1 // i386.cc -- i386 target support for gold.
3 // Copyright (C) 2006-2015 Free Software Foundation, Inc.
4 // Written by Ian Lance Taylor <iant@google.com>.
6 // This file is part of gold.
8 // This program is free software; you can redistribute it and/or modify
9 // it under the terms of the GNU General Public License as published by
10 // the Free Software Foundation; either version 3 of the License, or
11 // (at your option) any later version.
13 // This program is distributed in the hope that it will be useful,
14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 // GNU General Public License for more details.
18 // You should have received a copy of the GNU General Public License
19 // along with this program; if not, write to the Free Software
20 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
21 // MA 02110-1301, USA.
29 #include "parameters.h"
36 #include "copy-relocs.h"
38 #include "target-reloc.h"
39 #include "target-select.h"
50 // A class to handle the .got.plt section.
52 class Output_data_got_plt_i386
: public Output_section_data_build
55 Output_data_got_plt_i386(Layout
* layout
)
56 : Output_section_data_build(4),
61 // Write out the PLT data.
63 do_write(Output_file
*);
65 // Write to a map file.
67 do_print_to_mapfile(Mapfile
* mapfile
) const
68 { mapfile
->print_output_data(this, "** GOT PLT"); }
71 // A pointer to the Layout class, so that we can find the .dynamic
72 // section when we write out the GOT PLT section.
76 // A class to handle the PLT data.
77 // This is an abstract base class that handles most of the linker details
78 // but does not know the actual contents of PLT entries. The derived
79 // classes below fill in those details.
81 class Output_data_plt_i386
: public Output_section_data
84 typedef Output_data_reloc
<elfcpp::SHT_REL
, true, 32, false> Reloc_section
;
86 Output_data_plt_i386(Layout
*, uint64_t addralign
,
87 Output_data_got_plt_i386
*, Output_data_space
*);
89 // Add an entry to the PLT.
91 add_entry(Symbol_table
*, Layout
*, Symbol
* gsym
);
93 // Add an entry to the PLT for a local STT_GNU_IFUNC symbol.
95 add_local_ifunc_entry(Symbol_table
*, Layout
*,
96 Sized_relobj_file
<32, false>* relobj
,
97 unsigned int local_sym_index
);
99 // Return the .rel.plt section data.
102 { return this->rel_
; }
104 // Return where the TLS_DESC relocations should go.
106 rel_tls_desc(Layout
*);
108 // Return where the IRELATIVE relocations should go.
110 rel_irelative(Symbol_table
*, Layout
*);
112 // Return whether we created a section for IRELATIVE relocations.
114 has_irelative_section() const
115 { return this->irelative_rel_
!= NULL
; }
117 // Return the number of PLT entries.
120 { return this->count_
+ this->irelative_count_
; }
122 // Return the offset of the first non-reserved PLT entry.
124 first_plt_entry_offset()
125 { return this->get_plt_entry_size(); }
127 // Return the size of a PLT entry.
129 get_plt_entry_size() const
130 { return this->do_get_plt_entry_size(); }
132 // Return the PLT address to use for a global symbol.
134 address_for_global(const Symbol
*);
136 // Return the PLT address to use for a local symbol.
138 address_for_local(const Relobj
*, unsigned int symndx
);
140 // Add .eh_frame information for the PLT.
142 add_eh_frame(Layout
* layout
)
143 { this->do_add_eh_frame(layout
); }
146 // Fill the first PLT entry, given the pointer to the PLT section data
147 // and the runtime address of the GOT.
149 fill_first_plt_entry(unsigned char* pov
,
150 elfcpp::Elf_types
<32>::Elf_Addr got_address
)
151 { this->do_fill_first_plt_entry(pov
, got_address
); }
153 // Fill a normal PLT entry, given the pointer to the entry's data in the
154 // section, the runtime address of the GOT, the offset into the GOT of
155 // the corresponding slot, the offset into the relocation section of the
156 // corresponding reloc, and the offset of this entry within the whole
157 // PLT. Return the offset from this PLT entry's runtime address that
158 // should be used to compute the initial value of the GOT slot.
160 fill_plt_entry(unsigned char* pov
,
161 elfcpp::Elf_types
<32>::Elf_Addr got_address
,
162 unsigned int got_offset
,
163 unsigned int plt_offset
,
164 unsigned int plt_rel_offset
)
166 return this->do_fill_plt_entry(pov
, got_address
, got_offset
,
167 plt_offset
, plt_rel_offset
);
171 do_get_plt_entry_size() const = 0;
174 do_fill_first_plt_entry(unsigned char* pov
,
175 elfcpp::Elf_types
<32>::Elf_Addr got_address
) = 0;
178 do_fill_plt_entry(unsigned char* pov
,
179 elfcpp::Elf_types
<32>::Elf_Addr got_address
,
180 unsigned int got_offset
,
181 unsigned int plt_offset
,
182 unsigned int plt_rel_offset
) = 0;
185 do_add_eh_frame(Layout
*) = 0;
188 do_adjust_output_section(Output_section
* os
);
190 // Write to a map file.
192 do_print_to_mapfile(Mapfile
* mapfile
) const
193 { mapfile
->print_output_data(this, _("** PLT")); }
195 // The .eh_frame unwind information for the PLT.
196 // The CIE is common across variants of the PLT format.
197 static const int plt_eh_frame_cie_size
= 16;
198 static const unsigned char plt_eh_frame_cie
[plt_eh_frame_cie_size
];
201 // Set the final size.
203 set_final_data_size()
205 this->set_data_size((this->count_
+ this->irelative_count_
+ 1)
206 * this->get_plt_entry_size());
209 // Write out the PLT data.
211 do_write(Output_file
*);
213 // We keep a list of global STT_GNU_IFUNC symbols, each with its
214 // offset in the GOT.
218 unsigned int got_offset
;
221 // We keep a list of local STT_GNU_IFUNC symbols, each with its
222 // offset in the GOT.
225 Sized_relobj_file
<32, false>* object
;
226 unsigned int local_sym_index
;
227 unsigned int got_offset
;
230 // The reloc section.
232 // The TLS_DESC relocations, if necessary. These must follow the
233 // regular PLT relocs.
234 Reloc_section
* tls_desc_rel_
;
235 // The IRELATIVE relocations, if necessary. These must follow the
236 // regular relocatoins and the TLS_DESC relocations.
237 Reloc_section
* irelative_rel_
;
238 // The .got.plt section.
239 Output_data_got_plt_i386
* got_plt_
;
240 // The part of the .got.plt section used for IRELATIVE relocs.
241 Output_data_space
* got_irelative_
;
242 // The number of PLT entries.
244 // Number of PLT entries with R_386_IRELATIVE relocs. These follow
245 // the regular PLT entries.
246 unsigned int irelative_count_
;
247 // Global STT_GNU_IFUNC symbols.
248 std::vector
<Global_ifunc
> global_ifuncs_
;
249 // Local STT_GNU_IFUNC symbols.
250 std::vector
<Local_ifunc
> local_ifuncs_
;
253 // This is an abstract class for the standard PLT layout.
254 // The derived classes below handle the actual PLT contents
255 // for the executable (non-PIC) and shared-library (PIC) cases.
256 // The unwind information is uniform across those two, so it's here.
258 class Output_data_plt_i386_standard
: public Output_data_plt_i386
261 Output_data_plt_i386_standard(Layout
* layout
,
262 Output_data_got_plt_i386
* got_plt
,
263 Output_data_space
* got_irelative
)
264 : Output_data_plt_i386(layout
, plt_entry_size
, got_plt
, got_irelative
)
269 do_get_plt_entry_size() const
270 { return plt_entry_size
; }
273 do_add_eh_frame(Layout
* layout
)
275 layout
->add_eh_frame_for_plt(this, plt_eh_frame_cie
, plt_eh_frame_cie_size
,
276 plt_eh_frame_fde
, plt_eh_frame_fde_size
);
279 // The size of an entry in the PLT.
280 static const int plt_entry_size
= 16;
282 // The .eh_frame unwind information for the PLT.
283 static const int plt_eh_frame_fde_size
= 32;
284 static const unsigned char plt_eh_frame_fde
[plt_eh_frame_fde_size
];
287 // Actually fill the PLT contents for an executable (non-PIC).
289 class Output_data_plt_i386_exec
: public Output_data_plt_i386_standard
292 Output_data_plt_i386_exec(Layout
* layout
,
293 Output_data_got_plt_i386
* got_plt
,
294 Output_data_space
* got_irelative
)
295 : Output_data_plt_i386_standard(layout
, got_plt
, got_irelative
)
300 do_fill_first_plt_entry(unsigned char* pov
,
301 elfcpp::Elf_types
<32>::Elf_Addr got_address
);
304 do_fill_plt_entry(unsigned char* pov
,
305 elfcpp::Elf_types
<32>::Elf_Addr got_address
,
306 unsigned int got_offset
,
307 unsigned int plt_offset
,
308 unsigned int plt_rel_offset
);
311 // The first entry in the PLT for an executable.
312 static const unsigned char first_plt_entry
[plt_entry_size
];
314 // Other entries in the PLT for an executable.
315 static const unsigned char plt_entry
[plt_entry_size
];
318 // Actually fill the PLT contents for a shared library (PIC).
320 class Output_data_plt_i386_dyn
: public Output_data_plt_i386_standard
323 Output_data_plt_i386_dyn(Layout
* layout
,
324 Output_data_got_plt_i386
* got_plt
,
325 Output_data_space
* got_irelative
)
326 : Output_data_plt_i386_standard(layout
, got_plt
, got_irelative
)
331 do_fill_first_plt_entry(unsigned char* pov
, elfcpp::Elf_types
<32>::Elf_Addr
);
334 do_fill_plt_entry(unsigned char* pov
,
335 elfcpp::Elf_types
<32>::Elf_Addr
,
336 unsigned int got_offset
,
337 unsigned int plt_offset
,
338 unsigned int plt_rel_offset
);
341 // The first entry in the PLT for a shared object.
342 static const unsigned char first_plt_entry
[plt_entry_size
];
344 // Other entries in the PLT for a shared object.
345 static const unsigned char plt_entry
[plt_entry_size
];
348 // The i386 target class.
349 // TLS info comes from
350 // http://people.redhat.com/drepper/tls.pdf
351 // http://www.lsd.ic.unicamp.br/~oliva/writeups/TLS/RFC-TLSDESC-x86.txt
353 class Target_i386
: public Sized_target
<32, false>
356 typedef Output_data_reloc
<elfcpp::SHT_REL
, true, 32, false> Reloc_section
;
358 Target_i386(const Target::Target_info
* info
= &i386_info
)
359 : Sized_target
<32, false>(info
),
360 got_(NULL
), plt_(NULL
), got_plt_(NULL
), got_irelative_(NULL
),
361 got_tlsdesc_(NULL
), global_offset_table_(NULL
), rel_dyn_(NULL
),
362 rel_irelative_(NULL
), copy_relocs_(elfcpp::R_386_COPY
),
363 got_mod_index_offset_(-1U), tls_base_symbol_defined_(false)
366 // Process the relocations to determine unreferenced sections for
367 // garbage collection.
369 gc_process_relocs(Symbol_table
* symtab
,
371 Sized_relobj_file
<32, false>* object
,
372 unsigned int data_shndx
,
373 unsigned int sh_type
,
374 const unsigned char* prelocs
,
376 Output_section
* output_section
,
377 bool needs_special_offset_handling
,
378 size_t local_symbol_count
,
379 const unsigned char* plocal_symbols
);
381 // Scan the relocations to look for symbol adjustments.
383 scan_relocs(Symbol_table
* symtab
,
385 Sized_relobj_file
<32, false>* object
,
386 unsigned int data_shndx
,
387 unsigned int sh_type
,
388 const unsigned char* prelocs
,
390 Output_section
* output_section
,
391 bool needs_special_offset_handling
,
392 size_t local_symbol_count
,
393 const unsigned char* plocal_symbols
);
395 // Finalize the sections.
397 do_finalize_sections(Layout
*, const Input_objects
*, Symbol_table
*);
399 // Return the value to use for a dynamic which requires special
402 do_dynsym_value(const Symbol
*) const;
404 // Relocate a section.
406 relocate_section(const Relocate_info
<32, false>*,
407 unsigned int sh_type
,
408 const unsigned char* prelocs
,
410 Output_section
* output_section
,
411 bool needs_special_offset_handling
,
413 elfcpp::Elf_types
<32>::Elf_Addr view_address
,
414 section_size_type view_size
,
415 const Reloc_symbol_changes
*);
417 // Scan the relocs during a relocatable link.
419 scan_relocatable_relocs(Symbol_table
* symtab
,
421 Sized_relobj_file
<32, false>* object
,
422 unsigned int data_shndx
,
423 unsigned int sh_type
,
424 const unsigned char* prelocs
,
426 Output_section
* output_section
,
427 bool needs_special_offset_handling
,
428 size_t local_symbol_count
,
429 const unsigned char* plocal_symbols
,
430 Relocatable_relocs
*);
432 // Emit relocations for a section.
434 relocate_relocs(const Relocate_info
<32, false>*,
435 unsigned int sh_type
,
436 const unsigned char* prelocs
,
438 Output_section
* output_section
,
439 elfcpp::Elf_types
<32>::Elf_Off offset_in_output_section
,
440 const Relocatable_relocs
*,
442 elfcpp::Elf_types
<32>::Elf_Addr view_address
,
443 section_size_type view_size
,
444 unsigned char* reloc_view
,
445 section_size_type reloc_view_size
);
447 // Return a string used to fill a code section with nops.
449 do_code_fill(section_size_type length
) const;
451 // Return whether SYM is defined by the ABI.
453 do_is_defined_by_abi(const Symbol
* sym
) const
454 { return strcmp(sym
->name(), "___tls_get_addr") == 0; }
456 // Return whether a symbol name implies a local label. The UnixWare
457 // 2.1 cc generates temporary symbols that start with .X, so we
458 // recognize them here. FIXME: do other SVR4 compilers also use .X?.
459 // If so, we should move the .X recognition into
460 // Target::do_is_local_label_name.
462 do_is_local_label_name(const char* name
) const
464 if (name
[0] == '.' && name
[1] == 'X')
466 return Target::do_is_local_label_name(name
);
469 // Return the PLT address to use for a global symbol.
471 do_plt_address_for_global(const Symbol
* gsym
) const
472 { return this->plt_section()->address_for_global(gsym
); }
475 do_plt_address_for_local(const Relobj
* relobj
, unsigned int symndx
) const
476 { return this->plt_section()->address_for_local(relobj
, symndx
); }
478 // We can tell whether we take the address of a function.
480 do_can_check_for_function_pointers() const
483 // Return the base for a DW_EH_PE_datarel encoding.
485 do_ehframe_datarel_base() const;
487 // Return whether SYM is call to a non-split function.
489 do_is_call_to_non_split(const Symbol
* sym
, unsigned int) const;
491 // Adjust -fsplit-stack code which calls non-split-stack code.
493 do_calls_non_split(Relobj
* object
, unsigned int shndx
,
494 section_offset_type fnoffset
, section_size_type fnsize
,
495 unsigned char* view
, section_size_type view_size
,
496 std::string
* from
, std::string
* to
) const;
498 // Return the size of the GOT section.
502 gold_assert(this->got_
!= NULL
);
503 return this->got_
->data_size();
506 // Return the number of entries in the GOT.
508 got_entry_count() const
510 if (this->got_
== NULL
)
512 return this->got_size() / 4;
515 // Return the number of entries in the PLT.
517 plt_entry_count() const;
519 // Return the offset of the first non-reserved PLT entry.
521 first_plt_entry_offset() const;
523 // Return the size of each PLT entry.
525 plt_entry_size() const;
528 // Instantiate the plt_ member.
529 // This chooses the right PLT flavor for an executable or a shared object.
530 Output_data_plt_i386
*
531 make_data_plt(Layout
* layout
,
532 Output_data_got_plt_i386
* got_plt
,
533 Output_data_space
* got_irelative
,
535 { return this->do_make_data_plt(layout
, got_plt
, got_irelative
, dyn
); }
537 virtual Output_data_plt_i386
*
538 do_make_data_plt(Layout
* layout
,
539 Output_data_got_plt_i386
* got_plt
,
540 Output_data_space
* got_irelative
,
544 return new Output_data_plt_i386_dyn(layout
, got_plt
, got_irelative
);
546 return new Output_data_plt_i386_exec(layout
, got_plt
, got_irelative
);
550 // The class which scans relocations.
555 get_reference_flags(unsigned int r_type
);
558 local(Symbol_table
* symtab
, Layout
* layout
, Target_i386
* target
,
559 Sized_relobj_file
<32, false>* object
,
560 unsigned int data_shndx
,
561 Output_section
* output_section
,
562 const elfcpp::Rel
<32, false>& reloc
, unsigned int r_type
,
563 const elfcpp::Sym
<32, false>& lsym
,
567 global(Symbol_table
* symtab
, Layout
* layout
, Target_i386
* target
,
568 Sized_relobj_file
<32, false>* object
,
569 unsigned int data_shndx
,
570 Output_section
* output_section
,
571 const elfcpp::Rel
<32, false>& reloc
, unsigned int r_type
,
575 local_reloc_may_be_function_pointer(Symbol_table
* symtab
, Layout
* layout
,
577 Sized_relobj_file
<32, false>* object
,
578 unsigned int data_shndx
,
579 Output_section
* output_section
,
580 const elfcpp::Rel
<32, false>& reloc
,
582 const elfcpp::Sym
<32, false>& lsym
);
585 global_reloc_may_be_function_pointer(Symbol_table
* symtab
, Layout
* layout
,
587 Sized_relobj_file
<32, false>* object
,
588 unsigned int data_shndx
,
589 Output_section
* output_section
,
590 const elfcpp::Rel
<32, false>& reloc
,
595 possible_function_pointer_reloc(unsigned int r_type
);
598 reloc_needs_plt_for_ifunc(Sized_relobj_file
<32, false>*,
599 unsigned int r_type
);
602 unsupported_reloc_local(Sized_relobj_file
<32, false>*, unsigned int r_type
);
605 unsupported_reloc_global(Sized_relobj_file
<32, false>*, unsigned int r_type
,
609 // The class which implements relocation.
