1 // i386.cc -- i386 target support for gold.
3 // Copyright 2006, 2007, 2008, 2009 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.
28 #include "parameters.h"
35 #include "copy-relocs.h"
37 #include "target-reloc.h"
38 #include "target-select.h"
47 class Output_data_plt_i386
;
49 // The i386 target class.
50 // TLS info comes from
51 // http://people.redhat.com/drepper/tls.pdf
52 // http://www.lsd.ic.unicamp.br/~oliva/writeups/TLS/RFC-TLSDESC-x86.txt
54 class Target_i386
: public Target_freebsd
<32, false>
57 typedef Output_data_reloc
<elfcpp::SHT_REL
, true, 32, false> Reloc_section
;
60 : Target_freebsd
<32, false>(&i386_info
),
61 got_(NULL
), plt_(NULL
), got_plt_(NULL
), rel_dyn_(NULL
),
62 copy_relocs_(elfcpp::R_386_COPY
), dynbss_(NULL
),
63 got_mod_index_offset_(-1U), tls_base_symbol_defined_(false)
66 // Process the relocations to determine unreferenced sections for
67 // garbage collection.
69 gc_process_relocs(const General_options
& options
,
72 Sized_relobj
<32, false>* object
,
73 unsigned int data_shndx
,
75 const unsigned char* prelocs
,
77 Output_section
* output_section
,
78 bool needs_special_offset_handling
,
79 size_t local_symbol_count
,
80 const unsigned char* plocal_symbols
);
82 // Scan the relocations to look for symbol adjustments.
84 scan_relocs(const General_options
& options
,
87 Sized_relobj
<32, false>* object
,
88 unsigned int data_shndx
,
90 const unsigned char* prelocs
,
92 Output_section
* output_section
,
93 bool needs_special_offset_handling
,
94 size_t local_symbol_count
,
95 const unsigned char* plocal_symbols
);
97 // Finalize the sections.
99 do_finalize_sections(Layout
*);
101 // Return the value to use for a dynamic which requires special
104 do_dynsym_value(const Symbol
*) const;
106 // Relocate a section.
108 relocate_section(const Relocate_info
<32, false>*,
109 unsigned int sh_type
,
110 const unsigned char* prelocs
,
112 Output_section
* output_section
,
113 bool needs_special_offset_handling
,
115 elfcpp::Elf_types
<32>::Elf_Addr view_address
,
116 section_size_type view_size
);
118 // Scan the relocs during a relocatable link.
120 scan_relocatable_relocs(const General_options
& options
,
121 Symbol_table
* symtab
,
123 Sized_relobj
<32, false>* object
,
124 unsigned int data_shndx
,
125 unsigned int sh_type
,
126 const unsigned char* prelocs
,
128 Output_section
* output_section
,
129 bool needs_special_offset_handling
,
130 size_t local_symbol_count
,
131 const unsigned char* plocal_symbols
,
132 Relocatable_relocs
*);
134 // Relocate a section during a relocatable link.
136 relocate_for_relocatable(const Relocate_info
<32, false>*,
137 unsigned int sh_type
,
138 const unsigned char* prelocs
,
140 Output_section
* output_section
,
141 off_t offset_in_output_section
,
142 const Relocatable_relocs
*,
144 elfcpp::Elf_types
<32>::Elf_Addr view_address
,
145 section_size_type view_size
,
146 unsigned char* reloc_view
,
147 section_size_type reloc_view_size
);
149 // Return a string used to fill a code section with nops.
151 do_code_fill(section_size_type length
) const;
153 // Return whether SYM is defined by the ABI.
155 do_is_defined_by_abi(const Symbol
* sym
) const
156 { return strcmp(sym
->name(), "___tls_get_addr") == 0; }
158 // Return whether a symbol name implies a local label. The UnixWare
159 // 2.1 cc generates temporary symbols that start with .X, so we
160 // recognize them here. FIXME: do other SVR4 compilers also use .X?.
161 // If so, we should move the .X recognition into
162 // Target::do_is_local_label_name.
164 do_is_local_label_name(const char* name
) const
166 if (name
[0] == '.' && name
[1] == 'X')
168 return Target::do_is_local_label_name(name
);
171 // Return the size of the GOT section.
175 gold_assert(this->got_
!= NULL
);
176 return this->got_
->data_size();
180 // The class which scans relocations.
184 local(const General_options
& options
, Symbol_table
* symtab
,
185 Layout
* layout
, Target_i386
* target
,
186 Sized_relobj
<32, false>* object
,
187 unsigned int data_shndx
,
188 Output_section
* output_section
,
189 const elfcpp::Rel
<32, false>& reloc
, unsigned int r_type
,
190 const elfcpp::Sym
<32, false>& lsym
);
193 global(const General_options
& options
, Symbol_table
* symtab
,
194 Layout
* layout
, Target_i386
* target
,
195 Sized_relobj
<32, false>* object
,
196 unsigned int data_shndx
,
197 Output_section
* output_section
,
198 const elfcpp::Rel
<32, false>& reloc
, unsigned int r_type
,
202 unsupported_reloc_local(Sized_relobj
<32, false>*, unsigned int r_type
);
205 unsupported_reloc_global(Sized_relobj
<32, false>*, unsigned int r_type
,
209 // The class which implements relocation.
214 : skip_call_tls_get_addr_(false),
215 local_dynamic_type_(LOCAL_DYNAMIC_NONE
)
220 if (this->skip_call_tls_get_addr_
)
222 // FIXME: This needs to specify the location somehow.
223 gold_error(_("missing expected TLS relocation"));
227 // Return whether the static relocation needs to be applied.
229 should_apply_static_reloc(const Sized_symbol
<32>* gsym
,
232 Output_section
* output_section
);
234 // Do a relocation. Return false if the caller should not issue
235 // any warnings about this relocation.
237 relocate(const Relocate_info
<32, false>*, Target_i386
*, Output_section
*,
238 size_t relnum
, const elfcpp::Rel
<32, false>&,
239 unsigned int r_type
, const Sized_symbol
<32>*,
240 const Symbol_value
<32>*,
241 unsigned char*, elfcpp::Elf_types
<32>::Elf_Addr
,
245 // Do a TLS relocation.
247 relocate_tls(const Relocate_info
<32, false>*, Target_i386
* target
,
248 size_t relnum
, const elfcpp::Rel
<32, false>&,
249 unsigned int r_type
, const Sized_symbol
<32>*,
250 const Symbol_value
<32>*,
251 unsigned char*, elfcpp::Elf_types
<32>::Elf_Addr
,
254 // Do a TLS General-Dynamic to Initial-Exec transition.
256 tls_gd_to_ie(const Relocate_info
<32, false>*, size_t relnum
,
257 Output_segment
* tls_segment
,
258 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
259 elfcpp::Elf_types
<32>::Elf_Addr value
,
261 section_size_type view_size
);
263 // Do a TLS General-Dynamic to Local-Exec transition.
265 tls_gd_to_le(const Relocate_info
<32, false>*, size_t relnum
,
266 Output_segment
* tls_segment
,
267 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
268 elfcpp::Elf_types
<32>::Elf_Addr value
,
270 section_size_type view_size
);
272 // Do a TLS_GOTDESC or TLS_DESC_CALL General-Dynamic to Initial-Exec
275 tls_desc_gd_to_ie(const Relocate_info
<32, false>*, size_t relnum
,
276 Output_segment
* tls_segment
,
277 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
278 elfcpp::Elf_types
<32>::Elf_Addr value
,
280 section_size_type view_size
);
282 // Do a TLS_GOTDESC or TLS_DESC_CALL General-Dynamic to Local-Exec
285 tls_desc_gd_to_le(const Relocate_info
<32, false>*, size_t relnum
,
286 Output_segment
* tls_segment
,
287 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
288 elfcpp::Elf_types
<32>::Elf_Addr value
,
290 section_size_type view_size
);
292 // Do a TLS Local-Dynamic to Local-Exec transition.
294 tls_ld_to_le(const Relocate_info
<32, false>*, size_t relnum
,
295 Output_segment
* tls_segment
,
296 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
297 elfcpp::Elf_types
<32>::Elf_Addr value
,
299 section_size_type view_size
);
301 // Do a TLS Initial-Exec to Local-Exec transition.
303 tls_ie_to_le(const Relocate_info
<32, false>*, size_t relnum
,
304 Output_segment
* tls_segment
,
305 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
306 elfcpp::Elf_types
<32>::Elf_Addr value
,
308 section_size_type view_size
);
310 // We need to keep track of which type of local dynamic relocation
311 // we have seen, so that we can optimize R_386_TLS_LDO_32 correctly.
312 enum Local_dynamic_type
319 // This is set if we should skip the next reloc, which should be a
320 // PLT32 reloc against ___tls_get_addr.
321 bool skip_call_tls_get_addr_
;
322 // The type of local dynamic relocation we have seen in the section
323 // being relocated, if any.
324 Local_dynamic_type local_dynamic_type_
;
327 // A class which returns the size required for a relocation type,
328 // used while scanning relocs during a relocatable link.
329 class Relocatable_size_for_reloc
333 get_size_for_reloc(unsigned int, Relobj
*);
336 // Adjust TLS relocation type based on the options and whether this
337 // is a local symbol.
338 static tls::Tls_optimization
339 optimize_tls_reloc(bool is_final
, int r_type
);
341 // Get the GOT section, creating it if necessary.
342 Output_data_got
<32, false>*
343 got_section(Symbol_table
*, Layout
*);
345 // Get the GOT PLT section.
347 got_plt_section() const
349 gold_assert(this->got_plt_
!= NULL
);
350 return this->got_plt_
;
353 // Create a PLT entry for a global symbol.
355 make_plt_entry(Symbol_table
*, Layout
*, Symbol
*);
357 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
359 define_tls_base_symbol(Symbol_table
*, Layout
*);
361 // Create a GOT entry for the TLS module index.
363 got_mod_index_entry(Symbol_table
* symtab
, Layout
* layout
,
364 Sized_relobj
<32, false>* object
);
366 // Get the PLT section.
367 const Output_data_plt_i386
*
370 gold_assert(this->plt_
!= NULL
);
374 // Get the dynamic reloc section, creating it if necessary.
376 rel_dyn_section(Layout
*);
378 // Return true if the symbol may need a COPY relocation.
379 // References from an executable object to non-function symbols
380 // defined in a dynamic object may need a COPY relocation.
382 may_need_copy_reloc(Symbol
* gsym
)
384 return (!parameters
->options().shared()
385 && gsym
->is_from_dynobj()
386 && gsym
->type() != elfcpp::STT_FUNC
);
389 // Add a potential copy relocation.
