1 // i386.cc -- i386 target support for gold.
3 // Copyright 2006, 2007, 2008, 2009, 2010, 2011 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.
29 #include "parameters.h"
36 #include "copy-relocs.h"
38 #include "target-reloc.h"
39 #include "target-select.h"
49 // A class to handle the PLT data.
51 class Output_data_plt_i386
: public Output_section_data
54 typedef Output_data_reloc
<elfcpp::SHT_REL
, true, 32, false> Reloc_section
;
56 Output_data_plt_i386(Symbol_table
*, Layout
*, Output_data_space
*);
58 // Add an entry to the PLT.
60 add_entry(Symbol
* gsym
);
62 // Add an entry to the PLT for a local STT_GNU_IFUNC symbol.
64 add_local_ifunc_entry(Sized_relobj_file
<32, false>* relobj
,
65 unsigned int local_sym_index
);
67 // Return the .rel.plt section data.
70 { return this->rel_
; }
72 // Return where the TLS_DESC relocations should go.
74 rel_tls_desc(Layout
*);
76 // Return the number of PLT entries.
79 { return this->count_
; }
81 // Return the offset of the first non-reserved PLT entry.
83 first_plt_entry_offset()
84 { return plt_entry_size
; }
86 // Return the size of a PLT entry.
89 { return plt_entry_size
; }
93 do_adjust_output_section(Output_section
* os
);
95 // Write to a map file.
97 do_print_to_mapfile(Mapfile
* mapfile
) const
98 { mapfile
->print_output_data(this, _("** PLT")); }
101 // The size of an entry in the PLT.
102 static const int plt_entry_size
= 16;
104 // The first entry in the PLT for an executable.
105 static const unsigned char exec_first_plt_entry
[plt_entry_size
];
107 // The first entry in the PLT for a shared object.
108 static const unsigned char dyn_first_plt_entry
[plt_entry_size
];
110 // Other entries in the PLT for an executable.
111 static const unsigned char exec_plt_entry
[plt_entry_size
];
113 // Other entries in the PLT for a shared object.
114 static const unsigned char dyn_plt_entry
[plt_entry_size
];
116 // The .eh_frame unwind information for the PLT.
117 static const int plt_eh_frame_cie_size
= 16;
118 static const int plt_eh_frame_fde_size
= 32;
119 static const unsigned char plt_eh_frame_cie
[plt_eh_frame_cie_size
];
120 static const unsigned char plt_eh_frame_fde
[plt_eh_frame_fde_size
];
122 // Set the final size.
124 set_final_data_size()
125 { this->set_data_size((this->count_
+ 1) * plt_entry_size
); }
127 // Write out the PLT data.
129 do_write(Output_file
*);
131 // We keep a list of global STT_GNU_IFUNC symbols, each with its
132 // offset in the GOT.
136 unsigned int got_offset
;
139 // We keep a list of local STT_GNU_IFUNC symbols, each with its
140 // offset in the GOT.
143 Sized_relobj_file
<32, false>* object
;
144 unsigned int local_sym_index
;
145 unsigned int got_offset
;
148 // The reloc section.
150 // The TLS_DESC relocations, if necessary. These must follow the
151 // regular PLT relocs.
152 Reloc_section
* tls_desc_rel_
;
153 // The .got.plt section.
154 Output_data_space
* got_plt_
;
155 // The number of PLT entries.
157 // Global STT_GNU_IFUNC symbols.
158 std::vector
<Global_ifunc
> global_ifuncs_
;
159 // Local STT_GNU_IFUNC symbols.
160 std::vector
<Local_ifunc
> local_ifuncs_
;
163 // The i386 target class.
164 // TLS info comes from
165 // http://people.redhat.com/drepper/tls.pdf
166 // http://www.lsd.ic.unicamp.br/~oliva/writeups/TLS/RFC-TLSDESC-x86.txt
168 class Target_i386
: public Sized_target
<32, false>
171 typedef Output_data_reloc
<elfcpp::SHT_REL
, true, 32, false> Reloc_section
;
174 : Sized_target
<32, false>(&i386_info
),
175 got_(NULL
), plt_(NULL
), got_plt_(NULL
), got_tlsdesc_(NULL
),
176 global_offset_table_(NULL
), rel_dyn_(NULL
),
177 copy_relocs_(elfcpp::R_386_COPY
), dynbss_(NULL
),
178 got_mod_index_offset_(-1U), tls_base_symbol_defined_(false)
181 // Process the relocations to determine unreferenced sections for
182 // garbage collection.
184 gc_process_relocs(Symbol_table
* symtab
,
186 Sized_relobj_file
<32, false>* object
,
187 unsigned int data_shndx
,
188 unsigned int sh_type
,
189 const unsigned char* prelocs
,
191 Output_section
* output_section
,
192 bool needs_special_offset_handling
,
193 size_t local_symbol_count
,
194 const unsigned char* plocal_symbols
);
196 // Scan the relocations to look for symbol adjustments.
198 scan_relocs(Symbol_table
* symtab
,
200 Sized_relobj_file
<32, false>* object
,
201 unsigned int data_shndx
,
202 unsigned int sh_type
,
203 const unsigned char* prelocs
,
205 Output_section
* output_section
,
206 bool needs_special_offset_handling
,
207 size_t local_symbol_count
,
208 const unsigned char* plocal_symbols
);
210 // Finalize the sections.
212 do_finalize_sections(Layout
*, const Input_objects
*, Symbol_table
*);
214 // Return the value to use for a dynamic which requires special
217 do_dynsym_value(const Symbol
*) const;
219 // Relocate a section.
221 relocate_section(const Relocate_info
<32, false>*,
222 unsigned int sh_type
,
223 const unsigned char* prelocs
,
225 Output_section
* output_section
,
226 bool needs_special_offset_handling
,
228 elfcpp::Elf_types
<32>::Elf_Addr view_address
,
229 section_size_type view_size
,
230 const Reloc_symbol_changes
*);
232 // Scan the relocs during a relocatable link.
234 scan_relocatable_relocs(Symbol_table
* symtab
,
236 Sized_relobj_file
<32, false>* object
,
237 unsigned int data_shndx
,
238 unsigned int sh_type
,
239 const unsigned char* prelocs
,
241 Output_section
* output_section
,
242 bool needs_special_offset_handling
,
243 size_t local_symbol_count
,
244 const unsigned char* plocal_symbols
,
245 Relocatable_relocs
*);
247 // Relocate a section during a relocatable link.
249 relocate_for_relocatable(const Relocate_info
<32, false>*,
250 unsigned int sh_type
,
251 const unsigned char* prelocs
,
253 Output_section
* output_section
,
254 off_t offset_in_output_section
,
255 const Relocatable_relocs
*,
257 elfcpp::Elf_types
<32>::Elf_Addr view_address
,
258 section_size_type view_size
,
259 unsigned char* reloc_view
,
260 section_size_type reloc_view_size
);
262 // Return a string used to fill a code section with nops.
264 do_code_fill(section_size_type length
) const;
266 // Return whether SYM is defined by the ABI.
268 do_is_defined_by_abi(const Symbol
* sym
) const
269 { return strcmp(sym
->name(), "___tls_get_addr") == 0; }
271 // Return whether a symbol name implies a local label. The UnixWare
272 // 2.1 cc generates temporary symbols that start with .X, so we
273 // recognize them here. FIXME: do other SVR4 compilers also use .X?.
274 // If so, we should move the .X recognition into
275 // Target::do_is_local_label_name.
277 do_is_local_label_name(const char* name
) const
279 if (name
[0] == '.' && name
[1] == 'X')
281 return Target::do_is_local_label_name(name
);
284 // Return the PLT section.
286 do_plt_section_for_global(const Symbol
*) const
287 { return this->plt_section(); }
290 do_plt_section_for_local(const Relobj
*, unsigned int) const
291 { return this->plt_section(); }
293 // We can tell whether we take the address of a function.
295 do_can_check_for_function_pointers() const
298 // Return the base for a DW_EH_PE_datarel encoding.