614 : skip_call_tls_get_addr_(false),
615 local_dynamic_type_(LOCAL_DYNAMIC_NONE
)
620 if (this->skip_call_tls_get_addr_
)
622 // FIXME: This needs to specify the location somehow.
623 gold_error(_("missing expected TLS relocation"));
627 // Return whether the static relocation needs to be applied.
629 should_apply_static_reloc(const Sized_symbol
<32>* gsym
,
632 Output_section
* output_section
);
634 // Do a relocation. Return false if the caller should not issue
635 // any warnings about this relocation.
637 relocate(const Relocate_info
<32, false>*, Target_i386
*, Output_section
*,
638 size_t relnum
, const elfcpp::Rel
<32, false>&,
639 unsigned int r_type
, const Sized_symbol
<32>*,
640 const Symbol_value
<32>*,
641 unsigned char*, elfcpp::Elf_types
<32>::Elf_Addr
,
645 // Do a TLS relocation.
647 relocate_tls(const Relocate_info
<32, false>*, Target_i386
* target
,
648 size_t relnum
, const elfcpp::Rel
<32, false>&,
649 unsigned int r_type
, const Sized_symbol
<32>*,
650 const Symbol_value
<32>*,
651 unsigned char*, elfcpp::Elf_types
<32>::Elf_Addr
,
654 // Do a TLS General-Dynamic to Initial-Exec transition.
656 tls_gd_to_ie(const Relocate_info
<32, false>*, size_t relnum
,
657 Output_segment
* tls_segment
,
658 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
659 elfcpp::Elf_types
<32>::Elf_Addr value
,
661 section_size_type view_size
);
663 // Do a TLS General-Dynamic to Local-Exec transition.
665 tls_gd_to_le(const Relocate_info
<32, false>*, size_t relnum
,
666 Output_segment
* tls_segment
,
667 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
668 elfcpp::Elf_types
<32>::Elf_Addr value
,
670 section_size_type view_size
);
672 // Do a TLS_GOTDESC or TLS_DESC_CALL General-Dynamic to Initial-Exec
675 tls_desc_gd_to_ie(const Relocate_info
<32, false>*, size_t relnum
,
676 Output_segment
* tls_segment
,
677 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
678 elfcpp::Elf_types
<32>::Elf_Addr value
,
680 section_size_type view_size
);
682 // Do a TLS_GOTDESC or TLS_DESC_CALL General-Dynamic to Local-Exec
685 tls_desc_gd_to_le(const Relocate_info
<32, false>*, size_t relnum
,
686 Output_segment
* tls_segment
,
687 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
688 elfcpp::Elf_types
<32>::Elf_Addr value
,
690 section_size_type view_size
);
692 // Do a TLS Local-Dynamic to Local-Exec transition.
694 tls_ld_to_le(const Relocate_info
<32, false>*, size_t relnum
,
695 Output_segment
* tls_segment
,
696 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
697 elfcpp::Elf_types
<32>::Elf_Addr value
,
699 section_size_type view_size
);
701 // Do a TLS Initial-Exec to Local-Exec transition.
703 tls_ie_to_le(const Relocate_info
<32, false>*, size_t relnum
,
704 Output_segment
* tls_segment
,
705 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
706 elfcpp::Elf_types
<32>::Elf_Addr value
,
708 section_size_type view_size
);
710 // We need to keep track of which type of local dynamic relocation
711 // we have seen, so that we can optimize R_386_TLS_LDO_32 correctly.
712 enum Local_dynamic_type
719 // This is set if we should skip the next reloc, which should be a
720 // PLT32 reloc against ___tls_get_addr.
721 bool skip_call_tls_get_addr_
;
722 // The type of local dynamic relocation we have seen in the section
723 // being relocated, if any.
724 Local_dynamic_type local_dynamic_type_
;
727 // A class which returns the size required for a relocation type,
728 // used while scanning relocs during a relocatable link.
729 class Relocatable_size_for_reloc
733 get_size_for_reloc(unsigned int, Relobj
*);
736 // Adjust TLS relocation type based on the options and whether this
737 // is a local symbol.
738 static tls::Tls_optimization
739 optimize_tls_reloc(bool is_final
, int r_type
);
741 // Check if relocation against this symbol is a candidate for
743 // mov foo@GOT(%reg), %reg
745 // lea foo@GOTOFF(%reg), %reg.
747 can_convert_mov_to_lea(const Symbol
* gsym
)
749 gold_assert(gsym
!= NULL
);
750 return (gsym
->type() != elfcpp::STT_GNU_IFUNC
751 && !gsym
->is_undefined ()
752 && !gsym
->is_from_dynobj()
753 && !gsym
->is_preemptible()
754 && (!parameters
->options().shared()
755 || (gsym
->visibility() != elfcpp::STV_DEFAULT
756 && gsym
->visibility() != elfcpp::STV_PROTECTED
)
757 || parameters
->options().Bsymbolic())
758 && strcmp(gsym
->name(), "_DYNAMIC") != 0);
761 // Get the GOT section, creating it if necessary.
762 Output_data_got
<32, false>*
763 got_section(Symbol_table
*, Layout
*);
765 // Get the GOT PLT section.
766 Output_data_got_plt_i386
*
767 got_plt_section() const
769 gold_assert(this->got_plt_
!= NULL
);
770 return this->got_plt_
;
773 // Get the GOT section for TLSDESC entries.
774 Output_data_got
<32, false>*
775 got_tlsdesc_section() const
777 gold_assert(this->got_tlsdesc_
!= NULL
);
778 return this->got_tlsdesc_
;
781 // Create the PLT section.
783 make_plt_section(Symbol_table
* symtab
, Layout
* layout
);
785 // Create a PLT entry for a global symbol.
787 make_plt_entry(Symbol_table
*, Layout
*, Symbol
*);
789 // Create a PLT entry for a local STT_GNU_IFUNC symbol.
791 make_local_ifunc_plt_entry(Symbol_table
*, Layout
*,
792 Sized_relobj_file
<32, false>* relobj
,
793 unsigned int local_sym_index
);
795 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
797 define_tls_base_symbol(Symbol_table
*, Layout
*);
799 // Create a GOT entry for the TLS module index.
801 got_mod_index_entry(Symbol_table
* symtab
, Layout
* layout
,
802 Sized_relobj_file
<32, false>* object
);
804 // Get the PLT section.
805 Output_data_plt_i386
*
808 gold_assert(this->plt_
!= NULL
);
812 // Get the dynamic reloc section, creating it if necessary.
814 rel_dyn_section(Layout
*);
816 // Get the section to use for TLS_DESC relocations.
818 rel_tls_desc_section(Layout
*) const;
820 // Get the section to use for IRELATIVE relocations.
822 rel_irelative_section(Layout
*);
824 // Add a potential copy relocation.
826 copy_reloc(Symbol_table
* symtab
, Layout
* layout
,
827 Sized_relobj_file
<32, false>* object
,
828 unsigned int shndx
, Output_section
* output_section
,
829 Symbol
* sym
, const elfcpp::Rel
<32, false>& reloc
)
831 this->copy_relocs_
.copy_reloc(symtab
, layout
,
832 symtab
->get_sized_symbol
<32>(sym
),
833 object
, shndx
, output_section
, reloc
,
834 this->rel_dyn_section(layout
));
837 // Information about this specific target which we pass to the
838 // general Target structure.
839 static const Target::Target_info i386_info
;
841 // The types of GOT entries needed for this platform.
842 // These values are exposed to the ABI in an incremental link.
843 // Do not renumber existing values without changing the version
844 // number of the .gnu_incremental_inputs section.
847 GOT_TYPE_STANDARD
= 0, // GOT entry for a regular symbol
848 GOT_TYPE_TLS_NOFFSET
= 1, // GOT entry for negative TLS offset
849 GOT_TYPE_TLS_OFFSET
= 2, // GOT entry for positive TLS offset
850 GOT_TYPE_TLS_PAIR
= 3, // GOT entry for TLS module/offset pair
851 GOT_TYPE_TLS_DESC
= 4 // GOT entry for TLS_DESC pair
855 Output_data_got
<32, false>* got_
;
857 Output_data_plt_i386
* plt_
;
858 // The GOT PLT section.
859 Output_data_got_plt_i386
* got_plt_
;
860 // The GOT section for IRELATIVE relocations.
861 Output_data_space
* got_irelative_
;
862 // The GOT section for TLSDESC relocations.
863 Output_data_got
<32, false>* got_tlsdesc_
;
864 // The _GLOBAL_OFFSET_TABLE_ symbol.
865 Symbol
* global_offset_table_
;
866 // The dynamic reloc section.
867 Reloc_section
* rel_dyn_
;
868 // The section to use for IRELATIVE relocs.
869 Reloc_section
* rel_irelative_
;
870 // Relocs saved to avoid a COPY reloc.
871 Copy_relocs
<elfcpp::SHT_REL
, 32, false> copy_relocs_
;
872 // Offset of the GOT entry for the TLS module index.
873 unsigned int got_mod_index_offset_
;
874 // True if the _TLS_MODULE_BASE_ symbol has been defined.
875 bool tls_base_symbol_defined_
;
878 const Target::Target_info
Target_i386::i386_info
=
881 false, // is_big_endian
882 elfcpp::EM_386
, // machine_code
883 false, // has_make_symbol
884 false, // has_resolve
885 true, // has_code_fill
886 true, // is_default_stack_executable
887 true, // can_icf_inline_merge_sections
889 "/usr/lib/libc.so.1", // dynamic_linker
890 0x08048000, // default_text_segment_address
891 0x1000, // abi_pagesize (overridable by -z max-page-size)
892 0x1000, // common_pagesize (overridable by -z common-page-size)
893 false, // isolate_execinstr
895 elfcpp::SHN_UNDEF
, // small_common_shndx
896 elfcpp::SHN_UNDEF
, // large_common_shndx
897 0, // small_common_section_flags
898 0, // large_common_section_flags
899 NULL
, // attributes_section
900 NULL
, // attributes_vendor
901 "_start" // entry_symbol_name
904 // Get the GOT section, creating it if necessary.
906 Output_data_got
<32, false>*
907 Target_i386::got_section(Symbol_table
* symtab
, Layout
* layout
)
909 if (this->got_
== NULL
)
911 gold_assert(symtab
!= NULL
&& layout
!= NULL
);
913 this->got_
= new Output_data_got
<32, false>();
915 // When using -z now, we can treat .got.plt as a relro section.
916 // Without -z now, it is modified after program startup by lazy
918 bool is_got_plt_relro
= parameters
->options().now();
919 Output_section_order got_order
= (is_got_plt_relro
922 Output_section_order got_plt_order
= (is_got_plt_relro
924 : ORDER_NON_RELRO_FIRST
);
926 layout
->add_output_section_data(".got", elfcpp::SHT_PROGBITS
,
928 | elfcpp::SHF_WRITE
),
929 this->got_
, got_order
, true);
931 this->got_plt_
= new Output_data_got_plt_i386(layout
);
932 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
934 | elfcpp::SHF_WRITE
),
935 this->got_plt_
, got_plt_order
,
938 // The first three entries are reserved.
939 this->got_plt_
->set_current_data_size(3 * 4);
941 if (!is_got_plt_relro
)
943 // Those bytes can go into the relro segment.
944 layout
->increase_relro(3 * 4);
947 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
948 this->global_offset_table_
=
949 symtab
->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL
,
950 Symbol_table::PREDEFINED
,
952 0, 0, elfcpp::STT_OBJECT
,
954 elfcpp::STV_HIDDEN
, 0,
957 // If there are any IRELATIVE relocations, they get GOT entries
958 // in .got.plt after the jump slot relocations.
959 this->got_irelative_
= new Output_data_space(4, "** GOT IRELATIVE PLT");
960 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
962 | elfcpp::SHF_WRITE
),
963 this->got_irelative_
,
964 got_plt_order
, is_got_plt_relro
);
966 // If there are any TLSDESC relocations, they get GOT entries in
967 // .got.plt after the jump slot entries.
968 this->got_tlsdesc_
= new Output_data_got
<32, false>();
969 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
971 | elfcpp::SHF_WRITE
),
973 got_plt_order
, is_got_plt_relro
);
979 // Get the dynamic reloc section, creating it if necessary.
981 Target_i386::Reloc_section
*
982 Target_i386::rel_dyn_section(Layout
* layout
)
984 if (this->rel_dyn_
== NULL
)
986 gold_assert(layout
!= NULL
);
987 this->rel_dyn_
= new Reloc_section(parameters
->options().combreloc());
988 layout
->add_output_section_data(".rel.dyn", elfcpp::SHT_REL
,
989 elfcpp::SHF_ALLOC
, this->rel_dyn_
,
990 ORDER_DYNAMIC_RELOCS
, false);
992 return this->rel_dyn_
;
995 // Get the section to use for IRELATIVE relocs, creating it if
996 // necessary. These go in .rel.dyn, but only after all other dynamic
997 // relocations. They need to follow the other dynamic relocations so
998 // that they can refer to global variables initialized by those
1001 Target_i386::Reloc_section
*
1002 Target_i386::rel_irelative_section(Layout
* layout
)
1004 if (this->rel_irelative_
== NULL
)
1006 // Make sure we have already create the dynamic reloc section.
1007 this->rel_dyn_section(layout
);
1008 this->rel_irelative_
= new Reloc_section(false);
1009 layout
->add_output_section_data(".rel.dyn", elfcpp::SHT_REL
,
1010 elfcpp::SHF_ALLOC
, this->rel_irelative_
,
1011 ORDER_DYNAMIC_RELOCS
, false);
1012 gold_assert(this->rel_dyn_
->output_section()
1013 == this->rel_irelative_
->output_section());
1015 return this->rel_irelative_
;
1018 // Write the first three reserved words of the .got.plt section.
1019 // The remainder of the section is written while writing the PLT
1020 // in Output_data_plt_i386::do_write.
1023 Output_data_got_plt_i386::do_write(Output_file
* of
)
1025 // The first entry in the GOT is the address of the .dynamic section
1026 // aka the PT_DYNAMIC segment. The next two entries are reserved.
1027 // We saved space for them when we created the section in
1028 // Target_i386::got_section.
1029 const off_t got_file_offset
= this->offset();
1030 gold_assert(this->data_size() >= 12);
1031 unsigned char* const got_view
= of
->get_output_view(got_file_offset
, 12);
1032 Output_section
* dynamic
= this->layout_
->dynamic_section();
1033 uint32_t dynamic_addr
= dynamic
== NULL
? 0 : dynamic
->address();
1034 elfcpp::Swap
<32, false>::writeval(got_view
, dynamic_addr
);
1035 memset(got_view
+ 4, 0, 8);
1036 of
->write_output_view(got_file_offset
, 12, got_view
);
1039 // Create the PLT section. The ordinary .got section is an argument,
1040 // since we need to refer to the start. We also create our own .got
1041 // section just for PLT entries.
1043 Output_data_plt_i386::Output_data_plt_i386(Layout
* layout
,
1045 Output_data_got_plt_i386
* got_plt
,
1046 Output_data_space
* got_irelative
)
1047 : Output_section_data(addralign
),
1048 tls_desc_rel_(NULL
), irelative_rel_(NULL
), got_plt_(got_plt
),
1049 got_irelative_(got_irelative
), count_(0), irelative_count_(0),
1050 global_ifuncs_(), local_ifuncs_()
1052 this->rel_
= new Reloc_section(false);
1053 layout
->add_output_section_data(".rel.plt", elfcpp::SHT_REL
,
1054 elfcpp::SHF_ALLOC
, this->rel_
,
1055 ORDER_DYNAMIC_PLT_RELOCS
, false);
1059 Output_data_plt_i386::do_adjust_output_section(Output_section
* os
)
1061 // UnixWare sets the entsize of .plt to 4, and so does the old GNU
1062 // linker, and so do we.
1066 // Add an entry to the PLT.
1069 Output_data_plt_i386::add_entry(Symbol_table
* symtab
, Layout
* layout
,
1072 gold_assert(!gsym
->has_plt_offset());
1074 // Every PLT entry needs a reloc.
1075 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
1076 && gsym
->can_use_relative_reloc(false))
1078 gsym
->set_plt_offset(this->irelative_count_
* this->get_plt_entry_size());
1079 ++this->irelative_count_
;
1080 section_offset_type got_offset
=
1081 this->got_irelative_
->current_data_size();
1082 this->got_irelative_
->set_current_data_size(got_offset
+ 4);
1083 Reloc_section
* rel
= this->rel_irelative(symtab
, layout
);
1084 rel
->add_symbolless_global_addend(gsym
, elfcpp::R_386_IRELATIVE
,
1085 this->got_irelative_
, got_offset
);
1086 struct Global_ifunc gi
;
1088 gi
.got_offset
= got_offset
;
1089 this->global_ifuncs_
.push_back(gi
);
1093 // When setting the PLT offset we skip the initial reserved PLT
1095 gsym
->set_plt_offset((this->count_
+ 1) * this->get_plt_entry_size());
1099 section_offset_type got_offset
= this->got_plt_
->current_data_size();
1101 // Every PLT entry needs a GOT entry which points back to the
1102 // PLT entry (this will be changed by the dynamic linker,
1103 // normally lazily when the function is called).
1104 this->got_plt_
->set_current_data_size(got_offset
+ 4);
1106 gsym
->set_needs_dynsym_entry();
1107 this->rel_
->add_global(gsym
, elfcpp::R_386_JUMP_SLOT
, this->got_plt_
,
1111 // Note that we don't need to save the symbol. The contents of the
1112 // PLT are independent of which symbols are used. The symbols only
1113 // appear in the relocations.
