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>();
497 layout
->add_output_section_data(".got", elfcpp::SHT_PROGBITS
,
499 | elfcpp::SHF_WRITE
),
500 this->got_
, false, true, true, false);
502 this->got_plt_
= new Output_data_space(4, "** GOT PLT");
503 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
505 | elfcpp::SHF_WRITE
),
506 this->got_plt_
, false, false, false,
509 // The first three entries are reserved.
510 this->got_plt_
->set_current_data_size(3 * 4);
512 // Those bytes can go into the relro segment.
513 layout
->increase_relro(3 * 4);
515 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
516 this->global_offset_table_
=
517 symtab
->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL
,
518 Symbol_table::PREDEFINED
,
520 0, 0, elfcpp::STT_OBJECT
,
522 elfcpp::STV_HIDDEN
, 0,
529 // Get the dynamic reloc section, creating it if necessary.
531 Target_i386::Reloc_section
*
532 Target_i386::rel_dyn_section(Layout
* layout
)
534 if (this->rel_dyn_
== NULL
)
536 gold_assert(layout
!= NULL
);
537 this->rel_dyn_
= new Reloc_section(parameters
->options().combreloc());
538 layout
->add_output_section_data(".rel.dyn", elfcpp::SHT_REL
,
539 elfcpp::SHF_ALLOC
, this->rel_dyn_
, true,
540 false, false, false);
542 return this->rel_dyn_
;
545 // A class to handle the PLT data.
547 class Output_data_plt_i386
: public Output_section_data
550 typedef Output_data_reloc
<elfcpp::SHT_REL
, true, 32, false> Reloc_section
;
552 Output_data_plt_i386(Layout
*, Output_data_space
*);
554 // Add an entry to the PLT.
556 add_entry(Symbol
* gsym
);
558 // Return the .rel.plt section data.
561 { return this->rel_
; }
563 // Return where the TLS_DESC relocations should go.
565 rel_tls_desc(Layout
*);
569 do_adjust_output_section(Output_section
* os
);
571 // Write to a map file.
573 do_print_to_mapfile(Mapfile
* mapfile
) const
574 { mapfile
->print_output_data(this, _("** PLT")); }
577 // The size of an entry in the PLT.
578 static const int plt_entry_size
= 16;
580 // The first entry in the PLT for an executable.
581 static unsigned char exec_first_plt_entry
[plt_entry_size
];
583 // The first entry in the PLT for a shared object.
584 static unsigned char dyn_first_plt_entry
[plt_entry_size
];
586 // Other entries in the PLT for an executable.
587 static unsigned char exec_plt_entry
[plt_entry_size
];
589 // Other entries in the PLT for a shared object.
590 static unsigned char dyn_plt_entry
[plt_entry_size
];
592 // Set the final size.
594 set_final_data_size()
595 { this->set_data_size((this->count_
+ 1) * plt_entry_size
); }
597 // Write out the PLT data.
599 do_write(Output_file
*);
601 // The reloc section.
603 // The TLS_DESC relocations, if necessary. These must follow the
604 // regular PLT relocs.
605 Reloc_section
* tls_desc_rel_
;
606 // The .got.plt section.
607 Output_data_space
* got_plt_
;
608 // The number of PLT entries.
612 // Create the PLT section. The ordinary .got section is an argument,
613 // since we need to refer to the start. We also create our own .got
614 // section just for PLT entries.
616 Output_data_plt_i386::Output_data_plt_i386(Layout
* layout
,
617 Output_data_space
* got_plt
)
618 : Output_section_data(4), tls_desc_rel_(NULL
), got_plt_(got_plt
), count_(0)
620 this->rel_
= new Reloc_section(false);
621 layout
->add_output_section_data(".rel.plt", elfcpp::SHT_REL
,
622 elfcpp::SHF_ALLOC
, this->rel_
, true,
623 false, false, false);
627 Output_data_plt_i386::do_adjust_output_section(Output_section
* os
)
629 // UnixWare sets the entsize of .plt to 4, and so does the old GNU
630 // linker, and so do we.
634 // Add an entry to the PLT.
637 Output_data_plt_i386::add_entry(Symbol
* gsym
)
639 gold_assert(!gsym
->has_plt_offset());
641 // Note that when setting the PLT offset we skip the initial
642 // reserved PLT entry.
643 gsym
->set_plt_offset((this->count_
+ 1) * plt_entry_size
);
647 section_offset_type got_offset
= this->got_plt_
->current_data_size();
649 // Every PLT entry needs a GOT entry which points back to the PLT
650 // entry (this will be changed by the dynamic linker, normally
651 // lazily when the function is called).
652 this->got_plt_
->set_current_data_size(got_offset
+ 4);
654 // Every PLT entry needs a reloc.
655 gsym
->set_needs_dynsym_entry();
656 this->rel_
->add_global(gsym
, elfcpp::R_386_JUMP_SLOT
, this->got_plt_
,
659 // Note that we don't need to save the symbol. The contents of the
660 // PLT are independent of which symbols are used. The symbols only
661 // appear in the relocations.
664 // Return where the TLS_DESC relocations should go, creating it if
665 // necessary. These follow the JUMP_SLOT relocations.
667 Output_data_plt_i386::Reloc_section
*
668 Output_data_plt_i386::rel_tls_desc(Layout
* layout
)
670 if (this->tls_desc_rel_
== NULL
)
672 this->tls_desc_rel_
= new Reloc_section(false);
673 layout
->add_output_section_data(".rel.plt", elfcpp::SHT_REL
,
674 elfcpp::SHF_ALLOC
, this->tls_desc_rel_
,
675 true, false, false, false);
676 gold_assert(this->tls_desc_rel_
->output_section() ==
677 this->rel_
->output_section());
679 return this->tls_desc_rel_
;
682 // The first entry in the PLT for an executable.
684 unsigned char Output_data_plt_i386::exec_first_plt_entry
[plt_entry_size
] =
686 0xff, 0x35, // pushl contents of memory address
687 0, 0, 0, 0, // replaced with address of .got + 4
688 0xff, 0x25, // jmp indirect
689 0, 0, 0, 0, // replaced with address of .got + 8
693 // The first entry in the PLT for a shared object.
695 unsigned char Output_data_plt_i386::dyn_first_plt_entry
[plt_entry_size
] =
697 0xff, 0xb3, 4, 0, 0, 0, // pushl 4(%ebx)
698 0xff, 0xa3, 8, 0, 0, 0, // jmp *8(%ebx)
702 // Subsequent entries in the PLT for an executable.
704 unsigned char Output_data_plt_i386::exec_plt_entry
[plt_entry_size
] =
706 0xff, 0x25, // jmp indirect
707 0, 0, 0, 0, // replaced with address of symbol in .got
708 0x68, // pushl immediate
709 0, 0, 0, 0, // replaced with offset into relocation table
710 0xe9, // jmp relative
711 0, 0, 0, 0 // replaced with offset to start of .plt
714 // Subsequent entries in the PLT for a shared object.
716 unsigned char Output_data_plt_i386::dyn_plt_entry
[plt_entry_size
] =
718 0xff, 0xa3, // jmp *offset(%ebx)
719 0, 0, 0, 0, // replaced with offset of symbol in .got
720 0x68, // pushl immediate
721 0, 0, 0, 0, // replaced with offset into relocation table
722 0xe9, // jmp relative
723 0, 0, 0, 0 // replaced with offset to start of .plt
726 // Write out the PLT. This uses the hand-coded instructions above,
727 // and adjusts them as needed. This is all specified by the i386 ELF
728 // Processor Supplement.
731 Output_data_plt_i386::do_write(Output_file
* of
)
733 const off_t offset
= this->offset();
734 const section_size_type oview_size
=
735 convert_to_section_size_type(this->data_size());
736 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
738 const off_t got_file_offset
= this->got_plt_
->offset();
739 const section_size_type got_size
=
740 convert_to_section_size_type(this->got_plt_
->data_size());
741 unsigned char* const got_view
= of
->get_output_view(got_file_offset
,
744 unsigned char* pov
= oview
;
746 elfcpp::Elf_types
<32>::Elf_Addr plt_address
= this->address();
747 elfcpp::Elf_types
<32>::Elf_Addr got_address
= this->got_plt_
->address();
749 if (parameters
->options().output_is_position_independent())
750 memcpy(pov
, dyn_first_plt_entry
, plt_entry_size
);
753 memcpy(pov
, exec_first_plt_entry
, plt_entry_size
);
754 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2, got_address
+ 4);
755 elfcpp::Swap
<32, false>::writeval(pov
+ 8, got_address
+ 8);
757 pov
+= plt_entry_size
;
759 unsigned char* got_pov
= got_view
;
761 memset(got_pov
, 0, 12);
764 const int rel_size
= elfcpp::Elf_sizes
<32>::rel_size
;
766 unsigned int plt_offset
= plt_entry_size
;
767 unsigned int plt_rel_offset
= 0;
768 unsigned int got_offset
= 12;
769 const unsigned int count
= this->count_
;
770 for (unsigned int i
= 0;
773 pov
+= plt_entry_size
,
775 plt_offset
+= plt_entry_size
,
776 plt_rel_offset
+= rel_size
,
779 // Set and adjust the PLT entry itself.
781 if (parameters
->options().output_is_position_independent())
783 memcpy(pov
, dyn_plt_entry
, plt_entry_size
);
784 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2, got_offset
);
788 memcpy(pov
, exec_plt_entry
, plt_entry_size
);
789 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
794 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 7, plt_rel_offset
);
795 elfcpp::Swap
<32, false>::writeval(pov
+ 12,
796 - (plt_offset
+ plt_entry_size
));
798 // Set the entry in the GOT.