391 copy_reloc(Symbol_table
* symtab
, Layout
* layout
,
392 Sized_relobj
<32, false>* object
,
393 unsigned int shndx
, Output_section
* output_section
,
394 Symbol
* sym
, const elfcpp::Rel
<32, false>& reloc
)
396 this->copy_relocs_
.copy_reloc(symtab
, layout
,
397 symtab
->get_sized_symbol
<32>(sym
),
398 object
, shndx
, output_section
, reloc
,
399 this->rel_dyn_section(layout
));
402 // Information about this specific target which we pass to the
403 // general Target structure.
404 static const Target::Target_info i386_info
;
406 // The types of GOT entries needed for this platform.
409 GOT_TYPE_STANDARD
= 0, // GOT entry for a regular symbol
410 GOT_TYPE_TLS_NOFFSET
= 1, // GOT entry for negative TLS offset
411 GOT_TYPE_TLS_OFFSET
= 2, // GOT entry for positive TLS offset
412 GOT_TYPE_TLS_PAIR
= 3, // GOT entry for TLS module/offset pair
413 GOT_TYPE_TLS_DESC
= 4 // GOT entry for TLS_DESC pair
417 Output_data_got
<32, false>* got_
;
419 Output_data_plt_i386
* plt_
;
420 // The GOT PLT section.
421 Output_data_space
* got_plt_
;
422 // The dynamic reloc section.
423 Reloc_section
* rel_dyn_
;
424 // Relocs saved to avoid a COPY reloc.
425 Copy_relocs
<elfcpp::SHT_REL
, 32, false> copy_relocs_
;
426 // Space for variables copied with a COPY reloc.
427 Output_data_space
* dynbss_
;
428 // Offset of the GOT entry for the TLS module index.
429 unsigned int got_mod_index_offset_
;
430 // True if the _TLS_MODULE_BASE_ symbol has been defined.
431 bool tls_base_symbol_defined_
;
434 const Target::Target_info
Target_i386::i386_info
=
437 false, // is_big_endian
438 elfcpp::EM_386
, // machine_code
439 false, // has_make_symbol
440 false, // has_resolve
441 true, // has_code_fill
442 true, // is_default_stack_executable
444 "/usr/lib/libc.so.1", // dynamic_linker
445 0x08048000, // default_text_segment_address
446 0x1000, // abi_pagesize (overridable by -z max-page-size)
447 0x1000 // common_pagesize (overridable by -z common-page-size)
450 // Get the GOT section, creating it if necessary.
452 Output_data_got
<32, false>*
453 Target_i386::got_section(Symbol_table
* symtab
, Layout
* layout
)
455 if (this->got_
== NULL
)
457 gold_assert(symtab
!= NULL
&& layout
!= NULL
);
459 this->got_
= new Output_data_got
<32, false>();
462 os
= layout
->add_output_section_data(".got", elfcpp::SHT_PROGBITS
,
464 | elfcpp::SHF_WRITE
),
468 // The old GNU linker creates a .got.plt section. We just
469 // create another set of data in the .got section. Note that we
470 // always create a PLT if we create a GOT, although the PLT
472 this->got_plt_
= new Output_data_space(4, "** GOT PLT");
473 os
= layout
->add_output_section_data(".got", elfcpp::SHT_PROGBITS
,
475 | elfcpp::SHF_WRITE
),
479 // The first three entries are reserved.
480 this->got_plt_
->set_current_data_size(3 * 4);
482 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
483 symtab
->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL
,
485 0, 0, elfcpp::STT_OBJECT
,
487 elfcpp::STV_HIDDEN
, 0,
494 // Get the dynamic reloc section, creating it if necessary.
496 Target_i386::Reloc_section
*
497 Target_i386::rel_dyn_section(Layout
* layout
)
499 if (this->rel_dyn_
== NULL
)
501 gold_assert(layout
!= NULL
);
502 this->rel_dyn_
= new Reloc_section(parameters
->options().combreloc());
503 layout
->add_output_section_data(".rel.dyn", elfcpp::SHT_REL
,
504 elfcpp::SHF_ALLOC
, this->rel_dyn_
);
506 return this->rel_dyn_
;
509 // A class to handle the PLT data.
511 class Output_data_plt_i386
: public Output_section_data
514 typedef Output_data_reloc
<elfcpp::SHT_REL
, true, 32, false> Reloc_section
;
516 Output_data_plt_i386(Layout
*, Output_data_space
*);
518 // Add an entry to the PLT.
520 add_entry(Symbol
* gsym
);
522 // Return the .rel.plt section data.
525 { return this->rel_
; }
529 do_adjust_output_section(Output_section
* os
);
531 // Write to a map file.
533 do_print_to_mapfile(Mapfile
* mapfile
) const
534 { mapfile
->print_output_data(this, _("** PLT")); }
537 // The size of an entry in the PLT.
538 static const int plt_entry_size
= 16;
540 // The first entry in the PLT for an executable.
541 static unsigned char exec_first_plt_entry
[plt_entry_size
];
543 // The first entry in the PLT for a shared object.
544 static unsigned char dyn_first_plt_entry
[plt_entry_size
];
546 // Other entries in the PLT for an executable.
547 static unsigned char exec_plt_entry
[plt_entry_size
];
549 // Other entries in the PLT for a shared object.
550 static unsigned char dyn_plt_entry
[plt_entry_size
];
552 // Set the final size.
554 set_final_data_size()
555 { this->set_data_size((this->count_
+ 1) * plt_entry_size
); }
557 // Write out the PLT data.
559 do_write(Output_file
*);
561 // The reloc section.
563 // The .got.plt section.
564 Output_data_space
* got_plt_
;
565 // The number of PLT entries.
569 // Create the PLT section. The ordinary .got section is an argument,
570 // since we need to refer to the start. We also create our own .got
571 // section just for PLT entries.
573 Output_data_plt_i386::Output_data_plt_i386(Layout
* layout
,
574 Output_data_space
* got_plt
)
575 : Output_section_data(4), got_plt_(got_plt
), count_(0)
577 this->rel_
= new Reloc_section(false);
578 layout
->add_output_section_data(".rel.plt", elfcpp::SHT_REL
,
579 elfcpp::SHF_ALLOC
, this->rel_
);
583 Output_data_plt_i386::do_adjust_output_section(Output_section
* os
)
585 // UnixWare sets the entsize of .plt to 4, and so does the old GNU
586 // linker, and so do we.
590 // Add an entry to the PLT.
593 Output_data_plt_i386::add_entry(Symbol
* gsym
)
595 gold_assert(!gsym
->has_plt_offset());
597 // Note that when setting the PLT offset we skip the initial
598 // reserved PLT entry.
599 gsym
->set_plt_offset((this->count_
+ 1) * plt_entry_size
);
603 section_offset_type got_offset
= this->got_plt_
->current_data_size();
605 // Every PLT entry needs a GOT entry which points back to the PLT
606 // entry (this will be changed by the dynamic linker, normally
607 // lazily when the function is called).
608 this->got_plt_
->set_current_data_size(got_offset
+ 4);
610 // Every PLT entry needs a reloc.
611 gsym
->set_needs_dynsym_entry();
612 this->rel_
->add_global(gsym
, elfcpp::R_386_JUMP_SLOT
, this->got_plt_
,
615 // Note that we don't need to save the symbol. The contents of the
616 // PLT are independent of which symbols are used. The symbols only
617 // appear in the relocations.
620 // The first entry in the PLT for an executable.
622 unsigned char Output_data_plt_i386::exec_first_plt_entry
[plt_entry_size
] =
624 0xff, 0x35, // pushl contents of memory address
625 0, 0, 0, 0, // replaced with address of .got + 4
626 0xff, 0x25, // jmp indirect
627 0, 0, 0, 0, // replaced with address of .got + 8
631 // The first entry in the PLT for a shared object.
633 unsigned char Output_data_plt_i386::dyn_first_plt_entry
[plt_entry_size
] =
635 0xff, 0xb3, 4, 0, 0, 0, // pushl 4(%ebx)
636 0xff, 0xa3, 8, 0, 0, 0, // jmp *8(%ebx)
640 // Subsequent entries in the PLT for an executable.
642 unsigned char Output_data_plt_i386::exec_plt_entry
[plt_entry_size
] =
644 0xff, 0x25, // jmp indirect
645 0, 0, 0, 0, // replaced with address of symbol in .got
646 0x68, // pushl immediate
647 0, 0, 0, 0, // replaced with offset into relocation table
648 0xe9, // jmp relative
649 0, 0, 0, 0 // replaced with offset to start of .plt
652 // Subsequent entries in the PLT for a shared object.
654 unsigned char Output_data_plt_i386::dyn_plt_entry
[plt_entry_size
] =
656 0xff, 0xa3, // jmp *offset(%ebx)
657 0, 0, 0, 0, // replaced with offset of symbol in .got
658 0x68, // pushl immediate
659 0, 0, 0, 0, // replaced with offset into relocation table
660 0xe9, // jmp relative
661 0, 0, 0, 0 // replaced with offset to start of .plt
664 // Write out the PLT. This uses the hand-coded instructions above,
665 // and adjusts them as needed. This is all specified by the i386 ELF
666 // Processor Supplement.
669 Output_data_plt_i386::do_write(Output_file
* of
)
671 const off_t offset
= this->offset();
672 const section_size_type oview_size
=
673 convert_to_section_size_type(this->data_size());
674 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
676 const off_t got_file_offset
= this->got_plt_
->offset();
677 const section_size_type got_size
=
678 convert_to_section_size_type(this->got_plt_
->data_size());
679 unsigned char* const got_view
= of
->get_output_view(got_file_offset
,
682 unsigned char* pov
= oview
;
684 elfcpp::Elf_types
<32>::Elf_Addr plt_address
= this->address();
685 elfcpp::Elf_types
<32>::Elf_Addr got_address
= this->got_plt_
->address();
687 if (parameters
->options().shared())
688 memcpy(pov
, dyn_first_plt_entry
, plt_entry_size
);
691 memcpy(pov
, exec_first_plt_entry
, plt_entry_size
);
692 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2, got_address
+ 4);
693 elfcpp::Swap
<32, false>::writeval(pov
+ 8, got_address
+ 8);
695 pov
+= plt_entry_size
;
697 unsigned char* got_pov
= got_view
;
699 memset(got_pov
, 0, 12);
702 const int rel_size
= elfcpp::Elf_sizes
<32>::rel_size
;
704 unsigned int plt_offset
= plt_entry_size
;
705 unsigned int plt_rel_offset
= 0;
706 unsigned int got_offset
= 12;
707 const unsigned int count
= this->count_
;
708 for (unsigned int i
= 0;
711 pov
+= plt_entry_size
,
713 plt_offset
+= plt_entry_size
,
714 plt_rel_offset
+= rel_size
,
717 // Set and adjust the PLT entry itself.