1116 // Add an entry to the PLT for a local STT_GNU_IFUNC symbol. Return
1120 Output_data_plt_i386::add_local_ifunc_entry(
1121 Symbol_table
* symtab
,
1123 Sized_relobj_file
<32, false>* relobj
,
1124 unsigned int local_sym_index
)
1126 unsigned int plt_offset
= this->irelative_count_
* this->get_plt_entry_size();
1127 ++this->irelative_count_
;
1129 section_offset_type got_offset
= this->got_irelative_
->current_data_size();
1131 // Every PLT entry needs a GOT entry which points back to the PLT
1133 this->got_irelative_
->set_current_data_size(got_offset
+ 4);
1135 // Every PLT entry needs a reloc.
1136 Reloc_section
* rel
= this->rel_irelative(symtab
, layout
);
1137 rel
->add_symbolless_local_addend(relobj
, local_sym_index
,
1138 elfcpp::R_386_IRELATIVE
,
1139 this->got_irelative_
, got_offset
);
1141 struct Local_ifunc li
;
1143 li
.local_sym_index
= local_sym_index
;
1144 li
.got_offset
= got_offset
;
1145 this->local_ifuncs_
.push_back(li
);
1150 // Return where the TLS_DESC relocations should go, creating it if
1151 // necessary. These follow the JUMP_SLOT relocations.
1153 Output_data_plt_i386::Reloc_section
*
1154 Output_data_plt_i386::rel_tls_desc(Layout
* layout
)
1156 if (this->tls_desc_rel_
== NULL
)
1158 this->tls_desc_rel_
= new Reloc_section(false);
1159 layout
->add_output_section_data(".rel.plt", elfcpp::SHT_REL
,
1160 elfcpp::SHF_ALLOC
, this->tls_desc_rel_
,
1161 ORDER_DYNAMIC_PLT_RELOCS
, false);
1162 gold_assert(this->tls_desc_rel_
->output_section()
1163 == this->rel_
->output_section());
1165 return this->tls_desc_rel_
;
1168 // Return where the IRELATIVE relocations should go in the PLT. These
1169 // follow the JUMP_SLOT and TLS_DESC relocations.
1171 Output_data_plt_i386::Reloc_section
*
1172 Output_data_plt_i386::rel_irelative(Symbol_table
* symtab
, Layout
* layout
)
1174 if (this->irelative_rel_
== NULL
)
1176 // Make sure we have a place for the TLS_DESC relocations, in
1177 // case we see any later on.
1178 this->rel_tls_desc(layout
);
1179 this->irelative_rel_
= new Reloc_section(false);
1180 layout
->add_output_section_data(".rel.plt", elfcpp::SHT_REL
,
1181 elfcpp::SHF_ALLOC
, this->irelative_rel_
,
1182 ORDER_DYNAMIC_PLT_RELOCS
, false);
1183 gold_assert(this->irelative_rel_
->output_section()
1184 == this->rel_
->output_section());
1186 if (parameters
->doing_static_link())
1188 // A statically linked executable will only have a .rel.plt
1189 // section to hold R_386_IRELATIVE relocs for STT_GNU_IFUNC
1190 // symbols. The library will use these symbols to locate
1191 // the IRELATIVE relocs at program startup time.
1192 symtab
->define_in_output_data("__rel_iplt_start", NULL
,
1193 Symbol_table::PREDEFINED
,
1194 this->irelative_rel_
, 0, 0,
1195 elfcpp::STT_NOTYPE
, elfcpp::STB_GLOBAL
,
1196 elfcpp::STV_HIDDEN
, 0, false, true);
1197 symtab
->define_in_output_data("__rel_iplt_end", NULL
,
1198 Symbol_table::PREDEFINED
,
1199 this->irelative_rel_
, 0, 0,
1200 elfcpp::STT_NOTYPE
, elfcpp::STB_GLOBAL
,
1201 elfcpp::STV_HIDDEN
, 0, true, true);
1204 return this->irelative_rel_
;
1207 // Return the PLT address to use for a global symbol.
1210 Output_data_plt_i386::address_for_global(const Symbol
* gsym
)
1212 uint64_t offset
= 0;
1213 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
1214 && gsym
->can_use_relative_reloc(false))
1215 offset
= (this->count_
+ 1) * this->get_plt_entry_size();
1216 return this->address() + offset
+ gsym
->plt_offset();
1219 // Return the PLT address to use for a local symbol. These are always
1220 // IRELATIVE relocs.
1223 Output_data_plt_i386::address_for_local(const Relobj
* object
,
1226 return (this->address()
1227 + (this->count_
+ 1) * this->get_plt_entry_size()
1228 + object
->local_plt_offset(r_sym
));
1231 // The first entry in the PLT for an executable.
1233 const unsigned char Output_data_plt_i386_exec::first_plt_entry
[plt_entry_size
] =
1235 0xff, 0x35, // pushl contents of memory address
1236 0, 0, 0, 0, // replaced with address of .got + 4
1237 0xff, 0x25, // jmp indirect
1238 0, 0, 0, 0, // replaced with address of .got + 8
1239 0, 0, 0, 0 // unused
1243 Output_data_plt_i386_exec::do_fill_first_plt_entry(
1245 elfcpp::Elf_types
<32>::Elf_Addr got_address
)
1247 memcpy(pov
, first_plt_entry
, plt_entry_size
);
1248 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2, got_address
+ 4);
1249 elfcpp::Swap
<32, false>::writeval(pov
+ 8, got_address
+ 8);
1252 // The first entry in the PLT for a shared object.
1254 const unsigned char Output_data_plt_i386_dyn::first_plt_entry
[plt_entry_size
] =
1256 0xff, 0xb3, 4, 0, 0, 0, // pushl 4(%ebx)
1257 0xff, 0xa3, 8, 0, 0, 0, // jmp *8(%ebx)
1258 0, 0, 0, 0 // unused
1262 Output_data_plt_i386_dyn::do_fill_first_plt_entry(
1264 elfcpp::Elf_types
<32>::Elf_Addr
)
1266 memcpy(pov
, first_plt_entry
, plt_entry_size
);
1269 // Subsequent entries in the PLT for an executable.
1271 const unsigned char Output_data_plt_i386_exec::plt_entry
[plt_entry_size
] =
1273 0xff, 0x25, // jmp indirect
1274 0, 0, 0, 0, // replaced with address of symbol in .got
1275 0x68, // pushl immediate
1276 0, 0, 0, 0, // replaced with offset into relocation table
1277 0xe9, // jmp relative
1278 0, 0, 0, 0 // replaced with offset to start of .plt
1282 Output_data_plt_i386_exec::do_fill_plt_entry(
1284 elfcpp::Elf_types
<32>::Elf_Addr got_address
,
1285 unsigned int got_offset
,
1286 unsigned int plt_offset
,
1287 unsigned int plt_rel_offset
)
1289 memcpy(pov
, plt_entry
, plt_entry_size
);
1290 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
1291 got_address
+ got_offset
);
1292 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 7, plt_rel_offset
);
1293 elfcpp::Swap
<32, false>::writeval(pov
+ 12, - (plt_offset
+ 12 + 4));
1297 // Subsequent entries in the PLT for a shared object.
1299 const unsigned char Output_data_plt_i386_dyn::plt_entry
[plt_entry_size
] =
1301 0xff, 0xa3, // jmp *offset(%ebx)
1302 0, 0, 0, 0, // replaced with offset of symbol in .got
1303 0x68, // pushl immediate
1304 0, 0, 0, 0, // replaced with offset into relocation table
1305 0xe9, // jmp relative
1306 0, 0, 0, 0 // replaced with offset to start of .plt
1310 Output_data_plt_i386_dyn::do_fill_plt_entry(unsigned char* pov
,
1311 elfcpp::Elf_types
<32>::Elf_Addr
,
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, got_offset
);
1318 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 7, plt_rel_offset
);
1319 elfcpp::Swap
<32, false>::writeval(pov
+ 12, - (plt_offset
+ 12 + 4));
1323 // The .eh_frame unwind information for the PLT.
1326 Output_data_plt_i386::plt_eh_frame_cie
[plt_eh_frame_cie_size
] =
1329 'z', // Augmentation: augmentation size included.
1330 'R', // Augmentation: FDE encoding included.
1331 '\0', // End of augmentation string.
1332 1, // Code alignment factor.
1333 0x7c, // Data alignment factor.
1334 8, // Return address column.
1335 1, // Augmentation size.
1336 (elfcpp::DW_EH_PE_pcrel
// FDE encoding.
1337 | elfcpp::DW_EH_PE_sdata4
),
1338 elfcpp::DW_CFA_def_cfa
, 4, 4, // DW_CFA_def_cfa: r4 (esp) ofs 4.
1339 elfcpp::DW_CFA_offset
+ 8, 1, // DW_CFA_offset: r8 (eip) at cfa-4.
1340 elfcpp::DW_CFA_nop
, // Align to 16 bytes.
1345 Output_data_plt_i386_standard::plt_eh_frame_fde
[plt_eh_frame_fde_size
] =
1347 0, 0, 0, 0, // Replaced with offset to .plt.
1348 0, 0, 0, 0, // Replaced with size of .plt.
1349 0, // Augmentation size.
1350 elfcpp::DW_CFA_def_cfa_offset
, 8, // DW_CFA_def_cfa_offset: 8.
1351 elfcpp::DW_CFA_advance_loc
+ 6, // Advance 6 to __PLT__ + 6.
1352 elfcpp::DW_CFA_def_cfa_offset
, 12, // DW_CFA_def_cfa_offset: 12.
1353 elfcpp::DW_CFA_advance_loc
+ 10, // Advance 10 to __PLT__ + 16.
1354 elfcpp::DW_CFA_def_cfa_expression
, // DW_CFA_def_cfa_expression.
1355 11, // Block length.
1356 elfcpp::DW_OP_breg4
, 4, // Push %esp + 4.
1357 elfcpp::DW_OP_breg8
, 0, // Push %eip.
1358 elfcpp::DW_OP_lit15
, // Push 0xf.
1359 elfcpp::DW_OP_and
, // & (%eip & 0xf).
1360 elfcpp::DW_OP_lit11
, // Push 0xb.
1361 elfcpp::DW_OP_ge
, // >= ((%eip & 0xf) >= 0xb)
1362 elfcpp::DW_OP_lit2
, // Push 2.
1363 elfcpp::DW_OP_shl
, // << (((%eip & 0xf) >= 0xb) << 2)
1364 elfcpp::DW_OP_plus
, // + ((((%eip&0xf)>=0xb)<<2)+%esp+4
1365 elfcpp::DW_CFA_nop
, // Align to 32 bytes.
1371 // Write out the PLT. This uses the hand-coded instructions above,
1372 // and adjusts them as needed. This is all specified by the i386 ELF
1373 // Processor Supplement.
1376 Output_data_plt_i386::do_write(Output_file
* of
)
1378 const off_t offset
= this->offset();
1379 const section_size_type oview_size
=
1380 convert_to_section_size_type(this->data_size());
1381 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
1383 const off_t got_file_offset
= this->got_plt_
->offset();
1384 gold_assert(parameters
->incremental_update()
1385 || (got_file_offset
+ this->got_plt_
->data_size()
1386 == this->got_irelative_
->offset()));
1387 const section_size_type got_size
=
1388 convert_to_section_size_type(this->got_plt_
->data_size()
1389 + this->got_irelative_
->data_size());
1391 unsigned char* const got_view
= of
->get_output_view(got_file_offset
,
1394 unsigned char* pov
= oview
;
1396 elfcpp::Elf_types
<32>::Elf_Addr plt_address
= this->address();
1397 elfcpp::Elf_types
<32>::Elf_Addr got_address
= this->got_plt_
->address();
1399 this->fill_first_plt_entry(pov
, got_address
);
1400 pov
+= this->get_plt_entry_size();
1402 // The first three entries in the GOT are reserved, and are written
1403 // by Output_data_got_plt_i386::do_write.
1404 unsigned char* got_pov
= got_view
+ 12;
1406 const int rel_size
= elfcpp::Elf_sizes
<32>::rel_size
;
1408 unsigned int plt_offset
= this->get_plt_entry_size();
1409 unsigned int plt_rel_offset
= 0;
1410 unsigned int got_offset
= 12;
1411 const unsigned int count
= this->count_
+ this->irelative_count_
;
1412 for (unsigned int i
= 0;
1415 pov
+= this->get_plt_entry_size(),
1417 plt_offset
+= this->get_plt_entry_size(),
1418 plt_rel_offset
+= rel_size
,
1421 // Set and adjust the PLT entry itself.
1422 unsigned int lazy_offset
= this->fill_plt_entry(pov
,
1428 // Set the entry in the GOT.
1429 elfcpp::Swap
<32, false>::writeval(got_pov
,
1430 plt_address
+ plt_offset
+ lazy_offset
);
1433 // If any STT_GNU_IFUNC symbols have PLT entries, we need to change
1434 // the GOT to point to the actual symbol value, rather than point to
1435 // the PLT entry. That will let the dynamic linker call the right
1436 // function when resolving IRELATIVE relocations.
1437 unsigned char* got_irelative_view
= got_view
+ this->got_plt_
->data_size();
1438 for (std::vector
<Global_ifunc
>::const_iterator p
=
1439 this->global_ifuncs_
.begin();
1440 p
!= this->global_ifuncs_
.end();
1443 const Sized_symbol
<32>* ssym
=
1444 static_cast<const Sized_symbol
<32>*>(p
->sym
);
1445 elfcpp::Swap
<32, false>::writeval(got_irelative_view
+ p
->got_offset
,
1449 for (std::vector
<Local_ifunc
>::const_iterator p
=
1450 this->local_ifuncs_
.begin();
1451 p
!= this->local_ifuncs_
.end();
1454 const Symbol_value
<32>* psymval
=
1455 p
->object
->local_symbol(p
->local_sym_index
);
1456 elfcpp::Swap
<32, false>::writeval(got_irelative_view
+ p
->got_offset
,
1457 psymval
->value(p
->object
, 0));
1460 gold_assert(static_cast<section_size_type
>(pov
- oview
) == oview_size
);
1461 gold_assert(static_cast<section_size_type
>(got_pov
- got_view
) == got_size
);
1463 of
->write_output_view(offset
, oview_size
, oview
);
1464 of
->write_output_view(got_file_offset
, got_size
, got_view
);
1467 // Create the PLT section.
1470 Target_i386::make_plt_section(Symbol_table
* symtab
, Layout
* layout
)
1472 if (this->plt_
== NULL
)
1474 // Create the GOT sections first.
1475 this->got_section(symtab
, layout
);
1477 const bool dyn
= parameters
->options().output_is_position_independent();
1478 this->plt_
= this->make_data_plt(layout
,
1480 this->got_irelative_
,
1483 // Add unwind information if requested.
1484 if (parameters
->options().ld_generated_unwind_info())
1485 this->plt_
->add_eh_frame(layout
);
1487 layout
->add_output_section_data(".plt", elfcpp::SHT_PROGBITS
,
1489 | elfcpp::SHF_EXECINSTR
),
1490 this->plt_
, ORDER_PLT
, false);
1492 // Make the sh_info field of .rel.plt point to .plt.
1493 Output_section
* rel_plt_os
= this->plt_
->rel_plt()->output_section();
1494 rel_plt_os
->set_info_section(this->plt_
->output_section());
1498 // Create a PLT entry for a global symbol.
1501 Target_i386::make_plt_entry(Symbol_table
* symtab
, Layout
* layout
, Symbol
* gsym
)
1503 if (gsym
->has_plt_offset())
1505 if (this->plt_
== NULL
)
1506 this->make_plt_section(symtab
, layout
);
1507 this->plt_
->add_entry(symtab
, layout
, gsym
);
1510 // Make a PLT entry for a local STT_GNU_IFUNC symbol.
1513 Target_i386::make_local_ifunc_plt_entry(Symbol_table
* symtab
, Layout
* layout
,
1514 Sized_relobj_file
<32, false>* relobj
,
1515 unsigned int local_sym_index
)
1517 if (relobj
->local_has_plt_offset(local_sym_index
))
1519 if (this->plt_
== NULL
)
1520 this->make_plt_section(symtab
, layout
);
1521 unsigned int plt_offset
= this->plt_
->add_local_ifunc_entry(symtab
, layout
,
1524 relobj
->set_local_plt_offset(local_sym_index
, plt_offset
);
1527 // Return the number of entries in the PLT.
1530 Target_i386::plt_entry_count() const
1532 if (this->plt_
== NULL
)
1534 return this->plt_
->entry_count();
1537 // Return the offset of the first non-reserved PLT entry.
1540 Target_i386::first_plt_entry_offset() const
1542 return this->plt_
->first_plt_entry_offset();
1545 // Return the size of each PLT entry.
1548 Target_i386::plt_entry_size() const
1550 return this->plt_
->get_plt_entry_size();
1553 // Get the section to use for TLS_DESC relocations.
1555 Target_i386::Reloc_section
*
1556 Target_i386::rel_tls_desc_section(Layout
* layout
) const
1558 return this->plt_section()->rel_tls_desc(layout
);
1561 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
1564 Target_i386::define_tls_base_symbol(Symbol_table
* symtab
, Layout
* layout
)
1566 if (this->tls_base_symbol_defined_
)
1569 Output_segment
* tls_segment
= layout
->tls_segment();
1570 if (tls_segment
!= NULL
)
1572 bool is_exec
= parameters
->options().output_is_executable();
1573 symtab
->define_in_output_segment("_TLS_MODULE_BASE_", NULL
,
1574 Symbol_table::PREDEFINED
,
1578 elfcpp::STV_HIDDEN
, 0,
1580 ? Symbol::SEGMENT_END
1581 : Symbol::SEGMENT_START
),
1584 this->tls_base_symbol_defined_
= true;
1587 // Create a GOT entry for the TLS module index.
