1 // i386.cc -- i386 target support for gold.
3 // Copyright 2006, 2007, 2008, 2009, 2010 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"
48 class Output_data_plt_i386
;
50 // The i386 target class.
51 // TLS info comes from
52 // http://people.redhat.com/drepper/tls.pdf
53 // http://www.lsd.ic.unicamp.br/~oliva/writeups/TLS/RFC-TLSDESC-x86.txt
55 class Target_i386
: public Target_freebsd
<32, false>
58 typedef Output_data_reloc
<elfcpp::SHT_REL
, true, 32, false> Reloc_section
;
61 : Target_freebsd
<32, false>(&i386_info
),
62 got_(NULL
), plt_(NULL
), got_plt_(NULL
), got_tlsdesc_(NULL
),
63 global_offset_table_(NULL
), rel_dyn_(NULL
),
64 copy_relocs_(elfcpp::R_386_COPY
), dynbss_(NULL
),
65 got_mod_index_offset_(-1U), tls_base_symbol_defined_(false)
69 can_check_for_function_pointers() const
72 // Process the relocations to determine unreferenced sections for
73 // garbage collection.
75 gc_process_relocs(Symbol_table
* symtab
,
77 Sized_relobj
<32, false>* object
,
78 unsigned int data_shndx
,
80 const unsigned char* prelocs
,
82 Output_section
* output_section
,
83 bool needs_special_offset_handling
,
84 size_t local_symbol_count
,
85 const unsigned char* plocal_symbols
);
87 // Scan the relocations to look for symbol adjustments.
89 scan_relocs(Symbol_table
* symtab
,
91 Sized_relobj
<32, false>* object
,
92 unsigned int data_shndx
,
94 const unsigned char* prelocs
,
96 Output_section
* output_section
,
97 bool needs_special_offset_handling
,
98 size_t local_symbol_count
,
99 const unsigned char* plocal_symbols
);
101 // Finalize the sections.
103 do_finalize_sections(Layout
*, const Input_objects
*, Symbol_table
*);
105 // Return the value to use for a dynamic which requires special
108 do_dynsym_value(const Symbol
*) const;
110 // Relocate a section.
112 relocate_section(const Relocate_info
<32, false>*,
113 unsigned int sh_type
,
114 const unsigned char* prelocs
,
116 Output_section
* output_section
,
117 bool needs_special_offset_handling
,
119 elfcpp::Elf_types
<32>::Elf_Addr view_address
,
120 section_size_type view_size
,
121 const Reloc_symbol_changes
*);
123 // Scan the relocs during a relocatable link.
125 scan_relocatable_relocs(Symbol_table
* symtab
,
127 Sized_relobj
<32, false>* object
,
128 unsigned int data_shndx
,
129 unsigned int sh_type
,
130 const unsigned char* prelocs
,
132 Output_section
* output_section
,
133 bool needs_special_offset_handling
,
134 size_t local_symbol_count
,
135 const unsigned char* plocal_symbols
,
136 Relocatable_relocs
*);
138 // Relocate a section during a relocatable link.
140 relocate_for_relocatable(const Relocate_info
<32, false>*,
141 unsigned int sh_type
,
142 const unsigned char* prelocs
,
144 Output_section
* output_section
,
145 off_t offset_in_output_section
,
146 const Relocatable_relocs
*,
148 elfcpp::Elf_types
<32>::Elf_Addr view_address
,
149 section_size_type view_size
,
150 unsigned char* reloc_view
,
151 section_size_type reloc_view_size
);
153 // Return a string used to fill a code section with nops.
155 do_code_fill(section_size_type length
) const;
157 // Return whether SYM is defined by the ABI.
159 do_is_defined_by_abi(const Symbol
* sym
) const
160 { return strcmp(sym
->name(), "___tls_get_addr") == 0; }
162 // Return whether a symbol name implies a local label. The UnixWare
163 // 2.1 cc generates temporary symbols that start with .X, so we
164 // recognize them here. FIXME: do other SVR4 compilers also use .X?.
165 // If so, we should move the .X recognition into
166 // Target::do_is_local_label_name.
168 do_is_local_label_name(const char* name
) const
170 if (name
[0] == '.' && name
[1] == 'X')
172 return Target::do_is_local_label_name(name
);
175 // Return whether SYM is call to a non-split function.
177 do_is_call_to_non_split(const Symbol
* sym
, unsigned int) const;
179 // Adjust -fstack-split code which calls non-stack-split code.
181 do_calls_non_split(Relobj
* object
, unsigned int shndx
,
182 section_offset_type fnoffset
, section_size_type fnsize
,
183 unsigned char* view
, section_size_type view_size
,
184 std::string
* from
, std::string
* to
) const;
186 // Return the size of the GOT section.
190 gold_assert(this->got_
!= NULL
);
191 return this->got_
->data_size();
195 // The class which scans relocations.
199 local(Symbol_table
* symtab
, Layout
* layout
, Target_i386
* target
,
200 Sized_relobj
<32, false>* object
,
201 unsigned int data_shndx
,
202 Output_section
* output_section
,
203 const elfcpp::Rel
<32, false>& reloc
, unsigned int r_type
,
204 const elfcpp::Sym
<32, false>& lsym
);
207 global(Symbol_table
* symtab
, Layout
* layout
, Target_i386
* target
,
208 Sized_relobj
<32, false>* object
,
209 unsigned int data_shndx
,
210 Output_section
* output_section
,
211 const elfcpp::Rel
<32, false>& reloc
, unsigned int r_type
,
215 local_reloc_may_be_function_pointer(Symbol_table
* symtab
, Layout
* layout
,
217 Sized_relobj
<32, false>* object
,
218 unsigned int data_shndx
,
219 Output_section
* output_section
,
220 const elfcpp::Rel
<32, false>& reloc
,
222 const elfcpp::Sym
<32, false>& lsym
);
225 global_reloc_may_be_function_pointer(Symbol_table
* symtab
, Layout
* layout
,
227 Sized_relobj
<32, false>* object
,
228 unsigned int data_shndx
,
229 Output_section
* output_section
,
230 const elfcpp::Rel
<32, false>& reloc
,
235 possible_function_pointer_reloc(unsigned int r_type
);
238 unsupported_reloc_local(Sized_relobj
<32, false>*, unsigned int r_type
);
241 unsupported_reloc_global(Sized_relobj
<32, false>*, unsigned int r_type
,
245 // The class which implements relocation.
250 : skip_call_tls_get_addr_(false),
251 local_dynamic_type_(LOCAL_DYNAMIC_NONE
)
256 if (this->skip_call_tls_get_addr_
)
258 // FIXME: This needs to specify the location somehow.
259 gold_error(_("missing expected TLS relocation"));
263 // Return whether the static relocation needs to be applied.
265 should_apply_static_reloc(const Sized_symbol
<32>* gsym
,
268 Output_section
* output_section
);
270 // Do a relocation. Return false if the caller should not issue
271 // any warnings about this relocation.
273 relocate(const Relocate_info
<32, false>*, Target_i386
*, Output_section
*,
274 size_t relnum
, const elfcpp::Rel
<32, false>&,
275 unsigned int r_type
, const Sized_symbol
<32>*,
276 const Symbol_value
<32>*,
277 unsigned char*, elfcpp::Elf_types
<32>::Elf_Addr
,
281 // Do a TLS relocation.
283 relocate_tls(const Relocate_info
<32, false>*, Target_i386
* target
,
284 size_t relnum
, const elfcpp::Rel
<32, false>&,
285 unsigned int r_type
, const Sized_symbol
<32>*,
286 const Symbol_value
<32>*,
287 unsigned char*, elfcpp::Elf_types
<32>::Elf_Addr
,
290 // Do a TLS General-Dynamic to Initial-Exec transition.
292 tls_gd_to_ie(const Relocate_info
<32, false>*, size_t relnum
,
293 Output_segment
* tls_segment
,
294 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
295 elfcpp::Elf_types
<32>::Elf_Addr value
,
297 section_size_type view_size
);
299 // Do a TLS General-Dynamic to Local-Exec transition.
301 tls_gd_to_le(const Relocate_info
<32, false>*, size_t relnum
,
302 Output_segment
* tls_segment
,
303 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
304 elfcpp::Elf_types
<32>::Elf_Addr value
,
306 section_size_type view_size
);
308 // Do a TLS_GOTDESC or TLS_DESC_CALL General-Dynamic to Initial-Exec
311 tls_desc_gd_to_ie(const Relocate_info
<32, false>*, size_t relnum
,
312 Output_segment
* tls_segment
,
313 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
314 elfcpp::Elf_types
<32>::Elf_Addr value
,
316 section_size_type view_size
);
318 // Do a TLS_GOTDESC or TLS_DESC_CALL General-Dynamic to Local-Exec
321 tls_desc_gd_to_le(const Relocate_info
<32, false>*, size_t relnum
,
322 Output_segment
* tls_segment
,
323 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
324 elfcpp::Elf_types
<32>::Elf_Addr value
,
326 section_size_type view_size
);
328 // Do a TLS Local-Dynamic to Local-Exec transition.
330 tls_ld_to_le(const Relocate_info
<32, false>*, size_t relnum
,
331 Output_segment
* tls_segment
,
332 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
333 elfcpp::Elf_types
<32>::Elf_Addr value
,
335 section_size_type view_size
);
337 // Do a TLS Initial-Exec to Local-Exec transition.
339 tls_ie_to_le(const Relocate_info
<32, false>*, size_t relnum
,
340 Output_segment
* tls_segment
,
341 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
342 elfcpp::Elf_types
<32>::Elf_Addr value
,
344 section_size_type view_size
);
346 // We need to keep track of which type of local dynamic relocation
347 // we have seen, so that we can optimize R_386_TLS_LDO_32 correctly.
348 enum Local_dynamic_type
355 // This is set if we should skip the next reloc, which should be a
356 // PLT32 reloc against ___tls_get_addr.
357 bool skip_call_tls_get_addr_
;
358 // The type of local dynamic relocation we have seen in the section
359 // being relocated, if any.
360 Local_dynamic_type local_dynamic_type_
;
363 // A class which returns the size required for a relocation type,
364 // used while scanning relocs during a relocatable link.
365 class Relocatable_size_for_reloc
369 get_size_for_reloc(unsigned int, Relobj
*);
372 // Adjust TLS relocation type based on the options and whether this
373 // is a local symbol.
374 static tls::Tls_optimization
375 optimize_tls_reloc(bool is_final
, int r_type
);
377 // Get the GOT section, creating it if necessary.
378 Output_data_got
<32, false>*
379 got_section(Symbol_table
*, Layout
*);
381 // Get the GOT PLT section.
383 got_plt_section() const
385 gold_assert(this->got_plt_
!= NULL
);
386 return this->got_plt_
;
389 // Get the GOT section for TLSDESC entries.
390 Output_data_got
<32, false>*
391 got_tlsdesc_section() const
393 gold_assert(this->got_tlsdesc_
!= NULL
);
394 return this->got_tlsdesc_
;
397 // Create a PLT entry for a global symbol.
399 make_plt_entry(Symbol_table
*, Layout
*, Symbol
*);
401 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
403 define_tls_base_symbol(Symbol_table
*, Layout
*);
405 // Create a GOT entry for the TLS module index.
407 got_mod_index_entry(Symbol_table
* symtab
, Layout
* layout
,
408 Sized_relobj
<32, false>* object
);
410 // Get the PLT section.
411 Output_data_plt_i386
*
414 gold_assert(this->plt_
!= NULL
);
418 // Get the dynamic reloc section, creating it if necessary.
420 rel_dyn_section(Layout
*);
422 // Get the section to use for TLS_DESC relocations.
424 rel_tls_desc_section(Layout
*) const;
426 // Add a potential copy relocation.