719 if (parameters
->options().shared())
721 memcpy(pov
, dyn_plt_entry
, plt_entry_size
);
722 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2, got_offset
);
726 memcpy(pov
, exec_plt_entry
, plt_entry_size
);
727 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
732 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 7, plt_rel_offset
);
733 elfcpp::Swap
<32, false>::writeval(pov
+ 12,
734 - (plt_offset
+ plt_entry_size
));
736 // Set the entry in the GOT.
737 elfcpp::Swap
<32, false>::writeval(got_pov
, plt_address
+ plt_offset
+ 6);
740 gold_assert(static_cast<section_size_type
>(pov
- oview
) == oview_size
);
741 gold_assert(static_cast<section_size_type
>(got_pov
- got_view
) == got_size
);
743 of
->write_output_view(offset
, oview_size
, oview
);
744 of
->write_output_view(got_file_offset
, got_size
, got_view
);
747 // Create a PLT entry for a global symbol.
750 Target_i386::make_plt_entry(Symbol_table
* symtab
, Layout
* layout
, Symbol
* gsym
)
752 if (gsym
->has_plt_offset())
755 if (this->plt_
== NULL
)
757 // Create the GOT sections first.
758 this->got_section(symtab
, layout
);
760 this->plt_
= new Output_data_plt_i386(layout
, this->got_plt_
);
761 layout
->add_output_section_data(".plt", elfcpp::SHT_PROGBITS
,
763 | elfcpp::SHF_EXECINSTR
),
767 this->plt_
->add_entry(gsym
);
770 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
773 Target_i386::define_tls_base_symbol(Symbol_table
* symtab
, Layout
* layout
)
775 if (this->tls_base_symbol_defined_
)
778 Output_segment
* tls_segment
= layout
->tls_segment();
779 if (tls_segment
!= NULL
)
781 bool is_exec
= parameters
->options().output_is_executable();
782 symtab
->define_in_output_segment("_TLS_MODULE_BASE_", NULL
,
786 elfcpp::STV_HIDDEN
, 0,
788 ? Symbol::SEGMENT_END
789 : Symbol::SEGMENT_START
),
792 this->tls_base_symbol_defined_
= true;
795 // Create a GOT entry for the TLS module index.
798 Target_i386::got_mod_index_entry(Symbol_table
* symtab
, Layout
* layout
,
799 Sized_relobj
<32, false>* object
)
801 if (this->got_mod_index_offset_
== -1U)
803 gold_assert(symtab
!= NULL
&& layout
!= NULL
&& object
!= NULL
);
804 Reloc_section
* rel_dyn
= this->rel_dyn_section(layout
);
805 Output_data_got
<32, false>* got
= this->got_section(symtab
, layout
);
806 unsigned int got_offset
= got
->add_constant(0);
807 rel_dyn
->add_local(object
, 0, elfcpp::R_386_TLS_DTPMOD32
, got
,
809 got
->add_constant(0);
810 this->got_mod_index_offset_
= got_offset
;
812 return this->got_mod_index_offset_
;
815 // Optimize the TLS relocation type based on what we know about the
816 // symbol. IS_FINAL is true if the final address of this symbol is
817 // known at link time.
819 tls::Tls_optimization
820 Target_i386::optimize_tls_reloc(bool is_final
, int r_type
)
822 // If we are generating a shared library, then we can't do anything
824 if (parameters
->options().shared())
825 return tls::TLSOPT_NONE
;
829 case elfcpp::R_386_TLS_GD
:
830 case elfcpp::R_386_TLS_GOTDESC
:
831 case elfcpp::R_386_TLS_DESC_CALL
:
832 // These are General-Dynamic which permits fully general TLS
833 // access. Since we know that we are generating an executable,
834 // we can convert this to Initial-Exec. If we also know that
835 // this is a local symbol, we can further switch to Local-Exec.
837 return tls::TLSOPT_TO_LE
;
838 return tls::TLSOPT_TO_IE
;
840 case elfcpp::R_386_TLS_LDM
:
841 // This is Local-Dynamic, which refers to a local symbol in the
842 // dynamic TLS block. Since we know that we generating an
843 // executable, we can switch to Local-Exec.
844 return tls::TLSOPT_TO_LE
;
846 case elfcpp::R_386_TLS_LDO_32
:
847 // Another type of Local-Dynamic relocation.
848 return tls::TLSOPT_TO_LE
;
850 case elfcpp::R_386_TLS_IE
:
851 case elfcpp::R_386_TLS_GOTIE
:
852 case elfcpp::R_386_TLS_IE_32
:
853 // These are Initial-Exec relocs which get the thread offset
854 // from the GOT. If we know that we are linking against the
855 // local symbol, we can switch to Local-Exec, which links the
856 // thread offset into the instruction.
858 return tls::TLSOPT_TO_LE
;
859 return tls::TLSOPT_NONE
;
861 case elfcpp::R_386_TLS_LE
:
862 case elfcpp::R_386_TLS_LE_32
:
863 // When we already have Local-Exec, there is nothing further we
865 return tls::TLSOPT_NONE
;
872 // Report an unsupported relocation against a local symbol.
875 Target_i386::Scan::unsupported_reloc_local(Sized_relobj
<32, false>* object
,
878 gold_error(_("%s: unsupported reloc %u against local symbol"),
879 object
->name().c_str(), r_type
);
882 // Scan a relocation for a local symbol.
885 Target_i386::Scan::local(const General_options
&,
886 Symbol_table
* symtab
,
889 Sized_relobj
<32, false>* object
,
890 unsigned int data_shndx
,
891 Output_section
* output_section
,
892 const elfcpp::Rel
<32, false>& reloc
,
894 const elfcpp::Sym
<32, false>& lsym
)
898 case elfcpp::R_386_NONE
:
899 case elfcpp::R_386_GNU_VTINHERIT
:
900 case elfcpp::R_386_GNU_VTENTRY
:
903 case elfcpp::R_386_32
:
904 // If building a shared library (or a position-independent
905 // executable), we need to create a dynamic relocation for
906 // this location. The relocation applied at link time will
907 // apply the link-time value, so we flag the location with
908 // an R_386_RELATIVE relocation so the dynamic loader can
909 // relocate it easily.
910 if (parameters
->options().output_is_position_independent())
912 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
913 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
914 rel_dyn
->add_local_relative(object
, r_sym
, elfcpp::R_386_RELATIVE
,
915 output_section
, data_shndx
,
916 reloc
.get_r_offset());
920 case elfcpp::R_386_16
:
921 case elfcpp::R_386_8
:
922 // If building a shared library (or a position-independent
923 // executable), we need to create a dynamic relocation for
924 // this location. Because the addend needs to remain in the
925 // data section, we need to be careful not to apply this
926 // relocation statically.
927 if (parameters
->options().output_is_position_independent())
929 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
930 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
931 if (lsym
.get_st_type() != elfcpp::STT_SECTION
)
932 rel_dyn
->add_local(object
, r_sym
, r_type
, output_section
,
933 data_shndx
, reloc
.get_r_offset());
936 gold_assert(lsym
.get_st_value() == 0);
937 unsigned int shndx
= lsym
.get_st_shndx();
939 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
,
942 object
->error(_("section symbol %u has bad shndx %u"),
945 rel_dyn
->add_local_section(object
, shndx
,
946 r_type
, output_section
,
947 data_shndx
, reloc
.get_r_offset());
952 case elfcpp::R_386_PC32
:
953 case elfcpp::R_386_PC16
:
954 case elfcpp::R_386_PC8
:
957 case elfcpp::R_386_PLT32
:
958 // Since we know this is a local symbol, we can handle this as a
962 case elfcpp::R_386_GOTOFF
:
963 case elfcpp::R_386_GOTPC
:
964 // We need a GOT section.
965 target
->got_section(symtab
, layout
);
968 case elfcpp::R_386_GOT32
:
970 // The symbol requires a GOT entry.
971 Output_data_got
<32, false>* got
= target
->got_section(symtab
, layout
);
972 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
973 if (got
->add_local(object
, r_sym
, GOT_TYPE_STANDARD
))
975 // If we are generating a shared object, we need to add a
976 // dynamic RELATIVE relocation for this symbol's GOT entry.
977 if (parameters
->options().output_is_position_independent())
979 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
980 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
981 rel_dyn
->add_local_relative(
982 object
, r_sym
, elfcpp::R_386_RELATIVE
, got
,
983 object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
));
989 // These are relocations which should only be seen by the
990 // dynamic linker, and should never be seen here.
991 case elfcpp::R_386_COPY
:
992 case elfcpp::R_386_GLOB_DAT
:
993 case elfcpp::R_386_JUMP_SLOT
:
994 case elfcpp::R_386_RELATIVE
:
995 case elfcpp::R_386_TLS_TPOFF
:
996 case elfcpp::R_386_TLS_DTPMOD32
:
997 case elfcpp::R_386_TLS_DTPOFF32
:
998 case elfcpp::R_386_TLS_TPOFF32
:
999 case elfcpp::R_386_TLS_DESC
:
1000 gold_error(_("%s: unexpected reloc %u in object file"),
1001 object
->name().c_str(), r_type
);
1004 // These are initial TLS relocs, which are expected when
1006 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1007 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
1008 case elfcpp::R_386_TLS_DESC_CALL
:
1009 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1010 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1011 case elfcpp::R_386_TLS_IE
: // Initial-exec
1012 case elfcpp::R_386_TLS_IE_32
:
1013 case elfcpp::R_386_TLS_GOTIE
:
1014 case elfcpp::R_386_TLS_LE
: // Local-exec
1015 case elfcpp::R_386_TLS_LE_32
:
1017 bool output_is_shared
= parameters
->options().shared();
1018 const tls::Tls_optimization optimized_type
1019 = Target_i386::optimize_tls_reloc(!output_is_shared
, r_type
);
1022 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1023 if (optimized_type
== tls::TLSOPT_NONE
)
1025 // Create a pair of GOT entries for the module index and
1026 // dtv-relative offset.
1027 Output_data_got
<32, false>* got
1028 = target
->got_section(symtab
, layout
);
1029 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1030 unsigned int shndx
= lsym
.get_st_shndx();
1032 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
, &is_ordinary
);
1034 object
->error(_("local symbol %u has bad shndx %u"),
1037 got
->add_local_pair_with_rel(object
, r_sym
, shndx
,
1039 target
->rel_dyn_section(layout
),
1040 elfcpp::R_386_TLS_DTPMOD32
, 0);
1042 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1043 unsupported_reloc_local(object
, r_type
);
1046 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva)
1047 target
->define_tls_base_symbol(symtab
, layout
);
1048 if (optimized_type
== tls::TLSOPT_NONE
)
1050 // Create a double GOT entry with an R_386_TLS_DESC reloc.
