned int got_mod_index_offset_
;
401 // True if the _TLS_MODULE_BASE_ symbol has been defined.
402 bool tls_base_symbol_defined_
;
405 const Target::Target_info
Target_x86_64::x86_64_info
=
408 false, // is_big_endian
409 elfcpp::EM_X86_64
, // machine_code
410 false, // has_make_symbol
411 false, // has_resolve
412 true, // has_code_fill
413 true, // is_default_stack_executable
415 "/lib/ld64.so.1", // program interpreter
416 0x400000, // default_text_segment_address
417 0x1000, // abi_pagesize (overridable by -z max-page-size)
418 0x1000 // common_pagesize (overridable by -z common-page-size)
421 // Get the GOT section, creating it if necessary.
423 Output_data_got
<64, false>*
424 Target_x86_64::got_section(Symbol_table
* symtab
, Layout
* layout
)
426 if (this->got_
== NULL
)
428 gold_assert(symtab
!= NULL
&& layout
!= NULL
);
430 this->got_
= new Output_data_got
<64, false>();
432 layout
->add_output_section_data(".got", elfcpp::SHT_PROGBITS
,
433 elfcpp::SHF_ALLOC
| elfcpp::SHF_WRITE
,
436 // The old GNU linker creates a .got.plt section. We just
437 // create another set of data in the .got section. Note that we
438 // always create a PLT if we create a GOT, although the PLT
440 this->got_plt_
= new Output_data_space(8);
441 layout
->add_output_section_data(".got", elfcpp::SHT_PROGBITS
,
442 elfcpp::SHF_ALLOC
| elfcpp::SHF_WRITE
,
445 // The first three entries are reserved.
446 this->got_plt_
->set_current_data_size(3 * 8);
448 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
449 symtab
->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL
,
451 0, 0, elfcpp::STT_OBJECT
,
453 elfcpp::STV_HIDDEN
, 0,
460 // Get the dynamic reloc section, creating it if necessary.
462 Target_x86_64::Reloc_section
*
463 Target_x86_64::rela_dyn_section(Layout
* layout
)
465 if (this->rela_dyn_
== NULL
)
467 gold_assert(layout
!= NULL
);
468 this->rela_dyn_
= new Reloc_section(parameters
->options().combreloc());
469 layout
->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA
,
470 elfcpp::SHF_ALLOC
, this->rela_dyn_
);
472 return this->rela_dyn_
;
475 // A class to handle the PLT data.
477 class Output_data_plt_x86_64
: public Output_section_data
480 typedef Output_data_reloc
<elfcpp::SHT_RELA
, true, 64, false> Reloc_section
;
482 Output_data_plt_x86_64(Layout
*, Output_data_got
<64, false>*,
485 // Add an entry to the PLT.
487 add_entry(Symbol
* gsym
);
489 // Add the reserved TLSDESC_PLT entry to the PLT.
491 reserve_tlsdesc_entry(unsigned int got_offset
)
492 { this->tlsdesc_got_offset_
= got_offset
; }
494 // Return true if a TLSDESC_PLT entry has been reserved.
496 has_tlsdesc_entry() const
497 { return this->tlsdesc_got_offset_
!= -1U; }
499 // Return the GOT offset for the reserved TLSDESC_PLT entry.
501 get_tlsdesc_got_offset() const
502 { return this->tlsdesc_got_offset_
; }
504 // Return the offset of the reserved TLSDESC_PLT entry.
506 get_tlsdesc_plt_offset() const
507 { return (this->count_
+ 1) * plt_entry_size
; }
509 // Return the .rel.plt section data.
512 { return this->rel_
; }
516 do_adjust_output_section(Output_section
* os
);
519 // The size of an entry in the PLT.
520 static const int plt_entry_size
= 16;
522 // The first entry in the PLT.
523 // From the AMD64 ABI: "Unlike Intel386 ABI, this ABI uses the same
524 // procedure linkage table for both programs and shared objects."
525 static unsigned char first_plt_entry
[plt_entry_size
];
527 // Other entries in the PLT for an executable.
528 static unsigned char plt_entry
[plt_entry_size
];
530 // The reserved TLSDESC entry in the PLT for an executable.
531 static unsigned char tlsdesc_plt_entry
[plt_entry_size
];
533 // Set the final size.
535 set_final_data_size();
537 // Write out the PLT data.
539 do_write(Output_file
*);
541 // The reloc section.
544 Output_data_got
<64, false>* got_
;
545 // The .got.plt section.
546 Output_data_space
* got_plt_
;
547 // The number of PLT entries.
549 // Offset of the reserved TLSDESC_GOT entry when needed.
550 unsigned int tlsdesc_got_offset_
;
553 // Create the PLT section. The ordinary .got section is an argument,
554 // since we need to refer to the start. We also create our own .got
555 // section just for PLT entries.
557 Output_data_plt_x86_64::Output_data_plt_x86_64(Layout
* layout
,
558 Output_data_got
<64, false>* got
,
559 Output_data_space
* got_plt
)
560 : Output_section_data(8), got_(got
), got_plt_(got_plt
), count_(0),
561 tlsdesc_got_offset_(-1U)
563 this->rel_
= new Reloc_section(false);
564 layout
->add_output_section_data(".rela.plt", elfcpp::SHT_RELA
,
565 elfcpp::SHF_ALLOC
, this->rel_
);
569 Output_data_plt_x86_64::do_adjust_output_section(Output_section
* os
)
571 // UnixWare sets the entsize of .plt to 4, and so does the old GNU
572 // linker, and so do we.
576 // Add an entry to the PLT.
579 Output_data_plt_x86_64::add_entry(Symbol
* gsym
)
581 gold_assert(!gsym
->has_plt_offset());
583 // Note that when setting the PLT offset we skip the initial
584 // reserved PLT entry.
585 gsym
->set_plt_offset((this->count_
+ 1) * plt_entry_size
);
589 section_offset_type got_offset
= this->got_plt_
->current_data_size();
591 // Every PLT entry needs a GOT entry which points back to the PLT
592 // entry (this will be changed by the dynamic linker, normally
593 // lazily when the function is called).
594 this->got_plt_
->set_current_data_size(got_offset
+ 8);
596 // Every PLT entry needs a reloc.
597 gsym
->set_needs_dynsym_entry();
598 this->rel_
->add_global(gsym
, elfcpp::R_X86_64_JUMP_SLOT
, this->got_plt_
,
601 // Note that we don't need to save the symbol. The contents of the
602 // PLT are independent of which symbols are used. The symbols only
603 // appear in the relocations.
606 // Set the final size.
608 Output_data_plt_x86_64::set_final_data_size()
610 unsigned int count
= this->count_
;
611 if (this->has_tlsdesc_entry())
613 this->set_data_size((count
+ 1) * plt_entry_size
);
616 // The first entry in the PLT for an executable.
618 unsigned char Output_data_plt_x86_64::first_plt_entry
[plt_entry_size
] =
620 // From AMD64 ABI Draft 0.98, page 76
621 0xff, 0x35, // pushq contents of memory address
622 0, 0, 0, 0, // replaced with address of .got + 8
623 0xff, 0x25, // jmp indirect
624 0, 0, 0, 0, // replaced with address of .got + 16
625 0x90, 0x90, 0x90, 0x90 // noop (x4)
628 // Subsequent entries in the PLT for an executable.
630 unsigned char Output_data_plt_x86_64::plt_entry
[plt_entry_size
] =
632 // From AMD64 ABI Draft 0.98, page 76
633 0xff, 0x25, // jmpq indirect
634 0, 0, 0, 0, // replaced with address of symbol in .got
635 0x68, // pushq immediate
636 0, 0, 0, 0, // replaced with offset into relocation table
637 0xe9, // jmpq relative
638 0, 0, 0, 0 // replaced with offset to start of .plt
641 // The reserved TLSDESC entry in the PLT for an executable.
643 unsigned char Output_data_plt_x86_64::tlsdesc_plt_entry
[plt_entry_size
] =
645 // From Alexandre Oliva, "Thread-Local Storage Descriptors for IA32
646 // and AMD64/EM64T", Version 0.9.4 (2005-10-10).
647 0xff, 0x35, // pushq x(%rip)
648 0, 0, 0, 0, // replaced with address of linkmap GOT entry (at PLTGOT + 8)
649 0xff, 0x25, // jmpq *y(%rip)
650 0, 0, 0, 0, // replaced with offset of reserved TLSDESC_GOT entry
655 // Write out the PLT. This uses the hand-coded instructions above,
656 // and adjusts them as needed. This is specified by the AMD64 ABI.
659 Output_data_plt_x86_64::do_write(Output_file
* of
)
661 const off_t offset
= this->offset();
662 const section_size_type oview_size
=
663 convert_to_section_size_type(this->data_size());
664 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
666 const off_t got_file_offset
= this->got_plt_
->offset();
667 const section_size_type got_size
=
668 convert_to_section_size_type(this->got_plt_
->data_size());
669 unsigned char* const got_view
= of
->get_output_view(got_file_offset
,
672 unsigned char* pov
= oview
;
674 // The base address of the .plt section.
675 elfcpp::Elf_types
<64>::Elf_Addr plt_address
= this->address();
676 // The base address of the .got section.
677 elfcpp::Elf_types
<64>::Elf_Addr got_base
= this->got_
->address();
678 // The base address of the PLT portion of the .got section,
679 // which is where the GOT pointer will point, and where the
680 // three reserved GOT entries are located.