300 do_ehframe_datarel_base() const;
302 // Return whether SYM is call to a non-split function.
304 do_is_call_to_non_split(const Symbol
* sym
, unsigned int) const;
306 // Adjust -fsplit-stack code which calls non-split-stack code.
308 do_calls_non_split(Relobj
* object
, unsigned int shndx
,
309 section_offset_type fnoffset
, section_size_type fnsize
,
310 unsigned char* view
, section_size_type view_size
,
311 std::string
* from
, std::string
* to
) const;
313 // Return the size of the GOT section.
317 gold_assert(this->got_
!= NULL
);
318 return this->got_
->data_size();
321 // Return the number of entries in the GOT.
323 got_entry_count() const
325 if (this->got_
== NULL
)
327 return this->got_size() / 4;
330 // Return the number of entries in the PLT.
332 plt_entry_count() const;
334 // Return the offset of the first non-reserved PLT entry.
336 first_plt_entry_offset() const;
338 // Return the size of each PLT entry.
340 plt_entry_size() const;
343 // The class which scans relocations.
348 get_reference_flags(unsigned int r_type
);
351 local(Symbol_table
* symtab
, Layout
* layout
, Target_i386
* target
,
352 Sized_relobj_file
<32, false>* object
,
353 unsigned int data_shndx
,
354 Output_section
* output_section
,
355 const elfcpp::Rel
<32, false>& reloc
, unsigned int r_type
,
356 const elfcpp::Sym
<32, false>& lsym
);
359 global(Symbol_table
* symtab
, Layout
* layout
, Target_i386
* target
,
360 Sized_relobj_file
<32, false>* object
,
361 unsigned int data_shndx
,
362 Output_section
* output_section
,
363 const elfcpp::Rel
<32, false>& reloc
, unsigned int r_type
,
367 local_reloc_may_be_function_pointer(Symbol_table
* symtab
, Layout
* layout
,
369 Sized_relobj_file
<32, false>* object
,
370 unsigned int data_shndx
,
371 Output_section
* output_section
,
372 const elfcpp::Rel
<32, false>& reloc
,
374 const elfcpp::Sym
<32, false>& lsym
);
377 global_reloc_may_be_function_pointer(Symbol_table
* symtab
, Layout
* layout
,
379 Sized_relobj_file
<32, false>* object
,
380 unsigned int data_shndx
,
381 Output_section
* output_section
,
382 const elfcpp::Rel
<32, false>& reloc
,
387 possible_function_pointer_reloc(unsigned int r_type
);
390 reloc_needs_plt_for_ifunc(Sized_relobj_file
<32, false>*,
391 unsigned int r_type
);
394 unsupported_reloc_local(Sized_relobj_file
<32, false>*, unsigned int r_type
);
397 unsupported_reloc_global(Sized_relobj_file
<32, false>*, unsigned int r_type
,
401 // The class which implements relocation.
406 : skip_call_tls_get_addr_(false),
407 local_dynamic_type_(LOCAL_DYNAMIC_NONE
)
412 if (this->skip_call_tls_get_addr_
)
414 // FIXME: This needs to specify the location somehow.
415 gold_error(_("missing expected TLS relocation"));
419 // Return whether the static relocation needs to be applied.
421 should_apply_static_reloc(const Sized_symbol
<32>* gsym
,
424 Output_section
* output_section
);
426 // Do a relocation. Return false if the caller should not issue
427 // any warnings about this relocation.
429 relocate(const Relocate_info
<32, false>*, Target_i386
*, Output_section
*,
430 size_t relnum
, const elfcpp::Rel
<32, false>&,
431 unsigned int r_type
, const Sized_symbol
<32>*,
432 const Symbol_value
<32>*,
433 unsigned char*, elfcpp::Elf_types
<32>::Elf_Addr
,
437 // Do a TLS relocation.
439 relocate_tls(const Relocate_info
<32, false>*, Target_i386
* target
,
440 size_t relnum
, const elfcpp::Rel
<32, false>&,
441 unsigned int r_type
, const Sized_symbol
<32>*,
442 const Symbol_value
<32>*,
443 unsigned char*, elfcpp::Elf_types
<32>::Elf_Addr
,
446 // Do a TLS General-Dynamic to Initial-Exec transition.
448 tls_gd_to_ie(const Relocate_info
<32, false>*, size_t relnum
,
449 Output_segment
* tls_segment
,
450 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
451 elfcpp::Elf_types
<32>::Elf_Addr value
,
453 section_size_type view_size
);
455 // Do a TLS General-Dynamic to Local-Exec transition.
457 tls_gd_to_le(const Relocate_info
<32, false>*, size_t relnum
,
458 Output_segment
* tls_segment
,
459 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
460 elfcpp::Elf_types
<32>::Elf_Addr value
,
462 section_size_type view_size
);
464 // Do a TLS_GOTDESC or TLS_DESC_CALL General-Dynamic to Initial-Exec
467 tls_desc_gd_to_ie(const Relocate_info
<32, false>*, size_t relnum
,
468 Output_segment
* tls_segment
,
469 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
470 elfcpp::Elf_types
<32>::Elf_Addr value
,
472 section_size_type view_size
);
474 // Do a TLS_GOTDESC or TLS_DESC_CALL General-Dynamic to Local-Exec
477 tls_desc_gd_to_le(const Relocate_info
<32, false>*, size_t relnum
,
478 Output_segment
* tls_segment
,
479 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
480 elfcpp::Elf_types
<32>::Elf_Addr value
,
482 section_size_type view_size
);
484 // Do a TLS Local-Dynamic to Local-Exec transition.
486 tls_ld_to_le(const Relocate_info
<32, false>*, size_t relnum
,
487 Output_segment
* tls_segment
,
488 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
489 elfcpp::Elf_types
<32>::Elf_Addr value
,
491 section_size_type view_size
);
493 // Do a TLS Initial-Exec to Local-Exec transition.
495 tls_ie_to_le(const Relocate_info
<32, false>*, size_t relnum
,
496 Output_segment
* tls_segment
,
497 const elfcpp::Rel
<32, false>&, unsigned int r_type
,
498 elfcpp::Elf_types
<32>::Elf_Addr value
,
500 section_size_type view_size
);
502 // We need to keep track of which type of local dynamic relocation
503 // we have seen, so that we can optimize R_386_TLS_LDO_32 correctly.
504 enum Local_dynamic_type
511 // This is set if we should skip the next reloc, which should be a
512 // PLT32 reloc against ___tls_get_addr.
513 bool skip_call_tls_get_addr_
;
514 // The type of local dynamic relocation we have seen in the section
515 // being relocated, if any.
516 Local_dynamic_type local_dynamic_type_
;
519 // A class which returns the size required for a relocation type,
520 // used while scanning relocs during a relocatable link.
521 class Relocatable_size_for_reloc
525 get_size_for_reloc(unsigned int, Relobj
*);
528 // Adjust TLS relocation type based on the options and whether this
529 // is a local symbol.
530 static tls::Tls_optimization
531 optimize_tls_reloc(bool is_final
, int r_type
);
533 // Get the GOT section, creating it if necessary.
534 Output_data_got
<32, false>*
535 got_section(Symbol_table
*, Layout
*);
537 // Get the GOT PLT section.
539 got_plt_section() const
541 gold_assert(this->got_plt_
!= NULL
);
542 return this->got_plt_
;
545 // Get the GOT section for TLSDESC entries.
546 Output_data_got
<32, false>*
547 got_tlsdesc_section() const
549 gold_assert(this->got_tlsdesc_
!= NULL
);
550 return this->got_tlsdesc_
;
553 // Create the PLT section.
555 make_plt_section(Symbol_table
* symtab
, Layout
* layout
);
557 // Create a PLT entry for a global symbol.
559 make_plt_entry(Symbol_table
*, Layout
*, Symbol
*);
561 // Create a PLT entry for a local STT_GNU_IFUNC symbol.
563 make_local_ifunc_plt_entry(Symbol_table
*, Layout
*,
564 Sized_relobj_file
<32, false>* relobj
,
565 unsigned int local_sym_index
);
567 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
569 define_tls_base_symbol(Symbol_table
*, Layout
*);
571 // Create a GOT entry for the TLS module index.
