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), saw_tls_block_reloc_(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_
;
292 // This is set if we see a relocation which could load the address
293 // of the TLS block. Whether we see such a relocation determines
294 // how we handle the R_X86_64_DTPOFF32 relocation, which is used
295 // in debugging sections.
296 bool saw_tls_block_reloc_
;
299 // A class which returns the size required for a relocation type,
300 // used while scanning relocs during a relocatable link.
301 class Relocatable_size_for_reloc
305 get_size_for_reloc(unsigned int, Relobj
*);
308 // Adjust TLS relocation type based on the options and whether this
309 // is a local symbol.
310 static tls::Tls_optimization
311 optimize_tls_reloc(bool is_final
, int r_type
);
313 // Get the GOT section, creating it if necessary.
314 Output_data_got
<64, false>*
315 got_section(Symbol_table
*, Layout
*);
317 // Get the GOT PLT section.
319 got_plt_section() const
321 gold_assert(this->got_plt_
!= NULL
);
322 return this->got_plt_
;
325 // Create the PLT section.
327 make_plt_section(Symbol_table
* symtab
, Layout
* layout
);
329 // Create a PLT entry for a global symbol.
331 make_plt_entry(Symbol_table
*, Layout
*, Symbol
*);
333 // Define the _TLS_MODULE_BASE_ symbol at the end of the TLS segment.
335 define_tls_base_symbol(Symbol_table
*, Layout
*);
337 // Create the reserved PLT and GOT entries for the TLS descriptor resolver.
339 reserve_tlsdesc_entries(Symbol_table
* symtab
, Layout
* layout
);
341 // Create a GOT entry for the TLS module index.
343 got_mod_index_entry(Symbol_table
* symtab
, Layout
* layout
,
344 Sized_relobj
<64, false>* object
);
346 // Get the PLT section.
347 Output_data_plt_x86_64
*
350 gold_assert(this->plt_
!= NULL
);
354 // Get the dynamic reloc section, creating it if necessary.
356 rela_dyn_section(Layout
*);
358 // Return true if the symbol may need a COPY relocation.
359 // References from an executable object to non-function symbols
360 // defined in a dynamic object may need a COPY relocation.
362 may_need_copy_reloc(Symbol
* gsym
)
364 return (!parameters
->options().shared()
365 && gsym
->is_from_dynobj()
366 && gsym
->type() != elfcpp::STT_FUNC
);
369 // Add a potential copy relocation.
371 copy_reloc(Symbol_table
* symtab
, Layout
* layout
, Relobj
* object
,
372 unsigned int shndx
, Output_section
* output_section
,
373 Symbol
* sym
, const elfcpp::Rela
<64, false>& reloc
)
375 this->copy_relocs_
.copy_reloc(symtab
, layout
,
376 symtab
->get_sized_symbol
<64>(sym
),
377 object
, shndx
, output_section
,
378 reloc
, this->rela_dyn_section(layout
));
381 // Information about this specific target which we pass to the
382 // general Target structure.
383 static const Target::Target_info x86_64_info
;
387 GOT_TYPE_STANDARD
= 0, // GOT entry for a regular symbol
388 GOT_TYPE_TLS_OFFSET
= 1, // GOT entry for TLS offset
389 GOT_TYPE_TLS_PAIR
= 2, // GOT entry for TLS module/offset pair
390 GOT_TYPE_TLS_DESC
= 3 // GOT entry for TLS_DESC pair
394 Output_data_got
<64, false>* got_
;
396 Output_data_plt_x86_64
* plt_
;
397 // The GOT PLT section.
398 Output_data_space
* got_plt_
;
399 // The dynamic reloc section.
400 Reloc_section
* rela_dyn_
;
401 // Relocs saved to avoid a COPY reloc.
402 Copy_relocs
<elfcpp::SHT_RELA
, 64, false> copy_relocs_
;
403 // Space for variables copied with a COPY reloc.
404 Output_data_space
* dynbss_
;
405 // Offset of the GOT entry for the TLS module index.
406 unsigned int got_mod_index_offset_
;
407 // True if the _TLS_MODULE_BASE_ symbol has been defined.
408 bool tls_base_symbol_defined_
;
411 const Target::Target_info
Target_x86_64::x86_64_info
=
414 false, // is_big_endian
415 elfcpp::EM_X86_64
, // machine_code
416 false, // has_make_symbol
417 false, // has_resolve
418 true, // has_code_fill
419 true, // is_default_stack_executable
421 "/lib/ld64.so.1", // program interpreter
422 0x400000, // default_text_segment_address
423 0x1000, // abi_pagesize (overridable by -z max-page-size)
424 0x1000 // common_pagesize (overridable by -z common-page-size)
427 // Get the GOT section, creating it if necessary.
429 Output_data_got
<64, false>*
430 Target_x86_64::got_section(Symbol_table
* symtab
, Layout
* layout
)
432 if (this->got_
== NULL
)
434 gold_assert(symtab
!= NULL
&& layout
!= NULL
);
436 this->got_
= new Output_data_got
<64, false>();
438 layout
->add_output_section_data(".got", elfcpp::SHT_PROGBITS
,
439 elfcpp::SHF_ALLOC
| elfcpp::SHF_WRITE
,
442 // The old GNU linker creates a .got.plt section. We just
443 // create another set of data in the .got section. Note that we
444 // always create a PLT if we create a GOT, although the PLT
446 this->got_plt_
= new Output_data_space(8);
447 layout
->add_output_section_data(".got", elfcpp::SHT_PROGBITS
,
448 elfcpp::SHF_ALLOC
| elfcpp::SHF_WRITE
,
451 // The first three entries are reserved.
452 this->got_plt_
->set_current_data_size(3 * 8);
454 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
455 symtab
->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL
,
457 0, 0, elfcpp::STT_OBJECT
,
459 elfcpp::STV_HIDDEN
, 0,
466 // Get the dynamic reloc section, creating it if necessary.
468 Target_x86_64::Reloc_section
*
469 Target_x86_64::rela_dyn_section(Layout
* layout
)
471 if (this->rela_dyn_
== NULL
)
473 gold_assert(layout
!= NULL
);
474 this->rela_dyn_
= new Reloc_section(parameters
->options().combreloc());
475 layout
->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA
,
476 elfcpp::SHF_ALLOC
, this->rela_dyn_
);
478 return this->rela_dyn_
;
481 // A class to handle the PLT data.
483 class Output_data_plt_x86_64
: public Output_section_data
486 typedef Output_data_reloc
<elfcpp::SHT_RELA
, true, 64, false> Reloc_section
;
488 Output_data_plt_x86_64(Layout
*, Output_data_got
<64, false>*,
491 // Add an entry to the PLT.
493 add_entry(Symbol
* gsym
);
495 // Add the reserved TLSDESC_PLT entry to the PLT.
497 reserve_tlsdesc_entry(unsigned int got_offset
)
498 { this->tlsdesc_got_offset_
= got_offset
; }
500 // Return true if a TLSDESC_PLT entry has been reserved.
502 has_tlsdesc_entry() const
503 { return this->tlsdesc_got_offset_
!= -1U; }
505 // Return the GOT offset for the reserved TLSDESC_PLT entry.
507 get_tlsdesc_got_offset() const
508 { return this->tlsdesc_got_offset_
; }
510 // Return the offset of the reserved TLSDESC_PLT entry.
512 get_tlsdesc_plt_offset() const
513 { return (this->count_
+ 1) * plt_entry_size
; }
515 // Return the .rel.plt section data.
518 { return this->rel_
; }
522 do_adjust_output_section(Output_section
* os
);
525 // The size of an entry in the PLT.
526 static const int plt_entry_size
= 16;
528 // The first entry in the PLT.
529 // From the AMD64 ABI: "Unlike Intel386 ABI, this ABI uses the same
530 // procedure linkage table for both programs and shared objects."
531 static unsigned char first_plt_entry
[plt_entry_size
];
533 // Other entries in the PLT for an executable.
534 static unsigned char plt_entry
[plt_entry_size
];
536 // The reserved TLSDESC entry in the PLT for an executable.
537 static unsigned char tlsdesc_plt_entry
[plt_entry_size
];
539 // Set the final size.
541 set_final_data_size();
543 // Write out the PLT data.
545 do_write(Output_file
*);
547 // The reloc section.
550 Output_data_got
<64, false>* got_
;
551 // The .got.plt section.
552 Output_data_space
* got_plt_
;
553 // The number of PLT entries.
555 // Offset of the reserved TLSDESC_GOT entry when needed.
556 unsigned int tlsdesc_got_offset_
;
559 // Create the PLT section. The ordinary .got section is an argument,
560 // since we need to refer to the start. We also create our own .got
561 // section just for PLT entries.
563 Output_data_plt_x86_64::Output_data_plt_x86_64(Layout
* layout
,
564 Output_data_got
<64, false>* got
,
565 Output_data_space
* got_plt
)
566 : Output_section_data(8), got_(got
), got_plt_(got_plt
), count_(0),
567 tlsdesc_got_offset_(-1U)
569 this->rel_
= new Reloc_section(false);
570 layout
->add_output_section_data(".rela.plt", elfcpp::SHT_RELA
,
571 elfcpp::SHF_ALLOC
, this->rel_
);
575 Output_data_plt_x86_64::do_adjust_output_section(Output_section
* os
)
577 // UnixWare sets the entsize of .plt to 4, and so does the old GNU
578 // linker, and so do we.
582 // Add an entry to the PLT.
585 Output_data_plt_x86_64::add_entry(Symbol
* gsym
)
587 gold_assert(!gsym
->has_plt_offset());
589 // Note that when setting the PLT offset we skip the initial
590 // reserved PLT entry.
591 gsym
->set_plt_offset((this->count_
+ 1) * plt_entry_size
);
595 section_offset_type got_offset
= this->got_plt_
->current_data_size();
597 // Every PLT entry needs a GOT entry which points back to the PLT
598 // entry (this will be changed by the dynamic linker, normally
599 // lazily when the function is called).