681 elfcpp::Elf_types
<64>::Elf_Addr got_address
= this->got_plt_
->address();
683 memcpy(pov
, first_plt_entry
, plt_entry_size
);
684 // We do a jmp relative to the PC at the end of this instruction.
685 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
687 - (plt_address
+ 6)));
688 elfcpp::Swap
<32, false>::writeval(pov
+ 8,
690 - (plt_address
+ 12)));
691 pov
+= plt_entry_size
;
693 unsigned char* got_pov
= got_view
;
695 memset(got_pov
, 0, 24);
698 unsigned int plt_offset
= plt_entry_size
;
699 unsigned int got_offset
= 24;
700 const unsigned int count
= this->count_
;
701 for (unsigned int plt_index
= 0;
704 pov
+= plt_entry_size
,
706 plt_offset
+= plt_entry_size
,
709 // Set and adjust the PLT entry itself.
710 memcpy(pov
, plt_entry
, plt_entry_size
);
711 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
712 (got_address
+ got_offset
713 - (plt_address
+ plt_offset
716 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 7, plt_index
);
717 elfcpp::Swap
<32, false>::writeval(pov
+ 12,
718 - (plt_offset
+ plt_entry_size
));
720 // Set the entry in the GOT.
721 elfcpp::Swap
<64, false>::writeval(got_pov
, plt_address
+ plt_offset
+ 6);
724 if (this->has_tlsdesc_entry())
726 // Set and adjust the reserved TLSDESC PLT entry.
727 unsigned int tlsdesc_got_offset
= this->get_tlsdesc_got_offset();
728 memcpy(pov
, tlsdesc_plt_entry
, plt_entry_size
);
729 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
731 - (plt_address
+ plt_offset
733 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 8,
736 - (plt_address
+ plt_offset
738 pov
+= plt_entry_size
;
741 gold_assert(static_cast<section_size_type
>(pov
- oview
) == oview_size
);
742 gold_assert(static_cast<section_size_type
>(got_pov
- got_view
) == got_size
);
744 of
->write_output_view(offset
, oview_size
, oview
);
745 of
->write_output_view(got_file_offset
, got_size
, got_view
);
748 // Create the PLT section.
751 Target_x86_64::make_plt_section(Symbol_table
* symtab
, Layout
* layout
)
753 if (this->plt_
== NULL
)
755 // Create the GOT sections first.
756 this->got_section(symtab
, layout
);
758 this->plt_
= new Output_data_plt_x86_64(layout
, this->got_
,
760 layout
->add_output_section_data(".plt", elfcpp::SHT_PROGBITS
,
762 | elfcpp::SHF_EXECINSTR
),
767 // Create a PLT entry for a global symbol.
770 Target_x86_64::make_plt_entry(Symbol_table
* symtab
, Layout
* layout
,
773 if (gsym
->has_plt_offset())
776 if (this->plt_
== NULL
)
777 this->make_plt_section(symtab
, layout
);
779 this->plt_
->add_entry(gsym
);
782 // Define the _TLS_MODULE_BASE_ symbol at the end of the TLS segment.
785 Target_x86_64::define_tls_base_symbol(Symbol_table
* symtab
, Layout
* layout
)
787 if (this->tls_base_symbol_defined_
)
790 Output_segment
* tls_segment
= layout
->tls_segment();
791 if (tls_segment
!= NULL
)
793 symtab
->define_in_output_segment("_TLS_MODULE_BASE_", NULL
,
797 elfcpp::STV_HIDDEN
, 0,
798 Symbol::SEGMENT_END
, true);
800 this->tls_base_symbol_defined_
= true;
803 // Create the reserved PLT and GOT entries for the TLS descriptor resolver.
806 Target_x86_64::reserve_tlsdesc_entries(Symbol_table
* symtab
,
809 if (this->plt_
== NULL
)
810 this->make_plt_section(symtab
, layout
);
812 if (!this->plt_
->has_tlsdesc_entry())
814 // Allocate the TLSDESC_GOT entry.
815 Output_data_got
<64, false>* got
= this->got_section(symtab
, layout
);
816 unsigned int got_offset
= got
->add_constant(0);
818 // Allocate the TLSDESC_PLT entry.
819 this->plt_
->reserve_tlsdesc_entry(got_offset
);
823 // Create a GOT entry for the TLS module index.
826 Target_x86_64::got_mod_index_entry(Symbol_table
* symtab
, Layout
* layout
,
827 Sized_relobj
<64, false>* object
)
829 if (this->got_mod_index_offset_
== -1U)
831 gold_assert(symtab
!= NULL
&& layout
!= NULL
&& object
!= NULL
);
832 Reloc_section
* rela_dyn
= this->rela_dyn_section(layout
);
833 Output_data_got
<64, false>* got
= this->got_section(symtab
, layout
);
834 unsigned int got_offset
= got
->add_constant(0);
835 rela_dyn
->add_local(object
, 0, elfcpp::R_X86_64_DTPMOD64
, got
,
837 got
->add_constant(0);
838 this->got_mod_index_offset_
= got_offset
;
840 return this->got_mod_index_offset_
;
843 // Optimize the TLS relocation type based on what we know about the
844 // symbol. IS_FINAL is true if the final address of this symbol is
845 // known at link time.
847 tls::Tls_optimization
848 Target_x86_64::optimize_tls_reloc(bool is_final
, int r_type
)
850 // If we are generating a shared library, then we can't do anything
852 if (parameters
->options().shared())
853 return tls::TLSOPT_NONE
;
857 case elfcpp::R_X86_64_TLSGD
:
858 case elfcpp::R_X86_64_GOTPC32_TLSDESC
:
859 case elfcpp::R_X86_64_TLSDESC_CALL
:
860 // These are General-Dynamic which permits fully general TLS
861 // access. Since we know that we are generating an executable,
862 // we can convert this to Initial-Exec. If we also know that
863 // this is a local symbol, we can further switch to Local-Exec.
865 return tls::TLSOPT_TO_LE
;
866 return tls::TLSOPT_TO_IE
;
868 case elfcpp::R_X86_64_TLSLD
:
869 // This is Local-Dynamic, which refers to a local symbol in the
870 // dynamic TLS block. Since we know that we generating an
871 // executable, we can switch to Local-Exec.
872 return tls::TLSOPT_TO_LE
;
874 case elfcpp::R_X86_64_DTPOFF32
:
875 case elfcpp::R_X86_64_DTPOFF64
:
876 // Another Local-Dynamic reloc.
877 return tls::TLSOPT_TO_LE
;
879 case elfcpp::R_X86_64_GOTTPOFF
:
880 // These are Initial-Exec relocs which get the thread offset
881 // from the GOT. If we know that we are linking against the
882 // local symbol, we can switch to Local-Exec, which links the
883 // thread offset into the instruction.
885 return tls::TLSOPT_TO_LE
;
886 return tls::TLSOPT_NONE
;
888 case elfcpp::R_X86_64_TPOFF32
:
889 // When we already have Local-Exec, there is nothing further we
891 return tls::TLSOPT_NONE
;
898 // Report an unsupported relocation against a local symbol.
901 Target_x86_64::Scan::unsupported_reloc_local(Sized_relobj
<64, false>* object
,
904 gold_error(_("%s: unsupported reloc %u against local symbol"),
905 object
->name().c_str(), r_type
);
908 // We are about to emit a dynamic relocation of type R_TYPE. If the
909 // dynamic linker does not support it, issue an error. The GNU linker
910 // only issues a non-PIC error for an allocated read-only section.
911 // Here we know the section is allocated, but we don't know that it is
912 // read-only. But we check for all the relocation types which the
913 // glibc dynamic linker supports, so it seems appropriate to issue an
914 // error even if the section is not read-only.
917 Target_x86_64::Scan::check_non_pic(Relobj
* object
, unsigned int r_type
)
921 // These are the relocation types supported by glibc for x86_64.
922 case elfcpp::R_X86_64_RELATIVE
:
923 case elfcpp::R_X86_64_GLOB_DAT
:
924 case elfcpp::R_X86_64_JUMP_SLOT
:
925 case elfcpp::R_X86_64_DTPMOD64
:
926 case elfcpp::R_X86_64_DTPOFF64
:
927 case elfcpp::R_X86_64_TPOFF64
:
928 case elfcpp::R_X86_64_64
:
929 case elfcpp::R_X86_64_32
:
930 case elfcpp::R_X86_64_PC32
:
931 case elfcpp::R_X86_64_COPY
:
935 // This prevents us from issuing more than one error per reloc
936 // section. But we can still wind up issuing more than one
937 // error per object file.
938 if (this->issued_non_pic_error_
)
940 object
->error(_("requires unsupported dynamic reloc; "
941 "recompile with -fPIC"));
942 this->issued_non_pic_error_
= true;
945 case elfcpp::R_X86_64_NONE
:
950 // Scan a relocation for a local symbol.
953 Target_x86_64::Scan::local(const General_options
&,
954 Symbol_table
* symtab
,
956 Target_x86_64
* target
,
957 Sized_relobj
<64, false>* object
,
958 unsigned int data_shndx
,
959 Output_section
* output_section
,
960 const elfcpp::Rela
<64, false>& reloc
,
962 const elfcpp::Sym
<64, false>& lsym
)
966 case elfcpp::R_X86_64_NONE
:
967 case elfcpp::R_386_GNU_VTINHERIT
:
968 case elfcpp::R_386_GNU_VTENTRY
:
971 case elfcpp::R_X86_64_64
:
972 // If building a shared library (or a position-independent
973 // executable), we need to create a dynamic relocation for this
974 // location. The relocation applied at link time will apply the
975 // link-time value, so we flag the location with an
976 // R_X86_64_RELATIVE relocation so the dynamic loader can
977 // relocate it easily.