1590 Target_i386::got_mod_index_entry(Symbol_table
* symtab
, Layout
* layout
,
1591 Sized_relobj_file
<32, false>* object
)
1593 if (this->got_mod_index_offset_
== -1U)
1595 gold_assert(symtab
!= NULL
&& layout
!= NULL
&& object
!= NULL
);
1596 Reloc_section
* rel_dyn
= this->rel_dyn_section(layout
);
1597 Output_data_got
<32, false>* got
= this->got_section(symtab
, layout
);
1598 unsigned int got_offset
= got
->add_constant(0);
1599 rel_dyn
->add_local(object
, 0, elfcpp::R_386_TLS_DTPMOD32
, got
,
1601 got
->add_constant(0);
1602 this->got_mod_index_offset_
= got_offset
;
1604 return this->got_mod_index_offset_
;
1607 // Optimize the TLS relocation type based on what we know about the
1608 // symbol. IS_FINAL is true if the final address of this symbol is
1609 // known at link time.
1611 tls::Tls_optimization
1612 Target_i386::optimize_tls_reloc(bool is_final
, int r_type
)
1614 // If we are generating a shared library, then we can't do anything
1616 if (parameters
->options().shared())
1617 return tls::TLSOPT_NONE
;
1621 case elfcpp::R_386_TLS_GD
:
1622 case elfcpp::R_386_TLS_GOTDESC
:
1623 case elfcpp::R_386_TLS_DESC_CALL
:
1624 // These are General-Dynamic which permits fully general TLS
1625 // access. Since we know that we are generating an executable,
1626 // we can convert this to Initial-Exec. If we also know that
1627 // this is a local symbol, we can further switch to Local-Exec.
1629 return tls::TLSOPT_TO_LE
;
1630 return tls::TLSOPT_TO_IE
;
1632 case elfcpp::R_386_TLS_LDM
:
1633 // This is Local-Dynamic, which refers to a local symbol in the
1634 // dynamic TLS block. Since we know that we generating an
1635 // executable, we can switch to Local-Exec.
1636 return tls::TLSOPT_TO_LE
;
1638 case elfcpp::R_386_TLS_LDO_32
:
1639 // Another type of Local-Dynamic relocation.
1640 return tls::TLSOPT_TO_LE
;
1642 case elfcpp::R_386_TLS_IE
:
1643 case elfcpp::R_386_TLS_GOTIE
:
1644 case elfcpp::R_386_TLS_IE_32
:
1645 // These are Initial-Exec relocs which get the thread offset
1646 // from the GOT. If we know that we are linking against the
1647 // local symbol, we can switch to Local-Exec, which links the
1648 // thread offset into the instruction.
1650 return tls::TLSOPT_TO_LE
;
1651 return tls::TLSOPT_NONE
;
1653 case elfcpp::R_386_TLS_LE
:
1654 case elfcpp::R_386_TLS_LE_32
:
1655 // When we already have Local-Exec, there is nothing further we
1657 return tls::TLSOPT_NONE
;
1664 // Get the Reference_flags for a particular relocation.
1667 Target_i386::Scan::get_reference_flags(unsigned int r_type
)
1671 case elfcpp::R_386_NONE
:
1672 case elfcpp::R_386_GNU_VTINHERIT
:
1673 case elfcpp::R_386_GNU_VTENTRY
:
1674 case elfcpp::R_386_GOTPC
:
1675 // No symbol reference.
1678 case elfcpp::R_386_32
:
1679 case elfcpp::R_386_16
:
1680 case elfcpp::R_386_8
:
1681 return Symbol::ABSOLUTE_REF
;
1683 case elfcpp::R_386_PC32
:
1684 case elfcpp::R_386_PC16
:
1685 case elfcpp::R_386_PC8
:
1686 case elfcpp::R_386_GOTOFF
:
1687 return Symbol::RELATIVE_REF
;
1689 case elfcpp::R_386_PLT32
:
1690 return Symbol::FUNCTION_CALL
| Symbol::RELATIVE_REF
;
1692 case elfcpp::R_386_GOT32
:
1694 return Symbol::ABSOLUTE_REF
;
1696 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1697 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
1698 case elfcpp::R_386_TLS_DESC_CALL
:
1699 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1700 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1701 case elfcpp::R_386_TLS_IE
: // Initial-exec
1702 case elfcpp::R_386_TLS_IE_32
:
1703 case elfcpp::R_386_TLS_GOTIE
:
1704 case elfcpp::R_386_TLS_LE
: // Local-exec
1705 case elfcpp::R_386_TLS_LE_32
:
1706 return Symbol::TLS_REF
;
1708 case elfcpp::R_386_COPY
:
1709 case elfcpp::R_386_GLOB_DAT
:
1710 case elfcpp::R_386_JUMP_SLOT
:
1711 case elfcpp::R_386_RELATIVE
:
1712 case elfcpp::R_386_IRELATIVE
:
1713 case elfcpp::R_386_TLS_TPOFF
:
1714 case elfcpp::R_386_TLS_DTPMOD32
:
1715 case elfcpp::R_386_TLS_DTPOFF32
:
1716 case elfcpp::R_386_TLS_TPOFF32
:
1717 case elfcpp::R_386_TLS_DESC
:
1718 case elfcpp::R_386_32PLT
:
1719 case elfcpp::R_386_TLS_GD_32
:
1720 case elfcpp::R_386_TLS_GD_PUSH
:
1721 case elfcpp::R_386_TLS_GD_CALL
:
1722 case elfcpp::R_386_TLS_GD_POP
:
1723 case elfcpp::R_386_TLS_LDM_32
:
1724 case elfcpp::R_386_TLS_LDM_PUSH
:
1725 case elfcpp::R_386_TLS_LDM_CALL
:
1726 case elfcpp::R_386_TLS_LDM_POP
:
1727 case elfcpp::R_386_USED_BY_INTEL_200
:
1729 // Not expected. We will give an error later.
1734 // Report an unsupported relocation against a local symbol.
1737 Target_i386::Scan::unsupported_reloc_local(Sized_relobj_file
<32, false>* object
,
1738 unsigned int r_type
)
1740 gold_error(_("%s: unsupported reloc %u against local symbol"),
1741 object
->name().c_str(), r_type
);
1744 // Return whether we need to make a PLT entry for a relocation of a
1745 // given type against a STT_GNU_IFUNC symbol.
1748 Target_i386::Scan::reloc_needs_plt_for_ifunc(
1749 Sized_relobj_file
<32, false>* object
,
1750 unsigned int r_type
)
1752 int flags
= Scan::get_reference_flags(r_type
);
1753 if (flags
& Symbol::TLS_REF
)
1754 gold_error(_("%s: unsupported TLS reloc %u for IFUNC symbol"),
1755 object
->name().c_str(), r_type
);
1759 // Scan a relocation for a local symbol.
1762 Target_i386::Scan::local(Symbol_table
* symtab
,
1764 Target_i386
* target
,
1765 Sized_relobj_file
<32, false>* object
,
1766 unsigned int data_shndx
,
1767 Output_section
* output_section
,
1768 const elfcpp::Rel
<32, false>& reloc
,
1769 unsigned int r_type
,
1770 const elfcpp::Sym
<32, false>& lsym
,
1776 // A local STT_GNU_IFUNC symbol may require a PLT entry.
1777 if (lsym
.get_st_type() == elfcpp::STT_GNU_IFUNC
1778 && this->reloc_needs_plt_for_ifunc(object
, r_type
))
1780 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1781 target
->make_local_ifunc_plt_entry(symtab
, layout
, object
, r_sym
);
1786 case elfcpp::R_386_NONE
:
1787 case elfcpp::R_386_GNU_VTINHERIT
:
1788 case elfcpp::R_386_GNU_VTENTRY
:
1791 case elfcpp::R_386_32
:
1792 // If building a shared library (or a position-independent
1793 // executable), we need to create a dynamic relocation for
1794 // this location. The relocation applied at link time will
1795 // apply the link-time value, so we flag the location with
1796 // an R_386_RELATIVE relocation so the dynamic loader can
1797 // relocate it easily.
1798 if (parameters
->options().output_is_position_independent())
1800 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1801 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1802 rel_dyn
->add_local_relative(object
, r_sym
, elfcpp::R_386_RELATIVE
,
1803 output_section
, data_shndx
,
1804 reloc
.get_r_offset());
1808 case elfcpp::R_386_16
:
1809 case elfcpp::R_386_8
:
1810 // If building a shared library (or a position-independent
1811 // executable), we need to create a dynamic relocation for
1812 // this location. Because the addend needs to remain in the
1813 // data section, we need to be careful not to apply this
1814 // relocation statically.
1815 if (parameters
->options().output_is_position_independent())
1817 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1818 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1819 if (lsym
.get_st_type() != elfcpp::STT_SECTION
)
1820 rel_dyn
->add_local(object
, r_sym
, r_type
, output_section
,
1821 data_shndx
, reloc
.get_r_offset());
1824 gold_assert(lsym
.get_st_value() == 0);
1825 unsigned int shndx
= lsym
.get_st_shndx();
1827 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
,
1830 object
->error(_("section symbol %u has bad shndx %u"),
1833 rel_dyn
->add_local_section(object
, shndx
,
1834 r_type
, output_section
,
1835 data_shndx
, reloc
.get_r_offset());
1840 case elfcpp::R_386_PC32
:
1841 case elfcpp::R_386_PC16
:
1842 case elfcpp::R_386_PC8
:
1845 case elfcpp::R_386_PLT32
:
1846 // Since we know this is a local symbol, we can handle this as a
1850 case elfcpp::R_386_GOTOFF
:
1851 case elfcpp::R_386_GOTPC
:
1852 // We need a GOT section.
1853 target
->got_section(symtab
, layout
);
1856 case elfcpp::R_386_GOT32
:
1858 // We need GOT section.
1859 Output_data_got
<32, false>* got
= target
->got_section(symtab
, layout
);
1861 // If the relocation symbol isn't IFUNC,
1862 // and is local, then we will convert
1863 // mov foo@GOT(%reg), %reg
1865 // lea foo@GOTOFF(%reg), %reg
1866 // in Relocate::relocate.
1867 if (reloc
.get_r_offset() >= 2
1868 && lsym
.get_st_type() != elfcpp::STT_GNU_IFUNC
)
1870 section_size_type stype
;
1871 const unsigned char* view
= object
->section_contents(data_shndx
,
1873 if (view
[reloc
.get_r_offset() - 2] == 0x8b)
1877 // Otherwise, the symbol requires a GOT entry.
1878 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1880 // For a STT_GNU_IFUNC symbol we want the PLT offset. That
1881 // lets function pointers compare correctly with shared
1882 // libraries. Otherwise we would need an IRELATIVE reloc.
1884 if (lsym
.get_st_type() == elfcpp::STT_GNU_IFUNC
)
1885 is_new
= got
->add_local_plt(object
, r_sym
, GOT_TYPE_STANDARD
);
1887 is_new
= got
->add_local(object
, r_sym
, GOT_TYPE_STANDARD
);
1890 // If we are generating a shared object, we need to add a
1891 // dynamic RELATIVE relocation for this symbol's GOT entry.
1892 if (parameters
->options().output_is_position_independent())
1894 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1895 unsigned int got_offset
=
1896 object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
);
1897 rel_dyn
->add_local_relative(object
, r_sym
,
1898 elfcpp::R_386_RELATIVE
,
1905 // These are relocations which should only be seen by the
1906 // dynamic linker, and should never be seen here.
1907 case elfcpp::R_386_COPY
:
1908 case elfcpp::R_386_GLOB_DAT
:
1909 case elfcpp::R_386_JUMP_SLOT
:
1910 case elfcpp::R_386_RELATIVE
:
1911 case elfcpp::R_386_IRELATIVE
:
1912 case elfcpp::R_386_TLS_TPOFF
:
1913 case elfcpp::R_386_TLS_DTPMOD32
:
1914 case elfcpp::R_386_TLS_DTPOFF32
:
1915 case elfcpp::R_386_TLS_TPOFF32
:
1916 case elfcpp::R_386_TLS_DESC
:
1917 gold_error(_("%s: unexpected reloc %u in object file"),
1918 object
->name().c_str(), r_type
);
1921 // These are initial TLS relocs, which are expected when
1923 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1924 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
1925 case elfcpp::R_386_TLS_DESC_CALL
:
1926 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1927 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1928 case elfcpp::R_386_TLS_IE
: // Initial-exec
1929 case elfcpp::R_386_TLS_IE_32
:
1930 case elfcpp::R_386_TLS_GOTIE
:
1931 case elfcpp::R_386_TLS_LE
: // Local-exec
1932 case elfcpp::R_386_TLS_LE_32
:
1934 bool output_is_shared
= parameters
->options().shared();
1935 const tls::Tls_optimization optimized_type
1936 = Target_i386::optimize_tls_reloc(!output_is_shared
, r_type
);
1939 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1940 if (optimized_type
== tls::TLSOPT_NONE
)
1942 // Create a pair of GOT entries for the module index and
1943 // dtv-relative offset.
1944 Output_data_got
<32, false>* got
1945 = target
->got_section(symtab
, layout
);
1946 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1947 unsigned int shndx
= lsym
.get_st_shndx();
1949 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
, &is_ordinary
);
1951 object
->error(_("local symbol %u has bad shndx %u"),
1954 got
->add_local_pair_with_rel(object
, r_sym
, shndx
,
1956 target
->rel_dyn_section(layout
),
1957 elfcpp::R_386_TLS_DTPMOD32
);
1959 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1960 unsupported_reloc_local(object
, r_type
);
1963 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva)
1964 target
->define_tls_base_symbol(symtab
, layout
);
1965 if (optimized_type
== tls::TLSOPT_NONE
)
1967 // Create a double GOT entry with an R_386_TLS_DESC
1968 // reloc. The R_386_TLS_DESC reloc is resolved
1969 // lazily, so the GOT entry needs to be in an area in
1970 // .got.plt, not .got. Call got_section to make sure
1971 // the section has been created.
1972 target
->got_section(symtab
, layout
);
1973 Output_data_got
<32, false>* got
= target
->got_tlsdesc_section();
1974 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1975 if (!object
->local_has_got_offset(r_sym
, GOT_TYPE_TLS_DESC
))
1977 unsigned int got_offset
= got
->add_constant(0);
1978 // The local symbol value is stored in the second
1980 got
->add_local(object
, r_sym
, GOT_TYPE_TLS_DESC
);
1981 // That set the GOT offset of the local symbol to
1982 // point to the second entry, but we want it to
1983 // point to the first.
1984 object
->set_local_got_offset(r_sym
, GOT_TYPE_TLS_DESC
,
1986 Reloc_section
* rt
= target
->rel_tls_desc_section(layout
);
1987 rt
->add_absolute(elfcpp::R_386_TLS_DESC
, got
, got_offset
);
1990 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1991 unsupported_reloc_local(object
, r_type
);
1994 case elfcpp::R_386_TLS_DESC_CALL
:
1997 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1998 if (optimized_type
== tls::TLSOPT_NONE
)
2000 // Create a GOT entry for the module index.
2001 target
->got_mod_index_entry(symtab
, layout
, object
);
2003 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2004 unsupported_reloc_local(object
, r_type
);
2007 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
2010 case elfcpp::R_386_TLS_IE
: // Initial-exec
2011 case elfcpp::R_386_TLS_IE_32
:
2012 case elfcpp::R_386_TLS_GOTIE
:
2013 layout
->set_has_static_tls();
2014 if (optimized_type
== tls::TLSOPT_NONE
)
2016 // For the R_386_TLS_IE relocation, we need to create a
2017 // dynamic relocation when building a shared library.
2018 if (r_type
== elfcpp::R_386_TLS_IE
2019 && parameters
->options().shared())
2021 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
2023 = elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
2024 rel_dyn
->add_local_relative(object
, r_sym
,
2025 elfcpp::R_386_RELATIVE
,
2026 output_section
, data_shndx
,
2027 reloc
.get_r_offset());
2029 // Create a GOT entry for the tp-relative offset.
2030 Output_data_got
<32, false>* got
2031 = target
->got_section(symtab
, layout
);
2032 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
2033 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_IE_32
2034 ? elfcpp::R_386_TLS_TPOFF32
2035 : elfcpp::R_386_TLS_TPOFF
);
2036 unsigned int got_type
= (r_type
== elfcpp::R_386_TLS_IE_32
2037 ? GOT_TYPE_TLS_OFFSET
2038 : GOT_TYPE_TLS_NOFFSET
);
2039 got
->add_local_with_rel(object
, r_sym
, got_type
,
2040 target
->rel_dyn_section(layout
),
2043 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2044 unsupported_reloc_local(object
, r_type
);
2047 case elfcpp::R_386_TLS_LE
: // Local-exec
2048 case elfcpp::R_386_TLS_LE_32
:
2049 layout
->set_has_static_tls();
2050 if (output_is_shared
)
2052 // We need to create a dynamic relocation.
2053 gold_assert(lsym
.get_st_type() != elfcpp::STT_SECTION
);
2054 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
2055 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_LE_32
2056 ? elfcpp::R_386_TLS_TPOFF32
2057 : elfcpp::R_386_TLS_TPOFF
);
2058 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
2059 rel_dyn
->add_local(object
, r_sym
, dyn_r_type
, output_section
,
2060 data_shndx
, reloc
.get_r_offset());
2070 case elfcpp::R_386_32PLT
:
2071 case elfcpp::R_386_TLS_GD_32
:
2072 case elfcpp::R_386_TLS_GD_PUSH
:
2073 case elfcpp::R_386_TLS_GD_CALL
:
2074 case elfcpp::R_386_TLS_GD_POP
:
2075 case elfcpp::R_386_TLS_LDM_32
:
2076 case elfcpp::R_386_TLS_LDM_PUSH
:
2077 case elfcpp::R_386_TLS_LDM_CALL
:
2078 case elfcpp::R_386_TLS_LDM_POP
:
2079 case elfcpp::R_386_USED_BY_INTEL_200
:
2081 unsupported_reloc_local(object
, r_type
);
2086 // Report an unsupported relocation against a global symbol.