573 got_mod_index_entry(Symbol_table
* symtab
, Layout
* layout
,
574 Sized_relobj_file
<32, false>* object
);
576 // Get the PLT section.
577 Output_data_plt_i386
*
580 gold_assert(this->plt_
!= NULL
);
584 // Get the dynamic reloc section, creating it if necessary.
586 rel_dyn_section(Layout
*);
588 // Get the section to use for TLS_DESC relocations.
590 rel_tls_desc_section(Layout
*) const;
592 // Add a potential copy relocation.
594 copy_reloc(Symbol_table
* symtab
, Layout
* layout
,
595 Sized_relobj_file
<32, false>* object
,
596 unsigned int shndx
, Output_section
* output_section
,
597 Symbol
* sym
, const elfcpp::Rel
<32, false>& reloc
)
599 this->copy_relocs_
.copy_reloc(symtab
, layout
,
600 symtab
->get_sized_symbol
<32>(sym
),
601 object
, shndx
, output_section
, reloc
,
602 this->rel_dyn_section(layout
));
605 // Information about this specific target which we pass to the
606 // general Target structure.
607 static const Target::Target_info i386_info
;
609 // The types of GOT entries needed for this platform.
610 // These values are exposed to the ABI in an incremental link.
611 // Do not renumber existing values without changing the version
612 // number of the .gnu_incremental_inputs section.
615 GOT_TYPE_STANDARD
= 0, // GOT entry for a regular symbol
616 GOT_TYPE_TLS_NOFFSET
= 1, // GOT entry for negative TLS offset
617 GOT_TYPE_TLS_OFFSET
= 2, // GOT entry for positive TLS offset
618 GOT_TYPE_TLS_PAIR
= 3, // GOT entry for TLS module/offset pair
619 GOT_TYPE_TLS_DESC
= 4 // GOT entry for TLS_DESC pair
623 Output_data_got
<32, false>* got_
;
625 Output_data_plt_i386
* plt_
;
626 // The GOT PLT section.
627 Output_data_space
* got_plt_
;
628 // The GOT section for TLSDESC relocations.
629 Output_data_got
<32, false>* got_tlsdesc_
;
630 // The _GLOBAL_OFFSET_TABLE_ symbol.
631 Symbol
* global_offset_table_
;
632 // The dynamic reloc section.
633 Reloc_section
* rel_dyn_
;
634 // Relocs saved to avoid a COPY reloc.
635 Copy_relocs
<elfcpp::SHT_REL
, 32, false> copy_relocs_
;
636 // Space for variables copied with a COPY reloc.
637 Output_data_space
* dynbss_
;
638 // Offset of the GOT entry for the TLS module index.
639 unsigned int got_mod_index_offset_
;
640 // True if the _TLS_MODULE_BASE_ symbol has been defined.
641 bool tls_base_symbol_defined_
;
644 const Target::Target_info
Target_i386::i386_info
=
647 false, // is_big_endian
648 elfcpp::EM_386
, // machine_code
649 false, // has_make_symbol
650 false, // has_resolve
651 true, // has_code_fill
652 true, // is_default_stack_executable
653 true, // can_icf_inline_merge_sections
655 "/usr/lib/libc.so.1", // dynamic_linker
656 0x08048000, // default_text_segment_address
657 0x1000, // abi_pagesize (overridable by -z max-page-size)
658 0x1000, // common_pagesize (overridable by -z common-page-size)
659 elfcpp::SHN_UNDEF
, // small_common_shndx
660 elfcpp::SHN_UNDEF
, // large_common_shndx
661 0, // small_common_section_flags
662 0, // large_common_section_flags
663 NULL
, // attributes_section
664 NULL
// attributes_vendor
667 // Get the GOT section, creating it if necessary.
669 Output_data_got
<32, false>*
670 Target_i386::got_section(Symbol_table
* symtab
, Layout
* layout
)
672 if (this->got_
== NULL
)
674 gold_assert(symtab
!= NULL
&& layout
!= NULL
);
676 this->got_
= new Output_data_got
<32, false>();
678 layout
->add_output_section_data(".got", elfcpp::SHT_PROGBITS
,
680 | elfcpp::SHF_WRITE
),
681 this->got_
, ORDER_RELRO_LAST
, true);
683 this->got_plt_
= new Output_data_space(4, "** GOT PLT");
684 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
686 | elfcpp::SHF_WRITE
),
687 this->got_plt_
, ORDER_NON_RELRO_FIRST
,
690 // The first three entries are reserved.
691 this->got_plt_
->set_current_data_size(3 * 4);
693 // Those bytes can go into the relro segment.
694 layout
->increase_relro(3 * 4);
696 // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
697 this->global_offset_table_
=
698 symtab
->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL
,
699 Symbol_table::PREDEFINED
,
701 0, 0, elfcpp::STT_OBJECT
,
703 elfcpp::STV_HIDDEN
, 0,
706 // If there are any TLSDESC relocations, they get GOT entries in
707 // .got.plt after the jump slot entries.
708 this->got_tlsdesc_
= new Output_data_got
<32, false>();
709 layout
->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS
,
711 | elfcpp::SHF_WRITE
),
713 ORDER_NON_RELRO_FIRST
, false);
719 // Get the dynamic reloc section, creating it if necessary.
721 Target_i386::Reloc_section
*
722 Target_i386::rel_dyn_section(Layout
* layout
)
724 if (this->rel_dyn_
== NULL
)
726 gold_assert(layout
!= NULL
);
727 this->rel_dyn_
= new Reloc_section(parameters
->options().combreloc());
728 layout
->add_output_section_data(".rel.dyn", elfcpp::SHT_REL
,
729 elfcpp::SHF_ALLOC
, this->rel_dyn_
,
730 ORDER_DYNAMIC_RELOCS
, false);
732 return this->rel_dyn_
;
735 // Create the PLT section. The ordinary .got section is an argument,
736 // since we need to refer to the start. We also create our own .got
737 // section just for PLT entries.
739 Output_data_plt_i386::Output_data_plt_i386(Symbol_table
* symtab
,
741 Output_data_space
* got_plt
)
742 : Output_section_data(16), tls_desc_rel_(NULL
), got_plt_(got_plt
), count_(0),
743 global_ifuncs_(), local_ifuncs_()
745 this->rel_
= new Reloc_section(false);
746 layout
->add_output_section_data(".rel.plt", elfcpp::SHT_REL
,
747 elfcpp::SHF_ALLOC
, this->rel_
,
748 ORDER_DYNAMIC_PLT_RELOCS
, false);
750 if (parameters
->doing_static_link())
752 // A statically linked executable will only have a .rel.plt
753 // section to hold R_386_IRELATIVE relocs for STT_GNU_IFUNC
754 // symbols. The library will use these symbols to locate the
755 // IRELATIVE relocs at program startup time.
756 symtab
->define_in_output_data("__rel_iplt_start", NULL
,
757 Symbol_table::PREDEFINED
,
758 this->rel_
, 0, 0, elfcpp::STT_NOTYPE
,
759 elfcpp::STB_GLOBAL
, elfcpp::STV_HIDDEN
,
761 symtab
->define_in_output_data("__rel_iplt_end", NULL
,
762 Symbol_table::PREDEFINED
,
763 this->rel_
, 0, 0, elfcpp::STT_NOTYPE
,
764 elfcpp::STB_GLOBAL
, elfcpp::STV_HIDDEN
,
768 // Add unwind information if requested.
769 if (parameters
->options().ld_generated_unwind_info())
770 layout
->add_eh_frame_for_plt(this, plt_eh_frame_cie
, plt_eh_frame_cie_size
,
771 plt_eh_frame_fde
, plt_eh_frame_fde_size
);
775 Output_data_plt_i386::do_adjust_output_section(Output_section
* os
)
777 // UnixWare sets the entsize of .plt to 4, and so does the old GNU
778 // linker, and so do we.
