1 // i386.cc -- i386 target support for gold.
3 // Copyright (C) 2006-2023 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 // Scan the relocs for --emit-relocs.
434 emit_relocs_scan(Symbol_table
* symtab
,
436 Sized_relobj_file
<32, false>* object
,
437 unsigned int data_shndx
,
438 unsigned int sh_type
,
439 const unsigned char* prelocs
,
441 Output_section
* output_section
,
442 bool needs_special_offset_handling
,
443 size_t local_symbol_count
,
444 const unsigned char* plocal_syms
,
445 Relocatable_relocs
* rr
);
447 // Emit relocations for a section.
449 relocate_relocs(const Relocate_info
<32, false>*,
450 unsigned int sh_type
,
451 const unsigned char* prelocs
,
453 Output_section
* output_section
,
454 elfcpp::Elf_types
<32>::Elf_Off offset_in_output_section
,
456 elfcpp::Elf_types
<32>::Elf_Addr view_address
,
457 section_size_type view_size
,
458 unsigned char* reloc_view
,
459 section_size_type reloc_view_size
);
461 // Return a string used to fill a code section with nops.
463 do_code_fill(section_size_type length
) const;
465 // Return whether SYM is defined by the ABI.
467 do_is_defined_by_abi(const Symbol
* sym
) const
468 { return strcmp(sym
->name(), "___tls_get_addr") == 0; }
470 // Return whether a symbol name implies a local label. The UnixWare
471 // 2.1 cc generates temporary symbols that start with .X, so we
472 // recognize them here. FIXME: do other SVR4 compilers also use .X?.
473 // If so, we should move the .X recognition into
474 // Target::do_is_local_label_name.
476 do_is_local_label_name(const char* name
) const
478 if (name
[0] == '.' && name
[1] == 'X')
480 return Target::do_is_local_label_name(name
);
483 // Return the PLT address to use for a global symbol.
485 do_plt_address_for_global(const Symbol
* gsym
) const
486 { return this->plt_section()->address_for_global(gsym
); }
489 do_plt_address_for_local(const Relobj
* relobj
, unsigned int symndx
) const
490 { return this->plt_section()->address_for_local(relobj
, symndx
); }
492 // We can tell whether we take the address of a function.
494 do_can_check_for_function_pointers() const
497 // Return the base for a DW_EH_PE_datarel encoding.
499 do_ehframe_datarel_base() const;
501 // Return whether SYM is call to a non-split function.
503 do_is_call_to_non_split(const Symbol
* sym
, const unsigned char*,
504 const unsigned char*, section_size_type
) const;
506 // Adjust -fsplit-stack code which calls non-split-stack code.
508 do_calls_non_split(Relobj
* object
, unsigned int shndx
,
509 section_offset_type fnoffset
, section_size_type fnsize
,
510 const unsigned char* prelocs
, size_t reloc_count
,
511 unsigned char* view
, section_size_type view_size
,
512 std::string
* from
, std::string
* to
) const;
514 // Return the size of the GOT section.
518 gold_assert(this->got_
!= NULL
);
519 return this->got_
->data_size();
522 // Return the number of entries in the GOT.
524 got_entry_count() const
526 if (this->got_
== NULL
)
528 return this->got_size() / 4;
531 // Return the number of entries in the PLT.
533 plt_entry_count() const;
535 // Return the offset of the first non-reserved PLT entry.
537 first_plt_entry_offset() const;
539 // Return the size of each PLT entry.
541 plt_entry_size() const;
544 // Instantiate the plt_ member.
545 // This chooses the right PLT flavor for an executable or a shared object.
546 Output_data_plt_i386
*
547 make_data_plt(Layout
* layout
,
548 Output_data_got_plt_i386
* got_plt
,
549 Output_data_space
* got_irelative
,
551 { return this->do_make_data_plt(layout
, got_plt
, got_irelative
, dyn
); }
553 virtual Output_data_plt_i386
*
554 do_make_data_plt(Layout
* layout
,
555 Output_data_got_plt_i386
* got_plt
,
556 Output_data_space
* got_irelative
,
560 return new Output_data_plt_i386_dyn(layout
, got_plt
, got_irelative
);
562 return new Output_data_plt_i386_exec(layout
, got_plt
, got_irelative
);
566 // The class which scans relocations.
571 get_reference_flags(unsigned int r_type
);
574 local(Symbol_table
* symtab
, Layout
* layout
, Target_i386
* target
,
575 Sized_relobj_file
<32, false>* object
,
576 unsigned int data_shndx
,
577 Output_section
* output_section
,
578 const elfcpp::Rel
<32, false>& reloc
, unsigned int r_type
,
579 const elfcpp::Sym
<32, false>& lsym
,
583 global(Symbol_table
* symtab
, Layout
* layout
, Target_i386
* target
,
584 Sized_relobj_file
<32, false>* object
,
585 unsigned int data_shndx
,
586 Output_section
* output_section
,
587 const elfcpp::Rel
<32, false>& reloc
, unsigned int r_type
,
591 local_reloc_may_be_function_pointer(Symbol_table
* symtab
, Layout
* layout
,
593 Sized_relobj_file
<32, false>* object
,
594 unsigned int data_shndx
,
595 Output_section
* output_section
,
596 const elfcpp::Rel
<32, false>& reloc
,
598 const elfcpp::Sym
<32, false>& lsym
);
601 global_reloc_may_be_function_pointer(Symbol_table
* symtab
, Layout
* layout
,
603 Sized_relobj_file
<32, false>* object
,
604 unsigned int data_shndx
,
605 Output_section
* output_section
,
606 const elfcpp::Rel
<32, false>& reloc
,
611 possible_function_pointer_reloc(unsigned int r_type
);
614 reloc_needs_plt_for_ifunc(Sized_relobj_file
<32, false>*,
615 unsigned int r_type
);
618 unsupported_reloc_local(Sized_relobj_file
<32, false>*, unsigned int r_type
);
621 unsupported_reloc_global(Sized_relobj_file
<32, false>*, unsigned int r_type
,
625 // The class which implements relocation.
630 : skip_call_tls_get_addr_(false),
631 local_dynamic_type_(LOCAL_DYNAMIC_NONE
)
636 if (this->skip_call_tls_get_addr_
)
638 // FIXME: This needs to specify the location somehow.
639 gold_error(_("missing expected TLS relocation"));
643 // Return whether the static relocation needs to be applied.
645 should_apply_static_reloc(const Sized_symbol
<32>* gsym
,
648 Output_section
* output_section
);
650 // Do a relocation. Return false if the caller should not issue
651 // any warnings about this relocation.
653 relocate(const Relocate_info
<32, false>*, unsigned int,
654 Target_i386
*, Output_section
*, size_t, const unsigned char*,
655 const Sized_symbol
<32>*, const Symbol_value
<32>*,
656 unsigned char*, elfcpp::Elf_types
<32>::Elf_Addr
,
660 // Do a TLS relocation.
662 relocate_tls(const Relocate_info
<32, false>*, Target_i386
* target
,
663 size_t relnum
, const elfcpp::Rel
<32, false>&,
664 unsigned int r_type
, const Sized_symbol
<32>*,
665 const Symbol_value
<32>*,
666 unsigned char*, elfcpp::Elf_types
<32>::Elf_Addr
,
669 // Do a TLS General-Dynamic to Initial-Exec transition.
671 tls_gd_to_ie(const Relocate_info
<32, false>*, size_t relnum
,
672 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
673 elfcpp::Elf_types
<32>::Elf_Addr value
,
675 section_size_type view_size
);
677 // Do a TLS General-Dynamic to Local-Exec transition.
679 tls_gd_to_le(const Relocate_info
<32, false>*, size_t relnum
,
680 Output_segment
* tls_segment
,
681 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
682 elfcpp::Elf_types
<32>::Elf_Addr value
,
684 section_size_type view_size
);
686 // Do a TLS_GOTDESC or TLS_DESC_CALL General-Dynamic to Initial-Exec
689 tls_desc_gd_to_ie(const Relocate_info
<32, false>*, size_t relnum
,
690 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
691 elfcpp::Elf_types
<32>::Elf_Addr value
,
693 section_size_type view_size
);
695 // Do a TLS_GOTDESC or TLS_DESC_CALL General-Dynamic to Local-Exec
698 tls_desc_gd_to_le(const Relocate_info
<32, false>*, size_t relnum
,
699 Output_segment
* tls_segment
,
700 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
701 elfcpp::Elf_types
<32>::Elf_Addr value
,
703 section_size_type view_size
);
705 // Do a TLS Local-Dynamic to Local-Exec transition.
707 tls_ld_to_le(const Relocate_info
<32, false>*, size_t relnum
,
708 Output_segment
* tls_segment
,
709 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
710 elfcpp::Elf_types
<32>::Elf_Addr value
,
712 section_size_type view_size
);
714 // Do a TLS Initial-Exec to Local-Exec transition.
716 tls_ie_to_le(const Relocate_info
<32, false>*, size_t relnum
,
717 Output_segment
* tls_segment
,
718 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
719 elfcpp::Elf_types
<32>::Elf_Addr value
,
721 section_size_type view_size
);
723 // We need to keep track of which type of local dynamic relocation
724 // we have seen, so that we can optimize R_386_TLS_LDO_32 correctly.
725 enum Local_dynamic_type
732 // This is set if we should skip the next reloc, which should be a
733 // PLT32 reloc against ___tls_get_addr.
734 bool skip_call_tls_get_addr_
;
735 // The type of local dynamic relocation we have seen in the section
736 // being relocated, if any.
737 Local_dynamic_type local_dynamic_type_
;
740 // A class for inquiring about properties of a relocation,
741 // used while scanning relocs during a relocatable link and
742 // garbage collection.
743 class Classify_reloc
:
744 public gold::Default_classify_reloc
<elfcpp::SHT_REL
, 32, false>
747 typedef Reloc_types
<elfcpp::SHT_REL
, 32, false>::Reloc Reltype
;
749 // Return the explicit addend of the relocation (return 0 for SHT_REL).
750 static elfcpp::Elf_types
<32>::Elf_Swxword
751 get_r_addend(const Reltype
*)
754 // Return the size of the addend of the relocation (only used for SHT_REL).
756 get_size_for_reloc(unsigned int, Relobj
*);
759 // Adjust TLS relocation type based on the options and whether this
760 // is a local symbol.
761 static tls::Tls_optimization
762 optimize_tls_reloc(bool is_final
, int r_type
);
764 // Check if relocation against this symbol is a candidate for
766 // mov foo@GOT(%reg), %reg
768 // lea foo@GOTOFF(%reg), %reg.
770 can_convert_mov_to_lea(const Symbol
* gsym
)
772 gold_assert(gsym
!= NULL
);
773 return (gsym
->type() != elfcpp::STT_GNU_IFUNC
774 && !gsym
->is_undefined ()
775 && !gsym
->is_from_dynobj()
776 && !gsym
->is_preemptible()
777 && (!parameters
->options().shared()
778 || (gsym
->visibility() != elfcpp::STV_DEFAULT
779 && gsym
->visibility() != elfcpp::STV_PROTECTED
)
780 || parameters
->options().Bsymbolic())
781 && strcmp(gsym
->name(), "_DYNAMIC") != 0);
784 // Get the GOT section, creating it if necessary.
785 Output_data_got
<32, false>*
786 got_section(Symbol_table
*, Layout
*);
788 // Get the GOT PLT section.
789 Output_data_got_plt_i386
*
790 got_plt_section() const
792 gold_assert(this->got_plt_
!= NULL
);
793 return this->got_plt_
;
796 // Get the GOT section for TLSDESC entries.
797 Output_data_got
<32, false>*
798 got_tlsdesc_section() const
800 gold_assert(this->got_tlsdesc_
!= NULL
);
801 return this->got_tlsdesc_
;
804 // Create the PLT section.
806 make_plt_section(Symbol_table
* symtab
, Layout
* layout
);
808 // Create a PLT entry for a global symbol.
810 make_plt_entry(Symbol_table
*, Layout
*, Symbol
*);
812 // Create a PLT entry for a local STT_GNU_IFUNC symbol.
814 make_local_ifunc_plt_entry(Symbol_table
*, Layout
*,
815 Sized_relobj_file
<32, false>* relobj
,
816 unsigned int local_sym_index
);
818 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
820 define_tls_base_symbol(Symbol_table
*, Layout
*);
822 // Create a GOT entry for the TLS module index.
824 got_mod_index_entry(Symbol_table
* symtab
, Layout
* layout
,
825 Sized_relobj_file
<32, false>* object
);
827 // Get the PLT section.
828 Output_data_plt_i386
*
831 gold_assert(this->plt_
!= NULL
);
835 // Get the dynamic reloc section, creating it if necessary.
837 rel_dyn_section(Layout
*);
839 // Get the section to use for TLS_DESC relocations.
841 rel_tls_desc_section(Layout
*) const;
843 // Get the section to use for IRELATIVE relocations.
845 rel_irelative_section(Layout
*);
847 // Add a potential copy relocation.
849 copy_reloc(Symbol_table
* symtab
, Layout
* layout
,
850 Sized_relobj_file
<32, false>* object
,
851 unsigned int shndx
, Output_section
* output_section
,
852 Symbol
* sym
, const elfcpp::Rel
<32, false>& reloc
)
854 unsigned int r_type
= elfcpp::elf_r_type
<32>(reloc
.get_r_info());
855 this->copy_relocs_
.copy_reloc(symtab
, layout
,
856 symtab
->get_sized_symbol
<32>(sym
),
857 object
, shndx
, output_section
,
858 r_type
, reloc
.get_r_offset(), 0,
859 this->rel_dyn_section(layout
));
862 // Information about this specific target which we pass to the
863 // general Target structure.
864 static const Target::Target_info i386_info
;
866 // The types of GOT entries needed for this platform.
867 // These values are exposed to the ABI in an incremental link.
868 // Do not renumber existing values without changing the version
869 // number of the .gnu_incremental_inputs section.
872 GOT_TYPE_STANDARD
= 0, // GOT entry for a regular symbol
873 GOT_TYPE_TLS_NOFFSET
= 1, // GOT entry for negative TLS offset
874 GOT_TYPE_TLS_OFFSET
= 2, // GOT entry for positive TLS offset
875 GOT_TYPE_TLS_PAIR
= 3, // GOT entry for TLS module/offset pair
876 GOT_TYPE_TLS_DESC
= 4 // GOT entry for TLS_DESC pair
880 Output_data_got
<32, false>* got_
;
882 Output_data_plt_i386
* plt_
;
883 // The GOT PLT section.
884 Output_data_got_plt_i386
* got_plt_
;
885 // The GOT section for IRELATIVE relocations.
886 Output_data_space
* got_irelative_
;
887 // The GOT section for TLSDESC relocations.
888 Output_data_got
<32, false>* got_tlsdesc_
;
889 // The _GLOBAL_OFFSET_TABLE_ symbol.
890 Symbol
* global_offset_table_
;
891 // The dynamic reloc section.
892 Reloc_section
* rel_dyn_
;
893 // The section to use for IRELATIVE relocs.
894 Reloc_section
* rel_irelative_
;
895 // Relocs saved to avoid a COPY reloc.
896 Copy_relocs
<elfcpp::SHT_REL
, 32, false> copy_relocs_
;
897 // Offset of the GOT entry for the TLS module index.
898 unsigned int got_mod_index_offset_
;
899 // True if the _TLS_MODULE_BASE_ symbol has been defined.
900 bool tls_base_symbol_defined_
;
903 const Target::Target_info
Target_i386::i386_info
=
906 false, // is_big_endian
907 elfcpp::EM_386
, // machine_code
908 false, // has_make_symbol
909 false, // has_resolve
910 true, // has_code_fill
911 true, // is_default_stack_executable
912 true, // can_icf_inline_merge_sections
914 "/usr/lib/libc.so.1", // dynamic_linker
915 0x08048000, // default_text_segment_address
916 0x1000, // abi_pagesize (overridable by -z max-page-size)
917 0x1000, // common_pagesize (overridable by -z common-page-size)
918 false, // isolate_execinstr
920 elfcpp::SHN_UNDEF
, // small_common_shndx
921 elfcpp::SHN_UNDEF
, // large_common_shndx
922 0, // small_common_section_flags
923 0, // large_common_section_flags
924 NULL
, // attributes_section
925 NULL
, // attributes_vendor
926 "_start", // entry_symbol_name
927 32, // hash_entry_size
928 elfcpp::SHT_PROGBITS
, // unwind_section_type
931 // Get the GOT section, creating it if necessary.
933 Output_data_got
<32, false>*
934 Target_i386::got_section(Symbol_table
* symtab
, Layout
* layout
)
936 if (this->got_
== NULL
)
938 gold_assert(symtab
!= NULL
&& layout
!= NULL
);
940 this->got_
= new Output_data_got
<32, false>();
942 // When using -z now, we can treat .got.plt as a relro section.
943 // Without -z now, it is modified after program startup by lazy
945 bool is_got_plt_relro
= parameters
->options().now();
946 Output_section_order got_order
= (is_got_plt_relro
949 Output_section_order got_plt_order
= (is_got_plt_relro
951 : ORDER_NON_RELRO_FIRST
);
953 layout
->add_output_section_data(".got", elfcpp::SHT_PROGBITS
,
955 | elfcpp::SHF_WRITE
),
956 this->got_
, got_order
, true);
958 this->got_plt_
= new Output_data_got_plt_i386(layout
);
959 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
961 | elfcpp::SHF_WRITE
),
962 this->got_plt_
, got_plt_order
,
965 // The first three entries are reserved.