1051 Output_data_got
<32, false>* got
1052 = target
->got_section(symtab
, layout
);
1053 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1054 unsigned int shndx
= lsym
.get_st_shndx();
1056 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
, &is_ordinary
);
1058 object
->error(_("local symbol %u has bad shndx %u"),
1061 got
->add_local_pair_with_rel(object
, r_sym
, shndx
,
1063 target
->rel_dyn_section(layout
),
1064 elfcpp::R_386_TLS_DESC
, 0);
1066 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1067 unsupported_reloc_local(object
, r_type
);
1070 case elfcpp::R_386_TLS_DESC_CALL
:
1073 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1074 if (optimized_type
== tls::TLSOPT_NONE
)
1076 // Create a GOT entry for the module index.
1077 target
->got_mod_index_entry(symtab
, layout
, object
);
1079 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1080 unsupported_reloc_local(object
, r_type
);
1083 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1086 case elfcpp::R_386_TLS_IE
: // Initial-exec
1087 case elfcpp::R_386_TLS_IE_32
:
1088 case elfcpp::R_386_TLS_GOTIE
:
1089 layout
->set_has_static_tls();
1090 if (optimized_type
== tls::TLSOPT_NONE
)
1092 // For the R_386_TLS_IE relocation, we need to create a
1093 // dynamic relocation when building a shared library.
1094 if (r_type
== elfcpp::R_386_TLS_IE
1095 && parameters
->options().shared())
1097 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1099 = elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1100 rel_dyn
->add_local_relative(object
, r_sym
,
1101 elfcpp::R_386_RELATIVE
,
1102 output_section
, data_shndx
,
1103 reloc
.get_r_offset());
1105 // Create a GOT entry for the tp-relative offset.
1106 Output_data_got
<32, false>* got
1107 = target
->got_section(symtab
, layout
);
1108 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1109 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_IE_32
1110 ? elfcpp::R_386_TLS_TPOFF32
1111 : elfcpp::R_386_TLS_TPOFF
);
1112 unsigned int got_type
= (r_type
== elfcpp::R_386_TLS_IE_32
1113 ? GOT_TYPE_TLS_OFFSET
1114 : GOT_TYPE_TLS_NOFFSET
);
1115 got
->add_local_with_rel(object
, r_sym
, got_type
,
1116 target
->rel_dyn_section(layout
),
1119 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1120 unsupported_reloc_local(object
, r_type
);
1123 case elfcpp::R_386_TLS_LE
: // Local-exec
1124 case elfcpp::R_386_TLS_LE_32
:
1125 layout
->set_has_static_tls();
1126 if (output_is_shared
)
1128 // We need to create a dynamic relocation.
1129 gold_assert(lsym
.get_st_type() != elfcpp::STT_SECTION
);
1130 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1131 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_LE_32
1132 ? elfcpp::R_386_TLS_TPOFF32
1133 : elfcpp::R_386_TLS_TPOFF
);
1134 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1135 rel_dyn
->add_local(object
, r_sym
, dyn_r_type
, output_section
,
1136 data_shndx
, reloc
.get_r_offset());
1146 case elfcpp::R_386_32PLT
:
1147 case elfcpp::R_386_TLS_GD_32
:
1148 case elfcpp::R_386_TLS_GD_PUSH
:
1149 case elfcpp::R_386_TLS_GD_CALL
:
1150 case elfcpp::R_386_TLS_GD_POP
:
1151 case elfcpp::R_386_TLS_LDM_32
:
1152 case elfcpp::R_386_TLS_LDM_PUSH
:
1153 case elfcpp::R_386_TLS_LDM_CALL
:
1154 case elfcpp::R_386_TLS_LDM_POP
:
1155 case elfcpp::R_386_USED_BY_INTEL_200
:
1157 unsupported_reloc_local(object
, r_type
);
1162 // Report an unsupported relocation against a global symbol.
1165 Target_i386::Scan::unsupported_reloc_global(Sized_relobj
<32, false>* object
,
1166 unsigned int r_type
,
1169 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
1170 object
->name().c_str(), r_type
, gsym
->demangled_name().c_str());
1173 // Scan a relocation for a global symbol.
1176 Target_i386::Scan::global(const General_options
&,
1177 Symbol_table
* symtab
,
1179 Target_i386
* target
,
1180 Sized_relobj
<32, false>* object
,
1181 unsigned int data_shndx
,
1182 Output_section
* output_section
,
1183 const elfcpp::Rel
<32, false>& reloc
,
1184 unsigned int r_type
,
1189 case elfcpp::R_386_NONE
:
1190 case elfcpp::R_386_GNU_VTINHERIT
:
1191 case elfcpp::R_386_GNU_VTENTRY
:
1194 case elfcpp::R_386_32
:
1195 case elfcpp::R_386_16
:
1196 case elfcpp::R_386_8
:
1198 // Make a PLT entry if necessary.
1199 if (gsym
->needs_plt_entry())
1201 target
->make_plt_entry(symtab
, layout
, gsym
);
1202 // Since this is not a PC-relative relocation, we may be
1203 // taking the address of a function. In that case we need to
1204 // set the entry in the dynamic symbol table to the address of
1206 if (gsym
->is_from_dynobj() && !parameters
->options().shared())
1207 gsym
->set_needs_dynsym_value();
1209 // Make a dynamic relocation if necessary.
1210 if (gsym
->needs_dynamic_reloc(Symbol::ABSOLUTE_REF
))
1212 if (target
->may_need_copy_reloc(gsym
))
1214 target
->copy_reloc(symtab
, layout
, object
,
1215 data_shndx
, output_section
, gsym
, reloc
);
1217 else if (r_type
== elfcpp::R_386_32
1218 && gsym
->can_use_relative_reloc(false))
1220 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1221 rel_dyn
->add_global_relative(gsym
, elfcpp::R_386_RELATIVE
,
1222 output_section
, object
,
1223 data_shndx
, reloc
.get_r_offset());
1227 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1228 rel_dyn
->add_global(gsym
, r_type
, output_section
, object
,
1229 data_shndx
, reloc
.get_r_offset());
1235 case elfcpp::R_386_PC32
:
1236 case elfcpp::R_386_PC16
:
1237 case elfcpp::R_386_PC8
:
1239 // Make a PLT entry if necessary.
1240 if (gsym
->needs_plt_entry())
1242 // These relocations are used for function calls only in
1243 // non-PIC code. For a 32-bit relocation in a shared library,
1244 // we'll need a text relocation anyway, so we can skip the
1245 // PLT entry and let the dynamic linker bind the call directly
1246 // to the target. For smaller relocations, we should use a
1247 // PLT entry to ensure that the call can reach.
1248 if (!parameters
->options().shared()
1249 || r_type
!= elfcpp::R_386_PC32
)
1250 target
->make_plt_entry(symtab
, layout
, gsym
);
1252 // Make a dynamic relocation if necessary.
1253 int flags
= Symbol::NON_PIC_REF
;
1254 if (gsym
->type() == elfcpp::STT_FUNC
)
1255 flags
|= Symbol::FUNCTION_CALL
;
1256 if (gsym
->needs_dynamic_reloc(flags
))
1258 if (target
->may_need_copy_reloc(gsym
))
1260 target
->copy_reloc(symtab
, layout
, object
,
1261 data_shndx
, output_section
, gsym
, reloc
);
1265 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1266 rel_dyn
->add_global(gsym
, r_type
, output_section
, object
,
1267 data_shndx
, reloc
.get_r_offset());
1273 case elfcpp::R_386_GOT32
:
1275 // The symbol requires a GOT entry.
1276 Output_data_got
<32, false>* got
= target
->got_section(symtab
, layout
);
1277 if (gsym
->final_value_is_known())
1278 got
->add_global(gsym
, GOT_TYPE_STANDARD
);
1281 // If this symbol is not fully resolved, we need to add a
1282 // GOT entry with a dynamic relocation.
1283 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1284 if (gsym
->is_from_dynobj()
1285 || gsym
->is_undefined()
1286 || gsym
->is_preemptible())
1287 got
->add_global_with_rel(gsym
, GOT_TYPE_STANDARD
,
1288 rel_dyn
, elfcpp::R_386_GLOB_DAT
);
1291 if (got
->add_global(gsym
, GOT_TYPE_STANDARD
))
1292 rel_dyn
->add_global_relative(
1293 gsym
, elfcpp::R_386_RELATIVE
, got
,
1294 gsym
->got_offset(GOT_TYPE_STANDARD
));
1300 case elfcpp::R_386_PLT32
:
1301 // If the symbol is fully resolved, this is just a PC32 reloc.
1302 // Otherwise we need a PLT entry.
1303 if (gsym
->final_value_is_known())
1305 // If building a shared library, we can also skip the PLT entry
1306 // if the symbol is defined in the output file and is protected
1308 if (gsym
->is_defined()
1309 && !gsym
->is_from_dynobj()
1310 && !gsym
->is_preemptible())
1312 target
->make_plt_entry(symtab
, layout
, gsym
);
1315 case elfcpp::R_386_GOTOFF
:
1316 case elfcpp::R_386_GOTPC
:
1317 // We need a GOT section.
1318 target
->got_section(symtab
, layout
);
1321 // These are relocations which should only be seen by the
1322 // dynamic linker, and should never be seen here.
1323 case elfcpp::R_386_COPY
:
1324 case elfcpp::R_386_GLOB_DAT
:
1325 case elfcpp::R_386_JUMP_SLOT
:
1326 case elfcpp::R_386_RELATIVE
:
1327 case elfcpp::R_386_TLS_TPOFF
:
1328 case elfcpp::R_386_TLS_DTPMOD32
:
1329 case elfcpp::R_386_TLS_DTPOFF32
:
1330 case elfcpp::R_386_TLS_TPOFF32
:
1331 case elfcpp::R_386_TLS_DESC
:
1332 gold_error(_("%s: unexpected reloc %u in object file"),
1333 object
->name().c_str(), r_type
);
1336 // These are initial tls relocs, which are expected when
1338 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1339 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
1340 case elfcpp::R_386_TLS_DESC_CALL
:
1341 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1342 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1343 case elfcpp::R_386_TLS_IE
: // Initial-exec
1344 case elfcpp::R_386_TLS_IE_32
:
1345 case elfcpp::R_386_TLS_GOTIE
:
1346 case elfcpp::R_386_TLS_LE
: // Local-exec
1347 case elfcpp::R_386_TLS_LE_32
:
1349 const bool is_final
= gsym
->final_value_is_known();
1350 const tls::Tls_optimization optimized_type
1351 = Target_i386::optimize_tls_reloc(is_final
, r_type
);
1354 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1355 if (optimized_type
== tls::TLSOPT_NONE
)
1357 // Create a pair of GOT entries for the module index and
1358 // dtv-relative offset.
