1 // x86_64.cc -- x86_64 target support for gold.
3 // Copyright (C) 2006-2022 Free Software Foundation, Inc.
4 // Written by Ian Lance Taylor <iant@google.com>.
6 // This file is part of gold.
8 // This program is free software; you can redistribute it and/or modify
9 // it under the terms of the GNU General Public License as published by
10 // the Free Software Foundation; either version 3 of the License, or
11 // (at your option) any later version.
13 // This program is distributed in the hope that it will be useful,
14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 // GNU General Public License for more details.
18 // You should have received a copy of the GNU General Public License
19 // along with this program; if not, write to the Free Software
20 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
21 // MA 02110-1301, USA.
29 #include "parameters.h"
36 #include "copy-relocs.h"
38 #include "target-reloc.h"
39 #include "target-select.h"
51 // A class to handle the .got.plt section.
53 class Output_data_got_plt_x86_64
: public Output_section_data_build
56 Output_data_got_plt_x86_64(Layout
* layout
)
57 : Output_section_data_build(8),
61 Output_data_got_plt_x86_64(Layout
* layout
, off_t data_size
)
62 : Output_section_data_build(data_size
, 8),
67 // Write out the PLT data.
69 do_write(Output_file
*);
71 // Write to a map file.
73 do_print_to_mapfile(Mapfile
* mapfile
) const
74 { mapfile
->print_output_data(this, "** GOT PLT"); }
77 // A pointer to the Layout class, so that we can find the .dynamic
78 // section when we write out the GOT PLT section.
82 // A class to handle the PLT data.
83 // This is an abstract base class that handles most of the linker details
84 // but does not know the actual contents of PLT entries. The derived
85 // classes below fill in those details.
88 class Output_data_plt_x86_64
: public Output_section_data
91 typedef Output_data_reloc
<elfcpp::SHT_RELA
, true, size
, false> Reloc_section
;
93 Output_data_plt_x86_64(Layout
* layout
, uint64_t addralign
,
94 Output_data_got
<64, false>* got
,
95 Output_data_got_plt_x86_64
* got_plt
,
96 Output_data_space
* got_irelative
)
97 : Output_section_data(addralign
), tlsdesc_rel_(NULL
),
98 irelative_rel_(NULL
), got_(got
), got_plt_(got_plt
),
99 got_irelative_(got_irelative
), count_(0), irelative_count_(0),
100 tlsdesc_got_offset_(-1U), free_list_()
101 { this->init(layout
); }
103 Output_data_plt_x86_64(Layout
* layout
, uint64_t plt_entry_size
,
104 Output_data_got
<64, false>* got
,
105 Output_data_got_plt_x86_64
* got_plt
,
106 Output_data_space
* got_irelative
,
107 unsigned int plt_count
)
108 : Output_section_data((plt_count
+ 1) * plt_entry_size
,
109 plt_entry_size
, false),
110 tlsdesc_rel_(NULL
), irelative_rel_(NULL
), got_(got
),
111 got_plt_(got_plt
), got_irelative_(got_irelative
), count_(plt_count
),
112 irelative_count_(0), tlsdesc_got_offset_(-1U), free_list_()
116 // Initialize the free list and reserve the first entry.
117 this->free_list_
.init((plt_count
+ 1) * plt_entry_size
, false);
118 this->free_list_
.remove(0, plt_entry_size
);
121 // Initialize the PLT section.
123 init(Layout
* layout
);
125 // Add an entry to the PLT.
127 add_entry(Symbol_table
*, Layout
*, Symbol
* gsym
);
129 // Add an entry to the PLT for a local STT_GNU_IFUNC symbol.
131 add_local_ifunc_entry(Symbol_table
* symtab
, Layout
*,
132 Sized_relobj_file
<size
, false>* relobj
,
133 unsigned int local_sym_index
);
135 // Add the relocation for a PLT entry.
137 add_relocation(Symbol_table
*, Layout
*, Symbol
* gsym
,
138 unsigned int got_offset
);
140 // Add the reserved TLSDESC_PLT entry to the PLT.
142 reserve_tlsdesc_entry(unsigned int got_offset
)
143 { this->tlsdesc_got_offset_
= got_offset
; }
145 // Return true if a TLSDESC_PLT entry has been reserved.
147 has_tlsdesc_entry() const
148 { return this->tlsdesc_got_offset_
!= -1U; }
150 // Return the GOT offset for the reserved TLSDESC_PLT entry.
152 get_tlsdesc_got_offset() const
153 { return this->tlsdesc_got_offset_
; }
155 // Return the offset of the reserved TLSDESC_PLT entry.
157 get_tlsdesc_plt_offset() const
159 return ((this->count_
+ this->irelative_count_
+ 1)
160 * this->get_plt_entry_size());
163 // Return the .rela.plt section data.
166 { return this->rel_
; }
168 // Return where the TLSDESC relocations should go.
170 rela_tlsdesc(Layout
*);
172 // Return where the IRELATIVE relocations should go in the PLT
175 rela_irelative(Symbol_table
*, Layout
*);
177 // Return whether we created a section for IRELATIVE relocations.
179 has_irelative_section() const
180 { return this->irelative_rel_
!= NULL
; }
182 // Get count of regular PLT entries.
184 regular_count() const
185 { return this->count_
; }
187 // Return the total number of PLT entries.
190 { return this->count_
+ this->irelative_count_
; }
192 // Return the offset of the first non-reserved PLT entry.
194 first_plt_entry_offset()
195 { return this->get_plt_entry_size(); }
197 // Return the size of a PLT entry.
199 get_plt_entry_size() const
200 { return this->do_get_plt_entry_size(); }
202 // Reserve a slot in the PLT for an existing symbol in an incremental update.
204 reserve_slot(unsigned int plt_index
)
206 this->free_list_
.remove((plt_index
+ 1) * this->get_plt_entry_size(),
207 (plt_index
+ 2) * this->get_plt_entry_size());
210 // Return the PLT address to use for a global symbol.
212 address_for_global(const Symbol
* sym
)
213 { return do_address_for_global(sym
); }
215 // Return the PLT address to use for a local symbol.
217 address_for_local(const Relobj
* obj
, unsigned int symndx
)
218 { return do_address_for_local(obj
, symndx
); }
220 // Add .eh_frame information for the PLT.
222 add_eh_frame(Layout
* layout
)
223 { this->do_add_eh_frame(layout
); }
226 Output_data_got
<64, false>*
228 { return this->got_
; }
230 Output_data_got_plt_x86_64
*
232 { return this->got_plt_
; }
235 got_irelative() const
236 { return this->got_irelative_
; }
238 // Fill in the first PLT entry.
240 fill_first_plt_entry(unsigned char* pov
,
241 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
242 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
)
243 { this->do_fill_first_plt_entry(pov
, got_address
, plt_address
); }
245 // Fill in a normal PLT entry. Returns the offset into the entry that
246 // should be the initial GOT slot value.
248 fill_plt_entry(unsigned char* pov
,
249 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
250 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
251 unsigned int got_offset
,
252 unsigned int plt_offset
,
253 unsigned int plt_index
)
255 return this->do_fill_plt_entry(pov
, got_address
, plt_address
,
256 got_offset
, plt_offset
, plt_index
);
259 // Fill in the reserved TLSDESC PLT entry.
261 fill_tlsdesc_entry(unsigned char* pov
,
262 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
263 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
264 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_base
,
265 unsigned int tlsdesc_got_offset
,
266 unsigned int plt_offset
)
268 this->do_fill_tlsdesc_entry(pov
, got_address
, plt_address
, got_base
,
269 tlsdesc_got_offset
, plt_offset
);
273 do_get_plt_entry_size() const = 0;
276 do_fill_first_plt_entry(unsigned char* pov
,
277 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_addr
,
278 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_addr
)
282 do_fill_plt_entry(unsigned char* pov
,
283 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
284 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
285 unsigned int got_offset
,
286 unsigned int plt_offset
,
287 unsigned int plt_index
) = 0;
290 do_fill_tlsdesc_entry(unsigned char* pov
,
291 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
292 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
293 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_base
,
294 unsigned int tlsdesc_got_offset
,
295 unsigned int plt_offset
) = 0;
297 // Return the PLT address to use for a global symbol.
299 do_address_for_global(const Symbol
* sym
);
301 // Return the PLT address to use for a local symbol.
303 do_address_for_local(const Relobj
* obj
, unsigned int symndx
);
306 do_add_eh_frame(Layout
* layout
) = 0;
309 do_adjust_output_section(Output_section
* os
);
311 // Write to a map file.
313 do_print_to_mapfile(Mapfile
* mapfile
) const
314 { mapfile
->print_output_data(this, _("** PLT")); }
316 // The CIE of the .eh_frame unwind information for the PLT.
317 static const int plt_eh_frame_cie_size
= 16;
318 static const unsigned char plt_eh_frame_cie
[plt_eh_frame_cie_size
];
321 // Set the final size.
323 set_final_data_size();
325 // Write out the PLT data.
327 do_write(Output_file
*);
329 // The reloc section.
331 // The TLSDESC relocs, if necessary. These must follow the regular
333 Reloc_section
* tlsdesc_rel_
;
334 // The IRELATIVE relocs, if necessary. These must follow the
335 // regular PLT relocations and the TLSDESC relocations.
336 Reloc_section
* irelative_rel_
;
338 Output_data_got
<64, false>* got_
;
339 // The .got.plt section.
340 Output_data_got_plt_x86_64
* got_plt_
;
341 // The part of the .got.plt section used for IRELATIVE relocs.
342 Output_data_space
* got_irelative_
;
343 // The number of PLT entries.
345 // Number of PLT entries with R_X86_64_IRELATIVE relocs. These
346 // follow the regular PLT entries.
347 unsigned int irelative_count_
;
348 // Offset of the reserved TLSDESC_GOT entry when needed.
349 unsigned int tlsdesc_got_offset_
;
350 // List of available regions within the section, for incremental
352 Free_list free_list_
;
356 class Output_data_plt_x86_64_standard
: public Output_data_plt_x86_64
<size
>
359 Output_data_plt_x86_64_standard(Layout
* layout
,
360 Output_data_got
<64, false>* got
,
361 Output_data_got_plt_x86_64
* got_plt
,
362 Output_data_space
* got_irelative
)
363 : Output_data_plt_x86_64
<size
>(layout
, plt_entry_size
,
364 got
, got_plt
, got_irelative
)
367 Output_data_plt_x86_64_standard(Layout
* layout
,
368 Output_data_got
<64, false>* got
,
369 Output_data_got_plt_x86_64
* got_plt
,
370 Output_data_space
* got_irelative
,
371 unsigned int plt_count
)
372 : Output_data_plt_x86_64
<size
>(layout
, plt_entry_size
,
373 got
, got_plt
, got_irelative
,
379 do_get_plt_entry_size() const
380 { return plt_entry_size
; }
383 do_add_eh_frame(Layout
* layout
)
385 layout
->add_eh_frame_for_plt(this,
386 this->plt_eh_frame_cie
,
387 this->plt_eh_frame_cie_size
,
389 plt_eh_frame_fde_size
);
393 do_fill_first_plt_entry(unsigned char* pov
,
394 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_addr
,
395 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_addr
);
398 do_fill_plt_entry(unsigned char* pov
,
399 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
400 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
401 unsigned int got_offset
,
402 unsigned int plt_offset
,
403 unsigned int plt_index
);
406 do_fill_tlsdesc_entry(unsigned char* pov
,
407 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
408 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
409 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_base
,
410 unsigned int tlsdesc_got_offset
,
411 unsigned int plt_offset
);
414 // The size of an entry in the PLT.
415 static const int plt_entry_size
= 16;
417 // The first entry in the PLT.
418 // From the AMD64 ABI: "Unlike Intel386 ABI, this ABI uses the same
419 // procedure linkage table for both programs and shared objects."
420 static const unsigned char first_plt_entry
[plt_entry_size
];
422 // Other entries in the PLT for an executable.
423 static const unsigned char plt_entry
[plt_entry_size
];
425 // The reserved TLSDESC entry in the PLT for an executable.
426 static const unsigned char tlsdesc_plt_entry
[plt_entry_size
];
428 // The .eh_frame unwind information for the PLT.
429 static const int plt_eh_frame_fde_size
= 32;
430 static const unsigned char plt_eh_frame_fde
[plt_eh_frame_fde_size
];
433 class Output_data_plt_x86_64_bnd
: public Output_data_plt_x86_64
<64>
436 Output_data_plt_x86_64_bnd(Layout
* layout
,
437 Output_data_got
<64, false>* got
,
438 Output_data_got_plt_x86_64
* got_plt
,
439 Output_data_space
* got_irelative
)
440 : Output_data_plt_x86_64
<64>(layout
, plt_entry_size
,
441 got
, got_plt
, got_irelative
),
445 Output_data_plt_x86_64_bnd(Layout
* layout
,
446 Output_data_got
<64, false>* got
,
447 Output_data_got_plt_x86_64
* got_plt
,
448 Output_data_space
* got_irelative
,
449 unsigned int plt_count
)
450 : Output_data_plt_x86_64
<64>(layout
, plt_entry_size
,
451 got
, got_plt
, got_irelative
,
458 do_get_plt_entry_size() const
459 { return plt_entry_size
; }
461 // Return the PLT address to use for a global symbol.
463 do_address_for_global(const Symbol
*);
465 // Return the PLT address to use for a local symbol.
467 do_address_for_local(const Relobj
*, unsigned int symndx
);
470 do_add_eh_frame(Layout
* layout
)
472 layout
->add_eh_frame_for_plt(this,
473 this->plt_eh_frame_cie
,
474 this->plt_eh_frame_cie_size
,
476 plt_eh_frame_fde_size
);
480 do_fill_first_plt_entry(unsigned char* pov
,
481 elfcpp::Elf_types
<64>::Elf_Addr got_addr
,
482 elfcpp::Elf_types
<64>::Elf_Addr plt_addr
);
485 do_fill_plt_entry(unsigned char* pov
,
486 elfcpp::Elf_types
<64>::Elf_Addr got_address
,
487 elfcpp::Elf_types
<64>::Elf_Addr plt_address
,
488 unsigned int got_offset
,
489 unsigned int plt_offset
,
490 unsigned int plt_index
);
493 do_fill_tlsdesc_entry(unsigned char* pov
,
494 elfcpp::Elf_types
<64>::Elf_Addr got_address
,
495 elfcpp::Elf_types
<64>::Elf_Addr plt_address
,
496 elfcpp::Elf_types
<64>::Elf_Addr got_base
,
497 unsigned int tlsdesc_got_offset
,
498 unsigned int plt_offset
);
501 fill_aplt_entry(unsigned char* pov
,
502 elfcpp::Elf_types
<64>::Elf_Addr got_address
,
503 elfcpp::Elf_types
<64>::Elf_Addr plt_address
,
504 unsigned int got_offset
,
505 unsigned int plt_offset
,
506 unsigned int plt_index
);
509 // Set the final size.
511 set_final_data_size();
513 // Write out the BND PLT data.
515 do_write(Output_file
*);
517 // Offset of the Additional PLT (if using -z bndplt).
518 unsigned int aplt_offset_
;
520 // The size of an entry in the PLT.
521 static const int plt_entry_size
= 16;
523 // The size of an entry in the additional PLT.
524 static const int aplt_entry_size
= 8;
526 // The first entry in the PLT.
527 // From the AMD64 ABI: "Unlike Intel386 ABI, this ABI uses the same
528 // procedure linkage table for both programs and shared objects."
529 static const unsigned char first_plt_entry
[plt_entry_size
];
531 // Other entries in the PLT for an executable.
532 static const unsigned char plt_entry
[plt_entry_size
];
534 // Entries in the additional PLT.
535 static const unsigned char aplt_entry
[aplt_entry_size
];
537 // The reserved TLSDESC entry in the PLT for an executable.
538 static const unsigned char tlsdesc_plt_entry
[plt_entry_size
];
540 // The .eh_frame unwind information for the PLT.
541 static const int plt_eh_frame_fde_size
= 32;
542 static const unsigned char plt_eh_frame_fde
[plt_eh_frame_fde_size
];
545 // We use this PLT when Indirect Branch Tracking (IBT) is enabled.
548 class Output_data_plt_x86_64_ibt
: public Output_data_plt_x86_64
<size
>
551 Output_data_plt_x86_64_ibt(Layout
* layout
,
552 Output_data_got
<64, false>* got
,
553 Output_data_got_plt_x86_64
* got_plt
,
554 Output_data_space
* got_irelative
)
555 : Output_data_plt_x86_64
<size
>(layout
, plt_entry_size
,
556 got
, got_plt
, got_irelative
),
560 Output_data_plt_x86_64_ibt(Layout
* layout
,
561 Output_data_got
<64, false>* got
,
562 Output_data_got_plt_x86_64
* got_plt
,
563 Output_data_space
* got_irelative
,
564 unsigned int plt_count
)
565 : Output_data_plt_x86_64
<size
>(layout
, plt_entry_size
,
566 got
, got_plt
, got_irelative
,
573 do_get_plt_entry_size() const
574 { return plt_entry_size
; }
576 // Return the PLT address to use for a global symbol.
578 do_address_for_global(const Symbol
*);
580 // Return the PLT address to use for a local symbol.
582 do_address_for_local(const Relobj
*, unsigned int symndx
);
585 do_add_eh_frame(Layout
* layout
)
587 layout
->add_eh_frame_for_plt(this,
588 this->plt_eh_frame_cie
,
589 this->plt_eh_frame_cie_size
,
591 plt_eh_frame_fde_size
);
595 do_fill_first_plt_entry(unsigned char* pov
,
596 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_addr
,
597 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_addr
);
600 do_fill_plt_entry(unsigned char* pov
,
601 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
602 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
603 unsigned int got_offset
,
604 unsigned int plt_offset
,
605 unsigned int plt_index
);
608 do_fill_tlsdesc_entry(unsigned char* pov
,
609 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
610 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
611 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_base
,
612 unsigned int tlsdesc_got_offset
,
613 unsigned int plt_offset
);
616 fill_aplt_entry(unsigned char* pov
,
617 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
618 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
619 unsigned int got_offset
,
620 unsigned int plt_offset
,
621 unsigned int plt_index
);
624 // Set the final size.
626 set_final_data_size();
628 // Write out the BND PLT data.
630 do_write(Output_file
*);
632 // Offset of the Additional PLT (if using -z bndplt).
633 unsigned int aplt_offset_
;
635 // The size of an entry in the PLT.
636 static const int plt_entry_size
= 16;
638 // The size of an entry in the additional PLT.
639 static const int aplt_entry_size
= 16;
641 // The first entry in the PLT.
642 // From the AMD64 ABI: "Unlike Intel386 ABI, this ABI uses the same
643 // procedure linkage table for both programs and shared objects."
644 static const unsigned char first_plt_entry
[plt_entry_size
];
646 // Other entries in the PLT for an executable.
647 static const unsigned char plt_entry
[plt_entry_size
];
649 // Entries in the additional PLT.
650 static const unsigned char aplt_entry
[aplt_entry_size
];
652 // The reserved TLSDESC entry in the PLT for an executable.
653 static const unsigned char tlsdesc_plt_entry
[plt_entry_size
];
655 // The .eh_frame unwind information for the PLT.
656 static const int plt_eh_frame_fde_size
= 32;
657 static const unsigned char plt_eh_frame_fde
[plt_eh_frame_fde_size
];
664 Lazy_view(Sized_relobj_file
<size
, false>* object
, unsigned int data_shndx
)
665 : object_(object
), data_shndx_(data_shndx
), view_(NULL
), view_size_(0)
669 operator[](size_t offset
)
671 if (this->view_
== NULL
)
672 this->view_
= this->object_
->section_contents(this->data_shndx_
,
675 if (offset
>= this->view_size_
)
677 return this->view_
[offset
];
681 Sized_relobj_file
<size
, false>* object_
;
682 unsigned int data_shndx_
;
683 const unsigned char* view_
;
684 section_size_type view_size_
;
687 // The x86_64 target class.
689 // http://www.x86-64.org/documentation/abi.pdf
690 // TLS info comes from
691 // http://people.redhat.com/drepper/tls.pdf
692 // http://www.lsd.ic.unicamp.br/~oliva/writeups/TLS/RFC-TLSDESC-x86.txt
695 class Target_x86_64
: public Sized_target
<size
, false>
698 // In the x86_64 ABI (p 68), it says "The AMD64 ABI architectures
699 // uses only Elf64_Rela relocation entries with explicit addends."
700 typedef Output_data_reloc
<elfcpp::SHT_RELA
, true, size
, false> Reloc_section
;
702 Target_x86_64(const Target::Target_info
* info
= &x86_64_info
)
703 : Sized_target
<size
, false>(info
),
704 got_(NULL
), plt_(NULL
), got_plt_(NULL
), got_irelative_(NULL
),
705 got_tlsdesc_(NULL
), global_offset_table_(NULL
), rela_dyn_(NULL
),
706 rela_irelative_(NULL
), copy_relocs_(elfcpp::R_X86_64_COPY
),
707 got_mod_index_offset_(-1U), tlsdesc_reloc_info_(),
708 tls_base_symbol_defined_(false), isa_1_used_(0), isa_1_needed_(0),
709 feature_1_(0), feature_2_used_(0), feature_2_needed_(0),
710 object_isa_1_used_(0), object_feature_1_(0),
711 object_feature_2_used_(0), seen_first_object_(false)
714 // Hook for a new output section.
716 do_new_output_section(Output_section
*) const;
718 // Scan the relocations to look for symbol adjustments.
720 gc_process_relocs(Symbol_table
* symtab
,
722 Sized_relobj_file
<size
, false>* object
,
723 unsigned int data_shndx
,
724 unsigned int sh_type
,
725 const unsigned char* prelocs
,
727 Output_section
* output_section
,
728 bool needs_special_offset_handling
,
729 size_t local_symbol_count
,
730 const unsigned char* plocal_symbols
);
732 // Scan the relocations to look for symbol adjustments.
734 scan_relocs(Symbol_table
* symtab
,
736 Sized_relobj_file
<size
, false>* object
,
737 unsigned int data_shndx
,
738 unsigned int sh_type
,
739 const unsigned char* prelocs
,
741 Output_section
* output_section
,
742 bool needs_special_offset_handling
,
743 size_t local_symbol_count
,
744 const unsigned char* plocal_symbols
);
746 // Finalize the sections.
748 do_finalize_sections(Layout
*, const Input_objects
*, Symbol_table
*);
750 // Return the value to use for a dynamic which requires special
753 do_dynsym_value(const Symbol
*) const;
755 // Relocate a section.
757 relocate_section(const Relocate_info
<size
, false>*,
758 unsigned int sh_type
,
759 const unsigned char* prelocs
,
761 Output_section
* output_section
,
762 bool needs_special_offset_handling
,
764 typename
elfcpp::Elf_types
<size
>::Elf_Addr view_address
,
765 section_size_type view_size
,
766 const Reloc_symbol_changes
*);
768 // Scan the relocs during a relocatable link.
770 scan_relocatable_relocs(Symbol_table
* symtab
,
772 Sized_relobj_file
<size
, false>* object
,
773 unsigned int data_shndx
,
774 unsigned int sh_type
,
775 const unsigned char* prelocs
,
777 Output_section
* output_section
,
778 bool needs_special_offset_handling
,
779 size_t local_symbol_count
,
780 const unsigned char* plocal_symbols
,
781 Relocatable_relocs
*);
783 // Scan the relocs for --emit-relocs.
785 emit_relocs_scan(Symbol_table
* symtab
,
787 Sized_relobj_file
<size
, false>* object
,
788 unsigned int data_shndx
,
789 unsigned int sh_type
,
790 const unsigned char* prelocs
,
792 Output_section
* output_section
,
793 bool needs_special_offset_handling
,
794 size_t local_symbol_count
,
795 const unsigned char* plocal_syms
,
796 Relocatable_relocs
* rr
);
798 // Emit relocations for a section.
801 const Relocate_info
<size
, false>*,
802 unsigned int sh_type
,
803 const unsigned char* prelocs
,
805 Output_section
* output_section
,
806 typename
elfcpp::Elf_types
<size
>::Elf_Off offset_in_output_section
,
808 typename
elfcpp::Elf_types
<size
>::Elf_Addr view_address
,
809 section_size_type view_size
,
810 unsigned char* reloc_view
,
811 section_size_type reloc_view_size
);
813 // Return a string used to fill a code section with nops.
815 do_code_fill(section_size_type length
) const;
817 // Return whether SYM is defined by the ABI.
819 do_is_defined_by_abi(const Symbol
* sym
) const
820 { return strcmp(sym
->name(), "__tls_get_addr") == 0; }
822 // Return the symbol index to use for a target specific relocation.
823 // The only target specific relocation is R_X86_64_TLSDESC for a
824 // local symbol, which is an absolute reloc.
826 do_reloc_symbol_index(void*, unsigned int r_type
) const
828 gold_assert(r_type
== elfcpp::R_X86_64_TLSDESC
);
832 // Return the addend to use for a target specific relocation.
834 do_reloc_addend(void* arg
, unsigned int r_type
, uint64_t addend
) const;
836 // Return the PLT section.
838 do_plt_address_for_global(const Symbol
* gsym
) const
839 { return this->plt_section()->address_for_global(gsym
); }
842 do_plt_address_for_local(const Relobj
* relobj
, unsigned int symndx
) const
843 { return this->plt_section()->address_for_local(relobj
, symndx
); }
845 // This function should be defined in targets that can use relocation
846 // types to determine (implemented in local_reloc_may_be_function_pointer
847 // and global_reloc_may_be_function_pointer)
848 // if a function's pointer is taken. ICF uses this in safe mode to only
849 // fold those functions whose pointer is defintely not taken. For x86_64
850 // pie binaries, safe ICF cannot be done by looking at only relocation
851 // types, and for certain cases (e.g. R_X86_64_PC32), the instruction
852 // opcode is checked as well to distinguish a function call from taking
853 // a function's pointer.
855 do_can_check_for_function_pointers() const
858 // Return the base for a DW_EH_PE_datarel encoding.
860 do_ehframe_datarel_base() const;
862 // Adjust -fsplit-stack code which calls non-split-stack code.
864 do_calls_non_split(Relobj
* object
, unsigned int shndx
,
865 section_offset_type fnoffset
, section_size_type fnsize
,
866 const unsigned char* prelocs
, size_t reloc_count
,
867 unsigned char* view
, section_size_type view_size
,
868 std::string
* from
, std::string
* to
) const;
870 // Return the size of the GOT section.
874 gold_assert(this->got_
!= NULL
);
875 return this->got_
->data_size();
878 // Return the number of entries in the GOT.
880 got_entry_count() const
882 if (this->got_
== NULL
)
884 return this->got_size() / 8;
887 // Return the number of entries in the PLT.
889 plt_entry_count() const;
891 // Return the offset of the first non-reserved PLT entry.
893 first_plt_entry_offset() const;
895 // Return the size of each PLT entry.
897 plt_entry_size() const;
899 // Return the size of each GOT entry.
901 got_entry_size() const
904 // Create the GOT section for an incremental update.
905 Output_data_got_base
*
906 init_got_plt_for_update(Symbol_table
* symtab
,
908 unsigned int got_count
,
909 unsigned int plt_count
);
911 // Reserve a GOT entry for a local symbol, and regenerate any
912 // necessary dynamic relocations.
914 reserve_local_got_entry(unsigned int got_index
,
915 Sized_relobj
<size
, false>* obj
,
917 unsigned int got_type
);
919 // Reserve a GOT entry for a global symbol, and regenerate any
920 // necessary dynamic relocations.
922 reserve_global_got_entry(unsigned int got_index
, Symbol
* gsym
,
923 unsigned int got_type
);
925 // Register an existing PLT entry for a global symbol.
927 register_global_plt_entry(Symbol_table
*, Layout
*, unsigned int plt_index
,
930 // Force a COPY relocation for a given symbol.
932 emit_copy_reloc(Symbol_table
*, Symbol
*, Output_section
*, off_t
);
934 // Apply an incremental relocation.
936 apply_relocation(const Relocate_info
<size
, false>* relinfo
,
937 typename
elfcpp::Elf_types
<size
>::Elf_Addr r_offset
,
939 typename
elfcpp::Elf_types
<size
>::Elf_Swxword r_addend
,
942 typename
elfcpp::Elf_types
<size
>::Elf_Addr address
,
943 section_size_type view_size
);
945 // Add a new reloc argument, returning the index in the vector.
