1 // i386.cc -- i386 target support for gold.
3 // Copyright 2006, 2007, 2008, 2009, 2010, 2011 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"
49 // A class to handle the PLT data.
51 class Output_data_plt_i386
: public Output_section_data
54 typedef Output_data_reloc
<elfcpp::SHT_REL
, true, 32, false> Reloc_section
;
56 Output_data_plt_i386(Layout
*, Output_data_space
*, Output_data_space
*);
58 // Add an entry to the PLT.
60 add_entry(Symbol_table
*, Layout
*, Symbol
* gsym
);
62 // Add an entry to the PLT for a local STT_GNU_IFUNC symbol.
64 add_local_ifunc_entry(Symbol_table
*, Layout
*,
65 Sized_relobj_file
<32, false>* relobj
,
66 unsigned int local_sym_index
);
68 // Return the .rel.plt section data.
71 { return this->rel_
; }
73 // Return where the TLS_DESC relocations should go.
75 rel_tls_desc(Layout
*);
77 // Return where the IRELATIVE relocations should go.
79 rel_irelative(Symbol_table
*, Layout
*);
81 // Return whether we created a section for IRELATIVE relocations.
83 has_irelative_section() const
84 { return this->irelative_rel_
!= NULL
; }
86 // Return the number of PLT entries.
89 { return this->count_
+ this->irelative_count_
; }
91 // Return the offset of the first non-reserved PLT entry.
93 first_plt_entry_offset()
94 { return plt_entry_size
; }
96 // Return the size of a PLT entry.
99 { return plt_entry_size
; }
101 // Return the PLT address to use for a global symbol.
103 address_for_global(const Symbol
*);
105 // Return the PLT address to use for a local symbol.
107 address_for_local(const Relobj
*, unsigned int symndx
);
111 do_adjust_output_section(Output_section
* os
);
113 // Write to a map file.
115 do_print_to_mapfile(Mapfile
* mapfile
) const
116 { mapfile
->print_output_data(this, _("** PLT")); }
119 // The size of an entry in the PLT.
120 static const int plt_entry_size
= 16;
122 // The first entry in the PLT for an executable.
123 static const unsigned char exec_first_plt_entry
[plt_entry_size
];
125 // The first entry in the PLT for a shared object.
126 static const unsigned char dyn_first_plt_entry
[plt_entry_size
];
128 // Other entries in the PLT for an executable.
129 static const unsigned char exec_plt_entry
[plt_entry_size
];
131 // Other entries in the PLT for a shared object.
132 static const unsigned char dyn_plt_entry
[plt_entry_size
];
134 // The .eh_frame unwind information for the PLT.
135 static const int plt_eh_frame_cie_size
= 16;
136 static const int plt_eh_frame_fde_size
= 32;
137 static const unsigned char plt_eh_frame_cie
[plt_eh_frame_cie_size
];
138 static const unsigned char plt_eh_frame_fde
[plt_eh_frame_fde_size
];
140 // Set the final size.
142 set_final_data_size()
144 this->set_data_size((this->count_
+ this->irelative_count_
+ 1)
148 // Write out the PLT data.
150 do_write(Output_file
*);
152 // We keep a list of global STT_GNU_IFUNC symbols, each with its
153 // offset in the GOT.
157 unsigned int got_offset
;
160 // We keep a list of local STT_GNU_IFUNC symbols, each with its
161 // offset in the GOT.
164 Sized_relobj_file
<32, false>* object
;
165 unsigned int local_sym_index
;
166 unsigned int got_offset
;
169 // A pointer to the Layout class, so that we can find the .dynamic
170 // section when we write out the GOT PLT section.
172 // The reloc section.
174 // The TLS_DESC relocations, if necessary. These must follow the
175 // regular PLT relocs.
176 Reloc_section
* tls_desc_rel_
;
177 // The IRELATIVE relocations, if necessary. These must follow the
178 // regular relocatoins and the TLS_DESC relocations.
179 Reloc_section
* irelative_rel_
;
180 // The .got.plt section.
181 Output_data_space
* got_plt_
;
182 // The part of the .got.plt section used for IRELATIVE relocs.
183 Output_data_space
* got_irelative_
;
184 // The number of PLT entries.
186 // Number of PLT entries with R_386_IRELATIVE relocs. These follow
187 // the regular PLT entries.
188 unsigned int irelative_count_
;
189 // Global STT_GNU_IFUNC symbols.
190 std::vector
<Global_ifunc
> global_ifuncs_
;
191 // Local STT_GNU_IFUNC symbols.
192 std::vector
<Local_ifunc
> local_ifuncs_
;
195 // The i386 target class.
196 // TLS info comes from
197 // http://people.redhat.com/drepper/tls.pdf
198 // http://www.lsd.ic.unicamp.br/~oliva/writeups/TLS/RFC-TLSDESC-x86.txt
200 class Target_i386
: public Sized_target
<32, false>
203 typedef Output_data_reloc
<elfcpp::SHT_REL
, true, 32, false> Reloc_section
;
206 : Sized_target
<32, false>(&i386_info
),
207 got_(NULL
), plt_(NULL
), got_plt_(NULL
), got_irelative_(NULL
),
208 got_tlsdesc_(NULL
), global_offset_table_(NULL
), rel_dyn_(NULL
),
209 rel_irelative_(NULL
), copy_relocs_(elfcpp::R_386_COPY
), dynbss_(NULL
),
210 got_mod_index_offset_(-1U), tls_base_symbol_defined_(false)
213 // Process the relocations to determine unreferenced sections for
214 // garbage collection.
216 gc_process_relocs(Symbol_table
* symtab
,
218 Sized_relobj_file
<32, false>* object
,
219 unsigned int data_shndx
,
220 unsigned int sh_type
,
221 const unsigned char* prelocs
,
223 Output_section
* output_section
,
224 bool needs_special_offset_handling
,
225 size_t local_symbol_count
,
226 const unsigned char* plocal_symbols
);
228 // Scan the relocations to look for symbol adjustments.
230 scan_relocs(Symbol_table
* symtab
,
232 Sized_relobj_file
<32, false>* object
,
233 unsigned int data_shndx
,
234 unsigned int sh_type
,
235 const unsigned char* prelocs
,
237 Output_section
* output_section
,
238 bool needs_special_offset_handling
,
239 size_t local_symbol_count
,
240 const unsigned char* plocal_symbols
);
242 // Finalize the sections.
244 do_finalize_sections(Layout
*, const Input_objects
*, Symbol_table
*);
246 // Return the value to use for a dynamic which requires special
249 do_dynsym_value(const Symbol
*) const;
251 // Relocate a section.
253 relocate_section(const Relocate_info
<32, false>*,
254 unsigned int sh_type
,
255 const unsigned char* prelocs
,
257 Output_section
* output_section
,
258 bool needs_special_offset_handling
,
260 elfcpp::Elf_types
<32>::Elf_Addr view_address
,
261 section_size_type view_size
,
262 const Reloc_symbol_changes
*);
264 // Scan the relocs during a relocatable link.
266 scan_relocatable_relocs(Symbol_table
* symtab
,
268 Sized_relobj_file
<32, false>* object
,
269 unsigned int data_shndx
,
270 unsigned int sh_type
,
271 const unsigned char* prelocs
,
273 Output_section
* output_section
,
274 bool needs_special_offset_handling
,
275 size_t local_symbol_count
,
276 const unsigned char* plocal_symbols
,
277 Relocatable_relocs
*);
279 // Relocate a section during a relocatable link.
281 relocate_for_relocatable(const Relocate_info
<32, false>*,
282 unsigned int sh_type
,
283 const unsigned char* prelocs
,
285 Output_section
* output_section
,
286 off_t offset_in_output_section
,
287 const Relocatable_relocs
*,
289 elfcpp::Elf_types
<32>::Elf_Addr view_address
,
290 section_size_type view_size
,
291 unsigned char* reloc_view
,
292 section_size_type reloc_view_size
);
294 // Return a string used to fill a code section with nops.
296 do_code_fill(section_size_type length
) const;
298 // Return whether SYM is defined by the ABI.
300 do_is_defined_by_abi(const Symbol
* sym
) const
301 { return strcmp(sym
->name(), "___tls_get_addr") == 0; }
303 // Return whether a symbol name implies a local label. The UnixWare
304 // 2.1 cc generates temporary symbols that start with .X, so we
305 // recognize them here. FIXME: do other SVR4 compilers also use .X?.
306 // If so, we should move the .X recognition into
307 // Target::do_is_local_label_name.
309 do_is_local_label_name(const char* name
) const
311 if (name
[0] == '.' && name
[1] == 'X')
313 return Target::do_is_local_label_name(name
);
316 // Return the PLT address to use for a global symbol.
318 do_plt_address_for_global(const Symbol
* gsym
) const
319 { return this->plt_section()->address_for_global(gsym
); }
322 do_plt_address_for_local(const Relobj
* relobj
, unsigned int symndx
) const
323 { return this->plt_section()->address_for_local(relobj
, symndx
); }
325 // We can tell whether we take the address of a function.
327 do_can_check_for_function_pointers() const
330 // Return the base for a DW_EH_PE_datarel encoding.
332 do_ehframe_datarel_base() const;
334 // Return whether SYM is call to a non-split function.
336 do_is_call_to_non_split(const Symbol
* sym
, unsigned int) const;
338 // Adjust -fsplit-stack code which calls non-split-stack code.
340 do_calls_non_split(Relobj
* object
, unsigned int shndx
,
341 section_offset_type fnoffset
, section_size_type fnsize
,
342 unsigned char* view
, section_size_type view_size
,
343 std::string
* from
, std::string
* to
) const;
345 // Return the size of the GOT section.
349 gold_assert(this->got_
!= NULL
);
350 return this->got_
->data_size();
353 // Return the number of entries in the GOT.
355 got_entry_count() const
357 if (this->got_
== NULL
)
359 return this->got_size() / 4;
362 // Return the number of entries in the PLT.
364 plt_entry_count() const;
366 // Return the offset of the first non-reserved PLT entry.
368 first_plt_entry_offset() const;
370 // Return the size of each PLT entry.
372 plt_entry_size() const;
375 // The class which scans relocations.
380 get_reference_flags(unsigned int r_type
);
383 local(Symbol_table
* symtab
, Layout
* layout
, Target_i386
* target
,
384 Sized_relobj_file
<32, false>* object
,
385 unsigned int data_shndx
,
386 Output_section
* output_section
,
387 const elfcpp::Rel
<32, false>& reloc
, unsigned int r_type
,
388 const elfcpp::Sym
<32, false>& lsym
);
391 global(Symbol_table
* symtab
, Layout
* layout
, Target_i386
* target
,
392 Sized_relobj_file
<32, false>* object
,
393 unsigned int data_shndx
,
394 Output_section
* output_section
,
395 const elfcpp::Rel
<32, false>& reloc
, unsigned int r_type
,
399 local_reloc_may_be_function_pointer(Symbol_table
* symtab
, Layout
* layout
,
401 Sized_relobj_file
<32, false>* object
,
402 unsigned int data_shndx
,
403 Output_section
* output_section
,
404 const elfcpp::Rel
<32, false>& reloc
,
406 const elfcpp::Sym
<32, false>& lsym
);
409 global_reloc_may_be_function_pointer(Symbol_table
* symtab
, Layout
* layout
,
411 Sized_relobj_file
<32, false>* object
,
412 unsigned int data_shndx
,
413 Output_section
* output_section
,
414 const elfcpp::Rel
<32, false>& reloc
,
419 possible_function_pointer_reloc(unsigned int r_type
);
422 reloc_needs_plt_for_ifunc(Sized_relobj_file
<32, false>*,
423 unsigned int r_type
);
426 unsupported_reloc_local(Sized_relobj_file
<32, false>*, unsigned int r_type
);
429 unsupported_reloc_global(Sized_relobj_file
<32, false>*, unsigned int r_type
,
433 // The class which implements relocation.
438 : skip_call_tls_get_addr_(false),
439 local_dynamic_type_(LOCAL_DYNAMIC_NONE
)
444 if (this->skip_call_tls_get_addr_
)
446 // FIXME: This needs to specify the location somehow.
447 gold_error(_("missing expected TLS relocation"));
451 // Return whether the static relocation needs to be applied.
453 should_apply_static_reloc(const Sized_symbol
<32>* gsym
,
456 Output_section
* output_section
);
458 // Do a relocation. Return false if the caller should not issue
459 // any warnings about this relocation.
461 relocate(const Relocate_info
<32, false>*, Target_i386
*, Output_section
*,
462 size_t relnum
, const elfcpp::Rel
<32, false>&,
463 unsigned int r_type
, const Sized_symbol
<32>*,
464 const Symbol_value
<32>*,
465 unsigned char*, elfcpp::Elf_types
<32>::Elf_Addr
,
469 // Do a TLS relocation.
471 relocate_tls(const Relocate_info
<32, false>*, Target_i386
* target
,
472 size_t relnum
, const elfcpp::Rel
<32, false>&,
473 unsigned int r_type
, const Sized_symbol
<32>*,
474 const Symbol_value
<32>*,
475 unsigned char*, elfcpp::Elf_types
<32>::Elf_Addr
,
478 // Do a TLS General-Dynamic to Initial-Exec transition.
480 tls_gd_to_ie(const Relocate_info
<32, false>*, size_t relnum
,
481 Output_segment
* tls_segment
,
482 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
483 elfcpp::Elf_types
<32>::Elf_Addr value
,
485 section_size_type view_size
);
487 // Do a TLS General-Dynamic to Local-Exec transition.
489 tls_gd_to_le(const Relocate_info
<32, false>*, size_t relnum
,
490 Output_segment
* tls_segment
,
491 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
492 elfcpp::Elf_types
<32>::Elf_Addr value
,
494 section_size_type view_size
);
496 // Do a TLS_GOTDESC or TLS_DESC_CALL General-Dynamic to Initial-Exec
499 tls_desc_gd_to_ie(const Relocate_info
<32, false>*, size_t relnum
,
500 Output_segment
* tls_segment
,
501 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
502 elfcpp::Elf_types
<32>::Elf_Addr value
,
504 section_size_type view_size
);
506 // Do a TLS_GOTDESC or TLS_DESC_CALL General-Dynamic to Local-Exec
509 tls_desc_gd_to_le(const Relocate_info
<32, false>*, size_t relnum
,
510 Output_segment
* tls_segment
,
511 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
512 elfcpp::Elf_types
<32>::Elf_Addr value
,
514 section_size_type view_size
);
516 // Do a TLS Local-Dynamic to Local-Exec transition.
518 tls_ld_to_le(const Relocate_info
<32, false>*, size_t relnum
,
519 Output_segment
* tls_segment
,
520 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
521 elfcpp::Elf_types
<32>::Elf_Addr value
,
523 section_size_type view_size
);
525 // Do a TLS Initial-Exec to Local-Exec transition.
527 tls_ie_to_le(const Relocate_info
<32, false>*, size_t relnum
,
528 Output_segment
* tls_segment
,
529 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
530 elfcpp::Elf_types
<32>::Elf_Addr value
,
532 section_size_type view_size
);
534 // We need to keep track of which type of local dynamic relocation
535 // we have seen, so that we can optimize R_386_TLS_LDO_32 correctly.
