1 // i386.cc -- i386 target support for gold.
3 // Copyright (C) 2006-2015 Free Software Foundation, Inc.
4 // Written by Ian Lance Taylor <iant@google.com>.
6 // This file is part of gold.
8 // This program is free software; you can redistribute it and/or modify
9 // it under the terms of the GNU General Public License as published by
10 // the Free Software Foundation; either version 3 of the License, or
11 // (at your option) any later version.
13 // This program is distributed in the hope that it will be useful,
14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 // GNU General Public License for more details.
18 // You should have received a copy of the GNU General Public License
19 // along with this program; if not, write to the Free Software
20 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
21 // MA 02110-1301, USA.
29 #include "parameters.h"
36 #include "copy-relocs.h"
38 #include "target-reloc.h"
39 #include "target-select.h"
50 // A class to handle the .got.plt section.
52 class Output_data_got_plt_i386
: public Output_section_data_build
55 Output_data_got_plt_i386(Layout
* layout
)
56 : Output_section_data_build(4),
61 // Write out the PLT data.
63 do_write(Output_file
*);
65 // Write to a map file.
67 do_print_to_mapfile(Mapfile
* mapfile
) const
68 { mapfile
->print_output_data(this, "** GOT PLT"); }
71 // A pointer to the Layout class, so that we can find the .dynamic
72 // section when we write out the GOT PLT section.
76 // A class to handle the PLT data.
77 // This is an abstract base class that handles most of the linker details
78 // but does not know the actual contents of PLT entries. The derived
79 // classes below fill in those details.
81 class Output_data_plt_i386
: public Output_section_data
84 typedef Output_data_reloc
<elfcpp::SHT_REL
, true, 32, false> Reloc_section
;
86 Output_data_plt_i386(Layout
*, uint64_t addralign
,
87 Output_data_got_plt_i386
*, Output_data_space
*);
89 // Add an entry to the PLT.
91 add_entry(Symbol_table
*, Layout
*, Symbol
* gsym
);
93 // Add an entry to the PLT for a local STT_GNU_IFUNC symbol.
95 add_local_ifunc_entry(Symbol_table
*, Layout
*,
96 Sized_relobj_file
<32, false>* relobj
,
97 unsigned int local_sym_index
);
99 // Return the .rel.plt section data.
102 { return this->rel_
; }
104 // Return where the TLS_DESC relocations should go.
106 rel_tls_desc(Layout
*);
108 // Return where the IRELATIVE relocations should go.
110 rel_irelative(Symbol_table
*, Layout
*);
112 // Return whether we created a section for IRELATIVE relocations.
114 has_irelative_section() const
115 { return this->irelative_rel_
!= NULL
; }
117 // Return the number of PLT entries.
120 { return this->count_
+ this->irelative_count_
; }
122 // Return the offset of the first non-reserved PLT entry.
124 first_plt_entry_offset()
125 { return this->get_plt_entry_size(); }
127 // Return the size of a PLT entry.
129 get_plt_entry_size() const
130 { return this->do_get_plt_entry_size(); }
132 // Return the PLT address to use for a global symbol.
134 address_for_global(const Symbol
*);
136 // Return the PLT address to use for a local symbol.
138 address_for_local(const Relobj
*, unsigned int symndx
);
140 // Add .eh_frame information for the PLT.
142 add_eh_frame(Layout
* layout
)
143 { this->do_add_eh_frame(layout
); }
146 // Fill the first PLT entry, given the pointer to the PLT section data
147 // and the runtime address of the GOT.
149 fill_first_plt_entry(unsigned char* pov
,
150 elfcpp::Elf_types
<32>::Elf_Addr got_address
)
151 { this->do_fill_first_plt_entry(pov
, got_address
); }
153 // Fill a normal PLT entry, given the pointer to the entry's data in the
154 // section, the runtime address of the GOT, the offset into the GOT of
155 // the corresponding slot, the offset into the relocation section of the
156 // corresponding reloc, and the offset of this entry within the whole
157 // PLT. Return the offset from this PLT entry's runtime address that
158 // should be used to compute the initial value of the GOT slot.
160 fill_plt_entry(unsigned char* pov
,
161 elfcpp::Elf_types
<32>::Elf_Addr got_address
,
162 unsigned int got_offset
,
163 unsigned int plt_offset
,
164 unsigned int plt_rel_offset
)
166 return this->do_fill_plt_entry(pov
, got_address
, got_offset
,
167 plt_offset
, plt_rel_offset
);
171 do_get_plt_entry_size() const = 0;
174 do_fill_first_plt_entry(unsigned char* pov
,
175 elfcpp::Elf_types
<32>::Elf_Addr got_address
) = 0;
178 do_fill_plt_entry(unsigned char* pov
,
179 elfcpp::Elf_types
<32>::Elf_Addr got_address
,
180 unsigned int got_offset
,
181 unsigned int plt_offset
,
182 unsigned int plt_rel_offset
) = 0;
185 do_add_eh_frame(Layout
*) = 0;
188 do_adjust_output_section(Output_section
* os
);
190 // Write to a map file.
192 do_print_to_mapfile(Mapfile
* mapfile
) const
193 { mapfile
->print_output_data(this, _("** PLT")); }
195 // The .eh_frame unwind information for the PLT.
196 // The CIE is common across variants of the PLT format.
197 static const int plt_eh_frame_cie_size
= 16;
198 static const unsigned char plt_eh_frame_cie
[plt_eh_frame_cie_size
];
201 // Set the final size.
203 set_final_data_size()
205 this->set_data_size((this->count_
+ this->irelative_count_
+ 1)
206 * this->get_plt_entry_size());
209 // Write out the PLT data.
211 do_write(Output_file
*);
213 // We keep a list of global STT_GNU_IFUNC symbols, each with its
214 // offset in the GOT.
218 unsigned int got_offset
;
221 // We keep a list of local STT_GNU_IFUNC symbols, each with its
222 // offset in the GOT.
225 Sized_relobj_file
<32, false>* object
;
226 unsigned int local_sym_index
;
227 unsigned int got_offset
;
230 // The reloc section.
232 // The TLS_DESC relocations, if necessary. These must follow the
233 // regular PLT relocs.
234 Reloc_section
* tls_desc_rel_
;
235 // The IRELATIVE relocations, if necessary. These must follow the
236 // regular relocatoins and the TLS_DESC relocations.
237 Reloc_section
* irelative_rel_
;
238 // The .got.plt section.
239 Output_data_got_plt_i386
* got_plt_
;
240 // The part of the .got.plt section used for IRELATIVE relocs.
241 Output_data_space
* got_irelative_
;
242 // The number of PLT entries.
244 // Number of PLT entries with R_386_IRELATIVE relocs. These follow
245 // the regular PLT entries.
246 unsigned int irelative_count_
;
247 // Global STT_GNU_IFUNC symbols.
248 std::vector
<Global_ifunc
> global_ifuncs_
;
249 // Local STT_GNU_IFUNC symbols.
250 std::vector
<Local_ifunc
> local_ifuncs_
;
253 // This is an abstract class for the standard PLT layout.
254 // The derived classes below handle the actual PLT contents
255 // for the executable (non-PIC) and shared-library (PIC) cases.
256 // The unwind information is uniform across those two, so it's here.
258 class Output_data_plt_i386_standard
: public Output_data_plt_i386
261 Output_data_plt_i386_standard(Layout
* layout
,
262 Output_data_got_plt_i386
* got_plt
,
263 Output_data_space
* got_irelative
)
264 : Output_data_plt_i386(layout
, plt_entry_size
, got_plt
, got_irelative
)
269 do_get_plt_entry_size() const
270 { return plt_entry_size
; }
273 do_add_eh_frame(Layout
* layout
)
275 layout
->add_eh_frame_for_plt(this, plt_eh_frame_cie
, plt_eh_frame_cie_size
,
276 plt_eh_frame_fde
, plt_eh_frame_fde_size
);
279 // The size of an entry in the PLT.
280 static const int plt_entry_size
= 16;
282 // The .eh_frame unwind information for the PLT.
283 static const int plt_eh_frame_fde_size
= 32;
284 static const unsigned char plt_eh_frame_fde
[plt_eh_frame_fde_size
];
287 // Actually fill the PLT contents for an executable (non-PIC).
289 class Output_data_plt_i386_exec
: public Output_data_plt_i386_standard
292 Output_data_plt_i386_exec(Layout
* layout
,
293 Output_data_got_plt_i386
* got_plt
,
294 Output_data_space
* got_irelative
)
295 : Output_data_plt_i386_standard(layout
, got_plt
, got_irelative
)
300 do_fill_first_plt_entry(unsigned char* pov
,
301 elfcpp::Elf_types
<32>::Elf_Addr got_address
);
304 do_fill_plt_entry(unsigned char* pov
,
305 elfcpp::Elf_types
<32>::Elf_Addr got_address
,
306 unsigned int got_offset
,
307 unsigned int plt_offset
,
308 unsigned int plt_rel_offset
);
311 // The first entry in the PLT for an executable.
312 static const unsigned char first_plt_entry
[plt_entry_size
];
314 // Other entries in the PLT for an executable.
315 static const unsigned char plt_entry
[plt_entry_size
];
318 // Actually fill the PLT contents for a shared library (PIC).
320 class Output_data_plt_i386_dyn
: public Output_data_plt_i386_standard
323 Output_data_plt_i386_dyn(Layout
* layout
,
324 Output_data_got_plt_i386
* got_plt
,
325 Output_data_space
* got_irelative
)
326 : Output_data_plt_i386_standard(layout
, got_plt
, got_irelative
)
331 do_fill_first_plt_entry(unsigned char* pov
, elfcpp::Elf_types
<32>::Elf_Addr
);
334 do_fill_plt_entry(unsigned char* pov
,
335 elfcpp::Elf_types
<32>::Elf_Addr
,
336 unsigned int got_offset
,
337 unsigned int plt_offset
,
338 unsigned int plt_rel_offset
);
341 // The first entry in the PLT for a shared object.
342 static const unsigned char first_plt_entry
[plt_entry_size
];
344 // Other entries in the PLT for a shared object.
345 static const unsigned char plt_entry
[plt_entry_size
];
348 // The i386 target class.
349 // TLS info comes from
350 // http://people.redhat.com/drepper/tls.pdf
351 // http://www.lsd.ic.unicamp.br/~oliva/writeups/TLS/RFC-TLSDESC-x86.txt
353 class Target_i386
: public Sized_target
<32, false>
356 typedef Output_data_reloc
<elfcpp::SHT_REL
, true, 32, false> Reloc_section
;
358 Target_i386(const Target::Target_info
* info
= &i386_info
)
359 : Sized_target
<32, false>(info
),
360 got_(NULL
), plt_(NULL
), got_plt_(NULL
), got_irelative_(NULL
),
361 got_tlsdesc_(NULL
), global_offset_table_(NULL
), rel_dyn_(NULL
),
362 rel_irelative_(NULL
), copy_relocs_(elfcpp::R_386_COPY
),
363 got_mod_index_offset_(-1U), tls_base_symbol_defined_(false)
366 // Process the relocations to determine unreferenced sections for
367 // garbage collection.
369 gc_process_relocs(Symbol_table
* symtab
,
371 Sized_relobj_file
<32, false>* object
,
372 unsigned int data_shndx
,
373 unsigned int sh_type
,
374 const unsigned char* prelocs
,
376 Output_section
* output_section
,
377 bool needs_special_offset_handling
,
378 size_t local_symbol_count
,
379 const unsigned char* plocal_symbols
);
381 // Scan the relocations to look for symbol adjustments.
383 scan_relocs(Symbol_table
* symtab
,
385 Sized_relobj_file
<32, false>* object
,
386 unsigned int data_shndx
,
387 unsigned int sh_type
,
388 const unsigned char* prelocs
,
390 Output_section
* output_section
,
391 bool needs_special_offset_handling
,
392 size_t local_symbol_count
,
393 const unsigned char* plocal_symbols
);
395 // Finalize the sections.
397 do_finalize_sections(Layout
*, const Input_objects
*, Symbol_table
*);
399 // Return the value to use for a dynamic which requires special
402 do_dynsym_value(const Symbol
*) const;
404 // Relocate a section.
406 relocate_section(const Relocate_info
<32, false>*,
407 unsigned int sh_type
,
408 const unsigned char* prelocs
,
410 Output_section
* output_section
,
411 bool needs_special_offset_handling
,
413 elfcpp::Elf_types
<32>::Elf_Addr view_address
,
414 section_size_type view_size
,
415 const Reloc_symbol_changes
*);
417 // Scan the relocs during a relocatable link.
419 scan_relocatable_relocs(Symbol_table
* symtab
,
421 Sized_relobj_file
<32, false>* object
,
422 unsigned int data_shndx
,
423 unsigned int sh_type
,
424 const unsigned char* prelocs
,
426 Output_section
* output_section
,
427 bool needs_special_offset_handling
,
428 size_t local_symbol_count
,
429 const unsigned char* plocal_symbols
,
430 Relocatable_relocs
*);
432 // Emit relocations for a section.
434 relocate_relocs(const Relocate_info
<32, false>*,
435 unsigned int sh_type
,
436 const unsigned char* prelocs
,
438 Output_section
* output_section
,
439 elfcpp::Elf_types
<32>::Elf_Off offset_in_output_section
,
441 elfcpp::Elf_types
<32>::Elf_Addr view_address
,
442 section_size_type view_size
,
443 unsigned char* reloc_view
,
444 section_size_type reloc_view_size
);
446 // Return a string used to fill a code section with nops.
448 do_code_fill(section_size_type length
) const;
450 // Return whether SYM is defined by the ABI.
452 do_is_defined_by_abi(const Symbol
* sym
) const
453 { return strcmp(sym
->name(), "___tls_get_addr") == 0; }
455 // Return whether a symbol name implies a local label. The UnixWare
456 // 2.1 cc generates temporary symbols that start with .X, so we
457 // recognize them here. FIXME: do other SVR4 compilers also use .X?.
458 // If so, we should move the .X recognition into
459 // Target::do_is_local_label_name.
461 do_is_local_label_name(const char* name
) const
463 if (name
[0] == '.' && name
[1] == 'X')
465 return Target::do_is_local_label_name(name
);
468 // Return the PLT address to use for a global symbol.
470 do_plt_address_for_global(const Symbol
* gsym
) const
471 { return this->plt_section()->address_for_global(gsym
); }
474 do_plt_address_for_local(const Relobj
* relobj
, unsigned int symndx
) const
475 { return this->plt_section()->address_for_local(relobj
, symndx
); }
477 // We can tell whether we take the address of a function.
479 do_can_check_for_function_pointers() const
482 // Return the base for a DW_EH_PE_datarel encoding.
484 do_ehframe_datarel_base() const;
486 // Return whether SYM is call to a non-split function.
488 do_is_call_to_non_split(const Symbol
* sym
, unsigned int) const;
490 // Adjust -fsplit-stack code which calls non-split-stack code.
492 do_calls_non_split(Relobj
* object
, unsigned int shndx
,
493 section_offset_type fnoffset
, section_size_type fnsize
,
494 unsigned char* view
, section_size_type view_size
,
495 std::string
* from
, std::string
* to
) const;
497 // Return the size of the GOT section.
501 gold_assert(this->got_
!= NULL
);
502 return this->got_
->data_size();
505 // Return the number of entries in the GOT.
507 got_entry_count() const
509 if (this->got_
== NULL
)
511 return this->got_size() / 4;
514 // Return the number of entries in the PLT.
516 plt_entry_count() const;
518 // Return the offset of the first non-reserved PLT entry.
520 first_plt_entry_offset() const;
522 // Return the size of each PLT entry.
524 plt_entry_size() const;
527 // Instantiate the plt_ member.
528 // This chooses the right PLT flavor for an executable or a shared object.
529 Output_data_plt_i386
*
530 make_data_plt(Layout
* layout
,
531 Output_data_got_plt_i386
* got_plt
,
532 Output_data_space
* got_irelative
,
534 { return this->do_make_data_plt(layout
, got_plt
, got_irelative
, dyn
); }
536 virtual Output_data_plt_i386
*
537 do_make_data_plt(Layout
* layout
,
538 Output_data_got_plt_i386
* got_plt
,
539 Output_data_space
* got_irelative
,
543 return new Output_data_plt_i386_dyn(layout
, got_plt
, got_irelative
);
545 return new Output_data_plt_i386_exec(layout
, got_plt
, got_irelative
);
549 // The class which scans relocations.
554 get_reference_flags(unsigned int r_type
);
557 local(Symbol_table
* symtab
, Layout
* layout
, Target_i386
* target
,
558 Sized_relobj_file
<32, false>* object
,
559 unsigned int data_shndx
,
560 Output_section
* output_section
,
561 const elfcpp::Rel
<32, false>& reloc
, unsigned int r_type
,
562 const elfcpp::Sym
<32, false>& lsym
,
566 global(Symbol_table
* symtab
, Layout
* layout
, Target_i386
* target
,
567 Sized_relobj_file
<32, false>* object
,
568 unsigned int data_shndx
,
569 Output_section
* output_section
,
570 const elfcpp::Rel
<32, false>& reloc
, unsigned int r_type
,
574 local_reloc_may_be_function_pointer(Symbol_table
* symtab
, Layout
* layout
,
576 Sized_relobj_file
<32, false>* object
,
577 unsigned int data_shndx
,
578 Output_section
* output_section
,
579 const elfcpp::Rel
<32, false>& reloc
,
581 const elfcpp::Sym
<32, false>& lsym
);
584 global_reloc_may_be_function_pointer(Symbol_table
* symtab
, Layout
* layout
,
586 Sized_relobj_file
<32, false>* object
,
587 unsigned int data_shndx
,
588 Output_section
* output_section
,
589 const elfcpp::Rel
<32, false>& reloc
,
594 possible_function_pointer_reloc(unsigned int r_type
);
597 reloc_needs_plt_for_ifunc(Sized_relobj_file
<32, false>*,
598 unsigned int r_type
);
601 unsupported_reloc_local(Sized_relobj_file
<32, false>*, unsigned int r_type
);
604 unsupported_reloc_global(Sized_relobj_file
<32, false>*, unsigned int r_type
,
608 // The class which implements relocation.
613 : skip_call_tls_get_addr_(false),
614 local_dynamic_type_(LOCAL_DYNAMIC_NONE
)
619 if (this->skip_call_tls_get_addr_
)
621 // FIXME: This needs to specify the location somehow.
