1 // i386.cc -- i386 target support for gold.
3 // Copyright 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
4 // Written by Ian Lance Taylor <iant@google.com>.
6 // This file is part of gold.
8 // This program is free software; you can redistribute it and/or modify
9 // it under the terms of the GNU General Public License as published by
10 // the Free Software Foundation; either version 3 of the License, or
11 // (at your option) any later version.
13 // This program is distributed in the hope that it will be useful,
14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 // GNU General Public License for more details.
18 // You should have received a copy of the GNU General Public License
19 // along with this program; if not, write to the Free Software
20 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
21 // MA 02110-1301, USA.
28 #include "parameters.h"
35 #include "copy-relocs.h"
37 #include "target-reloc.h"
38 #include "target-select.h"
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
), global_offset_table_(NULL
),
63 rel_dyn_(NULL
), copy_relocs_(elfcpp::R_386_COPY
), dynbss_(NULL
),
64 got_mod_index_offset_(-1U), tls_base_symbol_defined_(false)
68 can_check_for_function_pointers() const
71 // Process the relocations to determine unreferenced sections for
72 // garbage collection.
74 gc_process_relocs(Symbol_table
* symtab
,
76 Sized_relobj
<32, false>* object
,
77 unsigned int data_shndx
,
79 const unsigned char* prelocs
,
81 Output_section
* output_section
,
82 bool needs_special_offset_handling
,
83 size_t local_symbol_count
,
84 const unsigned char* plocal_symbols
);
86 // Scan the relocations to look for symbol adjustments.
88 scan_relocs(Symbol_table
* symtab
,
90 Sized_relobj
<32, false>* object
,
91 unsigned int data_shndx
,
93 const unsigned char* prelocs
,
95 Output_section
* output_section
,
96 bool needs_special_offset_handling
,
97 size_t local_symbol_count
,
98 const unsigned char* plocal_symbols
);
100 // Finalize the sections.
102 do_finalize_sections(Layout
*, const Input_objects
*, Symbol_table
*);
104 // Return the value to use for a dynamic which requires special
107 do_dynsym_value(const Symbol
*) const;
109 // Relocate a section.
111 relocate_section(const Relocate_info
<32, false>*,
112 unsigned int sh_type
,
113 const unsigned char* prelocs
,
115 Output_section
* output_section
,
116 bool needs_special_offset_handling
,
118 elfcpp::Elf_types
<32>::Elf_Addr view_address
,
119 section_size_type view_size
,
120 const Reloc_symbol_changes
*);
122 // Scan the relocs during a relocatable link.
124 scan_relocatable_relocs(Symbol_table
* symtab
,
126 Sized_relobj
<32, false>* object
,
127 unsigned int data_shndx
,
128 unsigned int sh_type
,
129 const unsigned char* prelocs
,
131 Output_section
* output_section
,
132 bool needs_special_offset_handling
,
133 size_t local_symbol_count
,
134 const unsigned char* plocal_symbols
,
135 Relocatable_relocs
*);
137 // Relocate a section during a relocatable link.
139 relocate_for_relocatable(const Relocate_info
<32, false>*,
140 unsigned int sh_type
,
141 const unsigned char* prelocs
,
143 Output_section
* output_section
,
144 off_t offset_in_output_section
,
145 const Relocatable_relocs
*,
147 elfcpp::Elf_types
<32>::Elf_Addr view_address
,
148 section_size_type view_size
,
149 unsigned char* reloc_view
,
150 section_size_type reloc_view_size
);
152 // Return a string used to fill a code section with nops.
154 do_code_fill(section_size_type length
) const;
156 // Return whether SYM is defined by the ABI.
158 do_is_defined_by_abi(const Symbol
* sym
) const
159 { return strcmp(sym
->name(), "___tls_get_addr") == 0; }
161 // Return whether a symbol name implies a local label. The UnixWare
162 // 2.1 cc generates temporary symbols that start with .X, so we
163 // recognize them here. FIXME: do other SVR4 compilers also use .X?.
164 // If so, we should move the .X recognition into
165 // Target::do_is_local_label_name.
167 do_is_local_label_name(const char* name
) const
169 if (name
[0] == '.' && name
[1] == 'X')
171 return Target::do_is_local_label_name(name
);
174 // Return whether SYM is call to a non-split function.
176 do_is_call_to_non_split(const Symbol
* sym
, unsigned int) const;
178 // Adjust -fstack-split code which calls non-stack-split code.
180 do_calls_non_split(Relobj
* object
, unsigned int shndx
,
181 section_offset_type fnoffset
, section_size_type fnsize
,
182 unsigned char* view
, section_size_type view_size
,
183 std::string
* from
, std::string
* to
) const;
185 // Return the size of the GOT section.
189 gold_assert(this->got_
!= NULL
);
190 return this->got_
->data_size();
194 // The class which scans relocations.
198 local(Symbol_table
* symtab
, Layout
* layout
, Target_i386
* target
,
199 Sized_relobj
<32, false>* object
,
200 unsigned int data_shndx
,
201 Output_section
* output_section
,
202 const elfcpp::Rel
<32, false>& reloc
, unsigned int r_type
,
203 const elfcpp::Sym
<32, false>& lsym
);
206 global(Symbol_table
* symtab
, Layout
* layout
, Target_i386
* target
,
207 Sized_relobj
<32, false>* object
,
208 unsigned int data_shndx
,
209 Output_section
* output_section
,
210 const elfcpp::Rel
<32, false>& reloc
, unsigned int r_type
,
214 local_reloc_may_be_function_pointer(Symbol_table
* symtab
, Layout
* layout
,
216 Sized_relobj
<32, false>* object
,
217 unsigned int data_shndx
,
218 Output_section
* output_section
,
219 const elfcpp::Rel
<32, false>& reloc
,
221 const elfcpp::Sym
<32, false>& lsym
);
224 global_reloc_may_be_function_pointer(Symbol_table
* symtab
, Layout
* layout
,
226 Sized_relobj
<32, false>* object
,
227 unsigned int data_shndx
,
228 Output_section
* output_section
,
229 const elfcpp::Rel
<32, false>& reloc
,
234 possible_function_pointer_reloc(unsigned int r_type
);
237 unsupported_reloc_local(Sized_relobj
<32, false>*, unsigned int r_type
);
240 unsupported_reloc_global(Sized_relobj
<32, false>*, unsigned int r_type
,
244 // The class which implements relocation.
249 : skip_call_tls_get_addr_(false),
250 local_dynamic_type_(LOCAL_DYNAMIC_NONE
)
255 if (this->skip_call_tls_get_addr_
)
257 // FIXME: This needs to specify the location somehow.
258 gold_error(_("missing expected TLS relocation"));
262 // Return whether the static relocation needs to be applied.
264 should_apply_static_reloc(const Sized_symbol
<32>* gsym
,
267 Output_section
* output_section
);
269 // Do a relocation. Return false if the caller should not issue
270 // any warnings about this relocation.
272 relocate(const Relocate_info
<32, false>*, Target_i386
*, Output_section
*,
273 size_t relnum
, const elfcpp::Rel
<32, false>&,
274 unsigned int r_type
, const Sized_symbol
<32>*,
275 const Symbol_value
<32>*,
276 unsigned char*, elfcpp::Elf_types
<32>::Elf_Addr
,
280 // Do a TLS relocation.
282 relocate_tls(const Relocate_info
<32, false>*, Target_i386
* target
,
283 size_t relnum
, const elfcpp::Rel
<32, false>&,
284 unsigned int r_type
, const Sized_symbol
<32>*,
285 const Symbol_value
<32>*,
286 unsigned char*, elfcpp::Elf_types
<32>::Elf_Addr
,
289 // Do a TLS General-Dynamic to Initial-Exec transition.
291 tls_gd_to_ie(const Relocate_info
<32, false>*, size_t relnum
,
292 Output_segment
* tls_segment
,
293 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
294 elfcpp::Elf_types
<32>::Elf_Addr value
,
296 section_size_type view_size
);
298 // Do a TLS General-Dynamic to Local-Exec transition.
300 tls_gd_to_le(const Relocate_info
<32, false>*, size_t relnum
,
301 Output_segment
* tls_segment
,
302 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
303 elfcpp::Elf_types
<32>::Elf_Addr value
,
305 section_size_type view_size
);
307 // Do a TLS_GOTDESC or TLS_DESC_CALL General-Dynamic to Initial-Exec
310 tls_desc_gd_to_ie(const Relocate_info
<32, false>*, size_t relnum
,
311 Output_segment
* tls_segment
,
312 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
313 elfcpp::Elf_types
<32>::Elf_Addr value
,
315 section_size_type view_size
);
317 // Do a TLS_GOTDESC or TLS_DESC_CALL General-Dynamic to Local-Exec
320 tls_desc_gd_to_le(const Relocate_info
<32, false>*, size_t relnum
,
321 Output_segment
* tls_segment
,
322 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
323 elfcpp::Elf_types
<32>::Elf_Addr value
,
325 section_size_type view_size
);
327 // Do a TLS Local-Dynamic to Local-Exec transition.
329 tls_ld_to_le(const Relocate_info
<32, false>*, size_t relnum
,
330 Output_segment
* tls_segment
,
331 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
332 elfcpp::Elf_types
<32>::Elf_Addr value
,
334 section_size_type view_size
);
336 // Do a TLS Initial-Exec to Local-Exec transition.
338 tls_ie_to_le(const Relocate_info
<32, false>*, size_t relnum
,
339 Output_segment
* tls_segment
,
340 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
341 elfcpp::Elf_types
<32>::Elf_Addr value
,
343 section_size_type view_size
);
345 // We need to keep track of which type of local dynamic relocation
346 // we have seen, so that we can optimize R_386_TLS_LDO_32 correctly.
347 enum Local_dynamic_type
354 // This is set if we should skip the next reloc, which should be a
355 // PLT32 reloc against ___tls_get_addr.
356 bool skip_call_tls_get_addr_
;
357 // The type of local dynamic relocation we have seen in the section
358 // being relocated, if any.
359 Local_dynamic_type local_dynamic_type_
;
362 // A class which returns the size required for a relocation type,
363 // used while scanning relocs during a relocatable link.
364 class Relocatable_size_for_reloc
368 get_size_for_reloc(unsigned int, Relobj
*);
371 // Adjust TLS relocation type based on the options and whether this
372 // is a local symbol.
373 static tls::Tls_optimization
374 optimize_tls_reloc(bool is_final
, int r_type
);
376 // Get the GOT section, creating it if necessary.
377 Output_data_got
<32, false>*
378 got_section(Symbol_table
*, Layout
*);
380 // Get the GOT PLT section.
382 got_plt_section() const
384 gold_assert(this->got_plt_
!= NULL
);
385 return this->got_plt_
;
388 // Create a PLT entry for a global symbol.
390 make_plt_entry(Symbol_table
*, Layout
*, Symbol
*);
392 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
394 define_tls_base_symbol(Symbol_table
*, Layout
*);
396 // Create a GOT entry for the TLS module index.
398 got_mod_index_entry(Symbol_table
* symtab
, Layout
* layout
,
399 Sized_relobj
<32, false>* object
);
401 // Get the PLT section.
402 Output_data_plt_i386
*
405 gold_assert(this->plt_
!= NULL
);
409 // Get the dynamic reloc section, creating it if necessary.
411 rel_dyn_section(Layout
*);
413 // Get the section to use for TLS_DESC relocations.
415 rel_tls_desc_section(Layout
*) const;
417 // Add a potential copy relocation.