600 this->got_plt_
->set_current_data_size(got_offset
+ 8);
602 // Every PLT entry needs a reloc.
603 gsym
->set_needs_dynsym_entry();
604 this->rel_
->add_global(gsym
, elfcpp::R_X86_64_JUMP_SLOT
, this->got_plt_
,
607 // Note that we don't need to save the symbol. The contents of the
608 // PLT are independent of which symbols are used. The symbols only
609 // appear in the relocations.
612 // Set the final size.
614 Output_data_plt_x86_64::set_final_data_size()
616 unsigned int count
= this->count_
;
617 if (this->has_tlsdesc_entry())
619 this->set_data_size((count
+ 1) * plt_entry_size
);
622 // The first entry in the PLT for an executable.
624 unsigned char Output_data_plt_x86_64::first_plt_entry
[plt_entry_size
] =
626 // From AMD64 ABI Draft 0.98, page 76
627 0xff, 0x35, // pushq contents of memory address
628 0, 0, 0, 0, // replaced with address of .got + 8
629 0xff, 0x25, // jmp indirect
630 0, 0, 0, 0, // replaced with address of .got + 16
631 0x90, 0x90, 0x90, 0x90 // noop (x4)
634 // Subsequent entries in the PLT for an executable.
636 unsigned char Output_data_plt_x86_64::plt_entry
[plt_entry_size
] =
638 // From AMD64 ABI Draft 0.98, page 76
639 0xff, 0x25, // jmpq indirect
640 0, 0, 0, 0, // replaced with address of symbol in .got
641 0x68, // pushq immediate
642 0, 0, 0, 0, // replaced with offset into relocation table
643 0xe9, // jmpq relative
644 0, 0, 0, 0 // replaced with offset to start of .plt
647 // The reserved TLSDESC entry in the PLT for an executable.
649 unsigned char Output_data_plt_x86_64::tlsdesc_plt_entry
[plt_entry_size
] =
651 // From Alexandre Oliva, "Thread-Local Storage Descriptors for IA32
652 // and AMD64/EM64T", Version 0.9.4 (2005-10-10).
653 0xff, 0x35, // pushq x(%rip)
654 0, 0, 0, 0, // replaced with address of linkmap GOT entry (at PLTGOT + 8)
655 0xff, 0x25, // jmpq *y(%rip)
656 0, 0, 0, 0, // replaced with offset of reserved TLSDESC_GOT entry
661 // Write out the PLT. This uses the hand-coded instructions above,
662 // and adjusts them as needed. This is specified by the AMD64 ABI.
665 Output_data_plt_x86_64::do_write(Output_file
* of
)
667 const off_t offset
= this->offset();
668 const section_size_type oview_size
=
669 convert_to_section_size_type(this->data_size());
670 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
672 const off_t got_file_offset
= this->got_plt_
->offset();
673 const section_size_type got_size
=
674 convert_to_section_size_type(this->got_plt_
->data_size());
675 unsigned char* const got_view
= of
->get_output_view(got_file_offset
,
678 unsigned char* pov
= oview
;
680 // The base address of the .plt section.
681 elfcpp::Elf_types
<64>::Elf_Addr plt_address
= this->address();
682 // The base address of the .got section.
683 elfcpp::Elf_types
<64>::Elf_Addr got_base
= this->got_
->address();
684 // The base address of the PLT portion of the .got section,
685 // which is where the GOT pointer will point, and where the
686 // three reserved GOT entries are located.
687 elfcpp::Elf_types
<64>::Elf_Addr got_address
= this->got_plt_
->address();
689 memcpy(pov
, first_plt_entry
, plt_entry_size
);
690 // We do a jmp relative to the PC at the end of this instruction.
691 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
693 - (plt_address
+ 6)));
694 elfcpp::Swap
<32, false>::writeval(pov
+ 8,
696 - (plt_address
+ 12)));
697 pov
+= plt_entry_size
;
699 unsigned char* got_pov
= got_view
;
701 memset(got_pov
, 0, 24);
704 unsigned int plt_offset
= plt_entry_size
;
705 unsigned int got_offset
= 24;
706 const unsigned int count
= this->count_
;
707 for (unsigned int plt_index
= 0;
710 pov
+= plt_entry_size
,
712 plt_offset
+= plt_entry_size
,
715 // Set and adjust the PLT entry itself.
716 memcpy(pov
, plt_entry
, plt_entry_size
);
717 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
718 (got_address
+ got_offset
719 - (plt_address
+ plt_offset
722 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 7, plt_index
);
723 elfcpp::Swap
<32, false>::writeval(pov
+ 12,
724 - (plt_offset
+ plt_entry_size
));
726 // Set the entry in the GOT.
727 elfcpp::Swap
<64, false>::writeval(got_pov
, plt_address
+ plt_offset
+ 6);
730 if (this->has_tlsdesc_entry())
732 // Set and adjust the reserved TLSDESC PLT entry.
733 unsigned int tlsdesc_got_offset
= this->get_tlsdesc_got_offset();
734 memcpy(pov
, tlsdesc_plt_entry
, plt_entry_size
);
735 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
737 - (plt_address
+ plt_offset
739 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 8,
742 - (plt_address
+ plt_offset
744 pov
+= plt_entry_size
;
747 gold_assert(static_cast<section_size_type
>(pov
- oview
) == oview_size
);
748 gold_assert(static_cast<section_size_type
>(got_pov
- got_view
) == got_size
);
750 of
->write_output_view(offset
, oview_size
, oview
);
751 of
->write_output_view(got_file_offset
, got_size
, got_view
);
754 // Create the PLT section.
757 Target_x86_64::make_plt_section(Symbol_table
* symtab
, Layout
* layout
)
759 if (this->plt_
== NULL
)
761 // Create the GOT sections first.
762 this->got_section(symtab
, layout
);
764 this->plt_
= new Output_data_plt_x86_64(layout
, this->got_
,
766 layout
->add_output_section_data(".plt", elfcpp::SHT_PROGBITS
,
768 | elfcpp::SHF_EXECINSTR
),
773 // Create a PLT entry for a global symbol.
776 Target_x86_64::make_plt_entry(Symbol_table
* symtab
, Layout
* layout
,
779 if (gsym
->has_plt_offset())
782 if (this->plt_
== NULL
)
783 this->make_plt_section(symtab
, layout
);
785 this->plt_
->add_entry(gsym
);
788 // Define the _TLS_MODULE_BASE_ symbol at the end of the TLS segment.
791 Target_x86_64::define_tls_base_symbol(Symbol_table
* symtab
, Layout
* layout
)
793 if (this->tls_base_symbol_defined_
)
796 Output_segment
* tls_segment
= layout
->tls_segment();
797 if (tls_segment
!= NULL
)
799 symtab
->define_in_output_segment("_TLS_MODULE_BASE_", NULL
,
803 elfcpp::STV_HIDDEN
, 0,
804 Symbol::SEGMENT_END
, true);
806 this->tls_base_symbol_defined_
= true;
809 // Create the reserved PLT and GOT entries for the TLS descriptor resolver.
812 Target_x86_64::reserve_tlsdesc_entries(Symbol_table
* symtab
,
815 if (this->plt_
== NULL
)
816 this->make_plt_section(symtab
, layout
);
818 if (!this->plt_
->has_tlsdesc_entry())
820 // Allocate the TLSDESC_GOT entry.
821 Output_data_got
<64, false>* got
= this->got_section(symtab
, layout
);
822 unsigned int got_offset
= got
->add_constant(0);
824 // Allocate the TLSDESC_PLT entry.
825 this->plt_
->reserve_tlsdesc_entry(got_offset
);
829 // Create a GOT entry for the TLS module index.
832 Target_x86_64::got_mod_index_entry(Symbol_table
* symtab
, Layout
* layout
,
833 Sized_relobj
<64, false>* object
)
835 if (this->got_mod_index_offset_
== -1U)
837 gold_assert(symtab
!= NULL
&& layout
!= NULL
&& object
!= NULL
);
838 Reloc_section
* rela_dyn
= this->rela_dyn_section(layout
);
839 Output_data_got
<64, false>* got
= this->got_section(symtab
, layout
);
840 unsigned int got_offset
= got
->add_constant(0);
841 rela_dyn
->add_local(object
, 0, elfcpp::R_X86_64_DTPMOD64
, got
,
843 got
->add_constant(0);
844 this->got_mod_index_offset_
= got_offset
;
846 return this->got_mod_index_offset_
;
849 // Optimize the TLS relocation type based on what we know about the
850 // symbol. IS_FINAL is true if the final address of this symbol is
851 // known at link time.
853 tls::Tls_optimization
854 Target_x86_64::optimize_tls_reloc(bool is_final
, int r_type
)
856 // If we are generating a shared library, then we can't do anything
858 if (parameters
->options().shared())
859 return tls::TLSOPT_NONE
;
863 case elfcpp::R_X86_64_TLSGD
:
864 case elfcpp::R_X86_64_GOTPC32_TLSDESC
:
865 case elfcpp::R_X86_64_TLSDESC_CALL
:
866 // These are General-Dynamic which permits fully general TLS
867 // access. Since we know that we are generating an executable,
868 // we can convert this to Initial-Exec. If we also know that
869 // this is a local symbol, we can further switch to Local-Exec.
871 return tls::TLSOPT_TO_LE
;
872 return tls::TLSOPT_TO_IE
;
874 case elfcpp::R_X86_64_TLSLD
:
875 // This is Local-Dynamic, which refers to a local symbol in the
876 // dynamic TLS block. Since we know that we generating an
877 // executable, we can switch to Local-Exec.
878 return tls::TLSOPT_TO_LE
;
880 case elfcpp::R_X86_64_DTPOFF32
:
881 case elfcpp::R_X86_64_DTPOFF64
:
882 // Another Local-Dynamic reloc.
883 return tls::TLSOPT_TO_LE
;
885 case elfcpp::R_X86_64_GOTTPOFF
:
886 // These are Initial-Exec relocs which get the thread offset
887 // from the GOT. If we know that we are linking against the
888 // local symbol, we can switch to Local-Exec, which links the
889 // thread offset into the instruction.