536 enum Local_dynamic_type
543 // This is set if we should skip the next reloc, which should be a
544 // PLT32 reloc against ___tls_get_addr.
545 bool skip_call_tls_get_addr_
;
546 // The type of local dynamic relocation we have seen in the section
547 // being relocated, if any.
548 Local_dynamic_type local_dynamic_type_
;
551 // A class which returns the size required for a relocation type,
552 // used while scanning relocs during a relocatable link.
553 class Relocatable_size_for_reloc
557 get_size_for_reloc(unsigned int, Relobj
*);
560 // Adjust TLS relocation type based on the options and whether this
561 // is a local symbol.
562 static tls::Tls_optimization
563 optimize_tls_reloc(bool is_final
, int r_type
);
565 // Get the GOT section, creating it if necessary.
566 Output_data_got
<32, false>*
567 got_section(Symbol_table
*, Layout
*);
569 // Get the GOT PLT section.
571 got_plt_section() const
573 gold_assert(this->got_plt_
!= NULL
);
574 return this->got_plt_
;
577 // Get the GOT section for TLSDESC entries.
578 Output_data_got
<32, false>*
579 got_tlsdesc_section() const
581 gold_assert(this->got_tlsdesc_
!= NULL
);
582 return this->got_tlsdesc_
;
585 // Create the PLT section.
587 make_plt_section(Symbol_table
* symtab
, Layout
* layout
);
589 // Create a PLT entry for a global symbol.
591 make_plt_entry(Symbol_table
*, Layout
*, Symbol
*);
593 // Create a PLT entry for a local STT_GNU_IFUNC symbol.
595 make_local_ifunc_plt_entry(Symbol_table
*, Layout
*,
596 Sized_relobj_file
<32, false>* relobj
,
597 unsigned int local_sym_index
);
599 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
601 define_tls_base_symbol(Symbol_table
*, Layout
*);
603 // Create a GOT entry for the TLS module index.
605 got_mod_index_entry(Symbol_table
* symtab
, Layout
* layout
,
606 Sized_relobj_file
<32, false>* object
);
608 // Get the PLT section.
609 Output_data_plt_i386
*
612 gold_assert(this->plt_
!= NULL
);
616 // Get the dynamic reloc section, creating it if necessary.
618 rel_dyn_section(Layout
*);
620 // Get the section to use for TLS_DESC relocations.
622 rel_tls_desc_section(Layout
*) const;
624 // Get the section to use for IRELATIVE relocations.
626 rel_irelative_section(Layout
*);
628 // Add a potential copy relocation.
630 copy_reloc(Symbol_table
* symtab
, Layout
* layout
,
631 Sized_relobj_file
<32, false>* object
,
632 unsigned int shndx
, Output_section
* output_section
,
633 Symbol
* sym
, const elfcpp::Rel
<32, false>& reloc
)
635 this->copy_relocs_
.copy_reloc(symtab
, layout
,
636 symtab
->get_sized_symbol
<32>(sym
),
637 object
, shndx
, output_section
, reloc
,
638 this->rel_dyn_section(layout
));
641 // Information about this specific target which we pass to the
642 // general Target structure.
643 static const Target::Target_info i386_info
;
645 // The types of GOT entries needed for this platform.
646 // These values are exposed to the ABI in an incremental link.
647 // Do not renumber existing values without changing the version
648 // number of the .gnu_incremental_inputs section.
651 GOT_TYPE_STANDARD
= 0, // GOT entry for a regular symbol
652 GOT_TYPE_TLS_NOFFSET
= 1, // GOT entry for negative TLS offset
653 GOT_TYPE_TLS_OFFSET
= 2, // GOT entry for positive TLS offset
654 GOT_TYPE_TLS_PAIR
= 3, // GOT entry for TLS module/offset pair
655 GOT_TYPE_TLS_DESC
= 4 // GOT entry for TLS_DESC pair
659 Output_data_got
<32, false>* got_
;
661 Output_data_plt_i386
* plt_
;
662 // The GOT PLT section.
663 Output_data_space
* got_plt_
;
664 // The GOT section for IRELATIVE relocations.
665 Output_data_space
* got_irelative_
;
666 // The GOT section for TLSDESC relocations.
667 Output_data_got
<32, false>* got_tlsdesc_
;
668 // The _GLOBAL_OFFSET_TABLE_ symbol.
669 Symbol
* global_offset_table_
;
670 // The dynamic reloc section.
671 Reloc_section
* rel_dyn_
;
672 // The section to use for IRELATIVE relocs.
673 Reloc_section
* rel_irelative_
;
674 // Relocs saved to avoid a COPY reloc.
675 Copy_relocs
<elfcpp::SHT_REL
, 32, false> copy_relocs_
;
676 // Space for variables copied with a COPY reloc.
677 Output_data_space
* dynbss_
;
678 // Offset of the GOT entry for the TLS module index.
679 unsigned int got_mod_index_offset_
;
680 // True if the _TLS_MODULE_BASE_ symbol has been defined.
681 bool tls_base_symbol_defined_
;
684 const Target::Target_info
Target_i386::i386_info
=
687 false, // is_big_endian
688 elfcpp::EM_386
, // machine_code
689 false, // has_make_symbol
690 false, // has_resolve
691 true, // has_code_fill
692 true, // is_default_stack_executable
693 true, // can_icf_inline_merge_sections
695 "/usr/lib/libc.so.1", // dynamic_linker
696 0x08048000, // default_text_segment_address
697 0x1000, // abi_pagesize (overridable by -z max-page-size)
698 0x1000, // common_pagesize (overridable by -z common-page-size)
699 elfcpp::SHN_UNDEF
, // small_common_shndx
700 elfcpp::SHN_UNDEF
, // large_common_shndx
701 0, // small_common_section_flags
702 0, // large_common_section_flags
703 NULL
, // attributes_section
704 NULL
// attributes_vendor
707 // Get the GOT section, creating it if necessary.
709 Output_data_got
<32, false>*
710 Target_i386::got_section(Symbol_table
* symtab
, Layout
* layout
)
712 if (this->got_
== NULL
)
714 gold_assert(symtab
!= NULL
&& layout
!= NULL
);
716 this->got_
= new Output_data_got
<32, false>();
718 // When using -z now, we can treat .got.plt as a relro section.
719 // Without -z now, it is modified after program startup by lazy
721 bool is_got_plt_relro
= parameters
->options().now();
722 Output_section_order got_order
= (is_got_plt_relro
725 Output_section_order got_plt_order
= (is_got_plt_relro
727 : ORDER_NON_RELRO_FIRST
);
729 layout
->add_output_section_data(".got", elfcpp::SHT_PROGBITS
,
731 | elfcpp::SHF_WRITE
),
732 this->got_
, got_order
, true);
734 this->got_plt_
= new Output_data_space(4, "** GOT PLT");
735 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
737 | elfcpp::SHF_WRITE
),
738 this->got_plt_
, got_plt_order
,
741 // The first three entries are reserved.
742 this->got_plt_
->set_current_data_size(3 * 4);
744 if (!is_got_plt_relro
)
746 // Those bytes can go into the relro segment.
747 layout
->increase_relro(3 * 4);
750 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
751 this->global_offset_table_
=
752 symtab
->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL
,
753 Symbol_table::PREDEFINED
,
755 0, 0, elfcpp::STT_OBJECT
,
757 elfcpp::STV_HIDDEN
, 0,
760 // If there are any IRELATIVE relocations, they get GOT entries
761 // in .got.plt after the jump slot relocations.
762 this->got_irelative_
= new Output_data_space(4, "** GOT IRELATIVE PLT");
763 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
765 | elfcpp::SHF_WRITE
),
766 this->got_irelative_
,
767 got_plt_order
, is_got_plt_relro
);
769 // If there are any TLSDESC relocations, they get GOT entries in
770 // .got.plt after the jump slot entries.
771 this->got_tlsdesc_
= new Output_data_got
<32, false>();
772 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
774 | elfcpp::SHF_WRITE
),
776 got_plt_order
, is_got_plt_relro
);
782 // Get the dynamic reloc section, creating it if necessary.
784 Target_i386::Reloc_section
*
785 Target_i386::rel_dyn_section(Layout
* layout
)
787 if (this->rel_dyn_
== NULL
)
789 gold_assert(layout
!= NULL
);
790 this->rel_dyn_
= new Reloc_section(parameters
->options().combreloc());
791 layout
->add_output_section_data(".rel.dyn", elfcpp::SHT_REL
,
792 elfcpp::SHF_ALLOC
, this->rel_dyn_
,
793 ORDER_DYNAMIC_RELOCS
, false);
795 return this->rel_dyn_
;
798 // Get the section to use for IRELATIVE relocs, creating it if
799 // necessary. These go in .rel.dyn, but only after all other dynamic
800 // relocations. They need to follow the other dynamic relocations so
801 // that they can refer to global variables initialized by those
804 Target_i386::Reloc_section
*
805 Target_i386::rel_irelative_section(Layout
* layout
)
807 if (this->rel_irelative_
== NULL
)
809 // Make sure we have already create the dynamic reloc section.
810 this->rel_dyn_section(layout
);
811 this->rel_irelative_
= new Reloc_section(false);
812 layout
->add_output_section_data(".rel.dyn", elfcpp::SHT_REL
,
813 elfcpp::SHF_ALLOC
, this->rel_irelative_
,
814 ORDER_DYNAMIC_RELOCS
, false);
815 gold_assert(this->rel_dyn_
->output_section()
816 == this->rel_irelative_
->output_section());
818 return this->rel_irelative_
;
821 // Create the PLT section. The ordinary .got section is an argument,
822 // since we need to refer to the start. We also create our own .got
823 // section just for PLT entries.
825 Output_data_plt_i386::Output_data_plt_i386(Layout
* layout
,
826 Output_data_space
* got_plt
,
827 Output_data_space
* got_irelative
)
828 : Output_section_data(16), layout_(layout
), tls_desc_rel_(NULL
),
829 irelative_rel_(NULL
), got_plt_(got_plt
), got_irelative_(got_irelative
),
830 count_(0), irelative_count_(0), global_ifuncs_(), local_ifuncs_()
832 this->rel_
= new Reloc_section(false);
833 layout
->add_output_section_data(".rel.plt", elfcpp::SHT_REL
,
834 elfcpp::SHF_ALLOC
, this->rel_
,
835 ORDER_DYNAMIC_PLT_RELOCS
, false);
837 // Add unwind information if requested.
838 if (parameters
->options().ld_generated_unwind_info())
839 layout
->add_eh_frame_for_plt(this, plt_eh_frame_cie
, plt_eh_frame_cie_size
,
840 plt_eh_frame_fde
, plt_eh_frame_fde_size
);
844 Output_data_plt_i386::do_adjust_output_section(Output_section
* os
)
846 // UnixWare sets the entsize of .plt to 4, and so does the old GNU
847 // linker, and so do we.
851 // Add an entry to the PLT.
854 Output_data_plt_i386::add_entry(Symbol_table
* symtab
, Layout
* layout
,
857 gold_assert(!gsym
->has_plt_offset());
859 // Every PLT entry needs a reloc.
860 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
861 && gsym
->can_use_relative_reloc(false))
863 gsym
->set_plt_offset(this->irelative_count_
* plt_entry_size
);
864 ++this->irelative_count_
;
865 section_offset_type got_offset
=
866 this->got_irelative_
->current_data_size();
867 this->got_irelative_
->set_current_data_size(got_offset
+ 4);
868 Reloc_section
* rel
= this->rel_irelative(symtab
, layout
);
869 rel
->add_symbolless_global_addend(gsym
, elfcpp::R_386_IRELATIVE
,
870 this->got_irelative_
, got_offset
);
871 struct Global_ifunc gi
;
873 gi
.got_offset
= got_offset
;
874 this->global_ifuncs_
.push_back(gi
);
878 // When setting the PLT offset we skip the initial reserved PLT
880 gsym
->set_plt_offset((this->count_
+ 1) * plt_entry_size
);
884 section_offset_type got_offset
= this->got_plt_
->current_data_size();
886 // Every PLT entry needs a GOT entry which points back to the
887 // PLT entry (this will be changed by the dynamic linker,
888 // normally lazily when the function is called).
889 this->got_plt_
->set_current_data_size(got_offset
+ 4);
891 gsym
->set_needs_dynsym_entry();
892 this->rel_
->add_global(gsym
, elfcpp::R_386_JUMP_SLOT
, this->got_plt_
,
896 // Note that we don't need to save the symbol. The contents of the
897 // PLT are independent of which symbols are used. The symbols only
898 // appear in the relocations.
901 // Add an entry to the PLT for a local STT_GNU_IFUNC symbol. Return
905 Output_data_plt_i386::add_local_ifunc_entry(
906 Symbol_table
* symtab
,
908 Sized_relobj_file
<32, false>* relobj
,
909 unsigned int local_sym_index
)
911 unsigned int plt_offset
= this->irelative_count_
* plt_entry_size
;
912 ++this->irelative_count_
;
914 section_offset_type got_offset
= this->got_irelative_
->current_data_size();
916 // Every PLT entry needs a GOT entry which points back to the PLT
918 this->got_irelative_
->set_current_data_size(got_offset
+ 4);
920 // Every PLT entry needs a reloc.
921 Reloc_section
* rel
= this->rel_irelative(symtab
, layout
);
922 rel
->add_symbolless_local_addend(relobj
, local_sym_index
,
923 elfcpp::R_386_IRELATIVE
,
924 this->got_irelative_
, got_offset
);
926 struct Local_ifunc li
;
928 li
.local_sym_index
= local_sym_index
;
929 li
.got_offset
= got_offset
;
930 this->local_ifuncs_
.push_back(li
);
935 // Return where the TLS_DESC relocations should go, creating it if
936 // necessary. These follow the JUMP_SLOT relocations.
938 Output_data_plt_i386::Reloc_section
*
939 Output_data_plt_i386::rel_tls_desc(Layout
* layout
)
941 if (this->tls_desc_rel_
== NULL
)
943 this->tls_desc_rel_
= new Reloc_section(false);
944 layout
->add_output_section_data(".rel.plt", elfcpp::SHT_REL
,
945 elfcpp::SHF_ALLOC
, this->tls_desc_rel_
,
946 ORDER_DYNAMIC_PLT_RELOCS
, false);
947 gold_assert(this->tls_desc_rel_
->output_section()
948 == this->rel_
->output_section());
950 return this->tls_desc_rel_
;
953 // Return where the IRELATIVE relocations should go in the PLT. These
954 // follow the JUMP_SLOT and TLS_DESC relocations.
956 Output_data_plt_i386::Reloc_section
*
957 Output_data_plt_i386::rel_irelative(Symbol_table
* symtab
, Layout
* layout
)
959 if (this->irelative_rel_
== NULL
)
961 // Make sure we have a place for the TLS_DESC relocations, in
962 // case we see any later on.
963 this->rel_tls_desc(layout
);
964 this->irelative_rel_
= new Reloc_section(false);
965 layout
->add_output_section_data(".rel.plt", elfcpp::SHT_REL
,
966 elfcpp::SHF_ALLOC
, this->irelative_rel_
,
967 ORDER_DYNAMIC_PLT_RELOCS
, false);
968 gold_assert(this->irelative_rel_
->output_section()
969 == this->rel_
->output_section());
971 if (parameters
->doing_static_link())
973 // A statically linked executable will only have a .rel.plt
974 // section to hold R_386_IRELATIVE relocs for STT_GNU_IFUNC
975 // symbols. The library will use these symbols to locate
976 // the IRELATIVE relocs at program startup time.