419 copy_reloc(Symbol_table
* symtab
, Layout
* layout
,
420 Sized_relobj
<32, false>* object
,
421 unsigned int shndx
, Output_section
* output_section
,
422 Symbol
* sym
, const elfcpp::Rel
<32, false>& reloc
)
424 this->copy_relocs_
.copy_reloc(symtab
, layout
,
425 symtab
->get_sized_symbol
<32>(sym
),
426 object
, shndx
, output_section
, reloc
,
427 this->rel_dyn_section(layout
));
430 // Information about this specific target which we pass to the
431 // general Target structure.
432 static const Target::Target_info i386_info
;
434 // The types of GOT entries needed for this platform.
437 GOT_TYPE_STANDARD
= 0, // GOT entry for a regular symbol
438 GOT_TYPE_TLS_NOFFSET
= 1, // GOT entry for negative TLS offset
439 GOT_TYPE_TLS_OFFSET
= 2, // GOT entry for positive TLS offset
440 GOT_TYPE_TLS_PAIR
= 3, // GOT entry for TLS module/offset pair
441 GOT_TYPE_TLS_DESC
= 4 // GOT entry for TLS_DESC pair
445 Output_data_got
<32, false>* got_
;
447 Output_data_plt_i386
* plt_
;
448 // The GOT PLT section.
449 Output_data_space
* got_plt_
;
450 // The _GLOBAL_OFFSET_TABLE_ symbol.
451 Symbol
* global_offset_table_
;
452 // The dynamic reloc section.
453 Reloc_section
* rel_dyn_
;
454 // Relocs saved to avoid a COPY reloc.
455 Copy_relocs
<elfcpp::SHT_REL
, 32, false> copy_relocs_
;
456 // Space for variables copied with a COPY reloc.
457 Output_data_space
* dynbss_
;
458 // Offset of the GOT entry for the TLS module index.
459 unsigned int got_mod_index_offset_
;
460 // True if the _TLS_MODULE_BASE_ symbol has been defined.
461 bool tls_base_symbol_defined_
;
464 const Target::Target_info
Target_i386::i386_info
=
467 false, // is_big_endian
468 elfcpp::EM_386
, // machine_code
469 false, // has_make_symbol
470 false, // has_resolve
471 true, // has_code_fill
472 true, // is_default_stack_executable
474 "/usr/lib/libc.so.1", // dynamic_linker
475 0x08048000, // default_text_segment_address
476 0x1000, // abi_pagesize (overridable by -z max-page-size)
477 0x1000, // common_pagesize (overridable by -z common-page-size)
478 elfcpp::SHN_UNDEF
, // small_common_shndx
479 elfcpp::SHN_UNDEF
, // large_common_shndx
480 0, // small_common_section_flags
481 0, // large_common_section_flags
482 NULL
, // attributes_section
483 NULL
// attributes_vendor
486 // Get the GOT section, creating it if necessary.
488 Output_data_got
<32, false>*
489 Target_i386::got_section(Symbol_table
* symtab
, Layout
* layout
)
491 if (this->got_
== NULL
)
493 gold_assert(symtab
!= NULL
&& layout
!= NULL
);
495 this->got_
= new Output_data_got
<32, false>();
498 os
= layout
->add_output_section_data(".got", elfcpp::SHT_PROGBITS
,
500 | elfcpp::SHF_WRITE
),
501 this->got_
, false, true, true,
504 this->got_plt_
= new Output_data_space(4, "** GOT PLT");
505 os
= layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
507 | elfcpp::SHF_WRITE
),
508 this->got_plt_
, false, false, false,
511 // The first three entries are reserved.
512 this->got_plt_
->set_current_data_size(3 * 4);
514 // Those bytes can go into the relro segment.
515 layout
->increase_relro(3 * 4);
517 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
518 this->global_offset_table_
=
519 symtab
->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL
,
520 Symbol_table::PREDEFINED
,
522 0, 0, elfcpp::STT_OBJECT
,
524 elfcpp::STV_HIDDEN
, 0,
531 // Get the dynamic reloc section, creating it if necessary.
533 Target_i386::Reloc_section
*
534 Target_i386::rel_dyn_section(Layout
* layout
)
536 if (this->rel_dyn_
== NULL
)
538 gold_assert(layout
!= NULL
);
539 this->rel_dyn_
= new Reloc_section(parameters
->options().combreloc());
540 layout
->add_output_section_data(".rel.dyn", elfcpp::SHT_REL
,
541 elfcpp::SHF_ALLOC
, this->rel_dyn_
, true,
542 false, false, false);
544 return this->rel_dyn_
;
547 // A class to handle the PLT data.
549 class Output_data_plt_i386
: public Output_section_data
552 typedef Output_data_reloc
<elfcpp::SHT_REL
, true, 32, false> Reloc_section
;
554 Output_data_plt_i386(Layout
*, Output_data_space
*);
556 // Add an entry to the PLT.
558 add_entry(Symbol
* gsym
);
560 // Return the .rel.plt section data.
563 { return this->rel_
; }
565 // Return where the TLS_DESC relocations should go.
567 rel_tls_desc(Layout
*);
571 do_adjust_output_section(Output_section
* os
);
573 // Write to a map file.
575 do_print_to_mapfile(Mapfile
* mapfile
) const
576 { mapfile
->print_output_data(this, _("** PLT")); }
579 // The size of an entry in the PLT.
580 static const int plt_entry_size
= 16;
582 // The first entry in the PLT for an executable.
583 static unsigned char exec_first_plt_entry
[plt_entry_size
];
585 // The first entry in the PLT for a shared object.
586 static unsigned char dyn_first_plt_entry
[plt_entry_size
];
588 // Other entries in the PLT for an executable.
589 static unsigned char exec_plt_entry
[plt_entry_size
];
591 // Other entries in the PLT for a shared object.
592 static unsigned char dyn_plt_entry
[plt_entry_size
];
594 // Set the final size.
596 set_final_data_size()
597 { this->set_data_size((this->count_
+ 1) * plt_entry_size
); }
599 // Write out the PLT data.
601 do_write(Output_file
*);
603 // The reloc section.
605 // The TLS_DESC relocations, if necessary. These must follow the
606 // regular PLT relocs.
607 Reloc_section
* tls_desc_rel_
;
608 // The .got.plt section.
609 Output_data_space
* got_plt_
;
610 // The number of PLT entries.
614 // Create the PLT section. The ordinary .got section is an argument,
615 // since we need to refer to the start. We also create our own .got
616 // section just for PLT entries.
618 Output_data_plt_i386::Output_data_plt_i386(Layout
* layout
,
619 Output_data_space
* got_plt
)
620 : Output_section_data(4), tls_desc_rel_(NULL
), got_plt_(got_plt
), count_(0)
622 this->rel_
= new Reloc_section(false);
623 layout
->add_output_section_data(".rel.plt", elfcpp::SHT_REL
,
624 elfcpp::SHF_ALLOC
, this->rel_
, true,
625 false, false, false);
629 Output_data_plt_i386::do_adjust_output_section(Output_section
* os
)
631 // UnixWare sets the entsize of .plt to 4, and so does the old GNU
632 // linker, and so do we.
636 // Add an entry to the PLT.
639 Output_data_plt_i386::add_entry(Symbol
* gsym
)
641 gold_assert(!gsym
->has_plt_offset());
643 // Note that when setting the PLT offset we skip the initial
644 // reserved PLT entry.
645 gsym
->set_plt_offset((this->count_
+ 1) * plt_entry_size
);
649 section_offset_type got_offset
= this->got_plt_
->current_data_size();
651 // Every PLT entry needs a GOT entry which points back to the PLT
652 // entry (this will be changed by the dynamic linker, normally
653 // lazily when the function is called).
654 this->got_plt_
->set_current_data_size(got_offset
+ 4);
656 // Every PLT entry needs a reloc.
657 gsym
->set_needs_dynsym_entry();
658 this->rel_
->add_global(gsym
, elfcpp::R_386_JUMP_SLOT
, this->got_plt_
,
661 // Note that we don't need to save the symbol. The contents of the
662 // PLT are independent of which symbols are used. The symbols only
663 // appear in the relocations.
666 // Return where the TLS_DESC relocations should go, creating it if
667 // necessary. These follow the JUMP_SLOT relocations.
669 Output_data_plt_i386::Reloc_section
*
670 Output_data_plt_i386::rel_tls_desc(Layout
* layout
)
672 if (this->tls_desc_rel_
== NULL
)
674 this->tls_desc_rel_
= new Reloc_section(false);
675 layout
->add_output_section_data(".rel.plt", elfcpp::SHT_REL
,
676 elfcpp::SHF_ALLOC
, this->tls_desc_rel_
,
677 true, false, false, false);
678 gold_assert(this->tls_desc_rel_
->output_section() ==
679 this->rel_
->output_section());
681 return this->tls_desc_rel_
;
684 // The first entry in the PLT for an executable.
686 unsigned char Output_data_plt_i386::exec_first_plt_entry
[plt_entry_size
] =
688 0xff, 0x35, // pushl contents of memory address
689 0, 0, 0, 0, // replaced with address of .got + 4
690 0xff, 0x25, // jmp indirect
691 0, 0, 0, 0, // replaced with address of .got + 8
695 // The first entry in the PLT for a shared object.
697 unsigned char Output_data_plt_i386::dyn_first_plt_entry
[plt_entry_size
] =
699 0xff, 0xb3, 4, 0, 0, 0, // pushl 4(%ebx)
700 0xff, 0xa3, 8, 0, 0, 0, // jmp *8(%ebx)
704 // Subsequent entries in the PLT for an executable.
706 unsigned char Output_data_plt_i386::exec_plt_entry
[plt_entry_size
] =
708 0xff, 0x25, // jmp indirect
709 0, 0, 0, 0, // replaced with address of symbol in .got
710 0x68, // pushl immediate
711 0, 0, 0, 0, // replaced with offset into relocation table
712 0xe9, // jmp relative
713 0, 0, 0, 0 // replaced with offset to start of .plt
716 // Subsequent entries in the PLT for a shared object.
718 unsigned char Output_data_plt_i386::dyn_plt_entry
[plt_entry_size
] =
720 0xff, 0xa3, // jmp *offset(%ebx)
721 0, 0, 0, 0, // replaced with offset of symbol in .got
722 0x68, // pushl immediate
723 0, 0, 0, 0, // replaced with offset into relocation table
724 0xe9, // jmp relative
725 0, 0, 0, 0 // replaced with offset to start of .plt
728 // Write out the PLT. This uses the hand-coded instructions above,
729 // and adjusts them as needed. This is all specified by the i386 ELF
730 // Processor Supplement.
733 Output_data_plt_i386::do_write(Output_file
* of
)
735 const off_t offset
= this->offset();
736 const section_size_type oview_size
=
737 convert_to_section_size_type(this->data_size());
738 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
740 const off_t got_file_offset
= this->got_plt_
->offset();
741 const section_size_type got_size
=
742 convert_to_section_size_type(this->got_plt_
->data_size());
743 unsigned char* const got_view
= of
->get_output_view(got_file_offset
,
746 unsigned char* pov
= oview
;
748 elfcpp::Elf_types
<32>::Elf_Addr plt_address
= this->address();
749 elfcpp::Elf_types
<32>::Elf_Addr got_address
= this->got_plt_
->address();
751 if (parameters
->options().output_is_position_independent())
752 memcpy(pov
, dyn_first_plt_entry
, plt_entry_size
);
755 memcpy(pov
, exec_first_plt_entry
, plt_entry_size
);
756 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2, got_address
+ 4);
757 elfcpp::Swap
<32, false>::writeval(pov
+ 8, got_address
+ 8);
759 pov
+= plt_entry_size
;
761 unsigned char* got_pov
= got_view
;
763 memset(got_pov
, 0, 12);
766 const int rel_size
= elfcpp::Elf_sizes
<32>::rel_size
;
768 unsigned int plt_offset
= plt_entry_size
;
769 unsigned int plt_rel_offset
= 0;
770 unsigned int got_offset
= 12;
771 const unsigned int count
= this->count_
;
772 for (unsigned int i
= 0;
775 pov
+= plt_entry_size
,
777 plt_offset
+= plt_entry_size
,
778 plt_rel_offset
+= rel_size
,
781 // Set and adjust the PLT entry itself.