428 copy_reloc(Symbol_table
* symtab
, Layout
* layout
,
429 Sized_relobj
<32, false>* object
,
430 unsigned int shndx
, Output_section
* output_section
,
431 Symbol
* sym
, const elfcpp::Rel
<32, false>& reloc
)
433 this->copy_relocs_
.copy_reloc(symtab
, layout
,
434 symtab
->get_sized_symbol
<32>(sym
),
435 object
, shndx
, output_section
, reloc
,
436 this->rel_dyn_section(layout
));
439 // Information about this specific target which we pass to the
440 // general Target structure.
441 static const Target::Target_info i386_info
;
443 // The types of GOT entries needed for this platform.
446 GOT_TYPE_STANDARD
= 0, // GOT entry for a regular symbol
447 GOT_TYPE_TLS_NOFFSET
= 1, // GOT entry for negative TLS offset
448 GOT_TYPE_TLS_OFFSET
= 2, // GOT entry for positive TLS offset
449 GOT_TYPE_TLS_PAIR
= 3, // GOT entry for TLS module/offset pair
450 GOT_TYPE_TLS_DESC
= 4 // GOT entry for TLS_DESC pair
454 Output_data_got
<32, false>* got_
;
456 Output_data_plt_i386
* plt_
;
457 // The GOT PLT section.
458 Output_data_space
* got_plt_
;
459 // The GOT section for TLSDESC relocations.
460 Output_data_got
<32, false>* got_tlsdesc_
;
461 // The _GLOBAL_OFFSET_TABLE_ symbol.
462 Symbol
* global_offset_table_
;
463 // The dynamic reloc section.
464 Reloc_section
* rel_dyn_
;
465 // Relocs saved to avoid a COPY reloc.
466 Copy_relocs
<elfcpp::SHT_REL
, 32, false> copy_relocs_
;
467 // Space for variables copied with a COPY reloc.
468 Output_data_space
* dynbss_
;
469 // Offset of the GOT entry for the TLS module index.
470 unsigned int got_mod_index_offset_
;
471 // True if the _TLS_MODULE_BASE_ symbol has been defined.
472 bool tls_base_symbol_defined_
;
475 const Target::Target_info
Target_i386::i386_info
=
478 false, // is_big_endian
479 elfcpp::EM_386
, // machine_code
480 false, // has_make_symbol
481 false, // has_resolve
482 true, // has_code_fill
483 true, // is_default_stack_executable
485 "/usr/lib/libc.so.1", // dynamic_linker
486 0x08048000, // default_text_segment_address
487 0x1000, // abi_pagesize (overridable by -z max-page-size)
488 0x1000, // common_pagesize (overridable by -z common-page-size)
489 elfcpp::SHN_UNDEF
, // small_common_shndx
490 elfcpp::SHN_UNDEF
, // large_common_shndx
491 0, // small_common_section_flags
492 0, // large_common_section_flags
493 NULL
, // attributes_section
494 NULL
// attributes_vendor
497 // Get the GOT section, creating it if necessary.
499 Output_data_got
<32, false>*
500 Target_i386::got_section(Symbol_table
* symtab
, Layout
* layout
)
502 if (this->got_
== NULL
)
504 gold_assert(symtab
!= NULL
&& layout
!= NULL
);
506 this->got_
= new Output_data_got
<32, false>();
508 layout
->add_output_section_data(".got", elfcpp::SHT_PROGBITS
,
510 | elfcpp::SHF_WRITE
),
511 this->got_
, ORDER_RELRO_LAST
, true);
513 this->got_plt_
= new Output_data_space(4, "** GOT PLT");
514 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
516 | elfcpp::SHF_WRITE
),
517 this->got_plt_
, ORDER_NON_RELRO_FIRST
,
520 // The first three entries are reserved.
521 this->got_plt_
->set_current_data_size(3 * 4);
523 // Those bytes can go into the relro segment.
524 layout
->increase_relro(3 * 4);
526 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
527 this->global_offset_table_
=
528 symtab
->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL
,
529 Symbol_table::PREDEFINED
,
531 0, 0, elfcpp::STT_OBJECT
,
533 elfcpp::STV_HIDDEN
, 0,
536 // If there are any TLSDESC relocations, they get GOT entries in
537 // .got.plt after the jump slot entries.
538 this->got_tlsdesc_
= new Output_data_got
<32, false>();
539 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
541 | elfcpp::SHF_WRITE
),
543 ORDER_NON_RELRO_FIRST
, false);
549 // Get the dynamic reloc section, creating it if necessary.
551 Target_i386::Reloc_section
*
552 Target_i386::rel_dyn_section(Layout
* layout
)
554 if (this->rel_dyn_
== NULL
)
556 gold_assert(layout
!= NULL
);
557 this->rel_dyn_
= new Reloc_section(parameters
->options().combreloc());
558 layout
->add_output_section_data(".rel.dyn", elfcpp::SHT_REL
,
559 elfcpp::SHF_ALLOC
, this->rel_dyn_
,
560 ORDER_DYNAMIC_RELOCS
, false);
562 return this->rel_dyn_
;
565 // A class to handle the PLT data.
567 class Output_data_plt_i386
: public Output_section_data
570 typedef Output_data_reloc
<elfcpp::SHT_REL
, true, 32, false> Reloc_section
;
572 Output_data_plt_i386(Layout
*, Output_data_space
*);
574 // Add an entry to the PLT.
576 add_entry(Symbol
* gsym
);
578 // Return the .rel.plt section data.
581 { return this->rel_
; }
583 // Return where the TLS_DESC relocations should go.
585 rel_tls_desc(Layout
*);
589 do_adjust_output_section(Output_section
* os
);
591 // Write to a map file.
593 do_print_to_mapfile(Mapfile
* mapfile
) const
594 { mapfile
->print_output_data(this, _("** PLT")); }
597 // The size of an entry in the PLT.
598 static const int plt_entry_size
= 16;
600 // The first entry in the PLT for an executable.
601 static unsigned char exec_first_plt_entry
[plt_entry_size
];
603 // The first entry in the PLT for a shared object.
604 static unsigned char dyn_first_plt_entry
[plt_entry_size
];
606 // Other entries in the PLT for an executable.
607 static unsigned char exec_plt_entry
[plt_entry_size
];
609 // Other entries in the PLT for a shared object.
610 static unsigned char dyn_plt_entry
[plt_entry_size
];
612 // Set the final size.
614 set_final_data_size()
615 { this->set_data_size((this->count_
+ 1) * plt_entry_size
); }
617 // Write out the PLT data.
619 do_write(Output_file
*);
621 // The reloc section.
623 // The TLS_DESC relocations, if necessary. These must follow the
624 // regular PLT relocs.
625 Reloc_section
* tls_desc_rel_
;
626 // The .got.plt section.
627 Output_data_space
* got_plt_
;
628 // The number of PLT entries.
632 // Create the PLT section. The ordinary .got section is an argument,
633 // since we need to refer to the start. We also create our own .got
634 // section just for PLT entries.
636 Output_data_plt_i386::Output_data_plt_i386(Layout
* layout
,
637 Output_data_space
* got_plt
)
638 : Output_section_data(4), tls_desc_rel_(NULL
), got_plt_(got_plt
), count_(0)
640 this->rel_
= new Reloc_section(false);
641 layout
->add_output_section_data(".rel.plt", elfcpp::SHT_REL
,
642 elfcpp::SHF_ALLOC
, this->rel_
,
643 ORDER_DYNAMIC_PLT_RELOCS
, false);
647 Output_data_plt_i386::do_adjust_output_section(Output_section
* os
)
649 // UnixWare sets the entsize of .plt to 4, and so does the old GNU
650 // linker, and so do we.
654 // Add an entry to the PLT.
657 Output_data_plt_i386::add_entry(Symbol
* gsym
)
659 gold_assert(!gsym
->has_plt_offset());
661 // Note that when setting the PLT offset we skip the initial
662 // reserved PLT entry.
663 gsym
->set_plt_offset((this->count_
+ 1) * plt_entry_size
);
667 section_offset_type got_offset
= this->got_plt_
->current_data_size();
669 // Every PLT entry needs a GOT entry which points back to the PLT
670 // entry (this will be changed by the dynamic linker, normally
671 // lazily when the function is called).
672 this->got_plt_
->set_current_data_size(got_offset
+ 4);
674 // Every PLT entry needs a reloc.
675 gsym
->set_needs_dynsym_entry();
676 this->rel_
->add_global(gsym
, elfcpp::R_386_JUMP_SLOT
, this->got_plt_
,
679 // Note that we don't need to save the symbol. The contents of the
680 // PLT are independent of which symbols are used. The symbols only
681 // appear in the relocations.
684 // Return where the TLS_DESC relocations should go, creating it if
685 // necessary. These follow the JUMP_SLOT relocations.
687 Output_data_plt_i386::Reloc_section
*
688 Output_data_plt_i386::rel_tls_desc(Layout
* layout
)
690 if (this->tls_desc_rel_
== NULL
)
692 this->tls_desc_rel_
= new Reloc_section(false);
693 layout
->add_output_section_data(".rel.plt", elfcpp::SHT_REL
,
694 elfcpp::SHF_ALLOC
, this->tls_desc_rel_
,
695 ORDER_DYNAMIC_PLT_RELOCS
, false);
696 gold_assert(this->tls_desc_rel_
->output_section() ==
697 this->rel_
->output_section());
699 return this->tls_desc_rel_
;
702 // The first entry in the PLT for an executable.
704 unsigned char Output_data_plt_i386::exec_first_plt_entry
[plt_entry_size
] =
706 0xff, 0x35, // pushl contents of memory address
707 0, 0, 0, 0, // replaced with address of .got + 4
708 0xff, 0x25, // jmp indirect
709 0, 0, 0, 0, // replaced with address of .got + 8
713 // The first entry in the PLT for a shared object.
715 unsigned char Output_data_plt_i386::dyn_first_plt_entry
[plt_entry_size
] =
717 0xff, 0xb3, 4, 0, 0, 0, // pushl 4(%ebx)
718 0xff, 0xa3, 8, 0, 0, 0, // jmp *8(%ebx)
722 // Subsequent entries in the PLT for an executable.
724 unsigned char Output_data_plt_i386::exec_plt_entry
[plt_entry_size
] =
726 0xff, 0x25, // jmp indirect
727 0, 0, 0, 0, // replaced with address of symbol in .got
728 0x68, // pushl immediate
729 0, 0, 0, 0, // replaced with offset into relocation table
730 0xe9, // jmp relative
731 0, 0, 0, 0 // replaced with offset to start of .plt
734 // Subsequent entries in the PLT for a shared object.
736 unsigned char Output_data_plt_i386::dyn_plt_entry
[plt_entry_size
] =
738 0xff, 0xa3, // jmp *offset(%ebx)
739 0, 0, 0, 0, // replaced with offset of symbol in .got
740 0x68, // pushl immediate
741 0, 0, 0, 0, // replaced with offset into relocation table
742 0xe9, // jmp relative
743 0, 0, 0, 0 // replaced with offset to start of .plt
746 // Write out the PLT. This uses the hand-coded instructions above,
747 // and adjusts them as needed. This is all specified by the i386 ELF
748 // Processor Supplement.