891 return tls::TLSOPT_TO_LE
;
892 return tls::TLSOPT_NONE
;
894 case elfcpp::R_X86_64_TPOFF32
:
895 // When we already have Local-Exec, there is nothing further we
897 return tls::TLSOPT_NONE
;
904 // Report an unsupported relocation against a local symbol.
907 Target_x86_64::Scan::unsupported_reloc_local(Sized_relobj
<64, false>* object
,
910 gold_error(_("%s: unsupported reloc %u against local symbol"),
911 object
->name().c_str(), r_type
);
914 // We are about to emit a dynamic relocation of type R_TYPE. If the
915 // dynamic linker does not support it, issue an error. The GNU linker
916 // only issues a non-PIC error for an allocated read-only section.
917 // Here we know the section is allocated, but we don't know that it is
918 // read-only. But we check for all the relocation types which the
919 // glibc dynamic linker supports, so it seems appropriate to issue an
920 // error even if the section is not read-only.
923 Target_x86_64::Scan::check_non_pic(Relobj
* object
, unsigned int r_type
)
927 // These are the relocation types supported by glibc for x86_64.
928 case elfcpp::R_X86_64_RELATIVE
:
929 case elfcpp::R_X86_64_GLOB_DAT
:
930 case elfcpp::R_X86_64_JUMP_SLOT
:
931 case elfcpp::R_X86_64_DTPMOD64
:
932 case elfcpp::R_X86_64_DTPOFF64
:
933 case elfcpp::R_X86_64_TPOFF64
:
934 case elfcpp::R_X86_64_64
:
935 case elfcpp::R_X86_64_32
:
936 case elfcpp::R_X86_64_PC32
:
937 case elfcpp::R_X86_64_COPY
:
941 // This prevents us from issuing more than one error per reloc
942 // section. But we can still wind up issuing more than one
943 // error per object file.
944 if (this->issued_non_pic_error_
)
946 object
->error(_("requires unsupported dynamic reloc; "
947 "recompile with -fPIC"));
948 this->issued_non_pic_error_
= true;
951 case elfcpp::R_X86_64_NONE
:
956 // Scan a relocation for a local symbol.
959 Target_x86_64::Scan::local(const General_options
&,
960 Symbol_table
* symtab
,
962 Target_x86_64
* target
,
963 Sized_relobj
<64, false>* object
,
964 unsigned int data_shndx
,
965 Output_section
* output_section
,
966 const elfcpp::Rela
<64, false>& reloc
,
968 const elfcpp::Sym
<64, false>& lsym
)
972 case elfcpp::R_X86_64_NONE
:
973 case elfcpp::R_386_GNU_VTINHERIT
:
974 case elfcpp::R_386_GNU_VTENTRY
:
977 case elfcpp::R_X86_64_64
:
978 // If building a shared library (or a position-independent
979 // executable), we need to create a dynamic relocation for this
980 // location. The relocation applied at link time will apply the
981 // link-time value, so we flag the location with an
982 // R_X86_64_RELATIVE relocation so the dynamic loader can
983 // relocate it easily.
984 if (parameters
->options().output_is_position_independent())
986 unsigned int r_sym
= elfcpp::elf_r_sym
<64>(reloc
.get_r_info());
987 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
988 rela_dyn
->add_local_relative(object
, r_sym
,
989 elfcpp::R_X86_64_RELATIVE
,
990 output_section
, data_shndx
,
991 reloc
.get_r_offset(),
992 reloc
.get_r_addend());
996 case elfcpp::R_X86_64_32
:
997 case elfcpp::R_X86_64_32S
:
998 case elfcpp::R_X86_64_16
:
999 case elfcpp::R_X86_64_8
:
1000 // If building a shared library (or a position-independent
1001 // executable), we need to create a dynamic relocation for this
1002 // location. We can't use an R_X86_64_RELATIVE relocation
1003 // because that is always a 64-bit relocation.
1004 if (parameters
->options().output_is_position_independent())
1006 this->check_non_pic(object
, r_type
);
1008 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
1009 unsigned int r_sym
= elfcpp::elf_r_sym
<64>(reloc
.get_r_info());
1010 if (lsym
.get_st_type() != elfcpp::STT_SECTION
)
1011 rela_dyn
->add_local(object
, r_sym
, r_type
, output_section
,
1012 data_shndx
, reloc
.get_r_offset(),
1013 reloc
.get_r_addend());
1016 gold_assert(lsym
.get_st_value() == 0);
1017 unsigned int shndx
= lsym
.get_st_shndx();
1019 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
,
1022 object
->error(_("section symbol %u has bad shndx %u"),
1025 rela_dyn
->add_local_section(object
, shndx
,
1026 r_type
, output_section
,
1027 data_shndx
, reloc
.get_r_offset(),
1028 reloc
.get_r_addend());
1033 case elfcpp::R_X86_64_PC64
:
1034 case elfcpp::R_X86_64_PC32
:
1035 case elfcpp::R_X86_64_PC16
:
1036 case elfcpp::R_X86_64_PC8
:
1039 case elfcpp::R_X86_64_PLT32
:
1040 // Since we know this is a local symbol, we can handle this as a
1044 case elfcpp::R_X86_64_GOTPC32
:
1045 case elfcpp::R_X86_64_GOTOFF64
:
1046 case elfcpp::R_X86_64_GOTPC64
:
1047 case elfcpp::R_X86_64_PLTOFF64
:
1048 // We need a GOT section.
1049 target
->got_section(symtab
, layout
);
1050 // For PLTOFF64, we'd normally want a PLT section, but since we
1051 // know this is a local symbol, no PLT is needed.
1054 case elfcpp::R_X86_64_GOT64
:
1055 case elfcpp::R_X86_64_GOT32
:
1056 case elfcpp::R_X86_64_GOTPCREL64
:
1057 case elfcpp::R_X86_64_GOTPCREL
:
1058 case elfcpp::R_X86_64_GOTPLT64
:
1060 // The symbol requires a GOT entry.
1061 Output_data_got
<64, false>* got
= target
->got_section(symtab
, layout
);
1062 unsigned int r_sym
= elfcpp::elf_r_sym
<64>(reloc
.get_r_info());
1063 if (got
->add_local(object
, r_sym
, GOT_TYPE_STANDARD
))
1065 // If we are generating a shared object, we need to add a
1066 // dynamic relocation for this symbol's GOT entry.
1067 if (parameters
->options().output_is_position_independent())
1069 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
1070 // R_X86_64_RELATIVE assumes a 64-bit relocation.
1071 if (r_type
!= elfcpp::R_X86_64_GOT32
)
1072 rela_dyn
->add_local_relative(
1073 object
, r_sym
, elfcpp::R_X86_64_RELATIVE
, got
,
1074 object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
), 0);
1077 this->check_non_pic(object
, r_type
);
1079 gold_assert(lsym
.get_st_type() != elfcpp::STT_SECTION
);
1080 rela_dyn
->add_local(
1081 object
, r_sym
, r_type
, got
,
1082 object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
), 0);
1086 // For GOTPLT64, we'd normally want a PLT section, but since
1087 // we know this is a local symbol, no PLT is needed.
1091 case elfcpp::R_X86_64_COPY
:
1092 case elfcpp::R_X86_64_GLOB_DAT
:
1093 case elfcpp::R_X86_64_JUMP_SLOT
:
1094 case elfcpp::R_X86_64_RELATIVE
:
1095 // These are outstanding tls relocs, which are unexpected when linking
1096 case elfcpp::R_X86_64_TPOFF64
:
1097 case elfcpp::R_X86_64_DTPMOD64
:
1098 case elfcpp::R_X86_64_TLSDESC
:
1099 gold_error(_("%s: unexpected reloc %u in object file"),
1100 object
->name().c_str(), r_type
);
1103 // These are initial tls relocs, which are expected when linking
1104 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
1105 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
1106 case elfcpp::R_X86_64_TLSDESC_CALL
:
1107 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
1108 case elfcpp::R_X86_64_DTPOFF32
:
1109 case elfcpp::R_X86_64_DTPOFF64
:
1110 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
1111 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
1113 bool output_is_shared
= parameters
->options().shared();
1114 const tls::Tls_optimization optimized_type
1115 = Target_x86_64::optimize_tls_reloc(!output_is_shared
, r_type
);
1118 case elfcpp::R_X86_64_TLSGD
: // General-dynamic
1119 if (optimized_type
== tls::TLSOPT_NONE
)
1121 // Create a pair of GOT entries for the module index and
1122 // dtv-relative offset.
1123 Output_data_got
<64, false>* got
1124 = target
->got_section(symtab
, layout
);
1125 unsigned int r_sym
= elfcpp::elf_r_sym
<64>(reloc
.get_r_info());
1126 unsigned int shndx
= lsym
.get_st_shndx();
1128 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
, &is_ordinary
);
1130 object
->error(_("local symbol %u has bad shndx %u"),
1133 got
->add_local_pair_with_rela(object
, r_sym
,
1136 target
->rela_dyn_section(layout
),
1137 elfcpp::R_X86_64_DTPMOD64
, 0);
1139 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1140 unsupported_reloc_local(object
, r_type
);
1143 case elfcpp::R_X86_64_GOTPC32_TLSDESC
:
1144 target
->define_tls_base_symbol(symtab
, layout
);
1145 if (optimized_type
== tls::TLSOPT_NONE
)
1147 // Create reserved PLT and GOT entries for the resolver.
1148 target
->reserve_tlsdesc_entries(symtab
, layout
);
1150 // Generate a double GOT entry with an R_X86_64_TLSDESC reloc.
