1 // x86_64.cc -- x86_64 target support for gold.
3 // Copyright 2006, 2007, 2008, 2009 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 gc_process_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 // Scan the relocations to look for symbol adjustments.
86 scan_relocs(const General_options
& options
,
89 Sized_relobj
<64, false>* object
,
90 unsigned int data_shndx
,
92 const unsigned char* prelocs
,
94 Output_section
* output_section
,
95 bool needs_special_offset_handling
,
96 size_t local_symbol_count
,
97 const unsigned char* plocal_symbols
);
99 // Finalize the sections.
101 do_finalize_sections(Layout
*);
103 // Return the value to use for a dynamic which requires special
106 do_dynsym_value(const Symbol
*) const;
108 // Relocate a section.
110 relocate_section(const Relocate_info
<64, false>*,
111 unsigned int sh_type
,
112 const unsigned char* prelocs
,
114 Output_section
* output_section
,
115 bool needs_special_offset_handling
,
117 elfcpp::Elf_types
<64>::Elf_Addr view_address
,
118 section_size_type view_size
);
120 // Scan the relocs during a relocatable link.
122 scan_relocatable_relocs(const General_options
& options
,
123 Symbol_table
* symtab
,
125 Sized_relobj
<64, false>* object
,
126 unsigned int data_shndx
,
127 unsigned int sh_type
,
128 const unsigned char* prelocs
,
130 Output_section
* output_section
,
131 bool needs_special_offset_handling
,
132 size_t local_symbol_count
,
133 const unsigned char* plocal_symbols
,
134 Relocatable_relocs
*);
136 // Relocate a section during a relocatable link.
138 relocate_for_relocatable(const Relocate_info
<64, false>*,
139 unsigned int sh_type
,
140 const unsigned char* prelocs
,
142 Output_section
* output_section
,
143 off_t offset_in_output_section
,
144 const Relocatable_relocs
*,
146 elfcpp::Elf_types
<64>::Elf_Addr view_address
,
147 section_size_type view_size
,
148 unsigned char* reloc_view
,
149 section_size_type reloc_view_size
);
151 // Return a string used to fill a code section with nops.
153 do_code_fill(section_size_type length
) const;
155 // Return whether SYM is defined by the ABI.
157 do_is_defined_by_abi(const Symbol
* sym
) const
158 { return strcmp(sym
->name(), "__tls_get_addr") == 0; }
160 // Return the size of the GOT section.
164 gold_assert(this->got_
!= NULL
);
165 return this->got_
->data_size();
169 // The class which scans relocations.
174 : issued_non_pic_error_(false)
178 local(const General_options
& options
, Symbol_table
* symtab
,
179 Layout
* layout
, Target_x86_64
* target
,
180 Sized_relobj
<64, false>* object
,
181 unsigned int data_shndx
,
182 Output_section
* output_section
,
183 const elfcpp::Rela
<64, false>& reloc
, unsigned int r_type
,
184 const elfcpp::Sym
<64, false>& lsym
);
187 global(const General_options
& options
, Symbol_table
* symtab
,
188 Layout
* layout
, Target_x86_64
* target
,
189 Sized_relobj
<64, false>* object
,
190 unsigned int data_shndx
,
191 Output_section
* output_section
,
192 const elfcpp::Rela
<64, false>& reloc
, unsigned int r_type
,
197 unsupported_reloc_local(Sized_relobj
<64, false>*, unsigned int r_type
);
200 unsupported_reloc_global(Sized_relobj
<64, false>*, unsigned int r_type
,
204 check_non_pic(Relobj
*, unsigned int r_type
);
206 // Whether we have issued an error about a non-PIC compilation.
207 bool issued_non_pic_error_
;
210 // The class which implements relocation.
215 : skip_call_tls_get_addr_(false), saw_tls_block_reloc_(false)
220 if (this->skip_call_tls_get_addr_
)
222 // FIXME: This needs to specify the location somehow.
223 gold_error(_("missing expected TLS relocation"));
227 // Do a relocation. Return false if the caller should not issue
228 // any warnings about this relocation.
230 relocate(const Relocate_info
<64, false>*, Target_x86_64
*, size_t relnum
,
231 const elfcpp::Rela
<64, false>&,
232 unsigned int r_type
, const Sized_symbol
<64>*,
233 const Symbol_value
<64>*,
234 unsigned char*, elfcpp::Elf_types
<64>::Elf_Addr
,
238 // Do a TLS relocation.
240 relocate_tls(const Relocate_info
<64, false>*, Target_x86_64
*,
241 size_t relnum
, const elfcpp::Rela
<64, false>&,
242 unsigned int r_type
, const Sized_symbol
<64>*,
243 const Symbol_value
<64>*,
244 unsigned char*, elfcpp::Elf_types
<64>::Elf_Addr
,
247 // Do a TLS General-Dynamic to Initial-Exec transition.
249 tls_gd_to_ie(const Relocate_info
<64, false>*, size_t relnum
,
250 Output_segment
* tls_segment
,
251 const elfcpp::Rela
<64, false>&, unsigned int r_type
,
252 elfcpp::Elf_types
<64>::Elf_Addr value
,
254 elfcpp::Elf_types
<64>::Elf_Addr
,
255 section_size_type view_size
);
257 // Do a TLS General-Dynamic to Local-Exec transition.
259 tls_gd_to_le(const Relocate_info
<64, false>*, size_t relnum
,
260 Output_segment
* tls_segment
,
261 const elfcpp::Rela
<64, false>&, unsigned int r_type
,
262 elfcpp::Elf_types
<64>::Elf_Addr value
,
264 section_size_type view_size
);
266 // Do a TLSDESC-style General-Dynamic to Initial-Exec transition.
268 tls_desc_gd_to_ie(const Relocate_info
<64, false>*, size_t relnum
,
269 Output_segment
* tls_segment
,
270 const elfcpp::Rela
<64, false>&, unsigned int r_type
,
271 elfcpp::Elf_types
<64>::Elf_Addr value
,
273 elfcpp::Elf_types
<64>::Elf_Addr
,
274 section_size_type view_size
);
276 // Do a TLSDESC-style General-Dynamic to Local-Exec transition.
278 tls_desc_gd_to_le(const Relocate_info
<64, false>*, size_t relnum
,
279 Output_segment
* tls_segment
,
280 const elfcpp::Rela
<64, false>&, unsigned int r_type
,
281 elfcpp::Elf_types
<64>::Elf_Addr value
,
283 section_size_type view_size
);
285 // Do a TLS Local-Dynamic to Local-Exec transition.
287 tls_ld_to_le(const Relocate_info
<64, false>*, size_t relnum
,
288 Output_segment
* tls_segment
,
289 const elfcpp::Rela
<64, false>&, unsigned int r_type
,
290 elfcpp::Elf_types
<64>::Elf_Addr value
,
292 section_size_type view_size
);
294 // Do a TLS Initial-Exec to Local-Exec transition.
296 tls_ie_to_le(const Relocate_info
<64, false>*, size_t relnum
,
297 Output_segment
* tls_segment
,
298 const elfcpp::Rela
<64, false>&, unsigned int r_type
,
299 elfcpp::Elf_types
<64>::Elf_Addr value
,
301 section_size_type view_size
);
303 // This is set if we should skip the next reloc, which should be a
304 // PLT32 reloc against ___tls_get_addr.
305 bool skip_call_tls_get_addr_
;
307 // This is set if we see a relocation which could load the address
308 // of the TLS block. Whether we see such a relocation determines
309 // how we handle the R_X86_64_DTPOFF32 relocation, which is used
310 // in debugging sections.
311 bool saw_tls_block_reloc_
;
314 // A class which returns the size required for a relocation type,
315 // used while scanning relocs during a relocatable link.
316 class Relocatable_size_for_reloc
320 get_size_for_reloc(unsigned int, Relobj
*);
323 // Adjust TLS relocation type based on the options and whether this
324 // is a local symbol.
325 static tls::Tls_optimization
326 optimize_tls_reloc(bool is_final
, int r_type
);
328 // Get the GOT section, creating it if necessary.
329 Output_data_got
<64, false>*
330 got_section(Symbol_table
*, Layout
*);
332 // Get the GOT PLT section.
334 got_plt_section() const
336 gold_assert(this->got_plt_
!= NULL
);
337 return this->got_plt_
;
340 // Create the PLT section.
342 make_plt_section(Symbol_table
* symtab
, Layout
* layout
);
344 // Create a PLT entry for a global symbol.
346 make_plt_entry(Symbol_table
*, Layout
*, Symbol
*);
348 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
350 define_tls_base_symbol(Symbol_table
*, Layout
*);
352 // Create the reserved PLT and GOT entries for the TLS descriptor resolver.
354 reserve_tlsdesc_entries(Symbol_table
* symtab
, Layout
* layout
);
356 // Create a GOT entry for the TLS module index.
358 got_mod_index_entry(Symbol_table
* symtab
, Layout
* layout
,
359 Sized_relobj
<64, false>* object
);
361 // Get the PLT section.
362 Output_data_plt_x86_64
*
365 gold_assert(this->plt_
!= NULL
);
369 // Get the dynamic reloc section, creating it if necessary.
371 rela_dyn_section(Layout
*);
373 // Return true if the symbol may need a COPY relocation.
374 // References from an executable object to non-function symbols
375 // defined in a dynamic object may need a COPY relocation.
377 may_need_copy_reloc(Symbol
* gsym
)
379 return (!parameters
->options().shared()
380 && gsym
->is_from_dynobj()
381 && gsym
->type() != elfcpp::STT_FUNC
);
384 // Add a potential copy relocation.
386 copy_reloc(Symbol_table
* symtab
, Layout
* layout
,
387 Sized_relobj
<64, false>* object
,
388 unsigned int shndx
, Output_section
* output_section
,
389 Symbol
* sym
, const elfcpp::Rela
<64, false>& reloc
)
391 this->copy_relocs_
.copy_reloc(symtab
, layout
,
392 symtab
->get_sized_symbol
<64>(sym
),
393 object
, shndx
, output_section
,
394 reloc
, this->rela_dyn_section(layout
));
397 // Information about this specific target which we pass to the
398 // general Target structure.
399 static const Target::Target_info x86_64_info
;
403 GOT_TYPE_STANDARD
= 0, // GOT entry for a regular symbol
404 GOT_TYPE_TLS_OFFSET
= 1, // GOT entry for TLS offset
405 GOT_TYPE_TLS_PAIR
= 2, // GOT entry for TLS module/offset pair
406 GOT_TYPE_TLS_DESC
= 3 // GOT entry for TLS_DESC pair
410 Output_data_got
<64, false>* got_
;
412 Output_data_plt_x86_64
* plt_
;
413 // The GOT PLT section.
414 Output_data_space
* got_plt_
;
415 // The dynamic reloc section.
416 Reloc_section
* rela_dyn_
;
417 // Relocs saved to avoid a COPY reloc.
418 Copy_relocs
<elfcpp::SHT_RELA
, 64, false> copy_relocs_
;
419 // Space for variables copied with a COPY reloc.