978 if (parameters
->options().output_is_position_independent())
980 unsigned int r_sym
= elfcpp::elf_r_sym
<64>(reloc
.get_r_info());
981 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
982 rela_dyn
->add_local_relative(object
, r_sym
,
983 elfcpp::R_X86_64_RELATIVE
,
984 output_section
, data_shndx
,
985 reloc
.get_r_offset(),
986 reloc
.get_r_addend());
990 case elfcpp::R_X86_64_32
:
991 case elfcpp::R_X86_64_32S
:
992 case elfcpp::R_X86_64_16
:
993 case elfcpp::R_X86_64_8
:
994 // If building a shared library (or a position-independent
995 // executable), we need to create a dynamic relocation for this
996 // location. We can't use an R_X86_64_RELATIVE relocation
997 // because that is always a 64-bit relocation.
998 if (parameters
->options().output_is_position_independent())
1000 this->check_non_pic(object
, r_type
);
1002 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
1003 unsigned int r_sym
= elfcpp::elf_r_sym
<64>(reloc
.get_r_info());
1004 if (lsym
.get_st_type() != elfcpp::STT_SECTION
)
1005 rela_dyn
->add_local(object
, r_sym
, r_type
, output_section
,
1006 data_shndx
, reloc
.get_r_offset(),
1007 reloc
.get_r_addend());
1010 gold_assert(lsym
.get_st_value() == 0);
1011 unsigned int shndx
= lsym
.get_st_shndx();
1013 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
,
1016 object
->error(_("section symbol %u has bad shndx %u"),
1019 rela_dyn
->add_local_section(object
, shndx
,
1020 r_type
, output_section
,
1021 data_shndx
, reloc
.get_r_offset(),
1022 reloc
.get_r_addend());
1027 case elfcpp::R_X86_64_PC64
:
1028 case elfcpp::R_X86_64_PC32
:
1029 case elfcpp::R_X86_64_PC16
:
1030 case elfcpp::R_X86_64_PC8
:
1033 case elfcpp::R_X86_64_PLT32
:
1034 // Since we know this is a local symbol, we can handle this as a
1038 case elfcpp::R_X86_64_GOTPC32
:
1039 case elfcpp::R_X86_64_GOTOFF64
:
1040 case elfcpp::R_X86_64_GOTPC64
:
1041 case elfcpp::R_X86_64_PLTOFF64
:
1042 // We need a GOT section.
1043 target
->got_section(symtab
, layout
);
1044 // For PLTOFF64, we'd normally want a PLT section, but since we
1045 // know this is a local symbol, no PLT is needed.
1048 case elfcpp::R_X86_64_GOT64
:
1049 case elfcpp::R_X86_64_GOT32
:
1050 case elfcpp::R_X86_64_GOTPCREL64
:
1051 case elfcpp::R_X86_64_GOTPCREL
:
1052 case elfcpp::R_X86_64_GOTPLT64
:
1054 // The symbol requires a GOT entry.
1055 Output_data_got
<64, false>* got
= target
->got_section(symtab
, layout
);
1056 unsigned int r_sym
= elfcpp::elf_r_sym
<64>(reloc
.get_r_info());
1057 if (got
->add_local(object
, r_sym
, GOT_TYPE_STANDARD
))
1059 // If we are generating a shared object, we need to add a
1060 // dynamic relocation for this symbol's GOT entry.
1061 if (parameters
->options().output_is_position_independent())
1063 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
1064 // R_X86_64_RELATIVE assumes a 64-bit relocation.
1065 if (r_type
!= elfcpp::R_X86_64_GOT32
)
1066 rela_dyn
->add_local_relative(
1067 object
, r_sym
, elfcpp::R_X86_64_RELATIVE
, got
,
1068 object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
), 0);
1071 this->check_non_pic(object
, r_type
);
1073 gold_assert(lsym
.get_st_type() != elfcpp::STT_SECTION
);
1074 rela_dyn
->add_local(
1075 object
, r_sym
, r_type
, got
,
1076 object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
), 0);
1080 // For GOTPLT64, we'd normally want a PLT section, but since
1081 // we know this is a local symbol, no PLT is needed.
1085 case elfcpp::R_X86_64_COPY
:
1086 case elfcpp::R_X86_64_GLOB_DAT
:
1087 case elfcpp::R_X86_64_JUMP_SLOT
:
1088 case elfcpp::R_X86_64_RELATIVE
:
1089 // These are outstanding tls relocs, which are unexpected when linking
1090 case elfcpp::R_X86_64_TPOFF64
:
1091 case elfcpp::R_X86_64_DTPMOD64
:
1092 case elfcpp::R_X86_64_TLSDESC
:
1093 gold_error(_("%s: unexpected reloc %u in object file"),
1094 object
->name().c_str(), r_type
);
1097 // These are initial tls relocs, which are expected when linking
1098 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
1099 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
1100 case elfcpp::R_X86_64_TLSDESC_CALL
:
1101 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
1102 case elfcpp::R_X86_64_DTPOFF32
:
1103 case elfcpp::R_X86_64_DTPOFF64
:
1104 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
1105 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
1107 bool output_is_shared
= parameters
->options().shared();
1108 const tls::Tls_optimization optimized_type
1109 = Target_x86_64::optimize_tls_reloc(!output_is_shared
, r_type
);
1112 case elfcpp::R_X86_64_TLSGD
: // General-dynamic
1113 if (optimized_type
== tls::TLSOPT_NONE
)
1115 // Create a pair of GOT entries for the module index and
1116 // dtv-relative offset.
1117 Output_data_got
<64, false>* got
1118 = target
->got_section(symtab
, layout
);
1119 unsigned int r_sym
= elfcpp::elf_r_sym
<64>(reloc
.get_r_info());
1120 unsigned int shndx
= lsym
.get_st_shndx();
1122 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
, &is_ordinary
);
1124 object
->error(_("local symbol %u has bad shndx %u"),
1127 got
->add_local_pair_with_rela(object
, r_sym
,
1130 target
->rela_dyn_section(layout
),
1131 elfcpp::R_X86_64_DTPMOD64
, 0);
1133 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1134 unsupported_reloc_local(object
, r_type
);
1137 case elfcpp::R_X86_64_GOTPC32_TLSDESC
:
1138 target
->define_tls_base_symbol(symtab
, layout
);
1139 if (optimized_type
== tls::TLSOPT_NONE
)
1141 // Create reserved PLT and GOT entries for the resolver.
1142 target
->reserve_tlsdesc_entries(symtab
, layout
);
1144 // Generate a double GOT entry with an R_X86_64_TLSDESC reloc.
1145 Output_data_got
<64, false>* got
1146 = target
->got_section(symtab
, layout
);
1147 unsigned int r_sym
= elfcpp::elf_r_sym
<64>(reloc
.get_r_info());
1148 unsigned int shndx
= lsym
.get_st_shndx();
1150 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
, &is_ordinary
);
1152 object
->error(_("local symbol %u has bad shndx %u"),
1155 got
->add_local_pair_with_rela(object
, r_sym
,
1158 target
->rela_dyn_section(layout
),
1159 elfcpp::R_X86_64_TLSDESC
, 0);
1161 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1162 unsupported_reloc_local(object
, r_type
);
1165 case elfcpp::R_X86_64_TLSDESC_CALL
:
1168 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
1169 if (optimized_type
== tls::TLSOPT_NONE
)
1171 // Create a GOT entry for the module index.
1172 target
->got_mod_index_entry(symtab
, layout
, object
);
1174 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1175 unsupported_reloc_local(object
, r_type
);
1178 case elfcpp::R_X86_64_DTPOFF32
:
1179 case elfcpp::R_X86_64_DTPOFF64
:
1182 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
1183 layout
->set_has_static_tls();
1184 if (optimized_type
== tls::TLSOPT_NONE
)
1186 // Create a GOT entry for the tp-relative offset.
1187 Output_data_got
<64, false>* got
1188 = target
->got_section(symtab
, layout
);
1189 unsigned int r_sym
= elfcpp::elf_r_sym
<64>(reloc
.get_r_info());
1190 got
->add_local_with_rela(object
, r_sym
, GOT_TYPE_TLS_OFFSET
,
1191 target
->rela_dyn_section(layout
),
1192 elfcpp::R_X86_64_TPOFF64
);
1194 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1195 unsupported_reloc_local(object
, r_type
);
1198 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
1199 layout
->set_has_static_tls();
1200 if (output_is_shared
)
1201 unsupported_reloc_local(object
, r_type
);
1210 case elfcpp::R_X86_64_SIZE32
:
1211 case elfcpp::R_X86_64_SIZE64
:
1213 gold_error(_("%s: unsupported reloc %u against local symbol"),
1214 object
->name().c_str(), r_type
);
1220 // Report an unsupported relocation against a global symbol.
1223 Target_x86_64::Scan::unsupported_reloc_global(Sized_relobj
<64, false>* object
,
1224 unsigned int r_type
,
1227 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
1228 object
->name().c_str(), r_type
, gsym
->demangled_name().c_str());
1231 // Scan a relocation for a global symbol.