783 if (parameters
->options().output_is_position_independent())
785 memcpy(pov
, dyn_plt_entry
, plt_entry_size
);
786 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2, got_offset
);
790 memcpy(pov
, exec_plt_entry
, plt_entry_size
);
791 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
796 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 7, plt_rel_offset
);
797 elfcpp::Swap
<32, false>::writeval(pov
+ 12,
798 - (plt_offset
+ plt_entry_size
));
800 // Set the entry in the GOT.
801 elfcpp::Swap
<32, false>::writeval(got_pov
, plt_address
+ plt_offset
+ 6);
804 gold_assert(static_cast<section_size_type
>(pov
- oview
) == oview_size
);
805 gold_assert(static_cast<section_size_type
>(got_pov
- got_view
) == got_size
);
807 of
->write_output_view(offset
, oview_size
, oview
);
808 of
->write_output_view(got_file_offset
, got_size
, got_view
);
811 // Create a PLT entry for a global symbol.
814 Target_i386::make_plt_entry(Symbol_table
* symtab
, Layout
* layout
, Symbol
* gsym
)
816 if (gsym
->has_plt_offset())
819 if (this->plt_
== NULL
)
821 // Create the GOT sections first.
822 this->got_section(symtab
, layout
);
824 this->plt_
= new Output_data_plt_i386(layout
, this->got_plt_
);
825 layout
->add_output_section_data(".plt", elfcpp::SHT_PROGBITS
,
827 | elfcpp::SHF_EXECINSTR
),
828 this->plt_
, false, false, false, false);
831 this->plt_
->add_entry(gsym
);
834 // Get the section to use for TLS_DESC relocations.
836 Target_i386::Reloc_section
*
837 Target_i386::rel_tls_desc_section(Layout
* layout
) const
839 return this->plt_section()->rel_tls_desc(layout
);
842 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
845 Target_i386::define_tls_base_symbol(Symbol_table
* symtab
, Layout
* layout
)
847 if (this->tls_base_symbol_defined_
)
850 Output_segment
* tls_segment
= layout
->tls_segment();
851 if (tls_segment
!= NULL
)
853 bool is_exec
= parameters
->options().output_is_executable();
854 symtab
->define_in_output_segment("_TLS_MODULE_BASE_", NULL
,
855 Symbol_table::PREDEFINED
,
859 elfcpp::STV_HIDDEN
, 0,
861 ? Symbol::SEGMENT_END
862 : Symbol::SEGMENT_START
),
865 this->tls_base_symbol_defined_
= true;
868 // Create a GOT entry for the TLS module index.
871 Target_i386::got_mod_index_entry(Symbol_table
* symtab
, Layout
* layout
,
872 Sized_relobj
<32, false>* object
)
874 if (this->got_mod_index_offset_
== -1U)
876 gold_assert(symtab
!= NULL
&& layout
!= NULL
&& object
!= NULL
);
877 Reloc_section
* rel_dyn
= this->rel_dyn_section(layout
);
878 Output_data_got
<32, false>* got
= this->got_section(symtab
, layout
);
879 unsigned int got_offset
= got
->add_constant(0);
880 rel_dyn
->add_local(object
, 0, elfcpp::R_386_TLS_DTPMOD32
, got
,
882 got
->add_constant(0);
883 this->got_mod_index_offset_
= got_offset
;
885 return this->got_mod_index_offset_
;
888 // Optimize the TLS relocation type based on what we know about the
889 // symbol. IS_FINAL is true if the final address of this symbol is
890 // known at link time.
892 tls::Tls_optimization
893 Target_i386::optimize_tls_reloc(bool is_final
, int r_type
)
895 // If we are generating a shared library, then we can't do anything
897 if (parameters
->options().shared())
898 return tls::TLSOPT_NONE
;
902 case elfcpp::R_386_TLS_GD
:
903 case elfcpp::R_386_TLS_GOTDESC
:
904 case elfcpp::R_386_TLS_DESC_CALL
:
905 // These are General-Dynamic which permits fully general TLS
906 // access. Since we know that we are generating an executable,
907 // we can convert this to Initial-Exec. If we also know that
908 // this is a local symbol, we can further switch to Local-Exec.
910 return tls::TLSOPT_TO_LE
;
911 return tls::TLSOPT_TO_IE
;
913 case elfcpp::R_386_TLS_LDM
:
914 // This is Local-Dynamic, which refers to a local symbol in the
915 // dynamic TLS block. Since we know that we generating an
916 // executable, we can switch to Local-Exec.
917 return tls::TLSOPT_TO_LE
;
919 case elfcpp::R_386_TLS_LDO_32
:
920 // Another type of Local-Dynamic relocation.
921 return tls::TLSOPT_TO_LE
;
923 case elfcpp::R_386_TLS_IE
:
924 case elfcpp::R_386_TLS_GOTIE
:
925 case elfcpp::R_386_TLS_IE_32
:
926 // These are Initial-Exec relocs which get the thread offset
927 // from the GOT. If we know that we are linking against the
928 // local symbol, we can switch to Local-Exec, which links the
929 // thread offset into the instruction.
931 return tls::TLSOPT_TO_LE
;
932 return tls::TLSOPT_NONE
;
934 case elfcpp::R_386_TLS_LE
:
935 case elfcpp::R_386_TLS_LE_32
:
936 // When we already have Local-Exec, there is nothing further we
938 return tls::TLSOPT_NONE
;
945 // Report an unsupported relocation against a local symbol.
948 Target_i386::Scan::unsupported_reloc_local(Sized_relobj
<32, false>* object
,
951 gold_error(_("%s: unsupported reloc %u against local symbol"),
952 object
->name().c_str(), r_type
);
955 // Scan a relocation for a local symbol.
958 Target_i386::Scan::local(Symbol_table
* symtab
,
961 Sized_relobj
<32, false>* object
,
962 unsigned int data_shndx
,
963 Output_section
* output_section
,
964 const elfcpp::Rel
<32, false>& reloc
,
966 const elfcpp::Sym
<32, false>& lsym
)
970 case elfcpp::R_386_NONE
:
971 case elfcpp::R_386_GNU_VTINHERIT
:
972 case elfcpp::R_386_GNU_VTENTRY
:
975 case elfcpp::R_386_32
:
976 // If building a shared library (or a position-independent
977 // executable), we need to create a dynamic relocation for
978 // this location. The relocation applied at link time will
979 // apply the link-time value, so we flag the location with
980 // an R_386_RELATIVE relocation so the dynamic loader can
981 // relocate it easily.
982 if (parameters
->options().output_is_position_independent())
984 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
985 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
986 rel_dyn
->add_local_relative(object
, r_sym
, elfcpp::R_386_RELATIVE
,
987 output_section
, data_shndx
,
988 reloc
.get_r_offset());
992 case elfcpp::R_386_16
:
993 case elfcpp::R_386_8
:
994 // If building a shared library (or a position-independent
995 // executable), we need to create a dynamic relocation for
996 // this location. Because the addend needs to remain in the
997 // data section, we need to be careful not to apply this
998 // relocation statically.
999 if (parameters
->options().output_is_position_independent())
1001 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1002 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1003 if (lsym
.get_st_type() != elfcpp::STT_SECTION
)
1004 rel_dyn
->add_local(object
, r_sym
, r_type
, output_section
,
1005 data_shndx
, reloc
.get_r_offset());
1008 gold_assert(lsym
.get_st_value() == 0);
1009 unsigned int shndx
= lsym
.get_st_shndx();
1011 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
,
1014 object
->error(_("section symbol %u has bad shndx %u"),
1017 rel_dyn
->add_local_section(object
, shndx
,
1018 r_type
, output_section
,
1019 data_shndx
, reloc
.get_r_offset());
1024 case elfcpp::R_386_PC32
:
1025 case elfcpp::R_386_PC16
:
1026 case elfcpp::R_386_PC8
:
1029 case elfcpp::R_386_PLT32
:
1030 // Since we know this is a local symbol, we can handle this as a
1034 case elfcpp::R_386_GOTOFF
:
1035 case elfcpp::R_386_GOTPC
:
1036 // We need a GOT section.
1037 target
->got_section(symtab
, layout
);
1040 case elfcpp::R_386_GOT32
:
1042 // The symbol requires a GOT entry.
1043 Output_data_got
<32, false>* got
= target
->got_section(symtab
, layout
);
1044 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1045 if (got
->add_local(object
, r_sym
, GOT_TYPE_STANDARD
))
1047 // If we are generating a shared object, we need to add a
1048 // dynamic RELATIVE relocation for this symbol's GOT entry.
1049 if (parameters
->options().output_is_position_independent())
1051 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1052 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1053 rel_dyn
->add_local_relative(
1054 object
, r_sym
, elfcpp::R_386_RELATIVE
, got
,
1055 object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
));
1061 // These are relocations which should only be seen by the
1062 // dynamic linker, and should never be seen here.
1063 case elfcpp::R_386_COPY
:
1064 case elfcpp::R_386_GLOB_DAT
:
1065 case elfcpp::R_386_JUMP_SLOT
:
1066 case elfcpp::R_386_RELATIVE
:
1067 case elfcpp::R_386_TLS_TPOFF
:
1068 case elfcpp::R_386_TLS_DTPMOD32
:
1069 case elfcpp::R_386_TLS_DTPOFF32
:
1070 case elfcpp::R_386_TLS_TPOFF32
:
1071 case elfcpp::R_386_TLS_DESC
:
1072 gold_error(_("%s: unexpected reloc %u in object file"),
1073 object
->name().c_str(), r_type
);
1076 // These are initial TLS relocs, which are expected when
1078 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1079 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
1080 case elfcpp::R_386_TLS_DESC_CALL
:
1081 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1082 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1083 case elfcpp::R_386_TLS_IE
: // Initial-exec
1084 case elfcpp::R_386_TLS_IE_32
:
1085 case elfcpp::R_386_TLS_GOTIE
:
1086 case elfcpp::R_386_TLS_LE
: // Local-exec
1087 case elfcpp::R_386_TLS_LE_32
:
1089 bool output_is_shared
= parameters
->options().shared();
1090 const tls::Tls_optimization optimized_type
1091 = Target_i386::optimize_tls_reloc(!output_is_shared
, r_type
);
1094 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1095 if (optimized_type
== tls::TLSOPT_NONE
)
1097 // Create a pair of GOT entries for the module index and
1098 // dtv-relative offset.