799 elfcpp::Swap
<32, false>::writeval(got_pov
, plt_address
+ plt_offset
+ 6);
802 gold_assert(static_cast<section_size_type
>(pov
- oview
) == oview_size
);
803 gold_assert(static_cast<section_size_type
>(got_pov
- got_view
) == got_size
);
805 of
->write_output_view(offset
, oview_size
, oview
);
806 of
->write_output_view(got_file_offset
, got_size
, got_view
);
809 // Create a PLT entry for a global symbol.
812 Target_i386::make_plt_entry(Symbol_table
* symtab
, Layout
* layout
, Symbol
* gsym
)
814 if (gsym
->has_plt_offset())
817 if (this->plt_
== NULL
)
819 // Create the GOT sections first.
820 this->got_section(symtab
, layout
);
822 this->plt_
= new Output_data_plt_i386(layout
, this->got_plt_
);
823 layout
->add_output_section_data(".plt", elfcpp::SHT_PROGBITS
,
825 | elfcpp::SHF_EXECINSTR
),
826 this->plt_
, false, false, false, false);
829 this->plt_
->add_entry(gsym
);
832 // Get the section to use for TLS_DESC relocations.
834 Target_i386::Reloc_section
*
835 Target_i386::rel_tls_desc_section(Layout
* layout
) const
837 return this->plt_section()->rel_tls_desc(layout
);
840 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
843 Target_i386::define_tls_base_symbol(Symbol_table
* symtab
, Layout
* layout
)
845 if (this->tls_base_symbol_defined_
)
848 Output_segment
* tls_segment
= layout
->tls_segment();
849 if (tls_segment
!= NULL
)
851 bool is_exec
= parameters
->options().output_is_executable();
852 symtab
->define_in_output_segment("_TLS_MODULE_BASE_", NULL
,
853 Symbol_table::PREDEFINED
,
857 elfcpp::STV_HIDDEN
, 0,
859 ? Symbol::SEGMENT_END
860 : Symbol::SEGMENT_START
),
863 this->tls_base_symbol_defined_
= true;
866 // Create a GOT entry for the TLS module index.
869 Target_i386::got_mod_index_entry(Symbol_table
* symtab
, Layout
* layout
,
870 Sized_relobj
<32, false>* object
)
872 if (this->got_mod_index_offset_
== -1U)
874 gold_assert(symtab
!= NULL
&& layout
!= NULL
&& object
!= NULL
);
875 Reloc_section
* rel_dyn
= this->rel_dyn_section(layout
);
876 Output_data_got
<32, false>* got
= this->got_section(symtab
, layout
);
877 unsigned int got_offset
= got
->add_constant(0);
878 rel_dyn
->add_local(object
, 0, elfcpp::R_386_TLS_DTPMOD32
, got
,
880 got
->add_constant(0);
881 this->got_mod_index_offset_
= got_offset
;
883 return this->got_mod_index_offset_
;
886 // Optimize the TLS relocation type based on what we know about the
887 // symbol. IS_FINAL is true if the final address of this symbol is
888 // known at link time.
890 tls::Tls_optimization
891 Target_i386::optimize_tls_reloc(bool is_final
, int r_type
)
893 // If we are generating a shared library, then we can't do anything
895 if (parameters
->options().shared())
896 return tls::TLSOPT_NONE
;
900 case elfcpp::R_386_TLS_GD
:
901 case elfcpp::R_386_TLS_GOTDESC
:
902 case elfcpp::R_386_TLS_DESC_CALL
:
903 // These are General-Dynamic which permits fully general TLS
904 // access. Since we know that we are generating an executable,
905 // we can convert this to Initial-Exec. If we also know that
906 // this is a local symbol, we can further switch to Local-Exec.
908 return tls::TLSOPT_TO_LE
;
909 return tls::TLSOPT_TO_IE
;
911 case elfcpp::R_386_TLS_LDM
:
912 // This is Local-Dynamic, which refers to a local symbol in the
913 // dynamic TLS block. Since we know that we generating an
914 // executable, we can switch to Local-Exec.
915 return tls::TLSOPT_TO_LE
;
917 case elfcpp::R_386_TLS_LDO_32
:
918 // Another type of Local-Dynamic relocation.
919 return tls::TLSOPT_TO_LE
;
921 case elfcpp::R_386_TLS_IE
:
922 case elfcpp::R_386_TLS_GOTIE
:
923 case elfcpp::R_386_TLS_IE_32
:
924 // These are Initial-Exec relocs which get the thread offset
925 // from the GOT. If we know that we are linking against the
926 // local symbol, we can switch to Local-Exec, which links the
927 // thread offset into the instruction.
929 return tls::TLSOPT_TO_LE
;
930 return tls::TLSOPT_NONE
;
932 case elfcpp::R_386_TLS_LE
:
933 case elfcpp::R_386_TLS_LE_32
:
934 // When we already have Local-Exec, there is nothing further we
936 return tls::TLSOPT_NONE
;
943 // Report an unsupported relocation against a local symbol.
946 Target_i386::Scan::unsupported_reloc_local(Sized_relobj
<32, false>* object
,
949 gold_error(_("%s: unsupported reloc %u against local symbol"),
950 object
->name().c_str(), r_type
);
953 // Scan a relocation for a local symbol.
956 Target_i386::Scan::local(Symbol_table
* symtab
,
959 Sized_relobj
<32, false>* object
,
960 unsigned int data_shndx
,
961 Output_section
* output_section
,
962 const elfcpp::Rel
<32, false>& reloc
,
964 const elfcpp::Sym
<32, false>& lsym
)
968 case elfcpp::R_386_NONE
:
969 case elfcpp::R_386_GNU_VTINHERIT
:
970 case elfcpp::R_386_GNU_VTENTRY
:
973 case elfcpp::R_386_32
:
974 // If building a shared library (or a position-independent
975 // executable), we need to create a dynamic relocation for
976 // this location. The relocation applied at link time will
977 // apply the link-time value, so we flag the location with
978 // an R_386_RELATIVE relocation so the dynamic loader can
979 // relocate it easily.
980 if (parameters
->options().output_is_position_independent())
982 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
983 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
984 rel_dyn
->add_local_relative(object
, r_sym
, elfcpp::R_386_RELATIVE
,
985 output_section
, data_shndx
,
986 reloc
.get_r_offset());
990 case elfcpp::R_386_16
:
991 case elfcpp::R_386_8
:
992 // If building a shared library (or a position-independent
993 // executable), we need to create a dynamic relocation for
994 // this location. Because the addend needs to remain in the
995 // data section, we need to be careful not to apply this
996 // relocation statically.
997 if (parameters
->options().output_is_position_independent())
999 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1000 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1001 if (lsym
.get_st_type() != elfcpp::STT_SECTION
)
1002 rel_dyn
->add_local(object
, r_sym
, r_type
, output_section
,
1003 data_shndx
, reloc
.get_r_offset());
1006 gold_assert(lsym
.get_st_value() == 0);
1007 unsigned int shndx
= lsym
.get_st_shndx();
1009 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
,
1012 object
->error(_("section symbol %u has bad shndx %u"),
1015 rel_dyn
->add_local_section(object
, shndx
,
1016 r_type
, output_section
,
1017 data_shndx
, reloc
.get_r_offset());
1022 case elfcpp::R_386_PC32
:
1023 case elfcpp::R_386_PC16
:
1024 case elfcpp::R_386_PC8
:
1027 case elfcpp::R_386_PLT32
:
1028 // Since we know this is a local symbol, we can handle this as a
1032 case elfcpp::R_386_GOTOFF
:
1033 case elfcpp::R_386_GOTPC
:
1034 // We need a GOT section.
1035 target
->got_section(symtab
, layout
);
1038 case elfcpp::R_386_GOT32
:
1040 // The symbol requires a GOT entry.
1041 Output_data_got
<32, false>* got
= target
->got_section(symtab
, layout
);
1042 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1043 if (got
->add_local(object
, r_sym
, GOT_TYPE_STANDARD
))
1045 // If we are generating a shared object, we need to add a
1046 // dynamic RELATIVE relocation for this symbol's GOT entry.
1047 if (parameters
->options().output_is_position_independent())
1049 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1050 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1051 rel_dyn
->add_local_relative(
1052 object
, r_sym
, elfcpp::R_386_RELATIVE
, got
,
1053 object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
));
1059 // These are relocations which should only be seen by the
1060 // dynamic linker, and should never be seen here.
1061 case elfcpp::R_386_COPY
:
1062 case elfcpp::R_386_GLOB_DAT
:
1063 case elfcpp::R_386_JUMP_SLOT
:
1064 case elfcpp::R_386_RELATIVE
:
1065 case elfcpp::R_386_TLS_TPOFF
:
1066 case elfcpp::R_386_TLS_DTPMOD32
:
1067 case elfcpp::R_386_TLS_DTPOFF32
:
1068 case elfcpp::R_386_TLS_TPOFF32
:
1069 case elfcpp::R_386_TLS_DESC
:
1070 gold_error(_("%s: unexpected reloc %u in object file"),
1071 object
->name().c_str(), r_type
);
1074 // These are initial TLS relocs, which are expected when
1076 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1077 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
1078 case elfcpp::R_386_TLS_DESC_CALL
:
1079 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1080 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1081 case elfcpp::R_386_TLS_IE
: // Initial-exec
1082 case elfcpp::R_386_TLS_IE_32
:
1083 case elfcpp::R_386_TLS_GOTIE
:
1084 case elfcpp::R_386_TLS_LE
: // Local-exec
1085 case elfcpp::R_386_TLS_LE_32
:
1087 bool output_is_shared
= parameters
->options().shared();
1088 const tls::Tls_optimization optimized_type
1089 = Target_i386::optimize_tls_reloc(!output_is_shared
, r_type
);
1092 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1093 if (optimized_type
== tls::TLSOPT_NONE
)
1095 // Create a pair of GOT entries for the module index and
1096 // dtv-relative offset.