2089 Target_i386::Scan::unsupported_reloc_global(
2090 Sized_relobj_file
<32, false>* object
,
2091 unsigned int r_type
,
2094 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
2095 object
->name().c_str(), r_type
, gsym
->demangled_name().c_str());
2099 Target_i386::Scan::possible_function_pointer_reloc(unsigned int r_type
)
2103 case elfcpp::R_386_32
:
2104 case elfcpp::R_386_16
:
2105 case elfcpp::R_386_8
:
2106 case elfcpp::R_386_GOTOFF
:
2107 case elfcpp::R_386_GOT32
:
2118 Target_i386::Scan::local_reloc_may_be_function_pointer(
2122 Sized_relobj_file
<32, false>* ,
2125 const elfcpp::Rel
<32, false>& ,
2126 unsigned int r_type
,
2127 const elfcpp::Sym
<32, false>&)
2129 return possible_function_pointer_reloc(r_type
);
2133 Target_i386::Scan::global_reloc_may_be_function_pointer(
2137 Sized_relobj_file
<32, false>* ,
2140 const elfcpp::Rel
<32, false>& ,
2141 unsigned int r_type
,
2144 return possible_function_pointer_reloc(r_type
);
2147 // Scan a relocation for a global symbol.
2150 Target_i386::Scan::global(Symbol_table
* symtab
,
2152 Target_i386
* target
,
2153 Sized_relobj_file
<32, false>* object
,
2154 unsigned int data_shndx
,
2155 Output_section
* output_section
,
2156 const elfcpp::Rel
<32, false>& reloc
,
2157 unsigned int r_type
,
2160 // A STT_GNU_IFUNC symbol may require a PLT entry.
2161 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
2162 && this->reloc_needs_plt_for_ifunc(object
, r_type
))
2163 target
->make_plt_entry(symtab
, layout
, gsym
);
2167 case elfcpp::R_386_NONE
:
2168 case elfcpp::R_386_GNU_VTINHERIT
:
2169 case elfcpp::R_386_GNU_VTENTRY
:
2172 case elfcpp::R_386_32
:
2173 case elfcpp::R_386_16
:
2174 case elfcpp::R_386_8
:
2176 // Make a PLT entry if necessary.
2177 if (gsym
->needs_plt_entry())
2179 target
->make_plt_entry(symtab
, layout
, gsym
);
2180 // Since this is not a PC-relative relocation, we may be
2181 // taking the address of a function. In that case we need to
2182 // set the entry in the dynamic symbol table to the address of
2184 if (gsym
->is_from_dynobj() && !parameters
->options().shared())
2185 gsym
->set_needs_dynsym_value();
2187 // Make a dynamic relocation if necessary.
2188 if (gsym
->needs_dynamic_reloc(Scan::get_reference_flags(r_type
)))
2190 if (!parameters
->options().output_is_position_independent()
2191 && gsym
->may_need_copy_reloc())
2193 target
->copy_reloc(symtab
, layout
, object
,
2194 data_shndx
, output_section
, gsym
, reloc
);
2196 else if (r_type
== elfcpp::R_386_32
2197 && gsym
->type() == elfcpp::STT_GNU_IFUNC
2198 && gsym
->can_use_relative_reloc(false)
2199 && !gsym
->is_from_dynobj()
2200 && !gsym
->is_undefined()
2201 && !gsym
->is_preemptible())
2203 // Use an IRELATIVE reloc for a locally defined
2204 // STT_GNU_IFUNC symbol. This makes a function
2205 // address in a PIE executable match the address in a
2206 // shared library that it links against.
2207 Reloc_section
* rel_dyn
= target
->rel_irelative_section(layout
);
2208 rel_dyn
->add_symbolless_global_addend(gsym
,
2209 elfcpp::R_386_IRELATIVE
,
2212 reloc
.get_r_offset());
2214 else if (r_type
== elfcpp::R_386_32
2215 && gsym
->can_use_relative_reloc(false))
2217 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
2218 rel_dyn
->add_global_relative(gsym
, elfcpp::R_386_RELATIVE
,
2219 output_section
, object
,
2220 data_shndx
, reloc
.get_r_offset());
2224 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
2225 rel_dyn
->add_global(gsym
, r_type
, output_section
, object
,
2226 data_shndx
, reloc
.get_r_offset());
2232 case elfcpp::R_386_PC32
:
2233 case elfcpp::R_386_PC16
:
2234 case elfcpp::R_386_PC8
:
2236 // Make a PLT entry if necessary.
2237 if (gsym
->needs_plt_entry())
2239 // These relocations are used for function calls only in
2240 // non-PIC code. For a 32-bit relocation in a shared library,
2241 // we'll need a text relocation anyway, so we can skip the
2242 // PLT entry and let the dynamic linker bind the call directly
2243 // to the target. For smaller relocations, we should use a
2244 // PLT entry to ensure that the call can reach.
2245 if (!parameters
->options().shared()
2246 || r_type
!= elfcpp::R_386_PC32
)
2247 target
->make_plt_entry(symtab
, layout
, gsym
);
2249 // Make a dynamic relocation if necessary.
2250 if (gsym
->needs_dynamic_reloc(Scan::get_reference_flags(r_type
)))
2252 if (parameters
->options().output_is_executable()
2253 && gsym
->may_need_copy_reloc())
2255 target
->copy_reloc(symtab
, layout
, object
,
2256 data_shndx
, output_section
, gsym
, reloc
);
2260 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
2261 rel_dyn
->add_global(gsym
, r_type
, output_section
, object
,
2262 data_shndx
, reloc
.get_r_offset());
2268 case elfcpp::R_386_GOT32
:
2270 // The symbol requires a GOT section.
2271 Output_data_got
<32, false>* got
= target
->got_section(symtab
, layout
);
2273 // If we convert this from
2274 // mov foo@GOT(%reg), %reg
2276 // lea foo@GOTOFF(%reg), %reg
2277 // in Relocate::relocate, then there is nothing to do here.
2278 if (reloc
.get_r_offset() >= 2
2279 && Target_i386::can_convert_mov_to_lea(gsym
))
2281 section_size_type stype
;
2282 const unsigned char* view
= object
->section_contents(data_shndx
,
2284 if (view
[reloc
.get_r_offset() - 2] == 0x8b)
2288 if (gsym
->final_value_is_known())
2290 // For a STT_GNU_IFUNC symbol we want the PLT address.
2291 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
)
2292 got
->add_global_plt(gsym
, GOT_TYPE_STANDARD
);
2294 got
->add_global(gsym
, GOT_TYPE_STANDARD
);
2298 // If this symbol is not fully resolved, we need to add a
2299 // GOT entry with a dynamic relocation.
2300 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
2302 // Use a GLOB_DAT rather than a RELATIVE reloc if:
2304 // 1) The symbol may be defined in some other module.
2306 // 2) We are building a shared library and this is a
2307 // protected symbol; using GLOB_DAT means that the dynamic
2308 // linker can use the address of the PLT in the main
2309 // executable when appropriate so that function address
2310 // comparisons work.
2312 // 3) This is a STT_GNU_IFUNC symbol in position dependent
2313 // code, again so that function address comparisons work.
2314 if (gsym
->is_from_dynobj()
2315 || gsym
->is_undefined()
2316 || gsym
->is_preemptible()
2317 || (gsym
->visibility() == elfcpp::STV_PROTECTED
2318 && parameters
->options().shared())
2319 || (gsym
->type() == elfcpp::STT_GNU_IFUNC
2320 && parameters
->options().output_is_position_independent()))
2321 got
->add_global_with_rel(gsym
, GOT_TYPE_STANDARD
,
2322 rel_dyn
, elfcpp::R_386_GLOB_DAT
);
2325 // For a STT_GNU_IFUNC symbol we want to write the PLT
2326 // offset into the GOT, so that function pointer
2327 // comparisons work correctly.
2329 if (gsym
->type() != elfcpp::STT_GNU_IFUNC
)
2330 is_new
= got
->add_global(gsym
, GOT_TYPE_STANDARD
);
2333 is_new
= got
->add_global_plt(gsym
, GOT_TYPE_STANDARD
);
2334 // Tell the dynamic linker to use the PLT address
2335 // when resolving relocations.
2336 if (gsym
->is_from_dynobj()
2337 && !parameters
->options().shared())
2338 gsym
->set_needs_dynsym_value();
2342 unsigned int got_off
= gsym
->got_offset(GOT_TYPE_STANDARD
);
2343 rel_dyn
->add_global_relative(gsym
, elfcpp::R_386_RELATIVE
,
2351 case elfcpp::R_386_PLT32
:
2352 // If the symbol is fully resolved, this is just a PC32 reloc.
2353 // Otherwise we need a PLT entry.
2354 if (gsym
->final_value_is_known())
2356 // If building a shared library, we can also skip the PLT entry
2357 // if the symbol is defined in the output file and is protected
2359 if (gsym
->is_defined()
2360 && !gsym
->is_from_dynobj()
2361 && !gsym
->is_preemptible())
2363 target
->make_plt_entry(symtab
, layout
, gsym
);
2366 case elfcpp::R_386_GOTOFF
:
2367 case elfcpp::R_386_GOTPC
:
2368 // We need a GOT section.
2369 target
->got_section(symtab
, layout
);
2372 // These are relocations which should only be seen by the
2373 // dynamic linker, and should never be seen here.
2374 case elfcpp::R_386_COPY
:
2375 case elfcpp::R_386_GLOB_DAT
:
2376 case elfcpp::R_386_JUMP_SLOT
:
2377 case elfcpp::R_386_RELATIVE
:
2378 case elfcpp::R_386_IRELATIVE
:
2379 case elfcpp::R_386_TLS_TPOFF
:
2380 case elfcpp::R_386_TLS_DTPMOD32
:
2381 case elfcpp::R_386_TLS_DTPOFF32
:
2382 case elfcpp::R_386_TLS_TPOFF32
:
2383 case elfcpp::R_386_TLS_DESC
:
2384 gold_error(_("%s: unexpected reloc %u in object file"),
2385 object
->name().c_str(), r_type
);
2388 // These are initial tls relocs, which are expected when
2390 case elfcpp::R_386_TLS_GD
: // Global-dynamic
2391 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
2392 case elfcpp::R_386_TLS_DESC_CALL
:
2393 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
2394 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
2395 case elfcpp::R_386_TLS_IE
: // Initial-exec
2396 case elfcpp::R_386_TLS_IE_32
:
2397 case elfcpp::R_386_TLS_GOTIE
:
2398 case elfcpp::R_386_TLS_LE
: // Local-exec
2399 case elfcpp::R_386_TLS_LE_32
:
2401 const bool is_final
= gsym
->final_value_is_known();
2402 const tls::Tls_optimization optimized_type
2403 = Target_i386::optimize_tls_reloc(is_final
, r_type
);
2406 case elfcpp::R_386_TLS_GD
: // Global-dynamic
2407 if (optimized_type
== tls::TLSOPT_NONE
)
2409 // Create a pair of GOT entries for the module index and
2410 // dtv-relative offset.
2411 Output_data_got
<32, false>* got
2412 = target
->got_section(symtab
, layout
);
2413 got
->add_global_pair_with_rel(gsym
, GOT_TYPE_TLS_PAIR
,
2414 target
->rel_dyn_section(layout
),
2415 elfcpp::R_386_TLS_DTPMOD32
,
2416 elfcpp::R_386_TLS_DTPOFF32
);
2418 else if (optimized_type
== tls::TLSOPT_TO_IE
)
2420 // Create a GOT entry for the tp-relative offset.
2421 Output_data_got
<32, false>* got
2422 = target
->got_section(symtab
, layout
);
2423 got
->add_global_with_rel(gsym
, GOT_TYPE_TLS_NOFFSET
,
2424 target
->rel_dyn_section(layout
),
2425 elfcpp::R_386_TLS_TPOFF
);
2427 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2428 unsupported_reloc_global(object
, r_type
, gsym
);
2431 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (~oliva url)
2432 target
->define_tls_base_symbol(symtab
, layout
);
2433 if (optimized_type
== tls::TLSOPT_NONE
)
2435 // Create a double GOT entry with an R_386_TLS_DESC
2436 // reloc. The R_386_TLS_DESC reloc is resolved
2437 // lazily, so the GOT entry needs to be in an area in
2438 // .got.plt, not .got. Call got_section to make sure
2439 // the section has been created.
2440 target
->got_section(symtab
, layout
);
2441 Output_data_got
<32, false>* got
= target
->got_tlsdesc_section();
2442 Reloc_section
* rt
= target
->rel_tls_desc_section(layout
);
2443 got
->add_global_pair_with_rel(gsym
, GOT_TYPE_TLS_DESC
, rt
,
2444 elfcpp::R_386_TLS_DESC
, 0);
2446 else if (optimized_type
== tls::TLSOPT_TO_IE
)
2448 // Create a GOT entry for the tp-relative offset.
2449 Output_data_got
<32, false>* got
2450 = target
->got_section(symtab
, layout
);
2451 got
->add_global_with_rel(gsym
, GOT_TYPE_TLS_NOFFSET
,
2452 target
->rel_dyn_section(layout
),
2453 elfcpp::R_386_TLS_TPOFF
);
2455 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2456 unsupported_reloc_global(object
, r_type
, gsym
);
2459 case elfcpp::R_386_TLS_DESC_CALL
:
2462 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
2463 if (optimized_type
== tls::TLSOPT_NONE
)
2465 // Create a GOT entry for the module index.
2466 target
->got_mod_index_entry(symtab
, layout
, object
);
2468 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2469 unsupported_reloc_global(object
, r_type
, gsym
);
2472 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
2475 case elfcpp::R_386_TLS_IE
: // Initial-exec
2476 case elfcpp::R_386_TLS_IE_32
:
2477 case elfcpp::R_386_TLS_GOTIE
:
2478 layout
->set_has_static_tls();
2479 if (optimized_type
== tls::TLSOPT_NONE
)
2481 // For the R_386_TLS_IE relocation, we need to create a
2482 // dynamic relocation when building a shared library.
2483 if (r_type
== elfcpp::R_386_TLS_IE
2484 && parameters
->options().shared())
2486 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
2487 rel_dyn
->add_global_relative(gsym
, elfcpp::R_386_RELATIVE
,
2488 output_section
, object
,
2490 reloc
.get_r_offset());
2492 // Create a GOT entry for the tp-relative offset.
2493 Output_data_got
<32, false>* got
2494 = target
->got_section(symtab
, layout
);
2495 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_IE_32
2496 ? elfcpp::R_386_TLS_TPOFF32
2497 : elfcpp::R_386_TLS_TPOFF
);
2498 unsigned int got_type
= (r_type
== elfcpp::R_386_TLS_IE_32
2499 ? GOT_TYPE_TLS_OFFSET
2500 : GOT_TYPE_TLS_NOFFSET
);
2501 got
->add_global_with_rel(gsym
, got_type
,
2502 target
->rel_dyn_section(layout
),
2505 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2506 unsupported_reloc_global(object
, r_type
, gsym
);
2509 case elfcpp::R_386_TLS_LE
: // Local-exec
2510 case elfcpp::R_386_TLS_LE_32
:
2511 layout
->set_has_static_tls();
2512 if (parameters
->options().shared())
2514 // We need to create a dynamic relocation.
2515 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_LE_32
2516 ? elfcpp::R_386_TLS_TPOFF32
2517 : elfcpp::R_386_TLS_TPOFF
);
2518 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
2519 rel_dyn
->add_global(gsym
, dyn_r_type
, output_section
, object
,
2520 data_shndx
, reloc
.get_r_offset());
2530 case elfcpp::R_386_32PLT
:
2531 case elfcpp::R_386_TLS_GD_32
:
2532 case elfcpp::R_386_TLS_GD_PUSH
:
2533 case elfcpp::R_386_TLS_GD_CALL
:
2534 case elfcpp::R_386_TLS_GD_POP
:
2535 case elfcpp::R_386_TLS_LDM_32
:
2536 case elfcpp::R_386_TLS_LDM_PUSH
:
2537 case elfcpp::R_386_TLS_LDM_CALL
:
2538 case elfcpp::R_386_TLS_LDM_POP
:
2539 case elfcpp::R_386_USED_BY_INTEL_200
:
2541 unsupported_reloc_global(object
, r_type
, gsym
);
2546 // Process relocations for gc.
2549 Target_i386::gc_process_relocs(Symbol_table
* symtab
,
2551 Sized_relobj_file
<32, false>* object
,
2552 unsigned int data_shndx
,
2554 const unsigned char* prelocs
,
2556 Output_section
* output_section
,
2557 bool needs_special_offset_handling
,
2558 size_t local_symbol_count
,
2559 const unsigned char* plocal_symbols
)
2561 gold::gc_process_relocs
<32, false, Target_i386
, elfcpp::SHT_REL
,
2563 Target_i386::Relocatable_size_for_reloc
>(
2572 needs_special_offset_handling
,
2577 // Scan relocations for a section.
2580 Target_i386::scan_relocs(Symbol_table
* symtab
,
2582 Sized_relobj_file
<32, false>* object
,
2583 unsigned int data_shndx
,
2584 unsigned int sh_type
,
2585 const unsigned char* prelocs
,
2587 Output_section
* output_section
,
2588 bool needs_special_offset_handling
,
2589 size_t local_symbol_count
,
2590 const unsigned char* plocal_symbols
)
2592 if (sh_type
== elfcpp::SHT_RELA
)
2594 gold_error(_("%s: unsupported RELA reloc section"),
2595 object
->name().c_str());
2599 gold::scan_relocs
<32, false, Target_i386
, elfcpp::SHT_REL
,
2609 needs_special_offset_handling
,
2614 // Finalize the sections.
2617 Target_i386::do_finalize_sections(
2619 const Input_objects
*,
2620 Symbol_table
* symtab
)
2622 const Reloc_section
* rel_plt
= (this->plt_
== NULL
2624 : this->plt_
->rel_plt());
2625 layout
->add_target_dynamic_tags(true, this->got_plt_
, rel_plt
,
2626 this->rel_dyn_
, true, false);
2628 // Emit any relocs we saved in an attempt to avoid generating COPY
2630 if (this->copy_relocs_
.any_saved_relocs())
2631 this->copy_relocs_
.emit(this->rel_dyn_section(layout
));
2633 // Set the size of the _GLOBAL_OFFSET_TABLE_ symbol to the size of
2634 // the .got.plt section.
