1 // i386.cc -- i386 target support for gold.
3 // Copyright 2006, 2007 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"
36 #include "target-reloc.h"
37 #include "target-select.h"
45 class Output_data_plt_i386
;
47 // The i386 target class.
48 // TLS info comes from
49 // http://people.redhat.com/drepper/tls.pdf
50 // http://www.lsd.ic.unicamp.br/~oliva/writeups/TLS/RFC-TLSDESC-x86.txt
52 class Target_i386
: public Sized_target
<32, false>
55 typedef Output_data_reloc
<elfcpp::SHT_REL
, true, 32, false> Reloc_section
;
58 : Sized_target
<32, false>(&i386_info
),
59 got_(NULL
), plt_(NULL
), got_plt_(NULL
), rel_dyn_(NULL
),
60 copy_relocs_(NULL
), dynbss_(NULL
), got_mod_index_offset_(-1U)
63 // Scan the relocations to look for symbol adjustments.
65 scan_relocs(const General_options
& options
,
68 Sized_relobj
<32, false>* object
,
69 unsigned int data_shndx
,
71 const unsigned char* prelocs
,
73 Output_section
* output_section
,
74 bool needs_special_offset_handling
,
75 size_t local_symbol_count
,
76 const unsigned char* plocal_symbols
);
78 // Finalize the sections.
80 do_finalize_sections(Layout
*);
82 // Return the value to use for a dynamic which requires special
85 do_dynsym_value(const Symbol
*) const;
87 // Relocate a section.
89 relocate_section(const Relocate_info
<32, false>*,
91 const unsigned char* prelocs
,
93 Output_section
* output_section
,
94 bool needs_special_offset_handling
,
96 elfcpp::Elf_types
<32>::Elf_Addr view_address
,
97 section_size_type view_size
);
99 // Return a string used to fill a code section with nops.
101 do_code_fill(section_size_type length
);
103 // Return whether SYM is defined by the ABI.
105 do_is_defined_by_abi(Symbol
* sym
) const
106 { return strcmp(sym
->name(), "___tls_get_addr") == 0; }
108 // Return the size of the GOT section.
112 gold_assert(this->got_
!= NULL
);
113 return this->got_
->data_size();
117 // The class which scans relocations.
121 local(const General_options
& options
, Symbol_table
* symtab
,
122 Layout
* layout
, Target_i386
* target
,
123 Sized_relobj
<32, false>* object
,
124 unsigned int data_shndx
,
125 Output_section
* output_section
,
126 const elfcpp::Rel
<32, false>& reloc
, unsigned int r_type
,
127 const elfcpp::Sym
<32, false>& lsym
);
130 global(const General_options
& options
, Symbol_table
* symtab
,
131 Layout
* layout
, Target_i386
* target
,
132 Sized_relobj
<32, false>* object
,
133 unsigned int data_shndx
,
134 Output_section
* output_section
,
135 const elfcpp::Rel
<32, false>& reloc
, unsigned int r_type
,
139 unsupported_reloc_local(Sized_relobj
<32, false>*, unsigned int r_type
);
142 unsupported_reloc_global(Sized_relobj
<32, false>*, unsigned int r_type
,
146 // The class which implements relocation.
151 : skip_call_tls_get_addr_(false),
152 local_dynamic_type_(LOCAL_DYNAMIC_NONE
)
157 if (this->skip_call_tls_get_addr_
)
159 // FIXME: This needs to specify the location somehow.
160 gold_error(_("missing expected TLS relocation"));
164 // Return whether the static relocation needs to be applied.
166 should_apply_static_reloc(const Sized_symbol
<32>* gsym
,
170 // Do a relocation. Return false if the caller should not issue
171 // any warnings about this relocation.
173 relocate(const Relocate_info
<32, false>*, Target_i386
*, size_t relnum
,
174 const elfcpp::Rel
<32, false>&,
175 unsigned int r_type
, const Sized_symbol
<32>*,
176 const Symbol_value
<32>*,
177 unsigned char*, elfcpp::Elf_types
<32>::Elf_Addr
,
181 // Do a TLS relocation.
183 relocate_tls(const Relocate_info
<32, false>*, Target_i386
* target
,
184 size_t relnum
, const elfcpp::Rel
<32, false>&,
185 unsigned int r_type
, const Sized_symbol
<32>*,
186 const Symbol_value
<32>*,
187 unsigned char*, elfcpp::Elf_types
<32>::Elf_Addr
,
190 // Do a TLS General-Dynamic to Initial-Exec transition.
192 tls_gd_to_ie(const Relocate_info
<32, false>*, size_t relnum
,
193 Output_segment
* tls_segment
,
194 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
195 elfcpp::Elf_types
<32>::Elf_Addr value
,
197 section_size_type view_size
);
199 // Do a TLS General-Dynamic to Local-Exec transition.
201 tls_gd_to_le(const Relocate_info
<32, false>*, size_t relnum
,
202 Output_segment
* tls_segment
,
203 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
204 elfcpp::Elf_types
<32>::Elf_Addr value
,
206 section_size_type view_size
);
208 // Do a TLS Local-Dynamic to Local-Exec transition.
210 tls_ld_to_le(const Relocate_info
<32, false>*, size_t relnum
,
211 Output_segment
* tls_segment
,
212 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
213 elfcpp::Elf_types
<32>::Elf_Addr value
,
215 section_size_type view_size
);
217 // Do a TLS Initial-Exec to Local-Exec transition.
219 tls_ie_to_le(const Relocate_info
<32, false>*, size_t relnum
,
220 Output_segment
* tls_segment
,
221 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
222 elfcpp::Elf_types
<32>::Elf_Addr value
,
224 section_size_type view_size
);
226 // We need to keep track of which type of local dynamic relocation
227 // we have seen, so that we can optimize R_386_TLS_LDO_32 correctly.
228 enum Local_dynamic_type
235 // This is set if we should skip the next reloc, which should be a
236 // PLT32 reloc against ___tls_get_addr.
237 bool skip_call_tls_get_addr_
;
238 // The type of local dynamic relocation we have seen in the section
239 // being relocated, if any.
240 Local_dynamic_type local_dynamic_type_
;
243 // Adjust TLS relocation type based on the options and whether this
244 // is a local symbol.
245 static tls::Tls_optimization
246 optimize_tls_reloc(bool is_final
, int r_type
);
248 // Get the GOT section, creating it if necessary.
249 Output_data_got
<32, false>*
250 got_section(Symbol_table
*, Layout
*);
252 // Get the GOT PLT section.
254 got_plt_section() const
256 gold_assert(this->got_plt_
!= NULL
);
257 return this->got_plt_
;
260 // Create a PLT entry for a global symbol.
262 make_plt_entry(Symbol_table
*, Layout
*, Symbol
*);
264 // Create a GOT entry for the TLS module index.
266 got_mod_index_entry(Symbol_table
* symtab
, Layout
* layout
,
267 Sized_relobj
<32, false>* object
);
269 // Get the PLT section.
270 const Output_data_plt_i386
*
273 gold_assert(this->plt_
!= NULL
);
277 // Get the dynamic reloc section, creating it if necessary.
279 rel_dyn_section(Layout
*);
281 // Return true if the symbol may need a COPY relocation.
282 // References from an executable object to non-function symbols
283 // defined in a dynamic object may need a COPY relocation.
285 may_need_copy_reloc(Symbol
* gsym
)
287 return (!parameters
->output_is_shared()
288 && gsym
->is_from_dynobj()
289 && gsym
->type() != elfcpp::STT_FUNC
);
292 // Copy a relocation against a global symbol.
294 copy_reloc(const General_options
*, Symbol_table
*, Layout
*,
295 Sized_relobj
<32, false>*, unsigned int,
296 Output_section
*, Symbol
*, const elfcpp::Rel
<32, false>&);
298 // Information about this specific target which we pass to the
299 // general Target structure.
300 static const Target::Target_info i386_info
;
303 Output_data_got
<32, false>* got_
;
305 Output_data_plt_i386
* plt_
;
306 // The GOT PLT section.
307 Output_data_space
* got_plt_
;
308 // The dynamic reloc section.
309 Reloc_section
* rel_dyn_
;
310 // Relocs saved to avoid a COPY reloc.
311 Copy_relocs
<32, false>* copy_relocs_
;
312 // Space for variables copied with a COPY reloc.
313 Output_data_space
* dynbss_
;
314 // Offset of the GOT entry for the TLS module index;
315 unsigned int got_mod_index_offset_
;
318 const Target::Target_info
Target_i386::i386_info
=
321 false, // is_big_endian
322 elfcpp::EM_386
, // machine_code
323 false, // has_make_symbol
324 false, // has_resolve
325 true, // has_code_fill
326 true, // is_default_stack_executable
327 "/usr/lib/libc.so.1", // dynamic_linker
328 0x08048000, // default_text_segment_address
329 0x1000, // abi_pagesize
330 0x1000 // common_pagesize
333 // Get the GOT section, creating it if necessary.