751 Output_data_plt_i386::do_write(Output_file
* of
)
753 const off_t offset
= this->offset();
754 const section_size_type oview_size
=
755 convert_to_section_size_type(this->data_size());
756 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
758 const off_t got_file_offset
= this->got_plt_
->offset();
759 const section_size_type got_size
=
760 convert_to_section_size_type(this->got_plt_
->data_size());
761 unsigned char* const got_view
= of
->get_output_view(got_file_offset
,
764 unsigned char* pov
= oview
;
766 elfcpp::Elf_types
<32>::Elf_Addr plt_address
= this->address();
767 elfcpp::Elf_types
<32>::Elf_Addr got_address
= this->got_plt_
->address();
769 if (parameters
->options().output_is_position_independent())
770 memcpy(pov
, dyn_first_plt_entry
, plt_entry_size
);
773 memcpy(pov
, exec_first_plt_entry
, plt_entry_size
);
774 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2, got_address
+ 4);
775 elfcpp::Swap
<32, false>::writeval(pov
+ 8, got_address
+ 8);
777 pov
+= plt_entry_size
;
779 unsigned char* got_pov
= got_view
;
781 memset(got_pov
, 0, 12);
784 const int rel_size
= elfcpp::Elf_sizes
<32>::rel_size
;
786 unsigned int plt_offset
= plt_entry_size
;
787 unsigned int plt_rel_offset
= 0;
788 unsigned int got_offset
= 12;
789 const unsigned int count
= this->count_
;
790 for (unsigned int i
= 0;
793 pov
+= plt_entry_size
,
795 plt_offset
+= plt_entry_size
,
796 plt_rel_offset
+= rel_size
,
799 // Set and adjust the PLT entry itself.
801 if (parameters
->options().output_is_position_independent())
803 memcpy(pov
, dyn_plt_entry
, plt_entry_size
);
804 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2, got_offset
);
808 memcpy(pov
, exec_plt_entry
, plt_entry_size
);
809 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
814 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 7, plt_rel_offset
);
815 elfcpp::Swap
<32, false>::writeval(pov
+ 12,
816 - (plt_offset
+ plt_entry_size
));
818 // Set the entry in the GOT.
819 elfcpp::Swap
<32, false>::writeval(got_pov
, plt_address
+ plt_offset
+ 6);
822 gold_assert(static_cast<section_size_type
>(pov
- oview
) == oview_size
);
823 gold_assert(static_cast<section_size_type
>(got_pov
- got_view
) == got_size
);
825 of
->write_output_view(offset
, oview_size
, oview
);
826 of
->write_output_view(got_file_offset
, got_size
, got_view
);
829 // Create a PLT entry for a global symbol.
832 Target_i386::make_plt_entry(Symbol_table
* symtab
, Layout
* layout
, Symbol
* gsym
)
834 if (gsym
->has_plt_offset())
837 if (this->plt_
== NULL
)
839 // Create the GOT sections first.
840 this->got_section(symtab
, layout
);
842 this->plt_
= new Output_data_plt_i386(layout
, this->got_plt_
);
843 layout
->add_output_section_data(".plt", elfcpp::SHT_PROGBITS
,
845 | elfcpp::SHF_EXECINSTR
),
846 this->plt_
, ORDER_PLT
, false);
849 this->plt_
->add_entry(gsym
);
852 // Get the section to use for TLS_DESC relocations.
854 Target_i386::Reloc_section
*
855 Target_i386::rel_tls_desc_section(Layout
* layout
) const
857 return this->plt_section()->rel_tls_desc(layout
);
860 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
863 Target_i386::define_tls_base_symbol(Symbol_table
* symtab
, Layout
* layout
)
865 if (this->tls_base_symbol_defined_
)
868 Output_segment
* tls_segment
= layout
->tls_segment();
869 if (tls_segment
!= NULL
)
871 bool is_exec
= parameters
->options().output_is_executable();
872 symtab
->define_in_output_segment("_TLS_MODULE_BASE_", NULL
,
873 Symbol_table::PREDEFINED
,
877 elfcpp::STV_HIDDEN
, 0,
879 ? Symbol::SEGMENT_END
880 : Symbol::SEGMENT_START
),
883 this->tls_base_symbol_defined_
= true;
886 // Create a GOT entry for the TLS module index.
889 Target_i386::got_mod_index_entry(Symbol_table
* symtab
, Layout
* layout
,
890 Sized_relobj
<32, false>* object
)
892 if (this->got_mod_index_offset_
== -1U)
894 gold_assert(symtab
!= NULL
&& layout
!= NULL
&& object
!= NULL
);
895 Reloc_section
* rel_dyn
= this->rel_dyn_section(layout
);
896 Output_data_got
<32, false>* got
= this->got_section(symtab
, layout
);
897 unsigned int got_offset
= got
->add_constant(0);
898 rel_dyn
->add_local(object
, 0, elfcpp::R_386_TLS_DTPMOD32
, got
,
900 got
->add_constant(0);
901 this->got_mod_index_offset_
= got_offset
;
903 return this->got_mod_index_offset_
;
906 // Optimize the TLS relocation type based on what we know about the
907 // symbol. IS_FINAL is true if the final address of this symbol is
908 // known at link time.
910 tls::Tls_optimization
911 Target_i386::optimize_tls_reloc(bool is_final
, int r_type
)
913 // If we are generating a shared library, then we can't do anything
915 if (parameters
->options().shared())
916 return tls::TLSOPT_NONE
;
920 case elfcpp::R_386_TLS_GD
:
921 case elfcpp::R_386_TLS_GOTDESC
:
922 case elfcpp::R_386_TLS_DESC_CALL
:
923 // These are General-Dynamic which permits fully general TLS
924 // access. Since we know that we are generating an executable,
925 // we can convert this to Initial-Exec. If we also know that
926 // this is a local symbol, we can further switch to Local-Exec.
928 return tls::TLSOPT_TO_LE
;
929 return tls::TLSOPT_TO_IE
;
931 case elfcpp::R_386_TLS_LDM
:
932 // This is Local-Dynamic, which refers to a local symbol in the
933 // dynamic TLS block. Since we know that we generating an
934 // executable, we can switch to Local-Exec.
935 return tls::TLSOPT_TO_LE
;
937 case elfcpp::R_386_TLS_LDO_32
:
938 // Another type of Local-Dynamic relocation.
939 return tls::TLSOPT_TO_LE
;
941 case elfcpp::R_386_TLS_IE
:
942 case elfcpp::R_386_TLS_GOTIE
:
943 case elfcpp::R_386_TLS_IE_32
:
944 // These are Initial-Exec relocs which get the thread offset
945 // from the GOT. If we know that we are linking against the
946 // local symbol, we can switch to Local-Exec, which links the
947 // thread offset into the instruction.
949 return tls::TLSOPT_TO_LE
;
950 return tls::TLSOPT_NONE
;
952 case elfcpp::R_386_TLS_LE
:
953 case elfcpp::R_386_TLS_LE_32
:
954 // When we already have Local-Exec, there is nothing further we
956 return tls::TLSOPT_NONE
;
963 // Report an unsupported relocation against a local symbol.
966 Target_i386::Scan::unsupported_reloc_local(Sized_relobj
<32, false>* object
,
969 gold_error(_("%s: unsupported reloc %u against local symbol"),
970 object
->name().c_str(), r_type
);
973 // Scan a relocation for a local symbol.
976 Target_i386::Scan::local(Symbol_table
* symtab
,
979 Sized_relobj
<32, false>* object
,
980 unsigned int data_shndx
,
981 Output_section
* output_section
,
982 const elfcpp::Rel
<32, false>& reloc
,
984 const elfcpp::Sym
<32, false>& lsym
)
988 case elfcpp::R_386_NONE
:
989 case elfcpp::R_386_GNU_VTINHERIT
:
990 case elfcpp::R_386_GNU_VTENTRY
:
993 case elfcpp::R_386_32
:
994 // If building a shared library (or a position-independent
995 // executable), we need to create a dynamic relocation for
996 // this location. The relocation applied at link time will
997 // apply the link-time value, so we flag the location with
998 // an R_386_RELATIVE relocation so the dynamic loader can
999 // relocate it easily.
1000 if (parameters
->options().output_is_position_independent())
1002 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1003 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1004 rel_dyn
->add_local_relative(object
, r_sym
, elfcpp::R_386_RELATIVE
,
1005 output_section
, data_shndx
,
1006 reloc
.get_r_offset());
1010 case elfcpp::R_386_16
:
1011 case elfcpp::R_386_8
:
1012 // If building a shared library (or a position-independent
1013 // executable), we need to create a dynamic relocation for
1014 // this location. Because the addend needs to remain in the
1015 // data section, we need to be careful not to apply this
1016 // relocation statically.
1017 if (parameters
->options().output_is_position_independent())
1019 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1020 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1021 if (lsym
.get_st_type() != elfcpp::STT_SECTION
)
1022 rel_dyn
->add_local(object
, r_sym
, r_type
, output_section
,
1023 data_shndx
, reloc
.get_r_offset());
1026 gold_assert(lsym
.get_st_value() == 0);
1027 unsigned int shndx
= lsym
.get_st_shndx();
1029 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
,
1032 object
->error(_("section symbol %u has bad shndx %u"),
1035 rel_dyn
->add_local_section(object
, shndx
,
1036 r_type
, output_section
,
1037 data_shndx
, reloc
.get_r_offset());
1042 case elfcpp::R_386_PC32
:
1043 case elfcpp::R_386_PC16
:
1044 case elfcpp::R_386_PC8
:
1047 case elfcpp::R_386_PLT32
:
1048 // Since we know this is a local symbol, we can handle this as a
1052 case elfcpp::R_386_GOTOFF
:
1053 case elfcpp::R_386_GOTPC
:
1054 // We need a GOT section.
1055 target
->got_section(symtab
, layout
);
1058 case elfcpp::R_386_GOT32
:
1060 // The symbol requires a GOT entry.
1061 Output_data_got
<32, false>* got
= target
->got_section(symtab
, layout
);
1062 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1063 if (got
->add_local(object
, r_sym
, GOT_TYPE_STANDARD
))
1065 // If we are generating a shared object, we need to add a
1066 // dynamic RELATIVE relocation for this symbol's GOT entry.
1067 if (parameters
->options().output_is_position_independent())
1069 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1070 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1071 rel_dyn
->add_local_relative(
1072 object
, r_sym
, elfcpp::R_386_RELATIVE
, got
,
1073 object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
));
1079 // These are relocations which should only be seen by the
1080 // dynamic linker, and should never be seen here.
1081 case elfcpp::R_386_COPY
:
1082 case elfcpp::R_386_GLOB_DAT
:
1083 case elfcpp::R_386_JUMP_SLOT
:
1084 case elfcpp::R_386_RELATIVE
:
1085 case elfcpp::R_386_TLS_TPOFF
:
1086 case elfcpp::R_386_TLS_DTPMOD32
:
1087 case elfcpp::R_386_TLS_DTPOFF32
:
1088 case elfcpp::R_386_TLS_TPOFF32
:
1089 case elfcpp::R_386_TLS_DESC
:
1090 gold_error(_("%s: unexpected reloc %u in object file"),
1091 object
->name().c_str(), r_type
);
1094 // These are initial TLS relocs, which are expected when
1096 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1097 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
1098 case elfcpp::R_386_TLS_DESC_CALL
:
1099 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1100 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1101 case elfcpp::R_386_TLS_IE
: // Initial-exec
1102 case elfcpp::R_386_TLS_IE_32
:
1103 case elfcpp::R_386_TLS_GOTIE
:
1104 case elfcpp::R_386_TLS_LE
: // Local-exec
1105 case elfcpp::R_386_TLS_LE_32
:
1107 bool output_is_shared
= parameters
->options().shared();
1108 const tls::Tls_optimization optimized_type
1109 = Target_i386::optimize_tls_reloc(!output_is_shared
, r_type
);
1112 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1113 if (optimized_type
== tls::TLSOPT_NONE
)
1115 // Create a pair of GOT entries for the module index and
1116 // dtv-relative offset.