947 add_tlsdesc_info(Sized_relobj_file
<size
, false>* object
, unsigned int r_sym
)
949 this->tlsdesc_reloc_info_
.push_back(Tlsdesc_info(object
, r_sym
));
950 return this->tlsdesc_reloc_info_
.size() - 1;
953 Output_data_plt_x86_64
<size
>*
954 make_data_plt(Layout
* layout
,
955 Output_data_got
<64, false>* got
,
956 Output_data_got_plt_x86_64
* got_plt
,
957 Output_data_space
* got_irelative
)
959 return this->do_make_data_plt(layout
, got
, got_plt
, got_irelative
);
962 Output_data_plt_x86_64
<size
>*
963 make_data_plt(Layout
* layout
,
964 Output_data_got
<64, false>* got
,
965 Output_data_got_plt_x86_64
* got_plt
,
966 Output_data_space
* got_irelative
,
967 unsigned int plt_count
)
969 return this->do_make_data_plt(layout
, got
, got_plt
, got_irelative
,
973 virtual Output_data_plt_x86_64
<size
>*
974 do_make_data_plt(Layout
* layout
,
975 Output_data_got
<64, false>* got
,
976 Output_data_got_plt_x86_64
* got_plt
,
977 Output_data_space
* got_irelative
);
979 virtual Output_data_plt_x86_64
<size
>*
980 do_make_data_plt(Layout
* layout
,
981 Output_data_got
<64, false>* got
,
982 Output_data_got_plt_x86_64
* got_plt
,
983 Output_data_space
* got_irelative
,
984 unsigned int plt_count
);
987 // The class which scans relocations.
992 : issued_non_pic_error_(false)
996 get_reference_flags(unsigned int r_type
);
999 local(Symbol_table
* symtab
, Layout
* layout
, Target_x86_64
* target
,
1000 Sized_relobj_file
<size
, false>* object
,
1001 unsigned int data_shndx
,
1002 Output_section
* output_section
,
1003 const elfcpp::Rela
<size
, false>& reloc
, unsigned int r_type
,
1004 const elfcpp::Sym
<size
, false>& lsym
,
1008 global(Symbol_table
* symtab
, Layout
* layout
, Target_x86_64
* target
,
1009 Sized_relobj_file
<size
, false>* object
,
1010 unsigned int data_shndx
,
1011 Output_section
* output_section
,
1012 const elfcpp::Rela
<size
, false>& reloc
, unsigned int r_type
,
1016 local_reloc_may_be_function_pointer(Symbol_table
* symtab
, Layout
* layout
,
1017 Target_x86_64
* target
,
1018 Sized_relobj_file
<size
, false>* object
,
1019 unsigned int data_shndx
,
1020 Output_section
* output_section
,
1021 const elfcpp::Rela
<size
, false>& reloc
,
1022 unsigned int r_type
,
1023 const elfcpp::Sym
<size
, false>& lsym
);
1026 global_reloc_may_be_function_pointer(Symbol_table
* symtab
, Layout
* layout
,
1027 Target_x86_64
* target
,
1028 Sized_relobj_file
<size
, false>* object
,
1029 unsigned int data_shndx
,
1030 Output_section
* output_section
,
1031 const elfcpp::Rela
<size
, false>& reloc
,
1032 unsigned int r_type
,
1037 unsupported_reloc_local(Sized_relobj_file
<size
, false>*,
1038 unsigned int r_type
);
1041 unsupported_reloc_global(Sized_relobj_file
<size
, false>*,
1042 unsigned int r_type
, Symbol
*);
1045 check_non_pic(Relobj
*, unsigned int r_type
, Symbol
*);
1048 possible_function_pointer_reloc(Sized_relobj_file
<size
, false>* src_obj
,
1049 unsigned int src_indx
,
1050 unsigned int r_offset
,
1051 unsigned int r_type
);
1054 reloc_needs_plt_for_ifunc(Sized_relobj_file
<size
, false>*,
1055 unsigned int r_type
);
1057 // Whether we have issued an error about a non-PIC compilation.
1058 bool issued_non_pic_error_
;
1061 // The class which implements relocation.
1066 : skip_call_tls_get_addr_(false)
1071 if (this->skip_call_tls_get_addr_
)
1073 // FIXME: This needs to specify the location somehow.
1074 gold_error(_("missing expected TLS relocation"));
1078 // Do a relocation. Return false if the caller should not issue
1079 // any warnings about this relocation.
1081 relocate(const Relocate_info
<size
, false>*, unsigned int,
1082 Target_x86_64
*, Output_section
*, size_t, const unsigned char*,
1083 const Sized_symbol
<size
>*, const Symbol_value
<size
>*,
1084 unsigned char*, typename
elfcpp::Elf_types
<size
>::Elf_Addr
,
1088 // Do a TLS relocation.
1090 relocate_tls(const Relocate_info
<size
, false>*, Target_x86_64
*,
1091 size_t relnum
, const elfcpp::Rela
<size
, false>&,
1092 unsigned int r_type
, const Sized_symbol
<size
>*,
1093 const Symbol_value
<size
>*,
1094 unsigned char*, typename
elfcpp::Elf_types
<size
>::Elf_Addr
,
1097 // Do a TLS General-Dynamic to Initial-Exec transition.
1099 tls_gd_to_ie(const Relocate_info
<size
, false>*, size_t relnum
,
1100 const elfcpp::Rela
<size
, false>&, unsigned int r_type
,
1101 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
1102 unsigned char* view
,
1103 typename
elfcpp::Elf_types
<size
>::Elf_Addr
,
1104 section_size_type view_size
);
1106 // Do a TLS General-Dynamic to Local-Exec transition.
1108 tls_gd_to_le(const Relocate_info
<size
, false>*, size_t relnum
,
1109 Output_segment
* tls_segment
,
1110 const elfcpp::Rela
<size
, false>&, unsigned int r_type
,
1111 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
1112 unsigned char* view
,
1113 section_size_type view_size
);
1115 // Do a TLSDESC-style General-Dynamic to Initial-Exec transition.
1117 tls_desc_gd_to_ie(const Relocate_info
<size
, false>*, size_t relnum
,
1118 const elfcpp::Rela
<size
, false>&, unsigned int r_type
,
1119 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
1120 unsigned char* view
,
1121 typename
elfcpp::Elf_types
<size
>::Elf_Addr
,
1122 section_size_type view_size
);
1124 // Do a TLSDESC-style General-Dynamic to Local-Exec transition.
1126 tls_desc_gd_to_le(const Relocate_info
<size
, false>*, size_t relnum
,
1127 Output_segment
* tls_segment
,
1128 const elfcpp::Rela
<size
, false>&, unsigned int r_type
,
1129 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
1130 unsigned char* view
,
1131 section_size_type view_size
);
1133 // Do a TLS Local-Dynamic to Local-Exec transition.
1135 tls_ld_to_le(const Relocate_info
<size
, false>*, size_t relnum
,
1136 Output_segment
* tls_segment
,
1137 const elfcpp::Rela
<size
, false>&, unsigned int r_type
,
1138 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
1139 unsigned char* view
,
1140 section_size_type view_size
);
1142 // Do a TLS Initial-Exec to Local-Exec transition.
1144 tls_ie_to_le(const Relocate_info
<size
, false>*, size_t relnum
,
1145 Output_segment
* tls_segment
,
1146 const elfcpp::Rela
<size
, false>&, unsigned int r_type
,
1147 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
1148 unsigned char* view
,
1149 section_size_type view_size
);
1151 // This is set if we should skip the next reloc, which should be a
1152 // PLT32 reloc against ___tls_get_addr.
1153 bool skip_call_tls_get_addr_
;
1156 // Check if relocation against this symbol is a candidate for
1158 // mov foo@GOTPCREL(%rip), %reg
1159 // to lea foo(%rip), %reg.
1160 template<class View_type
>
1162 can_convert_mov_to_lea(const Symbol
* gsym
, unsigned int r_type
,
1163 size_t r_offset
, View_type
* view
)
1165 gold_assert(gsym
!= NULL
);
1166 // We cannot do the conversion unless it's one of these relocations.
1167 if (r_type
!= elfcpp::R_X86_64_GOTPCREL
1168 && r_type
!= elfcpp::R_X86_64_GOTPCRELX
1169 && r_type
!= elfcpp::R_X86_64_REX_GOTPCRELX
)
1171 // We cannot convert references to IFUNC symbols, or to symbols that
1172 // are not local to the current module.
1173 // We can't do predefined symbols because they may become undefined
1174 // (e.g., __ehdr_start when the headers aren't mapped to a segment).
1175 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
1176 || gsym
->is_undefined()
1177 || gsym
->is_predefined()
1178 || gsym
->is_from_dynobj()
1179 || gsym
->is_preemptible())
1181 // If we are building a shared object and the symbol is protected, we may
1182 // need to go through the GOT.
1183 if (parameters
->options().shared()
1184 && gsym
->visibility() == elfcpp::STV_PROTECTED
)
1186 // We cannot convert references to the _DYNAMIC symbol.
1187 if (strcmp(gsym
->name(), "_DYNAMIC") == 0)
1189 // Check for a MOV opcode.
1190 return (*view
)[r_offset
- 2] == 0x8b;
1194 // callq *foo@GOTPCRELX(%rip) to
1196 // and jmpq *foo@GOTPCRELX(%rip) to
1199 template<class View_type
>
1201 can_convert_callq_to_direct(const Symbol
* gsym
, unsigned int r_type
,
1202 size_t r_offset
, View_type
* view
)
1204 gold_assert(gsym
!= NULL
);
1205 // We cannot do the conversion unless it's a GOTPCRELX relocation.
1206 if (r_type
!= elfcpp::R_X86_64_GOTPCRELX
)
1208 // We cannot convert references to IFUNC symbols, or to symbols that
1209 // are not local to the current module.
1210 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
1211 || gsym
->is_undefined ()
1212 || gsym
->is_from_dynobj()
1213 || gsym
->is_preemptible())
1215 // Check for a CALLQ or JMPQ opcode.
1216 return ((*view
)[r_offset
- 2] == 0xff
1217 && ((*view
)[r_offset
- 1] == 0x15
1218 || (*view
)[r_offset
- 1] == 0x25));
1221 // Adjust TLS relocation type based on the options and whether this
1222 // is a local symbol.
1223 static tls::Tls_optimization
1224 optimize_tls_reloc(bool is_final
, int r_type
);
1226 // Get the GOT section, creating it if necessary.
1227 Output_data_got
<64, false>*
1228 got_section(Symbol_table
*, Layout
*);
1230 // Get the GOT PLT section.
1231 Output_data_got_plt_x86_64
*
1232 got_plt_section() const
1234 gold_assert(this->got_plt_
!= NULL
);
1235 return this->got_plt_
;
1238 // Get the GOT section for TLSDESC entries.
1239 Output_data_got
<64, false>*
1240 got_tlsdesc_section() const
1242 gold_assert(this->got_tlsdesc_
!= NULL
);
1243 return this->got_tlsdesc_
;
1246 // Create the PLT section.
1248 make_plt_section(Symbol_table
* symtab
, Layout
* layout
);
1250 // Create a PLT entry for a global symbol.
1252 make_plt_entry(Symbol_table
*, Layout
*, Symbol
*);
1254 // Create a PLT entry for a local STT_GNU_IFUNC symbol.
1256 make_local_ifunc_plt_entry(Symbol_table
*, Layout
*,
1257 Sized_relobj_file
<size
, false>* relobj
,
1258 unsigned int local_sym_index
);
1260 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
1262 define_tls_base_symbol(Symbol_table
*, Layout
*);
1264 // Create the reserved PLT and GOT entries for the TLS descriptor resolver.
1266 reserve_tlsdesc_entries(Symbol_table
* symtab
, Layout
* layout
);
1268 // Create a GOT entry for the TLS module index.
1270 got_mod_index_entry(Symbol_table
* symtab
, Layout
* layout
,
1271 Sized_relobj_file
<size
, false>* object
);
1273 // Get the PLT section.
1274 Output_data_plt_x86_64
<size
>*
1277 gold_assert(this->plt_
!= NULL
);
1281 // Get the dynamic reloc section, creating it if necessary.
1283 rela_dyn_section(Layout
*);
1285 // Get the section to use for TLSDESC relocations.
1287 rela_tlsdesc_section(Layout
*) const;
1289 // Get the section to use for IRELATIVE relocations.
1291 rela_irelative_section(Layout
*);
1293 // Add a potential copy relocation.
1295 copy_reloc(Symbol_table
* symtab
, Layout
* layout
,
1296 Sized_relobj_file
<size
, false>* object
,
1297 unsigned int shndx
, Output_section
* output_section
,
1298 Symbol
* sym
, const elfcpp::Rela
<size
, false>& reloc
)
1300 unsigned int r_type
= elfcpp::elf_r_type
<size
>(reloc
.get_r_info());
1301 this->copy_relocs_
.copy_reloc(symtab
, layout
,
1302 symtab
->get_sized_symbol
<size
>(sym
),
1303 object
, shndx
, output_section
,
1304 r_type
, reloc
.get_r_offset(),
1305 reloc
.get_r_addend(),
1306 this->rela_dyn_section(layout
));
1309 // Record a target-specific program property in the .note.gnu.property
1312 record_gnu_property(unsigned int, unsigned int, size_t,
1313 const unsigned char*, const Object
*);
1315 // Merge the target-specific program properties from the current object.
1317 merge_gnu_properties(const Object
*);
1319 // Finalize the target-specific program properties and add them back to
1322 do_finalize_gnu_properties(Layout
*) const;
1324 // Information about this specific target which we pass to the
1325 // general Target structure.
1326 static const Target::Target_info x86_64_info
;
1328 // The types of GOT entries needed for this platform.
1329 // These values are exposed to the ABI in an incremental link.
1330 // Do not renumber existing values without changing the version
1331 // number of the .gnu_incremental_inputs section.
1334 GOT_TYPE_STANDARD
= 0, // GOT entry for a regular symbol
1335 GOT_TYPE_TLS_OFFSET
= 1, // GOT entry for TLS offset
1336 GOT_TYPE_TLS_PAIR
= 2, // GOT entry for TLS module/offset pair
1337 GOT_TYPE_TLS_DESC
= 3 // GOT entry for TLS_DESC pair
1340 // This type is used as the argument to the target specific
1341 // relocation routines. The only target specific reloc is
1342 // R_X86_64_TLSDESC against a local symbol.
1345 Tlsdesc_info(Sized_relobj_file
<size
, false>* a_object
, unsigned int a_r_sym
)
1346 : object(a_object
), r_sym(a_r_sym
)
1349 // The object in which the local symbol is defined.
1350 Sized_relobj_file
<size
, false>* object
;
1351 // The local symbol index in the object.
1356 Output_data_got
<64, false>* got_
;
1358 Output_data_plt_x86_64
<size
>* plt_
;
1359 // The GOT PLT section.
1360 Output_data_got_plt_x86_64
* got_plt_
;
1361 // The GOT section for IRELATIVE relocations.
1362 Output_data_space
* got_irelative_
;
1363 // The GOT section for TLSDESC relocations.
1364 Output_data_got
<64, false>* got_tlsdesc_
;
1365 // The _GLOBAL_OFFSET_TABLE_ symbol.
1366 Symbol
* global_offset_table_
;
1367 // The dynamic reloc section.
1368 Reloc_section
* rela_dyn_
;
1369 // The section to use for IRELATIVE relocs.
1370 Reloc_section
* rela_irelative_
;
1371 // Relocs saved to avoid a COPY reloc.
1372 Copy_relocs
<elfcpp::SHT_RELA
, size
, false> copy_relocs_
;
1373 // Offset of the GOT entry for the TLS module index.
1374 unsigned int got_mod_index_offset_
;
1375 // We handle R_X86_64_TLSDESC against a local symbol as a target
1376 // specific relocation. Here we store the object and local symbol
1377 // index for the relocation.
1378 std::vector
<Tlsdesc_info
> tlsdesc_reloc_info_
;
1379 // True if the _TLS_MODULE_BASE_ symbol has been defined.
1380 bool tls_base_symbol_defined_
;
1381 // Target-specific program properties, from .note.gnu.property section.
1382 // Each bit represents a specific feature.
1383 uint32_t isa_1_used_
;
1384 uint32_t isa_1_needed_
;
1385 uint32_t feature_1_
;
1386 uint32_t feature_2_used_
;
1387 uint32_t feature_2_needed_
;
1388 // Target-specific properties from the current object.
1389 // These bits get ORed into ISA_1_USED_ after all properties for the object
1390 // have been processed. But if either is all zeroes (as when the property
1391 // is absent from an object), the result should be all zeroes.
1392 // (See PR ld/23486.)
1393 uint32_t object_isa_1_used_
;
1394 // These bits get ANDed into FEATURE_1_ after all properties for the object
1395 // have been processed.
1396 uint32_t object_feature_1_
;
1397 uint32_t object_feature_2_used_
;
1398 // Whether we have seen our first object, for use in initializing FEATURE_1_.
1399 bool seen_first_object_
;
1403 const Target::Target_info Target_x86_64
<64>::x86_64_info
=
1406 false, // is_big_endian
1407 elfcpp::EM_X86_64
, // machine_code
1408 false, // has_make_symbol
1409 false, // has_resolve
1410 true, // has_code_fill
1411 true, // is_default_stack_executable
1412 true, // can_icf_inline_merge_sections
1414 "/lib/ld64.so.1", // program interpreter
1415 0x400000, // default_text_segment_address
1416 0x1000, // abi_pagesize (overridable by -z max-page-size)
1417 0x1000, // common_pagesize (overridable by -z common-page-size)
1418 false, // isolate_execinstr
1420 elfcpp::SHN_UNDEF
, // small_common_shndx
1421 elfcpp::SHN_X86_64_LCOMMON
, // large_common_shndx
1422 0, // small_common_section_flags
1423 elfcpp::SHF_X86_64_LARGE
, // large_common_section_flags
1424 NULL
, // attributes_section
1425 NULL
, // attributes_vendor
1426 "_start", // entry_symbol_name
1427 32, // hash_entry_size
1428 elfcpp::SHT_X86_64_UNWIND
, // unwind_section_type
1432 const Target::Target_info Target_x86_64
<32>::x86_64_info
=
1435 false, // is_big_endian
1436 elfcpp::EM_X86_64
, // machine_code
1437 false, // has_make_symbol
1438 false, // has_resolve
1439 true, // has_code_fill
1440 true, // is_default_stack_executable
1441 true, // can_icf_inline_merge_sections
1443 "/libx32/ldx32.so.1", // program interpreter
1444 0x400000, // default_text_segment_address
1445 0x1000, // abi_pagesize (overridable by -z max-page-size)
1446 0x1000, // common_pagesize (overridable by -z common-page-size)
1447 false, // isolate_execinstr
1449 elfcpp::SHN_UNDEF
, // small_common_shndx
1450 elfcpp::SHN_X86_64_LCOMMON
, // large_common_shndx
1451 0, // small_common_section_flags
1452 elfcpp::SHF_X86_64_LARGE
, // large_common_section_flags
1453 NULL
, // attributes_section
1454 NULL
, // attributes_vendor
1455 "_start", // entry_symbol_name
1456 32, // hash_entry_size
1457 elfcpp::SHT_X86_64_UNWIND
, // unwind_section_type
1460 // This is called when a new output section is created. This is where
1461 // we handle the SHF_X86_64_LARGE.
1465 Target_x86_64
<size
>::do_new_output_section(Output_section
* os
) const
1467 if ((os
->flags() & elfcpp::SHF_X86_64_LARGE
) != 0)
1468 os
->set_is_large_section();
1471 // Get the GOT section, creating it if necessary.
1474 Output_data_got
<64, false>*
1475 Target_x86_64
<size
>::got_section(Symbol_table
* symtab
, Layout
* layout
)
1477 if (this->got_
== NULL
)
1479 gold_assert(symtab
!= NULL
&& layout
!= NULL
);
1481 // When using -z now, we can treat .got.plt as a relro section.
1482 // Without -z now, it is modified after program startup by lazy
1484 bool is_got_plt_relro
= parameters
->options().now();
1485 Output_section_order got_order
= (is_got_plt_relro
1487 : ORDER_RELRO_LAST
);
1488 Output_section_order got_plt_order
= (is_got_plt_relro
1490 : ORDER_NON_RELRO_FIRST
);
1492 this->got_
= new Output_data_got
<64, false>();
1494 layout
->add_output_section_data(".got", elfcpp::SHT_PROGBITS
,
1496 | elfcpp::SHF_WRITE
),
1497 this->got_
, got_order
, true);
1499 this->got_plt_
= new Output_data_got_plt_x86_64(layout
);
1500 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
1502 | elfcpp::SHF_WRITE
),
1503 this->got_plt_
, got_plt_order
,
1506 // The first three entries are reserved.
1507 this->got_plt_
->set_current_data_size(3 * 8);
1509 if (!is_got_plt_relro
)
1511 // Those bytes can go into the relro segment.
1512 layout
->increase_relro(3 * 8);
1515 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
1516 this->global_offset_table_
=
1517 symtab
->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL
,
1518 Symbol_table::PREDEFINED
,
1520 0, 0, elfcpp::STT_OBJECT
,
1522 elfcpp::STV_HIDDEN
, 0,
1525 // If there are any IRELATIVE relocations, they get GOT entries
1526 // in .got.plt after the jump slot entries.
1527 this->got_irelative_
= new Output_data_space(8, "** GOT IRELATIVE PLT");
1528 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
1530 | elfcpp::SHF_WRITE
),
1531 this->got_irelative_
,
1532 got_plt_order
, is_got_plt_relro
);
1534 // If there are any TLSDESC relocations, they get GOT entries in
1535 // .got.plt after the jump slot and IRELATIVE entries.
1536 this->got_tlsdesc_
= new Output_data_got
<64, false>();
1537 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
1539 | elfcpp::SHF_WRITE
),
1541 got_plt_order
, is_got_plt_relro
);
1547 // Get the dynamic reloc section, creating it if necessary.
1550 typename Target_x86_64
<size
>::Reloc_section
*
1551 Target_x86_64
<size
>::rela_dyn_section(Layout
* layout
)
1553 if (this->rela_dyn_
== NULL
)
1555 gold_assert(layout
!= NULL
);
1556 this->rela_dyn_
= new Reloc_section(parameters
->options().combreloc());
1557 layout
->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA
,
1558 elfcpp::SHF_ALLOC
, this->rela_dyn_
,
1559 ORDER_DYNAMIC_RELOCS
, false);
1561 return this->rela_dyn_
;
1564 // Get the section to use for IRELATIVE relocs, creating it if
1565 // necessary. These go in .rela.dyn, but only after all other dynamic
1566 // relocations. They need to follow the other dynamic relocations so
1567 // that they can refer to global variables initialized by those
1571 typename Target_x86_64
<size
>::Reloc_section
*
1572 Target_x86_64
<size
>::rela_irelative_section(Layout
* layout
)
1574 if (this->rela_irelative_
== NULL
)
1576 // Make sure we have already created the dynamic reloc section.
1577 this->rela_dyn_section(layout
);
1578 this->rela_irelative_
= new Reloc_section(false);
1579 layout
->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA
,
1580 elfcpp::SHF_ALLOC
, this->rela_irelative_
,
1581 ORDER_DYNAMIC_RELOCS
, false);
1582 gold_assert(this->rela_dyn_
->output_section()
1583 == this->rela_irelative_
->output_section());
1585 return this->rela_irelative_
;
1588 // Record a target-specific program property from the .note.gnu.property
1592 Target_x86_64
<size
>::record_gnu_property(
1593 unsigned int, unsigned int pr_type
,
1594 size_t pr_datasz
, const unsigned char* pr_data
,
1595 const Object
* object
)
1601 case elfcpp::GNU_PROPERTY_X86_COMPAT_ISA_1_USED
:
1602 case elfcpp::GNU_PROPERTY_X86_COMPAT_ISA_1_NEEDED
:
1603 case elfcpp::GNU_PROPERTY_X86_COMPAT_2_ISA_1_USED
:
1604 case elfcpp::GNU_PROPERTY_X86_COMPAT_2_ISA_1_NEEDED
:
1605 case elfcpp::GNU_PROPERTY_X86_ISA_1_USED
:
1606 case elfcpp::GNU_PROPERTY_X86_ISA_1_NEEDED
:
1607 case elfcpp::GNU_PROPERTY_X86_FEATURE_1_AND
:
1608 case elfcpp::GNU_PROPERTY_X86_FEATURE_2_USED
:
1609 case elfcpp::GNU_PROPERTY_X86_FEATURE_2_NEEDED
:
1612 gold_warning(_("%s: corrupt .note.gnu.property section "
1613 "(pr_datasz for property %d is not 4)"),
1614 object
->name().c_str(), pr_type
);
1617 val
= elfcpp::Swap
<32, false>::readval(pr_data
);
1620 gold_warning(_("%s: unknown program property type 0x%x "
1621 "in .note.gnu.property section"),
1622 object
->name().c_str(), pr_type
);
1628 case elfcpp::GNU_PROPERTY_X86_ISA_1_USED
:
1629 this->object_isa_1_used_
|= val
;
1631 case elfcpp::GNU_PROPERTY_X86_ISA_1_NEEDED
:
1632 this->isa_1_needed_
|= val
;
1634 case elfcpp::GNU_PROPERTY_X86_FEATURE_1_AND
:
1635 // If we see multiple feature props in one object, OR them together.
1636 this->object_feature_1_
|= val
;
1638 case elfcpp::GNU_PROPERTY_X86_FEATURE_2_USED
:
1639 this->object_feature_2_used_
|= val
;
1641 case elfcpp::GNU_PROPERTY_X86_FEATURE_2_NEEDED
:
1642 this->feature_2_needed_
|= val
;
1647 // Merge the target-specific program properties from the current object.
1650 Target_x86_64
<size
>::merge_gnu_properties(const Object
*)
1652 if (this->seen_first_object_
)
1654 // If any object is missing the ISA_1_USED property, we must omit
1655 // it from the output file.
1656 if (this->object_isa_1_used_
== 0)
1657 this->isa_1_used_
= 0;
1658 else if (this->isa_1_used_
!= 0)
1659 this->isa_1_used_
|= this->object_isa_1_used_
;
1660 this->feature_1_
&= this->object_feature_1_
;
1661 // If any object is missing the FEATURE_2_USED property, we must
1662 // omit it from the output file.
1663 if (this->object_feature_2_used_
== 0)
1664 this->feature_2_used_
= 0;
1665 else if (this->feature_2_used_
!= 0)
1666 this->feature_2_used_
|= this->object_feature_2_used_
;
1670 this->isa_1_used_
= this->object_isa_1_used_
;
1671 this->feature_1_
= this->object_feature_1_
;
1672 this->feature_2_used_
= this->object_feature_2_used_
;
1673 this->seen_first_object_
= true;
1675 this->object_isa_1_used_
= 0;
1676 this->object_feature_1_
= 0;
1677 this->object_feature_2_used_
= 0;
1681 add_property(Layout
* layout
, unsigned int pr_type
, uint32_t val
)
1683 unsigned char buf
[4];
1684 elfcpp::Swap
<32, false>::writeval(buf
, val
);
1685 layout
->add_gnu_property(elfcpp::NT_GNU_PROPERTY_TYPE_0
, pr_type
, 4, buf
);
1688 // Finalize the target-specific program properties and add them back to
1692 Target_x86_64
<size
>::do_finalize_gnu_properties(Layout
* layout
) const
1694 if (this->isa_1_used_
!= 0)
1695 add_property(layout
, elfcpp::GNU_PROPERTY_X86_ISA_1_USED
,
1697 if (this->isa_1_needed_
!= 0)
1698 add_property(layout
, elfcpp::GNU_PROPERTY_X86_ISA_1_NEEDED
,
1699 this->isa_1_needed_
);
1700 if (this->feature_1_
!= 0)
1701 add_property(layout
, elfcpp::GNU_PROPERTY_X86_FEATURE_1_AND
,
1703 if (this->feature_2_used_
!= 0)
1704 add_property(layout
, elfcpp::GNU_PROPERTY_X86_FEATURE_2_USED
,
1705 this->feature_2_used_
);
1706 if (this->feature_2_needed_
!= 0)
1707 add_property(layout
, elfcpp::GNU_PROPERTY_X86_FEATURE_2_NEEDED
,
1708 this->feature_2_needed_
);
1711 // Write the first three reserved words of the .got.plt section.
1712 // The remainder of the section is written while writing the PLT
1713 // in Output_data_plt_i386::do_write.
1716 Output_data_got_plt_x86_64::do_write(Output_file
* of
)
1718 // The first entry in the GOT is the address of the .dynamic section
1719 // aka the PT_DYNAMIC segment. The next two entries are reserved.