1099 Output_data_got
<32, false>* got
1100 = target
->got_section(symtab
, layout
);
1101 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1102 unsigned int shndx
= lsym
.get_st_shndx();
1104 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
, &is_ordinary
);
1106 object
->error(_("local symbol %u has bad shndx %u"),
1109 got
->add_local_pair_with_rel(object
, r_sym
, shndx
,
1111 target
->rel_dyn_section(layout
),
1112 elfcpp::R_386_TLS_DTPMOD32
, 0);
1114 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1115 unsupported_reloc_local(object
, r_type
);
1118 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva)
1119 target
->define_tls_base_symbol(symtab
, layout
);
1120 if (optimized_type
== tls::TLSOPT_NONE
)
1122 // Create a double GOT entry with an R_386_TLS_DESC reloc.
1123 Output_data_got
<32, false>* got
1124 = target
->got_section(symtab
, layout
);
1125 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1126 if (!object
->local_has_got_offset(r_sym
, GOT_TYPE_TLS_DESC
))
1128 unsigned int got_offset
= got
->add_constant(0);
1129 // The local symbol value is stored in the second
1131 got
->add_local(object
, r_sym
, GOT_TYPE_TLS_DESC
);
1132 // That set the GOT offset of the local symbol to
1133 // point to the second entry, but we want it to
1134 // point to the first.
1135 object
->set_local_got_offset(r_sym
, GOT_TYPE_TLS_DESC
,
1137 Reloc_section
* rt
= target
->rel_tls_desc_section(layout
);
1138 rt
->add_absolute(elfcpp::R_386_TLS_DESC
, got
, got_offset
);
1141 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1142 unsupported_reloc_local(object
, r_type
);
1145 case elfcpp::R_386_TLS_DESC_CALL
:
1148 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1149 if (optimized_type
== tls::TLSOPT_NONE
)
1151 // Create a GOT entry for the module index.
1152 target
->got_mod_index_entry(symtab
, layout
, object
);
1154 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1155 unsupported_reloc_local(object
, r_type
);
1158 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1161 case elfcpp::R_386_TLS_IE
: // Initial-exec
1162 case elfcpp::R_386_TLS_IE_32
:
1163 case elfcpp::R_386_TLS_GOTIE
:
1164 layout
->set_has_static_tls();
1165 if (optimized_type
== tls::TLSOPT_NONE
)
1167 // For the R_386_TLS_IE relocation, we need to create a
1168 // dynamic relocation when building a shared library.
1169 if (r_type
== elfcpp::R_386_TLS_IE
1170 && parameters
->options().shared())
1172 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1174 = elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1175 rel_dyn
->add_local_relative(object
, r_sym
,
1176 elfcpp::R_386_RELATIVE
,
1177 output_section
, data_shndx
,
1178 reloc
.get_r_offset());
1180 // Create a GOT entry for the tp-relative offset.
1181 Output_data_got
<32, false>* got
1182 = target
->got_section(symtab
, layout
);
1183 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1184 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_IE_32
1185 ? elfcpp::R_386_TLS_TPOFF32
1186 : elfcpp::R_386_TLS_TPOFF
);
1187 unsigned int got_type
= (r_type
== elfcpp::R_386_TLS_IE_32
1188 ? GOT_TYPE_TLS_OFFSET
1189 : GOT_TYPE_TLS_NOFFSET
);
1190 got
->add_local_with_rel(object
, r_sym
, got_type
,
1191 target
->rel_dyn_section(layout
),
1194 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1195 unsupported_reloc_local(object
, r_type
);
1198 case elfcpp::R_386_TLS_LE
: // Local-exec
1199 case elfcpp::R_386_TLS_LE_32
:
1200 layout
->set_has_static_tls();
1201 if (output_is_shared
)
1203 // We need to create a dynamic relocation.
1204 gold_assert(lsym
.get_st_type() != elfcpp::STT_SECTION
);
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_LE_32
1207 ? elfcpp::R_386_TLS_TPOFF32
1208 : elfcpp::R_386_TLS_TPOFF
);
1209 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1210 rel_dyn
->add_local(object
, r_sym
, dyn_r_type
, output_section
,
1211 data_shndx
, reloc
.get_r_offset());
1221 case elfcpp::R_386_32PLT
:
1222 case elfcpp::R_386_TLS_GD_32
:
1223 case elfcpp::R_386_TLS_GD_PUSH
:
1224 case elfcpp::R_386_TLS_GD_CALL
:
1225 case elfcpp::R_386_TLS_GD_POP
:
1226 case elfcpp::R_386_TLS_LDM_32
:
1227 case elfcpp::R_386_TLS_LDM_PUSH
:
1228 case elfcpp::R_386_TLS_LDM_CALL
:
1229 case elfcpp::R_386_TLS_LDM_POP
:
1230 case elfcpp::R_386_USED_BY_INTEL_200
:
1232 unsupported_reloc_local(object
, r_type
);
1237 // Report an unsupported relocation against a global symbol.
1240 Target_i386::Scan::unsupported_reloc_global(Sized_relobj
<32, false>* object
,
1241 unsigned int r_type
,
1244 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
1245 object
->name().c_str(), r_type
, gsym
->demangled_name().c_str());
1249 Target_i386::Scan::possible_function_pointer_reloc(unsigned int r_type
)
1253 case elfcpp::R_386_32
:
1254 case elfcpp::R_386_16
:
1255 case elfcpp::R_386_8
:
1256 case elfcpp::R_386_GOTOFF
:
1257 case elfcpp::R_386_GOT32
:
1268 Target_i386::Scan::local_reloc_may_be_function_pointer(
1272 Sized_relobj
<32, false>* ,
1275 const elfcpp::Rel
<32, false>& ,
1276 unsigned int r_type
,
1277 const elfcpp::Sym
<32, false>&)
1279 return possible_function_pointer_reloc(r_type
);
1283 Target_i386::Scan::global_reloc_may_be_function_pointer(
1287 Sized_relobj
<32, false>* ,
1290 const elfcpp::Rel
<32, false>& ,
1291 unsigned int r_type
,
1294 return possible_function_pointer_reloc(r_type
);
1297 // Scan a relocation for a global symbol.
1300 Target_i386::Scan::global(Symbol_table
* symtab
,
1302 Target_i386
* target
,
1303 Sized_relobj
<32, false>* object
,
1304 unsigned int data_shndx
,
1305 Output_section
* output_section
,
1306 const elfcpp::Rel
<32, false>& reloc
,
1307 unsigned int r_type
,
1312 case elfcpp::R_386_NONE
:
1313 case elfcpp::R_386_GNU_VTINHERIT
:
1314 case elfcpp::R_386_GNU_VTENTRY
:
1317 case elfcpp::R_386_32
:
1318 case elfcpp::R_386_16
:
1319 case elfcpp::R_386_8
:
1321 // Make a PLT entry if necessary.
1322 if (gsym
->needs_plt_entry())
1324 target
->make_plt_entry(symtab
, layout
, gsym
);
1325 // Since this is not a PC-relative relocation, we may be
1326 // taking the address of a function. In that case we need to
1327 // set the entry in the dynamic symbol table to the address of
1329 if (gsym
->is_from_dynobj() && !parameters
->options().shared())
1330 gsym
->set_needs_dynsym_value();
1332 // Make a dynamic relocation if necessary.
1333 if (gsym
->needs_dynamic_reloc(Symbol::ABSOLUTE_REF
))
1335 if (gsym
->may_need_copy_reloc())
1337 target
->copy_reloc(symtab
, layout
, object
,
1338 data_shndx
, output_section
, gsym
, reloc
);
1340 else if (r_type
== elfcpp::R_386_32
1341 && gsym
->can_use_relative_reloc(false))
1343 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1344 rel_dyn
->add_global_relative(gsym
, elfcpp::R_386_RELATIVE
,
1345 output_section
, object
,
1346 data_shndx
, reloc
.get_r_offset());
1350 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1351 rel_dyn
->add_global(gsym
, r_type
, output_section
, object
,
1352 data_shndx
, reloc
.get_r_offset());
1358 case elfcpp::R_386_PC32
:
1359 case elfcpp::R_386_PC16
:
1360 case elfcpp::R_386_PC8
:
1362 // Make a PLT entry if necessary.
1363 if (gsym
->needs_plt_entry())
1365 // These relocations are used for function calls only in
1366 // non-PIC code. For a 32-bit relocation in a shared library,
1367 // we'll need a text relocation anyway, so we can skip the
1368 // PLT entry and let the dynamic linker bind the call directly
1369 // to the target. For smaller relocations, we should use a
1370 // PLT entry to ensure that the call can reach.
1371 if (!parameters
->options().shared()
1372 || r_type
!= elfcpp::R_386_PC32
)
1373 target
->make_plt_entry(symtab
, layout
, gsym
);
1375 // Make a dynamic relocation if necessary.
1376 int flags
= Symbol::NON_PIC_REF
;
1377 if (gsym
->is_func())
1378 flags
|= Symbol::FUNCTION_CALL
;
1379 if (gsym
->needs_dynamic_reloc(flags
))
1381 if (gsym
->may_need_copy_reloc())
1383 target
->copy_reloc(symtab
, layout
, object
,
1384 data_shndx
, output_section
, gsym
, reloc
);
1388 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1389 rel_dyn
->add_global(gsym
, r_type
, output_section
, object
,
1390 data_shndx
, reloc
.get_r_offset());
1396 case elfcpp::R_386_GOT32
:
1398 // The symbol requires a GOT entry.
1399 Output_data_got
<32, false>* got
= target
->got_section(symtab
, layout
);
1400 if (gsym
->final_value_is_known())
1401 got
->add_global(gsym
, GOT_TYPE_STANDARD
);
1404 // If this symbol is not fully resolved, we need to add a
1405 // GOT entry with a dynamic relocation.
1406 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1407 if (gsym
->is_from_dynobj()
1408 || gsym
->is_undefined()
1409 || gsym
->is_preemptible())
1410 got
->add_global_with_rel(gsym
, GOT_TYPE_STANDARD
,
1411 rel_dyn
, elfcpp::R_386_GLOB_DAT
);
1414 if (got
->add_global(gsym
, GOT_TYPE_STANDARD
))
1415 rel_dyn
->add_global_relative(
1416 gsym
, elfcpp::R_386_RELATIVE
, got
,
1417 gsym
->got_offset(GOT_TYPE_STANDARD
));
1423 case elfcpp::R_386_PLT32
:
1424 // If the symbol is fully resolved, this is just a PC32 reloc.
1425 // Otherwise we need a PLT entry.
1426 if (gsym
->final_value_is_known())
1428 // If building a shared library, we can also skip the PLT entry
1429 // if the symbol is defined in the output file and is protected
1431 if (gsym
->is_defined()
1432 && !gsym
->is_from_dynobj()
1433 && !gsym
->is_preemptible())
1435 target
->make_plt_entry(symtab
, layout
, gsym
);
1438 case elfcpp::R_386_GOTOFF
:
1439 case elfcpp::R_386_GOTPC
:
1440 // We need a GOT section.
1441 target
->got_section(symtab
, layout
);
1444 // These are relocations which should only be seen by the
1445 // dynamic linker, and should never be seen here.