1117 Output_data_got
<32, false>* got
1118 = target
->got_section(symtab
, layout
);
1119 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1120 unsigned int shndx
= lsym
.get_st_shndx();
1122 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
, &is_ordinary
);
1124 object
->error(_("local symbol %u has bad shndx %u"),
1127 got
->add_local_pair_with_rel(object
, r_sym
, shndx
,
1129 target
->rel_dyn_section(layout
),
1130 elfcpp::R_386_TLS_DTPMOD32
, 0);
1132 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1133 unsupported_reloc_local(object
, r_type
);
1136 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva)
1137 target
->define_tls_base_symbol(symtab
, layout
);
1138 if (optimized_type
== tls::TLSOPT_NONE
)
1140 // Create a double GOT entry with an R_386_TLS_DESC
1141 // reloc. The R_386_TLS_DESC reloc is resolved
1142 // lazily, so the GOT entry needs to be in an area in
1143 // .got.plt, not .got. Call got_section to make sure
1144 // the section has been created.
1145 target
->got_section(symtab
, layout
);
1146 Output_data_got
<32, false>* got
= target
->got_tlsdesc_section();
1147 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1148 if (!object
->local_has_got_offset(r_sym
, GOT_TYPE_TLS_DESC
))
1150 unsigned int got_offset
= got
->add_constant(0);
1151 // The local symbol value is stored in the second
1153 got
->add_local(object
, r_sym
, GOT_TYPE_TLS_DESC
);
1154 // That set the GOT offset of the local symbol to
1155 // point to the second entry, but we want it to
1156 // point to the first.
1157 object
->set_local_got_offset(r_sym
, GOT_TYPE_TLS_DESC
,
1159 Reloc_section
* rt
= target
->rel_tls_desc_section(layout
);
1160 rt
->add_absolute(elfcpp::R_386_TLS_DESC
, got
, got_offset
);
1163 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1164 unsupported_reloc_local(object
, r_type
);
1167 case elfcpp::R_386_TLS_DESC_CALL
:
1170 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1171 if (optimized_type
== tls::TLSOPT_NONE
)
1173 // Create a GOT entry for the module index.
1174 target
->got_mod_index_entry(symtab
, layout
, object
);
1176 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1177 unsupported_reloc_local(object
, r_type
);
1180 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1183 case elfcpp::R_386_TLS_IE
: // Initial-exec
1184 case elfcpp::R_386_TLS_IE_32
:
1185 case elfcpp::R_386_TLS_GOTIE
:
1186 layout
->set_has_static_tls();
1187 if (optimized_type
== tls::TLSOPT_NONE
)
1189 // For the R_386_TLS_IE relocation, we need to create a
1190 // dynamic relocation when building a shared library.
1191 if (r_type
== elfcpp::R_386_TLS_IE
1192 && parameters
->options().shared())
1194 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1196 = elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1197 rel_dyn
->add_local_relative(object
, r_sym
,
1198 elfcpp::R_386_RELATIVE
,
1199 output_section
, data_shndx
,
1200 reloc
.get_r_offset());
1202 // Create a GOT entry for the tp-relative offset.
1203 Output_data_got
<32, false>* got
1204 = target
->got_section(symtab
, layout
);
1205 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1206 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_IE_32
1207 ? elfcpp::R_386_TLS_TPOFF32
1208 : elfcpp::R_386_TLS_TPOFF
);
1209 unsigned int got_type
= (r_type
== elfcpp::R_386_TLS_IE_32
1210 ? GOT_TYPE_TLS_OFFSET
1211 : GOT_TYPE_TLS_NOFFSET
);
1212 got
->add_local_with_rel(object
, r_sym
, got_type
,
1213 target
->rel_dyn_section(layout
),
1216 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1217 unsupported_reloc_local(object
, r_type
);
1220 case elfcpp::R_386_TLS_LE
: // Local-exec
1221 case elfcpp::R_386_TLS_LE_32
:
1222 layout
->set_has_static_tls();
1223 if (output_is_shared
)
1225 // We need to create a dynamic relocation.
1226 gold_assert(lsym
.get_st_type() != elfcpp::STT_SECTION
);
1227 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1228 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_LE_32
1229 ? elfcpp::R_386_TLS_TPOFF32
1230 : elfcpp::R_386_TLS_TPOFF
);
1231 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1232 rel_dyn
->add_local(object
, r_sym
, dyn_r_type
, output_section
,
1233 data_shndx
, reloc
.get_r_offset());
1243 case elfcpp::R_386_32PLT
:
1244 case elfcpp::R_386_TLS_GD_32
:
1245 case elfcpp::R_386_TLS_GD_PUSH
:
1246 case elfcpp::R_386_TLS_GD_CALL
:
1247 case elfcpp::R_386_TLS_GD_POP
:
1248 case elfcpp::R_386_TLS_LDM_32
:
1249 case elfcpp::R_386_TLS_LDM_PUSH
:
1250 case elfcpp::R_386_TLS_LDM_CALL
:
1251 case elfcpp::R_386_TLS_LDM_POP
:
1252 case elfcpp::R_386_USED_BY_INTEL_200
:
1254 unsupported_reloc_local(object
, r_type
);
1259 // Report an unsupported relocation against a global symbol.
1262 Target_i386::Scan::unsupported_reloc_global(Sized_relobj
<32, false>* object
,
1263 unsigned int r_type
,
1266 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
1267 object
->name().c_str(), r_type
, gsym
->demangled_name().c_str());
1271 Target_i386::Scan::possible_function_pointer_reloc(unsigned int r_type
)
1275 case elfcpp::R_386_32
:
1276 case elfcpp::R_386_16
:
1277 case elfcpp::R_386_8
:
1278 case elfcpp::R_386_GOTOFF
:
1279 case elfcpp::R_386_GOT32
:
1290 Target_i386::Scan::local_reloc_may_be_function_pointer(
1294 Sized_relobj
<32, false>* ,
1297 const elfcpp::Rel
<32, false>& ,
1298 unsigned int r_type
,
1299 const elfcpp::Sym
<32, false>&)
1301 return possible_function_pointer_reloc(r_type
);
1305 Target_i386::Scan::global_reloc_may_be_function_pointer(
1309 Sized_relobj
<32, false>* ,
1312 const elfcpp::Rel
<32, false>& ,
1313 unsigned int r_type
,
1316 return possible_function_pointer_reloc(r_type
);
1319 // Scan a relocation for a global symbol.
1322 Target_i386::Scan::global(Symbol_table
* symtab
,
1324 Target_i386
* target
,
1325 Sized_relobj
<32, false>* object
,
1326 unsigned int data_shndx
,
1327 Output_section
* output_section
,
1328 const elfcpp::Rel
<32, false>& reloc
,
1329 unsigned int r_type
,
1334 case elfcpp::R_386_NONE
:
1335 case elfcpp::R_386_GNU_VTINHERIT
:
1336 case elfcpp::R_386_GNU_VTENTRY
:
1339 case elfcpp::R_386_32
:
1340 case elfcpp::R_386_16
:
1341 case elfcpp::R_386_8
:
1343 // Make a PLT entry if necessary.
1344 if (gsym
->needs_plt_entry())
1346 target
->make_plt_entry(symtab
, layout
, gsym
);
1347 // Since this is not a PC-relative relocation, we may be
1348 // taking the address of a function. In that case we need to
1349 // set the entry in the dynamic symbol table to the address of
1351 if (gsym
->is_from_dynobj() && !parameters
->options().shared())
1352 gsym
->set_needs_dynsym_value();
1354 // Make a dynamic relocation if necessary.
1355 if (gsym
->needs_dynamic_reloc(Symbol::ABSOLUTE_REF
))
1357 if (gsym
->may_need_copy_reloc())
1359 target
->copy_reloc(symtab
, layout
, object
,
1360 data_shndx
, output_section
, gsym
, reloc
);
1362 else if (r_type
== elfcpp::R_386_32
1363 && gsym
->can_use_relative_reloc(false))
1365 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1366 rel_dyn
->add_global_relative(gsym
, elfcpp::R_386_RELATIVE
,
1367 output_section
, object
,
1368 data_shndx
, reloc
.get_r_offset());
1372 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1373 rel_dyn
->add_global(gsym
, r_type
, output_section
, object
,
1374 data_shndx
, reloc
.get_r_offset());
1380 case elfcpp::R_386_PC32
:
1381 case elfcpp::R_386_PC16
:
1382 case elfcpp::R_386_PC8
:
1384 // Make a PLT entry if necessary.
1385 if (gsym
->needs_plt_entry())
1387 // These relocations are used for function calls only in
1388 // non-PIC code. For a 32-bit relocation in a shared library,
1389 // we'll need a text relocation anyway, so we can skip the
1390 // PLT entry and let the dynamic linker bind the call directly
1391 // to the target. For smaller relocations, we should use a
1392 // PLT entry to ensure that the call can reach.
1393 if (!parameters
->options().shared()
1394 || r_type
!= elfcpp::R_386_PC32
)
1395 target
->make_plt_entry(symtab
, layout
, gsym
);
1397 // Make a dynamic relocation if necessary.
1398 int flags
= Symbol::NON_PIC_REF
;
1399 if (gsym
->is_func())
1400 flags
|= Symbol::FUNCTION_CALL
;
1401 if (gsym
->needs_dynamic_reloc(flags
))
1403 if (gsym
->may_need_copy_reloc())
1405 target
->copy_reloc(symtab
, layout
, object
,
1406 data_shndx
, output_section
, gsym
, reloc
);
1410 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1411 rel_dyn
->add_global(gsym
, r_type
, output_section
, object
,
1412 data_shndx
, reloc
.get_r_offset());
1418 case elfcpp::R_386_GOT32
:
1420 // The symbol requires a GOT entry.
1421 Output_data_got
<32, false>* got
= target
->got_section(symtab
, layout
);
1422 if (gsym
->final_value_is_known())
1423 got
->add_global(gsym
, GOT_TYPE_STANDARD
);
1426 // If this symbol is not fully resolved, we need to add a
1427 // GOT entry with a dynamic relocation.
1428 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1429 if (gsym
->is_from_dynobj()
1430 || gsym
->is_undefined()
1431 || gsym
->is_preemptible())
1432 got
->add_global_with_rel(gsym
, GOT_TYPE_STANDARD
,
1433 rel_dyn
, elfcpp::R_386_GLOB_DAT
);
1436 if (got
->add_global(gsym
, GOT_TYPE_STANDARD
))
1437 rel_dyn
->add_global_relative(
1438 gsym
, elfcpp::R_386_RELATIVE
, got
,
1439 gsym
->got_offset(GOT_TYPE_STANDARD
));
1445 case elfcpp::R_386_PLT32
:
1446 // If the symbol is fully resolved, this is just a PC32 reloc.
1447 // Otherwise we need a PLT entry.
1448 if (gsym
->final_value_is_known())
1450 // If building a shared library, we can also skip the PLT entry
1451 // if the symbol is defined in the output file and is protected
1453 if (gsym
->is_defined()
1454 && !gsym
->is_from_dynobj()
1455 && !gsym
->is_preemptible())
1457 target
->make_plt_entry(symtab
, layout
, gsym
);
1460 case elfcpp::R_386_GOTOFF
:
1461 case elfcpp::R_386_GOTPC
:
1462 // We need a GOT section.
1463 target
->got_section(symtab
, layout
);
1466 // These are relocations which should only be seen by the
1467 // dynamic linker, and should never be seen here.