966 this->got_plt_
->set_current_data_size(3 * 4);
968 if (!is_got_plt_relro
)
970 // Those bytes can go into the relro segment.
971 layout
->increase_relro(3 * 4);
974 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
975 this->global_offset_table_
=
976 symtab
->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL
,
977 Symbol_table::PREDEFINED
,
979 0, 0, elfcpp::STT_OBJECT
,
981 elfcpp::STV_HIDDEN
, 0,
984 // If there are any IRELATIVE relocations, they get GOT entries
985 // in .got.plt after the jump slot relocations.
986 this->got_irelative_
= new Output_data_space(4, "** GOT IRELATIVE PLT");
987 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
989 | elfcpp::SHF_WRITE
),
990 this->got_irelative_
,
991 got_plt_order
, is_got_plt_relro
);
993 // If there are any TLSDESC relocations, they get GOT entries in
994 // .got.plt after the jump slot entries.
995 this->got_tlsdesc_
= new Output_data_got
<32, false>();
996 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
998 | elfcpp::SHF_WRITE
),
1000 got_plt_order
, is_got_plt_relro
);
1006 // Get the dynamic reloc section, creating it if necessary.
1008 Target_i386::Reloc_section
*
1009 Target_i386::rel_dyn_section(Layout
* layout
)
1011 if (this->rel_dyn_
== NULL
)
1013 gold_assert(layout
!= NULL
);
1014 this->rel_dyn_
= new Reloc_section(parameters
->options().combreloc());
1015 layout
->add_output_section_data(".rel.dyn", elfcpp::SHT_REL
,
1016 elfcpp::SHF_ALLOC
, this->rel_dyn_
,
1017 ORDER_DYNAMIC_RELOCS
, false);
1019 return this->rel_dyn_
;
1022 // Get the section to use for IRELATIVE relocs, creating it if
1023 // necessary. These go in .rel.dyn, but only after all other dynamic
1024 // relocations. They need to follow the other dynamic relocations so
1025 // that they can refer to global variables initialized by those
1028 Target_i386::Reloc_section
*
1029 Target_i386::rel_irelative_section(Layout
* layout
)
1031 if (this->rel_irelative_
== NULL
)
1033 // Make sure we have already create the dynamic reloc section.
1034 this->rel_dyn_section(layout
);
1035 this->rel_irelative_
= new Reloc_section(false);
1036 layout
->add_output_section_data(".rel.dyn", elfcpp::SHT_REL
,
1037 elfcpp::SHF_ALLOC
, this->rel_irelative_
,
1038 ORDER_DYNAMIC_RELOCS
, false);
1039 gold_assert(this->rel_dyn_
->output_section()
1040 == this->rel_irelative_
->output_section());
1042 return this->rel_irelative_
;
1045 // Write the first three reserved words of the .got.plt section.
1046 // The remainder of the section is written while writing the PLT
1047 // in Output_data_plt_i386::do_write.
1050 Output_data_got_plt_i386::do_write(Output_file
* of
)
1052 // The first entry in the GOT is the address of the .dynamic section
1053 // aka the PT_DYNAMIC segment. The next two entries are reserved.
1054 // We saved space for them when we created the section in
1055 // Target_i386::got_section.
1056 const off_t got_file_offset
= this->offset();
1057 gold_assert(this->data_size() >= 12);
1058 unsigned char* const got_view
= of
->get_output_view(got_file_offset
, 12);
1059 Output_section
* dynamic
= this->layout_
->dynamic_section();
1060 uint32_t dynamic_addr
= dynamic
== NULL
? 0 : dynamic
->address();
1061 elfcpp::Swap
<32, false>::writeval(got_view
, dynamic_addr
);
1062 memset(got_view
+ 4, 0, 8);
1063 of
->write_output_view(got_file_offset
, 12, got_view
);
1066 // Create the PLT section. The ordinary .got section is an argument,
1067 // since we need to refer to the start. We also create our own .got
1068 // section just for PLT entries.
1070 Output_data_plt_i386::Output_data_plt_i386(Layout
* layout
,
1072 Output_data_got_plt_i386
* got_plt
,
1073 Output_data_space
* got_irelative
)
1074 : Output_section_data(addralign
),
1075 tls_desc_rel_(NULL
), irelative_rel_(NULL
), got_plt_(got_plt
),
1076 got_irelative_(got_irelative
), count_(0), irelative_count_(0),
1077 global_ifuncs_(), local_ifuncs_()
1079 this->rel_
= new Reloc_section(false);
1080 layout
->add_output_section_data(".rel.plt", elfcpp::SHT_REL
,
1081 elfcpp::SHF_ALLOC
, this->rel_
,
1082 ORDER_DYNAMIC_PLT_RELOCS
, false);
1086 Output_data_plt_i386::do_adjust_output_section(Output_section
* os
)
1088 // UnixWare sets the entsize of .plt to 4, and so does the old GNU
1089 // linker, and so do we.
1093 // Add an entry to the PLT.
1096 Output_data_plt_i386::add_entry(Symbol_table
* symtab
, Layout
* layout
,
1099 gold_assert(!gsym
->has_plt_offset());
1101 // Every PLT entry needs a reloc.
1102 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
1103 && gsym
->can_use_relative_reloc(false))
1105 gsym
->set_plt_offset(this->irelative_count_
* this->get_plt_entry_size());
1106 ++this->irelative_count_
;
1107 section_offset_type got_offset
=
1108 this->got_irelative_
->current_data_size();
1109 this->got_irelative_
->set_current_data_size(got_offset
+ 4);
1110 Reloc_section
* rel
= this->rel_irelative(symtab
, layout
);
1111 rel
->add_symbolless_global_addend(gsym
, elfcpp::R_386_IRELATIVE
,
1112 this->got_irelative_
, got_offset
);
1113 struct Global_ifunc gi
;
1115 gi
.got_offset
= got_offset
;
1116 this->global_ifuncs_
.push_back(gi
);
1120 // When setting the PLT offset we skip the initial reserved PLT
1122 gsym
->set_plt_offset((this->count_
+ 1) * this->get_plt_entry_size());
1126 section_offset_type got_offset
= this->got_plt_
->current_data_size();
1128 // Every PLT entry needs a GOT entry which points back to the
1129 // PLT entry (this will be changed by the dynamic linker,
1130 // normally lazily when the function is called).
1131 this->got_plt_
->set_current_data_size(got_offset
+ 4);
1133 gsym
->set_needs_dynsym_entry();
1134 this->rel_
->add_global(gsym
, elfcpp::R_386_JUMP_SLOT
, this->got_plt_
,
1138 // Note that we don't need to save the symbol. The contents of the
1139 // PLT are independent of which symbols are used. The symbols only
1140 // appear in the relocations.
1143 // Add an entry to the PLT for a local STT_GNU_IFUNC symbol. Return
1147 Output_data_plt_i386::add_local_ifunc_entry(
1148 Symbol_table
* symtab
,
1150 Sized_relobj_file
<32, false>* relobj
,
1151 unsigned int local_sym_index
)
1153 unsigned int plt_offset
= this->irelative_count_
* this->get_plt_entry_size();
1154 ++this->irelative_count_
;
1156 section_offset_type got_offset
= this->got_irelative_
->current_data_size();
1158 // Every PLT entry needs a GOT entry which points back to the PLT
1160 this->got_irelative_
->set_current_data_size(got_offset
+ 4);
1162 // Every PLT entry needs a reloc.
1163 Reloc_section
* rel
= this->rel_irelative(symtab
, layout
);
1164 rel
->add_symbolless_local_addend(relobj
, local_sym_index
,
1165 elfcpp::R_386_IRELATIVE
,
1166 this->got_irelative_
, got_offset
);
1168 struct Local_ifunc li
;
1170 li
.local_sym_index
= local_sym_index
;
1171 li
.got_offset
= got_offset
;
1172 this->local_ifuncs_
.push_back(li
);
1177 // Return where the TLS_DESC relocations should go, creating it if
1178 // necessary. These follow the JUMP_SLOT relocations.
1180 Output_data_plt_i386::Reloc_section
*
1181 Output_data_plt_i386::rel_tls_desc(Layout
* layout
)
1183 if (this->tls_desc_rel_
== NULL
)
1185 this->tls_desc_rel_
= new Reloc_section(false);
1186 layout
->add_output_section_data(".rel.plt", elfcpp::SHT_REL
,
1187 elfcpp::SHF_ALLOC
, this->tls_desc_rel_
,
1188 ORDER_DYNAMIC_PLT_RELOCS
, false);
1189 gold_assert(this->tls_desc_rel_
->output_section()
1190 == this->rel_
->output_section());
1192 return this->tls_desc_rel_
;
1195 // Return where the IRELATIVE relocations should go in the PLT. These
1196 // follow the JUMP_SLOT and TLS_DESC relocations.
1198 Output_data_plt_i386::Reloc_section
*
1199 Output_data_plt_i386::rel_irelative(Symbol_table
* symtab
, Layout
* layout
)
1201 if (this->irelative_rel_
== NULL
)
1203 // Make sure we have a place for the TLS_DESC relocations, in
1204 // case we see any later on.
1205 this->rel_tls_desc(layout
);
1206 this->irelative_rel_
= new Reloc_section(false);
1207 layout
->add_output_section_data(".rel.plt", elfcpp::SHT_REL
,
1208 elfcpp::SHF_ALLOC
, this->irelative_rel_
,
1209 ORDER_DYNAMIC_PLT_RELOCS
, false);
1210 gold_assert(this->irelative_rel_
->output_section()
1211 == this->rel_
->output_section());
1213 if (parameters
->doing_static_link())
1215 // A statically linked executable will only have a .rel.plt
1216 // section to hold R_386_IRELATIVE relocs for STT_GNU_IFUNC
1217 // symbols. The library will use these symbols to locate
1218 // the IRELATIVE relocs at program startup time.
1219 symtab
->define_in_output_data("__rel_iplt_start", NULL
,
1220 Symbol_table::PREDEFINED
,
1221 this->irelative_rel_
, 0, 0,
1222 elfcpp::STT_NOTYPE
, elfcpp::STB_GLOBAL
,
1223 elfcpp::STV_HIDDEN
, 0, false, true);
1224 symtab
->define_in_output_data("__rel_iplt_end", NULL
,
1225 Symbol_table::PREDEFINED
,
1226 this->irelative_rel_
, 0, 0,
1227 elfcpp::STT_NOTYPE
, elfcpp::STB_GLOBAL
,
1228 elfcpp::STV_HIDDEN
, 0, true, true);
1231 return this->irelative_rel_
;
1234 // Return the PLT address to use for a global symbol.
1237 Output_data_plt_i386::address_for_global(const Symbol
* gsym
)
1239 uint64_t offset
= 0;
1240 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
1241 && gsym
->can_use_relative_reloc(false))
1242 offset
= (this->count_
+ 1) * this->get_plt_entry_size();
1243 return this->address() + offset
+ gsym
->plt_offset();
1246 // Return the PLT address to use for a local symbol. These are always
1247 // IRELATIVE relocs.
1250 Output_data_plt_i386::address_for_local(const Relobj
* object
,
1253 return (this->address()
1254 + (this->count_
+ 1) * this->get_plt_entry_size()
1255 + object
->local_plt_offset(r_sym
));
1258 // The first entry in the PLT for an executable.
1260 const unsigned char Output_data_plt_i386_exec::first_plt_entry
[plt_entry_size
] =
1262 0xff, 0x35, // pushl contents of memory address
1263 0, 0, 0, 0, // replaced with address of .got + 4
1264 0xff, 0x25, // jmp indirect
1265 0, 0, 0, 0, // replaced with address of .got + 8
1266 0, 0, 0, 0 // unused
1270 Output_data_plt_i386_exec::do_fill_first_plt_entry(
1272 elfcpp::Elf_types
<32>::Elf_Addr got_address
)
1274 memcpy(pov
, first_plt_entry
, plt_entry_size
);
1275 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2, got_address
+ 4);
1276 elfcpp::Swap
<32, false>::writeval(pov
+ 8, got_address
+ 8);
1279 // The first entry in the PLT for a shared object.
1281 const unsigned char Output_data_plt_i386_dyn::first_plt_entry
[plt_entry_size
] =
1283 0xff, 0xb3, 4, 0, 0, 0, // pushl 4(%ebx)
1284 0xff, 0xa3, 8, 0, 0, 0, // jmp *8(%ebx)
1285 0, 0, 0, 0 // unused
1289 Output_data_plt_i386_dyn::do_fill_first_plt_entry(
1291 elfcpp::Elf_types
<32>::Elf_Addr
)
1293 memcpy(pov
, first_plt_entry
, plt_entry_size
);
1296 // Subsequent entries in the PLT for an executable.
1298 const unsigned char Output_data_plt_i386_exec::plt_entry
[plt_entry_size
] =
1300 0xff, 0x25, // jmp indirect
1301 0, 0, 0, 0, // replaced with address of symbol in .got
1302 0x68, // pushl immediate
1303 0, 0, 0, 0, // replaced with offset into relocation table
1304 0xe9, // jmp relative
1305 0, 0, 0, 0 // replaced with offset to start of .plt
1309 Output_data_plt_i386_exec::do_fill_plt_entry(
1311 elfcpp::Elf_types
<32>::Elf_Addr got_address
,
1312 unsigned int got_offset
,
1313 unsigned int plt_offset
,
1314 unsigned int plt_rel_offset
)
1316 memcpy(pov
, plt_entry
, plt_entry_size
);
1317 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
1318 got_address
+ 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 // Subsequent entries in the PLT for a shared object.
1326 const unsigned char Output_data_plt_i386_dyn::plt_entry
[plt_entry_size
] =
1328 0xff, 0xa3, // jmp *offset(%ebx)
1329 0, 0, 0, 0, // replaced with offset of symbol in .got
1330 0x68, // pushl immediate
1331 0, 0, 0, 0, // replaced with offset into relocation table
1332 0xe9, // jmp relative
1333 0, 0, 0, 0 // replaced with offset to start of .plt
1337 Output_data_plt_i386_dyn::do_fill_plt_entry(unsigned char* pov
,
1338 elfcpp::Elf_types
<32>::Elf_Addr
,
1339 unsigned int got_offset
,
1340 unsigned int plt_offset
,
1341 unsigned int plt_rel_offset
)
1343 memcpy(pov
, plt_entry
, plt_entry_size
);
1344 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2, got_offset
);
1345 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 7, plt_rel_offset
);
1346 elfcpp::Swap
<32, false>::writeval(pov
+ 12, - (plt_offset
+ 12 + 4));
1350 // The .eh_frame unwind information for the PLT.
1353 Output_data_plt_i386::plt_eh_frame_cie
[plt_eh_frame_cie_size
] =
1356 'z', // Augmentation: augmentation size included.
1357 'R', // Augmentation: FDE encoding included.
1358 '\0', // End of augmentation string.
1359 1, // Code alignment factor.
1360 0x7c, // Data alignment factor.
1361 8, // Return address column.
1362 1, // Augmentation size.
1363 (elfcpp::DW_EH_PE_pcrel
// FDE encoding.
1364 | elfcpp::DW_EH_PE_sdata4
),
1365 elfcpp::DW_CFA_def_cfa
, 4, 4, // DW_CFA_def_cfa: r4 (esp) ofs 4.
1366 elfcpp::DW_CFA_offset
+ 8, 1, // DW_CFA_offset: r8 (eip) at cfa-4.
1367 elfcpp::DW_CFA_nop
, // Align to 16 bytes.
1372 Output_data_plt_i386_standard::plt_eh_frame_fde
[plt_eh_frame_fde_size
] =
1374 0, 0, 0, 0, // Replaced with offset to .plt.
1375 0, 0, 0, 0, // Replaced with size of .plt.
1376 0, // Augmentation size.
1377 elfcpp::DW_CFA_def_cfa_offset
, 8, // DW_CFA_def_cfa_offset: 8.
1378 elfcpp::DW_CFA_advance_loc
+ 6, // Advance 6 to __PLT__ + 6.
1379 elfcpp::DW_CFA_def_cfa_offset
, 12, // DW_CFA_def_cfa_offset: 12.
1380 elfcpp::DW_CFA_advance_loc
+ 10, // Advance 10 to __PLT__ + 16.
1381 elfcpp::DW_CFA_def_cfa_expression
, // DW_CFA_def_cfa_expression.
1382 11, // Block length.
1383 elfcpp::DW_OP_breg4
, 4, // Push %esp + 4.
1384 elfcpp::DW_OP_breg8
, 0, // Push %eip.
1385 elfcpp::DW_OP_lit15
, // Push 0xf.
1386 elfcpp::DW_OP_and
, // & (%eip & 0xf).
1387 elfcpp::DW_OP_lit11
, // Push 0xb.
1388 elfcpp::DW_OP_ge
, // >= ((%eip & 0xf) >= 0xb)
1389 elfcpp::DW_OP_lit2
, // Push 2.
1390 elfcpp::DW_OP_shl
, // << (((%eip & 0xf) >= 0xb) << 2)
1391 elfcpp::DW_OP_plus
, // + ((((%eip&0xf)>=0xb)<<2)+%esp+4
1392 elfcpp::DW_CFA_nop
, // Align to 32 bytes.