622 gold_error(_("missing expected TLS relocation"));
626 // Return whether the static relocation needs to be applied.
628 should_apply_static_reloc(const Sized_symbol
<32>* gsym
,
631 Output_section
* output_section
);
633 // Do a relocation. Return false if the caller should not issue
634 // any warnings about this relocation.
636 relocate(const Relocate_info
<32, false>*, unsigned int,
637 Target_i386
*, Output_section
*, size_t, const unsigned char*,
638 const Sized_symbol
<32>*, const Symbol_value
<32>*,
639 unsigned char*, elfcpp::Elf_types
<32>::Elf_Addr
,
643 // Do a TLS relocation.
645 relocate_tls(const Relocate_info
<32, false>*, Target_i386
* target
,
646 size_t relnum
, const elfcpp::Rel
<32, false>&,
647 unsigned int r_type
, const Sized_symbol
<32>*,
648 const Symbol_value
<32>*,
649 unsigned char*, elfcpp::Elf_types
<32>::Elf_Addr
,
652 // Do a TLS General-Dynamic to Initial-Exec transition.
654 tls_gd_to_ie(const Relocate_info
<32, false>*, size_t relnum
,
655 Output_segment
* tls_segment
,
656 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
657 elfcpp::Elf_types
<32>::Elf_Addr value
,
659 section_size_type view_size
);
661 // Do a TLS General-Dynamic to Local-Exec transition.
663 tls_gd_to_le(const Relocate_info
<32, false>*, size_t relnum
,
664 Output_segment
* tls_segment
,
665 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
666 elfcpp::Elf_types
<32>::Elf_Addr value
,
668 section_size_type view_size
);
670 // Do a TLS_GOTDESC or TLS_DESC_CALL General-Dynamic to Initial-Exec
673 tls_desc_gd_to_ie(const Relocate_info
<32, false>*, size_t relnum
,
674 Output_segment
* tls_segment
,
675 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
676 elfcpp::Elf_types
<32>::Elf_Addr value
,
678 section_size_type view_size
);
680 // Do a TLS_GOTDESC or TLS_DESC_CALL General-Dynamic to Local-Exec
683 tls_desc_gd_to_le(const Relocate_info
<32, false>*, size_t relnum
,
684 Output_segment
* tls_segment
,
685 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
686 elfcpp::Elf_types
<32>::Elf_Addr value
,
688 section_size_type view_size
);
690 // Do a TLS Local-Dynamic to Local-Exec transition.
692 tls_ld_to_le(const Relocate_info
<32, false>*, size_t relnum
,
693 Output_segment
* tls_segment
,
694 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
695 elfcpp::Elf_types
<32>::Elf_Addr value
,
697 section_size_type view_size
);
699 // Do a TLS Initial-Exec to Local-Exec transition.
701 tls_ie_to_le(const Relocate_info
<32, false>*, size_t relnum
,
702 Output_segment
* tls_segment
,
703 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
704 elfcpp::Elf_types
<32>::Elf_Addr value
,
706 section_size_type view_size
);
708 // We need to keep track of which type of local dynamic relocation
709 // we have seen, so that we can optimize R_386_TLS_LDO_32 correctly.
710 enum Local_dynamic_type
717 // This is set if we should skip the next reloc, which should be a
718 // PLT32 reloc against ___tls_get_addr.
719 bool skip_call_tls_get_addr_
;
720 // The type of local dynamic relocation we have seen in the section
721 // being relocated, if any.
722 Local_dynamic_type local_dynamic_type_
;
725 // A class which returns the size required for a relocation type,
726 // used while scanning relocs during a relocatable link.
727 class Relocatable_size_for_reloc
731 get_size_for_reloc(unsigned int, Relobj
*);
734 // Adjust TLS relocation type based on the options and whether this
735 // is a local symbol.
736 static tls::Tls_optimization
737 optimize_tls_reloc(bool is_final
, int r_type
);
739 // Check if relocation against this symbol is a candidate for
741 // mov foo@GOT(%reg), %reg
743 // lea foo@GOTOFF(%reg), %reg.
745 can_convert_mov_to_lea(const Symbol
* gsym
)
747 gold_assert(gsym
!= NULL
);
748 return (gsym
->type() != elfcpp::STT_GNU_IFUNC
749 && !gsym
->is_undefined ()
750 && !gsym
->is_from_dynobj()
751 && !gsym
->is_preemptible()
752 && (!parameters
->options().shared()
753 || (gsym
->visibility() != elfcpp::STV_DEFAULT
754 && gsym
->visibility() != elfcpp::STV_PROTECTED
)
755 || parameters
->options().Bsymbolic())
756 && strcmp(gsym
->name(), "_DYNAMIC") != 0);
759 // Get the GOT section, creating it if necessary.
760 Output_data_got
<32, false>*
761 got_section(Symbol_table
*, Layout
*);
763 // Get the GOT PLT section.
764 Output_data_got_plt_i386
*
765 got_plt_section() const
767 gold_assert(this->got_plt_
!= NULL
);
768 return this->got_plt_
;
771 // Get the GOT section for TLSDESC entries.
772 Output_data_got
<32, false>*
773 got_tlsdesc_section() const
775 gold_assert(this->got_tlsdesc_
!= NULL
);
776 return this->got_tlsdesc_
;
779 // Create the PLT section.
781 make_plt_section(Symbol_table
* symtab
, Layout
* layout
);
783 // Create a PLT entry for a global symbol.
785 make_plt_entry(Symbol_table
*, Layout
*, Symbol
*);
787 // Create a PLT entry for a local STT_GNU_IFUNC symbol.
789 make_local_ifunc_plt_entry(Symbol_table
*, Layout
*,
790 Sized_relobj_file
<32, false>* relobj
,
791 unsigned int local_sym_index
);
793 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
795 define_tls_base_symbol(Symbol_table
*, Layout
*);
797 // Create a GOT entry for the TLS module index.
799 got_mod_index_entry(Symbol_table
* symtab
, Layout
* layout
,
800 Sized_relobj_file
<32, false>* object
);
802 // Get the PLT section.
803 Output_data_plt_i386
*
806 gold_assert(this->plt_
!= NULL
);
810 // Get the dynamic reloc section, creating it if necessary.
812 rel_dyn_section(Layout
*);
814 // Get the section to use for TLS_DESC relocations.
816 rel_tls_desc_section(Layout
*) const;
818 // Get the section to use for IRELATIVE relocations.
820 rel_irelative_section(Layout
*);
822 // Add a potential copy relocation.
824 copy_reloc(Symbol_table
* symtab
, Layout
* layout
,
825 Sized_relobj_file
<32, false>* object
,
826 unsigned int shndx
, Output_section
* output_section
,
827 Symbol
* sym
, const elfcpp::Rel
<32, false>& reloc
)
829 unsigned int r_type
= elfcpp::elf_r_type
<32>(reloc
.get_r_info());
830 this->copy_relocs_
.copy_reloc(symtab
, layout
,
831 symtab
->get_sized_symbol
<32>(sym
),
832 object
, shndx
, output_section
,
833 r_type
, reloc
.get_r_offset(), 0,
834 this->rel_dyn_section(layout
));
837 // Information about this specific target which we pass to the
838 // general Target structure.
839 static const Target::Target_info i386_info
;
841 // The types of GOT entries needed for this platform.
842 // These values are exposed to the ABI in an incremental link.
843 // Do not renumber existing values without changing the version
844 // number of the .gnu_incremental_inputs section.
847 GOT_TYPE_STANDARD
= 0, // GOT entry for a regular symbol
848 GOT_TYPE_TLS_NOFFSET
= 1, // GOT entry for negative TLS offset
849 GOT_TYPE_TLS_OFFSET
= 2, // GOT entry for positive TLS offset
850 GOT_TYPE_TLS_PAIR
= 3, // GOT entry for TLS module/offset pair
851 GOT_TYPE_TLS_DESC
= 4 // GOT entry for TLS_DESC pair
855 Output_data_got
<32, false>* got_
;
857 Output_data_plt_i386
* plt_
;
858 // The GOT PLT section.
859 Output_data_got_plt_i386
* got_plt_
;
860 // The GOT section for IRELATIVE relocations.
861 Output_data_space
* got_irelative_
;
862 // The GOT section for TLSDESC relocations.
863 Output_data_got
<32, false>* got_tlsdesc_
;
864 // The _GLOBAL_OFFSET_TABLE_ symbol.
865 Symbol
* global_offset_table_
;
866 // The dynamic reloc section.
867 Reloc_section
* rel_dyn_
;
868 // The section to use for IRELATIVE relocs.
869 Reloc_section
* rel_irelative_
;
870 // Relocs saved to avoid a COPY reloc.
871 Copy_relocs
<elfcpp::SHT_REL
, 32, false> copy_relocs_
;
872 // Offset of the GOT entry for the TLS module index.
873 unsigned int got_mod_index_offset_
;
874 // True if the _TLS_MODULE_BASE_ symbol has been defined.
875 bool tls_base_symbol_defined_
;
878 const Target::Target_info
Target_i386::i386_info
=
881 false, // is_big_endian
882 elfcpp::EM_386
, // machine_code
883 false, // has_make_symbol
884 false, // has_resolve
885 true, // has_code_fill
886 true, // is_default_stack_executable
887 true, // can_icf_inline_merge_sections
889 "/usr/lib/libc.so.1", // dynamic_linker
890 0x08048000, // default_text_segment_address
891 0x1000, // abi_pagesize (overridable by -z max-page-size)
892 0x1000, // common_pagesize (overridable by -z common-page-size)
893 false, // isolate_execinstr
895 elfcpp::SHN_UNDEF
, // small_common_shndx
896 elfcpp::SHN_UNDEF
, // large_common_shndx
897 0, // small_common_section_flags
898 0, // large_common_section_flags
899 NULL
, // attributes_section
900 NULL
, // attributes_vendor
901 "_start", // entry_symbol_name
902 32, // hash_entry_size
905 // Get the GOT section, creating it if necessary.
907 Output_data_got
<32, false>*
908 Target_i386::got_section(Symbol_table
* symtab
, Layout
* layout
)
910 if (this->got_
== NULL
)
912 gold_assert(symtab
!= NULL
&& layout
!= NULL
);
914 this->got_
= new Output_data_got
<32, false>();
916 // When using -z now, we can treat .got.plt as a relro section.
917 // Without -z now, it is modified after program startup by lazy
919 bool is_got_plt_relro
= parameters
->options().now();
920 Output_section_order got_order
= (is_got_plt_relro
923 Output_section_order got_plt_order
= (is_got_plt_relro
925 : ORDER_NON_RELRO_FIRST
);
927 layout
->add_output_section_data(".got", elfcpp::SHT_PROGBITS
,
929 | elfcpp::SHF_WRITE
),
930 this->got_
, got_order
, true);
932 this->got_plt_
= new Output_data_got_plt_i386(layout
);
933 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
935 | elfcpp::SHF_WRITE
),
936 this->got_plt_
, got_plt_order
,
939 // The first three entries are reserved.
940 this->got_plt_
->set_current_data_size(3 * 4);
942 if (!is_got_plt_relro
)
944 // Those bytes can go into the relro segment.
945 layout
->increase_relro(3 * 4);
948 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
949 this->global_offset_table_
=
950 symtab
->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL
,
951 Symbol_table::PREDEFINED
,
953 0, 0, elfcpp::STT_OBJECT
,
955 elfcpp::STV_HIDDEN
, 0,
958 // If there are any IRELATIVE relocations, they get GOT entries
959 // in .got.plt after the jump slot relocations.
960 this->got_irelative_
= new Output_data_space(4, "** GOT IRELATIVE PLT");
961 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
963 | elfcpp::SHF_WRITE
),
964 this->got_irelative_
,
965 got_plt_order
, is_got_plt_relro
);
967 // If there are any TLSDESC relocations, they get GOT entries in
968 // .got.plt after the jump slot entries.
969 this->got_tlsdesc_
= new Output_data_got
<32, false>();
970 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
972 | elfcpp::SHF_WRITE
),
974 got_plt_order
, is_got_plt_relro
);
980 // Get the dynamic reloc section, creating it if necessary.
982 Target_i386::Reloc_section
*
983 Target_i386::rel_dyn_section(Layout
* layout
)
985 if (this->rel_dyn_
== NULL
)
987 gold_assert(layout
!= NULL
);
988 this->rel_dyn_
= new Reloc_section(parameters
->options().combreloc());
989 layout
->add_output_section_data(".rel.dyn", elfcpp::SHT_REL
,
990 elfcpp::SHF_ALLOC
, this->rel_dyn_
,
991 ORDER_DYNAMIC_RELOCS
, false);
993 return this->rel_dyn_
;
996 // Get the section to use for IRELATIVE relocs, creating it if
997 // necessary. These go in .rel.dyn, but only after all other dynamic
998 // relocations. They need to follow the other dynamic relocations so
999 // that they can refer to global variables initialized by those
1002 Target_i386::Reloc_section
*
1003 Target_i386::rel_irelative_section(Layout
* layout
)
1005 if (this->rel_irelative_
== NULL
)
1007 // Make sure we have already create the dynamic reloc section.
1008 this->rel_dyn_section(layout
);
1009 this->rel_irelative_
= new Reloc_section(false);
1010 layout
->add_output_section_data(".rel.dyn", elfcpp::SHT_REL
,
1011 elfcpp::SHF_ALLOC
, this->rel_irelative_
,
1012 ORDER_DYNAMIC_RELOCS
, false);
1013 gold_assert(this->rel_dyn_
->output_section()
1014 == this->rel_irelative_
->output_section());
1016 return this->rel_irelative_
;
1019 // Write the first three reserved words of the .got.plt section.
1020 // The remainder of the section is written while writing the PLT
1021 // in Output_data_plt_i386::do_write.
1024 Output_data_got_plt_i386::do_write(Output_file
* of
)
1026 // The first entry in the GOT is the address of the .dynamic section
1027 // aka the PT_DYNAMIC segment. The next two entries are reserved.
1028 // We saved space for them when we created the section in
1029 // Target_i386::got_section.
1030 const off_t got_file_offset
= this->offset();
1031 gold_assert(this->data_size() >= 12);
1032 unsigned char* const got_view
= of
->get_output_view(got_file_offset
, 12);
1033 Output_section
* dynamic
= this->layout_
->dynamic_section();
1034 uint32_t dynamic_addr
= dynamic
== NULL
? 0 : dynamic
->address();
1035 elfcpp::Swap
<32, false>::writeval(got_view
, dynamic_addr
);
1036 memset(got_view
+ 4, 0, 8);
1037 of
->write_output_view(got_file_offset
, 12, got_view
);
1040 // Create the PLT section. The ordinary .got section is an argument,
1041 // since we need to refer to the start. We also create our own .got
1042 // section just for PLT entries.
1044 Output_data_plt_i386::Output_data_plt_i386(Layout
* layout
,
1046 Output_data_got_plt_i386
* got_plt
,
1047 Output_data_space
* got_irelative
)
1048 : Output_section_data(addralign
),
1049 tls_desc_rel_(NULL
), irelative_rel_(NULL
), got_plt_(got_plt
),
1050 got_irelative_(got_irelative
), count_(0), irelative_count_(0),
1051 global_ifuncs_(), local_ifuncs_()
1053 this->rel_
= new Reloc_section(false);
1054 layout
->add_output_section_data(".rel.plt", elfcpp::SHT_REL
,
1055 elfcpp::SHF_ALLOC
, this->rel_
,
1056 ORDER_DYNAMIC_PLT_RELOCS
, false);
1060 Output_data_plt_i386::do_adjust_output_section(Output_section
* os
)
1062 // UnixWare sets the entsize of .plt to 4, and so does the old GNU
1063 // linker, and so do we.
1067 // Add an entry to the PLT.
1070 Output_data_plt_i386::add_entry(Symbol_table
* symtab
, Layout
* layout
,
1073 gold_assert(!gsym
->has_plt_offset());
1075 // Every PLT entry needs a reloc.
1076 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
1077 && gsym
->can_use_relative_reloc(false))
1079 gsym
->set_plt_offset(this->irelative_count_
* this->get_plt_entry_size());
1080 ++this->irelative_count_
;
1081 section_offset_type got_offset
=
1082 this->got_irelative_
->current_data_size();
1083 this->got_irelative_
->set_current_data_size(got_offset
+ 4);
1084 Reloc_section
* rel
= this->rel_irelative(symtab
, layout
);
1085 rel
->add_symbolless_global_addend(gsym
, elfcpp::R_386_IRELATIVE
,
1086 this->got_irelative_
, got_offset
);
1087 struct Global_ifunc gi
;
1089 gi
.got_offset
= got_offset
;
1090 this->global_ifuncs_
.push_back(gi
);
1094 // When setting the PLT offset we skip the initial reserved PLT
1096 gsym
->set_plt_offset((this->count_
+ 1) * this->get_plt_entry_size());
1100 section_offset_type got_offset
= this->got_plt_
->current_data_size();
1102 // Every PLT entry needs a GOT entry which points back to the
1103 // PLT entry (this will be changed by the dynamic linker,
1104 // normally lazily when the function is called).
1105 this->got_plt_
->set_current_data_size(got_offset
+ 4);
1107 gsym
->set_needs_dynsym_entry();
1108 this->rel_
->add_global(gsym
, elfcpp::R_386_JUMP_SLOT
, this->got_plt_
,
1112 // Note that we don't need to save the symbol. The contents of the
1113 // PLT are independent of which symbols are used. The symbols only
1114 // appear in the relocations.
1117 // Add an entry to the PLT for a local STT_GNU_IFUNC symbol. Return
1121 Output_data_plt_i386::add_local_ifunc_entry(
1122 Symbol_table
* symtab
,
1124 Sized_relobj_file
<32, false>* relobj
,
1125 unsigned int local_sym_index
)
1127 unsigned int plt_offset
= this->irelative_count_
* this->get_plt_entry_size();
1128 ++this->irelative_count_
;
1130 section_offset_type got_offset
= this->got_irelative_
->current_data_size();
1132 // Every PLT entry needs a GOT entry which points back to the PLT
1134 this->got_irelative_
->set_current_data_size(got_offset
+ 4);
1136 // Every PLT entry needs a reloc.