1097 Output_data_got
<32, false>* got
1098 = target
->got_section(symtab
, layout
);
1099 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1100 unsigned int shndx
= lsym
.get_st_shndx();
1102 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
, &is_ordinary
);
1104 object
->error(_("local symbol %u has bad shndx %u"),
1107 got
->add_local_pair_with_rel(object
, r_sym
, shndx
,
1109 target
->rel_dyn_section(layout
),
1110 elfcpp::R_386_TLS_DTPMOD32
, 0);
1112 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1113 unsupported_reloc_local(object
, r_type
);
1116 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva)
1117 target
->define_tls_base_symbol(symtab
, layout
);
1118 if (optimized_type
== tls::TLSOPT_NONE
)
1120 // Create a double GOT entry with an R_386_TLS_DESC reloc.
1121 Output_data_got
<32, false>* got
1122 = target
->got_section(symtab
, layout
);
1123 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1124 if (!object
->local_has_got_offset(r_sym
, GOT_TYPE_TLS_DESC
))
1126 unsigned int got_offset
= got
->add_constant(0);
1127 // The local symbol value is stored in the second
1129 got
->add_local(object
, r_sym
, GOT_TYPE_TLS_DESC
);
1130 // That set the GOT offset of the local symbol to
1131 // point to the second entry, but we want it to
1132 // point to the first.
1133 object
->set_local_got_offset(r_sym
, GOT_TYPE_TLS_DESC
,
1135 Reloc_section
* rt
= target
->rel_tls_desc_section(layout
);
1136 rt
->add_absolute(elfcpp::R_386_TLS_DESC
, got
, got_offset
);
1139 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1140 unsupported_reloc_local(object
, r_type
);
1143 case elfcpp::R_386_TLS_DESC_CALL
:
1146 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1147 if (optimized_type
== tls::TLSOPT_NONE
)
1149 // Create a GOT entry for the module index.
1150 target
->got_mod_index_entry(symtab
, layout
, object
);
1152 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1153 unsupported_reloc_local(object
, r_type
);
1156 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1159 case elfcpp::R_386_TLS_IE
: // Initial-exec
1160 case elfcpp::R_386_TLS_IE_32
:
1161 case elfcpp::R_386_TLS_GOTIE
:
1162 layout
->set_has_static_tls();
1163 if (optimized_type
== tls::TLSOPT_NONE
)
1165 // For the R_386_TLS_IE relocation, we need to create a
1166 // dynamic relocation when building a shared library.
1167 if (r_type
== elfcpp::R_386_TLS_IE
1168 && parameters
->options().shared())
1170 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1172 = elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1173 rel_dyn
->add_local_relative(object
, r_sym
,
1174 elfcpp::R_386_RELATIVE
,
1175 output_section
, data_shndx
,
1176 reloc
.get_r_offset());
1178 // Create a GOT entry for the tp-relative offset.
1179 Output_data_got
<32, false>* got
1180 = target
->got_section(symtab
, layout
);
1181 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1182 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_IE_32
1183 ? elfcpp::R_386_TLS_TPOFF32
1184 : elfcpp::R_386_TLS_TPOFF
);
1185 unsigned int got_type
= (r_type
== elfcpp::R_386_TLS_IE_32
1186 ? GOT_TYPE_TLS_OFFSET
1187 : GOT_TYPE_TLS_NOFFSET
);
1188 got
->add_local_with_rel(object
, r_sym
, got_type
,
1189 target
->rel_dyn_section(layout
),
1192 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1193 unsupported_reloc_local(object
, r_type
);
1196 case elfcpp::R_386_TLS_LE
: // Local-exec
1197 case elfcpp::R_386_TLS_LE_32
:
1198 layout
->set_has_static_tls();
1199 if (output_is_shared
)
1201 // We need to create a dynamic relocation.
1202 gold_assert(lsym
.get_st_type() != elfcpp::STT_SECTION
);
1203 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1204 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_LE_32
1205 ? elfcpp::R_386_TLS_TPOFF32
1206 : elfcpp::R_386_TLS_TPOFF
);
1207 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1208 rel_dyn
->add_local(object
, r_sym
, dyn_r_type
, output_section
,
1209 data_shndx
, reloc
.get_r_offset());
1219 case elfcpp::R_386_32PLT
:
1220 case elfcpp::R_386_TLS_GD_32
:
1221 case elfcpp::R_386_TLS_GD_PUSH
:
1222 case elfcpp::R_386_TLS_GD_CALL
:
1223 case elfcpp::R_386_TLS_GD_POP
:
1224 case elfcpp::R_386_TLS_LDM_32
:
1225 case elfcpp::R_386_TLS_LDM_PUSH
:
1226 case elfcpp::R_386_TLS_LDM_CALL
:
1227 case elfcpp::R_386_TLS_LDM_POP
:
1228 case elfcpp::R_386_USED_BY_INTEL_200
:
1230 unsupported_reloc_local(object
, r_type
);
1235 // Report an unsupported relocation against a global symbol.
1238 Target_i386::Scan::unsupported_reloc_global(Sized_relobj
<32, false>* object
,
1239 unsigned int r_type
,
1242 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
1243 object
->name().c_str(), r_type
, gsym
->demangled_name().c_str());
1247 Target_i386::Scan::possible_function_pointer_reloc(unsigned int r_type
)
1251 case elfcpp::R_386_32
:
1252 case elfcpp::R_386_16
:
1253 case elfcpp::R_386_8
:
1254 case elfcpp::R_386_GOTOFF
:
1255 case elfcpp::R_386_GOT32
:
1266 Target_i386::Scan::local_reloc_may_be_function_pointer(
1270 Sized_relobj
<32, false>* ,
1273 const elfcpp::Rel
<32, false>& ,
1274 unsigned int r_type
,
1275 const elfcpp::Sym
<32, false>&)
1277 return possible_function_pointer_reloc(r_type
);
1281 Target_i386::Scan::global_reloc_may_be_function_pointer(
1285 Sized_relobj
<32, false>* ,
1288 const elfcpp::Rel
<32, false>& ,
1289 unsigned int r_type
,
1292 return possible_function_pointer_reloc(r_type
);
1295 // Scan a relocation for a global symbol.
1298 Target_i386::Scan::global(Symbol_table
* symtab
,
1300 Target_i386
* target
,
1301 Sized_relobj
<32, false>* object
,
1302 unsigned int data_shndx
,
1303 Output_section
* output_section
,
1304 const elfcpp::Rel
<32, false>& reloc
,
1305 unsigned int r_type
,
1310 case elfcpp::R_386_NONE
:
1311 case elfcpp::R_386_GNU_VTINHERIT
:
1312 case elfcpp::R_386_GNU_VTENTRY
:
1315 case elfcpp::R_386_32
:
1316 case elfcpp::R_386_16
:
1317 case elfcpp::R_386_8
:
1319 // Make a PLT entry if necessary.
1320 if (gsym
->needs_plt_entry())
1322 target
->make_plt_entry(symtab
, layout
, gsym
);
1323 // Since this is not a PC-relative relocation, we may be
1324 // taking the address of a function. In that case we need to
1325 // set the entry in the dynamic symbol table to the address of
1327 if (gsym
->is_from_dynobj() && !parameters
->options().shared())
1328 gsym
->set_needs_dynsym_value();
1330 // Make a dynamic relocation if necessary.
1331 if (gsym
->needs_dynamic_reloc(Symbol::ABSOLUTE_REF
))
1333 if (gsym
->may_need_copy_reloc())
1335 target
->copy_reloc(symtab
, layout
, object
,
1336 data_shndx
, output_section
, gsym
, reloc
);
1338 else if (r_type
== elfcpp::R_386_32
1339 && gsym
->can_use_relative_reloc(false))
1341 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1342 rel_dyn
->add_global_relative(gsym
, elfcpp::R_386_RELATIVE
,
1343 output_section
, object
,
1344 data_shndx
, reloc
.get_r_offset());
1348 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1349 rel_dyn
->add_global(gsym
, r_type
, output_section
, object
,
1350 data_shndx
, reloc
.get_r_offset());
1356 case elfcpp::R_386_PC32
:
1357 case elfcpp::R_386_PC16
:
1358 case elfcpp::R_386_PC8
:
1360 // Make a PLT entry if necessary.
1361 if (gsym
->needs_plt_entry())
1363 // These relocations are used for function calls only in
1364 // non-PIC code. For a 32-bit relocation in a shared library,
1365 // we'll need a text relocation anyway, so we can skip the
1366 // PLT entry and let the dynamic linker bind the call directly
1367 // to the target. For smaller relocations, we should use a
1368 // PLT entry to ensure that the call can reach.
1369 if (!parameters
->options().shared()
1370 || r_type
!= elfcpp::R_386_PC32
)
1371 target
->make_plt_entry(symtab
, layout
, gsym
);
1373 // Make a dynamic relocation if necessary.
1374 int flags
= Symbol::NON_PIC_REF
;
1375 if (gsym
->is_func())
1376 flags
|= Symbol::FUNCTION_CALL
;
1377 if (gsym
->needs_dynamic_reloc(flags
))
1379 if (gsym
->may_need_copy_reloc())
1381 target
->copy_reloc(symtab
, layout
, object
,
1382 data_shndx
, output_section
, gsym
, reloc
);
1386 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1387 rel_dyn
->add_global(gsym
, r_type
, output_section
, object
,
1388 data_shndx
, reloc
.get_r_offset());
1394 case elfcpp::R_386_GOT32
:
1396 // The symbol requires a GOT entry.