335 Output_data_got
<32, false>*
336 Target_i386::got_section(Symbol_table
* symtab
, Layout
* layout
)
338 if (this->got_
== NULL
)
340 gold_assert(symtab
!= NULL
&& layout
!= NULL
);
342 this->got_
= new Output_data_got
<32, false>();
344 layout
->add_output_section_data(".got", elfcpp::SHT_PROGBITS
,
345 elfcpp::SHF_ALLOC
| elfcpp::SHF_WRITE
,
348 // The old GNU linker creates a .got.plt section. We just
349 // create another set of data in the .got section. Note that we
350 // always create a PLT if we create a GOT, although the PLT
352 this->got_plt_
= new Output_data_space(4);
353 layout
->add_output_section_data(".got", elfcpp::SHT_PROGBITS
,
354 elfcpp::SHF_ALLOC
| elfcpp::SHF_WRITE
,
357 // The first three entries are reserved.
358 this->got_plt_
->set_current_data_size(3 * 4);
360 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
361 symtab
->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL
,
363 0, 0, elfcpp::STT_OBJECT
,
365 elfcpp::STV_HIDDEN
, 0,
372 // Get the dynamic reloc section, creating it if necessary.
374 Target_i386::Reloc_section
*
375 Target_i386::rel_dyn_section(Layout
* layout
)
377 if (this->rel_dyn_
== NULL
)
379 gold_assert(layout
!= NULL
);
380 this->rel_dyn_
= new Reloc_section();
381 layout
->add_output_section_data(".rel.dyn", elfcpp::SHT_REL
,
382 elfcpp::SHF_ALLOC
, this->rel_dyn_
);
384 return this->rel_dyn_
;
387 // A class to handle the PLT data.
389 class Output_data_plt_i386
: public Output_section_data
392 typedef Output_data_reloc
<elfcpp::SHT_REL
, true, 32, false> Reloc_section
;
394 Output_data_plt_i386(Layout
*, Output_data_space
*);
396 // Add an entry to the PLT.
398 add_entry(Symbol
* gsym
);
400 // Return the .rel.plt section data.
403 { return this->rel_
; }
407 do_adjust_output_section(Output_section
* os
);
410 // The size of an entry in the PLT.
411 static const int plt_entry_size
= 16;
413 // The first entry in the PLT for an executable.
414 static unsigned char exec_first_plt_entry
[plt_entry_size
];
416 // The first entry in the PLT for a shared object.
417 static unsigned char dyn_first_plt_entry
[plt_entry_size
];
419 // Other entries in the PLT for an executable.
420 static unsigned char exec_plt_entry
[plt_entry_size
];
422 // Other entries in the PLT for a shared object.
423 static unsigned char dyn_plt_entry
[plt_entry_size
];
425 // Set the final size.
427 set_final_data_size()
428 { this->set_data_size((this->count_
+ 1) * plt_entry_size
); }
430 // Write out the PLT data.
432 do_write(Output_file
*);
434 // The reloc section.
436 // The .got.plt section.
437 Output_data_space
* got_plt_
;
438 // The number of PLT entries.
442 // Create the PLT section. The ordinary .got section is an argument,
443 // since we need to refer to the start. We also create our own .got
444 // section just for PLT entries.
446 Output_data_plt_i386::Output_data_plt_i386(Layout
* layout
,
447 Output_data_space
* got_plt
)
448 : Output_section_data(4), got_plt_(got_plt
), count_(0)
450 this->rel_
= new Reloc_section();
451 layout
->add_output_section_data(".rel.plt", elfcpp::SHT_REL
,
452 elfcpp::SHF_ALLOC
, this->rel_
);
456 Output_data_plt_i386::do_adjust_output_section(Output_section
* os
)
458 // UnixWare sets the entsize of .plt to 4, and so does the old GNU
459 // linker, and so do we.
463 // Add an entry to the PLT.
466 Output_data_plt_i386::add_entry(Symbol
* gsym
)
468 gold_assert(!gsym
->has_plt_offset());
470 // Note that when setting the PLT offset we skip the initial
471 // reserved PLT entry.
472 gsym
->set_plt_offset((this->count_
+ 1) * plt_entry_size
);
476 section_offset_type got_offset
= this->got_plt_
->current_data_size();
478 // Every PLT entry needs a GOT entry which points back to the PLT
479 // entry (this will be changed by the dynamic linker, normally
480 // lazily when the function is called).
481 this->got_plt_
->set_current_data_size(got_offset
+ 4);
483 // Every PLT entry needs a reloc.
484 gsym
->set_needs_dynsym_entry();
485 this->rel_
->add_global(gsym
, elfcpp::R_386_JUMP_SLOT
, this->got_plt_
,
488 // Note that we don't need to save the symbol. The contents of the
489 // PLT are independent of which symbols are used. The symbols only
490 // appear in the relocations.
493 // The first entry in the PLT for an executable.
495 unsigned char Output_data_plt_i386::exec_first_plt_entry
[plt_entry_size
] =
497 0xff, 0x35, // pushl contents of memory address
498 0, 0, 0, 0, // replaced with address of .got + 4
499 0xff, 0x25, // jmp indirect
500 0, 0, 0, 0, // replaced with address of .got + 8
504 // The first entry in the PLT for a shared object.
506 unsigned char Output_data_plt_i386::dyn_first_plt_entry
[plt_entry_size
] =
508 0xff, 0xb3, 4, 0, 0, 0, // pushl 4(%ebx)
509 0xff, 0xa3, 8, 0, 0, 0, // jmp *8(%ebx)
513 // Subsequent entries in the PLT for an executable.
515 unsigned char Output_data_plt_i386::exec_plt_entry
[plt_entry_size
] =
517 0xff, 0x25, // jmp indirect
518 0, 0, 0, 0, // replaced with address of symbol in .got
519 0x68, // pushl immediate
520 0, 0, 0, 0, // replaced with offset into relocation table
521 0xe9, // jmp relative
522 0, 0, 0, 0 // replaced with offset to start of .plt
525 // Subsequent entries in the PLT for a shared object.
527 unsigned char Output_data_plt_i386::dyn_plt_entry
[plt_entry_size
] =
529 0xff, 0xa3, // jmp *offset(%ebx)
530 0, 0, 0, 0, // replaced with offset of symbol in .got
531 0x68, // pushl immediate
532 0, 0, 0, 0, // replaced with offset into relocation table
533 0xe9, // jmp relative
534 0, 0, 0, 0 // replaced with offset to start of .plt
537 // Write out the PLT. This uses the hand-coded instructions above,
538 // and adjusts them as needed. This is all specified by the i386 ELF
539 // Processor Supplement.
542 Output_data_plt_i386::do_write(Output_file
* of
)
544 const off_t offset
= this->offset();
545 const section_size_type oview_size
=
546 convert_to_section_size_type(this->data_size());
547 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
549 const off_t got_file_offset
= this->got_plt_
->offset();
550 const section_size_type got_size
=
551 convert_to_section_size_type(this->got_plt_
->data_size());
552 unsigned char* const got_view
= of
->get_output_view(got_file_offset
,
555 unsigned char* pov
= oview
;
557 elfcpp::Elf_types
<32>::Elf_Addr plt_address
= this->address();
558 elfcpp::Elf_types
<32>::Elf_Addr got_address
= this->got_plt_
->address();
560 if (parameters
->output_is_shared())
561 memcpy(pov
, dyn_first_plt_entry
, plt_entry_size
);
564 memcpy(pov
, exec_first_plt_entry
, plt_entry_size
);
565 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2, got_address
+ 4);
566 elfcpp::Swap
<32, false>::writeval(pov
+ 8, got_address
+ 8);
568 pov
+= plt_entry_size
;
570 unsigned char* got_pov
= got_view
;
572 memset(got_pov
, 0, 12);
575 const int rel_size
= elfcpp::Elf_sizes
<32>::rel_size
;
577 unsigned int plt_offset
= plt_entry_size
;
578 unsigned int plt_rel_offset
= 0;
579 unsigned int got_offset
= 12;
580 const unsigned int count
= this->count_
;
581 for (unsigned int i
= 0;
584 pov
+= plt_entry_size
,
586 plt_offset
+= plt_entry_size
,
587 plt_rel_offset
+= rel_size
,
590 // Set and adjust the PLT entry itself.
592 if (parameters
->output_is_shared())
594 memcpy(pov
, dyn_plt_entry
, plt_entry_size
);
595 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2, got_offset
);
599 memcpy(pov
, exec_plt_entry
, plt_entry_size
);
600 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
605 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 7, plt_rel_offset
);
606 elfcpp::Swap
<32, false>::writeval(pov
+ 12,
607 - (plt_offset
+ plt_entry_size
));
609 // Set the entry in the GOT.
610 elfcpp::Swap
<32, false>::writeval(got_pov
, plt_address
+ plt_offset
+ 6);
613 gold_assert(static_cast<section_size_type
>(pov
- oview
) == oview_size
);
614 gold_assert(static_cast<section_size_type
>(got_pov
- got_view
) == got_size
);
616 of
->write_output_view(offset
, oview_size
, oview
);
617 of
->write_output_view(got_file_offset
, got_size
, got_view
);
620 // Create a PLT entry for a global symbol.