1234 Target_x86_64::Scan::global(const General_options
&,
1235 Symbol_table
* symtab
,
1237 Target_x86_64
* target
,
1238 Sized_relobj
<64, false>* object
,
1239 unsigned int data_shndx
,
1240 Output_section
* output_section
,
1241 const elfcpp::Rela
<64, false>& reloc
,
1242 unsigned int r_type
,
1247 case elfcpp::R_X86_64_NONE
:
1248 case elfcpp::R_386_GNU_VTINHERIT
:
1249 case elfcpp::R_386_GNU_VTENTRY
:
1252 case elfcpp::R_X86_64_64
:
1253 case elfcpp::R_X86_64_32
:
1254 case elfcpp::R_X86_64_32S
:
1255 case elfcpp::R_X86_64_16
:
1256 case elfcpp::R_X86_64_8
:
1258 // Make a PLT entry if necessary.
1259 if (gsym
->needs_plt_entry())
1261 target
->make_plt_entry(symtab
, layout
, gsym
);
1262 // Since this is not a PC-relative relocation, we may be
1263 // taking the address of a function. In that case we need to
1264 // set the entry in the dynamic symbol table to the address of
1266 if (gsym
->is_from_dynobj() && !parameters
->options().shared())
1267 gsym
->set_needs_dynsym_value();
1269 // Make a dynamic relocation if necessary.
1270 if (gsym
->needs_dynamic_reloc(Symbol::ABSOLUTE_REF
))
1272 if (target
->may_need_copy_reloc(gsym
))
1274 target
->copy_reloc(symtab
, layout
, object
,
1275 data_shndx
, output_section
, gsym
, reloc
);
1277 else if (r_type
== elfcpp::R_X86_64_64
1278 && gsym
->can_use_relative_reloc(false))
1280 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
1281 rela_dyn
->add_global_relative(gsym
, elfcpp::R_X86_64_RELATIVE
,
1282 output_section
, object
,
1283 data_shndx
, reloc
.get_r_offset(),
1284 reloc
.get_r_addend());
1288 this->check_non_pic(object
, r_type
);
1289 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
1290 rela_dyn
->add_global(gsym
, r_type
, output_section
, object
,
1291 data_shndx
, reloc
.get_r_offset(),
1292 reloc
.get_r_addend());
1298 case elfcpp::R_X86_64_PC64
:
1299 case elfcpp::R_X86_64_PC32
:
1300 case elfcpp::R_X86_64_PC16
:
1301 case elfcpp::R_X86_64_PC8
:
1303 // Make a PLT entry if necessary.
1304 if (gsym
->needs_plt_entry())
1305 target
->make_plt_entry(symtab
, layout
, gsym
);
1306 // Make a dynamic relocation if necessary.
1307 int flags
= Symbol::NON_PIC_REF
;
1308 if (gsym
->type() == elfcpp::STT_FUNC
)
1309 flags
|= Symbol::FUNCTION_CALL
;
1310 if (gsym
->needs_dynamic_reloc(flags
))
1312 if (target
->may_need_copy_reloc(gsym
))
1314 target
->copy_reloc(symtab
, layout
, object
,
1315 data_shndx
, output_section
, gsym
, reloc
);
1319 this->check_non_pic(object
, r_type
);
1320 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
1321 rela_dyn
->add_global(gsym
, r_type
, output_section
, object
,
1322 data_shndx
, reloc
.get_r_offset(),
1323 reloc
.get_r_addend());
1329 case elfcpp::R_X86_64_GOT64
:
1330 case elfcpp::R_X86_64_GOT32
:
1331 case elfcpp::R_X86_64_GOTPCREL64
:
1332 case elfcpp::R_X86_64_GOTPCREL
:
1333 case elfcpp::R_X86_64_GOTPLT64
:
1335 // The symbol requires a GOT entry.
1336 Output_data_got
<64, false>* got
= target
->got_section(symtab
, layout
);
1337 if (gsym
->final_value_is_known())
1338 got
->add_global(gsym
, GOT_TYPE_STANDARD
);
1341 // If this symbol is not fully resolved, we need to add a
1342 // dynamic relocation for it.
1343 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
1344 if (gsym
->is_from_dynobj()
1345 || gsym
->is_undefined()
1346 || gsym
->is_preemptible())
1347 got
->add_global_with_rela(gsym
, GOT_TYPE_STANDARD
, rela_dyn
,
1348 elfcpp::R_X86_64_GLOB_DAT
);
1351 if (got
->add_global(gsym
, GOT_TYPE_STANDARD
))
1352 rela_dyn
->add_global_relative(
1353 gsym
, elfcpp::R_X86_64_RELATIVE
, got
,
1354 gsym
->got_offset(GOT_TYPE_STANDARD
), 0);
1357 // For GOTPLT64, we also need a PLT entry (but only if the
1358 // symbol is not fully resolved).
1359 if (r_type
== elfcpp::R_X86_64_GOTPLT64
1360 && !gsym
->final_value_is_known())
1361 target
->make_plt_entry(symtab
, layout
, gsym
);
1365 case elfcpp::R_X86_64_PLT32
:
1366 // If the symbol is fully resolved, this is just a PC32 reloc.
1367 // Otherwise we need a PLT entry.
1368 if (gsym
->final_value_is_known())
1370 // If building a shared library, we can also skip the PLT entry
1371 // if the symbol is defined in the output file and is protected
1373 if (gsym
->is_defined()
1374 && !gsym
->is_from_dynobj()
1375 && !gsym
->is_preemptible())
1377 target
->make_plt_entry(symtab
, layout
, gsym
);
1380 case elfcpp::R_X86_64_GOTPC32
:
1381 case elfcpp::R_X86_64_GOTOFF64
:
1382 case elfcpp::R_X86_64_GOTPC64
:
1383 case elfcpp::R_X86_64_PLTOFF64
:
1384 // We need a GOT section.
1385 target
->got_section(symtab
, layout
);
1386 // For PLTOFF64, we also need a PLT entry (but only if the
1387 // symbol is not fully resolved).
1388 if (r_type
== elfcpp::R_X86_64_PLTOFF64
1389 && !gsym
->final_value_is_known())
1390 target
->make_plt_entry(symtab
, layout
, gsym
);
1393 case elfcpp::R_X86_64_COPY
:
1394 case elfcpp::R_X86_64_GLOB_DAT
:
1395 case elfcpp::R_X86_64_JUMP_SLOT
:
1396 case elfcpp::R_X86_64_RELATIVE
:
1397 // These are outstanding tls relocs, which are unexpected when linking
1398 case elfcpp::R_X86_64_TPOFF64
:
1399 case elfcpp::R_X86_64_DTPMOD64
:
1400 case elfcpp::R_X86_64_TLSDESC
:
1401 gold_error(_("%s: unexpected reloc %u in object file"),
1402 object
->name().c_str(), r_type
);
1405 // These are initial tls relocs, which are expected for global()
1406 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
1407 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
1408 case elfcpp::R_X86_64_TLSDESC_CALL
:
1409 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
1410 case elfcpp::R_X86_64_DTPOFF32
:
1411 case elfcpp::R_X86_64_DTPOFF64
:
1412 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
1413 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
1415 const bool is_final
= gsym
->final_value_is_known();
1416 const tls::Tls_optimization optimized_type
1417 = Target_x86_64::optimize_tls_reloc(is_final
, r_type
);
1420 case elfcpp::R_X86_64_TLSGD
: // General-dynamic
1421 if (optimized_type
== tls::TLSOPT_NONE
)
1423 // Create a pair of GOT entries for the module index and
1424 // dtv-relative offset.
1425 Output_data_got
<64, false>* got
1426 = target
->got_section(symtab
, layout
);
1427 got
->add_global_pair_with_rela(gsym
, GOT_TYPE_TLS_PAIR
,
1428 target
->rela_dyn_section(layout
),
1429 elfcpp::R_X86_64_DTPMOD64
,
1430 elfcpp::R_X86_64_DTPOFF64
);
1432 else if (optimized_type
== tls::TLSOPT_TO_IE
)
1434 // Create a GOT entry for the tp-relative offset.
1435 Output_data_got
<64, false>* got
1436 = target
->got_section(symtab
, layout
);
1437 got
->add_global_with_rela(gsym
, GOT_TYPE_TLS_OFFSET
,
1438 target
->rela_dyn_section(layout
),
1439 elfcpp::R_X86_64_TPOFF64
);
1441 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1442 unsupported_reloc_global(object
, r_type
, gsym
);
1445 case elfcpp::R_X86_64_GOTPC32_TLSDESC
:
1446 target
->define_tls_base_symbol(symtab
, layout
);
1447 if (optimized_type
== tls::TLSOPT_NONE
)
1449 // Create reserved PLT and GOT entries for the resolver.
1450 target
->reserve_tlsdesc_entries(symtab
, layout
);
1452 // Create a double GOT entry with an R_X86_64_TLSDESC reloc.
1453 Output_data_got
<64, false>* got
1454 = target
->got_section(symtab
, layout
);
1455 got
->add_global_pair_with_rela(gsym
, GOT_TYPE_TLS_DESC
,
1456 target
->rela_dyn_section(layout
),
1457 elfcpp::R_X86_64_TLSDESC
, 0);
1459 else if (optimized_type
== tls::TLSOPT_TO_IE
)
1461 // Create a GOT entry for the tp-relative offset.