1720 // We saved space for them when we created the section in
1721 // Target_x86_64::got_section.
1722 const off_t got_file_offset
= this->offset();
1723 gold_assert(this->data_size() >= 24);
1724 unsigned char* const got_view
= of
->get_output_view(got_file_offset
, 24);
1725 Output_section
* dynamic
= this->layout_
->dynamic_section();
1726 uint64_t dynamic_addr
= dynamic
== NULL
? 0 : dynamic
->address();
1727 elfcpp::Swap
<64, false>::writeval(got_view
, dynamic_addr
);
1728 memset(got_view
+ 8, 0, 16);
1729 of
->write_output_view(got_file_offset
, 24, got_view
);
1732 // Initialize the PLT section.
1736 Output_data_plt_x86_64
<size
>::init(Layout
* layout
)
1738 this->rel_
= new Reloc_section(false);
1739 layout
->add_output_section_data(".rela.plt", elfcpp::SHT_RELA
,
1740 elfcpp::SHF_ALLOC
, this->rel_
,
1741 ORDER_DYNAMIC_PLT_RELOCS
, false);
1746 Output_data_plt_x86_64
<size
>::do_adjust_output_section(Output_section
* os
)
1748 os
->set_entsize(this->get_plt_entry_size());
1751 // Add an entry to the PLT.
1755 Output_data_plt_x86_64
<size
>::add_entry(Symbol_table
* symtab
, Layout
* layout
,
1758 gold_assert(!gsym
->has_plt_offset());
1760 unsigned int plt_index
;
1762 section_offset_type got_offset
;
1764 unsigned int* pcount
;
1765 unsigned int offset
;
1766 unsigned int reserved
;
1767 Output_section_data_build
* got
;
1768 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
1769 && gsym
->can_use_relative_reloc(false))
1771 pcount
= &this->irelative_count_
;
1774 got
= this->got_irelative_
;
1778 pcount
= &this->count_
;
1781 got
= this->got_plt_
;
1784 if (!this->is_data_size_valid())
1786 // Note that when setting the PLT offset for a non-IRELATIVE
1787 // entry we skip the initial reserved PLT entry.
1788 plt_index
= *pcount
+ offset
;
1789 plt_offset
= plt_index
* this->get_plt_entry_size();
1793 got_offset
= (plt_index
- offset
+ reserved
) * 8;
1794 gold_assert(got_offset
== got
->current_data_size());
1796 // Every PLT entry needs a GOT entry which points back to the PLT
1797 // entry (this will be changed by the dynamic linker, normally
1798 // lazily when the function is called).
1799 got
->set_current_data_size(got_offset
+ 8);
1803 // FIXME: This is probably not correct for IRELATIVE relocs.
1805 // For incremental updates, find an available slot.
1806 plt_offset
= this->free_list_
.allocate(this->get_plt_entry_size(),
1807 this->get_plt_entry_size(), 0);
1808 if (plt_offset
== -1)
1809 gold_fallback(_("out of patch space (PLT);"
1810 " relink with --incremental-full"));
1812 // The GOT and PLT entries have a 1-1 correspondance, so the GOT offset
1813 // can be calculated from the PLT index, adjusting for the three
1814 // reserved entries at the beginning of the GOT.
1815 plt_index
= plt_offset
/ this->get_plt_entry_size() - 1;
1816 got_offset
= (plt_index
- offset
+ reserved
) * 8;
1819 gsym
->set_plt_offset(plt_offset
);
1821 // Every PLT entry needs a reloc.
1822 this->add_relocation(symtab
, layout
, gsym
, got_offset
);
1824 // Note that we don't need to save the symbol. The contents of the
1825 // PLT are independent of which symbols are used. The symbols only
1826 // appear in the relocations.
1829 // Add an entry to the PLT for a local STT_GNU_IFUNC symbol. Return
1834 Output_data_plt_x86_64
<size
>::add_local_ifunc_entry(
1835 Symbol_table
* symtab
,
1837 Sized_relobj_file
<size
, false>* relobj
,
1838 unsigned int local_sym_index
)
1840 unsigned int plt_offset
= this->irelative_count_
* this->get_plt_entry_size();
1841 ++this->irelative_count_
;
1843 section_offset_type got_offset
= this->got_irelative_
->current_data_size();
1845 // Every PLT entry needs a GOT entry which points back to the PLT
1847 this->got_irelative_
->set_current_data_size(got_offset
+ 8);
1849 // Every PLT entry needs a reloc.
1850 Reloc_section
* rela
= this->rela_irelative(symtab
, layout
);
1851 rela
->add_symbolless_local_addend(relobj
, local_sym_index
,
1852 elfcpp::R_X86_64_IRELATIVE
,
1853 this->got_irelative_
, got_offset
, 0);
1858 // Add the relocation for a PLT entry.
1862 Output_data_plt_x86_64
<size
>::add_relocation(Symbol_table
* symtab
,
1865 unsigned int got_offset
)
1867 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
1868 && gsym
->can_use_relative_reloc(false))
1870 Reloc_section
* rela
= this->rela_irelative(symtab
, layout
);
1871 rela
->add_symbolless_global_addend(gsym
, elfcpp::R_X86_64_IRELATIVE
,
1872 this->got_irelative_
, got_offset
, 0);
1876 gsym
->set_needs_dynsym_entry();
1877 this->rel_
->add_global(gsym
, elfcpp::R_X86_64_JUMP_SLOT
, this->got_plt_
,
1882 // Return where the TLSDESC relocations should go, creating it if
1883 // necessary. These follow the JUMP_SLOT relocations.
1886 typename Output_data_plt_x86_64
<size
>::Reloc_section
*
1887 Output_data_plt_x86_64
<size
>::rela_tlsdesc(Layout
* layout
)
1889 if (this->tlsdesc_rel_
== NULL
)
1891 this->tlsdesc_rel_
= new Reloc_section(false);
1892 layout
->add_output_section_data(".rela.plt", elfcpp::SHT_RELA
,
1893 elfcpp::SHF_ALLOC
, this->tlsdesc_rel_
,
1894 ORDER_DYNAMIC_PLT_RELOCS
, false);
1895 gold_assert(this->tlsdesc_rel_
->output_section()
1896 == this->rel_
->output_section());
1898 return this->tlsdesc_rel_
;
1901 // Return where the IRELATIVE relocations should go in the PLT. These
1902 // follow the JUMP_SLOT and the TLSDESC relocations.
1905 typename Output_data_plt_x86_64
<size
>::Reloc_section
*
1906 Output_data_plt_x86_64
<size
>::rela_irelative(Symbol_table
* symtab
,
1909 if (this->irelative_rel_
== NULL
)
1911 // Make sure we have a place for the TLSDESC relocations, in
1912 // case we see any later on.
1913 this->rela_tlsdesc(layout
);
1914 this->irelative_rel_
= new Reloc_section(false);
1915 layout
->add_output_section_data(".rela.plt", elfcpp::SHT_RELA
,
1916 elfcpp::SHF_ALLOC
, this->irelative_rel_
,
1917 ORDER_DYNAMIC_PLT_RELOCS
, false);
1918 gold_assert(this->irelative_rel_
->output_section()
1919 == this->rel_
->output_section());
1921 if (parameters
->doing_static_link())
1923 // A statically linked executable will only have a .rela.plt
1924 // section to hold R_X86_64_IRELATIVE relocs for
1925 // STT_GNU_IFUNC symbols. The library will use these
1926 // symbols to locate the IRELATIVE relocs at program startup
1928 symtab
->define_in_output_data("__rela_iplt_start", NULL
,
1929 Symbol_table::PREDEFINED
,
1930 this->irelative_rel_
, 0, 0,
1931 elfcpp::STT_NOTYPE
, elfcpp::STB_GLOBAL
,
1932 elfcpp::STV_HIDDEN
, 0, false, true);
1933 symtab
->define_in_output_data("__rela_iplt_end", NULL
,
1934 Symbol_table::PREDEFINED
,
1935 this->irelative_rel_
, 0, 0,
1936 elfcpp::STT_NOTYPE
, elfcpp::STB_GLOBAL
,
1937 elfcpp::STV_HIDDEN
, 0, true, true);
1940 return this->irelative_rel_
;
1943 // Return the PLT address to use for a global symbol.
1947 Output_data_plt_x86_64
<size
>::do_address_for_global(const Symbol
* gsym
)
1949 uint64_t offset
= 0;
1950 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
1951 && gsym
->can_use_relative_reloc(false))
1952 offset
= (this->count_
+ 1) * this->get_plt_entry_size();
1953 return this->address() + offset
+ gsym
->plt_offset();
1956 // Return the PLT address to use for a local symbol. These are always
1957 // IRELATIVE relocs.
1961 Output_data_plt_x86_64
<size
>::do_address_for_local(const Relobj
* object
,
1964 return (this->address()
1965 + (this->count_
+ 1) * this->get_plt_entry_size()
1966 + object
->local_plt_offset(r_sym
));
1969 // Set the final size.
1972 Output_data_plt_x86_64
<size
>::set_final_data_size()
1974 // Number of regular and IFUNC PLT entries, plus the first entry.
1975 unsigned int count
= this->count_
+ this->irelative_count_
+ 1;
1976 // Count the TLSDESC entry, if present.
1977 if (this->has_tlsdesc_entry())
1979 this->set_data_size(count
* this->get_plt_entry_size());
1982 // The first entry in the PLT for an executable.
1986 Output_data_plt_x86_64_standard
<size
>::first_plt_entry
[plt_entry_size
] =
1988 // From AMD64 ABI Draft 0.98, page 76
1989 0xff, 0x35, // pushq contents of memory address
1990 0, 0, 0, 0, // replaced with address of .got + 8
1991 0xff, 0x25, // jmp indirect
1992 0, 0, 0, 0, // replaced with address of .got + 16
1993 0x90, 0x90, 0x90, 0x90 // noop (x4)
1998 Output_data_plt_x86_64_standard
<size
>::do_fill_first_plt_entry(
2000 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
2001 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
)
2003 memcpy(pov
, first_plt_entry
, plt_entry_size
);
2004 // We do a jmp relative to the PC at the end of this instruction.
2005 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
2007 - (plt_address
+ 6)));
2008 elfcpp::Swap
<32, false>::writeval(pov
+ 8,
2010 - (plt_address
+ 12)));
2013 // Subsequent entries in the PLT for an executable.
2017 Output_data_plt_x86_64_standard
<size
>::plt_entry
[plt_entry_size
] =
2019 // From AMD64 ABI Draft 0.98, page 76
2020 0xff, 0x25, // jmpq indirect
2021 0, 0, 0, 0, // replaced with address of symbol in .got
2022 0x68, // pushq immediate
2023 0, 0, 0, 0, // replaced with offset into relocation table
2024 0xe9, // jmpq relative
2025 0, 0, 0, 0 // replaced with offset to start of .plt
2030 Output_data_plt_x86_64_standard
<size
>::do_fill_plt_entry(
2032 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
2033 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
2034 unsigned int got_offset
,
2035 unsigned int plt_offset
,
2036 unsigned int plt_index
)
2038 // Check PC-relative offset overflow in PLT entry.
2039 uint64_t plt_got_pcrel_offset
= (got_address
+ got_offset
2040 - (plt_address
+ plt_offset
+ 6));
2041 if (Bits
<32>::has_overflow(plt_got_pcrel_offset
))
2042 gold_error(_("PC-relative offset overflow in PLT entry %d"),
2045 memcpy(pov
, plt_entry
, plt_entry_size
);
2046 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
2047 plt_got_pcrel_offset
);
2049 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 7, plt_index
);
2050 elfcpp::Swap
<32, false>::writeval(pov
+ 12,
2051 - (plt_offset
+ plt_entry_size
));
2056 // The reserved TLSDESC entry in the PLT for an executable.
2060 Output_data_plt_x86_64_standard
<size
>::tlsdesc_plt_entry
[plt_entry_size
] =
2062 // From Alexandre Oliva, "Thread-Local Storage Descriptors for IA32
2063 // and AMD64/EM64T", Version 0.9.4 (2005-10-10).
2064 0xff, 0x35, // pushq x(%rip)
2065 0, 0, 0, 0, // replaced with address of linkmap GOT entry (at PLTGOT + 8)
2066 0xff, 0x25, // jmpq *y(%rip)
2067 0, 0, 0, 0, // replaced with offset of reserved TLSDESC_GOT entry
2074 Output_data_plt_x86_64_standard
<size
>::do_fill_tlsdesc_entry(
2076 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
2077 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
2078 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_base
,
2079 unsigned int tlsdesc_got_offset
,
2080 unsigned int plt_offset
)
2082 memcpy(pov
, tlsdesc_plt_entry
, plt_entry_size
);
2083 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
2085 - (plt_address
+ plt_offset
2087 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 8,
2089 + tlsdesc_got_offset
2090 - (plt_address
+ plt_offset
2094 // Return the APLT address to use for a global symbol (for -z bndplt).
2097 Output_data_plt_x86_64_bnd::do_address_for_global(const Symbol
* gsym
)
2099 uint64_t offset
= this->aplt_offset_
;
2100 // Convert the PLT offset into an APLT offset.
2101 unsigned int plt_offset
= gsym
->plt_offset();
2102 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
2103 && gsym
->can_use_relative_reloc(false))
2104 offset
+= this->regular_count() * aplt_entry_size
;
2106 plt_offset
-= plt_entry_size
;
2107 plt_offset
= plt_offset
/ (plt_entry_size
/ aplt_entry_size
);
2108 return this->address() + offset
+ plt_offset
;
2111 // Return the PLT address to use for a local symbol. These are always
2112 // IRELATIVE relocs.
2115 Output_data_plt_x86_64_bnd::do_address_for_local(const Relobj
* object
,
2118 // Convert the PLT offset into an APLT offset.
2119 const Sized_relobj_file
<64, false>* sized_relobj
=
2120 static_cast<const Sized_relobj_file
<64, false>*>(object
);
2121 const Symbol_value
<64>* psymval
= sized_relobj
->local_symbol(r_sym
);
2122 unsigned int plt_offset
= ((object
->local_plt_offset(r_sym
)
2123 - (psymval
->is_ifunc_symbol()
2124 ? 0 : plt_entry_size
))
2125 / (plt_entry_size
/ aplt_entry_size
));
2126 return (this->address()
2127 + this->aplt_offset_
2128 + this->regular_count() * aplt_entry_size
2132 // Set the final size.
2134 Output_data_plt_x86_64_bnd::set_final_data_size()
2136 // Number of regular and IFUNC PLT entries.
2137 unsigned int count
= this->entry_count();
2138 // Count the first entry and the TLSDESC entry, if present.
2139 unsigned int extra
= this->has_tlsdesc_entry() ? 2 : 1;
2140 unsigned int plt_size
= (count
+ extra
) * plt_entry_size
;
2141 // Offset of the APLT.
2142 this->aplt_offset_
= plt_size
;
2143 // Size of the APLT.
2144 plt_size
+= count
* aplt_entry_size
;
2145 this->set_data_size(plt_size
);
2148 // The first entry in the BND PLT.
2151 Output_data_plt_x86_64_bnd::first_plt_entry
[plt_entry_size
] =
2153 // From AMD64 ABI Draft 0.98, page 76
2154 0xff, 0x35, // pushq contents of memory address
2155 0, 0, 0, 0, // replaced with address of .got + 8
2156 0xf2, 0xff, 0x25, // bnd jmp indirect
2157 0, 0, 0, 0, // replaced with address of .got + 16
2158 0x0f, 0x1f, 0x00 // nop
2162 Output_data_plt_x86_64_bnd::do_fill_first_plt_entry(
2164 elfcpp::Elf_types
<64>::Elf_Addr got_address
,
2165 elfcpp::Elf_types
<64>::Elf_Addr plt_address
)
2167 memcpy(pov
, first_plt_entry
, plt_entry_size
);
2168 // We do a jmp relative to the PC at the end of this instruction.
2169 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
2171 - (plt_address
+ 6)));
2172 elfcpp::Swap
<32, false>::writeval(pov
+ 9,
2174 - (plt_address
+ 13)));
2177 // Subsequent entries in the BND PLT.
2180 Output_data_plt_x86_64_bnd::plt_entry
[plt_entry_size
] =
2182 // From AMD64 ABI Draft 0.99.8, page 139
2183 0x68, // pushq immediate
2184 0, 0, 0, 0, // replaced with offset into relocation table
2185 0xf2, 0xe9, // bnd jmpq relative
2186 0, 0, 0, 0, // replaced with offset to start of .plt
2187 0x0f, 0x1f, 0x44, 0, 0 // nop
2190 // Entries in the BND Additional PLT.
2193 Output_data_plt_x86_64_bnd::aplt_entry
[aplt_entry_size
] =
2195 // From AMD64 ABI Draft 0.99.8, page 139
2196 0xf2, 0xff, 0x25, // bnd jmpq indirect
2197 0, 0, 0, 0, // replaced with address of symbol in .got
2202 Output_data_plt_x86_64_bnd::do_fill_plt_entry(
2204 elfcpp::Elf_types
<64>::Elf_Addr
,
2205 elfcpp::Elf_types
<64>::Elf_Addr
,
2207 unsigned int plt_offset
,
2208 unsigned int plt_index
)
2210 memcpy(pov
, plt_entry
, plt_entry_size
);
2211 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 1, plt_index
);
2212 elfcpp::Swap
<32, false>::writeval(pov
+ 7, -(plt_offset
+ 11));
2217 Output_data_plt_x86_64_bnd::fill_aplt_entry(
2219 elfcpp::Elf_types
<64>::Elf_Addr got_address
,
2220 elfcpp::Elf_types
<64>::Elf_Addr plt_address
,
2221 unsigned int got_offset
,
2222 unsigned int plt_offset
,
2223 unsigned int plt_index
)
2225 // Check PC-relative offset overflow in PLT entry.
2226 uint64_t plt_got_pcrel_offset
= (got_address
+ got_offset
2227 - (plt_address
+ plt_offset
+ 7));
2228 if (Bits
<32>::has_overflow(plt_got_pcrel_offset
))
2229 gold_error(_("PC-relative offset overflow in APLT entry %d"),
2232 memcpy(pov
, aplt_entry
, aplt_entry_size
);
2233 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 3, plt_got_pcrel_offset
);
2236 // The reserved TLSDESC entry in the PLT for an executable.
2239 Output_data_plt_x86_64_bnd::tlsdesc_plt_entry
[plt_entry_size
] =
2241 // From Alexandre Oliva, "Thread-Local Storage Descriptors for IA32
2242 // and AMD64/EM64T", Version 0.9.4 (2005-10-10).
2243 0xff, 0x35, // pushq x(%rip)
2244 0, 0, 0, 0, // replaced with address of linkmap GOT entry (at PLTGOT + 8)
2245 0xf2, 0xff, 0x25, // jmpq *y(%rip)
2246 0, 0, 0, 0, // replaced with offset of reserved TLSDESC_GOT entry
2247 0x0f, 0x1f, 0 // nop
2251 Output_data_plt_x86_64_bnd::do_fill_tlsdesc_entry(
2253 elfcpp::Elf_types
<64>::Elf_Addr got_address
,
2254 elfcpp::Elf_types
<64>::Elf_Addr plt_address
,
2255 elfcpp::Elf_types
<64>::Elf_Addr got_base
,
2256 unsigned int tlsdesc_got_offset
,
2257 unsigned int plt_offset
)
2259 memcpy(pov
, tlsdesc_plt_entry
, plt_entry_size
);
2260 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
2262 - (plt_address
+ plt_offset
2264 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 9,
2266 + tlsdesc_got_offset
2267 - (plt_address
+ plt_offset
2271 // Return the APLT address to use for a global symbol (for IBT).
2275 Output_data_plt_x86_64_ibt
<size
>::do_address_for_global(const Symbol
* gsym
)
2277 uint64_t offset
= this->aplt_offset_
;
2278 // Convert the PLT offset into an APLT offset.
2279 unsigned int plt_offset
= gsym
->plt_offset();
2280 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
2281 && gsym
->can_use_relative_reloc(false))
2282 offset
+= this->regular_count() * aplt_entry_size
;
2284 plt_offset
-= plt_entry_size
;
2285 plt_offset
= plt_offset
/ (plt_entry_size
/ aplt_entry_size
);
2286 return this->address() + offset
+ plt_offset
;
2289 // Return the PLT address to use for a local symbol. These are always
2290 // IRELATIVE relocs.
2294 Output_data_plt_x86_64_ibt
<size
>::do_address_for_local(const Relobj
* object
,
2297 // Convert the PLT offset into an APLT offset.
2298 const Sized_relobj_file
<size
, false>* sized_relobj
=
2299 static_cast<const Sized_relobj_file
<size
, false>*>(object
);
2300 const Symbol_value
<size
>* psymval
= sized_relobj
->local_symbol(r_sym
);
2301 unsigned int plt_offset
= ((object
->local_plt_offset(r_sym
)
2302 - (psymval
->is_ifunc_symbol()
2303 ? 0 : plt_entry_size
))
2304 / (plt_entry_size
/ aplt_entry_size
));
2305 return (this->address()
2306 + this->aplt_offset_
2307 + this->regular_count() * aplt_entry_size
2311 // Set the final size.
2315 Output_data_plt_x86_64_ibt
<size
>::set_final_data_size()
2317 // Number of regular and IFUNC PLT entries.
2318 unsigned int count
= this->entry_count();
2319 // Count the first entry and the TLSDESC entry, if present.
2320 unsigned int extra
= this->has_tlsdesc_entry() ? 2 : 1;
2321 unsigned int plt_size
= (count
+ extra
) * plt_entry_size
;
2322 // Offset of the APLT.
2323 this->aplt_offset_
= plt_size
;
2324 // Size of the APLT.
2325 plt_size
+= count
* aplt_entry_size
;
2326 this->set_data_size(plt_size
);
2329 // The first entry in the IBT PLT.
2333 Output_data_plt_x86_64_ibt
<32>::first_plt_entry
[plt_entry_size
] =
2335 // MPX isn't supported for x32, so we don't need the BND prefix.
2336 // From AMD64 ABI Draft 0.98, page 76
2337 0xff, 0x35, // pushq contents of memory address
2338 0, 0, 0, 0, // replaced with address of .got + 8
2339 0xff, 0x25, // jmp indirect
2340 0, 0, 0, 0, // replaced with address of .got + 16
2341 0x90, 0x90, 0x90, 0x90 // noop (x4)
2346 Output_data_plt_x86_64_ibt
<64>::first_plt_entry
[plt_entry_size
] =
2348 // Use the BND prefix so that IBT is compatible with MPX.
2349 0xff, 0x35, // pushq contents of memory address
2350 0, 0, 0, 0, // replaced with address of .got + 8
2351 0xf2, 0xff, 0x25, // bnd jmp indirect
2352 0, 0, 0, 0, // replaced with address of .got + 16
2353 0x0f, 0x1f, 0x00 // nop
2358 Output_data_plt_x86_64_ibt
<size
>::do_fill_first_plt_entry(
2360 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
2361 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
)
2363 // Offsets to the addresses needing relocation.
2364 const unsigned int roff1
= 2;
2365 const unsigned int roff2
= (size
== 32) ? 8 : 9;
2367 memcpy(pov
, first_plt_entry
, plt_entry_size
);
2368 // We do a jmp relative to the PC at the end of this instruction.
2369 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ roff1
,
2371 - (plt_address
+ roff1
+ 4)));
2372 elfcpp::Swap
<32, false>::writeval(pov
+ roff2
,
2374 - (plt_address
+ roff2
+ 4)));
2377 // Subsequent entries in the IBT PLT.
2381 Output_data_plt_x86_64_ibt
<32>::plt_entry
[plt_entry_size
] =
2383 // From AMD64 ABI Draft 1.0-rc1, Chapter 13.
2384 0xf3, 0x0f, 0x1e, 0xfa, // endbr64
2385 0x68, // pushq immediate
2386 0, 0, 0, 0, // replaced with offset into relocation table
2387 0xe9, // jmpq relative
2388 0, 0, 0, 0, // replaced with offset to start of .plt
2394 Output_data_plt_x86_64_ibt
<64>::plt_entry
[plt_entry_size
] =
2396 // From AMD64 ABI Draft 1.0-rc1, Chapter 13.
2397 0xf3, 0x0f, 0x1e, 0xfa, // endbr64
2398 0x68, // pushq immediate
2399 0, 0, 0, 0, // replaced with offset into relocation table
2400 0xf2, 0xe9, // bnd jmpq relative
2401 0, 0, 0, 0, // replaced with offset to start of .plt
2405 // Entries in the IBT Additional PLT.
2409 Output_data_plt_x86_64_ibt
<32>::aplt_entry
[aplt_entry_size
] =
2411 // From AMD64 ABI Draft 1.0-rc1, Chapter 13.
2412 0xf3, 0x0f, 0x1e, 0xfa, // endbr64
2413 0xff, 0x25, // jmpq indirect
2414 0, 0, 0, 0, // replaced with address of symbol in .got
2415 0x0f, 0x1f, 0x04, 0x00, // nop
2421 Output_data_plt_x86_64_ibt
<64>::aplt_entry
[aplt_entry_size
] =
2423 // From AMD64 ABI Draft 1.0-rc1, Chapter 13.
2424 0xf3, 0x0f, 0x1e, 0xfa, // endbr64
2425 0xf2, 0xff, 0x25, // bnd jmpq indirect
2426 0, 0, 0, 0, // replaced with address of symbol in .got
2427 0x0f, 0x1f, 0x04, 0x00, // nop
2433 Output_data_plt_x86_64_ibt
<size
>::do_fill_plt_entry(
2435 typename
elfcpp::Elf_types
<size
>::Elf_Addr
,
2436 typename
elfcpp::Elf_types
<size
>::Elf_Addr
,
2438 unsigned int plt_offset
,
2439 unsigned int plt_index
)
2441 // Offsets to the addresses needing relocation.
2442 const unsigned int roff1
= 5;
2443 const unsigned int roff2
= (size
== 32) ? 10 : 11;
2445 memcpy(pov
, plt_entry
, plt_entry_size
);
2446 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ roff1
, plt_index
);
2447 elfcpp::Swap
<32, false>::writeval(pov
+ roff2
, -(plt_offset
+ roff2
+ 4));
2453 Output_data_plt_x86_64_ibt
<size
>::fill_aplt_entry(
2455 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
2456 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
2457 unsigned int got_offset
,
2458 unsigned int plt_offset
,
2459 unsigned int plt_index
)
2461 // Offset to the address needing relocation.
2462 const unsigned int roff
= (size
== 32) ? 6 : 7;
2464 // Check PC-relative offset overflow in PLT entry.
2465 uint64_t plt_got_pcrel_offset
= (got_address
+ got_offset
2466 - (plt_address
+ plt_offset
+ roff
+ 4));
2467 if (Bits
<32>::has_overflow(plt_got_pcrel_offset
))
2468 gold_error(_("PC-relative offset overflow in APLT entry %d"),
2471 memcpy(pov
, aplt_entry
, aplt_entry_size
);
2472 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ roff
, plt_got_pcrel_offset
);
2475 // The reserved TLSDESC entry in the IBT PLT for an executable.
2479 Output_data_plt_x86_64_ibt
<size
>::tlsdesc_plt_entry
[plt_entry_size
] =
2481 // From Alexandre Oliva, "Thread-Local Storage Descriptors for IA32
2482 // and AMD64/EM64T", Version 0.9.4 (2005-10-10).
2483 0xf3, 0x0f, 0x1e, 0xfa, // endbr64
2484 0xff, 0x35, // pushq x(%rip)
2485 0, 0, 0, 0, // replaced with address of linkmap GOT entry (at PLTGOT + 8)
2486 0xff, 0x25, // jmpq *y(%rip)
2487 0, 0, 0, 0, // replaced with offset of reserved TLSDESC_GOT entry
2492 Output_data_plt_x86_64_ibt
<size
>::do_fill_tlsdesc_entry(
2494 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
2495 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
2496 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_base
,
2497 unsigned int tlsdesc_got_offset
,
2498 unsigned int plt_offset
)
2500 memcpy(pov
, tlsdesc_plt_entry
, plt_entry_size
);
2501 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 6,
2503 - (plt_address
+ plt_offset
2505 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 12,
2507 + tlsdesc_got_offset
2508 - (plt_address
+ plt_offset
2512 // The .eh_frame unwind information for the PLT.
2516 Output_data_plt_x86_64
<size
>::plt_eh_frame_cie
[plt_eh_frame_cie_size
] =
2519 'z', // Augmentation: augmentation size included.