1151 Output_data_got
<64, false>* got
1152 = target
->got_section(symtab
, layout
);
1153 unsigned int r_sym
= elfcpp::elf_r_sym
<64>(reloc
.get_r_info());
1154 unsigned int shndx
= lsym
.get_st_shndx();
1156 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
, &is_ordinary
);
1158 object
->error(_("local symbol %u has bad shndx %u"),
1161 got
->add_local_pair_with_rela(object
, r_sym
,
1164 target
->rela_dyn_section(layout
),
1165 elfcpp::R_X86_64_TLSDESC
, 0);
1167 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1168 unsupported_reloc_local(object
, r_type
);
1171 case elfcpp::R_X86_64_TLSDESC_CALL
:
1174 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
1175 if (optimized_type
== tls::TLSOPT_NONE
)
1177 // Create a GOT entry for the module index.
1178 target
->got_mod_index_entry(symtab
, layout
, object
);
1180 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1181 unsupported_reloc_local(object
, r_type
);
1184 case elfcpp::R_X86_64_DTPOFF32
:
1185 case elfcpp::R_X86_64_DTPOFF64
:
1188 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
1189 layout
->set_has_static_tls();
1190 if (optimized_type
== tls::TLSOPT_NONE
)
1192 // Create a GOT entry for the tp-relative offset.
1193 Output_data_got
<64, false>* got
1194 = target
->got_section(symtab
, layout
);
1195 unsigned int r_sym
= elfcpp::elf_r_sym
<64>(reloc
.get_r_info());
1196 got
->add_local_with_rela(object
, r_sym
, GOT_TYPE_TLS_OFFSET
,
1197 target
->rela_dyn_section(layout
),
1198 elfcpp::R_X86_64_TPOFF64
);
1200 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1201 unsupported_reloc_local(object
, r_type
);
1204 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
1205 layout
->set_has_static_tls();
1206 if (output_is_shared
)
1207 unsupported_reloc_local(object
, r_type
);
1216 case elfcpp::R_X86_64_SIZE32
:
1217 case elfcpp::R_X86_64_SIZE64
:
1219 gold_error(_("%s: unsupported reloc %u against local symbol"),
1220 object
->name().c_str(), r_type
);
1226 // Report an unsupported relocation against a global symbol.
1229 Target_x86_64::Scan::unsupported_reloc_global(Sized_relobj
<64, false>* object
,
1230 unsigned int r_type
,
1233 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
1234 object
->name().c_str(), r_type
, gsym
->demangled_name().c_str());
1237 // Scan a relocation for a global symbol.
1240 Target_x86_64::Scan::global(const General_options
&,
1241 Symbol_table
* symtab
,
1243 Target_x86_64
* target
,
1244 Sized_relobj
<64, false>* object
,
1245 unsigned int data_shndx
,
1246 Output_section
* output_section
,
1247 const elfcpp::Rela
<64, false>& reloc
,
1248 unsigned int r_type
,
1253 case elfcpp::R_X86_64_NONE
:
1254 case elfcpp::R_386_GNU_VTINHERIT
:
1255 case elfcpp::R_386_GNU_VTENTRY
:
1258 case elfcpp::R_X86_64_64
:
1259 case elfcpp::R_X86_64_32
:
1260 case elfcpp::R_X86_64_32S
:
1261 case elfcpp::R_X86_64_16
:
1262 case elfcpp::R_X86_64_8
:
1264 // Make a PLT entry if necessary.
1265 if (gsym
->needs_plt_entry())
1267 target
->make_plt_entry(symtab
, layout
, gsym
);
1268 // Since this is not a PC-relative relocation, we may be
1269 // taking the address of a function. In that case we need to
1270 // set the entry in the dynamic symbol table to the address of
1272 if (gsym
->is_from_dynobj() && !parameters
->options().shared())
1273 gsym
->set_needs_dynsym_value();
1275 // Make a dynamic relocation if necessary.
1276 if (gsym
->needs_dynamic_reloc(Symbol::ABSOLUTE_REF
))
1278 if (target
->may_need_copy_reloc(gsym
))
1280 target
->copy_reloc(symtab
, layout
, object
,
1281 data_shndx
, output_section
, gsym
, reloc
);
1283 else if (r_type
== elfcpp::R_X86_64_64
1284 && gsym
->can_use_relative_reloc(false))
1286 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
1287 rela_dyn
->add_global_relative(gsym
, elfcpp::R_X86_64_RELATIVE
,
1288 output_section
, object
,
1289 data_shndx
, reloc
.get_r_offset(),
1290 reloc
.get_r_addend());
1294 this->check_non_pic(object
, r_type
);
1295 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
1296 rela_dyn
->add_global(gsym
, r_type
, output_section
, object
,
1297 data_shndx
, reloc
.get_r_offset(),
1298 reloc
.get_r_addend());
1304 case elfcpp::R_X86_64_PC64
:
1305 case elfcpp::R_X86_64_PC32
:
1306 case elfcpp::R_X86_64_PC16
:
1307 case elfcpp::R_X86_64_PC8
:
1309 // Make a PLT entry if necessary.
1310 if (gsym
->needs_plt_entry())
1311 target
->make_plt_entry(symtab
, layout
, gsym
);
1312 // Make a dynamic relocation if necessary.
1313 int flags
= Symbol::NON_PIC_REF
;
1314 if (gsym
->type() == elfcpp::STT_FUNC
)
1315 flags
|= Symbol::FUNCTION_CALL
;
1316 if (gsym
->needs_dynamic_reloc(flags
))
1318 if (target
->may_need_copy_reloc(gsym
))
1320 target
->copy_reloc(symtab
, layout
, object
,
1321 data_shndx
, output_section
, gsym
, reloc
);
1325 this->check_non_pic(object
, r_type
);
1326 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
1327 rela_dyn
->add_global(gsym
, r_type
, output_section
, object
,
1328 data_shndx
, reloc
.get_r_offset(),
1329 reloc
.get_r_addend());
1335 case elfcpp::R_X86_64_GOT64
:
1336 case elfcpp::R_X86_64_GOT32
:
1337 case elfcpp::R_X86_64_GOTPCREL64
:
1338 case elfcpp::R_X86_64_GOTPCREL
:
1339 case elfcpp::R_X86_64_GOTPLT64
:
1341 // The symbol requires a GOT entry.
1342 Output_data_got
<64, false>* got
= target
->got_section(symtab
, layout
);
1343 if (gsym
->final_value_is_known())
1344 got
->add_global(gsym
, GOT_TYPE_STANDARD
);
1347 // If this symbol is not fully resolved, we need to add a
1348 // dynamic relocation for it.
1349 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
1350 if (gsym
->is_from_dynobj()
1351 || gsym
->is_undefined()
1352 || gsym
->is_preemptible())
1353 got
->add_global_with_rela(gsym
, GOT_TYPE_STANDARD
, rela_dyn
,
1354 elfcpp::R_X86_64_GLOB_DAT
);
1357 if (got
->add_global(gsym
, GOT_TYPE_STANDARD
))
1358 rela_dyn
->add_global_relative(
1359 gsym
, elfcpp::R_X86_64_RELATIVE
, got
,
1360 gsym
->got_offset(GOT_TYPE_STANDARD
), 0);
1363 // For GOTPLT64, we also need a PLT entry (but only if the
1364 // symbol is not fully resolved).
1365 if (r_type
== elfcpp::R_X86_64_GOTPLT64
1366 && !gsym
->final_value_is_known())
1367 target
->make_plt_entry(symtab
, layout
, gsym
);
1371 case elfcpp::R_X86_64_PLT32
:
1372 // If the symbol is fully resolved, this is just a PC32 reloc.
1373 // Otherwise we need a PLT entry.
1374 if (gsym
->final_value_is_known())
1376 // If building a shared library, we can also skip the PLT entry
1377 // if the symbol is defined in the output file and is protected
1379 if (gsym
->is_defined()
1380 && !gsym
->is_from_dynobj()
1381 && !gsym
->is_preemptible())
1383 target
->make_plt_entry(symtab
, layout
, gsym
);
1386 case elfcpp::R_X86_64_GOTPC32
:
1387 case elfcpp::R_X86_64_GOTOFF64
:
1388 case elfcpp::R_X86_64_GOTPC64
:
1389 case elfcpp::R_X86_64_PLTOFF64
:
1390 // We need a GOT section.
1391 target
->got_section(symtab
, layout
);
1392 // For PLTOFF64, we also need a PLT entry (but only if the
1393 // symbol is not fully resolved).
1394 if (r_type
== elfcpp::R_X86_64_PLTOFF64
1395 && !gsym
->final_value_is_known())
1396 target
->make_plt_entry(symtab
, layout
, gsym
);
1399 case elfcpp::R_X86_64_COPY
:
1400 case elfcpp::R_X86_64_GLOB_DAT
:
1401 case elfcpp::R_X86_64_JUMP_SLOT
:
1402 case elfcpp::R_X86_64_RELATIVE
:
1403 // These are outstanding tls relocs, which are unexpected when linking
1404 case elfcpp::R_X86_64_TPOFF64
:
1405 case elfcpp::R_X86_64_DTPMOD64
:
1406 case elfcpp::R_X86_64_TLSDESC
:
1407 gold_error(_("%s: unexpected reloc %u in object file"),
1408 object
->name().c_str(), r_type
);
1411 // These are initial tls relocs, which are expected for global()
1412 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
1413 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
1414 case elfcpp::R_X86_64_TLSDESC_CALL
:
1415 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
1416 case elfcpp::R_X86_64_DTPOFF32
:
1417 case elfcpp::R_X86_64_DTPOFF64
:
1418 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
1419 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
1421 const bool is_final
= gsym
->final_value_is_known();
1422 const tls::Tls_optimization optimized_type
1423 = Target_x86_64::optimize_tls_reloc(is_final
, r_type
);
1426 case elfcpp::R_X86_64_TLSGD
: // General-dynamic
1427 if (optimized_type
== tls::TLSOPT_NONE
)
1429 // Create a pair of GOT entries for the module index and
1430 // dtv-relative offset.
1431 Output_data_got
<64, false>* got
1432 = target
->got_section(symtab
, layout
);
1433 got
->add_global_pair_with_rela(gsym
, GOT_TYPE_TLS_PAIR
,
1434 target
->rela_dyn_section(layout
),
1435 elfcpp::R_X86_64_DTPMOD64
,
1436 elfcpp::R_X86_64_DTPOFF64
);
1438 else if (optimized_type
== tls::TLSOPT_TO_IE
)
1440 // Create a GOT entry for the tp-relative offset.