420 Output_data_space
* dynbss_
;
421 // Offset of the GOT entry for the TLS module index.
422 unsigned int got_mod_index_offset_
;
423 // True if the _TLS_MODULE_BASE_ symbol has been defined.
424 bool tls_base_symbol_defined_
;
427 const Target::Target_info
Target_x86_64::x86_64_info
=
430 false, // is_big_endian
431 elfcpp::EM_X86_64
, // machine_code
432 false, // has_make_symbol
433 false, // has_resolve
434 true, // has_code_fill
435 true, // is_default_stack_executable
437 "/lib/ld64.so.1", // program interpreter
438 0x400000, // default_text_segment_address
439 0x1000, // abi_pagesize (overridable by -z max-page-size)
440 0x1000 // common_pagesize (overridable by -z common-page-size)
443 // Get the GOT section, creating it if necessary.
445 Output_data_got
<64, false>*
446 Target_x86_64::got_section(Symbol_table
* symtab
, Layout
* layout
)
448 if (this->got_
== NULL
)
450 gold_assert(symtab
!= NULL
&& layout
!= NULL
);
452 this->got_
= new Output_data_got
<64, false>();
455 os
= layout
->add_output_section_data(".got", elfcpp::SHT_PROGBITS
,
457 | elfcpp::SHF_WRITE
),
461 // The old GNU linker creates a .got.plt section. We just
462 // create another set of data in the .got section. Note that we
463 // always create a PLT if we create a GOT, although the PLT
465 this->got_plt_
= new Output_data_space(8, "** GOT PLT");
466 os
= layout
->add_output_section_data(".got", elfcpp::SHT_PROGBITS
,
468 | elfcpp::SHF_WRITE
),
472 // The first three entries are reserved.
473 this->got_plt_
->set_current_data_size(3 * 8);
475 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
476 symtab
->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL
,
478 0, 0, elfcpp::STT_OBJECT
,
480 elfcpp::STV_HIDDEN
, 0,
487 // Get the dynamic reloc section, creating it if necessary.
489 Target_x86_64::Reloc_section
*
490 Target_x86_64::rela_dyn_section(Layout
* layout
)
492 if (this->rela_dyn_
== NULL
)
494 gold_assert(layout
!= NULL
);
495 this->rela_dyn_
= new Reloc_section(parameters
->options().combreloc());
496 layout
->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA
,
497 elfcpp::SHF_ALLOC
, this->rela_dyn_
);
499 return this->rela_dyn_
;
502 // A class to handle the PLT data.
504 class Output_data_plt_x86_64
: public Output_section_data
507 typedef Output_data_reloc
<elfcpp::SHT_RELA
, true, 64, false> Reloc_section
;
509 Output_data_plt_x86_64(Layout
*, Output_data_got
<64, false>*,
512 // Add an entry to the PLT.
514 add_entry(Symbol
* gsym
);
516 // Add the reserved TLSDESC_PLT entry to the PLT.
518 reserve_tlsdesc_entry(unsigned int got_offset
)
519 { this->tlsdesc_got_offset_
= got_offset
; }
521 // Return true if a TLSDESC_PLT entry has been reserved.
523 has_tlsdesc_entry() const
524 { return this->tlsdesc_got_offset_
!= -1U; }
526 // Return the GOT offset for the reserved TLSDESC_PLT entry.
528 get_tlsdesc_got_offset() const
529 { return this->tlsdesc_got_offset_
; }
531 // Return the offset of the reserved TLSDESC_PLT entry.
533 get_tlsdesc_plt_offset() const
534 { return (this->count_
+ 1) * plt_entry_size
; }
536 // Return the .rel.plt section data.
539 { return this->rel_
; }
543 do_adjust_output_section(Output_section
* os
);
545 // Write to a map file.
547 do_print_to_mapfile(Mapfile
* mapfile
) const
548 { mapfile
->print_output_data(this, _("** PLT")); }
551 // The size of an entry in the PLT.
552 static const int plt_entry_size
= 16;
554 // The first entry in the PLT.
555 // From the AMD64 ABI: "Unlike Intel386 ABI, this ABI uses the same
556 // procedure linkage table for both programs and shared objects."
557 static unsigned char first_plt_entry
[plt_entry_size
];
559 // Other entries in the PLT for an executable.
560 static unsigned char plt_entry
[plt_entry_size
];
562 // The reserved TLSDESC entry in the PLT for an executable.
563 static unsigned char tlsdesc_plt_entry
[plt_entry_size
];
565 // Set the final size.
567 set_final_data_size();
569 // Write out the PLT data.
571 do_write(Output_file
*);
573 // The reloc section.
576 Output_data_got
<64, false>* got_
;
577 // The .got.plt section.
578 Output_data_space
* got_plt_
;
579 // The number of PLT entries.
581 // Offset of the reserved TLSDESC_GOT entry when needed.
582 unsigned int tlsdesc_got_offset_
;
585 // Create the PLT section. The ordinary .got section is an argument,
586 // since we need to refer to the start. We also create our own .got
587 // section just for PLT entries.
589 Output_data_plt_x86_64::Output_data_plt_x86_64(Layout
* layout
,
590 Output_data_got
<64, false>* got
,
591 Output_data_space
* got_plt
)
592 : Output_section_data(8), got_(got
), got_plt_(got_plt
), count_(0),
593 tlsdesc_got_offset_(-1U)
595 this->rel_
= new Reloc_section(false);
596 layout
->add_output_section_data(".rela.plt", elfcpp::SHT_RELA
,
597 elfcpp::SHF_ALLOC
, this->rel_
);
601 Output_data_plt_x86_64::do_adjust_output_section(Output_section
* os
)
603 // UnixWare sets the entsize of .plt to 4, and so does the old GNU
604 // linker, and so do we.
608 // Add an entry to the PLT.
611 Output_data_plt_x86_64::add_entry(Symbol
* gsym
)
613 gold_assert(!gsym
->has_plt_offset());
615 // Note that when setting the PLT offset we skip the initial
616 // reserved PLT entry.
617 gsym
->set_plt_offset((this->count_
+ 1) * plt_entry_size
);
621 section_offset_type got_offset
= this->got_plt_
->current_data_size();
623 // Every PLT entry needs a GOT entry which points back to the PLT
624 // entry (this will be changed by the dynamic linker, normally
625 // lazily when the function is called).
626 this->got_plt_
->set_current_data_size(got_offset
+ 8);
628 // Every PLT entry needs a reloc.
629 gsym
->set_needs_dynsym_entry();
630 this->rel_
->add_global(gsym
, elfcpp::R_X86_64_JUMP_SLOT
, this->got_plt_
,
633 // Note that we don't need to save the symbol. The contents of the
634 // PLT are independent of which symbols are used. The symbols only
635 // appear in the relocations.
638 // Set the final size.
640 Output_data_plt_x86_64::set_final_data_size()
642 unsigned int count
= this->count_
;
643 if (this->has_tlsdesc_entry())
645 this->set_data_size((count
+ 1) * plt_entry_size
);
648 // The first entry in the PLT for an executable.
650 unsigned char Output_data_plt_x86_64::first_plt_entry
[plt_entry_size
] =
652 // From AMD64 ABI Draft 0.98, page 76
653 0xff, 0x35, // pushq contents of memory address
654 0, 0, 0, 0, // replaced with address of .got + 8
655 0xff, 0x25, // jmp indirect
656 0, 0, 0, 0, // replaced with address of .got + 16
657 0x90, 0x90, 0x90, 0x90 // noop (x4)
660 // Subsequent entries in the PLT for an executable.
662 unsigned char Output_data_plt_x86_64::plt_entry
[plt_entry_size
] =
664 // From AMD64 ABI Draft 0.98, page 76
665 0xff, 0x25, // jmpq indirect
666 0, 0, 0, 0, // replaced with address of symbol in .got
667 0x68, // pushq immediate
668 0, 0, 0, 0, // replaced with offset into relocation table
669 0xe9, // jmpq relative
670 0, 0, 0, 0 // replaced with offset to start of .plt
673 // The reserved TLSDESC entry in the PLT for an executable.
675 unsigned char Output_data_plt_x86_64::tlsdesc_plt_entry
[plt_entry_size
] =
677 // From Alexandre Oliva, "Thread-Local Storage Descriptors for IA32
678 // and AMD64/EM64T", Version 0.9.4 (2005-10-10).
679 0xff, 0x35, // pushq x(%rip)
680 0, 0, 0, 0, // replaced with address of linkmap GOT entry (at PLTGOT + 8)
681 0xff, 0x25, // jmpq *y(%rip)
682 0, 0, 0, 0, // replaced with offset of reserved TLSDESC_GOT entry
687 // Write out the PLT. This uses the hand-coded instructions above,
688 // and adjusts them as needed. This is specified by the AMD64 ABI.
691 Output_data_plt_x86_64::do_write(Output_file
* of
)
693 const off_t offset
= this->offset();
694 const section_size_type oview_size
=
695 convert_to_section_size_type(this->data_size());
696 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
698 const off_t got_file_offset
= this->got_plt_
->offset();
699 const section_size_type got_size
=
700 convert_to_section_size_type(this->got_plt_
->data_size());
701 unsigned char* const got_view
= of
->get_output_view(got_file_offset
,
704 unsigned char* pov
= oview
;
706 // The base address of the .plt section.
707 elfcpp::Elf_types
<64>::Elf_Addr plt_address
= this->address();
708 // The base address of the .got section.
709 elfcpp::Elf_types
<64>::Elf_Addr got_base
= this->got_
->address();
710 // The base address of the PLT portion of the .got section,
711 // which is where the GOT pointer will point, and where the
712 // three reserved GOT entries are located.
713 elfcpp::Elf_types
<64>::Elf_Addr got_address
= this->got_plt_
->address();
715 memcpy(pov
, first_plt_entry
, plt_entry_size
);
716 // We do a jmp relative to the PC at the end of this instruction.
717 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
719 - (plt_address
+ 6)));
720 elfcpp::Swap
<32, false>::writeval(pov
+ 8,
722 - (plt_address
+ 12)));
723 pov
+= plt_entry_size
;
725 unsigned char* got_pov
= got_view
;
727 memset(got_pov
, 0, 24);
730 unsigned int plt_offset
= plt_entry_size
;
731 unsigned int got_offset
= 24;
732 const unsigned int count
= this->count_
;
733 for (unsigned int plt_index
= 0;
736 pov
+= plt_entry_size
,
738 plt_offset
+= plt_entry_size
,
741 // Set and adjust the PLT entry itself.
742 memcpy(pov
, plt_entry
, plt_entry_size
);
743 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
744 (got_address
+ got_offset
745 - (plt_address
+ plt_offset
748 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 7, plt_index
);
749 elfcpp::Swap
<32, false>::writeval(pov
+ 12,
750 - (plt_offset
+ plt_entry_size
));
752 // Set the entry in the GOT.
753 elfcpp::Swap
<64, false>::writeval(got_pov
, plt_address
+ plt_offset
+ 6);
756 if (this->has_tlsdesc_entry())
758 // Set and adjust the reserved TLSDESC PLT entry.