1446 case elfcpp::R_386_COPY
:
1447 case elfcpp::R_386_GLOB_DAT
:
1448 case elfcpp::R_386_JUMP_SLOT
:
1449 case elfcpp::R_386_RELATIVE
:
1450 case elfcpp::R_386_TLS_TPOFF
:
1451 case elfcpp::R_386_TLS_DTPMOD32
:
1452 case elfcpp::R_386_TLS_DTPOFF32
:
1453 case elfcpp::R_386_TLS_TPOFF32
:
1454 case elfcpp::R_386_TLS_DESC
:
1455 gold_error(_("%s: unexpected reloc %u in object file"),
1456 object
->name().c_str(), r_type
);
1459 // These are initial tls relocs, which are expected when
1461 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1462 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
1463 case elfcpp::R_386_TLS_DESC_CALL
:
1464 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1465 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1466 case elfcpp::R_386_TLS_IE
: // Initial-exec
1467 case elfcpp::R_386_TLS_IE_32
:
1468 case elfcpp::R_386_TLS_GOTIE
:
1469 case elfcpp::R_386_TLS_LE
: // Local-exec
1470 case elfcpp::R_386_TLS_LE_32
:
1472 const bool is_final
= gsym
->final_value_is_known();
1473 const tls::Tls_optimization optimized_type
1474 = Target_i386::optimize_tls_reloc(is_final
, r_type
);
1477 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1478 if (optimized_type
== tls::TLSOPT_NONE
)
1480 // Create a pair of GOT entries for the module index and
1481 // dtv-relative offset.
1482 Output_data_got
<32, false>* got
1483 = target
->got_section(symtab
, layout
);
1484 got
->add_global_pair_with_rel(gsym
, GOT_TYPE_TLS_PAIR
,
1485 target
->rel_dyn_section(layout
),
1486 elfcpp::R_386_TLS_DTPMOD32
,
1487 elfcpp::R_386_TLS_DTPOFF32
);
1489 else if (optimized_type
== tls::TLSOPT_TO_IE
)
1491 // Create a GOT entry for the tp-relative offset.
1492 Output_data_got
<32, false>* got
1493 = target
->got_section(symtab
, layout
);
1494 got
->add_global_with_rel(gsym
, GOT_TYPE_TLS_NOFFSET
,
1495 target
->rel_dyn_section(layout
),
1496 elfcpp::R_386_TLS_TPOFF
);
1498 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1499 unsupported_reloc_global(object
, r_type
, gsym
);
1502 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (~oliva url)
1503 target
->define_tls_base_symbol(symtab
, layout
);
1504 if (optimized_type
== tls::TLSOPT_NONE
)
1506 // Create a double GOT entry with an R_386_TLS_DESC reloc.
1507 Output_data_got
<32, false>* got
1508 = target
->got_section(symtab
, layout
);
1509 Reloc_section
* rt
= target
->rel_tls_desc_section(layout
);
1510 got
->add_global_pair_with_rel(gsym
, GOT_TYPE_TLS_DESC
, rt
,
1511 elfcpp::R_386_TLS_DESC
, 0);
1513 else if (optimized_type
== tls::TLSOPT_TO_IE
)
1515 // Create a GOT entry for the tp-relative offset.
1516 Output_data_got
<32, false>* got
1517 = target
->got_section(symtab
, layout
);
1518 got
->add_global_with_rel(gsym
, GOT_TYPE_TLS_NOFFSET
,
1519 target
->rel_dyn_section(layout
),
1520 elfcpp::R_386_TLS_TPOFF
);
1522 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1523 unsupported_reloc_global(object
, r_type
, gsym
);
1526 case elfcpp::R_386_TLS_DESC_CALL
:
1529 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1530 if (optimized_type
== tls::TLSOPT_NONE
)
1532 // Create a GOT entry for the module index.
1533 target
->got_mod_index_entry(symtab
, layout
, object
);
1535 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1536 unsupported_reloc_global(object
, r_type
, gsym
);
1539 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1542 case elfcpp::R_386_TLS_IE
: // Initial-exec
1543 case elfcpp::R_386_TLS_IE_32
:
1544 case elfcpp::R_386_TLS_GOTIE
:
1545 layout
->set_has_static_tls();
1546 if (optimized_type
== tls::TLSOPT_NONE
)
1548 // For the R_386_TLS_IE relocation, we need to create a
1549 // dynamic relocation when building a shared library.
1550 if (r_type
== elfcpp::R_386_TLS_IE
1551 && parameters
->options().shared())
1553 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1554 rel_dyn
->add_global_relative(gsym
, elfcpp::R_386_RELATIVE
,
1555 output_section
, object
,
1557 reloc
.get_r_offset());
1559 // Create a GOT entry for the tp-relative offset.
1560 Output_data_got
<32, false>* got
1561 = target
->got_section(symtab
, layout
);
1562 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_IE_32
1563 ? elfcpp::R_386_TLS_TPOFF32
1564 : elfcpp::R_386_TLS_TPOFF
);
1565 unsigned int got_type
= (r_type
== elfcpp::R_386_TLS_IE_32
1566 ? GOT_TYPE_TLS_OFFSET
1567 : GOT_TYPE_TLS_NOFFSET
);
1568 got
->add_global_with_rel(gsym
, got_type
,
1569 target
->rel_dyn_section(layout
),
1572 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1573 unsupported_reloc_global(object
, r_type
, gsym
);
1576 case elfcpp::R_386_TLS_LE
: // Local-exec
1577 case elfcpp::R_386_TLS_LE_32
:
1578 layout
->set_has_static_tls();
1579 if (parameters
->options().shared())
1581 // We need to create a dynamic relocation.
1582 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_LE_32
1583 ? elfcpp::R_386_TLS_TPOFF32
1584 : elfcpp::R_386_TLS_TPOFF
);
1585 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1586 rel_dyn
->add_global(gsym
, dyn_r_type
, output_section
, object
,
1587 data_shndx
, reloc
.get_r_offset());
1597 case elfcpp::R_386_32PLT
:
1598 case elfcpp::R_386_TLS_GD_32
:
1599 case elfcpp::R_386_TLS_GD_PUSH
:
1600 case elfcpp::R_386_TLS_GD_CALL
:
1601 case elfcpp::R_386_TLS_GD_POP
:
1602 case elfcpp::R_386_TLS_LDM_32
:
1603 case elfcpp::R_386_TLS_LDM_PUSH
:
1604 case elfcpp::R_386_TLS_LDM_CALL
:
1605 case elfcpp::R_386_TLS_LDM_POP
:
1606 case elfcpp::R_386_USED_BY_INTEL_200
:
1608 unsupported_reloc_global(object
, r_type
, gsym
);
1613 // Process relocations for gc.
1616 Target_i386::gc_process_relocs(Symbol_table
* symtab
,
1618 Sized_relobj
<32, false>* object
,
1619 unsigned int data_shndx
,
1621 const unsigned char* prelocs
,
1623 Output_section
* output_section
,
1624 bool needs_special_offset_handling
,
1625 size_t local_symbol_count
,
1626 const unsigned char* plocal_symbols
)
1628 gold::gc_process_relocs
<32, false, Target_i386
, elfcpp::SHT_REL
,
1638 needs_special_offset_handling
,
1643 // Scan relocations for a section.
1646 Target_i386::scan_relocs(Symbol_table
* symtab
,
1648 Sized_relobj
<32, false>* object
,
1649 unsigned int data_shndx
,
1650 unsigned int sh_type
,
1651 const unsigned char* prelocs
,
1653 Output_section
* output_section
,
1654 bool needs_special_offset_handling
,
1655 size_t local_symbol_count
,
1656 const unsigned char* plocal_symbols
)
1658 if (sh_type
== elfcpp::SHT_RELA
)
1660 gold_error(_("%s: unsupported RELA reloc section"),
1661 object
->name().c_str());
1665 gold::scan_relocs
<32, false, Target_i386
, elfcpp::SHT_REL
,
1675 needs_special_offset_handling
,
1680 // Finalize the sections.
1683 Target_i386::do_finalize_sections(
1685 const Input_objects
*,
1686 Symbol_table
* symtab
)
1688 const Reloc_section
* rel_plt
= (this->plt_
== NULL
1690 : this->plt_
->rel_plt());
1691 layout
->add_target_dynamic_tags(true, this->got_plt_
, rel_plt
,
1692 this->rel_dyn_
, true, false);
1694 // Emit any relocs we saved in an attempt to avoid generating COPY
1696 if (this->copy_relocs_
.any_saved_relocs())
1697 this->copy_relocs_
.emit(this->rel_dyn_section(layout
));
1699 // Set the size of the _GLOBAL_OFFSET_TABLE_ symbol to the size of
1700 // the .got.plt section.
1701 Symbol
* sym
= this->global_offset_table_
;
1704 uint32_t data_size
= this->got_plt_
->current_data_size();
1705 symtab
->get_sized_symbol
<32>(sym
)->set_symsize(data_size
);
1709 // Return whether a direct absolute static relocation needs to be applied.
1710 // In cases where Scan::local() or Scan::global() has created
1711 // a dynamic relocation other than R_386_RELATIVE, the addend
1712 // of the relocation is carried in the data, and we must not
1713 // apply the static relocation.
1716 Target_i386::Relocate::should_apply_static_reloc(const Sized_symbol
<32>* gsym
,
1719 Output_section
* output_section
)
1721 // If the output section is not allocated, then we didn't call
1722 // scan_relocs, we didn't create a dynamic reloc, and we must apply
1724 if ((output_section
->flags() & elfcpp::SHF_ALLOC
) == 0)
1727 // For local symbols, we will have created a non-RELATIVE dynamic
1728 // relocation only if (a) the output is position independent,
1729 // (b) the relocation is absolute (not pc- or segment-relative), and
1730 // (c) the relocation is not 32 bits wide.
1732 return !(parameters
->options().output_is_position_independent()
1733 && (ref_flags
& Symbol::ABSOLUTE_REF
)
1736 // For global symbols, we use the same helper routines used in the
1737 // scan pass. If we did not create a dynamic relocation, or if we
1738 // created a RELATIVE dynamic relocation, we should apply the static
1740 bool has_dyn
= gsym
->needs_dynamic_reloc(ref_flags
);
1741 bool is_rel
= (ref_flags
& Symbol::ABSOLUTE_REF
)
1742 && gsym
->can_use_relative_reloc(ref_flags
1743 & Symbol::FUNCTION_CALL
);
1744 return !has_dyn
|| is_rel
;
1747 // Perform a relocation.
1750 Target_i386::Relocate::relocate(const Relocate_info
<32, false>* relinfo
,
1751 Target_i386
* target
,
1752 Output_section
*output_section
,
1754 const elfcpp::Rel
<32, false>& rel
,
1755 unsigned int r_type
,
1756 const Sized_symbol
<32>* gsym
,
1757 const Symbol_value
<32>* psymval
,
1758 unsigned char* view
,
1759 elfcpp::Elf_types
<32>::Elf_Addr address
,
1760 section_size_type view_size
)
1762 if (this->skip_call_tls_get_addr_
)
1764 if ((r_type
!= elfcpp::R_386_PLT32
1765 && r_type
!= elfcpp::R_386_PC32
)
1767 || strcmp(gsym
->name(), "___tls_get_addr") != 0)
1768 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
1769 _("missing expected TLS relocation"));
1772 this->skip_call_tls_get_addr_
= false;
1777 // Pick the value to use for symbols defined in shared objects.
1778 Symbol_value
<32> symval
;
1780 && gsym
->use_plt_offset(r_type
== elfcpp::R_386_PC8
1781 || r_type
== elfcpp::R_386_PC16
1782 || r_type
== elfcpp::R_386_PC32
))
1784 symval
.set_output_value(target
->plt_section()->address()
1785 + gsym
->plt_offset());
1789 const Sized_relobj
<32, false>* object
= relinfo
->object
;
1791 // Get the GOT offset if needed.
1792 // The GOT pointer points to the end of the GOT section.
1793 // We need to subtract the size of the GOT section to get
1794 // the actual offset to use in the relocation.