1397 Output_data_got
<32, false>* got
= target
->got_section(symtab
, layout
);
1398 if (gsym
->final_value_is_known())
1399 got
->add_global(gsym
, GOT_TYPE_STANDARD
);
1402 // If this symbol is not fully resolved, we need to add a
1403 // GOT entry with a dynamic relocation.
1404 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1405 if (gsym
->is_from_dynobj()
1406 || gsym
->is_undefined()
1407 || gsym
->is_preemptible())
1408 got
->add_global_with_rel(gsym
, GOT_TYPE_STANDARD
,
1409 rel_dyn
, elfcpp::R_386_GLOB_DAT
);
1412 if (got
->add_global(gsym
, GOT_TYPE_STANDARD
))
1413 rel_dyn
->add_global_relative(
1414 gsym
, elfcpp::R_386_RELATIVE
, got
,
1415 gsym
->got_offset(GOT_TYPE_STANDARD
));
1421 case elfcpp::R_386_PLT32
:
1422 // If the symbol is fully resolved, this is just a PC32 reloc.
1423 // Otherwise we need a PLT entry.
1424 if (gsym
->final_value_is_known())
1426 // If building a shared library, we can also skip the PLT entry
1427 // if the symbol is defined in the output file and is protected
1429 if (gsym
->is_defined()
1430 && !gsym
->is_from_dynobj()
1431 && !gsym
->is_preemptible())
1433 target
->make_plt_entry(symtab
, layout
, gsym
);
1436 case elfcpp::R_386_GOTOFF
:
1437 case elfcpp::R_386_GOTPC
:
1438 // We need a GOT section.
1439 target
->got_section(symtab
, layout
);
1442 // These are relocations which should only be seen by the
1443 // dynamic linker, and should never be seen here.
1444 case elfcpp::R_386_COPY
:
1445 case elfcpp::R_386_GLOB_DAT
:
1446 case elfcpp::R_386_JUMP_SLOT
:
1447 case elfcpp::R_386_RELATIVE
:
1448 case elfcpp::R_386_TLS_TPOFF
:
1449 case elfcpp::R_386_TLS_DTPMOD32
:
1450 case elfcpp::R_386_TLS_DTPOFF32
:
1451 case elfcpp::R_386_TLS_TPOFF32
:
1452 case elfcpp::R_386_TLS_DESC
:
1453 gold_error(_("%s: unexpected reloc %u in object file"),
1454 object
->name().c_str(), r_type
);
1457 // These are initial tls relocs, which are expected when
1459 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1460 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
1461 case elfcpp::R_386_TLS_DESC_CALL
:
1462 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1463 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1464 case elfcpp::R_386_TLS_IE
: // Initial-exec
1465 case elfcpp::R_386_TLS_IE_32
:
1466 case elfcpp::R_386_TLS_GOTIE
:
1467 case elfcpp::R_386_TLS_LE
: // Local-exec
1468 case elfcpp::R_386_TLS_LE_32
:
1470 const bool is_final
= gsym
->final_value_is_known();
1471 const tls::Tls_optimization optimized_type
1472 = Target_i386::optimize_tls_reloc(is_final
, r_type
);
1475 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1476 if (optimized_type
== tls::TLSOPT_NONE
)
1478 // Create a pair of GOT entries for the module index and
1479 // dtv-relative offset.
1480 Output_data_got
<32, false>* got
1481 = target
->got_section(symtab
, layout
);
1482 got
->add_global_pair_with_rel(gsym
, GOT_TYPE_TLS_PAIR
,
1483 target
->rel_dyn_section(layout
),
1484 elfcpp::R_386_TLS_DTPMOD32
,
1485 elfcpp::R_386_TLS_DTPOFF32
);
1487 else if (optimized_type
== tls::TLSOPT_TO_IE
)
1489 // Create a GOT entry for the tp-relative offset.
1490 Output_data_got
<32, false>* got
1491 = target
->got_section(symtab
, layout
);
1492 got
->add_global_with_rel(gsym
, GOT_TYPE_TLS_NOFFSET
,
1493 target
->rel_dyn_section(layout
),
1494 elfcpp::R_386_TLS_TPOFF
);
1496 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1497 unsupported_reloc_global(object
, r_type
, gsym
);
1500 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (~oliva url)
1501 target
->define_tls_base_symbol(symtab
, layout
);
1502 if (optimized_type
== tls::TLSOPT_NONE
)
1504 // Create a double GOT entry with an R_386_TLS_DESC reloc.
1505 Output_data_got
<32, false>* got
1506 = target
->got_section(symtab
, layout
);
1507 Reloc_section
* rt
= target
->rel_tls_desc_section(layout
);
1508 got
->add_global_pair_with_rel(gsym
, GOT_TYPE_TLS_DESC
, rt
,
1509 elfcpp::R_386_TLS_DESC
, 0);
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_DESC_CALL
:
1527 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1528 if (optimized_type
== tls::TLSOPT_NONE
)
1530 // Create a GOT entry for the module index.
1531 target
->got_mod_index_entry(symtab
, layout
, object
);
1533 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1534 unsupported_reloc_global(object
, r_type
, gsym
);
1537 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1540 case elfcpp::R_386_TLS_IE
: // Initial-exec
1541 case elfcpp::R_386_TLS_IE_32
:
1542 case elfcpp::R_386_TLS_GOTIE
:
1543 layout
->set_has_static_tls();
1544 if (optimized_type
== tls::TLSOPT_NONE
)
1546 // For the R_386_TLS_IE relocation, we need to create a
1547 // dynamic relocation when building a shared library.
1548 if (r_type
== elfcpp::R_386_TLS_IE
1549 && parameters
->options().shared())
1551 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1552 rel_dyn
->add_global_relative(gsym
, elfcpp::R_386_RELATIVE
,
1553 output_section
, object
,
1555 reloc
.get_r_offset());
1557 // Create a GOT entry for the tp-relative offset.
1558 Output_data_got
<32, false>* got
1559 = target
->got_section(symtab
, layout
);
1560 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_IE_32
1561 ? elfcpp::R_386_TLS_TPOFF32
1562 : elfcpp::R_386_TLS_TPOFF
);
1563 unsigned int got_type
= (r_type
== elfcpp::R_386_TLS_IE_32
1564 ? GOT_TYPE_TLS_OFFSET
1565 : GOT_TYPE_TLS_NOFFSET
);
1566 got
->add_global_with_rel(gsym
, got_type
,
1567 target
->rel_dyn_section(layout
),
1570 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1571 unsupported_reloc_global(object
, r_type
, gsym
);
1574 case elfcpp::R_386_TLS_LE
: // Local-exec
1575 case elfcpp::R_386_TLS_LE_32
:
1576 layout
->set_has_static_tls();
1577 if (parameters
->options().shared())
1579 // We need to create a dynamic relocation.
1580 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_LE_32
1581 ? elfcpp::R_386_TLS_TPOFF32
1582 : elfcpp::R_386_TLS_TPOFF
);
1583 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1584 rel_dyn
->add_global(gsym
, dyn_r_type
, output_section
, object
,
1585 data_shndx
, reloc
.get_r_offset());
1595 case elfcpp::R_386_32PLT
:
1596 case elfcpp::R_386_TLS_GD_32
:
1597 case elfcpp::R_386_TLS_GD_PUSH
:
1598 case elfcpp::R_386_TLS_GD_CALL
:
1599 case elfcpp::R_386_TLS_GD_POP
:
1600 case elfcpp::R_386_TLS_LDM_32
:
1601 case elfcpp::R_386_TLS_LDM_PUSH
:
1602 case elfcpp::R_386_TLS_LDM_CALL
:
1603 case elfcpp::R_386_TLS_LDM_POP
:
1604 case elfcpp::R_386_USED_BY_INTEL_200
:
1606 unsupported_reloc_global(object
, r_type
, gsym
);
1611 // Process relocations for gc.
1614 Target_i386::gc_process_relocs(Symbol_table
* symtab
,
1616 Sized_relobj
<32, false>* object
,
1617 unsigned int data_shndx
,
1619 const unsigned char* prelocs
,
1621 Output_section
* output_section
,
1622 bool needs_special_offset_handling
,
1623 size_t local_symbol_count
,
1624 const unsigned char* plocal_symbols
)
1626 gold::gc_process_relocs
<32, false, Target_i386
, elfcpp::SHT_REL
,
1636 needs_special_offset_handling
,
1641 // Scan relocations for a section.
1644 Target_i386::scan_relocs(Symbol_table
* symtab
,
1646 Sized_relobj
<32, false>* object
,
1647 unsigned int data_shndx
,
1648 unsigned int sh_type
,
1649 const unsigned char* prelocs
,
1651 Output_section
* output_section
,
1652 bool needs_special_offset_handling
,
1653 size_t local_symbol_count
,
1654 const unsigned char* plocal_symbols
)
1656 if (sh_type
== elfcpp::SHT_RELA
)
1658 gold_error(_("%s: unsupported RELA reloc section"),
1659 object
->name().c_str());
1663 gold::scan_relocs
<32, false, Target_i386
, elfcpp::SHT_REL
,
1673 needs_special_offset_handling
,
1678 // Finalize the sections.