623 Target_i386::make_plt_entry(Symbol_table
* symtab
, Layout
* layout
, Symbol
* gsym
)
625 if (gsym
->has_plt_offset())
628 if (this->plt_
== NULL
)
630 // Create the GOT sections first.
631 this->got_section(symtab
, layout
);
633 this->plt_
= new Output_data_plt_i386(layout
, this->got_plt_
);
634 layout
->add_output_section_data(".plt", elfcpp::SHT_PROGBITS
,
636 | elfcpp::SHF_EXECINSTR
),
640 this->plt_
->add_entry(gsym
);
643 // Create a GOT entry for the TLS module index.
646 Target_i386::got_mod_index_entry(Symbol_table
* symtab
, Layout
* layout
,
647 Sized_relobj
<32, false>* object
)
649 if (this->got_mod_index_offset_
== -1U)
651 gold_assert(symtab
!= NULL
&& layout
!= NULL
&& object
!= NULL
);
652 Reloc_section
* rel_dyn
= this->rel_dyn_section(layout
);
653 Output_data_got
<32, false>* got
= this->got_section(symtab
, layout
);
654 unsigned int got_offset
= got
->add_constant(0);
655 rel_dyn
->add_local(object
, 0, elfcpp::R_386_TLS_DTPMOD32
, got
,
657 got
->add_constant(0);
658 this->got_mod_index_offset_
= got_offset
;
660 return this->got_mod_index_offset_
;
663 // Handle a relocation against a non-function symbol defined in a
664 // dynamic object. The traditional way to handle this is to generate
665 // a COPY relocation to copy the variable at runtime from the shared
666 // object into the executable's data segment. However, this is
667 // undesirable in general, as if the size of the object changes in the
668 // dynamic object, the executable will no longer work correctly. If
669 // this relocation is in a writable section, then we can create a
670 // dynamic reloc and the dynamic linker will resolve it to the correct
671 // address at runtime. However, we do not want do that if the
672 // relocation is in a read-only section, as it would prevent the
673 // readonly segment from being shared. And if we have to eventually
674 // generate a COPY reloc, then any dynamic relocations will be
675 // useless. So this means that if this is a writable section, we need
676 // to save the relocation until we see whether we have to create a
677 // COPY relocation for this symbol for any other relocation.
680 Target_i386::copy_reloc(const General_options
* options
,
681 Symbol_table
* symtab
,
683 Sized_relobj
<32, false>* object
,
684 unsigned int data_shndx
,
685 Output_section
* output_section
,
687 const elfcpp::Rel
<32, false>& rel
)
689 Sized_symbol
<32>* ssym
;
690 ssym
= symtab
->get_sized_symbol
SELECT_SIZE_NAME(32) (gsym
693 if (!Copy_relocs
<32, false>::need_copy_reloc(options
, object
,
696 // So far we do not need a COPY reloc. Save this relocation.
697 // If it turns out that we never need a COPY reloc for this
698 // symbol, then we will emit the relocation.
699 if (this->copy_relocs_
== NULL
)
700 this->copy_relocs_
= new Copy_relocs
<32, false>();
701 this->copy_relocs_
->save(ssym
, object
, data_shndx
, output_section
, rel
);
705 // Allocate space for this symbol in the .bss section.
707 elfcpp::Elf_types
<32>::Elf_WXword symsize
= ssym
->symsize();
709 // There is no defined way to determine the required alignment
710 // of the symbol. We pick the alignment based on the size. We
711 // set an arbitrary maximum of 256.
713 for (align
= 1; align
< 512; align
<<= 1)
714 if ((symsize
& align
) != 0)
717 if (this->dynbss_
== NULL
)
719 this->dynbss_
= new Output_data_space(align
);
720 layout
->add_output_section_data(".bss",
723 | elfcpp::SHF_WRITE
),
727 Output_data_space
* dynbss
= this->dynbss_
;
729 if (align
> dynbss
->addralign())
730 dynbss
->set_space_alignment(align
);
732 section_size_type dynbss_size
=
733 convert_to_section_size_type(dynbss
->current_data_size());
734 dynbss_size
= align_address(dynbss_size
, align
);
735 section_size_type offset
= dynbss_size
;
736 dynbss
->set_current_data_size(dynbss_size
+ symsize
);
738 symtab
->define_with_copy_reloc(ssym
, dynbss
, offset
);
740 // Add the COPY reloc.
741 Reloc_section
* rel_dyn
= this->rel_dyn_section(layout
);
742 rel_dyn
->add_global(ssym
, elfcpp::R_386_COPY
, dynbss
, offset
);
746 // Optimize the TLS relocation type based on what we know about the
747 // symbol. IS_FINAL is true if the final address of this symbol is
748 // known at link time.
750 tls::Tls_optimization
751 Target_i386::optimize_tls_reloc(bool is_final
, int r_type
)
753 // If we are generating a shared library, then we can't do anything
755 if (parameters
->output_is_shared())
756 return tls::TLSOPT_NONE
;
760 case elfcpp::R_386_TLS_GD
:
761 case elfcpp::R_386_TLS_GOTDESC
:
762 case elfcpp::R_386_TLS_DESC_CALL
:
763 // These are General-Dynamic which permits fully general TLS
764 // access. Since we know that we are generating an executable,
765 // we can convert this to Initial-Exec. If we also know that
766 // this is a local symbol, we can further switch to Local-Exec.
768 return tls::TLSOPT_TO_LE
;
769 return tls::TLSOPT_TO_IE
;
771 case elfcpp::R_386_TLS_LDM
:
772 // This is Local-Dynamic, which refers to a local symbol in the
773 // dynamic TLS block. Since we know that we generating an
774 // executable, we can switch to Local-Exec.
775 return tls::TLSOPT_TO_LE
;
777 case elfcpp::R_386_TLS_LDO_32
:
778 // Another type of Local-Dynamic relocation.
779 return tls::TLSOPT_TO_LE
;
781 case elfcpp::R_386_TLS_IE
:
782 case elfcpp::R_386_TLS_GOTIE
:
783 case elfcpp::R_386_TLS_IE_32
:
784 // These are Initial-Exec relocs which get the thread offset
785 // from the GOT. If we know that we are linking against the
786 // local symbol, we can switch to Local-Exec, which links the
787 // thread offset into the instruction.
789 return tls::TLSOPT_TO_LE
;
790 return tls::TLSOPT_NONE
;
792 case elfcpp::R_386_TLS_LE
:
793 case elfcpp::R_386_TLS_LE_32
:
794 // When we already have Local-Exec, there is nothing further we
796 return tls::TLSOPT_NONE
;
803 // Report an unsupported relocation against a local symbol.
806 Target_i386::Scan::unsupported_reloc_local(Sized_relobj
<32, false>* object
,
809 gold_error(_("%s: unsupported reloc %u against local symbol"),
810 object
->name().c_str(), r_type
);
813 // Scan a relocation for a local symbol.
816 Target_i386::Scan::local(const General_options
&,
817 Symbol_table
* symtab
,
820 Sized_relobj
<32, false>* object
,
821 unsigned int data_shndx
,
822 Output_section
* output_section
,
823 const elfcpp::Rel
<32, false>& reloc
,
825 const elfcpp::Sym
<32, false>& lsym
)
829 case elfcpp::R_386_NONE
:
830 case elfcpp::R_386_GNU_VTINHERIT
:
831 case elfcpp::R_386_GNU_VTENTRY
:
834 case elfcpp::R_386_32
:
835 // If building a shared library (or a position-independent
836 // executable), we need to create a dynamic relocation for
837 // this location. The relocation applied at link time will
838 // apply the link-time value, so we flag the location with
839 // an R_386_RELATIVE relocation so the dynamic loader can
840 // relocate it easily.
841 if (parameters
->output_is_position_independent())
843 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
844 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
845 rel_dyn
->add_local_relative(object
, r_sym
, elfcpp::R_386_RELATIVE
,
846 output_section
, data_shndx
,
847 reloc
.get_r_offset());
851 case elfcpp::R_386_16
:
852 case elfcpp::R_386_8
:
853 // If building a shared library (or a position-independent
854 // executable), we need to create a dynamic relocation for
855 // this location. Because the addend needs to remain in the
856 // data section, we need to be careful not to apply this
857 // relocation statically.
858 if (parameters
->output_is_position_independent())
860 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
861 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
862 rel_dyn
->add_local(object
, r_sym
, r_type
, output_section
, data_shndx
,
863 reloc
.get_r_offset());
867 case elfcpp::R_386_PC32
:
868 case elfcpp::R_386_PC16
:
869 case elfcpp::R_386_PC8
:
872 case elfcpp::R_386_PLT32
:
873 // Since we know this is a local symbol, we can handle this as a
877 case elfcpp::R_386_GOTOFF
:
878 case elfcpp::R_386_GOTPC
:
879 // We need a GOT section.
880 target
->got_section(symtab
, layout
);
883 case elfcpp::R_386_GOT32
:
885 // The symbol requires a GOT entry.
886 Output_data_got
<32, false>* got
= target
->got_section(symtab
, layout
);
887 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
888 if (got
->add_local(object
, r_sym
))
890 // If we are generating a shared object, we need to add a
891 // dynamic RELATIVE relocation for this symbol's GOT entry.