2520 'R', // Augmentation: FDE encoding included.
2521 '\0', // End of augmentation string.
2522 1, // Code alignment factor.
2523 0x78, // Data alignment factor.
2524 16, // Return address column.
2525 1, // Augmentation size.
2526 (elfcpp::DW_EH_PE_pcrel
// FDE encoding.
2527 | elfcpp::DW_EH_PE_sdata4
),
2528 elfcpp::DW_CFA_def_cfa
, 7, 8, // DW_CFA_def_cfa: r7 (rsp) ofs 8.
2529 elfcpp::DW_CFA_offset
+ 16, 1,// DW_CFA_offset: r16 (rip) at cfa-8.
2530 elfcpp::DW_CFA_nop
, // Align to 16 bytes.
2536 Output_data_plt_x86_64_standard
<size
>::plt_eh_frame_fde
[plt_eh_frame_fde_size
] =
2538 0, 0, 0, 0, // Replaced with offset to .plt.
2539 0, 0, 0, 0, // Replaced with size of .plt.
2540 0, // Augmentation size.
2541 elfcpp::DW_CFA_def_cfa_offset
, 16, // DW_CFA_def_cfa_offset: 16.
2542 elfcpp::DW_CFA_advance_loc
+ 6, // Advance 6 to __PLT__ + 6.
2543 elfcpp::DW_CFA_def_cfa_offset
, 24, // DW_CFA_def_cfa_offset: 24.
2544 elfcpp::DW_CFA_advance_loc
+ 10, // Advance 10 to __PLT__ + 16.
2545 elfcpp::DW_CFA_def_cfa_expression
, // DW_CFA_def_cfa_expression.
2546 11, // Block length.
2547 elfcpp::DW_OP_breg7
, 8, // Push %rsp + 8.
2548 elfcpp::DW_OP_breg16
, 0, // Push %rip.
2549 elfcpp::DW_OP_lit15
, // Push 0xf.
2550 elfcpp::DW_OP_and
, // & (%rip & 0xf).
2551 elfcpp::DW_OP_lit11
, // Push 0xb.
2552 elfcpp::DW_OP_ge
, // >= ((%rip & 0xf) >= 0xb)
2553 elfcpp::DW_OP_lit3
, // Push 3.
2554 elfcpp::DW_OP_shl
, // << (((%rip & 0xf) >= 0xb) << 3)
2555 elfcpp::DW_OP_plus
, // + ((((%rip&0xf)>=0xb)<<3)+%rsp+8
2556 elfcpp::DW_CFA_nop
, // Align to 32 bytes.
2562 // The .eh_frame unwind information for the BND PLT.
2564 Output_data_plt_x86_64_bnd::plt_eh_frame_fde
[plt_eh_frame_fde_size
] =
2566 0, 0, 0, 0, // Replaced with offset to .plt.
2567 0, 0, 0, 0, // Replaced with size of .plt.
2568 0, // Augmentation size.
2569 elfcpp::DW_CFA_def_cfa_offset
, 16, // DW_CFA_def_cfa_offset: 16.
2570 elfcpp::DW_CFA_advance_loc
+ 6, // Advance 6 to __PLT__ + 6.
2571 elfcpp::DW_CFA_def_cfa_offset
, 24, // DW_CFA_def_cfa_offset: 24.
2572 elfcpp::DW_CFA_advance_loc
+ 10, // Advance 10 to __PLT__ + 16.
2573 elfcpp::DW_CFA_def_cfa_expression
, // DW_CFA_def_cfa_expression.
2574 11, // Block length.
2575 elfcpp::DW_OP_breg7
, 8, // Push %rsp + 8.
2576 elfcpp::DW_OP_breg16
, 0, // Push %rip.
2577 elfcpp::DW_OP_lit15
, // Push 0xf.
2578 elfcpp::DW_OP_and
, // & (%rip & 0xf).
2579 elfcpp::DW_OP_lit5
, // Push 5.
2580 elfcpp::DW_OP_ge
, // >= ((%rip & 0xf) >= 5)
2581 elfcpp::DW_OP_lit3
, // Push 3.
2582 elfcpp::DW_OP_shl
, // << (((%rip & 0xf) >= 5) << 3)
2583 elfcpp::DW_OP_plus
, // + ((((%rip&0xf)>=5)<<3)+%rsp+8
2584 elfcpp::DW_CFA_nop
, // Align to 32 bytes.
2590 // The .eh_frame unwind information for the BND PLT.
2593 Output_data_plt_x86_64_ibt
<size
>::plt_eh_frame_fde
[plt_eh_frame_fde_size
] =
2595 0, 0, 0, 0, // Replaced with offset to .plt.
2596 0, 0, 0, 0, // Replaced with size of .plt.
2597 0, // Augmentation size.
2598 elfcpp::DW_CFA_def_cfa_offset
, 16, // DW_CFA_def_cfa_offset: 16.
2599 elfcpp::DW_CFA_advance_loc
+ 6, // Advance 6 to __PLT__ + 6.
2600 elfcpp::DW_CFA_def_cfa_offset
, 24, // DW_CFA_def_cfa_offset: 24.
2601 elfcpp::DW_CFA_advance_loc
+ 10, // Advance 10 to __PLT__ + 16.
2602 elfcpp::DW_CFA_def_cfa_expression
, // DW_CFA_def_cfa_expression.
2603 11, // Block length.
2604 elfcpp::DW_OP_breg7
, 8, // Push %rsp + 8.
2605 elfcpp::DW_OP_breg16
, 0, // Push %rip.
2606 elfcpp::DW_OP_lit15
, // Push 0xf.
2607 elfcpp::DW_OP_and
, // & (%rip & 0xf).
2608 elfcpp::DW_OP_lit9
, // Push 9.
2609 elfcpp::DW_OP_ge
, // >= ((%rip & 0xf) >= 9)
2610 elfcpp::DW_OP_lit3
, // Push 3.
2611 elfcpp::DW_OP_shl
, // << (((%rip & 0xf) >= 9) << 3)
2612 elfcpp::DW_OP_plus
, // + ((((%rip&0xf)>=9)<<3)+%rsp+8
2613 elfcpp::DW_CFA_nop
, // Align to 32 bytes.
2619 // Write out the PLT. This uses the hand-coded instructions above,
2620 // and adjusts them as needed. This is specified by the AMD64 ABI.
2624 Output_data_plt_x86_64
<size
>::do_write(Output_file
* of
)
2626 const off_t offset
= this->offset();
2627 const section_size_type oview_size
=
2628 convert_to_section_size_type(this->data_size());
2629 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
2631 const off_t got_file_offset
= this->got_plt_
->offset();
2632 gold_assert(parameters
->incremental_update()
2633 || (got_file_offset
+ this->got_plt_
->data_size()
2634 == this->got_irelative_
->offset()));
2635 const section_size_type got_size
=
2636 convert_to_section_size_type(this->got_plt_
->data_size()
2637 + this->got_irelative_
->data_size());
2638 unsigned char* const got_view
= of
->get_output_view(got_file_offset
,
2641 unsigned char* pov
= oview
;
2643 // The base address of the .plt section.
2644 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
= this->address();
2645 // The base address of the .got section.
2646 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_base
= this->got_
->address();
2647 // The base address of the PLT portion of the .got section,
2648 // which is where the GOT pointer will point, and where the
2649 // three reserved GOT entries are located.
2650 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
2651 = this->got_plt_
->address();
2653 this->fill_first_plt_entry(pov
, got_address
, plt_address
);
2654 pov
+= this->get_plt_entry_size();
2656 // The first three entries in the GOT are reserved, and are written
2657 // by Output_data_got_plt_x86_64::do_write.
2658 unsigned char* got_pov
= got_view
+ 24;
2660 unsigned int plt_offset
= this->get_plt_entry_size();
2661 unsigned int got_offset
= 24;
2662 const unsigned int count
= this->count_
+ this->irelative_count_
;
2663 for (unsigned int plt_index
= 0;
2666 pov
+= this->get_plt_entry_size(),
2668 plt_offset
+= this->get_plt_entry_size(),
2671 // Set and adjust the PLT entry itself.
2672 unsigned int lazy_offset
= this->fill_plt_entry(pov
,
2673 got_address
, plt_address
,
2674 got_offset
, plt_offset
,
2677 // Set the entry in the GOT.
2678 elfcpp::Swap
<64, false>::writeval(got_pov
,
2679 plt_address
+ plt_offset
+ lazy_offset
);
2682 if (this->has_tlsdesc_entry())
2684 // Set and adjust the reserved TLSDESC PLT entry.
2685 unsigned int tlsdesc_got_offset
= this->get_tlsdesc_got_offset();
2686 this->fill_tlsdesc_entry(pov
, got_address
, plt_address
, got_base
,
2687 tlsdesc_got_offset
, plt_offset
);
2688 pov
+= this->get_plt_entry_size();
2691 gold_assert(static_cast<section_size_type
>(pov
- oview
) == oview_size
);
2692 gold_assert(static_cast<section_size_type
>(got_pov
- got_view
) == got_size
);
2694 of
->write_output_view(offset
, oview_size
, oview
);
2695 of
->write_output_view(got_file_offset
, got_size
, got_view
);
2698 // Write out the BND PLT.
2701 Output_data_plt_x86_64_bnd::do_write(Output_file
* of
)
2703 const off_t offset
= this->offset();
2704 const section_size_type oview_size
=
2705 convert_to_section_size_type(this->data_size());
2706 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
2708 Output_data_got
<64, false>* got
= this->got();
2709 Output_data_got_plt_x86_64
* got_plt
= this->got_plt();
2710 Output_data_space
* got_irelative
= this->got_irelative();
2712 const off_t got_file_offset
= got_plt
->offset();
2713 gold_assert(parameters
->incremental_update()
2714 || (got_file_offset
+ got_plt
->data_size()
2715 == got_irelative
->offset()));
2716 const section_size_type got_size
=
2717 convert_to_section_size_type(got_plt
->data_size()
2718 + got_irelative
->data_size());
2719 unsigned char* const got_view
= of
->get_output_view(got_file_offset
,
2722 unsigned char* pov
= oview
;
2724 // The base address of the .plt section.
2725 elfcpp::Elf_types
<64>::Elf_Addr plt_address
= this->address();
2726 // The base address of the .got section.
2727 elfcpp::Elf_types
<64>::Elf_Addr got_base
= got
->address();
2728 // The base address of the PLT portion of the .got section,
2729 // which is where the GOT pointer will point, and where the
2730 // three reserved GOT entries are located.
2731 elfcpp::Elf_types
<64>::Elf_Addr got_address
= got_plt
->address();
2733 this->fill_first_plt_entry(pov
, got_address
, plt_address
);
2734 pov
+= plt_entry_size
;
2736 // The first three entries in the GOT are reserved, and are written
2737 // by Output_data_got_plt_x86_64::do_write.
2738 unsigned char* got_pov
= got_view
+ 24;
2740 unsigned int plt_offset
= plt_entry_size
;
2741 unsigned int got_offset
= 24;
2742 const unsigned int count
= this->entry_count();
2743 for (unsigned int plt_index
= 0;
2746 pov
+= plt_entry_size
,
2748 plt_offset
+= plt_entry_size
,
2751 // Set and adjust the PLT entry itself.
2752 unsigned int lazy_offset
= this->fill_plt_entry(pov
,
2753 got_address
, plt_address
,
2754 got_offset
, plt_offset
,
2757 // Set the entry in the GOT.
2758 elfcpp::Swap
<64, false>::writeval(got_pov
,
2759 plt_address
+ plt_offset
+ lazy_offset
);
2762 if (this->has_tlsdesc_entry())
2764 // Set and adjust the reserved TLSDESC PLT entry.
2765 unsigned int tlsdesc_got_offset
= this->get_tlsdesc_got_offset();
2766 this->fill_tlsdesc_entry(pov
, got_address
, plt_address
, got_base
,
2767 tlsdesc_got_offset
, plt_offset
);
2768 pov
+= this->get_plt_entry_size();
2769 plt_offset
+= plt_entry_size
;
2772 // Write the additional PLT.
2774 for (unsigned int plt_index
= 0;
2777 pov
+= aplt_entry_size
,
2778 plt_offset
+= aplt_entry_size
,
2781 // Set and adjust the APLT entry.
2782 this->fill_aplt_entry(pov
, got_address
, plt_address
, got_offset
,
2783 plt_offset
, plt_index
);
2786 gold_assert(static_cast<section_size_type
>(pov
- oview
) == oview_size
);
2787 gold_assert(static_cast<section_size_type
>(got_pov
- got_view
) == got_size
);
2789 of
->write_output_view(offset
, oview_size
, oview
);
2790 of
->write_output_view(got_file_offset
, got_size
, got_view
);
2793 // Write out the IBT PLT.
2797 Output_data_plt_x86_64_ibt
<size
>::do_write(Output_file
* of
)
2799 const off_t offset
= this->offset();
2800 const section_size_type oview_size
=
2801 convert_to_section_size_type(this->data_size());
2802 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
2804 Output_data_got
<64, false>* got
= this->got();
2805 Output_data_got_plt_x86_64
* got_plt
= this->got_plt();
2806 Output_data_space
* got_irelative
= this->got_irelative();
2808 const off_t got_file_offset
= got_plt
->offset();
2809 gold_assert(parameters
->incremental_update()
2810 || (got_file_offset
+ got_plt
->data_size()
2811 == got_irelative
->offset()));
2812 const section_size_type got_size
=
2813 convert_to_section_size_type(got_plt
->data_size()
2814 + got_irelative
->data_size());
2815 unsigned char* const got_view
= of
->get_output_view(got_file_offset
,
2818 unsigned char* pov
= oview
;
2820 // The base address of the .plt section.
2821 elfcpp::Elf_types
<64>::Elf_Addr plt_address
= this->address();
2822 // The base address of the .got section.
2823 elfcpp::Elf_types
<64>::Elf_Addr got_base
= got
->address();
2824 // The base address of the PLT portion of the .got section,
2825 // which is where the GOT pointer will point, and where the
2826 // three reserved GOT entries are located.
2827 elfcpp::Elf_types
<64>::Elf_Addr got_address
= got_plt
->address();
2829 this->fill_first_plt_entry(pov
, got_address
, plt_address
);
2830 pov
+= plt_entry_size
;
2832 // The first three entries in the GOT are reserved, and are written
2833 // by Output_data_got_plt_x86_64::do_write.
2834 unsigned char* got_pov
= got_view
+ 24;
2836 unsigned int plt_offset
= plt_entry_size
;
2837 unsigned int got_offset
= 24;
2838 const unsigned int count
= this->entry_count();
2839 for (unsigned int plt_index
= 0;
2842 pov
+= plt_entry_size
,
2844 plt_offset
+= plt_entry_size
,
2847 // Set and adjust the PLT entry itself.
2848 unsigned int lazy_offset
= this->fill_plt_entry(pov
,
2849 got_address
, plt_address
,
2850 got_offset
, plt_offset
,
2853 // Set the entry in the GOT.
2854 elfcpp::Swap
<64, false>::writeval(got_pov
,
2855 plt_address
+ plt_offset
+ lazy_offset
);
2858 if (this->has_tlsdesc_entry())
2860 // Set and adjust the reserved TLSDESC PLT entry.
2861 unsigned int tlsdesc_got_offset
= this->get_tlsdesc_got_offset();
2862 this->fill_tlsdesc_entry(pov
, got_address
, plt_address
, got_base
,
2863 tlsdesc_got_offset
, plt_offset
);
2864 pov
+= this->get_plt_entry_size();
2865 plt_offset
+= plt_entry_size
;
2868 // Write the additional PLT.
2870 for (unsigned int plt_index
= 0;
2873 pov
+= aplt_entry_size
,
2874 plt_offset
+= aplt_entry_size
,
2877 // Set and adjust the APLT entry.
2878 this->fill_aplt_entry(pov
, got_address
, plt_address
, got_offset
,
2879 plt_offset
, plt_index
);
2882 gold_assert(static_cast<section_size_type
>(pov
- oview
) == oview_size
);
2883 gold_assert(static_cast<section_size_type
>(got_pov
- got_view
) == got_size
);
2885 of
->write_output_view(offset
, oview_size
, oview
);
2886 of
->write_output_view(got_file_offset
, got_size
, got_view
);
2889 // Create the PLT section.
2893 Target_x86_64
<size
>::make_plt_section(Symbol_table
* symtab
, Layout
* layout
)
2895 if (this->plt_
== NULL
)
2897 // Create the GOT sections first.
2898 this->got_section(symtab
, layout
);
2900 this->plt_
= this->make_data_plt(layout
, this->got_
, this->got_plt_
,
2901 this->got_irelative_
);
2903 // Add unwind information if requested.
2904 if (parameters
->options().ld_generated_unwind_info())
2905 this->plt_
->add_eh_frame(layout
);
2907 layout
->add_output_section_data(".plt", elfcpp::SHT_PROGBITS
,
2909 | elfcpp::SHF_EXECINSTR
),
2910 this->plt_
, ORDER_PLT
, false);
2912 // Make the sh_info field of .rela.plt point to .plt.
2913 Output_section
* rela_plt_os
= this->plt_
->rela_plt()->output_section();
2914 rela_plt_os
->set_info_section(this->plt_
->output_section());
2919 Output_data_plt_x86_64
<32>*
2920 Target_x86_64
<32>::do_make_data_plt(Layout
* layout
,
2921 Output_data_got
<64, false>* got
,
2922 Output_data_got_plt_x86_64
* got_plt
,
2923 Output_data_space
* got_irelative
)
2925 if (this->feature_1_
& elfcpp::GNU_PROPERTY_X86_FEATURE_1_IBT
)
2926 return new Output_data_plt_x86_64_ibt
<32>(layout
, got
, got_plt
,
2928 return new Output_data_plt_x86_64_standard
<32>(layout
, got
, got_plt
,
2933 Output_data_plt_x86_64
<64>*
2934 Target_x86_64
<64>::do_make_data_plt(Layout
* layout
,
2935 Output_data_got
<64, false>* got
,
2936 Output_data_got_plt_x86_64
* got_plt
,
2937 Output_data_space
* got_irelative
)
2939 if (this->feature_1_
& elfcpp::GNU_PROPERTY_X86_FEATURE_1_IBT
)
2940 return new Output_data_plt_x86_64_ibt
<64>(layout
, got
, got_plt
,
2942 else if (parameters
->options().bndplt())
2943 return new Output_data_plt_x86_64_bnd(layout
, got
, got_plt
,
2946 return new Output_data_plt_x86_64_standard
<64>(layout
, got
, got_plt
,
2951 Output_data_plt_x86_64
<32>*
2952 Target_x86_64
<32>::do_make_data_plt(Layout
* layout
,
2953 Output_data_got
<64, false>* got
,
2954 Output_data_got_plt_x86_64
* got_plt
,
2955 Output_data_space
* got_irelative
,
2956 unsigned int plt_count
)
2958 if (this->feature_1_
& elfcpp::GNU_PROPERTY_X86_FEATURE_1_IBT
)
2959 return new Output_data_plt_x86_64_ibt
<32>(layout
, got
, got_plt
,
2960 got_irelative
, plt_count
);
2961 return new Output_data_plt_x86_64_standard
<32>(layout
, got
, got_plt
,
2962 got_irelative
, plt_count
);
2966 Output_data_plt_x86_64
<64>*
2967 Target_x86_64
<64>::do_make_data_plt(Layout
* layout
,
2968 Output_data_got
<64, false>* got
,
2969 Output_data_got_plt_x86_64
* got_plt
,
2970 Output_data_space
* got_irelative
,
2971 unsigned int plt_count
)
2973 if (this->feature_1_
& elfcpp::GNU_PROPERTY_X86_FEATURE_1_IBT
)
2974 return new Output_data_plt_x86_64_ibt
<64>(layout
, got
, got_plt
,
2975 got_irelative
, plt_count
);
2976 else if (parameters
->options().bndplt())
2977 return new Output_data_plt_x86_64_bnd(layout
, got
, got_plt
,
2978 got_irelative
, plt_count
);
2980 return new Output_data_plt_x86_64_standard
<64>(layout
, got
, got_plt
,
2985 // Return the section for TLSDESC relocations.
2988 typename Target_x86_64
<size
>::Reloc_section
*
2989 Target_x86_64
<size
>::rela_tlsdesc_section(Layout
* layout
) const
2991 return this->plt_section()->rela_tlsdesc(layout
);
2994 // Create a PLT entry for a global symbol.
2998 Target_x86_64
<size
>::make_plt_entry(Symbol_table
* symtab
, Layout
* layout
,
3001 if (gsym
->has_plt_offset())
3004 if (this->plt_
== NULL
)
3005 this->make_plt_section(symtab
, layout
);
3007 this->plt_
->add_entry(symtab
, layout
, gsym
);
3010 // Make a PLT entry for a local STT_GNU_IFUNC symbol.
3014 Target_x86_64
<size
>::make_local_ifunc_plt_entry(
3015 Symbol_table
* symtab
, Layout
* layout
,
3016 Sized_relobj_file
<size
, false>* relobj
,
3017 unsigned int local_sym_index
)
3019 if (relobj
->local_has_plt_offset(local_sym_index
))
3021 if (this->plt_
== NULL
)
3022 this->make_plt_section(symtab
, layout
);
3023 unsigned int plt_offset
= this->plt_
->add_local_ifunc_entry(symtab
, layout
,
3026 relobj
->set_local_plt_offset(local_sym_index
, plt_offset
);
3029 // Return the number of entries in the PLT.
3033 Target_x86_64
<size
>::plt_entry_count() const
3035 if (this->plt_
== NULL
)
3037 return this->plt_
->entry_count();
3040 // Return the offset of the first non-reserved PLT entry.
3044 Target_x86_64
<size
>::first_plt_entry_offset() const
3046 if (this->plt_
== NULL
)
3048 return this->plt_
->first_plt_entry_offset();
3051 // Return the size of each PLT entry.
3055 Target_x86_64
<size
>::plt_entry_size() const
3057 if (this->plt_
== NULL
)
3059 return this->plt_
->get_plt_entry_size();
3062 // Create the GOT and PLT sections for an incremental update.
3065 Output_data_got_base
*
3066 Target_x86_64
<size
>::init_got_plt_for_update(Symbol_table
* symtab
,
3068 unsigned int got_count
,
3069 unsigned int plt_count
)
3071 gold_assert(this->got_
== NULL
);
3073 this->got_
= new Output_data_got
<64, false>(got_count
* 8);
3074 layout
->add_output_section_data(".got", elfcpp::SHT_PROGBITS
,
3076 | elfcpp::SHF_WRITE
),
3077 this->got_
, ORDER_RELRO_LAST
,
3080 // Add the three reserved entries.
3081 this->got_plt_
= new Output_data_got_plt_x86_64(layout
, (plt_count
+ 3) * 8);
3082 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
3084 | elfcpp::SHF_WRITE
),
3085 this->got_plt_
, ORDER_NON_RELRO_FIRST
,
3088 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
3089 this->global_offset_table_
=
3090 symtab
->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL
,
3091 Symbol_table::PREDEFINED
,
3093 0, 0, elfcpp::STT_OBJECT
,
3095 elfcpp::STV_HIDDEN
, 0,
3098 // If there are any TLSDESC relocations, they get GOT entries in
3099 // .got.plt after the jump slot entries.
3100 // FIXME: Get the count for TLSDESC entries.
3101 this->got_tlsdesc_
= new Output_data_got
<64, false>(0);
3102 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
3103 elfcpp::SHF_ALLOC
| elfcpp::SHF_WRITE
,
3105 ORDER_NON_RELRO_FIRST
, false);
3107 // If there are any IRELATIVE relocations, they get GOT entries in
3108 // .got.plt after the jump slot and TLSDESC entries.
3109 this->got_irelative_
= new Output_data_space(0, 8, "** GOT IRELATIVE PLT");
3110 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
3111 elfcpp::SHF_ALLOC
| elfcpp::SHF_WRITE
,
3112 this->got_irelative_
,
3113 ORDER_NON_RELRO_FIRST
, false);
3115 // Create the PLT section.
3116 this->plt_
= this->make_data_plt(layout
, this->got_
,
3118 this->got_irelative_
,
3121 // Add unwind information if requested.
3122 if (parameters
->options().ld_generated_unwind_info())
3123 this->plt_
->add_eh_frame(layout
);
3125 layout
->add_output_section_data(".plt", elfcpp::SHT_PROGBITS
,
3126 elfcpp::SHF_ALLOC
| elfcpp::SHF_EXECINSTR
,
3127 this->plt_
, ORDER_PLT
, false);
3129 // Make the sh_info field of .rela.plt point to .plt.
3130 Output_section
* rela_plt_os
= this->plt_
->rela_plt()->output_section();
3131 rela_plt_os
->set_info_section(this->plt_
->output_section());
3133 // Create the rela_dyn section.
3134 this->rela_dyn_section(layout
);
3139 // Reserve a GOT entry for a local symbol, and regenerate any
3140 // necessary dynamic relocations.
3144 Target_x86_64
<size
>::reserve_local_got_entry(
3145 unsigned int got_index
,
3146 Sized_relobj
<size
, false>* obj
,
3148 unsigned int got_type
)
3150 unsigned int got_offset
= got_index
* 8;
3151 Reloc_section
* rela_dyn
= this->rela_dyn_section(NULL
);
3153 this->got_
->reserve_local(got_index
, obj
, r_sym
, got_type
);
3156 case GOT_TYPE_STANDARD
:
3157 if (parameters
->options().output_is_position_independent())
3158 rela_dyn
->add_local_relative(obj
, r_sym
, elfcpp::R_X86_64_RELATIVE
,
3159 this->got_
, got_offset
, 0, false);
3161 case GOT_TYPE_TLS_OFFSET
:
3162 rela_dyn
->add_local(obj
, r_sym
, elfcpp::R_X86_64_TPOFF64
,
3163 this->got_
, got_offset
, 0);
3165 case GOT_TYPE_TLS_PAIR
:
3166 this->got_
->reserve_slot(got_index
+ 1);
3167 rela_dyn
->add_local(obj
, r_sym
, elfcpp::R_X86_64_DTPMOD64
,
3168 this->got_
, got_offset
, 0);
3170 case GOT_TYPE_TLS_DESC
:
3171 gold_fatal(_("TLS_DESC not yet supported for incremental linking"));
3172 // this->got_->reserve_slot(got_index + 1);
3173 // rela_dyn->add_target_specific(elfcpp::R_X86_64_TLSDESC, arg,
3174 // this->got_, got_offset, 0);
3181 // Reserve a GOT entry for a global symbol, and regenerate any
3182 // necessary dynamic relocations.
3186 Target_x86_64
<size
>::reserve_global_got_entry(unsigned int got_index
,
3188 unsigned int got_type
)
3190 unsigned int got_offset
= got_index
* 8;
3191 Reloc_section
* rela_dyn
= this->rela_dyn_section(NULL
);
3193 this->got_
->reserve_global(got_index
, gsym
, got_type
);
3196 case GOT_TYPE_STANDARD
:
3197 if (!gsym
->final_value_is_known())
3199 if (gsym
->is_from_dynobj()
3200 || gsym
->is_undefined()
3201 || gsym
->is_preemptible()
3202 || gsym
->type() == elfcpp::STT_GNU_IFUNC
)
3203 rela_dyn
->add_global(gsym
, elfcpp::R_X86_64_GLOB_DAT
,
3204 this->got_
, got_offset
, 0);
3206 rela_dyn
->add_global_relative(gsym
, elfcpp::R_X86_64_RELATIVE
,
3207 this->got_
, got_offset
, 0, false);
3210 case GOT_TYPE_TLS_OFFSET
:
3211 rela_dyn
->add_global_relative(gsym
, elfcpp::R_X86_64_TPOFF64
,
3212 this->got_
, got_offset
, 0, false);
3214 case GOT_TYPE_TLS_PAIR
:
3215 this->got_
->reserve_slot(got_index
+ 1);
3216 rela_dyn
->add_global_relative(gsym
, elfcpp::R_X86_64_DTPMOD64
,
3217 this->got_
, got_offset
, 0, false);
3218 rela_dyn
->add_global_relative(gsym
, elfcpp::R_X86_64_DTPOFF64
,
3219 this->got_
, got_offset
+ 8, 0, false);
3221 case GOT_TYPE_TLS_DESC
:
3222 this->got_
->reserve_slot(got_index
+ 1);
3223 rela_dyn
->add_global_relative(gsym
, elfcpp::R_X86_64_TLSDESC
,
3224 this->got_
, got_offset
, 0, false);
3231 // Register an existing PLT entry for a global symbol.