759 unsigned int tlsdesc_got_offset
= this->get_tlsdesc_got_offset();
760 memcpy(pov
, tlsdesc_plt_entry
, plt_entry_size
);
761 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
763 - (plt_address
+ plt_offset
765 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 8,
768 - (plt_address
+ plt_offset
770 pov
+= plt_entry_size
;
773 gold_assert(static_cast<section_size_type
>(pov
- oview
) == oview_size
);
774 gold_assert(static_cast<section_size_type
>(got_pov
- got_view
) == got_size
);
776 of
->write_output_view(offset
, oview_size
, oview
);
777 of
->write_output_view(got_file_offset
, got_size
, got_view
);
780 // Create the PLT section.
783 Target_x86_64::make_plt_section(Symbol_table
* symtab
, Layout
* layout
)
785 if (this->plt_
== NULL
)
787 // Create the GOT sections first.
788 this->got_section(symtab
, layout
);
790 this->plt_
= new Output_data_plt_x86_64(layout
, this->got_
,
792 layout
->add_output_section_data(".plt", elfcpp::SHT_PROGBITS
,
794 | elfcpp::SHF_EXECINSTR
),
799 // Create a PLT entry for a global symbol.
802 Target_x86_64::make_plt_entry(Symbol_table
* symtab
, Layout
* layout
,
805 if (gsym
->has_plt_offset())
808 if (this->plt_
== NULL
)
809 this->make_plt_section(symtab
, layout
);
811 this->plt_
->add_entry(gsym
);
814 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
817 Target_x86_64::define_tls_base_symbol(Symbol_table
* symtab
, Layout
* layout
)
819 if (this->tls_base_symbol_defined_
)
822 Output_segment
* tls_segment
= layout
->tls_segment();
823 if (tls_segment
!= NULL
)
825 bool is_exec
= parameters
->options().output_is_executable();
826 symtab
->define_in_output_segment("_TLS_MODULE_BASE_", NULL
,
830 elfcpp::STV_HIDDEN
, 0,
832 ? Symbol::SEGMENT_END
833 : Symbol::SEGMENT_START
),
836 this->tls_base_symbol_defined_
= true;
839 // Create the reserved PLT and GOT entries for the TLS descriptor resolver.
842 Target_x86_64::reserve_tlsdesc_entries(Symbol_table
* symtab
,
845 if (this->plt_
== NULL
)
846 this->make_plt_section(symtab
, layout
);
848 if (!this->plt_
->has_tlsdesc_entry())
850 // Allocate the TLSDESC_GOT entry.
851 Output_data_got
<64, false>* got
= this->got_section(symtab
, layout
);
852 unsigned int got_offset
= got
->add_constant(0);
854 // Allocate the TLSDESC_PLT entry.
855 this->plt_
->reserve_tlsdesc_entry(got_offset
);
859 // Create a GOT entry for the TLS module index.
862 Target_x86_64::got_mod_index_entry(Symbol_table
* symtab
, Layout
* layout
,
863 Sized_relobj
<64, false>* object
)
865 if (this->got_mod_index_offset_
== -1U)
867 gold_assert(symtab
!= NULL
&& layout
!= NULL
&& object
!= NULL
);
868 Reloc_section
* rela_dyn
= this->rela_dyn_section(layout
);
869 Output_data_got
<64, false>* got
= this->got_section(symtab
, layout
);
870 unsigned int got_offset
= got
->add_constant(0);
871 rela_dyn
->add_local(object
, 0, elfcpp::R_X86_64_DTPMOD64
, got
,
873 got
->add_constant(0);
874 this->got_mod_index_offset_
= got_offset
;
876 return this->got_mod_index_offset_
;
879 // Optimize the TLS relocation type based on what we know about the
880 // symbol. IS_FINAL is true if the final address of this symbol is
881 // known at link time.
883 tls::Tls_optimization
884 Target_x86_64::optimize_tls_reloc(bool is_final
, int r_type
)
886 // If we are generating a shared library, then we can't do anything
888 if (parameters
->options().shared())
889 return tls::TLSOPT_NONE
;
893 case elfcpp::R_X86_64_TLSGD
:
894 case elfcpp::R_X86_64_GOTPC32_TLSDESC
:
895 case elfcpp::R_X86_64_TLSDESC_CALL
:
896 // These are General-Dynamic which permits fully general TLS
897 // access. Since we know that we are generating an executable,
898 // we can convert this to Initial-Exec. If we also know that
899 // this is a local symbol, we can further switch to Local-Exec.
901 return tls::TLSOPT_TO_LE
;
902 return tls::TLSOPT_TO_IE
;
904 case elfcpp::R_X86_64_TLSLD
:
905 // This is Local-Dynamic, which refers to a local symbol in the
906 // dynamic TLS block. Since we know that we generating an
907 // executable, we can switch to Local-Exec.
908 return tls::TLSOPT_TO_LE
;
910 case elfcpp::R_X86_64_DTPOFF32
:
911 case elfcpp::R_X86_64_DTPOFF64
:
912 // Another Local-Dynamic reloc.
913 return tls::TLSOPT_TO_LE
;
915 case elfcpp::R_X86_64_GOTTPOFF
:
916 // These are Initial-Exec relocs which get the thread offset
917 // from the GOT. If we know that we are linking against the
918 // local symbol, we can switch to Local-Exec, which links the
919 // thread offset into the instruction.
921 return tls::TLSOPT_TO_LE
;
922 return tls::TLSOPT_NONE
;
924 case elfcpp::R_X86_64_TPOFF32
:
925 // When we already have Local-Exec, there is nothing further we
927 return tls::TLSOPT_NONE
;
934 // Report an unsupported relocation against a local symbol.
937 Target_x86_64::Scan::unsupported_reloc_local(Sized_relobj
<64, false>* object
,
940 gold_error(_("%s: unsupported reloc %u against local symbol"),
941 object
->name().c_str(), r_type
);
944 // We are about to emit a dynamic relocation of type R_TYPE. If the
945 // dynamic linker does not support it, issue an error. The GNU linker
946 // only issues a non-PIC error for an allocated read-only section.
947 // Here we know the section is allocated, but we don't know that it is
948 // read-only. But we check for all the relocation types which the
949 // glibc dynamic linker supports, so it seems appropriate to issue an
950 // error even if the section is not read-only.
953 Target_x86_64::Scan::check_non_pic(Relobj
* object
, unsigned int r_type
)
957 // These are the relocation types supported by glibc for x86_64.
958 case elfcpp::R_X86_64_RELATIVE
:
959 case elfcpp::R_X86_64_GLOB_DAT
:
960 case elfcpp::R_X86_64_JUMP_SLOT
:
961 case elfcpp::R_X86_64_DTPMOD64
:
962 case elfcpp::R_X86_64_DTPOFF64
:
963 case elfcpp::R_X86_64_TPOFF64
:
964 case elfcpp::R_X86_64_64
:
965 case elfcpp::R_X86_64_32
:
966 case elfcpp::R_X86_64_PC32
:
967 case elfcpp::R_X86_64_COPY
:
971 // This prevents us from issuing more than one error per reloc
972 // section. But we can still wind up issuing more than one
973 // error per object file.
974 if (this->issued_non_pic_error_
)
976 object
->error(_("requires unsupported dynamic reloc; "
977 "recompile with -fPIC"));
978 this->issued_non_pic_error_
= true;
981 case elfcpp::R_X86_64_NONE
:
986 // Scan a relocation for a local symbol.
989 Target_x86_64::Scan::local(const General_options
&,
990 Symbol_table
* symtab
,
992 Target_x86_64
* target
,
993 Sized_relobj
<64, false>* object
,
994 unsigned int data_shndx
,
995 Output_section
* output_section
,
996 const elfcpp::Rela
<64, false>& reloc
,
998 const elfcpp::Sym
<64, false>& lsym
)
1002 case elfcpp::R_X86_64_NONE
:
1003 case elfcpp::R_386_GNU_VTINHERIT
:
1004 case elfcpp::R_386_GNU_VTENTRY
:
1007 case elfcpp::R_X86_64_64
:
1008 // If building a shared library (or a position-independent
1009 // executable), we need to create a dynamic relocation for this
1010 // location. The relocation applied at link time will apply the
1011 // link-time value, so we flag the location with an
1012 // R_X86_64_RELATIVE relocation so the dynamic loader can
1013 // relocate it easily.
1014 if (parameters
->options().output_is_position_independent())
1016 unsigned int r_sym
= elfcpp::elf_r_sym
<64>(reloc
.get_r_info());
1017 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
1018 rela_dyn
->add_local_relative(object
, r_sym
,
1019 elfcpp::R_X86_64_RELATIVE
,
1020 output_section
, data_shndx
,
1021 reloc
.get_r_offset(),
1022 reloc
.get_r_addend());
1026 case elfcpp::R_X86_64_32
:
1027 case elfcpp::R_X86_64_32S
:
1028 case elfcpp::R_X86_64_16
:
1029 case elfcpp::R_X86_64_8
:
1030 // If building a shared library (or a position-independent
1031 // executable), we need to create a dynamic relocation for this
1032 // location. We can't use an R_X86_64_RELATIVE relocation
1033 // because that is always a 64-bit relocation.
1034 if (parameters
->options().output_is_position_independent())
1036 this->check_non_pic(object
, r_type
);
1038 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
1039 unsigned int r_sym
= elfcpp::elf_r_sym
<64>(reloc
.get_r_info());
1040 if (lsym
.get_st_type() != elfcpp::STT_SECTION
)
1041 rela_dyn
->add_local(object
, r_sym
, r_type
, output_section
,
1042 data_shndx
, reloc
.get_r_offset(),
1043 reloc
.get_r_addend());
1046 gold_assert(lsym
.get_st_value() == 0);
1047 unsigned int shndx
= lsym
.get_st_shndx();
1049 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
,
1052 object
->error(_("section symbol %u has bad shndx %u"),
1055 rela_dyn
->add_local_section(object
, shndx
,
1056 r_type
, output_section
,
1057 data_shndx
, reloc
.get_r_offset(),
1058 reloc
.get_r_addend());
1063 case elfcpp::R_X86_64_PC64
:
1064 case elfcpp::R_X86_64_PC32
:
1065 case elfcpp::R_X86_64_PC16
:
1066 case elfcpp::R_X86_64_PC8
:
1069 case elfcpp::R_X86_64_PLT32
:
1070 // Since we know this is a local symbol, we can handle this as a
1074 case elfcpp::R_X86_64_GOTPC32
:
1075 case elfcpp::R_X86_64_GOTOFF64
:
1076 case elfcpp::R_X86_64_GOTPC64
:
1077 case elfcpp::R_X86_64_PLTOFF64
:
1078 // We need a GOT section.
1079 target
->got_section(symtab
, layout
);
1080 // For PLTOFF64, we'd normally want a PLT section, but since we
1081 // know this is a local symbol, no PLT is needed.