892 if (parameters
->output_is_position_independent())
894 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
895 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
896 rel_dyn
->add_local_relative(object
, r_sym
,
897 elfcpp::R_386_RELATIVE
,
899 object
->local_got_offset(r_sym
));
905 // These are relocations which should only be seen by the
906 // dynamic linker, and should never be seen here.
907 case elfcpp::R_386_COPY
:
908 case elfcpp::R_386_GLOB_DAT
:
909 case elfcpp::R_386_JUMP_SLOT
:
910 case elfcpp::R_386_RELATIVE
:
911 case elfcpp::R_386_TLS_TPOFF
:
912 case elfcpp::R_386_TLS_DTPMOD32
:
913 case elfcpp::R_386_TLS_DTPOFF32
:
914 case elfcpp::R_386_TLS_TPOFF32
:
915 case elfcpp::R_386_TLS_DESC
:
916 gold_error(_("%s: unexpected reloc %u in object file"),
917 object
->name().c_str(), r_type
);
920 // These are initial TLS relocs, which are expected when
922 case elfcpp::R_386_TLS_GD
: // Global-dynamic
923 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
924 case elfcpp::R_386_TLS_DESC_CALL
:
925 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
926 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
927 case elfcpp::R_386_TLS_IE
: // Initial-exec
928 case elfcpp::R_386_TLS_IE_32
:
929 case elfcpp::R_386_TLS_GOTIE
:
930 case elfcpp::R_386_TLS_LE
: // Local-exec
931 case elfcpp::R_386_TLS_LE_32
:
933 bool output_is_shared
= parameters
->output_is_shared();
934 const tls::Tls_optimization optimized_type
935 = Target_i386::optimize_tls_reloc(!output_is_shared
, r_type
);
938 case elfcpp::R_386_TLS_GD
: // Global-dynamic
939 if (optimized_type
== tls::TLSOPT_NONE
)
941 // Create a pair of GOT entries for the module index and
942 // dtv-relative offset.
943 Output_data_got
<32, false>* got
944 = target
->got_section(symtab
, layout
);
945 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
946 got
->add_local_tls_with_rel(object
, r_sym
,
947 lsym
.get_st_shndx(), true,
948 target
->rel_dyn_section(layout
),
949 elfcpp::R_386_TLS_DTPMOD32
);
951 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
952 unsupported_reloc_local(object
, r_type
);
955 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva)
956 case elfcpp::R_386_TLS_DESC_CALL
:
957 // FIXME: If not relaxing to LE, we need to generate
958 // a GOT entry with an R_386_TLS_DESC reloc.
959 if (optimized_type
!= tls::TLSOPT_TO_LE
)
960 unsupported_reloc_local(object
, r_type
);
963 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
964 if (optimized_type
== tls::TLSOPT_NONE
)
966 // Create a GOT entry for the module index.
967 target
->got_mod_index_entry(symtab
, layout
, object
);
969 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
970 unsupported_reloc_local(object
, r_type
);
973 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
976 case elfcpp::R_386_TLS_IE
: // Initial-exec
977 case elfcpp::R_386_TLS_IE_32
:
978 case elfcpp::R_386_TLS_GOTIE
:
979 layout
->set_has_static_tls();
980 if (optimized_type
== tls::TLSOPT_NONE
)
982 // For the R_386_TLS_IE relocation, we need to create a
983 // dynamic relocation when building a shared library.
984 if (r_type
== elfcpp::R_386_TLS_IE
985 && parameters
->output_is_shared())
987 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
989 = elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
990 rel_dyn
->add_local_relative(object
, r_sym
,
991 elfcpp::R_386_RELATIVE
,
992 output_section
, data_shndx
,
993 reloc
.get_r_offset());
995 // Create a GOT entry for the tp-relative offset.
996 Output_data_got
<32, false>* got
997 = target
->got_section(symtab
, layout
);
998 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
999 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_IE_32
1000 ? elfcpp::R_386_TLS_TPOFF32
1001 : elfcpp::R_386_TLS_TPOFF
);
1002 got
->add_local_with_rel(object
, r_sym
,
1003 target
->rel_dyn_section(layout
),
1006 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1007 unsupported_reloc_local(object
, r_type
);
1010 case elfcpp::R_386_TLS_LE
: // Local-exec
1011 case elfcpp::R_386_TLS_LE_32
:
1012 layout
->set_has_static_tls();
1013 if (output_is_shared
)
1015 // We need to create a dynamic relocation.
1016 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1017 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_LE_32
1018 ? elfcpp::R_386_TLS_TPOFF32
1019 : elfcpp::R_386_TLS_TPOFF
);
1020 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1021 rel_dyn
->add_local(object
, r_sym
, dyn_r_type
, output_section
,
1022 data_shndx
, reloc
.get_r_offset());
1032 case elfcpp::R_386_32PLT
:
1033 case elfcpp::R_386_TLS_GD_32
:
1034 case elfcpp::R_386_TLS_GD_PUSH
:
1035 case elfcpp::R_386_TLS_GD_CALL
:
1036 case elfcpp::R_386_TLS_GD_POP
:
1037 case elfcpp::R_386_TLS_LDM_32
:
1038 case elfcpp::R_386_TLS_LDM_PUSH
:
1039 case elfcpp::R_386_TLS_LDM_CALL
:
1040 case elfcpp::R_386_TLS_LDM_POP
:
1041 case elfcpp::R_386_USED_BY_INTEL_200
:
1043 unsupported_reloc_local(object
, r_type
);
1048 // Report an unsupported relocation against a global symbol.
1051 Target_i386::Scan::unsupported_reloc_global(Sized_relobj
<32, false>* object
,
1052 unsigned int r_type
,
1055 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
1056 object
->name().c_str(), r_type
, gsym
->demangled_name().c_str());
1059 // Scan a relocation for a global symbol.
1062 Target_i386::Scan::global(const General_options
& options
,
1063 Symbol_table
* symtab
,
1065 Target_i386
* target
,
1066 Sized_relobj
<32, false>* object
,
1067 unsigned int data_shndx
,
1068 Output_section
* output_section
,
1069 const elfcpp::Rel
<32, false>& reloc
,
1070 unsigned int r_type
,
1075 case elfcpp::R_386_NONE
:
1076 case elfcpp::R_386_GNU_VTINHERIT
:
1077 case elfcpp::R_386_GNU_VTENTRY
:
1080 case elfcpp::R_386_32
:
1081 case elfcpp::R_386_16
:
1082 case elfcpp::R_386_8
:
1084 // Make a PLT entry if necessary.
1085 if (gsym
->needs_plt_entry())
1087 target
->make_plt_entry(symtab
, layout
, gsym
);
1088 // Since this is not a PC-relative relocation, we may be
1089 // taking the address of a function. In that case we need to
1090 // set the entry in the dynamic symbol table to the address of
1092 if (gsym
->is_from_dynobj() && !parameters
->output_is_shared())
1093 gsym
->set_needs_dynsym_value();
1095 // Make a dynamic relocation if necessary.
1096 if (gsym
->needs_dynamic_reloc(Symbol::ABSOLUTE_REF
))
1098 if (target
->may_need_copy_reloc(gsym
))
1100 target
->copy_reloc(&options
, symtab
, layout
, object
,
1101 data_shndx
, output_section
, gsym
, reloc
);
1103 else if (r_type
== elfcpp::R_386_32
1104 && gsym
->can_use_relative_reloc(false))
1106 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1107 rel_dyn
->add_global_relative(gsym
, elfcpp::R_386_RELATIVE
,
1108 output_section
, object
,
1109 data_shndx
, reloc
.get_r_offset());
1113 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1114 rel_dyn
->add_global(gsym
, r_type
, output_section
, object
,
1115 data_shndx
, reloc
.get_r_offset());
1121 case elfcpp::R_386_PC32
:
1122 case elfcpp::R_386_PC16
:
1123 case elfcpp::R_386_PC8
:
1125 // Make a PLT entry if necessary.
1126 if (gsym
->needs_plt_entry())
1128 // These relocations are used for function calls only in
1129 // non-PIC code. For a 32-bit relocation in a shared library,
1130 // we'll need a text relocation anyway, so we can skip the
1131 // PLT entry and let the dynamic linker bind the call directly
1132 // to the target. For smaller relocations, we should use a
1133 // PLT entry to ensure that the call can reach.
1134 if (!parameters
->output_is_shared()
1135 || r_type
!= elfcpp::R_386_PC32
)
1136 target
->make_plt_entry(symtab
, layout
, gsym
);
1138 // Make a dynamic relocation if necessary.
1139 int flags
= Symbol::NON_PIC_REF
;
1140 if (gsym
->type() == elfcpp::STT_FUNC
)
1141 flags
|= Symbol::FUNCTION_CALL
;
1142 if (gsym
->needs_dynamic_reloc(flags
))
1144 if (target
->may_need_copy_reloc(gsym
))
1146 target
->copy_reloc(&options
, symtab
, layout
, object
,
1147 data_shndx
, output_section
, gsym
, reloc
);
1151 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1152 rel_dyn
->add_global(gsym
, r_type
, output_section
, object
,
1153 data_shndx
, reloc
.get_r_offset());
1159 case elfcpp::R_386_GOT32
:
1161 // The symbol requires a GOT entry.