1681 Target_i386::do_finalize_sections(
1683 const Input_objects
*,
1684 Symbol_table
* symtab
)
1686 const Reloc_section
* rel_plt
= (this->plt_
== NULL
1688 : this->plt_
->rel_plt());
1689 layout
->add_target_dynamic_tags(true, this->got_plt_
, rel_plt
,
1690 this->rel_dyn_
, true, false);
1692 // Emit any relocs we saved in an attempt to avoid generating COPY
1694 if (this->copy_relocs_
.any_saved_relocs())
1695 this->copy_relocs_
.emit(this->rel_dyn_section(layout
));
1697 // Set the size of the _GLOBAL_OFFSET_TABLE_ symbol to the size of
1698 // the .got.plt section.
1699 Symbol
* sym
= this->global_offset_table_
;
1702 uint32_t data_size
= this->got_plt_
->current_data_size();
1703 symtab
->get_sized_symbol
<32>(sym
)->set_symsize(data_size
);
1707 // Return whether a direct absolute static relocation needs to be applied.
1708 // In cases where Scan::local() or Scan::global() has created
1709 // a dynamic relocation other than R_386_RELATIVE, the addend
1710 // of the relocation is carried in the data, and we must not
1711 // apply the static relocation.
1714 Target_i386::Relocate::should_apply_static_reloc(const Sized_symbol
<32>* gsym
,
1717 Output_section
* output_section
)
1719 // If the output section is not allocated, then we didn't call
1720 // scan_relocs, we didn't create a dynamic reloc, and we must apply
1722 if ((output_section
->flags() & elfcpp::SHF_ALLOC
) == 0)
1725 // For local symbols, we will have created a non-RELATIVE dynamic
1726 // relocation only if (a) the output is position independent,
1727 // (b) the relocation is absolute (not pc- or segment-relative), and
1728 // (c) the relocation is not 32 bits wide.
1730 return !(parameters
->options().output_is_position_independent()
1731 && (ref_flags
& Symbol::ABSOLUTE_REF
)
1734 // For global symbols, we use the same helper routines used in the
1735 // scan pass. If we did not create a dynamic relocation, or if we
1736 // created a RELATIVE dynamic relocation, we should apply the static
1738 bool has_dyn
= gsym
->needs_dynamic_reloc(ref_flags
);
1739 bool is_rel
= (ref_flags
& Symbol::ABSOLUTE_REF
)
1740 && gsym
->can_use_relative_reloc(ref_flags
1741 & Symbol::FUNCTION_CALL
);
1742 return !has_dyn
|| is_rel
;
1745 // Perform a relocation.
1748 Target_i386::Relocate::relocate(const Relocate_info
<32, false>* relinfo
,
1749 Target_i386
* target
,
1750 Output_section
*output_section
,
1752 const elfcpp::Rel
<32, false>& rel
,
1753 unsigned int r_type
,
1754 const Sized_symbol
<32>* gsym
,
1755 const Symbol_value
<32>* psymval
,
1756 unsigned char* view
,
1757 elfcpp::Elf_types
<32>::Elf_Addr address
,
1758 section_size_type view_size
)
1760 if (this->skip_call_tls_get_addr_
)
1762 if ((r_type
!= elfcpp::R_386_PLT32
1763 && r_type
!= elfcpp::R_386_PC32
)
1765 || strcmp(gsym
->name(), "___tls_get_addr") != 0)
1766 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
1767 _("missing expected TLS relocation"));
1770 this->skip_call_tls_get_addr_
= false;
1775 // Pick the value to use for symbols defined in shared objects.
1776 Symbol_value
<32> symval
;
1778 && gsym
->use_plt_offset(r_type
== elfcpp::R_386_PC8
1779 || r_type
== elfcpp::R_386_PC16
1780 || r_type
== elfcpp::R_386_PC32
))
1782 symval
.set_output_value(target
->plt_section()->address()
1783 + gsym
->plt_offset());
1787 const Sized_relobj
<32, false>* object
= relinfo
->object
;
1789 // Get the GOT offset if needed.
1790 // The GOT pointer points to the end of the GOT section.
1791 // We need to subtract the size of the GOT section to get
1792 // the actual offset to use in the relocation.
1793 bool have_got_offset
= false;
1794 unsigned int got_offset
= 0;
1797 case elfcpp::R_386_GOT32
:
1800 gold_assert(gsym
->has_got_offset(GOT_TYPE_STANDARD
));
1801 got_offset
= (gsym
->got_offset(GOT_TYPE_STANDARD
)
1802 - target
->got_size());
1806 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
1807 gold_assert(object
->local_has_got_offset(r_sym
, GOT_TYPE_STANDARD
));
1808 got_offset
= (object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
)
1809 - target
->got_size());
1811 have_got_offset
= true;
1820 case elfcpp::R_386_NONE
:
1821 case elfcpp::R_386_GNU_VTINHERIT
:
1822 case elfcpp::R_386_GNU_VTENTRY
:
1825 case elfcpp::R_386_32
:
1826 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, true,
1828 Relocate_functions
<32, false>::rel32(view
, object
, psymval
);
1831 case elfcpp::R_386_PC32
:
1833 int ref_flags
= Symbol::NON_PIC_REF
;
1834 if (gsym
!= NULL
&& gsym
->is_func())
1835 ref_flags
|= Symbol::FUNCTION_CALL
;
1836 if (should_apply_static_reloc(gsym
, ref_flags
, true, output_section
))
1837 Relocate_functions
<32, false>::pcrel32(view
, object
, psymval
, address
);
1841 case elfcpp::R_386_16
:
1842 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, false,
1844 Relocate_functions
<32, false>::rel16(view
, object
, psymval
);
1847 case elfcpp::R_386_PC16
:
1849 int ref_flags
= Symbol::NON_PIC_REF
;
1850 if (gsym
!= NULL
&& gsym
->is_func())
1851 ref_flags
|= Symbol::FUNCTION_CALL
;
1852 if (should_apply_static_reloc(gsym
, ref_flags
, false, output_section
))
1853 Relocate_functions
<32, false>::pcrel16(view
, object
, psymval
, address
);
1857 case elfcpp::R_386_8
:
1858 if (should_apply_static_reloc(gsym
, Symbol::ABSOLUTE_REF
, false,
1860 Relocate_functions
<32, false>::rel8(view
, object
, psymval
);
1863 case elfcpp::R_386_PC8
:
1865 int ref_flags
= Symbol::NON_PIC_REF
;
1866 if (gsym
!= NULL
&& gsym
->is_func())
1867 ref_flags
|= Symbol::FUNCTION_CALL
;
1868 if (should_apply_static_reloc(gsym
, ref_flags
, false,
1870 Relocate_functions
<32, false>::pcrel8(view
, object
, psymval
, address
);
1874 case elfcpp::R_386_PLT32
:
1875 gold_assert(gsym
== NULL
1876 || gsym
->has_plt_offset()
1877 || gsym
->final_value_is_known()
1878 || (gsym
->is_defined()
1879 && !gsym
->is_from_dynobj()
1880 && !gsym
->is_preemptible()));
1881 Relocate_functions
<32, false>::pcrel32(view
, object
, psymval
, address
);
1884 case elfcpp::R_386_GOT32
:
1885 gold_assert(have_got_offset
);
1886 Relocate_functions
<32, false>::rel32(view
, got_offset
);
1889 case elfcpp::R_386_GOTOFF
:
1891 elfcpp::Elf_types
<32>::Elf_Addr value
;
1892 value
= (psymval
->value(object
, 0)
1893 - target
->got_plt_section()->address());
1894 Relocate_functions
<32, false>::rel32(view
, value
);
1898 case elfcpp::R_386_GOTPC
:
1900 elfcpp::Elf_types
<32>::Elf_Addr value
;
1901 value
= target
->got_plt_section()->address();
1902 Relocate_functions
<32, false>::pcrel32(view
, value
, address
);
1906 case elfcpp::R_386_COPY
:
1907 case elfcpp::R_386_GLOB_DAT
:
1908 case elfcpp::R_386_JUMP_SLOT
:
1909 case elfcpp::R_386_RELATIVE
:
1910 // These are outstanding tls relocs, which are unexpected when
1912 case elfcpp::R_386_TLS_TPOFF
:
1913 case elfcpp::R_386_TLS_DTPMOD32
:
1914 case elfcpp::R_386_TLS_DTPOFF32
:
1915 case elfcpp::R_386_TLS_TPOFF32
:
1916 case elfcpp::R_386_TLS_DESC
:
1917 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
1918 _("unexpected reloc %u in object file"),
1922 // These are initial tls relocs, which are expected when
1924 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1925 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
1926 case elfcpp::R_386_TLS_DESC_CALL
:
1927 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1928 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1929 case elfcpp::R_386_TLS_IE
: // Initial-exec
1930 case elfcpp::R_386_TLS_IE_32
:
1931 case elfcpp::R_386_TLS_GOTIE
:
1932 case elfcpp::R_386_TLS_LE
: // Local-exec
1933 case elfcpp::R_386_TLS_LE_32
:
1934 this->relocate_tls(relinfo
, target
, relnum
, rel
, r_type
, gsym
, psymval
,
1935 view
, address
, view_size
);
1938 case elfcpp::R_386_32PLT
:
1939 case elfcpp::R_386_TLS_GD_32
:
1940 case elfcpp::R_386_TLS_GD_PUSH
:
1941 case elfcpp::R_386_TLS_GD_CALL
:
1942 case elfcpp::R_386_TLS_GD_POP
:
1943 case elfcpp::R_386_TLS_LDM_32
:
1944 case elfcpp::R_386_TLS_LDM_PUSH
:
1945 case elfcpp::R_386_TLS_LDM_CALL
:
1946 case elfcpp::R_386_TLS_LDM_POP
:
1947 case elfcpp::R_386_USED_BY_INTEL_200
:
1949 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
1950 _("unsupported reloc %u"),
1958 // Perform a TLS relocation.