977 symtab
->define_in_output_data("__rel_iplt_start", NULL
,
978 Symbol_table::PREDEFINED
,
979 this->irelative_rel_
, 0, 0,
980 elfcpp::STT_NOTYPE
, elfcpp::STB_GLOBAL
,
981 elfcpp::STV_HIDDEN
, 0, false, true);
982 symtab
->define_in_output_data("__rel_iplt_end", NULL
,
983 Symbol_table::PREDEFINED
,
984 this->irelative_rel_
, 0, 0,
985 elfcpp::STT_NOTYPE
, elfcpp::STB_GLOBAL
,
986 elfcpp::STV_HIDDEN
, 0, true, true);
989 return this->irelative_rel_
;
992 // Return the PLT address to use for a global symbol.
995 Output_data_plt_i386::address_for_global(const Symbol
* gsym
)
998 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
999 && gsym
->can_use_relative_reloc(false))
1000 offset
= (this->count_
+ 1) * plt_entry_size
;
1001 return this->address() + offset
;
1004 // Return the PLT address to use for a local symbol. These are always
1005 // IRELATIVE relocs.
1008 Output_data_plt_i386::address_for_local(const Relobj
*, unsigned int)
1010 return this->address() + (this->count_
+ 1) * plt_entry_size
;
1013 // The first entry in the PLT for an executable.
1015 const unsigned char Output_data_plt_i386::exec_first_plt_entry
[plt_entry_size
] =
1017 0xff, 0x35, // pushl contents of memory address
1018 0, 0, 0, 0, // replaced with address of .got + 4
1019 0xff, 0x25, // jmp indirect
1020 0, 0, 0, 0, // replaced with address of .got + 8
1021 0, 0, 0, 0 // unused
1024 // The first entry in the PLT for a shared object.
1026 const unsigned char Output_data_plt_i386::dyn_first_plt_entry
[plt_entry_size
] =
1028 0xff, 0xb3, 4, 0, 0, 0, // pushl 4(%ebx)
1029 0xff, 0xa3, 8, 0, 0, 0, // jmp *8(%ebx)
1030 0, 0, 0, 0 // unused
1033 // Subsequent entries in the PLT for an executable.
1035 const unsigned char Output_data_plt_i386::exec_plt_entry
[plt_entry_size
] =
1037 0xff, 0x25, // jmp indirect
1038 0, 0, 0, 0, // replaced with address of symbol in .got
1039 0x68, // pushl immediate
1040 0, 0, 0, 0, // replaced with offset into relocation table
1041 0xe9, // jmp relative
1042 0, 0, 0, 0 // replaced with offset to start of .plt
1045 // Subsequent entries in the PLT for a shared object.
1047 const unsigned char Output_data_plt_i386::dyn_plt_entry
[plt_entry_size
] =
1049 0xff, 0xa3, // jmp *offset(%ebx)
1050 0, 0, 0, 0, // replaced with offset of symbol in .got
1051 0x68, // pushl immediate
1052 0, 0, 0, 0, // replaced with offset into relocation table
1053 0xe9, // jmp relative
1054 0, 0, 0, 0 // replaced with offset to start of .plt
1057 // The .eh_frame unwind information for the PLT.
1060 Output_data_plt_i386::plt_eh_frame_cie
[plt_eh_frame_cie_size
] =
1063 'z', // Augmentation: augmentation size included.
1064 'R', // Augmentation: FDE encoding included.
1065 '\0', // End of augmentation string.
1066 1, // Code alignment factor.
1067 0x7c, // Data alignment factor.
1068 8, // Return address column.
1069 1, // Augmentation size.
1070 (elfcpp::DW_EH_PE_pcrel
// FDE encoding.
1071 | elfcpp::DW_EH_PE_sdata4
),
1072 elfcpp::DW_CFA_def_cfa
, 4, 4, // DW_CFA_def_cfa: r4 (esp) ofs 4.
1073 elfcpp::DW_CFA_offset
+ 8, 1, // DW_CFA_offset: r8 (eip) at cfa-4.
1074 elfcpp::DW_CFA_nop
, // Align to 16 bytes.
1079 Output_data_plt_i386::plt_eh_frame_fde
[plt_eh_frame_fde_size
] =
1081 0, 0, 0, 0, // Replaced with offset to .plt.
1082 0, 0, 0, 0, // Replaced with size of .plt.
1083 0, // Augmentation size.
1084 elfcpp::DW_CFA_def_cfa_offset
, 8, // DW_CFA_def_cfa_offset: 8.
1085 elfcpp::DW_CFA_advance_loc
+ 6, // Advance 6 to __PLT__ + 6.
1086 elfcpp::DW_CFA_def_cfa_offset
, 12, // DW_CFA_def_cfa_offset: 12.
1087 elfcpp::DW_CFA_advance_loc
+ 10, // Advance 10 to __PLT__ + 16.
1088 elfcpp::DW_CFA_def_cfa_expression
, // DW_CFA_def_cfa_expression.
1089 11, // Block length.
1090 elfcpp::DW_OP_breg4
, 4, // Push %esp + 4.
1091 elfcpp::DW_OP_breg8
, 0, // Push %eip.
1092 elfcpp::DW_OP_lit15
, // Push 0xf.
1093 elfcpp::DW_OP_and
, // & (%eip & 0xf).
1094 elfcpp::DW_OP_lit11
, // Push 0xb.
1095 elfcpp::DW_OP_ge
, // >= ((%eip & 0xf) >= 0xb)
1096 elfcpp::DW_OP_lit2
, // Push 2.
1097 elfcpp::DW_OP_shl
, // << (((%eip & 0xf) >= 0xb) << 2)
1098 elfcpp::DW_OP_plus
, // + ((((%eip&0xf)>=0xb)<<2)+%esp+4
1099 elfcpp::DW_CFA_nop
, // Align to 32 bytes.
1105 // Write out the PLT. This uses the hand-coded instructions above,
1106 // and adjusts them as needed. This is all specified by the i386 ELF
1107 // Processor Supplement.
1110 Output_data_plt_i386::do_write(Output_file
* of
)
1112 const off_t offset
= this->offset();
1113 const section_size_type oview_size
=
1114 convert_to_section_size_type(this->data_size());
1115 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
1117 const off_t got_file_offset
= this->got_plt_
->offset();
1118 gold_assert(parameters
->incremental_update()
1119 || (got_file_offset
+ this->got_plt_
->data_size()
1120 == this->got_irelative_
->offset()));
1121 const section_size_type got_size
=
1122 convert_to_section_size_type(this->got_plt_
->data_size()
1123 + this->got_irelative_
->data_size());
1124 unsigned char* const got_view
= of
->get_output_view(got_file_offset
,
1127 unsigned char* pov
= oview
;
1129 elfcpp::Elf_types
<32>::Elf_Addr plt_address
= this->address();
1130 elfcpp::Elf_types
<32>::Elf_Addr got_address
= this->got_plt_
->address();
1132 if (parameters
->options().output_is_position_independent())
1133 memcpy(pov
, dyn_first_plt_entry
, plt_entry_size
);
1136 memcpy(pov
, exec_first_plt_entry
, plt_entry_size
);
1137 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2, got_address
+ 4);
1138 elfcpp::Swap
<32, false>::writeval(pov
+ 8, got_address
+ 8);
1140 pov
+= plt_entry_size
;
1142 unsigned char* got_pov
= got_view
;
1144 // The first entry in the GOT is the address of the .dynamic section
1145 // aka the PT_DYNAMIC segment. The next two entries are reserved.
1146 // We saved space for them when we created the section in
1147 // Target_i386::got_section.
1148 Output_section
* dynamic
= this->layout_
->dynamic_section();
1149 uint32_t dynamic_addr
= dynamic
== NULL
? 0 : dynamic
->address();
1150 elfcpp::Swap
<32, false>::writeval(got_pov
, dynamic_addr
);
1152 memset(got_pov
, 0, 8);
1155 const int rel_size
= elfcpp::Elf_sizes
<32>::rel_size
;
1157 unsigned int plt_offset
= plt_entry_size
;
1158 unsigned int plt_rel_offset
= 0;
1159 unsigned int got_offset
= 12;
1160 const unsigned int count
= this->count_
+ this->irelative_count_
;
1161 for (unsigned int i
= 0;
1164 pov
+= plt_entry_size
,
1166 plt_offset
+= plt_entry_size
,
1167 plt_rel_offset
+= rel_size
,
1170 // Set and adjust the PLT entry itself.
1172 if (parameters
->options().output_is_position_independent())
1174 memcpy(pov
, dyn_plt_entry
, plt_entry_size
);
1175 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2, got_offset
);
1179 memcpy(pov
, exec_plt_entry
, plt_entry_size
);
1180 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
1185 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 7, plt_rel_offset
);
1186 elfcpp::Swap
<32, false>::writeval(pov
+ 12,
1187 - (plt_offset
+ plt_entry_size
));
1189 // Set the entry in the GOT.
1190 elfcpp::Swap
<32, false>::writeval(got_pov
, plt_address
+ plt_offset
+ 6);
1193 // If any STT_GNU_IFUNC symbols have PLT entries, we need to change
1194 // the GOT to point to the actual symbol value, rather than point to
1195 // the PLT entry. That will let the dynamic linker call the right
1196 // function when resolving IRELATIVE relocations.
1197 unsigned char* got_irelative_view
= got_view
+ this->got_plt_
->data_size();
1198 for (std::vector
<Global_ifunc
>::const_iterator p
=
1199 this->global_ifuncs_
.begin();
1200 p
!= this->global_ifuncs_
.end();
1203 const Sized_symbol
<32>* ssym
=
1204 static_cast<const Sized_symbol
<32>*>(p
->sym
);
1205 elfcpp::Swap
<32, false>::writeval(got_irelative_view
+ p
->got_offset
,
1209 for (std::vector
<Local_ifunc
>::const_iterator p
=
1210 this->local_ifuncs_
.begin();
1211 p
!= this->local_ifuncs_
.end();
1214 const Symbol_value
<32>* psymval
=
1215 p
->object
->local_symbol(p
->local_sym_index
);
1216 elfcpp::Swap
<32, false>::writeval(got_irelative_view
+ p
->got_offset
,
1217 psymval
->value(p
->object
, 0));
1220 gold_assert(static_cast<section_size_type
>(pov
- oview
) == oview_size
);
1221 gold_assert(static_cast<section_size_type
>(got_pov
- got_view
) == got_size
);
1223 of
->write_output_view(offset
, oview_size
, oview
);
1224 of
->write_output_view(got_file_offset
, got_size
, got_view
);
1227 // Create the PLT section.
1230 Target_i386::make_plt_section(Symbol_table
* symtab
, Layout
* layout
)
1232 if (this->plt_
== NULL
)
1234 // Create the GOT sections first.
1235 this->got_section(symtab
, layout
);
1237 this->plt_
= new Output_data_plt_i386(layout
, this->got_plt_
,
1238 this->got_irelative_
);
1239 layout
->add_output_section_data(".plt", elfcpp::SHT_PROGBITS
,
1241 | elfcpp::SHF_EXECINSTR
),
1242 this->plt_
, ORDER_PLT
, false);
1244 // Make the sh_info field of .rel.plt point to .plt.
1245 Output_section
* rel_plt_os
= this->plt_
->rel_plt()->output_section();
1246 rel_plt_os
->set_info_section(this->plt_
->output_section());
1250 // Create a PLT entry for a global symbol.
1253 Target_i386::make_plt_entry(Symbol_table
* symtab
, Layout
* layout
, Symbol
* gsym
)
1255 if (gsym
->has_plt_offset())
1257 if (this->plt_
== NULL
)
1258 this->make_plt_section(symtab
, layout
);
1259 this->plt_
->add_entry(symtab
, layout
, gsym
);
1262 // Make a PLT entry for a local STT_GNU_IFUNC symbol.
1265 Target_i386::make_local_ifunc_plt_entry(Symbol_table
* symtab
, Layout
* layout
,
1266 Sized_relobj_file
<32, false>* relobj
,
1267 unsigned int local_sym_index
)
1269 if (relobj
->local_has_plt_offset(local_sym_index
))
1271 if (this->plt_
== NULL
)
1272 this->make_plt_section(symtab
, layout
);
1273 unsigned int plt_offset
= this->plt_
->add_local_ifunc_entry(symtab
, layout
,
1276 relobj
->set_local_plt_offset(local_sym_index
, plt_offset
);
1279 // Return the number of entries in the PLT.
1282 Target_i386::plt_entry_count() const
1284 if (this->plt_
== NULL
)
1286 return this->plt_
->entry_count();
1289 // Return the offset of the first non-reserved PLT entry.
1292 Target_i386::first_plt_entry_offset() const
1294 return Output_data_plt_i386::first_plt_entry_offset();
1297 // Return the size of each PLT entry.
1300 Target_i386::plt_entry_size() const
1302 return Output_data_plt_i386::get_plt_entry_size();
1305 // Get the section to use for TLS_DESC relocations.
1307 Target_i386::Reloc_section
*
1308 Target_i386::rel_tls_desc_section(Layout
* layout
) const
1310 return this->plt_section()->rel_tls_desc(layout
);
1313 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
1316 Target_i386::define_tls_base_symbol(Symbol_table
* symtab
, Layout
* layout
)
1318 if (this->tls_base_symbol_defined_
)
1321 Output_segment
* tls_segment
= layout
->tls_segment();
1322 if (tls_segment
!= NULL
)
1324 bool is_exec
= parameters
->options().output_is_executable();
1325 symtab
->define_in_output_segment("_TLS_MODULE_BASE_", NULL
,
1326 Symbol_table::PREDEFINED
,
1330 elfcpp::STV_HIDDEN
, 0,
1332 ? Symbol::SEGMENT_END
1333 : Symbol::SEGMENT_START
),
1336 this->tls_base_symbol_defined_
= true;
1339 // Create a GOT entry for the TLS module index.
1342 Target_i386::got_mod_index_entry(Symbol_table
* symtab
, Layout
* layout
,
1343 Sized_relobj_file
<32, false>* object
)
1345 if (this->got_mod_index_offset_
== -1U)
1347 gold_assert(symtab
!= NULL
&& layout
!= NULL
&& object
!= NULL
);
1348 Reloc_section
* rel_dyn
= this->rel_dyn_section(layout
);
1349 Output_data_got
<32, false>* got
= this->got_section(symtab
, layout
);
1350 unsigned int got_offset
= got
->add_constant(0);
1351 rel_dyn
->add_local(object
, 0, elfcpp::R_386_TLS_DTPMOD32
, got
,
1353 got
->add_constant(0);
1354 this->got_mod_index_offset_
= got_offset
;
1356 return this->got_mod_index_offset_
;
1359 // Optimize the TLS relocation type based on what we know about the
1360 // symbol. IS_FINAL is true if the final address of this symbol is
1361 // known at link time.