1795 bool have_got_offset
= false;
1796 unsigned int got_offset
= 0;
1799 case elfcpp::R_386_GOT32
:
1802 gold_assert(gsym
->has_got_offset(GOT_TYPE_STANDARD
));
1803 got_offset
= (gsym
->got_offset(GOT_TYPE_STANDARD
)
1804 - target
->got_size());
1808 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
1809 gold_assert(object
->local_has_got_offset(r_sym
, GOT_TYPE_STANDARD
));
1810 got_offset
= (object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
)
1811 - target
->got_size());
1813 have_got_offset
= true;
1822 case elfcpp::R_386_NONE
:
1823 case elfcpp::R_386_GNU_VTINHERIT
:
1824 case elfcpp::R_386_GNU_VTENTRY
:
1827 case elfcpp::R_386_32
:
1828 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, true,
1830 Relocate_functions
<32, false>::rel32(view
, object
, psymval
);
1833 case elfcpp::R_386_PC32
:
1835 int ref_flags
= Symbol::NON_PIC_REF
;
1836 if (gsym
!= NULL
&& gsym
->is_func())
1837 ref_flags
|= Symbol::FUNCTION_CALL
;
1838 if (should_apply_static_reloc(gsym
, ref_flags
, true, output_section
))
1839 Relocate_functions
<32, false>::pcrel32(view
, object
, psymval
, address
);
1843 case elfcpp::R_386_16
:
1844 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, false,
1846 Relocate_functions
<32, false>::rel16(view
, object
, psymval
);
1849 case elfcpp::R_386_PC16
:
1851 int ref_flags
= Symbol::NON_PIC_REF
;
1852 if (gsym
!= NULL
&& gsym
->is_func())
1853 ref_flags
|= Symbol::FUNCTION_CALL
;
1854 if (should_apply_static_reloc(gsym
, ref_flags
, false, output_section
))
1855 Relocate_functions
<32, false>::pcrel16(view
, object
, psymval
, address
);
1859 case elfcpp::R_386_8
:
1860 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, false,
1862 Relocate_functions
<32, false>::rel8(view
, object
, psymval
);
1865 case elfcpp::R_386_PC8
:
1867 int ref_flags
= Symbol::NON_PIC_REF
;
1868 if (gsym
!= NULL
&& gsym
->is_func())
1869 ref_flags
|= Symbol::FUNCTION_CALL
;
1870 if (should_apply_static_reloc(gsym
, ref_flags
, false,
1872 Relocate_functions
<32, false>::pcrel8(view
, object
, psymval
, address
);
1876 case elfcpp::R_386_PLT32
:
1877 gold_assert(gsym
== NULL
1878 || gsym
->has_plt_offset()
1879 || gsym
->final_value_is_known()
1880 || (gsym
->is_defined()
1881 && !gsym
->is_from_dynobj()
1882 && !gsym
->is_preemptible()));
1883 Relocate_functions
<32, false>::pcrel32(view
, object
, psymval
, address
);
1886 case elfcpp::R_386_GOT32
:
1887 gold_assert(have_got_offset
);
1888 Relocate_functions
<32, false>::rel32(view
, got_offset
);
1891 case elfcpp::R_386_GOTOFF
:
1893 elfcpp::Elf_types
<32>::Elf_Addr value
;
1894 value
= (psymval
->value(object
, 0)
1895 - target
->got_plt_section()->address());
1896 Relocate_functions
<32, false>::rel32(view
, value
);
1900 case elfcpp::R_386_GOTPC
:
1902 elfcpp::Elf_types
<32>::Elf_Addr value
;
1903 value
= target
->got_plt_section()->address();
1904 Relocate_functions
<32, false>::pcrel32(view
, value
, address
);
1908 case elfcpp::R_386_COPY
:
1909 case elfcpp::R_386_GLOB_DAT
:
1910 case elfcpp::R_386_JUMP_SLOT
:
1911 case elfcpp::R_386_RELATIVE
:
1912 // These are outstanding tls relocs, which are unexpected when
1914 case elfcpp::R_386_TLS_TPOFF
:
1915 case elfcpp::R_386_TLS_DTPMOD32
:
1916 case elfcpp::R_386_TLS_DTPOFF32
:
1917 case elfcpp::R_386_TLS_TPOFF32
:
1918 case elfcpp::R_386_TLS_DESC
:
1919 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
1920 _("unexpected reloc %u in object file"),
1924 // These are initial tls relocs, which are expected when
1926 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1927 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
1928 case elfcpp::R_386_TLS_DESC_CALL
:
1929 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1930 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1931 case elfcpp::R_386_TLS_IE
: // Initial-exec
1932 case elfcpp::R_386_TLS_IE_32
:
1933 case elfcpp::R_386_TLS_GOTIE
:
1934 case elfcpp::R_386_TLS_LE
: // Local-exec
1935 case elfcpp::R_386_TLS_LE_32
:
1936 this->relocate_tls(relinfo
, target
, relnum
, rel
, r_type
, gsym
, psymval
,
1937 view
, address
, view_size
);
1940 case elfcpp::R_386_32PLT
:
1941 case elfcpp::R_386_TLS_GD_32
:
1942 case elfcpp::R_386_TLS_GD_PUSH
:
1943 case elfcpp::R_386_TLS_GD_CALL
:
1944 case elfcpp::R_386_TLS_GD_POP
:
1945 case elfcpp::R_386_TLS_LDM_32
:
1946 case elfcpp::R_386_TLS_LDM_PUSH
:
1947 case elfcpp::R_386_TLS_LDM_CALL
:
1948 case elfcpp::R_386_TLS_LDM_POP
:
1949 case elfcpp::R_386_USED_BY_INTEL_200
:
1951 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
1952 _("unsupported reloc %u"),
1960 // Perform a TLS relocation.
1963 Target_i386::Relocate::relocate_tls(const Relocate_info
<32, false>* relinfo
,
1964 Target_i386
* target
,
1966 const elfcpp::Rel
<32, false>& rel
,
1967 unsigned int r_type
,
1968 const Sized_symbol
<32>* gsym
,
1969 const Symbol_value
<32>* psymval
,
1970 unsigned char* view
,
1971 elfcpp::Elf_types
<32>::Elf_Addr
,
1972 section_size_type view_size
)
1974 Output_segment
* tls_segment
= relinfo
->layout
->tls_segment();
1976 const Sized_relobj
<32, false>* object
= relinfo
->object
;
1978 elfcpp::Elf_types
<32>::Elf_Addr value
= psymval
->value(object
, 0);
1980 const bool is_final
= (gsym
== NULL
1981 ? !parameters
->options().shared()
1982 : gsym
->final_value_is_known());
1983 const tls::Tls_optimization optimized_type
1984 = Target_i386::optimize_tls_reloc(is_final
, r_type
);
1987 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1988 if (optimized_type
== tls::TLSOPT_TO_LE
)
1990 gold_assert(tls_segment
!= NULL
);
1991 this->tls_gd_to_le(relinfo
, relnum
, tls_segment
,
1992 rel
, r_type
, value
, view
,
1998 unsigned int got_type
= (optimized_type
== tls::TLSOPT_TO_IE
1999 ? GOT_TYPE_TLS_NOFFSET
2000 : GOT_TYPE_TLS_PAIR
);
2001 unsigned int got_offset
;
2004 gold_assert(gsym
->has_got_offset(got_type
));
2005 got_offset
= gsym
->got_offset(got_type
) - target
->got_size();
2009 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
2010 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
2011 got_offset
= (object
->local_got_offset(r_sym
, got_type
)
2012 - target
->got_size());
2014 if (optimized_type
== tls::TLSOPT_TO_IE
)
2016 gold_assert(tls_segment
!= NULL
);
2017 this->tls_gd_to_ie(relinfo
, relnum
, tls_segment
, rel
, r_type
,
2018 got_offset
, view
, view_size
);
2021 else if (optimized_type
== tls::TLSOPT_NONE
)
2023 // Relocate the field with the offset of the pair of GOT
2025 Relocate_functions
<32, false>::rel32(view
, got_offset
);
2029 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2030 _("unsupported reloc %u"),
2034 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
2035 case elfcpp::R_386_TLS_DESC_CALL
:
2036 this->local_dynamic_type_
= LOCAL_DYNAMIC_GNU
;
2037 if (optimized_type
== tls::TLSOPT_TO_LE
)
2039 gold_assert(tls_segment
!= NULL
);
2040 this->tls_desc_gd_to_le(relinfo
, relnum
, tls_segment
,
2041 rel
, r_type
, value
, view
,
2047 unsigned int got_type
= (optimized_type
== tls::TLSOPT_TO_IE
2048 ? GOT_TYPE_TLS_NOFFSET
2049 : GOT_TYPE_TLS_DESC
);
2050 unsigned int got_offset
;
2053 gold_assert(gsym
->has_got_offset(got_type
));
2054 got_offset
= gsym
->got_offset(got_type
) - target
->got_size();
2058 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
2059 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
2060 got_offset
= (object
->local_got_offset(r_sym
, got_type
)
2061 - target
->got_size());
2063 if (optimized_type
== tls::TLSOPT_TO_IE
)
2065 gold_assert(tls_segment
!= NULL
);
2066 this->tls_desc_gd_to_ie(relinfo
, relnum
, tls_segment
, rel
, r_type
,
2067 got_offset
, view
, view_size
);
2070 else if (optimized_type
== tls::TLSOPT_NONE
)
2072 if (r_type
== elfcpp::R_386_TLS_GOTDESC
)
2074 // Relocate the field with the offset of the pair of GOT
2076 Relocate_functions
<32, false>::rel32(view
, got_offset
);
2081 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2082 _("unsupported reloc %u"),
2086 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
2087 if (this->local_dynamic_type_
== LOCAL_DYNAMIC_SUN
)
2089 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2090 _("both SUN and GNU model "
2091 "TLS relocations"));
2094 this->local_dynamic_type_
= LOCAL_DYNAMIC_GNU
;
2095 if (optimized_type
== tls::TLSOPT_TO_LE
)
2097 gold_assert(tls_segment
!= NULL
);
2098 this->tls_ld_to_le(relinfo
, relnum
, tls_segment
, rel
, r_type
,
2099 value
, view
, view_size
);
2102 else if (optimized_type
== tls::TLSOPT_NONE
)
2104 // Relocate the field with the offset of the GOT entry for
2105 // the module index.
2106 unsigned int got_offset
;
2107 got_offset
= (target
->got_mod_index_entry(NULL
, NULL
, NULL
)
2108 - target
->got_size());
2109 Relocate_functions
<32, false>::rel32(view
, got_offset
);
2112 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2113 _("unsupported reloc %u"),
2117 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
2118 if (optimized_type
== tls::TLSOPT_TO_LE
)
2120 // This reloc can appear in debugging sections, in which
2121 // case we must not convert to local-exec. We decide what
2122 // to do based on whether the section is marked as
2123 // containing executable code. That is what the GNU linker
2125 elfcpp::Shdr
<32, false> shdr(relinfo
->data_shdr
);
2126 if ((shdr
.get_sh_flags() & elfcpp::SHF_EXECINSTR
) != 0)
2128 gold_assert(tls_segment
!= NULL
);
2129 value
-= tls_segment
->memsz();
2132 Relocate_functions
<32, false>::rel32(view
, value
);
2135 case elfcpp::R_386_TLS_IE
: // Initial-exec
2136 case elfcpp::R_386_TLS_GOTIE
:
2137 case elfcpp::R_386_TLS_IE_32
:
2138 if (optimized_type
== tls::TLSOPT_TO_LE
)
2140 gold_assert(tls_segment
!= NULL
);
2141 Target_i386::Relocate::tls_ie_to_le(relinfo
, relnum
, tls_segment
,
2142 rel
, r_type
, value
, view
,
2146 else if (optimized_type
== tls::TLSOPT_NONE
)
2148 // Relocate the field with the offset of the GOT entry for
2149 // the tp-relative offset of the symbol.