1961 Target_i386::Relocate::relocate_tls(const Relocate_info
<32, false>* relinfo
,
1962 Target_i386
* target
,
1964 const elfcpp::Rel
<32, false>& rel
,
1965 unsigned int r_type
,
1966 const Sized_symbol
<32>* gsym
,
1967 const Symbol_value
<32>* psymval
,
1968 unsigned char* view
,
1969 elfcpp::Elf_types
<32>::Elf_Addr
,
1970 section_size_type view_size
)
1972 Output_segment
* tls_segment
= relinfo
->layout
->tls_segment();
1974 const Sized_relobj
<32, false>* object
= relinfo
->object
;
1976 elfcpp::Elf_types
<32>::Elf_Addr value
= psymval
->value(object
, 0);
1978 const bool is_final
= (gsym
== NULL
1979 ? !parameters
->options().shared()
1980 : gsym
->final_value_is_known());
1981 const tls::Tls_optimization optimized_type
1982 = Target_i386::optimize_tls_reloc(is_final
, r_type
);
1985 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1986 if (optimized_type
== tls::TLSOPT_TO_LE
)
1988 gold_assert(tls_segment
!= NULL
);
1989 this->tls_gd_to_le(relinfo
, relnum
, tls_segment
,
1990 rel
, r_type
, value
, view
,
1996 unsigned int got_type
= (optimized_type
== tls::TLSOPT_TO_IE
1997 ? GOT_TYPE_TLS_NOFFSET
1998 : GOT_TYPE_TLS_PAIR
);
1999 unsigned int got_offset
;
2002 gold_assert(gsym
->has_got_offset(got_type
));
2003 got_offset
= gsym
->got_offset(got_type
) - target
->got_size();
2007 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
2008 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
2009 got_offset
= (object
->local_got_offset(r_sym
, got_type
)
2010 - target
->got_size());
2012 if (optimized_type
== tls::TLSOPT_TO_IE
)
2014 gold_assert(tls_segment
!= NULL
);
2015 this->tls_gd_to_ie(relinfo
, relnum
, tls_segment
, rel
, r_type
,
2016 got_offset
, view
, view_size
);
2019 else if (optimized_type
== tls::TLSOPT_NONE
)
2021 // Relocate the field with the offset of the pair of GOT
2023 Relocate_functions
<32, false>::rel32(view
, got_offset
);
2027 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2028 _("unsupported reloc %u"),
2032 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
2033 case elfcpp::R_386_TLS_DESC_CALL
:
2034 this->local_dynamic_type_
= LOCAL_DYNAMIC_GNU
;
2035 if (optimized_type
== tls::TLSOPT_TO_LE
)
2037 gold_assert(tls_segment
!= NULL
);
2038 this->tls_desc_gd_to_le(relinfo
, relnum
, tls_segment
,
2039 rel
, r_type
, value
, view
,
2045 unsigned int got_type
= (optimized_type
== tls::TLSOPT_TO_IE
2046 ? GOT_TYPE_TLS_NOFFSET
2047 : GOT_TYPE_TLS_DESC
);
2048 unsigned int got_offset
;
2051 gold_assert(gsym
->has_got_offset(got_type
));
2052 got_offset
= gsym
->got_offset(got_type
) - target
->got_size();
2056 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
2057 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
2058 got_offset
= (object
->local_got_offset(r_sym
, got_type
)
2059 - target
->got_size());
2061 if (optimized_type
== tls::TLSOPT_TO_IE
)
2063 gold_assert(tls_segment
!= NULL
);
2064 this->tls_desc_gd_to_ie(relinfo
, relnum
, tls_segment
, rel
, r_type
,
2065 got_offset
, view
, view_size
);
2068 else if (optimized_type
== tls::TLSOPT_NONE
)
2070 if (r_type
== elfcpp::R_386_TLS_GOTDESC
)
2072 // Relocate the field with the offset of the pair of GOT
2074 Relocate_functions
<32, false>::rel32(view
, got_offset
);
2079 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2080 _("unsupported reloc %u"),
2084 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
2085 if (this->local_dynamic_type_
== LOCAL_DYNAMIC_SUN
)
2087 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2088 _("both SUN and GNU model "
2089 "TLS relocations"));
2092 this->local_dynamic_type_
= LOCAL_DYNAMIC_GNU
;
2093 if (optimized_type
== tls::TLSOPT_TO_LE
)
2095 gold_assert(tls_segment
!= NULL
);
2096 this->tls_ld_to_le(relinfo
, relnum
, tls_segment
, rel
, r_type
,
2097 value
, view
, view_size
);
2100 else if (optimized_type
== tls::TLSOPT_NONE
)
2102 // Relocate the field with the offset of the GOT entry for
2103 // the module index.
2104 unsigned int got_offset
;
2105 got_offset
= (target
->got_mod_index_entry(NULL
, NULL
, NULL
)
2106 - target
->got_size());
2107 Relocate_functions
<32, false>::rel32(view
, got_offset
);
2110 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2111 _("unsupported reloc %u"),
2115 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
2116 if (optimized_type
== tls::TLSOPT_TO_LE
)
2118 // This reloc can appear in debugging sections, in which
2119 // case we must not convert to local-exec. We decide what
2120 // to do based on whether the section is marked as
2121 // containing executable code. That is what the GNU linker
2123 elfcpp::Shdr
<32, false> shdr(relinfo
->data_shdr
);
2124 if ((shdr
.get_sh_flags() & elfcpp::SHF_EXECINSTR
) != 0)
2126 gold_assert(tls_segment
!= NULL
);
2127 value
-= tls_segment
->memsz();
2130 Relocate_functions
<32, false>::rel32(view
, value
);
2133 case elfcpp::R_386_TLS_IE
: // Initial-exec
2134 case elfcpp::R_386_TLS_GOTIE
:
2135 case elfcpp::R_386_TLS_IE_32
:
2136 if (optimized_type
== tls::TLSOPT_TO_LE
)
2138 gold_assert(tls_segment
!= NULL
);
2139 Target_i386::Relocate::tls_ie_to_le(relinfo
, relnum
, tls_segment
,
2140 rel
, r_type
, value
, view
,
2144 else if (optimized_type
== tls::TLSOPT_NONE
)
2146 // Relocate the field with the offset of the GOT entry for
2147 // the tp-relative offset of the symbol.
2148 unsigned int got_type
= (r_type
== elfcpp::R_386_TLS_IE_32
2149 ? GOT_TYPE_TLS_OFFSET
2150 : GOT_TYPE_TLS_NOFFSET
);
2151 unsigned int got_offset
;
2154 gold_assert(gsym
->has_got_offset(got_type
));
2155 got_offset
= gsym
->got_offset(got_type
);
2159 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
2160 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
2161 got_offset
= object
->local_got_offset(r_sym
, got_type
);
2163 // For the R_386_TLS_IE relocation, we need to apply the
2164 // absolute address of the GOT entry.
2165 if (r_type
== elfcpp::R_386_TLS_IE
)
2166 got_offset
+= target
->got_plt_section()->address();
2167 // All GOT offsets are relative to the end of the GOT.
2168 got_offset
-= target
->got_size();
2169 Relocate_functions
<32, false>::rel32(view
, got_offset
);
2172 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2173 _("unsupported reloc %u"),
2177 case elfcpp::R_386_TLS_LE
: // Local-exec
2178 // If we're creating a shared library, a dynamic relocation will
2179 // have been created for this location, so do not apply it now.
2180 if (!parameters
->options().shared())
2182 gold_assert(tls_segment
!= NULL
);
2183 value
-= tls_segment
->memsz();
2184 Relocate_functions
<32, false>::rel32(view
, value
);
2188 case elfcpp::R_386_TLS_LE_32
:
2189 // If we're creating a shared library, a dynamic relocation will
2190 // have been created for this location, so do not apply it now.
2191 if (!parameters
->options().shared())
2193 gold_assert(tls_segment
!= NULL
);
2194 value
= tls_segment
->memsz() - value
;
2195 Relocate_functions
<32, false>::rel32(view
, value
);
2201 // Do a relocation in which we convert a TLS General-Dynamic to a
2205 Target_i386::Relocate::tls_gd_to_le(const Relocate_info
<32, false>* relinfo
,
2207 Output_segment
* tls_segment
,
2208 const elfcpp::Rel
<32, false>& rel
,
2210 elfcpp::Elf_types
<32>::Elf_Addr value
,
2211 unsigned char* view
,
2212 section_size_type view_size
)
2214 // leal foo(,%reg,1),%eax; call ___tls_get_addr
2215 // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
2216 // leal foo(%reg),%eax; call ___tls_get_addr
2217 // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
2219 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2220 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 9);
2222 unsigned char op1
= view
[-1];
2223 unsigned char op2
= view
[-2];
2225 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2226 op2
== 0x8d || op2
== 0x04);
2227 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[4] == 0xe8);
2233 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -3);
2234 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[-3] == 0x8d);
2235 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2236 ((op1
& 0xc7) == 0x05 && op1
!= (4 << 3)));
2237 memcpy(view
- 3, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
2241 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2242 (op1
& 0xf8) == 0x80 && (op1
& 7) != 4);
2243 if (rel
.get_r_offset() + 9 < view_size
2246 // There is a trailing nop. Use the size byte subl.
2247 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
2252 // Use the five byte subl.