1441 Output_data_got
<64, false>* got
1442 = target
->got_section(symtab
, layout
);
1443 got
->add_global_with_rela(gsym
, GOT_TYPE_TLS_OFFSET
,
1444 target
->rela_dyn_section(layout
),
1445 elfcpp::R_X86_64_TPOFF64
);
1447 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1448 unsupported_reloc_global(object
, r_type
, gsym
);
1451 case elfcpp::R_X86_64_GOTPC32_TLSDESC
:
1452 target
->define_tls_base_symbol(symtab
, layout
);
1453 if (optimized_type
== tls::TLSOPT_NONE
)
1455 // Create reserved PLT and GOT entries for the resolver.
1456 target
->reserve_tlsdesc_entries(symtab
, layout
);
1458 // Create a double GOT entry with an R_X86_64_TLSDESC reloc.
1459 Output_data_got
<64, false>* got
1460 = target
->got_section(symtab
, layout
);
1461 got
->add_global_pair_with_rela(gsym
, GOT_TYPE_TLS_DESC
,
1462 target
->rela_dyn_section(layout
),
1463 elfcpp::R_X86_64_TLSDESC
, 0);
1465 else if (optimized_type
== tls::TLSOPT_TO_IE
)
1467 // Create a GOT entry for the tp-relative offset.
1468 Output_data_got
<64, false>* got
1469 = target
->got_section(symtab
, layout
);
1470 got
->add_global_with_rela(gsym
, GOT_TYPE_TLS_OFFSET
,
1471 target
->rela_dyn_section(layout
),
1472 elfcpp::R_X86_64_TPOFF64
);
1474 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1475 unsupported_reloc_global(object
, r_type
, gsym
);
1478 case elfcpp::R_X86_64_TLSDESC_CALL
:
1481 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
1482 if (optimized_type
== tls::TLSOPT_NONE
)
1484 // Create a GOT entry for the module index.
1485 target
->got_mod_index_entry(symtab
, layout
, object
);
1487 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1488 unsupported_reloc_global(object
, r_type
, gsym
);
1491 case elfcpp::R_X86_64_DTPOFF32
:
1492 case elfcpp::R_X86_64_DTPOFF64
:
1495 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
1496 layout
->set_has_static_tls();
1497 if (optimized_type
== tls::TLSOPT_NONE
)
1499 // Create a GOT entry for the tp-relative offset.
1500 Output_data_got
<64, false>* got
1501 = target
->got_section(symtab
, layout
);
1502 got
->add_global_with_rela(gsym
, GOT_TYPE_TLS_OFFSET
,
1503 target
->rela_dyn_section(layout
),
1504 elfcpp::R_X86_64_TPOFF64
);
1506 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1507 unsupported_reloc_global(object
, r_type
, gsym
);
1510 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
1511 layout
->set_has_static_tls();
1512 if (parameters
->options().shared())
1513 unsupported_reloc_local(object
, r_type
);
1522 case elfcpp::R_X86_64_SIZE32
:
1523 case elfcpp::R_X86_64_SIZE64
:
1525 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
1526 object
->name().c_str(), r_type
,
1527 gsym
->demangled_name().c_str());
1532 // Scan relocations for a section.
1535 Target_x86_64::scan_relocs(const General_options
& options
,
1536 Symbol_table
* symtab
,
1538 Sized_relobj
<64, false>* object
,
1539 unsigned int data_shndx
,
1540 unsigned int sh_type
,
1541 const unsigned char* prelocs
,
1543 Output_section
* output_section
,
1544 bool needs_special_offset_handling
,
1545 size_t local_symbol_count
,
1546 const unsigned char* plocal_symbols
)
1548 if (sh_type
== elfcpp::SHT_REL
)
1550 gold_error(_("%s: unsupported REL reloc section"),
1551 object
->name().c_str());
1555 gold::scan_relocs
<64, false, Target_x86_64
, elfcpp::SHT_RELA
,
1556 Target_x86_64::Scan
>(
1566 needs_special_offset_handling
,
1571 // Finalize the sections.
1574 Target_x86_64::do_finalize_sections(Layout
* layout
)
1576 // Fill in some more dynamic tags.
1577 Output_data_dynamic
* const odyn
= layout
->dynamic_data();
1580 if (this->got_plt_
!= NULL
)
1581 odyn
->add_section_address(elfcpp::DT_PLTGOT
, this->got_plt_
);
1583 if (this->plt_
!= NULL
)
1585 const Output_data
* od
= this->plt_
->rel_plt();
1586 odyn
->add_section_size(elfcpp::DT_PLTRELSZ
, od
);
1587 odyn
->add_section_address(elfcpp::DT_JMPREL
, od
);
1588 odyn
->add_constant(elfcpp::DT_PLTREL
, elfcpp::DT_RELA
);
1589 if (this->plt_
->has_tlsdesc_entry())
1591 unsigned int plt_offset
= this->plt_
->get_tlsdesc_plt_offset();
1592 unsigned int got_offset
= this->plt_
->get_tlsdesc_got_offset();
1593 this->got_
->finalize_data_size();
1594 odyn
->add_section_plus_offset(elfcpp::DT_TLSDESC_PLT
,
1595 this->plt_
, plt_offset
);
1596 odyn
->add_section_plus_offset(elfcpp::DT_TLSDESC_GOT
,
1597 this->got_
, got_offset
);
1601 if (this->rela_dyn_
!= NULL
)
1603 const Output_data
* od
= this->rela_dyn_
;
1604 odyn
->add_section_address(elfcpp::DT_RELA
, od
);
1605 odyn
->add_section_size(elfcpp::DT_RELASZ
, od
);
1606 odyn
->add_constant(elfcpp::DT_RELAENT
,
1607 elfcpp::Elf_sizes
<64>::rela_size
);
1610 if (!parameters
->options().shared())
1612 // The value of the DT_DEBUG tag is filled in by the dynamic
1613 // linker at run time, and used by the debugger.
1614 odyn
->add_constant(elfcpp::DT_DEBUG
, 0);
1618 // Emit any relocs we saved in an attempt to avoid generating COPY
1620 if (this->copy_relocs_
.any_saved_relocs())
1621 this->copy_relocs_
.emit(this->rela_dyn_section(layout
));
1624 // Perform a relocation.
1627 Target_x86_64::Relocate::relocate(const Relocate_info
<64, false>* relinfo
,
1628 Target_x86_64
* target
,
1630 const elfcpp::Rela
<64, false>& rela
,
1631 unsigned int r_type
,
1632 const Sized_symbol
<64>* gsym
,
1633 const Symbol_value
<64>* psymval
,
1634 unsigned char* view
,
1635 elfcpp::Elf_types
<64>::Elf_Addr address
,
1636 section_size_type view_size
)
1638 if (this->skip_call_tls_get_addr_
)
1640 if (r_type
!= elfcpp::R_X86_64_PLT32
1642 || strcmp(gsym
->name(), "__tls_get_addr") != 0)
1644 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
1645 _("missing expected TLS relocation"));
1649 this->skip_call_tls_get_addr_
= false;
1654 // Pick the value to use for symbols defined in shared objects.
1655 Symbol_value
<64> symval
;
1657 && (gsym
->is_from_dynobj()
1658 || (parameters
->options().shared()
1659 && (gsym
->is_undefined() || gsym
->is_preemptible())))
1660 && gsym
->has_plt_offset())
1662 symval
.set_output_value(target
->plt_section()->address()
1663 + gsym
->plt_offset());
1667 const Sized_relobj
<64, false>* object
= relinfo
->object
;
1668 const elfcpp::Elf_Xword addend
= rela
.get_r_addend();
1670 // Get the GOT offset if needed.
1671 // The GOT pointer points to the end of the GOT section.
1672 // We need to subtract the size of the GOT section to get
1673 // the actual offset to use in the relocation.
1674 bool have_got_offset
= false;
1675 unsigned int got_offset
= 0;
1678 case elfcpp::R_X86_64_GOT32
:
1679 case elfcpp::R_X86_64_GOT64
:
1680 case elfcpp::R_X86_64_GOTPLT64
:
1681 case elfcpp::R_X86_64_GOTPCREL
:
1682 case elfcpp::R_X86_64_GOTPCREL64
:
1685 gold_assert(gsym
->has_got_offset(GOT_TYPE_STANDARD
));
1686 got_offset
= gsym
->got_offset(GOT_TYPE_STANDARD
) - target
->got_size();
1690 unsigned int r_sym
= elfcpp::elf_r_sym
<64>(rela
.get_r_info());
1691 gold_assert(object
->local_has_got_offset(r_sym
, GOT_TYPE_STANDARD
));
1692 got_offset
= (object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
)
1693 - target
->got_size());
1695 have_got_offset
= true;
1704 case elfcpp::R_X86_64_NONE
:
1705 case elfcpp::R_386_GNU_VTINHERIT
:
1706 case elfcpp::R_386_GNU_VTENTRY
:
1709 case elfcpp::R_X86_64_64
:
1710 Relocate_functions
<64, false>::rela64(view
, object
, psymval
, addend
);
1713 case elfcpp::R_X86_64_PC64
:
1714 Relocate_functions
<64, false>::pcrela64(view
, object
, psymval
, addend
,
1718 case elfcpp::R_X86_64_32
:
1719 // FIXME: we need to verify that value + addend fits into 32 bits:
1720 // uint64_t x = value + addend;
1721 // x == static_cast<uint64_t>(static_cast<uint32_t>(x))
1722 // Likewise for other <=32-bit relocations (but see R_X86_64_32S).
1723 Relocate_functions
<64, false>::rela32(view
, object
, psymval
, addend
);
1726 case elfcpp::R_X86_64_32S
:
1727 // FIXME: we need to verify that value + addend fits into 32 bits:
1728 // int64_t x = value + addend; // note this quantity is signed!