1468 case elfcpp::R_386_COPY
:
1469 case elfcpp::R_386_GLOB_DAT
:
1470 case elfcpp::R_386_JUMP_SLOT
:
1471 case elfcpp::R_386_RELATIVE
:
1472 case elfcpp::R_386_TLS_TPOFF
:
1473 case elfcpp::R_386_TLS_DTPMOD32
:
1474 case elfcpp::R_386_TLS_DTPOFF32
:
1475 case elfcpp::R_386_TLS_TPOFF32
:
1476 case elfcpp::R_386_TLS_DESC
:
1477 gold_error(_("%s: unexpected reloc %u in object file"),
1478 object
->name().c_str(), r_type
);
1481 // These are initial tls relocs, which are expected when
1483 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1484 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
1485 case elfcpp::R_386_TLS_DESC_CALL
:
1486 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1487 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1488 case elfcpp::R_386_TLS_IE
: // Initial-exec
1489 case elfcpp::R_386_TLS_IE_32
:
1490 case elfcpp::R_386_TLS_GOTIE
:
1491 case elfcpp::R_386_TLS_LE
: // Local-exec
1492 case elfcpp::R_386_TLS_LE_32
:
1494 const bool is_final
= gsym
->final_value_is_known();
1495 const tls::Tls_optimization optimized_type
1496 = Target_i386::optimize_tls_reloc(is_final
, r_type
);
1499 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1500 if (optimized_type
== tls::TLSOPT_NONE
)
1502 // Create a pair of GOT entries for the module index and
1503 // dtv-relative offset.
1504 Output_data_got
<32, false>* got
1505 = target
->got_section(symtab
, layout
);
1506 got
->add_global_pair_with_rel(gsym
, GOT_TYPE_TLS_PAIR
,
1507 target
->rel_dyn_section(layout
),
1508 elfcpp::R_386_TLS_DTPMOD32
,
1509 elfcpp::R_386_TLS_DTPOFF32
);
1511 else if (optimized_type
== tls::TLSOPT_TO_IE
)
1513 // Create a GOT entry for the tp-relative offset.
1514 Output_data_got
<32, false>* got
1515 = target
->got_section(symtab
, layout
);
1516 got
->add_global_with_rel(gsym
, GOT_TYPE_TLS_NOFFSET
,
1517 target
->rel_dyn_section(layout
),
1518 elfcpp::R_386_TLS_TPOFF
);
1520 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1521 unsupported_reloc_global(object
, r_type
, gsym
);
1524 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (~oliva url)
1525 target
->define_tls_base_symbol(symtab
, layout
);
1526 if (optimized_type
== tls::TLSOPT_NONE
)
1528 // Create a double GOT entry with an R_386_TLS_DESC
1529 // reloc. The R_386_TLS_DESC reloc is resolved
1530 // lazily, so the GOT entry needs to be in an area in
1531 // .got.plt, not .got. Call got_section to make sure
1532 // the section has been created.
1533 target
->got_section(symtab
, layout
);
1534 Output_data_got
<32, false>* got
= target
->got_tlsdesc_section();
1535 Reloc_section
* rt
= target
->rel_tls_desc_section(layout
);
1536 got
->add_global_pair_with_rel(gsym
, GOT_TYPE_TLS_DESC
, rt
,
1537 elfcpp::R_386_TLS_DESC
, 0);
1539 else if (optimized_type
== tls::TLSOPT_TO_IE
)
1541 // Create a GOT entry for the tp-relative offset.
1542 Output_data_got
<32, false>* got
1543 = target
->got_section(symtab
, layout
);
1544 got
->add_global_with_rel(gsym
, GOT_TYPE_TLS_NOFFSET
,
1545 target
->rel_dyn_section(layout
),
1546 elfcpp::R_386_TLS_TPOFF
);
1548 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1549 unsupported_reloc_global(object
, r_type
, gsym
);
1552 case elfcpp::R_386_TLS_DESC_CALL
:
1555 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1556 if (optimized_type
== tls::TLSOPT_NONE
)
1558 // Create a GOT entry for the module index.
1559 target
->got_mod_index_entry(symtab
, layout
, object
);
1561 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1562 unsupported_reloc_global(object
, r_type
, gsym
);
1565 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1568 case elfcpp::R_386_TLS_IE
: // Initial-exec
1569 case elfcpp::R_386_TLS_IE_32
:
1570 case elfcpp::R_386_TLS_GOTIE
:
1571 layout
->set_has_static_tls();
1572 if (optimized_type
== tls::TLSOPT_NONE
)
1574 // For the R_386_TLS_IE relocation, we need to create a
1575 // dynamic relocation when building a shared library.
1576 if (r_type
== elfcpp::R_386_TLS_IE
1577 && parameters
->options().shared())
1579 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1580 rel_dyn
->add_global_relative(gsym
, elfcpp::R_386_RELATIVE
,
1581 output_section
, object
,
1583 reloc
.get_r_offset());
1585 // Create a GOT entry for the tp-relative offset.
1586 Output_data_got
<32, false>* got
1587 = target
->got_section(symtab
, layout
);
1588 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_IE_32
1589 ? elfcpp::R_386_TLS_TPOFF32
1590 : elfcpp::R_386_TLS_TPOFF
);
1591 unsigned int got_type
= (r_type
== elfcpp::R_386_TLS_IE_32
1592 ? GOT_TYPE_TLS_OFFSET
1593 : GOT_TYPE_TLS_NOFFSET
);
1594 got
->add_global_with_rel(gsym
, got_type
,
1595 target
->rel_dyn_section(layout
),
1598 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1599 unsupported_reloc_global(object
, r_type
, gsym
);
1602 case elfcpp::R_386_TLS_LE
: // Local-exec
1603 case elfcpp::R_386_TLS_LE_32
:
1604 layout
->set_has_static_tls();
1605 if (parameters
->options().shared())
1607 // We need to create a dynamic relocation.
1608 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_LE_32
1609 ? elfcpp::R_386_TLS_TPOFF32
1610 : elfcpp::R_386_TLS_TPOFF
);
1611 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1612 rel_dyn
->add_global(gsym
, dyn_r_type
, output_section
, object
,
1613 data_shndx
, reloc
.get_r_offset());
1623 case elfcpp::R_386_32PLT
:
1624 case elfcpp::R_386_TLS_GD_32
:
1625 case elfcpp::R_386_TLS_GD_PUSH
:
1626 case elfcpp::R_386_TLS_GD_CALL
:
1627 case elfcpp::R_386_TLS_GD_POP
:
1628 case elfcpp::R_386_TLS_LDM_32
:
1629 case elfcpp::R_386_TLS_LDM_PUSH
:
1630 case elfcpp::R_386_TLS_LDM_CALL
:
1631 case elfcpp::R_386_TLS_LDM_POP
:
1632 case elfcpp::R_386_USED_BY_INTEL_200
:
1634 unsupported_reloc_global(object
, r_type
, gsym
);
1639 // Process relocations for gc.
1642 Target_i386::gc_process_relocs(Symbol_table
* symtab
,
1644 Sized_relobj
<32, false>* object
,
1645 unsigned int data_shndx
,
1647 const unsigned char* prelocs
,
1649 Output_section
* output_section
,
1650 bool needs_special_offset_handling
,
1651 size_t local_symbol_count
,
1652 const unsigned char* plocal_symbols
)
1654 gold::gc_process_relocs
<32, false, Target_i386
, elfcpp::SHT_REL
,
1656 Target_i386::Relocatable_size_for_reloc
>(
1665 needs_special_offset_handling
,
1670 // Scan relocations for a section.
1673 Target_i386::scan_relocs(Symbol_table
* symtab
,
1675 Sized_relobj
<32, false>* object
,
1676 unsigned int data_shndx
,
1677 unsigned int sh_type
,
1678 const unsigned char* prelocs
,
1680 Output_section
* output_section
,
1681 bool needs_special_offset_handling
,
1682 size_t local_symbol_count
,
1683 const unsigned char* plocal_symbols
)
1685 if (sh_type
== elfcpp::SHT_RELA
)
1687 gold_error(_("%s: unsupported RELA reloc section"),
1688 object
->name().c_str());
1692 gold::scan_relocs
<32, false, Target_i386
, elfcpp::SHT_REL
,
1702 needs_special_offset_handling
,
1707 // Finalize the sections.
1710 Target_i386::do_finalize_sections(
1712 const Input_objects
*,
1713 Symbol_table
* symtab
)
1715 const Reloc_section
* rel_plt
= (this->plt_
== NULL
1717 : this->plt_
->rel_plt());
1718 layout
->add_target_dynamic_tags(true, this->got_plt_
, rel_plt
,
1719 this->rel_dyn_
, true, false);
1721 // Emit any relocs we saved in an attempt to avoid generating COPY
1723 if (this->copy_relocs_
.any_saved_relocs())
1724 this->copy_relocs_
.emit(this->rel_dyn_section(layout
));
1726 // Set the size of the _GLOBAL_OFFSET_TABLE_ symbol to the size of
1727 // the .got.plt section.
1728 Symbol
* sym
= this->global_offset_table_
;
1731 uint32_t data_size
= this->got_plt_
->current_data_size();
1732 symtab
->get_sized_symbol
<32>(sym
)->set_symsize(data_size
);
1736 // Return whether a direct absolute static relocation needs to be applied.
1737 // In cases where Scan::local() or Scan::global() has created
1738 // a dynamic relocation other than R_386_RELATIVE, the addend
1739 // of the relocation is carried in the data, and we must not
1740 // apply the static relocation.
1743 Target_i386::Relocate::should_apply_static_reloc(const Sized_symbol
<32>* gsym
,
1746 Output_section
* output_section
)
1748 // If the output section is not allocated, then we didn't call
1749 // scan_relocs, we didn't create a dynamic reloc, and we must apply
1751 if ((output_section
->flags() & elfcpp::SHF_ALLOC
) == 0)
1754 // For local symbols, we will have created a non-RELATIVE dynamic
1755 // relocation only if (a) the output is position independent,
1756 // (b) the relocation is absolute (not pc- or segment-relative), and
1757 // (c) the relocation is not 32 bits wide.
1759 return !(parameters
->options().output_is_position_independent()
1760 && (ref_flags
& Symbol::ABSOLUTE_REF
)
1763 // For global symbols, we use the same helper routines used in the
1764 // scan pass. If we did not create a dynamic relocation, or if we
1765 // created a RELATIVE dynamic relocation, we should apply the static
1767 bool has_dyn
= gsym
->needs_dynamic_reloc(ref_flags
);
1768 bool is_rel
= (ref_flags
& Symbol::ABSOLUTE_REF
)
1769 && gsym
->can_use_relative_reloc(ref_flags
1770 & Symbol::FUNCTION_CALL
);
1771 return !has_dyn
|| is_rel
;
1774 // Perform a relocation.
1777 Target_i386::Relocate::relocate(const Relocate_info
<32, false>* relinfo
,
1778 Target_i386
* target
,
1779 Output_section
*output_section
,
1781 const elfcpp::Rel
<32, false>& rel
,
1782 unsigned int r_type
,
1783 const Sized_symbol
<32>* gsym
,
1784 const Symbol_value
<32>* psymval
,
1785 unsigned char* view
,
1786 elfcpp::Elf_types
<32>::Elf_Addr address
,
1787 section_size_type view_size
)
1789 if (this->skip_call_tls_get_addr_
)
1791 if ((r_type
!= elfcpp::R_386_PLT32
1792 && r_type
!= elfcpp::R_386_PC32
)
1794 || strcmp(gsym
->name(), "___tls_get_addr") != 0)
1795 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
1796 _("missing expected TLS relocation"));
1799 this->skip_call_tls_get_addr_
= false;
1804 // Pick the value to use for symbols defined in shared objects.
1805 Symbol_value
<32> symval
;
1807 && gsym
->use_plt_offset(r_type
== elfcpp::R_386_PC8
1808 || r_type
== elfcpp::R_386_PC16
1809 || r_type
== elfcpp::R_386_PC32
))
1811 symval
.set_output_value(target
->plt_section()->address()
1812 + gsym
->plt_offset());
1816 const Sized_relobj
<32, false>* object
= relinfo
->object
;
1818 // Get the GOT offset if needed.