1359 Output_data_got
<32, false>* got
1360 = target
->got_section(symtab
, layout
);
1361 got
->add_global_pair_with_rel(gsym
, GOT_TYPE_TLS_PAIR
,
1362 target
->rel_dyn_section(layout
),
1363 elfcpp::R_386_TLS_DTPMOD32
,
1364 elfcpp::R_386_TLS_DTPOFF32
);
1366 else if (optimized_type
== tls::TLSOPT_TO_IE
)
1368 // Create a GOT entry for the tp-relative offset.
1369 Output_data_got
<32, false>* got
1370 = target
->got_section(symtab
, layout
);
1371 got
->add_global_with_rel(gsym
, GOT_TYPE_TLS_NOFFSET
,
1372 target
->rel_dyn_section(layout
),
1373 elfcpp::R_386_TLS_TPOFF
);
1375 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1376 unsupported_reloc_global(object
, r_type
, gsym
);
1379 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (~oliva url)
1380 target
->define_tls_base_symbol(symtab
, layout
);
1381 if (optimized_type
== tls::TLSOPT_NONE
)
1383 // Create a double GOT entry with an R_386_TLS_DESC reloc.
1384 Output_data_got
<32, false>* got
1385 = target
->got_section(symtab
, layout
);
1386 got
->add_global_pair_with_rel(gsym
, GOT_TYPE_TLS_DESC
,
1387 target
->rel_dyn_section(layout
),
1388 elfcpp::R_386_TLS_DESC
, 0);
1390 else if (optimized_type
== tls::TLSOPT_TO_IE
)
1392 // Create a GOT entry for the tp-relative offset.
1393 Output_data_got
<32, false>* got
1394 = target
->got_section(symtab
, layout
);
1395 got
->add_global_with_rel(gsym
, GOT_TYPE_TLS_NOFFSET
,
1396 target
->rel_dyn_section(layout
),
1397 elfcpp::R_386_TLS_TPOFF
);
1399 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1400 unsupported_reloc_global(object
, r_type
, gsym
);
1403 case elfcpp::R_386_TLS_DESC_CALL
:
1406 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1407 if (optimized_type
== tls::TLSOPT_NONE
)
1409 // Create a GOT entry for the module index.
1410 target
->got_mod_index_entry(symtab
, layout
, object
);
1412 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1413 unsupported_reloc_global(object
, r_type
, gsym
);
1416 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1419 case elfcpp::R_386_TLS_IE
: // Initial-exec
1420 case elfcpp::R_386_TLS_IE_32
:
1421 case elfcpp::R_386_TLS_GOTIE
:
1422 layout
->set_has_static_tls();
1423 if (optimized_type
== tls::TLSOPT_NONE
)
1425 // For the R_386_TLS_IE relocation, we need to create a
1426 // dynamic relocation when building a shared library.
1427 if (r_type
== elfcpp::R_386_TLS_IE
1428 && parameters
->options().shared())
1430 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1431 rel_dyn
->add_global_relative(gsym
, elfcpp::R_386_RELATIVE
,
1432 output_section
, object
,
1434 reloc
.get_r_offset());
1436 // Create a GOT entry for the tp-relative offset.
1437 Output_data_got
<32, false>* got
1438 = target
->got_section(symtab
, layout
);
1439 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_IE_32
1440 ? elfcpp::R_386_TLS_TPOFF32
1441 : elfcpp::R_386_TLS_TPOFF
);
1442 unsigned int got_type
= (r_type
== elfcpp::R_386_TLS_IE_32
1443 ? GOT_TYPE_TLS_OFFSET
1444 : GOT_TYPE_TLS_NOFFSET
);
1445 got
->add_global_with_rel(gsym
, got_type
,
1446 target
->rel_dyn_section(layout
),
1449 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1450 unsupported_reloc_global(object
, r_type
, gsym
);
1453 case elfcpp::R_386_TLS_LE
: // Local-exec
1454 case elfcpp::R_386_TLS_LE_32
:
1455 layout
->set_has_static_tls();
1456 if (parameters
->options().shared())
1458 // We need to create a dynamic relocation.
1459 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_LE_32
1460 ? elfcpp::R_386_TLS_TPOFF32
1461 : elfcpp::R_386_TLS_TPOFF
);
1462 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1463 rel_dyn
->add_global(gsym
, dyn_r_type
, output_section
, object
,
1464 data_shndx
, reloc
.get_r_offset());
1474 case elfcpp::R_386_32PLT
:
1475 case elfcpp::R_386_TLS_GD_32
:
1476 case elfcpp::R_386_TLS_GD_PUSH
:
1477 case elfcpp::R_386_TLS_GD_CALL
:
1478 case elfcpp::R_386_TLS_GD_POP
:
1479 case elfcpp::R_386_TLS_LDM_32
:
1480 case elfcpp::R_386_TLS_LDM_PUSH
:
1481 case elfcpp::R_386_TLS_LDM_CALL
:
1482 case elfcpp::R_386_TLS_LDM_POP
:
1483 case elfcpp::R_386_USED_BY_INTEL_200
:
1485 unsupported_reloc_global(object
, r_type
, gsym
);
1490 // Process relocations for gc.
1493 Target_i386::gc_process_relocs(const General_options
& options
,
1494 Symbol_table
* symtab
,
1496 Sized_relobj
<32, false>* object
,
1497 unsigned int data_shndx
,
1499 const unsigned char* prelocs
,
1501 Output_section
* output_section
,
1502 bool needs_special_offset_handling
,
1503 size_t local_symbol_count
,
1504 const unsigned char* plocal_symbols
)
1506 gold::gc_process_relocs
<32, false, Target_i386
, elfcpp::SHT_REL
,
1517 needs_special_offset_handling
,
1522 // Scan relocations for a section.
1525 Target_i386::scan_relocs(const General_options
& options
,
1526 Symbol_table
* symtab
,
1528 Sized_relobj
<32, false>* object
,
1529 unsigned int data_shndx
,
1530 unsigned int sh_type
,
1531 const unsigned char* prelocs
,
1533 Output_section
* output_section
,
1534 bool needs_special_offset_handling
,
1535 size_t local_symbol_count
,
1536 const unsigned char* plocal_symbols
)
1538 if (sh_type
== elfcpp::SHT_RELA
)
1540 gold_error(_("%s: unsupported RELA reloc section"),
1541 object
->name().c_str());
1545 gold::scan_relocs
<32, false, Target_i386
, elfcpp::SHT_REL
,
1556 needs_special_offset_handling
,
1561 // Finalize the sections.
1564 Target_i386::do_finalize_sections(Layout
* layout
)
1566 // Fill in some more dynamic tags.
1567 Output_data_dynamic
* const odyn
= layout
->dynamic_data();
1570 if (this->got_plt_
!= NULL
)
1571 odyn
->add_section_address(elfcpp::DT_PLTGOT
, this->got_plt_
);
1573 if (this->plt_
!= NULL
)
1575 const Output_data
* od
= this->plt_
->rel_plt();
1576 odyn
->add_section_size(elfcpp::DT_PLTRELSZ
, od
);
1577 odyn
->add_section_address(elfcpp::DT_JMPREL
, od
);
1578 odyn
->add_constant(elfcpp::DT_PLTREL
, elfcpp::DT_REL
);
1581 if (this->rel_dyn_
!= NULL
)
1583 const Output_data
* od
= this->rel_dyn_
;
1584 odyn
->add_section_address(elfcpp::DT_REL
, od
);
1585 odyn
->add_section_size(elfcpp::DT_RELSZ
, od
);
1586 odyn
->add_constant(elfcpp::DT_RELENT
,
1587 elfcpp::Elf_sizes
<32>::rel_size
);
1590 if (!parameters
->options().shared())
1592 // The value of the DT_DEBUG tag is filled in by the dynamic
1593 // linker at run time, and used by the debugger.
1594 odyn
->add_constant(elfcpp::DT_DEBUG
, 0);
1598 // Emit any relocs we saved in an attempt to avoid generating COPY
1600 if (this->copy_relocs_
.any_saved_relocs())
1601 this->copy_relocs_
.emit(this->rel_dyn_section(layout
));
1604 // Return whether a direct absolute static relocation needs to be applied.
1605 // In cases where Scan::local() or Scan::global() has created
1606 // a dynamic relocation other than R_386_RELATIVE, the addend
1607 // of the relocation is carried in the data, and we must not
1608 // apply the static relocation.
1611 Target_i386::Relocate::should_apply_static_reloc(const Sized_symbol
<32>* gsym
,
1614 Output_section
* output_section
)
1616 // If the output section is not allocated, then we didn't call
1617 // scan_relocs, we didn't create a dynamic reloc, and we must apply
1619 if ((output_section
->flags() & elfcpp::SHF_ALLOC
) == 0)
1622 // For local symbols, we will have created a non-RELATIVE dynamic
1623 // relocation only if (a) the output is position independent,
1624 // (b) the relocation is absolute (not pc- or segment-relative), and
1625 // (c) the relocation is not 32 bits wide.
1627 return !(parameters
->options().output_is_position_independent()
1628 && (ref_flags
& Symbol::ABSOLUTE_REF
)
1631 // For global symbols, we use the same helper routines used in the
1632 // scan pass. If we did not create a dynamic relocation, or if we
1633 // created a RELATIVE dynamic relocation, we should apply the static
1635 bool has_dyn
= gsym
->needs_dynamic_reloc(ref_flags
);
1636 bool is_rel
= (ref_flags
& Symbol::ABSOLUTE_REF
)
1637 && gsym
->can_use_relative_reloc(ref_flags
1638 & Symbol::FUNCTION_CALL
);
1639 return !has_dyn
|| is_rel
;
1642 // Perform a relocation.
1645 Target_i386::Relocate::relocate(const Relocate_info
<32, false>* relinfo
,
1646 Target_i386
* target
,
1647 Output_section
*output_section
,
1649 const elfcpp::Rel
<32, false>& rel
,
1650 unsigned int r_type
,
1651 const Sized_symbol
<32>* gsym
,
1652 const Symbol_value
<32>* psymval
,
1653 unsigned char* view
,
1654 elfcpp::Elf_types
<32>::Elf_Addr address
,
1655 section_size_type view_size
)
1657 if (this->skip_call_tls_get_addr_
)
1659 if ((r_type
!= elfcpp::R_386_PLT32
1660 && r_type
!= elfcpp::R_386_PC32
)
1662 || strcmp(gsym
->name(), "___tls_get_addr") != 0)
1663 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
1664 _("missing expected TLS relocation"));
1667 this->skip_call_tls_get_addr_
= false;
1672 // Pick the value to use for symbols defined in shared objects.