1137 Reloc_section
* rel
= this->rel_irelative(symtab
, layout
);
1138 rel
->add_symbolless_local_addend(relobj
, local_sym_index
,
1139 elfcpp::R_386_IRELATIVE
,
1140 this->got_irelative_
, got_offset
);
1142 struct Local_ifunc li
;
1144 li
.local_sym_index
= local_sym_index
;
1145 li
.got_offset
= got_offset
;
1146 this->local_ifuncs_
.push_back(li
);
1151 // Return where the TLS_DESC relocations should go, creating it if
1152 // necessary. These follow the JUMP_SLOT relocations.
1154 Output_data_plt_i386::Reloc_section
*
1155 Output_data_plt_i386::rel_tls_desc(Layout
* layout
)
1157 if (this->tls_desc_rel_
== NULL
)
1159 this->tls_desc_rel_
= new Reloc_section(false);
1160 layout
->add_output_section_data(".rel.plt", elfcpp::SHT_REL
,
1161 elfcpp::SHF_ALLOC
, this->tls_desc_rel_
,
1162 ORDER_DYNAMIC_PLT_RELOCS
, false);
1163 gold_assert(this->tls_desc_rel_
->output_section()
1164 == this->rel_
->output_section());
1166 return this->tls_desc_rel_
;
1169 // Return where the IRELATIVE relocations should go in the PLT. These
1170 // follow the JUMP_SLOT and TLS_DESC relocations.
1172 Output_data_plt_i386::Reloc_section
*
1173 Output_data_plt_i386::rel_irelative(Symbol_table
* symtab
, Layout
* layout
)
1175 if (this->irelative_rel_
== NULL
)
1177 // Make sure we have a place for the TLS_DESC relocations, in
1178 // case we see any later on.
1179 this->rel_tls_desc(layout
);
1180 this->irelative_rel_
= new Reloc_section(false);
1181 layout
->add_output_section_data(".rel.plt", elfcpp::SHT_REL
,
1182 elfcpp::SHF_ALLOC
, this->irelative_rel_
,
1183 ORDER_DYNAMIC_PLT_RELOCS
, false);
1184 gold_assert(this->irelative_rel_
->output_section()
1185 == this->rel_
->output_section());
1187 if (parameters
->doing_static_link())
1189 // A statically linked executable will only have a .rel.plt
1190 // section to hold R_386_IRELATIVE relocs for STT_GNU_IFUNC
1191 // symbols. The library will use these symbols to locate
1192 // the IRELATIVE relocs at program startup time.
1193 symtab
->define_in_output_data("__rel_iplt_start", NULL
,
1194 Symbol_table::PREDEFINED
,
1195 this->irelative_rel_
, 0, 0,
1196 elfcpp::STT_NOTYPE
, elfcpp::STB_GLOBAL
,
1197 elfcpp::STV_HIDDEN
, 0, false, true);
1198 symtab
->define_in_output_data("__rel_iplt_end", NULL
,
1199 Symbol_table::PREDEFINED
,
1200 this->irelative_rel_
, 0, 0,
1201 elfcpp::STT_NOTYPE
, elfcpp::STB_GLOBAL
,
1202 elfcpp::STV_HIDDEN
, 0, true, true);
1205 return this->irelative_rel_
;
1208 // Return the PLT address to use for a global symbol.
1211 Output_data_plt_i386::address_for_global(const Symbol
* gsym
)
1213 uint64_t offset
= 0;
1214 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
1215 && gsym
->can_use_relative_reloc(false))
1216 offset
= (this->count_
+ 1) * this->get_plt_entry_size();
1217 return this->address() + offset
+ gsym
->plt_offset();
1220 // Return the PLT address to use for a local symbol. These are always
1221 // IRELATIVE relocs.
1224 Output_data_plt_i386::address_for_local(const Relobj
* object
,
1227 return (this->address()
1228 + (this->count_
+ 1) * this->get_plt_entry_size()
1229 + object
->local_plt_offset(r_sym
));
1232 // The first entry in the PLT for an executable.
1234 const unsigned char Output_data_plt_i386_exec::first_plt_entry
[plt_entry_size
] =
1236 0xff, 0x35, // pushl contents of memory address
1237 0, 0, 0, 0, // replaced with address of .got + 4
1238 0xff, 0x25, // jmp indirect
1239 0, 0, 0, 0, // replaced with address of .got + 8
1240 0, 0, 0, 0 // unused
1244 Output_data_plt_i386_exec::do_fill_first_plt_entry(
1246 elfcpp::Elf_types
<32>::Elf_Addr got_address
)
1248 memcpy(pov
, first_plt_entry
, plt_entry_size
);
1249 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2, got_address
+ 4);
1250 elfcpp::Swap
<32, false>::writeval(pov
+ 8, got_address
+ 8);
1253 // The first entry in the PLT for a shared object.
1255 const unsigned char Output_data_plt_i386_dyn::first_plt_entry
[plt_entry_size
] =
1257 0xff, 0xb3, 4, 0, 0, 0, // pushl 4(%ebx)
1258 0xff, 0xa3, 8, 0, 0, 0, // jmp *8(%ebx)
1259 0, 0, 0, 0 // unused
1263 Output_data_plt_i386_dyn::do_fill_first_plt_entry(
1265 elfcpp::Elf_types
<32>::Elf_Addr
)
1267 memcpy(pov
, first_plt_entry
, plt_entry_size
);
1270 // Subsequent entries in the PLT for an executable.
1272 const unsigned char Output_data_plt_i386_exec::plt_entry
[plt_entry_size
] =
1274 0xff, 0x25, // jmp indirect
1275 0, 0, 0, 0, // replaced with address of symbol in .got
1276 0x68, // pushl immediate
1277 0, 0, 0, 0, // replaced with offset into relocation table
1278 0xe9, // jmp relative
1279 0, 0, 0, 0 // replaced with offset to start of .plt
1283 Output_data_plt_i386_exec::do_fill_plt_entry(
1285 elfcpp::Elf_types
<32>::Elf_Addr got_address
,
1286 unsigned int got_offset
,
1287 unsigned int plt_offset
,
1288 unsigned int plt_rel_offset
)
1290 memcpy(pov
, plt_entry
, plt_entry_size
);
1291 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
1292 got_address
+ got_offset
);
1293 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 7, plt_rel_offset
);
1294 elfcpp::Swap
<32, false>::writeval(pov
+ 12, - (plt_offset
+ 12 + 4));
1298 // Subsequent entries in the PLT for a shared object.
1300 const unsigned char Output_data_plt_i386_dyn::plt_entry
[plt_entry_size
] =
1302 0xff, 0xa3, // jmp *offset(%ebx)
1303 0, 0, 0, 0, // replaced with offset of symbol in .got
1304 0x68, // pushl immediate
1305 0, 0, 0, 0, // replaced with offset into relocation table
1306 0xe9, // jmp relative
1307 0, 0, 0, 0 // replaced with offset to start of .plt
1311 Output_data_plt_i386_dyn::do_fill_plt_entry(unsigned char* pov
,
1312 elfcpp::Elf_types
<32>::Elf_Addr
,
1313 unsigned int got_offset
,
1314 unsigned int plt_offset
,
1315 unsigned int plt_rel_offset
)
1317 memcpy(pov
, plt_entry
, plt_entry_size
);
1318 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2, got_offset
);
1319 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 7, plt_rel_offset
);
1320 elfcpp::Swap
<32, false>::writeval(pov
+ 12, - (plt_offset
+ 12 + 4));
1324 // The .eh_frame unwind information for the PLT.
1327 Output_data_plt_i386::plt_eh_frame_cie
[plt_eh_frame_cie_size
] =
1330 'z', // Augmentation: augmentation size included.
1331 'R', // Augmentation: FDE encoding included.
1332 '\0', // End of augmentation string.
1333 1, // Code alignment factor.
1334 0x7c, // Data alignment factor.
1335 8, // Return address column.
1336 1, // Augmentation size.
1337 (elfcpp::DW_EH_PE_pcrel
// FDE encoding.
1338 | elfcpp::DW_EH_PE_sdata4
),
1339 elfcpp::DW_CFA_def_cfa
, 4, 4, // DW_CFA_def_cfa: r4 (esp) ofs 4.
1340 elfcpp::DW_CFA_offset
+ 8, 1, // DW_CFA_offset: r8 (eip) at cfa-4.
1341 elfcpp::DW_CFA_nop
, // Align to 16 bytes.
1346 Output_data_plt_i386_standard::plt_eh_frame_fde
[plt_eh_frame_fde_size
] =
1348 0, 0, 0, 0, // Replaced with offset to .plt.
1349 0, 0, 0, 0, // Replaced with size of .plt.
1350 0, // Augmentation size.
1351 elfcpp::DW_CFA_def_cfa_offset
, 8, // DW_CFA_def_cfa_offset: 8.
1352 elfcpp::DW_CFA_advance_loc
+ 6, // Advance 6 to __PLT__ + 6.
1353 elfcpp::DW_CFA_def_cfa_offset
, 12, // DW_CFA_def_cfa_offset: 12.
1354 elfcpp::DW_CFA_advance_loc
+ 10, // Advance 10 to __PLT__ + 16.
1355 elfcpp::DW_CFA_def_cfa_expression
, // DW_CFA_def_cfa_expression.
1356 11, // Block length.
1357 elfcpp::DW_OP_breg4
, 4, // Push %esp + 4.
1358 elfcpp::DW_OP_breg8
, 0, // Push %eip.
1359 elfcpp::DW_OP_lit15
, // Push 0xf.
1360 elfcpp::DW_OP_and
, // & (%eip & 0xf).
1361 elfcpp::DW_OP_lit11
, // Push 0xb.
1362 elfcpp::DW_OP_ge
, // >= ((%eip & 0xf) >= 0xb)
1363 elfcpp::DW_OP_lit2
, // Push 2.
1364 elfcpp::DW_OP_shl
, // << (((%eip & 0xf) >= 0xb) << 2)
1365 elfcpp::DW_OP_plus
, // + ((((%eip&0xf)>=0xb)<<2)+%esp+4
1366 elfcpp::DW_CFA_nop
, // Align to 32 bytes.
1372 // Write out the PLT. This uses the hand-coded instructions above,
1373 // and adjusts them as needed. This is all specified by the i386 ELF
1374 // Processor Supplement.
1377 Output_data_plt_i386::do_write(Output_file
* of
)
1379 const off_t offset
= this->offset();
1380 const section_size_type oview_size
=
1381 convert_to_section_size_type(this->data_size());
1382 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
1384 const off_t got_file_offset
= this->got_plt_
->offset();
1385 gold_assert(parameters
->incremental_update()
1386 || (got_file_offset
+ this->got_plt_
->data_size()
1387 == this->got_irelative_
->offset()));
1388 const section_size_type got_size
=
1389 convert_to_section_size_type(this->got_plt_
->data_size()
1390 + this->got_irelative_
->data_size());
1392 unsigned char* const got_view
= of
->get_output_view(got_file_offset
,
1395 unsigned char* pov
= oview
;
1397 elfcpp::Elf_types
<32>::Elf_Addr plt_address
= this->address();
1398 elfcpp::Elf_types
<32>::Elf_Addr got_address
= this->got_plt_
->address();
1400 this->fill_first_plt_entry(pov
, got_address
);
1401 pov
+= this->get_plt_entry_size();
1403 // The first three entries in the GOT are reserved, and are written
1404 // by Output_data_got_plt_i386::do_write.
1405 unsigned char* got_pov
= got_view
+ 12;
1407 const int rel_size
= elfcpp::Elf_sizes
<32>::rel_size
;
1409 unsigned int plt_offset
= this->get_plt_entry_size();
1410 unsigned int plt_rel_offset
= 0;
1411 unsigned int got_offset
= 12;
1412 const unsigned int count
= this->count_
+ this->irelative_count_
;
1413 for (unsigned int i
= 0;
1416 pov
+= this->get_plt_entry_size(),
1418 plt_offset
+= this->get_plt_entry_size(),
1419 plt_rel_offset
+= rel_size
,
1422 // Set and adjust the PLT entry itself.
1423 unsigned int lazy_offset
= this->fill_plt_entry(pov
,
1429 // Set the entry in the GOT.
1430 elfcpp::Swap
<32, false>::writeval(got_pov
,
1431 plt_address
+ plt_offset
+ lazy_offset
);
1434 // If any STT_GNU_IFUNC symbols have PLT entries, we need to change
1435 // the GOT to point to the actual symbol value, rather than point to
1436 // the PLT entry. That will let the dynamic linker call the right
1437 // function when resolving IRELATIVE relocations.
1438 unsigned char* got_irelative_view
= got_view
+ this->got_plt_
->data_size();
1439 for (std::vector
<Global_ifunc
>::const_iterator p
=
1440 this->global_ifuncs_
.begin();
1441 p
!= this->global_ifuncs_
.end();
1444 const Sized_symbol
<32>* ssym
=
1445 static_cast<const Sized_symbol
<32>*>(p
->sym
);
1446 elfcpp::Swap
<32, false>::writeval(got_irelative_view
+ p
->got_offset
,
1450 for (std::vector
<Local_ifunc
>::const_iterator p
=
1451 this->local_ifuncs_
.begin();
1452 p
!= this->local_ifuncs_
.end();
1455 const Symbol_value
<32>* psymval
=
1456 p
->object
->local_symbol(p
->local_sym_index
);
1457 elfcpp::Swap
<32, false>::writeval(got_irelative_view
+ p
->got_offset
,
1458 psymval
->value(p
->object
, 0));
1461 gold_assert(static_cast<section_size_type
>(pov
- oview
) == oview_size
);
1462 gold_assert(static_cast<section_size_type
>(got_pov
- got_view
) == got_size
);
1464 of
->write_output_view(offset
, oview_size
, oview
);
1465 of
->write_output_view(got_file_offset
, got_size
, got_view
);
1468 // Create the PLT section.
1471 Target_i386::make_plt_section(Symbol_table
* symtab
, Layout
* layout
)
1473 if (this->plt_
== NULL
)
1475 // Create the GOT sections first.
1476 this->got_section(symtab
, layout
);
1478 const bool dyn
= parameters
->options().output_is_position_independent();
1479 this->plt_
= this->make_data_plt(layout
,
1481 this->got_irelative_
,
1484 // Add unwind information if requested.
1485 if (parameters
->options().ld_generated_unwind_info())
1486 this->plt_
->add_eh_frame(layout
);
1488 layout
->add_output_section_data(".plt", elfcpp::SHT_PROGBITS
,
1490 | elfcpp::SHF_EXECINSTR
),
1491 this->plt_
, ORDER_PLT
, false);
1493 // Make the sh_info field of .rel.plt point to .plt.
1494 Output_section
* rel_plt_os
= this->plt_
->rel_plt()->output_section();
1495 rel_plt_os
->set_info_section(this->plt_
->output_section());
1499 // Create a PLT entry for a global symbol.
1502 Target_i386::make_plt_entry(Symbol_table
* symtab
, Layout
* layout
, Symbol
* gsym
)
1504 if (gsym
->has_plt_offset())
1506 if (this->plt_
== NULL
)
1507 this->make_plt_section(symtab
, layout
);
1508 this->plt_
->add_entry(symtab
, layout
, gsym
);
1511 // Make a PLT entry for a local STT_GNU_IFUNC symbol.
1514 Target_i386::make_local_ifunc_plt_entry(Symbol_table
* symtab
, Layout
* layout
,
1515 Sized_relobj_file
<32, false>* relobj
,
1516 unsigned int local_sym_index
)
1518 if (relobj
->local_has_plt_offset(local_sym_index
))
1520 if (this->plt_
== NULL
)
1521 this->make_plt_section(symtab
, layout
);
1522 unsigned int plt_offset
= this->plt_
->add_local_ifunc_entry(symtab
, layout
,
1525 relobj
->set_local_plt_offset(local_sym_index
, plt_offset
);
1528 // Return the number of entries in the PLT.
1531 Target_i386::plt_entry_count() const
1533 if (this->plt_
== NULL
)
1535 return this->plt_
->entry_count();
1538 // Return the offset of the first non-reserved PLT entry.
1541 Target_i386::first_plt_entry_offset() const
1543 return this->plt_
->first_plt_entry_offset();
1546 // Return the size of each PLT entry.
1549 Target_i386::plt_entry_size() const
1551 return this->plt_
->get_plt_entry_size();
1554 // Get the section to use for TLS_DESC relocations.
1556 Target_i386::Reloc_section
*
1557 Target_i386::rel_tls_desc_section(Layout
* layout
) const
1559 return this->plt_section()->rel_tls_desc(layout
);
1562 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
1565 Target_i386::define_tls_base_symbol(Symbol_table
* symtab
, Layout
* layout
)
1567 if (this->tls_base_symbol_defined_
)
1570 Output_segment
* tls_segment
= layout
->tls_segment();
1571 if (tls_segment
!= NULL
)
1573 bool is_exec
= parameters
->options().output_is_executable();
1574 symtab
->define_in_output_segment("_TLS_MODULE_BASE_", NULL
,
1575 Symbol_table::PREDEFINED
,
1579 elfcpp::STV_HIDDEN
, 0,
1581 ? Symbol::SEGMENT_END
1582 : Symbol::SEGMENT_START
),
1585 this->tls_base_symbol_defined_
= true;
1588 // Create a GOT entry for the TLS module index.
1591 Target_i386::got_mod_index_entry(Symbol_table
* symtab
, Layout
* layout
,
1592 Sized_relobj_file
<32, false>* object
)
1594 if (this->got_mod_index_offset_
== -1U)
1596 gold_assert(symtab
!= NULL
&& layout
!= NULL
&& object
!= NULL
);
1597 Reloc_section
* rel_dyn
= this->rel_dyn_section(layout
);
1598 Output_data_got
<32, false>* got
= this->got_section(symtab
, layout
);
1599 unsigned int got_offset
= got
->add_constant(0);
1600 rel_dyn
->add_local(object
, 0, elfcpp::R_386_TLS_DTPMOD32
, got
,
1602 got
->add_constant(0);
1603 this->got_mod_index_offset_
= got_offset
;
1605 return this->got_mod_index_offset_
;
1608 // Optimize the TLS relocation type based on what we know about the
1609 // symbol. IS_FINAL is true if the final address of this symbol is
1610 // known at link time.