2150 unsigned int got_type
= (r_type
== elfcpp::R_386_TLS_IE_32
2151 ? GOT_TYPE_TLS_OFFSET
2152 : GOT_TYPE_TLS_NOFFSET
);
2153 unsigned int got_offset
;
2156 gold_assert(gsym
->has_got_offset(got_type
));
2157 got_offset
= gsym
->got_offset(got_type
);
2161 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
2162 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
2163 got_offset
= object
->local_got_offset(r_sym
, got_type
);
2165 // For the R_386_TLS_IE relocation, we need to apply the
2166 // absolute address of the GOT entry.
2167 if (r_type
== elfcpp::R_386_TLS_IE
)
2168 got_offset
+= target
->got_plt_section()->address();
2169 // All GOT offsets are relative to the end of the GOT.
2170 got_offset
-= target
->got_size();
2171 Relocate_functions
<32, false>::rel32(view
, got_offset
);
2174 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2175 _("unsupported reloc %u"),
2179 case elfcpp::R_386_TLS_LE
: // Local-exec
2180 // If we're creating a shared library, a dynamic relocation will
2181 // have been created for this location, so do not apply it now.
2182 if (!parameters
->options().shared())
2184 gold_assert(tls_segment
!= NULL
);
2185 value
-= tls_segment
->memsz();
2186 Relocate_functions
<32, false>::rel32(view
, value
);
2190 case elfcpp::R_386_TLS_LE_32
:
2191 // If we're creating a shared library, a dynamic relocation will
2192 // have been created for this location, so do not apply it now.
2193 if (!parameters
->options().shared())
2195 gold_assert(tls_segment
!= NULL
);
2196 value
= tls_segment
->memsz() - value
;
2197 Relocate_functions
<32, false>::rel32(view
, value
);
2203 // Do a relocation in which we convert a TLS General-Dynamic to a
2207 Target_i386::Relocate::tls_gd_to_le(const Relocate_info
<32, false>* relinfo
,
2209 Output_segment
* tls_segment
,
2210 const elfcpp::Rel
<32, false>& rel
,
2212 elfcpp::Elf_types
<32>::Elf_Addr value
,
2213 unsigned char* view
,
2214 section_size_type view_size
)
2216 // leal foo(,%reg,1),%eax; call ___tls_get_addr
2217 // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
2218 // leal foo(%reg),%eax; call ___tls_get_addr
2219 // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
2221 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2222 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 9);
2224 unsigned char op1
= view
[-1];
2225 unsigned char op2
= view
[-2];
2227 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2228 op2
== 0x8d || op2
== 0x04);
2229 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[4] == 0xe8);
2235 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -3);
2236 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[-3] == 0x8d);
2237 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2238 ((op1
& 0xc7) == 0x05 && op1
!= (4 << 3)));
2239 memcpy(view
- 3, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
2243 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2244 (op1
& 0xf8) == 0x80 && (op1
& 7) != 4);
2245 if (rel
.get_r_offset() + 9 < view_size
2248 // There is a trailing nop. Use the size byte subl.
2249 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
2254 // Use the five byte subl.
2255 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
2259 value
= tls_segment
->memsz() - value
;
2260 Relocate_functions
<32, false>::rel32(view
+ roff
, value
);
2262 // The next reloc should be a PLT32 reloc against __tls_get_addr.
2264 this->skip_call_tls_get_addr_
= true;
2267 // Do a relocation in which we convert a TLS General-Dynamic to an
2271 Target_i386::Relocate::tls_gd_to_ie(const Relocate_info
<32, false>* relinfo
,
2274 const elfcpp::Rel
<32, false>& rel
,
2276 elfcpp::Elf_types
<32>::Elf_Addr value
,
2277 unsigned char* view
,
2278 section_size_type view_size
)
2280 // leal foo(,%ebx,1),%eax; call ___tls_get_addr
2281 // ==> movl %gs:0,%eax; addl foo@gotntpoff(%ebx),%eax
2283 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2284 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 9);
2286 unsigned char op1
= view
[-1];
2287 unsigned char op2
= view
[-2];
2289 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2290 op2
== 0x8d || op2
== 0x04);
2291 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[4] == 0xe8);
2295 // FIXME: For now, support only the first (SIB) form.
2296 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), op2
== 0x04);
2300 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -3);
2301 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[-3] == 0x8d);
2302 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2303 ((op1
& 0xc7) == 0x05 && op1
!= (4 << 3)));
2304 memcpy(view
- 3, "\x65\xa1\0\0\0\0\x03\x83\0\0\0", 12);
2308 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2309 (op1
& 0xf8) == 0x80 && (op1
& 7) != 4);
2310 if (rel
.get_r_offset() + 9 < view_size
2313 // FIXME: This is not the right instruction sequence.
2314 // There is a trailing nop. Use the size byte subl.
2315 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
2320 // FIXME: This is not the right instruction sequence.
2321 // Use the five byte subl.
2322 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
2326 Relocate_functions
<32, false>::rel32(view
+ roff
, value
);
2328 // The next reloc should be a PLT32 reloc against __tls_get_addr.
2330 this->skip_call_tls_get_addr_
= true;
2333 // Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL
2334 // General-Dynamic to a Local-Exec.
2337 Target_i386::Relocate::tls_desc_gd_to_le(
2338 const Relocate_info
<32, false>* relinfo
,
2340 Output_segment
* tls_segment
,
2341 const elfcpp::Rel
<32, false>& rel
,
2342 unsigned int r_type
,
2343 elfcpp::Elf_types
<32>::Elf_Addr value
,
2344 unsigned char* view
,
2345 section_size_type view_size
)
2347 if (r_type
== elfcpp::R_386_TLS_GOTDESC
)
2349 // leal foo@TLSDESC(%ebx), %eax
2350 // ==> leal foo@NTPOFF, %eax
2351 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2352 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
2353 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2354 view
[-2] == 0x8d && view
[-1] == 0x83);
2356 value
-= tls_segment
->memsz();
2357 Relocate_functions
<32, false>::rel32(view
, value
);
2361 // call *foo@TLSCALL(%eax)
2363 gold_assert(r_type
== elfcpp::R_386_TLS_DESC_CALL
);
2364 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 2);
2365 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2366 view
[0] == 0xff && view
[1] == 0x10);
2372 // Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL
2373 // General-Dynamic to an Initial-Exec.
2376 Target_i386::Relocate::tls_desc_gd_to_ie(
2377 const Relocate_info
<32, false>* relinfo
,
2380 const elfcpp::Rel
<32, false>& rel
,
2381 unsigned int r_type
,
2382 elfcpp::Elf_types
<32>::Elf_Addr value
,
2383 unsigned char* view
,
2384 section_size_type view_size
)
2386 if (r_type
== elfcpp::R_386_TLS_GOTDESC
)
2388 // leal foo@TLSDESC(%ebx), %eax
2389 // ==> movl foo@GOTNTPOFF(%ebx), %eax
2390 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2391 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
2392 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2393 view
[-2] == 0x8d && view
[-1] == 0x83);
2395 Relocate_functions
<32, false>::rel32(view
, value
);
2399 // call *foo@TLSCALL(%eax)
2401 gold_assert(r_type
== elfcpp::R_386_TLS_DESC_CALL
);
2402 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 2);
2403 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2404 view
[0] == 0xff && view
[1] == 0x10);
2410 // Do a relocation in which we convert a TLS Local-Dynamic to a
2414 Target_i386::Relocate::tls_ld_to_le(const Relocate_info
<32, false>* relinfo
,
2417 const elfcpp::Rel
<32, false>& rel
,
2419 elfcpp::Elf_types
<32>::Elf_Addr
,
2420 unsigned char* view
,
2421 section_size_type view_size
)
2423 // leal foo(%reg), %eax; call ___tls_get_addr
2424 // ==> movl %gs:0,%eax; nop; leal 0(%esi,1),%esi
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
, 9);
2429 // FIXME: Does this test really always pass?
2430 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2431 view
[-2] == 0x8d && view
[-1] == 0x83);
2433 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[4] == 0xe8);
2435 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x90\x8d\x74\x26\0", 11);
2437 // The next reloc should be a PLT32 reloc against __tls_get_addr.
2439 this->skip_call_tls_get_addr_
= true;
2442 // Do a relocation in which we convert a TLS Initial-Exec to a
2446 Target_i386::Relocate::tls_ie_to_le(const Relocate_info
<32, false>* relinfo
,
2448 Output_segment
* tls_segment
,
2449 const elfcpp::Rel
<32, false>& rel
,
2450 unsigned int r_type
,
2451 elfcpp::Elf_types
<32>::Elf_Addr value
,
2452 unsigned char* view
,
2453 section_size_type view_size
)
2455 // We have to actually change the instructions, which means that we
2456 // need to examine the opcodes to figure out which instruction we
2458 if (r_type
== elfcpp::R_386_TLS_IE
)
2460 // movl %gs:XX,%eax ==> movl $YY,%eax
2461 // movl %gs:XX,%reg ==> movl $YY,%reg
2462 // addl %gs:XX,%reg ==> addl $YY,%reg
2463 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -1);
2464 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
2466 unsigned char op1
= view
[-1];
2469 // movl XX,%eax ==> movl $YY,%eax
2474 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2476 unsigned char op2
= view
[-2];
2479 // movl XX,%reg ==> movl $YY,%reg
2480 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2481 (op1
& 0xc7) == 0x05);
2483 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
2485 else if (op2
== 0x03)
2487 // addl XX,%reg ==> addl $YY,%reg
2488 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2489 (op1
& 0xc7) == 0x05);
2491 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
2494 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), 0);
2499 // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2
2500 // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2
2501 // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2
2502 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2503 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
2505 unsigned char op1
= view
[-1];
2506 unsigned char op2
= view
[-2];
2507 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2508 (op1
& 0xc0) == 0x80 && (op1
& 7) != 4);
2511 // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2
2513 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
2515 else if (op2
== 0x2b)
2517 // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2
2519 view
[-1] = 0xe8 | ((op1
>> 3) & 7);
2521 else if (op2
== 0x03)
2523 // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2
2525 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
2528 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), 0);
2531 value
= tls_segment
->memsz() - value
;
2532 if (r_type
== elfcpp::R_386_TLS_IE
|| r_type
== elfcpp::R_386_TLS_GOTIE
)
2535 Relocate_functions
<32, false>::rel32(view
, value
);
2538 // Relocate section data.