782 // Add an entry to the PLT.
785 Output_data_plt_i386::add_entry(Symbol
* gsym
)
787 gold_assert(!gsym
->has_plt_offset());
789 // Note that when setting the PLT offset we skip the initial
790 // reserved PLT entry.
791 gsym
->set_plt_offset((this->count_
+ 1) * plt_entry_size
);
795 section_offset_type got_offset
= this->got_plt_
->current_data_size();
797 // Every PLT entry needs a GOT entry which points back to the PLT
798 // entry (this will be changed by the dynamic linker, normally
799 // lazily when the function is called).
800 this->got_plt_
->set_current_data_size(got_offset
+ 4);
802 // Every PLT entry needs a reloc.
803 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
804 && gsym
->can_use_relative_reloc(false))
806 this->rel_
->add_symbolless_global_addend(gsym
, elfcpp::R_386_IRELATIVE
,
807 this->got_plt_
, got_offset
);
808 struct Global_ifunc gi
;
810 gi
.got_offset
= got_offset
;
811 this->global_ifuncs_
.push_back(gi
);
815 gsym
->set_needs_dynsym_entry();
816 this->rel_
->add_global(gsym
, elfcpp::R_386_JUMP_SLOT
, this->got_plt_
,
820 // Note that we don't need to save the symbol. The contents of the
821 // PLT are independent of which symbols are used. The symbols only
822 // appear in the relocations.
825 // Add an entry to the PLT for a local STT_GNU_IFUNC symbol. Return
829 Output_data_plt_i386::add_local_ifunc_entry(
830 Sized_relobj_file
<32, false>* relobj
,
831 unsigned int local_sym_index
)
833 unsigned int plt_offset
= (this->count_
+ 1) * plt_entry_size
;
836 section_offset_type got_offset
= this->got_plt_
->current_data_size();
838 // Every PLT entry needs a GOT entry which points back to the PLT
840 this->got_plt_
->set_current_data_size(got_offset
+ 4);
842 // Every PLT entry needs a reloc.
843 this->rel_
->add_symbolless_local_addend(relobj
, local_sym_index
,
844 elfcpp::R_386_IRELATIVE
,
845 this->got_plt_
, got_offset
);
847 struct Local_ifunc li
;
849 li
.local_sym_index
= local_sym_index
;
850 li
.got_offset
= got_offset
;
851 this->local_ifuncs_
.push_back(li
);
856 // Return where the TLS_DESC relocations should go, creating it if
857 // necessary. These follow the JUMP_SLOT relocations.
859 Output_data_plt_i386::Reloc_section
*
860 Output_data_plt_i386::rel_tls_desc(Layout
* layout
)
862 if (this->tls_desc_rel_
== NULL
)
864 this->tls_desc_rel_
= new Reloc_section(false);
865 layout
->add_output_section_data(".rel.plt", elfcpp::SHT_REL
,
866 elfcpp::SHF_ALLOC
, this->tls_desc_rel_
,
867 ORDER_DYNAMIC_PLT_RELOCS
, false);
868 gold_assert(this->tls_desc_rel_
->output_section() ==
869 this->rel_
->output_section());
871 return this->tls_desc_rel_
;
874 // The first entry in the PLT for an executable.
876 const unsigned char Output_data_plt_i386::exec_first_plt_entry
[plt_entry_size
] =
878 0xff, 0x35, // pushl contents of memory address
879 0, 0, 0, 0, // replaced with address of .got + 4
880 0xff, 0x25, // jmp indirect
881 0, 0, 0, 0, // replaced with address of .got + 8
885 // The first entry in the PLT for a shared object.
887 const unsigned char Output_data_plt_i386::dyn_first_plt_entry
[plt_entry_size
] =
889 0xff, 0xb3, 4, 0, 0, 0, // pushl 4(%ebx)
890 0xff, 0xa3, 8, 0, 0, 0, // jmp *8(%ebx)
894 // Subsequent entries in the PLT for an executable.
896 const unsigned char Output_data_plt_i386::exec_plt_entry
[plt_entry_size
] =
898 0xff, 0x25, // jmp indirect
899 0, 0, 0, 0, // replaced with address of symbol in .got
900 0x68, // pushl immediate
901 0, 0, 0, 0, // replaced with offset into relocation table
902 0xe9, // jmp relative
903 0, 0, 0, 0 // replaced with offset to start of .plt
906 // Subsequent entries in the PLT for a shared object.
908 const unsigned char Output_data_plt_i386::dyn_plt_entry
[plt_entry_size
] =
910 0xff, 0xa3, // jmp *offset(%ebx)
911 0, 0, 0, 0, // replaced with offset of symbol in .got
912 0x68, // pushl immediate
913 0, 0, 0, 0, // replaced with offset into relocation table
914 0xe9, // jmp relative
915 0, 0, 0, 0 // replaced with offset to start of .plt
918 // The .eh_frame unwind information for the PLT.
921 Output_data_plt_i386::plt_eh_frame_cie
[plt_eh_frame_cie_size
] =
924 'z', // Augmentation: augmentation size included.
925 'R', // Augmentation: FDE encoding included.
926 '\0', // End of augmentation string.
927 1, // Code alignment factor.
928 0x7c, // Data alignment factor.
929 8, // Return address column.
930 1, // Augmentation size.
931 (elfcpp::DW_EH_PE_pcrel
// FDE encoding.
932 | elfcpp::DW_EH_PE_sdata4
),
933 elfcpp::DW_CFA_def_cfa
, 4, 4, // DW_CFA_def_cfa: r4 (esp) ofs 4.
934 elfcpp::DW_CFA_offset
+ 8, 1, // DW_CFA_offset: r8 (eip) at cfa-4.
935 elfcpp::DW_CFA_nop
, // Align to 16 bytes.
940 Output_data_plt_i386::plt_eh_frame_fde
[plt_eh_frame_fde_size
] =
942 0, 0, 0, 0, // Replaced with offset to .plt.
943 0, 0, 0, 0, // Replaced with size of .plt.
944 0, // Augmentation size.
945 elfcpp::DW_CFA_def_cfa_offset
, 8, // DW_CFA_def_cfa_offset: 8.
946 elfcpp::DW_CFA_advance_loc
+ 6, // Advance 6 to __PLT__ + 6.
947 elfcpp::DW_CFA_def_cfa_offset
, 12, // DW_CFA_def_cfa_offset: 12.
948 elfcpp::DW_CFA_advance_loc
+ 10, // Advance 10 to __PLT__ + 16.
949 elfcpp::DW_CFA_def_cfa_expression
, // DW_CFA_def_cfa_expression.
951 elfcpp::DW_OP_breg4
, 4, // Push %esp + 4.
952 elfcpp::DW_OP_breg8
, 0, // Push %eip.
953 elfcpp::DW_OP_lit15
, // Push 0xf.
954 elfcpp::DW_OP_and
, // & (%eip & 0xf).
955 elfcpp::DW_OP_lit11
, // Push 0xb.
956 elfcpp::DW_OP_ge
, // >= ((%eip & 0xf) >= 0xb)
957 elfcpp::DW_OP_lit2
, // Push 2.
958 elfcpp::DW_OP_shl
, // << (((%eip & 0xf) >= 0xb) << 2)
959 elfcpp::DW_OP_plus
, // + ((((%eip&0xf)>=0xb)<<2)+%esp+4
960 elfcpp::DW_CFA_nop
, // Align to 32 bytes.
966 // Write out the PLT. This uses the hand-coded instructions above,
967 // and adjusts them as needed. This is all specified by the i386 ELF
968 // Processor Supplement.