1612 tls::Tls_optimization
1613 Target_i386::optimize_tls_reloc(bool is_final
, int r_type
)
1615 // If we are generating a shared library, then we can't do anything
1617 if (parameters
->options().shared())
1618 return tls::TLSOPT_NONE
;
1622 case elfcpp::R_386_TLS_GD
:
1623 case elfcpp::R_386_TLS_GOTDESC
:
1624 case elfcpp::R_386_TLS_DESC_CALL
:
1625 // These are General-Dynamic which permits fully general TLS
1626 // access. Since we know that we are generating an executable,
1627 // we can convert this to Initial-Exec. If we also know that
1628 // this is a local symbol, we can further switch to Local-Exec.
1630 return tls::TLSOPT_TO_LE
;
1631 return tls::TLSOPT_TO_IE
;
1633 case elfcpp::R_386_TLS_LDM
:
1634 // This is Local-Dynamic, which refers to a local symbol in the
1635 // dynamic TLS block. Since we know that we generating an
1636 // executable, we can switch to Local-Exec.
1637 return tls::TLSOPT_TO_LE
;
1639 case elfcpp::R_386_TLS_LDO_32
:
1640 // Another type of Local-Dynamic relocation.
1641 return tls::TLSOPT_TO_LE
;
1643 case elfcpp::R_386_TLS_IE
:
1644 case elfcpp::R_386_TLS_GOTIE
:
1645 case elfcpp::R_386_TLS_IE_32
:
1646 // These are Initial-Exec relocs which get the thread offset
1647 // from the GOT. If we know that we are linking against the
1648 // local symbol, we can switch to Local-Exec, which links the
1649 // thread offset into the instruction.
1651 return tls::TLSOPT_TO_LE
;
1652 return tls::TLSOPT_NONE
;
1654 case elfcpp::R_386_TLS_LE
:
1655 case elfcpp::R_386_TLS_LE_32
:
1656 // When we already have Local-Exec, there is nothing further we
1658 return tls::TLSOPT_NONE
;
1665 // Get the Reference_flags for a particular relocation.
1668 Target_i386::Scan::get_reference_flags(unsigned int r_type
)
1672 case elfcpp::R_386_NONE
:
1673 case elfcpp::R_386_GNU_VTINHERIT
:
1674 case elfcpp::R_386_GNU_VTENTRY
:
1675 case elfcpp::R_386_GOTPC
:
1676 // No symbol reference.
1679 case elfcpp::R_386_32
:
1680 case elfcpp::R_386_16
:
1681 case elfcpp::R_386_8
:
1682 return Symbol::ABSOLUTE_REF
;
1684 case elfcpp::R_386_PC32
:
1685 case elfcpp::R_386_PC16
:
1686 case elfcpp::R_386_PC8
:
1687 case elfcpp::R_386_GOTOFF
:
1688 return Symbol::RELATIVE_REF
;
1690 case elfcpp::R_386_PLT32
:
1691 return Symbol::FUNCTION_CALL
| Symbol::RELATIVE_REF
;
1693 case elfcpp::R_386_GOT32
:
1694 case elfcpp::R_386_GOT32X
:
1696 return Symbol::ABSOLUTE_REF
;
1698 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1699 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
1700 case elfcpp::R_386_TLS_DESC_CALL
:
1701 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1702 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1703 case elfcpp::R_386_TLS_IE
: // Initial-exec
1704 case elfcpp::R_386_TLS_IE_32
:
1705 case elfcpp::R_386_TLS_GOTIE
:
1706 case elfcpp::R_386_TLS_LE
: // Local-exec
1707 case elfcpp::R_386_TLS_LE_32
:
1708 return Symbol::TLS_REF
;
1710 case elfcpp::R_386_COPY
:
1711 case elfcpp::R_386_GLOB_DAT
:
1712 case elfcpp::R_386_JUMP_SLOT
:
1713 case elfcpp::R_386_RELATIVE
:
1714 case elfcpp::R_386_IRELATIVE
:
1715 case elfcpp::R_386_TLS_TPOFF
:
1716 case elfcpp::R_386_TLS_DTPMOD32
:
1717 case elfcpp::R_386_TLS_DTPOFF32
:
1718 case elfcpp::R_386_TLS_TPOFF32
:
1719 case elfcpp::R_386_TLS_DESC
:
1720 case elfcpp::R_386_32PLT
:
1721 case elfcpp::R_386_TLS_GD_32
:
1722 case elfcpp::R_386_TLS_GD_PUSH
:
1723 case elfcpp::R_386_TLS_GD_CALL
:
1724 case elfcpp::R_386_TLS_GD_POP
:
1725 case elfcpp::R_386_TLS_LDM_32
:
1726 case elfcpp::R_386_TLS_LDM_PUSH
:
1727 case elfcpp::R_386_TLS_LDM_CALL
:
1728 case elfcpp::R_386_TLS_LDM_POP
:
1729 case elfcpp::R_386_USED_BY_INTEL_200
:
1731 // Not expected. We will give an error later.
1736 // Report an unsupported relocation against a local symbol.
1739 Target_i386::Scan::unsupported_reloc_local(Sized_relobj_file
<32, false>* object
,
1740 unsigned int r_type
)
1742 gold_error(_("%s: unsupported reloc %u against local symbol"),
1743 object
->name().c_str(), r_type
);
1746 // Return whether we need to make a PLT entry for a relocation of a
1747 // given type against a STT_GNU_IFUNC symbol.
1750 Target_i386::Scan::reloc_needs_plt_for_ifunc(
1751 Sized_relobj_file
<32, false>* object
,
1752 unsigned int r_type
)
1754 int flags
= Scan::get_reference_flags(r_type
);
1755 if (flags
& Symbol::TLS_REF
)
1756 gold_error(_("%s: unsupported TLS reloc %u for IFUNC symbol"),
1757 object
->name().c_str(), r_type
);
1761 // Scan a relocation for a local symbol.
1764 Target_i386::Scan::local(Symbol_table
* symtab
,
1766 Target_i386
* target
,
1767 Sized_relobj_file
<32, false>* object
,
1768 unsigned int data_shndx
,
1769 Output_section
* output_section
,
1770 const elfcpp::Rel
<32, false>& reloc
,
1771 unsigned int r_type
,
1772 const elfcpp::Sym
<32, false>& lsym
,
1778 // A local STT_GNU_IFUNC symbol may require a PLT entry.
1779 if (lsym
.get_st_type() == elfcpp::STT_GNU_IFUNC
1780 && this->reloc_needs_plt_for_ifunc(object
, r_type
))
1782 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1783 target
->make_local_ifunc_plt_entry(symtab
, layout
, object
, r_sym
);
1788 case elfcpp::R_386_NONE
:
1789 case elfcpp::R_386_GNU_VTINHERIT
:
1790 case elfcpp::R_386_GNU_VTENTRY
:
1793 case elfcpp::R_386_32
:
1794 // If building a shared library (or a position-independent
1795 // executable), we need to create a dynamic relocation for
1796 // this location. The relocation applied at link time will
1797 // apply the link-time value, so we flag the location with
1798 // an R_386_RELATIVE relocation so the dynamic loader can
1799 // relocate it easily.
1800 if (parameters
->options().output_is_position_independent())
1802 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1803 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1804 rel_dyn
->add_local_relative(object
, r_sym
, elfcpp::R_386_RELATIVE
,
1805 output_section
, data_shndx
,
1806 reloc
.get_r_offset());
1810 case elfcpp::R_386_16
:
1811 case elfcpp::R_386_8
:
1812 // If building a shared library (or a position-independent
1813 // executable), we need to create a dynamic relocation for
1814 // this location. Because the addend needs to remain in the
1815 // data section, we need to be careful not to apply this
1816 // relocation statically.
1817 if (parameters
->options().output_is_position_independent())
1819 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1820 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1821 if (lsym
.get_st_type() != elfcpp::STT_SECTION
)
1822 rel_dyn
->add_local(object
, r_sym
, r_type
, output_section
,
1823 data_shndx
, reloc
.get_r_offset());
1826 gold_assert(lsym
.get_st_value() == 0);
1827 unsigned int shndx
= lsym
.get_st_shndx();
1829 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
,
1832 object
->error(_("section symbol %u has bad shndx %u"),
1835 rel_dyn
->add_local_section(object
, shndx
,
1836 r_type
, output_section
,
1837 data_shndx
, reloc
.get_r_offset());
1842 case elfcpp::R_386_PC32
:
1843 case elfcpp::R_386_PC16
:
1844 case elfcpp::R_386_PC8
:
1847 case elfcpp::R_386_PLT32
:
1848 // Since we know this is a local symbol, we can handle this as a
1852 case elfcpp::R_386_GOTOFF
:
1853 case elfcpp::R_386_GOTPC
:
1854 // We need a GOT section.
1855 target
->got_section(symtab
, layout
);
1858 case elfcpp::R_386_GOT32
:
1859 case elfcpp::R_386_GOT32X
:
1861 // We need GOT section.
1862 Output_data_got
<32, false>* got
= target
->got_section(symtab
, layout
);
1864 // If the relocation symbol isn't IFUNC,
1865 // and is local, then we will convert
1866 // mov foo@GOT(%reg), %reg
1868 // lea foo@GOTOFF(%reg), %reg
1869 // in Relocate::relocate.
1870 if (reloc
.get_r_offset() >= 2
1871 && lsym
.get_st_type() != elfcpp::STT_GNU_IFUNC
)
1873 section_size_type stype
;
1874 const unsigned char* view
= object
->section_contents(data_shndx
,
1876 if (view
[reloc
.get_r_offset() - 2] == 0x8b)
1880 // Otherwise, the symbol requires a GOT entry.
1881 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1883 // For a STT_GNU_IFUNC symbol we want the PLT offset. That
1884 // lets function pointers compare correctly with shared
1885 // libraries. Otherwise we would need an IRELATIVE reloc.
1887 if (lsym
.get_st_type() == elfcpp::STT_GNU_IFUNC
)
1888 is_new
= got
->add_local_plt(object
, r_sym
, GOT_TYPE_STANDARD
);
1890 is_new
= got
->add_local(object
, r_sym
, GOT_TYPE_STANDARD
);
1893 // If we are generating a shared object, we need to add a
1894 // dynamic RELATIVE relocation for this symbol's GOT entry.
1895 if (parameters
->options().output_is_position_independent())
1897 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1898 unsigned int got_offset
=
1899 object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
);
1900 rel_dyn
->add_local_relative(object
, r_sym
,
1901 elfcpp::R_386_RELATIVE
,
1908 // These are relocations which should only be seen by the
1909 // dynamic linker, and should never be seen here.
1910 case elfcpp::R_386_COPY
:
1911 case elfcpp::R_386_GLOB_DAT
:
1912 case elfcpp::R_386_JUMP_SLOT
:
1913 case elfcpp::R_386_RELATIVE
:
1914 case elfcpp::R_386_IRELATIVE
:
1915 case elfcpp::R_386_TLS_TPOFF
:
1916 case elfcpp::R_386_TLS_DTPMOD32
:
1917 case elfcpp::R_386_TLS_DTPOFF32
:
1918 case elfcpp::R_386_TLS_TPOFF32
:
1919 case elfcpp::R_386_TLS_DESC
:
1920 gold_error(_("%s: unexpected reloc %u in object file"),
1921 object
->name().c_str(), r_type
);
1924 // These are initial TLS relocs, which are expected when
1926 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1927 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
1928 case elfcpp::R_386_TLS_DESC_CALL
:
1929 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1930 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1931 case elfcpp::R_386_TLS_IE
: // Initial-exec
1932 case elfcpp::R_386_TLS_IE_32
:
1933 case elfcpp::R_386_TLS_GOTIE
:
1934 case elfcpp::R_386_TLS_LE
: // Local-exec
1935 case elfcpp::R_386_TLS_LE_32
:
1937 bool output_is_shared
= parameters
->options().shared();
1938 const tls::Tls_optimization optimized_type
1939 = Target_i386::optimize_tls_reloc(!output_is_shared
, r_type
);
1942 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1943 if (optimized_type
== tls::TLSOPT_NONE
)
1945 // Create a pair of GOT entries for the module index and
1946 // dtv-relative offset.
1947 Output_data_got
<32, false>* got
1948 = target
->got_section(symtab
, layout
);
1949 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1950 unsigned int shndx
= lsym
.get_st_shndx();
1952 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
, &is_ordinary
);
1954 object
->error(_("local symbol %u has bad shndx %u"),
1957 got
->add_local_pair_with_rel(object
, r_sym
, shndx
,
1959 target
->rel_dyn_section(layout
),
1960 elfcpp::R_386_TLS_DTPMOD32
);
1962 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1963 unsupported_reloc_local(object
, r_type
);
1966 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva)
1967 target
->define_tls_base_symbol(symtab
, layout
);
1968 if (optimized_type
== tls::TLSOPT_NONE
)
1970 // Create a double GOT entry with an R_386_TLS_DESC
1971 // reloc. The R_386_TLS_DESC reloc is resolved
1972 // lazily, so the GOT entry needs to be in an area in
1973 // .got.plt, not .got. Call got_section to make sure
1974 // the section has been created.
1975 target
->got_section(symtab
, layout
);
1976 Output_data_got
<32, false>* got
= target
->got_tlsdesc_section();
1977 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1978 if (!object
->local_has_got_offset(r_sym
, GOT_TYPE_TLS_DESC
))
1980 unsigned int got_offset
= got
->add_constant(0);
1981 // The local symbol value is stored in the second
1983 got
->add_local(object
, r_sym
, GOT_TYPE_TLS_DESC
);
1984 // That set the GOT offset of the local symbol to
1985 // point to the second entry, but we want it to
1986 // point to the first.
1987 object
->set_local_got_offset(r_sym
, GOT_TYPE_TLS_DESC
,
1989 Reloc_section
* rt
= target
->rel_tls_desc_section(layout
);
1990 rt
->add_absolute(elfcpp::R_386_TLS_DESC
, got
, got_offset
);
1993 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1994 unsupported_reloc_local(object
, r_type
);
1997 case elfcpp::R_386_TLS_DESC_CALL
:
2000 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
2001 if (optimized_type
== tls::TLSOPT_NONE
)
2003 // Create a GOT entry for the module index.
2004 target
->got_mod_index_entry(symtab
, layout
, object
);
2006 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2007 unsupported_reloc_local(object
, r_type
);
2010 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
2013 case elfcpp::R_386_TLS_IE
: // Initial-exec
2014 case elfcpp::R_386_TLS_IE_32
:
2015 case elfcpp::R_386_TLS_GOTIE
:
2016 layout
->set_has_static_tls();
2017 if (optimized_type
== tls::TLSOPT_NONE
)
2019 // For the R_386_TLS_IE relocation, we need to create a
2020 // dynamic relocation when building a shared library.
2021 if (r_type
== elfcpp::R_386_TLS_IE
2022 && parameters
->options().shared())
2024 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
2026 = elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
2027 rel_dyn
->add_local_relative(object
, r_sym
,
2028 elfcpp::R_386_RELATIVE
,
2029 output_section
, data_shndx
,
2030 reloc
.get_r_offset());
2032 // Create a GOT entry for the tp-relative offset.
2033 Output_data_got
<32, false>* got
2034 = target
->got_section(symtab
, layout
);
2035 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
2036 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_IE_32
2037 ? elfcpp::R_386_TLS_TPOFF32
2038 : elfcpp::R_386_TLS_TPOFF
);
2039 unsigned int got_type
= (r_type
== elfcpp::R_386_TLS_IE_32
2040 ? GOT_TYPE_TLS_OFFSET
2041 : GOT_TYPE_TLS_NOFFSET
);
2042 got
->add_local_with_rel(object
, r_sym
, got_type
,
2043 target
->rel_dyn_section(layout
),
2046 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2047 unsupported_reloc_local(object
, r_type
);
2050 case elfcpp::R_386_TLS_LE
: // Local-exec
2051 case elfcpp::R_386_TLS_LE_32
:
2052 layout
->set_has_static_tls();
2053 if (output_is_shared
)
2055 // We need to create a dynamic relocation.
2056 gold_assert(lsym
.get_st_type() != elfcpp::STT_SECTION
);
2057 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
2058 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_LE_32
2059 ? elfcpp::R_386_TLS_TPOFF32
2060 : elfcpp::R_386_TLS_TPOFF
);
2061 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
2062 rel_dyn
->add_local(object
, r_sym
, dyn_r_type
, output_section
,
2063 data_shndx
, reloc
.get_r_offset());
2073 case elfcpp::R_386_32PLT
:
2074 case elfcpp::R_386_TLS_GD_32
:
2075 case elfcpp::R_386_TLS_GD_PUSH
:
2076 case elfcpp::R_386_TLS_GD_CALL
:
2077 case elfcpp::R_386_TLS_GD_POP
:
2078 case elfcpp::R_386_TLS_LDM_32
:
2079 case elfcpp::R_386_TLS_LDM_PUSH
:
2080 case elfcpp::R_386_TLS_LDM_CALL
:
2081 case elfcpp::R_386_TLS_LDM_POP
:
2082 case elfcpp::R_386_USED_BY_INTEL_200
:
2084 unsupported_reloc_local(object
, r_type
);
2089 // Report an unsupported relocation against a global symbol.
2092 Target_i386::Scan::unsupported_reloc_global(
2093 Sized_relobj_file
<32, false>* object
,
2094 unsigned int r_type
,
2097 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
2098 object
->name().c_str(), r_type
, gsym
->demangled_name().c_str());
2102 Target_i386::Scan::possible_function_pointer_reloc(unsigned int r_type
)
2106 case elfcpp::R_386_32
:
2107 case elfcpp::R_386_16
:
2108 case elfcpp::R_386_8
:
2109 case elfcpp::R_386_GOTOFF
:
2110 case elfcpp::R_386_GOT32
:
2111 case elfcpp::R_386_GOT32X
:
2122 Target_i386::Scan::local_reloc_may_be_function_pointer(
2126 Sized_relobj_file
<32, false>* ,
2129 const elfcpp::Rel
<32, false>& ,
2130 unsigned int r_type
,
2131 const elfcpp::Sym
<32, false>&)
2133 return possible_function_pointer_reloc(r_type
);
2137 Target_i386::Scan::global_reloc_may_be_function_pointer(
2141 Sized_relobj_file
<32, false>* ,
2144 const elfcpp::Rel
<32, false>& ,
2145 unsigned int r_type
,
2148 return possible_function_pointer_reloc(r_type
);
2151 // Scan a relocation for a global symbol.
2154 Target_i386::Scan::global(Symbol_table
* symtab
,
2156 Target_i386
* target
,
2157 Sized_relobj_file
<32, false>* object
,
2158 unsigned int data_shndx
,
2159 Output_section
* output_section
,
2160 const elfcpp::Rel
<32, false>& reloc
,
2161 unsigned int r_type
,
2164 // A STT_GNU_IFUNC symbol may require a PLT entry.