1398 // Write out the PLT. This uses the hand-coded instructions above,
1399 // and adjusts them as needed. This is all specified by the i386 ELF
1400 // Processor Supplement.
1403 Output_data_plt_i386::do_write(Output_file
* of
)
1405 const off_t offset
= this->offset();
1406 const section_size_type oview_size
=
1407 convert_to_section_size_type(this->data_size());
1408 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
1410 const off_t got_file_offset
= this->got_plt_
->offset();
1411 gold_assert(parameters
->incremental_update()
1412 || (got_file_offset
+ this->got_plt_
->data_size()
1413 == this->got_irelative_
->offset()));
1414 const section_size_type got_size
=
1415 convert_to_section_size_type(this->got_plt_
->data_size()
1416 + this->got_irelative_
->data_size());
1418 unsigned char* const got_view
= of
->get_output_view(got_file_offset
,
1421 unsigned char* pov
= oview
;
1423 elfcpp::Elf_types
<32>::Elf_Addr plt_address
= this->address();
1424 elfcpp::Elf_types
<32>::Elf_Addr got_address
= this->got_plt_
->address();
1426 this->fill_first_plt_entry(pov
, got_address
);
1427 pov
+= this->get_plt_entry_size();
1429 // The first three entries in the GOT are reserved, and are written
1430 // by Output_data_got_plt_i386::do_write.
1431 unsigned char* got_pov
= got_view
+ 12;
1433 const int rel_size
= elfcpp::Elf_sizes
<32>::rel_size
;
1435 unsigned int plt_offset
= this->get_plt_entry_size();
1436 unsigned int plt_rel_offset
= 0;
1437 unsigned int got_offset
= 12;
1438 const unsigned int count
= this->count_
+ this->irelative_count_
;
1439 for (unsigned int i
= 0;
1442 pov
+= this->get_plt_entry_size(),
1444 plt_offset
+= this->get_plt_entry_size(),
1445 plt_rel_offset
+= rel_size
,
1448 // Set and adjust the PLT entry itself.
1449 unsigned int lazy_offset
= this->fill_plt_entry(pov
,
1455 // Set the entry in the GOT.
1456 elfcpp::Swap
<32, false>::writeval(got_pov
,
1457 plt_address
+ plt_offset
+ lazy_offset
);
1460 // If any STT_GNU_IFUNC symbols have PLT entries, we need to change
1461 // the GOT to point to the actual symbol value, rather than point to
1462 // the PLT entry. That will let the dynamic linker call the right
1463 // function when resolving IRELATIVE relocations.
1464 unsigned char* got_irelative_view
= got_view
+ this->got_plt_
->data_size();
1465 for (std::vector
<Global_ifunc
>::const_iterator p
=
1466 this->global_ifuncs_
.begin();
1467 p
!= this->global_ifuncs_
.end();
1470 const Sized_symbol
<32>* ssym
=
1471 static_cast<const Sized_symbol
<32>*>(p
->sym
);
1472 elfcpp::Swap
<32, false>::writeval(got_irelative_view
+ p
->got_offset
,
1476 for (std::vector
<Local_ifunc
>::const_iterator p
=
1477 this->local_ifuncs_
.begin();
1478 p
!= this->local_ifuncs_
.end();
1481 const Symbol_value
<32>* psymval
=
1482 p
->object
->local_symbol(p
->local_sym_index
);
1483 elfcpp::Swap
<32, false>::writeval(got_irelative_view
+ p
->got_offset
,
1484 psymval
->value(p
->object
, 0));
1487 gold_assert(static_cast<section_size_type
>(pov
- oview
) == oview_size
);
1488 gold_assert(static_cast<section_size_type
>(got_pov
- got_view
) == got_size
);
1490 of
->write_output_view(offset
, oview_size
, oview
);
1491 of
->write_output_view(got_file_offset
, got_size
, got_view
);
1494 // Create the PLT section.
1497 Target_i386::make_plt_section(Symbol_table
* symtab
, Layout
* layout
)
1499 if (this->plt_
== NULL
)
1501 // Create the GOT sections first.
1502 this->got_section(symtab
, layout
);
1504 const bool dyn
= parameters
->options().output_is_position_independent();
1505 this->plt_
= this->make_data_plt(layout
,
1507 this->got_irelative_
,
1510 // Add unwind information if requested.
1511 if (parameters
->options().ld_generated_unwind_info())
1512 this->plt_
->add_eh_frame(layout
);
1514 layout
->add_output_section_data(".plt", elfcpp::SHT_PROGBITS
,
1516 | elfcpp::SHF_EXECINSTR
),
1517 this->plt_
, ORDER_PLT
, false);
1519 // Make the sh_info field of .rel.plt point to .plt.
1520 Output_section
* rel_plt_os
= this->plt_
->rel_plt()->output_section();
1521 rel_plt_os
->set_info_section(this->plt_
->output_section());
1525 // Create a PLT entry for a global symbol.
1528 Target_i386::make_plt_entry(Symbol_table
* symtab
, Layout
* layout
, Symbol
* gsym
)
1530 if (gsym
->has_plt_offset())
1532 if (this->plt_
== NULL
)
1533 this->make_plt_section(symtab
, layout
);
1534 this->plt_
->add_entry(symtab
, layout
, gsym
);
1537 // Make a PLT entry for a local STT_GNU_IFUNC symbol.
1540 Target_i386::make_local_ifunc_plt_entry(Symbol_table
* symtab
, Layout
* layout
,
1541 Sized_relobj_file
<32, false>* relobj
,
1542 unsigned int local_sym_index
)
1544 if (relobj
->local_has_plt_offset(local_sym_index
))
1546 if (this->plt_
== NULL
)
1547 this->make_plt_section(symtab
, layout
);
1548 unsigned int plt_offset
= this->plt_
->add_local_ifunc_entry(symtab
, layout
,
1551 relobj
->set_local_plt_offset(local_sym_index
, plt_offset
);
1554 // Return the number of entries in the PLT.
1557 Target_i386::plt_entry_count() const
1559 if (this->plt_
== NULL
)
1561 return this->plt_
->entry_count();
1564 // Return the offset of the first non-reserved PLT entry.
1567 Target_i386::first_plt_entry_offset() const
1569 if (this->plt_
== NULL
)
1571 return this->plt_
->first_plt_entry_offset();
1574 // Return the size of each PLT entry.
1577 Target_i386::plt_entry_size() const
1579 if (this->plt_
== NULL
)
1581 return this->plt_
->get_plt_entry_size();
1584 // Get the section to use for TLS_DESC relocations.
1586 Target_i386::Reloc_section
*
1587 Target_i386::rel_tls_desc_section(Layout
* layout
) const
1589 return this->plt_section()->rel_tls_desc(layout
);
1592 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
1595 Target_i386::define_tls_base_symbol(Symbol_table
* symtab
, Layout
* layout
)
1597 if (this->tls_base_symbol_defined_
)
1600 Output_segment
* tls_segment
= layout
->tls_segment();
1601 if (tls_segment
!= NULL
)
1603 bool is_exec
= parameters
->options().output_is_executable();
1604 symtab
->define_in_output_segment("_TLS_MODULE_BASE_", NULL
,
1605 Symbol_table::PREDEFINED
,
1609 elfcpp::STV_HIDDEN
, 0,
1611 ? Symbol::SEGMENT_END
1612 : Symbol::SEGMENT_START
),
1615 this->tls_base_symbol_defined_
= true;
1618 // Create a GOT entry for the TLS module index.
1621 Target_i386::got_mod_index_entry(Symbol_table
* symtab
, Layout
* layout
,
1622 Sized_relobj_file
<32, false>* object
)
1624 if (this->got_mod_index_offset_
== -1U)
1626 gold_assert(symtab
!= NULL
&& layout
!= NULL
&& object
!= NULL
);
1627 Reloc_section
* rel_dyn
= this->rel_dyn_section(layout
);
1628 Output_data_got
<32, false>* got
= this->got_section(symtab
, layout
);
1629 unsigned int got_offset
= got
->add_constant(0);
1630 rel_dyn
->add_local(object
, 0, elfcpp::R_386_TLS_DTPMOD32
, got
,
1632 got
->add_constant(0);
1633 this->got_mod_index_offset_
= got_offset
;
1635 return this->got_mod_index_offset_
;
1638 // Optimize the TLS relocation type based on what we know about the
1639 // symbol. IS_FINAL is true if the final address of this symbol is
1640 // known at link time.
1642 tls::Tls_optimization
1643 Target_i386::optimize_tls_reloc(bool is_final
, int r_type
)
1645 // If we are generating a shared library, then we can't do anything
1647 if (parameters
->options().shared())
1648 return tls::TLSOPT_NONE
;
1652 case elfcpp::R_386_TLS_GD
:
1653 case elfcpp::R_386_TLS_GOTDESC
:
1654 case elfcpp::R_386_TLS_DESC_CALL
:
1655 // These are General-Dynamic which permits fully general TLS
1656 // access. Since we know that we are generating an executable,
1657 // we can convert this to Initial-Exec. If we also know that
1658 // this is a local symbol, we can further switch to Local-Exec.
1660 return tls::TLSOPT_TO_LE
;
1661 return tls::TLSOPT_TO_IE
;
1663 case elfcpp::R_386_TLS_LDM
:
1664 // This is Local-Dynamic, which refers to a local symbol in the
1665 // dynamic TLS block. Since we know that we generating an
1666 // executable, we can switch to Local-Exec.
1667 return tls::TLSOPT_TO_LE
;
1669 case elfcpp::R_386_TLS_LDO_32
:
1670 // Another type of Local-Dynamic relocation.
1671 return tls::TLSOPT_TO_LE
;
1673 case elfcpp::R_386_TLS_IE
:
1674 case elfcpp::R_386_TLS_GOTIE
:
1675 case elfcpp::R_386_TLS_IE_32
:
1676 // These are Initial-Exec relocs which get the thread offset
1677 // from the GOT. If we know that we are linking against the
1678 // local symbol, we can switch to Local-Exec, which links the
1679 // thread offset into the instruction.
1681 return tls::TLSOPT_TO_LE
;
1682 return tls::TLSOPT_NONE
;
1684 case elfcpp::R_386_TLS_LE
:
1685 case elfcpp::R_386_TLS_LE_32
:
1686 // When we already have Local-Exec, there is nothing further we
1688 return tls::TLSOPT_NONE
;
1695 // Get the Reference_flags for a particular relocation.
1698 Target_i386::Scan::get_reference_flags(unsigned int r_type
)
1702 case elfcpp::R_386_NONE
:
1703 case elfcpp::R_386_GNU_VTINHERIT
:
1704 case elfcpp::R_386_GNU_VTENTRY
:
1705 case elfcpp::R_386_GOTPC
:
1706 // No symbol reference.
1709 case elfcpp::R_386_32
:
1710 case elfcpp::R_386_16
:
1711 case elfcpp::R_386_8
:
1712 return Symbol::ABSOLUTE_REF
;
1714 case elfcpp::R_386_PC32
:
1715 case elfcpp::R_386_PC16
:
1716 case elfcpp::R_386_PC8
:
1717 case elfcpp::R_386_GOTOFF
:
1718 return Symbol::RELATIVE_REF
;
1720 case elfcpp::R_386_PLT32
:
1721 return Symbol::FUNCTION_CALL
| Symbol::RELATIVE_REF
;
1723 case elfcpp::R_386_GOT32
:
1724 case elfcpp::R_386_GOT32X
:
1726 return Symbol::ABSOLUTE_REF
;
1728 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1729 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
1730 case elfcpp::R_386_TLS_DESC_CALL
:
1731 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1732 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1733 case elfcpp::R_386_TLS_IE
: // Initial-exec
1734 case elfcpp::R_386_TLS_IE_32
:
1735 case elfcpp::R_386_TLS_GOTIE
:
1736 case elfcpp::R_386_TLS_LE
: // Local-exec
1737 case elfcpp::R_386_TLS_LE_32
:
1738 return Symbol::TLS_REF
;
1740 case elfcpp::R_386_COPY
:
1741 case elfcpp::R_386_GLOB_DAT
:
1742 case elfcpp::R_386_JUMP_SLOT
:
1743 case elfcpp::R_386_RELATIVE
:
1744 case elfcpp::R_386_IRELATIVE
:
1745 case elfcpp::R_386_TLS_TPOFF
:
1746 case elfcpp::R_386_TLS_DTPMOD32
:
1747 case elfcpp::R_386_TLS_DTPOFF32
:
1748 case elfcpp::R_386_TLS_TPOFF32
:
1749 case elfcpp::R_386_TLS_DESC
:
1750 case elfcpp::R_386_32PLT
:
1751 case elfcpp::R_386_TLS_GD_32
:
1752 case elfcpp::R_386_TLS_GD_PUSH
:
1753 case elfcpp::R_386_TLS_GD_CALL
:
1754 case elfcpp::R_386_TLS_GD_POP
:
1755 case elfcpp::R_386_TLS_LDM_32
:
1756 case elfcpp::R_386_TLS_LDM_PUSH
:
1757 case elfcpp::R_386_TLS_LDM_CALL
:
1758 case elfcpp::R_386_TLS_LDM_POP
:
1759 case elfcpp::R_386_USED_BY_INTEL_200
:
1761 // Not expected. We will give an error later.
1766 // Report an unsupported relocation against a local symbol.
1769 Target_i386::Scan::unsupported_reloc_local(Sized_relobj_file
<32, false>* object
,
1770 unsigned int r_type
)
1772 gold_error(_("%s: unsupported reloc %u against local symbol"),
1773 object
->name().c_str(), r_type
);
1776 // Return whether we need to make a PLT entry for a relocation of a
1777 // given type against a STT_GNU_IFUNC symbol.
1780 Target_i386::Scan::reloc_needs_plt_for_ifunc(
1781 Sized_relobj_file
<32, false>* object
,
1782 unsigned int r_type
)
1784 int flags
= Scan::get_reference_flags(r_type
);
1785 if (flags
& Symbol::TLS_REF
)
1786 gold_error(_("%s: unsupported TLS reloc %u for IFUNC symbol"),
1787 object
->name().c_str(), r_type
);
1791 // Scan a relocation for a local symbol.
1794 Target_i386::Scan::local(Symbol_table
* symtab
,
1796 Target_i386
* target
,
1797 Sized_relobj_file
<32, false>* object
,
1798 unsigned int data_shndx
,
1799 Output_section
* output_section
,
1800 const elfcpp::Rel
<32, false>& reloc
,
1801 unsigned int r_type
,
1802 const elfcpp::Sym
<32, false>& lsym
,
1808 // A local STT_GNU_IFUNC symbol may require a PLT entry.
1809 if (lsym
.get_st_type() == elfcpp::STT_GNU_IFUNC
1810 && this->reloc_needs_plt_for_ifunc(object
, r_type
))
1812 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1813 target
->make_local_ifunc_plt_entry(symtab
, layout
, object
, r_sym
);
1818 case elfcpp::R_386_NONE
:
1819 case elfcpp::R_386_GNU_VTINHERIT
:
1820 case elfcpp::R_386_GNU_VTENTRY
:
1823 case elfcpp::R_386_32
:
1824 // If building a shared library (or a position-independent
1825 // executable), we need to create a dynamic relocation for
1826 // this location. The relocation applied at link time will
1827 // apply the link-time value, so we flag the location with
1828 // an R_386_RELATIVE relocation so the dynamic loader can
1829 // relocate it easily.
1830 if (parameters
->options().output_is_position_independent())
1832 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1833 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1834 rel_dyn
->add_local_relative(object
, r_sym
, elfcpp::R_386_RELATIVE
,
1835 output_section
, data_shndx
,
1836 reloc
.get_r_offset());
1840 case elfcpp::R_386_16
:
1841 case elfcpp::R_386_8
:
1842 // If building a shared library (or a position-independent
1843 // executable), we need to create a dynamic relocation for
1844 // this location. Because the addend needs to remain in the
1845 // data section, we need to be careful not to apply this
1846 // relocation statically.
1847 if (parameters
->options().output_is_position_independent())
1849 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1850 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1851 if (lsym
.get_st_type() != elfcpp::STT_SECTION
)
1852 rel_dyn
->add_local(object
, r_sym
, r_type
, output_section
,
1853 data_shndx
, reloc
.get_r_offset());
1856 gold_assert(lsym
.get_st_value() == 0);
1857 unsigned int shndx
= lsym
.get_st_shndx();
1859 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
,
1862 object
->error(_("section symbol %u has bad shndx %u"),
1865 rel_dyn
->add_local_section(object
, shndx
,
1866 r_type
, output_section
,
1867 data_shndx
, reloc
.get_r_offset());
1872 case elfcpp::R_386_PC32
:
1873 case elfcpp::R_386_PC16
:
1874 case elfcpp::R_386_PC8
:
1877 case elfcpp::R_386_PLT32
:
1878 // Since we know this is a local symbol, we can handle this as a
1882 case elfcpp::R_386_GOTOFF
:
1883 case elfcpp::R_386_GOTPC
:
1884 // We need a GOT section.
1885 target
->got_section(symtab
, layout
);
1888 case elfcpp::R_386_GOT32
:
1889 case elfcpp::R_386_GOT32X
:
1891 // We need GOT section.