971 Output_data_plt_i386::do_write(Output_file
* of
)
973 const off_t offset
= this->offset();
974 const section_size_type oview_size
=
975 convert_to_section_size_type(this->data_size());
976 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
978 const off_t got_file_offset
= this->got_plt_
->offset();
979 const section_size_type got_size
=
980 convert_to_section_size_type(this->got_plt_
->data_size());
981 unsigned char* const got_view
= of
->get_output_view(got_file_offset
,
984 unsigned char* pov
= oview
;
986 elfcpp::Elf_types
<32>::Elf_Addr plt_address
= this->address();
987 elfcpp::Elf_types
<32>::Elf_Addr got_address
= this->got_plt_
->address();
989 if (parameters
->options().output_is_position_independent())
990 memcpy(pov
, dyn_first_plt_entry
, plt_entry_size
);
993 memcpy(pov
, exec_first_plt_entry
, plt_entry_size
);
994 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2, got_address
+ 4);
995 elfcpp::Swap
<32, false>::writeval(pov
+ 8, got_address
+ 8);
997 pov
+= plt_entry_size
;
999 unsigned char* got_pov
= got_view
;
1001 memset(got_pov
, 0, 12);
1004 const int rel_size
= elfcpp::Elf_sizes
<32>::rel_size
;
1006 unsigned int plt_offset
= plt_entry_size
;
1007 unsigned int plt_rel_offset
= 0;
1008 unsigned int got_offset
= 12;
1009 const unsigned int count
= this->count_
;
1010 for (unsigned int i
= 0;
1013 pov
+= plt_entry_size
,
1015 plt_offset
+= plt_entry_size
,
1016 plt_rel_offset
+= rel_size
,
1019 // Set and adjust the PLT entry itself.
1021 if (parameters
->options().output_is_position_independent())
1023 memcpy(pov
, dyn_plt_entry
, plt_entry_size
);
1024 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2, got_offset
);
1028 memcpy(pov
, exec_plt_entry
, plt_entry_size
);
1029 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 2,
1034 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 7, plt_rel_offset
);
1035 elfcpp::Swap
<32, false>::writeval(pov
+ 12,
1036 - (plt_offset
+ plt_entry_size
));
1038 // Set the entry in the GOT.
1039 elfcpp::Swap
<32, false>::writeval(got_pov
, plt_address
+ plt_offset
+ 6);
1042 // If any STT_GNU_IFUNC symbols have PLT entries, we need to change
1043 // the GOT to point to the actual symbol value, rather than point to
1044 // the PLT entry. That will let the dynamic linker call the right
1045 // function when resolving IRELATIVE relocations.
1046 for (std::vector
<Global_ifunc
>::const_iterator p
=
1047 this->global_ifuncs_
.begin();
1048 p
!= this->global_ifuncs_
.end();
1051 const Sized_symbol
<32>* ssym
=
1052 static_cast<const Sized_symbol
<32>*>(p
->sym
);
1053 elfcpp::Swap
<32, false>::writeval(got_view
+ p
->got_offset
,
1057 for (std::vector
<Local_ifunc
>::const_iterator p
=
1058 this->local_ifuncs_
.begin();
1059 p
!= this->local_ifuncs_
.end();
1062 const Symbol_value
<32>* psymval
=
1063 p
->object
->local_symbol(p
->local_sym_index
);
1064 elfcpp::Swap
<32, false>::writeval(got_view
+ p
->got_offset
,
1065 psymval
->value(p
->object
, 0));
1068 gold_assert(static_cast<section_size_type
>(pov
- oview
) == oview_size
);
1069 gold_assert(static_cast<section_size_type
>(got_pov
- got_view
) == got_size
);
1071 of
->write_output_view(offset
, oview_size
, oview
);
1072 of
->write_output_view(got_file_offset
, got_size
, got_view
);
1075 // Create the PLT section.
1078 Target_i386::make_plt_section(Symbol_table
* symtab
, Layout
* layout
)
1080 if (this->plt_
== NULL
)
1082 // Create the GOT sections first.
1083 this->got_section(symtab
, layout
);
1085 this->plt_
= new Output_data_plt_i386(symtab
, layout
, this->got_plt_
);
1086 layout
->add_output_section_data(".plt", elfcpp::SHT_PROGBITS
,
1088 | elfcpp::SHF_EXECINSTR
),
1089 this->plt_
, ORDER_PLT
, false);
1091 // Make the sh_info field of .rel.plt point to .plt.
1092 Output_section
* rel_plt_os
= this->plt_
->rel_plt()->output_section();
1093 rel_plt_os
->set_info_section(this->plt_
->output_section());
1097 // Create a PLT entry for a global symbol.
1100 Target_i386::make_plt_entry(Symbol_table
* symtab
, Layout
* layout
, Symbol
* gsym
)
1102 if (gsym
->has_plt_offset())
1104 if (this->plt_
== NULL
)
1105 this->make_plt_section(symtab
, layout
);
1106 this->plt_
->add_entry(gsym
);
1109 // Make a PLT entry for a local STT_GNU_IFUNC symbol.
1112 Target_i386::make_local_ifunc_plt_entry(Symbol_table
* symtab
, Layout
* layout
,
1113 Sized_relobj_file
<32, false>* relobj
,
1114 unsigned int local_sym_index
)
1116 if (relobj
->local_has_plt_offset(local_sym_index
))
1118 if (this->plt_
== NULL
)
1119 this->make_plt_section(symtab
, layout
);
1120 unsigned int plt_offset
= this->plt_
->add_local_ifunc_entry(relobj
,
1122 relobj
->set_local_plt_offset(local_sym_index
, plt_offset
);
1125 // Return the number of entries in the PLT.
1128 Target_i386::plt_entry_count() const
1130 if (this->plt_
== NULL
)
1132 return this->plt_
->entry_count();
1135 // Return the offset of the first non-reserved PLT entry.
1138 Target_i386::first_plt_entry_offset() const
1140 return Output_data_plt_i386::first_plt_entry_offset();
1143 // Return the size of each PLT entry.
1146 Target_i386::plt_entry_size() const
1148 return Output_data_plt_i386::get_plt_entry_size();
1151 // Get the section to use for TLS_DESC relocations.
1153 Target_i386::Reloc_section
*
1154 Target_i386::rel_tls_desc_section(Layout
* layout
) const
1156 return this->plt_section()->rel_tls_desc(layout
);
1159 // Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
1162 Target_i386::define_tls_base_symbol(Symbol_table
* symtab
, Layout
* layout
)
1164 if (this->tls_base_symbol_defined_
)
1167 Output_segment
* tls_segment
= layout
->tls_segment();
1168 if (tls_segment
!= NULL
)
1170 bool is_exec
= parameters
->options().output_is_executable();
1171 symtab
->define_in_output_segment("_TLS_MODULE_BASE_", NULL
,
1172 Symbol_table::PREDEFINED
,
1176 elfcpp::STV_HIDDEN
, 0,
1178 ? Symbol::SEGMENT_END
1179 : Symbol::SEGMENT_START
),
1182 this->tls_base_symbol_defined_
= true;
1185 // Create a GOT entry for the TLS module index.
1188 Target_i386::got_mod_index_entry(Symbol_table
* symtab
, Layout
* layout
,
1189 Sized_relobj_file
<32, false>* object
)
1191 if (this->got_mod_index_offset_
== -1U)
1193 gold_assert(symtab
!= NULL
&& layout
!= NULL
&& object
!= NULL
);
1194 Reloc_section
* rel_dyn
= this->rel_dyn_section(layout
);
1195 Output_data_got
<32, false>* got
= this->got_section(symtab
, layout
);
1196 unsigned int got_offset
= got
->add_constant(0);
1197 rel_dyn
->add_local(object
, 0, elfcpp::R_386_TLS_DTPMOD32
, got
,
1199 got
->add_constant(0);
1200 this->got_mod_index_offset_
= got_offset
;
1202 return this->got_mod_index_offset_
;
1205 // Optimize the TLS relocation type based on what we know about the
1206 // symbol. IS_FINAL is true if the final address of this symbol is
1207 // known at link time.
1209 tls::Tls_optimization
1210 Target_i386::optimize_tls_reloc(bool is_final
, int r_type
)
1212 // If we are generating a shared library, then we can't do anything
1214 if (parameters
->options().shared())
1215 return tls::TLSOPT_NONE
;
1219 case elfcpp::R_386_TLS_GD
:
1220 case elfcpp::R_386_TLS_GOTDESC
:
1221 case elfcpp::R_386_TLS_DESC_CALL
:
1222 // These are General-Dynamic which permits fully general TLS
1223 // access. Since we know that we are generating an executable,
1224 // we can convert this to Initial-Exec. If we also know that
1225 // this is a local symbol, we can further switch to Local-Exec.