1162 Output_data_got
<32, false>* got
= target
->got_section(symtab
, layout
);
1163 if (gsym
->final_value_is_known())
1164 got
->add_global(gsym
);
1167 // If this symbol is not fully resolved, we need to add a
1168 // GOT entry with a dynamic relocation.
1169 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1170 if (gsym
->is_from_dynobj() || gsym
->is_preemptible())
1171 got
->add_global_with_rel(gsym
, rel_dyn
, elfcpp::R_386_GLOB_DAT
);
1174 if (got
->add_global(gsym
))
1175 rel_dyn
->add_global_relative(gsym
, elfcpp::R_386_RELATIVE
,
1176 got
, gsym
->got_offset());
1182 case elfcpp::R_386_PLT32
:
1183 // If the symbol is fully resolved, this is just a PC32 reloc.
1184 // Otherwise we need a PLT entry.
1185 if (gsym
->final_value_is_known())
1187 // If building a shared library, we can also skip the PLT entry
1188 // if the symbol is defined in the output file and is protected
1190 if (gsym
->is_defined()
1191 && !gsym
->is_from_dynobj()
1192 && !gsym
->is_preemptible())
1194 target
->make_plt_entry(symtab
, layout
, gsym
);
1197 case elfcpp::R_386_GOTOFF
:
1198 case elfcpp::R_386_GOTPC
:
1199 // We need a GOT section.
1200 target
->got_section(symtab
, layout
);
1203 // These are relocations which should only be seen by the
1204 // dynamic linker, and should never be seen here.
1205 case elfcpp::R_386_COPY
:
1206 case elfcpp::R_386_GLOB_DAT
:
1207 case elfcpp::R_386_JUMP_SLOT
:
1208 case elfcpp::R_386_RELATIVE
:
1209 case elfcpp::R_386_TLS_TPOFF
:
1210 case elfcpp::R_386_TLS_DTPMOD32
:
1211 case elfcpp::R_386_TLS_DTPOFF32
:
1212 case elfcpp::R_386_TLS_TPOFF32
:
1213 case elfcpp::R_386_TLS_DESC
:
1214 gold_error(_("%s: unexpected reloc %u in object file"),
1215 object
->name().c_str(), r_type
);
1218 // These are initial tls relocs, which are expected when
1220 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1221 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
1222 case elfcpp::R_386_TLS_DESC_CALL
:
1223 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1224 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1225 case elfcpp::R_386_TLS_IE
: // Initial-exec
1226 case elfcpp::R_386_TLS_IE_32
:
1227 case elfcpp::R_386_TLS_GOTIE
:
1228 case elfcpp::R_386_TLS_LE
: // Local-exec
1229 case elfcpp::R_386_TLS_LE_32
:
1231 const bool is_final
= gsym
->final_value_is_known();
1232 const tls::Tls_optimization optimized_type
1233 = Target_i386::optimize_tls_reloc(is_final
, r_type
);
1236 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1237 if (optimized_type
== tls::TLSOPT_NONE
)
1239 // Create a pair of GOT entries for the module index and
1240 // dtv-relative offset.
1241 Output_data_got
<32, false>* got
1242 = target
->got_section(symtab
, layout
);
1243 got
->add_global_tls_with_rel(gsym
,
1244 target
->rel_dyn_section(layout
),
1245 elfcpp::R_386_TLS_DTPMOD32
,
1246 elfcpp::R_386_TLS_DTPOFF32
);
1248 else if (optimized_type
== tls::TLSOPT_TO_IE
)
1250 // Create a GOT entry for the tp-relative offset.
1251 Output_data_got
<32, false>* got
1252 = target
->got_section(symtab
, layout
);
1253 got
->add_global_with_rel(gsym
, target
->rel_dyn_section(layout
),
1254 elfcpp::R_386_TLS_TPOFF32
);
1256 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1257 unsupported_reloc_global(object
, r_type
, gsym
);
1260 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (~oliva url)
1261 case elfcpp::R_386_TLS_DESC_CALL
:
1262 // FIXME: If not relaxing to LE, we need to generate
1263 // a GOT entry with an R_386_TLS_DESC reloc.
1264 if (optimized_type
!= tls::TLSOPT_TO_LE
)
1265 unsupported_reloc_global(object
, r_type
, gsym
);
1266 unsupported_reloc_global(object
, r_type
, gsym
);
1269 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1270 if (optimized_type
== tls::TLSOPT_NONE
)
1272 // Create a GOT entry for the module index.
1273 target
->got_mod_index_entry(symtab
, layout
, object
);
1275 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1276 unsupported_reloc_global(object
, r_type
, gsym
);
1279 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1282 case elfcpp::R_386_TLS_IE
: // Initial-exec
1283 case elfcpp::R_386_TLS_IE_32
:
1284 case elfcpp::R_386_TLS_GOTIE
:
1285 layout
->set_has_static_tls();
1286 if (optimized_type
== tls::TLSOPT_NONE
)
1288 // For the R_386_TLS_IE relocation, we need to create a
1289 // dynamic relocation when building a shared library.
1290 if (r_type
== elfcpp::R_386_TLS_IE
1291 && parameters
->output_is_shared())
1293 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1294 rel_dyn
->add_global_relative(gsym
, elfcpp::R_386_RELATIVE
,
1295 output_section
, object
,
1297 reloc
.get_r_offset());
1299 // Create a GOT entry for the tp-relative offset.
1300 Output_data_got
<32, false>* got
1301 = target
->got_section(symtab
, layout
);
1302 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_IE_32
1303 ? elfcpp::R_386_TLS_TPOFF32
1304 : elfcpp::R_386_TLS_TPOFF
);
1305 got
->add_global_with_rel(gsym
,
1306 target
->rel_dyn_section(layout
),
1309 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1310 unsupported_reloc_global(object
, r_type
, gsym
);
1313 case elfcpp::R_386_TLS_LE
: // Local-exec
1314 case elfcpp::R_386_TLS_LE_32
:
1315 layout
->set_has_static_tls();
1316 if (parameters
->output_is_shared())
1318 // We need to create a dynamic relocation.
1319 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_LE_32
1320 ? elfcpp::R_386_TLS_TPOFF32
1321 : elfcpp::R_386_TLS_TPOFF
);
1322 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1323 rel_dyn
->add_global(gsym
, dyn_r_type
, output_section
, object
,
1324 data_shndx
, reloc
.get_r_offset());
1334 case elfcpp::R_386_32PLT
:
1335 case elfcpp::R_386_TLS_GD_32
:
1336 case elfcpp::R_386_TLS_GD_PUSH
:
1337 case elfcpp::R_386_TLS_GD_CALL
:
1338 case elfcpp::R_386_TLS_GD_POP
:
1339 case elfcpp::R_386_TLS_LDM_32
:
1340 case elfcpp::R_386_TLS_LDM_PUSH
:
1341 case elfcpp::R_386_TLS_LDM_CALL
:
1342 case elfcpp::R_386_TLS_LDM_POP
:
1343 case elfcpp::R_386_USED_BY_INTEL_200
:
1345 unsupported_reloc_global(object
, r_type
, gsym
);
1350 // Scan relocations for a section.
1353 Target_i386::scan_relocs(const General_options
& options
,
1354 Symbol_table
* symtab
,
1356 Sized_relobj
<32, false>* object
,
1357 unsigned int data_shndx
,
1358 unsigned int sh_type
,
1359 const unsigned char* prelocs
,
1361 Output_section
* output_section
,
1362 bool needs_special_offset_handling
,
1363 size_t local_symbol_count
,
1364 const unsigned char* plocal_symbols
)
1366 if (sh_type
== elfcpp::SHT_RELA
)
1368 gold_error(_("%s: unsupported RELA reloc section"),
1369 object
->name().c_str());
1373 gold::scan_relocs
<32, false, Target_i386
, elfcpp::SHT_REL
,
1384 needs_special_offset_handling
,
1389 // Finalize the sections.
1392 Target_i386::do_finalize_sections(Layout
* layout
)
1394 // Fill in some more dynamic tags.
1395 Output_data_dynamic
* const odyn
= layout
->dynamic_data();
1398 if (this->got_plt_
!= NULL
)
1399 odyn
->add_section_address(elfcpp::DT_PLTGOT
, this->got_plt_
);
1401 if (this->plt_
!= NULL
)
1403 const Output_data
* od
= this->plt_
->rel_plt();
1404 odyn
->add_section_size(elfcpp::DT_PLTRELSZ
, od
);
1405 odyn
->add_section_address(elfcpp::DT_JMPREL
, od
);
1406 odyn
->add_constant(elfcpp::DT_PLTREL
, elfcpp::DT_REL
);
1409 if (this->rel_dyn_
!= NULL
)
1411 const Output_data
* od
= this->rel_dyn_
;
1412 odyn
->add_section_address(elfcpp::DT_REL
, od
);
1413 odyn
->add_section_size(elfcpp::DT_RELSZ
, od
);
1414 odyn
->add_constant(elfcpp::DT_RELENT
,
1415 elfcpp::Elf_sizes
<32>::rel_size
);
1418 if (!parameters
->output_is_shared())
1420 // The value of the DT_DEBUG tag is filled in by the dynamic
1421 // linker at run time, and used by the debugger.