1892 Output_data_got
<32, false>* got
= target
->got_section(symtab
, layout
);
1894 // If the relocation symbol isn't IFUNC,
1895 // and is local, then we will convert
1896 // mov foo@GOT(%reg), %reg
1898 // lea foo@GOTOFF(%reg), %reg
1899 // in Relocate::relocate.
1900 if (reloc
.get_r_offset() >= 2
1901 && lsym
.get_st_type() != elfcpp::STT_GNU_IFUNC
)
1903 section_size_type stype
;
1904 const unsigned char* view
= object
->section_contents(data_shndx
,
1906 if (view
[reloc
.get_r_offset() - 2] == 0x8b)
1910 // Otherwise, the symbol requires a GOT entry.
1911 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1913 // For a STT_GNU_IFUNC symbol we want the PLT offset. That
1914 // lets function pointers compare correctly with shared
1915 // libraries. Otherwise we would need an IRELATIVE reloc.
1917 if (lsym
.get_st_type() == elfcpp::STT_GNU_IFUNC
)
1918 is_new
= got
->add_local_plt(object
, r_sym
, GOT_TYPE_STANDARD
);
1920 is_new
= got
->add_local(object
, r_sym
, GOT_TYPE_STANDARD
);
1923 // If we are generating a shared object, we need to add a
1924 // dynamic RELATIVE relocation for this symbol's GOT entry.
1925 if (parameters
->options().output_is_position_independent())
1927 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1928 unsigned int got_offset
=
1929 object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
);
1930 rel_dyn
->add_local_relative(object
, r_sym
,
1931 elfcpp::R_386_RELATIVE
,
1938 // These are relocations which should only be seen by the
1939 // dynamic linker, and should never be seen here.
1940 case elfcpp::R_386_COPY
:
1941 case elfcpp::R_386_GLOB_DAT
:
1942 case elfcpp::R_386_JUMP_SLOT
:
1943 case elfcpp::R_386_RELATIVE
:
1944 case elfcpp::R_386_IRELATIVE
:
1945 case elfcpp::R_386_TLS_TPOFF
:
1946 case elfcpp::R_386_TLS_DTPMOD32
:
1947 case elfcpp::R_386_TLS_DTPOFF32
:
1948 case elfcpp::R_386_TLS_TPOFF32
:
1949 case elfcpp::R_386_TLS_DESC
:
1950 gold_error(_("%s: unexpected reloc %u in object file"),
1951 object
->name().c_str(), r_type
);
1954 // These are initial TLS relocs, which are expected when
1956 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1957 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
1958 case elfcpp::R_386_TLS_DESC_CALL
:
1959 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1960 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1961 case elfcpp::R_386_TLS_IE
: // Initial-exec
1962 case elfcpp::R_386_TLS_IE_32
:
1963 case elfcpp::R_386_TLS_GOTIE
:
1964 case elfcpp::R_386_TLS_LE
: // Local-exec
1965 case elfcpp::R_386_TLS_LE_32
:
1967 bool output_is_shared
= parameters
->options().shared();
1968 const tls::Tls_optimization optimized_type
1969 = Target_i386::optimize_tls_reloc(!output_is_shared
, r_type
);
1972 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1973 if (optimized_type
== tls::TLSOPT_NONE
)
1975 // Create a pair of GOT entries for the module index and
1976 // dtv-relative offset.
1977 Output_data_got
<32, false>* got
1978 = target
->got_section(symtab
, layout
);
1979 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1980 unsigned int shndx
= lsym
.get_st_shndx();
1982 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
, &is_ordinary
);
1984 object
->error(_("local symbol %u has bad shndx %u"),
1987 got
->add_local_pair_with_rel(object
, r_sym
, shndx
,
1989 target
->rel_dyn_section(layout
),
1990 elfcpp::R_386_TLS_DTPMOD32
);
1992 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1993 unsupported_reloc_local(object
, r_type
);
1996 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva)
1997 target
->define_tls_base_symbol(symtab
, layout
);
1998 if (optimized_type
== tls::TLSOPT_NONE
)
2000 // Create a double GOT entry with an R_386_TLS_DESC
2001 // reloc. The R_386_TLS_DESC reloc is resolved
2002 // lazily, so the GOT entry needs to be in an area in
2003 // .got.plt, not .got. Call got_section to make sure
2004 // the section has been created.
2005 target
->got_section(symtab
, layout
);
2006 Output_data_got
<32, false>* got
= target
->got_tlsdesc_section();
2007 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
2008 if (!object
->local_has_got_offset(r_sym
, GOT_TYPE_TLS_DESC
))
2010 unsigned int got_offset
= got
->add_constant(0);
2011 // The local symbol value is stored in the second
2013 got
->add_local(object
, r_sym
, GOT_TYPE_TLS_DESC
);
2014 // That set the GOT offset of the local symbol to
2015 // point to the second entry, but we want it to
2016 // point to the first.
2017 object
->set_local_got_offset(r_sym
, GOT_TYPE_TLS_DESC
,
2019 Reloc_section
* rt
= target
->rel_tls_desc_section(layout
);
2020 rt
->add_absolute(elfcpp::R_386_TLS_DESC
, got
, got_offset
);
2023 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2024 unsupported_reloc_local(object
, r_type
);
2027 case elfcpp::R_386_TLS_DESC_CALL
:
2030 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
2031 if (optimized_type
== tls::TLSOPT_NONE
)
2033 // Create a GOT entry for the module index.
2034 target
->got_mod_index_entry(symtab
, layout
, object
);
2036 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2037 unsupported_reloc_local(object
, r_type
);
2040 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
2043 case elfcpp::R_386_TLS_IE
: // Initial-exec
2044 case elfcpp::R_386_TLS_IE_32
:
2045 case elfcpp::R_386_TLS_GOTIE
:
2046 layout
->set_has_static_tls();
2047 if (optimized_type
== tls::TLSOPT_NONE
)
2049 // For the R_386_TLS_IE relocation, we need to create a
2050 // dynamic relocation when building a shared library.
2051 if (r_type
== elfcpp::R_386_TLS_IE
2052 && parameters
->options().shared())
2054 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
2056 = elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
2057 rel_dyn
->add_local_relative(object
, r_sym
,
2058 elfcpp::R_386_RELATIVE
,
2059 output_section
, data_shndx
,
2060 reloc
.get_r_offset());
2062 // Create a GOT entry for the tp-relative offset.
2063 Output_data_got
<32, false>* got
2064 = target
->got_section(symtab
, layout
);
2065 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
2066 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_IE_32
2067 ? elfcpp::R_386_TLS_TPOFF32
2068 : elfcpp::R_386_TLS_TPOFF
);
2069 unsigned int got_type
= (r_type
== elfcpp::R_386_TLS_IE_32
2070 ? GOT_TYPE_TLS_OFFSET
2071 : GOT_TYPE_TLS_NOFFSET
);
2072 got
->add_local_with_rel(object
, r_sym
, got_type
,
2073 target
->rel_dyn_section(layout
),
2076 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2077 unsupported_reloc_local(object
, r_type
);
2080 case elfcpp::R_386_TLS_LE
: // Local-exec
2081 case elfcpp::R_386_TLS_LE_32
:
2082 layout
->set_has_static_tls();
2083 if (output_is_shared
)
2085 // We need to create a dynamic relocation.
2086 gold_assert(lsym
.get_st_type() != elfcpp::STT_SECTION
);
2087 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
2088 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_LE_32
2089 ? elfcpp::R_386_TLS_TPOFF32
2090 : elfcpp::R_386_TLS_TPOFF
);
2091 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
2092 rel_dyn
->add_local(object
, r_sym
, dyn_r_type
, output_section
,
2093 data_shndx
, reloc
.get_r_offset());
2103 case elfcpp::R_386_32PLT
:
2104 case elfcpp::R_386_TLS_GD_32
:
2105 case elfcpp::R_386_TLS_GD_PUSH
:
2106 case elfcpp::R_386_TLS_GD_CALL
:
2107 case elfcpp::R_386_TLS_GD_POP
:
2108 case elfcpp::R_386_TLS_LDM_32
:
2109 case elfcpp::R_386_TLS_LDM_PUSH
:
2110 case elfcpp::R_386_TLS_LDM_CALL
:
2111 case elfcpp::R_386_TLS_LDM_POP
:
2112 case elfcpp::R_386_USED_BY_INTEL_200
:
2114 unsupported_reloc_local(object
, r_type
);
2119 // Report an unsupported relocation against a global symbol.
2122 Target_i386::Scan::unsupported_reloc_global(
2123 Sized_relobj_file
<32, false>* object
,
2124 unsigned int r_type
,
2127 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
2128 object
->name().c_str(), r_type
, gsym
->demangled_name().c_str());
2132 Target_i386::Scan::possible_function_pointer_reloc(unsigned int r_type
)
2136 case elfcpp::R_386_32
:
2137 case elfcpp::R_386_16
:
2138 case elfcpp::R_386_8
:
2139 case elfcpp::R_386_GOTOFF
:
2140 case elfcpp::R_386_GOT32
:
2141 case elfcpp::R_386_GOT32X
:
2152 Target_i386::Scan::local_reloc_may_be_function_pointer(
2156 Sized_relobj_file
<32, false>* ,
2159 const elfcpp::Rel
<32, false>& ,
2160 unsigned int r_type
,
2161 const elfcpp::Sym
<32, false>&)
2163 return possible_function_pointer_reloc(r_type
);
2167 Target_i386::Scan::global_reloc_may_be_function_pointer(
2171 Sized_relobj_file
<32, false>* ,
2174 const elfcpp::Rel
<32, false>& ,
2175 unsigned int r_type
,
2178 return possible_function_pointer_reloc(r_type
);
2181 // Scan a relocation for a global symbol.
2184 Target_i386::Scan::global(Symbol_table
* symtab
,
2186 Target_i386
* target
,
2187 Sized_relobj_file
<32, false>* object
,
2188 unsigned int data_shndx
,
2189 Output_section
* output_section
,
2190 const elfcpp::Rel
<32, false>& reloc
,
2191 unsigned int r_type
,
2194 // A STT_GNU_IFUNC symbol may require a PLT entry.
2195 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
2196 && this->reloc_needs_plt_for_ifunc(object
, r_type
))
2197 target
->make_plt_entry(symtab
, layout
, gsym
);
2201 case elfcpp::R_386_NONE
:
2202 case elfcpp::R_386_GNU_VTINHERIT
:
2203 case elfcpp::R_386_GNU_VTENTRY
:
2206 case elfcpp::R_386_32
:
2207 case elfcpp::R_386_16
:
2208 case elfcpp::R_386_8
:
2210 // Make a PLT entry if necessary.
2211 if (gsym
->needs_plt_entry())
2213 target
->make_plt_entry(symtab
, layout
, gsym
);
2214 // Since this is not a PC-relative relocation, we may be
2215 // taking the address of a function. In that case we need to
2216 // set the entry in the dynamic symbol table to the address of
2218 if (gsym
->is_from_dynobj() && !parameters
->options().shared())
2219 gsym
->set_needs_dynsym_value();
2221 // Make a dynamic relocation if necessary.
2222 if (gsym
->needs_dynamic_reloc(Scan::get_reference_flags(r_type
)))
2224 if (!parameters
->options().output_is_position_independent()
2225 && gsym
->may_need_copy_reloc())
2227 target
->copy_reloc(symtab
, layout
, object
,
2228 data_shndx
, output_section
, gsym
, reloc
);
2230 else if (r_type
== elfcpp::R_386_32
2231 && gsym
->type() == elfcpp::STT_GNU_IFUNC
2232 && gsym
->can_use_relative_reloc(false)
2233 && !gsym
->is_from_dynobj()
2234 && !gsym
->is_undefined()
2235 && !gsym
->is_preemptible())
2237 // Use an IRELATIVE reloc for a locally defined
2238 // STT_GNU_IFUNC symbol. This makes a function
2239 // address in a PIE executable match the address in a
2240 // shared library that it links against.
2241 Reloc_section
* rel_dyn
= target
->rel_irelative_section(layout
);
2242 rel_dyn
->add_symbolless_global_addend(gsym
,
2243 elfcpp::R_386_IRELATIVE
,
2246 reloc
.get_r_offset());
2248 else if (r_type
== elfcpp::R_386_32
2249 && gsym
->can_use_relative_reloc(false))
2251 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
2252 rel_dyn
->add_global_relative(gsym
, elfcpp::R_386_RELATIVE
,
2253 output_section
, object
,
2254 data_shndx
, reloc
.get_r_offset());
2258 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
2259 rel_dyn
->add_global(gsym
, r_type
, output_section
, object
,
2260 data_shndx
, reloc
.get_r_offset());
2266 case elfcpp::R_386_PC32
:
2267 case elfcpp::R_386_PC16
:
2268 case elfcpp::R_386_PC8
:
2270 // Make a PLT entry if necessary.
2271 if (gsym
->needs_plt_entry())
2273 // These relocations are used for function calls only in
2274 // non-PIC code. For a 32-bit relocation in a shared library,
2275 // we'll need a text relocation anyway, so we can skip the
2276 // PLT entry and let the dynamic linker bind the call directly
2277 // to the target. For smaller relocations, we should use a
2278 // PLT entry to ensure that the call can reach.
2279 if (!parameters
->options().shared()
2280 || r_type
!= elfcpp::R_386_PC32
)
2281 target
->make_plt_entry(symtab
, layout
, gsym
);
2283 // Make a dynamic relocation if necessary.
2284 if (gsym
->needs_dynamic_reloc(Scan::get_reference_flags(r_type
)))
2286 if (parameters
->options().output_is_executable()
2287 && gsym
->may_need_copy_reloc())
2289 target
->copy_reloc(symtab
, layout
, object
,
2290 data_shndx
, output_section
, gsym
, reloc
);
2294 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
2295 rel_dyn
->add_global(gsym
, r_type
, output_section
, object
,
2296 data_shndx
, reloc
.get_r_offset());
2302 case elfcpp::R_386_GOT32
:
2303 case elfcpp::R_386_GOT32X
:
2305 // The symbol requires a GOT section.
2306 Output_data_got
<32, false>* got
= target
->got_section(symtab
, layout
);
2308 // If we convert this from
2309 // mov foo@GOT(%reg), %reg
2311 // lea foo@GOTOFF(%reg), %reg
2312 // in Relocate::relocate, then there is nothing to do here.
2313 if (reloc
.get_r_offset() >= 2
2314 && Target_i386::can_convert_mov_to_lea(gsym
))
2316 section_size_type stype
;
2317 const unsigned char* view
= object
->section_contents(data_shndx
,
2319 if (view
[reloc
.get_r_offset() - 2] == 0x8b)
2323 if (gsym
->final_value_is_known())
2325 // For a STT_GNU_IFUNC symbol we want the PLT address.
2326 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
)
2327 got
->add_global_plt(gsym
, GOT_TYPE_STANDARD
);
2329 got
->add_global(gsym
, GOT_TYPE_STANDARD
);
2333 // If this symbol is not fully resolved, we need to add a
2334 // GOT entry with a dynamic relocation.
2335 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
2337 // Use a GLOB_DAT rather than a RELATIVE reloc if:
2339 // 1) The symbol may be defined in some other module.
2341 // 2) We are building a shared library and this is a
2342 // protected symbol; using GLOB_DAT means that the dynamic
2343 // linker can use the address of the PLT in the main
2344 // executable when appropriate so that function address
2345 // comparisons work.
2347 // 3) This is a STT_GNU_IFUNC symbol in position dependent
2348 // code, again so that function address comparisons work.
2349 if (gsym
->is_from_dynobj()
2350 || gsym
->is_undefined()
2351 || gsym
->is_preemptible()
2352 || (gsym
->visibility() == elfcpp::STV_PROTECTED
2353 && parameters
->options().shared())
2354 || (gsym
->type() == elfcpp::STT_GNU_IFUNC
2355 && parameters
->options().output_is_position_independent()))
2356 got
->add_global_with_rel(gsym
, GOT_TYPE_STANDARD
,
2357 rel_dyn
, elfcpp::R_386_GLOB_DAT
);
2360 // For a STT_GNU_IFUNC symbol we want to write the PLT
2361 // offset into the GOT, so that function pointer
2362 // comparisons work correctly.
2364 if (gsym
->type() != elfcpp::STT_GNU_IFUNC
)
2365 is_new
= got
->add_global(gsym
, GOT_TYPE_STANDARD
);
2368 is_new
= got
->add_global_plt(gsym
, GOT_TYPE_STANDARD
);
2369 // Tell the dynamic linker to use the PLT address
2370 // when resolving relocations.
2371 if (gsym
->is_from_dynobj()
2372 && !parameters
->options().shared())
2373 gsym
->set_needs_dynsym_value();
2377 unsigned int got_off
= gsym
->got_offset(GOT_TYPE_STANDARD
);
2378 rel_dyn
->add_global_relative(gsym
, elfcpp::R_386_RELATIVE
,
2386 case elfcpp::R_386_PLT32
:
2387 // If the symbol is fully resolved, this is just a PC32 reloc.
2388 // Otherwise we need a PLT entry.
2389 if (gsym
->final_value_is_known())
2391 // If building a shared library, we can also skip the PLT entry
2392 // if the symbol is defined in the output file and is protected
2394 if (gsym
->is_defined()
2395 && !gsym
->is_from_dynobj()
2396 && !gsym
->is_preemptible())
2398 target
->make_plt_entry(symtab
, layout
, gsym
);
2401 case elfcpp::R_386_GOTOFF
:
2402 // A GOT-relative reference must resolve locally.