1363 tls::Tls_optimization
1364 Target_i386::optimize_tls_reloc(bool is_final
, int r_type
)
1366 // If we are generating a shared library, then we can't do anything
1368 if (parameters
->options().shared())
1369 return tls::TLSOPT_NONE
;
1373 case elfcpp::R_386_TLS_GD
:
1374 case elfcpp::R_386_TLS_GOTDESC
:
1375 case elfcpp::R_386_TLS_DESC_CALL
:
1376 // These are General-Dynamic which permits fully general TLS
1377 // access. Since we know that we are generating an executable,
1378 // we can convert this to Initial-Exec. If we also know that
1379 // this is a local symbol, we can further switch to Local-Exec.
1381 return tls::TLSOPT_TO_LE
;
1382 return tls::TLSOPT_TO_IE
;
1384 case elfcpp::R_386_TLS_LDM
:
1385 // This is Local-Dynamic, which refers to a local symbol in the
1386 // dynamic TLS block. Since we know that we generating an
1387 // executable, we can switch to Local-Exec.
1388 return tls::TLSOPT_TO_LE
;
1390 case elfcpp::R_386_TLS_LDO_32
:
1391 // Another type of Local-Dynamic relocation.
1392 return tls::TLSOPT_TO_LE
;
1394 case elfcpp::R_386_TLS_IE
:
1395 case elfcpp::R_386_TLS_GOTIE
:
1396 case elfcpp::R_386_TLS_IE_32
:
1397 // These are Initial-Exec relocs which get the thread offset
1398 // from the GOT. If we know that we are linking against the
1399 // local symbol, we can switch to Local-Exec, which links the
1400 // thread offset into the instruction.
1402 return tls::TLSOPT_TO_LE
;
1403 return tls::TLSOPT_NONE
;
1405 case elfcpp::R_386_TLS_LE
:
1406 case elfcpp::R_386_TLS_LE_32
:
1407 // When we already have Local-Exec, there is nothing further we
1409 return tls::TLSOPT_NONE
;
1416 // Get the Reference_flags for a particular relocation.
1419 Target_i386::Scan::get_reference_flags(unsigned int r_type
)
1423 case elfcpp::R_386_NONE
:
1424 case elfcpp::R_386_GNU_VTINHERIT
:
1425 case elfcpp::R_386_GNU_VTENTRY
:
1426 case elfcpp::R_386_GOTPC
:
1427 // No symbol reference.
1430 case elfcpp::R_386_32
:
1431 case elfcpp::R_386_16
:
1432 case elfcpp::R_386_8
:
1433 return Symbol::ABSOLUTE_REF
;
1435 case elfcpp::R_386_PC32
:
1436 case elfcpp::R_386_PC16
:
1437 case elfcpp::R_386_PC8
:
1438 case elfcpp::R_386_GOTOFF
:
1439 return Symbol::RELATIVE_REF
;
1441 case elfcpp::R_386_PLT32
:
1442 return Symbol::FUNCTION_CALL
| Symbol::RELATIVE_REF
;
1444 case elfcpp::R_386_GOT32
:
1446 return Symbol::ABSOLUTE_REF
;
1448 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1449 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
1450 case elfcpp::R_386_TLS_DESC_CALL
:
1451 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1452 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1453 case elfcpp::R_386_TLS_IE
: // Initial-exec
1454 case elfcpp::R_386_TLS_IE_32
:
1455 case elfcpp::R_386_TLS_GOTIE
:
1456 case elfcpp::R_386_TLS_LE
: // Local-exec
1457 case elfcpp::R_386_TLS_LE_32
:
1458 return Symbol::TLS_REF
;
1460 case elfcpp::R_386_COPY
:
1461 case elfcpp::R_386_GLOB_DAT
:
1462 case elfcpp::R_386_JUMP_SLOT
:
1463 case elfcpp::R_386_RELATIVE
:
1464 case elfcpp::R_386_IRELATIVE
:
1465 case elfcpp::R_386_TLS_TPOFF
:
1466 case elfcpp::R_386_TLS_DTPMOD32
:
1467 case elfcpp::R_386_TLS_DTPOFF32
:
1468 case elfcpp::R_386_TLS_TPOFF32
:
1469 case elfcpp::R_386_TLS_DESC
:
1470 case elfcpp::R_386_32PLT
:
1471 case elfcpp::R_386_TLS_GD_32
:
1472 case elfcpp::R_386_TLS_GD_PUSH
:
1473 case elfcpp::R_386_TLS_GD_CALL
:
1474 case elfcpp::R_386_TLS_GD_POP
:
1475 case elfcpp::R_386_TLS_LDM_32
:
1476 case elfcpp::R_386_TLS_LDM_PUSH
:
1477 case elfcpp::R_386_TLS_LDM_CALL
:
1478 case elfcpp::R_386_TLS_LDM_POP
:
1479 case elfcpp::R_386_USED_BY_INTEL_200
:
1481 // Not expected. We will give an error later.
1486 // Report an unsupported relocation against a local symbol.
1489 Target_i386::Scan::unsupported_reloc_local(Sized_relobj_file
<32, false>* object
,
1490 unsigned int r_type
)
1492 gold_error(_("%s: unsupported reloc %u against local symbol"),
1493 object
->name().c_str(), r_type
);
1496 // Return whether we need to make a PLT entry for a relocation of a
1497 // given type against a STT_GNU_IFUNC symbol.
1500 Target_i386::Scan::reloc_needs_plt_for_ifunc(
1501 Sized_relobj_file
<32, false>* object
,
1502 unsigned int r_type
)
1504 int flags
= Scan::get_reference_flags(r_type
);
1505 if (flags
& Symbol::TLS_REF
)
1506 gold_error(_("%s: unsupported TLS reloc %u for IFUNC symbol"),
1507 object
->name().c_str(), r_type
);
1511 // Scan a relocation for a local symbol.
1514 Target_i386::Scan::local(Symbol_table
* symtab
,
1516 Target_i386
* target
,
1517 Sized_relobj_file
<32, false>* object
,
1518 unsigned int data_shndx
,
1519 Output_section
* output_section
,
1520 const elfcpp::Rel
<32, false>& reloc
,
1521 unsigned int r_type
,
1522 const elfcpp::Sym
<32, false>& lsym
)
1524 // A local STT_GNU_IFUNC symbol may require a PLT entry.
1525 if (lsym
.get_st_type() == elfcpp::STT_GNU_IFUNC
1526 && this->reloc_needs_plt_for_ifunc(object
, r_type
))
1528 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1529 target
->make_local_ifunc_plt_entry(symtab
, layout
, object
, r_sym
);
1534 case elfcpp::R_386_NONE
:
1535 case elfcpp::R_386_GNU_VTINHERIT
:
1536 case elfcpp::R_386_GNU_VTENTRY
:
1539 case elfcpp::R_386_32
:
1540 // If building a shared library (or a position-independent
1541 // executable), we need to create a dynamic relocation for
1542 // this location. The relocation applied at link time will
1543 // apply the link-time value, so we flag the location with
1544 // an R_386_RELATIVE relocation so the dynamic loader can
1545 // relocate it easily.
1546 if (parameters
->options().output_is_position_independent())
1548 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1549 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1550 rel_dyn
->add_local_relative(object
, r_sym
, elfcpp::R_386_RELATIVE
,
1551 output_section
, data_shndx
,
1552 reloc
.get_r_offset());
1556 case elfcpp::R_386_16
:
1557 case elfcpp::R_386_8
:
1558 // If building a shared library (or a position-independent
1559 // executable), we need to create a dynamic relocation for
1560 // this location. Because the addend needs to remain in the
1561 // data section, we need to be careful not to apply this
1562 // relocation statically.
1563 if (parameters
->options().output_is_position_independent())
1565 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1566 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1567 if (lsym
.get_st_type() != elfcpp::STT_SECTION
)
1568 rel_dyn
->add_local(object
, r_sym
, r_type
, output_section
,
1569 data_shndx
, reloc
.get_r_offset());
1572 gold_assert(lsym
.get_st_value() == 0);
1573 unsigned int shndx
= lsym
.get_st_shndx();
1575 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
,
1578 object
->error(_("section symbol %u has bad shndx %u"),
1581 rel_dyn
->add_local_section(object
, shndx
,
1582 r_type
, output_section
,
1583 data_shndx
, reloc
.get_r_offset());
1588 case elfcpp::R_386_PC32
:
1589 case elfcpp::R_386_PC16
:
1590 case elfcpp::R_386_PC8
:
1593 case elfcpp::R_386_PLT32
:
1594 // Since we know this is a local symbol, we can handle this as a
1598 case elfcpp::R_386_GOTOFF
:
1599 case elfcpp::R_386_GOTPC
:
1600 // We need a GOT section.
1601 target
->got_section(symtab
, layout
);
1604 case elfcpp::R_386_GOT32
:
1606 // The symbol requires a GOT entry.
1607 Output_data_got
<32, false>* got
= target
->got_section(symtab
, layout
);
1608 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1610 // For a STT_GNU_IFUNC symbol we want the PLT offset. That
1611 // lets function pointers compare correctly with shared
1612 // libraries. Otherwise we would need an IRELATIVE reloc.
1614 if (lsym
.get_st_type() == elfcpp::STT_GNU_IFUNC
)
1615 is_new
= got
->add_local_plt(object
, r_sym
, GOT_TYPE_STANDARD
);
1617 is_new
= got
->add_local(object
, r_sym
, GOT_TYPE_STANDARD
);
1620 // If we are generating a shared object, we need to add a
1621 // dynamic RELATIVE relocation for this symbol's GOT entry.
1622 if (parameters
->options().output_is_position_independent())
1624 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1625 unsigned int got_offset
=
1626 object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
);
1627 rel_dyn
->add_local_relative(object
, r_sym
,
1628 elfcpp::R_386_RELATIVE
,
1635 // These are relocations which should only be seen by the
1636 // dynamic linker, and should never be seen here.
1637 case elfcpp::R_386_COPY
:
1638 case elfcpp::R_386_GLOB_DAT
:
1639 case elfcpp::R_386_JUMP_SLOT
:
1640 case elfcpp::R_386_RELATIVE
:
1641 case elfcpp::R_386_IRELATIVE
:
1642 case elfcpp::R_386_TLS_TPOFF
:
1643 case elfcpp::R_386_TLS_DTPMOD32
:
1644 case elfcpp::R_386_TLS_DTPOFF32
:
1645 case elfcpp::R_386_TLS_TPOFF32
:
1646 case elfcpp::R_386_TLS_DESC
:
1647 gold_error(_("%s: unexpected reloc %u in object file"),
1648 object
->name().c_str(), r_type
);
1651 // These are initial TLS relocs, which are expected when
1653 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1654 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
1655 case elfcpp::R_386_TLS_DESC_CALL
:
1656 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1657 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1658 case elfcpp::R_386_TLS_IE
: // Initial-exec
1659 case elfcpp::R_386_TLS_IE_32
:
1660 case elfcpp::R_386_TLS_GOTIE
:
1661 case elfcpp::R_386_TLS_LE
: // Local-exec
1662 case elfcpp::R_386_TLS_LE_32
:
1664 bool output_is_shared
= parameters
->options().shared();
1665 const tls::Tls_optimization optimized_type
1666 = Target_i386::optimize_tls_reloc(!output_is_shared
, r_type
);
1669 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1670 if (optimized_type
== tls::TLSOPT_NONE
)
1672 // Create a pair of GOT entries for the module index and
1673 // dtv-relative offset.
1674 Output_data_got
<32, false>* got
1675 = target
->got_section(symtab
, layout
);
1676 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1677 unsigned int shndx
= lsym
.get_st_shndx();
1679 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
, &is_ordinary
);
1681 object
->error(_("local symbol %u has bad shndx %u"),
1684 got
->add_local_pair_with_rel(object
, r_sym
, shndx
,
1686 target
->rel_dyn_section(layout
),
1687 elfcpp::R_386_TLS_DTPMOD32
, 0);
1689 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1690 unsupported_reloc_local(object
, r_type
);
1693 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva)
1694 target
->define_tls_base_symbol(symtab
, layout
);
1695 if (optimized_type
== tls::TLSOPT_NONE
)
1697 // Create a double GOT entry with an R_386_TLS_DESC
1698 // reloc. The R_386_TLS_DESC reloc is resolved
1699 // lazily, so the GOT entry needs to be in an area in
1700 // .got.plt, not .got. Call got_section to make sure
1701 // the section has been created.
1702 target
->got_section(symtab
, layout
);
1703 Output_data_got
<32, false>* got
= target
->got_tlsdesc_section();
1704 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1705 if (!object
->local_has_got_offset(r_sym
, GOT_TYPE_TLS_DESC
))
1707 unsigned int got_offset
= got
->add_constant(0);
1708 // The local symbol value is stored in the second
1710 got
->add_local(object
, r_sym
, GOT_TYPE_TLS_DESC
);
1711 // That set the GOT offset of the local symbol to
1712 // point to the second entry, but we want it to
1713 // point to the first.
1714 object
->set_local_got_offset(r_sym
, GOT_TYPE_TLS_DESC
,
1716 Reloc_section
* rt
= target
->rel_tls_desc_section(layout
);
1717 rt
->add_absolute(elfcpp::R_386_TLS_DESC
, got
, got_offset
);
1720 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1721 unsupported_reloc_local(object
, r_type
);
1724 case elfcpp::R_386_TLS_DESC_CALL
:
1727 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1728 if (optimized_type
== tls::TLSOPT_NONE
)
1730 // Create a GOT entry for the module index.
1731 target
->got_mod_index_entry(symtab
, layout
, object
);
1733 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1734 unsupported_reloc_local(object
, r_type
);
1737 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1740 case elfcpp::R_386_TLS_IE
: // Initial-exec
1741 case elfcpp::R_386_TLS_IE_32
:
1742 case elfcpp::R_386_TLS_GOTIE
:
1743 layout
->set_has_static_tls();
1744 if (optimized_type
== tls::TLSOPT_NONE
)
1746 // For the R_386_TLS_IE relocation, we need to create a
1747 // dynamic relocation when building a shared library.
1748 if (r_type
== elfcpp::R_386_TLS_IE
1749 && parameters
->options().shared())
1751 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1753 = elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1754 rel_dyn
->add_local_relative(object
, r_sym
,
1755 elfcpp::R_386_RELATIVE
,
1756 output_section
, data_shndx
,
1757 reloc
.get_r_offset());
1759 // Create a GOT entry for the tp-relative offset.
1760 Output_data_got
<32, false>* got
1761 = target
->got_section(symtab
, layout
);
1762 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1763 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_IE_32
1764 ? elfcpp::R_386_TLS_TPOFF32
1765 : elfcpp::R_386_TLS_TPOFF
);
1766 unsigned int got_type
= (r_type
== elfcpp::R_386_TLS_IE_32
1767 ? GOT_TYPE_TLS_OFFSET
1768 : GOT_TYPE_TLS_NOFFSET
);
1769 got
->add_local_with_rel(object
, r_sym
, got_type
,
1770 target
->rel_dyn_section(layout
),
1773 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1774 unsupported_reloc_local(object
, r_type
);
1777 case elfcpp::R_386_TLS_LE
: // Local-exec
1778 case elfcpp::R_386_TLS_LE_32
:
1779 layout
->set_has_static_tls();
1780 if (output_is_shared
)
1782 // We need to create a dynamic relocation.