1084 case elfcpp::R_X86_64_GOT64
:
1085 case elfcpp::R_X86_64_GOT32
:
1086 case elfcpp::R_X86_64_GOTPCREL64
:
1087 case elfcpp::R_X86_64_GOTPCREL
:
1088 case elfcpp::R_X86_64_GOTPLT64
:
1090 // The symbol requires a GOT entry.
1091 Output_data_got
<64, false>* got
= target
->got_section(symtab
, layout
);
1092 unsigned int r_sym
= elfcpp::elf_r_sym
<64>(reloc
.get_r_info());
1093 if (got
->add_local(object
, r_sym
, GOT_TYPE_STANDARD
))
1095 // If we are generating a shared object, we need to add a
1096 // dynamic relocation for this symbol's GOT entry.
1097 if (parameters
->options().output_is_position_independent())
1099 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
1100 // R_X86_64_RELATIVE assumes a 64-bit relocation.
1101 if (r_type
!= elfcpp::R_X86_64_GOT32
)
1102 rela_dyn
->add_local_relative(
1103 object
, r_sym
, elfcpp::R_X86_64_RELATIVE
, got
,
1104 object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
), 0);
1107 this->check_non_pic(object
, r_type
);
1109 gold_assert(lsym
.get_st_type() != elfcpp::STT_SECTION
);
1110 rela_dyn
->add_local(
1111 object
, r_sym
, r_type
, got
,
1112 object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
), 0);
1116 // For GOTPLT64, we'd normally want a PLT section, but since
1117 // we know this is a local symbol, no PLT is needed.
1121 case elfcpp::R_X86_64_COPY
:
1122 case elfcpp::R_X86_64_GLOB_DAT
:
1123 case elfcpp::R_X86_64_JUMP_SLOT
:
1124 case elfcpp::R_X86_64_RELATIVE
:
1125 // These are outstanding tls relocs, which are unexpected when linking
1126 case elfcpp::R_X86_64_TPOFF64
:
1127 case elfcpp::R_X86_64_DTPMOD64
:
1128 case elfcpp::R_X86_64_TLSDESC
:
1129 gold_error(_("%s: unexpected reloc %u in object file"),
1130 object
->name().c_str(), r_type
);
1133 // These are initial tls relocs, which are expected when linking
1134 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
1135 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
1136 case elfcpp::R_X86_64_TLSDESC_CALL
:
1137 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
1138 case elfcpp::R_X86_64_DTPOFF32
:
1139 case elfcpp::R_X86_64_DTPOFF64
:
1140 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
1141 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
1143 bool output_is_shared
= parameters
->options().shared();
1144 const tls::Tls_optimization optimized_type
1145 = Target_x86_64::optimize_tls_reloc(!output_is_shared
, r_type
);
1148 case elfcpp::R_X86_64_TLSGD
: // General-dynamic
1149 if (optimized_type
== tls::TLSOPT_NONE
)
1151 // Create a pair of GOT entries for the module index and
1152 // dtv-relative offset.
1153 Output_data_got
<64, false>* got
1154 = target
->got_section(symtab
, layout
);
1155 unsigned int r_sym
= elfcpp::elf_r_sym
<64>(reloc
.get_r_info());
1156 unsigned int shndx
= lsym
.get_st_shndx();
1158 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
, &is_ordinary
);
1160 object
->error(_("local symbol %u has bad shndx %u"),
1163 got
->add_local_pair_with_rela(object
, r_sym
,
1166 target
->rela_dyn_section(layout
),
1167 elfcpp::R_X86_64_DTPMOD64
, 0);
1169 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1170 unsupported_reloc_local(object
, r_type
);
1173 case elfcpp::R_X86_64_GOTPC32_TLSDESC
:
1174 target
->define_tls_base_symbol(symtab
, layout
);
1175 if (optimized_type
== tls::TLSOPT_NONE
)
1177 // Create reserved PLT and GOT entries for the resolver.
1178 target
->reserve_tlsdesc_entries(symtab
, layout
);
1180 // Generate a double GOT entry with an R_X86_64_TLSDESC reloc.
1181 Output_data_got
<64, false>* got
1182 = target
->got_section(symtab
, layout
);
1183 unsigned int r_sym
= elfcpp::elf_r_sym
<64>(reloc
.get_r_info());
1184 unsigned int shndx
= lsym
.get_st_shndx();
1186 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
, &is_ordinary
);
1188 object
->error(_("local symbol %u has bad shndx %u"),
1191 got
->add_local_pair_with_rela(object
, r_sym
,
1194 target
->rela_dyn_section(layout
),
1195 elfcpp::R_X86_64_TLSDESC
, 0);
1197 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1198 unsupported_reloc_local(object
, r_type
);
1201 case elfcpp::R_X86_64_TLSDESC_CALL
:
1204 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
1205 if (optimized_type
== tls::TLSOPT_NONE
)
1207 // Create a GOT entry for the module index.
1208 target
->got_mod_index_entry(symtab
, layout
, object
);
1210 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1211 unsupported_reloc_local(object
, r_type
);
1214 case elfcpp::R_X86_64_DTPOFF32
:
1215 case elfcpp::R_X86_64_DTPOFF64
:
1218 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
1219 layout
->set_has_static_tls();
1220 if (optimized_type
== tls::TLSOPT_NONE
)
1222 // Create a GOT entry for the tp-relative offset.
1223 Output_data_got
<64, false>* got
1224 = target
->got_section(symtab
, layout
);
1225 unsigned int r_sym
= elfcpp::elf_r_sym
<64>(reloc
.get_r_info());
1226 got
->add_local_with_rela(object
, r_sym
, GOT_TYPE_TLS_OFFSET
,
1227 target
->rela_dyn_section(layout
),
1228 elfcpp::R_X86_64_TPOFF64
);
1230 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1231 unsupported_reloc_local(object
, r_type
);
1234 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
1235 layout
->set_has_static_tls();
1236 if (output_is_shared
)
1237 unsupported_reloc_local(object
, r_type
);
1246 case elfcpp::R_X86_64_SIZE32
:
1247 case elfcpp::R_X86_64_SIZE64
:
1249 gold_error(_("%s: unsupported reloc %u against local symbol"),
1250 object
->name().c_str(), r_type
);
1256 // Report an unsupported relocation against a global symbol.
1259 Target_x86_64::Scan::unsupported_reloc_global(Sized_relobj
<64, false>* object
,
1260 unsigned int r_type
,
1263 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
1264 object
->name().c_str(), r_type
, gsym
->demangled_name().c_str());
1267 // Scan a relocation for a global symbol.
1270 Target_x86_64::Scan::global(const General_options
&,
1271 Symbol_table
* symtab
,
1273 Target_x86_64
* target
,
1274 Sized_relobj
<64, false>* object
,
1275 unsigned int data_shndx
,
1276 Output_section
* output_section
,
1277 const elfcpp::Rela
<64, false>& reloc
,
1278 unsigned int r_type
,
1283 case elfcpp::R_X86_64_NONE
:
1284 case elfcpp::R_386_GNU_VTINHERIT
:
1285 case elfcpp::R_386_GNU_VTENTRY
:
1288 case elfcpp::R_X86_64_64
:
1289 case elfcpp::R_X86_64_32
:
1290 case elfcpp::R_X86_64_32S
:
1291 case elfcpp::R_X86_64_16
:
1292 case elfcpp::R_X86_64_8
:
1294 // Make a PLT entry if necessary.
1295 if (gsym
->needs_plt_entry())
1297 target
->make_plt_entry(symtab
, layout
, gsym
);
1298 // Since this is not a PC-relative relocation, we may be
1299 // taking the address of a function. In that case we need to
1300 // set the entry in the dynamic symbol table to the address of
1302 if (gsym
->is_from_dynobj() && !parameters
->options().shared())
1303 gsym
->set_needs_dynsym_value();
1305 // Make a dynamic relocation if necessary.
1306 if (gsym
->needs_dynamic_reloc(Symbol::ABSOLUTE_REF
))
1308 if (target
->may_need_copy_reloc(gsym
))
1310 target
->copy_reloc(symtab
, layout
, object
,
1311 data_shndx
, output_section
, gsym
, reloc
);
1313 else if (r_type
== elfcpp::R_X86_64_64
1314 && gsym
->can_use_relative_reloc(false))
1316 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
1317 rela_dyn
->add_global_relative(gsym
, elfcpp::R_X86_64_RELATIVE
,
1318 output_section
, object
,
1319 data_shndx
, reloc
.get_r_offset(),
1320 reloc
.get_r_addend());
1324 this->check_non_pic(object
, r_type
);
1325 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
1326 rela_dyn
->add_global(gsym
, r_type
, output_section
, object
,
1327 data_shndx
, reloc
.get_r_offset(),
1328 reloc
.get_r_addend());
1334 case elfcpp::R_X86_64_PC64
:
1335 case elfcpp::R_X86_64_PC32
:
1336 case elfcpp::R_X86_64_PC16
:
1337 case elfcpp::R_X86_64_PC8
:
1339 // Make a PLT entry if necessary.
1340 if (gsym
->needs_plt_entry())
1341 target
->make_plt_entry(symtab
, layout
, gsym
);
1342 // Make a dynamic relocation if necessary.
1343 int flags
= Symbol::NON_PIC_REF
;
1344 if (gsym
->type() == elfcpp::STT_FUNC
)
1345 flags
|= Symbol::FUNCTION_CALL
;
1346 if (gsym
->needs_dynamic_reloc(flags
))
1348 if (target
->may_need_copy_reloc(gsym
))
1350 target
->copy_reloc(symtab
, layout
, object
,
1351 data_shndx
, output_section
, gsym
, reloc
);
1355 this->check_non_pic(object
, r_type
);
1356 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
1357 rela_dyn
->add_global(gsym
, r_type
, output_section
, object
,
1358 data_shndx
, reloc
.get_r_offset(),
1359 reloc
.get_r_addend());
1365 case elfcpp::R_X86_64_GOT64
:
1366 case elfcpp::R_X86_64_GOT32
:
1367 case elfcpp::R_X86_64_GOTPCREL64
:
1368 case elfcpp::R_X86_64_GOTPCREL
:
1369 case elfcpp::R_X86_64_GOTPLT64
:
1371 // The symbol requires a GOT entry.
1372 Output_data_got
<64, false>* got
= target
->got_section(symtab
, layout
);
1373 if (gsym
->final_value_is_known())
1374 got
->add_global(gsym
, GOT_TYPE_STANDARD
);
1377 // If this symbol is not fully resolved, we need to add a
1378 // dynamic relocation for it.
1379 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
1380 if (gsym
->is_from_dynobj()
1381 || gsym
->is_undefined()
1382 || gsym
->is_preemptible())
1383 got
->add_global_with_rela(gsym
, GOT_TYPE_STANDARD
, rela_dyn
,
1384 elfcpp::R_X86_64_GLOB_DAT
);
1387 if (got
->add_global(gsym
, GOT_TYPE_STANDARD
))
1388 rela_dyn
->add_global_relative(
1389 gsym
, elfcpp::R_X86_64_RELATIVE
, got
,
1390 gsym
->got_offset(GOT_TYPE_STANDARD
), 0);
1393 // For GOTPLT64, we also need a PLT entry (but only if the
1394 // symbol is not fully resolved).