2253 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
2257 value
= tls_segment
->memsz() - value
;
2258 Relocate_functions
<32, false>::rel32(view
+ roff
, value
);
2260 // The next reloc should be a PLT32 reloc against __tls_get_addr.
2262 this->skip_call_tls_get_addr_
= true;
2265 // Do a relocation in which we convert a TLS General-Dynamic to an
2269 Target_i386::Relocate::tls_gd_to_ie(const Relocate_info
<32, false>* relinfo
,
2272 const elfcpp::Rel
<32, false>& rel
,
2274 elfcpp::Elf_types
<32>::Elf_Addr value
,
2275 unsigned char* view
,
2276 section_size_type view_size
)
2278 // leal foo(,%ebx,1),%eax; call ___tls_get_addr
2279 // ==> movl %gs:0,%eax; addl foo@gotntpoff(%ebx),%eax
2281 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2282 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 9);
2284 unsigned char op1
= view
[-1];
2285 unsigned char op2
= view
[-2];
2287 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2288 op2
== 0x8d || op2
== 0x04);
2289 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[4] == 0xe8);
2293 // FIXME: For now, support only the first (SIB) form.
2294 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), op2
== 0x04);
2298 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -3);
2299 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[-3] == 0x8d);
2300 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2301 ((op1
& 0xc7) == 0x05 && op1
!= (4 << 3)));
2302 memcpy(view
- 3, "\x65\xa1\0\0\0\0\x03\x83\0\0\0", 12);
2306 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2307 (op1
& 0xf8) == 0x80 && (op1
& 7) != 4);
2308 if (rel
.get_r_offset() + 9 < view_size
2311 // FIXME: This is not the right instruction sequence.
2312 // There is a trailing nop. Use the size byte subl.
2313 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
2318 // FIXME: This is not the right instruction sequence.
2319 // Use the five byte subl.
2320 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
2324 Relocate_functions
<32, false>::rel32(view
+ roff
, value
);
2326 // The next reloc should be a PLT32 reloc against __tls_get_addr.
2328 this->skip_call_tls_get_addr_
= true;
2331 // Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL
2332 // General-Dynamic to a Local-Exec.
2335 Target_i386::Relocate::tls_desc_gd_to_le(
2336 const Relocate_info
<32, false>* relinfo
,
2338 Output_segment
* tls_segment
,
2339 const elfcpp::Rel
<32, false>& rel
,
2340 unsigned int r_type
,
2341 elfcpp::Elf_types
<32>::Elf_Addr value
,
2342 unsigned char* view
,
2343 section_size_type view_size
)
2345 if (r_type
== elfcpp::R_386_TLS_GOTDESC
)
2347 // leal foo@TLSDESC(%ebx), %eax
2348 // ==> leal foo@NTPOFF, %eax
2349 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2350 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
2351 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2352 view
[-2] == 0x8d && view
[-1] == 0x83);
2354 value
-= tls_segment
->memsz();
2355 Relocate_functions
<32, false>::rel32(view
, value
);
2359 // call *foo@TLSCALL(%eax)
2361 gold_assert(r_type
== elfcpp::R_386_TLS_DESC_CALL
);
2362 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 2);
2363 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2364 view
[0] == 0xff && view
[1] == 0x10);
2370 // Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL
2371 // General-Dynamic to an Initial-Exec.
2374 Target_i386::Relocate::tls_desc_gd_to_ie(
2375 const Relocate_info
<32, false>* relinfo
,
2378 const elfcpp::Rel
<32, false>& rel
,
2379 unsigned int r_type
,
2380 elfcpp::Elf_types
<32>::Elf_Addr value
,
2381 unsigned char* view
,
2382 section_size_type view_size
)
2384 if (r_type
== elfcpp::R_386_TLS_GOTDESC
)
2386 // leal foo@TLSDESC(%ebx), %eax
2387 // ==> movl foo@GOTNTPOFF(%ebx), %eax
2388 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2389 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
2390 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2391 view
[-2] == 0x8d && view
[-1] == 0x83);
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 Local-Dynamic to a
2412 Target_i386::Relocate::tls_ld_to_le(const Relocate_info
<32, false>* relinfo
,
2415 const elfcpp::Rel
<32, false>& rel
,
2417 elfcpp::Elf_types
<32>::Elf_Addr
,
2418 unsigned char* view
,
2419 section_size_type view_size
)
2421 // leal foo(%reg), %eax; call ___tls_get_addr
2422 // ==> movl %gs:0,%eax; nop; leal 0(%esi,1),%esi
2424 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2425 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 9);
2427 // FIXME: Does this test really always pass?
2428 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2429 view
[-2] == 0x8d && view
[-1] == 0x83);
2431 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[4] == 0xe8);
2433 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x90\x8d\x74\x26\0", 11);
2435 // The next reloc should be a PLT32 reloc against __tls_get_addr.
2437 this->skip_call_tls_get_addr_
= true;
2440 // Do a relocation in which we convert a TLS Initial-Exec to a
2444 Target_i386::Relocate::tls_ie_to_le(const Relocate_info
<32, false>* relinfo
,
2446 Output_segment
* tls_segment
,
2447 const elfcpp::Rel
<32, false>& rel
,
2448 unsigned int r_type
,
2449 elfcpp::Elf_types
<32>::Elf_Addr value
,
2450 unsigned char* view
,
2451 section_size_type view_size
)
2453 // We have to actually change the instructions, which means that we
2454 // need to examine the opcodes to figure out which instruction we
2456 if (r_type
== elfcpp::R_386_TLS_IE
)
2458 // movl %gs:XX,%eax ==> movl $YY,%eax
2459 // movl %gs:XX,%reg ==> movl $YY,%reg
2460 // addl %gs:XX,%reg ==> addl $YY,%reg
2461 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -1);
2462 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
2464 unsigned char op1
= view
[-1];
2467 // movl XX,%eax ==> movl $YY,%eax
2472 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2474 unsigned char op2
= view
[-2];
2477 // movl XX,%reg ==> movl $YY,%reg
2478 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2479 (op1
& 0xc7) == 0x05);
2481 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
2483 else if (op2
== 0x03)
2485 // addl XX,%reg ==> addl $YY,%reg
2486 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2487 (op1
& 0xc7) == 0x05);
2489 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
2492 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), 0);
2497 // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2
2498 // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2
2499 // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2
2500 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2501 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
2503 unsigned char op1
= view
[-1];
2504 unsigned char op2
= view
[-2];
2505 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2506 (op1
& 0xc0) == 0x80 && (op1
& 7) != 4);
2509 // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2
2511 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
2513 else if (op2
== 0x2b)
2515 // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2
2517 view
[-1] = 0xe8 | ((op1
>> 3) & 7);
2519 else if (op2
== 0x03)
2521 // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2
2523 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
2526 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), 0);
2529 value
= tls_segment
->memsz() - value
;
2530 if (r_type
== elfcpp::R_386_TLS_IE
|| r_type
== elfcpp::R_386_TLS_GOTIE
)
2533 Relocate_functions
<32, false>::rel32(view
, value
);
2536 // Relocate section data.
2539 Target_i386::relocate_section(const Relocate_info
<32, false>* relinfo
,
2540 unsigned int sh_type
,
2541 const unsigned char* prelocs
,
2543 Output_section
* output_section
,
2544 bool needs_special_offset_handling
,
2545 unsigned char* view
,
2546 elfcpp::Elf_types
<32>::Elf_Addr address
,
2547 section_size_type view_size
,
2548 const Reloc_symbol_changes
* reloc_symbol_changes
)
2550 gold_assert(sh_type
== elfcpp::SHT_REL
);
2552 gold::relocate_section
<32, false, Target_i386
, elfcpp::SHT_REL
,
2553 Target_i386::Relocate
>(
2559 needs_special_offset_handling
,
2563 reloc_symbol_changes
);
2566 // Return the size of a relocation while scanning during a relocatable
2570 Target_i386::Relocatable_size_for_reloc::get_size_for_reloc(
2571 unsigned int r_type
,
2576 case elfcpp::R_386_NONE
:
2577 case elfcpp::R_386_GNU_VTINHERIT
:
2578 case elfcpp::R_386_GNU_VTENTRY
:
2579 case elfcpp::R_386_TLS_GD
: // Global-dynamic
2580 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
2581 case elfcpp::R_386_TLS_DESC_CALL
:
2582 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
2583 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
2584 case elfcpp::R_386_TLS_IE
: // Initial-exec
2585 case elfcpp::R_386_TLS_IE_32
:
2586 case elfcpp::R_386_TLS_GOTIE
:
2587 case elfcpp::R_386_TLS_LE
: // Local-exec
2588 case elfcpp::R_386_TLS_LE_32
:
2591 case elfcpp::R_386_32
:
2592 case elfcpp::R_386_PC32
:
2593 case elfcpp::R_386_GOT32
:
2594 case elfcpp::R_386_PLT32
:
2595 case elfcpp::R_386_GOTOFF
:
2596 case elfcpp::R_386_GOTPC
:
2599 case elfcpp::R_386_16
:
2600 case elfcpp::R_386_PC16
:
2603 case elfcpp::R_386_8
:
2604 case elfcpp::R_386_PC8
:
2607 // These are relocations which should only be seen by the
2608 // dynamic linker, and should never be seen here.