1227 return tls::TLSOPT_TO_LE
;
1228 return tls::TLSOPT_TO_IE
;
1230 case elfcpp::R_386_TLS_LDM
:
1231 // This is Local-Dynamic, which refers to a local symbol in the
1232 // dynamic TLS block. Since we know that we generating an
1233 // executable, we can switch to Local-Exec.
1234 return tls::TLSOPT_TO_LE
;
1236 case elfcpp::R_386_TLS_LDO_32
:
1237 // Another type of Local-Dynamic relocation.
1238 return tls::TLSOPT_TO_LE
;
1240 case elfcpp::R_386_TLS_IE
:
1241 case elfcpp::R_386_TLS_GOTIE
:
1242 case elfcpp::R_386_TLS_IE_32
:
1243 // These are Initial-Exec relocs which get the thread offset
1244 // from the GOT. If we know that we are linking against the
1245 // local symbol, we can switch to Local-Exec, which links the
1246 // thread offset into the instruction.
1248 return tls::TLSOPT_TO_LE
;
1249 return tls::TLSOPT_NONE
;
1251 case elfcpp::R_386_TLS_LE
:
1252 case elfcpp::R_386_TLS_LE_32
:
1253 // When we already have Local-Exec, there is nothing further we
1255 return tls::TLSOPT_NONE
;
1262 // Get the Reference_flags for a particular relocation.
1265 Target_i386::Scan::get_reference_flags(unsigned int r_type
)
1269 case elfcpp::R_386_NONE
:
1270 case elfcpp::R_386_GNU_VTINHERIT
:
1271 case elfcpp::R_386_GNU_VTENTRY
:
1272 case elfcpp::R_386_GOTPC
:
1273 // No symbol reference.
1276 case elfcpp::R_386_32
:
1277 case elfcpp::R_386_16
:
1278 case elfcpp::R_386_8
:
1279 return Symbol::ABSOLUTE_REF
;
1281 case elfcpp::R_386_PC32
:
1282 case elfcpp::R_386_PC16
:
1283 case elfcpp::R_386_PC8
:
1284 case elfcpp::R_386_GOTOFF
:
1285 return Symbol::RELATIVE_REF
;
1287 case elfcpp::R_386_PLT32
:
1288 return Symbol::FUNCTION_CALL
| Symbol::RELATIVE_REF
;
1290 case elfcpp::R_386_GOT32
:
1292 return Symbol::ABSOLUTE_REF
;
1294 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1295 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
1296 case elfcpp::R_386_TLS_DESC_CALL
:
1297 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1298 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1299 case elfcpp::R_386_TLS_IE
: // Initial-exec
1300 case elfcpp::R_386_TLS_IE_32
:
1301 case elfcpp::R_386_TLS_GOTIE
:
1302 case elfcpp::R_386_TLS_LE
: // Local-exec
1303 case elfcpp::R_386_TLS_LE_32
:
1304 return Symbol::TLS_REF
;
1306 case elfcpp::R_386_COPY
:
1307 case elfcpp::R_386_GLOB_DAT
:
1308 case elfcpp::R_386_JUMP_SLOT
:
1309 case elfcpp::R_386_RELATIVE
:
1310 case elfcpp::R_386_IRELATIVE
:
1311 case elfcpp::R_386_TLS_TPOFF
:
1312 case elfcpp::R_386_TLS_DTPMOD32
:
1313 case elfcpp::R_386_TLS_DTPOFF32
:
1314 case elfcpp::R_386_TLS_TPOFF32
:
1315 case elfcpp::R_386_TLS_DESC
:
1316 case elfcpp::R_386_32PLT
:
1317 case elfcpp::R_386_TLS_GD_32
:
1318 case elfcpp::R_386_TLS_GD_PUSH
:
1319 case elfcpp::R_386_TLS_GD_CALL
:
1320 case elfcpp::R_386_TLS_GD_POP
:
1321 case elfcpp::R_386_TLS_LDM_32
:
1322 case elfcpp::R_386_TLS_LDM_PUSH
:
1323 case elfcpp::R_386_TLS_LDM_CALL
:
1324 case elfcpp::R_386_TLS_LDM_POP
:
1325 case elfcpp::R_386_USED_BY_INTEL_200
:
1327 // Not expected. We will give an error later.
1332 // Report an unsupported relocation against a local symbol.
1335 Target_i386::Scan::unsupported_reloc_local(Sized_relobj_file
<32, false>* object
,
1336 unsigned int r_type
)
1338 gold_error(_("%s: unsupported reloc %u against local symbol"),
1339 object
->name().c_str(), r_type
);
1342 // Return whether we need to make a PLT entry for a relocation of a
1343 // given type against a STT_GNU_IFUNC symbol.
1346 Target_i386::Scan::reloc_needs_plt_for_ifunc(
1347 Sized_relobj_file
<32, false>* object
,
1348 unsigned int r_type
)
1350 int flags
= Scan::get_reference_flags(r_type
);
1351 if (flags
& Symbol::TLS_REF
)
1352 gold_error(_("%s: unsupported TLS reloc %u for IFUNC symbol"),
1353 object
->name().c_str(), r_type
);
1357 // Scan a relocation for a local symbol.
1360 Target_i386::Scan::local(Symbol_table
* symtab
,
1362 Target_i386
* target
,
1363 Sized_relobj_file
<32, false>* object
,
1364 unsigned int data_shndx
,
1365 Output_section
* output_section
,
1366 const elfcpp::Rel
<32, false>& reloc
,
1367 unsigned int r_type
,
1368 const elfcpp::Sym
<32, false>& lsym
)
1370 // A local STT_GNU_IFUNC symbol may require a PLT entry.
1371 if (lsym
.get_st_type() == elfcpp::STT_GNU_IFUNC
1372 && this->reloc_needs_plt_for_ifunc(object
, r_type
))
1374 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1375 target
->make_local_ifunc_plt_entry(symtab
, layout
, object
, r_sym
);
1380 case elfcpp::R_386_NONE
:
1381 case elfcpp::R_386_GNU_VTINHERIT
:
1382 case elfcpp::R_386_GNU_VTENTRY
:
1385 case elfcpp::R_386_32
:
1386 // If building a shared library (or a position-independent
1387 // executable), we need to create a dynamic relocation for
1388 // this location. The relocation applied at link time will
1389 // apply the link-time value, so we flag the location with
1390 // an R_386_RELATIVE relocation so the dynamic loader can
1391 // relocate it easily.
1392 if (parameters
->options().output_is_position_independent())
1394 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1395 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1396 rel_dyn
->add_local_relative(object
, r_sym
, elfcpp::R_386_RELATIVE
,
1397 output_section
, data_shndx
,
1398 reloc
.get_r_offset());
1402 case elfcpp::R_386_16
:
1403 case elfcpp::R_386_8
:
1404 // If building a shared library (or a position-independent
1405 // executable), we need to create a dynamic relocation for
1406 // this location. Because the addend needs to remain in the
1407 // data section, we need to be careful not to apply this
1408 // relocation statically.
1409 if (parameters
->options().output_is_position_independent())
1411 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1412 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1413 if (lsym
.get_st_type() != elfcpp::STT_SECTION
)
1414 rel_dyn
->add_local(object
, r_sym
, r_type
, output_section
,
1415 data_shndx
, reloc
.get_r_offset());
1418 gold_assert(lsym
.get_st_value() == 0);
1419 unsigned int shndx
= lsym
.get_st_shndx();
1421 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
,
1424 object
->error(_("section symbol %u has bad shndx %u"),
1427 rel_dyn
->add_local_section(object
, shndx
,
1428 r_type
, output_section
,
1429 data_shndx
, reloc
.get_r_offset());
1434 case elfcpp::R_386_PC32
:
1435 case elfcpp::R_386_PC16
:
1436 case elfcpp::R_386_PC8
:
1439 case elfcpp::R_386_PLT32
:
1440 // Since we know this is a local symbol, we can handle this as a
1444 case elfcpp::R_386_GOTOFF
:
1445 case elfcpp::R_386_GOTPC
:
1446 // We need a GOT section.