1783 gold_assert(lsym
.get_st_type() != elfcpp::STT_SECTION
);
1784 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1785 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_LE_32
1786 ? elfcpp::R_386_TLS_TPOFF32
1787 : elfcpp::R_386_TLS_TPOFF
);
1788 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1789 rel_dyn
->add_local(object
, r_sym
, dyn_r_type
, output_section
,
1790 data_shndx
, reloc
.get_r_offset());
1800 case elfcpp::R_386_32PLT
:
1801 case elfcpp::R_386_TLS_GD_32
:
1802 case elfcpp::R_386_TLS_GD_PUSH
:
1803 case elfcpp::R_386_TLS_GD_CALL
:
1804 case elfcpp::R_386_TLS_GD_POP
:
1805 case elfcpp::R_386_TLS_LDM_32
:
1806 case elfcpp::R_386_TLS_LDM_PUSH
:
1807 case elfcpp::R_386_TLS_LDM_CALL
:
1808 case elfcpp::R_386_TLS_LDM_POP
:
1809 case elfcpp::R_386_USED_BY_INTEL_200
:
1811 unsupported_reloc_local(object
, r_type
);
1816 // Report an unsupported relocation against a global symbol.
1819 Target_i386::Scan::unsupported_reloc_global(
1820 Sized_relobj_file
<32, false>* object
,
1821 unsigned int r_type
,
1824 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
1825 object
->name().c_str(), r_type
, gsym
->demangled_name().c_str());
1829 Target_i386::Scan::possible_function_pointer_reloc(unsigned int r_type
)
1833 case elfcpp::R_386_32
:
1834 case elfcpp::R_386_16
:
1835 case elfcpp::R_386_8
:
1836 case elfcpp::R_386_GOTOFF
:
1837 case elfcpp::R_386_GOT32
:
1848 Target_i386::Scan::local_reloc_may_be_function_pointer(
1852 Sized_relobj_file
<32, false>* ,
1855 const elfcpp::Rel
<32, false>& ,
1856 unsigned int r_type
,
1857 const elfcpp::Sym
<32, false>&)
1859 return possible_function_pointer_reloc(r_type
);
1863 Target_i386::Scan::global_reloc_may_be_function_pointer(
1867 Sized_relobj_file
<32, false>* ,
1870 const elfcpp::Rel
<32, false>& ,
1871 unsigned int r_type
,
1874 return possible_function_pointer_reloc(r_type
);
1877 // Scan a relocation for a global symbol.
1880 Target_i386::Scan::global(Symbol_table
* symtab
,
1882 Target_i386
* target
,
1883 Sized_relobj_file
<32, false>* object
,
1884 unsigned int data_shndx
,
1885 Output_section
* output_section
,
1886 const elfcpp::Rel
<32, false>& reloc
,
1887 unsigned int r_type
,
1890 // A STT_GNU_IFUNC symbol may require a PLT entry.
1891 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
1892 && this->reloc_needs_plt_for_ifunc(object
, r_type
))
1893 target
->make_plt_entry(symtab
, layout
, gsym
);
1897 case elfcpp::R_386_NONE
:
1898 case elfcpp::R_386_GNU_VTINHERIT
:
1899 case elfcpp::R_386_GNU_VTENTRY
:
1902 case elfcpp::R_386_32
:
1903 case elfcpp::R_386_16
:
1904 case elfcpp::R_386_8
:
1906 // Make a PLT entry if necessary.
1907 if (gsym
->needs_plt_entry())
1909 target
->make_plt_entry(symtab
, layout
, gsym
);
1910 // Since this is not a PC-relative relocation, we may be
1911 // taking the address of a function. In that case we need to
1912 // set the entry in the dynamic symbol table to the address of
1914 if (gsym
->is_from_dynobj() && !parameters
->options().shared())
1915 gsym
->set_needs_dynsym_value();
1917 // Make a dynamic relocation if necessary.
1918 if (gsym
->needs_dynamic_reloc(Scan::get_reference_flags(r_type
)))
1920 if (gsym
->may_need_copy_reloc())
1922 target
->copy_reloc(symtab
, layout
, object
,
1923 data_shndx
, output_section
, gsym
, reloc
);
1925 else if (r_type
== elfcpp::R_386_32
1926 && gsym
->type() == elfcpp::STT_GNU_IFUNC
1927 && gsym
->can_use_relative_reloc(false)
1928 && !gsym
->is_from_dynobj()
1929 && !gsym
->is_undefined()
1930 && !gsym
->is_preemptible())
1932 // Use an IRELATIVE reloc for a locally defined
1933 // STT_GNU_IFUNC symbol. This makes a function
1934 // address in a PIE executable match the address in a
1935 // shared library that it links against.
1936 Reloc_section
* rel_dyn
= target
->rel_irelative_section(layout
);
1937 rel_dyn
->add_symbolless_global_addend(gsym
,
1938 elfcpp::R_386_IRELATIVE
,
1941 reloc
.get_r_offset());
1943 else if (r_type
== elfcpp::R_386_32
1944 && gsym
->can_use_relative_reloc(false))
1946 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1947 rel_dyn
->add_global_relative(gsym
, elfcpp::R_386_RELATIVE
,
1948 output_section
, object
,
1949 data_shndx
, reloc
.get_r_offset());
1953 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1954 rel_dyn
->add_global(gsym
, r_type
, output_section
, object
,
1955 data_shndx
, reloc
.get_r_offset());
1961 case elfcpp::R_386_PC32
:
1962 case elfcpp::R_386_PC16
:
1963 case elfcpp::R_386_PC8
:
1965 // Make a PLT entry if necessary.
1966 if (gsym
->needs_plt_entry())
1968 // These relocations are used for function calls only in
1969 // non-PIC code. For a 32-bit relocation in a shared library,
1970 // we'll need a text relocation anyway, so we can skip the
1971 // PLT entry and let the dynamic linker bind the call directly
1972 // to the target. For smaller relocations, we should use a
1973 // PLT entry to ensure that the call can reach.
1974 if (!parameters
->options().shared()
1975 || r_type
!= elfcpp::R_386_PC32
)
1976 target
->make_plt_entry(symtab
, layout
, gsym
);
1978 // Make a dynamic relocation if necessary.
1979 if (gsym
->needs_dynamic_reloc(Scan::get_reference_flags(r_type
)))
1981 if (gsym
->may_need_copy_reloc())
1983 target
->copy_reloc(symtab
, layout
, object
,
1984 data_shndx
, output_section
, gsym
, reloc
);
1988 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1989 rel_dyn
->add_global(gsym
, r_type
, output_section
, object
,
1990 data_shndx
, reloc
.get_r_offset());
1996 case elfcpp::R_386_GOT32
:
1998 // The symbol requires a GOT entry.
1999 Output_data_got
<32, false>* got
= target
->got_section(symtab
, layout
);
2000 if (gsym
->final_value_is_known())
2002 // For a STT_GNU_IFUNC symbol we want the PLT address.
2003 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
)
2004 got
->add_global_plt(gsym
, GOT_TYPE_STANDARD
);
2006 got
->add_global(gsym
, GOT_TYPE_STANDARD
);
2010 // If this symbol is not fully resolved, we need to add a
2011 // GOT entry with a dynamic relocation.
2012 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
2014 // Use a GLOB_DAT rather than a RELATIVE reloc if:
2016 // 1) The symbol may be defined in some other module.
2018 // 2) We are building a shared library and this is a
2019 // protected symbol; using GLOB_DAT means that the dynamic
2020 // linker can use the address of the PLT in the main
2021 // executable when appropriate so that function address
2022 // comparisons work.
2024 // 3) This is a STT_GNU_IFUNC symbol in position dependent
2025 // code, again so that function address comparisons work.
2026 if (gsym
->is_from_dynobj()
2027 || gsym
->is_undefined()
2028 || gsym
->is_preemptible()
2029 || (gsym
->visibility() == elfcpp::STV_PROTECTED
2030 && parameters
->options().shared())
2031 || (gsym
->type() == elfcpp::STT_GNU_IFUNC
2032 && parameters
->options().output_is_position_independent()))
2033 got
->add_global_with_rel(gsym
, GOT_TYPE_STANDARD
,
2034 rel_dyn
, elfcpp::R_386_GLOB_DAT
);
2037 // For a STT_GNU_IFUNC symbol we want to write the PLT
2038 // offset into the GOT, so that function pointer
2039 // comparisons work correctly.
2041 if (gsym
->type() != elfcpp::STT_GNU_IFUNC
)
2042 is_new
= got
->add_global(gsym
, GOT_TYPE_STANDARD
);
2045 is_new
= got
->add_global_plt(gsym
, GOT_TYPE_STANDARD
);
2046 // Tell the dynamic linker to use the PLT address
2047 // when resolving relocations.
2048 if (gsym
->is_from_dynobj()
2049 && !parameters
->options().shared())
2050 gsym
->set_needs_dynsym_value();
2054 unsigned int got_off
= gsym
->got_offset(GOT_TYPE_STANDARD
);
2055 rel_dyn
->add_global_relative(gsym
, elfcpp::R_386_RELATIVE
,
2063 case elfcpp::R_386_PLT32
:
2064 // If the symbol is fully resolved, this is just a PC32 reloc.
2065 // Otherwise we need a PLT entry.
2066 if (gsym
->final_value_is_known())
2068 // If building a shared library, we can also skip the PLT entry
2069 // if the symbol is defined in the output file and is protected
2071 if (gsym
->is_defined()
2072 && !gsym
->is_from_dynobj()
2073 && !gsym
->is_preemptible())
2075 target
->make_plt_entry(symtab
, layout
, gsym
);
2078 case elfcpp::R_386_GOTOFF
:
2079 case elfcpp::R_386_GOTPC
:
2080 // We need a GOT section.
2081 target
->got_section(symtab
, layout
);
2084 // These are relocations which should only be seen by the
2085 // dynamic linker, and should never be seen here.
2086 case elfcpp::R_386_COPY
:
2087 case elfcpp::R_386_GLOB_DAT
:
2088 case elfcpp::R_386_JUMP_SLOT
:
2089 case elfcpp::R_386_RELATIVE
:
2090 case elfcpp::R_386_IRELATIVE
:
2091 case elfcpp::R_386_TLS_TPOFF
:
2092 case elfcpp::R_386_TLS_DTPMOD32
:
2093 case elfcpp::R_386_TLS_DTPOFF32
:
2094 case elfcpp::R_386_TLS_TPOFF32
:
2095 case elfcpp::R_386_TLS_DESC
:
2096 gold_error(_("%s: unexpected reloc %u in object file"),
2097 object
->name().c_str(), r_type
);
2100 // These are initial tls relocs, which are expected when
2102 case elfcpp::R_386_TLS_GD
: // Global-dynamic
2103 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
2104 case elfcpp::R_386_TLS_DESC_CALL
:
2105 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
2106 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
2107 case elfcpp::R_386_TLS_IE
: // Initial-exec
2108 case elfcpp::R_386_TLS_IE_32
:
2109 case elfcpp::R_386_TLS_GOTIE
:
2110 case elfcpp::R_386_TLS_LE
: // Local-exec
2111 case elfcpp::R_386_TLS_LE_32
:
2113 const bool is_final
= gsym
->final_value_is_known();
2114 const tls::Tls_optimization optimized_type
2115 = Target_i386::optimize_tls_reloc(is_final
, r_type
);
2118 case elfcpp::R_386_TLS_GD
: // Global-dynamic
2119 if (optimized_type
== tls::TLSOPT_NONE
)
2121 // Create a pair of GOT entries for the module index and
2122 // dtv-relative offset.
2123 Output_data_got
<32, false>* got
2124 = target
->got_section(symtab
, layout
);
2125 got
->add_global_pair_with_rel(gsym
, GOT_TYPE_TLS_PAIR
,
2126 target
->rel_dyn_section(layout
),
2127 elfcpp::R_386_TLS_DTPMOD32
,
2128 elfcpp::R_386_TLS_DTPOFF32
);
2130 else if (optimized_type
== tls::TLSOPT_TO_IE
)
2132 // Create a GOT entry for the tp-relative offset.
2133 Output_data_got
<32, false>* got
2134 = target
->got_section(symtab
, layout
);
2135 got
->add_global_with_rel(gsym
, GOT_TYPE_TLS_NOFFSET
,
2136 target
->rel_dyn_section(layout
),
2137 elfcpp::R_386_TLS_TPOFF
);
2139 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2140 unsupported_reloc_global(object
, r_type
, gsym
);
2143 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (~oliva url)
2144 target
->define_tls_base_symbol(symtab
, layout
);
2145 if (optimized_type
== tls::TLSOPT_NONE
)
2147 // Create a double GOT entry with an R_386_TLS_DESC
2148 // reloc. The R_386_TLS_DESC reloc is resolved
2149 // lazily, so the GOT entry needs to be in an area in
2150 // .got.plt, not .got. Call got_section to make sure
2151 // the section has been created.
2152 target
->got_section(symtab
, layout
);
2153 Output_data_got
<32, false>* got
= target
->got_tlsdesc_section();
2154 Reloc_section
* rt
= target
->rel_tls_desc_section(layout
);
2155 got
->add_global_pair_with_rel(gsym
, GOT_TYPE_TLS_DESC
, rt
,
2156 elfcpp::R_386_TLS_DESC
, 0);
2158 else if (optimized_type
== tls::TLSOPT_TO_IE
)
2160 // Create a GOT entry for the tp-relative offset.
2161 Output_data_got
<32, false>* got
2162 = target
->got_section(symtab
, layout
);
2163 got
->add_global_with_rel(gsym
, GOT_TYPE_TLS_NOFFSET
,
2164 target
->rel_dyn_section(layout
),
2165 elfcpp::R_386_TLS_TPOFF
);
2167 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2168 unsupported_reloc_global(object
, r_type
, gsym
);
2171 case elfcpp::R_386_TLS_DESC_CALL
:
2174 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
2175 if (optimized_type
== tls::TLSOPT_NONE
)
2177 // Create a GOT entry for the module index.
2178 target
->got_mod_index_entry(symtab
, layout
, object
);
2180 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2181 unsupported_reloc_global(object
, r_type
, gsym
);
2184 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
2187 case elfcpp::R_386_TLS_IE
: // Initial-exec
2188 case elfcpp::R_386_TLS_IE_32
:
2189 case elfcpp::R_386_TLS_GOTIE
:
2190 layout
->set_has_static_tls();
2191 if (optimized_type
== tls::TLSOPT_NONE
)
2193 // For the R_386_TLS_IE relocation, we need to create a
2194 // dynamic relocation when building a shared library.
2195 if (r_type
== elfcpp::R_386_TLS_IE
2196 && parameters
->options().shared())
2198 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
2199 rel_dyn
->add_global_relative(gsym
, elfcpp::R_386_RELATIVE
,
2200 output_section
, object
,
2202 reloc
.get_r_offset());
2204 // Create a GOT entry for the tp-relative offset.