1422 odyn
->add_constant(elfcpp::DT_DEBUG
, 0);
1426 // Emit any relocs we saved in an attempt to avoid generating COPY
1428 if (this->copy_relocs_
== NULL
)
1430 if (this->copy_relocs_
->any_to_emit())
1432 Reloc_section
* rel_dyn
= this->rel_dyn_section(layout
);
1433 this->copy_relocs_
->emit(rel_dyn
);
1435 delete this->copy_relocs_
;
1436 this->copy_relocs_
= NULL
;
1439 // Return whether a direct absolute static relocation needs to be applied.
1440 // In cases where Scan::local() or Scan::global() has created
1441 // a dynamic relocation other than R_386_RELATIVE, the addend
1442 // of the relocation is carried in the data, and we must not
1443 // apply the static relocation.
1446 Target_i386::Relocate::should_apply_static_reloc(const Sized_symbol
<32>* gsym
,
1450 // For local symbols, we will have created a non-RELATIVE dynamic
1451 // relocation only if (a) the output is position independent,
1452 // (b) the relocation is absolute (not pc- or segment-relative), and
1453 // (c) the relocation is not 32 bits wide.
1455 return !(parameters
->output_is_position_independent()
1456 && (ref_flags
& Symbol::ABSOLUTE_REF
)
1459 // For global symbols, we use the same helper routines used in the
1460 // scan pass. If we did not create a dynamic relocation, or if we
1461 // created a RELATIVE dynamic relocation, we should apply the static
1463 bool has_dyn
= gsym
->needs_dynamic_reloc(ref_flags
);
1464 bool is_rel
= (ref_flags
& Symbol::ABSOLUTE_REF
)
1465 && gsym
->can_use_relative_reloc(ref_flags
1466 & Symbol::FUNCTION_CALL
);
1467 return !has_dyn
|| is_rel
;
1470 // Perform a relocation.
1473 Target_i386::Relocate::relocate(const Relocate_info
<32, false>* relinfo
,
1474 Target_i386
* target
,
1476 const elfcpp::Rel
<32, false>& rel
,
1477 unsigned int r_type
,
1478 const Sized_symbol
<32>* gsym
,
1479 const Symbol_value
<32>* psymval
,
1480 unsigned char* view
,
1481 elfcpp::Elf_types
<32>::Elf_Addr address
,
1482 section_size_type view_size
)
1484 if (this->skip_call_tls_get_addr_
)
1486 if (r_type
!= elfcpp::R_386_PLT32
1488 || strcmp(gsym
->name(), "___tls_get_addr") != 0)
1489 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
1490 _("missing expected TLS relocation"));
1493 this->skip_call_tls_get_addr_
= false;
1498 // Pick the value to use for symbols defined in shared objects.
1499 Symbol_value
<32> symval
;
1500 bool is_nonpic
= (r_type
== elfcpp::R_386_PC8
1501 || r_type
== elfcpp::R_386_PC16
1502 || r_type
== elfcpp::R_386_PC32
);
1504 && (gsym
->is_from_dynobj()
1505 || (parameters
->output_is_shared()
1506 && gsym
->is_preemptible()))
1507 && gsym
->has_plt_offset()
1508 && (!is_nonpic
|| !parameters
->output_is_shared()))
1510 symval
.set_output_value(target
->plt_section()->address()
1511 + gsym
->plt_offset());
1515 const Sized_relobj
<32, false>* object
= relinfo
->object
;
1517 // Get the GOT offset if needed.
1518 // The GOT pointer points to the end of the GOT section.
1519 // We need to subtract the size of the GOT section to get
1520 // the actual offset to use in the relocation.
1521 bool have_got_offset
= false;
1522 unsigned int got_offset
= 0;
1525 case elfcpp::R_386_GOT32
:
1528 gold_assert(gsym
->has_got_offset());
1529 got_offset
= gsym
->got_offset() - target
->got_size();
1533 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
1534 gold_assert(object
->local_has_got_offset(r_sym
));
1535 got_offset
= object
->local_got_offset(r_sym
) - target
->got_size();
1537 have_got_offset
= true;
1546 case elfcpp::R_386_NONE
:
1547 case elfcpp::R_386_GNU_VTINHERIT
:
1548 case elfcpp::R_386_GNU_VTENTRY
:
1551 case elfcpp::R_386_32
:
1552 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, true))
1553 Relocate_functions
<32, false>::rel32(view
, object
, psymval
);
1556 case elfcpp::R_386_PC32
:
1558 int ref_flags
= Symbol::NON_PIC_REF
;
1559 if (gsym
!= NULL
&& gsym
->type() == elfcpp::STT_FUNC
)
1560 ref_flags
|= Symbol::FUNCTION_CALL
;
1561 if (should_apply_static_reloc(gsym
, ref_flags
, true))
1562 Relocate_functions
<32, false>::pcrel32(view
, object
, psymval
, address
);
1566 case elfcpp::R_386_16
:
1567 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, false))
1568 Relocate_functions
<32, false>::rel16(view
, object
, psymval
);
1571 case elfcpp::R_386_PC16
:
1573 int ref_flags
= Symbol::NON_PIC_REF
;
1574 if (gsym
!= NULL
&& gsym
->type() == elfcpp::STT_FUNC
)
1575 ref_flags
|= Symbol::FUNCTION_CALL
;
1576 if (should_apply_static_reloc(gsym
, ref_flags
, false))
1577 Relocate_functions
<32, false>::pcrel32(view
, object
, psymval
, address
);
1581 case elfcpp::R_386_8
:
1582 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, false))
1583 Relocate_functions
<32, false>::rel8(view
, object
, psymval
);
1586 case elfcpp::R_386_PC8
:
1588 int ref_flags
= Symbol::NON_PIC_REF
;
1589 if (gsym
!= NULL
&& gsym
->type() == elfcpp::STT_FUNC
)
1590 ref_flags
|= Symbol::FUNCTION_CALL
;
1591 if (should_apply_static_reloc(gsym
, ref_flags
, false))
1592 Relocate_functions
<32, false>::pcrel32(view
, object
, psymval
, address
);
1596 case elfcpp::R_386_PLT32
:
1597 gold_assert(gsym
== NULL
1598 || gsym
->has_plt_offset()
1599 || gsym
->final_value_is_known()
1600 || (gsym
->is_defined()
1601 && !gsym
->is_from_dynobj()
1602 && !gsym
->is_preemptible()));
1603 Relocate_functions
<32, false>::pcrel32(view
, object
, psymval
, address
);
1606 case elfcpp::R_386_GOT32
:
1607 gold_assert(have_got_offset
);
1608 Relocate_functions
<32, false>::rel32(view
, got_offset
);
1611 case elfcpp::R_386_GOTOFF
:
1613 elfcpp::Elf_types
<32>::Elf_Addr value
;
1614 value
= (psymval
->value(object
, 0)
1615 - target
->got_plt_section()->address());
1616 Relocate_functions
<32, false>::rel32(view
, value
);
1620 case elfcpp::R_386_GOTPC
:
1622 elfcpp::Elf_types
<32>::Elf_Addr value
;
1623 value
= target
->got_plt_section()->address();
1624 Relocate_functions
<32, false>::pcrel32(view
, value
, address
);
1628 case elfcpp::R_386_COPY
:
1629 case elfcpp::R_386_GLOB_DAT
:
1630 case elfcpp::R_386_JUMP_SLOT
:
1631 case elfcpp::R_386_RELATIVE
:
1632 // These are outstanding tls relocs, which are unexpected when
1634 case elfcpp::R_386_TLS_TPOFF
:
1635 case elfcpp::R_386_TLS_DTPMOD32
:
1636 case elfcpp::R_386_TLS_DTPOFF32
:
1637 case elfcpp::R_386_TLS_TPOFF32
:
1638 case elfcpp::R_386_TLS_DESC
:
1639 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
1640 _("unexpected reloc %u in object file"),
1644 // These are initial tls relocs, which are expected when
1646 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1647 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
1648 case elfcpp::R_386_TLS_DESC_CALL
:
1649 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1650 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1651 case elfcpp::R_386_TLS_IE
: // Initial-exec
1652 case elfcpp::R_386_TLS_IE_32
:
1653 case elfcpp::R_386_TLS_GOTIE
:
1654 case elfcpp::R_386_TLS_LE
: // Local-exec
1655 case elfcpp::R_386_TLS_LE_32
:
1656 this->relocate_tls(relinfo
, target
, relnum
, rel
, r_type
, gsym
, psymval
,
1657 view
, address
, view_size
);
1660 case elfcpp::R_386_32PLT
:
1661 case elfcpp::R_386_TLS_GD_32
:
1662 case elfcpp::R_386_TLS_GD_PUSH
:
1663 case elfcpp::R_386_TLS_GD_CALL
:
1664 case elfcpp::R_386_TLS_GD_POP
:
1665 case elfcpp::R_386_TLS_LDM_32
:
1666 case elfcpp::R_386_TLS_LDM_PUSH
:
1667 case elfcpp::R_386_TLS_LDM_CALL
:
1668 case elfcpp::R_386_TLS_LDM_POP
:
1669 case elfcpp::R_386_USED_BY_INTEL_200
:
1671 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
1672 _("unsupported reloc %u"),
1680 // Perform a TLS relocation.