1447 target
->got_section(symtab
, layout
);
1450 case elfcpp::R_386_GOT32
:
1452 // The symbol requires a GOT entry.
1453 Output_data_got
<32, false>* got
= target
->got_section(symtab
, layout
);
1454 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1456 // For a STT_GNU_IFUNC symbol we want the PLT offset. That
1457 // lets function pointers compare correctly with shared
1458 // libraries. Otherwise we would need an IRELATIVE reloc.
1460 if (lsym
.get_st_type() == elfcpp::STT_GNU_IFUNC
)
1461 is_new
= got
->add_local_plt(object
, r_sym
, GOT_TYPE_STANDARD
);
1463 is_new
= got
->add_local(object
, r_sym
, GOT_TYPE_STANDARD
);
1466 // If we are generating a shared object, we need to add a
1467 // dynamic RELATIVE relocation for this symbol's GOT entry.
1468 if (parameters
->options().output_is_position_independent())
1470 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1471 unsigned int got_offset
=
1472 object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
);
1473 rel_dyn
->add_local_relative(object
, r_sym
,
1474 elfcpp::R_386_RELATIVE
,
1481 // These are relocations which should only be seen by the
1482 // dynamic linker, and should never be seen here.
1483 case elfcpp::R_386_COPY
:
1484 case elfcpp::R_386_GLOB_DAT
:
1485 case elfcpp::R_386_JUMP_SLOT
:
1486 case elfcpp::R_386_RELATIVE
:
1487 case elfcpp::R_386_IRELATIVE
:
1488 case elfcpp::R_386_TLS_TPOFF
:
1489 case elfcpp::R_386_TLS_DTPMOD32
:
1490 case elfcpp::R_386_TLS_DTPOFF32
:
1491 case elfcpp::R_386_TLS_TPOFF32
:
1492 case elfcpp::R_386_TLS_DESC
:
1493 gold_error(_("%s: unexpected reloc %u in object file"),
1494 object
->name().c_str(), r_type
);
1497 // These are initial TLS relocs, which are expected when
1499 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1500 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
1501 case elfcpp::R_386_TLS_DESC_CALL
:
1502 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1503 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1504 case elfcpp::R_386_TLS_IE
: // Initial-exec
1505 case elfcpp::R_386_TLS_IE_32
:
1506 case elfcpp::R_386_TLS_GOTIE
:
1507 case elfcpp::R_386_TLS_LE
: // Local-exec
1508 case elfcpp::R_386_TLS_LE_32
:
1510 bool output_is_shared
= parameters
->options().shared();
1511 const tls::Tls_optimization optimized_type
1512 = Target_i386::optimize_tls_reloc(!output_is_shared
, r_type
);
1515 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1516 if (optimized_type
== tls::TLSOPT_NONE
)
1518 // Create a pair of GOT entries for the module index and
1519 // dtv-relative offset.
1520 Output_data_got
<32, false>* got
1521 = target
->got_section(symtab
, layout
);
1522 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1523 unsigned int shndx
= lsym
.get_st_shndx();
1525 shndx
= object
->adjust_sym_shndx(r_sym
, shndx
, &is_ordinary
);
1527 object
->error(_("local symbol %u has bad shndx %u"),
1530 got
->add_local_pair_with_rel(object
, r_sym
, shndx
,
1532 target
->rel_dyn_section(layout
),
1533 elfcpp::R_386_TLS_DTPMOD32
, 0);
1535 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1536 unsupported_reloc_local(object
, r_type
);
1539 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva)
1540 target
->define_tls_base_symbol(symtab
, layout
);
1541 if (optimized_type
== tls::TLSOPT_NONE
)
1543 // Create a double GOT entry with an R_386_TLS_DESC
1544 // reloc. The R_386_TLS_DESC reloc is resolved
1545 // lazily, so the GOT entry needs to be in an area in
1546 // .got.plt, not .got. Call got_section to make sure
1547 // the section has been created.
1548 target
->got_section(symtab
, layout
);
1549 Output_data_got
<32, false>* got
= target
->got_tlsdesc_section();
1550 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1551 if (!object
->local_has_got_offset(r_sym
, GOT_TYPE_TLS_DESC
))
1553 unsigned int got_offset
= got
->add_constant(0);
1554 // The local symbol value is stored in the second
1556 got
->add_local(object
, r_sym
, GOT_TYPE_TLS_DESC
);
1557 // That set the GOT offset of the local symbol to
1558 // point to the second entry, but we want it to
1559 // point to the first.
1560 object
->set_local_got_offset(r_sym
, GOT_TYPE_TLS_DESC
,
1562 Reloc_section
* rt
= target
->rel_tls_desc_section(layout
);
1563 rt
->add_absolute(elfcpp::R_386_TLS_DESC
, got
, got_offset
);
1566 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1567 unsupported_reloc_local(object
, r_type
);
1570 case elfcpp::R_386_TLS_DESC_CALL
:
1573 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1574 if (optimized_type
== tls::TLSOPT_NONE
)
1576 // Create a GOT entry for the module index.
1577 target
->got_mod_index_entry(symtab
, layout
, object
);
1579 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1580 unsupported_reloc_local(object
, r_type
);
1583 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1586 case elfcpp::R_386_TLS_IE
: // Initial-exec
1587 case elfcpp::R_386_TLS_IE_32
:
1588 case elfcpp::R_386_TLS_GOTIE
:
1589 layout
->set_has_static_tls();
1590 if (optimized_type
== tls::TLSOPT_NONE
)
1592 // For the R_386_TLS_IE relocation, we need to create a
1593 // dynamic relocation when building a shared library.
1594 if (r_type
== elfcpp::R_386_TLS_IE
1595 && parameters
->options().shared())
1597 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1599 = elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1600 rel_dyn
->add_local_relative(object
, r_sym
,
1601 elfcpp::R_386_RELATIVE
,
1602 output_section
, data_shndx
,
1603 reloc
.get_r_offset());
1605 // Create a GOT entry for the tp-relative offset.
1606 Output_data_got
<32, false>* got
1607 = target
->got_section(symtab
, layout
);
1608 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1609 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_IE_32
1610 ? elfcpp::R_386_TLS_TPOFF32
1611 : elfcpp::R_386_TLS_TPOFF
);
1612 unsigned int got_type
= (r_type
== elfcpp::R_386_TLS_IE_32
1613 ? GOT_TYPE_TLS_OFFSET
1614 : GOT_TYPE_TLS_NOFFSET
);
1615 got
->add_local_with_rel(object
, r_sym
, got_type
,
1616 target
->rel_dyn_section(layout
),
1619 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1620 unsupported_reloc_local(object
, r_type
);
1623 case elfcpp::R_386_TLS_LE
: // Local-exec
1624 case elfcpp::R_386_TLS_LE_32
:
1625 layout
->set_has_static_tls();
1626 if (output_is_shared
)
1628 // We need to create a dynamic relocation.
1629 gold_assert(lsym
.get_st_type() != elfcpp::STT_SECTION
);
1630 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(reloc
.get_r_info());
1631 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_LE_32
1632 ? elfcpp::R_386_TLS_TPOFF32
1633 : elfcpp::R_386_TLS_TPOFF
);
1634 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1635 rel_dyn
->add_local(object
, r_sym
, dyn_r_type
, output_section
,
1636 data_shndx
, reloc
.get_r_offset());
1646 case elfcpp::R_386_32PLT
:
1647 case elfcpp::R_386_TLS_GD_32
:
1648 case elfcpp::R_386_TLS_GD_PUSH
:
1649 case elfcpp::R_386_TLS_GD_CALL
:
1650 case elfcpp::R_386_TLS_GD_POP
:
1651 case elfcpp::R_386_TLS_LDM_32
:
1652 case elfcpp::R_386_TLS_LDM_PUSH
:
1653 case elfcpp::R_386_TLS_LDM_CALL
:
1654 case elfcpp::R_386_TLS_LDM_POP
:
1655 case elfcpp::R_386_USED_BY_INTEL_200
:
1657 unsupported_reloc_local(object
, r_type
);
1662 // Report an unsupported relocation against a global symbol.