2635 Symbol
* sym
= this->global_offset_table_
;
2638 uint32_t data_size
= this->got_plt_
->current_data_size();
2639 symtab
->get_sized_symbol
<32>(sym
)->set_symsize(data_size
);
2642 if (parameters
->doing_static_link()
2643 && (this->plt_
== NULL
|| !this->plt_
->has_irelative_section()))
2645 // If linking statically, make sure that the __rel_iplt symbols
2646 // were defined if necessary, even if we didn't create a PLT.
2647 static const Define_symbol_in_segment syms
[] =
2650 "__rel_iplt_start", // name
2651 elfcpp::PT_LOAD
, // segment_type
2652 elfcpp::PF_W
, // segment_flags_set
2653 elfcpp::PF(0), // segment_flags_clear
2656 elfcpp::STT_NOTYPE
, // type
2657 elfcpp::STB_GLOBAL
, // binding
2658 elfcpp::STV_HIDDEN
, // visibility
2660 Symbol::SEGMENT_START
, // offset_from_base
2664 "__rel_iplt_end", // name
2665 elfcpp::PT_LOAD
, // segment_type
2666 elfcpp::PF_W
, // segment_flags_set
2667 elfcpp::PF(0), // segment_flags_clear
2670 elfcpp::STT_NOTYPE
, // type
2671 elfcpp::STB_GLOBAL
, // binding
2672 elfcpp::STV_HIDDEN
, // visibility
2674 Symbol::SEGMENT_START
, // offset_from_base
2679 symtab
->define_symbols(layout
, 2, syms
,
2680 layout
->script_options()->saw_sections_clause());
2684 // Return whether a direct absolute static relocation needs to be applied.
2685 // In cases where Scan::local() or Scan::global() has created
2686 // a dynamic relocation other than R_386_RELATIVE, the addend
2687 // of the relocation is carried in the data, and we must not
2688 // apply the static relocation.
2691 Target_i386::Relocate::should_apply_static_reloc(const Sized_symbol
<32>* gsym
,
2692 unsigned int r_type
,
2694 Output_section
* output_section
)
2696 // If the output section is not allocated, then we didn't call
2697 // scan_relocs, we didn't create a dynamic reloc, and we must apply
2699 if ((output_section
->flags() & elfcpp::SHF_ALLOC
) == 0)
2702 int ref_flags
= Scan::get_reference_flags(r_type
);
2704 // For local symbols, we will have created a non-RELATIVE dynamic
2705 // relocation only if (a) the output is position independent,
2706 // (b) the relocation is absolute (not pc- or segment-relative), and
2707 // (c) the relocation is not 32 bits wide.
2709 return !(parameters
->options().output_is_position_independent()
2710 && (ref_flags
& Symbol::ABSOLUTE_REF
)
2713 // For global symbols, we use the same helper routines used in the
2714 // scan pass. If we did not create a dynamic relocation, or if we
2715 // created a RELATIVE dynamic relocation, we should apply the static
2717 bool has_dyn
= gsym
->needs_dynamic_reloc(ref_flags
);
2718 bool is_rel
= (ref_flags
& Symbol::ABSOLUTE_REF
)
2719 && gsym
->can_use_relative_reloc(ref_flags
2720 & Symbol::FUNCTION_CALL
);
2721 return !has_dyn
|| is_rel
;
2724 // Perform a relocation.
2727 Target_i386::Relocate::relocate(const Relocate_info
<32, false>* relinfo
,
2728 Target_i386
* target
,
2729 Output_section
* output_section
,
2731 const elfcpp::Rel
<32, false>& rel
,
2732 unsigned int r_type
,
2733 const Sized_symbol
<32>* gsym
,
2734 const Symbol_value
<32>* psymval
,
2735 unsigned char* view
,
2736 elfcpp::Elf_types
<32>::Elf_Addr address
,
2737 section_size_type view_size
)
2739 if (this->skip_call_tls_get_addr_
)
2741 if ((r_type
!= elfcpp::R_386_PLT32
2742 && r_type
!= elfcpp::R_386_PC32
)
2744 || strcmp(gsym
->name(), "___tls_get_addr") != 0)
2745 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2746 _("missing expected TLS relocation"));
2749 this->skip_call_tls_get_addr_
= false;
2757 const Sized_relobj_file
<32, false>* object
= relinfo
->object
;
2759 // Pick the value to use for symbols defined in shared objects.
2760 Symbol_value
<32> symval
;
2762 && gsym
->type() == elfcpp::STT_GNU_IFUNC
2763 && r_type
== elfcpp::R_386_32
2764 && gsym
->needs_dynamic_reloc(Scan::get_reference_flags(r_type
))
2765 && gsym
->can_use_relative_reloc(false)
2766 && !gsym
->is_from_dynobj()
2767 && !gsym
->is_undefined()
2768 && !gsym
->is_preemptible())
2770 // In this case we are generating a R_386_IRELATIVE reloc. We
2771 // want to use the real value of the symbol, not the PLT offset.
2773 else if (gsym
!= NULL
2774 && gsym
->use_plt_offset(Scan::get_reference_flags(r_type
)))
2776 symval
.set_output_value(target
->plt_address_for_global(gsym
));
2779 else if (gsym
== NULL
&& psymval
->is_ifunc_symbol())
2781 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
2782 if (object
->local_has_plt_offset(r_sym
))
2784 symval
.set_output_value(target
->plt_address_for_local(object
, r_sym
));
2791 case elfcpp::R_386_NONE
:
2792 case elfcpp::R_386_GNU_VTINHERIT
:
2793 case elfcpp::R_386_GNU_VTENTRY
:
2796 case elfcpp::R_386_32
:
2797 if (should_apply_static_reloc(gsym
, r_type
, true, output_section
))
2798 Relocate_functions
<32, false>::rel32(view
, object
, psymval
);
2801 case elfcpp::R_386_PC32
:
2802 if (should_apply_static_reloc(gsym
, r_type
, true, output_section
))
2803 Relocate_functions
<32, false>::pcrel32(view
, object
, psymval
, address
);
2806 case elfcpp::R_386_16
:
2807 if (should_apply_static_reloc(gsym
, r_type
, false, output_section
))
2808 Relocate_functions
<32, false>::rel16(view
, object
, psymval
);
2811 case elfcpp::R_386_PC16
:
2812 if (should_apply_static_reloc(gsym
, r_type
, false, output_section
))
2813 Relocate_functions
<32, false>::pcrel16(view
, object
, psymval
, address
);
2816 case elfcpp::R_386_8
:
2817 if (should_apply_static_reloc(gsym
, r_type
, false, output_section
))
2818 Relocate_functions
<32, false>::rel8(view
, object
, psymval
);
2821 case elfcpp::R_386_PC8
:
2822 if (should_apply_static_reloc(gsym
, r_type
, false, output_section
))
2823 Relocate_functions
<32, false>::pcrel8(view
, object
, psymval
, address
);
2826 case elfcpp::R_386_PLT32
:
2827 gold_assert(gsym
== NULL
2828 || gsym
->has_plt_offset()
2829 || gsym
->final_value_is_known()
2830 || (gsym
->is_defined()
2831 && !gsym
->is_from_dynobj()
2832 && !gsym
->is_preemptible()));
2833 Relocate_functions
<32, false>::pcrel32(view
, object
, psymval
, address
);
2836 case elfcpp::R_386_GOT32
:
2838 // mov foo@GOT(%reg), %reg
2840 // lea foo@GOTOFF(%reg), %reg
2842 if (rel
.get_r_offset() >= 2
2844 && ((gsym
== NULL
&& !psymval
->is_ifunc_symbol())
2846 && Target_i386::can_convert_mov_to_lea(gsym
))))
2849 elfcpp::Elf_types
<32>::Elf_Addr value
;
2850 value
= (psymval
->value(object
, 0)
2851 - target
->got_plt_section()->address());
2852 Relocate_functions
<32, false>::rel32(view
, value
);
2856 // The GOT pointer points to the end of the GOT section.
2857 // We need to subtract the size of the GOT section to get
2858 // the actual offset to use in the relocation.
2859 unsigned int got_offset
= 0;
2862 gold_assert(gsym
->has_got_offset(GOT_TYPE_STANDARD
));
2863 got_offset
= (gsym
->got_offset(GOT_TYPE_STANDARD
)
2864 - target
->got_size());
2868 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
2869 gold_assert(object
->local_has_got_offset(r_sym
, GOT_TYPE_STANDARD
));
2870 got_offset
= (object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
)
2871 - target
->got_size());
2873 Relocate_functions
<32, false>::rel32(view
, got_offset
);
2877 case elfcpp::R_386_GOTOFF
:
2879 elfcpp::Elf_types
<32>::Elf_Addr value
;
2880 value
= (psymval
->value(object
, 0)
2881 - target
->got_plt_section()->address());
2882 Relocate_functions
<32, false>::rel32(view
, value
);
2886 case elfcpp::R_386_GOTPC
:
2888 elfcpp::Elf_types
<32>::Elf_Addr value
;
2889 value
= target
->got_plt_section()->address();
2890 Relocate_functions
<32, false>::pcrel32(view
, value
, address
);
2894 case elfcpp::R_386_COPY
:
2895 case elfcpp::R_386_GLOB_DAT
:
2896 case elfcpp::R_386_JUMP_SLOT
:
2897 case elfcpp::R_386_RELATIVE
:
2898 case elfcpp::R_386_IRELATIVE
:
2899 // These are outstanding tls relocs, which are unexpected when
2901 case elfcpp::R_386_TLS_TPOFF
:
2902 case elfcpp::R_386_TLS_DTPMOD32
:
2903 case elfcpp::R_386_TLS_DTPOFF32
:
2904 case elfcpp::R_386_TLS_TPOFF32
:
2905 case elfcpp::R_386_TLS_DESC
:
2906 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2907 _("unexpected reloc %u in object file"),
2911 // These are initial tls relocs, which are expected when
2913 case elfcpp::R_386_TLS_GD
: // Global-dynamic
2914 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
2915 case elfcpp::R_386_TLS_DESC_CALL
:
2916 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
2917 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
2918 case elfcpp::R_386_TLS_IE
: // Initial-exec
2919 case elfcpp::R_386_TLS_IE_32
:
2920 case elfcpp::R_386_TLS_GOTIE
:
2921 case elfcpp::R_386_TLS_LE
: // Local-exec
2922 case elfcpp::R_386_TLS_LE_32
:
2923 this->relocate_tls(relinfo
, target
, relnum
, rel
, r_type
, gsym
, psymval
,
2924 view
, address
, view_size
);
2927 case elfcpp::R_386_32PLT
:
2928 case elfcpp::R_386_TLS_GD_32
:
2929 case elfcpp::R_386_TLS_GD_PUSH
:
2930 case elfcpp::R_386_TLS_GD_CALL
:
2931 case elfcpp::R_386_TLS_GD_POP
:
2932 case elfcpp::R_386_TLS_LDM_32
:
2933 case elfcpp::R_386_TLS_LDM_PUSH
:
2934 case elfcpp::R_386_TLS_LDM_CALL
:
2935 case elfcpp::R_386_TLS_LDM_POP
:
2936 case elfcpp::R_386_USED_BY_INTEL_200
:
2938 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2939 _("unsupported reloc %u"),
2947 // Perform a TLS relocation.
2950 Target_i386::Relocate::relocate_tls(const Relocate_info
<32, false>* relinfo
,
2951 Target_i386
* target
,
2953 const elfcpp::Rel
<32, false>& rel
,
2954 unsigned int r_type
,
2955 const Sized_symbol
<32>* gsym
,
2956 const Symbol_value
<32>* psymval
,
2957 unsigned char* view
,
2958 elfcpp::Elf_types
<32>::Elf_Addr
,
2959 section_size_type view_size
)
2961 Output_segment
* tls_segment
= relinfo
->layout
->tls_segment();
2963 const Sized_relobj_file
<32, false>* object
= relinfo
->object
;
2965 elfcpp::Elf_types
<32>::Elf_Addr value
= psymval
->value(object
, 0);
2967 const bool is_final
= (gsym
== NULL
2968 ? !parameters
->options().shared()
2969 : gsym
->final_value_is_known());
2970 const tls::Tls_optimization optimized_type
2971 = Target_i386::optimize_tls_reloc(is_final
, r_type
);
2974 case elfcpp::R_386_TLS_GD
: // Global-dynamic
2975 if (optimized_type
== tls::TLSOPT_TO_LE
)
2977 if (tls_segment
== NULL
)
2979 gold_assert(parameters
->errors()->error_count() > 0
2980 || issue_undefined_symbol_error(gsym
));
2983 this->tls_gd_to_le(relinfo
, relnum
, tls_segment
,
2984 rel
, r_type
, value
, view
,
2990 unsigned int got_type
= (optimized_type
== tls::TLSOPT_TO_IE
2991 ? GOT_TYPE_TLS_NOFFSET
2992 : GOT_TYPE_TLS_PAIR
);
2993 unsigned int got_offset
;
2996 gold_assert(gsym
->has_got_offset(got_type
));
2997 got_offset
= gsym
->got_offset(got_type
) - target
->got_size();
3001 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
3002 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
3003 got_offset
= (object
->local_got_offset(r_sym
, got_type
)
3004 - target
->got_size());
3006 if (optimized_type
== tls::TLSOPT_TO_IE
)
3008 this->tls_gd_to_ie(relinfo
, relnum
, tls_segment
, rel
, r_type
,
3009 got_offset
, view
, view_size
);
3012 else if (optimized_type
== tls::TLSOPT_NONE
)
3014 // Relocate the field with the offset of the pair of GOT
3016 Relocate_functions
<32, false>::rel32(view
, got_offset
);
3020 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
3021 _("unsupported reloc %u"),
3025 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
3026 case elfcpp::R_386_TLS_DESC_CALL
:
3027 this->local_dynamic_type_
= LOCAL_DYNAMIC_GNU
;
3028 if (optimized_type
== tls::TLSOPT_TO_LE
)
3030 if (tls_segment
== NULL
)
3032 gold_assert(parameters
->errors()->error_count() > 0
3033 || issue_undefined_symbol_error(gsym
));
3036 this->tls_desc_gd_to_le(relinfo
, relnum
, tls_segment
,
3037 rel
, r_type
, value
, view
,
3043 unsigned int got_type
= (optimized_type
== tls::TLSOPT_TO_IE
3044 ? GOT_TYPE_TLS_NOFFSET
3045 : GOT_TYPE_TLS_DESC
);
3046 unsigned int got_offset
= 0;
3047 if (r_type
== elfcpp::R_386_TLS_GOTDESC
3048 && optimized_type
== tls::TLSOPT_NONE
)
3050 // We created GOT entries in the .got.tlsdesc portion of
3051 // the .got.plt section, but the offset stored in the
3052 // symbol is the offset within .got.tlsdesc.
3053 got_offset
= (target
->got_size()
3054 + target
->got_plt_section()->data_size());
3058 gold_assert(gsym
->has_got_offset(got_type
));
3059 got_offset
+= gsym
->got_offset(got_type
) - target
->got_size();
3063 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
3064 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
3065 got_offset
+= (object
->local_got_offset(r_sym
, got_type
)
3066 - target
->got_size());
3068 if (optimized_type
== tls::TLSOPT_TO_IE
)
3070 if (tls_segment
== NULL
)
3072 gold_assert(parameters
->errors()->error_count() > 0
3073 || issue_undefined_symbol_error(gsym
));
3076 this->tls_desc_gd_to_ie(relinfo
, relnum
, tls_segment
, rel
, r_type
,
3077 got_offset
, view
, view_size
);
3080 else if (optimized_type
== tls::TLSOPT_NONE
)
3082 if (r_type
== elfcpp::R_386_TLS_GOTDESC
)
3084 // Relocate the field with the offset of the pair of GOT
3086 Relocate_functions
<32, false>::rel32(view
, got_offset
);
3091 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
3092 _("unsupported reloc %u"),
3096 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
3097 if (this->local_dynamic_type_
== LOCAL_DYNAMIC_SUN
)
3099 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
3100 _("both SUN and GNU model "
3101 "TLS relocations"));
3104 this->local_dynamic_type_
= LOCAL_DYNAMIC_GNU
;
3105 if (optimized_type
== tls::TLSOPT_TO_LE
)
3107 if (tls_segment
== NULL
)
3109 gold_assert(parameters
->errors()->error_count() > 0
3110 || issue_undefined_symbol_error(gsym
));
3113 this->tls_ld_to_le(relinfo
, relnum
, tls_segment
, rel
, r_type
,
3114 value
, view
, view_size
);
3117 else if (optimized_type
== tls::TLSOPT_NONE
)
3119 // Relocate the field with the offset of the GOT entry for
3120 // the module index.
3121 unsigned int got_offset
;
3122 got_offset
= (target
->got_mod_index_entry(NULL
, NULL
, NULL
)
3123 - target
->got_size());
3124 Relocate_functions
<32, false>::rel32(view
, got_offset
);
3127 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
3128 _("unsupported reloc %u"),
3132 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
3133 if (optimized_type
== tls::TLSOPT_TO_LE
)
3135 // This reloc can appear in debugging sections, in which
3136 // case we must not convert to local-exec. We decide what
3137 // to do based on whether the section is marked as
3138 // containing executable code. That is what the GNU linker
3140 elfcpp::Shdr
<32, false> shdr(relinfo
->data_shdr
);
3141 if ((shdr
.get_sh_flags() & elfcpp::SHF_EXECINSTR
) != 0)
3143 if (tls_segment
== NULL
)
3145 gold_assert(parameters
->errors()->error_count() > 0
3146 || issue_undefined_symbol_error(gsym
));
3149 value
-= tls_segment
->memsz();
3152 Relocate_functions
<32, false>::rel32(view
, value
);
3155 case elfcpp::R_386_TLS_IE
: // Initial-exec
3156 case elfcpp::R_386_TLS_GOTIE
:
3157 case elfcpp::R_386_TLS_IE_32
:
3158 if (optimized_type
== tls::TLSOPT_TO_LE
)
3160 if (tls_segment
== NULL
)
3162 gold_assert(parameters
->errors()->error_count() > 0
3163 || issue_undefined_symbol_error(gsym
));
3166 Target_i386::Relocate::tls_ie_to_le(relinfo
, relnum
, tls_segment
,
3167 rel
, r_type
, value
, view
,
3171 else if (optimized_type
== tls::TLSOPT_NONE
)
3173 // Relocate the field with the offset of the GOT entry for
3174 // the tp-relative offset of the symbol.