1395 if (r_type
== elfcpp::R_X86_64_GOTPLT64
1396 && !gsym
->final_value_is_known())
1397 target
->make_plt_entry(symtab
, layout
, gsym
);
1401 case elfcpp::R_X86_64_PLT32
:
1402 // If the symbol is fully resolved, this is just a PC32 reloc.
1403 // Otherwise we need a PLT entry.
1404 if (gsym
->final_value_is_known())
1406 // If building a shared library, we can also skip the PLT entry
1407 // if the symbol is defined in the output file and is protected
1409 if (gsym
->is_defined()
1410 && !gsym
->is_from_dynobj()
1411 && !gsym
->is_preemptible())
1413 target
->make_plt_entry(symtab
, layout
, gsym
);
1416 case elfcpp::R_X86_64_GOTPC32
:
1417 case elfcpp::R_X86_64_GOTOFF64
:
1418 case elfcpp::R_X86_64_GOTPC64
:
1419 case elfcpp::R_X86_64_PLTOFF64
:
1420 // We need a GOT section.
1421 target
->got_section(symtab
, layout
);
1422 // For PLTOFF64, we also need a PLT entry (but only if the
1423 // symbol is not fully resolved).
1424 if (r_type
== elfcpp::R_X86_64_PLTOFF64
1425 && !gsym
->final_value_is_known())
1426 target
->make_plt_entry(symtab
, layout
, gsym
);
1429 case elfcpp::R_X86_64_COPY
:
1430 case elfcpp::R_X86_64_GLOB_DAT
:
1431 case elfcpp::R_X86_64_JUMP_SLOT
:
1432 case elfcpp::R_X86_64_RELATIVE
:
1433 // These are outstanding tls relocs, which are unexpected when linking
1434 case elfcpp::R_X86_64_TPOFF64
:
1435 case elfcpp::R_X86_64_DTPMOD64
:
1436 case elfcpp::R_X86_64_TLSDESC
:
1437 gold_error(_("%s: unexpected reloc %u in object file"),
1438 object
->name().c_str(), r_type
);
1441 // These are initial tls relocs, which are expected for global()
1442 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
1443 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
1444 case elfcpp::R_X86_64_TLSDESC_CALL
:
1445 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
1446 case elfcpp::R_X86_64_DTPOFF32
:
1447 case elfcpp::R_X86_64_DTPOFF64
:
1448 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
1449 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
1451 const bool is_final
= gsym
->final_value_is_known();
1452 const tls::Tls_optimization optimized_type
1453 = Target_x86_64::optimize_tls_reloc(is_final
, r_type
);
1456 case elfcpp::R_X86_64_TLSGD
: // General-dynamic
1457 if (optimized_type
== tls::TLSOPT_NONE
)
1459 // Create a pair of GOT entries for the module index and
1460 // dtv-relative offset.
1461 Output_data_got
<64, false>* got
1462 = target
->got_section(symtab
, layout
);
1463 got
->add_global_pair_with_rela(gsym
, GOT_TYPE_TLS_PAIR
,
1464 target
->rela_dyn_section(layout
),
1465 elfcpp::R_X86_64_DTPMOD64
,
1466 elfcpp::R_X86_64_DTPOFF64
);
1468 else if (optimized_type
== tls::TLSOPT_TO_IE
)
1470 // Create a GOT entry for the tp-relative offset.
1471 Output_data_got
<64, false>* got
1472 = target
->got_section(symtab
, layout
);
1473 got
->add_global_with_rela(gsym
, GOT_TYPE_TLS_OFFSET
,
1474 target
->rela_dyn_section(layout
),
1475 elfcpp::R_X86_64_TPOFF64
);
1477 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1478 unsupported_reloc_global(object
, r_type
, gsym
);
1481 case elfcpp::R_X86_64_GOTPC32_TLSDESC
:
1482 target
->define_tls_base_symbol(symtab
, layout
);
1483 if (optimized_type
== tls::TLSOPT_NONE
)
1485 // Create reserved PLT and GOT entries for the resolver.
1486 target
->reserve_tlsdesc_entries(symtab
, layout
);
1488 // Create a double GOT entry with an R_X86_64_TLSDESC reloc.
1489 Output_data_got
<64, false>* got
1490 = target
->got_section(symtab
, layout
);
1491 got
->add_global_pair_with_rela(gsym
, GOT_TYPE_TLS_DESC
,
1492 target
->rela_dyn_section(layout
),
1493 elfcpp::R_X86_64_TLSDESC
, 0);
1495 else if (optimized_type
== tls::TLSOPT_TO_IE
)
1497 // Create a GOT entry for the tp-relative offset.
1498 Output_data_got
<64, false>* got
1499 = target
->got_section(symtab
, layout
);
1500 got
->add_global_with_rela(gsym
, GOT_TYPE_TLS_OFFSET
,
1501 target
->rela_dyn_section(layout
),
1502 elfcpp::R_X86_64_TPOFF64
);
1504 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1505 unsupported_reloc_global(object
, r_type
, gsym
);
1508 case elfcpp::R_X86_64_TLSDESC_CALL
:
1511 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
1512 if (optimized_type
== tls::TLSOPT_NONE
)
1514 // Create a GOT entry for the module index.
1515 target
->got_mod_index_entry(symtab
, layout
, object
);
1517 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1518 unsupported_reloc_global(object
, r_type
, gsym
);
1521 case elfcpp::R_X86_64_DTPOFF32
:
1522 case elfcpp::R_X86_64_DTPOFF64
:
1525 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
1526 layout
->set_has_static_tls();
1527 if (optimized_type
== tls::TLSOPT_NONE
)
1529 // Create a GOT entry for the tp-relative offset.
1530 Output_data_got
<64, false>* got
1531 = target
->got_section(symtab
, layout
);
1532 got
->add_global_with_rela(gsym
, GOT_TYPE_TLS_OFFSET
,
1533 target
->rela_dyn_section(layout
),
1534 elfcpp::R_X86_64_TPOFF64
);
1536 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1537 unsupported_reloc_global(object
, r_type
, gsym
);
1540 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
1541 layout
->set_has_static_tls();
1542 if (parameters
->options().shared())
1543 unsupported_reloc_local(object
, r_type
);
1552 case elfcpp::R_X86_64_SIZE32
:
1553 case elfcpp::R_X86_64_SIZE64
:
1555 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
1556 object
->name().c_str(), r_type
,
1557 gsym
->demangled_name().c_str());
1563 Target_x86_64::gc_process_relocs(const General_options
& options
,
1564 Symbol_table
* symtab
,
1566 Sized_relobj
<64, false>* object
,
1567 unsigned int data_shndx
,
1568 unsigned int sh_type
,
1569 const unsigned char* prelocs
,
1571 Output_section
* output_section
,
1572 bool needs_special_offset_handling
,
1573 size_t local_symbol_count
,
1574 const unsigned char* plocal_symbols
)
1577 if (sh_type
== elfcpp::SHT_REL
)
1582 gold::gc_process_relocs
<64, false, Target_x86_64
, elfcpp::SHT_RELA
,
1583 Target_x86_64::Scan
>(
1593 needs_special_offset_handling
,
1598 // Scan relocations for a section.
1601 Target_x86_64::scan_relocs(const General_options
& options
,
1602 Symbol_table
* symtab
,
1604 Sized_relobj
<64, false>* object
,
1605 unsigned int data_shndx
,
1606 unsigned int sh_type
,
1607 const unsigned char* prelocs
,
1609 Output_section
* output_section
,
1610 bool needs_special_offset_handling
,
1611 size_t local_symbol_count
,
1612 const unsigned char* plocal_symbols
)
1614 if (sh_type
== elfcpp::SHT_REL
)
1616 gold_error(_("%s: unsupported REL reloc section"),
1617 object
->name().c_str());
1621 gold::scan_relocs
<64, false, Target_x86_64
, elfcpp::SHT_RELA
,
1622 Target_x86_64::Scan
>(
1632 needs_special_offset_handling
,
1637 // Finalize the sections.
1640 Target_x86_64::do_finalize_sections(Layout
* layout
)
1642 // Fill in some more dynamic tags.
1643 Output_data_dynamic
* const odyn
= layout
->dynamic_data();
1646 if (this->got_plt_
!= NULL
)
1647 odyn
->add_section_address(elfcpp::DT_PLTGOT
, this->got_plt_
);
1649 if (this->plt_
!= NULL
)
1651 const Output_data
* od
= this->plt_
->rel_plt();
1652 odyn
->add_section_size(elfcpp::DT_PLTRELSZ
, od
);
1653 odyn
->add_section_address(elfcpp::DT_JMPREL
, od
);
1654 odyn
->add_constant(elfcpp::DT_PLTREL
, elfcpp::DT_RELA
);
1655 if (this->plt_
->has_tlsdesc_entry())
1657 unsigned int plt_offset
= this->plt_
->get_tlsdesc_plt_offset();
1658 unsigned int got_offset
= this->plt_
->get_tlsdesc_got_offset();
1659 this->got_
->finalize_data_size();
1660 odyn
->add_section_plus_offset(elfcpp::DT_TLSDESC_PLT
,
1661 this->plt_
, plt_offset
);
1662 odyn
->add_section_plus_offset(elfcpp::DT_TLSDESC_GOT
,
1663 this->got_
, got_offset
);
1667 if (this->rela_dyn_
!= NULL
)
1669 const Output_data
* od
= this->rela_dyn_
;
1670 odyn
->add_section_address(elfcpp::DT_RELA
, od
);
1671 odyn
->add_section_size(elfcpp::DT_RELASZ
, od
);
1672 odyn
->add_constant(elfcpp::DT_RELAENT
,
1673 elfcpp::Elf_sizes
<64>::rela_size
);
1676 if (!parameters
->options().shared())
1678 // The value of the DT_DEBUG tag is filled in by the dynamic
1679 // linker at run time, and used by the debugger.
1680 odyn
->add_constant(elfcpp::DT_DEBUG
, 0);
1684 // Emit any relocs we saved in an attempt to avoid generating COPY
1686 if (this->copy_relocs_
.any_saved_relocs())
1687 this->copy_relocs_
.emit(this->rela_dyn_section(layout
));
1690 // Perform a relocation.
1693 Target_x86_64::Relocate::relocate(const Relocate_info
<64, false>* relinfo
,
1694 Target_x86_64
* target
,
1696 const elfcpp::Rela
<64, false>& rela
,
1697 unsigned int r_type
,
1698 const Sized_symbol
<64>* gsym
,
1699 const Symbol_value
<64>* psymval
,
1700 unsigned char* view
,
1701 elfcpp::Elf_types
<64>::Elf_Addr address
,
1702 section_size_type view_size
)
1704 if (this->skip_call_tls_get_addr_
)
1706 if (r_type
!= elfcpp::R_X86_64_PLT32
1708 || strcmp(gsym
->name(), "__tls_get_addr") != 0)
1710 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
1711 _("missing expected TLS relocation"));
1715 this->skip_call_tls_get_addr_
= false;
1720 // Pick the value to use for symbols defined in shared objects.