1462 Output_data_got
<64, false>* got
1463 = target
->got_section(symtab
, layout
);
1464 got
->add_global_with_rela(gsym
, GOT_TYPE_TLS_OFFSET
,
1465 target
->rela_dyn_section(layout
),
1466 elfcpp::R_X86_64_TPOFF64
);
1468 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1469 unsupported_reloc_global(object
, r_type
, gsym
);
1472 case elfcpp::R_X86_64_TLSDESC_CALL
:
1475 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
1476 if (optimized_type
== tls::TLSOPT_NONE
)
1478 // Create a GOT entry for the module index.
1479 target
->got_mod_index_entry(symtab
, layout
, object
);
1481 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1482 unsupported_reloc_global(object
, r_type
, gsym
);
1485 case elfcpp::R_X86_64_DTPOFF32
:
1486 case elfcpp::R_X86_64_DTPOFF64
:
1489 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
1490 layout
->set_has_static_tls();
1491 if (optimized_type
== tls::TLSOPT_NONE
)
1493 // Create a GOT entry for the tp-relative offset.
1494 Output_data_got
<64, false>* got
1495 = target
->got_section(symtab
, layout
);
1496 got
->add_global_with_rela(gsym
, GOT_TYPE_TLS_OFFSET
,
1497 target
->rela_dyn_section(layout
),
1498 elfcpp::R_X86_64_TPOFF64
);
1500 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1501 unsupported_reloc_global(object
, r_type
, gsym
);
1504 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
1505 layout
->set_has_static_tls();
1506 if (parameters
->options().shared())
1507 unsupported_reloc_local(object
, r_type
);
1516 case elfcpp::R_X86_64_SIZE32
:
1517 case elfcpp::R_X86_64_SIZE64
:
1519 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
1520 object
->name().c_str(), r_type
,
1521 gsym
->demangled_name().c_str());
1526 // Scan relocations for a section.
1529 Target_x86_64::scan_relocs(const General_options
& options
,
1530 Symbol_table
* symtab
,
1532 Sized_relobj
<64, false>* object
,
1533 unsigned int data_shndx
,
1534 unsigned int sh_type
,
1535 const unsigned char* prelocs
,
1537 Output_section
* output_section
,
1538 bool needs_special_offset_handling
,
1539 size_t local_symbol_count
,
1540 const unsigned char* plocal_symbols
)
1542 if (sh_type
== elfcpp::SHT_REL
)
1544 gold_error(_("%s: unsupported REL reloc section"),
1545 object
->name().c_str());
1549 gold::scan_relocs
<64, false, Target_x86_64
, elfcpp::SHT_RELA
,
1550 Target_x86_64::Scan
>(
1560 needs_special_offset_handling
,
1565 // Finalize the sections.
1568 Target_x86_64::do_finalize_sections(Layout
* layout
)
1570 // Fill in some more dynamic tags.
1571 Output_data_dynamic
* const odyn
= layout
->dynamic_data();
1574 if (this->got_plt_
!= NULL
)
1575 odyn
->add_section_address(elfcpp::DT_PLTGOT
, this->got_plt_
);
1577 if (this->plt_
!= NULL
)
1579 const Output_data
* od
= this->plt_
->rel_plt();
1580 odyn
->add_section_size(elfcpp::DT_PLTRELSZ
, od
);
1581 odyn
->add_section_address(elfcpp::DT_JMPREL
, od
);
1582 odyn
->add_constant(elfcpp::DT_PLTREL
, elfcpp::DT_RELA
);
1583 if (this->plt_
->has_tlsdesc_entry())
1585 unsigned int plt_offset
= this->plt_
->get_tlsdesc_plt_offset();
1586 unsigned int got_offset
= this->plt_
->get_tlsdesc_got_offset();
1587 this->got_
->finalize_data_size();
1588 odyn
->add_section_plus_offset(elfcpp::DT_TLSDESC_PLT
,
1589 this->plt_
, plt_offset
);
1590 odyn
->add_section_plus_offset(elfcpp::DT_TLSDESC_GOT
,
1591 this->got_
, got_offset
);
1595 if (this->rela_dyn_
!= NULL
)
1597 const Output_data
* od
= this->rela_dyn_
;
1598 odyn
->add_section_address(elfcpp::DT_RELA
, od
);
1599 odyn
->add_section_size(elfcpp::DT_RELASZ
, od
);
1600 odyn
->add_constant(elfcpp::DT_RELAENT
,
1601 elfcpp::Elf_sizes
<64>::rela_size
);
1604 if (!parameters
->options().shared())
1606 // The value of the DT_DEBUG tag is filled in by the dynamic
1607 // linker at run time, and used by the debugger.
1608 odyn
->add_constant(elfcpp::DT_DEBUG
, 0);
1612 // Emit any relocs we saved in an attempt to avoid generating COPY
1614 if (this->copy_relocs_
.any_saved_relocs())
1615 this->copy_relocs_
.emit(this->rela_dyn_section(layout
));
1618 // Perform a relocation.
1621 Target_x86_64::Relocate::relocate(const Relocate_info
<64, false>* relinfo
,
1622 Target_x86_64
* target
,
1624 const elfcpp::Rela
<64, false>& rela
,
1625 unsigned int r_type
,
1626 const Sized_symbol
<64>* gsym
,
1627 const Symbol_value
<64>* psymval
,
1628 unsigned char* view
,
1629 elfcpp::Elf_types
<64>::Elf_Addr address
,
1630 section_size_type view_size
)
1632 if (this->skip_call_tls_get_addr_
)
1634 if (r_type
!= elfcpp::R_X86_64_PLT32
1636 || strcmp(gsym
->name(), "__tls_get_addr") != 0)
1638 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
1639 _("missing expected TLS relocation"));
1643 this->skip_call_tls_get_addr_
= false;
1648 // Pick the value to use for symbols defined in shared objects.
1649 Symbol_value
<64> symval
;
1651 && (gsym
->is_from_dynobj()
1652 || (parameters
->options().shared()
1653 && (gsym
->is_undefined() || gsym
->is_preemptible())))
1654 && gsym
->has_plt_offset())
1656 symval
.set_output_value(target
->plt_section()->address()
1657 + gsym
->plt_offset());
1661 const Sized_relobj
<64, false>* object
= relinfo
->object
;
1662 const elfcpp::Elf_Xword addend
= rela
.get_r_addend();
1664 // Get the GOT offset if needed.
1665 // The GOT pointer points to the end of the GOT section.
1666 // We need to subtract the size of the GOT section to get
1667 // the actual offset to use in the relocation.
1668 bool have_got_offset
= false;
1669 unsigned int got_offset
= 0;
1672 case elfcpp::R_X86_64_GOT32
:
1673 case elfcpp::R_X86_64_GOT64
:
1674 case elfcpp::R_X86_64_GOTPLT64
:
1675 case elfcpp::R_X86_64_GOTPCREL
:
1676 case elfcpp::R_X86_64_GOTPCREL64
:
1679 gold_assert(gsym
->has_got_offset(GOT_TYPE_STANDARD
));
1680 got_offset
= gsym
->got_offset(GOT_TYPE_STANDARD
) - target
->got_size();
1684 unsigned int r_sym
= elfcpp::elf_r_sym
<64>(rela
.get_r_info());
1685 gold_assert(object
->local_has_got_offset(r_sym
, GOT_TYPE_STANDARD
));
1686 got_offset
= (object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
)
1687 - target
->got_size());
1689 have_got_offset
= true;
1698 case elfcpp::R_X86_64_NONE
:
1699 case elfcpp::R_386_GNU_VTINHERIT
:
1700 case elfcpp::R_386_GNU_VTENTRY
:
1703 case elfcpp::R_X86_64_64
:
1704 Relocate_functions
<64, false>::rela64(view
, object
, psymval
, addend
);
1707 case elfcpp::R_X86_64_PC64
:
1708 Relocate_functions
<64, false>::pcrela64(view
, object
, psymval
, addend
,
1712 case elfcpp::R_X86_64_32
:
1713 // FIXME: we need to verify that value + addend fits into 32 bits:
1714 // uint64_t x = value + addend;
1715 // x == static_cast<uint64_t>(static_cast<uint32_t>(x))
1716 // Likewise for other <=32-bit relocations (but see R_X86_64_32S).
1717 Relocate_functions
<64, false>::rela32(view
, object
, psymval
, addend
);
1720 case elfcpp::R_X86_64_32S
:
1721 // FIXME: we need to verify that value + addend fits into 32 bits:
1722 // int64_t x = value + addend; // note this quantity is signed!
1723 // x == static_cast<int64_t>(static_cast<int32_t>(x))
1724 Relocate_functions
<64, false>::rela32(view
, object
, psymval
, addend
);
1727 case elfcpp::R_X86_64_PC32
:
1728 Relocate_functions
<64, false>::pcrela32(view
, object
, psymval
, addend
,
1732 case elfcpp::R_X86_64_16
:
1733 Relocate_functions
<64, false>::rela16(view
, object
, psymval
, addend
);
1736 case elfcpp::R_X86_64_PC16
:
1737 Relocate_functions
<64, false>::pcrela16(view
, object
, psymval
, addend
,
1741 case elfcpp::R_X86_64_8
:
1742 Relocate_functions
<64, false>::rela8(view
, object
, psymval
, addend
);
1745 case elfcpp::R_X86_64_PC8
:
1746 Relocate_functions
<64, false>::pcrela8(view
, object
, psymval
, addend
,
1750 case elfcpp::R_X86_64_PLT32
:
1751 gold_assert(gsym
== NULL
1752 || gsym
->has_plt_offset()
1753 || gsym
->final_value_is_known()
1754 || (gsym
->is_defined()
1755 && !gsym
->is_from_dynobj()
1756 && !gsym
->is_preemptible()));
1757 // Note: while this code looks the same as for R_X86_64_PC32, it
1758 // behaves differently because psymval was set to point to
1759 // the PLT entry, rather than the symbol, in Scan::global().