2205 Output_data_got
<32, false>* got
2206 = target
->got_section(symtab
, layout
);
2207 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_IE_32
2208 ? elfcpp::R_386_TLS_TPOFF32
2209 : elfcpp::R_386_TLS_TPOFF
);
2210 unsigned int got_type
= (r_type
== elfcpp::R_386_TLS_IE_32
2211 ? GOT_TYPE_TLS_OFFSET
2212 : GOT_TYPE_TLS_NOFFSET
);
2213 got
->add_global_with_rel(gsym
, got_type
,
2214 target
->rel_dyn_section(layout
),
2217 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2218 unsupported_reloc_global(object
, r_type
, gsym
);
2221 case elfcpp::R_386_TLS_LE
: // Local-exec
2222 case elfcpp::R_386_TLS_LE_32
:
2223 layout
->set_has_static_tls();
2224 if (parameters
->options().shared())
2226 // We need to create a dynamic relocation.
2227 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_LE_32
2228 ? elfcpp::R_386_TLS_TPOFF32
2229 : elfcpp::R_386_TLS_TPOFF
);
2230 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
2231 rel_dyn
->add_global(gsym
, dyn_r_type
, output_section
, object
,
2232 data_shndx
, reloc
.get_r_offset());
2242 case elfcpp::R_386_32PLT
:
2243 case elfcpp::R_386_TLS_GD_32
:
2244 case elfcpp::R_386_TLS_GD_PUSH
:
2245 case elfcpp::R_386_TLS_GD_CALL
:
2246 case elfcpp::R_386_TLS_GD_POP
:
2247 case elfcpp::R_386_TLS_LDM_32
:
2248 case elfcpp::R_386_TLS_LDM_PUSH
:
2249 case elfcpp::R_386_TLS_LDM_CALL
:
2250 case elfcpp::R_386_TLS_LDM_POP
:
2251 case elfcpp::R_386_USED_BY_INTEL_200
:
2253 unsupported_reloc_global(object
, r_type
, gsym
);
2258 // Process relocations for gc.
2261 Target_i386::gc_process_relocs(Symbol_table
* symtab
,
2263 Sized_relobj_file
<32, false>* object
,
2264 unsigned int data_shndx
,
2266 const unsigned char* prelocs
,
2268 Output_section
* output_section
,
2269 bool needs_special_offset_handling
,
2270 size_t local_symbol_count
,
2271 const unsigned char* plocal_symbols
)
2273 gold::gc_process_relocs
<32, false, Target_i386
, elfcpp::SHT_REL
,
2275 Target_i386::Relocatable_size_for_reloc
>(
2284 needs_special_offset_handling
,
2289 // Scan relocations for a section.
2292 Target_i386::scan_relocs(Symbol_table
* symtab
,
2294 Sized_relobj_file
<32, false>* object
,
2295 unsigned int data_shndx
,
2296 unsigned int sh_type
,
2297 const unsigned char* prelocs
,
2299 Output_section
* output_section
,
2300 bool needs_special_offset_handling
,
2301 size_t local_symbol_count
,
2302 const unsigned char* plocal_symbols
)
2304 if (sh_type
== elfcpp::SHT_RELA
)
2306 gold_error(_("%s: unsupported RELA reloc section"),
2307 object
->name().c_str());
2311 gold::scan_relocs
<32, false, Target_i386
, elfcpp::SHT_REL
,
2321 needs_special_offset_handling
,
2326 // Finalize the sections.
2329 Target_i386::do_finalize_sections(
2331 const Input_objects
*,
2332 Symbol_table
* symtab
)
2334 const Reloc_section
* rel_plt
= (this->plt_
== NULL
2336 : this->plt_
->rel_plt());
2337 layout
->add_target_dynamic_tags(true, this->got_plt_
, rel_plt
,
2338 this->rel_dyn_
, true, false);
2340 // Emit any relocs we saved in an attempt to avoid generating COPY
2342 if (this->copy_relocs_
.any_saved_relocs())
2343 this->copy_relocs_
.emit(this->rel_dyn_section(layout
));
2345 // Set the size of the _GLOBAL_OFFSET_TABLE_ symbol to the size of
2346 // the .got.plt section.
2347 Symbol
* sym
= this->global_offset_table_
;
2350 uint32_t data_size
= this->got_plt_
->current_data_size();
2351 symtab
->get_sized_symbol
<32>(sym
)->set_symsize(data_size
);
2354 if (parameters
->doing_static_link()
2355 && (this->plt_
== NULL
|| !this->plt_
->has_irelative_section()))
2357 // If linking statically, make sure that the __rel_iplt symbols
2358 // were defined if necessary, even if we didn't create a PLT.
2359 static const Define_symbol_in_segment syms
[] =
2362 "__rel_iplt_start", // name
2363 elfcpp::PT_LOAD
, // segment_type
2364 elfcpp::PF_W
, // segment_flags_set
2365 elfcpp::PF(0), // segment_flags_clear
2368 elfcpp::STT_NOTYPE
, // type
2369 elfcpp::STB_GLOBAL
, // binding
2370 elfcpp::STV_HIDDEN
, // visibility
2372 Symbol::SEGMENT_START
, // offset_from_base
2376 "__rel_iplt_end", // name
2377 elfcpp::PT_LOAD
, // segment_type
2378 elfcpp::PF_W
, // segment_flags_set
2379 elfcpp::PF(0), // segment_flags_clear
2382 elfcpp::STT_NOTYPE
, // type
2383 elfcpp::STB_GLOBAL
, // binding
2384 elfcpp::STV_HIDDEN
, // visibility
2386 Symbol::SEGMENT_START
, // offset_from_base
2391 symtab
->define_symbols(layout
, 2, syms
,
2392 layout
->script_options()->saw_sections_clause());
2396 // Return whether a direct absolute static relocation needs to be applied.
2397 // In cases where Scan::local() or Scan::global() has created
2398 // a dynamic relocation other than R_386_RELATIVE, the addend
2399 // of the relocation is carried in the data, and we must not
2400 // apply the static relocation.
2403 Target_i386::Relocate::should_apply_static_reloc(const Sized_symbol
<32>* gsym
,
2404 unsigned int r_type
,
2406 Output_section
* output_section
)
2408 // If the output section is not allocated, then we didn't call
2409 // scan_relocs, we didn't create a dynamic reloc, and we must apply
2411 if ((output_section
->flags() & elfcpp::SHF_ALLOC
) == 0)
2414 int ref_flags
= Scan::get_reference_flags(r_type
);
2416 // For local symbols, we will have created a non-RELATIVE dynamic
2417 // relocation only if (a) the output is position independent,
2418 // (b) the relocation is absolute (not pc- or segment-relative), and
2419 // (c) the relocation is not 32 bits wide.
2421 return !(parameters
->options().output_is_position_independent()
2422 && (ref_flags
& Symbol::ABSOLUTE_REF
)
2425 // For global symbols, we use the same helper routines used in the
2426 // scan pass. If we did not create a dynamic relocation, or if we
2427 // created a RELATIVE dynamic relocation, we should apply the static
2429 bool has_dyn
= gsym
->needs_dynamic_reloc(ref_flags
);
2430 bool is_rel
= (ref_flags
& Symbol::ABSOLUTE_REF
)
2431 && gsym
->can_use_relative_reloc(ref_flags
2432 & Symbol::FUNCTION_CALL
);
2433 return !has_dyn
|| is_rel
;
2436 // Perform a relocation.
2439 Target_i386::Relocate::relocate(const Relocate_info
<32, false>* relinfo
,
2440 Target_i386
* target
,
2441 Output_section
* output_section
,
2443 const elfcpp::Rel
<32, false>& rel
,
2444 unsigned int r_type
,
2445 const Sized_symbol
<32>* gsym
,
2446 const Symbol_value
<32>* psymval
,
2447 unsigned char* view
,
2448 elfcpp::Elf_types
<32>::Elf_Addr address
,
2449 section_size_type view_size
)
2451 if (this->skip_call_tls_get_addr_
)
2453 if ((r_type
!= elfcpp::R_386_PLT32
2454 && r_type
!= elfcpp::R_386_PC32
)
2456 || strcmp(gsym
->name(), "___tls_get_addr") != 0)
2457 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2458 _("missing expected TLS relocation"));
2461 this->skip_call_tls_get_addr_
= false;
2466 const Sized_relobj_file
<32, false>* object
= relinfo
->object
;
2468 // Pick the value to use for symbols defined in shared objects.
2469 Symbol_value
<32> symval
;
2471 && gsym
->type() == elfcpp::STT_GNU_IFUNC
2472 && r_type
== elfcpp::R_386_32
2473 && gsym
->needs_dynamic_reloc(Scan::get_reference_flags(r_type
))
2474 && gsym
->can_use_relative_reloc(false)
2475 && !gsym
->is_from_dynobj()
2476 && !gsym
->is_undefined()
2477 && !gsym
->is_preemptible())
2479 // In this case we are generating a R_386_IRELATIVE reloc. We
2480 // want to use the real value of the symbol, not the PLT offset.
2482 else if (gsym
!= NULL
2483 && gsym
->use_plt_offset(Scan::get_reference_flags(r_type
)))
2485 symval
.set_output_value(target
->plt_address_for_global(gsym
)
2486 + gsym
->plt_offset());
2489 else if (gsym
== NULL
&& psymval
->is_ifunc_symbol())
2491 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
2492 if (object
->local_has_plt_offset(r_sym
))
2494 symval
.set_output_value(target
->plt_address_for_local(object
, r_sym
)
2495 + object
->local_plt_offset(r_sym
));
2500 // Get the GOT offset if needed.
2501 // The GOT pointer points to the end of the GOT section.
2502 // We need to subtract the size of the GOT section to get
2503 // the actual offset to use in the relocation.
2504 bool have_got_offset
= false;
2505 unsigned int got_offset
= 0;
2508 case elfcpp::R_386_GOT32
:
2511 gold_assert(gsym
->has_got_offset(GOT_TYPE_STANDARD
));
2512 got_offset
= (gsym
->got_offset(GOT_TYPE_STANDARD
)
2513 - target
->got_size());
2517 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
2518 gold_assert(object
->local_has_got_offset(r_sym
, GOT_TYPE_STANDARD
));
2519 got_offset
= (object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
)
2520 - target
->got_size());
2522 have_got_offset
= true;
2531 case elfcpp::R_386_NONE
:
2532 case elfcpp::R_386_GNU_VTINHERIT
:
2533 case elfcpp::R_386_GNU_VTENTRY
:
2536 case elfcpp::R_386_32
:
2537 if (should_apply_static_reloc(gsym
, r_type
, true, output_section
))
2538 Relocate_functions
<32, false>::rel32(view
, object
, psymval
);
2541 case elfcpp::R_386_PC32
:
2542 if (should_apply_static_reloc(gsym
, r_type
, true, output_section
))
2543 Relocate_functions
<32, false>::pcrel32(view
, object
, psymval
, address
);
2546 case elfcpp::R_386_16
:
2547 if (should_apply_static_reloc(gsym
, r_type
, false, output_section
))
2548 Relocate_functions
<32, false>::rel16(view
, object
, psymval
);
2551 case elfcpp::R_386_PC16
:
2552 if (should_apply_static_reloc(gsym
, r_type
, false, output_section
))
2553 Relocate_functions
<32, false>::pcrel16(view
, object
, psymval
, address
);
2556 case elfcpp::R_386_8
:
2557 if (should_apply_static_reloc(gsym
, r_type
, false, output_section
))
2558 Relocate_functions
<32, false>::rel8(view
, object
, psymval
);
2561 case elfcpp::R_386_PC8
:
2562 if (should_apply_static_reloc(gsym
, r_type
, false, output_section
))
2563 Relocate_functions
<32, false>::pcrel8(view
, object
, psymval
, address
);
2566 case elfcpp::R_386_PLT32
:
2567 gold_assert(gsym
== NULL
2568 || gsym
->has_plt_offset()
2569 || gsym
->final_value_is_known()
2570 || (gsym
->is_defined()
2571 && !gsym
->is_from_dynobj()
2572 && !gsym
->is_preemptible()));
2573 Relocate_functions
<32, false>::pcrel32(view
, object
, psymval
, address
);
2576 case elfcpp::R_386_GOT32
:
2577 gold_assert(have_got_offset
);
2578 Relocate_functions
<32, false>::rel32(view
, got_offset
);
2581 case elfcpp::R_386_GOTOFF
:
2583 elfcpp::Elf_types
<32>::Elf_Addr value
;
2584 value
= (psymval
->value(object
, 0)
2585 - target
->got_plt_section()->address());
2586 Relocate_functions
<32, false>::rel32(view
, value
);
2590 case elfcpp::R_386_GOTPC
:
2592 elfcpp::Elf_types
<32>::Elf_Addr value
;
2593 value
= target
->got_plt_section()->address();
2594 Relocate_functions
<32, false>::pcrel32(view
, value
, address
);
2598 case elfcpp::R_386_COPY
:
2599 case elfcpp::R_386_GLOB_DAT
:
2600 case elfcpp::R_386_JUMP_SLOT
:
2601 case elfcpp::R_386_RELATIVE
:
2602 case elfcpp::R_386_IRELATIVE
:
2603 // These are outstanding tls relocs, which are unexpected when
2605 case elfcpp::R_386_TLS_TPOFF
:
2606 case elfcpp::R_386_TLS_DTPMOD32
:
2607 case elfcpp::R_386_TLS_DTPOFF32
:
2608 case elfcpp::R_386_TLS_TPOFF32
:
2609 case elfcpp::R_386_TLS_DESC
:
2610 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2611 _("unexpected reloc %u in object file"),
2615 // These are initial tls relocs, which are expected when
2617 case elfcpp::R_386_TLS_GD
: // Global-dynamic
2618 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
2619 case elfcpp::R_386_TLS_DESC_CALL
:
2620 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
2621 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
2622 case elfcpp::R_386_TLS_IE
: // Initial-exec
2623 case elfcpp::R_386_TLS_IE_32
:
2624 case elfcpp::R_386_TLS_GOTIE
:
2625 case elfcpp::R_386_TLS_LE
: // Local-exec
2626 case elfcpp::R_386_TLS_LE_32
:
2627 this->relocate_tls(relinfo
, target
, relnum
, rel
, r_type
, gsym
, psymval
,
2628 view
, address
, view_size
);
2631 case elfcpp::R_386_32PLT
:
2632 case elfcpp::R_386_TLS_GD_32
:
2633 case elfcpp::R_386_TLS_GD_PUSH
:
2634 case elfcpp::R_386_TLS_GD_CALL
:
2635 case elfcpp::R_386_TLS_GD_POP
:
2636 case elfcpp::R_386_TLS_LDM_32
:
2637 case elfcpp::R_386_TLS_LDM_PUSH
:
2638 case elfcpp::R_386_TLS_LDM_CALL
:
2639 case elfcpp::R_386_TLS_LDM_POP
:
2640 case elfcpp::R_386_USED_BY_INTEL_200
:
2642 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2643 _("unsupported reloc %u"),
2651 // Perform a TLS relocation.