1721 Symbol_value
<64> symval
;
1723 && gsym
->use_plt_offset(r_type
== elfcpp::R_X86_64_PC64
1724 || r_type
== elfcpp::R_X86_64_PC32
1725 || r_type
== elfcpp::R_X86_64_PC16
1726 || r_type
== elfcpp::R_X86_64_PC8
))
1728 symval
.set_output_value(target
->plt_section()->address()
1729 + gsym
->plt_offset());
1733 const Sized_relobj
<64, false>* object
= relinfo
->object
;
1734 const elfcpp::Elf_Xword addend
= rela
.get_r_addend();
1736 // Get the GOT offset if needed.
1737 // The GOT pointer points to the end of the GOT section.
1738 // We need to subtract the size of the GOT section to get
1739 // the actual offset to use in the relocation.
1740 bool have_got_offset
= false;
1741 unsigned int got_offset
= 0;
1744 case elfcpp::R_X86_64_GOT32
:
1745 case elfcpp::R_X86_64_GOT64
:
1746 case elfcpp::R_X86_64_GOTPLT64
:
1747 case elfcpp::R_X86_64_GOTPCREL
:
1748 case elfcpp::R_X86_64_GOTPCREL64
:
1751 gold_assert(gsym
->has_got_offset(GOT_TYPE_STANDARD
));
1752 got_offset
= gsym
->got_offset(GOT_TYPE_STANDARD
) - target
->got_size();
1756 unsigned int r_sym
= elfcpp::elf_r_sym
<64>(rela
.get_r_info());
1757 gold_assert(object
->local_has_got_offset(r_sym
, GOT_TYPE_STANDARD
));
1758 got_offset
= (object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
)
1759 - target
->got_size());
1761 have_got_offset
= true;
1770 case elfcpp::R_X86_64_NONE
:
1771 case elfcpp::R_386_GNU_VTINHERIT
:
1772 case elfcpp::R_386_GNU_VTENTRY
:
1775 case elfcpp::R_X86_64_64
:
1776 Relocate_functions
<64, false>::rela64(view
, object
, psymval
, addend
);
1779 case elfcpp::R_X86_64_PC64
:
1780 Relocate_functions
<64, false>::pcrela64(view
, object
, psymval
, addend
,
1784 case elfcpp::R_X86_64_32
:
1785 // FIXME: we need to verify that value + addend fits into 32 bits:
1786 // uint64_t x = value + addend;
1787 // x == static_cast<uint64_t>(static_cast<uint32_t>(x))
1788 // Likewise for other <=32-bit relocations (but see R_X86_64_32S).
1789 Relocate_functions
<64, false>::rela32(view
, object
, psymval
, addend
);
1792 case elfcpp::R_X86_64_32S
:
1793 // FIXME: we need to verify that value + addend fits into 32 bits:
1794 // int64_t x = value + addend; // note this quantity is signed!
1795 // x == static_cast<int64_t>(static_cast<int32_t>(x))
1796 Relocate_functions
<64, false>::rela32(view
, object
, psymval
, addend
);
1799 case elfcpp::R_X86_64_PC32
:
1800 Relocate_functions
<64, false>::pcrela32(view
, object
, psymval
, addend
,
1804 case elfcpp::R_X86_64_16
:
1805 Relocate_functions
<64, false>::rela16(view
, object
, psymval
, addend
);
1808 case elfcpp::R_X86_64_PC16
:
1809 Relocate_functions
<64, false>::pcrela16(view
, object
, psymval
, addend
,
1813 case elfcpp::R_X86_64_8
:
1814 Relocate_functions
<64, false>::rela8(view
, object
, psymval
, addend
);
1817 case elfcpp::R_X86_64_PC8
:
1818 Relocate_functions
<64, false>::pcrela8(view
, object
, psymval
, addend
,
1822 case elfcpp::R_X86_64_PLT32
:
1823 gold_assert(gsym
== NULL
1824 || gsym
->has_plt_offset()
1825 || gsym
->final_value_is_known()
1826 || (gsym
->is_defined()
1827 && !gsym
->is_from_dynobj()
1828 && !gsym
->is_preemptible()));
1829 // Note: while this code looks the same as for R_X86_64_PC32, it
1830 // behaves differently because psymval was set to point to
1831 // the PLT entry, rather than the symbol, in Scan::global().
1832 Relocate_functions
<64, false>::pcrela32(view
, object
, psymval
, addend
,
1836 case elfcpp::R_X86_64_PLTOFF64
:
1839 gold_assert(gsym
->has_plt_offset()
1840 || gsym
->final_value_is_known());
1841 elfcpp::Elf_types
<64>::Elf_Addr got_address
;
1842 got_address
= target
->got_section(NULL
, NULL
)->address();
1843 Relocate_functions
<64, false>::rela64(view
, object
, psymval
,
1844 addend
- got_address
);
1847 case elfcpp::R_X86_64_GOT32
:
1848 gold_assert(have_got_offset
);
1849 Relocate_functions
<64, false>::rela32(view
, got_offset
, addend
);
1852 case elfcpp::R_X86_64_GOTPC32
:
1855 elfcpp::Elf_types
<64>::Elf_Addr value
;
1856 value
= target
->got_plt_section()->address();
1857 Relocate_functions
<64, false>::pcrela32(view
, value
, addend
, address
);
1861 case elfcpp::R_X86_64_GOT64
:
1862 // The ABI doc says "Like GOT64, but indicates a PLT entry is needed."
1863 // Since we always add a PLT entry, this is equivalent.
1864 case elfcpp::R_X86_64_GOTPLT64
:
1865 gold_assert(have_got_offset
);
1866 Relocate_functions
<64, false>::rela64(view
, got_offset
, addend
);
1869 case elfcpp::R_X86_64_GOTPC64
:
1872 elfcpp::Elf_types
<64>::Elf_Addr value
;
1873 value
= target
->got_plt_section()->address();
1874 Relocate_functions
<64, false>::pcrela64(view
, value
, addend
, address
);
1878 case elfcpp::R_X86_64_GOTOFF64
:
1880 elfcpp::Elf_types
<64>::Elf_Addr value
;
1881 value
= (psymval
->value(object
, 0)
1882 - target
->got_plt_section()->address());
1883 Relocate_functions
<64, false>::rela64(view
, value
, addend
);
1887 case elfcpp::R_X86_64_GOTPCREL
:
1889 gold_assert(have_got_offset
);
1890 elfcpp::Elf_types
<64>::Elf_Addr value
;
1891 value
= target
->got_plt_section()->address() + got_offset
;
1892 Relocate_functions
<64, false>::pcrela32(view
, value
, addend
, address
);
1896 case elfcpp::R_X86_64_GOTPCREL64
:
1898 gold_assert(have_got_offset
);
1899 elfcpp::Elf_types
<64>::Elf_Addr value
;
1900 value
= target
->got_plt_section()->address() + got_offset
;
1901 Relocate_functions
<64, false>::pcrela64(view
, value
, addend
, address
);
1905 case elfcpp::R_X86_64_COPY
:
1906 case elfcpp::R_X86_64_GLOB_DAT
:
1907 case elfcpp::R_X86_64_JUMP_SLOT
:
1908 case elfcpp::R_X86_64_RELATIVE
:
1909 // These are outstanding tls relocs, which are unexpected when linking
1910 case elfcpp::R_X86_64_TPOFF64
:
1911 case elfcpp::R_X86_64_DTPMOD64
:
1912 case elfcpp::R_X86_64_TLSDESC
:
1913 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
1914 _("unexpected reloc %u in object file"),
1918 // These are initial tls relocs, which are expected when linking
1919 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
1920 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
1921 case elfcpp::R_X86_64_TLSDESC_CALL
:
1922 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
1923 case elfcpp::R_X86_64_DTPOFF32
:
1924 case elfcpp::R_X86_64_DTPOFF64
:
1925 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
1926 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
1927 this->relocate_tls(relinfo
, target
, relnum
, rela
, r_type
, gsym
, psymval
,
1928 view
, address
, view_size
);
1931 case elfcpp::R_X86_64_SIZE32
:
1932 case elfcpp::R_X86_64_SIZE64
:
1934 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
1935 _("unsupported reloc %u"),
1943 // Perform a TLS relocation.