1683 Target_i386::Relocate::relocate_tls(const Relocate_info
<32, false>* relinfo
,
1684 Target_i386
* target
,
1686 const elfcpp::Rel
<32, false>& rel
,
1687 unsigned int r_type
,
1688 const Sized_symbol
<32>* gsym
,
1689 const Symbol_value
<32>* psymval
,
1690 unsigned char* view
,
1691 elfcpp::Elf_types
<32>::Elf_Addr
,
1692 section_size_type view_size
)
1694 Output_segment
* tls_segment
= relinfo
->layout
->tls_segment();
1696 const Sized_relobj
<32, false>* object
= relinfo
->object
;
1698 elfcpp::Elf_types
<32>::Elf_Addr value
= psymval
->value(object
, 0);
1700 const bool is_final
= (gsym
== NULL
1701 ? !parameters
->output_is_position_independent()
1702 : gsym
->final_value_is_known());
1703 const tls::Tls_optimization optimized_type
1704 = Target_i386::optimize_tls_reloc(is_final
, r_type
);
1707 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1708 if (optimized_type
== tls::TLSOPT_TO_LE
)
1710 gold_assert(tls_segment
!= NULL
);
1711 this->tls_gd_to_le(relinfo
, relnum
, tls_segment
,
1712 rel
, r_type
, value
, view
,
1718 unsigned int got_offset
;
1721 gold_assert(gsym
->has_tls_got_offset(true));
1722 got_offset
= gsym
->tls_got_offset(true) - target
->got_size();
1726 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
1727 gold_assert(object
->local_has_tls_got_offset(r_sym
, true));
1728 got_offset
= (object
->local_tls_got_offset(r_sym
, true)
1729 - target
->got_size());
1731 if (optimized_type
== tls::TLSOPT_TO_IE
)
1733 gold_assert(tls_segment
!= NULL
);
1734 this->tls_gd_to_ie(relinfo
, relnum
, tls_segment
, rel
, r_type
,
1735 got_offset
, view
, view_size
);
1738 else if (optimized_type
== tls::TLSOPT_NONE
)
1740 // Relocate the field with the offset of the pair of GOT
1742 Relocate_functions
<32, false>::rel32(view
, got_offset
);
1746 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
1747 _("unsupported reloc %u"),
1751 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
1752 case elfcpp::R_386_TLS_DESC_CALL
:
1753 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
1754 _("unsupported reloc %u"),
1758 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1759 if (this->local_dynamic_type_
== LOCAL_DYNAMIC_SUN
)
1761 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
1762 _("both SUN and GNU model "
1763 "TLS relocations"));
1766 this->local_dynamic_type_
= LOCAL_DYNAMIC_GNU
;
1767 if (optimized_type
== tls::TLSOPT_TO_LE
)
1769 gold_assert(tls_segment
!= NULL
);
1770 this->tls_ld_to_le(relinfo
, relnum
, tls_segment
, rel
, r_type
,
1771 value
, view
, view_size
);
1774 else if (optimized_type
== tls::TLSOPT_NONE
)
1776 // Relocate the field with the offset of the GOT entry for
1777 // the module index.
1778 unsigned int got_offset
;
1779 got_offset
= (target
->got_mod_index_entry(NULL
, NULL
, NULL
)
1780 - target
->got_size());
1781 Relocate_functions
<32, false>::rel32(view
, got_offset
);
1784 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
1785 _("unsupported reloc %u"),
1789 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1790 // This reloc can appear in debugging sections, in which case we
1791 // won't see the TLS_LDM reloc. The local_dynamic_type field
1793 if (optimized_type
== tls::TLSOPT_TO_LE
)
1795 gold_assert(tls_segment
!= NULL
);
1796 value
-= tls_segment
->memsz();
1798 Relocate_functions
<32, false>::rel32(view
, value
);
1801 case elfcpp::R_386_TLS_IE
: // Initial-exec
1802 case elfcpp::R_386_TLS_GOTIE
:
1803 case elfcpp::R_386_TLS_IE_32
:
1804 if (optimized_type
== tls::TLSOPT_TO_LE
)
1806 gold_assert(tls_segment
!= NULL
);
1807 Target_i386::Relocate::tls_ie_to_le(relinfo
, relnum
, tls_segment
,
1808 rel
, r_type
, value
, view
,
1812 else if (optimized_type
== tls::TLSOPT_NONE
)
1814 // Relocate the field with the offset of the GOT entry for
1815 // the tp-relative offset of the symbol.
1816 unsigned int got_offset
;
1819 gold_assert(gsym
->has_got_offset());
1820 got_offset
= gsym
->got_offset();
1824 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
1825 gold_assert(object
->local_has_got_offset(r_sym
));
1826 got_offset
= object
->local_got_offset(r_sym
);
1828 // For the R_386_TLS_IE relocation, we need to apply the
1829 // absolute address of the GOT entry.
1830 if (r_type
== elfcpp::R_386_TLS_IE
)
1831 got_offset
+= target
->got_plt_section()->address();
1832 // All GOT offsets are relative to the end of the GOT.
1833 got_offset
-= target
->got_size();
1834 Relocate_functions
<32, false>::rel32(view
, got_offset
);
1837 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
1838 _("unsupported reloc %u"),
1842 case elfcpp::R_386_TLS_LE
: // Local-exec
1843 // If we're creating a shared library, a dynamic relocation will
1844 // have been created for this location, so do not apply it now.
1845 if (!parameters
->output_is_shared())
1847 gold_assert(tls_segment
!= NULL
);
1848 value
-= tls_segment
->memsz();
1849 Relocate_functions
<32, false>::rel32(view
, value
);
1853 case elfcpp::R_386_TLS_LE_32
:
1854 // If we're creating a shared library, a dynamic relocation will
1855 // have been created for this location, so do not apply it now.
1856 if (!parameters
->output_is_shared())
1858 gold_assert(tls_segment
!= NULL
);
1859 value
= tls_segment
->memsz() - value
;
1860 Relocate_functions
<32, false>::rel32(view
, value
);
1866 // Do a relocation in which we convert a TLS General-Dynamic to a
1870 Target_i386::Relocate::tls_gd_to_le(const Relocate_info
<32, false>* relinfo
,
1872 Output_segment
* tls_segment
,
1873 const elfcpp::Rel
<32, false>& rel
,
1875 elfcpp::Elf_types
<32>::Elf_Addr value
,
1876 unsigned char* view
,
1877 section_size_type view_size
)
1879 // leal foo(,%reg,1),%eax; call ___tls_get_addr
1880 // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
1881 // leal foo(%reg),%eax; call ___tls_get_addr
1882 // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
1884 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
1885 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 9);
1887 unsigned char op1
= view
[-1];
1888 unsigned char op2
= view
[-2];
1890 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
1891 op2
== 0x8d || op2
== 0x04);
1892 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[4] == 0xe8);
1898 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -3);
1899 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[-3] == 0x8d);
1900 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
1901 ((op1
& 0xc7) == 0x05 && op1
!= (4 << 3)));
1902 memcpy(view
- 3, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
1906 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
1907 (op1
& 0xf8) == 0x80 && (op1
& 7) != 4);
1908 if (rel
.get_r_offset() + 9 < view_size
1911 // There is a trailing nop. Use the size byte subl.
1912 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
1917 // Use the five byte subl.
1918 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
1922 value
= tls_segment
->memsz() - value
;
1923 Relocate_functions
<32, false>::rel32(view
+ roff
, value
);
1925 // The next reloc should be a PLT32 reloc against __tls_get_addr.
1927 this->skip_call_tls_get_addr_
= true;
1930 // Do a relocation in which we convert a TLS General-Dynamic to an
1934 Target_i386::Relocate::tls_gd_to_ie(const Relocate_info
<32, false>* relinfo
,
1936 Output_segment
* tls_segment
,
1937 const elfcpp::Rel
<32, false>& rel
,
1939 elfcpp::Elf_types
<32>::Elf_Addr value
,
1940 unsigned char* view
,
1941 section_size_type view_size
)
1943 // leal foo(,%ebx,1),%eax; call ___tls_get_addr
1944 // ==> movl %gs:0,%eax; addl foo@gotntpoff(%ebx),%eax
1946 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
1947 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 9);
1949 unsigned char op1
= view
[-1];
1950 unsigned char op2
= view
[-2];
1952 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
1953 op2
== 0x8d || op2
== 0x04);
1954 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[4] == 0xe8);
1958 // FIXME: For now, support only one form.