2609 case elfcpp::R_386_COPY
:
2610 case elfcpp::R_386_GLOB_DAT
:
2611 case elfcpp::R_386_JUMP_SLOT
:
2612 case elfcpp::R_386_RELATIVE
:
2613 case elfcpp::R_386_TLS_TPOFF
:
2614 case elfcpp::R_386_TLS_DTPMOD32
:
2615 case elfcpp::R_386_TLS_DTPOFF32
:
2616 case elfcpp::R_386_TLS_TPOFF32
:
2617 case elfcpp::R_386_TLS_DESC
:
2618 object
->error(_("unexpected reloc %u in object file"), r_type
);
2621 case elfcpp::R_386_32PLT
:
2622 case elfcpp::R_386_TLS_GD_32
:
2623 case elfcpp::R_386_TLS_GD_PUSH
:
2624 case elfcpp::R_386_TLS_GD_CALL
:
2625 case elfcpp::R_386_TLS_GD_POP
:
2626 case elfcpp::R_386_TLS_LDM_32
:
2627 case elfcpp::R_386_TLS_LDM_PUSH
:
2628 case elfcpp::R_386_TLS_LDM_CALL
:
2629 case elfcpp::R_386_TLS_LDM_POP
:
2630 case elfcpp::R_386_USED_BY_INTEL_200
:
2632 object
->error(_("unsupported reloc %u in object file"), r_type
);
2637 // Scan the relocs during a relocatable link.
2640 Target_i386::scan_relocatable_relocs(Symbol_table
* symtab
,
2642 Sized_relobj
<32, false>* object
,
2643 unsigned int data_shndx
,
2644 unsigned int sh_type
,
2645 const unsigned char* prelocs
,
2647 Output_section
* output_section
,
2648 bool needs_special_offset_handling
,
2649 size_t local_symbol_count
,
2650 const unsigned char* plocal_symbols
,
2651 Relocatable_relocs
* rr
)
2653 gold_assert(sh_type
== elfcpp::SHT_REL
);
2655 typedef gold::Default_scan_relocatable_relocs
<elfcpp::SHT_REL
,
2656 Relocatable_size_for_reloc
> Scan_relocatable_relocs
;
2658 gold::scan_relocatable_relocs
<32, false, elfcpp::SHT_REL
,
2659 Scan_relocatable_relocs
>(
2667 needs_special_offset_handling
,
2673 // Relocate a section during a relocatable link.
2676 Target_i386::relocate_for_relocatable(
2677 const Relocate_info
<32, false>* relinfo
,
2678 unsigned int sh_type
,
2679 const unsigned char* prelocs
,
2681 Output_section
* output_section
,
2682 off_t offset_in_output_section
,
2683 const Relocatable_relocs
* rr
,
2684 unsigned char* view
,
2685 elfcpp::Elf_types
<32>::Elf_Addr view_address
,
2686 section_size_type view_size
,
2687 unsigned char* reloc_view
,
2688 section_size_type reloc_view_size
)
2690 gold_assert(sh_type
== elfcpp::SHT_REL
);
2692 gold::relocate_for_relocatable
<32, false, elfcpp::SHT_REL
>(
2697 offset_in_output_section
,
2706 // Return the value to use for a dynamic which requires special
2707 // treatment. This is how we support equality comparisons of function
2708 // pointers across shared library boundaries, as described in the
2709 // processor specific ABI supplement.
2712 Target_i386::do_dynsym_value(const Symbol
* gsym
) const
2714 gold_assert(gsym
->is_from_dynobj() && gsym
->has_plt_offset());
2715 return this->plt_section()->address() + gsym
->plt_offset();
2718 // Return a string used to fill a code section with nops to take up
2719 // the specified length.
2722 Target_i386::do_code_fill(section_size_type length
) const
2726 // Build a jmp instruction to skip over the bytes.
2727 unsigned char jmp
[5];
2729 elfcpp::Swap_unaligned
<32, false>::writeval(jmp
+ 1, length
- 5);
2730 return (std::string(reinterpret_cast<char*>(&jmp
[0]), 5)
2731 + std::string(length
- 5, '\0'));
2734 // Nop sequences of various lengths.
2735 const char nop1
[1] = { 0x90 }; // nop
2736 const char nop2
[2] = { 0x66, 0x90 }; // xchg %ax %ax
2737 const char nop3
[3] = { 0x8d, 0x76, 0x00 }; // leal 0(%esi),%esi
2738 const char nop4
[4] = { 0x8d, 0x74, 0x26, 0x00}; // leal 0(%esi,1),%esi
2739 const char nop5
[5] = { 0x90, 0x8d, 0x74, 0x26, // nop
2740 0x00 }; // leal 0(%esi,1),%esi
2741 const char nop6
[6] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2743 const char nop7
[7] = { 0x8d, 0xb4, 0x26, 0x00, // leal 0L(%esi,1),%esi
2745 const char nop8
[8] = { 0x90, 0x8d, 0xb4, 0x26, // nop
2746 0x00, 0x00, 0x00, 0x00 }; // leal 0L(%esi,1),%esi
2747 const char nop9
[9] = { 0x89, 0xf6, 0x8d, 0xbc, // movl %esi,%esi
2748 0x27, 0x00, 0x00, 0x00, // leal 0L(%edi,1),%edi
2750 const char nop10
[10] = { 0x8d, 0x76, 0x00, 0x8d, // leal 0(%esi),%esi
2751 0xbc, 0x27, 0x00, 0x00, // leal 0L(%edi,1),%edi
2753 const char nop11
[11] = { 0x8d, 0x74, 0x26, 0x00, // leal 0(%esi,1),%esi
2754 0x8d, 0xbc, 0x27, 0x00, // leal 0L(%edi,1),%edi
2756 const char nop12
[12] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2757 0x00, 0x00, 0x8d, 0xbf, // leal 0L(%edi),%edi
2758 0x00, 0x00, 0x00, 0x00 };
2759 const char nop13
[13] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
2760 0x00, 0x00, 0x8d, 0xbc, // leal 0L(%edi,1),%edi
2761 0x27, 0x00, 0x00, 0x00,
2763 const char nop14
[14] = { 0x8d, 0xb4, 0x26, 0x00, // leal 0L(%esi,1),%esi
2764 0x00, 0x00, 0x00, 0x8d, // leal 0L(%edi,1),%edi
2765 0xbc, 0x27, 0x00, 0x00,
2767 const char nop15
[15] = { 0xeb, 0x0d, 0x90, 0x90, // jmp .+15
2768 0x90, 0x90, 0x90, 0x90, // nop,nop,nop,...
2769 0x90, 0x90, 0x90, 0x90,
2772 const char* nops
[16] = {
2774 nop1
, nop2
, nop3
, nop4
, nop5
, nop6
, nop7
,
2775 nop8
, nop9
, nop10
, nop11
, nop12
, nop13
, nop14
, nop15
2778 return std::string(nops
[length
], length
);
2781 // Return whether SYM should be treated as a call to a non-split
2782 // function. We don't want that to be true of a call to a
2783 // get_pc_thunk function.
2786 Target_i386::do_is_call_to_non_split(const Symbol
* sym
, unsigned int) const
2788 return (sym
->type() == elfcpp::STT_FUNC
2789 && !is_prefix_of("__i686.get_pc_thunk.", sym
->name()));
2792 // FNOFFSET in section SHNDX in OBJECT is the start of a function
2793 // compiled with -fstack-split. The function calls non-stack-split
2794 // code. We have to change the function so that it always ensures
2795 // that it has enough stack space to run some random function.
2798 Target_i386::do_calls_non_split(Relobj
* object
, unsigned int shndx
,
2799 section_offset_type fnoffset
,
2800 section_size_type fnsize
,
2801 unsigned char* view
,
2802 section_size_type view_size
,
2804 std::string
* to
) const
2806 // The function starts with a comparison of the stack pointer and a
2807 // field in the TCB. This is followed by a jump.
2810 if (this->match_view(view
, view_size
, fnoffset
, "\x65\x3b\x25", 3)
2813 // We will call __morestack if the carry flag is set after this
2814 // comparison. We turn the comparison into an stc instruction
2816 view
[fnoffset
] = '\xf9';
2817 this->set_view_to_nop(view
, view_size
, fnoffset
+ 1, 6);
2819 // lea NN(%esp),%ecx
2820 // lea NN(%esp),%edx
2821 else if ((this->match_view(view
, view_size
, fnoffset
, "\x8d\x8c\x24", 3)
2822 || this->match_view(view
, view_size
, fnoffset
, "\x8d\x94\x24", 3))
2825 // This is loading an offset from the stack pointer for a
2826 // comparison. The offset is negative, so we decrease the
2827 // offset by the amount of space we need for the stack. This
2828 // means we will avoid calling __morestack if there happens to
2829 // be plenty of space on the stack already.
2830 unsigned char* pval
= view
+ fnoffset
+ 3;
2831 uint32_t val
= elfcpp::Swap_unaligned
<32, false>::readval(pval
);
2832 val
-= parameters
->options().split_stack_adjust_size();
2833 elfcpp::Swap_unaligned
<32, false>::writeval(pval
, val
);
2837 if (!object
->has_no_split_stack())
2838 object
->error(_("failed to match split-stack sequence at "
2839 "section %u offset %0zx"),
2840 shndx
, static_cast<size_t>(fnoffset
));
2844 // We have to change the function so that it calls
2845 // __morestack_non_split instead of __morestack. The former will
2846 // allocate additional stack space.
2847 *from
= "__morestack";
2848 *to
= "__morestack_non_split";
2851 // The selector for i386 object files.
2853 class Target_selector_i386
: public Target_selector_freebsd
2856 Target_selector_i386()
2857 : Target_selector_freebsd(elfcpp::EM_386
, 32, false,
2858 "elf32-i386", "elf32-i386-freebsd")
2862 do_instantiate_target()
2863 { return new Target_i386(); }
2866 Target_selector_i386 target_selector_i386
;
2868 } // End anonymous namespace.