1729 // x == static_cast<int64_t>(static_cast<int32_t>(x))
1730 Relocate_functions
<64, false>::rela32(view
, object
, psymval
, addend
);
1733 case elfcpp::R_X86_64_PC32
:
1734 Relocate_functions
<64, false>::pcrela32(view
, object
, psymval
, addend
,
1738 case elfcpp::R_X86_64_16
:
1739 Relocate_functions
<64, false>::rela16(view
, object
, psymval
, addend
);
1742 case elfcpp::R_X86_64_PC16
:
1743 Relocate_functions
<64, false>::pcrela16(view
, object
, psymval
, addend
,
1747 case elfcpp::R_X86_64_8
:
1748 Relocate_functions
<64, false>::rela8(view
, object
, psymval
, addend
);
1751 case elfcpp::R_X86_64_PC8
:
1752 Relocate_functions
<64, false>::pcrela8(view
, object
, psymval
, addend
,
1756 case elfcpp::R_X86_64_PLT32
:
1757 gold_assert(gsym
== NULL
1758 || gsym
->has_plt_offset()
1759 || gsym
->final_value_is_known()
1760 || (gsym
->is_defined()
1761 && !gsym
->is_from_dynobj()
1762 && !gsym
->is_preemptible()));
1763 // Note: while this code looks the same as for R_X86_64_PC32, it
1764 // behaves differently because psymval was set to point to
1765 // the PLT entry, rather than the symbol, in Scan::global().
1766 Relocate_functions
<64, false>::pcrela32(view
, object
, psymval
, addend
,
1770 case elfcpp::R_X86_64_PLTOFF64
:
1773 gold_assert(gsym
->has_plt_offset()
1774 || gsym
->final_value_is_known());
1775 elfcpp::Elf_types
<64>::Elf_Addr got_address
;
1776 got_address
= target
->got_section(NULL
, NULL
)->address();
1777 Relocate_functions
<64, false>::rela64(view
, object
, psymval
,
1778 addend
- got_address
);
1781 case elfcpp::R_X86_64_GOT32
:
1782 gold_assert(have_got_offset
);
1783 Relocate_functions
<64, false>::rela32(view
, got_offset
, addend
);
1786 case elfcpp::R_X86_64_GOTPC32
:
1789 elfcpp::Elf_types
<64>::Elf_Addr value
;
1790 value
= target
->got_plt_section()->address();
1791 Relocate_functions
<64, false>::pcrela32(view
, value
, addend
, address
);
1795 case elfcpp::R_X86_64_GOT64
:
1796 // The ABI doc says "Like GOT64, but indicates a PLT entry is needed."
1797 // Since we always add a PLT entry, this is equivalent.
1798 case elfcpp::R_X86_64_GOTPLT64
:
1799 gold_assert(have_got_offset
);
1800 Relocate_functions
<64, false>::rela64(view
, got_offset
, addend
);
1803 case elfcpp::R_X86_64_GOTPC64
:
1806 elfcpp::Elf_types
<64>::Elf_Addr value
;
1807 value
= target
->got_plt_section()->address();
1808 Relocate_functions
<64, false>::pcrela64(view
, value
, addend
, address
);
1812 case elfcpp::R_X86_64_GOTOFF64
:
1814 elfcpp::Elf_types
<64>::Elf_Addr value
;
1815 value
= (psymval
->value(object
, 0)
1816 - target
->got_plt_section()->address());
1817 Relocate_functions
<64, false>::rela64(view
, value
, addend
);
1821 case elfcpp::R_X86_64_GOTPCREL
:
1823 gold_assert(have_got_offset
);
1824 elfcpp::Elf_types
<64>::Elf_Addr value
;
1825 value
= target
->got_plt_section()->address() + got_offset
;
1826 Relocate_functions
<64, false>::pcrela32(view
, value
, addend
, address
);
1830 case elfcpp::R_X86_64_GOTPCREL64
:
1832 gold_assert(have_got_offset
);
1833 elfcpp::Elf_types
<64>::Elf_Addr value
;
1834 value
= target
->got_plt_section()->address() + got_offset
;
1835 Relocate_functions
<64, false>::pcrela64(view
, value
, addend
, address
);
1839 case elfcpp::R_X86_64_COPY
:
1840 case elfcpp::R_X86_64_GLOB_DAT
:
1841 case elfcpp::R_X86_64_JUMP_SLOT
:
1842 case elfcpp::R_X86_64_RELATIVE
:
1843 // These are outstanding tls relocs, which are unexpected when linking
1844 case elfcpp::R_X86_64_TPOFF64
:
1845 case elfcpp::R_X86_64_DTPMOD64
:
1846 case elfcpp::R_X86_64_TLSDESC
:
1847 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
1848 _("unexpected reloc %u in object file"),
1852 // These are initial tls relocs, which are expected when linking
1853 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
1854 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
1855 case elfcpp::R_X86_64_TLSDESC_CALL
:
1856 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
1857 case elfcpp::R_X86_64_DTPOFF32
:
1858 case elfcpp::R_X86_64_DTPOFF64
:
1859 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
1860 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
1861 this->relocate_tls(relinfo
, target
, relnum
, rela
, r_type
, gsym
, psymval
,
1862 view
, address
, view_size
);
1865 case elfcpp::R_X86_64_SIZE32
:
1866 case elfcpp::R_X86_64_SIZE64
:
1868 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
1869 _("unsupported reloc %u"),
1877 // Perform a TLS relocation.
1880 Target_x86_64::Relocate::relocate_tls(const Relocate_info
<64, false>* relinfo
,
1881 Target_x86_64
* target
,
1883 const elfcpp::Rela
<64, false>& rela
,
1884 unsigned int r_type
,
1885 const Sized_symbol
<64>* gsym
,
1886 const Symbol_value
<64>* psymval
,
1887 unsigned char* view
,
1888 elfcpp::Elf_types
<64>::Elf_Addr address
,
1889 section_size_type view_size
)
1891 Output_segment
* tls_segment
= relinfo
->layout
->tls_segment();
1893 const Sized_relobj
<64, false>* object
= relinfo
->object
;
1894 const elfcpp::Elf_Xword addend
= rela
.get_r_addend();
1896 elfcpp::Elf_types
<64>::Elf_Addr value
= psymval
->value(relinfo
->object
, 0);
1898 const bool is_final
= (gsym
== NULL
1899 ? !parameters
->options().output_is_position_independent()
1900 : gsym
->final_value_is_known());
1901 const tls::Tls_optimization optimized_type
1902 = Target_x86_64::optimize_tls_reloc(is_final
, r_type
);
1905 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
1906 this->saw_tls_block_reloc_
= true;
1907 if (optimized_type
== tls::TLSOPT_TO_LE
)
1909 gold_assert(tls_segment
!= NULL
);
1910 this->tls_gd_to_le(relinfo
, relnum
, tls_segment
,
1911 rela
, r_type
, value
, view
,
1917 unsigned int got_type
= (optimized_type
== tls::TLSOPT_TO_IE
1918 ? GOT_TYPE_TLS_OFFSET
1919 : GOT_TYPE_TLS_PAIR
);
1920 unsigned int got_offset
;
1923 gold_assert(gsym
->has_got_offset(got_type
));
1924 got_offset
= gsym
->got_offset(got_type
) - target
->got_size();
1928 unsigned int r_sym
= elfcpp::elf_r_sym
<64>(rela
.get_r_info());
1929 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
1930 got_offset
= (object
->local_got_offset(r_sym
, got_type
)
1931 - target
->got_size());
1933 if (optimized_type
== tls::TLSOPT_TO_IE
)
1935 gold_assert(tls_segment
!= NULL
);
1936 value
= target
->got_plt_section()->address() + got_offset
;
1937 this->tls_gd_to_ie(relinfo
, relnum
, tls_segment
, rela
, r_type
,
1938 value
, view
, address
, view_size
);
1941 else if (optimized_type
== tls::TLSOPT_NONE
)
1943 // Relocate the field with the offset of the pair of GOT
1945 value
= target
->got_plt_section()->address() + got_offset
;
1946 Relocate_functions
<64, false>::pcrela32(view
, value
, addend
,
1951 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
1952 _("unsupported reloc %u"), r_type
);
1955 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
1956 case elfcpp::R_X86_64_TLSDESC_CALL
:
1957 this->saw_tls_block_reloc_
= true;
1958 if (optimized_type
== tls::TLSOPT_TO_LE
)
1960 gold_assert(tls_segment
!= NULL
);
1961 this->tls_desc_gd_to_le(relinfo
, relnum
, tls_segment
,
1962 rela
, r_type
, value
, view
,
1968 unsigned int got_type
= (optimized_type
== tls::TLSOPT_TO_IE
1969 ? GOT_TYPE_TLS_OFFSET
1970 : GOT_TYPE_TLS_DESC
);
1971 unsigned int got_offset
;
1974 gold_assert(gsym
->has_got_offset(got_type
));
1975 got_offset
= gsym
->got_offset(got_type
) - target
->got_size();
1979 unsigned int r_sym
= elfcpp::elf_r_sym
<64>(rela
.get_r_info());
1980 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
1981 got_offset
= (object
->local_got_offset(r_sym
, got_type
)
1982 - target
->got_size());
1984 if (optimized_type
== tls::TLSOPT_TO_IE
)
1986 gold_assert(tls_segment
!= NULL
);
1987 value
= target
->got_plt_section()->address() + got_offset
;
1988 this->tls_desc_gd_to_ie(relinfo
, relnum
, tls_segment
,
1989 rela
, r_type
, value
, view
, address
,
1993 else if (optimized_type
== tls::TLSOPT_NONE
)
1995 if (r_type
== elfcpp::R_X86_64_GOTPC32_TLSDESC
)
1997 // Relocate the field with the offset of the pair of GOT
1999 value
= target
->got_plt_section()->address() + got_offset
;
2000 Relocate_functions
<64, false>::pcrela32(view
, value
, addend
,
2006 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
2007 _("unsupported reloc %u"), r_type
);
2010 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
2011 this->saw_tls_block_reloc_
= true;
2012 if (optimized_type
== tls::TLSOPT_TO_LE
)
2014 gold_assert(tls_segment
!= NULL
);
2015 this->tls_ld_to_le(relinfo
, relnum
, tls_segment
, rela
, r_type
,
2016 value
, view
, view_size
);
2019 else if (optimized_type
== tls::TLSOPT_NONE
)
2021 // Relocate the field with the offset of the GOT entry for
2022 // the module index.