3235 Target_x86_64
<size
>::register_global_plt_entry(Symbol_table
* symtab
,
3237 unsigned int plt_index
,
3240 gold_assert(this->plt_
!= NULL
);
3241 gold_assert(!gsym
->has_plt_offset());
3243 this->plt_
->reserve_slot(plt_index
);
3245 gsym
->set_plt_offset((plt_index
+ 1) * this->plt_entry_size());
3247 unsigned int got_offset
= (plt_index
+ 3) * 8;
3248 this->plt_
->add_relocation(symtab
, layout
, gsym
, got_offset
);
3251 // Force a COPY relocation for a given symbol.
3255 Target_x86_64
<size
>::emit_copy_reloc(
3256 Symbol_table
* symtab
, Symbol
* sym
, Output_section
* os
, off_t offset
)
3258 this->copy_relocs_
.emit_copy_reloc(symtab
,
3259 symtab
->get_sized_symbol
<size
>(sym
),
3262 this->rela_dyn_section(NULL
));
3265 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
3269 Target_x86_64
<size
>::define_tls_base_symbol(Symbol_table
* symtab
,
3272 if (this->tls_base_symbol_defined_
)
3275 Output_segment
* tls_segment
= layout
->tls_segment();
3276 if (tls_segment
!= NULL
)
3278 bool is_exec
= parameters
->options().output_is_executable();
3279 symtab
->define_in_output_segment("_TLS_MODULE_BASE_", NULL
,
3280 Symbol_table::PREDEFINED
,
3284 elfcpp::STV_HIDDEN
, 0,
3286 ? Symbol::SEGMENT_END
3287 : Symbol::SEGMENT_START
),
3290 this->tls_base_symbol_defined_
= true;
3293 // Create the reserved PLT and GOT entries for the TLS descriptor resolver.
3297 Target_x86_64
<size
>::reserve_tlsdesc_entries(Symbol_table
* symtab
,
3300 if (this->plt_
== NULL
)
3301 this->make_plt_section(symtab
, layout
);
3303 if (!this->plt_
->has_tlsdesc_entry())
3305 // Allocate the TLSDESC_GOT entry.
3306 Output_data_got
<64, false>* got
= this->got_section(symtab
, layout
);
3307 unsigned int got_offset
= got
->add_constant(0);
3309 // Allocate the TLSDESC_PLT entry.
3310 this->plt_
->reserve_tlsdesc_entry(got_offset
);
3314 // Create a GOT entry for the TLS module index.
3318 Target_x86_64
<size
>::got_mod_index_entry(Symbol_table
* symtab
, Layout
* layout
,
3319 Sized_relobj_file
<size
, false>* object
)
3321 if (this->got_mod_index_offset_
== -1U)
3323 gold_assert(symtab
!= NULL
&& layout
!= NULL
&& object
!= NULL
);
3324 Reloc_section
* rela_dyn
= this->rela_dyn_section(layout
);
3325 Output_data_got
<64, false>* got
= this->got_section(symtab
, layout
);
3326 unsigned int got_offset
= got
->add_constant(0);
3327 rela_dyn
->add_local(object
, 0, elfcpp::R_X86_64_DTPMOD64
, got
,
3329 got
->add_constant(0);
3330 this->got_mod_index_offset_
= got_offset
;
3332 return this->got_mod_index_offset_
;
3335 // Optimize the TLS relocation type based on what we know about the
3336 // symbol. IS_FINAL is true if the final address of this symbol is
3337 // known at link time.
3340 tls::Tls_optimization
3341 Target_x86_64
<size
>::optimize_tls_reloc(bool is_final
, int r_type
)
3343 // If we are generating a shared library, then we can't do anything
3345 if (parameters
->options().shared())
3346 return tls::TLSOPT_NONE
;
3350 case elfcpp::R_X86_64_TLSGD
:
3351 case elfcpp::R_X86_64_GOTPC32_TLSDESC
:
3352 case elfcpp::R_X86_64_TLSDESC_CALL
:
3353 // These are General-Dynamic which permits fully general TLS
3354 // access. Since we know that we are generating an executable,
3355 // we can convert this to Initial-Exec. If we also know that
3356 // this is a local symbol, we can further switch to Local-Exec.
3358 return tls::TLSOPT_TO_LE
;
3359 return tls::TLSOPT_TO_IE
;
3361 case elfcpp::R_X86_64_TLSLD
:
3362 // This is Local-Dynamic, which refers to a local symbol in the
3363 // dynamic TLS block. Since we know that we generating an
3364 // executable, we can switch to Local-Exec.
3365 return tls::TLSOPT_TO_LE
;
3367 case elfcpp::R_X86_64_DTPOFF32
:
3368 case elfcpp::R_X86_64_DTPOFF64
:
3369 // Another Local-Dynamic reloc.
3370 return tls::TLSOPT_TO_LE
;
3372 case elfcpp::R_X86_64_GOTTPOFF
:
3373 // These are Initial-Exec relocs which get the thread offset
3374 // from the GOT. If we know that we are linking against the
3375 // local symbol, we can switch to Local-Exec, which links the
3376 // thread offset into the instruction.
3378 return tls::TLSOPT_TO_LE
;
3379 return tls::TLSOPT_NONE
;
3381 case elfcpp::R_X86_64_TPOFF32
:
3382 // When we already have Local-Exec, there is nothing further we
3384 return tls::TLSOPT_NONE
;
3391 // Get the Reference_flags for a particular relocation.
3395 Target_x86_64
<size
>::Scan::get_reference_flags(unsigned int r_type
)
3399 case elfcpp::R_X86_64_NONE
:
3400 case elfcpp::R_X86_64_GNU_VTINHERIT
:
3401 case elfcpp::R_X86_64_GNU_VTENTRY
:
3402 case elfcpp::R_X86_64_GOTPC32
:
3403 case elfcpp::R_X86_64_GOTPC64
:
3404 // No symbol reference.
3407 case elfcpp::R_X86_64_64
:
3408 case elfcpp::R_X86_64_32
:
3409 case elfcpp::R_X86_64_32S
:
3410 case elfcpp::R_X86_64_16
:
3411 case elfcpp::R_X86_64_8
:
3412 return Symbol::ABSOLUTE_REF
;
3414 case elfcpp::R_X86_64_PC64
:
3415 case elfcpp::R_X86_64_PC32
:
3416 case elfcpp::R_X86_64_PC32_BND
:
3417 case elfcpp::R_X86_64_PC16
:
3418 case elfcpp::R_X86_64_PC8
:
3419 case elfcpp::R_X86_64_GOTOFF64
:
3420 return Symbol::RELATIVE_REF
;
3422 case elfcpp::R_X86_64_PLT32
:
3423 case elfcpp::R_X86_64_PLT32_BND
:
3424 case elfcpp::R_X86_64_PLTOFF64
:
3425 return Symbol::FUNCTION_CALL
| Symbol::RELATIVE_REF
;
3427 case elfcpp::R_X86_64_GOT64
:
3428 case elfcpp::R_X86_64_GOT32
:
3429 case elfcpp::R_X86_64_GOTPCREL64
:
3430 case elfcpp::R_X86_64_GOTPCREL
:
3431 case elfcpp::R_X86_64_GOTPCRELX
:
3432 case elfcpp::R_X86_64_REX_GOTPCRELX
:
3433 case elfcpp::R_X86_64_GOTPLT64
:
3435 return Symbol::ABSOLUTE_REF
;
3437 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
3438 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
3439 case elfcpp::R_X86_64_TLSDESC_CALL
:
3440 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
3441 case elfcpp::R_X86_64_DTPOFF32
:
3442 case elfcpp::R_X86_64_DTPOFF64
:
3443 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
3444 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
3445 return Symbol::TLS_REF
;
3447 case elfcpp::R_X86_64_COPY
:
3448 case elfcpp::R_X86_64_GLOB_DAT
:
3449 case elfcpp::R_X86_64_JUMP_SLOT
:
3450 case elfcpp::R_X86_64_RELATIVE
:
3451 case elfcpp::R_X86_64_IRELATIVE
:
3452 case elfcpp::R_X86_64_TPOFF64
:
3453 case elfcpp::R_X86_64_DTPMOD64
:
3454 case elfcpp::R_X86_64_TLSDESC
:
3455 case elfcpp::R_X86_64_SIZE32
:
3456 case elfcpp::R_X86_64_SIZE64
:
3458 // Not expected. We will give an error later.
3463 // Report an unsupported relocation against a local symbol.
3467 Target_x86_64
<size
>::Scan::unsupported_reloc_local(
3468 Sized_relobj_file
<size
, false>* object
,
3469 unsigned int r_type
)
3471 gold_error(_("%s: unsupported reloc %u against local symbol"),
3472 object
->name().c_str(), r_type
);
3475 // We are about to emit a dynamic relocation of type R_TYPE. If the
3476 // dynamic linker does not support it, issue an error. The GNU linker
3477 // only issues a non-PIC error for an allocated read-only section.
3478 // Here we know the section is allocated, but we don't know that it is
3479 // read-only. But we check for all the relocation types which the
3480 // glibc dynamic linker supports, so it seems appropriate to issue an
3481 // error even if the section is not read-only. If GSYM is not NULL,
3482 // it is the symbol the relocation is against; if it is NULL, the
3483 // relocation is against a local symbol.
3487 Target_x86_64
<size
>::Scan::check_non_pic(Relobj
* object
, unsigned int r_type
,
3492 // These are the relocation types supported by glibc for x86_64
3493 // which should always work.
3494 case elfcpp::R_X86_64_RELATIVE
:
3495 case elfcpp::R_X86_64_IRELATIVE
:
3496 case elfcpp::R_X86_64_GLOB_DAT
:
3497 case elfcpp::R_X86_64_JUMP_SLOT
:
3498 case elfcpp::R_X86_64_DTPMOD64
:
3499 case elfcpp::R_X86_64_DTPOFF64
:
3500 case elfcpp::R_X86_64_TPOFF64
:
3501 case elfcpp::R_X86_64_64
:
3502 case elfcpp::R_X86_64_COPY
:
3505 // glibc supports these reloc types, but they can overflow.
3506 case elfcpp::R_X86_64_PC32
:
3507 case elfcpp::R_X86_64_PC32_BND
:
3508 // A PC relative reference is OK against a local symbol or if
3509 // the symbol is defined locally.
3511 || (!gsym
->is_from_dynobj()
3512 && !gsym
->is_undefined()
3513 && !gsym
->is_preemptible()))
3516 case elfcpp::R_X86_64_32
:
3517 // R_X86_64_32 is OK for x32.
3518 if (size
== 32 && r_type
== elfcpp::R_X86_64_32
)
3520 if (this->issued_non_pic_error_
)
3522 gold_assert(parameters
->options().output_is_position_independent());
3524 object
->error(_("requires dynamic R_X86_64_32 reloc which may "
3525 "overflow at runtime; recompile with -fPIC"));
3531 case elfcpp::R_X86_64_32
:
3532 r_name
= "R_X86_64_32";
3534 case elfcpp::R_X86_64_PC32
:
3535 r_name
= "R_X86_64_PC32";
3537 case elfcpp::R_X86_64_PC32_BND
:
3538 r_name
= "R_X86_64_PC32_BND";
3544 object
->error(_("requires dynamic %s reloc against '%s' "
3545 "which may overflow at runtime; recompile "
3547 r_name
, gsym
->name());
3549 this->issued_non_pic_error_
= true;
3553 // This prevents us from issuing more than one error per reloc
3554 // section. But we can still wind up issuing more than one
3555 // error per object file.
3556 if (this->issued_non_pic_error_
)
3558 gold_assert(parameters
->options().output_is_position_independent());
3559 object
->error(_("requires unsupported dynamic reloc %u; "
3560 "recompile with -fPIC"),
3562 this->issued_non_pic_error_
= true;
3565 case elfcpp::R_X86_64_NONE
:
3570 // Return whether we need to make a PLT entry for a relocation of the
3571 // given type against a STT_GNU_IFUNC symbol.
3575 Target_x86_64
<size
>::Scan::reloc_needs_plt_for_ifunc(
3576 Sized_relobj_file
<size
, false>* object
,
3577 unsigned int r_type
)
3579 int flags
= Scan::get_reference_flags(r_type
);
3580 if (flags
& Symbol::TLS_REF
)
3581 gold_error(_("%s: unsupported TLS reloc %u for IFUNC symbol"),
3582 object
->name().c_str(), r_type
);
3586 // Scan a relocation for a local symbol.
3590 Target_x86_64
<size
>::Scan::local(Symbol_table
* symtab
,
3592 Target_x86_64
<size
>* target
,
3593 Sized_relobj_file
<size
, false>* object
,
3594 unsigned int data_shndx
,
3595 Output_section
* output_section
,
3596 const elfcpp::Rela
<size
, false>& reloc
,
3597 unsigned int r_type
,
3598 const elfcpp::Sym
<size
, false>& lsym
,
3604 // A local STT_GNU_IFUNC symbol may require a PLT entry.
3605 bool is_ifunc
= lsym
.get_st_type() == elfcpp::STT_GNU_IFUNC
;
3606 if (is_ifunc
&& this->reloc_needs_plt_for_ifunc(object
, r_type
))
3608 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(reloc
.get_r_info());
3609 target
->make_local_ifunc_plt_entry(symtab
, layout
, object
, r_sym
);
3614 case elfcpp::R_X86_64_NONE
:
3615 case elfcpp::R_X86_64_GNU_VTINHERIT
:
3616 case elfcpp::R_X86_64_GNU_VTENTRY
:
3619 case elfcpp::R_X86_64_64
:
3620 // If building a shared library (or a position-independent
3621 // executable), we need to create a dynamic relocation for this
3622 // location. The relocation applied at link time will apply the
3623 // link-time value, so we flag the location with an
3624 // R_X86_64_RELATIVE relocation so the dynamic loader can
3625 // relocate it easily.
3626 if (parameters
->options().output_is_position_independent())
3628 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(reloc
.get_r_info());
3629 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
3630 rela_dyn
->add_local_relative(object
, r_sym
,
3632 ? elfcpp::R_X86_64_RELATIVE64
3633 : elfcpp::R_X86_64_RELATIVE
),
3634 output_section
, data_shndx
,
3635 reloc
.get_r_offset(),
3636 reloc
.get_r_addend(), is_ifunc
);
3640 case elfcpp::R_X86_64_32
:
3641 case elfcpp::R_X86_64_32S
:
3642 case elfcpp::R_X86_64_16
:
3643 case elfcpp::R_X86_64_8
:
3644 // If building a shared library (or a position-independent
3645 // executable), we need to create a dynamic relocation for this
3646 // location. We can't use an R_X86_64_RELATIVE relocation
3647 // because that is always a 64-bit relocation.
3648 if (parameters
->options().output_is_position_independent())
3650 // Use R_X86_64_RELATIVE relocation for R_X86_64_32 under x32.
3651 if (size
== 32 && r_type
== elfcpp::R_X86_64_32
)
3653 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(reloc
.get_r_info());
3654 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
3655 rela_dyn
->add_local_relative(object
, r_sym
,
3656 elfcpp::R_X86_64_RELATIVE
,
3657 output_section
, data_shndx
,
3658 reloc
.get_r_offset(),
3659 reloc
.get_r_addend(), is_ifunc
);
3663 this->check_non_pic(object
, r_type
, NULL
);
3665 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
3666 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(reloc
.get_r_info());
3667 if (lsym
.get_st_type() != elfcpp::STT_SECTION
)
3668 rela_dyn
->add_local(object
, r_sym
, r_type
, output_section
,
3669 data_shndx
, reloc
.get_r_offset(),
3670 reloc
.get_r_addend());
3673 gold_assert(lsym
.get_st_value() == 0);
3674 unsigned int shndx
= lsym
.get_st_shndx();
3676 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
,
3679 object
->error(_("section symbol %u has bad shndx %u"),
3682 rela_dyn
->add_local_section(object
, shndx
,
3683 r_type
, output_section
,
3684 data_shndx
, reloc
.get_r_offset(),
3685 reloc
.get_r_addend());
3690 case elfcpp::R_X86_64_PC64
:
3691 case elfcpp::R_X86_64_PC32
:
3692 case elfcpp::R_X86_64_PC32_BND
:
3693 case elfcpp::R_X86_64_PC16
:
3694 case elfcpp::R_X86_64_PC8
:
3697 case elfcpp::R_X86_64_PLT32
:
3698 case elfcpp::R_X86_64_PLT32_BND
:
3699 // Since we know this is a local symbol, we can handle this as a
3703 case elfcpp::R_X86_64_GOTPC32
:
3704 case elfcpp::R_X86_64_GOTOFF64
:
3705 case elfcpp::R_X86_64_GOTPC64
:
3706 case elfcpp::R_X86_64_PLTOFF64
:
3707 // We need a GOT section.
3708 target
->got_section(symtab
, layout
);
3709 // For PLTOFF64, we'd normally want a PLT section, but since we
3710 // know this is a local symbol, no PLT is needed.
3713 case elfcpp::R_X86_64_GOT64
:
3714 case elfcpp::R_X86_64_GOT32
:
3715 case elfcpp::R_X86_64_GOTPCREL64
:
3716 case elfcpp::R_X86_64_GOTPCREL
:
3717 case elfcpp::R_X86_64_GOTPCRELX
:
3718 case elfcpp::R_X86_64_REX_GOTPCRELX
:
3719 case elfcpp::R_X86_64_GOTPLT64
:
3721 // The symbol requires a GOT section.
3722 Output_data_got
<64, false>* got
= target
->got_section(symtab
, layout
);
3724 // If the relocation symbol isn't IFUNC,
3725 // and is local, then we will convert
3726 // mov foo@GOTPCREL(%rip), %reg
3727 // to lea foo(%rip), %reg.
3728 // in Relocate::relocate.
3729 if (!parameters
->incremental()
3730 && (r_type
== elfcpp::R_X86_64_GOTPCREL
3731 || r_type
== elfcpp::R_X86_64_GOTPCRELX
3732 || r_type
== elfcpp::R_X86_64_REX_GOTPCRELX
)
3733 && reloc
.get_r_addend() == -4
3734 && reloc
.get_r_offset() >= 2
3737 section_size_type stype
;
3738 const unsigned char* view
= object
->section_contents(data_shndx
,
3740 if (view
[reloc
.get_r_offset() - 2] == 0x8b)
3744 // The symbol requires a GOT entry.
3745 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(reloc
.get_r_info());
3747 // For a STT_GNU_IFUNC symbol we want the PLT offset. That
3748 // lets function pointers compare correctly with shared
3749 // libraries. Otherwise we would need an IRELATIVE reloc.
3752 is_new
= got
->add_local_plt(object
, r_sym
, GOT_TYPE_STANDARD
);
3754 is_new
= got
->add_local(object
, r_sym
, GOT_TYPE_STANDARD
);
3757 // If we are generating a shared object, we need to add a
3758 // dynamic relocation for this symbol's GOT entry.
3759 if (parameters
->options().output_is_position_independent())
3761 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
3762 // R_X86_64_RELATIVE assumes a 64-bit relocation.
3763 if (r_type
!= elfcpp::R_X86_64_GOT32
)
3765 unsigned int got_offset
=
3766 object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
);
3767 rela_dyn
->add_local_relative(object
, r_sym
,
3768 elfcpp::R_X86_64_RELATIVE
,
3769 got
, got_offset
, 0, is_ifunc
);
3773 this->check_non_pic(object
, r_type
, NULL
);
3775 gold_assert(lsym
.get_st_type() != elfcpp::STT_SECTION
);
3776 rela_dyn
->add_local(
3777 object
, r_sym
, r_type
, got
,
3778 object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
), 0);
3782 // For GOTPLT64, we'd normally want a PLT section, but since
3783 // we know this is a local symbol, no PLT is needed.
3787 case elfcpp::R_X86_64_COPY
:
3788 case elfcpp::R_X86_64_GLOB_DAT
:
3789 case elfcpp::R_X86_64_JUMP_SLOT
:
3790 case elfcpp::R_X86_64_RELATIVE
:
3791 case elfcpp::R_X86_64_IRELATIVE
:
3792 // These are outstanding tls relocs, which are unexpected when linking
3793 case elfcpp::R_X86_64_TPOFF64
:
3794 case elfcpp::R_X86_64_DTPMOD64
:
3795 case elfcpp::R_X86_64_TLSDESC
:
3796 gold_error(_("%s: unexpected reloc %u in object file"),
3797 object
->name().c_str(), r_type
);
3800 // These are initial tls relocs, which are expected when linking
3801 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
3802 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
3803 case elfcpp::R_X86_64_TLSDESC_CALL
:
3804 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
3805 case elfcpp::R_X86_64_DTPOFF32
:
3806 case elfcpp::R_X86_64_DTPOFF64
:
3807 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
3808 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
3810 bool output_is_shared
= parameters
->options().shared();
3811 const tls::Tls_optimization optimized_type
3812 = Target_x86_64
<size
>::optimize_tls_reloc(!output_is_shared
,
3816 case elfcpp::R_X86_64_TLSGD
: // General-dynamic
3817 if (optimized_type
== tls::TLSOPT_NONE
)
3819 // Create a pair of GOT entries for the module index and
3820 // dtv-relative offset.
3821 Output_data_got
<64, false>* got
3822 = target
->got_section(symtab
, layout
);
3823 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(reloc
.get_r_info());
3824 unsigned int shndx
= lsym
.get_st_shndx();
3826 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
, &is_ordinary
);
3828 object
->error(_("local symbol %u has bad shndx %u"),
3831 got
->add_local_pair_with_rel(object
, r_sym
,
3834 target
->rela_dyn_section(layout
),
3835 elfcpp::R_X86_64_DTPMOD64
);
3837 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
3838 unsupported_reloc_local(object
, r_type
);
3841 case elfcpp::R_X86_64_GOTPC32_TLSDESC
:
3842 target
->define_tls_base_symbol(symtab
, layout
);
3843 if (optimized_type
== tls::TLSOPT_NONE
)
3845 // Create reserved PLT and GOT entries for the resolver.
3846 target
->reserve_tlsdesc_entries(symtab
, layout
);
3848 // Generate a double GOT entry with an
3849 // R_X86_64_TLSDESC reloc. The R_X86_64_TLSDESC reloc
3850 // is resolved lazily, so the GOT entry needs to be in
3851 // an area in .got.plt, not .got. Call got_section to
3852 // make sure the section has been created.
3853 target
->got_section(symtab
, layout
);
3854 Output_data_got
<64, false>* got
= target
->got_tlsdesc_section();
3855 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(reloc
.get_r_info());
3856 if (!object
->local_has_got_offset(r_sym
, GOT_TYPE_TLS_DESC
))
3858 unsigned int got_offset
= got
->add_constant(0);
3859 got
->add_constant(0);
3860 object
->set_local_got_offset(r_sym
, GOT_TYPE_TLS_DESC
,
3862 Reloc_section
* rt
= target
->rela_tlsdesc_section(layout
);
3863 // We store the arguments we need in a vector, and
3864 // use the index into the vector as the parameter
3865 // to pass to the target specific routines.
3866 uintptr_t intarg
= target
->add_tlsdesc_info(object
, r_sym
);
3867 void* arg
= reinterpret_cast<void*>(intarg
);
3868 rt
->add_target_specific(elfcpp::R_X86_64_TLSDESC
, arg
,
3869 got
, got_offset
, 0);
3872 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
3873 unsupported_reloc_local(object
, r_type
);
3876 case elfcpp::R_X86_64_TLSDESC_CALL
:
3879 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
3880 if (optimized_type
== tls::TLSOPT_NONE
)
3882 // Create a GOT entry for the module index.
3883 target
->got_mod_index_entry(symtab
, layout
, object
);
3885 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
3886 unsupported_reloc_local(object
, r_type
);
3889 case elfcpp::R_X86_64_DTPOFF32
:
3890 case elfcpp::R_X86_64_DTPOFF64
:
3893 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
3894 layout
->set_has_static_tls();
3895 if (optimized_type
== tls::TLSOPT_NONE
)
3897 // Create a GOT entry for the tp-relative offset.
3898 Output_data_got
<64, false>* got
3899 = target
->got_section(symtab
, layout
);
3900 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(reloc
.get_r_info());
3901 got
->add_local_with_rel(object
, r_sym
, GOT_TYPE_TLS_OFFSET
,
3902 target
->rela_dyn_section(layout
),
3903 elfcpp::R_X86_64_TPOFF64
);
3905 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
3906 unsupported_reloc_local(object
, r_type
);
3909 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
3910 layout
->set_has_static_tls();
3911 if (output_is_shared
)
3912 unsupported_reloc_local(object
, r_type
);
3921 case elfcpp::R_X86_64_SIZE32
:
3922 case elfcpp::R_X86_64_SIZE64
:
3924 gold_error(_("%s: unsupported reloc %u against local symbol"),
3925 object
->name().c_str(), r_type
);
3931 // Report an unsupported relocation against a global symbol.
3935 Target_x86_64
<size
>::Scan::unsupported_reloc_global(
3936 Sized_relobj_file
<size
, false>* object
,
3937 unsigned int r_type
,
3940 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
3941 object
->name().c_str(), r_type
, gsym
->demangled_name().c_str());
3944 // Returns true if this relocation type could be that of a function pointer.
3947 Target_x86_64
<size
>::Scan::possible_function_pointer_reloc(
3948 Sized_relobj_file
<size
, false>* src_obj
,
3949 unsigned int src_indx
,
3950 unsigned int r_offset
,
3951 unsigned int r_type
)
3955 case elfcpp::R_X86_64_64
:
3956 case elfcpp::R_X86_64_32
:
3957 case elfcpp::R_X86_64_32S
:
3958 case elfcpp::R_X86_64_16
:
3959 case elfcpp::R_X86_64_8
:
3960 case elfcpp::R_X86_64_GOT64
:
3961 case elfcpp::R_X86_64_GOT32
:
3962 case elfcpp::R_X86_64_GOTPCREL64
:
3963 case elfcpp::R_X86_64_GOTPCREL
:
3964 case elfcpp::R_X86_64_GOTPCRELX
:
3965 case elfcpp::R_X86_64_REX_GOTPCRELX
:
3966 case elfcpp::R_X86_64_GOTPLT64
:
3970 case elfcpp::R_X86_64_PC32
:
3972 // This relocation may be used both for function calls and
3973 // for taking address of a function. We distinguish between
3974 // them by checking the opcodes.
3975 uint64_t sh_flags
= src_obj
->section_flags(src_indx
);
3976 bool is_executable
= (sh_flags
& elfcpp::SHF_EXECINSTR
) != 0;
3979 section_size_type stype
;
3980 const unsigned char* view
= src_obj
->section_contents(src_indx
,
3986 && view
[r_offset
- 1] == 0xe8)
3991 && view
[r_offset
- 1] == 0xe9)
3994 // jo/jno/jb/jnb/je/jne/jna/ja/js/jns/jp/jnp/jl/jge/jle/jg
3996 && view
[r_offset
- 2] == 0x0f
3997 && view
[r_offset
- 1] >= 0x80
3998 && view
[r_offset
- 1] <= 0x8f)
4002 // Be conservative and treat all others as function pointers.
4009 // For safe ICF, scan a relocation for a local symbol to check if it
4010 // corresponds to a function pointer being taken. In that case mark
4011 // the function whose pointer was taken as not foldable.
4015 Target_x86_64
<size
>::Scan::local_reloc_may_be_function_pointer(
4018 Target_x86_64
<size
>* ,
4019 Sized_relobj_file
<size
, false>* src_obj
,
4020 unsigned int src_indx
,
4022 const elfcpp::Rela
<size
, false>& reloc
,
4023 unsigned int r_type
,
4024 const elfcpp::Sym
<size
, false>&)
4026 return possible_function_pointer_reloc(src_obj
, src_indx
,
4027 reloc
.get_r_offset(), r_type
);
4030 // For safe ICF, scan a relocation for a global symbol to check if it
4031 // corresponds to a function pointer being taken. In that case mark
4032 // the function whose pointer was taken as not foldable.
4036 Target_x86_64
<size
>::Scan::global_reloc_may_be_function_pointer(
4039 Target_x86_64
<size
>* ,
4040 Sized_relobj_file
<size
, false>* src_obj
,
4041 unsigned int src_indx
,
4043 const elfcpp::Rela
<size
, false>& reloc
,
4044 unsigned int r_type
,
4047 return possible_function_pointer_reloc(src_obj
, src_indx
,
4048 reloc
.get_r_offset(), r_type
);
4051 // Scan a relocation for a global symbol.