3175 unsigned int got_type
= (r_type
== elfcpp::R_386_TLS_IE_32
3176 ? GOT_TYPE_TLS_OFFSET
3177 : GOT_TYPE_TLS_NOFFSET
);
3178 unsigned int got_offset
;
3181 gold_assert(gsym
->has_got_offset(got_type
));
3182 got_offset
= gsym
->got_offset(got_type
);
3186 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
3187 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
3188 got_offset
= object
->local_got_offset(r_sym
, got_type
);
3190 // For the R_386_TLS_IE relocation, we need to apply the
3191 // absolute address of the GOT entry.
3192 if (r_type
== elfcpp::R_386_TLS_IE
)
3193 got_offset
+= target
->got_plt_section()->address();
3194 // All GOT offsets are relative to the end of the GOT.
3195 got_offset
-= target
->got_size();
3196 Relocate_functions
<32, false>::rel32(view
, got_offset
);
3199 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
3200 _("unsupported reloc %u"),
3204 case elfcpp::R_386_TLS_LE
: // Local-exec
3205 // If we're creating a shared library, a dynamic relocation will
3206 // have been created for this location, so do not apply it now.
3207 if (!parameters
->options().shared())
3209 if (tls_segment
== NULL
)
3211 gold_assert(parameters
->errors()->error_count() > 0
3212 || issue_undefined_symbol_error(gsym
));
3215 value
-= tls_segment
->memsz();
3216 Relocate_functions
<32, false>::rel32(view
, value
);
3220 case elfcpp::R_386_TLS_LE_32
:
3221 // If we're creating a shared library, a dynamic relocation will
3222 // have been created for this location, so do not apply it now.
3223 if (!parameters
->options().shared())
3225 if (tls_segment
== NULL
)
3227 gold_assert(parameters
->errors()->error_count() > 0
3228 || issue_undefined_symbol_error(gsym
));
3231 value
= tls_segment
->memsz() - value
;
3232 Relocate_functions
<32, false>::rel32(view
, value
);
3238 // Do a relocation in which we convert a TLS General-Dynamic to a
3242 Target_i386::Relocate::tls_gd_to_le(const Relocate_info
<32, false>* relinfo
,
3244 Output_segment
* tls_segment
,
3245 const elfcpp::Rel
<32, false>& rel
,
3247 elfcpp::Elf_types
<32>::Elf_Addr value
,
3248 unsigned char* view
,
3249 section_size_type view_size
)
3251 // leal foo(,%reg,1),%eax; call ___tls_get_addr
3252 // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
3253 // leal foo(%reg),%eax; call ___tls_get_addr
3254 // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
3256 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
3257 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 9);
3259 unsigned char op1
= view
[-1];
3260 unsigned char op2
= view
[-2];
3262 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3263 op2
== 0x8d || op2
== 0x04);
3264 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[4] == 0xe8);
3270 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -3);
3271 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[-3] == 0x8d);
3272 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3273 ((op1
& 0xc7) == 0x05 && op1
!= (4 << 3)));
3274 memcpy(view
- 3, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
3278 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3279 (op1
& 0xf8) == 0x80 && (op1
& 7) != 4);
3280 if (rel
.get_r_offset() + 9 < view_size
3283 // There is a trailing nop. Use the size byte subl.
3284 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
3289 // Use the five byte subl.
3290 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
3294 value
= tls_segment
->memsz() - value
;
3295 Relocate_functions
<32, false>::rel32(view
+ roff
, value
);
3297 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3299 this->skip_call_tls_get_addr_
= true;
3302 // Do a relocation in which we convert a TLS General-Dynamic to an
3306 Target_i386::Relocate::tls_gd_to_ie(const Relocate_info
<32, false>* relinfo
,
3309 const elfcpp::Rel
<32, false>& rel
,
3311 elfcpp::Elf_types
<32>::Elf_Addr value
,
3312 unsigned char* view
,
3313 section_size_type view_size
)
3315 // leal foo(,%ebx,1),%eax; call ___tls_get_addr
3316 // ==> movl %gs:0,%eax; addl foo@gotntpoff(%ebx),%eax
3317 // leal foo(%ebx),%eax; call ___tls_get_addr; nop
3318 // ==> movl %gs:0,%eax; addl foo@gotntpoff(%ebx),%eax
3320 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
3321 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 9);
3323 unsigned char op1
= view
[-1];
3324 unsigned char op2
= view
[-2];
3326 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3327 op2
== 0x8d || op2
== 0x04);
3328 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[4] == 0xe8);
3334 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -3);
3335 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[-3] == 0x8d);
3336 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3337 ((op1
& 0xc7) == 0x05 && op1
!= (4 << 3)));
3342 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 10);
3343 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3344 (op1
& 0xf8) == 0x80 && (op1
& 7) != 4);
3345 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[9] == 0x90);
3349 memcpy(view
+ roff
- 8, "\x65\xa1\0\0\0\0\x03\x83\0\0\0", 12);
3350 Relocate_functions
<32, false>::rel32(view
+ roff
, value
);
3352 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3354 this->skip_call_tls_get_addr_
= true;
3357 // Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL
3358 // General-Dynamic to a Local-Exec.
3361 Target_i386::Relocate::tls_desc_gd_to_le(
3362 const Relocate_info
<32, false>* relinfo
,
3364 Output_segment
* tls_segment
,
3365 const elfcpp::Rel
<32, false>& rel
,
3366 unsigned int r_type
,
3367 elfcpp::Elf_types
<32>::Elf_Addr value
,
3368 unsigned char* view
,
3369 section_size_type view_size
)
3371 if (r_type
== elfcpp::R_386_TLS_GOTDESC
)
3373 // leal foo@TLSDESC(%ebx), %eax
3374 // ==> leal foo@NTPOFF, %eax
3375 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
3376 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
3377 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3378 view
[-2] == 0x8d && view
[-1] == 0x83);
3380 value
-= tls_segment
->memsz();
3381 Relocate_functions
<32, false>::rel32(view
, value
);
3385 // call *foo@TLSCALL(%eax)
3387 gold_assert(r_type
== elfcpp::R_386_TLS_DESC_CALL
);
3388 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 2);
3389 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3390 view
[0] == 0xff && view
[1] == 0x10);
3396 // Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL
3397 // General-Dynamic to an Initial-Exec.
3400 Target_i386::Relocate::tls_desc_gd_to_ie(
3401 const Relocate_info
<32, false>* relinfo
,
3404 const elfcpp::Rel
<32, false>& rel
,
3405 unsigned int r_type
,
3406 elfcpp::Elf_types
<32>::Elf_Addr value
,
3407 unsigned char* view
,
3408 section_size_type view_size
)
3410 if (r_type
== elfcpp::R_386_TLS_GOTDESC
)
3412 // leal foo@TLSDESC(%ebx), %eax
3413 // ==> movl foo@GOTNTPOFF(%ebx), %eax
3414 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
3415 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
3416 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3417 view
[-2] == 0x8d && view
[-1] == 0x83);
3419 Relocate_functions
<32, false>::rel32(view
, value
);
3423 // call *foo@TLSCALL(%eax)
3425 gold_assert(r_type
== elfcpp::R_386_TLS_DESC_CALL
);
3426 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 2);
3427 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3428 view
[0] == 0xff && view
[1] == 0x10);
3434 // Do a relocation in which we convert a TLS Local-Dynamic to a
3438 Target_i386::Relocate::tls_ld_to_le(const Relocate_info
<32, false>* relinfo
,
3441 const elfcpp::Rel
<32, false>& rel
,
3443 elfcpp::Elf_types
<32>::Elf_Addr
,
3444 unsigned char* view
,
3445 section_size_type view_size
)
3447 // leal foo(%reg), %eax; call ___tls_get_addr
3448 // ==> movl %gs:0,%eax; nop; leal 0(%esi,1),%esi
3450 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
3451 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 9);
3453 // FIXME: Does this test really always pass?
3454 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3455 view
[-2] == 0x8d && view
[-1] == 0x83);
3457 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[4] == 0xe8);
3459 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x90\x8d\x74\x26\0", 11);
3461 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3463 this->skip_call_tls_get_addr_
= true;
3466 // Do a relocation in which we convert a TLS Initial-Exec to a
3470 Target_i386::Relocate::tls_ie_to_le(const Relocate_info
<32, false>* relinfo
,
3472 Output_segment
* tls_segment
,
3473 const elfcpp::Rel
<32, false>& rel
,
3474 unsigned int r_type
,
3475 elfcpp::Elf_types
<32>::Elf_Addr value
,
3476 unsigned char* view
,
3477 section_size_type view_size
)
3479 // We have to actually change the instructions, which means that we
3480 // need to examine the opcodes to figure out which instruction we
3482 if (r_type
== elfcpp::R_386_TLS_IE
)
3484 // movl %gs:XX,%eax ==> movl $YY,%eax
3485 // movl %gs:XX,%reg ==> movl $YY,%reg
3486 // addl %gs:XX,%reg ==> addl $YY,%reg
3487 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -1);
3488 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
3490 unsigned char op1
= view
[-1];
3493 // movl XX,%eax ==> movl $YY,%eax
3498 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
3500 unsigned char op2
= view
[-2];
3503 // movl XX,%reg ==> movl $YY,%reg
3504 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3505 (op1
& 0xc7) == 0x05);
3507 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
3509 else if (op2
== 0x03)
3511 // addl XX,%reg ==> addl $YY,%reg
3512 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3513 (op1
& 0xc7) == 0x05);
3515 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
3518 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), 0);
3523 // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2
3524 // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2
3525 // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2
3526 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
3527 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
3529 unsigned char op1
= view
[-1];
3530 unsigned char op2
= view
[-2];
3531 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3532 (op1
& 0xc0) == 0x80 && (op1
& 7) != 4);
3535 // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2
3537 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
3539 else if (op2
== 0x2b)
3541 // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2
3543 view
[-1] = 0xe8 | ((op1
>> 3) & 7);
3545 else if (op2
== 0x03)
3547 // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2
3549 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
3552 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), 0);
3555 value
= tls_segment
->memsz() - value
;
3556 if (r_type
== elfcpp::R_386_TLS_IE
|| r_type
== elfcpp::R_386_TLS_GOTIE
)
3559 Relocate_functions
<32, false>::rel32(view
, value
);
3562 // Relocate section data.
3565 Target_i386::relocate_section(const Relocate_info
<32, false>* relinfo
,
3566 unsigned int sh_type
,
3567 const unsigned char* prelocs
,
3569 Output_section
* output_section
,
3570 bool needs_special_offset_handling
,
3571 unsigned char* view
,
3572 elfcpp::Elf_types
<32>::Elf_Addr address
,
3573 section_size_type view_size
,
3574 const Reloc_symbol_changes
* reloc_symbol_changes
)
3576 gold_assert(sh_type
== elfcpp::SHT_REL
);
3578 gold::relocate_section
<32, false, Target_i386
, elfcpp::SHT_REL
,
3579 Target_i386::Relocate
, gold::Default_comdat_behavior
>(
3585 needs_special_offset_handling
,
3589 reloc_symbol_changes
);
3592 // Return the size of a relocation while scanning during a relocatable
3596 Target_i386::Relocatable_size_for_reloc::get_size_for_reloc(
3597 unsigned int r_type
,
3602 case elfcpp::R_386_NONE
:
3603 case elfcpp::R_386_GNU_VTINHERIT
:
3604 case elfcpp::R_386_GNU_VTENTRY
:
3605 case elfcpp::R_386_TLS_GD
: // Global-dynamic
3606 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
3607 case elfcpp::R_386_TLS_DESC_CALL
:
3608 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
3609 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
3610 case elfcpp::R_386_TLS_IE
: // Initial-exec
3611 case elfcpp::R_386_TLS_IE_32
:
3612 case elfcpp::R_386_TLS_GOTIE
:
3613 case elfcpp::R_386_TLS_LE
: // Local-exec
3614 case elfcpp::R_386_TLS_LE_32
:
3617 case elfcpp::R_386_32
:
3618 case elfcpp::R_386_PC32
:
3619 case elfcpp::R_386_GOT32
:
3620 case elfcpp::R_386_PLT32
:
3621 case elfcpp::R_386_GOTOFF
:
3622 case elfcpp::R_386_GOTPC
:
3625 case elfcpp::R_386_16
:
3626 case elfcpp::R_386_PC16
:
3629 case elfcpp::R_386_8
:
3630 case elfcpp::R_386_PC8
:
3633 // These are relocations which should only be seen by the
3634 // dynamic linker, and should never be seen here.
3635 case elfcpp::R_386_COPY
:
3636 case elfcpp::R_386_GLOB_DAT
:
3637 case elfcpp::R_386_JUMP_SLOT
:
3638 case elfcpp::R_386_RELATIVE
:
3639 case elfcpp::R_386_IRELATIVE
:
3640 case elfcpp::R_386_TLS_TPOFF
:
3641 case elfcpp::R_386_TLS_DTPMOD32
:
3642 case elfcpp::R_386_TLS_DTPOFF32
:
3643 case elfcpp::R_386_TLS_TPOFF32
:
3644 case elfcpp::R_386_TLS_DESC
:
3645 object
->error(_("unexpected reloc %u in object file"), r_type
);
3648 case elfcpp::R_386_32PLT
:
3649 case elfcpp::R_386_TLS_GD_32
:
3650 case elfcpp::R_386_TLS_GD_PUSH
:
3651 case elfcpp::R_386_TLS_GD_CALL
:
3652 case elfcpp::R_386_TLS_GD_POP
:
3653 case elfcpp::R_386_TLS_LDM_32
:
3654 case elfcpp::R_386_TLS_LDM_PUSH
:
3655 case elfcpp::R_386_TLS_LDM_CALL
:
3656 case elfcpp::R_386_TLS_LDM_POP
:
3657 case elfcpp::R_386_USED_BY_INTEL_200
:
3659 object
->error(_("unsupported reloc %u in object file"), r_type
);
3664 // Scan the relocs during a relocatable link.
3667 Target_i386::scan_relocatable_relocs(Symbol_table
* symtab
,
3669 Sized_relobj_file
<32, false>* object
,
3670 unsigned int data_shndx
,
3671 unsigned int sh_type
,
3672 const unsigned char* prelocs
,
3674 Output_section
* output_section
,
3675 bool needs_special_offset_handling
,
3676 size_t local_symbol_count
,
3677 const unsigned char* plocal_symbols
,
3678 Relocatable_relocs
* rr
)
3680 gold_assert(sh_type
== elfcpp::SHT_REL
);
3682 typedef gold::Default_scan_relocatable_relocs
<elfcpp::SHT_REL
,
3683 Relocatable_size_for_reloc
> Scan_relocatable_relocs
;
3685 gold::scan_relocatable_relocs
<32, false, elfcpp::SHT_REL
,
3686 Scan_relocatable_relocs
>(
3694 needs_special_offset_handling
,
3700 // Emit relocations for a section.
3703 Target_i386::relocate_relocs(
3704 const Relocate_info
<32, false>* relinfo
,
3705 unsigned int sh_type
,
3706 const unsigned char* prelocs
,
3708 Output_section
* output_section
,
3709 elfcpp::Elf_types
<32>::Elf_Off offset_in_output_section
,
3710 const Relocatable_relocs
* rr
,
3711 unsigned char* view
,
3712 elfcpp::Elf_types
<32>::Elf_Addr view_address
,
3713 section_size_type view_size
,
3714 unsigned char* reloc_view
,
3715 section_size_type reloc_view_size
)
3717 gold_assert(sh_type
== elfcpp::SHT_REL
);
3719 gold::relocate_relocs
<32, false, elfcpp::SHT_REL
>(
3724 offset_in_output_section
,
3733 // Return the value to use for a dynamic which requires special
3734 // treatment. This is how we support equality comparisons of function
3735 // pointers across shared library boundaries, as described in the
3736 // processor specific ABI supplement.
3739 Target_i386::do_dynsym_value(const Symbol
* gsym
) const
3741 gold_assert(gsym
->is_from_dynobj() && gsym
->has_plt_offset());
3742 return this->plt_address_for_global(gsym
);
3745 // Return a string used to fill a code section with nops to take up
3746 // the specified length.
3749 Target_i386::do_code_fill(section_size_type length
) const
3753 // Build a jmp instruction to skip over the bytes.
3754 unsigned char jmp
[5];
3756 elfcpp::Swap_unaligned
<32, false>::writeval(jmp
+ 1, length
- 5);
3757 return (std::string(reinterpret_cast<char*>(&jmp
[0]), 5)
3758 + std::string(length
- 5, static_cast<char>(0x90)));
3761 // Nop sequences of various lengths.