2165 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
2166 && this->reloc_needs_plt_for_ifunc(object
, r_type
))
2167 target
->make_plt_entry(symtab
, layout
, gsym
);
2171 case elfcpp::R_386_NONE
:
2172 case elfcpp::R_386_GNU_VTINHERIT
:
2173 case elfcpp::R_386_GNU_VTENTRY
:
2176 case elfcpp::R_386_32
:
2177 case elfcpp::R_386_16
:
2178 case elfcpp::R_386_8
:
2180 // Make a PLT entry if necessary.
2181 if (gsym
->needs_plt_entry())
2183 target
->make_plt_entry(symtab
, layout
, gsym
);
2184 // Since this is not a PC-relative relocation, we may be
2185 // taking the address of a function. In that case we need to
2186 // set the entry in the dynamic symbol table to the address of
2188 if (gsym
->is_from_dynobj() && !parameters
->options().shared())
2189 gsym
->set_needs_dynsym_value();
2191 // Make a dynamic relocation if necessary.
2192 if (gsym
->needs_dynamic_reloc(Scan::get_reference_flags(r_type
)))
2194 if (!parameters
->options().output_is_position_independent()
2195 && gsym
->may_need_copy_reloc())
2197 target
->copy_reloc(symtab
, layout
, object
,
2198 data_shndx
, output_section
, gsym
, reloc
);
2200 else if (r_type
== elfcpp::R_386_32
2201 && gsym
->type() == elfcpp::STT_GNU_IFUNC
2202 && gsym
->can_use_relative_reloc(false)
2203 && !gsym
->is_from_dynobj()
2204 && !gsym
->is_undefined()
2205 && !gsym
->is_preemptible())
2207 // Use an IRELATIVE reloc for a locally defined
2208 // STT_GNU_IFUNC symbol. This makes a function
2209 // address in a PIE executable match the address in a
2210 // shared library that it links against.
2211 Reloc_section
* rel_dyn
= target
->rel_irelative_section(layout
);
2212 rel_dyn
->add_symbolless_global_addend(gsym
,
2213 elfcpp::R_386_IRELATIVE
,
2216 reloc
.get_r_offset());
2218 else if (r_type
== elfcpp::R_386_32
2219 && gsym
->can_use_relative_reloc(false))
2221 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
2222 rel_dyn
->add_global_relative(gsym
, elfcpp::R_386_RELATIVE
,
2223 output_section
, object
,
2224 data_shndx
, reloc
.get_r_offset());
2228 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
2229 rel_dyn
->add_global(gsym
, r_type
, output_section
, object
,
2230 data_shndx
, reloc
.get_r_offset());
2236 case elfcpp::R_386_PC32
:
2237 case elfcpp::R_386_PC16
:
2238 case elfcpp::R_386_PC8
:
2240 // Make a PLT entry if necessary.
2241 if (gsym
->needs_plt_entry())
2243 // These relocations are used for function calls only in
2244 // non-PIC code. For a 32-bit relocation in a shared library,
2245 // we'll need a text relocation anyway, so we can skip the
2246 // PLT entry and let the dynamic linker bind the call directly
2247 // to the target. For smaller relocations, we should use a
2248 // PLT entry to ensure that the call can reach.
2249 if (!parameters
->options().shared()
2250 || r_type
!= elfcpp::R_386_PC32
)
2251 target
->make_plt_entry(symtab
, layout
, gsym
);
2253 // Make a dynamic relocation if necessary.
2254 if (gsym
->needs_dynamic_reloc(Scan::get_reference_flags(r_type
)))
2256 if (parameters
->options().output_is_executable()
2257 && gsym
->may_need_copy_reloc())
2259 target
->copy_reloc(symtab
, layout
, object
,
2260 data_shndx
, output_section
, gsym
, reloc
);
2264 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
2265 rel_dyn
->add_global(gsym
, r_type
, output_section
, object
,
2266 data_shndx
, reloc
.get_r_offset());
2272 case elfcpp::R_386_GOT32
:
2273 case elfcpp::R_386_GOT32X
:
2275 // The symbol requires a GOT section.
2276 Output_data_got
<32, false>* got
= target
->got_section(symtab
, layout
);
2278 // If we convert this from
2279 // mov foo@GOT(%reg), %reg
2281 // lea foo@GOTOFF(%reg), %reg
2282 // in Relocate::relocate, then there is nothing to do here.
2283 if (reloc
.get_r_offset() >= 2
2284 && Target_i386::can_convert_mov_to_lea(gsym
))
2286 section_size_type stype
;
2287 const unsigned char* view
= object
->section_contents(data_shndx
,
2289 if (view
[reloc
.get_r_offset() - 2] == 0x8b)
2293 if (gsym
->final_value_is_known())
2295 // For a STT_GNU_IFUNC symbol we want the PLT address.
2296 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
)
2297 got
->add_global_plt(gsym
, GOT_TYPE_STANDARD
);
2299 got
->add_global(gsym
, GOT_TYPE_STANDARD
);
2303 // If this symbol is not fully resolved, we need to add a
2304 // GOT entry with a dynamic relocation.
2305 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
2307 // Use a GLOB_DAT rather than a RELATIVE reloc if:
2309 // 1) The symbol may be defined in some other module.
2311 // 2) We are building a shared library and this is a
2312 // protected symbol; using GLOB_DAT means that the dynamic
2313 // linker can use the address of the PLT in the main
2314 // executable when appropriate so that function address
2315 // comparisons work.
2317 // 3) This is a STT_GNU_IFUNC symbol in position dependent
2318 // code, again so that function address comparisons work.
2319 if (gsym
->is_from_dynobj()
2320 || gsym
->is_undefined()
2321 || gsym
->is_preemptible()
2322 || (gsym
->visibility() == elfcpp::STV_PROTECTED
2323 && parameters
->options().shared())
2324 || (gsym
->type() == elfcpp::STT_GNU_IFUNC
2325 && parameters
->options().output_is_position_independent()))
2326 got
->add_global_with_rel(gsym
, GOT_TYPE_STANDARD
,
2327 rel_dyn
, elfcpp::R_386_GLOB_DAT
);
2330 // For a STT_GNU_IFUNC symbol we want to write the PLT
2331 // offset into the GOT, so that function pointer
2332 // comparisons work correctly.
2334 if (gsym
->type() != elfcpp::STT_GNU_IFUNC
)
2335 is_new
= got
->add_global(gsym
, GOT_TYPE_STANDARD
);
2338 is_new
= got
->add_global_plt(gsym
, GOT_TYPE_STANDARD
);
2339 // Tell the dynamic linker to use the PLT address
2340 // when resolving relocations.
2341 if (gsym
->is_from_dynobj()
2342 && !parameters
->options().shared())
2343 gsym
->set_needs_dynsym_value();
2347 unsigned int got_off
= gsym
->got_offset(GOT_TYPE_STANDARD
);
2348 rel_dyn
->add_global_relative(gsym
, elfcpp::R_386_RELATIVE
,
2356 case elfcpp::R_386_PLT32
:
2357 // If the symbol is fully resolved, this is just a PC32 reloc.
2358 // Otherwise we need a PLT entry.
2359 if (gsym
->final_value_is_known())
2361 // If building a shared library, we can also skip the PLT entry
2362 // if the symbol is defined in the output file and is protected
2364 if (gsym
->is_defined()
2365 && !gsym
->is_from_dynobj()
2366 && !gsym
->is_preemptible())
2368 target
->make_plt_entry(symtab
, layout
, gsym
);
2371 case elfcpp::R_386_GOTOFF
:
2372 case elfcpp::R_386_GOTPC
:
2373 // We need a GOT section.
2374 target
->got_section(symtab
, layout
);
2377 // These are relocations which should only be seen by the
2378 // dynamic linker, and should never be seen here.
2379 case elfcpp::R_386_COPY
:
2380 case elfcpp::R_386_GLOB_DAT
:
2381 case elfcpp::R_386_JUMP_SLOT
:
2382 case elfcpp::R_386_RELATIVE
:
2383 case elfcpp::R_386_IRELATIVE
:
2384 case elfcpp::R_386_TLS_TPOFF
:
2385 case elfcpp::R_386_TLS_DTPMOD32
:
2386 case elfcpp::R_386_TLS_DTPOFF32
:
2387 case elfcpp::R_386_TLS_TPOFF32
:
2388 case elfcpp::R_386_TLS_DESC
:
2389 gold_error(_("%s: unexpected reloc %u in object file"),
2390 object
->name().c_str(), r_type
);
2393 // These are initial tls relocs, which are expected when
2395 case elfcpp::R_386_TLS_GD
: // Global-dynamic
2396 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
2397 case elfcpp::R_386_TLS_DESC_CALL
:
2398 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
2399 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
2400 case elfcpp::R_386_TLS_IE
: // Initial-exec
2401 case elfcpp::R_386_TLS_IE_32
:
2402 case elfcpp::R_386_TLS_GOTIE
:
2403 case elfcpp::R_386_TLS_LE
: // Local-exec
2404 case elfcpp::R_386_TLS_LE_32
:
2406 const bool is_final
= gsym
->final_value_is_known();
2407 const tls::Tls_optimization optimized_type
2408 = Target_i386::optimize_tls_reloc(is_final
, r_type
);
2411 case elfcpp::R_386_TLS_GD
: // Global-dynamic
2412 if (optimized_type
== tls::TLSOPT_NONE
)
2414 // Create a pair of GOT entries for the module index and
2415 // dtv-relative offset.
2416 Output_data_got
<32, false>* got
2417 = target
->got_section(symtab
, layout
);
2418 got
->add_global_pair_with_rel(gsym
, GOT_TYPE_TLS_PAIR
,
2419 target
->rel_dyn_section(layout
),
2420 elfcpp::R_386_TLS_DTPMOD32
,
2421 elfcpp::R_386_TLS_DTPOFF32
);
2423 else if (optimized_type
== tls::TLSOPT_TO_IE
)
2425 // Create a GOT entry for the tp-relative offset.
2426 Output_data_got
<32, false>* got
2427 = target
->got_section(symtab
, layout
);
2428 got
->add_global_with_rel(gsym
, GOT_TYPE_TLS_NOFFSET
,
2429 target
->rel_dyn_section(layout
),
2430 elfcpp::R_386_TLS_TPOFF
);
2432 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2433 unsupported_reloc_global(object
, r_type
, gsym
);
2436 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (~oliva url)
2437 target
->define_tls_base_symbol(symtab
, layout
);
2438 if (optimized_type
== tls::TLSOPT_NONE
)
2440 // Create a double GOT entry with an R_386_TLS_DESC
2441 // reloc. The R_386_TLS_DESC reloc is resolved
2442 // lazily, so the GOT entry needs to be in an area in
2443 // .got.plt, not .got. Call got_section to make sure
2444 // the section has been created.
2445 target
->got_section(symtab
, layout
);
2446 Output_data_got
<32, false>* got
= target
->got_tlsdesc_section();
2447 Reloc_section
* rt
= target
->rel_tls_desc_section(layout
);
2448 got
->add_global_pair_with_rel(gsym
, GOT_TYPE_TLS_DESC
, rt
,
2449 elfcpp::R_386_TLS_DESC
, 0);
2451 else if (optimized_type
== tls::TLSOPT_TO_IE
)
2453 // Create a GOT entry for the tp-relative offset.
2454 Output_data_got
<32, false>* got
2455 = target
->got_section(symtab
, layout
);
2456 got
->add_global_with_rel(gsym
, GOT_TYPE_TLS_NOFFSET
,
2457 target
->rel_dyn_section(layout
),
2458 elfcpp::R_386_TLS_TPOFF
);
2460 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2461 unsupported_reloc_global(object
, r_type
, gsym
);
2464 case elfcpp::R_386_TLS_DESC_CALL
:
2467 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
2468 if (optimized_type
== tls::TLSOPT_NONE
)
2470 // Create a GOT entry for the module index.
2471 target
->got_mod_index_entry(symtab
, layout
, object
);
2473 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2474 unsupported_reloc_global(object
, r_type
, gsym
);
2477 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
2480 case elfcpp::R_386_TLS_IE
: // Initial-exec
2481 case elfcpp::R_386_TLS_IE_32
:
2482 case elfcpp::R_386_TLS_GOTIE
:
2483 layout
->set_has_static_tls();
2484 if (optimized_type
== tls::TLSOPT_NONE
)
2486 // For the R_386_TLS_IE relocation, we need to create a
2487 // dynamic relocation when building a shared library.
2488 if (r_type
== elfcpp::R_386_TLS_IE
2489 && parameters
->options().shared())
2491 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
2492 rel_dyn
->add_global_relative(gsym
, elfcpp::R_386_RELATIVE
,
2493 output_section
, object
,
2495 reloc
.get_r_offset());
2497 // Create a GOT entry for the tp-relative offset.
2498 Output_data_got
<32, false>* got
2499 = target
->got_section(symtab
, layout
);
2500 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_IE_32
2501 ? elfcpp::R_386_TLS_TPOFF32
2502 : elfcpp::R_386_TLS_TPOFF
);
2503 unsigned int got_type
= (r_type
== elfcpp::R_386_TLS_IE_32
2504 ? GOT_TYPE_TLS_OFFSET
2505 : GOT_TYPE_TLS_NOFFSET
);
2506 got
->add_global_with_rel(gsym
, got_type
,
2507 target
->rel_dyn_section(layout
),
2510 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2511 unsupported_reloc_global(object
, r_type
, gsym
);
2514 case elfcpp::R_386_TLS_LE
: // Local-exec
2515 case elfcpp::R_386_TLS_LE_32
:
2516 layout
->set_has_static_tls();
2517 if (parameters
->options().shared())
2519 // We need to create a dynamic relocation.
2520 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_LE_32
2521 ? elfcpp::R_386_TLS_TPOFF32
2522 : elfcpp::R_386_TLS_TPOFF
);
2523 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
2524 rel_dyn
->add_global(gsym
, dyn_r_type
, output_section
, object
,
2525 data_shndx
, reloc
.get_r_offset());
2535 case elfcpp::R_386_32PLT
:
2536 case elfcpp::R_386_TLS_GD_32
:
2537 case elfcpp::R_386_TLS_GD_PUSH
:
2538 case elfcpp::R_386_TLS_GD_CALL
:
2539 case elfcpp::R_386_TLS_GD_POP
:
2540 case elfcpp::R_386_TLS_LDM_32
:
2541 case elfcpp::R_386_TLS_LDM_PUSH
:
2542 case elfcpp::R_386_TLS_LDM_CALL
:
2543 case elfcpp::R_386_TLS_LDM_POP
:
2544 case elfcpp::R_386_USED_BY_INTEL_200
:
2546 unsupported_reloc_global(object
, r_type
, gsym
);
2551 // Process relocations for gc.
2554 Target_i386::gc_process_relocs(Symbol_table
* symtab
,
2556 Sized_relobj_file
<32, false>* object
,
2557 unsigned int data_shndx
,
2559 const unsigned char* prelocs
,
2561 Output_section
* output_section
,
2562 bool needs_special_offset_handling
,
2563 size_t local_symbol_count
,
2564 const unsigned char* plocal_symbols
)
2566 gold::gc_process_relocs
<32, false, Target_i386
, elfcpp::SHT_REL
,
2568 Target_i386::Relocatable_size_for_reloc
>(
2577 needs_special_offset_handling
,
2582 // Scan relocations for a section.
2585 Target_i386::scan_relocs(Symbol_table
* symtab
,
2587 Sized_relobj_file
<32, false>* object
,
2588 unsigned int data_shndx
,
2589 unsigned int sh_type
,
2590 const unsigned char* prelocs
,
2592 Output_section
* output_section
,
2593 bool needs_special_offset_handling
,
2594 size_t local_symbol_count
,
2595 const unsigned char* plocal_symbols
)
2597 if (sh_type
== elfcpp::SHT_RELA
)
2599 gold_error(_("%s: unsupported RELA reloc section"),
2600 object
->name().c_str());
2604 gold::scan_relocs
<32, false, Target_i386
, elfcpp::SHT_REL
,
2614 needs_special_offset_handling
,
2619 // Finalize the sections.
2622 Target_i386::do_finalize_sections(
2624 const Input_objects
*,
2625 Symbol_table
* symtab
)
2627 const Reloc_section
* rel_plt
= (this->plt_
== NULL
2629 : this->plt_
->rel_plt());
2630 layout
->add_target_dynamic_tags(true, this->got_plt_
, rel_plt
,
2631 this->rel_dyn_
, true, false);
2633 // Emit any relocs we saved in an attempt to avoid generating COPY
2635 if (this->copy_relocs_
.any_saved_relocs())
2636 this->copy_relocs_
.emit(this->rel_dyn_section(layout
));
2638 // Set the size of the _GLOBAL_OFFSET_TABLE_ symbol to the size of
2639 // the .got.plt section.
2640 Symbol
* sym
= this->global_offset_table_
;
2643 uint32_t data_size
= this->got_plt_
->current_data_size();
2644 symtab
->get_sized_symbol
<32>(sym
)->set_symsize(data_size
);
2647 if (parameters
->doing_static_link()
2648 && (this->plt_
== NULL
|| !this->plt_
->has_irelative_section()))
2650 // If linking statically, make sure that the __rel_iplt symbols
2651 // were defined if necessary, even if we didn't create a PLT.
2652 static const Define_symbol_in_segment syms
[] =
2655 "__rel_iplt_start", // name
2656 elfcpp::PT_LOAD
, // segment_type
2657 elfcpp::PF_W
, // segment_flags_set
2658 elfcpp::PF(0), // segment_flags_clear
2661 elfcpp::STT_NOTYPE
, // type
2662 elfcpp::STB_GLOBAL
, // binding
2663 elfcpp::STV_HIDDEN
, // visibility
2665 Symbol::SEGMENT_START
, // offset_from_base
2669 "__rel_iplt_end", // name
2670 elfcpp::PT_LOAD
, // segment_type
2671 elfcpp::PF_W
, // segment_flags_set
2672 elfcpp::PF(0), // segment_flags_clear
2675 elfcpp::STT_NOTYPE
, // type
2676 elfcpp::STB_GLOBAL
, // binding
2677 elfcpp::STV_HIDDEN
, // visibility
2679 Symbol::SEGMENT_START
, // offset_from_base
2684 symtab
->define_symbols(layout
, 2, syms
,
2685 layout
->script_options()->saw_sections_clause());
2689 // Return whether a direct absolute static relocation needs to be applied.