2654 Target_i386::Relocate::relocate_tls(const Relocate_info
<32, false>* relinfo
,
2655 Target_i386
* target
,
2657 const elfcpp::Rel
<32, false>& rel
,
2658 unsigned int r_type
,
2659 const Sized_symbol
<32>* gsym
,
2660 const Symbol_value
<32>* psymval
,
2661 unsigned char* view
,
2662 elfcpp::Elf_types
<32>::Elf_Addr
,
2663 section_size_type view_size
)
2665 Output_segment
* tls_segment
= relinfo
->layout
->tls_segment();
2667 const Sized_relobj_file
<32, false>* object
= relinfo
->object
;
2669 elfcpp::Elf_types
<32>::Elf_Addr value
= psymval
->value(object
, 0);
2671 const bool is_final
= (gsym
== NULL
2672 ? !parameters
->options().shared()
2673 : gsym
->final_value_is_known());
2674 const tls::Tls_optimization optimized_type
2675 = Target_i386::optimize_tls_reloc(is_final
, r_type
);
2678 case elfcpp::R_386_TLS_GD
: // Global-dynamic
2679 if (optimized_type
== tls::TLSOPT_TO_LE
)
2681 if (tls_segment
== NULL
)
2683 gold_assert(parameters
->errors()->error_count() > 0
2684 || issue_undefined_symbol_error(gsym
));
2687 this->tls_gd_to_le(relinfo
, relnum
, tls_segment
,
2688 rel
, r_type
, value
, view
,
2694 unsigned int got_type
= (optimized_type
== tls::TLSOPT_TO_IE
2695 ? GOT_TYPE_TLS_NOFFSET
2696 : GOT_TYPE_TLS_PAIR
);
2697 unsigned int got_offset
;
2700 gold_assert(gsym
->has_got_offset(got_type
));
2701 got_offset
= gsym
->got_offset(got_type
) - target
->got_size();
2705 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
2706 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
2707 got_offset
= (object
->local_got_offset(r_sym
, got_type
)
2708 - target
->got_size());
2710 if (optimized_type
== tls::TLSOPT_TO_IE
)
2712 this->tls_gd_to_ie(relinfo
, relnum
, tls_segment
, rel
, r_type
,
2713 got_offset
, view
, view_size
);
2716 else if (optimized_type
== tls::TLSOPT_NONE
)
2718 // Relocate the field with the offset of the pair of GOT
2720 Relocate_functions
<32, false>::rel32(view
, got_offset
);
2724 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2725 _("unsupported reloc %u"),
2729 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
2730 case elfcpp::R_386_TLS_DESC_CALL
:
2731 this->local_dynamic_type_
= LOCAL_DYNAMIC_GNU
;
2732 if (optimized_type
== tls::TLSOPT_TO_LE
)
2734 if (tls_segment
== NULL
)
2736 gold_assert(parameters
->errors()->error_count() > 0
2737 || issue_undefined_symbol_error(gsym
));
2740 this->tls_desc_gd_to_le(relinfo
, relnum
, tls_segment
,
2741 rel
, r_type
, value
, view
,
2747 unsigned int got_type
= (optimized_type
== tls::TLSOPT_TO_IE
2748 ? GOT_TYPE_TLS_NOFFSET
2749 : GOT_TYPE_TLS_DESC
);
2750 unsigned int got_offset
= 0;
2751 if (r_type
== elfcpp::R_386_TLS_GOTDESC
2752 && optimized_type
== tls::TLSOPT_NONE
)
2754 // We created GOT entries in the .got.tlsdesc portion of
2755 // the .got.plt section, but the offset stored in the
2756 // symbol is the offset within .got.tlsdesc.
2757 got_offset
= (target
->got_size()
2758 + target
->got_plt_section()->data_size());
2762 gold_assert(gsym
->has_got_offset(got_type
));
2763 got_offset
+= gsym
->got_offset(got_type
) - target
->got_size();
2767 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
2768 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
2769 got_offset
+= (object
->local_got_offset(r_sym
, got_type
)
2770 - target
->got_size());
2772 if (optimized_type
== tls::TLSOPT_TO_IE
)
2774 if (tls_segment
== NULL
)
2776 gold_assert(parameters
->errors()->error_count() > 0
2777 || issue_undefined_symbol_error(gsym
));
2780 this->tls_desc_gd_to_ie(relinfo
, relnum
, tls_segment
, rel
, r_type
,
2781 got_offset
, view
, view_size
);
2784 else if (optimized_type
== tls::TLSOPT_NONE
)
2786 if (r_type
== elfcpp::R_386_TLS_GOTDESC
)
2788 // Relocate the field with the offset of the pair of GOT
2790 Relocate_functions
<32, false>::rel32(view
, got_offset
);
2795 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2796 _("unsupported reloc %u"),
2800 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
2801 if (this->local_dynamic_type_
== LOCAL_DYNAMIC_SUN
)
2803 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2804 _("both SUN and GNU model "
2805 "TLS relocations"));
2808 this->local_dynamic_type_
= LOCAL_DYNAMIC_GNU
;
2809 if (optimized_type
== tls::TLSOPT_TO_LE
)
2811 if (tls_segment
== NULL
)
2813 gold_assert(parameters
->errors()->error_count() > 0
2814 || issue_undefined_symbol_error(gsym
));
2817 this->tls_ld_to_le(relinfo
, relnum
, tls_segment
, rel
, r_type
,
2818 value
, view
, view_size
);
2821 else if (optimized_type
== tls::TLSOPT_NONE
)
2823 // Relocate the field with the offset of the GOT entry for
2824 // the module index.
2825 unsigned int got_offset
;
2826 got_offset
= (target
->got_mod_index_entry(NULL
, NULL
, NULL
)
2827 - target
->got_size());
2828 Relocate_functions
<32, false>::rel32(view
, got_offset
);
2831 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2832 _("unsupported reloc %u"),
2836 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
2837 if (optimized_type
== tls::TLSOPT_TO_LE
)
2839 // This reloc can appear in debugging sections, in which
2840 // case we must not convert to local-exec. We decide what
2841 // to do based on whether the section is marked as
2842 // containing executable code. That is what the GNU linker
2844 elfcpp::Shdr
<32, false> shdr(relinfo
->data_shdr
);
2845 if ((shdr
.get_sh_flags() & elfcpp::SHF_EXECINSTR
) != 0)
2847 if (tls_segment
== NULL
)
2849 gold_assert(parameters
->errors()->error_count() > 0
2850 || issue_undefined_symbol_error(gsym
));
2853 value
-= tls_segment
->memsz();
2856 Relocate_functions
<32, false>::rel32(view
, value
);
2859 case elfcpp::R_386_TLS_IE
: // Initial-exec
2860 case elfcpp::R_386_TLS_GOTIE
:
2861 case elfcpp::R_386_TLS_IE_32
:
2862 if (optimized_type
== tls::TLSOPT_TO_LE
)
2864 if (tls_segment
== NULL
)
2866 gold_assert(parameters
->errors()->error_count() > 0
2867 || issue_undefined_symbol_error(gsym
));
2870 Target_i386::Relocate::tls_ie_to_le(relinfo
, relnum
, tls_segment
,
2871 rel
, r_type
, value
, view
,
2875 else if (optimized_type
== tls::TLSOPT_NONE
)
2877 // Relocate the field with the offset of the GOT entry for
2878 // the tp-relative offset of the symbol.
2879 unsigned int got_type
= (r_type
== elfcpp::R_386_TLS_IE_32
2880 ? GOT_TYPE_TLS_OFFSET
2881 : GOT_TYPE_TLS_NOFFSET
);
2882 unsigned int got_offset
;
2885 gold_assert(gsym
->has_got_offset(got_type
));
2886 got_offset
= gsym
->got_offset(got_type
);
2890 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
2891 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
2892 got_offset
= object
->local_got_offset(r_sym
, got_type
);
2894 // For the R_386_TLS_IE relocation, we need to apply the
2895 // absolute address of the GOT entry.
2896 if (r_type
== elfcpp::R_386_TLS_IE
)
2897 got_offset
+= target
->got_plt_section()->address();
2898 // All GOT offsets are relative to the end of the GOT.
2899 got_offset
-= target
->got_size();
2900 Relocate_functions
<32, false>::rel32(view
, got_offset
);
2903 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2904 _("unsupported reloc %u"),
2908 case elfcpp::R_386_TLS_LE
: // Local-exec
2909 // If we're creating a shared library, a dynamic relocation will
2910 // have been created for this location, so do not apply it now.
2911 if (!parameters
->options().shared())
2913 if (tls_segment
== NULL
)
2915 gold_assert(parameters
->errors()->error_count() > 0
2916 || issue_undefined_symbol_error(gsym
));
2919 value
-= tls_segment
->memsz();
2920 Relocate_functions
<32, false>::rel32(view
, value
);
2924 case elfcpp::R_386_TLS_LE_32
:
2925 // If we're creating a shared library, a dynamic relocation will
2926 // have been created for this location, so do not apply it now.
2927 if (!parameters
->options().shared())
2929 if (tls_segment
== NULL
)
2931 gold_assert(parameters
->errors()->error_count() > 0
2932 || issue_undefined_symbol_error(gsym
));
2935 value
= tls_segment
->memsz() - value
;
2936 Relocate_functions
<32, false>::rel32(view
, value
);
2942 // Do a relocation in which we convert a TLS General-Dynamic to a
2946 Target_i386::Relocate::tls_gd_to_le(const Relocate_info
<32, false>* relinfo
,
2948 Output_segment
* tls_segment
,
2949 const elfcpp::Rel
<32, false>& rel
,
2951 elfcpp::Elf_types
<32>::Elf_Addr value
,
2952 unsigned char* view
,
2953 section_size_type view_size
)
2955 // leal foo(,%reg,1),%eax; call ___tls_get_addr
2956 // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
2957 // leal foo(%reg),%eax; call ___tls_get_addr
2958 // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
2960 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2961 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 9);
2963 unsigned char op1
= view
[-1];
2964 unsigned char op2
= view
[-2];
2966 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2967 op2
== 0x8d || op2
== 0x04);
2968 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[4] == 0xe8);
2974 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -3);
2975 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[-3] == 0x8d);
2976 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2977 ((op1
& 0xc7) == 0x05 && op1
!= (4 << 3)));
2978 memcpy(view
- 3, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
2982 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2983 (op1
& 0xf8) == 0x80 && (op1
& 7) != 4);
2984 if (rel
.get_r_offset() + 9 < view_size
2987 // There is a trailing nop. Use the size byte subl.
2988 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
2993 // Use the five byte subl.
2994 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
2998 value
= tls_segment
->memsz() - value
;
2999 Relocate_functions
<32, false>::rel32(view
+ roff
, value
);
3001 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3003 this->skip_call_tls_get_addr_
= true;
3006 // Do a relocation in which we convert a TLS General-Dynamic to an
3010 Target_i386::Relocate::tls_gd_to_ie(const Relocate_info
<32, false>* relinfo
,
3013 const elfcpp::Rel
<32, false>& rel
,
3015 elfcpp::Elf_types
<32>::Elf_Addr value
,
3016 unsigned char* view
,
3017 section_size_type view_size
)
3019 // leal foo(,%ebx,1),%eax; call ___tls_get_addr
3020 // ==> movl %gs:0,%eax; addl foo@gotntpoff(%ebx),%eax
3022 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
3023 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 9);
3025 unsigned char op1
= view
[-1];
3026 unsigned char op2
= view
[-2];
3028 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3029 op2
== 0x8d || op2
== 0x04);
3030 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[4] == 0xe8);
3034 // FIXME: For now, support only the first (SIB) form.
3035 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), op2
== 0x04);
3039 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -3);
3040 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[-3] == 0x8d);
3041 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3042 ((op1
& 0xc7) == 0x05 && op1
!= (4 << 3)));
3043 memcpy(view
- 3, "\x65\xa1\0\0\0\0\x03\x83\0\0\0", 12);
3047 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3048 (op1
& 0xf8) == 0x80 && (op1
& 7) != 4);
3049 if (rel
.get_r_offset() + 9 < view_size
3052 // FIXME: This is not the right instruction sequence.
3053 // There is a trailing nop. Use the size byte subl.
3054 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
3059 // FIXME: This is not the right instruction sequence.
3060 // Use the five byte subl.
3061 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
3065 Relocate_functions
<32, false>::rel32(view
+ roff
, value
);
3067 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3069 this->skip_call_tls_get_addr_
= true;
3072 // Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL
3073 // General-Dynamic to a Local-Exec.
3076 Target_i386::Relocate::tls_desc_gd_to_le(
3077 const Relocate_info
<32, false>* relinfo
,
3079 Output_segment
* tls_segment
,
3080 const elfcpp::Rel
<32, false>& rel
,
3081 unsigned int r_type
,
3082 elfcpp::Elf_types
<32>::Elf_Addr value
,
3083 unsigned char* view
,
3084 section_size_type view_size
)
3086 if (r_type
== elfcpp::R_386_TLS_GOTDESC
)
3088 // leal foo@TLSDESC(%ebx), %eax
3089 // ==> leal foo@NTPOFF, %eax
3090 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
3091 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
3092 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3093 view
[-2] == 0x8d && view
[-1] == 0x83);
3095 value
-= tls_segment
->memsz();
3096 Relocate_functions
<32, false>::rel32(view
, value
);
3100 // call *foo@TLSCALL(%eax)
3102 gold_assert(r_type
== elfcpp::R_386_TLS_DESC_CALL
);
3103 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 2);
3104 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3105 view
[0] == 0xff && view
[1] == 0x10);
3111 // Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL
3112 // General-Dynamic to an Initial-Exec.
3115 Target_i386::Relocate::tls_desc_gd_to_ie(
3116 const Relocate_info
<32, false>* relinfo
,
3119 const elfcpp::Rel
<32, false>& rel
,
3120 unsigned int r_type
,
3121 elfcpp::Elf_types
<32>::Elf_Addr value
,
3122 unsigned char* view
,
3123 section_size_type view_size
)
3125 if (r_type
== elfcpp::R_386_TLS_GOTDESC
)
3127 // leal foo@TLSDESC(%ebx), %eax
3128 // ==> movl foo@GOTNTPOFF(%ebx), %eax
3129 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
3130 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
3131 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3132 view
[-2] == 0x8d && view
[-1] == 0x83);
3134 Relocate_functions
<32, false>::rel32(view
, value
);
3138 // call *foo@TLSCALL(%eax)
3140 gold_assert(r_type
== elfcpp::R_386_TLS_DESC_CALL
);
3141 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 2);
3142 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3143 view
[0] == 0xff && view
[1] == 0x10);
3149 // Do a relocation in which we convert a TLS Local-Dynamic to a
3153 Target_i386::Relocate::tls_ld_to_le(const Relocate_info
<32, false>* relinfo
,
3156 const elfcpp::Rel
<32, false>& rel
,
3158 elfcpp::Elf_types
<32>::Elf_Addr
,
3159 unsigned char* view
,
3160 section_size_type view_size
)
3162 // leal foo(%reg), %eax; call ___tls_get_addr
3163 // ==> movl %gs:0,%eax; nop; leal 0(%esi,1),%esi
3165 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
3166 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 9);
3168 // FIXME: Does this test really always pass?
3169 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3170 view
[-2] == 0x8d && view
[-1] == 0x83);
3172 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[4] == 0xe8);
3174 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x90\x8d\x74\x26\0", 11);
3176 // The next reloc should be a PLT32 reloc against __tls_get_addr.