2403 if (!gsym
->is_defined())
2404 gold_error(_("%s: relocation R_386_GOTOFF against undefined symbol %s"
2405 " cannot be used when making a shared object"),
2406 object
->name().c_str(), gsym
->name());
2407 else if (gsym
->is_from_dynobj())
2408 gold_error(_("%s: relocation R_386_GOTOFF against external symbol %s"
2409 " cannot be used when making a shared object"),
2410 object
->name().c_str(), gsym
->name());
2411 else if (gsym
->is_preemptible())
2412 gold_error(_("%s: relocation R_386_GOTOFF against preemptible symbol %s"
2413 " cannot be used when making a shared object"),
2414 object
->name().c_str(), gsym
->name());
2415 // We need a GOT section.
2416 target
->got_section(symtab
, layout
);
2419 case elfcpp::R_386_GOTPC
:
2420 // We need a GOT section.
2421 target
->got_section(symtab
, layout
);
2424 // These are relocations which should only be seen by the
2425 // dynamic linker, and should never be seen here.
2426 case elfcpp::R_386_COPY
:
2427 case elfcpp::R_386_GLOB_DAT
:
2428 case elfcpp::R_386_JUMP_SLOT
:
2429 case elfcpp::R_386_RELATIVE
:
2430 case elfcpp::R_386_IRELATIVE
:
2431 case elfcpp::R_386_TLS_TPOFF
:
2432 case elfcpp::R_386_TLS_DTPMOD32
:
2433 case elfcpp::R_386_TLS_DTPOFF32
:
2434 case elfcpp::R_386_TLS_TPOFF32
:
2435 case elfcpp::R_386_TLS_DESC
:
2436 gold_error(_("%s: unexpected reloc %u in object file"),
2437 object
->name().c_str(), r_type
);
2440 // These are initial tls relocs, which are expected when
2442 case elfcpp::R_386_TLS_GD
: // Global-dynamic
2443 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
2444 case elfcpp::R_386_TLS_DESC_CALL
:
2445 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
2446 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
2447 case elfcpp::R_386_TLS_IE
: // Initial-exec
2448 case elfcpp::R_386_TLS_IE_32
:
2449 case elfcpp::R_386_TLS_GOTIE
:
2450 case elfcpp::R_386_TLS_LE
: // Local-exec
2451 case elfcpp::R_386_TLS_LE_32
:
2453 const bool is_final
= gsym
->final_value_is_known();
2454 const tls::Tls_optimization optimized_type
2455 = Target_i386::optimize_tls_reloc(is_final
, r_type
);
2458 case elfcpp::R_386_TLS_GD
: // Global-dynamic
2459 if (optimized_type
== tls::TLSOPT_NONE
)
2461 // Create a pair of GOT entries for the module index and
2462 // dtv-relative offset.
2463 Output_data_got
<32, false>* got
2464 = target
->got_section(symtab
, layout
);
2465 got
->add_global_pair_with_rel(gsym
, GOT_TYPE_TLS_PAIR
,
2466 target
->rel_dyn_section(layout
),
2467 elfcpp::R_386_TLS_DTPMOD32
,
2468 elfcpp::R_386_TLS_DTPOFF32
);
2470 else if (optimized_type
== tls::TLSOPT_TO_IE
)
2472 // Create a GOT entry for the tp-relative offset.
2473 Output_data_got
<32, false>* got
2474 = target
->got_section(symtab
, layout
);
2475 got
->add_global_with_rel(gsym
, GOT_TYPE_TLS_NOFFSET
,
2476 target
->rel_dyn_section(layout
),
2477 elfcpp::R_386_TLS_TPOFF
);
2479 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2480 unsupported_reloc_global(object
, r_type
, gsym
);
2483 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (~oliva url)
2484 target
->define_tls_base_symbol(symtab
, layout
);
2485 if (optimized_type
== tls::TLSOPT_NONE
)
2487 // Create a double GOT entry with an R_386_TLS_DESC
2488 // reloc. The R_386_TLS_DESC reloc is resolved
2489 // lazily, so the GOT entry needs to be in an area in
2490 // .got.plt, not .got. Call got_section to make sure
2491 // the section has been created.
2492 target
->got_section(symtab
, layout
);
2493 Output_data_got
<32, false>* got
= target
->got_tlsdesc_section();
2494 Reloc_section
* rt
= target
->rel_tls_desc_section(layout
);
2495 got
->add_global_pair_with_rel(gsym
, GOT_TYPE_TLS_DESC
, rt
,
2496 elfcpp::R_386_TLS_DESC
, 0);
2498 else if (optimized_type
== tls::TLSOPT_TO_IE
)
2500 // Create a GOT entry for the tp-relative offset.
2501 Output_data_got
<32, false>* got
2502 = target
->got_section(symtab
, layout
);
2503 got
->add_global_with_rel(gsym
, GOT_TYPE_TLS_NOFFSET
,
2504 target
->rel_dyn_section(layout
),
2505 elfcpp::R_386_TLS_TPOFF
);
2507 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2508 unsupported_reloc_global(object
, r_type
, gsym
);
2511 case elfcpp::R_386_TLS_DESC_CALL
:
2514 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
2515 if (optimized_type
== tls::TLSOPT_NONE
)
2517 // Create a GOT entry for the module index.
2518 target
->got_mod_index_entry(symtab
, layout
, object
);
2520 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2521 unsupported_reloc_global(object
, r_type
, gsym
);
2524 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
2527 case elfcpp::R_386_TLS_IE
: // Initial-exec
2528 case elfcpp::R_386_TLS_IE_32
:
2529 case elfcpp::R_386_TLS_GOTIE
:
2530 layout
->set_has_static_tls();
2531 if (optimized_type
== tls::TLSOPT_NONE
)
2533 // For the R_386_TLS_IE relocation, we need to create a
2534 // dynamic relocation when building a shared library.
2535 if (r_type
== elfcpp::R_386_TLS_IE
2536 && parameters
->options().shared())
2538 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
2539 rel_dyn
->add_global_relative(gsym
, elfcpp::R_386_RELATIVE
,
2540 output_section
, object
,
2542 reloc
.get_r_offset());
2544 // Create a GOT entry for the tp-relative offset.
2545 Output_data_got
<32, false>* got
2546 = target
->got_section(symtab
, layout
);
2547 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_IE_32
2548 ? elfcpp::R_386_TLS_TPOFF32
2549 : elfcpp::R_386_TLS_TPOFF
);
2550 unsigned int got_type
= (r_type
== elfcpp::R_386_TLS_IE_32
2551 ? GOT_TYPE_TLS_OFFSET
2552 : GOT_TYPE_TLS_NOFFSET
);
2553 got
->add_global_with_rel(gsym
, got_type
,
2554 target
->rel_dyn_section(layout
),
2557 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2558 unsupported_reloc_global(object
, r_type
, gsym
);
2561 case elfcpp::R_386_TLS_LE
: // Local-exec
2562 case elfcpp::R_386_TLS_LE_32
:
2563 layout
->set_has_static_tls();
2564 if (parameters
->options().shared())
2566 // We need to create a dynamic relocation.
2567 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_LE_32
2568 ? elfcpp::R_386_TLS_TPOFF32
2569 : elfcpp::R_386_TLS_TPOFF
);
2570 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
2571 rel_dyn
->add_global(gsym
, dyn_r_type
, output_section
, object
,
2572 data_shndx
, reloc
.get_r_offset());
2582 case elfcpp::R_386_32PLT
:
2583 case elfcpp::R_386_TLS_GD_32
:
2584 case elfcpp::R_386_TLS_GD_PUSH
:
2585 case elfcpp::R_386_TLS_GD_CALL
:
2586 case elfcpp::R_386_TLS_GD_POP
:
2587 case elfcpp::R_386_TLS_LDM_32
:
2588 case elfcpp::R_386_TLS_LDM_PUSH
:
2589 case elfcpp::R_386_TLS_LDM_CALL
:
2590 case elfcpp::R_386_TLS_LDM_POP
:
2591 case elfcpp::R_386_USED_BY_INTEL_200
:
2593 unsupported_reloc_global(object
, r_type
, gsym
);
2598 // Process relocations for gc.
2601 Target_i386::gc_process_relocs(Symbol_table
* symtab
,
2603 Sized_relobj_file
<32, false>* object
,
2604 unsigned int data_shndx
,
2606 const unsigned char* prelocs
,
2608 Output_section
* output_section
,
2609 bool needs_special_offset_handling
,
2610 size_t local_symbol_count
,
2611 const unsigned char* plocal_symbols
)
2613 gold::gc_process_relocs
<32, false, Target_i386
, Scan
, Classify_reloc
>(
2622 needs_special_offset_handling
,
2627 // Scan relocations for a section.
2630 Target_i386::scan_relocs(Symbol_table
* symtab
,
2632 Sized_relobj_file
<32, false>* object
,
2633 unsigned int data_shndx
,
2634 unsigned int sh_type
,
2635 const unsigned char* prelocs
,
2637 Output_section
* output_section
,
2638 bool needs_special_offset_handling
,
2639 size_t local_symbol_count
,
2640 const unsigned char* plocal_symbols
)
2642 if (sh_type
== elfcpp::SHT_RELA
)
2644 gold_error(_("%s: unsupported RELA reloc section"),
2645 object
->name().c_str());
2649 gold::scan_relocs
<32, false, Target_i386
, Scan
, Classify_reloc
>(
2658 needs_special_offset_handling
,
2663 // Finalize the sections.
2666 Target_i386::do_finalize_sections(
2668 const Input_objects
*,
2669 Symbol_table
* symtab
)
2671 const Reloc_section
* rel_plt
= (this->plt_
== NULL
2673 : this->plt_
->rel_plt());
2674 layout
->add_target_dynamic_tags(true, this->got_plt_
, rel_plt
,
2675 this->rel_dyn_
, true, false);
2677 // Emit any relocs we saved in an attempt to avoid generating COPY
2679 if (this->copy_relocs_
.any_saved_relocs())
2680 this->copy_relocs_
.emit(this->rel_dyn_section(layout
));
2682 // Set the size of the _GLOBAL_OFFSET_TABLE_ symbol to the size of
2683 // the .got.plt section.
2684 Symbol
* sym
= this->global_offset_table_
;
2687 uint32_t data_size
= this->got_plt_
->current_data_size();
2688 symtab
->get_sized_symbol
<32>(sym
)->set_symsize(data_size
);
2691 if (parameters
->doing_static_link()
2692 && (this->plt_
== NULL
|| !this->plt_
->has_irelative_section()))
2694 // If linking statically, make sure that the __rel_iplt symbols
2695 // were defined if necessary, even if we didn't create a PLT.
2696 static const Define_symbol_in_segment syms
[] =
2699 "__rel_iplt_start", // name
2700 elfcpp::PT_LOAD
, // segment_type
2701 elfcpp::PF_W
, // segment_flags_set
2702 elfcpp::PF(0), // segment_flags_clear
2705 elfcpp::STT_NOTYPE
, // type
2706 elfcpp::STB_GLOBAL
, // binding
2707 elfcpp::STV_HIDDEN
, // visibility
2709 Symbol::SEGMENT_START
, // offset_from_base
2713 "__rel_iplt_end", // name
2714 elfcpp::PT_LOAD
, // segment_type
2715 elfcpp::PF_W
, // segment_flags_set
2716 elfcpp::PF(0), // segment_flags_clear
2719 elfcpp::STT_NOTYPE
, // type
2720 elfcpp::STB_GLOBAL
, // binding
2721 elfcpp::STV_HIDDEN
, // visibility
2723 Symbol::SEGMENT_START
, // offset_from_base
2728 symtab
->define_symbols(layout
, 2, syms
,
2729 layout
->script_options()->saw_sections_clause());
2733 // Return whether a direct absolute static relocation needs to be applied.
2734 // In cases where Scan::local() or Scan::global() has created
2735 // a dynamic relocation other than R_386_RELATIVE, the addend
2736 // of the relocation is carried in the data, and we must not
2737 // apply the static relocation.
2740 Target_i386::Relocate::should_apply_static_reloc(const Sized_symbol
<32>* gsym
,
2741 unsigned int r_type
,
2743 Output_section
* output_section
)
2745 // If the output section is not allocated, then we didn't call
2746 // scan_relocs, we didn't create a dynamic reloc, and we must apply
2748 if ((output_section
->flags() & elfcpp::SHF_ALLOC
) == 0)
2751 int ref_flags
= Scan::get_reference_flags(r_type
);
2753 // For local symbols, we will have created a non-RELATIVE dynamic
2754 // relocation only if (a) the output is position independent,
2755 // (b) the relocation is absolute (not pc- or segment-relative), and
2756 // (c) the relocation is not 32 bits wide.
2758 return !(parameters
->options().output_is_position_independent()
2759 && (ref_flags
& Symbol::ABSOLUTE_REF
)
2762 // For global symbols, we use the same helper routines used in the
2763 // scan pass. If we did not create a dynamic relocation, or if we
2764 // created a RELATIVE dynamic relocation, we should apply the static
2766 bool has_dyn
= gsym
->needs_dynamic_reloc(ref_flags
);
2767 bool is_rel
= (ref_flags
& Symbol::ABSOLUTE_REF
)
2768 && gsym
->can_use_relative_reloc(ref_flags
2769 & Symbol::FUNCTION_CALL
);
2770 return !has_dyn
|| is_rel
;
2773 // Perform a relocation.
2776 Target_i386::Relocate::relocate(const Relocate_info
<32, false>* relinfo
,
2778 Target_i386
* target
,
2779 Output_section
* output_section
,
2781 const unsigned char* preloc
,
2782 const Sized_symbol
<32>* gsym
,
2783 const Symbol_value
<32>* psymval
,
2784 unsigned char* view
,
2785 elfcpp::Elf_types
<32>::Elf_Addr address
,
2786 section_size_type view_size
)
2788 const elfcpp::Rel
<32, false> rel(preloc
);
2789 unsigned int r_type
= elfcpp::elf_r_type
<32>(rel
.get_r_info());
2791 if (this->skip_call_tls_get_addr_
)
2793 if ((r_type
!= elfcpp::R_386_PLT32
2794 && r_type
!= elfcpp::R_386_GOT32X
2795 && r_type
!= elfcpp::R_386_PC32
)
2797 || strcmp(gsym
->name(), "___tls_get_addr") != 0)
2799 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2800 _("missing expected TLS relocation"));
2801 this->skip_call_tls_get_addr_
= false;
2805 this->skip_call_tls_get_addr_
= false;
2813 const Sized_relobj_file
<32, false>* object
= relinfo
->object
;
2815 // Pick the value to use for symbols defined in shared objects.
2816 Symbol_value
<32> symval
;
2818 && gsym
->type() == elfcpp::STT_GNU_IFUNC
2819 && r_type
== elfcpp::R_386_32
2820 && gsym
->needs_dynamic_reloc(Scan::get_reference_flags(r_type
))
2821 && gsym
->can_use_relative_reloc(false)
2822 && !gsym
->is_from_dynobj()
2823 && !gsym
->is_undefined()
2824 && !gsym
->is_preemptible())
2826 // In this case we are generating a R_386_IRELATIVE reloc. We
2827 // want to use the real value of the symbol, not the PLT offset.
2829 else if (gsym
!= NULL
2830 && gsym
->use_plt_offset(Scan::get_reference_flags(r_type
)))
2832 symval
.set_output_value(target
->plt_address_for_global(gsym
));
2835 else if (gsym
== NULL
&& psymval
->is_ifunc_symbol())
2837 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
2838 if (object
->local_has_plt_offset(r_sym
))
2840 symval
.set_output_value(target
->plt_address_for_local(object
, r_sym
));
2849 case elfcpp::R_386_NONE
:
2850 case elfcpp::R_386_GNU_VTINHERIT
:
2851 case elfcpp::R_386_GNU_VTENTRY
:
2854 case elfcpp::R_386_32
:
2855 if (should_apply_static_reloc(gsym
, r_type
, true, output_section
))
2856 Relocate_functions
<32, false>::rel32(view
, object
, psymval
);
2859 case elfcpp::R_386_PC32
:
2860 if (should_apply_static_reloc(gsym
, r_type
, true, output_section
))
2861 Relocate_functions
<32, false>::pcrel32(view
, object
, psymval
, address
);
2864 case elfcpp::R_386_16
:
2865 if (should_apply_static_reloc(gsym
, r_type
, false, output_section
))
2866 Relocate_functions
<32, false>::rel16(view
, object
, psymval
);
2869 case elfcpp::R_386_PC16
:
2870 if (should_apply_static_reloc(gsym
, r_type
, false, output_section
))
2871 Relocate_functions
<32, false>::pcrel16(view
, object
, psymval
, address
);
2874 case elfcpp::R_386_8
:
2875 if (should_apply_static_reloc(gsym
, r_type
, false, output_section
))
2876 Relocate_functions
<32, false>::rel8(view
, object
, psymval
);
2879 case elfcpp::R_386_PC8
:
2880 if (should_apply_static_reloc(gsym
, r_type
, false, output_section
))
2881 Relocate_functions
<32, false>::pcrel8(view
, object
, psymval
, address
);
2884 case elfcpp::R_386_PLT32
:
2885 gold_assert(gsym
== NULL
2886 || gsym
->has_plt_offset()
2887 || gsym
->final_value_is_known()
2888 || (gsym
->is_defined()
2889 && !gsym
->is_from_dynobj()
2890 && !gsym
->is_preemptible()));
2891 Relocate_functions
<32, false>::pcrel32(view
, object
, psymval
, address
);
2894 case elfcpp::R_386_GOT32
:
2895 case elfcpp::R_386_GOT32X
:
2896 baseless
= (view
[-1] & 0xc7) == 0x5;
2897 // R_386_GOT32 and R_386_GOT32X don't work without base register
2898 // when generating a position-independent output file.