1819 // The GOT pointer points to the end of the GOT section.
1820 // We need to subtract the size of the GOT section to get
1821 // the actual offset to use in the relocation.
1822 bool have_got_offset
= false;
1823 unsigned int got_offset
= 0;
1826 case elfcpp::R_386_GOT32
:
1829 gold_assert(gsym
->has_got_offset(GOT_TYPE_STANDARD
));
1830 got_offset
= (gsym
->got_offset(GOT_TYPE_STANDARD
)
1831 - target
->got_size());
1835 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
1836 gold_assert(object
->local_has_got_offset(r_sym
, GOT_TYPE_STANDARD
));
1837 got_offset
= (object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
)
1838 - target
->got_size());
1840 have_got_offset
= true;
1849 case elfcpp::R_386_NONE
:
1850 case elfcpp::R_386_GNU_VTINHERIT
:
1851 case elfcpp::R_386_GNU_VTENTRY
:
1854 case elfcpp::R_386_32
:
1855 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, true,
1857 Relocate_functions
<32, false>::rel32(view
, object
, psymval
);
1860 case elfcpp::R_386_PC32
:
1862 int ref_flags
= Symbol::NON_PIC_REF
;
1863 if (gsym
!= NULL
&& gsym
->is_func())
1864 ref_flags
|= Symbol::FUNCTION_CALL
;
1865 if (should_apply_static_reloc(gsym
, ref_flags
, true, output_section
))
1866 Relocate_functions
<32, false>::pcrel32(view
, object
, psymval
, address
);
1870 case elfcpp::R_386_16
:
1871 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, false,
1873 Relocate_functions
<32, false>::rel16(view
, object
, psymval
);
1876 case elfcpp::R_386_PC16
:
1878 int ref_flags
= Symbol::NON_PIC_REF
;
1879 if (gsym
!= NULL
&& gsym
->is_func())
1880 ref_flags
|= Symbol::FUNCTION_CALL
;
1881 if (should_apply_static_reloc(gsym
, ref_flags
, false, output_section
))
1882 Relocate_functions
<32, false>::pcrel16(view
, object
, psymval
, address
);
1886 case elfcpp::R_386_8
:
1887 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, false,
1889 Relocate_functions
<32, false>::rel8(view
, object
, psymval
);
1892 case elfcpp::R_386_PC8
:
1894 int ref_flags
= Symbol::NON_PIC_REF
;
1895 if (gsym
!= NULL
&& gsym
->is_func())
1896 ref_flags
|= Symbol::FUNCTION_CALL
;
1897 if (should_apply_static_reloc(gsym
, ref_flags
, false,
1899 Relocate_functions
<32, false>::pcrel8(view
, object
, psymval
, address
);
1903 case elfcpp::R_386_PLT32
:
1904 gold_assert(gsym
== NULL
1905 || gsym
->has_plt_offset()
1906 || gsym
->final_value_is_known()
1907 || (gsym
->is_defined()
1908 && !gsym
->is_from_dynobj()
1909 && !gsym
->is_preemptible()));
1910 Relocate_functions
<32, false>::pcrel32(view
, object
, psymval
, address
);
1913 case elfcpp::R_386_GOT32
:
1914 gold_assert(have_got_offset
);
1915 Relocate_functions
<32, false>::rel32(view
, got_offset
);
1918 case elfcpp::R_386_GOTOFF
:
1920 elfcpp::Elf_types
<32>::Elf_Addr value
;
1921 value
= (psymval
->value(object
, 0)
1922 - target
->got_plt_section()->address());
1923 Relocate_functions
<32, false>::rel32(view
, value
);
1927 case elfcpp::R_386_GOTPC
:
1929 elfcpp::Elf_types
<32>::Elf_Addr value
;
1930 value
= target
->got_plt_section()->address();
1931 Relocate_functions
<32, false>::pcrel32(view
, value
, address
);
1935 case elfcpp::R_386_COPY
:
1936 case elfcpp::R_386_GLOB_DAT
:
1937 case elfcpp::R_386_JUMP_SLOT
:
1938 case elfcpp::R_386_RELATIVE
:
1939 // These are outstanding tls relocs, which are unexpected when
1941 case elfcpp::R_386_TLS_TPOFF
:
1942 case elfcpp::R_386_TLS_DTPMOD32
:
1943 case elfcpp::R_386_TLS_DTPOFF32
:
1944 case elfcpp::R_386_TLS_TPOFF32
:
1945 case elfcpp::R_386_TLS_DESC
:
1946 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
1947 _("unexpected reloc %u in object file"),
1951 // These are initial tls relocs, which are expected when
1953 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1954 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
1955 case elfcpp::R_386_TLS_DESC_CALL
:
1956 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1957 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1958 case elfcpp::R_386_TLS_IE
: // Initial-exec
1959 case elfcpp::R_386_TLS_IE_32
:
1960 case elfcpp::R_386_TLS_GOTIE
:
1961 case elfcpp::R_386_TLS_LE
: // Local-exec
1962 case elfcpp::R_386_TLS_LE_32
:
1963 this->relocate_tls(relinfo
, target
, relnum
, rel
, r_type
, gsym
, psymval
,
1964 view
, address
, view_size
);
1967 case elfcpp::R_386_32PLT
:
1968 case elfcpp::R_386_TLS_GD_32
:
1969 case elfcpp::R_386_TLS_GD_PUSH
:
1970 case elfcpp::R_386_TLS_GD_CALL
:
1971 case elfcpp::R_386_TLS_GD_POP
:
1972 case elfcpp::R_386_TLS_LDM_32
:
1973 case elfcpp::R_386_TLS_LDM_PUSH
:
1974 case elfcpp::R_386_TLS_LDM_CALL
:
1975 case elfcpp::R_386_TLS_LDM_POP
:
1976 case elfcpp::R_386_USED_BY_INTEL_200
:
1978 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
1979 _("unsupported reloc %u"),
1987 // Perform a TLS relocation.
1990 Target_i386::Relocate::relocate_tls(const Relocate_info
<32, false>* relinfo
,
1991 Target_i386
* target
,
1993 const elfcpp::Rel
<32, false>& rel
,
1994 unsigned int r_type
,
1995 const Sized_symbol
<32>* gsym
,
1996 const Symbol_value
<32>* psymval
,
1997 unsigned char* view
,
1998 elfcpp::Elf_types
<32>::Elf_Addr
,
1999 section_size_type view_size
)
2001 Output_segment
* tls_segment
= relinfo
->layout
->tls_segment();
2003 const Sized_relobj
<32, false>* object
= relinfo
->object
;
2005 elfcpp::Elf_types
<32>::Elf_Addr value
= psymval
->value(object
, 0);
2007 const bool is_final
= (gsym
== NULL
2008 ? !parameters
->options().shared()
2009 : gsym
->final_value_is_known());
2010 const tls::Tls_optimization optimized_type
2011 = Target_i386::optimize_tls_reloc(is_final
, r_type
);
2014 case elfcpp::R_386_TLS_GD
: // Global-dynamic
2015 if (optimized_type
== tls::TLSOPT_TO_LE
)
2017 gold_assert(tls_segment
!= NULL
);
2018 this->tls_gd_to_le(relinfo
, relnum
, tls_segment
,
2019 rel
, r_type
, value
, view
,
2025 unsigned int got_type
= (optimized_type
== tls::TLSOPT_TO_IE
2026 ? GOT_TYPE_TLS_NOFFSET
2027 : GOT_TYPE_TLS_PAIR
);
2028 unsigned int got_offset
;
2031 gold_assert(gsym
->has_got_offset(got_type
));
2032 got_offset
= gsym
->got_offset(got_type
) - target
->got_size();
2036 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
2037 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
2038 got_offset
= (object
->local_got_offset(r_sym
, got_type
)
2039 - target
->got_size());
2041 if (optimized_type
== tls::TLSOPT_TO_IE
)
2043 gold_assert(tls_segment
!= NULL
);
2044 this->tls_gd_to_ie(relinfo
, relnum
, tls_segment
, rel
, r_type
,
2045 got_offset
, view
, view_size
);
2048 else if (optimized_type
== tls::TLSOPT_NONE
)
2050 // Relocate the field with the offset of the pair of GOT
2052 Relocate_functions
<32, false>::rel32(view
, got_offset
);
2056 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2057 _("unsupported reloc %u"),
2061 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
2062 case elfcpp::R_386_TLS_DESC_CALL
:
2063 this->local_dynamic_type_
= LOCAL_DYNAMIC_GNU
;
2064 if (optimized_type
== tls::TLSOPT_TO_LE
)
2066 gold_assert(tls_segment
!= NULL
);
2067 this->tls_desc_gd_to_le(relinfo
, relnum
, tls_segment
,
2068 rel
, r_type
, value
, view
,
2074 unsigned int got_type
= (optimized_type
== tls::TLSOPT_TO_IE
2075 ? GOT_TYPE_TLS_NOFFSET
2076 : GOT_TYPE_TLS_DESC
);
2077 unsigned int got_offset
= 0;
2078 if (r_type
== elfcpp::R_386_TLS_GOTDESC
2079 && optimized_type
== tls::TLSOPT_NONE
)
2081 // We created GOT entries in the .got.tlsdesc portion of
2082 // the .got.plt section, but the offset stored in the
2083 // symbol is the offset within .got.tlsdesc.
2084 got_offset
= (target
->got_size()
2085 + target
->got_plt_section()->data_size());
2089 gold_assert(gsym
->has_got_offset(got_type
));
2090 got_offset
+= gsym
->got_offset(got_type
) - target
->got_size();
2094 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
2095 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
2096 got_offset
+= (object
->local_got_offset(r_sym
, got_type
)
2097 - target
->got_size());
2099 if (optimized_type
== tls::TLSOPT_TO_IE
)
2101 gold_assert(tls_segment
!= NULL
);
2102 this->tls_desc_gd_to_ie(relinfo
, relnum
, tls_segment
, rel
, r_type
,
2103 got_offset
, view
, view_size
);
2106 else if (optimized_type
== tls::TLSOPT_NONE
)
2108 if (r_type
== elfcpp::R_386_TLS_GOTDESC
)
2110 // Relocate the field with the offset of the pair of GOT
2112 Relocate_functions
<32, false>::rel32(view
, got_offset
);
2117 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2118 _("unsupported reloc %u"),
2122 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
2123 if (this->local_dynamic_type_
== LOCAL_DYNAMIC_SUN
)
2125 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2126 _("both SUN and GNU model "
2127 "TLS relocations"));
2130 this->local_dynamic_type_
= LOCAL_DYNAMIC_GNU
;
2131 if (optimized_type
== tls::TLSOPT_TO_LE
)
2133 gold_assert(tls_segment
!= NULL
);
2134 this->tls_ld_to_le(relinfo
, relnum
, tls_segment
, rel
, r_type
,
2135 value
, view
, view_size
);
2138 else if (optimized_type
== tls::TLSOPT_NONE
)
2140 // Relocate the field with the offset of the GOT entry for
2141 // the module index.