4055 Target_x86_64
<size
>::Scan::global(Symbol_table
* symtab
,
4057 Target_x86_64
<size
>* target
,
4058 Sized_relobj_file
<size
, false>* object
,
4059 unsigned int data_shndx
,
4060 Output_section
* output_section
,
4061 const elfcpp::Rela
<size
, false>& reloc
,
4062 unsigned int r_type
,
4065 // A STT_GNU_IFUNC symbol may require a PLT entry.
4066 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
4067 && this->reloc_needs_plt_for_ifunc(object
, r_type
))
4068 target
->make_plt_entry(symtab
, layout
, gsym
);
4072 case elfcpp::R_X86_64_NONE
:
4073 case elfcpp::R_X86_64_GNU_VTINHERIT
:
4074 case elfcpp::R_X86_64_GNU_VTENTRY
:
4077 case elfcpp::R_X86_64_64
:
4078 case elfcpp::R_X86_64_32
:
4079 case elfcpp::R_X86_64_32S
:
4080 case elfcpp::R_X86_64_16
:
4081 case elfcpp::R_X86_64_8
:
4083 // Make a PLT entry if necessary.
4084 if (gsym
->needs_plt_entry())
4086 target
->make_plt_entry(symtab
, layout
, gsym
);
4087 // Since this is not a PC-relative relocation, we may be
4088 // taking the address of a function. In that case we need to
4089 // set the entry in the dynamic symbol table to the address of
4091 if (gsym
->is_from_dynobj() && !parameters
->options().shared())
4092 gsym
->set_needs_dynsym_value();
4094 // Make a dynamic relocation if necessary.
4095 if (gsym
->needs_dynamic_reloc(Scan::get_reference_flags(r_type
)))
4097 if (!parameters
->options().output_is_position_independent()
4098 && gsym
->may_need_copy_reloc())
4100 target
->copy_reloc(symtab
, layout
, object
,
4101 data_shndx
, output_section
, gsym
, reloc
);
4103 else if (((size
== 64 && r_type
== elfcpp::R_X86_64_64
)
4104 || (size
== 32 && r_type
== elfcpp::R_X86_64_32
))
4105 && gsym
->type() == elfcpp::STT_GNU_IFUNC
4106 && gsym
->can_use_relative_reloc(false)
4107 && !gsym
->is_from_dynobj()
4108 && !gsym
->is_undefined()
4109 && !gsym
->is_preemptible())
4111 // Use an IRELATIVE reloc for a locally defined
4112 // STT_GNU_IFUNC symbol. This makes a function
4113 // address in a PIE executable match the address in a
4114 // shared library that it links against.
4115 Reloc_section
* rela_dyn
=
4116 target
->rela_irelative_section(layout
);
4117 unsigned int r_type
= elfcpp::R_X86_64_IRELATIVE
;
4118 rela_dyn
->add_symbolless_global_addend(gsym
, r_type
,
4119 output_section
, object
,
4121 reloc
.get_r_offset(),
4122 reloc
.get_r_addend());
4124 else if (((size
== 64 && r_type
== elfcpp::R_X86_64_64
)
4125 || (size
== 32 && r_type
== elfcpp::R_X86_64_32
))
4126 && gsym
->can_use_relative_reloc(false))
4128 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
4129 rela_dyn
->add_global_relative(gsym
, elfcpp::R_X86_64_RELATIVE
,
4130 output_section
, object
,
4132 reloc
.get_r_offset(),
4133 reloc
.get_r_addend(), false);
4137 this->check_non_pic(object
, r_type
, gsym
);
4138 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
4139 rela_dyn
->add_global(gsym
, r_type
, output_section
, object
,
4140 data_shndx
, reloc
.get_r_offset(),
4141 reloc
.get_r_addend());
4147 case elfcpp::R_X86_64_PC64
:
4148 case elfcpp::R_X86_64_PC32
:
4149 case elfcpp::R_X86_64_PC32_BND
:
4150 case elfcpp::R_X86_64_PC16
:
4151 case elfcpp::R_X86_64_PC8
:
4153 // Make a PLT entry if necessary.
4154 if (gsym
->needs_plt_entry())
4155 target
->make_plt_entry(symtab
, layout
, gsym
);
4156 // Make a dynamic relocation if necessary.
4157 if (gsym
->needs_dynamic_reloc(Scan::get_reference_flags(r_type
)))
4159 if (parameters
->options().output_is_executable()
4160 && gsym
->may_need_copy_reloc())
4162 target
->copy_reloc(symtab
, layout
, object
,
4163 data_shndx
, output_section
, gsym
, reloc
);
4167 this->check_non_pic(object
, r_type
, gsym
);
4168 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
4169 rela_dyn
->add_global(gsym
, r_type
, output_section
, object
,
4170 data_shndx
, reloc
.get_r_offset(),
4171 reloc
.get_r_addend());
4177 case elfcpp::R_X86_64_GOT64
:
4178 case elfcpp::R_X86_64_GOT32
:
4179 case elfcpp::R_X86_64_GOTPCREL64
:
4180 case elfcpp::R_X86_64_GOTPCREL
:
4181 case elfcpp::R_X86_64_GOTPCRELX
:
4182 case elfcpp::R_X86_64_REX_GOTPCRELX
:
4183 case elfcpp::R_X86_64_GOTPLT64
:
4185 // The symbol requires a GOT entry.
4186 Output_data_got
<64, false>* got
= target
->got_section(symtab
, layout
);
4188 // If we convert this from
4189 // mov foo@GOTPCREL(%rip), %reg
4190 // to lea foo(%rip), %reg.
4193 // (callq|jmpq) *foo@GOTPCRELX(%rip) to
4195 // in Relocate::relocate, then there is nothing to do here.
4196 // We cannot make these optimizations in incremental linking mode,
4197 // because we look at the opcode to decide whether or not to make
4198 // change, and during an incremental update, the change may have
4199 // already been applied.
4201 Lazy_view
<size
> view(object
, data_shndx
);
4202 size_t r_offset
= reloc
.get_r_offset();
4203 if (!parameters
->incremental()
4204 && reloc
.get_r_addend() == -4
4206 && Target_x86_64
<size
>::can_convert_mov_to_lea(gsym
, r_type
,
4210 if (!parameters
->incremental()
4212 && Target_x86_64
<size
>::can_convert_callq_to_direct(gsym
, r_type
,
4217 if (gsym
->final_value_is_known())
4219 // For a STT_GNU_IFUNC symbol we want the PLT address.
4220 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
)
4221 got
->add_global_plt(gsym
, GOT_TYPE_STANDARD
);
4223 got
->add_global(gsym
, GOT_TYPE_STANDARD
);
4227 // If this symbol is not fully resolved, we need to add a
4228 // dynamic relocation for it.
4229 Reloc_section
* rela_dyn
= target
->rela_dyn_section(layout
);
4231 // Use a GLOB_DAT rather than a RELATIVE reloc if:
4233 // 1) The symbol may be defined in some other module.
4235 // 2) We are building a shared library and this is a
4236 // protected symbol; using GLOB_DAT means that the dynamic
4237 // linker can use the address of the PLT in the main
4238 // executable when appropriate so that function address
4239 // comparisons work.
4241 // 3) This is a STT_GNU_IFUNC symbol in position dependent
4242 // code, again so that function address comparisons work.
4243 if (gsym
->is_from_dynobj()
4244 || gsym
->is_undefined()
4245 || gsym
->is_preemptible()
4246 || (gsym
->visibility() == elfcpp::STV_PROTECTED
4247 && parameters
->options().shared())
4248 || (gsym
->type() == elfcpp::STT_GNU_IFUNC
4249 && parameters
->options().output_is_position_independent()))
4250 got
->add_global_with_rel(gsym
, GOT_TYPE_STANDARD
, rela_dyn
,
4251 elfcpp::R_X86_64_GLOB_DAT
);
4254 // For a STT_GNU_IFUNC symbol we want to write the PLT
4255 // offset into the GOT, so that function pointer
4256 // comparisons work correctly.
4258 if (gsym
->type() != elfcpp::STT_GNU_IFUNC
)
4259 is_new
= got
->add_global(gsym
, GOT_TYPE_STANDARD
);
4262 is_new
= got
->add_global_plt(gsym
, GOT_TYPE_STANDARD
);
4263 // Tell the dynamic linker to use the PLT address
4264 // when resolving relocations.
4265 if (gsym
->is_from_dynobj()
4266 && !parameters
->options().shared())
4267 gsym
->set_needs_dynsym_value();
4271 unsigned int got_off
= gsym
->got_offset(GOT_TYPE_STANDARD
);
4272 rela_dyn
->add_global_relative(gsym
,
4273 elfcpp::R_X86_64_RELATIVE
,
4274 got
, got_off
, 0, false);
4281 case elfcpp::R_X86_64_PLT32
:
4282 case elfcpp::R_X86_64_PLT32_BND
:
4283 // If the symbol is fully resolved, this is just a PC32 reloc.
4284 // Otherwise we need a PLT entry.
4285 if (gsym
->final_value_is_known())
4287 // If building a shared library, we can also skip the PLT entry
4288 // if the symbol is defined in the output file and is protected
4290 if (gsym
->is_defined()
4291 && !gsym
->is_from_dynobj()
4292 && !gsym
->is_preemptible())
4294 target
->make_plt_entry(symtab
, layout
, gsym
);
4297 case elfcpp::R_X86_64_GOTPC32
:
4298 case elfcpp::R_X86_64_GOTOFF64
:
4299 case elfcpp::R_X86_64_GOTPC64
:
4300 case elfcpp::R_X86_64_PLTOFF64
:
4301 // We need a GOT section.
4302 target
->got_section(symtab
, layout
);
4303 // For PLTOFF64, we also need a PLT entry (but only if the
4304 // symbol is not fully resolved).
4305 if (r_type
== elfcpp::R_X86_64_PLTOFF64
4306 && !gsym
->final_value_is_known())
4307 target
->make_plt_entry(symtab
, layout
, gsym
);
4310 case elfcpp::R_X86_64_COPY
:
4311 case elfcpp::R_X86_64_GLOB_DAT
:
4312 case elfcpp::R_X86_64_JUMP_SLOT
:
4313 case elfcpp::R_X86_64_RELATIVE
:
4314 case elfcpp::R_X86_64_IRELATIVE
:
4315 // These are outstanding tls relocs, which are unexpected when linking
4316 case elfcpp::R_X86_64_TPOFF64
:
4317 case elfcpp::R_X86_64_DTPMOD64
:
4318 case elfcpp::R_X86_64_TLSDESC
:
4319 gold_error(_("%s: unexpected reloc %u in object file"),
4320 object
->name().c_str(), r_type
);
4323 // These are initial tls relocs, which are expected for global()
4324 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
4325 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
4326 case elfcpp::R_X86_64_TLSDESC_CALL
:
4327 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
4328 case elfcpp::R_X86_64_DTPOFF32
:
4329 case elfcpp::R_X86_64_DTPOFF64
:
4330 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
4331 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
4333 // For the Initial-Exec model, we can treat undef symbols as final
4334 // when building an executable.
4335 const bool is_final
= (gsym
->final_value_is_known() ||
4336 (r_type
== elfcpp::R_X86_64_GOTTPOFF
&&
4337 gsym
->is_undefined() &&
4338 parameters
->options().output_is_executable()));
4339 const tls::Tls_optimization optimized_type
4340 = Target_x86_64
<size
>::optimize_tls_reloc(is_final
, r_type
);
4343 case elfcpp::R_X86_64_TLSGD
: // General-dynamic
4344 if (optimized_type
== tls::TLSOPT_NONE
)
4346 // Create a pair of GOT entries for the module index and
4347 // dtv-relative offset.
4348 Output_data_got
<64, false>* got
4349 = target
->got_section(symtab
, layout
);
4350 got
->add_global_pair_with_rel(gsym
, GOT_TYPE_TLS_PAIR
,
4351 target
->rela_dyn_section(layout
),
4352 elfcpp::R_X86_64_DTPMOD64
,
4353 elfcpp::R_X86_64_DTPOFF64
);
4355 else if (optimized_type
== tls::TLSOPT_TO_IE
)
4357 // Create a GOT entry for the tp-relative offset.
4358 Output_data_got
<64, false>* got
4359 = target
->got_section(symtab
, layout
);
4360 got
->add_global_with_rel(gsym
, GOT_TYPE_TLS_OFFSET
,
4361 target
->rela_dyn_section(layout
),
4362 elfcpp::R_X86_64_TPOFF64
);
4364 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
4365 unsupported_reloc_global(object
, r_type
, gsym
);
4368 case elfcpp::R_X86_64_GOTPC32_TLSDESC
:
4369 target
->define_tls_base_symbol(symtab
, layout
);
4370 if (optimized_type
== tls::TLSOPT_NONE
)
4372 // Create reserved PLT and GOT entries for the resolver.
4373 target
->reserve_tlsdesc_entries(symtab
, layout
);
4375 // Create a double GOT entry with an R_X86_64_TLSDESC
4376 // reloc. The R_X86_64_TLSDESC reloc is resolved
4377 // lazily, so the GOT entry needs to be in an area in
4378 // .got.plt, not .got. Call got_section to make sure
4379 // the section has been created.
4380 target
->got_section(symtab
, layout
);
4381 Output_data_got
<64, false>* got
= target
->got_tlsdesc_section();
4382 Reloc_section
* rt
= target
->rela_tlsdesc_section(layout
);
4383 got
->add_global_pair_with_rel(gsym
, GOT_TYPE_TLS_DESC
, rt
,
4384 elfcpp::R_X86_64_TLSDESC
, 0);
4386 else if (optimized_type
== tls::TLSOPT_TO_IE
)
4388 // Create a GOT entry for the tp-relative offset.
4389 Output_data_got
<64, false>* got
4390 = target
->got_section(symtab
, layout
);
4391 got
->add_global_with_rel(gsym
, GOT_TYPE_TLS_OFFSET
,
4392 target
->rela_dyn_section(layout
),
4393 elfcpp::R_X86_64_TPOFF64
);
4395 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
4396 unsupported_reloc_global(object
, r_type
, gsym
);
4399 case elfcpp::R_X86_64_TLSDESC_CALL
:
4402 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
4403 if (optimized_type
== tls::TLSOPT_NONE
)
4405 // Create a GOT entry for the module index.
4406 target
->got_mod_index_entry(symtab
, layout
, object
);
4408 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
4409 unsupported_reloc_global(object
, r_type
, gsym
);
4412 case elfcpp::R_X86_64_DTPOFF32
:
4413 case elfcpp::R_X86_64_DTPOFF64
:
4416 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
4417 layout
->set_has_static_tls();
4418 if (optimized_type
== tls::TLSOPT_NONE
)
4420 // Create a GOT entry for the tp-relative offset.
4421 Output_data_got
<64, false>* got
4422 = target
->got_section(symtab
, layout
);
4423 got
->add_global_with_rel(gsym
, GOT_TYPE_TLS_OFFSET
,
4424 target
->rela_dyn_section(layout
),
4425 elfcpp::R_X86_64_TPOFF64
);
4427 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
4428 unsupported_reloc_global(object
, r_type
, gsym
);
4431 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
4432 layout
->set_has_static_tls();
4433 if (parameters
->options().shared())
4434 unsupported_reloc_global(object
, r_type
, gsym
);
4443 case elfcpp::R_X86_64_SIZE32
:
4444 case elfcpp::R_X86_64_SIZE64
:
4446 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
4447 object
->name().c_str(), r_type
,
4448 gsym
->demangled_name().c_str());
4455 Target_x86_64
<size
>::gc_process_relocs(Symbol_table
* symtab
,
4457 Sized_relobj_file
<size
, false>* object
,
4458 unsigned int data_shndx
,
4459 unsigned int sh_type
,
4460 const unsigned char* prelocs
,
4462 Output_section
* output_section
,
4463 bool needs_special_offset_handling
,
4464 size_t local_symbol_count
,
4465 const unsigned char* plocal_symbols
)
4467 typedef gold::Default_classify_reloc
<elfcpp::SHT_RELA
, size
, false>
4470 if (sh_type
== elfcpp::SHT_REL
)
4475 gold::gc_process_relocs
<size
, false, Target_x86_64
<size
>, Scan
,
4485 needs_special_offset_handling
,
4490 // Scan relocations for a section.
4494 Target_x86_64
<size
>::scan_relocs(Symbol_table
* symtab
,
4496 Sized_relobj_file
<size
, false>* object
,
4497 unsigned int data_shndx
,
4498 unsigned int sh_type
,
4499 const unsigned char* prelocs
,
4501 Output_section
* output_section
,
4502 bool needs_special_offset_handling
,
4503 size_t local_symbol_count
,
4504 const unsigned char* plocal_symbols
)
4506 typedef gold::Default_classify_reloc
<elfcpp::SHT_RELA
, size
, false>
4509 if (sh_type
== elfcpp::SHT_REL
)
4511 gold_error(_("%s: unsupported REL reloc section"),
4512 object
->name().c_str());
4516 gold::scan_relocs
<size
, false, Target_x86_64
<size
>, Scan
, Classify_reloc
>(
4525 needs_special_offset_handling
,
4530 // Finalize the sections.
4534 Target_x86_64
<size
>::do_finalize_sections(
4536 const Input_objects
*,
4537 Symbol_table
* symtab
)
4539 const Reloc_section
* rel_plt
= (this->plt_
== NULL
4541 : this->plt_
->rela_plt());
4542 layout
->add_target_dynamic_tags(false, this->got_plt_
, rel_plt
,
4543 this->rela_dyn_
, true, false);
4545 // Fill in some more dynamic tags.
4546 Output_data_dynamic
* const odyn
= layout
->dynamic_data();
4549 if (this->plt_
!= NULL
4550 && this->plt_
->output_section() != NULL
4551 && this->plt_
->has_tlsdesc_entry())
4553 unsigned int plt_offset
= this->plt_
->get_tlsdesc_plt_offset();
4554 unsigned int got_offset
= this->plt_
->get_tlsdesc_got_offset();
4555 this->got_
->finalize_data_size();
4556 odyn
->add_section_plus_offset(elfcpp::DT_TLSDESC_PLT
,
4557 this->plt_
, plt_offset
);
4558 odyn
->add_section_plus_offset(elfcpp::DT_TLSDESC_GOT
,
4559 this->got_
, got_offset
);
4563 // Emit any relocs we saved in an attempt to avoid generating COPY
4565 if (this->copy_relocs_
.any_saved_relocs())
4566 this->copy_relocs_
.emit(this->rela_dyn_section(layout
));
4568 // Set the size of the _GLOBAL_OFFSET_TABLE_ symbol to the size of
4569 // the .got.plt section.
4570 Symbol
* sym
= this->global_offset_table_
;
4573 uint64_t data_size
= this->got_plt_
->current_data_size();
4574 symtab
->get_sized_symbol
<size
>(sym
)->set_symsize(data_size
);
4577 if (parameters
->doing_static_link()
4578 && (this->plt_
== NULL
|| !this->plt_
->has_irelative_section()))
4580 // If linking statically, make sure that the __rela_iplt symbols
4581 // were defined if necessary, even if we didn't create a PLT.
4582 static const Define_symbol_in_segment syms
[] =
4585 "__rela_iplt_start", // name
4586 elfcpp::PT_LOAD
, // segment_type
4587 elfcpp::PF_W
, // segment_flags_set
4588 elfcpp::PF(0), // segment_flags_clear
4591 elfcpp::STT_NOTYPE
, // type
4592 elfcpp::STB_GLOBAL
, // binding
4593 elfcpp::STV_HIDDEN
, // visibility
4595 Symbol::SEGMENT_START
, // offset_from_base
4599 "__rela_iplt_end", // name
4600 elfcpp::PT_LOAD
, // segment_type
4601 elfcpp::PF_W
, // segment_flags_set
4602 elfcpp::PF(0), // segment_flags_clear
4605 elfcpp::STT_NOTYPE
, // type
4606 elfcpp::STB_GLOBAL
, // binding
4607 elfcpp::STV_HIDDEN
, // visibility
4609 Symbol::SEGMENT_START
, // offset_from_base
4614 symtab
->define_symbols(layout
, 2, syms
,
4615 layout
->script_options()->saw_sections_clause());
4619 // For x32, we need to handle PC-relative relocations using full 64-bit
4620 // arithmetic, so that we can detect relocation overflows properly.
4621 // This class overrides the pcrela32_check methods from the defaults in
4622 // Relocate_functions in reloc.h.
4625 class X86_64_relocate_functions
: public Relocate_functions
<size
, false>
4628 typedef Relocate_functions
<size
, false> Base
;
4630 // Do a simple PC relative relocation with the addend in the
4632 static inline typename
Base::Reloc_status
4633 pcrela32_check(unsigned char* view
,
4634 typename
elfcpp::Elf_types
<64>::Elf_Addr value
,
4635 typename
elfcpp::Elf_types
<64>::Elf_Swxword addend
,
4636 typename
elfcpp::Elf_types
<64>::Elf_Addr address
)
4638 typedef typename
elfcpp::Swap
<32, false>::Valtype Valtype
;
4639 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
4640 value
= value
+ addend
- address
;
4641 elfcpp::Swap
<32, false>::writeval(wv
, value
);
4642 return (Bits
<32>::has_overflow(value
)
4643 ? Base::RELOC_OVERFLOW
: Base::RELOC_OK
);
4646 // Do a simple PC relative relocation with a Symbol_value with the
4647 // addend in the relocation.
4648 static inline typename
Base::Reloc_status
4649 pcrela32_check(unsigned char* view
,
4650 const Sized_relobj_file
<size
, false>* object
,
4651 const Symbol_value
<size
>* psymval
,
4652 typename
elfcpp::Elf_types
<64>::Elf_Swxword addend
,
4653 typename
elfcpp::Elf_types
<64>::Elf_Addr address
)
4655 typedef typename
elfcpp::Swap
<32, false>::Valtype Valtype
;
4656 Valtype
* wv
= reinterpret_cast<Valtype
*>(view
);
4657 typename
elfcpp::Elf_types
<64>::Elf_Addr value
;
4659 value
= psymval
->value(object
, addend
);
4662 // For negative addends, get the symbol value without
4663 // the addend, then add the addend using 64-bit arithmetic.
4664 value
= psymval
->value(object
, 0);
4668 elfcpp::Swap
<32, false>::writeval(wv
, value
);
4669 return (Bits
<32>::has_overflow(value
)
4670 ? Base::RELOC_OVERFLOW
: Base::RELOC_OK
);
4674 // Perform a relocation.
4678 Target_x86_64
<size
>::Relocate::relocate(
4679 const Relocate_info
<size
, false>* relinfo
,
4681 Target_x86_64
<size
>* target
,
4684 const unsigned char* preloc
,
4685 const Sized_symbol
<size
>* gsym
,
4686 const Symbol_value
<size
>* psymval
,
4687 unsigned char* view
,
4688 typename
elfcpp::Elf_types
<size
>::Elf_Addr address
,
4689 section_size_type view_size
)
4691 typedef X86_64_relocate_functions
<size
> Reloc_funcs
;
4692 const elfcpp::Rela
<size
, false> rela(preloc
);
4693 unsigned int r_type
= elfcpp::elf_r_type
<size
>(rela
.get_r_info());
4695 if (this->skip_call_tls_get_addr_
)
4697 if ((r_type
!= elfcpp::R_X86_64_PLT32
4698 && r_type
!= elfcpp::R_X86_64_GOTPCREL
4699 && r_type
!= elfcpp::R_X86_64_GOTPCRELX
4700 && r_type
!= elfcpp::R_X86_64_PLT32_BND
4701 && r_type
!= elfcpp::R_X86_64_PC32_BND
4702 && r_type
!= elfcpp::R_X86_64_PC32
)
4704 || strcmp(gsym
->name(), "__tls_get_addr") != 0)
4706 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
4707 _("missing expected TLS relocation"));
4708 this->skip_call_tls_get_addr_
= false;
4712 this->skip_call_tls_get_addr_
= false;
4720 const Sized_relobj_file
<size
, false>* object
= relinfo
->object
;
4722 // Pick the value to use for symbols defined in the PLT.
4723 Symbol_value
<size
> symval
;
4725 && gsym
->use_plt_offset(Scan::get_reference_flags(r_type
)))
4727 symval
.set_output_value(target
->plt_address_for_global(gsym
));
4730 else if (gsym
== NULL
&& psymval
->is_ifunc_symbol())
4732 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(rela
.get_r_info());
4733 if (object
->local_has_plt_offset(r_sym
))
4735 symval
.set_output_value(target
->plt_address_for_local(object
, r_sym
));
4740 const elfcpp::Elf_Xword addend
= rela
.get_r_addend();
4742 // Get the GOT offset if needed.
4743 // The GOT pointer points to the end of the GOT section.
4744 // We need to subtract the size of the GOT section to get
4745 // the actual offset to use in the relocation.
4746 bool have_got_offset
= false;
4747 // Since the actual offset is always negative, we use signed int to
4748 // support 64-bit GOT relocations.
4752 case elfcpp::R_X86_64_GOT32
:
4753 case elfcpp::R_X86_64_GOT64
:
4754 case elfcpp::R_X86_64_GOTPLT64
:
4755 case elfcpp::R_X86_64_GOTPCREL64
:
4758 gold_assert(gsym
->has_got_offset(GOT_TYPE_STANDARD
));
4759 got_offset
= gsym
->got_offset(GOT_TYPE_STANDARD
) - target
->got_size();
4763 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(rela
.get_r_info());
4764 gold_assert(object
->local_has_got_offset(r_sym
, GOT_TYPE_STANDARD
));
4765 got_offset
= (object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
)
4766 - target
->got_size());
4768 have_got_offset
= true;
4775 typename
Reloc_funcs::Reloc_status rstatus
= Reloc_funcs::RELOC_OK
;
4779 case elfcpp::R_X86_64_NONE
:
4780 case elfcpp::R_X86_64_GNU_VTINHERIT
:
4781 case elfcpp::R_X86_64_GNU_VTENTRY
:
4784 case elfcpp::R_X86_64_64
:
4785 Reloc_funcs::rela64(view
, object
, psymval
, addend
);
4788 case elfcpp::R_X86_64_PC64
:
4789 Reloc_funcs::pcrela64(view
, object
, psymval
, addend
,
4793 case elfcpp::R_X86_64_32
:
4794 rstatus
= Reloc_funcs::rela32_check(view
, object
, psymval
, addend
,
4795 Reloc_funcs::CHECK_UNSIGNED
);
4798 case elfcpp::R_X86_64_32S
:
4799 rstatus
= Reloc_funcs::rela32_check(view
, object
, psymval
, addend
,
4800 Reloc_funcs::CHECK_SIGNED
);
4803 case elfcpp::R_X86_64_PC32
:
4804 case elfcpp::R_X86_64_PC32_BND
:
4805 rstatus
= Reloc_funcs::pcrela32_check(view
, object
, psymval
, addend
,
4809 case elfcpp::R_X86_64_16
:
4810 Reloc_funcs::rela16(view
, object
, psymval
, addend
);
4813 case elfcpp::R_X86_64_PC16
:
4814 Reloc_funcs::pcrela16(view
, object
, psymval
, addend
, address
);
4817 case elfcpp::R_X86_64_8
:
4818 Reloc_funcs::rela8(view
, object
, psymval
, addend
);
4821 case elfcpp::R_X86_64_PC8
:
4822 Reloc_funcs::pcrela8(view
, object
, psymval
, addend
, address
);
4825 case elfcpp::R_X86_64_PLT32
:
4826 case elfcpp::R_X86_64_PLT32_BND
:
4827 gold_assert(gsym
== NULL
4828 || gsym
->has_plt_offset()
4829 || gsym
->final_value_is_known()
4830 || (gsym
->is_defined()
4831 && !gsym
->is_from_dynobj()
4832 && !gsym
->is_preemptible()));
4833 // Note: while this code looks the same as for R_X86_64_PC32, it
4834 // behaves differently because psymval was set to point to
4835 // the PLT entry, rather than the symbol, in Scan::global().
4836 rstatus
= Reloc_funcs::pcrela32_check(view
, object
, psymval
, addend
,
4840 case elfcpp::R_X86_64_PLTOFF64
:
4843 gold_assert(gsym
->has_plt_offset()
4844 || gsym
->final_value_is_known());
4845 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
;
4846 // This is the address of GLOBAL_OFFSET_TABLE.