1760 Relocate_functions
<64, false>::pcrela32(view
, object
, psymval
, addend
,
1764 case elfcpp::R_X86_64_PLTOFF64
:
1767 gold_assert(gsym
->has_plt_offset()
1768 || gsym
->final_value_is_known());
1769 elfcpp::Elf_types
<64>::Elf_Addr got_address
;
1770 got_address
= target
->got_section(NULL
, NULL
)->address();
1771 Relocate_functions
<64, false>::rela64(view
, object
, psymval
,
1772 addend
- got_address
);
1775 case elfcpp::R_X86_64_GOT32
:
1776 gold_assert(have_got_offset
);
1777 Relocate_functions
<64, false>::rela32(view
, got_offset
, addend
);
1780 case elfcpp::R_X86_64_GOTPC32
:
1783 elfcpp::Elf_types
<64>::Elf_Addr value
;
1784 value
= target
->got_plt_section()->address();
1785 Relocate_functions
<64, false>::pcrela32(view
, value
, addend
, address
);
1789 case elfcpp::R_X86_64_GOT64
:
1790 // The ABI doc says "Like GOT64, but indicates a PLT entry is needed."
1791 // Since we always add a PLT entry, this is equivalent.
1792 case elfcpp::R_X86_64_GOTPLT64
:
1793 gold_assert(have_got_offset
);
1794 Relocate_functions
<64, false>::rela64(view
, got_offset
, addend
);
1797 case elfcpp::R_X86_64_GOTPC64
:
1800 elfcpp::Elf_types
<64>::Elf_Addr value
;
1801 value
= target
->got_plt_section()->address();
1802 Relocate_functions
<64, false>::pcrela64(view
, value
, addend
, address
);
1806 case elfcpp::R_X86_64_GOTOFF64
:
1808 elfcpp::Elf_types
<64>::Elf_Addr value
;
1809 value
= (psymval
->value(object
, 0)
1810 - target
->got_plt_section()->address());
1811 Relocate_functions
<64, false>::rela64(view
, value
, addend
);
1815 case elfcpp::R_X86_64_GOTPCREL
:
1817 gold_assert(have_got_offset
);
1818 elfcpp::Elf_types
<64>::Elf_Addr value
;
1819 value
= target
->got_plt_section()->address() + got_offset
;
1820 Relocate_functions
<64, false>::pcrela32(view
, value
, addend
, address
);
1824 case elfcpp::R_X86_64_GOTPCREL64
:
1826 gold_assert(have_got_offset
);
1827 elfcpp::Elf_types
<64>::Elf_Addr value
;
1828 value
= target
->got_plt_section()->address() + got_offset
;
1829 Relocate_functions
<64, false>::pcrela64(view
, value
, addend
, address
);
1833 case elfcpp::R_X86_64_COPY
:
1834 case elfcpp::R_X86_64_GLOB_DAT
:
1835 case elfcpp::R_X86_64_JUMP_SLOT
:
1836 case elfcpp::R_X86_64_RELATIVE
:
1837 // These are outstanding tls relocs, which are unexpected when linking
1838 case elfcpp::R_X86_64_TPOFF64
:
1839 case elfcpp::R_X86_64_DTPMOD64
:
1840 case elfcpp::R_X86_64_TLSDESC
:
1841 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
1842 _("unexpected reloc %u in object file"),
1846 // These are initial tls relocs, which are expected when linking
1847 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
1848 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
1849 case elfcpp::R_X86_64_TLSDESC_CALL
:
1850 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
1851 case elfcpp::R_X86_64_DTPOFF32
:
1852 case elfcpp::R_X86_64_DTPOFF64
:
1853 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
1854 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
1855 this->relocate_tls(relinfo
, target
, relnum
, rela
, r_type
, gsym
, psymval
,
1856 view
, address
, view_size
);
1859 case elfcpp::R_X86_64_SIZE32
:
1860 case elfcpp::R_X86_64_SIZE64
:
1862 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
1863 _("unsupported reloc %u"),
1871 // Perform a TLS relocation.
1874 Target_x86_64::Relocate::relocate_tls(const Relocate_info
<64, false>* relinfo
,
1875 Target_x86_64
* target
,
1877 const elfcpp::Rela
<64, false>& rela
,
1878 unsigned int r_type
,
1879 const Sized_symbol
<64>* gsym
,
1880 const Symbol_value
<64>* psymval
,
1881 unsigned char* view
,
1882 elfcpp::Elf_types
<64>::Elf_Addr address
,
1883 section_size_type view_size
)
1885 Output_segment
* tls_segment
= relinfo
->layout
->tls_segment();
1887 const Sized_relobj
<64, false>* object
= relinfo
->object
;
1888 const elfcpp::Elf_Xword addend
= rela
.get_r_addend();
1890 elfcpp::Elf_types
<64>::Elf_Addr value
= psymval
->value(relinfo
->object
, 0);
1892 const bool is_final
= (gsym
== NULL
1893 ? !parameters
->options().output_is_position_independent()
1894 : gsym
->final_value_is_known());
1895 const tls::Tls_optimization optimized_type
1896 = Target_x86_64::optimize_tls_reloc(is_final
, r_type
);
1899 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
1900 if (optimized_type
== tls::TLSOPT_TO_LE
)
1902 gold_assert(tls_segment
!= NULL
);
1903 this->tls_gd_to_le(relinfo
, relnum
, tls_segment
,
1904 rela
, r_type
, value
, view
,
1910 unsigned int got_type
= (optimized_type
== tls::TLSOPT_TO_IE
1911 ? GOT_TYPE_TLS_OFFSET
1912 : GOT_TYPE_TLS_PAIR
);
1913 unsigned int got_offset
;
1916 gold_assert(gsym
->has_got_offset(got_type
));
1917 got_offset
= gsym
->got_offset(got_type
) - target
->got_size();
1921 unsigned int r_sym
= elfcpp::elf_r_sym
<64>(rela
.get_r_info());
1922 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
1923 got_offset
= (object
->local_got_offset(r_sym
, got_type
)
1924 - target
->got_size());
1926 if (optimized_type
== tls::TLSOPT_TO_IE
)
1928 gold_assert(tls_segment
!= NULL
);
1929 value
= target
->got_plt_section()->address() + got_offset
;
1930 this->tls_gd_to_ie(relinfo
, relnum
, tls_segment
, rela
, r_type
,
1931 value
, view
, address
, view_size
);
1934 else if (optimized_type
== tls::TLSOPT_NONE
)
1936 // Relocate the field with the offset of the pair of GOT
1938 value
= target
->got_plt_section()->address() + got_offset
;
1939 Relocate_functions
<64, false>::pcrela32(view
, value
, addend
,
1944 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
1945 _("unsupported reloc %u"), r_type
);
1948 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
1949 case elfcpp::R_X86_64_TLSDESC_CALL
:
1950 if (optimized_type
== tls::TLSOPT_TO_LE
)
1952 gold_assert(tls_segment
!= NULL
);
1953 this->tls_desc_gd_to_le(relinfo
, relnum
, tls_segment
,
1954 rela
, r_type
, value
, view
,
1960 unsigned int got_type
= (optimized_type
== tls::TLSOPT_TO_IE
1961 ? GOT_TYPE_TLS_OFFSET
1962 : GOT_TYPE_TLS_DESC
);
1963 unsigned int got_offset
;
1966 gold_assert(gsym
->has_got_offset(got_type
));
1967 got_offset
= gsym
->got_offset(got_type
) - target
->got_size();
1971 unsigned int r_sym
= elfcpp::elf_r_sym
<64>(rela
.get_r_info());
1972 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
1973 got_offset
= (object
->local_got_offset(r_sym
, got_type
)
1974 - target
->got_size());
1976 if (optimized_type
== tls::TLSOPT_TO_IE
)
1978 gold_assert(tls_segment
!= NULL
);
1979 value
= target
->got_plt_section()->address() + got_offset
;
1980 this->tls_desc_gd_to_ie(relinfo
, relnum
, tls_segment
,
1981 rela
, r_type
, value
, view
, address
,
1985 else if (optimized_type
== tls::TLSOPT_NONE
)
1987 if (r_type
== elfcpp::R_X86_64_GOTPC32_TLSDESC
)
1989 // Relocate the field with the offset of the pair of GOT
1991 value
= target
->got_plt_section()->address() + got_offset
;
1992 Relocate_functions
<64, false>::pcrela32(view
, value
, addend
,
1998 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
1999 _("unsupported reloc %u"), r_type
);
2002 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
2003 if (optimized_type
== tls::TLSOPT_TO_LE
)
2005 gold_assert(tls_segment
!= NULL
);
2006 this->tls_ld_to_le(relinfo
, relnum
, tls_segment
, rela
, r_type
,
2007 value
, view
, view_size
);
2010 else if (optimized_type
== tls::TLSOPT_NONE
)
2012 // Relocate the field with the offset of the GOT entry for
2013 // the module index.