1673 Symbol_value
<32> symval
;
1675 && gsym
->use_plt_offset(r_type
== elfcpp::R_386_PC8
1676 || r_type
== elfcpp::R_386_PC16
1677 || r_type
== elfcpp::R_386_PC32
))
1679 symval
.set_output_value(target
->plt_section()->address()
1680 + gsym
->plt_offset());
1684 const Sized_relobj
<32, false>* object
= relinfo
->object
;
1686 // Get the GOT offset if needed.
1687 // The GOT pointer points to the end of the GOT section.
1688 // We need to subtract the size of the GOT section to get
1689 // the actual offset to use in the relocation.
1690 bool have_got_offset
= false;
1691 unsigned int got_offset
= 0;
1694 case elfcpp::R_386_GOT32
:
1697 gold_assert(gsym
->has_got_offset(GOT_TYPE_STANDARD
));
1698 got_offset
= (gsym
->got_offset(GOT_TYPE_STANDARD
)
1699 - target
->got_size());
1703 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
1704 gold_assert(object
->local_has_got_offset(r_sym
, GOT_TYPE_STANDARD
));
1705 got_offset
= (object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
)
1706 - target
->got_size());
1708 have_got_offset
= true;
1717 case elfcpp::R_386_NONE
:
1718 case elfcpp::R_386_GNU_VTINHERIT
:
1719 case elfcpp::R_386_GNU_VTENTRY
:
1722 case elfcpp::R_386_32
:
1723 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, true,
1725 Relocate_functions
<32, false>::rel32(view
, object
, psymval
);
1728 case elfcpp::R_386_PC32
:
1730 int ref_flags
= Symbol::NON_PIC_REF
;
1731 if (gsym
!= NULL
&& gsym
->type() == elfcpp::STT_FUNC
)
1732 ref_flags
|= Symbol::FUNCTION_CALL
;
1733 if (should_apply_static_reloc(gsym
, ref_flags
, true, output_section
))
1734 Relocate_functions
<32, false>::pcrel32(view
, object
, psymval
, address
);
1738 case elfcpp::R_386_16
:
1739 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, false,
1741 Relocate_functions
<32, false>::rel16(view
, object
, psymval
);
1744 case elfcpp::R_386_PC16
:
1746 int ref_flags
= Symbol::NON_PIC_REF
;
1747 if (gsym
!= NULL
&& gsym
->type() == elfcpp::STT_FUNC
)
1748 ref_flags
|= Symbol::FUNCTION_CALL
;
1749 if (should_apply_static_reloc(gsym
, ref_flags
, false, output_section
))
1750 Relocate_functions
<32, false>::pcrel16(view
, object
, psymval
, address
);
1754 case elfcpp::R_386_8
:
1755 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, false,
1757 Relocate_functions
<32, false>::rel8(view
, object
, psymval
);
1760 case elfcpp::R_386_PC8
:
1762 int ref_flags
= Symbol::NON_PIC_REF
;
1763 if (gsym
!= NULL
&& gsym
->type() == elfcpp::STT_FUNC
)
1764 ref_flags
|= Symbol::FUNCTION_CALL
;
1765 if (should_apply_static_reloc(gsym
, ref_flags
, false,
1767 Relocate_functions
<32, false>::pcrel8(view
, object
, psymval
, address
);
1771 case elfcpp::R_386_PLT32
:
1772 gold_assert(gsym
== NULL
1773 || gsym
->has_plt_offset()
1774 || gsym
->final_value_is_known()
1775 || (gsym
->is_defined()
1776 && !gsym
->is_from_dynobj()
1777 && !gsym
->is_preemptible()));
1778 Relocate_functions
<32, false>::pcrel32(view
, object
, psymval
, address
);
1781 case elfcpp::R_386_GOT32
:
1782 gold_assert(have_got_offset
);
1783 Relocate_functions
<32, false>::rel32(view
, got_offset
);
1786 case elfcpp::R_386_GOTOFF
:
1788 elfcpp::Elf_types
<32>::Elf_Addr value
;
1789 value
= (psymval
->value(object
, 0)
1790 - target
->got_plt_section()->address());
1791 Relocate_functions
<32, false>::rel32(view
, value
);
1795 case elfcpp::R_386_GOTPC
:
1797 elfcpp::Elf_types
<32>::Elf_Addr value
;
1798 value
= target
->got_plt_section()->address();
1799 Relocate_functions
<32, false>::pcrel32(view
, value
, address
);
1803 case elfcpp::R_386_COPY
:
1804 case elfcpp::R_386_GLOB_DAT
:
1805 case elfcpp::R_386_JUMP_SLOT
:
1806 case elfcpp::R_386_RELATIVE
:
1807 // These are outstanding tls relocs, which are unexpected when
1809 case elfcpp::R_386_TLS_TPOFF
:
1810 case elfcpp::R_386_TLS_DTPMOD32
:
1811 case elfcpp::R_386_TLS_DTPOFF32
:
1812 case elfcpp::R_386_TLS_TPOFF32
:
1813 case elfcpp::R_386_TLS_DESC
:
1814 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
1815 _("unexpected reloc %u in object file"),
1819 // These are initial tls relocs, which are expected when
1821 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1822 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
1823 case elfcpp::R_386_TLS_DESC_CALL
:
1824 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1825 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1826 case elfcpp::R_386_TLS_IE
: // Initial-exec
1827 case elfcpp::R_386_TLS_IE_32
:
1828 case elfcpp::R_386_TLS_GOTIE
:
1829 case elfcpp::R_386_TLS_LE
: // Local-exec
1830 case elfcpp::R_386_TLS_LE_32
:
1831 this->relocate_tls(relinfo
, target
, relnum
, rel
, r_type
, gsym
, psymval
,
1832 view
, address
, view_size
);
1835 case elfcpp::R_386_32PLT
:
1836 case elfcpp::R_386_TLS_GD_32
:
1837 case elfcpp::R_386_TLS_GD_PUSH
:
1838 case elfcpp::R_386_TLS_GD_CALL
:
1839 case elfcpp::R_386_TLS_GD_POP
:
1840 case elfcpp::R_386_TLS_LDM_32
:
1841 case elfcpp::R_386_TLS_LDM_PUSH
:
1842 case elfcpp::R_386_TLS_LDM_CALL
:
1843 case elfcpp::R_386_TLS_LDM_POP
:
1844 case elfcpp::R_386_USED_BY_INTEL_200
:
1846 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
1847 _("unsupported reloc %u"),
1855 // Perform a TLS relocation.
1858 Target_i386::Relocate::relocate_tls(const Relocate_info
<32, false>* relinfo
,
1859 Target_i386
* target
,
1861 const elfcpp::Rel
<32, false>& rel
,
1862 unsigned int r_type
,
1863 const Sized_symbol
<32>* gsym
,
1864 const Symbol_value
<32>* psymval
,
1865 unsigned char* view
,
1866 elfcpp::Elf_types
<32>::Elf_Addr
,
1867 section_size_type view_size
)
1869 Output_segment
* tls_segment
= relinfo
->layout
->tls_segment();
1871 const Sized_relobj
<32, false>* object
= relinfo
->object
;
1873 elfcpp::Elf_types
<32>::Elf_Addr value
= psymval
->value(object
, 0);
1875 const bool is_final
=
1877 ? !parameters
->options().output_is_position_independent()
1878 : gsym
->final_value_is_known());
1879 const tls::Tls_optimization optimized_type
1880 = Target_i386::optimize_tls_reloc(is_final
, r_type
);
1883 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1884 if (optimized_type
== tls::TLSOPT_TO_LE
)
1886 gold_assert(tls_segment
!= NULL
);
1887 this->tls_gd_to_le(relinfo
, relnum
, tls_segment
,
1888 rel
, r_type
, value
, view
,
1894 unsigned int got_type
= (optimized_type
== tls::TLSOPT_TO_IE
1895 ? GOT_TYPE_TLS_NOFFSET
1896 : GOT_TYPE_TLS_PAIR
);
1897 unsigned int got_offset
;
1900 gold_assert(gsym
->has_got_offset(got_type
));
1901 got_offset
= gsym
->got_offset(got_type
) - target
->got_size();
1905 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
1906 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
1907 got_offset
= (object
->local_got_offset(r_sym
, got_type
)
1908 - target
->got_size());
1910 if (optimized_type
== tls::TLSOPT_TO_IE
)
1912 gold_assert(tls_segment
!= NULL
);
1913 this->tls_gd_to_ie(relinfo
, relnum
, tls_segment
, rel
, r_type
,
1914 got_offset
, view
, view_size
);
1917 else if (optimized_type
== tls::TLSOPT_NONE
)
1919 // Relocate the field with the offset of the pair of GOT
1921 Relocate_functions
<32, false>::rel32(view
, got_offset
);
1925 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
1926 _("unsupported reloc %u"),
1930 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
1931 case elfcpp::R_386_TLS_DESC_CALL
:
1932 this->local_dynamic_type_
= LOCAL_DYNAMIC_GNU
;
1933 if (optimized_type
== tls::TLSOPT_TO_LE
)
1935 gold_assert(tls_segment
!= NULL
);
1936 this->tls_desc_gd_to_le(relinfo
, relnum
, tls_segment
,
1937 rel
, r_type
, value
, view
,
1943 unsigned int got_type
= (optimized_type
== tls::TLSOPT_TO_IE
1944 ? GOT_TYPE_TLS_NOFFSET
1945 : GOT_TYPE_TLS_DESC
);
1946 unsigned int got_offset
;
1949 gold_assert(gsym
->has_got_offset(got_type
));
1950 got_offset
= gsym
->got_offset(got_type
) - target
->got_size();
1954 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
1955 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
1956 got_offset
= (object
->local_got_offset(r_sym
, got_type
)
1957 - target
->got_size());
1959 if (optimized_type
== tls::TLSOPT_TO_IE
)
1961 gold_assert(tls_segment
!= NULL
);
1962 this->tls_desc_gd_to_ie(relinfo
, relnum
, tls_segment
, rel
, r_type
,
1963 got_offset
, view
, view_size
);
1966 else if (optimized_type
== tls::TLSOPT_NONE
)
1968 if (r_type
== elfcpp::R_386_TLS_GOTDESC
)
1970 // Relocate the field with the offset of the pair of GOT
1972 Relocate_functions
<32, false>::rel32(view
, got_offset
);
1977 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
1978 _("unsupported reloc %u"),
1982 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1983 if (this->local_dynamic_type_
== LOCAL_DYNAMIC_SUN
)
1985 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
1986 _("both SUN and GNU model "
1987 "TLS relocations"));
1990 this->local_dynamic_type_
= LOCAL_DYNAMIC_GNU
;
1991 if (optimized_type
== tls::TLSOPT_TO_LE
)
1993 gold_assert(tls_segment
!= NULL
);
1994 this->tls_ld_to_le(relinfo
, relnum
, tls_segment
, rel
, r_type
,
1995 value
, view
, view_size
);
1998 else if (optimized_type
== tls::TLSOPT_NONE
)
2000 // Relocate the field with the offset of the GOT entry for
2001 // the module index.