2142 unsigned int got_offset
;
2143 got_offset
= (target
->got_mod_index_entry(NULL
, NULL
, NULL
)
2144 - target
->got_size());
2145 Relocate_functions
<32, false>::rel32(view
, got_offset
);
2148 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2149 _("unsupported reloc %u"),
2153 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
2154 if (optimized_type
== tls::TLSOPT_TO_LE
)
2156 // This reloc can appear in debugging sections, in which
2157 // case we must not convert to local-exec. We decide what
2158 // to do based on whether the section is marked as
2159 // containing executable code. That is what the GNU linker
2161 elfcpp::Shdr
<32, false> shdr(relinfo
->data_shdr
);
2162 if ((shdr
.get_sh_flags() & elfcpp::SHF_EXECINSTR
) != 0)
2164 gold_assert(tls_segment
!= NULL
);
2165 value
-= tls_segment
->memsz();
2168 Relocate_functions
<32, false>::rel32(view
, value
);
2171 case elfcpp::R_386_TLS_IE
: // Initial-exec
2172 case elfcpp::R_386_TLS_GOTIE
:
2173 case elfcpp::R_386_TLS_IE_32
:
2174 if (optimized_type
== tls::TLSOPT_TO_LE
)
2176 gold_assert(tls_segment
!= NULL
);
2177 Target_i386::Relocate::tls_ie_to_le(relinfo
, relnum
, tls_segment
,
2178 rel
, r_type
, value
, view
,
2182 else if (optimized_type
== tls::TLSOPT_NONE
)
2184 // Relocate the field with the offset of the GOT entry for
2185 // the tp-relative offset of the symbol.
2186 unsigned int got_type
= (r_type
== elfcpp::R_386_TLS_IE_32
2187 ? GOT_TYPE_TLS_OFFSET
2188 : GOT_TYPE_TLS_NOFFSET
);
2189 unsigned int got_offset
;
2192 gold_assert(gsym
->has_got_offset(got_type
));
2193 got_offset
= gsym
->got_offset(got_type
);
2197 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
2198 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
2199 got_offset
= object
->local_got_offset(r_sym
, got_type
);
2201 // For the R_386_TLS_IE relocation, we need to apply the
2202 // absolute address of the GOT entry.
2203 if (r_type
== elfcpp::R_386_TLS_IE
)
2204 got_offset
+= target
->got_plt_section()->address();
2205 // All GOT offsets are relative to the end of the GOT.
2206 got_offset
-= target
->got_size();
2207 Relocate_functions
<32, false>::rel32(view
, got_offset
);
2210 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2211 _("unsupported reloc %u"),
2215 case elfcpp::R_386_TLS_LE
: // Local-exec
2216 // If we're creating a shared library, a dynamic relocation will
2217 // have been created for this location, so do not apply it now.
2218 if (!parameters
->options().shared())
2220 gold_assert(tls_segment
!= NULL
);
2221 value
-= tls_segment
->memsz();
2222 Relocate_functions
<32, false>::rel32(view
, value
);
2226 case elfcpp::R_386_TLS_LE_32
:
2227 // If we're creating a shared library, a dynamic relocation will
2228 // have been created for this location, so do not apply it now.
2229 if (!parameters
->options().shared())
2231 gold_assert(tls_segment
!= NULL
);
2232 value
= tls_segment
->memsz() - value
;
2233 Relocate_functions
<32, false>::rel32(view
, value
);
2239 // Do a relocation in which we convert a TLS General-Dynamic to a
2243 Target_i386::Relocate::tls_gd_to_le(const Relocate_info
<32, false>* relinfo
,
2245 Output_segment
* tls_segment
,
2246 const elfcpp::Rel
<32, false>& rel
,
2248 elfcpp::Elf_types
<32>::Elf_Addr value
,
2249 unsigned char* view
,
2250 section_size_type view_size
)
2252 // leal foo(,%reg,1),%eax; call ___tls_get_addr
2253 // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
2254 // leal foo(%reg),%eax; call ___tls_get_addr
2255 // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
2257 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2258 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 9);
2260 unsigned char op1
= view
[-1];
2261 unsigned char op2
= view
[-2];
2263 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2264 op2
== 0x8d || op2
== 0x04);
2265 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[4] == 0xe8);
2271 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -3);
2272 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[-3] == 0x8d);
2273 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2274 ((op1
& 0xc7) == 0x05 && op1
!= (4 << 3)));
2275 memcpy(view
- 3, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
2279 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2280 (op1
& 0xf8) == 0x80 && (op1
& 7) != 4);
2281 if (rel
.get_r_offset() + 9 < view_size
2284 // There is a trailing nop. Use the size byte subl.
2285 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
2290 // Use the five byte subl.
2291 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
2295 value
= tls_segment
->memsz() - value
;
2296 Relocate_functions
<32, false>::rel32(view
+ roff
, value
);
2298 // The next reloc should be a PLT32 reloc against __tls_get_addr.
2300 this->skip_call_tls_get_addr_
= true;
2303 // Do a relocation in which we convert a TLS General-Dynamic to an
2307 Target_i386::Relocate::tls_gd_to_ie(const Relocate_info
<32, false>* relinfo
,
2310 const elfcpp::Rel
<32, false>& rel
,
2312 elfcpp::Elf_types
<32>::Elf_Addr value
,
2313 unsigned char* view
,
2314 section_size_type view_size
)
2316 // leal foo(,%ebx,1),%eax; call ___tls_get_addr
2317 // ==> movl %gs:0,%eax; addl foo@gotntpoff(%ebx),%eax
2319 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2320 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 9);
2322 unsigned char op1
= view
[-1];
2323 unsigned char op2
= view
[-2];
2325 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2326 op2
== 0x8d || op2
== 0x04);
2327 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[4] == 0xe8);
2331 // FIXME: For now, support only the first (SIB) form.
2332 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), op2
== 0x04);
2336 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -3);
2337 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[-3] == 0x8d);
2338 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2339 ((op1
& 0xc7) == 0x05 && op1
!= (4 << 3)));
2340 memcpy(view
- 3, "\x65\xa1\0\0\0\0\x03\x83\0\0\0", 12);
2344 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2345 (op1
& 0xf8) == 0x80 && (op1
& 7) != 4);
2346 if (rel
.get_r_offset() + 9 < view_size
2349 // FIXME: This is not the right instruction sequence.
2350 // There is a trailing nop. Use the size byte subl.
2351 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
2356 // FIXME: This is not the right instruction sequence.
2357 // Use the five byte subl.
2358 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
2362 Relocate_functions
<32, false>::rel32(view
+ roff
, value
);
2364 // The next reloc should be a PLT32 reloc against __tls_get_addr.
2366 this->skip_call_tls_get_addr_
= true;
2369 // Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL
2370 // General-Dynamic to a Local-Exec.
2373 Target_i386::Relocate::tls_desc_gd_to_le(
2374 const Relocate_info
<32, false>* relinfo
,
2376 Output_segment
* tls_segment
,
2377 const elfcpp::Rel
<32, false>& rel
,
2378 unsigned int r_type
,
2379 elfcpp::Elf_types
<32>::Elf_Addr value
,
2380 unsigned char* view
,
2381 section_size_type view_size
)
2383 if (r_type
== elfcpp::R_386_TLS_GOTDESC
)
2385 // leal foo@TLSDESC(%ebx), %eax
2386 // ==> leal foo@NTPOFF, %eax
2387 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2388 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
2389 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2390 view
[-2] == 0x8d && view
[-1] == 0x83);
2392 value
-= tls_segment
->memsz();
2393 Relocate_functions
<32, false>::rel32(view
, value
);
2397 // call *foo@TLSCALL(%eax)
2399 gold_assert(r_type
== elfcpp::R_386_TLS_DESC_CALL
);
2400 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 2);
2401 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2402 view
[0] == 0xff && view
[1] == 0x10);
2408 // Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL
2409 // General-Dynamic to an Initial-Exec.
2412 Target_i386::Relocate::tls_desc_gd_to_ie(
2413 const Relocate_info
<32, false>* relinfo
,
2416 const elfcpp::Rel
<32, false>& rel
,
2417 unsigned int r_type
,
2418 elfcpp::Elf_types
<32>::Elf_Addr value
,
2419 unsigned char* view
,
2420 section_size_type view_size
)
2422 if (r_type
== elfcpp::R_386_TLS_GOTDESC
)
2424 // leal foo@TLSDESC(%ebx), %eax
2425 // ==> movl foo@GOTNTPOFF(%ebx), %eax
2426 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2427 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
2428 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2429 view
[-2] == 0x8d && view
[-1] == 0x83);
2431 Relocate_functions
<32, false>::rel32(view
, value
);
2435 // call *foo@TLSCALL(%eax)
2437 gold_assert(r_type
== elfcpp::R_386_TLS_DESC_CALL
);
2438 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 2);
2439 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2440 view
[0] == 0xff && view
[1] == 0x10);
2446 // Do a relocation in which we convert a TLS Local-Dynamic to a
2450 Target_i386::Relocate::tls_ld_to_le(const Relocate_info
<32, false>* relinfo
,
2453 const elfcpp::Rel
<32, false>& rel
,
2455 elfcpp::Elf_types
<32>::Elf_Addr
,
2456 unsigned char* view
,
2457 section_size_type view_size
)
2459 // leal foo(%reg), %eax; call ___tls_get_addr
2460 // ==> movl %gs:0,%eax; nop; leal 0(%esi,1),%esi
2462 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2463 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 9);
2465 // FIXME: Does this test really always pass?
2466 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2467 view
[-2] == 0x8d && view
[-1] == 0x83);
2469 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[4] == 0xe8);
2471 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x90\x8d\x74\x26\0", 11);
2473 // The next reloc should be a PLT32 reloc against __tls_get_addr.
2475 this->skip_call_tls_get_addr_
= true;
2478 // Do a relocation in which we convert a TLS Initial-Exec to a
2482 Target_i386::Relocate::tls_ie_to_le(const Relocate_info
<32, false>* relinfo
,
2484 Output_segment
* tls_segment
,
2485 const elfcpp::Rel
<32, false>& rel
,
2486 unsigned int r_type
,
2487 elfcpp::Elf_types
<32>::Elf_Addr value
,
2488 unsigned char* view
,
2489 section_size_type view_size
)
2491 // We have to actually change the instructions, which means that we
2492 // need to examine the opcodes to figure out which instruction we
2494 if (r_type
== elfcpp::R_386_TLS_IE
)
2496 // movl %gs:XX,%eax ==> movl $YY,%eax
2497 // movl %gs:XX,%reg ==> movl $YY,%reg
2498 // addl %gs:XX,%reg ==> addl $YY,%reg
2499 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -1);
2500 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
2502 unsigned char op1
= view
[-1];
2505 // movl XX,%eax ==> movl $YY,%eax
2510 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2512 unsigned char op2
= view
[-2];
2515 // movl XX,%reg ==> movl $YY,%reg
2516 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2517 (op1
& 0xc7) == 0x05);
2519 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
2521 else if (op2
== 0x03)
2523 // addl XX,%reg ==> addl $YY,%reg
2524 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2525 (op1
& 0xc7) == 0x05);
2527 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
2530 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), 0);
2535 // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2
2536 // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2
2537 // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2
2538 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2539 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
2541 unsigned char op1
= view
[-1];
2542 unsigned char op2
= view
[-2];
2543 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2544 (op1
& 0xc0) == 0x80 && (op1
& 7) != 4);
2547 // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2
2549 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
2551 else if (op2
== 0x2b)
2553 // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2
2555 view
[-1] = 0xe8 | ((op1
>> 3) & 7);
2557 else if (op2
== 0x03)
2559 // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2
2561 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
2564 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), 0);
2567 value
= tls_segment
->memsz() - value
;
2568 if (r_type
== elfcpp::R_386_TLS_IE
|| r_type
== elfcpp::R_386_TLS_GOTIE
)
2571 Relocate_functions
<32, false>::rel32(view
, value
);
2574 // Relocate section data.