2014 unsigned int got_offset
;
2015 got_offset
= (target
->got_mod_index_entry(NULL
, NULL
, NULL
)
2016 - target
->got_size());
2017 value
= target
->got_plt_section()->address() + got_offset
;
2018 Relocate_functions
<64, false>::pcrela32(view
, value
, addend
,
2022 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
2023 _("unsupported reloc %u"), r_type
);
2026 case elfcpp::R_X86_64_DTPOFF32
:
2027 gold_assert(tls_segment
!= NULL
);
2028 if (optimized_type
== tls::TLSOPT_TO_LE
)
2029 value
-= tls_segment
->memsz();
2030 Relocate_functions
<64, false>::rela32(view
, value
, 0);
2033 case elfcpp::R_X86_64_DTPOFF64
:
2034 gold_assert(tls_segment
!= NULL
);
2035 if (optimized_type
== tls::TLSOPT_TO_LE
)
2036 value
-= tls_segment
->memsz();
2037 Relocate_functions
<64, false>::rela64(view
, value
, 0);
2040 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
2041 if (optimized_type
== tls::TLSOPT_TO_LE
)
2043 gold_assert(tls_segment
!= NULL
);
2044 Target_x86_64::Relocate::tls_ie_to_le(relinfo
, relnum
, tls_segment
,
2045 rela
, r_type
, value
, view
,
2049 else if (optimized_type
== tls::TLSOPT_NONE
)
2051 // Relocate the field with the offset of the GOT entry for
2052 // the tp-relative offset of the symbol.
2053 unsigned int got_offset
;
2056 gold_assert(gsym
->has_got_offset(GOT_TYPE_TLS_OFFSET
));
2057 got_offset
= (gsym
->got_offset(GOT_TYPE_TLS_OFFSET
)
2058 - target
->got_size());
2062 unsigned int r_sym
= elfcpp::elf_r_sym
<64>(rela
.get_r_info());
2063 gold_assert(object
->local_has_got_offset(r_sym
,
2064 GOT_TYPE_TLS_OFFSET
));
2065 got_offset
= (object
->local_got_offset(r_sym
, GOT_TYPE_TLS_OFFSET
)
2066 - target
->got_size());
2068 value
= target
->got_plt_section()->address() + got_offset
;
2069 Relocate_functions
<64, false>::pcrela32(view
, value
, addend
, address
);
2072 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
2073 _("unsupported reloc type %u"),
2077 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
2078 value
-= tls_segment
->memsz();
2079 Relocate_functions
<64, false>::rela32(view
, value
, 0);
2084 // Do a relocation in which we convert a TLS General-Dynamic to an
2088 Target_x86_64::Relocate::tls_gd_to_ie(const Relocate_info
<64, false>* relinfo
,
2091 const elfcpp::Rela
<64, false>& rela
,
2093 elfcpp::Elf_types
<64>::Elf_Addr value
,
2094 unsigned char* view
,
2095 elfcpp::Elf_types
<64>::Elf_Addr address
,
2096 section_size_type view_size
)
2098 // .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
2099 // .word 0x6666; rex64; call __tls_get_addr
2100 // ==> movq %fs:0,%rax; addq x@gottpoff(%rip),%rax
2102 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -4);
2103 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 12);
2105 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
2106 (memcmp(view
- 4, "\x66\x48\x8d\x3d", 4) == 0));
2107 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
2108 (memcmp(view
+ 4, "\x66\x66\x48\xe8", 4) == 0));
2110 memcpy(view
- 4, "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x03\x05\0\0\0\0", 16);
2112 const elfcpp::Elf_Xword addend
= rela
.get_r_addend();
2113 Relocate_functions
<64, false>::pcrela32(view
+ 8, value
, addend
- 8, address
);
2115 // The next reloc should be a PLT32 reloc against __tls_get_addr.
2117 this->skip_call_tls_get_addr_
= true;
2120 // Do a relocation in which we convert a TLS General-Dynamic to a
2124 Target_x86_64::Relocate::tls_gd_to_le(const Relocate_info
<64, false>* relinfo
,
2126 Output_segment
* tls_segment
,
2127 const elfcpp::Rela
<64, false>& rela
,
2129 elfcpp::Elf_types
<64>::Elf_Addr value
,
2130 unsigned char* view
,
2131 section_size_type view_size
)
2133 // .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
2134 // .word 0x6666; rex64; call __tls_get_addr
2135 // ==> movq %fs:0,%rax; leaq x@tpoff(%rax),%rax
2137 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -4);
2138 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 12);
2140 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
2141 (memcmp(view
- 4, "\x66\x48\x8d\x3d", 4) == 0));
2142 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
2143 (memcmp(view
+ 4, "\x66\x66\x48\xe8", 4) == 0));
2145 memcpy(view
- 4, "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0\0", 16);
2147 value
-= tls_segment
->memsz();
2148 Relocate_functions
<64, false>::rela32(view
+ 8, value
, 0);
2150 // The next reloc should be a PLT32 reloc against __tls_get_addr.
2152 this->skip_call_tls_get_addr_
= true;
2155 // Do a TLSDESC-style General-Dynamic to Initial-Exec transition.
2158 Target_x86_64::Relocate::tls_desc_gd_to_ie(
2159 const Relocate_info
<64, false>* relinfo
,
2162 const elfcpp::Rela
<64, false>& rela
,
2163 unsigned int r_type
,
2164 elfcpp::Elf_types
<64>::Elf_Addr value
,
2165 unsigned char* view
,
2166 elfcpp::Elf_types
<64>::Elf_Addr address
,
2167 section_size_type view_size
)
2169 if (r_type
== elfcpp::R_X86_64_GOTPC32_TLSDESC
)
2171 // leaq foo@tlsdesc(%rip), %rax
2172 // ==> movq foo@gottpoff(%rip), %rax
2173 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -3);
2174 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 4);
2175 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
2176 view
[-3] == 0x48 && view
[-2] == 0x8d && view
[-1] == 0x05);
2178 const elfcpp::Elf_Xword addend
= rela
.get_r_addend();
2179 Relocate_functions
<64, false>::pcrela32(view
, value
, addend
, address
);
2183 // call *foo@tlscall(%rax)
2185 gold_assert(r_type
== elfcpp::R_X86_64_TLSDESC_CALL
);
2186 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 2);
2187 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
2188 view
[0] == 0xff && view
[1] == 0x10);
2194 // Do a TLSDESC-style General-Dynamic to Local-Exec transition.
2197 Target_x86_64::Relocate::tls_desc_gd_to_le(
2198 const Relocate_info
<64, false>* relinfo
,
2200 Output_segment
* tls_segment
,
2201 const elfcpp::Rela
<64, false>& rela
,
2202 unsigned int r_type
,
2203 elfcpp::Elf_types
<64>::Elf_Addr value
,
2204 unsigned char* view
,
2205 section_size_type view_size
)
2207 if (r_type
== elfcpp::R_X86_64_GOTPC32_TLSDESC
)
2209 // leaq foo@tlsdesc(%rip), %rax
2210 // ==> movq foo@tpoff, %rax
2211 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -3);
2212 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 4);
2213 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
2214 view
[-3] == 0x48 && view
[-2] == 0x8d && view
[-1] == 0x05);
2217 value
-= tls_segment
->memsz();
2218 Relocate_functions
<64, false>::rela32(view
, value
, 0);
2222 // call *foo@tlscall(%rax)
2224 gold_assert(r_type
== elfcpp::R_X86_64_TLSDESC_CALL
);
2225 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 2);
2226 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
2227 view
[0] == 0xff && view
[1] == 0x10);
2234 Target_x86_64::Relocate::tls_ld_to_le(const Relocate_info
<64, false>* relinfo
,
2237 const elfcpp::Rela
<64, false>& rela
,
2239 elfcpp::Elf_types
<64>::Elf_Addr
,
2240 unsigned char* view
,
2241 section_size_type view_size
)
2243 // leaq foo@tlsld(%rip),%rdi; call __tls_get_addr@plt;
2244 // ... leq foo@dtpoff(%rax),%reg
2245 // ==> .word 0x6666; .byte 0x66; movq %fs:0,%rax ... leaq x@tpoff(%rax),%rdx
2247 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -3);
2248 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 9);
2250 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
2251 view
[-3] == 0x48 && view
[-2] == 0x8d && view
[-1] == 0x3d);
2253 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(), view
[4] == 0xe8);
2255 memcpy(view
- 3, "\x66\x66\x66\x64\x48\x8b\x04\x25\0\0\0\0", 12);
2257 // The next reloc should be a PLT32 reloc against __tls_get_addr.
2259 this->skip_call_tls_get_addr_
= true;
2262 // Do a relocation in which we convert a TLS Initial-Exec to a
2266 Target_x86_64::Relocate::tls_ie_to_le(const Relocate_info
<64, false>* relinfo
,
2268 Output_segment
* tls_segment
,
2269 const elfcpp::Rela
<64, false>& rela
,
2271 elfcpp::Elf_types
<64>::Elf_Addr value
,
2272 unsigned char* view
,
2273 section_size_type view_size
)
2275 // We need to examine the opcodes to figure out which instruction we
2278 // movq foo@gottpoff(%rip),%reg ==> movq $YY,%reg
2279 // addq foo@gottpoff(%rip),%reg ==> addq $YY,%reg
2281 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -3);
2282 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 4);
2284 unsigned char op1
= view
[-3];
2285 unsigned char op2
= view
[-2];
2286 unsigned char op3
= view
[-1];
2287 unsigned char reg
= op3
>> 3;
2295 view
[-1] = 0xc0 | reg
;
2299 // Special handling for %rsp.