1959 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
1960 op1
== 0x8d && op2
== 0x04);
1964 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -3);
1965 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[-3] == 0x8d);
1966 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
1967 ((op1
& 0xc7) == 0x05 && op1
!= (4 << 3)));
1968 memcpy(view
- 3, "\x65\xa1\0\0\0\0\x03\x83\0\0\0", 12);
1972 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
1973 (op1
& 0xf8) == 0x80 && (op1
& 7) != 4);
1974 if (rel
.get_r_offset() + 9 < view_size
1977 // FIXME: This is not the right instruction sequence.
1978 // There is a trailing nop. Use the size byte subl.
1979 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
1984 // FIXME: This is not the right instruction sequence.
1985 // Use the five byte subl.
1986 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
1990 value
= tls_segment
->memsz() - value
;
1991 Relocate_functions
<32, false>::rel32(view
+ roff
, value
);
1993 // The next reloc should be a PLT32 reloc against __tls_get_addr.
1995 this->skip_call_tls_get_addr_
= true;
1998 // Do a relocation in which we convert a TLS Local-Dynamic to a
2002 Target_i386::Relocate::tls_ld_to_le(const Relocate_info
<32, false>* relinfo
,
2005 const elfcpp::Rel
<32, false>& rel
,
2007 elfcpp::Elf_types
<32>::Elf_Addr
,
2008 unsigned char* view
,
2009 section_size_type view_size
)
2011 // leal foo(%reg), %eax; call ___tls_get_addr
2012 // ==> movl %gs:0,%eax; nop; leal 0(%esi,1),%esi
2014 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2015 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 9);
2017 // FIXME: Does this test really always pass?
2018 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2019 view
[-2] == 0x8d && view
[-1] == 0x83);
2021 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[4] == 0xe8);
2023 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x90\x8d\x74\x26\0", 11);
2025 // The next reloc should be a PLT32 reloc against __tls_get_addr.
2027 this->skip_call_tls_get_addr_
= true;
2030 // Do a relocation in which we convert a TLS Initial-Exec to a
2034 Target_i386::Relocate::tls_ie_to_le(const Relocate_info
<32, false>* relinfo
,
2036 Output_segment
* tls_segment
,
2037 const elfcpp::Rel
<32, false>& rel
,
2038 unsigned int r_type
,
2039 elfcpp::Elf_types
<32>::Elf_Addr value
,
2040 unsigned char* view
,
2041 section_size_type view_size
)
2043 // We have to actually change the instructions, which means that we
2044 // need to examine the opcodes to figure out which instruction we
2046 if (r_type
== elfcpp::R_386_TLS_IE
)
2048 // movl %gs:XX,%eax ==> movl $YY,%eax
2049 // movl %gs:XX,%reg ==> movl $YY,%reg
2050 // addl %gs:XX,%reg ==> addl $YY,%reg
2051 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -1);
2052 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
2054 unsigned char op1
= view
[-1];
2057 // movl XX,%eax ==> movl $YY,%eax
2062 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2064 unsigned char op2
= view
[-2];
2067 // movl XX,%reg ==> movl $YY,%reg
2068 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2069 (op1
& 0xc7) == 0x05);
2071 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
2073 else if (op2
== 0x03)
2075 // addl XX,%reg ==> addl $YY,%reg
2076 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2077 (op1
& 0xc7) == 0x05);
2079 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
2082 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), 0);
2087 // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2
2088 // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2
2089 // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2
2090 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2091 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
2093 unsigned char op1
= view
[-1];
2094 unsigned char op2
= view
[-2];
2095 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2096 (op1
& 0xc0) == 0x80 && (op1
& 7) != 4);
2099 // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2
2101 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
2103 else if (op2
== 0x2b)
2105 // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2
2107 view
[-1] = 0xe8 | ((op1
>> 3) & 7);
2109 else if (op2
== 0x03)
2111 // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2
2113 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
2116 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), 0);
2119 value
= tls_segment
->memsz() - value
;
2120 if (r_type
== elfcpp::R_386_TLS_IE
|| r_type
== elfcpp::R_386_TLS_GOTIE
)
2123 Relocate_functions
<32, false>::rel32(view
, value
);
2126 // Relocate section data.
2129 Target_i386::relocate_section(const Relocate_info
<32, false>* relinfo
,
2130 unsigned int sh_type
,
2131 const unsigned char* prelocs
,
2133 Output_section
* output_section
,
2134 bool needs_special_offset_handling
,
2135 unsigned char* view
,
2136 elfcpp::Elf_types
<32>::Elf_Addr address
,
2137 section_size_type view_size
)
2139 gold_assert(sh_type
== elfcpp::SHT_REL
);
2141 gold::relocate_section
<32, false, Target_i386
, elfcpp::SHT_REL
,
2142 Target_i386::Relocate
>(
2148 needs_special_offset_handling
,
2154 // Return the value to use for a dynamic which requires special
2155 // treatment. This is how we support equality comparisons of function
2156 // pointers across shared library boundaries, as described in the
2157 // processor specific ABI supplement.
2160 Target_i386::do_dynsym_value(const Symbol
* gsym
) const
2162 gold_assert(gsym
->is_from_dynobj() && gsym
->has_plt_offset());
2163 return this->plt_section()->address() + gsym
->plt_offset();
2166 // Return a string used to fill a code section with nops to take up
2167 // the specified length.
2170 Target_i386::do_code_fill(section_size_type length
)
2174 // Build a jmp instruction to skip over the bytes.
2175 unsigned char jmp
[5];
2177 elfcpp::Swap_unaligned
<32, false>::writeval(jmp
+ 1, length
- 5);
2178 return (std::string(reinterpret_cast<char*>(&jmp
[0]), 5)
2179 + std::string(length
- 5, '\0'));
2182 // Nop sequences of various lengths.
2183 const char nop1
[1] = { 0x90 }; // nop
2184 const char nop2
[2] = { 0x66, 0x90 }; // xchg %ax %ax
2185 const char nop3
[3] = { 0x8d, 0x76, 0x00 }; // leal 0(%esi),%esi
2186 const char nop4
[4] = { 0x8d, 0x74, 0x26, 0x00}; // leal 0(%esi,1),%esi
2187 const char nop5
[5] = { 0x90, 0x8d, 0x74, 0x26, // nop
2188 0x00 }; // leal 0(%esi,1),%esi
2189 const char nop6
[6] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2191 const char nop7
[7] = { 0x8d, 0xb4, 0x26, 0x00, // leal 0L(%esi,1),%esi
2193 const char nop8
[8] = { 0x90, 0x8d, 0xb4, 0x26, // nop
2194 0x00, 0x00, 0x00, 0x00 }; // leal 0L(%esi,1),%esi
2195 const char nop9
[9] = { 0x89, 0xf6, 0x8d, 0xbc, // movl %esi,%esi
2196 0x27, 0x00, 0x00, 0x00, // leal 0L(%edi,1),%edi
2198 const char nop10
[10] = { 0x8d, 0x76, 0x00, 0x8d, // leal 0(%esi),%esi
2199 0xbc, 0x27, 0x00, 0x00, // leal 0L(%edi,1),%edi
2201 const char nop11
[11] = { 0x8d, 0x74, 0x26, 0x00, // leal 0(%esi,1),%esi
2202 0x8d, 0xbc, 0x27, 0x00, // leal 0L(%edi,1),%edi
2204 const char nop12
[12] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2205 0x00, 0x00, 0x8d, 0xbf, // leal 0L(%edi),%edi
2206 0x00, 0x00, 0x00, 0x00 };
2207 const char nop13
[13] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2208 0x00, 0x00, 0x8d, 0xbc, // leal 0L(%edi,1),%edi
2209 0x27, 0x00, 0x00, 0x00,
2211 const char nop14
[14] = { 0x8d, 0xb4, 0x26, 0x00, // leal 0L(%esi,1),%esi
2212 0x00, 0x00, 0x00, 0x8d, // leal 0L(%edi,1),%edi
2213 0xbc, 0x27, 0x00, 0x00,
2215 const char nop15
[15] = { 0xeb, 0x0d, 0x90, 0x90, // jmp .+15
2216 0x90, 0x90, 0x90, 0x90, // nop,nop,nop,...
2217 0x90, 0x90, 0x90, 0x90,
2220 const char* nops
[16] = {
2222 nop1
, nop2
, nop3
, nop4
, nop5
, nop6
, nop7
,
2223 nop8
, nop9
, nop10
, nop11
, nop12
, nop13
, nop14
, nop15
2226 return std::string(nops
[length
], length
);
2229 // The selector for i386 object files.
2231 class Target_selector_i386
: public Target_selector
2234 Target_selector_i386()
2235 : Target_selector(elfcpp::EM_386
, 32, false)
2239 recognize(int machine
, int osabi
, int abiversion
);
2242 Target_i386
* target_
;
2245 // Recognize an i386 object file when we already know that the machine
2246 // number is EM_386.
2249 Target_selector_i386::recognize(int, int, int)
2251 if (this->target_
== NULL
)
2252 this->target_
= new Target_i386();
2253 return this->target_
;
2256 Target_selector_i386 target_selector_i386
;
2258 } // End anonymous namespace.