2690 // In cases where Scan::local() or Scan::global() has created
2691 // a dynamic relocation other than R_386_RELATIVE, the addend
2692 // of the relocation is carried in the data, and we must not
2693 // apply the static relocation.
2696 Target_i386::Relocate::should_apply_static_reloc(const Sized_symbol
<32>* gsym
,
2697 unsigned int r_type
,
2699 Output_section
* output_section
)
2701 // If the output section is not allocated, then we didn't call
2702 // scan_relocs, we didn't create a dynamic reloc, and we must apply
2704 if ((output_section
->flags() & elfcpp::SHF_ALLOC
) == 0)
2707 int ref_flags
= Scan::get_reference_flags(r_type
);
2709 // For local symbols, we will have created a non-RELATIVE dynamic
2710 // relocation only if (a) the output is position independent,
2711 // (b) the relocation is absolute (not pc- or segment-relative), and
2712 // (c) the relocation is not 32 bits wide.
2714 return !(parameters
->options().output_is_position_independent()
2715 && (ref_flags
& Symbol::ABSOLUTE_REF
)
2718 // For global symbols, we use the same helper routines used in the
2719 // scan pass. If we did not create a dynamic relocation, or if we
2720 // created a RELATIVE dynamic relocation, we should apply the static
2722 bool has_dyn
= gsym
->needs_dynamic_reloc(ref_flags
);
2723 bool is_rel
= (ref_flags
& Symbol::ABSOLUTE_REF
)
2724 && gsym
->can_use_relative_reloc(ref_flags
2725 & Symbol::FUNCTION_CALL
);
2726 return !has_dyn
|| is_rel
;
2729 // Perform a relocation.
2732 Target_i386::Relocate::relocate(const Relocate_info
<32, false>* relinfo
,
2734 Target_i386
* target
,
2735 Output_section
* output_section
,
2737 const unsigned char* preloc
,
2738 const Sized_symbol
<32>* gsym
,
2739 const Symbol_value
<32>* psymval
,
2740 unsigned char* view
,
2741 elfcpp::Elf_types
<32>::Elf_Addr address
,
2742 section_size_type view_size
)
2744 const elfcpp::Rel
<32, false> rel(preloc
);
2745 unsigned int r_type
= elfcpp::elf_r_type
<32>(rel
.get_r_info());
2747 if (this->skip_call_tls_get_addr_
)
2749 if ((r_type
!= elfcpp::R_386_PLT32
2750 && r_type
!= elfcpp::R_386_PC32
)
2752 || strcmp(gsym
->name(), "___tls_get_addr") != 0)
2753 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2754 _("missing expected TLS relocation"));
2757 this->skip_call_tls_get_addr_
= false;
2765 const Sized_relobj_file
<32, false>* object
= relinfo
->object
;
2767 // Pick the value to use for symbols defined in shared objects.
2768 Symbol_value
<32> symval
;
2770 && gsym
->type() == elfcpp::STT_GNU_IFUNC
2771 && r_type
== elfcpp::R_386_32
2772 && gsym
->needs_dynamic_reloc(Scan::get_reference_flags(r_type
))
2773 && gsym
->can_use_relative_reloc(false)
2774 && !gsym
->is_from_dynobj()
2775 && !gsym
->is_undefined()
2776 && !gsym
->is_preemptible())
2778 // In this case we are generating a R_386_IRELATIVE reloc. We
2779 // want to use the real value of the symbol, not the PLT offset.
2781 else if (gsym
!= NULL
2782 && gsym
->use_plt_offset(Scan::get_reference_flags(r_type
)))
2784 symval
.set_output_value(target
->plt_address_for_global(gsym
));
2787 else if (gsym
== NULL
&& psymval
->is_ifunc_symbol())
2789 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
2790 if (object
->local_has_plt_offset(r_sym
))
2792 symval
.set_output_value(target
->plt_address_for_local(object
, r_sym
));
2801 case elfcpp::R_386_NONE
:
2802 case elfcpp::R_386_GNU_VTINHERIT
:
2803 case elfcpp::R_386_GNU_VTENTRY
:
2806 case elfcpp::R_386_32
:
2807 if (should_apply_static_reloc(gsym
, r_type
, true, output_section
))
2808 Relocate_functions
<32, false>::rel32(view
, object
, psymval
);
2811 case elfcpp::R_386_PC32
:
2812 if (should_apply_static_reloc(gsym
, r_type
, true, output_section
))
2813 Relocate_functions
<32, false>::pcrel32(view
, object
, psymval
, address
);
2816 case elfcpp::R_386_16
:
2817 if (should_apply_static_reloc(gsym
, r_type
, false, output_section
))
2818 Relocate_functions
<32, false>::rel16(view
, object
, psymval
);
2821 case elfcpp::R_386_PC16
:
2822 if (should_apply_static_reloc(gsym
, r_type
, false, output_section
))
2823 Relocate_functions
<32, false>::pcrel16(view
, object
, psymval
, address
);
2826 case elfcpp::R_386_8
:
2827 if (should_apply_static_reloc(gsym
, r_type
, false, output_section
))
2828 Relocate_functions
<32, false>::rel8(view
, object
, psymval
);
2831 case elfcpp::R_386_PC8
:
2832 if (should_apply_static_reloc(gsym
, r_type
, false, output_section
))
2833 Relocate_functions
<32, false>::pcrel8(view
, object
, psymval
, address
);
2836 case elfcpp::R_386_PLT32
:
2837 gold_assert(gsym
== NULL
2838 || gsym
->has_plt_offset()
2839 || gsym
->final_value_is_known()
2840 || (gsym
->is_defined()
2841 && !gsym
->is_from_dynobj()
2842 && !gsym
->is_preemptible()));
2843 Relocate_functions
<32, false>::pcrel32(view
, object
, psymval
, address
);
2846 case elfcpp::R_386_GOT32
:
2847 case elfcpp::R_386_GOT32X
:
2848 baseless
= (view
[-1] & 0xc7) == 0x5;
2849 // R_386_GOT32 and R_386_GOT32X don't work without base register
2850 // when generating a position-independent output file.
2852 && parameters
->options().output_is_position_independent())
2855 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2856 _("unexpected reloc %u against global symbol %s without base register in object file when generating a position-independent output file"),
2857 r_type
, gsym
->demangled_name().c_str());
2859 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2860 _("unexpected reloc %u against local symbol without base register in object file when generating a position-independent output file"),
2865 // mov foo@GOT(%reg), %reg
2867 // lea foo@GOTOFF(%reg), %reg
2869 if (rel
.get_r_offset() >= 2
2871 && ((gsym
== NULL
&& !psymval
->is_ifunc_symbol())
2873 && Target_i386::can_convert_mov_to_lea(gsym
))))
2876 elfcpp::Elf_types
<32>::Elf_Addr value
;
2877 value
= psymval
->value(object
, 0);
2878 // Don't subtract the .got.plt section address for baseless
2881 value
-= target
->got_plt_section()->address();
2882 Relocate_functions
<32, false>::rel32(view
, value
);
2886 // The GOT pointer points to the end of the GOT section.
2887 // We need to subtract the size of the GOT section to get
2888 // the actual offset to use in the relocation.
2889 unsigned int got_offset
= 0;
2892 gold_assert(gsym
->has_got_offset(GOT_TYPE_STANDARD
));
2893 got_offset
= (gsym
->got_offset(GOT_TYPE_STANDARD
)
2894 - target
->got_size());
2898 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
2899 gold_assert(object
->local_has_got_offset(r_sym
, GOT_TYPE_STANDARD
));
2900 got_offset
= (object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
)
2901 - target
->got_size());
2903 // Add the .got.plt section address for baseless addressing.
2905 got_offset
+= target
->got_plt_section()->address();
2906 Relocate_functions
<32, false>::rel32(view
, got_offset
);
2910 case elfcpp::R_386_GOTOFF
:
2912 elfcpp::Elf_types
<32>::Elf_Addr value
;
2913 value
= (psymval
->value(object
, 0)
2914 - target
->got_plt_section()->address());
2915 Relocate_functions
<32, false>::rel32(view
, value
);
2919 case elfcpp::R_386_GOTPC
:
2921 elfcpp::Elf_types
<32>::Elf_Addr value
;
2922 value
= target
->got_plt_section()->address();
2923 Relocate_functions
<32, false>::pcrel32(view
, value
, address
);
2927 case elfcpp::R_386_COPY
:
2928 case elfcpp::R_386_GLOB_DAT
:
2929 case elfcpp::R_386_JUMP_SLOT
:
2930 case elfcpp::R_386_RELATIVE
:
2931 case elfcpp::R_386_IRELATIVE
:
2932 // These are outstanding tls relocs, which are unexpected when
2934 case elfcpp::R_386_TLS_TPOFF
:
2935 case elfcpp::R_386_TLS_DTPMOD32
:
2936 case elfcpp::R_386_TLS_DTPOFF32
:
2937 case elfcpp::R_386_TLS_TPOFF32
:
2938 case elfcpp::R_386_TLS_DESC
:
2939 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2940 _("unexpected reloc %u in object file"),
2944 // These are initial tls relocs, which are expected when
2946 case elfcpp::R_386_TLS_GD
: // Global-dynamic
2947 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
2948 case elfcpp::R_386_TLS_DESC_CALL
:
2949 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
2950 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
2951 case elfcpp::R_386_TLS_IE
: // Initial-exec
2952 case elfcpp::R_386_TLS_IE_32
:
2953 case elfcpp::R_386_TLS_GOTIE
:
2954 case elfcpp::R_386_TLS_LE
: // Local-exec
2955 case elfcpp::R_386_TLS_LE_32
:
2956 this->relocate_tls(relinfo
, target
, relnum
, rel
, r_type
, gsym
, psymval
,
2957 view
, address
, view_size
);
2960 case elfcpp::R_386_32PLT
:
2961 case elfcpp::R_386_TLS_GD_32
:
2962 case elfcpp::R_386_TLS_GD_PUSH
:
2963 case elfcpp::R_386_TLS_GD_CALL
:
2964 case elfcpp::R_386_TLS_GD_POP
:
2965 case elfcpp::R_386_TLS_LDM_32
:
2966 case elfcpp::R_386_TLS_LDM_PUSH
:
2967 case elfcpp::R_386_TLS_LDM_CALL
:
2968 case elfcpp::R_386_TLS_LDM_POP
:
2969 case elfcpp::R_386_USED_BY_INTEL_200
:
2971 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2972 _("unsupported reloc %u"),
2980 // Perform a TLS relocation.
2983 Target_i386::Relocate::relocate_tls(const Relocate_info
<32, false>* relinfo
,
2984 Target_i386
* target
,
2986 const elfcpp::Rel
<32, false>& rel
,
2987 unsigned int r_type
,
2988 const Sized_symbol
<32>* gsym
,
2989 const Symbol_value
<32>* psymval
,
2990 unsigned char* view
,
2991 elfcpp::Elf_types
<32>::Elf_Addr
,
2992 section_size_type view_size
)
2994 Output_segment
* tls_segment
= relinfo
->layout
->tls_segment();
2996 const Sized_relobj_file
<32, false>* object
= relinfo
->object
;
2998 elfcpp::Elf_types
<32>::Elf_Addr value
= psymval
->value(object
, 0);
3000 const bool is_final
= (gsym
== NULL
3001 ? !parameters
->options().shared()
3002 : gsym
->final_value_is_known());
3003 const tls::Tls_optimization optimized_type
3004 = Target_i386::optimize_tls_reloc(is_final
, r_type
);
3007 case elfcpp::R_386_TLS_GD
: // Global-dynamic
3008 if (optimized_type
== tls::TLSOPT_TO_LE
)
3010 if (tls_segment
== NULL
)
3012 gold_assert(parameters
->errors()->error_count() > 0
3013 || issue_undefined_symbol_error(gsym
));
3016 this->tls_gd_to_le(relinfo
, relnum
, tls_segment
,
3017 rel
, r_type
, value
, view
,
3023 unsigned int got_type
= (optimized_type
== tls::TLSOPT_TO_IE
3024 ? GOT_TYPE_TLS_NOFFSET
3025 : GOT_TYPE_TLS_PAIR
);
3026 unsigned int got_offset
;
3029 gold_assert(gsym
->has_got_offset(got_type
));
3030 got_offset
= gsym
->got_offset(got_type
) - target
->got_size();
3034 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
3035 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
3036 got_offset
= (object
->local_got_offset(r_sym
, got_type
)
3037 - target
->got_size());
3039 if (optimized_type
== tls::TLSOPT_TO_IE
)
3041 this->tls_gd_to_ie(relinfo
, relnum
, tls_segment
, rel
, r_type
,
3042 got_offset
, view
, view_size
);
3045 else if (optimized_type
== tls::TLSOPT_NONE
)
3047 // Relocate the field with the offset of the pair of GOT
3049 Relocate_functions
<32, false>::rel32(view
, got_offset
);
3053 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
3054 _("unsupported reloc %u"),
3058 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
3059 case elfcpp::R_386_TLS_DESC_CALL
:
3060 this->local_dynamic_type_
= LOCAL_DYNAMIC_GNU
;
3061 if (optimized_type
== tls::TLSOPT_TO_LE
)
3063 if (tls_segment
== NULL
)
3065 gold_assert(parameters
->errors()->error_count() > 0
3066 || issue_undefined_symbol_error(gsym
));
3069 this->tls_desc_gd_to_le(relinfo
, relnum
, tls_segment
,
3070 rel
, r_type
, value
, view
,
3076 unsigned int got_type
= (optimized_type
== tls::TLSOPT_TO_IE
3077 ? GOT_TYPE_TLS_NOFFSET
3078 : GOT_TYPE_TLS_DESC
);
3079 unsigned int got_offset
= 0;
3080 if (r_type
== elfcpp::R_386_TLS_GOTDESC
3081 && optimized_type
== tls::TLSOPT_NONE
)
3083 // We created GOT entries in the .got.tlsdesc portion of
3084 // the .got.plt section, but the offset stored in the
3085 // symbol is the offset within .got.tlsdesc.
3086 got_offset
= (target
->got_size()
3087 + target
->got_plt_section()->data_size());
3091 gold_assert(gsym
->has_got_offset(got_type
));
3092 got_offset
+= gsym
->got_offset(got_type
) - target
->got_size();
3096 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
3097 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
3098 got_offset
+= (object
->local_got_offset(r_sym
, got_type
)
3099 - target
->got_size());
3101 if (optimized_type
== tls::TLSOPT_TO_IE
)
3103 if (tls_segment
== NULL
)
3105 gold_assert(parameters
->errors()->error_count() > 0
3106 || issue_undefined_symbol_error(gsym
));
3109 this->tls_desc_gd_to_ie(relinfo
, relnum
, tls_segment
, rel
, r_type
,
3110 got_offset
, view
, view_size
);
3113 else if (optimized_type
== tls::TLSOPT_NONE
)
3115 if (r_type
== elfcpp::R_386_TLS_GOTDESC
)
3117 // Relocate the field with the offset of the pair of GOT
3119 Relocate_functions
<32, false>::rel32(view
, got_offset
);
3124 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
3125 _("unsupported reloc %u"),
3129 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
3130 if (this->local_dynamic_type_
== LOCAL_DYNAMIC_SUN
)
3132 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
3133 _("both SUN and GNU model "
3134 "TLS relocations"));
3137 this->local_dynamic_type_
= LOCAL_DYNAMIC_GNU
;
3138 if (optimized_type
== tls::TLSOPT_TO_LE
)
3140 if (tls_segment
== NULL
)
3142 gold_assert(parameters
->errors()->error_count() > 0
3143 || issue_undefined_symbol_error(gsym
));
3146 this->tls_ld_to_le(relinfo
, relnum
, tls_segment
, rel
, r_type
,
3147 value
, view
, view_size
);
3150 else if (optimized_type
== tls::TLSOPT_NONE
)
3152 // Relocate the field with the offset of the GOT entry for
3153 // the module index.
3154 unsigned int got_offset
;
3155 got_offset
= (target
->got_mod_index_entry(NULL
, NULL
, NULL
)
3156 - target
->got_size());
3157 Relocate_functions
<32, false>::rel32(view
, got_offset
);
3160 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
3161 _("unsupported reloc %u"),
3165 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
3166 if (optimized_type
== tls::TLSOPT_TO_LE
)
3168 // This reloc can appear in debugging sections, in which
3169 // case we must not convert to local-exec. We decide what
3170 // to do based on whether the section is marked as
3171 // containing executable code. That is what the GNU linker
3173 elfcpp::Shdr
<32, false> shdr(relinfo
->data_shdr
);
3174 if ((shdr
.get_sh_flags() & elfcpp::SHF_EXECINSTR
) != 0)
3176 if (tls_segment
== NULL
)
3178 gold_assert(parameters
->errors()->error_count() > 0
3179 || issue_undefined_symbol_error(gsym
));
3182 value
-= tls_segment
->memsz();
3185 Relocate_functions
<32, false>::rel32(view
, value
);
3188 case elfcpp::R_386_TLS_IE
: // Initial-exec
3189 case elfcpp::R_386_TLS_GOTIE
:
3190 case elfcpp::R_386_TLS_IE_32
:
3191 if (optimized_type
== tls::TLSOPT_TO_LE
)
3193 if (tls_segment
== NULL
)
3195 gold_assert(parameters
->errors()->error_count() > 0
3196 || issue_undefined_symbol_error(gsym
));
3199 Target_i386::Relocate::tls_ie_to_le(relinfo
, relnum
, tls_segment
,
3200 rel
, r_type
, value
, view
,
3204 else if (optimized_type
== tls::TLSOPT_NONE
)
3206 // Relocate the field with the offset of the GOT entry for
3207 // the tp-relative offset of the symbol.
3208 unsigned int got_type
= (r_type
== elfcpp::R_386_TLS_IE_32
3209 ? GOT_TYPE_TLS_OFFSET
3210 : GOT_TYPE_TLS_NOFFSET
);
3211 unsigned int got_offset
;
3214 gold_assert(gsym
->has_got_offset(got_type
));
3215 got_offset
= gsym
->got_offset(got_type
);
3219 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
3220 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
3221 got_offset
= object
->local_got_offset(r_sym
, got_type
);
3223 // For the R_386_TLS_IE relocation, we need to apply the
3224 // absolute address of the GOT entry.