4847 got_address
= target
->got_plt_section()->address();
4848 Reloc_funcs::rela64(view
, object
, psymval
, addend
- got_address
);
4852 case elfcpp::R_X86_64_GOT32
:
4853 gold_assert(have_got_offset
);
4854 Reloc_funcs::rela32(view
, got_offset
, addend
);
4857 case elfcpp::R_X86_64_GOTPC32
:
4860 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
;
4861 value
= target
->got_plt_section()->address();
4862 Reloc_funcs::pcrela32_check(view
, value
, addend
, address
);
4866 case elfcpp::R_X86_64_GOT64
:
4867 case elfcpp::R_X86_64_GOTPLT64
:
4868 // R_X86_64_GOTPLT64 is obsolete and treated the same as
4870 gold_assert(have_got_offset
);
4871 Reloc_funcs::rela64(view
, got_offset
, addend
);
4874 case elfcpp::R_X86_64_GOTPC64
:
4877 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
;
4878 value
= target
->got_plt_section()->address();
4879 Reloc_funcs::pcrela64(view
, value
, addend
, address
);
4883 case elfcpp::R_X86_64_GOTOFF64
:
4885 typename
elfcpp::Elf_types
<size
>::Elf_Addr reladdr
;
4886 reladdr
= target
->got_plt_section()->address();
4887 Reloc_funcs::pcrela64(view
, object
, psymval
, addend
, reladdr
);
4891 case elfcpp::R_X86_64_GOTPCREL
:
4892 case elfcpp::R_X86_64_GOTPCRELX
:
4893 case elfcpp::R_X86_64_REX_GOTPCRELX
:
4895 bool converted_p
= false;
4897 if (rela
.get_r_addend() == -4)
4900 // mov foo@GOTPCREL(%rip), %reg
4901 // to lea foo(%rip), %reg.
4903 if (!parameters
->incremental()
4905 && rela
.get_r_offset() >= 2
4907 && !psymval
->is_ifunc_symbol())
4909 && rela
.get_r_offset() >= 2
4910 && Target_x86_64
<size
>::can_convert_mov_to_lea(gsym
,
4916 Reloc_funcs::pcrela32(view
, object
, psymval
, addend
, address
);
4920 // callq *foo@GOTPCRELX(%rip) to
4922 // and jmpq *foo@GOTPCRELX(%rip) to
4925 else if (!parameters
->incremental()
4927 && rela
.get_r_offset() >= 2
4928 && Target_x86_64
<size
>::can_convert_callq_to_direct(gsym
,
4933 if (view
[-1] == 0x15)
4935 // Convert callq *foo@GOTPCRELX(%rip) to addr32 callq.
4936 // Opcode of addr32 is 0x67 and opcode of direct callq
4940 // Convert GOTPCRELX to 32-bit pc relative reloc.
4941 Reloc_funcs::pcrela32(view
, object
, psymval
, addend
,
4947 // Convert jmpq *foo@GOTPCRELX(%rip) to
4950 // The opcode of direct jmpq is 0xe9.
4952 // The opcode of nop is 0x90.
4954 // Convert GOTPCRELX to 32-bit pc relative reloc. jmpq
4955 // is rip relative and since the instruction following
4956 // the jmpq is now the nop, offset the address by 1
4957 // byte. The start of the relocation also moves ahead
4959 Reloc_funcs::pcrela32(&view
[-1], object
, psymval
, addend
,
4970 gold_assert(gsym
->has_got_offset(GOT_TYPE_STANDARD
));
4971 got_offset
= (gsym
->got_offset(GOT_TYPE_STANDARD
)
4972 - target
->got_size());
4976 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(rela
.get_r_info());
4977 gold_assert(object
->local_has_got_offset(r_sym
,
4978 GOT_TYPE_STANDARD
));
4979 got_offset
= (object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
)
4980 - target
->got_size());
4982 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
;
4983 value
= target
->got_plt_section()->address() + got_offset
;
4984 Reloc_funcs::pcrela32_check(view
, value
, addend
, address
);
4989 case elfcpp::R_X86_64_GOTPCREL64
:
4991 gold_assert(have_got_offset
);
4992 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
;
4993 value
= target
->got_plt_section()->address() + got_offset
;
4994 Reloc_funcs::pcrela64(view
, value
, addend
, address
);
4998 case elfcpp::R_X86_64_COPY
:
4999 case elfcpp::R_X86_64_GLOB_DAT
:
5000 case elfcpp::R_X86_64_JUMP_SLOT
:
5001 case elfcpp::R_X86_64_RELATIVE
:
5002 case elfcpp::R_X86_64_IRELATIVE
:
5003 // These are outstanding tls relocs, which are unexpected when linking
5004 case elfcpp::R_X86_64_TPOFF64
:
5005 case elfcpp::R_X86_64_DTPMOD64
:
5006 case elfcpp::R_X86_64_TLSDESC
:
5007 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
5008 _("unexpected reloc %u in object file"),
5012 // These are initial tls relocs, which are expected when linking
5013 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
5014 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
5015 case elfcpp::R_X86_64_TLSDESC_CALL
:
5016 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
5017 case elfcpp::R_X86_64_DTPOFF32
:
5018 case elfcpp::R_X86_64_DTPOFF64
:
5019 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
5020 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
5021 this->relocate_tls(relinfo
, target
, relnum
, rela
, r_type
, gsym
, psymval
,
5022 view
, address
, view_size
);
5025 case elfcpp::R_X86_64_SIZE32
:
5026 case elfcpp::R_X86_64_SIZE64
:
5028 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
5029 _("unsupported reloc %u"),
5034 if (rstatus
== Reloc_funcs::RELOC_OVERFLOW
)
5038 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(rela
.get_r_info());
5039 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
5040 _("relocation overflow: "
5041 "reference to local symbol %u in %s"),
5042 r_sym
, object
->name().c_str());
5044 else if (gsym
->is_defined() && gsym
->source() == Symbol::FROM_OBJECT
)
5046 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
5047 _("relocation overflow: "
5048 "reference to '%s' defined in %s"),
5050 gsym
->object()->name().c_str());
5054 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
5055 _("relocation overflow: reference to '%s'"),
5063 // Perform a TLS relocation.
5067 Target_x86_64
<size
>::Relocate::relocate_tls(
5068 const Relocate_info
<size
, false>* relinfo
,
5069 Target_x86_64
<size
>* target
,
5071 const elfcpp::Rela
<size
, false>& rela
,
5072 unsigned int r_type
,
5073 const Sized_symbol
<size
>* gsym
,
5074 const Symbol_value
<size
>* psymval
,
5075 unsigned char* view
,
5076 typename
elfcpp::Elf_types
<size
>::Elf_Addr address
,
5077 section_size_type view_size
)
5079 Output_segment
* tls_segment
= relinfo
->layout
->tls_segment();
5081 const Sized_relobj_file
<size
, false>* object
= relinfo
->object
;
5082 const elfcpp::Elf_Xword addend
= rela
.get_r_addend();
5083 elfcpp::Shdr
<size
, false> data_shdr(relinfo
->data_shdr
);
5084 bool is_executable
= (data_shdr
.get_sh_flags() & elfcpp::SHF_EXECINSTR
) != 0;
5086 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
= psymval
->value(relinfo
->object
, 0);
5088 const bool is_final
= (gsym
== NULL
5089 ? !parameters
->options().shared()
5090 : gsym
->final_value_is_known());
5091 tls::Tls_optimization optimized_type
5092 = Target_x86_64
<size
>::optimize_tls_reloc(is_final
, r_type
);
5095 case elfcpp::R_X86_64_TLSGD
: // Global-dynamic
5096 if (!is_executable
&& optimized_type
== tls::TLSOPT_TO_LE
)
5098 // If this code sequence is used in a non-executable section,
5099 // we will not optimize the R_X86_64_DTPOFF32/64 relocation,
5100 // on the assumption that it's being used by itself in a debug
5101 // section. Therefore, in the unlikely event that the code
5102 // sequence appears in a non-executable section, we simply
5103 // leave it unoptimized.
5104 optimized_type
= tls::TLSOPT_NONE
;
5106 if (optimized_type
== tls::TLSOPT_TO_LE
)
5108 if (tls_segment
== NULL
)
5110 gold_assert(parameters
->errors()->error_count() > 0
5111 || issue_undefined_symbol_error(gsym
));
5114 this->tls_gd_to_le(relinfo
, relnum
, tls_segment
,
5115 rela
, r_type
, value
, view
,
5121 unsigned int got_type
= (optimized_type
== tls::TLSOPT_TO_IE
5122 ? GOT_TYPE_TLS_OFFSET
5123 : GOT_TYPE_TLS_PAIR
);
5124 unsigned int got_offset
;
5127 gold_assert(gsym
->has_got_offset(got_type
));
5128 got_offset
= gsym
->got_offset(got_type
) - target
->got_size();
5132 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(rela
.get_r_info());
5133 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
5134 got_offset
= (object
->local_got_offset(r_sym
, got_type
)
5135 - target
->got_size());
5137 if (optimized_type
== tls::TLSOPT_TO_IE
)
5139 value
= target
->got_plt_section()->address() + got_offset
;
5140 this->tls_gd_to_ie(relinfo
, relnum
, rela
, r_type
,
5141 value
, view
, address
, view_size
);
5144 else if (optimized_type
== tls::TLSOPT_NONE
)
5146 // Relocate the field with the offset of the pair of GOT
5148 value
= target
->got_plt_section()->address() + got_offset
;
5149 Relocate_functions
<size
, false>::pcrela32(view
, value
, addend
,
5154 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
5155 _("unsupported reloc %u"), r_type
);
5158 case elfcpp::R_X86_64_GOTPC32_TLSDESC
: // Global-dynamic (from ~oliva url)
5159 case elfcpp::R_X86_64_TLSDESC_CALL
:
5160 if (!is_executable
&& optimized_type
== tls::TLSOPT_TO_LE
)
5162 // See above comment for R_X86_64_TLSGD.
5163 optimized_type
= tls::TLSOPT_NONE
;
5165 if (optimized_type
== tls::TLSOPT_TO_LE
)
5167 if (tls_segment
== NULL
)
5169 gold_assert(parameters
->errors()->error_count() > 0
5170 || issue_undefined_symbol_error(gsym
));
5173 this->tls_desc_gd_to_le(relinfo
, relnum
, tls_segment
,
5174 rela
, r_type
, value
, view
,
5180 unsigned int got_type
= (optimized_type
== tls::TLSOPT_TO_IE
5181 ? GOT_TYPE_TLS_OFFSET
5182 : GOT_TYPE_TLS_DESC
);
5183 unsigned int got_offset
= 0;
5184 if (r_type
== elfcpp::R_X86_64_GOTPC32_TLSDESC
5185 && optimized_type
== tls::TLSOPT_NONE
)
5187 // We created GOT entries in the .got.tlsdesc portion of
5188 // the .got.plt section, but the offset stored in the
5189 // symbol is the offset within .got.tlsdesc.
5190 got_offset
= (target
->got_size()
5191 + target
->got_plt_section()->data_size());
5195 gold_assert(gsym
->has_got_offset(got_type
));
5196 got_offset
+= gsym
->got_offset(got_type
) - target
->got_size();
5200 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(rela
.get_r_info());
5201 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
5202 got_offset
+= (object
->local_got_offset(r_sym
, got_type
)
5203 - target
->got_size());
5205 if (optimized_type
== tls::TLSOPT_TO_IE
)
5207 value
= target
->got_plt_section()->address() + got_offset
;
5208 this->tls_desc_gd_to_ie(relinfo
, relnum
,
5209 rela
, r_type
, value
, view
, address
,
5213 else if (optimized_type
== tls::TLSOPT_NONE
)
5215 if (r_type
== elfcpp::R_X86_64_GOTPC32_TLSDESC
)
5217 // Relocate the field with the offset of the pair of GOT
5219 value
= target
->got_plt_section()->address() + got_offset
;
5220 Relocate_functions
<size
, false>::pcrela32(view
, value
, addend
,
5226 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
5227 _("unsupported reloc %u"), r_type
);
5230 case elfcpp::R_X86_64_TLSLD
: // Local-dynamic
5231 if (!is_executable
&& optimized_type
== tls::TLSOPT_TO_LE
)
5233 // See above comment for R_X86_64_TLSGD.
5234 optimized_type
= tls::TLSOPT_NONE
;
5236 if (optimized_type
== tls::TLSOPT_TO_LE
)
5238 if (tls_segment
== NULL
)
5240 gold_assert(parameters
->errors()->error_count() > 0
5241 || issue_undefined_symbol_error(gsym
));
5244 this->tls_ld_to_le(relinfo
, relnum
, tls_segment
, rela
, r_type
,
5245 value
, view
, view_size
);
5248 else if (optimized_type
== tls::TLSOPT_NONE
)
5250 // Relocate the field with the offset of the GOT entry for
5251 // the module index.
5252 unsigned int got_offset
;
5253 got_offset
= (target
->got_mod_index_entry(NULL
, NULL
, NULL
)
5254 - target
->got_size());
5255 value
= target
->got_plt_section()->address() + got_offset
;
5256 Relocate_functions
<size
, false>::pcrela32(view
, value
, addend
,
5260 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
5261 _("unsupported reloc %u"), r_type
);
5264 case elfcpp::R_X86_64_DTPOFF32
:
5265 // This relocation type is used in debugging information.
5266 // In that case we need to not optimize the value. If the
5267 // section is not executable, then we assume we should not
5268 // optimize this reloc. See comments above for R_X86_64_TLSGD,
5269 // R_X86_64_GOTPC32_TLSDESC, R_X86_64_TLSDESC_CALL, and
5271 if (optimized_type
== tls::TLSOPT_TO_LE
&& is_executable
)
5273 if (tls_segment
== NULL
)
5275 gold_assert(parameters
->errors()->error_count() > 0
5276 || issue_undefined_symbol_error(gsym
));
5279 value
-= tls_segment
->memsz();
5281 Relocate_functions
<size
, false>::rela32(view
, value
, addend
);
5284 case elfcpp::R_X86_64_DTPOFF64
:
5285 // See R_X86_64_DTPOFF32, just above, for why we check for is_executable.
5286 if (optimized_type
== tls::TLSOPT_TO_LE
&& is_executable
)
5288 if (tls_segment
== NULL
)
5290 gold_assert(parameters
->errors()->error_count() > 0
5291 || issue_undefined_symbol_error(gsym
));
5294 value
-= tls_segment
->memsz();
5296 Relocate_functions
<size
, false>::rela64(view
, value
, addend
);
5299 case elfcpp::R_X86_64_GOTTPOFF
: // Initial-exec
5301 && gsym
->is_undefined()
5302 && parameters
->options().output_is_executable())
5304 Target_x86_64
<size
>::Relocate::tls_ie_to_le(relinfo
, relnum
,
5306 r_type
, value
, view
,
5310 else if (optimized_type
== tls::TLSOPT_TO_LE
)
5312 if (tls_segment
== NULL
)
5314 gold_assert(parameters
->errors()->error_count() > 0
5315 || issue_undefined_symbol_error(gsym
));
5318 Target_x86_64
<size
>::Relocate::tls_ie_to_le(relinfo
, relnum
,
5320 r_type
, value
, view
,
5324 else if (optimized_type
== tls::TLSOPT_NONE
)
5326 // Relocate the field with the offset of the GOT entry for
5327 // the tp-relative offset of the symbol.
5328 unsigned int got_offset
;
5331 gold_assert(gsym
->has_got_offset(GOT_TYPE_TLS_OFFSET
));
5332 got_offset
= (gsym
->got_offset(GOT_TYPE_TLS_OFFSET
)
5333 - target
->got_size());
5337 unsigned int r_sym
= elfcpp::elf_r_sym
<size
>(rela
.get_r_info());
5338 gold_assert(object
->local_has_got_offset(r_sym
,
5339 GOT_TYPE_TLS_OFFSET
));
5340 got_offset
= (object
->local_got_offset(r_sym
, GOT_TYPE_TLS_OFFSET
)
5341 - target
->got_size());
5343 value
= target
->got_plt_section()->address() + got_offset
;
5344 Relocate_functions
<size
, false>::pcrela32(view
, value
, addend
,
5348 gold_error_at_location(relinfo
, relnum
, rela
.get_r_offset(),
5349 _("unsupported reloc type %u"),
5353 case elfcpp::R_X86_64_TPOFF32
: // Local-exec
5354 if (tls_segment
== NULL
)
5356 gold_assert(parameters
->errors()->error_count() > 0
5357 || issue_undefined_symbol_error(gsym
));
5360 value
-= tls_segment
->memsz();
5361 Relocate_functions
<size
, false>::rela32(view
, value
, addend
);
5366 // Do a relocation in which we convert a TLS General-Dynamic to an
5371 Target_x86_64
<size
>::Relocate::tls_gd_to_ie(
5372 const Relocate_info
<size
, false>* relinfo
,
5374 const elfcpp::Rela
<size
, false>& rela
,
5376 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
5377 unsigned char* view
,
5378 typename
elfcpp::Elf_types
<size
>::Elf_Addr address
,
5379 section_size_type view_size
)
5382 // .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
5383 // .word 0x6666; rex64; call __tls_get_addr@PLT
5384 // ==> movq %fs:0,%rax; addq x@gottpoff(%rip),%rax
5385 // .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
5386 // .word 0x66; rex64; call *__tls_get_addr@GOTPCREL(%rip)
5387 // ==> movq %fs:0,%rax; addq x@gottpoff(%rip),%rax
5389 // leaq foo@tlsgd(%rip),%rdi;
5390 // .word 0x6666; rex64; call __tls_get_addr@PLT
5391 // ==> movl %fs:0,%eax; addq x@gottpoff(%rip),%rax
5392 // leaq foo@tlsgd(%rip),%rdi;
5393 // .word 0x66; rex64; call *__tls_get_addr@GOTPCREL(%rip)
5394 // ==> movl %fs:0,%eax; addq x@gottpoff(%rip),%rax
5396 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 12);
5397 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
5398 (memcmp(view
+ 4, "\x66\x66\x48\xe8", 4) == 0
5399 || memcmp(view
+ 4, "\x66\x48\xff", 3) == 0));
5403 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
,
5405 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
5406 (memcmp(view
- 4, "\x66\x48\x8d\x3d", 4) == 0));
5407 memcpy(view
- 4, "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x03\x05\0\0\0\0",
5412 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
,
5414 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
5415 (memcmp(view
- 3, "\x48\x8d\x3d", 3) == 0));
5416 memcpy(view
- 3, "\x64\x8b\x04\x25\0\0\0\0\x48\x03\x05\0\0\0\0",
5420 const elfcpp::Elf_Xword addend
= rela
.get_r_addend();
5421 Relocate_functions
<size
, false>::pcrela32(view
+ 8, value
, addend
- 8,
5424 // The next reloc should be a PLT32 reloc against __tls_get_addr.
5426 this->skip_call_tls_get_addr_
= true;
5429 // Do a relocation in which we convert a TLS General-Dynamic to a
5434 Target_x86_64
<size
>::Relocate::tls_gd_to_le(
5435 const Relocate_info
<size
, false>* relinfo
,
5437 Output_segment
* tls_segment
,
5438 const elfcpp::Rela
<size
, false>& rela
,
5440 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
5441 unsigned char* view
,
5442 section_size_type view_size
)
5445 // .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
5446 // .word 0x6666; rex64; call __tls_get_addr@PLT
5447 // ==> movq %fs:0,%rax; leaq x@tpoff(%rax),%rax
5448 // .byte 0x66; leaq foo@tlsgd(%rip),%rdi;
5449 // .word 0x66; rex64; call *__tls_get_addr@GOTPCREL(%rip)
5450 // ==> movq %fs:0,%rax; leaq x@tpoff(%rax),%rax
5452 // leaq foo@tlsgd(%rip),%rdi;
5453 // .word 0x6666; rex64; call __tls_get_addr@PLT
5454 // ==> movl %fs:0,%eax; leaq x@tpoff(%rax),%rax
5455 // leaq foo@tlsgd(%rip),%rdi;
5456 // .word 0x66; rex64; call *__tls_get_addr@GOTPCREL(%rip)
5457 // ==> movl %fs:0,%eax; leaq x@tpoff(%rax),%rax
5459 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 12);
5460 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
5461 (memcmp(view
+ 4, "\x66\x66\x48\xe8", 4) == 0
5462 || memcmp(view
+ 4, "\x66\x48\xff", 3) == 0));
5466 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
,
5468 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
5469 (memcmp(view
- 4, "\x66\x48\x8d\x3d", 4) == 0));
5470 memcpy(view
- 4, "\x64\x48\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0\0",
5475 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
,
5477 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
5478 (memcmp(view
- 3, "\x48\x8d\x3d", 3) == 0));
5480 memcpy(view
- 3, "\x64\x8b\x04\x25\0\0\0\0\x48\x8d\x80\0\0\0\0",
5484 value
-= tls_segment
->memsz();
5485 Relocate_functions
<size
, false>::rela32(view
+ 8, value
, 0);
5487 // The next reloc should be a PLT32 reloc against __tls_get_addr.
5489 this->skip_call_tls_get_addr_
= true;
5492 // Do a TLSDESC-style General-Dynamic to Initial-Exec transition.
5496 Target_x86_64
<size
>::Relocate::tls_desc_gd_to_ie(
5497 const Relocate_info
<size
, false>* relinfo
,
5499 const elfcpp::Rela
<size
, false>& rela
,
5500 unsigned int r_type
,
5501 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
5502 unsigned char* view
,
5503 typename
elfcpp::Elf_types
<size
>::Elf_Addr address
,
5504 section_size_type view_size
)
5506 if (r_type
== elfcpp::R_X86_64_GOTPC32_TLSDESC
)
5508 // LP64: leaq foo@tlsdesc(%rip), %rax
5509 // ==> movq foo@gottpoff(%rip), %rax
5510 // X32: rex leal foo@tlsdesc(%rip), %eax
5511 // ==> rex movl foo@gottpoff(%rip), %eax
5512 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -3);
5513 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 4);
5514 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
5515 (((view
[-3] & 0xfb) == 0x48
5516 || (size
== 32 && (view
[-3] & 0xfb) == 0x40))
5518 && (view
[-1] & 0xc7) == 0x05));
5520 const elfcpp::Elf_Xword addend
= rela
.get_r_addend();
5521 Relocate_functions
<size
, false>::pcrela32(view
, value
, addend
, address
);
5525 // LP64: call *foo@tlscall(%rax)
5526 // ==> xchg %ax, %ax
5527 // X32: call *foo@tlscall(%eax)
5529 gold_assert(r_type
== elfcpp::R_X86_64_TLSDESC_CALL
);
5530 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 2);
5532 if (size
== 32 && view
[0] == 0x67)
5534 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(),
5538 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
5539 view
[prefix
] == 0xff && view
[prefix
+ 1] == 0x10);
5554 // Do a TLSDESC-style General-Dynamic to Local-Exec transition.
5558 Target_x86_64
<size
>::Relocate::tls_desc_gd_to_le(
5559 const Relocate_info
<size
, false>* relinfo
,
5561 Output_segment
* tls_segment
,
5562 const elfcpp::Rela
<size
, false>& rela
,
5563 unsigned int r_type
,
5564 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
5565 unsigned char* view
,
5566 section_size_type view_size
)
5568 if (r_type
== elfcpp::R_X86_64_GOTPC32_TLSDESC
)
5570 // LP64: leaq foo@tlsdesc(%rip), %rax
5571 // ==> movq foo@tpoff, %rax
5572 // X32: rex leal foo@tlsdesc(%rip), %eax
5573 // ==> rex movl foo@tpoff, %eax
5574 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -3);
5575 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 4);
5576 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
5577 (((view
[-3] & 0xfb) == 0x48
5578 || (size
== 32 && (view
[-3] & 0xfb) == 0x40))
5580 && (view
[-1] & 0xc7) == 0x05));
5581 view
[-3] = (view
[-3] & 0x48) | ((view
[-3] >> 2) & 1);
5583 view
[-1] = 0xc0 | ((view
[-1] >> 3) & 7);
5584 value
-= tls_segment
->memsz();
5585 Relocate_functions
<size
, false>::rela32(view
, value
, 0);
5589 // LP64: call *foo@tlscall(%rax)
5590 // ==> xchg %ax, %ax
5591 // X32: call *foo@tlscall(%eax)
5593 gold_assert(r_type
== elfcpp::R_X86_64_TLSDESC_CALL
);
5594 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 2);
5596 if (size
== 32 && view
[0] == 0x67)
5598 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(),
5602 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
5603 view
[prefix
] == 0xff && view
[prefix
+ 1] == 0x10);
5620 Target_x86_64
<size
>::Relocate::tls_ld_to_le(
5621 const Relocate_info
<size
, false>* relinfo
,
5624 const elfcpp::Rela
<size
, false>& rela
,
5626 typename
elfcpp::Elf_types
<size
>::Elf_Addr
,
5627 unsigned char* view
,
5628 section_size_type view_size
)
5630 // leaq foo@tlsld(%rip),%rdi; call __tls_get_addr@plt;
5632 // ... leq foo@dtpoff(%rax),%reg
5633 // ==> .word 0x6666; .byte 0x66; movq %fs:0,%rax ... leaq x@tpoff(%rax),%rdx
5635 // ... leq foo@dtpoff(%rax),%reg
5636 // ==> nopl 0x0(%rax); movl %fs:0,%eax ... leaq x@tpoff(%rax),%rdx
5637 // leaq foo@tlsld(%rip),%rdi; call *__tls_get_addr@GOTPCREL(%rip)
5639 // ... leq foo@dtpoff(%rax),%reg
5640 // ==> .word 0x6666; .byte 0x6666; movq %fs:0,%rax ... leaq x@tpoff(%rax),%rdx
5642 // ... leq foo@dtpoff(%rax),%reg
5643 // ==> nopw 0x0(%rax); movl %fs:0,%eax ... leaq x@tpoff(%rax),%rdx
5645 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -3);
5646 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 9);
5648 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
5649 view
[-3] == 0x48 && view
[-2] == 0x8d && view
[-1] == 0x3d);
5651 tls::check_tls(relinfo
, relnum
, rela
.get_r_offset(),
5652 view
[4] == 0xe8 || view
[4] == 0xff);
5654 if (view
[4] == 0xe8)
5657 memcpy(view
- 3, "\x66\x66\x66\x64\x48\x8b\x04\x25\0\0\0\0", 12);
5659 memcpy(view
- 3, "\x0f\x1f\x40\x00\x64\x8b\x04\x25\0\0\0\0", 12);
5664 memcpy(view
- 3, "\x66\x66\x66\x66\x64\x48\x8b\x04\x25\0\0\0\0",
5667 memcpy(view
- 3, "\x66\x0f\x1f\x40\x00\x64\x8b\x04\x25\0\0\0\0",
5671 // The next reloc should be a PLT32 reloc against __tls_get_addr.
5673 this->skip_call_tls_get_addr_
= true;
5676 // Do a relocation in which we convert a TLS Initial-Exec to a
5681 Target_x86_64
<size
>::Relocate::tls_ie_to_le(
5682 const Relocate_info
<size
, false>* relinfo
,
5684 Output_segment
* tls_segment
,
5685 const elfcpp::Rela
<size
, false>& rela
,
5687 typename
elfcpp::Elf_types
<size
>::Elf_Addr value
,
5688 unsigned char* view
,
5689 section_size_type view_size
)
5691 // We need to examine the opcodes to figure out which instruction we
5694 // movq foo@gottpoff(%rip),%reg ==> movq $YY,%reg
5695 // addq foo@gottpoff(%rip),%reg ==> addq $YY,%reg
5697 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, -3);
5698 tls::check_range(relinfo
, relnum
, rela
.get_r_offset(), view_size
, 4);
5700 unsigned char op1
= view
[-3];
5701 unsigned char op2
= view
[-2];
5702 unsigned char op3
= view
[-1];
5703 unsigned char reg
= op3
>> 3;
5710 else if (size
== 32 && op1
== 0x44)
5713 view
[-1] = 0xc0 | reg
;
5717 // Special handling for %rsp.
5720 else if (size
== 32 && op1
== 0x44)
5723 view
[-1] = 0xc0 | reg
;
5730 else if (size
== 32 && op1
== 0x44)
5733 view
[-1] = 0x80 | reg
| (reg
<< 3);
5736 if (tls_segment
!= NULL
)
5737 value
-= tls_segment
->memsz();
5738 Relocate_functions
<size
, false>::rela32(view
, value
, 0);
5741 // Relocate section data.