2023 unsigned int got_offset
;
2024 got_offset
= (target
->got_mod_index_entry(NULL
, NULL
, NULL
)
2025 - target
->got_size());
2026 value
= target
->got_plt_section()->address() + got_offset
;
2027 Relocate_functions
<64, false>::pcrela32(view
, value
, addend
,
2031 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
2032 _("unsupported reloc %u"), r_type
);
2035 case elfcpp::R_X86_64_DTPOFF32
:
2036 gold_assert(tls_segment
!= NULL
);
2037 if (optimized_type
== tls::TLSOPT_TO_LE
)
2039 // This relocation type is used in debugging information.
2040 // In that case we need to not optimize the value. If we
2041 // haven't seen a TLSLD reloc, then we assume we should not
2042 // optimize this reloc.
2043 if (this->saw_tls_block_reloc_
)
2044 value
-= tls_segment
->memsz();
2046 Relocate_functions
<64, false>::rela32(view
, value
, 0);
2049 case elfcpp::R_X86_64_DTPOFF64
:
2050 gold_assert(tls_segment
!= NULL
);
2051 if (optimized_type
== tls::TLSOPT_TO_LE
)
2053 // See R_X86_64_DTPOFF32, just above, for why we test this.
2054 if (this->saw_tls_block_reloc_
)
2055 value
-= tls_segment
->memsz();
2057 Relocate_functions
<64, false>::rela64(view
, value
, 0);
2060 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
2061 if (optimized_type
== tls::TLSOPT_TO_LE
)
2063 gold_assert(tls_segment
!= NULL
);
2064 Target_x86_64::Relocate::tls_ie_to_le(relinfo
, relnum
, tls_segment
,
2065 rela
, r_type
, value
, view
,
2069 else if (optimized_type
== tls::TLSOPT_NONE
)
2071 // Relocate the field with the offset of the GOT entry for
2072 // the tp-relative offset of the symbol.
2073 unsigned int got_offset
;
2076 gold_assert(gsym
->has_got_offset(GOT_TYPE_TLS_OFFSET
));
2077 got_offset
= (gsym
->got_offset(GOT_TYPE_TLS_OFFSET
)
2078 - target
->got_size());
2082 unsigned int r_sym
= elfcpp::elf_r_sym
<64>(rela
.get_r_info());
2083 gold_assert(object
->local_has_got_offset(r_sym
,
2084 GOT_TYPE_TLS_OFFSET
));
2085 got_offset
= (object
->local_got_offset(r_sym
, GOT_TYPE_TLS_OFFSET
)
2086 - target
->got_size());
2088 value
= target
->got_plt_section()->address() + got_offset
;
2089 Relocate_functions
<64, false>::pcrela32(view
, value
, addend
, address
);
2092 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
2093 _("unsupported reloc type %u"),
2097 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
2098 value
-= tls_segment
->memsz();
2099 Relocate_functions
<64, false>::rela32(view
, value
, 0);
2104 // Do a relocation in which we convert a TLS General-Dynamic to an
2108 Target_x86_64::Relocate::tls_gd_to_ie(const Relocate_info
<64, false>* relinfo
,
2111 const elfcpp::Rela
<64, false>& rela
,
2113 elfcpp::Elf_types
<64>::Elf_Addr value
,
2114 unsigned char* view
,
2115 elfcpp::Elf_types
<64>::Elf_Addr address
,
2116 section_size_type view_size
)
2118 // .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
2119 // .word 0x6666; rex64; call __tls_get_addr
2120 // ==> movq %fs:0,%rax; addq x@gottpoff(%rip),%rax
2122 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -4);
2123 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 12);
2125 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
2126 (memcmp(view
- 4, "\x66\x48\x8d\x3d", 4) == 0));
2127 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
2128 (memcmp(view
+ 4, "\x66\x66\x48\xe8", 4) == 0));
2130 memcpy(view
- 4, "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x03\x05\0\0\0\0", 16);
2132 const elfcpp::Elf_Xword addend
= rela
.get_r_addend();
2133 Relocate_functions
<64, false>::pcrela32(view
+ 8, value
, addend
- 8, address
);
2135 // The next reloc should be a PLT32 reloc against __tls_get_addr.
2137 this->skip_call_tls_get_addr_
= true;
2140 // Do a relocation in which we convert a TLS General-Dynamic to a
2144 Target_x86_64::Relocate::tls_gd_to_le(const Relocate_info
<64, false>* relinfo
,
2146 Output_segment
* tls_segment
,
2147 const elfcpp::Rela
<64, false>& rela
,
2149 elfcpp::Elf_types
<64>::Elf_Addr value
,
2150 unsigned char* view
,
2151 section_size_type view_size
)
2153 // .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
2154 // .word 0x6666; rex64; call __tls_get_addr
2155 // ==> movq %fs:0,%rax; leaq x@tpoff(%rax),%rax
2157 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -4);
2158 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 12);
2160 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
2161 (memcmp(view
- 4, "\x66\x48\x8d\x3d", 4) == 0));
2162 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
2163 (memcmp(view
+ 4, "\x66\x66\x48\xe8", 4) == 0));
2165 memcpy(view
- 4, "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0\0", 16);
2167 value
-= tls_segment
->memsz();
2168 Relocate_functions
<64, false>::rela32(view
+ 8, value
, 0);
2170 // The next reloc should be a PLT32 reloc against __tls_get_addr.
2172 this->skip_call_tls_get_addr_
= true;
2175 // Do a TLSDESC-style General-Dynamic to Initial-Exec transition.
2178 Target_x86_64::Relocate::tls_desc_gd_to_ie(
2179 const Relocate_info
<64, false>* relinfo
,
2182 const elfcpp::Rela
<64, false>& rela
,
2183 unsigned int r_type
,
2184 elfcpp::Elf_types
<64>::Elf_Addr value
,
2185 unsigned char* view
,
2186 elfcpp::Elf_types
<64>::Elf_Addr address
,
2187 section_size_type view_size
)
2189 if (r_type
== elfcpp::R_X86_64_GOTPC32_TLSDESC
)
2191 // leaq foo@tlsdesc(%rip), %rax
2192 // ==> movq foo@gottpoff(%rip), %rax
2193 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -3);
2194 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 4);
2195 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
2196 view
[-3] == 0x48 && view
[-2] == 0x8d && view
[-1] == 0x05);
2198 const elfcpp::Elf_Xword addend
= rela
.get_r_addend();
2199 Relocate_functions
<64, false>::pcrela32(view
, value
, addend
, address
);
2203 // call *foo@tlscall(%rax)
2205 gold_assert(r_type
== elfcpp::R_X86_64_TLSDESC_CALL
);
2206 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 2);
2207 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
2208 view
[0] == 0xff && view
[1] == 0x10);
2214 // Do a TLSDESC-style General-Dynamic to Local-Exec transition.
2217 Target_x86_64::Relocate::tls_desc_gd_to_le(
2218 const Relocate_info
<64, false>* relinfo
,
2220 Output_segment
* tls_segment
,
2221 const elfcpp::Rela
<64, false>& rela
,
2222 unsigned int r_type
,
2223 elfcpp::Elf_types
<64>::Elf_Addr value
,
2224 unsigned char* view
,
2225 section_size_type view_size
)
2227 if (r_type
== elfcpp::R_X86_64_GOTPC32_TLSDESC
)
2229 // leaq foo@tlsdesc(%rip), %rax
2230 // ==> movq foo@tpoff, %rax
2231 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -3);
2232 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 4);
2233 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
2234 view
[-3] == 0x48 && view
[-2] == 0x8d && view
[-1] == 0x05);
2237 value
-= tls_segment
->memsz();
2238 Relocate_functions
<64, false>::rela32(view
, value
, 0);
2242 // call *foo@tlscall(%rax)
2244 gold_assert(r_type
== elfcpp::R_X86_64_TLSDESC_CALL
);
2245 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 2);
2246 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
2247 view
[0] == 0xff && view
[1] == 0x10);
2254 Target_x86_64::Relocate::tls_ld_to_le(const Relocate_info
<64, false>* relinfo
,
2257 const elfcpp::Rela
<64, false>& rela
,
2259 elfcpp::Elf_types
<64>::Elf_Addr
,
2260 unsigned char* view
,
2261 section_size_type view_size
)
2263 // leaq foo@tlsld(%rip),%rdi; call __tls_get_addr@plt;
2264 // ... leq foo@dtpoff(%rax),%reg
2265 // ==> .word 0x6666; .byte 0x66; movq %fs:0,%rax ... leaq x@tpoff(%rax),%rdx
2267 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -3);
2268 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 9);
2270 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
2271 view
[-3] == 0x48 && view
[-2] == 0x8d && view
[-1] == 0x3d);
2273 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(), view
[4] == 0xe8);
2275 memcpy(view
- 3, "\x66\x66\x66\x64\x48\x8b\x04\x25\0\0\0\0", 12);
2277 // The next reloc should be a PLT32 reloc against __tls_get_addr.
2279 this->skip_call_tls_get_addr_
= true;
2282 // Do a relocation in which we convert a TLS Initial-Exec to a
2286 Target_x86_64::Relocate::tls_ie_to_le(const Relocate_info
<64, false>* relinfo
,
2288 Output_segment
* tls_segment
,
2289 const elfcpp::Rela
<64, false>& rela
,
2291 elfcpp::Elf_types
<64>::Elf_Addr value
,
2292 unsigned char* view
,
2293 section_size_type view_size
)
2295 // We need to examine the opcodes to figure out which instruction we
2298 // movq foo@gottpoff(%rip),%reg ==> movq $YY,%reg
2299 // addq foo@gottpoff(%rip),%reg ==> addq $YY,%reg
2301 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -3);
2302 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 4);
2304 unsigned char op1
= view
[-3];
2305 unsigned char op2
= view
[-2];
2306 unsigned char op3
= view
[-1];
2307 unsigned char reg
= op3
>> 3;
2315 view
[-1] = 0xc0 | reg
;
2319 // Special handling for %rsp.