3225 if (r_type
== elfcpp::R_386_TLS_IE
)
3226 got_offset
+= target
->got_plt_section()->address();
3227 // All GOT offsets are relative to the end of the GOT.
3228 got_offset
-= target
->got_size();
3229 Relocate_functions
<32, false>::rel32(view
, got_offset
);
3232 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
3233 _("unsupported reloc %u"),
3237 case elfcpp::R_386_TLS_LE
: // Local-exec
3238 // If we're creating a shared library, a dynamic relocation will
3239 // have been created for this location, so do not apply it now.
3240 if (!parameters
->options().shared())
3242 if (tls_segment
== NULL
)
3244 gold_assert(parameters
->errors()->error_count() > 0
3245 || issue_undefined_symbol_error(gsym
));
3248 value
-= tls_segment
->memsz();
3249 Relocate_functions
<32, false>::rel32(view
, value
);
3253 case elfcpp::R_386_TLS_LE_32
:
3254 // If we're creating a shared library, a dynamic relocation will
3255 // have been created for this location, so do not apply it now.
3256 if (!parameters
->options().shared())
3258 if (tls_segment
== NULL
)
3260 gold_assert(parameters
->errors()->error_count() > 0
3261 || issue_undefined_symbol_error(gsym
));
3264 value
= tls_segment
->memsz() - value
;
3265 Relocate_functions
<32, false>::rel32(view
, value
);
3271 // Do a relocation in which we convert a TLS General-Dynamic to a
3275 Target_i386::Relocate::tls_gd_to_le(const Relocate_info
<32, false>* relinfo
,
3277 Output_segment
* tls_segment
,
3278 const elfcpp::Rel
<32, false>& rel
,
3280 elfcpp::Elf_types
<32>::Elf_Addr value
,
3281 unsigned char* view
,
3282 section_size_type view_size
)
3284 // leal foo(,%reg,1),%eax; call ___tls_get_addr
3285 // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
3286 // leal foo(%reg),%eax; call ___tls_get_addr
3287 // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
3289 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
3290 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 9);
3292 unsigned char op1
= view
[-1];
3293 unsigned char op2
= view
[-2];
3295 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3296 op2
== 0x8d || op2
== 0x04);
3297 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[4] == 0xe8);
3303 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -3);
3304 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[-3] == 0x8d);
3305 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3306 ((op1
& 0xc7) == 0x05 && op1
!= (4 << 3)));
3307 memcpy(view
- 3, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
3311 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3312 (op1
& 0xf8) == 0x80 && (op1
& 7) != 4);
3313 if (rel
.get_r_offset() + 9 < view_size
3316 // There is a trailing nop. Use the size byte subl.
3317 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
3322 // Use the five byte subl.
3323 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
3327 value
= tls_segment
->memsz() - value
;
3328 Relocate_functions
<32, false>::rel32(view
+ roff
, value
);
3330 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3332 this->skip_call_tls_get_addr_
= true;
3335 // Do a relocation in which we convert a TLS General-Dynamic to an
3339 Target_i386::Relocate::tls_gd_to_ie(const Relocate_info
<32, false>* relinfo
,
3342 const elfcpp::Rel
<32, false>& rel
,
3344 elfcpp::Elf_types
<32>::Elf_Addr value
,
3345 unsigned char* view
,
3346 section_size_type view_size
)
3348 // leal foo(,%ebx,1),%eax; call ___tls_get_addr
3349 // ==> movl %gs:0,%eax; addl foo@gotntpoff(%ebx),%eax
3350 // leal foo(%ebx),%eax; call ___tls_get_addr; nop
3351 // ==> movl %gs:0,%eax; addl foo@gotntpoff(%ebx),%eax
3353 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
3354 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 9);
3356 unsigned char op1
= view
[-1];
3357 unsigned char op2
= view
[-2];
3359 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3360 op2
== 0x8d || op2
== 0x04);
3361 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[4] == 0xe8);
3367 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -3);
3368 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[-3] == 0x8d);
3369 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3370 ((op1
& 0xc7) == 0x05 && op1
!= (4 << 3)));
3375 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 10);
3376 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3377 (op1
& 0xf8) == 0x80 && (op1
& 7) != 4);
3378 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[9] == 0x90);
3382 memcpy(view
+ roff
- 8, "\x65\xa1\0\0\0\0\x03\x83\0\0\0", 12);
3383 Relocate_functions
<32, false>::rel32(view
+ roff
, value
);
3385 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3387 this->skip_call_tls_get_addr_
= true;
3390 // Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL
3391 // General-Dynamic to a Local-Exec.
3394 Target_i386::Relocate::tls_desc_gd_to_le(
3395 const Relocate_info
<32, false>* relinfo
,
3397 Output_segment
* tls_segment
,
3398 const elfcpp::Rel
<32, false>& rel
,
3399 unsigned int r_type
,
3400 elfcpp::Elf_types
<32>::Elf_Addr value
,
3401 unsigned char* view
,
3402 section_size_type view_size
)
3404 if (r_type
== elfcpp::R_386_TLS_GOTDESC
)
3406 // leal foo@TLSDESC(%ebx), %eax
3407 // ==> leal foo@NTPOFF, %eax
3408 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
3409 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
3410 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3411 view
[-2] == 0x8d && view
[-1] == 0x83);
3413 value
-= tls_segment
->memsz();
3414 Relocate_functions
<32, false>::rel32(view
, value
);
3418 // call *foo@TLSCALL(%eax)
3420 gold_assert(r_type
== elfcpp::R_386_TLS_DESC_CALL
);
3421 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 2);
3422 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3423 view
[0] == 0xff && view
[1] == 0x10);
3429 // Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL
3430 // General-Dynamic to an Initial-Exec.
3433 Target_i386::Relocate::tls_desc_gd_to_ie(
3434 const Relocate_info
<32, false>* relinfo
,
3437 const elfcpp::Rel
<32, false>& rel
,
3438 unsigned int r_type
,
3439 elfcpp::Elf_types
<32>::Elf_Addr value
,
3440 unsigned char* view
,
3441 section_size_type view_size
)
3443 if (r_type
== elfcpp::R_386_TLS_GOTDESC
)
3445 // leal foo@TLSDESC(%ebx), %eax
3446 // ==> movl foo@GOTNTPOFF(%ebx), %eax
3447 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
3448 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
3449 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3450 view
[-2] == 0x8d && view
[-1] == 0x83);
3452 Relocate_functions
<32, false>::rel32(view
, value
);
3456 // call *foo@TLSCALL(%eax)
3458 gold_assert(r_type
== elfcpp::R_386_TLS_DESC_CALL
);
3459 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 2);
3460 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3461 view
[0] == 0xff && view
[1] == 0x10);
3467 // Do a relocation in which we convert a TLS Local-Dynamic to a
3471 Target_i386::Relocate::tls_ld_to_le(const Relocate_info
<32, false>* relinfo
,
3474 const elfcpp::Rel
<32, false>& rel
,
3476 elfcpp::Elf_types
<32>::Elf_Addr
,
3477 unsigned char* view
,
3478 section_size_type view_size
)
3480 // leal foo(%reg), %eax; call ___tls_get_addr
3481 // ==> movl %gs:0,%eax; nop; leal 0(%esi,1),%esi
3483 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
3484 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 9);
3486 // FIXME: Does this test really always pass?
3487 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3488 view
[-2] == 0x8d && view
[-1] == 0x83);
3490 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[4] == 0xe8);
3492 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x90\x8d\x74\x26\0", 11);
3494 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3496 this->skip_call_tls_get_addr_
= true;
3499 // Do a relocation in which we convert a TLS Initial-Exec to a
3503 Target_i386::Relocate::tls_ie_to_le(const Relocate_info
<32, false>* relinfo
,
3505 Output_segment
* tls_segment
,
3506 const elfcpp::Rel
<32, false>& rel
,
3507 unsigned int r_type
,
3508 elfcpp::Elf_types
<32>::Elf_Addr value
,
3509 unsigned char* view
,
3510 section_size_type view_size
)
3512 // We have to actually change the instructions, which means that we
3513 // need to examine the opcodes to figure out which instruction we
3515 if (r_type
== elfcpp::R_386_TLS_IE
)
3517 // movl %gs:XX,%eax ==> movl $YY,%eax
3518 // movl %gs:XX,%reg ==> movl $YY,%reg
3519 // addl %gs:XX,%reg ==> addl $YY,%reg
3520 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -1);
3521 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
3523 unsigned char op1
= view
[-1];
3526 // movl XX,%eax ==> movl $YY,%eax
3531 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
3533 unsigned char op2
= view
[-2];
3536 // movl XX,%reg ==> movl $YY,%reg
3537 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3538 (op1
& 0xc7) == 0x05);
3540 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
3542 else if (op2
== 0x03)
3544 // addl XX,%reg ==> addl $YY,%reg
3545 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3546 (op1
& 0xc7) == 0x05);
3548 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
3551 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), 0);
3556 // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2
3557 // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2
3558 // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2
3559 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
3560 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
3562 unsigned char op1
= view
[-1];
3563 unsigned char op2
= view
[-2];
3564 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3565 (op1
& 0xc0) == 0x80 && (op1
& 7) != 4);
3568 // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2
3570 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
3572 else if (op2
== 0x2b)
3574 // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2
3576 view
[-1] = 0xe8 | ((op1
>> 3) & 7);
3578 else if (op2
== 0x03)
3580 // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2
3582 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
3585 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), 0);
3588 value
= tls_segment
->memsz() - value
;
3589 if (r_type
== elfcpp::R_386_TLS_IE
|| r_type
== elfcpp::R_386_TLS_GOTIE
)
3592 Relocate_functions
<32, false>::rel32(view
, value
);
3595 // Relocate section data.
3598 Target_i386::relocate_section(const Relocate_info
<32, false>* relinfo
,
3599 unsigned int sh_type
,
3600 const unsigned char* prelocs
,
3602 Output_section
* output_section
,
3603 bool needs_special_offset_handling
,
3604 unsigned char* view
,
3605 elfcpp::Elf_types
<32>::Elf_Addr address
,
3606 section_size_type view_size
,
3607 const Reloc_symbol_changes
* reloc_symbol_changes
)
3609 gold_assert(sh_type
== elfcpp::SHT_REL
);
3611 gold::relocate_section
<32, false, Target_i386
, elfcpp::SHT_REL
,
3612 Target_i386::Relocate
, gold::Default_comdat_behavior
>(
3618 needs_special_offset_handling
,
3622 reloc_symbol_changes
);
3625 // Return the size of a relocation while scanning during a relocatable
3629 Target_i386::Relocatable_size_for_reloc::get_size_for_reloc(
3630 unsigned int r_type
,
3635 case elfcpp::R_386_NONE
:
3636 case elfcpp::R_386_GNU_VTINHERIT
:
3637 case elfcpp::R_386_GNU_VTENTRY
:
3638 case elfcpp::R_386_TLS_GD
: // Global-dynamic
3639 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
3640 case elfcpp::R_386_TLS_DESC_CALL
:
3641 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
3642 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
3643 case elfcpp::R_386_TLS_IE
: // Initial-exec
3644 case elfcpp::R_386_TLS_IE_32
:
3645 case elfcpp::R_386_TLS_GOTIE
:
3646 case elfcpp::R_386_TLS_LE
: // Local-exec
3647 case elfcpp::R_386_TLS_LE_32
:
3650 case elfcpp::R_386_32
:
3651 case elfcpp::R_386_PC32
:
3652 case elfcpp::R_386_GOT32
:
3653 case elfcpp::R_386_GOT32X
:
3654 case elfcpp::R_386_PLT32
:
3655 case elfcpp::R_386_GOTOFF
:
3656 case elfcpp::R_386_GOTPC
:
3659 case elfcpp::R_386_16
:
3660 case elfcpp::R_386_PC16
:
3663 case elfcpp::R_386_8
:
3664 case elfcpp::R_386_PC8
:
3667 // These are relocations which should only be seen by the
3668 // dynamic linker, and should never be seen here.
3669 case elfcpp::R_386_COPY
:
3670 case elfcpp::R_386_GLOB_DAT
:
3671 case elfcpp::R_386_JUMP_SLOT
:
3672 case elfcpp::R_386_RELATIVE
:
3673 case elfcpp::R_386_IRELATIVE
:
3674 case elfcpp::R_386_TLS_TPOFF
:
3675 case elfcpp::R_386_TLS_DTPMOD32
:
3676 case elfcpp::R_386_TLS_DTPOFF32
:
3677 case elfcpp::R_386_TLS_TPOFF32
:
3678 case elfcpp::R_386_TLS_DESC
:
3679 object
->error(_("unexpected reloc %u in object file"), r_type
);
3682 case elfcpp::R_386_32PLT
:
3683 case elfcpp::R_386_TLS_GD_32
:
3684 case elfcpp::R_386_TLS_GD_PUSH
:
3685 case elfcpp::R_386_TLS_GD_CALL
:
3686 case elfcpp::R_386_TLS_GD_POP
:
3687 case elfcpp::R_386_TLS_LDM_32
:
3688 case elfcpp::R_386_TLS_LDM_PUSH
:
3689 case elfcpp::R_386_TLS_LDM_CALL
:
3690 case elfcpp::R_386_TLS_LDM_POP
:
3691 case elfcpp::R_386_USED_BY_INTEL_200
:
3693 object
->error(_("unsupported reloc %u in object file"), r_type
);
3698 // Scan the relocs during a relocatable link.
3701 Target_i386::scan_relocatable_relocs(Symbol_table
* symtab
,
3703 Sized_relobj_file
<32, false>* object
,
3704 unsigned int data_shndx
,
3705 unsigned int sh_type
,
3706 const unsigned char* prelocs
,
3708 Output_section
* output_section
,
3709 bool needs_special_offset_handling
,
3710 size_t local_symbol_count
,
3711 const unsigned char* plocal_symbols
,
3712 Relocatable_relocs
* rr
)
3714 gold_assert(sh_type
== elfcpp::SHT_REL
);
3716 typedef gold::Default_scan_relocatable_relocs
<elfcpp::SHT_REL
,
3717 Relocatable_size_for_reloc
> Scan_relocatable_relocs
;
3719 gold::scan_relocatable_relocs
<32, false, elfcpp::SHT_REL
,
3720 Scan_relocatable_relocs
>(
3728 needs_special_offset_handling
,
3734 // Emit relocations for a section.
3737 Target_i386::relocate_relocs(
3738 const Relocate_info
<32, false>* relinfo
,
3739 unsigned int sh_type
,
3740 const unsigned char* prelocs
,
3742 Output_section
* output_section
,
3743 elfcpp::Elf_types
<32>::Elf_Off offset_in_output_section
,
3744 unsigned char* view
,
3745 elfcpp::Elf_types
<32>::Elf_Addr view_address
,
3746 section_size_type view_size
,
3747 unsigned char* reloc_view
,
3748 section_size_type reloc_view_size
)
3750 gold_assert(sh_type
== elfcpp::SHT_REL
);
3752 gold::relocate_relocs
<32, false, elfcpp::SHT_REL
>(
3757 offset_in_output_section
,
3765 // Return the value to use for a dynamic which requires special
3766 // treatment. This is how we support equality comparisons of function
3767 // pointers across shared library boundaries, as described in the
3768 // processor specific ABI supplement.
3771 Target_i386::do_dynsym_value(const Symbol
* gsym
) const
3773 gold_assert(gsym
->is_from_dynobj() && gsym
->has_plt_offset());
3774 return this->plt_address_for_global(gsym
);
3777 // Return a string used to fill a code section with nops to take up
3778 // the specified length.
3781 Target_i386::do_code_fill(section_size_type length
) const
3785 // Build a jmp instruction to skip over the bytes.
3786 unsigned char jmp
[5];
3788 elfcpp::Swap_unaligned
<32, false>::writeval(jmp
+ 1, length
- 5);
3789 return (std::string(reinterpret_cast<char*>(&jmp
[0]), 5)
3790 + std::string(length
- 5, static_cast<char>(0x90)));
3793 // Nop sequences of various lengths.
3794 const char nop1
[1] = { '\x90' }; // nop
3795 const char nop2
[2] = { '\x66', '\x90' }; // xchg %ax %ax
3796 const char nop3
[3] = { '\x8d', '\x76', '\x00' }; // leal 0(%esi),%esi
3797 const char nop4
[4] = { '\x8d', '\x74', '\x26', // leal 0(%esi,1),%esi
3799 const char nop5
[5] = { '\x90', '\x8d', '\x74', // nop
3800 '\x26', '\x00' }; // leal 0(%esi,1),%esi
3801 const char nop6
[6] = { '\x8d', '\xb6', '\x00', // leal 0L(%esi),%esi
3802 '\x00', '\x00', '\x00' };
3803 const char nop7
[7] = { '\x8d', '\xb4', '\x26', // leal 0L(%esi,1),%esi
3804 '\x00', '\x00', '\x00',
3806 const char nop8
[8] = { '\x90', '\x8d', '\xb4', // nop
3807 '\x26', '\x00', '\x00', // leal 0L(%esi,1),%esi
3809 const char nop9
[9] = { '\x89', '\xf6', '\x8d', // movl %esi,%esi
3810 '\xbc', '\x27', '\x00', // leal 0L(%edi,1),%edi
3811 '\x00', '\x00', '\x00' };
3812 const char nop10
[10] = { '\x8d', '\x76', '\x00', // leal 0(%esi),%esi
3813 '\x8d', '\xbc', '\x27', // leal 0L(%edi,1),%edi
3814 '\x00', '\x00', '\x00',
3816 const char nop11
[11] = { '\x8d', '\x74', '\x26', // leal 0(%esi,1),%esi
3817 '\x00', '\x8d', '\xbc', // leal 0L(%edi,1),%edi
3818 '\x27', '\x00', '\x00',
3820 const char nop12
[12] = { '\x8d', '\xb6', '\x00', // leal 0L(%esi),%esi
3821 '\x00', '\x00', '\x00', // leal 0L(%edi),%edi
3822 '\x8d', '\xbf', '\x00',
3823 '\x00', '\x00', '\x00' };
3824 const char nop13
[13] = { '\x8d', '\xb6', '\x00', // leal 0L(%esi),%esi
3825 '\x00', '\x00', '\x00', // leal 0L(%edi,1),%edi
3826 '\x8d', '\xbc', '\x27',
3827 '\x00', '\x00', '\x00',
3829 const char nop14
[14] = { '\x8d', '\xb4', '\x26', // leal 0L(%esi,1),%esi
3830 '\x00', '\x00', '\x00', // leal 0L(%edi,1),%edi
3831 '\x00', '\x8d', '\xbc',
3832 '\x27', '\x00', '\x00',
3834 const char nop15
[15] = { '\xeb', '\x0d', '\x90', // jmp .+15
3835 '\x90', '\x90', '\x90', // nop,nop,nop,...