5745 Target_x86_64
<size
>::relocate_section(
5746 const Relocate_info
<size
, false>* relinfo
,
5747 unsigned int sh_type
,
5748 const unsigned char* prelocs
,
5750 Output_section
* output_section
,
5751 bool needs_special_offset_handling
,
5752 unsigned char* view
,
5753 typename
elfcpp::Elf_types
<size
>::Elf_Addr address
,
5754 section_size_type view_size
,
5755 const Reloc_symbol_changes
* reloc_symbol_changes
)
5757 typedef gold::Default_classify_reloc
<elfcpp::SHT_RELA
, size
, false>
5760 gold_assert(sh_type
== elfcpp::SHT_RELA
);
5762 gold::relocate_section
<size
, false, Target_x86_64
<size
>, Relocate
,
5763 gold::Default_comdat_behavior
, Classify_reloc
>(
5769 needs_special_offset_handling
,
5773 reloc_symbol_changes
);
5776 // Apply an incremental relocation. Incremental relocations always refer
5777 // to global symbols.
5781 Target_x86_64
<size
>::apply_relocation(
5782 const Relocate_info
<size
, false>* relinfo
,
5783 typename
elfcpp::Elf_types
<size
>::Elf_Addr r_offset
,
5784 unsigned int r_type
,
5785 typename
elfcpp::Elf_types
<size
>::Elf_Swxword r_addend
,
5787 unsigned char* view
,
5788 typename
elfcpp::Elf_types
<size
>::Elf_Addr address
,
5789 section_size_type view_size
)
5791 gold::apply_relocation
<size
, false, Target_x86_64
<size
>,
5792 typename Target_x86_64
<size
>::Relocate
>(
5804 // Scan the relocs during a relocatable link.
5808 Target_x86_64
<size
>::scan_relocatable_relocs(
5809 Symbol_table
* symtab
,
5811 Sized_relobj_file
<size
, false>* object
,
5812 unsigned int data_shndx
,
5813 unsigned int sh_type
,
5814 const unsigned char* prelocs
,
5816 Output_section
* output_section
,
5817 bool needs_special_offset_handling
,
5818 size_t local_symbol_count
,
5819 const unsigned char* plocal_symbols
,
5820 Relocatable_relocs
* rr
)
5822 typedef gold::Default_classify_reloc
<elfcpp::SHT_RELA
, size
, false>
5824 typedef gold::Default_scan_relocatable_relocs
<Classify_reloc
>
5825 Scan_relocatable_relocs
;
5827 gold_assert(sh_type
== elfcpp::SHT_RELA
);
5829 gold::scan_relocatable_relocs
<size
, false, Scan_relocatable_relocs
>(
5837 needs_special_offset_handling
,
5843 // Scan the relocs for --emit-relocs.
5847 Target_x86_64
<size
>::emit_relocs_scan(
5848 Symbol_table
* symtab
,
5850 Sized_relobj_file
<size
, false>* object
,
5851 unsigned int data_shndx
,
5852 unsigned int sh_type
,
5853 const unsigned char* prelocs
,
5855 Output_section
* output_section
,
5856 bool needs_special_offset_handling
,
5857 size_t local_symbol_count
,
5858 const unsigned char* plocal_syms
,
5859 Relocatable_relocs
* rr
)
5861 typedef gold::Default_classify_reloc
<elfcpp::SHT_RELA
, size
, false>
5863 typedef gold::Default_emit_relocs_strategy
<Classify_reloc
>
5864 Emit_relocs_strategy
;
5866 gold_assert(sh_type
== elfcpp::SHT_RELA
);
5868 gold::scan_relocatable_relocs
<size
, false, Emit_relocs_strategy
>(
5876 needs_special_offset_handling
,
5882 // Relocate a section during a relocatable link.
5886 Target_x86_64
<size
>::relocate_relocs(
5887 const Relocate_info
<size
, false>* relinfo
,
5888 unsigned int sh_type
,
5889 const unsigned char* prelocs
,
5891 Output_section
* output_section
,
5892 typename
elfcpp::Elf_types
<size
>::Elf_Off offset_in_output_section
,
5893 unsigned char* view
,
5894 typename
elfcpp::Elf_types
<size
>::Elf_Addr view_address
,
5895 section_size_type view_size
,
5896 unsigned char* reloc_view
,
5897 section_size_type reloc_view_size
)
5899 typedef gold::Default_classify_reloc
<elfcpp::SHT_RELA
, size
, false>
5902 gold_assert(sh_type
== elfcpp::SHT_RELA
);
5904 gold::relocate_relocs
<size
, false, Classify_reloc
>(
5909 offset_in_output_section
,
5917 // Return the value to use for a dynamic which requires special
5918 // treatment. This is how we support equality comparisons of function
5919 // pointers across shared library boundaries, as described in the
5920 // processor specific ABI supplement.
5924 Target_x86_64
<size
>::do_dynsym_value(const Symbol
* gsym
) const
5926 gold_assert(gsym
->is_from_dynobj() && gsym
->has_plt_offset());
5927 return this->plt_address_for_global(gsym
);
5930 // Return a string used to fill a code section with nops to take up
5931 // the specified length.
5935 Target_x86_64
<size
>::do_code_fill(section_size_type length
) const
5939 // Build a jmpq instruction to skip over the bytes.
5940 unsigned char jmp
[5];
5942 elfcpp::Swap_unaligned
<32, false>::writeval(jmp
+ 1, length
- 5);
5943 return (std::string(reinterpret_cast<char*>(&jmp
[0]), 5)
5944 + std::string(length
- 5, static_cast<char>(0x90)));
5947 // Nop sequences of various lengths.
5948 const char nop1
[1] = { '\x90' }; // nop
5949 const char nop2
[2] = { '\x66', '\x90' }; // xchg %ax %ax
5950 const char nop3
[3] = { '\x0f', '\x1f', '\x00' }; // nop (%rax)
5951 const char nop4
[4] = { '\x0f', '\x1f', '\x40', // nop 0(%rax)
5953 const char nop5
[5] = { '\x0f', '\x1f', '\x44', // nop 0(%rax,%rax,1)
5955 const char nop6
[6] = { '\x66', '\x0f', '\x1f', // nopw 0(%rax,%rax,1)
5956 '\x44', '\x00', '\x00' };
5957 const char nop7
[7] = { '\x0f', '\x1f', '\x80', // nopl 0L(%rax)
5958 '\x00', '\x00', '\x00',
5960 const char nop8
[8] = { '\x0f', '\x1f', '\x84', // nopl 0L(%rax,%rax,1)
5961 '\x00', '\x00', '\x00',
5963 const char nop9
[9] = { '\x66', '\x0f', '\x1f', // nopw 0L(%rax,%rax,1)
5964 '\x84', '\x00', '\x00',
5965 '\x00', '\x00', '\x00' };
5966 const char nop10
[10] = { '\x66', '\x2e', '\x0f', // nopw %cs:0L(%rax,%rax,1)
5967 '\x1f', '\x84', '\x00',
5968 '\x00', '\x00', '\x00',
5970 const char nop11
[11] = { '\x66', '\x66', '\x2e', // data16
5971 '\x0f', '\x1f', '\x84', // nopw %cs:0L(%rax,%rax,1)
5972 '\x00', '\x00', '\x00',
5974 const char nop12
[12] = { '\x66', '\x66', '\x66', // data16; data16
5975 '\x2e', '\x0f', '\x1f', // nopw %cs:0L(%rax,%rax,1)
5976 '\x84', '\x00', '\x00',
5977 '\x00', '\x00', '\x00' };
5978 const char nop13
[13] = { '\x66', '\x66', '\x66', // data16; data16; data16
5979 '\x66', '\x2e', '\x0f', // nopw %cs:0L(%rax,%rax,1)
5980 '\x1f', '\x84', '\x00',
5981 '\x00', '\x00', '\x00',
5983 const char nop14
[14] = { '\x66', '\x66', '\x66', // data16; data16; data16
5984 '\x66', '\x66', '\x2e', // data16
5985 '\x0f', '\x1f', '\x84', // nopw %cs:0L(%rax,%rax,1)
5986 '\x00', '\x00', '\x00',
5988 const char nop15
[15] = { '\x66', '\x66', '\x66', // data16; data16; data16
5989 '\x66', '\x66', '\x66', // data16; data16
5990 '\x2e', '\x0f', '\x1f', // nopw %cs:0L(%rax,%rax,1)
5991 '\x84', '\x00', '\x00',
5992 '\x00', '\x00', '\x00' };
5994 const char* nops
[16] = {
5996 nop1
, nop2
, nop3
, nop4
, nop5
, nop6
, nop7
,
5997 nop8
, nop9
, nop10
, nop11
, nop12
, nop13
, nop14
, nop15
6000 return std::string(nops
[length
], length
);
6003 // Return the addend to use for a target specific relocation. The
6004 // only target specific relocation is R_X86_64_TLSDESC for a local
6005 // symbol. We want to set the addend is the offset of the local
6006 // symbol in the TLS segment.
6010 Target_x86_64
<size
>::do_reloc_addend(void* arg
, unsigned int r_type
,
6013 gold_assert(r_type
== elfcpp::R_X86_64_TLSDESC
);
6014 uintptr_t intarg
= reinterpret_cast<uintptr_t>(arg
);
6015 gold_assert(intarg
< this->tlsdesc_reloc_info_
.size());
6016 const Tlsdesc_info
& ti(this->tlsdesc_reloc_info_
[intarg
]);
6017 const Symbol_value
<size
>* psymval
= ti
.object
->local_symbol(ti
.r_sym
);
6018 gold_assert(psymval
->is_tls_symbol());
6019 // The value of a TLS symbol is the offset in the TLS segment.
6020 return psymval
->value(ti
.object
, 0);
6023 // Return the value to use for the base of a DW_EH_PE_datarel offset
6024 // in an FDE. Solaris and SVR4 use DW_EH_PE_datarel because their
6025 // assembler can not write out the difference between two labels in
6026 // different sections, so instead of using a pc-relative value they
6027 // use an offset from the GOT.
6031 Target_x86_64
<size
>::do_ehframe_datarel_base() const
6033 gold_assert(this->global_offset_table_
!= NULL
);
6034 Symbol
* sym
= this->global_offset_table_
;
6035 Sized_symbol
<size
>* ssym
= static_cast<Sized_symbol
<size
>*>(sym
);
6036 return ssym
->value();
6039 // FNOFFSET in section SHNDX in OBJECT is the start of a function
6040 // compiled with -fsplit-stack. The function calls non-split-stack
6041 // code. We have to change the function so that it always ensures
6042 // that it has enough stack space to run some random function.
6044 static const unsigned char cmp_insn_32
[] = { 0x64, 0x3b, 0x24, 0x25 };
6045 static const unsigned char lea_r10_insn_32
[] = { 0x44, 0x8d, 0x94, 0x24 };
6046 static const unsigned char lea_r11_insn_32
[] = { 0x44, 0x8d, 0x9c, 0x24 };
6048 static const unsigned char cmp_insn_64
[] = { 0x64, 0x48, 0x3b, 0x24, 0x25 };
6049 static const unsigned char lea_r10_insn_64
[] = { 0x4c, 0x8d, 0x94, 0x24 };
6050 static const unsigned char lea_r11_insn_64
[] = { 0x4c, 0x8d, 0x9c, 0x24 };
6054 Target_x86_64
<size
>::do_calls_non_split(Relobj
* object
, unsigned int shndx
,
6055 section_offset_type fnoffset
,
6056 section_size_type fnsize
,
6057 const unsigned char*,
6059 unsigned char* view
,
6060 section_size_type view_size
,
6062 std::string
* to
) const
6064 const char* const cmp_insn
= reinterpret_cast<const char*>
6065 (size
== 32 ? cmp_insn_32
: cmp_insn_64
);
6066 const char* const lea_r10_insn
= reinterpret_cast<const char*>
6067 (size
== 32 ? lea_r10_insn_32
: lea_r10_insn_64
);
6068 const char* const lea_r11_insn
= reinterpret_cast<const char*>
6069 (size
== 32 ? lea_r11_insn_32
: lea_r11_insn_64
);
6071 const size_t cmp_insn_len
=
6072 (size
== 32 ? sizeof(cmp_insn_32
) : sizeof(cmp_insn_64
));
6073 const size_t lea_r10_insn_len
=
6074 (size
== 32 ? sizeof(lea_r10_insn_32
) : sizeof(lea_r10_insn_64
));
6075 const size_t lea_r11_insn_len
=
6076 (size
== 32 ? sizeof(lea_r11_insn_32
) : sizeof(lea_r11_insn_64
));
6077 const size_t nop_len
= (size
== 32 ? 7 : 8);
6079 // The function starts with a comparison of the stack pointer and a
6080 // field in the TCB. This is followed by a jump.
6083 if (this->match_view(view
, view_size
, fnoffset
, cmp_insn
, cmp_insn_len
)
6084 && fnsize
> nop_len
+ 1)
6086 // We will call __morestack if the carry flag is set after this
6087 // comparison. We turn the comparison into an stc instruction
6089 view
[fnoffset
] = '\xf9';
6090 this->set_view_to_nop(view
, view_size
, fnoffset
+ 1, nop_len
);
6092 // lea NN(%rsp),%r10
6093 // lea NN(%rsp),%r11
6094 else if ((this->match_view(view
, view_size
, fnoffset
,
6095 lea_r10_insn
, lea_r10_insn_len
)
6096 || this->match_view(view
, view_size
, fnoffset
,
6097 lea_r11_insn
, lea_r11_insn_len
))
6100 // This is loading an offset from the stack pointer for a
6101 // comparison. The offset is negative, so we decrease the
6102 // offset by the amount of space we need for the stack. This
6103 // means we will avoid calling __morestack if there happens to
6104 // be plenty of space on the stack already.
6105 unsigned char* pval
= view
+ fnoffset
+ 4;
6106 uint32_t val
= elfcpp::Swap_unaligned
<32, false>::readval(pval
);
6107 val
-= parameters
->options().split_stack_adjust_size();
6108 elfcpp::Swap_unaligned
<32, false>::writeval(pval
, val
);
6112 if (!object
->has_no_split_stack())
6113 object
->error(_("failed to match split-stack sequence at "
6114 "section %u offset %0zx"),
6115 shndx
, static_cast<size_t>(fnoffset
));
6119 // We have to change the function so that it calls
6120 // __morestack_non_split instead of __morestack. The former will
6121 // allocate additional stack space.
6122 *from
= "__morestack";
6123 *to
= "__morestack_non_split";
6126 // The selector for x86_64 object files. Note this is never instantiated
6127 // directly. It's only used in Target_selector_x86_64_nacl, below.
6130 class Target_selector_x86_64
: public Target_selector_freebsd
6133 Target_selector_x86_64()
6134 : Target_selector_freebsd(elfcpp::EM_X86_64
, size
, false,
6136 ? "elf64-x86-64" : "elf32-x86-64"),
6138 ? "elf64-x86-64-freebsd"
6139 : "elf32-x86-64-freebsd"),
6140 (size
== 64 ? "elf_x86_64" : "elf32_x86_64"))
6144 do_instantiate_target()
6145 { return new Target_x86_64
<size
>(); }
6149 // NaCl variant. It uses different PLT contents.
6152 class Output_data_plt_x86_64_nacl
: public Output_data_plt_x86_64
<size
>
6155 Output_data_plt_x86_64_nacl(Layout
* layout
,
6156 Output_data_got
<64, false>* got
,
6157 Output_data_got_plt_x86_64
* got_plt
,
6158 Output_data_space
* got_irelative
)
6159 : Output_data_plt_x86_64
<size
>(layout
, plt_entry_size
,
6160 got
, got_plt
, got_irelative
)
6163 Output_data_plt_x86_64_nacl(Layout
* layout
,
6164 Output_data_got
<64, false>* got
,
6165 Output_data_got_plt_x86_64
* got_plt
,
6166 Output_data_space
* got_irelative
,
6167 unsigned int plt_count
)
6168 : Output_data_plt_x86_64
<size
>(layout
, plt_entry_size
,
6169 got
, got_plt
, got_irelative
,
6174 virtual unsigned int
6175 do_get_plt_entry_size() const
6176 { return plt_entry_size
; }
6179 do_add_eh_frame(Layout
* layout
)
6181 layout
->add_eh_frame_for_plt(this,
6182 this->plt_eh_frame_cie
,
6183 this->plt_eh_frame_cie_size
,
6185 plt_eh_frame_fde_size
);
6189 do_fill_first_plt_entry(unsigned char* pov
,
6190 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_addr
,
6191 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_addr
);
6193 virtual unsigned int
6194 do_fill_plt_entry(unsigned char* pov
,
6195 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
6196 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
6197 unsigned int got_offset
,
6198 unsigned int plt_offset
,
6199 unsigned int plt_index
);
6202 do_fill_tlsdesc_entry(unsigned char* pov
,
6203 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
6204 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
6205 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_base
,
6206 unsigned int tlsdesc_got_offset
,
6207 unsigned int plt_offset
);
6210 // The size of an entry in the PLT.
6211 static const int plt_entry_size
= 64;
6213 // The first entry in the PLT.
6214 static const unsigned char first_plt_entry
[plt_entry_size
];
6216 // Other entries in the PLT for an executable.
6217 static const unsigned char plt_entry
[plt_entry_size
];
6219 // The reserved TLSDESC entry in the PLT for an executable.
6220 static const unsigned char tlsdesc_plt_entry
[plt_entry_size
];
6222 // The .eh_frame unwind information for the PLT.
6223 static const int plt_eh_frame_fde_size
= 32;
6224 static const unsigned char plt_eh_frame_fde
[plt_eh_frame_fde_size
];
6228 class Target_x86_64_nacl
: public Target_x86_64
<size
>
6231 Target_x86_64_nacl()
6232 : Target_x86_64
<size
>(&x86_64_nacl_info
)
6235 virtual Output_data_plt_x86_64
<size
>*
6236 do_make_data_plt(Layout
* layout
,
6237 Output_data_got
<64, false>* got
,
6238 Output_data_got_plt_x86_64
* got_plt
,
6239 Output_data_space
* got_irelative
)
6241 return new Output_data_plt_x86_64_nacl
<size
>(layout
, got
, got_plt
,
6245 virtual Output_data_plt_x86_64
<size
>*
6246 do_make_data_plt(Layout
* layout
,
6247 Output_data_got
<64, false>* got
,
6248 Output_data_got_plt_x86_64
* got_plt
,
6249 Output_data_space
* got_irelative
,
6250 unsigned int plt_count
)
6252 return new Output_data_plt_x86_64_nacl
<size
>(layout
, got
, got_plt
,
6258 do_code_fill(section_size_type length
) const;
6261 static const Target::Target_info x86_64_nacl_info
;
6265 const Target::Target_info Target_x86_64_nacl
<64>::x86_64_nacl_info
=
6268 false, // is_big_endian
6269 elfcpp::EM_X86_64
, // machine_code
6270 false, // has_make_symbol
6271 false, // has_resolve
6272 true, // has_code_fill
6273 true, // is_default_stack_executable
6274 true, // can_icf_inline_merge_sections
6276 "/lib64/ld-nacl-x86-64.so.1", // dynamic_linker
6277 0x20000, // default_text_segment_address
6278 0x10000, // abi_pagesize (overridable by -z max-page-size)
6279 0x10000, // common_pagesize (overridable by -z common-page-size)
6280 true, // isolate_execinstr
6281 0x10000000, // rosegment_gap
6282 elfcpp::SHN_UNDEF
, // small_common_shndx
6283 elfcpp::SHN_X86_64_LCOMMON
, // large_common_shndx
6284 0, // small_common_section_flags
6285 elfcpp::SHF_X86_64_LARGE
, // large_common_section_flags
6286 NULL
, // attributes_section
6287 NULL
, // attributes_vendor
6288 "_start", // entry_symbol_name
6289 32, // hash_entry_size
6290 elfcpp::SHT_X86_64_UNWIND
, // unwind_section_type
6294 const Target::Target_info Target_x86_64_nacl
<32>::x86_64_nacl_info
=
6297 false, // is_big_endian
6298 elfcpp::EM_X86_64
, // machine_code
6299 false, // has_make_symbol
6300 false, // has_resolve
6301 true, // has_code_fill
6302 true, // is_default_stack_executable
6303 true, // can_icf_inline_merge_sections
6305 "/lib/ld-nacl-x86-64.so.1", // dynamic_linker
6306 0x20000, // default_text_segment_address
6307 0x10000, // abi_pagesize (overridable by -z max-page-size)
6308 0x10000, // common_pagesize (overridable by -z common-page-size)
6309 true, // isolate_execinstr
6310 0x10000000, // rosegment_gap
6311 elfcpp::SHN_UNDEF
, // small_common_shndx
6312 elfcpp::SHN_X86_64_LCOMMON
, // large_common_shndx
6313 0, // small_common_section_flags
6314 elfcpp::SHF_X86_64_LARGE
, // large_common_section_flags
6315 NULL
, // attributes_section
6316 NULL
, // attributes_vendor
6317 "_start", // entry_symbol_name
6318 32, // hash_entry_size
6319 elfcpp::SHT_X86_64_UNWIND
, // unwind_section_type
6322 #define NACLMASK 0xe0 // 32-byte alignment mask.
6324 // The first entry in the PLT.
6328 Output_data_plt_x86_64_nacl
<size
>::first_plt_entry
[plt_entry_size
] =
6330 0xff, 0x35, // pushq contents of memory address
6331 0, 0, 0, 0, // replaced with address of .got + 8
6332 0x4c, 0x8b, 0x1d, // mov GOT+16(%rip), %r11
6333 0, 0, 0, 0, // replaced with address of .got + 16
6334 0x41, 0x83, 0xe3, NACLMASK
, // and $-32, %r11d
6335 0x4d, 0x01, 0xfb, // add %r15, %r11
6336 0x41, 0xff, 0xe3, // jmpq *%r11
6338 // 9-byte nop sequence to pad out to the next 32-byte boundary.
6339 0x66, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw 0x0(%rax,%rax,1)
6341 // 32 bytes of nop to pad out to the standard size
6342 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, // excess data32 prefixes
6343 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
6344 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, // excess data32 prefixes
6345 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
6346 0x66, // excess data32 prefix
6352 Output_data_plt_x86_64_nacl
<size
>::do_fill_first_plt_entry(
6354 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
6355 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
)
6357 memcpy(pov
, first_plt_entry
, plt_entry_size
);
6358 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
6360 - (plt_address
+ 2 + 4)));
6361 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 9,
6363 - (plt_address
+ 9 + 4)));
6366 // Subsequent entries in the PLT.
6370 Output_data_plt_x86_64_nacl
<size
>::plt_entry
[plt_entry_size
] =
6372 0x4c, 0x8b, 0x1d, // mov name@GOTPCREL(%rip),%r11
6373 0, 0, 0, 0, // replaced with address of symbol in .got
6374 0x41, 0x83, 0xe3, NACLMASK
, // and $-32, %r11d
6375 0x4d, 0x01, 0xfb, // add %r15, %r11
6376 0x41, 0xff, 0xe3, // jmpq *%r11
6378 // 15-byte nop sequence to pad out to the next 32-byte boundary.
6379 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, // excess data32 prefixes
6380 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
6382 // Lazy GOT entries point here (32-byte aligned).
6383 0x68, // pushq immediate
6384 0, 0, 0, 0, // replaced with index into relocation table
6385 0xe9, // jmp relative
6386 0, 0, 0, 0, // replaced with offset to start of .plt0
6388 // 22 bytes of nop to pad out to the standard size.
6389 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, // excess data32 prefixes
6390 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
6391 0x0f, 0x1f, 0x80, 0, 0, 0, 0, // nopl 0x0(%rax)
6396 Output_data_plt_x86_64_nacl
<size
>::do_fill_plt_entry(
6398 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
6399 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
6400 unsigned int got_offset
,
6401 unsigned int plt_offset
,
6402 unsigned int plt_index
)
6404 memcpy(pov
, plt_entry
, plt_entry_size
);
6405 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 3,
6406 (got_address
+ got_offset
6407 - (plt_address
+ plt_offset
6410 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 33, plt_index
);
6411 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 38,
6412 - (plt_offset
+ 38 + 4));
6417 // The reserved TLSDESC entry in the PLT.
6421 Output_data_plt_x86_64_nacl
<size
>::tlsdesc_plt_entry
[plt_entry_size
] =
6423 0xff, 0x35, // pushq x(%rip)
6424 0, 0, 0, 0, // replaced with address of linkmap GOT entry (at PLTGOT + 8)
6425 0x4c, 0x8b, 0x1d, // mov y(%rip),%r11
6426 0, 0, 0, 0, // replaced with offset of reserved TLSDESC_GOT entry
6427 0x41, 0x83, 0xe3, NACLMASK
, // and $-32, %r11d
6428 0x4d, 0x01, 0xfb, // add %r15, %r11
6429 0x41, 0xff, 0xe3, // jmpq *%r11
6431 // 41 bytes of nop to pad out to the standard size.
6432 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, // excess data32 prefixes
6433 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
6434 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, // excess data32 prefixes
6435 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
6436 0x66, 0x66, // excess data32 prefixes
6437 0x2e, 0x0f, 0x1f, 0x84, 0, 0, 0, 0, 0, // nopw %cs:0x0(%rax,%rax,1)
6442 Output_data_plt_x86_64_nacl
<size
>::do_fill_tlsdesc_entry(
6444 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_address
,
6445 typename
elfcpp::Elf_types
<size
>::Elf_Addr plt_address
,
6446 typename
elfcpp::Elf_types
<size
>::Elf_Addr got_base
,
6447 unsigned int tlsdesc_got_offset
,
6448 unsigned int plt_offset
)
6450 memcpy(pov
, tlsdesc_plt_entry
, plt_entry_size
);
6451 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
6453 - (plt_address
+ plt_offset
6455 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 9,
6457 + tlsdesc_got_offset
6458 - (plt_address
+ plt_offset
6462 // The .eh_frame unwind information for the PLT.
6466 Output_data_plt_x86_64_nacl
<size
>::plt_eh_frame_fde
[plt_eh_frame_fde_size
] =
6468 0, 0, 0, 0, // Replaced with offset to .plt.
6469 0, 0, 0, 0, // Replaced with size of .plt.
6470 0, // Augmentation size.
6471 elfcpp::DW_CFA_def_cfa_offset
, 16, // DW_CFA_def_cfa_offset: 16.
6472 elfcpp::DW_CFA_advance_loc
+ 6, // Advance 6 to __PLT__ + 6.
6473 elfcpp::DW_CFA_def_cfa_offset
, 24, // DW_CFA_def_cfa_offset: 24.
6474 elfcpp::DW_CFA_advance_loc
+ 58, // Advance 58 to __PLT__ + 64.
6475 elfcpp::DW_CFA_def_cfa_expression
, // DW_CFA_def_cfa_expression.
6476 13, // Block length.
6477 elfcpp::DW_OP_breg7
, 8, // Push %rsp + 8.
6478 elfcpp::DW_OP_breg16
, 0, // Push %rip.
6479 elfcpp::DW_OP_const1u
, 63, // Push 0x3f.
6480 elfcpp::DW_OP_and
, // & (%rip & 0x3f).
6481 elfcpp::DW_OP_const1u
, 37, // Push 0x25.
6482 elfcpp::DW_OP_ge
, // >= ((%rip & 0x3f) >= 0x25)
6483 elfcpp::DW_OP_lit3
, // Push 3.
6484 elfcpp::DW_OP_shl
, // << (((%rip & 0x3f) >= 0x25) << 3)
6485 elfcpp::DW_OP_plus
, // + ((((%rip&0x3f)>=0x25)<<3)+%rsp+8
6486 elfcpp::DW_CFA_nop
, // Align to 32 bytes.
6490 // Return a string used to fill a code section with nops.
6491 // For NaCl, long NOPs are only valid if they do not cross
6492 // bundle alignment boundaries, so keep it simple with one-byte NOPs.
6495 Target_x86_64_nacl
<size
>::do_code_fill(section_size_type length
) const
6497 return std::string(length
, static_cast<char>(0x90));
6500 // The selector for x86_64-nacl object files.
6503 class Target_selector_x86_64_nacl
6504 : public Target_selector_nacl
<Target_selector_x86_64
<size
>,
6505 Target_x86_64_nacl
<size
> >
6508 Target_selector_x86_64_nacl()
6509 : Target_selector_nacl
<Target_selector_x86_64
<size
>,
6510 Target_x86_64_nacl
<size
> >("x86-64",
6512 ? "elf64-x86-64-nacl"
6513 : "elf32-x86-64-nacl",
6516 : "elf32_x86_64_nacl")
6520 Target_selector_x86_64_nacl
<64> target_selector_x86_64
;
6521 Target_selector_x86_64_nacl
<32> target_selector_x32
;
6523 } // End anonymous namespace.