2002 unsigned int got_offset
;
2003 got_offset
= (target
->got_mod_index_entry(NULL
, NULL
, NULL
)
2004 - target
->got_size());
2005 Relocate_functions
<32, false>::rel32(view
, got_offset
);
2008 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2009 _("unsupported reloc %u"),
2013 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
2014 // This reloc can appear in debugging sections, in which case we
2015 // won't see the TLS_LDM reloc. The local_dynamic_type field
2017 if (optimized_type
== tls::TLSOPT_TO_LE
2018 && this->local_dynamic_type_
!= LOCAL_DYNAMIC_NONE
)
2020 gold_assert(tls_segment
!= NULL
);
2021 value
-= tls_segment
->memsz();
2023 Relocate_functions
<32, false>::rel32(view
, value
);
2026 case elfcpp::R_386_TLS_IE
: // Initial-exec
2027 case elfcpp::R_386_TLS_GOTIE
:
2028 case elfcpp::R_386_TLS_IE_32
:
2029 if (optimized_type
== tls::TLSOPT_TO_LE
)
2031 gold_assert(tls_segment
!= NULL
);
2032 Target_i386::Relocate::tls_ie_to_le(relinfo
, relnum
, tls_segment
,
2033 rel
, r_type
, value
, view
,
2037 else if (optimized_type
== tls::TLSOPT_NONE
)
2039 // Relocate the field with the offset of the GOT entry for
2040 // the tp-relative offset of the symbol.
2041 unsigned int got_type
= (r_type
== elfcpp::R_386_TLS_IE_32
2042 ? GOT_TYPE_TLS_OFFSET
2043 : GOT_TYPE_TLS_NOFFSET
);
2044 unsigned int got_offset
;
2047 gold_assert(gsym
->has_got_offset(got_type
));
2048 got_offset
= gsym
->got_offset(got_type
);
2052 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
2053 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
2054 got_offset
= object
->local_got_offset(r_sym
, got_type
);
2056 // For the R_386_TLS_IE relocation, we need to apply the
2057 // absolute address of the GOT entry.
2058 if (r_type
== elfcpp::R_386_TLS_IE
)
2059 got_offset
+= target
->got_plt_section()->address();
2060 // All GOT offsets are relative to the end of the GOT.
2061 got_offset
-= target
->got_size();
2062 Relocate_functions
<32, false>::rel32(view
, got_offset
);
2065 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2066 _("unsupported reloc %u"),
2070 case elfcpp::R_386_TLS_LE
: // Local-exec
2071 // If we're creating a shared library, a dynamic relocation will
2072 // have been created for this location, so do not apply it now.
2073 if (!parameters
->options().shared())
2075 gold_assert(tls_segment
!= NULL
);
2076 value
-= tls_segment
->memsz();
2077 Relocate_functions
<32, false>::rel32(view
, value
);
2081 case elfcpp::R_386_TLS_LE_32
:
2082 // If we're creating a shared library, a dynamic relocation will
2083 // have been created for this location, so do not apply it now.
2084 if (!parameters
->options().shared())
2086 gold_assert(tls_segment
!= NULL
);
2087 value
= tls_segment
->memsz() - value
;
2088 Relocate_functions
<32, false>::rel32(view
, value
);
2094 // Do a relocation in which we convert a TLS General-Dynamic to a
2098 Target_i386::Relocate::tls_gd_to_le(const Relocate_info
<32, false>* relinfo
,
2100 Output_segment
* tls_segment
,
2101 const elfcpp::Rel
<32, false>& rel
,
2103 elfcpp::Elf_types
<32>::Elf_Addr value
,
2104 unsigned char* view
,
2105 section_size_type view_size
)
2107 // leal foo(,%reg,1),%eax; call ___tls_get_addr
2108 // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
2109 // leal foo(%reg),%eax; call ___tls_get_addr
2110 // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
2112 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2113 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 9);
2115 unsigned char op1
= view
[-1];
2116 unsigned char op2
= view
[-2];
2118 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2119 op2
== 0x8d || op2
== 0x04);
2120 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[4] == 0xe8);
2126 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -3);
2127 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[-3] == 0x8d);
2128 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2129 ((op1
& 0xc7) == 0x05 && op1
!= (4 << 3)));
2130 memcpy(view
- 3, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
2134 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2135 (op1
& 0xf8) == 0x80 && (op1
& 7) != 4);
2136 if (rel
.get_r_offset() + 9 < view_size
2139 // There is a trailing nop. Use the size byte subl.
2140 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
2145 // Use the five byte subl.
2146 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
2150 value
= tls_segment
->memsz() - value
;
2151 Relocate_functions
<32, false>::rel32(view
+ roff
, value
);
2153 // The next reloc should be a PLT32 reloc against __tls_get_addr.
2155 this->skip_call_tls_get_addr_
= true;
2158 // Do a relocation in which we convert a TLS General-Dynamic to an
2162 Target_i386::Relocate::tls_gd_to_ie(const Relocate_info
<32, false>* relinfo
,
2165 const elfcpp::Rel
<32, false>& rel
,
2167 elfcpp::Elf_types
<32>::Elf_Addr value
,
2168 unsigned char* view
,
2169 section_size_type view_size
)
2171 // leal foo(,%ebx,1),%eax; call ___tls_get_addr
2172 // ==> movl %gs:0,%eax; addl foo@gotntpoff(%ebx),%eax
2174 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2175 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 9);
2177 unsigned char op1
= view
[-1];
2178 unsigned char op2
= view
[-2];
2180 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2181 op2
== 0x8d || op2
== 0x04);
2182 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[4] == 0xe8);
2186 // FIXME: For now, support only the first (SIB) form.
2187 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), op2
== 0x04);
2191 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -3);
2192 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[-3] == 0x8d);
2193 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2194 ((op1
& 0xc7) == 0x05 && op1
!= (4 << 3)));
2195 memcpy(view
- 3, "\x65\xa1\0\0\0\0\x03\x83\0\0\0", 12);
2199 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2200 (op1
& 0xf8) == 0x80 && (op1
& 7) != 4);
2201 if (rel
.get_r_offset() + 9 < view_size
2204 // FIXME: This is not the right instruction sequence.
2205 // There is a trailing nop. Use the size byte subl.
2206 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
2211 // FIXME: This is not the right instruction sequence.
2212 // Use the five byte subl.
2213 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
2217 Relocate_functions
<32, false>::rel32(view
+ roff
, value
);
2219 // The next reloc should be a PLT32 reloc against __tls_get_addr.
2221 this->skip_call_tls_get_addr_
= true;
2224 // Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL
2225 // General-Dynamic to a Local-Exec.
2228 Target_i386::Relocate::tls_desc_gd_to_le(
2229 const Relocate_info
<32, false>* relinfo
,
2231 Output_segment
* tls_segment
,
2232 const elfcpp::Rel
<32, false>& rel
,
2233 unsigned int r_type
,
2234 elfcpp::Elf_types
<32>::Elf_Addr value
,
2235 unsigned char* view
,
2236 section_size_type view_size
)
2238 if (r_type
== elfcpp::R_386_TLS_GOTDESC
)
2240 // leal foo@TLSDESC(%ebx), %eax
2241 // ==> leal foo@NTPOFF, %eax
2242 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2243 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
2244 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2245 view
[-2] == 0x8d && view
[-1] == 0x83);
2247 value
-= tls_segment
->memsz();
2248 Relocate_functions
<32, false>::rel32(view
, value
);
2252 // call *foo@TLSCALL(%eax)
2254 gold_assert(r_type
== elfcpp::R_386_TLS_DESC_CALL
);
2255 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 2);
2256 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2257 view
[0] == 0xff && view
[1] == 0x10);
2263 // Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL
2264 // General-Dynamic to an Initial-Exec.
2267 Target_i386::Relocate::tls_desc_gd_to_ie(
2268 const Relocate_info
<32, false>* relinfo
,
2271 const elfcpp::Rel
<32, false>& rel
,
2272 unsigned int r_type
,
2273 elfcpp::Elf_types
<32>::Elf_Addr value
,
2274 unsigned char* view
,
2275 section_size_type view_size
)
2277 if (r_type
== elfcpp::R_386_TLS_GOTDESC
)
2279 // leal foo@TLSDESC(%ebx), %eax
2280 // ==> movl foo@GOTNTPOFF(%ebx), %eax
2281 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2282 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
2283 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2284 view
[-2] == 0x8d && view
[-1] == 0x83);
2286 Relocate_functions
<32, false>::rel32(view
, value
);
2290 // call *foo@TLSCALL(%eax)
2292 gold_assert(r_type
== elfcpp::R_386_TLS_DESC_CALL
);
2293 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 2);
2294 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2295 view
[0] == 0xff && view
[1] == 0x10);
2301 // Do a relocation in which we convert a TLS Local-Dynamic to a
2305 Target_i386::Relocate::tls_ld_to_le(const Relocate_info
<32, false>* relinfo
,
2308 const elfcpp::Rel
<32, false>& rel
,
2310 elfcpp::Elf_types
<32>::Elf_Addr
,
2311 unsigned char* view
,
2312 section_size_type view_size
)
2314 // leal foo(%reg), %eax; call ___tls_get_addr
2315 // ==> movl %gs:0,%eax; nop; leal 0(%esi,1),%esi
2317 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2318 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 9);
2320 // FIXME: Does this test really always pass?
2321 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2322 view
[-2] == 0x8d && view
[-1] == 0x83);
2324 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[4] == 0xe8);
2326 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x90\x8d\x74\x26\0", 11);
2328 // The next reloc should be a PLT32 reloc against __tls_get_addr.