2900 && parameters
->options().output_is_position_independent())
2903 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2904 _("unexpected reloc %u against global symbol %s without base register in object file when generating a position-independent output file"),
2905 r_type
, gsym
->demangled_name().c_str());
2907 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2908 _("unexpected reloc %u against local symbol without base register in object file when generating a position-independent output file"),
2913 // mov foo@GOT(%reg), %reg
2915 // lea foo@GOTOFF(%reg), %reg
2917 if (rel
.get_r_offset() >= 2
2919 && ((gsym
== NULL
&& !psymval
->is_ifunc_symbol())
2921 && Target_i386::can_convert_mov_to_lea(gsym
))))
2924 elfcpp::Elf_types
<32>::Elf_Addr value
;
2925 value
= psymval
->value(object
, 0);
2926 // Don't subtract the .got.plt section address for baseless
2929 value
-= target
->got_plt_section()->address();
2930 Relocate_functions
<32, false>::rel32(view
, value
);
2934 // The GOT pointer points to the end of the GOT section.
2935 // We need to subtract the size of the GOT section to get
2936 // the actual offset to use in the relocation.
2937 unsigned int got_offset
= 0;
2940 gold_assert(gsym
->has_got_offset(GOT_TYPE_STANDARD
));
2941 got_offset
= (gsym
->got_offset(GOT_TYPE_STANDARD
)
2942 - target
->got_size());
2946 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
2947 gold_assert(object
->local_has_got_offset(r_sym
, GOT_TYPE_STANDARD
));
2948 got_offset
= (object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
)
2949 - target
->got_size());
2951 // Add the .got.plt section address for baseless addressing.
2953 got_offset
+= target
->got_plt_section()->address();
2954 Relocate_functions
<32, false>::rel32(view
, got_offset
);
2958 case elfcpp::R_386_GOTOFF
:
2960 elfcpp::Elf_types
<32>::Elf_Addr reladdr
;
2961 reladdr
= target
->got_plt_section()->address();
2962 Relocate_functions
<32, false>::pcrel32(view
, object
, psymval
, reladdr
);
2966 case elfcpp::R_386_GOTPC
:
2968 elfcpp::Elf_types
<32>::Elf_Addr value
;
2969 value
= target
->got_plt_section()->address();
2970 Relocate_functions
<32, false>::pcrel32(view
, value
, address
);
2974 case elfcpp::R_386_COPY
:
2975 case elfcpp::R_386_GLOB_DAT
:
2976 case elfcpp::R_386_JUMP_SLOT
:
2977 case elfcpp::R_386_RELATIVE
:
2978 case elfcpp::R_386_IRELATIVE
:
2979 // These are outstanding tls relocs, which are unexpected when
2981 case elfcpp::R_386_TLS_TPOFF
:
2982 case elfcpp::R_386_TLS_DTPMOD32
:
2983 case elfcpp::R_386_TLS_DTPOFF32
:
2984 case elfcpp::R_386_TLS_TPOFF32
:
2985 case elfcpp::R_386_TLS_DESC
:
2986 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2987 _("unexpected reloc %u in object file"),
2991 // These are initial tls relocs, which are expected when
2993 case elfcpp::R_386_TLS_GD
: // Global-dynamic
2994 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
2995 case elfcpp::R_386_TLS_DESC_CALL
:
2996 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
2997 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
2998 case elfcpp::R_386_TLS_IE
: // Initial-exec
2999 case elfcpp::R_386_TLS_IE_32
:
3000 case elfcpp::R_386_TLS_GOTIE
:
3001 case elfcpp::R_386_TLS_LE
: // Local-exec
3002 case elfcpp::R_386_TLS_LE_32
:
3003 this->relocate_tls(relinfo
, target
, relnum
, rel
, r_type
, gsym
, psymval
,
3004 view
, address
, view_size
);
3007 case elfcpp::R_386_32PLT
:
3008 case elfcpp::R_386_TLS_GD_32
:
3009 case elfcpp::R_386_TLS_GD_PUSH
:
3010 case elfcpp::R_386_TLS_GD_CALL
:
3011 case elfcpp::R_386_TLS_GD_POP
:
3012 case elfcpp::R_386_TLS_LDM_32
:
3013 case elfcpp::R_386_TLS_LDM_PUSH
:
3014 case elfcpp::R_386_TLS_LDM_CALL
:
3015 case elfcpp::R_386_TLS_LDM_POP
:
3016 case elfcpp::R_386_USED_BY_INTEL_200
:
3018 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
3019 _("unsupported reloc %u"),
3027 // Perform a TLS relocation.
3030 Target_i386::Relocate::relocate_tls(const Relocate_info
<32, false>* relinfo
,
3031 Target_i386
* target
,
3033 const elfcpp::Rel
<32, false>& rel
,
3034 unsigned int r_type
,
3035 const Sized_symbol
<32>* gsym
,
3036 const Symbol_value
<32>* psymval
,
3037 unsigned char* view
,
3038 elfcpp::Elf_types
<32>::Elf_Addr
,
3039 section_size_type view_size
)
3041 Output_segment
* tls_segment
= relinfo
->layout
->tls_segment();
3043 const Sized_relobj_file
<32, false>* object
= relinfo
->object
;
3045 elfcpp::Elf_types
<32>::Elf_Addr value
= psymval
->value(object
, 0);
3047 const bool is_final
= (gsym
== NULL
3048 ? !parameters
->options().shared()
3049 : gsym
->final_value_is_known());
3050 const tls::Tls_optimization optimized_type
3051 = Target_i386::optimize_tls_reloc(is_final
, r_type
);
3054 case elfcpp::R_386_TLS_GD
: // Global-dynamic
3055 if (optimized_type
== tls::TLSOPT_TO_LE
)
3057 if (tls_segment
== NULL
)
3059 gold_assert(parameters
->errors()->error_count() > 0
3060 || issue_undefined_symbol_error(gsym
));
3063 this->tls_gd_to_le(relinfo
, relnum
, tls_segment
,
3064 rel
, r_type
, value
, view
,
3070 unsigned int got_type
= (optimized_type
== tls::TLSOPT_TO_IE
3071 ? GOT_TYPE_TLS_NOFFSET
3072 : GOT_TYPE_TLS_PAIR
);
3073 unsigned int got_offset
;
3076 gold_assert(gsym
->has_got_offset(got_type
));
3077 got_offset
= gsym
->got_offset(got_type
) - target
->got_size();
3081 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
3082 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
3083 got_offset
= (object
->local_got_offset(r_sym
, got_type
)
3084 - target
->got_size());
3086 if (optimized_type
== tls::TLSOPT_TO_IE
)
3088 this->tls_gd_to_ie(relinfo
, relnum
, rel
, r_type
,
3089 got_offset
, view
, view_size
);
3092 else if (optimized_type
== tls::TLSOPT_NONE
)
3094 // Relocate the field with the offset of the pair of GOT
3096 Relocate_functions
<32, false>::rel32(view
, got_offset
);
3100 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
3101 _("unsupported reloc %u"),
3105 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
3106 case elfcpp::R_386_TLS_DESC_CALL
:
3107 this->local_dynamic_type_
= LOCAL_DYNAMIC_GNU
;
3108 if (optimized_type
== tls::TLSOPT_TO_LE
)
3110 if (tls_segment
== NULL
)
3112 gold_assert(parameters
->errors()->error_count() > 0
3113 || issue_undefined_symbol_error(gsym
));
3116 this->tls_desc_gd_to_le(relinfo
, relnum
, tls_segment
,
3117 rel
, r_type
, value
, view
,
3123 unsigned int got_type
= (optimized_type
== tls::TLSOPT_TO_IE
3124 ? GOT_TYPE_TLS_NOFFSET
3125 : GOT_TYPE_TLS_DESC
);
3126 unsigned int got_offset
= 0;
3127 if (r_type
== elfcpp::R_386_TLS_GOTDESC
3128 && optimized_type
== tls::TLSOPT_NONE
)
3130 // We created GOT entries in the .got.tlsdesc portion of
3131 // the .got.plt section, but the offset stored in the
3132 // symbol is the offset within .got.tlsdesc.
3133 got_offset
= (target
->got_size()
3134 + target
->got_plt_section()->data_size());
3138 gold_assert(gsym
->has_got_offset(got_type
));
3139 got_offset
+= gsym
->got_offset(got_type
) - target
->got_size();
3143 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
3144 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
3145 got_offset
+= (object
->local_got_offset(r_sym
, got_type
)
3146 - target
->got_size());
3148 if (optimized_type
== tls::TLSOPT_TO_IE
)
3150 this->tls_desc_gd_to_ie(relinfo
, relnum
, rel
, r_type
,
3151 got_offset
, view
, view_size
);
3154 else if (optimized_type
== tls::TLSOPT_NONE
)
3156 if (r_type
== elfcpp::R_386_TLS_GOTDESC
)
3158 // Relocate the field with the offset of the pair of GOT
3160 Relocate_functions
<32, false>::rel32(view
, got_offset
);
3165 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
3166 _("unsupported reloc %u"),
3170 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
3171 if (this->local_dynamic_type_
== LOCAL_DYNAMIC_SUN
)
3173 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
3174 _("both SUN and GNU model "
3175 "TLS relocations"));
3178 this->local_dynamic_type_
= LOCAL_DYNAMIC_GNU
;
3179 if (optimized_type
== tls::TLSOPT_TO_LE
)
3181 if (tls_segment
== NULL
)
3183 gold_assert(parameters
->errors()->error_count() > 0
3184 || issue_undefined_symbol_error(gsym
));
3187 this->tls_ld_to_le(relinfo
, relnum
, tls_segment
, rel
, r_type
,
3188 value
, view
, view_size
);
3191 else if (optimized_type
== tls::TLSOPT_NONE
)
3193 // Relocate the field with the offset of the GOT entry for
3194 // the module index.
3195 unsigned int got_offset
;
3196 got_offset
= (target
->got_mod_index_entry(NULL
, NULL
, NULL
)
3197 - target
->got_size());
3198 Relocate_functions
<32, false>::rel32(view
, got_offset
);
3201 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
3202 _("unsupported reloc %u"),
3206 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
3207 if (optimized_type
== tls::TLSOPT_TO_LE
)
3209 // This reloc can appear in debugging sections, in which
3210 // case we must not convert to local-exec. We decide what
3211 // to do based on whether the section is marked as
3212 // containing executable code. That is what the GNU linker
3214 elfcpp::Shdr
<32, false> shdr(relinfo
->data_shdr
);
3215 if ((shdr
.get_sh_flags() & elfcpp::SHF_EXECINSTR
) != 0)
3217 if (tls_segment
== NULL
)
3219 gold_assert(parameters
->errors()->error_count() > 0
3220 || issue_undefined_symbol_error(gsym
));
3223 value
-= tls_segment
->memsz();
3226 Relocate_functions
<32, false>::rel32(view
, value
);
3229 case elfcpp::R_386_TLS_IE
: // Initial-exec
3230 case elfcpp::R_386_TLS_GOTIE
:
3231 case elfcpp::R_386_TLS_IE_32
:
3232 if (optimized_type
== tls::TLSOPT_TO_LE
)
3234 if (tls_segment
== NULL
)
3236 gold_assert(parameters
->errors()->error_count() > 0
3237 || issue_undefined_symbol_error(gsym
));
3240 Target_i386::Relocate::tls_ie_to_le(relinfo
, relnum
, tls_segment
,
3241 rel
, r_type
, value
, view
,
3245 else if (optimized_type
== tls::TLSOPT_NONE
)
3247 // Relocate the field with the offset of the GOT entry for
3248 // the tp-relative offset of the symbol.
3249 unsigned int got_type
= (r_type
== elfcpp::R_386_TLS_IE_32
3250 ? GOT_TYPE_TLS_OFFSET
3251 : GOT_TYPE_TLS_NOFFSET
);
3252 unsigned int got_offset
;
3255 gold_assert(gsym
->has_got_offset(got_type
));
3256 got_offset
= gsym
->got_offset(got_type
);
3260 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
3261 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
3262 got_offset
= object
->local_got_offset(r_sym
, got_type
);
3264 // For the R_386_TLS_IE relocation, we need to apply the
3265 // absolute address of the GOT entry.
3266 if (r_type
== elfcpp::R_386_TLS_IE
)
3267 got_offset
+= target
->got_plt_section()->address();
3268 // All GOT offsets are relative to the end of the GOT.
3269 got_offset
-= target
->got_size();
3270 Relocate_functions
<32, false>::rel32(view
, got_offset
);
3273 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
3274 _("unsupported reloc %u"),
3278 case elfcpp::R_386_TLS_LE
: // Local-exec
3279 // If we're creating a shared library, a dynamic relocation will
3280 // have been created for this location, so do not apply it now.
3281 if (!parameters
->options().shared())
3283 if (tls_segment
== NULL
)
3285 gold_assert(parameters
->errors()->error_count() > 0
3286 || issue_undefined_symbol_error(gsym
));
3289 value
-= tls_segment
->memsz();
3290 Relocate_functions
<32, false>::rel32(view
, value
);
3294 case elfcpp::R_386_TLS_LE_32
:
3295 // If we're creating a shared library, a dynamic relocation will
3296 // have been created for this location, so do not apply it now.
3297 if (!parameters
->options().shared())
3299 if (tls_segment
== NULL
)
3301 gold_assert(parameters
->errors()->error_count() > 0
3302 || issue_undefined_symbol_error(gsym
));
3305 value
= tls_segment
->memsz() - value
;
3306 Relocate_functions
<32, false>::rel32(view
, value
);
3312 // Do a relocation in which we convert a TLS General-Dynamic to a
3316 Target_i386::Relocate::tls_gd_to_le(const Relocate_info
<32, false>* relinfo
,
3318 Output_segment
* tls_segment
,
3319 const elfcpp::Rel
<32, false>& rel
,
3321 elfcpp::Elf_types
<32>::Elf_Addr value
,
3322 unsigned char* view
,
3323 section_size_type view_size
)
3325 // leal foo(,%ebx,1),%eax; call ___tls_get_addr@PLT
3326 // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
3327 // leal foo(%ebx),%eax; call ___tls_get_addr@PLT
3328 // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
3329 // leal foo(%reg),%eax; call *___tls_get_addr@GOT(%reg)
3330 // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
3332 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
3333 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 9);
3335 unsigned char op1
= view
[-1];
3336 unsigned char op2
= view
[-2];
3337 unsigned char op3
= view
[4];
3339 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3340 op2
== 0x8d || op2
== 0x04);
3341 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3342 op3
== 0xe8 || op3
== 0xff);
3348 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -3);
3349 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[-3] == 0x8d);
3350 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3351 ((op1
& 0xc7) == 0x05 && op1
!= (4 << 3)));
3352 memcpy(view
- 3, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
3356 unsigned char reg
= op1
& 7;
3357 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3358 ((op1
& 0xf8) == 0x80
3361 && (op3
== 0xe8 || (view
[5] & 0x7) == reg
)));
3363 || (rel
.get_r_offset() + 9 < view_size
3364 && view
[9] == 0x90))
3366 // There is an indirect call or a trailing nop. Use the size
3368 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
3373 // Use the five byte subl.
3374 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
3378 value
= tls_segment
->memsz() - value
;
3379 Relocate_functions
<32, false>::rel32(view
+ roff
, value
);
3381 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3383 this->skip_call_tls_get_addr_
= true;
3386 // Do a relocation in which we convert a TLS General-Dynamic to an
3390 Target_i386::Relocate::tls_gd_to_ie(const Relocate_info
<32, false>* relinfo
,
3392 const elfcpp::Rel
<32, false>& rel
,
3394 elfcpp::Elf_types
<32>::Elf_Addr value
,
3395 unsigned char* view
,
3396 section_size_type view_size
)
3398 // leal foo(,%ebx,1),%eax; call ___tls_get_addr@PLT
3399 // ==> movl %gs:0,%eax; addl foo@gotntpoff(%ebx),%eax
3400 // leal foo(%ebx),%eax; call ___tls_get_addr@PLT; nop
3401 // ==> movl %gs:0,%eax; addl foo@gotntpoff(%ebx),%eax
3402 // leal foo(%reg),%eax; call *___tls_get_addr@GOT(%reg)
3403 // ==> movl %gs:0,%eax; addl foo@gotntpoff(%reg),%eax
3405 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
3406 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 9);
3408 unsigned char op1
= view
[-1];
3409 unsigned char op2
= view
[-2];
3410 unsigned char op3
= view
[4];
3412 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3413 op2
== 0x8d || op2
== 0x04);
3414 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3415 op3
== 0xe8 || op3
== 0xff);
3421 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -3);
3422 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[-3] == 0x8d);
3423 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3424 ((op1
& 0xc7) == 0x05 && op1
!= (4 << 3)));
3429 unsigned char reg
= op1
& 7;
3430 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 10);
3431 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3432 ((op1
& 0xf8) == 0x80
3435 && ((op3
== 0xe8 && view
[9] == 0x90)
3436 || (view
[5] & 0x7) == reg
)));
3440 memcpy(view
+ roff
- 8, "\x65\xa1\0\0\0\0\x03\x83\0\0\0", 12);
3441 Relocate_functions
<32, false>::rel32(view
+ roff
, value
);
3443 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3445 this->skip_call_tls_get_addr_
= true;
3448 // Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL
3449 // General-Dynamic to a Local-Exec.