2541 Target_i386::relocate_section(const Relocate_info
<32, false>* relinfo
,
2542 unsigned int sh_type
,
2543 const unsigned char* prelocs
,
2545 Output_section
* output_section
,
2546 bool needs_special_offset_handling
,
2547 unsigned char* view
,
2548 elfcpp::Elf_types
<32>::Elf_Addr address
,
2549 section_size_type view_size
,
2550 const Reloc_symbol_changes
* reloc_symbol_changes
)
2552 gold_assert(sh_type
== elfcpp::SHT_REL
);
2554 gold::relocate_section
<32, false, Target_i386
, elfcpp::SHT_REL
,
2555 Target_i386::Relocate
>(
2561 needs_special_offset_handling
,
2565 reloc_symbol_changes
);
2568 // Return the size of a relocation while scanning during a relocatable
2572 Target_i386::Relocatable_size_for_reloc::get_size_for_reloc(
2573 unsigned int r_type
,
2578 case elfcpp::R_386_NONE
:
2579 case elfcpp::R_386_GNU_VTINHERIT
:
2580 case elfcpp::R_386_GNU_VTENTRY
:
2581 case elfcpp::R_386_TLS_GD
: // Global-dynamic
2582 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
2583 case elfcpp::R_386_TLS_DESC_CALL
:
2584 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
2585 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
2586 case elfcpp::R_386_TLS_IE
: // Initial-exec
2587 case elfcpp::R_386_TLS_IE_32
:
2588 case elfcpp::R_386_TLS_GOTIE
:
2589 case elfcpp::R_386_TLS_LE
: // Local-exec
2590 case elfcpp::R_386_TLS_LE_32
:
2593 case elfcpp::R_386_32
:
2594 case elfcpp::R_386_PC32
:
2595 case elfcpp::R_386_GOT32
:
2596 case elfcpp::R_386_PLT32
:
2597 case elfcpp::R_386_GOTOFF
:
2598 case elfcpp::R_386_GOTPC
:
2601 case elfcpp::R_386_16
:
2602 case elfcpp::R_386_PC16
:
2605 case elfcpp::R_386_8
:
2606 case elfcpp::R_386_PC8
:
2609 // These are relocations which should only be seen by the
2610 // dynamic linker, and should never be seen here.
2611 case elfcpp::R_386_COPY
:
2612 case elfcpp::R_386_GLOB_DAT
:
2613 case elfcpp::R_386_JUMP_SLOT
:
2614 case elfcpp::R_386_RELATIVE
:
2615 case elfcpp::R_386_TLS_TPOFF
:
2616 case elfcpp::R_386_TLS_DTPMOD32
:
2617 case elfcpp::R_386_TLS_DTPOFF32
:
2618 case elfcpp::R_386_TLS_TPOFF32
:
2619 case elfcpp::R_386_TLS_DESC
:
2620 object
->error(_("unexpected reloc %u in object file"), r_type
);
2623 case elfcpp::R_386_32PLT
:
2624 case elfcpp::R_386_TLS_GD_32
:
2625 case elfcpp::R_386_TLS_GD_PUSH
:
2626 case elfcpp::R_386_TLS_GD_CALL
:
2627 case elfcpp::R_386_TLS_GD_POP
:
2628 case elfcpp::R_386_TLS_LDM_32
:
2629 case elfcpp::R_386_TLS_LDM_PUSH
:
2630 case elfcpp::R_386_TLS_LDM_CALL
:
2631 case elfcpp::R_386_TLS_LDM_POP
:
2632 case elfcpp::R_386_USED_BY_INTEL_200
:
2634 object
->error(_("unsupported reloc %u in object file"), r_type
);
2639 // Scan the relocs during a relocatable link.
2642 Target_i386::scan_relocatable_relocs(Symbol_table
* symtab
,
2644 Sized_relobj
<32, false>* object
,
2645 unsigned int data_shndx
,
2646 unsigned int sh_type
,
2647 const unsigned char* prelocs
,
2649 Output_section
* output_section
,
2650 bool needs_special_offset_handling
,
2651 size_t local_symbol_count
,
2652 const unsigned char* plocal_symbols
,
2653 Relocatable_relocs
* rr
)
2655 gold_assert(sh_type
== elfcpp::SHT_REL
);
2657 typedef gold::Default_scan_relocatable_relocs
<elfcpp::SHT_REL
,
2658 Relocatable_size_for_reloc
> Scan_relocatable_relocs
;
2660 gold::scan_relocatable_relocs
<32, false, elfcpp::SHT_REL
,
2661 Scan_relocatable_relocs
>(
2669 needs_special_offset_handling
,
2675 // Relocate a section during a relocatable link.
2678 Target_i386::relocate_for_relocatable(
2679 const Relocate_info
<32, false>* relinfo
,
2680 unsigned int sh_type
,
2681 const unsigned char* prelocs
,
2683 Output_section
* output_section
,
2684 off_t offset_in_output_section
,
2685 const Relocatable_relocs
* rr
,
2686 unsigned char* view
,
2687 elfcpp::Elf_types
<32>::Elf_Addr view_address
,
2688 section_size_type view_size
,
2689 unsigned char* reloc_view
,
2690 section_size_type reloc_view_size
)
2692 gold_assert(sh_type
== elfcpp::SHT_REL
);
2694 gold::relocate_for_relocatable
<32, false, elfcpp::SHT_REL
>(
2699 offset_in_output_section
,
2708 // Return the value to use for a dynamic which requires special
2709 // treatment. This is how we support equality comparisons of function
2710 // pointers across shared library boundaries, as described in the
2711 // processor specific ABI supplement.
2714 Target_i386::do_dynsym_value(const Symbol
* gsym
) const
2716 gold_assert(gsym
->is_from_dynobj() && gsym
->has_plt_offset());
2717 return this->plt_section()->address() + gsym
->plt_offset();
2720 // Return a string used to fill a code section with nops to take up
2721 // the specified length.
2724 Target_i386::do_code_fill(section_size_type length
) const
2728 // Build a jmp instruction to skip over the bytes.
2729 unsigned char jmp
[5];
2731 elfcpp::Swap_unaligned
<32, false>::writeval(jmp
+ 1, length
- 5);
2732 return (std::string(reinterpret_cast<char*>(&jmp
[0]), 5)
2733 + std::string(length
- 5, '\0'));
2736 // Nop sequences of various lengths.
2737 const char nop1
[1] = { 0x90 }; // nop
2738 const char nop2
[2] = { 0x66, 0x90 }; // xchg %ax %ax
2739 const char nop3
[3] = { 0x8d, 0x76, 0x00 }; // leal 0(%esi),%esi
2740 const char nop4
[4] = { 0x8d, 0x74, 0x26, 0x00}; // leal 0(%esi,1),%esi
2741 const char nop5
[5] = { 0x90, 0x8d, 0x74, 0x26, // nop
2742 0x00 }; // leal 0(%esi,1),%esi
2743 const char nop6
[6] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2745 const char nop7
[7] = { 0x8d, 0xb4, 0x26, 0x00, // leal 0L(%esi,1),%esi
2747 const char nop8
[8] = { 0x90, 0x8d, 0xb4, 0x26, // nop
2748 0x00, 0x00, 0x00, 0x00 }; // leal 0L(%esi,1),%esi
2749 const char nop9
[9] = { 0x89, 0xf6, 0x8d, 0xbc, // movl %esi,%esi
2750 0x27, 0x00, 0x00, 0x00, // leal 0L(%edi,1),%edi
2752 const char nop10
[10] = { 0x8d, 0x76, 0x00, 0x8d, // leal 0(%esi),%esi
2753 0xbc, 0x27, 0x00, 0x00, // leal 0L(%edi,1),%edi
2755 const char nop11
[11] = { 0x8d, 0x74, 0x26, 0x00, // leal 0(%esi,1),%esi
2756 0x8d, 0xbc, 0x27, 0x00, // leal 0L(%edi,1),%edi
2758 const char nop12
[12] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2759 0x00, 0x00, 0x8d, 0xbf, // leal 0L(%edi),%edi
2760 0x00, 0x00, 0x00, 0x00 };
2761 const char nop13
[13] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2762 0x00, 0x00, 0x8d, 0xbc, // leal 0L(%edi,1),%edi
2763 0x27, 0x00, 0x00, 0x00,
2765 const char nop14
[14] = { 0x8d, 0xb4, 0x26, 0x00, // leal 0L(%esi,1),%esi
2766 0x00, 0x00, 0x00, 0x8d, // leal 0L(%edi,1),%edi
2767 0xbc, 0x27, 0x00, 0x00,
2769 const char nop15
[15] = { 0xeb, 0x0d, 0x90, 0x90, // jmp .+15
2770 0x90, 0x90, 0x90, 0x90, // nop,nop,nop,...
2771 0x90, 0x90, 0x90, 0x90,
2774 const char* nops
[16] = {
2776 nop1
, nop2
, nop3
, nop4
, nop5
, nop6
, nop7
,
2777 nop8
, nop9
, nop10
, nop11
, nop12
, nop13
, nop14
, nop15
2780 return std::string(nops
[length
], length
);
2783 // Return whether SYM should be treated as a call to a non-split
2784 // function. We don't want that to be true of a call to a
2785 // get_pc_thunk function.
2788 Target_i386::do_is_call_to_non_split(const Symbol
* sym
, unsigned int) const
2790 return (sym
->type() == elfcpp::STT_FUNC
2791 && !is_prefix_of("__i686.get_pc_thunk.", sym
->name()));
2794 // FNOFFSET in section SHNDX in OBJECT is the start of a function
2795 // compiled with -fstack-split. The function calls non-stack-split
2796 // code. We have to change the function so that it always ensures
2797 // that it has enough stack space to run some random function.
2800 Target_i386::do_calls_non_split(Relobj
* object
, unsigned int shndx
,
2801 section_offset_type fnoffset
,
2802 section_size_type fnsize
,
2803 unsigned char* view
,
2804 section_size_type view_size
,
2806 std::string
* to
) const
2808 // The function starts with a comparison of the stack pointer and a
2809 // field in the TCB. This is followed by a jump.
2812 if (this->match_view(view
, view_size
, fnoffset
, "\x65\x3b\x25", 3)
2815 // We will call __morestack if the carry flag is set after this
2816 // comparison. We turn the comparison into an stc instruction
2818 view
[fnoffset
] = '\xf9';
2819 this->set_view_to_nop(view
, view_size
, fnoffset
+ 1, 6);
2821 // lea NN(%esp),%ecx
2822 // lea NN(%esp),%edx
2823 else if ((this->match_view(view
, view_size
, fnoffset
, "\x8d\x8c\x24", 3)
2824 || this->match_view(view
, view_size
, fnoffset
, "\x8d\x94\x24", 3))
2827 // This is loading an offset from the stack pointer for a
2828 // comparison. The offset is negative, so we decrease the
2829 // offset by the amount of space we need for the stack. This
2830 // means we will avoid calling __morestack if there happens to
2831 // be plenty of space on the stack already.
2832 unsigned char* pval
= view
+ fnoffset
+ 3;
2833 uint32_t val
= elfcpp::Swap_unaligned
<32, false>::readval(pval
);
2834 val
-= parameters
->options().split_stack_adjust_size();
2835 elfcpp::Swap_unaligned
<32, false>::writeval(pval
, val
);
2839 if (!object
->has_no_split_stack())
2840 object
->error(_("failed to match split-stack sequence at "
2841 "section %u offset %0zx"),
2842 shndx
, static_cast<size_t>(fnoffset
));
2846 // We have to change the function so that it calls
2847 // __morestack_non_split instead of __morestack. The former will
2848 // allocate additional stack space.
2849 *from
= "__morestack";
2850 *to
= "__morestack_non_split";
2853 // The selector for i386 object files.
2855 class Target_selector_i386
: public Target_selector_freebsd
2858 Target_selector_i386()
2859 : Target_selector_freebsd(elfcpp::EM_386
, 32, false,
2860 "elf32-i386", "elf32-i386-freebsd")
2864 do_instantiate_target()
2865 { return new Target_i386(); }
2868 Target_selector_i386 target_selector_i386
;
2870 } // End anonymous namespace.