1946 Target_x86_64::Relocate::relocate_tls(const Relocate_info
<64, false>* relinfo
,
1947 Target_x86_64
* target
,
1949 const elfcpp::Rela
<64, false>& rela
,
1950 unsigned int r_type
,
1951 const Sized_symbol
<64>* gsym
,
1952 const Symbol_value
<64>* psymval
,
1953 unsigned char* view
,
1954 elfcpp::Elf_types
<64>::Elf_Addr address
,
1955 section_size_type view_size
)
1957 Output_segment
* tls_segment
= relinfo
->layout
->tls_segment();
1959 const Sized_relobj
<64, false>* object
= relinfo
->object
;
1960 const elfcpp::Elf_Xword addend
= rela
.get_r_addend();
1962 elfcpp::Elf_types
<64>::Elf_Addr value
= psymval
->value(relinfo
->object
, 0);
1964 const bool is_final
= (gsym
== NULL
1965 ? !parameters
->options().output_is_position_independent()
1966 : gsym
->final_value_is_known());
1967 const tls::Tls_optimization optimized_type
1968 = Target_x86_64::optimize_tls_reloc(is_final
, r_type
);
1971 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
1972 this->saw_tls_block_reloc_
= true;
1973 if (optimized_type
== tls::TLSOPT_TO_LE
)
1975 gold_assert(tls_segment
!= NULL
);
1976 this->tls_gd_to_le(relinfo
, relnum
, tls_segment
,
1977 rela
, r_type
, value
, view
,
1983 unsigned int got_type
= (optimized_type
== tls::TLSOPT_TO_IE
1984 ? GOT_TYPE_TLS_OFFSET
1985 : GOT_TYPE_TLS_PAIR
);
1986 unsigned int got_offset
;
1989 gold_assert(gsym
->has_got_offset(got_type
));
1990 got_offset
= gsym
->got_offset(got_type
) - target
->got_size();
1994 unsigned int r_sym
= elfcpp::elf_r_sym
<64>(rela
.get_r_info());
1995 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
1996 got_offset
= (object
->local_got_offset(r_sym
, got_type
)
1997 - target
->got_size());
1999 if (optimized_type
== tls::TLSOPT_TO_IE
)
2001 gold_assert(tls_segment
!= NULL
);
2002 value
= target
->got_plt_section()->address() + got_offset
;
2003 this->tls_gd_to_ie(relinfo
, relnum
, tls_segment
, rela
, r_type
,
2004 value
, view
, address
, view_size
);
2007 else if (optimized_type
== tls::TLSOPT_NONE
)
2009 // Relocate the field with the offset of the pair of GOT
2011 value
= target
->got_plt_section()->address() + got_offset
;
2012 Relocate_functions
<64, false>::pcrela32(view
, value
, addend
,
2017 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
2018 _("unsupported reloc %u"), r_type
);
2021 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
2022 case elfcpp::R_X86_64_TLSDESC_CALL
:
2023 this->saw_tls_block_reloc_
= true;
2024 if (optimized_type
== tls::TLSOPT_TO_LE
)
2026 gold_assert(tls_segment
!= NULL
);
2027 this->tls_desc_gd_to_le(relinfo
, relnum
, tls_segment
,
2028 rela
, r_type
, value
, view
,
2034 unsigned int got_type
= (optimized_type
== tls::TLSOPT_TO_IE
2035 ? GOT_TYPE_TLS_OFFSET
2036 : GOT_TYPE_TLS_DESC
);
2037 unsigned int got_offset
;
2040 gold_assert(gsym
->has_got_offset(got_type
));
2041 got_offset
= gsym
->got_offset(got_type
) - target
->got_size();
2045 unsigned int r_sym
= elfcpp::elf_r_sym
<64>(rela
.get_r_info());
2046 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
2047 got_offset
= (object
->local_got_offset(r_sym
, got_type
)
2048 - target
->got_size());
2050 if (optimized_type
== tls::TLSOPT_TO_IE
)
2052 gold_assert(tls_segment
!= NULL
);
2053 value
= target
->got_plt_section()->address() + got_offset
;
2054 this->tls_desc_gd_to_ie(relinfo
, relnum
, tls_segment
,
2055 rela
, r_type
, value
, view
, address
,
2059 else if (optimized_type
== tls::TLSOPT_NONE
)
2061 if (r_type
== elfcpp::R_X86_64_GOTPC32_TLSDESC
)
2063 // Relocate the field with the offset of the pair of GOT
2065 value
= target
->got_plt_section()->address() + got_offset
;
2066 Relocate_functions
<64, false>::pcrela32(view
, value
, addend
,
2072 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
2073 _("unsupported reloc %u"), r_type
);
2076 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
2077 this->saw_tls_block_reloc_
= true;
2078 if (optimized_type
== tls::TLSOPT_TO_LE
)
2080 gold_assert(tls_segment
!= NULL
);
2081 this->tls_ld_to_le(relinfo
, relnum
, tls_segment
, rela
, r_type
,
2082 value
, view
, view_size
);
2085 else if (optimized_type
== tls::TLSOPT_NONE
)
2087 // Relocate the field with the offset of the GOT entry for
2088 // the module index.
2089 unsigned int got_offset
;
2090 got_offset
= (target
->got_mod_index_entry(NULL
, NULL
, NULL
)
2091 - target
->got_size());
2092 value
= target
->got_plt_section()->address() + got_offset
;
2093 Relocate_functions
<64, false>::pcrela32(view
, value
, addend
,
2097 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
2098 _("unsupported reloc %u"), r_type
);
2101 case elfcpp::R_X86_64_DTPOFF32
:
2102 gold_assert(tls_segment
!= NULL
);
2103 if (optimized_type
== tls::TLSOPT_TO_LE
)
2105 // This relocation type is used in debugging information.
2106 // In that case we need to not optimize the value. If we
2107 // haven't seen a TLSLD reloc, then we assume we should not
2108 // optimize this reloc.
2109 if (this->saw_tls_block_reloc_
)
2110 value
-= tls_segment
->memsz();
2112 Relocate_functions
<64, false>::rela32(view
, value
, addend
);
2115 case elfcpp::R_X86_64_DTPOFF64
:
2116 gold_assert(tls_segment
!= NULL
);
2117 if (optimized_type
== tls::TLSOPT_TO_LE
)
2119 // See R_X86_64_DTPOFF32, just above, for why we test this.
2120 if (this->saw_tls_block_reloc_
)
2121 value
-= tls_segment
->memsz();
2123 Relocate_functions
<64, false>::rela64(view
, value
, addend
);
2126 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
2127 if (optimized_type
== tls::TLSOPT_TO_LE
)
2129 gold_assert(tls_segment
!= NULL
);
2130 Target_x86_64::Relocate::tls_ie_to_le(relinfo
, relnum
, tls_segment
,
2131 rela
, r_type
, value
, view
,
2135 else if (optimized_type
== tls::TLSOPT_NONE
)
2137 // Relocate the field with the offset of the GOT entry for
2138 // the tp-relative offset of the symbol.
2139 unsigned int got_offset
;
2142 gold_assert(gsym
->has_got_offset(GOT_TYPE_TLS_OFFSET
));
2143 got_offset
= (gsym
->got_offset(GOT_TYPE_TLS_OFFSET
)
2144 - target
->got_size());
2148 unsigned int r_sym
= elfcpp::elf_r_sym
<64>(rela
.get_r_info());
2149 gold_assert(object
->local_has_got_offset(r_sym
,
2150 GOT_TYPE_TLS_OFFSET
));
2151 got_offset
= (object
->local_got_offset(r_sym
, GOT_TYPE_TLS_OFFSET
)
2152 - target
->got_size());
2154 value
= target
->got_plt_section()->address() + got_offset
;
2155 Relocate_functions
<64, false>::pcrela32(view
, value
, addend
, address
);
2158 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
2159 _("unsupported reloc type %u"),
2163 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
2164 value
-= tls_segment
->memsz();
2165 Relocate_functions
<64, false>::rela32(view
, value
, addend
);
2170 // Do a relocation in which we convert a TLS General-Dynamic to an
2174 Target_x86_64::Relocate::tls_gd_to_ie(const Relocate_info
<64, false>* relinfo
,
2177 const elfcpp::Rela
<64, false>& rela
,
2179 elfcpp::Elf_types
<64>::Elf_Addr value
,
2180 unsigned char* view
,
2181 elfcpp::Elf_types
<64>::Elf_Addr address
,
2182 section_size_type view_size
)
2184 // .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
2185 // .word 0x6666; rex64; call __tls_get_addr
2186 // ==> movq %fs:0,%rax; addq x@gottpoff(%rip),%rax
2188 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -4);
2189 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 12);
2191 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
2192 (memcmp(view
- 4, "\x66\x48\x8d\x3d", 4) == 0));
2193 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
2194 (memcmp(view
+ 4, "\x66\x66\x48\xe8", 4) == 0));
2196 memcpy(view
- 4, "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x03\x05\0\0\0\0", 16);
2198 const elfcpp::Elf_Xword addend
= rela
.get_r_addend();
2199 Relocate_functions
<64, false>::pcrela32(view
+ 8, value
, addend
- 8, address
);
2201 // The next reloc should be a PLT32 reloc against __tls_get_addr.
2203 this->skip_call_tls_get_addr_
= true;
2206 // Do a relocation in which we convert a TLS General-Dynamic to a
2210 Target_x86_64::Relocate::tls_gd_to_le(const Relocate_info
<64, false>* relinfo
,
2212 Output_segment
* tls_segment
,
2213 const elfcpp::Rela
<64, false>& rela
,
2215 elfcpp::Elf_types
<64>::Elf_Addr value
,
2216 unsigned char* view
,
2217 section_size_type view_size
)
2219 // .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
2220 // .word 0x6666; rex64; call __tls_get_addr
2221 // ==> movq %fs:0,%rax; leaq x@tpoff(%rax),%rax
2223 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -4);
2224 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 12);
2226 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
2227 (memcmp(view
- 4, "\x66\x48\x8d\x3d", 4) == 0));
2228 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
2229 (memcmp(view
+ 4, "\x66\x66\x48\xe8", 4) == 0));
2231 memcpy(view
- 4, "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0\0", 16);
2233 value
-= tls_segment
->memsz();
2234 Relocate_functions
<64, false>::rela32(view
+ 8, value
, 0);
2236 // The next reloc should be a PLT32 reloc against __tls_get_addr.
2238 this->skip_call_tls_get_addr_
= true;
2241 // Do a TLSDESC-style General-Dynamic to Initial-Exec transition.
2244 Target_x86_64::Relocate::tls_desc_gd_to_ie(
2245 const Relocate_info
<64, false>* relinfo
,
2248 const elfcpp::Rela
<64, false>& rela
,
2249 unsigned int r_type
,
2250 elfcpp::Elf_types
<64>::Elf_Addr value
,
2251 unsigned char* view
,
2252 elfcpp::Elf_types
<64>::Elf_Addr address
,
2253 section_size_type view_size
)
2255 if (r_type
== elfcpp::R_X86_64_GOTPC32_TLSDESC
)
2257 // leaq foo@tlsdesc(%rip), %rax
2258 // ==> movq foo@gottpoff(%rip), %rax
2259 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -3);
2260 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 4);
2261 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
2262 view
[-3] == 0x48 && view
[-2] == 0x8d && view
[-1] == 0x05);
2264 const elfcpp::Elf_Xword addend
= rela
.get_r_addend();
2265 Relocate_functions
<64, false>::pcrela32(view
, value
, addend
, address
);
2269 // call *foo@tlscall(%rax)
2271 gold_assert(r_type
== elfcpp::R_X86_64_TLSDESC_CALL
);
2272 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 2);
2273 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
2274 view
[0] == 0xff && view
[1] == 0x10);
2280 // Do a TLSDESC-style General-Dynamic to Local-Exec transition.
2283 Target_x86_64::Relocate::tls_desc_gd_to_le(
2284 const Relocate_info
<64, false>* relinfo
,
2286 Output_segment
* tls_segment
,
2287 const elfcpp::Rela
<64, false>& rela
,
2288 unsigned int r_type
,
2289 elfcpp::Elf_types
<64>::Elf_Addr value
,
2290 unsigned char* view
,
2291 section_size_type view_size
)
2293 if (r_type
== elfcpp::R_X86_64_GOTPC32_TLSDESC
)
2295 // leaq foo@tlsdesc(%rip), %rax
2296 // ==> movq foo@tpoff, %rax
2297 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -3);
2298 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 4);
2299 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
2300 view
[-3] == 0x48 && view
[-2] == 0x8d && view
[-1] == 0x05);
2303 value
-= tls_segment
->memsz();
2304 Relocate_functions
<64, false>::rela32(view
, value
, 0);
2308 // call *foo@tlscall(%rax)
2310 gold_assert(r_type
== elfcpp::R_X86_64_TLSDESC_CALL
);
2311 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 2);
2312 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
2313 view
[0] == 0xff && view
[1] == 0x10);
2320 Target_x86_64::Relocate::tls_ld_to_le(const Relocate_info
<64, false>* relinfo
,
2323 const elfcpp::Rela
<64, false>& rela
,
2325 elfcpp::Elf_types
<64>::Elf_Addr
,
2326 unsigned char* view
,
2327 section_size_type view_size
)
2329 // leaq foo@tlsld(%rip),%rdi; call __tls_get_addr@plt;
2330 // ... leq foo@dtpoff(%rax),%reg
2331 // ==> .word 0x6666; .byte 0x66; movq %fs:0,%rax ... leaq x@tpoff(%rax),%rdx
2333 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -3);
2334 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 9);
2336 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
2337 view
[-3] == 0x48 && view
[-2] == 0x8d && view
[-1] == 0x3d);
2339 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(), view
[4] == 0xe8);
2341 memcpy(view
- 3, "\x66\x66\x66\x64\x48\x8b\x04\x25\0\0\0\0", 12);
2343 // The next reloc should be a PLT32 reloc against __tls_get_addr.