2577 Target_i386::relocate_section(const Relocate_info
<32, false>* relinfo
,
2578 unsigned int sh_type
,
2579 const unsigned char* prelocs
,
2581 Output_section
* output_section
,
2582 bool needs_special_offset_handling
,
2583 unsigned char* view
,
2584 elfcpp::Elf_types
<32>::Elf_Addr address
,
2585 section_size_type view_size
,
2586 const Reloc_symbol_changes
* reloc_symbol_changes
)
2588 gold_assert(sh_type
== elfcpp::SHT_REL
);
2590 gold::relocate_section
<32, false, Target_i386
, elfcpp::SHT_REL
,
2591 Target_i386::Relocate
>(
2597 needs_special_offset_handling
,
2601 reloc_symbol_changes
);
2604 // Return the size of a relocation while scanning during a relocatable
2608 Target_i386::Relocatable_size_for_reloc::get_size_for_reloc(
2609 unsigned int r_type
,
2614 case elfcpp::R_386_NONE
:
2615 case elfcpp::R_386_GNU_VTINHERIT
:
2616 case elfcpp::R_386_GNU_VTENTRY
:
2617 case elfcpp::R_386_TLS_GD
: // Global-dynamic
2618 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
2619 case elfcpp::R_386_TLS_DESC_CALL
:
2620 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
2621 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
2622 case elfcpp::R_386_TLS_IE
: // Initial-exec
2623 case elfcpp::R_386_TLS_IE_32
:
2624 case elfcpp::R_386_TLS_GOTIE
:
2625 case elfcpp::R_386_TLS_LE
: // Local-exec
2626 case elfcpp::R_386_TLS_LE_32
:
2629 case elfcpp::R_386_32
:
2630 case elfcpp::R_386_PC32
:
2631 case elfcpp::R_386_GOT32
:
2632 case elfcpp::R_386_PLT32
:
2633 case elfcpp::R_386_GOTOFF
:
2634 case elfcpp::R_386_GOTPC
:
2637 case elfcpp::R_386_16
:
2638 case elfcpp::R_386_PC16
:
2641 case elfcpp::R_386_8
:
2642 case elfcpp::R_386_PC8
:
2645 // These are relocations which should only be seen by the
2646 // dynamic linker, and should never be seen here.
2647 case elfcpp::R_386_COPY
:
2648 case elfcpp::R_386_GLOB_DAT
:
2649 case elfcpp::R_386_JUMP_SLOT
:
2650 case elfcpp::R_386_RELATIVE
:
2651 case elfcpp::R_386_TLS_TPOFF
:
2652 case elfcpp::R_386_TLS_DTPMOD32
:
2653 case elfcpp::R_386_TLS_DTPOFF32
:
2654 case elfcpp::R_386_TLS_TPOFF32
:
2655 case elfcpp::R_386_TLS_DESC
:
2656 object
->error(_("unexpected reloc %u in object file"), r_type
);
2659 case elfcpp::R_386_32PLT
:
2660 case elfcpp::R_386_TLS_GD_32
:
2661 case elfcpp::R_386_TLS_GD_PUSH
:
2662 case elfcpp::R_386_TLS_GD_CALL
:
2663 case elfcpp::R_386_TLS_GD_POP
:
2664 case elfcpp::R_386_TLS_LDM_32
:
2665 case elfcpp::R_386_TLS_LDM_PUSH
:
2666 case elfcpp::R_386_TLS_LDM_CALL
:
2667 case elfcpp::R_386_TLS_LDM_POP
:
2668 case elfcpp::R_386_USED_BY_INTEL_200
:
2670 object
->error(_("unsupported reloc %u in object file"), r_type
);
2675 // Scan the relocs during a relocatable link.
2678 Target_i386::scan_relocatable_relocs(Symbol_table
* symtab
,
2680 Sized_relobj
<32, false>* object
,
2681 unsigned int data_shndx
,
2682 unsigned int sh_type
,
2683 const unsigned char* prelocs
,
2685 Output_section
* output_section
,
2686 bool needs_special_offset_handling
,
2687 size_t local_symbol_count
,
2688 const unsigned char* plocal_symbols
,
2689 Relocatable_relocs
* rr
)
2691 gold_assert(sh_type
== elfcpp::SHT_REL
);
2693 typedef gold::Default_scan_relocatable_relocs
<elfcpp::SHT_REL
,
2694 Relocatable_size_for_reloc
> Scan_relocatable_relocs
;
2696 gold::scan_relocatable_relocs
<32, false, elfcpp::SHT_REL
,
2697 Scan_relocatable_relocs
>(
2705 needs_special_offset_handling
,
2711 // Relocate a section during a relocatable link.
2714 Target_i386::relocate_for_relocatable(
2715 const Relocate_info
<32, false>* relinfo
,
2716 unsigned int sh_type
,
2717 const unsigned char* prelocs
,
2719 Output_section
* output_section
,
2720 off_t offset_in_output_section
,
2721 const Relocatable_relocs
* rr
,
2722 unsigned char* view
,
2723 elfcpp::Elf_types
<32>::Elf_Addr view_address
,
2724 section_size_type view_size
,
2725 unsigned char* reloc_view
,
2726 section_size_type reloc_view_size
)
2728 gold_assert(sh_type
== elfcpp::SHT_REL
);
2730 gold::relocate_for_relocatable
<32, false, elfcpp::SHT_REL
>(
2735 offset_in_output_section
,
2744 // Return the value to use for a dynamic which requires special
2745 // treatment. This is how we support equality comparisons of function
2746 // pointers across shared library boundaries, as described in the
2747 // processor specific ABI supplement.
2750 Target_i386::do_dynsym_value(const Symbol
* gsym
) const
2752 gold_assert(gsym
->is_from_dynobj() && gsym
->has_plt_offset());
2753 return this->plt_section()->address() + gsym
->plt_offset();
2756 // Return a string used to fill a code section with nops to take up
2757 // the specified length.
2760 Target_i386::do_code_fill(section_size_type length
) const
2764 // Build a jmp instruction to skip over the bytes.
2765 unsigned char jmp
[5];
2767 elfcpp::Swap_unaligned
<32, false>::writeval(jmp
+ 1, length
- 5);
2768 return (std::string(reinterpret_cast<char*>(&jmp
[0]), 5)
2769 + std::string(length
- 5, '\0'));
2772 // Nop sequences of various lengths.
2773 const char nop1
[1] = { 0x90 }; // nop
2774 const char nop2
[2] = { 0x66, 0x90 }; // xchg %ax %ax
2775 const char nop3
[3] = { 0x8d, 0x76, 0x00 }; // leal 0(%esi),%esi
2776 const char nop4
[4] = { 0x8d, 0x74, 0x26, 0x00}; // leal 0(%esi,1),%esi
2777 const char nop5
[5] = { 0x90, 0x8d, 0x74, 0x26, // nop
2778 0x00 }; // leal 0(%esi,1),%esi
2779 const char nop6
[6] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2781 const char nop7
[7] = { 0x8d, 0xb4, 0x26, 0x00, // leal 0L(%esi,1),%esi
2783 const char nop8
[8] = { 0x90, 0x8d, 0xb4, 0x26, // nop
2784 0x00, 0x00, 0x00, 0x00 }; // leal 0L(%esi,1),%esi
2785 const char nop9
[9] = { 0x89, 0xf6, 0x8d, 0xbc, // movl %esi,%esi
2786 0x27, 0x00, 0x00, 0x00, // leal 0L(%edi,1),%edi
2788 const char nop10
[10] = { 0x8d, 0x76, 0x00, 0x8d, // leal 0(%esi),%esi
2789 0xbc, 0x27, 0x00, 0x00, // leal 0L(%edi,1),%edi
2791 const char nop11
[11] = { 0x8d, 0x74, 0x26, 0x00, // leal 0(%esi,1),%esi
2792 0x8d, 0xbc, 0x27, 0x00, // leal 0L(%edi,1),%edi
2794 const char nop12
[12] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2795 0x00, 0x00, 0x8d, 0xbf, // leal 0L(%edi),%edi
2796 0x00, 0x00, 0x00, 0x00 };
2797 const char nop13
[13] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2798 0x00, 0x00, 0x8d, 0xbc, // leal 0L(%edi,1),%edi
2799 0x27, 0x00, 0x00, 0x00,
2801 const char nop14
[14] = { 0x8d, 0xb4, 0x26, 0x00, // leal 0L(%esi,1),%esi
2802 0x00, 0x00, 0x00, 0x8d, // leal 0L(%edi,1),%edi
2803 0xbc, 0x27, 0x00, 0x00,
2805 const char nop15
[15] = { 0xeb, 0x0d, 0x90, 0x90, // jmp .+15
2806 0x90, 0x90, 0x90, 0x90, // nop,nop,nop,...
2807 0x90, 0x90, 0x90, 0x90,
2810 const char* nops
[16] = {
2812 nop1
, nop2
, nop3
, nop4
, nop5
, nop6
, nop7
,
2813 nop8
, nop9
, nop10
, nop11
, nop12
, nop13
, nop14
, nop15
2816 return std::string(nops
[length
], length
);
2819 // Return whether SYM should be treated as a call to a non-split
2820 // function. We don't want that to be true of a call to a
2821 // get_pc_thunk function.
2824 Target_i386::do_is_call_to_non_split(const Symbol
* sym
, unsigned int) const
2826 return (sym
->type() == elfcpp::STT_FUNC
2827 && !is_prefix_of("__i686.get_pc_thunk.", sym
->name()));
2830 // FNOFFSET in section SHNDX in OBJECT is the start of a function
2831 // compiled with -fstack-split. The function calls non-stack-split
2832 // code. We have to change the function so that it always ensures
2833 // that it has enough stack space to run some random function.
2836 Target_i386::do_calls_non_split(Relobj
* object
, unsigned int shndx
,
2837 section_offset_type fnoffset
,
2838 section_size_type fnsize
,
2839 unsigned char* view
,
2840 section_size_type view_size
,
2842 std::string
* to
) const
2844 // The function starts with a comparison of the stack pointer and a
2845 // field in the TCB. This is followed by a jump.
2848 if (this->match_view(view
, view_size
, fnoffset
, "\x65\x3b\x25", 3)
2851 // We will call __morestack if the carry flag is set after this
2852 // comparison. We turn the comparison into an stc instruction
2854 view
[fnoffset
] = '\xf9';
2855 this->set_view_to_nop(view
, view_size
, fnoffset
+ 1, 6);
2857 // lea NN(%esp),%ecx
2858 // lea NN(%esp),%edx
2859 else if ((this->match_view(view
, view_size
, fnoffset
, "\x8d\x8c\x24", 3)
2860 || this->match_view(view
, view_size
, fnoffset
, "\x8d\x94\x24", 3))
2863 // This is loading an offset from the stack pointer for a
2864 // comparison. The offset is negative, so we decrease the
2865 // offset by the amount of space we need for the stack. This
2866 // means we will avoid calling __morestack if there happens to
2867 // be plenty of space on the stack already.
2868 unsigned char* pval
= view
+ fnoffset
+ 3;
2869 uint32_t val
= elfcpp::Swap_unaligned
<32, false>::readval(pval
);
2870 val
-= parameters
->options().split_stack_adjust_size();
2871 elfcpp::Swap_unaligned
<32, false>::writeval(pval
, val
);
2875 if (!object
->has_no_split_stack())
2876 object
->error(_("failed to match split-stack sequence at "
2877 "section %u offset %0zx"),
2878 shndx
, static_cast<size_t>(fnoffset
));
2882 // We have to change the function so that it calls
2883 // __morestack_non_split instead of __morestack. The former will
2884 // allocate additional stack space.
2885 *from
= "__morestack";
2886 *to
= "__morestack_non_split";
2889 // The selector for i386 object files.
2891 class Target_selector_i386
: public Target_selector_freebsd
2894 Target_selector_i386()
2895 : Target_selector_freebsd(elfcpp::EM_386
, 32, false,
2896 "elf32-i386", "elf32-i386-freebsd")
2900 do_instantiate_target()
2901 { return new Target_i386(); }
2904 Target_selector_i386 target_selector_i386
;
2906 } // End anonymous namespace.