2323 view
[-1] = 0xc0 | reg
;
2331 view
[-1] = 0x80 | reg
| (reg
<< 3);
2334 value
-= tls_segment
->memsz();
2335 Relocate_functions
<64, false>::rela32(view
, value
, 0);
2338 // Relocate section data.
2341 Target_x86_64::relocate_section(const Relocate_info
<64, false>* relinfo
,
2342 unsigned int sh_type
,
2343 const unsigned char* prelocs
,
2345 Output_section
* output_section
,
2346 bool needs_special_offset_handling
,
2347 unsigned char* view
,
2348 elfcpp::Elf_types
<64>::Elf_Addr address
,
2349 section_size_type view_size
)
2351 gold_assert(sh_type
== elfcpp::SHT_RELA
);
2353 gold::relocate_section
<64, false, Target_x86_64
, elfcpp::SHT_RELA
,
2354 Target_x86_64::Relocate
>(
2360 needs_special_offset_handling
,
2366 // Return the size of a relocation while scanning during a relocatable
2370 Target_x86_64::Relocatable_size_for_reloc::get_size_for_reloc(
2371 unsigned int r_type
,
2376 case elfcpp::R_X86_64_NONE
:
2377 case elfcpp::R_386_GNU_VTINHERIT
:
2378 case elfcpp::R_386_GNU_VTENTRY
:
2379 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
2380 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
2381 case elfcpp::R_X86_64_TLSDESC_CALL
:
2382 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
2383 case elfcpp::R_X86_64_DTPOFF32
:
2384 case elfcpp::R_X86_64_DTPOFF64
:
2385 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
2386 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
2389 case elfcpp::R_X86_64_64
:
2390 case elfcpp::R_X86_64_PC64
:
2391 case elfcpp::R_X86_64_GOTOFF64
:
2392 case elfcpp::R_X86_64_GOTPC64
:
2393 case elfcpp::R_X86_64_PLTOFF64
:
2394 case elfcpp::R_X86_64_GOT64
:
2395 case elfcpp::R_X86_64_GOTPCREL64
:
2396 case elfcpp::R_X86_64_GOTPCREL
:
2397 case elfcpp::R_X86_64_GOTPLT64
:
2400 case elfcpp::R_X86_64_32
:
2401 case elfcpp::R_X86_64_32S
:
2402 case elfcpp::R_X86_64_PC32
:
2403 case elfcpp::R_X86_64_PLT32
:
2404 case elfcpp::R_X86_64_GOTPC32
:
2405 case elfcpp::R_X86_64_GOT32
:
2408 case elfcpp::R_X86_64_16
:
2409 case elfcpp::R_X86_64_PC16
:
2412 case elfcpp::R_X86_64_8
:
2413 case elfcpp::R_X86_64_PC8
:
2416 case elfcpp::R_X86_64_COPY
:
2417 case elfcpp::R_X86_64_GLOB_DAT
:
2418 case elfcpp::R_X86_64_JUMP_SLOT
:
2419 case elfcpp::R_X86_64_RELATIVE
:
2420 // These are outstanding tls relocs, which are unexpected when linking
2421 case elfcpp::R_X86_64_TPOFF64
:
2422 case elfcpp::R_X86_64_DTPMOD64
:
2423 case elfcpp::R_X86_64_TLSDESC
:
2424 object
->error(_("unexpected reloc %u in object file"), r_type
);
2427 case elfcpp::R_X86_64_SIZE32
:
2428 case elfcpp::R_X86_64_SIZE64
:
2430 object
->error(_("unsupported reloc %u against local symbol"), r_type
);
2435 // Scan the relocs during a relocatable link.
2438 Target_x86_64::scan_relocatable_relocs(const General_options
& options
,
2439 Symbol_table
* symtab
,
2441 Sized_relobj
<64, false>* object
,
2442 unsigned int data_shndx
,
2443 unsigned int sh_type
,
2444 const unsigned char* prelocs
,
2446 Output_section
* output_section
,
2447 bool needs_special_offset_handling
,
2448 size_t local_symbol_count
,
2449 const unsigned char* plocal_symbols
,
2450 Relocatable_relocs
* rr
)
2452 gold_assert(sh_type
== elfcpp::SHT_RELA
);
2454 typedef gold::Default_scan_relocatable_relocs
<elfcpp::SHT_RELA
,
2455 Relocatable_size_for_reloc
> Scan_relocatable_relocs
;
2457 gold::scan_relocatable_relocs
<64, false, elfcpp::SHT_RELA
,
2458 Scan_relocatable_relocs
>(
2467 needs_special_offset_handling
,
2473 // Relocate a section during a relocatable link.
2476 Target_x86_64::relocate_for_relocatable(
2477 const Relocate_info
<64, false>* relinfo
,
2478 unsigned int sh_type
,
2479 const unsigned char* prelocs
,
2481 Output_section
* output_section
,
2482 off_t offset_in_output_section
,
2483 const Relocatable_relocs
* rr
,
2484 unsigned char* view
,
2485 elfcpp::Elf_types
<64>::Elf_Addr view_address
,
2486 section_size_type view_size
,
2487 unsigned char* reloc_view
,
2488 section_size_type reloc_view_size
)
2490 gold_assert(sh_type
== elfcpp::SHT_RELA
);
2492 gold::relocate_for_relocatable
<64, false, elfcpp::SHT_RELA
>(
2497 offset_in_output_section
,
2506 // Return the value to use for a dynamic which requires special
2507 // treatment. This is how we support equality comparisons of function
2508 // pointers across shared library boundaries, as described in the
2509 // processor specific ABI supplement.
2512 Target_x86_64::do_dynsym_value(const Symbol
* gsym
) const
2514 gold_assert(gsym
->is_from_dynobj() && gsym
->has_plt_offset());
2515 return this->plt_section()->address() + gsym
->plt_offset();
2518 // Return a string used to fill a code section with nops to take up
2519 // the specified length.
2522 Target_x86_64::do_code_fill(section_size_type length
) const
2526 // Build a jmpq instruction to skip over the bytes.
2527 unsigned char jmp
[5];
2529 elfcpp::Swap_unaligned
<32, false>::writeval(jmp
+ 1, length
- 5);
2530 return (std::string(reinterpret_cast<char*>(&jmp
[0]), 5)
2531 + std::string(length
- 5, '\0'));
2534 // Nop sequences of various lengths.
2535 const char nop1
[1] = { 0x90 }; // nop
2536 const char nop2
[2] = { 0x66, 0x90 }; // xchg %ax %ax
2537 const char nop3
[3] = { 0x8d, 0x76, 0x00 }; // leal 0(%esi),%esi
2538 const char nop4
[4] = { 0x8d, 0x74, 0x26, 0x00}; // leal 0(%esi,1),%esi
2539 const char nop5
[5] = { 0x90, 0x8d, 0x74, 0x26, // nop
2540 0x00 }; // leal 0(%esi,1),%esi
2541 const char nop6
[6] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2543 const char nop7
[7] = { 0x8d, 0xb4, 0x26, 0x00, // leal 0L(%esi,1),%esi
2545 const char nop8
[8] = { 0x90, 0x8d, 0xb4, 0x26, // nop
2546 0x00, 0x00, 0x00, 0x00 }; // leal 0L(%esi,1),%esi
2547 const char nop9
[9] = { 0x89, 0xf6, 0x8d, 0xbc, // movl %esi,%esi
2548 0x27, 0x00, 0x00, 0x00, // leal 0L(%edi,1),%edi
2550 const char nop10
[10] = { 0x8d, 0x76, 0x00, 0x8d, // leal 0(%esi),%esi
2551 0xbc, 0x27, 0x00, 0x00, // leal 0L(%edi,1),%edi
2553 const char nop11
[11] = { 0x8d, 0x74, 0x26, 0x00, // leal 0(%esi,1),%esi
2554 0x8d, 0xbc, 0x27, 0x00, // leal 0L(%edi,1),%edi
2556 const char nop12
[12] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2557 0x00, 0x00, 0x8d, 0xbf, // leal 0L(%edi),%edi
2558 0x00, 0x00, 0x00, 0x00 };
2559 const char nop13
[13] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2560 0x00, 0x00, 0x8d, 0xbc, // leal 0L(%edi,1),%edi
2561 0x27, 0x00, 0x00, 0x00,
2563 const char nop14
[14] = { 0x8d, 0xb4, 0x26, 0x00, // leal 0L(%esi,1),%esi
2564 0x00, 0x00, 0x00, 0x8d, // leal 0L(%edi,1),%edi
2565 0xbc, 0x27, 0x00, 0x00,
2567 const char nop15
[15] = { 0xeb, 0x0d, 0x90, 0x90, // jmp .+15
2568 0x90, 0x90, 0x90, 0x90, // nop,nop,nop,...
2569 0x90, 0x90, 0x90, 0x90,
2572 const char* nops
[16] = {
2574 nop1
, nop2
, nop3
, nop4
, nop5
, nop6
, nop7
,
2575 nop8
, nop9
, nop10
, nop11
, nop12
, nop13
, nop14
, nop15
2578 return std::string(nops
[length
], length
);
2581 // The selector for x86_64 object files.
2583 class Target_selector_x86_64
: public Target_selector
2586 Target_selector_x86_64()
2587 : Target_selector(elfcpp::EM_X86_64
, 64, false, "elf64-x86-64")
2591 do_instantiate_target()
2592 { return new Target_x86_64(); }
2595 Target_selector_x86_64 target_selector_x86_64
;
2597 } // End anonymous namespace.