3452 Target_i386::Relocate::tls_desc_gd_to_le(
3453 const Relocate_info
<32, false>* relinfo
,
3455 Output_segment
* tls_segment
,
3456 const elfcpp::Rel
<32, false>& rel
,
3457 unsigned int r_type
,
3458 elfcpp::Elf_types
<32>::Elf_Addr value
,
3459 unsigned char* view
,
3460 section_size_type view_size
)
3462 if (r_type
== elfcpp::R_386_TLS_GOTDESC
)
3464 // leal foo@TLSDESC(%ebx), %eax
3465 // ==> leal foo@NTPOFF, %eax
3466 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
3467 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
3468 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3469 view
[-2] == 0x8d && view
[-1] == 0x83);
3471 value
-= tls_segment
->memsz();
3472 Relocate_functions
<32, false>::rel32(view
, value
);
3476 // call *foo@TLSCALL(%eax)
3478 gold_assert(r_type
== elfcpp::R_386_TLS_DESC_CALL
);
3479 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 2);
3480 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3481 view
[0] == 0xff && view
[1] == 0x10);
3487 // Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL
3488 // General-Dynamic to an Initial-Exec.
3491 Target_i386::Relocate::tls_desc_gd_to_ie(
3492 const Relocate_info
<32, false>* relinfo
,
3494 const elfcpp::Rel
<32, false>& rel
,
3495 unsigned int r_type
,
3496 elfcpp::Elf_types
<32>::Elf_Addr value
,
3497 unsigned char* view
,
3498 section_size_type view_size
)
3500 if (r_type
== elfcpp::R_386_TLS_GOTDESC
)
3502 // leal foo@TLSDESC(%ebx), %eax
3503 // ==> movl foo@GOTNTPOFF(%ebx), %eax
3504 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
3505 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
3506 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3507 view
[-2] == 0x8d && view
[-1] == 0x83);
3509 Relocate_functions
<32, false>::rel32(view
, value
);
3513 // call *foo@TLSCALL(%eax)
3515 gold_assert(r_type
== elfcpp::R_386_TLS_DESC_CALL
);
3516 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 2);
3517 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3518 view
[0] == 0xff && view
[1] == 0x10);
3524 // Do a relocation in which we convert a TLS Local-Dynamic to a
3528 Target_i386::Relocate::tls_ld_to_le(const Relocate_info
<32, false>* relinfo
,
3531 const elfcpp::Rel
<32, false>& rel
,
3533 elfcpp::Elf_types
<32>::Elf_Addr
,
3534 unsigned char* view
,
3535 section_size_type view_size
)
3537 // leal foo(%ebx), %eax; call ___tls_get_addr@PLT
3538 // ==> movl %gs:0,%eax; nop; leal 0(%esi,1),%esi
3539 // leal foo(%reg), %eax; call call *___tls_get_addr@GOT(%reg)
3540 // ==> movl %gs:0,%eax; leal (%esi),%esi
3542 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
3544 unsigned char op1
= view
[-1];
3545 unsigned char op2
= view
[-2];
3546 unsigned char op3
= view
[4];
3548 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3549 op3
== 0xe8 || op3
== 0xff);
3550 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
,
3551 op3
== 0xe8 ? 9 : 10);
3553 // FIXME: Does this test really always pass?
3554 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), op2
== 0x8d);
3556 unsigned char reg
= op1
& 7;
3557 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3558 ((op1
& 0xf8) == 0x80
3561 && (op3
== 0xe8 || (view
[5] & 0x7) == reg
)));
3564 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x90\x8d\x74\x26\0", 11);
3566 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x8d\xb6\0\0\0\0", 12);
3568 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3570 this->skip_call_tls_get_addr_
= true;
3573 // Do a relocation in which we convert a TLS Initial-Exec to a
3577 Target_i386::Relocate::tls_ie_to_le(const Relocate_info
<32, false>* relinfo
,
3579 Output_segment
* tls_segment
,
3580 const elfcpp::Rel
<32, false>& rel
,
3581 unsigned int r_type
,
3582 elfcpp::Elf_types
<32>::Elf_Addr value
,
3583 unsigned char* view
,
3584 section_size_type view_size
)
3586 // We have to actually change the instructions, which means that we
3587 // need to examine the opcodes to figure out which instruction we
3589 if (r_type
== elfcpp::R_386_TLS_IE
)
3591 // movl %gs:XX,%eax ==> movl $YY,%eax
3592 // movl %gs:XX,%reg ==> movl $YY,%reg
3593 // addl %gs:XX,%reg ==> addl $YY,%reg
3594 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -1);
3595 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
3597 unsigned char op1
= view
[-1];
3600 // movl XX,%eax ==> movl $YY,%eax
3605 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
3607 unsigned char op2
= view
[-2];
3610 // movl XX,%reg ==> movl $YY,%reg
3611 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3612 (op1
& 0xc7) == 0x05);
3614 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
3616 else if (op2
== 0x03)
3618 // addl XX,%reg ==> addl $YY,%reg
3619 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3620 (op1
& 0xc7) == 0x05);
3622 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
3625 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), 0);
3630 // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2
3631 // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2
3632 // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2
3633 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
3634 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
3636 unsigned char op1
= view
[-1];
3637 unsigned char op2
= view
[-2];
3638 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3639 (op1
& 0xc0) == 0x80 && (op1
& 7) != 4);
3642 // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2
3644 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
3646 else if (op2
== 0x2b)
3648 // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2
3650 view
[-1] = 0xe8 | ((op1
>> 3) & 7);
3652 else if (op2
== 0x03)
3654 // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2
3656 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
3659 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), 0);
3662 value
= tls_segment
->memsz() - value
;
3663 if (r_type
== elfcpp::R_386_TLS_IE
|| r_type
== elfcpp::R_386_TLS_GOTIE
)
3666 Relocate_functions
<32, false>::rel32(view
, value
);
3669 // Relocate section data.
3672 Target_i386::relocate_section(const Relocate_info
<32, false>* relinfo
,
3673 unsigned int sh_type
,
3674 const unsigned char* prelocs
,
3676 Output_section
* output_section
,
3677 bool needs_special_offset_handling
,
3678 unsigned char* view
,
3679 elfcpp::Elf_types
<32>::Elf_Addr address
,
3680 section_size_type view_size
,
3681 const Reloc_symbol_changes
* reloc_symbol_changes
)
3683 gold_assert(sh_type
== elfcpp::SHT_REL
);
3685 gold::relocate_section
<32, false, Target_i386
, Relocate
,
3686 gold::Default_comdat_behavior
, Classify_reloc
>(
3692 needs_special_offset_handling
,
3696 reloc_symbol_changes
);
3699 // Return the size of a relocation while scanning during a relocatable
3703 Target_i386::Classify_reloc::get_size_for_reloc(
3704 unsigned int r_type
,
3709 case elfcpp::R_386_NONE
:
3710 case elfcpp::R_386_GNU_VTINHERIT
:
3711 case elfcpp::R_386_GNU_VTENTRY
:
3712 case elfcpp::R_386_TLS_GD
: // Global-dynamic
3713 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
3714 case elfcpp::R_386_TLS_DESC_CALL
:
3715 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
3716 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
3717 case elfcpp::R_386_TLS_IE
: // Initial-exec
3718 case elfcpp::R_386_TLS_IE_32
:
3719 case elfcpp::R_386_TLS_GOTIE
:
3720 case elfcpp::R_386_TLS_LE
: // Local-exec
3721 case elfcpp::R_386_TLS_LE_32
:
3724 case elfcpp::R_386_32
:
3725 case elfcpp::R_386_PC32
:
3726 case elfcpp::R_386_GOT32
:
3727 case elfcpp::R_386_GOT32X
:
3728 case elfcpp::R_386_PLT32
:
3729 case elfcpp::R_386_GOTOFF
:
3730 case elfcpp::R_386_GOTPC
:
3733 case elfcpp::R_386_16
:
3734 case elfcpp::R_386_PC16
:
3737 case elfcpp::R_386_8
:
3738 case elfcpp::R_386_PC8
:
3741 // These are relocations which should only be seen by the
3742 // dynamic linker, and should never be seen here.
3743 case elfcpp::R_386_COPY
:
3744 case elfcpp::R_386_GLOB_DAT
:
3745 case elfcpp::R_386_JUMP_SLOT
:
3746 case elfcpp::R_386_RELATIVE
:
3747 case elfcpp::R_386_IRELATIVE
:
3748 case elfcpp::R_386_TLS_TPOFF
:
3749 case elfcpp::R_386_TLS_DTPMOD32
:
3750 case elfcpp::R_386_TLS_DTPOFF32
:
3751 case elfcpp::R_386_TLS_TPOFF32
:
3752 case elfcpp::R_386_TLS_DESC
:
3753 object
->error(_("unexpected reloc %u in object file"), r_type
);
3756 case elfcpp::R_386_32PLT
:
3757 case elfcpp::R_386_TLS_GD_32
:
3758 case elfcpp::R_386_TLS_GD_PUSH
:
3759 case elfcpp::R_386_TLS_GD_CALL
:
3760 case elfcpp::R_386_TLS_GD_POP
:
3761 case elfcpp::R_386_TLS_LDM_32
:
3762 case elfcpp::R_386_TLS_LDM_PUSH
:
3763 case elfcpp::R_386_TLS_LDM_CALL
:
3764 case elfcpp::R_386_TLS_LDM_POP
:
3765 case elfcpp::R_386_USED_BY_INTEL_200
:
3767 object
->error(_("unsupported reloc %u in object file"), r_type
);
3772 // Scan the relocs during a relocatable link.
3775 Target_i386::scan_relocatable_relocs(Symbol_table
* symtab
,
3777 Sized_relobj_file
<32, false>* object
,
3778 unsigned int data_shndx
,
3779 unsigned int sh_type
,
3780 const unsigned char* prelocs
,
3782 Output_section
* output_section
,
3783 bool needs_special_offset_handling
,
3784 size_t local_symbol_count
,
3785 const unsigned char* plocal_symbols
,
3786 Relocatable_relocs
* rr
)
3788 typedef gold::Default_scan_relocatable_relocs
<Classify_reloc
>
3789 Scan_relocatable_relocs
;
3791 gold_assert(sh_type
== elfcpp::SHT_REL
);
3793 gold::scan_relocatable_relocs
<32, false, Scan_relocatable_relocs
>(
3801 needs_special_offset_handling
,
3807 // Scan the relocs for --emit-relocs.
3810 Target_i386::emit_relocs_scan(Symbol_table
* symtab
,
3812 Sized_relobj_file
<32, false>* object
,
3813 unsigned int data_shndx
,
3814 unsigned int sh_type
,
3815 const unsigned char* prelocs
,
3817 Output_section
* output_section
,
3818 bool needs_special_offset_handling
,
3819 size_t local_symbol_count
,
3820 const unsigned char* plocal_syms
,
3821 Relocatable_relocs
* rr
)
3823 typedef gold::Default_classify_reloc
<elfcpp::SHT_REL
, 32, false>
3825 typedef gold::Default_emit_relocs_strategy
<Classify_reloc
>
3826 Emit_relocs_strategy
;
3828 gold_assert(sh_type
== elfcpp::SHT_REL
);
3830 gold::scan_relocatable_relocs
<32, false, Emit_relocs_strategy
>(
3838 needs_special_offset_handling
,
3844 // Emit relocations for a section.
3847 Target_i386::relocate_relocs(
3848 const Relocate_info
<32, false>* relinfo
,
3849 unsigned int sh_type
,
3850 const unsigned char* prelocs
,
3852 Output_section
* output_section
,
3853 elfcpp::Elf_types
<32>::Elf_Off offset_in_output_section
,
3854 unsigned char* view
,
3855 elfcpp::Elf_types
<32>::Elf_Addr view_address
,
3856 section_size_type view_size
,
3857 unsigned char* reloc_view
,
3858 section_size_type reloc_view_size
)
3860 gold_assert(sh_type
== elfcpp::SHT_REL
);
3862 gold::relocate_relocs
<32, false, Classify_reloc
>(
3867 offset_in_output_section
,
3875 // Return the value to use for a dynamic which requires special
3876 // treatment. This is how we support equality comparisons of function
3877 // pointers across shared library boundaries, as described in the
3878 // processor specific ABI supplement.
3881 Target_i386::do_dynsym_value(const Symbol
* gsym
) const
3883 gold_assert(gsym
->is_from_dynobj() && gsym
->has_plt_offset());
3884 return this->plt_address_for_global(gsym
);
3887 // Return a string used to fill a code section with nops to take up
3888 // the specified length.
3891 Target_i386::do_code_fill(section_size_type length
) const
3895 // Build a jmp instruction to skip over the bytes.
3896 unsigned char jmp
[5];
3898 elfcpp::Swap_unaligned
<32, false>::writeval(jmp
+ 1, length
- 5);
3899 return (std::string(reinterpret_cast<char*>(&jmp
[0]), 5)
3900 + std::string(length
- 5, static_cast<char>(0x90)));
3903 // Nop sequences of various lengths.
3904 const char nop1
[1] = { '\x90' }; // nop
3905 const char nop2
[2] = { '\x66', '\x90' }; // xchg %ax %ax
3906 const char nop3
[3] = { '\x8d', '\x76', '\x00' }; // leal 0(%esi),%esi
3907 const char nop4
[4] = { '\x8d', '\x74', '\x26', // leal 0(%esi,1),%esi
3909 const char nop5
[5] = { '\x90', '\x8d', '\x74', // nop
3910 '\x26', '\x00' }; // leal 0(%esi,1),%esi
3911 const char nop6
[6] = { '\x8d', '\xb6', '\x00', // leal 0L(%esi),%esi
3912 '\x00', '\x00', '\x00' };
3913 const char nop7
[7] = { '\x8d', '\xb4', '\x26', // leal 0L(%esi,1),%esi
3914 '\x00', '\x00', '\x00',
3916 const char nop8
[8] = { '\x90', '\x8d', '\xb4', // nop
3917 '\x26', '\x00', '\x00', // leal 0L(%esi,1),%esi
3919 const char nop9
[9] = { '\x89', '\xf6', '\x8d', // movl %esi,%esi
3920 '\xbc', '\x27', '\x00', // leal 0L(%edi,1),%edi
3921 '\x00', '\x00', '\x00' };
3922 const char nop10
[10] = { '\x8d', '\x76', '\x00', // leal 0(%esi),%esi
3923 '\x8d', '\xbc', '\x27', // leal 0L(%edi,1),%edi
3924 '\x00', '\x00', '\x00',
3926 const char nop11
[11] = { '\x8d', '\x74', '\x26', // leal 0(%esi,1),%esi
3927 '\x00', '\x8d', '\xbc', // leal 0L(%edi,1),%edi
3928 '\x27', '\x00', '\x00',
3930 const char nop12
[12] = { '\x8d', '\xb6', '\x00', // leal 0L(%esi),%esi
3931 '\x00', '\x00', '\x00', // leal 0L(%edi),%edi
3932 '\x8d', '\xbf', '\x00',
3933 '\x00', '\x00', '\x00' };
3934 const char nop13
[13] = { '\x8d', '\xb6', '\x00', // leal 0L(%esi),%esi
3935 '\x00', '\x00', '\x00', // leal 0L(%edi,1),%edi
3936 '\x8d', '\xbc', '\x27',
3937 '\x00', '\x00', '\x00',
3939 const char nop14
[14] = { '\x8d', '\xb4', '\x26', // leal 0L(%esi,1),%esi
3940 '\x00', '\x00', '\x00', // leal 0L(%edi,1),%edi
3941 '\x00', '\x8d', '\xbc',
3942 '\x27', '\x00', '\x00',
3944 const char nop15
[15] = { '\xeb', '\x0d', '\x90', // jmp .+15
3945 '\x90', '\x90', '\x90', // nop,nop,nop,...
3946 '\x90', '\x90', '\x90',
3947 '\x90', '\x90', '\x90',
3948 '\x90', '\x90', '\x90' };
3950 const char* nops
[16] = {
3952 nop1
, nop2
, nop3
, nop4
, nop5
, nop6
, nop7
,
3953 nop8
, nop9
, nop10
, nop11
, nop12
, nop13
, nop14
, nop15
3956 return std::string(nops
[length
], length
);
3959 // Return the value to use for the base of a DW_EH_PE_datarel offset
3960 // in an FDE. Solaris and SVR4 use DW_EH_PE_datarel because their
3961 // assembler can not write out the difference between two labels in
3962 // different sections, so instead of using a pc-relative value they
3963 // use an offset from the GOT.