3762 const char nop1
[1] = { '\x90' }; // nop
3763 const char nop2
[2] = { '\x66', '\x90' }; // xchg %ax %ax
3764 const char nop3
[3] = { '\x8d', '\x76', '\x00' }; // leal 0(%esi),%esi
3765 const char nop4
[4] = { '\x8d', '\x74', '\x26', // leal 0(%esi,1),%esi
3767 const char nop5
[5] = { '\x90', '\x8d', '\x74', // nop
3768 '\x26', '\x00' }; // leal 0(%esi,1),%esi
3769 const char nop6
[6] = { '\x8d', '\xb6', '\x00', // leal 0L(%esi),%esi
3770 '\x00', '\x00', '\x00' };
3771 const char nop7
[7] = { '\x8d', '\xb4', '\x26', // leal 0L(%esi,1),%esi
3772 '\x00', '\x00', '\x00',
3774 const char nop8
[8] = { '\x90', '\x8d', '\xb4', // nop
3775 '\x26', '\x00', '\x00', // leal 0L(%esi,1),%esi
3777 const char nop9
[9] = { '\x89', '\xf6', '\x8d', // movl %esi,%esi
3778 '\xbc', '\x27', '\x00', // leal 0L(%edi,1),%edi
3779 '\x00', '\x00', '\x00' };
3780 const char nop10
[10] = { '\x8d', '\x76', '\x00', // leal 0(%esi),%esi
3781 '\x8d', '\xbc', '\x27', // leal 0L(%edi,1),%edi
3782 '\x00', '\x00', '\x00',
3784 const char nop11
[11] = { '\x8d', '\x74', '\x26', // leal 0(%esi,1),%esi
3785 '\x00', '\x8d', '\xbc', // leal 0L(%edi,1),%edi
3786 '\x27', '\x00', '\x00',
3788 const char nop12
[12] = { '\x8d', '\xb6', '\x00', // leal 0L(%esi),%esi
3789 '\x00', '\x00', '\x00', // leal 0L(%edi),%edi
3790 '\x8d', '\xbf', '\x00',
3791 '\x00', '\x00', '\x00' };
3792 const char nop13
[13] = { '\x8d', '\xb6', '\x00', // leal 0L(%esi),%esi
3793 '\x00', '\x00', '\x00', // leal 0L(%edi,1),%edi
3794 '\x8d', '\xbc', '\x27',
3795 '\x00', '\x00', '\x00',
3797 const char nop14
[14] = { '\x8d', '\xb4', '\x26', // leal 0L(%esi,1),%esi
3798 '\x00', '\x00', '\x00', // leal 0L(%edi,1),%edi
3799 '\x00', '\x8d', '\xbc',
3800 '\x27', '\x00', '\x00',
3802 const char nop15
[15] = { '\xeb', '\x0d', '\x90', // jmp .+15
3803 '\x90', '\x90', '\x90', // nop,nop,nop,...
3804 '\x90', '\x90', '\x90',
3805 '\x90', '\x90', '\x90',
3806 '\x90', '\x90', '\x90' };
3808 const char* nops
[16] = {
3810 nop1
, nop2
, nop3
, nop4
, nop5
, nop6
, nop7
,
3811 nop8
, nop9
, nop10
, nop11
, nop12
, nop13
, nop14
, nop15
3814 return std::string(nops
[length
], length
);
3817 // Return the value to use for the base of a DW_EH_PE_datarel offset
3818 // in an FDE. Solaris and SVR4 use DW_EH_PE_datarel because their
3819 // assembler can not write out the difference between two labels in
3820 // different sections, so instead of using a pc-relative value they
3821 // use an offset from the GOT.
3824 Target_i386::do_ehframe_datarel_base() const
3826 gold_assert(this->global_offset_table_
!= NULL
);
3827 Symbol
* sym
= this->global_offset_table_
;
3828 Sized_symbol
<32>* ssym
= static_cast<Sized_symbol
<32>*>(sym
);
3829 return ssym
->value();
3832 // Return whether SYM should be treated as a call to a non-split
3833 // function. We don't want that to be true of a call to a
3834 // get_pc_thunk function.
3837 Target_i386::do_is_call_to_non_split(const Symbol
* sym
, unsigned int) const
3839 return (sym
->type() == elfcpp::STT_FUNC
3840 && !is_prefix_of("__i686.get_pc_thunk.", sym
->name()));
3843 // FNOFFSET in section SHNDX in OBJECT is the start of a function
3844 // compiled with -fsplit-stack. The function calls non-split-stack
3845 // code. We have to change the function so that it always ensures
3846 // that it has enough stack space to run some random function.
3849 Target_i386::do_calls_non_split(Relobj
* object
, unsigned int shndx
,
3850 section_offset_type fnoffset
,
3851 section_size_type fnsize
,
3852 unsigned char* view
,
3853 section_size_type view_size
,
3855 std::string
* to
) const
3857 // The function starts with a comparison of the stack pointer and a
3858 // field in the TCB. This is followed by a jump.
3861 if (this->match_view(view
, view_size
, fnoffset
, "\x65\x3b\x25", 3)
3864 // We will call __morestack if the carry flag is set after this
3865 // comparison. We turn the comparison into an stc instruction
3867 view
[fnoffset
] = '\xf9';
3868 this->set_view_to_nop(view
, view_size
, fnoffset
+ 1, 6);
3870 // lea NN(%esp),%ecx
3871 // lea NN(%esp),%edx
3872 else if ((this->match_view(view
, view_size
, fnoffset
, "\x8d\x8c\x24", 3)
3873 || this->match_view(view
, view_size
, fnoffset
, "\x8d\x94\x24", 3))
3876 // This is loading an offset from the stack pointer for a
3877 // comparison. The offset is negative, so we decrease the
3878 // offset by the amount of space we need for the stack. This
3879 // means we will avoid calling __morestack if there happens to
3880 // be plenty of space on the stack already.
3881 unsigned char* pval
= view
+ fnoffset
+ 3;
3882 uint32_t val
= elfcpp::Swap_unaligned
<32, false>::readval(pval
);
3883 val
-= parameters
->options().split_stack_adjust_size();
3884 elfcpp::Swap_unaligned
<32, false>::writeval(pval
, val
);
3888 if (!object
->has_no_split_stack())
3889 object
->error(_("failed to match split-stack sequence at "
3890 "section %u offset %0zx"),
3891 shndx
, static_cast<size_t>(fnoffset
));
3895 // We have to change the function so that it calls
3896 // __morestack_non_split instead of __morestack. The former will
3897 // allocate additional stack space.
3898 *from
= "__morestack";
3899 *to
= "__morestack_non_split";
3902 // The selector for i386 object files. Note this is never instantiated
3903 // directly. It's only used in Target_selector_i386_nacl, below.
3905 class Target_selector_i386
: public Target_selector_freebsd
3908 Target_selector_i386()
3909 : Target_selector_freebsd(elfcpp::EM_386
, 32, false,
3910 "elf32-i386", "elf32-i386-freebsd",
3915 do_instantiate_target()
3916 { return new Target_i386(); }
3919 // NaCl variant. It uses different PLT contents.
3921 class Output_data_plt_i386_nacl
: public Output_data_plt_i386
3924 Output_data_plt_i386_nacl(Layout
* layout
,
3925 Output_data_got_plt_i386
* got_plt
,
3926 Output_data_space
* got_irelative
)
3927 : Output_data_plt_i386(layout
, plt_entry_size
, got_plt
, got_irelative
)
3931 virtual unsigned int
3932 do_get_plt_entry_size() const
3933 { return plt_entry_size
; }
3936 do_add_eh_frame(Layout
* layout
)
3938 layout
->add_eh_frame_for_plt(this, plt_eh_frame_cie
, plt_eh_frame_cie_size
,
3939 plt_eh_frame_fde
, plt_eh_frame_fde_size
);
3942 // The size of an entry in the PLT.
3943 static const int plt_entry_size
= 64;
3945 // The .eh_frame unwind information for the PLT.
3946 static const int plt_eh_frame_fde_size
= 32;
3947 static const unsigned char plt_eh_frame_fde
[plt_eh_frame_fde_size
];
3950 class Output_data_plt_i386_nacl_exec
: public Output_data_plt_i386_nacl
3953 Output_data_plt_i386_nacl_exec(Layout
* layout
,
3954 Output_data_got_plt_i386
* got_plt
,
3955 Output_data_space
* got_irelative
)
3956 : Output_data_plt_i386_nacl(layout
, got_plt
, got_irelative
)
3961 do_fill_first_plt_entry(unsigned char* pov
,
3962 elfcpp::Elf_types
<32>::Elf_Addr got_address
);
3964 virtual unsigned int
3965 do_fill_plt_entry(unsigned char* pov
,
3966 elfcpp::Elf_types
<32>::Elf_Addr got_address
,
3967 unsigned int got_offset
,
3968 unsigned int plt_offset
,
3969 unsigned int plt_rel_offset
);
3972 // The first entry in the PLT for an executable.
3973 static const unsigned char first_plt_entry
[plt_entry_size
];
3975 // Other entries in the PLT for an executable.
3976 static const unsigned char plt_entry
[plt_entry_size
];
3979 class Output_data_plt_i386_nacl_dyn
: public Output_data_plt_i386_nacl
3982 Output_data_plt_i386_nacl_dyn(Layout
* layout
,
3983 Output_data_got_plt_i386
* got_plt
,
3984 Output_data_space
* got_irelative
)
3985 : Output_data_plt_i386_nacl(layout
, got_plt
, got_irelative
)
3990 do_fill_first_plt_entry(unsigned char* pov
, elfcpp::Elf_types
<32>::Elf_Addr
);
3992 virtual unsigned int
3993 do_fill_plt_entry(unsigned char* pov
,
3994 elfcpp::Elf_types
<32>::Elf_Addr
,
3995 unsigned int got_offset
,
3996 unsigned int plt_offset
,
3997 unsigned int plt_rel_offset
);
4000 // The first entry in the PLT for a shared object.
4001 static const unsigned char first_plt_entry
[plt_entry_size
];
4003 // Other entries in the PLT for a shared object.
4004 static const unsigned char plt_entry
[plt_entry_size
];
4007 class Target_i386_nacl
: public Target_i386
4011 : Target_i386(&i386_nacl_info
)
4015 virtual Output_data_plt_i386
*
4016 do_make_data_plt(Layout
* layout
,
4017 Output_data_got_plt_i386
* got_plt
,
4018 Output_data_space
* got_irelative
,
4022 return new Output_data_plt_i386_nacl_dyn(layout
, got_plt
, got_irelative
);
4024 return new Output_data_plt_i386_nacl_exec(layout
, got_plt
, got_irelative
);
4028 do_code_fill(section_size_type length
) const;
4031 static const Target::Target_info i386_nacl_info
;
4034 const Target::Target_info
Target_i386_nacl::i386_nacl_info
=
4037 false, // is_big_endian
4038 elfcpp::EM_386
, // machine_code
4039 false, // has_make_symbol
4040 false, // has_resolve
4041 true, // has_code_fill
4042 true, // is_default_stack_executable
4043 true, // can_icf_inline_merge_sections
4045 "/lib/ld-nacl-x86-32.so.1", // dynamic_linker
4046 0x20000, // default_text_segment_address
4047 0x10000, // abi_pagesize (overridable by -z max-page-size)
4048 0x10000, // common_pagesize (overridable by -z common-page-size)
4049 true, // isolate_execinstr
4050 0x10000000, // rosegment_gap
4051 elfcpp::SHN_UNDEF
, // small_common_shndx
4052 elfcpp::SHN_UNDEF
, // large_common_shndx
4053 0, // small_common_section_flags
4054 0, // large_common_section_flags
4055 NULL
, // attributes_section
4056 NULL
, // attributes_vendor
4057 "_start" // entry_symbol_name
4060 #define NACLMASK 0xe0 // 32-byte alignment mask
4063 Output_data_plt_i386_nacl_exec::first_plt_entry
[plt_entry_size
] =
4065 0xff, 0x35, // pushl contents of memory address
4066 0, 0, 0, 0, // replaced with address of .got + 4
4067 0x8b, 0x0d, // movl contents of address, %ecx
4068 0, 0, 0, 0, // replaced with address of .got + 8
4069 0x83, 0xe1, NACLMASK
, // andl $NACLMASK, %ecx
4070 0xff, 0xe1, // jmp *%ecx
4071 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4072 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4073 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4074 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4075 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4076 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4077 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4078 0x90, 0x90, 0x90, 0x90, 0x90
4082 Output_data_plt_i386_nacl_exec::do_fill_first_plt_entry(
4084 elfcpp::Elf_types
<32>::Elf_Addr got_address
)
4086 memcpy(pov
, first_plt_entry
, plt_entry_size
);
4087 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2, got_address
+ 4);
4088 elfcpp::Swap
<32, false>::writeval(pov
+ 8, got_address
+ 8);
4091 // The first entry in the PLT for a shared object.
4094 Output_data_plt_i386_nacl_dyn::first_plt_entry
[plt_entry_size
] =
4096 0xff, 0xb3, 4, 0, 0, 0, // pushl 4(%ebx)
4097 0x8b, 0x4b, 0x08, // mov 0x8(%ebx), %ecx
4098 0x83, 0xe1, NACLMASK
, // andl $NACLMASK, %ecx
4099 0xff, 0xe1, // jmp *%ecx
4100 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4101 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4102 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4103 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4104 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4105 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4106 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4107 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4108 0x90, 0x90, 0x90, 0x90, 0x90, // nops
4109 0x90, 0x90, 0x90, 0x90, 0x90 // nops
4113 Output_data_plt_i386_nacl_dyn::do_fill_first_plt_entry(
4115 elfcpp::Elf_types
<32>::Elf_Addr
)
4117 memcpy(pov
, first_plt_entry
, plt_entry_size
);
4120 // Subsequent entries in the PLT for an executable.
4123 Output_data_plt_i386_nacl_exec::plt_entry
[plt_entry_size
] =
4125 0x8b, 0x0d, // movl contents of address, %ecx */
4126 0, 0, 0, 0, // replaced with address of symbol in .got
4127 0x83, 0xe1, NACLMASK
, // andl $NACLMASK, %ecx
4128 0xff, 0xe1, // jmp *%ecx
4130 // Pad to the next 32-byte boundary with nop instructions.
4132 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4133 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4135 // Lazy GOT entries point here (32-byte aligned).
4136 0x68, // pushl immediate
4137 0, 0, 0, 0, // replaced with offset into relocation table
4138 0xe9, // jmp relative
4139 0, 0, 0, 0, // replaced with offset to start of .plt
4141 // Pad to the next 32-byte boundary with nop instructions.
4142 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4143 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4148 Output_data_plt_i386_nacl_exec::do_fill_plt_entry(
4150 elfcpp::Elf_types
<32>::Elf_Addr got_address
,
4151 unsigned int got_offset
,
4152 unsigned int plt_offset
,
4153 unsigned int plt_rel_offset
)
4155 memcpy(pov
, plt_entry
, plt_entry_size
);
4156 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
4157 got_address
+ got_offset
);
4158 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 33, plt_rel_offset
);
4159 elfcpp::Swap
<32, false>::writeval(pov
+ 38, - (plt_offset
+ 38 + 4));
4163 // Subsequent entries in the PLT for a shared object.
4166 Output_data_plt_i386_nacl_dyn::plt_entry
[plt_entry_size
] =
4168 0x8b, 0x8b, // movl offset(%ebx), %ecx
4169 0, 0, 0, 0, // replaced with offset of symbol in .got
4170 0x83, 0xe1, 0xe0, // andl $NACLMASK, %ecx
4171 0xff, 0xe1, // jmp *%ecx
4173 // Pad to the next 32-byte boundary with nop instructions.
4175 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4176 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4178 // Lazy GOT entries point here (32-byte aligned).
4179 0x68, // pushl immediate
4180 0, 0, 0, 0, // replaced with offset into relocation table.
4181 0xe9, // jmp relative
4182 0, 0, 0, 0, // replaced with offset to start of .plt.
4184 // Pad to the next 32-byte boundary with nop instructions.
4185 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4186 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90,
4191 Output_data_plt_i386_nacl_dyn::do_fill_plt_entry(
4193 elfcpp::Elf_types
<32>::Elf_Addr
,
4194 unsigned int got_offset
,
4195 unsigned int plt_offset
,
4196 unsigned int plt_rel_offset
)
4198 memcpy(pov
, plt_entry
, plt_entry_size
);
4199 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2, got_offset
);
4200 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 33, plt_rel_offset
);
4201 elfcpp::Swap
<32, false>::writeval(pov
+ 38, - (plt_offset
+ 38 + 4));
4206 Output_data_plt_i386_nacl::plt_eh_frame_fde
[plt_eh_frame_fde_size
] =
4208 0, 0, 0, 0, // Replaced with offset to .plt.
4209 0, 0, 0, 0, // Replaced with size of .plt.
4210 0, // Augmentation size.
4211 elfcpp::DW_CFA_def_cfa_offset
, 8, // DW_CFA_def_cfa_offset: 8.
4212 elfcpp::DW_CFA_advance_loc
+ 6, // Advance 6 to __PLT__ + 6.
4213 elfcpp::DW_CFA_def_cfa_offset
, 12, // DW_CFA_def_cfa_offset: 12.
4214 elfcpp::DW_CFA_advance_loc
+ 58, // Advance 58 to __PLT__ + 64.
4215 elfcpp::DW_CFA_def_cfa_expression
, // DW_CFA_def_cfa_expression.
4216 13, // Block length.
4217 elfcpp::DW_OP_breg4
, 4, // Push %esp + 4.
4218 elfcpp::DW_OP_breg8
, 0, // Push %eip.
4219 elfcpp::DW_OP_const1u
, 63, // Push 0x3f.
4220 elfcpp::DW_OP_and
, // & (%eip & 0x3f).
4221 elfcpp::DW_OP_const1u
, 37, // Push 0x25.
4222 elfcpp::DW_OP_ge
, // >= ((%eip & 0x3f) >= 0x25)
4223 elfcpp::DW_OP_lit2
, // Push 2.
4224 elfcpp::DW_OP_shl
, // << (((%eip & 0x3f) >= 0x25) << 2)
4225 elfcpp::DW_OP_plus
, // + ((((%eip&0x3f)>=0x25)<<2)+%esp+4
4226 elfcpp::DW_CFA_nop
, // Align to 32 bytes.
4230 // Return a string used to fill a code section with nops.
4231 // For NaCl, long NOPs are only valid if they do not cross
4232 // bundle alignment boundaries, so keep it simple with one-byte NOPs.
4234 Target_i386_nacl::do_code_fill(section_size_type length
) const
4236 return std::string(length
, static_cast<char>(0x90));
4239 // The selector for i386-nacl object files.
4241 class Target_selector_i386_nacl
4242 : public Target_selector_nacl
<Target_selector_i386
, Target_i386_nacl
>
4245 Target_selector_i386_nacl()
4246 : Target_selector_nacl
<Target_selector_i386
,
4247 Target_i386_nacl
>("x86-32",
4253 Target_selector_i386_nacl target_selector_i386
;
4255 } // End anonymous namespace.