2330 this->skip_call_tls_get_addr_
= true;
2333 // Do a relocation in which we convert a TLS Initial-Exec to a
2337 Target_i386::Relocate::tls_ie_to_le(const Relocate_info
<32, false>* relinfo
,
2339 Output_segment
* tls_segment
,
2340 const elfcpp::Rel
<32, false>& rel
,
2341 unsigned int r_type
,
2342 elfcpp::Elf_types
<32>::Elf_Addr value
,
2343 unsigned char* view
,
2344 section_size_type view_size
)
2346 // We have to actually change the instructions, which means that we
2347 // need to examine the opcodes to figure out which instruction we
2349 if (r_type
== elfcpp::R_386_TLS_IE
)
2351 // movl %gs:XX,%eax ==> movl $YY,%eax
2352 // movl %gs:XX,%reg ==> movl $YY,%reg
2353 // addl %gs:XX,%reg ==> addl $YY,%reg
2354 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -1);
2355 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
2357 unsigned char op1
= view
[-1];
2360 // movl XX,%eax ==> movl $YY,%eax
2365 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2367 unsigned char op2
= view
[-2];
2370 // movl XX,%reg ==> movl $YY,%reg
2371 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2372 (op1
& 0xc7) == 0x05);
2374 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
2376 else if (op2
== 0x03)
2378 // addl XX,%reg ==> addl $YY,%reg
2379 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2380 (op1
& 0xc7) == 0x05);
2382 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
2385 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), 0);
2390 // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2
2391 // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2
2392 // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2
2393 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2394 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
2396 unsigned char op1
= view
[-1];
2397 unsigned char op2
= view
[-2];
2398 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2399 (op1
& 0xc0) == 0x80 && (op1
& 7) != 4);
2402 // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2
2404 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
2406 else if (op2
== 0x2b)
2408 // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2
2410 view
[-1] = 0xe8 | ((op1
>> 3) & 7);
2412 else if (op2
== 0x03)
2414 // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2
2416 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
2419 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), 0);
2422 value
= tls_segment
->memsz() - value
;
2423 if (r_type
== elfcpp::R_386_TLS_IE
|| r_type
== elfcpp::R_386_TLS_GOTIE
)
2426 Relocate_functions
<32, false>::rel32(view
, value
);
2429 // Relocate section data.
2432 Target_i386::relocate_section(const Relocate_info
<32, false>* relinfo
,
2433 unsigned int sh_type
,
2434 const unsigned char* prelocs
,
2436 Output_section
* output_section
,
2437 bool needs_special_offset_handling
,
2438 unsigned char* view
,
2439 elfcpp::Elf_types
<32>::Elf_Addr address
,
2440 section_size_type view_size
)
2442 gold_assert(sh_type
== elfcpp::SHT_REL
);
2444 gold::relocate_section
<32, false, Target_i386
, elfcpp::SHT_REL
,
2445 Target_i386::Relocate
>(
2451 needs_special_offset_handling
,
2457 // Return the size of a relocation while scanning during a relocatable
2461 Target_i386::Relocatable_size_for_reloc::get_size_for_reloc(
2462 unsigned int r_type
,
2467 case elfcpp::R_386_NONE
:
2468 case elfcpp::R_386_GNU_VTINHERIT
:
2469 case elfcpp::R_386_GNU_VTENTRY
:
2470 case elfcpp::R_386_TLS_GD
: // Global-dynamic
2471 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
2472 case elfcpp::R_386_TLS_DESC_CALL
:
2473 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
2474 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
2475 case elfcpp::R_386_TLS_IE
: // Initial-exec
2476 case elfcpp::R_386_TLS_IE_32
:
2477 case elfcpp::R_386_TLS_GOTIE
:
2478 case elfcpp::R_386_TLS_LE
: // Local-exec
2479 case elfcpp::R_386_TLS_LE_32
:
2482 case elfcpp::R_386_32
:
2483 case elfcpp::R_386_PC32
:
2484 case elfcpp::R_386_GOT32
:
2485 case elfcpp::R_386_PLT32
:
2486 case elfcpp::R_386_GOTOFF
:
2487 case elfcpp::R_386_GOTPC
:
2490 case elfcpp::R_386_16
:
2491 case elfcpp::R_386_PC16
:
2494 case elfcpp::R_386_8
:
2495 case elfcpp::R_386_PC8
:
2498 // These are relocations which should only be seen by the
2499 // dynamic linker, and should never be seen here.
2500 case elfcpp::R_386_COPY
:
2501 case elfcpp::R_386_GLOB_DAT
:
2502 case elfcpp::R_386_JUMP_SLOT
:
2503 case elfcpp::R_386_RELATIVE
:
2504 case elfcpp::R_386_TLS_TPOFF
:
2505 case elfcpp::R_386_TLS_DTPMOD32
:
2506 case elfcpp::R_386_TLS_DTPOFF32
:
2507 case elfcpp::R_386_TLS_TPOFF32
:
2508 case elfcpp::R_386_TLS_DESC
:
2509 object
->error(_("unexpected reloc %u in object file"), r_type
);
2512 case elfcpp::R_386_32PLT
:
2513 case elfcpp::R_386_TLS_GD_32
:
2514 case elfcpp::R_386_TLS_GD_PUSH
:
2515 case elfcpp::R_386_TLS_GD_CALL
:
2516 case elfcpp::R_386_TLS_GD_POP
:
2517 case elfcpp::R_386_TLS_LDM_32
:
2518 case elfcpp::R_386_TLS_LDM_PUSH
:
2519 case elfcpp::R_386_TLS_LDM_CALL
:
2520 case elfcpp::R_386_TLS_LDM_POP
:
2521 case elfcpp::R_386_USED_BY_INTEL_200
:
2523 object
->error(_("unsupported reloc %u in object file"), r_type
);
2528 // Scan the relocs during a relocatable link.
2531 Target_i386::scan_relocatable_relocs(const General_options
& options
,
2532 Symbol_table
* symtab
,
2534 Sized_relobj
<32, false>* object
,
2535 unsigned int data_shndx
,
2536 unsigned int sh_type
,
2537 const unsigned char* prelocs
,
2539 Output_section
* output_section
,
2540 bool needs_special_offset_handling
,
2541 size_t local_symbol_count
,
2542 const unsigned char* plocal_symbols
,
2543 Relocatable_relocs
* rr
)
2545 gold_assert(sh_type
== elfcpp::SHT_REL
);
2547 typedef gold::Default_scan_relocatable_relocs
<elfcpp::SHT_REL
,
2548 Relocatable_size_for_reloc
> Scan_relocatable_relocs
;
2550 gold::scan_relocatable_relocs
<32, false, elfcpp::SHT_REL
,
2551 Scan_relocatable_relocs
>(
2560 needs_special_offset_handling
,
2566 // Relocate a section during a relocatable link.
2569 Target_i386::relocate_for_relocatable(
2570 const Relocate_info
<32, false>* relinfo
,
2571 unsigned int sh_type
,
2572 const unsigned char* prelocs
,
2574 Output_section
* output_section
,
2575 off_t offset_in_output_section
,
2576 const Relocatable_relocs
* rr
,
2577 unsigned char* view
,
2578 elfcpp::Elf_types
<32>::Elf_Addr view_address
,
2579 section_size_type view_size
,
2580 unsigned char* reloc_view
,
2581 section_size_type reloc_view_size
)
2583 gold_assert(sh_type
== elfcpp::SHT_REL
);
2585 gold::relocate_for_relocatable
<32, false, elfcpp::SHT_REL
>(
2590 offset_in_output_section
,
2599 // Return the value to use for a dynamic which requires special
2600 // treatment. This is how we support equality comparisons of function
2601 // pointers across shared library boundaries, as described in the
2602 // processor specific ABI supplement.
2605 Target_i386::do_dynsym_value(const Symbol
* gsym
) const
2607 gold_assert(gsym
->is_from_dynobj() && gsym
->has_plt_offset());
2608 return this->plt_section()->address() + gsym
->plt_offset();
2611 // Return a string used to fill a code section with nops to take up
2612 // the specified length.
2615 Target_i386::do_code_fill(section_size_type length
) const
2619 // Build a jmp instruction to skip over the bytes.
2620 unsigned char jmp
[5];
2622 elfcpp::Swap_unaligned
<32, false>::writeval(jmp
+ 1, length
- 5);
2623 return (std::string(reinterpret_cast<char*>(&jmp
[0]), 5)
2624 + std::string(length
- 5, '\0'));
2627 // Nop sequences of various lengths.
2628 const char nop1
[1] = { 0x90 }; // nop
2629 const char nop2
[2] = { 0x66, 0x90 }; // xchg %ax %ax
2630 const char nop3
[3] = { 0x8d, 0x76, 0x00 }; // leal 0(%esi),%esi
2631 const char nop4
[4] = { 0x8d, 0x74, 0x26, 0x00}; // leal 0(%esi,1),%esi
2632 const char nop5
[5] = { 0x90, 0x8d, 0x74, 0x26, // nop
2633 0x00 }; // leal 0(%esi,1),%esi
2634 const char nop6
[6] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2636 const char nop7
[7] = { 0x8d, 0xb4, 0x26, 0x00, // leal 0L(%esi,1),%esi
2638 const char nop8
[8] = { 0x90, 0x8d, 0xb4, 0x26, // nop
2639 0x00, 0x00, 0x00, 0x00 }; // leal 0L(%esi,1),%esi
2640 const char nop9
[9] = { 0x89, 0xf6, 0x8d, 0xbc, // movl %esi,%esi
2641 0x27, 0x00, 0x00, 0x00, // leal 0L(%edi,1),%edi
2643 const char nop10
[10] = { 0x8d, 0x76, 0x00, 0x8d, // leal 0(%esi),%esi
2644 0xbc, 0x27, 0x00, 0x00, // leal 0L(%edi,1),%edi
2646 const char nop11
[11] = { 0x8d, 0x74, 0x26, 0x00, // leal 0(%esi,1),%esi
2647 0x8d, 0xbc, 0x27, 0x00, // leal 0L(%edi,1),%edi
2649 const char nop12
[12] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2650 0x00, 0x00, 0x8d, 0xbf, // leal 0L(%edi),%edi
2651 0x00, 0x00, 0x00, 0x00 };
2652 const char nop13
[13] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2653 0x00, 0x00, 0x8d, 0xbc, // leal 0L(%edi,1),%edi
2654 0x27, 0x00, 0x00, 0x00,
2656 const char nop14
[14] = { 0x8d, 0xb4, 0x26, 0x00, // leal 0L(%esi,1),%esi
2657 0x00, 0x00, 0x00, 0x8d, // leal 0L(%edi,1),%edi
2658 0xbc, 0x27, 0x00, 0x00,
2660 const char nop15
[15] = { 0xeb, 0x0d, 0x90, 0x90, // jmp .+15
2661 0x90, 0x90, 0x90, 0x90, // nop,nop,nop,...
2662 0x90, 0x90, 0x90, 0x90,
2665 const char* nops
[16] = {
2667 nop1
, nop2
, nop3
, nop4
, nop5
, nop6
, nop7
,
2668 nop8
, nop9
, nop10
, nop11
, nop12
, nop13
, nop14
, nop15
2671 return std::string(nops
[length
], length
);
2674 // The selector for i386 object files.
2676 class Target_selector_i386
: public Target_selector_freebsd
2679 Target_selector_i386()
2680 : Target_selector_freebsd(elfcpp::EM_386
, 32, false,
2681 "elf32-i386", "elf32-i386-freebsd")
2685 do_instantiate_target()
2686 { return new Target_i386(); }
2689 Target_selector_i386 target_selector_i386
;
2691 } // End anonymous namespace.