2345 this->skip_call_tls_get_addr_
= true;
2348 // Do a relocation in which we convert a TLS Initial-Exec to a
2352 Target_x86_64::Relocate::tls_ie_to_le(const Relocate_info
<64, false>* relinfo
,
2354 Output_segment
* tls_segment
,
2355 const elfcpp::Rela
<64, false>& rela
,
2357 elfcpp::Elf_types
<64>::Elf_Addr value
,
2358 unsigned char* view
,
2359 section_size_type view_size
)
2361 // We need to examine the opcodes to figure out which instruction we
2364 // movq foo@gottpoff(%rip),%reg ==> movq $YY,%reg
2365 // addq foo@gottpoff(%rip),%reg ==> addq $YY,%reg
2367 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -3);
2368 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 4);
2370 unsigned char op1
= view
[-3];
2371 unsigned char op2
= view
[-2];
2372 unsigned char op3
= view
[-1];
2373 unsigned char reg
= op3
>> 3;
2381 view
[-1] = 0xc0 | reg
;
2385 // Special handling for %rsp.
2389 view
[-1] = 0xc0 | reg
;
2397 view
[-1] = 0x80 | reg
| (reg
<< 3);
2400 value
-= tls_segment
->memsz();
2401 Relocate_functions
<64, false>::rela32(view
, value
, 0);
2404 // Relocate section data.
2407 Target_x86_64::relocate_section(const Relocate_info
<64, false>* relinfo
,
2408 unsigned int sh_type
,
2409 const unsigned char* prelocs
,
2411 Output_section
* output_section
,
2412 bool needs_special_offset_handling
,
2413 unsigned char* view
,
2414 elfcpp::Elf_types
<64>::Elf_Addr address
,
2415 section_size_type view_size
)
2417 gold_assert(sh_type
== elfcpp::SHT_RELA
);
2419 gold::relocate_section
<64, false, Target_x86_64
, elfcpp::SHT_RELA
,
2420 Target_x86_64::Relocate
>(
2426 needs_special_offset_handling
,
2432 // Return the size of a relocation while scanning during a relocatable
2436 Target_x86_64::Relocatable_size_for_reloc::get_size_for_reloc(
2437 unsigned int r_type
,
2442 case elfcpp::R_X86_64_NONE
:
2443 case elfcpp::R_386_GNU_VTINHERIT
:
2444 case elfcpp::R_386_GNU_VTENTRY
:
2445 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
2446 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
2447 case elfcpp::R_X86_64_TLSDESC_CALL
:
2448 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
2449 case elfcpp::R_X86_64_DTPOFF32
:
2450 case elfcpp::R_X86_64_DTPOFF64
:
2451 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
2452 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
2455 case elfcpp::R_X86_64_64
:
2456 case elfcpp::R_X86_64_PC64
:
2457 case elfcpp::R_X86_64_GOTOFF64
:
2458 case elfcpp::R_X86_64_GOTPC64
:
2459 case elfcpp::R_X86_64_PLTOFF64
:
2460 case elfcpp::R_X86_64_GOT64
:
2461 case elfcpp::R_X86_64_GOTPCREL64
:
2462 case elfcpp::R_X86_64_GOTPCREL
:
2463 case elfcpp::R_X86_64_GOTPLT64
:
2466 case elfcpp::R_X86_64_32
:
2467 case elfcpp::R_X86_64_32S
:
2468 case elfcpp::R_X86_64_PC32
:
2469 case elfcpp::R_X86_64_PLT32
:
2470 case elfcpp::R_X86_64_GOTPC32
:
2471 case elfcpp::R_X86_64_GOT32
:
2474 case elfcpp::R_X86_64_16
:
2475 case elfcpp::R_X86_64_PC16
:
2478 case elfcpp::R_X86_64_8
:
2479 case elfcpp::R_X86_64_PC8
:
2482 case elfcpp::R_X86_64_COPY
:
2483 case elfcpp::R_X86_64_GLOB_DAT
:
2484 case elfcpp::R_X86_64_JUMP_SLOT
:
2485 case elfcpp::R_X86_64_RELATIVE
:
2486 // These are outstanding tls relocs, which are unexpected when linking
2487 case elfcpp::R_X86_64_TPOFF64
:
2488 case elfcpp::R_X86_64_DTPMOD64
:
2489 case elfcpp::R_X86_64_TLSDESC
:
2490 object
->error(_("unexpected reloc %u in object file"), r_type
);
2493 case elfcpp::R_X86_64_SIZE32
:
2494 case elfcpp::R_X86_64_SIZE64
:
2496 object
->error(_("unsupported reloc %u against local symbol"), r_type
);
2501 // Scan the relocs during a relocatable link.
2504 Target_x86_64::scan_relocatable_relocs(const General_options
& options
,
2505 Symbol_table
* symtab
,
2507 Sized_relobj
<64, false>* object
,
2508 unsigned int data_shndx
,
2509 unsigned int sh_type
,
2510 const unsigned char* prelocs
,
2512 Output_section
* output_section
,
2513 bool needs_special_offset_handling
,
2514 size_t local_symbol_count
,
2515 const unsigned char* plocal_symbols
,
2516 Relocatable_relocs
* rr
)
2518 gold_assert(sh_type
== elfcpp::SHT_RELA
);
2520 typedef gold::Default_scan_relocatable_relocs
<elfcpp::SHT_RELA
,
2521 Relocatable_size_for_reloc
> Scan_relocatable_relocs
;
2523 gold::scan_relocatable_relocs
<64, false, elfcpp::SHT_RELA
,
2524 Scan_relocatable_relocs
>(
2533 needs_special_offset_handling
,
2539 // Relocate a section during a relocatable link.
2542 Target_x86_64::relocate_for_relocatable(
2543 const Relocate_info
<64, false>* relinfo
,
2544 unsigned int sh_type
,
2545 const unsigned char* prelocs
,
2547 Output_section
* output_section
,
2548 off_t offset_in_output_section
,
2549 const Relocatable_relocs
* rr
,
2550 unsigned char* view
,
2551 elfcpp::Elf_types
<64>::Elf_Addr view_address
,
2552 section_size_type view_size
,
2553 unsigned char* reloc_view
,
2554 section_size_type reloc_view_size
)
2556 gold_assert(sh_type
== elfcpp::SHT_RELA
);
2558 gold::relocate_for_relocatable
<64, false, elfcpp::SHT_RELA
>(
2563 offset_in_output_section
,
2572 // Return the value to use for a dynamic which requires special
2573 // treatment. This is how we support equality comparisons of function
2574 // pointers across shared library boundaries, as described in the
2575 // processor specific ABI supplement.
2578 Target_x86_64::do_dynsym_value(const Symbol
* gsym
) const
2580 gold_assert(gsym
->is_from_dynobj() && gsym
->has_plt_offset());
2581 return this->plt_section()->address() + gsym
->plt_offset();
2584 // Return a string used to fill a code section with nops to take up
2585 // the specified length.
2588 Target_x86_64::do_code_fill(section_size_type length
) const
2592 // Build a jmpq instruction to skip over the bytes.
2593 unsigned char jmp
[5];
2595 elfcpp::Swap_unaligned
<32, false>::writeval(jmp
+ 1, length
- 5);
2596 return (std::string(reinterpret_cast<char*>(&jmp
[0]), 5)
2597 + std::string(length
- 5, '\0'));
2600 // Nop sequences of various lengths.
2601 const char nop1
[1] = { 0x90 }; // nop
2602 const char nop2
[2] = { 0x66, 0x90 }; // xchg %ax %ax
2603 const char nop3
[3] = { 0x8d, 0x76, 0x00 }; // leal 0(%esi),%esi
2604 const char nop4
[4] = { 0x8d, 0x74, 0x26, 0x00}; // leal 0(%esi,1),%esi
2605 const char nop5
[5] = { 0x90, 0x8d, 0x74, 0x26, // nop
2606 0x00 }; // leal 0(%esi,1),%esi
2607 const char nop6
[6] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2609 const char nop7
[7] = { 0x8d, 0xb4, 0x26, 0x00, // leal 0L(%esi,1),%esi
2611 const char nop8
[8] = { 0x90, 0x8d, 0xb4, 0x26, // nop
2612 0x00, 0x00, 0x00, 0x00 }; // leal 0L(%esi,1),%esi
2613 const char nop9
[9] = { 0x89, 0xf6, 0x8d, 0xbc, // movl %esi,%esi
2614 0x27, 0x00, 0x00, 0x00, // leal 0L(%edi,1),%edi
2616 const char nop10
[10] = { 0x8d, 0x76, 0x00, 0x8d, // leal 0(%esi),%esi
2617 0xbc, 0x27, 0x00, 0x00, // leal 0L(%edi,1),%edi
2619 const char nop11
[11] = { 0x8d, 0x74, 0x26, 0x00, // leal 0(%esi,1),%esi
2620 0x8d, 0xbc, 0x27, 0x00, // leal 0L(%edi,1),%edi
2622 const char nop12
[12] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2623 0x00, 0x00, 0x8d, 0xbf, // leal 0L(%edi),%edi
2624 0x00, 0x00, 0x00, 0x00 };
2625 const char nop13
[13] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2626 0x00, 0x00, 0x8d, 0xbc, // leal 0L(%edi,1),%edi
2627 0x27, 0x00, 0x00, 0x00,
2629 const char nop14
[14] = { 0x8d, 0xb4, 0x26, 0x00, // leal 0L(%esi,1),%esi
2630 0x00, 0x00, 0x00, 0x8d, // leal 0L(%edi,1),%edi
2631 0xbc, 0x27, 0x00, 0x00,
2633 const char nop15
[15] = { 0xeb, 0x0d, 0x90, 0x90, // jmp .+15
2634 0x90, 0x90, 0x90, 0x90, // nop,nop,nop,...
2635 0x90, 0x90, 0x90, 0x90,
2638 const char* nops
[16] = {
2640 nop1
, nop2
, nop3
, nop4
, nop5
, nop6
, nop7
,
2641 nop8
, nop9
, nop10
, nop11
, nop12
, nop13
, nop14
, nop15
2644 return std::string(nops
[length
], length
);
2647 // The selector for x86_64 object files.
2649 class Target_selector_x86_64
: public Target_selector
2652 Target_selector_x86_64()
2653 : Target_selector(elfcpp::EM_X86_64
, 64, false, "elf64-x86-64")
2657 do_instantiate_target()
2658 { return new Target_x86_64(); }
2661 Target_selector_x86_64 target_selector_x86_64
;
2663 } // End anonymous namespace.