2303 view
[-1] = 0xc0 | reg
;
2311 view
[-1] = 0x80 | reg
| (reg
<< 3);
2314 value
-= tls_segment
->memsz();
2315 Relocate_functions
<64, false>::rela32(view
, value
, 0);
2318 // Relocate section data.
2321 Target_x86_64::relocate_section(const Relocate_info
<64, false>* relinfo
,
2322 unsigned int sh_type
,
2323 const unsigned char* prelocs
,
2325 Output_section
* output_section
,
2326 bool needs_special_offset_handling
,
2327 unsigned char* view
,
2328 elfcpp::Elf_types
<64>::Elf_Addr address
,
2329 section_size_type view_size
)
2331 gold_assert(sh_type
== elfcpp::SHT_RELA
);
2333 gold::relocate_section
<64, false, Target_x86_64
, elfcpp::SHT_RELA
,
2334 Target_x86_64::Relocate
>(
2340 needs_special_offset_handling
,
2346 // Return the size of a relocation while scanning during a relocatable
2350 Target_x86_64::Relocatable_size_for_reloc::get_size_for_reloc(
2351 unsigned int r_type
,
2356 case elfcpp::R_X86_64_NONE
:
2357 case elfcpp::R_386_GNU_VTINHERIT
:
2358 case elfcpp::R_386_GNU_VTENTRY
:
2359 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
2360 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
2361 case elfcpp::R_X86_64_TLSDESC_CALL
:
2362 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
2363 case elfcpp::R_X86_64_DTPOFF32
:
2364 case elfcpp::R_X86_64_DTPOFF64
:
2365 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
2366 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
2369 case elfcpp::R_X86_64_64
:
2370 case elfcpp::R_X86_64_PC64
:
2371 case elfcpp::R_X86_64_GOTOFF64
:
2372 case elfcpp::R_X86_64_GOTPC64
:
2373 case elfcpp::R_X86_64_PLTOFF64
:
2374 case elfcpp::R_X86_64_GOT64
:
2375 case elfcpp::R_X86_64_GOTPCREL64
:
2376 case elfcpp::R_X86_64_GOTPCREL
:
2377 case elfcpp::R_X86_64_GOTPLT64
:
2380 case elfcpp::R_X86_64_32
:
2381 case elfcpp::R_X86_64_32S
:
2382 case elfcpp::R_X86_64_PC32
:
2383 case elfcpp::R_X86_64_PLT32
:
2384 case elfcpp::R_X86_64_GOTPC32
:
2385 case elfcpp::R_X86_64_GOT32
:
2388 case elfcpp::R_X86_64_16
:
2389 case elfcpp::R_X86_64_PC16
:
2392 case elfcpp::R_X86_64_8
:
2393 case elfcpp::R_X86_64_PC8
:
2396 case elfcpp::R_X86_64_COPY
:
2397 case elfcpp::R_X86_64_GLOB_DAT
:
2398 case elfcpp::R_X86_64_JUMP_SLOT
:
2399 case elfcpp::R_X86_64_RELATIVE
:
2400 // These are outstanding tls relocs, which are unexpected when linking
2401 case elfcpp::R_X86_64_TPOFF64
:
2402 case elfcpp::R_X86_64_DTPMOD64
:
2403 case elfcpp::R_X86_64_TLSDESC
:
2404 object
->error(_("unexpected reloc %u in object file"), r_type
);
2407 case elfcpp::R_X86_64_SIZE32
:
2408 case elfcpp::R_X86_64_SIZE64
:
2410 object
->error(_("unsupported reloc %u against local symbol"), r_type
);
2415 // Scan the relocs during a relocatable link.
2418 Target_x86_64::scan_relocatable_relocs(const General_options
& options
,
2419 Symbol_table
* symtab
,
2421 Sized_relobj
<64, false>* object
,
2422 unsigned int data_shndx
,
2423 unsigned int sh_type
,
2424 const unsigned char* prelocs
,
2426 Output_section
* output_section
,
2427 bool needs_special_offset_handling
,
2428 size_t local_symbol_count
,
2429 const unsigned char* plocal_symbols
,
2430 Relocatable_relocs
* rr
)
2432 gold_assert(sh_type
== elfcpp::SHT_RELA
);
2434 typedef gold::Default_scan_relocatable_relocs
<elfcpp::SHT_RELA
,
2435 Relocatable_size_for_reloc
> Scan_relocatable_relocs
;
2437 gold::scan_relocatable_relocs
<64, false, elfcpp::SHT_RELA
,
2438 Scan_relocatable_relocs
>(
2447 needs_special_offset_handling
,
2453 // Relocate a section during a relocatable link.
2456 Target_x86_64::relocate_for_relocatable(
2457 const Relocate_info
<64, false>* relinfo
,
2458 unsigned int sh_type
,
2459 const unsigned char* prelocs
,
2461 Output_section
* output_section
,
2462 off_t offset_in_output_section
,
2463 const Relocatable_relocs
* rr
,
2464 unsigned char* view
,
2465 elfcpp::Elf_types
<64>::Elf_Addr view_address
,
2466 section_size_type view_size
,
2467 unsigned char* reloc_view
,
2468 section_size_type reloc_view_size
)
2470 gold_assert(sh_type
== elfcpp::SHT_RELA
);
2472 gold::relocate_for_relocatable
<64, false, elfcpp::SHT_RELA
>(
2477 offset_in_output_section
,
2486 // Return the value to use for a dynamic which requires special
2487 // treatment. This is how we support equality comparisons of function
2488 // pointers across shared library boundaries, as described in the
2489 // processor specific ABI supplement.
2492 Target_x86_64::do_dynsym_value(const Symbol
* gsym
) const
2494 gold_assert(gsym
->is_from_dynobj() && gsym
->has_plt_offset());
2495 return this->plt_section()->address() + gsym
->plt_offset();
2498 // Return a string used to fill a code section with nops to take up
2499 // the specified length.
2502 Target_x86_64::do_code_fill(section_size_type length
) const
2506 // Build a jmpq instruction to skip over the bytes.
2507 unsigned char jmp
[5];
2509 elfcpp::Swap_unaligned
<32, false>::writeval(jmp
+ 1, length
- 5);
2510 return (std::string(reinterpret_cast<char*>(&jmp
[0]), 5)
2511 + std::string(length
- 5, '\0'));
2514 // Nop sequences of various lengths.
2515 const char nop1
[1] = { 0x90 }; // nop
2516 const char nop2
[2] = { 0x66, 0x90 }; // xchg %ax %ax
2517 const char nop3
[3] = { 0x8d, 0x76, 0x00 }; // leal 0(%esi),%esi
2518 const char nop4
[4] = { 0x8d, 0x74, 0x26, 0x00}; // leal 0(%esi,1),%esi
2519 const char nop5
[5] = { 0x90, 0x8d, 0x74, 0x26, // nop
2520 0x00 }; // leal 0(%esi,1),%esi
2521 const char nop6
[6] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2523 const char nop7
[7] = { 0x8d, 0xb4, 0x26, 0x00, // leal 0L(%esi,1),%esi
2525 const char nop8
[8] = { 0x90, 0x8d, 0xb4, 0x26, // nop
2526 0x00, 0x00, 0x00, 0x00 }; // leal 0L(%esi,1),%esi
2527 const char nop9
[9] = { 0x89, 0xf6, 0x8d, 0xbc, // movl %esi,%esi
2528 0x27, 0x00, 0x00, 0x00, // leal 0L(%edi,1),%edi
2530 const char nop10
[10] = { 0x8d, 0x76, 0x00, 0x8d, // leal 0(%esi),%esi
2531 0xbc, 0x27, 0x00, 0x00, // leal 0L(%edi,1),%edi
2533 const char nop11
[11] = { 0x8d, 0x74, 0x26, 0x00, // leal 0(%esi,1),%esi
2534 0x8d, 0xbc, 0x27, 0x00, // leal 0L(%edi,1),%edi
2536 const char nop12
[12] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2537 0x00, 0x00, 0x8d, 0xbf, // leal 0L(%edi),%edi
2538 0x00, 0x00, 0x00, 0x00 };
2539 const char nop13
[13] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2540 0x00, 0x00, 0x8d, 0xbc, // leal 0L(%edi,1),%edi
2541 0x27, 0x00, 0x00, 0x00,
2543 const char nop14
[14] = { 0x8d, 0xb4, 0x26, 0x00, // leal 0L(%esi,1),%esi
2544 0x00, 0x00, 0x00, 0x8d, // leal 0L(%edi,1),%edi
2545 0xbc, 0x27, 0x00, 0x00,
2547 const char nop15
[15] = { 0xeb, 0x0d, 0x90, 0x90, // jmp .+15
2548 0x90, 0x90, 0x90, 0x90, // nop,nop,nop,...
2549 0x90, 0x90, 0x90, 0x90,
2552 const char* nops
[16] = {
2554 nop1
, nop2
, nop3
, nop4
, nop5
, nop6
, nop7
,
2555 nop8
, nop9
, nop10
, nop11
, nop12
, nop13
, nop14
, nop15
2558 return std::string(nops
[length
], length
);
2561 // The selector for x86_64 object files.
2563 class Target_selector_x86_64
: public Target_selector
2566 Target_selector_x86_64()
2567 : Target_selector(elfcpp::EM_X86_64
, 64, false, "elf64-x86-64")
2571 do_instantiate_target()
2572 { return new Target_x86_64(); }
2575 Target_selector_x86_64 target_selector_x86_64
;
2577 } // End anonymous namespace.