3836 '\x90', '\x90', '\x90',
3837 '\x90', '\x90', '\x90',
3838 '\x90', '\x90', '\x90' };
3840 const char* nops
[16] = {
3842 nop1
, nop2
, nop3
, nop4
, nop5
, nop6
, nop7
,
3843 nop8
, nop9
, nop10
, nop11
, nop12
, nop13
, nop14
, nop15
3846 return std::string(nops
[length
], length
);
3849 // Return the value to use for the base of a DW_EH_PE_datarel offset
3850 // in an FDE. Solaris and SVR4 use DW_EH_PE_datarel because their
3851 // assembler can not write out the difference between two labels in
3852 // different sections, so instead of using a pc-relative value they
3853 // use an offset from the GOT.
3856 Target_i386::do_ehframe_datarel_base() const
3858 gold_assert(this->global_offset_table_
!= NULL
);
3859 Symbol
* sym
= this->global_offset_table_
;
3860 Sized_symbol
<32>* ssym
= static_cast<Sized_symbol
<32>*>(sym
);
3861 return ssym
->value();
3864 // Return whether SYM should be treated as a call to a non-split
3865 // function. We don't want that to be true of a call to a
3866 // get_pc_thunk function.
3869 Target_i386::do_is_call_to_non_split(const Symbol
* sym
, unsigned int) const
3871 return (sym
->type() == elfcpp::STT_FUNC
3872 && !is_prefix_of("__i686.get_pc_thunk.", sym
->name()));
3875 // FNOFFSET in section SHNDX in OBJECT is the start of a function
3876 // compiled with -fsplit-stack. The function calls non-split-stack
3877 // code. We have to change the function so that it always ensures
3878 // that it has enough stack space to run some random function.
3881 Target_i386::do_calls_non_split(Relobj
* object
, unsigned int shndx
,
3882 section_offset_type fnoffset
,
3883 section_size_type fnsize
,
3884 unsigned char* view
,
3885 section_size_type view_size
,
3887 std::string
* to
) const
3889 // The function starts with a comparison of the stack pointer and a
3890 // field in the TCB. This is followed by a jump.
3893 if (this->match_view(view
, view_size
, fnoffset
, "\x65\x3b\x25", 3)
3896 // We will call __morestack if the carry flag is set after this
3897 // comparison. We turn the comparison into an stc instruction
3899 view
[fnoffset
] = '\xf9';
3900 this->set_view_to_nop(view
, view_size
, fnoffset
+ 1, 6);
3902 // lea NN(%esp),%ecx
3903 // lea NN(%esp),%edx
3904 else if ((this->match_view(view
, view_size
, fnoffset
, "\x8d\x8c\x24", 3)
3905 || this->match_view(view
, view_size
, fnoffset
, "\x8d\x94\x24", 3))
3908 // This is loading an offset from the stack pointer for a
3909 // comparison. The offset is negative, so we decrease the
3910 // offset by the amount of space we need for the stack. This
3911 // means we will avoid calling __morestack if there happens to
3912 // be plenty of space on the stack already.
3913 unsigned char* pval
= view
+ fnoffset
+ 3;
3914 uint32_t val
= elfcpp::Swap_unaligned
<32, false>::readval(pval
);
3915 val
-= parameters
->options().split_stack_adjust_size();
3916 elfcpp::Swap_unaligned
<32, false>::writeval(pval
, val
);
3920 if (!object
->has_no_split_stack())
3921 object
->error(_("failed to match split-stack sequence at "
3922 "section %u offset %0zx"),
3923 shndx
, static_cast<size_t>(fnoffset
));
3927 // We have to change the function so that it calls
3928 // __morestack_non_split instead of __morestack. The former will
3929 // allocate additional stack space.
3930 *from
= "__morestack";
3931 *to
= "__morestack_non_split";
3934 // The selector for i386 object files. Note this is never instantiated
3935 // directly. It's only used in Target_selector_i386_nacl, below.
3937 class Target_selector_i386
: public Target_selector_freebsd
3940 Target_selector_i386()
3941 : Target_selector_freebsd(elfcpp::EM_386
, 32, false,
3942 "elf32-i386", "elf32-i386-freebsd",
3947 do_instantiate_target()
3948 { return new Target_i386(); }
3951 // NaCl variant. It uses different PLT contents.
3953 class Output_data_plt_i386_nacl
: public Output_data_plt_i386
3956 Output_data_plt_i386_nacl(Layout
* layout
,
3957 Output_data_got_plt_i386
* got_plt
,
3958 Output_data_space
* got_irelative
)
3959 : Output_data_plt_i386(layout
, plt_entry_size
, got_plt
, got_irelative
)
3963 virtual unsigned int
3964 do_get_plt_entry_size() const
3965 { return plt_entry_size
; }
3968 do_add_eh_frame(Layout
* layout
)
3970 layout
->add_eh_frame_for_plt(this, plt_eh_frame_cie
, plt_eh_frame_cie_size
,
3971 plt_eh_frame_fde
, plt_eh_frame_fde_size
);
3974 // The size of an entry in the PLT.
3975 static const int plt_entry_size
= 64;
3977 // The .eh_frame unwind information for the PLT.
3978 static const int plt_eh_frame_fde_size
= 32;
3979 static const unsigned char plt_eh_frame_fde
[plt_eh_frame_fde_size
];
3982 class Output_data_plt_i386_nacl_exec
: public Output_data_plt_i386_nacl
3985 Output_data_plt_i386_nacl_exec(Layout
* layout
,
3986 Output_data_got_plt_i386
* got_plt
,
3987 Output_data_space
* got_irelative
)
3988 : Output_data_plt_i386_nacl(layout
, got_plt
, got_irelative
)
3993 do_fill_first_plt_entry(unsigned char* pov
,
3994 elfcpp::Elf_types
<32>::Elf_Addr got_address
);
3996 virtual unsigned int
3997 do_fill_plt_entry(unsigned char* pov
,
3998 elfcpp::Elf_types
<32>::Elf_Addr got_address
,
3999 unsigned int got_offset
,
4000 unsigned int plt_offset
,
4001 unsigned int plt_rel_offset
);
4004 // The first entry in the PLT for an executable.
4005 static const unsigned char first_plt_entry
[plt_entry_size
];
4007 // Other entries in the PLT for an executable.
4008 static const unsigned char plt_entry
[plt_entry_size
];
4011 class Output_data_plt_i386_nacl_dyn
: public Output_data_plt_i386_nacl
4014 Output_data_plt_i386_nacl_dyn(Layout
* layout
,
4015 Output_data_got_plt_i386
* got_plt
,
4016 Output_data_space
* got_irelative
)
4017 : Output_data_plt_i386_nacl(layout
, got_plt
, got_irelative
)
4022 do_fill_first_plt_entry(unsigned char* pov
, elfcpp::Elf_types
<32>::Elf_Addr
);
4024 virtual unsigned int
4025 do_fill_plt_entry(unsigned char* pov
,
4026 elfcpp::Elf_types
<32>::Elf_Addr
,
4027 unsigned int got_offset
,
4028 unsigned int plt_offset
,
4029 unsigned int plt_rel_offset
);
4032 // The first entry in the PLT for a shared object.
4033 static const unsigned char first_plt_entry
[plt_entry_size
];
4035 // Other entries in the PLT for a shared object.
4036 static const unsigned char plt_entry
[plt_entry_size
];
4039 class Target_i386_nacl
: public Target_i386
4043 : Target_i386(&i386_nacl_info
)
4047 virtual Output_data_plt_i386
*
4048 do_make_data_plt(Layout
* layout
,
4049 Output_data_got_plt_i386
* got_plt
,
4050 Output_data_space
* got_irelative
,
4054 return new Output_data_plt_i386_nacl_dyn(layout
, got_plt
, got_irelative
);
4056 return new Output_data_plt_i386_nacl_exec(layout
, got_plt
, got_irelative
);
4060 do_code_fill(section_size_type length
) const;
4063 static const Target::Target_info i386_nacl_info
;
4066 const Target::Target_info
Target_i386_nacl::i386_nacl_info
=
4069 false, // is_big_endian
4070 elfcpp::EM_386
, // machine_code
4071 false, // has_make_symbol
4072 false, // has_resolve
4073 true, // has_code_fill
4074 true, // is_default_stack_executable
4075 true, // can_icf_inline_merge_sections
4077 "/lib/ld-nacl-x86-32.so.1", // dynamic_linker
4078 0x20000, // default_text_segment_address
4079 0x10000, // abi_pagesize (overridable by -z max-page-size)
4080 0x10000, // common_pagesize (overridable by -z common-page-size)
4081 true, // isolate_execinstr
4082 0x10000000, // rosegment_gap
4083 elfcpp::SHN_UNDEF
, // small_common_shndx
4084 elfcpp::SHN_UNDEF
, // large_common_shndx
4085 0, // small_common_section_flags
4086 0, // large_common_section_flags
4087 NULL
, // attributes_section
4088 NULL
, // attributes_vendor
4089 "_start", // entry_symbol_name
4090 32, // hash_entry_size
4093 #define NACLMASK 0xe0 // 32-byte alignment mask
4096 Output_data_plt_i386_nacl_exec::first_plt_entry
[plt_entry_size
] =
4098 0xff, 0x35, // pushl contents of memory address
4099 0, 0, 0, 0, // replaced with address of .got + 4
4100 0x8b, 0x0d, // movl contents of address, %ecx
4101 0, 0, 0, 0, // replaced with address of .got + 8
4102 0x83, 0xe1, NACLMASK
, // andl $NACLMASK, %ecx
4103 0xff, 0xe1, // jmp *%ecx
4104 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4105 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4106 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4107 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4108 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4109 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4110 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4111 0x90, 0x90, 0x90, 0x90, 0x90
4115 Output_data_plt_i386_nacl_exec::do_fill_first_plt_entry(
4117 elfcpp::Elf_types
<32>::Elf_Addr got_address
)
4119 memcpy(pov
, first_plt_entry
, plt_entry_size
);
4120 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2, got_address
+ 4);
4121 elfcpp::Swap
<32, false>::writeval(pov
+ 8, got_address
+ 8);
4124 // The first entry in the PLT for a shared object.
4127 Output_data_plt_i386_nacl_dyn::first_plt_entry
[plt_entry_size
] =
4129 0xff, 0xb3, 4, 0, 0, 0, // pushl 4(%ebx)
4130 0x8b, 0x4b, 0x08, // mov 0x8(%ebx), %ecx
4131 0x83, 0xe1, NACLMASK
, // andl $NACLMASK, %ecx
4132 0xff, 0xe1, // jmp *%ecx
4133 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4134 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4135 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4136 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4137 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4138 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4139 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4140 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4141 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4142 0x90, 0x90, 0x90, 0x90, 0x90 // nops
4146 Output_data_plt_i386_nacl_dyn::do_fill_first_plt_entry(
4148 elfcpp::Elf_types
<32>::Elf_Addr
)
4150 memcpy(pov
, first_plt_entry
, plt_entry_size
);
4153 // Subsequent entries in the PLT for an executable.
4156 Output_data_plt_i386_nacl_exec::plt_entry
[plt_entry_size
] =
4158 0x8b, 0x0d, // movl contents of address, %ecx */
4159 0, 0, 0, 0, // replaced with address of symbol in .got
4160 0x83, 0xe1, NACLMASK
, // andl $NACLMASK, %ecx
4161 0xff, 0xe1, // jmp *%ecx
4163 // Pad to the next 32-byte boundary with nop instructions.
4165 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4166 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4168 // Lazy GOT entries point here (32-byte aligned).
4169 0x68, // pushl immediate
4170 0, 0, 0, 0, // replaced with offset into relocation table
4171 0xe9, // jmp relative
4172 0, 0, 0, 0, // replaced with offset to start of .plt
4174 // Pad to the next 32-byte boundary with nop instructions.
4175 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4176 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4181 Output_data_plt_i386_nacl_exec::do_fill_plt_entry(
4183 elfcpp::Elf_types
<32>::Elf_Addr got_address
,
4184 unsigned int got_offset
,
4185 unsigned int plt_offset
,
4186 unsigned int plt_rel_offset
)
4188 memcpy(pov
, plt_entry
, plt_entry_size
);
4189 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
4190 got_address
+ got_offset
);
4191 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 33, plt_rel_offset
);
4192 elfcpp::Swap
<32, false>::writeval(pov
+ 38, - (plt_offset
+ 38 + 4));
4196 // Subsequent entries in the PLT for a shared object.
4199 Output_data_plt_i386_nacl_dyn::plt_entry
[plt_entry_size
] =
4201 0x8b, 0x8b, // movl offset(%ebx), %ecx
4202 0, 0, 0, 0, // replaced with offset of symbol in .got
4203 0x83, 0xe1, 0xe0, // andl $NACLMASK, %ecx
4204 0xff, 0xe1, // jmp *%ecx
4206 // Pad to the next 32-byte boundary with nop instructions.
4208 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4209 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4211 // Lazy GOT entries point here (32-byte aligned).
4212 0x68, // pushl immediate
4213 0, 0, 0, 0, // replaced with offset into relocation table.
4214 0xe9, // jmp relative
4215 0, 0, 0, 0, // replaced with offset to start of .plt.
4217 // Pad to the next 32-byte boundary with nop instructions.
4218 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4219 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4224 Output_data_plt_i386_nacl_dyn::do_fill_plt_entry(
4226 elfcpp::Elf_types
<32>::Elf_Addr
,
4227 unsigned int got_offset
,
4228 unsigned int plt_offset
,
4229 unsigned int plt_rel_offset
)
4231 memcpy(pov
, plt_entry
, plt_entry_size
);
4232 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2, got_offset
);
4233 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 33, plt_rel_offset
);
4234 elfcpp::Swap
<32, false>::writeval(pov
+ 38, - (plt_offset
+ 38 + 4));
4239 Output_data_plt_i386_nacl::plt_eh_frame_fde
[plt_eh_frame_fde_size
] =
4241 0, 0, 0, 0, // Replaced with offset to .plt.
4242 0, 0, 0, 0, // Replaced with size of .plt.
4243 0, // Augmentation size.
4244 elfcpp::DW_CFA_def_cfa_offset
, 8, // DW_CFA_def_cfa_offset: 8.
4245 elfcpp::DW_CFA_advance_loc
+ 6, // Advance 6 to __PLT__ + 6.
4246 elfcpp::DW_CFA_def_cfa_offset
, 12, // DW_CFA_def_cfa_offset: 12.
4247 elfcpp::DW_CFA_advance_loc
+ 58, // Advance 58 to __PLT__ + 64.
4248 elfcpp::DW_CFA_def_cfa_expression
, // DW_CFA_def_cfa_expression.
4249 13, // Block length.
4250 elfcpp::DW_OP_breg4
, 4, // Push %esp + 4.
4251 elfcpp::DW_OP_breg8
, 0, // Push %eip.
4252 elfcpp::DW_OP_const1u
, 63, // Push 0x3f.
4253 elfcpp::DW_OP_and
, // & (%eip & 0x3f).
4254 elfcpp::DW_OP_const1u
, 37, // Push 0x25.
4255 elfcpp::DW_OP_ge
, // >= ((%eip & 0x3f) >= 0x25)
4256 elfcpp::DW_OP_lit2
, // Push 2.
4257 elfcpp::DW_OP_shl
, // << (((%eip & 0x3f) >= 0x25) << 2)
4258 elfcpp::DW_OP_plus
, // + ((((%eip&0x3f)>=0x25)<<2)+%esp+4
4259 elfcpp::DW_CFA_nop
, // Align to 32 bytes.
4263 // Return a string used to fill a code section with nops.
4264 // For NaCl, long NOPs are only valid if they do not cross
4265 // bundle alignment boundaries, so keep it simple with one-byte NOPs.
4267 Target_i386_nacl::do_code_fill(section_size_type length
) const
4269 return std::string(length
, static_cast<char>(0x90));
4272 // The selector for i386-nacl object files.
4274 class Target_selector_i386_nacl
4275 : public Target_selector_nacl
<Target_selector_i386
, Target_i386_nacl
>
4278 Target_selector_i386_nacl()
4279 : Target_selector_nacl
<Target_selector_i386
,
4280 Target_i386_nacl
>("x86-32",
4286 Target_selector_i386_nacl target_selector_i386
;
4288 // IAMCU variant. It uses EM_IAMCU, not EM_386.
4290 class Target_iamcu
: public Target_i386
4294 : Target_i386(&iamcu_info
)
4298 // Information about this specific target which we pass to the
4299 // general Target structure.
4300 static const Target::Target_info iamcu_info
;
4303 const Target::Target_info
Target_iamcu::iamcu_info
=
4306 false, // is_big_endian
4307 elfcpp::EM_IAMCU
, // machine_code
4308 false, // has_make_symbol
4309 false, // has_resolve
4310 true, // has_code_fill
4311 true, // is_default_stack_executable
4312 true, // can_icf_inline_merge_sections
4314 "/usr/lib/libc.so.1", // dynamic_linker
4315 0x08048000, // default_text_segment_address
4316 0x1000, // abi_pagesize (overridable by -z max-page-size)
4317 0x1000, // common_pagesize (overridable by -z common-page-size)
4318 false, // isolate_execinstr
4320 elfcpp::SHN_UNDEF
, // small_common_shndx
4321 elfcpp::SHN_UNDEF
, // large_common_shndx
4322 0, // small_common_section_flags
4323 0, // large_common_section_flags
4324 NULL
, // attributes_section
4325 NULL
, // attributes_vendor
4326 "_start", // entry_symbol_name
4327 32, // hash_entry_size
4330 class Target_selector_iamcu
: public Target_selector
4333 Target_selector_iamcu()
4334 : Target_selector(elfcpp::EM_IAMCU
, 32, false, "elf32-iamcu",
4339 do_instantiate_target()
4340 { return new Target_iamcu(); }
4343 Target_selector_iamcu target_selector_iamcu
;
4345 } // End anonymous namespace.