3178 this->skip_call_tls_get_addr_
= true;
3181 // Do a relocation in which we convert a TLS Initial-Exec to a
3185 Target_i386::Relocate::tls_ie_to_le(const Relocate_info
<32, false>* relinfo
,
3187 Output_segment
* tls_segment
,
3188 const elfcpp::Rel
<32, false>& rel
,
3189 unsigned int r_type
,
3190 elfcpp::Elf_types
<32>::Elf_Addr value
,
3191 unsigned char* view
,
3192 section_size_type view_size
)
3194 // We have to actually change the instructions, which means that we
3195 // need to examine the opcodes to figure out which instruction we
3197 if (r_type
== elfcpp::R_386_TLS_IE
)
3199 // movl %gs:XX,%eax ==> movl $YY,%eax
3200 // movl %gs:XX,%reg ==> movl $YY,%reg
3201 // addl %gs:XX,%reg ==> addl $YY,%reg
3202 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -1);
3203 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
3205 unsigned char op1
= view
[-1];
3208 // movl XX,%eax ==> movl $YY,%eax
3213 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
3215 unsigned char op2
= view
[-2];
3218 // movl XX,%reg ==> movl $YY,%reg
3219 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3220 (op1
& 0xc7) == 0x05);
3222 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
3224 else if (op2
== 0x03)
3226 // addl XX,%reg ==> addl $YY,%reg
3227 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3228 (op1
& 0xc7) == 0x05);
3230 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
3233 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), 0);
3238 // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2
3239 // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2
3240 // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2
3241 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
3242 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
3244 unsigned char op1
= view
[-1];
3245 unsigned char op2
= view
[-2];
3246 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3247 (op1
& 0xc0) == 0x80 && (op1
& 7) != 4);
3250 // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2
3252 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
3254 else if (op2
== 0x2b)
3256 // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2
3258 view
[-1] = 0xe8 | ((op1
>> 3) & 7);
3260 else if (op2
== 0x03)
3262 // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2
3264 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
3267 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), 0);
3270 value
= tls_segment
->memsz() - value
;
3271 if (r_type
== elfcpp::R_386_TLS_IE
|| r_type
== elfcpp::R_386_TLS_GOTIE
)
3274 Relocate_functions
<32, false>::rel32(view
, value
);
3277 // Relocate section data.
3280 Target_i386::relocate_section(const Relocate_info
<32, false>* relinfo
,
3281 unsigned int sh_type
,
3282 const unsigned char* prelocs
,
3284 Output_section
* output_section
,
3285 bool needs_special_offset_handling
,
3286 unsigned char* view
,
3287 elfcpp::Elf_types
<32>::Elf_Addr address
,
3288 section_size_type view_size
,
3289 const Reloc_symbol_changes
* reloc_symbol_changes
)
3291 gold_assert(sh_type
== elfcpp::SHT_REL
);
3293 gold::relocate_section
<32, false, Target_i386
, elfcpp::SHT_REL
,
3294 Target_i386::Relocate
>(
3300 needs_special_offset_handling
,
3304 reloc_symbol_changes
);
3307 // Return the size of a relocation while scanning during a relocatable
3311 Target_i386::Relocatable_size_for_reloc::get_size_for_reloc(
3312 unsigned int r_type
,
3317 case elfcpp::R_386_NONE
:
3318 case elfcpp::R_386_GNU_VTINHERIT
:
3319 case elfcpp::R_386_GNU_VTENTRY
:
3320 case elfcpp::R_386_TLS_GD
: // Global-dynamic
3321 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
3322 case elfcpp::R_386_TLS_DESC_CALL
:
3323 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
3324 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
3325 case elfcpp::R_386_TLS_IE
: // Initial-exec
3326 case elfcpp::R_386_TLS_IE_32
:
3327 case elfcpp::R_386_TLS_GOTIE
:
3328 case elfcpp::R_386_TLS_LE
: // Local-exec
3329 case elfcpp::R_386_TLS_LE_32
:
3332 case elfcpp::R_386_32
:
3333 case elfcpp::R_386_PC32
:
3334 case elfcpp::R_386_GOT32
:
3335 case elfcpp::R_386_PLT32
:
3336 case elfcpp::R_386_GOTOFF
:
3337 case elfcpp::R_386_GOTPC
:
3340 case elfcpp::R_386_16
:
3341 case elfcpp::R_386_PC16
:
3344 case elfcpp::R_386_8
:
3345 case elfcpp::R_386_PC8
:
3348 // These are relocations which should only be seen by the
3349 // dynamic linker, and should never be seen here.
3350 case elfcpp::R_386_COPY
:
3351 case elfcpp::R_386_GLOB_DAT
:
3352 case elfcpp::R_386_JUMP_SLOT
:
3353 case elfcpp::R_386_RELATIVE
:
3354 case elfcpp::R_386_IRELATIVE
:
3355 case elfcpp::R_386_TLS_TPOFF
:
3356 case elfcpp::R_386_TLS_DTPMOD32
:
3357 case elfcpp::R_386_TLS_DTPOFF32
:
3358 case elfcpp::R_386_TLS_TPOFF32
:
3359 case elfcpp::R_386_TLS_DESC
:
3360 object
->error(_("unexpected reloc %u in object file"), r_type
);
3363 case elfcpp::R_386_32PLT
:
3364 case elfcpp::R_386_TLS_GD_32
:
3365 case elfcpp::R_386_TLS_GD_PUSH
:
3366 case elfcpp::R_386_TLS_GD_CALL
:
3367 case elfcpp::R_386_TLS_GD_POP
:
3368 case elfcpp::R_386_TLS_LDM_32
:
3369 case elfcpp::R_386_TLS_LDM_PUSH
:
3370 case elfcpp::R_386_TLS_LDM_CALL
:
3371 case elfcpp::R_386_TLS_LDM_POP
:
3372 case elfcpp::R_386_USED_BY_INTEL_200
:
3374 object
->error(_("unsupported reloc %u in object file"), r_type
);
3379 // Scan the relocs during a relocatable link.
3382 Target_i386::scan_relocatable_relocs(Symbol_table
* symtab
,
3384 Sized_relobj_file
<32, false>* object
,
3385 unsigned int data_shndx
,
3386 unsigned int sh_type
,
3387 const unsigned char* prelocs
,
3389 Output_section
* output_section
,
3390 bool needs_special_offset_handling
,
3391 size_t local_symbol_count
,
3392 const unsigned char* plocal_symbols
,
3393 Relocatable_relocs
* rr
)
3395 gold_assert(sh_type
== elfcpp::SHT_REL
);
3397 typedef gold::Default_scan_relocatable_relocs
<elfcpp::SHT_REL
,
3398 Relocatable_size_for_reloc
> Scan_relocatable_relocs
;
3400 gold::scan_relocatable_relocs
<32, false, elfcpp::SHT_REL
,
3401 Scan_relocatable_relocs
>(
3409 needs_special_offset_handling
,
3415 // Relocate a section during a relocatable link.
3418 Target_i386::relocate_for_relocatable(
3419 const Relocate_info
<32, false>* relinfo
,
3420 unsigned int sh_type
,
3421 const unsigned char* prelocs
,
3423 Output_section
* output_section
,
3424 off_t offset_in_output_section
,
3425 const Relocatable_relocs
* rr
,
3426 unsigned char* view
,
3427 elfcpp::Elf_types
<32>::Elf_Addr view_address
,
3428 section_size_type view_size
,
3429 unsigned char* reloc_view
,
3430 section_size_type reloc_view_size
)
3432 gold_assert(sh_type
== elfcpp::SHT_REL
);
3434 gold::relocate_for_relocatable
<32, false, elfcpp::SHT_REL
>(
3439 offset_in_output_section
,
3448 // Return the value to use for a dynamic which requires special
3449 // treatment. This is how we support equality comparisons of function
3450 // pointers across shared library boundaries, as described in the
3451 // processor specific ABI supplement.
3454 Target_i386::do_dynsym_value(const Symbol
* gsym
) const
3456 gold_assert(gsym
->is_from_dynobj() && gsym
->has_plt_offset());
3457 return this->plt_address_for_global(gsym
) + gsym
->plt_offset();
3460 // Return a string used to fill a code section with nops to take up
3461 // the specified length.
3464 Target_i386::do_code_fill(section_size_type length
) const
3468 // Build a jmp instruction to skip over the bytes.
3469 unsigned char jmp
[5];
3471 elfcpp::Swap_unaligned
<32, false>::writeval(jmp
+ 1, length
- 5);
3472 return (std::string(reinterpret_cast<char*>(&jmp
[0]), 5)
3473 + std::string(length
- 5, '\0'));
3476 // Nop sequences of various lengths.
3477 const char nop1
[1] = { '\x90' }; // nop
3478 const char nop2
[2] = { '\x66', '\x90' }; // xchg %ax %ax
3479 const char nop3
[3] = { '\x8d', '\x76', '\x00' }; // leal 0(%esi),%esi
3480 const char nop4
[4] = { '\x8d', '\x74', '\x26', // leal 0(%esi,1),%esi
3482 const char nop5
[5] = { '\x90', '\x8d', '\x74', // nop
3483 '\x26', '\x00' }; // leal 0(%esi,1),%esi
3484 const char nop6
[6] = { '\x8d', '\xb6', '\x00', // leal 0L(%esi),%esi
3485 '\x00', '\x00', '\x00' };
3486 const char nop7
[7] = { '\x8d', '\xb4', '\x26', // leal 0L(%esi,1),%esi
3487 '\x00', '\x00', '\x00',
3489 const char nop8
[8] = { '\x90', '\x8d', '\xb4', // nop
3490 '\x26', '\x00', '\x00', // leal 0L(%esi,1),%esi
3492 const char nop9
[9] = { '\x89', '\xf6', '\x8d', // movl %esi,%esi
3493 '\xbc', '\x27', '\x00', // leal 0L(%edi,1),%edi
3494 '\x00', '\x00', '\x00' };
3495 const char nop10
[10] = { '\x8d', '\x76', '\x00', // leal 0(%esi),%esi
3496 '\x8d', '\xbc', '\x27', // leal 0L(%edi,1),%edi
3497 '\x00', '\x00', '\x00',
3499 const char nop11
[11] = { '\x8d', '\x74', '\x26', // leal 0(%esi,1),%esi
3500 '\x00', '\x8d', '\xbc', // leal 0L(%edi,1),%edi
3501 '\x27', '\x00', '\x00',
3503 const char nop12
[12] = { '\x8d', '\xb6', '\x00', // leal 0L(%esi),%esi
3504 '\x00', '\x00', '\x00', // leal 0L(%edi),%edi
3505 '\x8d', '\xbf', '\x00',
3506 '\x00', '\x00', '\x00' };
3507 const char nop13
[13] = { '\x8d', '\xb6', '\x00', // leal 0L(%esi),%esi
3508 '\x00', '\x00', '\x00', // leal 0L(%edi,1),%edi
3509 '\x8d', '\xbc', '\x27',
3510 '\x00', '\x00', '\x00',
3512 const char nop14
[14] = { '\x8d', '\xb4', '\x26', // leal 0L(%esi,1),%esi
3513 '\x00', '\x00', '\x00', // leal 0L(%edi,1),%edi
3514 '\x00', '\x8d', '\xbc',
3515 '\x27', '\x00', '\x00',
3517 const char nop15
[15] = { '\xeb', '\x0d', '\x90', // jmp .+15
3518 '\x90', '\x90', '\x90', // nop,nop,nop,...
3519 '\x90', '\x90', '\x90',
3520 '\x90', '\x90', '\x90',
3521 '\x90', '\x90', '\x90' };
3523 const char* nops
[16] = {
3525 nop1
, nop2
, nop3
, nop4
, nop5
, nop6
, nop7
,
3526 nop8
, nop9
, nop10
, nop11
, nop12
, nop13
, nop14
, nop15
3529 return std::string(nops
[length
], length
);
3532 // Return the value to use for the base of a DW_EH_PE_datarel offset
3533 // in an FDE. Solaris and SVR4 use DW_EH_PE_datarel because their
3534 // assembler can not write out the difference between two labels in
3535 // different sections, so instead of using a pc-relative value they
3536 // use an offset from the GOT.
3539 Target_i386::do_ehframe_datarel_base() const
3541 gold_assert(this->global_offset_table_
!= NULL
);
3542 Symbol
* sym
= this->global_offset_table_
;
3543 Sized_symbol
<32>* ssym
= static_cast<Sized_symbol
<32>*>(sym
);
3544 return ssym
->value();
3547 // Return whether SYM should be treated as a call to a non-split
3548 // function. We don't want that to be true of a call to a
3549 // get_pc_thunk function.
3552 Target_i386::do_is_call_to_non_split(const Symbol
* sym
, unsigned int) const
3554 return (sym
->type() == elfcpp::STT_FUNC
3555 && !is_prefix_of("__i686.get_pc_thunk.", sym
->name()));
3558 // FNOFFSET in section SHNDX in OBJECT is the start of a function
3559 // compiled with -fsplit-stack. The function calls non-split-stack
3560 // code. We have to change the function so that it always ensures
3561 // that it has enough stack space to run some random function.
3564 Target_i386::do_calls_non_split(Relobj
* object
, unsigned int shndx
,
3565 section_offset_type fnoffset
,
3566 section_size_type fnsize
,
3567 unsigned char* view
,
3568 section_size_type view_size
,
3570 std::string
* to
) const
3572 // The function starts with a comparison of the stack pointer and a
3573 // field in the TCB. This is followed by a jump.
3576 if (this->match_view(view
, view_size
, fnoffset
, "\x65\x3b\x25", 3)
3579 // We will call __morestack if the carry flag is set after this
3580 // comparison. We turn the comparison into an stc instruction
3582 view
[fnoffset
] = '\xf9';
3583 this->set_view_to_nop(view
, view_size
, fnoffset
+ 1, 6);
3585 // lea NN(%esp),%ecx
3586 // lea NN(%esp),%edx
3587 else if ((this->match_view(view
, view_size
, fnoffset
, "\x8d\x8c\x24", 3)
3588 || this->match_view(view
, view_size
, fnoffset
, "\x8d\x94\x24", 3))
3591 // This is loading an offset from the stack pointer for a
3592 // comparison. The offset is negative, so we decrease the
3593 // offset by the amount of space we need for the stack. This
3594 // means we will avoid calling __morestack if there happens to
3595 // be plenty of space on the stack already.
3596 unsigned char* pval
= view
+ fnoffset
+ 3;
3597 uint32_t val
= elfcpp::Swap_unaligned
<32, false>::readval(pval
);
3598 val
-= parameters
->options().split_stack_adjust_size();
3599 elfcpp::Swap_unaligned
<32, false>::writeval(pval
, val
);
3603 if (!object
->has_no_split_stack())
3604 object
->error(_("failed to match split-stack sequence at "
3605 "section %u offset %0zx"),
3606 shndx
, static_cast<size_t>(fnoffset
));
3610 // We have to change the function so that it calls
3611 // __morestack_non_split instead of __morestack. The former will
3612 // allocate additional stack space.
3613 *from
= "__morestack";
3614 *to
= "__morestack_non_split";
3617 // The selector for i386 object files.
3619 class Target_selector_i386
: public Target_selector_freebsd
3622 Target_selector_i386()
3623 : Target_selector_freebsd(elfcpp::EM_386
, 32, false,
3624 "elf32-i386", "elf32-i386-freebsd",
3629 do_instantiate_target()
3630 { return new Target_i386(); }
3633 Target_selector_i386 target_selector_i386
;
3635 } // End anonymous namespace.