3966 Target_i386::do_ehframe_datarel_base() const
3968 gold_assert(this->global_offset_table_
!= NULL
);
3969 Symbol
* sym
= this->global_offset_table_
;
3970 Sized_symbol
<32>* ssym
= static_cast<Sized_symbol
<32>*>(sym
);
3971 return ssym
->value();
3974 // Return whether SYM should be treated as a call to a non-split
3975 // function. We don't want that to be true of a call to a
3976 // get_pc_thunk function.
3979 Target_i386::do_is_call_to_non_split(const Symbol
* sym
,
3980 const unsigned char*,
3981 const unsigned char*,
3982 section_size_type
) const
3984 return (sym
->type() == elfcpp::STT_FUNC
3985 && !is_prefix_of("__i686.get_pc_thunk.", sym
->name()));
3988 // FNOFFSET in section SHNDX in OBJECT is the start of a function
3989 // compiled with -fsplit-stack. The function calls non-split-stack
3990 // code. We have to change the function so that it always ensures
3991 // that it has enough stack space to run some random function.
3994 Target_i386::do_calls_non_split(Relobj
* object
, unsigned int shndx
,
3995 section_offset_type fnoffset
,
3996 section_size_type fnsize
,
3997 const unsigned char*,
3999 unsigned char* view
,
4000 section_size_type view_size
,
4002 std::string
* to
) const
4004 // The function starts with a comparison of the stack pointer and a
4005 // field in the TCB. This is followed by a jump.
4008 if (this->match_view(view
, view_size
, fnoffset
, "\x65\x3b\x25", 3)
4011 // We will call __morestack if the carry flag is set after this
4012 // comparison. We turn the comparison into an stc instruction
4014 view
[fnoffset
] = '\xf9';
4015 this->set_view_to_nop(view
, view_size
, fnoffset
+ 1, 6);
4017 // lea NN(%esp),%ecx
4018 // lea NN(%esp),%edx
4019 else if ((this->match_view(view
, view_size
, fnoffset
, "\x8d\x8c\x24", 3)
4020 || this->match_view(view
, view_size
, fnoffset
, "\x8d\x94\x24", 3))
4023 // This is loading an offset from the stack pointer for a
4024 // comparison. The offset is negative, so we decrease the
4025 // offset by the amount of space we need for the stack. This
4026 // means we will avoid calling __morestack if there happens to
4027 // be plenty of space on the stack already.
4028 unsigned char* pval
= view
+ fnoffset
+ 3;
4029 uint32_t val
= elfcpp::Swap_unaligned
<32, false>::readval(pval
);
4030 val
-= parameters
->options().split_stack_adjust_size();
4031 elfcpp::Swap_unaligned
<32, false>::writeval(pval
, val
);
4035 if (!object
->has_no_split_stack())
4036 object
->error(_("failed to match split-stack sequence at "
4037 "section %u offset %0zx"),
4038 shndx
, static_cast<size_t>(fnoffset
));
4042 // We have to change the function so that it calls
4043 // __morestack_non_split instead of __morestack. The former will
4044 // allocate additional stack space.
4045 *from
= "__morestack";
4046 *to
= "__morestack_non_split";
4049 // The selector for i386 object files. Note this is never instantiated
4050 // directly. It's only used in Target_selector_i386_nacl, below.
4052 class Target_selector_i386
: public Target_selector_freebsd
4055 Target_selector_i386()
4056 : Target_selector_freebsd(elfcpp::EM_386
, 32, false,
4057 "elf32-i386", "elf32-i386-freebsd",
4062 do_instantiate_target()
4063 { return new Target_i386(); }
4066 // NaCl variant. It uses different PLT contents.
4068 class Output_data_plt_i386_nacl
: public Output_data_plt_i386
4071 Output_data_plt_i386_nacl(Layout
* layout
,
4072 Output_data_got_plt_i386
* got_plt
,
4073 Output_data_space
* got_irelative
)
4074 : Output_data_plt_i386(layout
, plt_entry_size
, got_plt
, got_irelative
)
4078 virtual unsigned int
4079 do_get_plt_entry_size() const
4080 { return plt_entry_size
; }
4083 do_add_eh_frame(Layout
* layout
)
4085 layout
->add_eh_frame_for_plt(this, plt_eh_frame_cie
, plt_eh_frame_cie_size
,
4086 plt_eh_frame_fde
, plt_eh_frame_fde_size
);
4089 // The size of an entry in the PLT.
4090 static const int plt_entry_size
= 64;
4092 // The .eh_frame unwind information for the PLT.
4093 static const int plt_eh_frame_fde_size
= 32;
4094 static const unsigned char plt_eh_frame_fde
[plt_eh_frame_fde_size
];
4097 class Output_data_plt_i386_nacl_exec
: public Output_data_plt_i386_nacl
4100 Output_data_plt_i386_nacl_exec(Layout
* layout
,
4101 Output_data_got_plt_i386
* got_plt
,
4102 Output_data_space
* got_irelative
)
4103 : Output_data_plt_i386_nacl(layout
, got_plt
, got_irelative
)
4108 do_fill_first_plt_entry(unsigned char* pov
,
4109 elfcpp::Elf_types
<32>::Elf_Addr got_address
);
4111 virtual unsigned int
4112 do_fill_plt_entry(unsigned char* pov
,
4113 elfcpp::Elf_types
<32>::Elf_Addr got_address
,
4114 unsigned int got_offset
,
4115 unsigned int plt_offset
,
4116 unsigned int plt_rel_offset
);
4119 // The first entry in the PLT for an executable.
4120 static const unsigned char first_plt_entry
[plt_entry_size
];
4122 // Other entries in the PLT for an executable.
4123 static const unsigned char plt_entry
[plt_entry_size
];
4126 class Output_data_plt_i386_nacl_dyn
: public Output_data_plt_i386_nacl
4129 Output_data_plt_i386_nacl_dyn(Layout
* layout
,
4130 Output_data_got_plt_i386
* got_plt
,
4131 Output_data_space
* got_irelative
)
4132 : Output_data_plt_i386_nacl(layout
, got_plt
, got_irelative
)
4137 do_fill_first_plt_entry(unsigned char* pov
, elfcpp::Elf_types
<32>::Elf_Addr
);
4139 virtual unsigned int
4140 do_fill_plt_entry(unsigned char* pov
,
4141 elfcpp::Elf_types
<32>::Elf_Addr
,
4142 unsigned int got_offset
,
4143 unsigned int plt_offset
,
4144 unsigned int plt_rel_offset
);
4147 // The first entry in the PLT for a shared object.
4148 static const unsigned char first_plt_entry
[plt_entry_size
];
4150 // Other entries in the PLT for a shared object.
4151 static const unsigned char plt_entry
[plt_entry_size
];
4154 class Target_i386_nacl
: public Target_i386
4158 : Target_i386(&i386_nacl_info
)
4162 virtual Output_data_plt_i386
*
4163 do_make_data_plt(Layout
* layout
,
4164 Output_data_got_plt_i386
* got_plt
,
4165 Output_data_space
* got_irelative
,
4169 return new Output_data_plt_i386_nacl_dyn(layout
, got_plt
, got_irelative
);
4171 return new Output_data_plt_i386_nacl_exec(layout
, got_plt
, got_irelative
);
4175 do_code_fill(section_size_type length
) const;
4178 static const Target::Target_info i386_nacl_info
;
4181 const Target::Target_info
Target_i386_nacl::i386_nacl_info
=
4184 false, // is_big_endian
4185 elfcpp::EM_386
, // machine_code
4186 false, // has_make_symbol
4187 false, // has_resolve
4188 true, // has_code_fill
4189 true, // is_default_stack_executable
4190 true, // can_icf_inline_merge_sections
4192 "/lib/ld-nacl-x86-32.so.1", // dynamic_linker
4193 0x20000, // default_text_segment_address
4194 0x10000, // abi_pagesize (overridable by -z max-page-size)
4195 0x10000, // common_pagesize (overridable by -z common-page-size)
4196 true, // isolate_execinstr
4197 0x10000000, // rosegment_gap
4198 elfcpp::SHN_UNDEF
, // small_common_shndx
4199 elfcpp::SHN_UNDEF
, // large_common_shndx
4200 0, // small_common_section_flags
4201 0, // large_common_section_flags
4202 NULL
, // attributes_section
4203 NULL
, // attributes_vendor
4204 "_start", // entry_symbol_name
4205 32, // hash_entry_size
4206 elfcpp::SHT_PROGBITS
, // unwind_section_type
4209 #define NACLMASK 0xe0 // 32-byte alignment mask
4212 Output_data_plt_i386_nacl_exec::first_plt_entry
[plt_entry_size
] =
4214 0xff, 0x35, // pushl contents of memory address
4215 0, 0, 0, 0, // replaced with address of .got + 4
4216 0x8b, 0x0d, // movl contents of address, %ecx
4217 0, 0, 0, 0, // replaced with address of .got + 8
4218 0x83, 0xe1, NACLMASK
, // andl $NACLMASK, %ecx
4219 0xff, 0xe1, // jmp *%ecx
4220 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4221 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4222 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4223 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4224 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4225 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4226 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4227 0x90, 0x90, 0x90, 0x90, 0x90
4231 Output_data_plt_i386_nacl_exec::do_fill_first_plt_entry(
4233 elfcpp::Elf_types
<32>::Elf_Addr got_address
)
4235 memcpy(pov
, first_plt_entry
, plt_entry_size
);
4236 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2, got_address
+ 4);
4237 elfcpp::Swap
<32, false>::writeval(pov
+ 8, got_address
+ 8);
4240 // The first entry in the PLT for a shared object.
4243 Output_data_plt_i386_nacl_dyn::first_plt_entry
[plt_entry_size
] =
4245 0xff, 0xb3, 4, 0, 0, 0, // pushl 4(%ebx)
4246 0x8b, 0x4b, 0x08, // mov 0x8(%ebx), %ecx
4247 0x83, 0xe1, NACLMASK
, // andl $NACLMASK, %ecx
4248 0xff, 0xe1, // jmp *%ecx
4249 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4250 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4251 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4252 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4253 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4254 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4255 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4256 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4257 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4258 0x90, 0x90, 0x90, 0x90, 0x90 // nops
4262 Output_data_plt_i386_nacl_dyn::do_fill_first_plt_entry(
4264 elfcpp::Elf_types
<32>::Elf_Addr
)
4266 memcpy(pov
, first_plt_entry
, plt_entry_size
);
4269 // Subsequent entries in the PLT for an executable.
4272 Output_data_plt_i386_nacl_exec::plt_entry
[plt_entry_size
] =
4274 0x8b, 0x0d, // movl contents of address, %ecx */
4275 0, 0, 0, 0, // replaced with address of symbol in .got
4276 0x83, 0xe1, NACLMASK
, // andl $NACLMASK, %ecx
4277 0xff, 0xe1, // jmp *%ecx
4279 // Pad to the next 32-byte boundary with nop instructions.
4281 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4282 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4284 // Lazy GOT entries point here (32-byte aligned).
4285 0x68, // pushl immediate
4286 0, 0, 0, 0, // replaced with offset into relocation table
4287 0xe9, // jmp relative
4288 0, 0, 0, 0, // replaced with offset to start of .plt
4290 // Pad to the next 32-byte boundary with nop instructions.
4291 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4292 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4297 Output_data_plt_i386_nacl_exec::do_fill_plt_entry(
4299 elfcpp::Elf_types
<32>::Elf_Addr got_address
,
4300 unsigned int got_offset
,
4301 unsigned int plt_offset
,
4302 unsigned int plt_rel_offset
)
4304 memcpy(pov
, plt_entry
, plt_entry_size
);
4305 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
4306 got_address
+ got_offset
);
4307 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 33, plt_rel_offset
);
4308 elfcpp::Swap
<32, false>::writeval(pov
+ 38, - (plt_offset
+ 38 + 4));
4312 // Subsequent entries in the PLT for a shared object.
4315 Output_data_plt_i386_nacl_dyn::plt_entry
[plt_entry_size
] =
4317 0x8b, 0x8b, // movl offset(%ebx), %ecx
4318 0, 0, 0, 0, // replaced with offset of symbol in .got
4319 0x83, 0xe1, 0xe0, // andl $NACLMASK, %ecx
4320 0xff, 0xe1, // jmp *%ecx
4322 // Pad to the next 32-byte boundary with nop instructions.
4324 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4325 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4327 // Lazy GOT entries point here (32-byte aligned).
4328 0x68, // pushl immediate
4329 0, 0, 0, 0, // replaced with offset into relocation table.
4330 0xe9, // jmp relative
4331 0, 0, 0, 0, // replaced with offset to start of .plt.
4333 // Pad to the next 32-byte boundary with nop instructions.
4334 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4335 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4340 Output_data_plt_i386_nacl_dyn::do_fill_plt_entry(
4342 elfcpp::Elf_types
<32>::Elf_Addr
,
4343 unsigned int got_offset
,
4344 unsigned int plt_offset
,
4345 unsigned int plt_rel_offset
)
4347 memcpy(pov
, plt_entry
, plt_entry_size
);
4348 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2, got_offset
);
4349 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 33, plt_rel_offset
);
4350 elfcpp::Swap
<32, false>::writeval(pov
+ 38, - (plt_offset
+ 38 + 4));
4355 Output_data_plt_i386_nacl::plt_eh_frame_fde
[plt_eh_frame_fde_size
] =
4357 0, 0, 0, 0, // Replaced with offset to .plt.
4358 0, 0, 0, 0, // Replaced with size of .plt.
4359 0, // Augmentation size.
4360 elfcpp::DW_CFA_def_cfa_offset
, 8, // DW_CFA_def_cfa_offset: 8.
4361 elfcpp::DW_CFA_advance_loc
+ 6, // Advance 6 to __PLT__ + 6.
4362 elfcpp::DW_CFA_def_cfa_offset
, 12, // DW_CFA_def_cfa_offset: 12.
4363 elfcpp::DW_CFA_advance_loc
+ 58, // Advance 58 to __PLT__ + 64.
4364 elfcpp::DW_CFA_def_cfa_expression
, // DW_CFA_def_cfa_expression.
4365 13, // Block length.
4366 elfcpp::DW_OP_breg4
, 4, // Push %esp + 4.
4367 elfcpp::DW_OP_breg8
, 0, // Push %eip.
4368 elfcpp::DW_OP_const1u
, 63, // Push 0x3f.
4369 elfcpp::DW_OP_and
, // & (%eip & 0x3f).
4370 elfcpp::DW_OP_const1u
, 37, // Push 0x25.
4371 elfcpp::DW_OP_ge
, // >= ((%eip & 0x3f) >= 0x25)
4372 elfcpp::DW_OP_lit2
, // Push 2.
4373 elfcpp::DW_OP_shl
, // << (((%eip & 0x3f) >= 0x25) << 2)
4374 elfcpp::DW_OP_plus
, // + ((((%eip&0x3f)>=0x25)<<2)+%esp+4
4375 elfcpp::DW_CFA_nop
, // Align to 32 bytes.
4379 // Return a string used to fill a code section with nops.
4380 // For NaCl, long NOPs are only valid if they do not cross
4381 // bundle alignment boundaries, so keep it simple with one-byte NOPs.
4383 Target_i386_nacl::do_code_fill(section_size_type length
) const
4385 return std::string(length
, static_cast<char>(0x90));
4388 // The selector for i386-nacl object files.
4390 class Target_selector_i386_nacl
4391 : public Target_selector_nacl
<Target_selector_i386
, Target_i386_nacl
>
4394 Target_selector_i386_nacl()
4395 : Target_selector_nacl
<Target_selector_i386
,
4396 Target_i386_nacl
>("x86-32",
4402 Target_selector_i386_nacl target_selector_i386
;
4404 // IAMCU variant. It uses EM_IAMCU, not EM_386.
4406 class Target_iamcu
: public Target_i386
4410 : Target_i386(&iamcu_info
)
4414 // Information about this specific target which we pass to the
4415 // general Target structure.
4416 static const Target::Target_info iamcu_info
;
4419 const Target::Target_info
Target_iamcu::iamcu_info
=
4422 false, // is_big_endian
4423 elfcpp::EM_IAMCU
, // machine_code
4424 false, // has_make_symbol
4425 false, // has_resolve
4426 true, // has_code_fill
4427 true, // is_default_stack_executable
4428 true, // can_icf_inline_merge_sections
4430 "/usr/lib/libc.so.1", // dynamic_linker
4431 0x08048000, // default_text_segment_address
4432 0x1000, // abi_pagesize (overridable by -z max-page-size)
4433 0x1000, // common_pagesize (overridable by -z common-page-size)
4434 false, // isolate_execinstr
4436 elfcpp::SHN_UNDEF
, // small_common_shndx
4437 elfcpp::SHN_UNDEF
, // large_common_shndx
4438 0, // small_common_section_flags
4439 0, // large_common_section_flags
4440 NULL
, // attributes_section
4441 NULL
, // attributes_vendor
4442 "_start", // entry_symbol_name
4443 32, // hash_entry_size
4444 elfcpp::SHT_PROGBITS
, // unwind_section_type
4447 class Target_selector_iamcu
: public Target_selector
4450 Target_selector_iamcu()
4451 : Target_selector(elfcpp::EM_IAMCU
, 32, false, "elf32-iamcu",
4456 do_instantiate_target()
4457 { return new Target_iamcu(); }
4460 Target_selector_iamcu target_selector_iamcu
;
4462 } // End anonymous namespace.