1665 Target_i386::Scan::unsupported_reloc_global(
1666 Sized_relobj_file
<32, false>* object
,
1667 unsigned int r_type
,
1670 gold_error(_("%s: unsupported reloc %u against global symbol %s"),
1671 object
->name().c_str(), r_type
, gsym
->demangled_name().c_str());
1675 Target_i386::Scan::possible_function_pointer_reloc(unsigned int r_type
)
1679 case elfcpp::R_386_32
:
1680 case elfcpp::R_386_16
:
1681 case elfcpp::R_386_8
:
1682 case elfcpp::R_386_GOTOFF
:
1683 case elfcpp::R_386_GOT32
:
1694 Target_i386::Scan::local_reloc_may_be_function_pointer(
1698 Sized_relobj_file
<32, false>* ,
1701 const elfcpp::Rel
<32, false>& ,
1702 unsigned int r_type
,
1703 const elfcpp::Sym
<32, false>&)
1705 return possible_function_pointer_reloc(r_type
);
1709 Target_i386::Scan::global_reloc_may_be_function_pointer(
1713 Sized_relobj_file
<32, false>* ,
1716 const elfcpp::Rel
<32, false>& ,
1717 unsigned int r_type
,
1720 return possible_function_pointer_reloc(r_type
);
1723 // Scan a relocation for a global symbol.
1726 Target_i386::Scan::global(Symbol_table
* symtab
,
1728 Target_i386
* target
,
1729 Sized_relobj_file
<32, false>* object
,
1730 unsigned int data_shndx
,
1731 Output_section
* output_section
,
1732 const elfcpp::Rel
<32, false>& reloc
,
1733 unsigned int r_type
,
1736 // A STT_GNU_IFUNC symbol may require a PLT entry.
1737 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
1738 && this->reloc_needs_plt_for_ifunc(object
, r_type
))
1739 target
->make_plt_entry(symtab
, layout
, gsym
);
1743 case elfcpp::R_386_NONE
:
1744 case elfcpp::R_386_GNU_VTINHERIT
:
1745 case elfcpp::R_386_GNU_VTENTRY
:
1748 case elfcpp::R_386_32
:
1749 case elfcpp::R_386_16
:
1750 case elfcpp::R_386_8
:
1752 // Make a PLT entry if necessary.
1753 if (gsym
->needs_plt_entry())
1755 target
->make_plt_entry(symtab
, layout
, gsym
);
1756 // Since this is not a PC-relative relocation, we may be
1757 // taking the address of a function. In that case we need to
1758 // set the entry in the dynamic symbol table to the address of
1760 if (gsym
->is_from_dynobj() && !parameters
->options().shared())
1761 gsym
->set_needs_dynsym_value();
1763 // Make a dynamic relocation if necessary.
1764 if (gsym
->needs_dynamic_reloc(Scan::get_reference_flags(r_type
)))
1766 if (gsym
->may_need_copy_reloc())
1768 target
->copy_reloc(symtab
, layout
, object
,
1769 data_shndx
, output_section
, gsym
, reloc
);
1771 else if (r_type
== elfcpp::R_386_32
1772 && gsym
->type() == elfcpp::STT_GNU_IFUNC
1773 && gsym
->can_use_relative_reloc(false)
1774 && !gsym
->is_from_dynobj()
1775 && !gsym
->is_undefined()
1776 && !gsym
->is_preemptible())
1778 // Use an IRELATIVE reloc for a locally defined
1779 // STT_GNU_IFUNC symbol. This makes a function
1780 // address in a PIE executable match the address in a
1781 // shared library that it links against.
1782 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1783 rel_dyn
->add_symbolless_global_addend(gsym
,
1784 elfcpp::R_386_IRELATIVE
,
1787 reloc
.get_r_offset());
1789 else if (r_type
== elfcpp::R_386_32
1790 && gsym
->can_use_relative_reloc(false))
1792 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1793 rel_dyn
->add_global_relative(gsym
, elfcpp::R_386_RELATIVE
,
1794 output_section
, object
,
1795 data_shndx
, reloc
.get_r_offset());
1799 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1800 rel_dyn
->add_global(gsym
, r_type
, output_section
, object
,
1801 data_shndx
, reloc
.get_r_offset());
1807 case elfcpp::R_386_PC32
:
1808 case elfcpp::R_386_PC16
:
1809 case elfcpp::R_386_PC8
:
1811 // Make a PLT entry if necessary.
1812 if (gsym
->needs_plt_entry())
1814 // These relocations are used for function calls only in
1815 // non-PIC code. For a 32-bit relocation in a shared library,
1816 // we'll need a text relocation anyway, so we can skip the
1817 // PLT entry and let the dynamic linker bind the call directly
1818 // to the target. For smaller relocations, we should use a
1819 // PLT entry to ensure that the call can reach.
1820 if (!parameters
->options().shared()
1821 || r_type
!= elfcpp::R_386_PC32
)
1822 target
->make_plt_entry(symtab
, layout
, gsym
);
1824 // Make a dynamic relocation if necessary.
1825 if (gsym
->needs_dynamic_reloc(Scan::get_reference_flags(r_type
)))
1827 if (gsym
->may_need_copy_reloc())
1829 target
->copy_reloc(symtab
, layout
, object
,
1830 data_shndx
, output_section
, gsym
, reloc
);
1834 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1835 rel_dyn
->add_global(gsym
, r_type
, output_section
, object
,
1836 data_shndx
, reloc
.get_r_offset());
1842 case elfcpp::R_386_GOT32
:
1844 // The symbol requires a GOT entry.
1845 Output_data_got
<32, false>* got
= target
->got_section(symtab
, layout
);
1846 if (gsym
->final_value_is_known())
1848 // For a STT_GNU_IFUNC symbol we want the PLT address.
1849 if (gsym
->type() == elfcpp::STT_GNU_IFUNC
)
1850 got
->add_global_plt(gsym
, GOT_TYPE_STANDARD
);
1852 got
->add_global(gsym
, GOT_TYPE_STANDARD
);
1856 // If this symbol is not fully resolved, we need to add a
1857 // GOT entry with a dynamic relocation.
1858 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
1859 if (gsym
->is_from_dynobj()
1860 || gsym
->is_undefined()
1861 || gsym
->is_preemptible()
1862 || (gsym
->type() == elfcpp::STT_GNU_IFUNC
1863 && parameters
->options().output_is_position_independent()))
1864 got
->add_global_with_rel(gsym
, GOT_TYPE_STANDARD
,
1865 rel_dyn
, elfcpp::R_386_GLOB_DAT
);
1868 // For a STT_GNU_IFUNC symbol we want to write the PLT
1869 // offset into the GOT, so that function pointer
1870 // comparisons work correctly.
1872 if (gsym
->type() != elfcpp::STT_GNU_IFUNC
)
1873 is_new
= got
->add_global(gsym
, GOT_TYPE_STANDARD
);
1876 is_new
= got
->add_global_plt(gsym
, GOT_TYPE_STANDARD
);
1877 // Tell the dynamic linker to use the PLT address
1878 // when resolving relocations.
1879 if (gsym
->is_from_dynobj()
1880 && !parameters
->options().shared())
1881 gsym
->set_needs_dynsym_value();
1885 unsigned int got_off
= gsym
->got_offset(GOT_TYPE_STANDARD
);
1886 rel_dyn
->add_global_relative(gsym
, elfcpp::R_386_RELATIVE
,
1894 case elfcpp::R_386_PLT32
:
1895 // If the symbol is fully resolved, this is just a PC32 reloc.
1896 // Otherwise we need a PLT entry.
1897 if (gsym
->final_value_is_known())
1899 // If building a shared library, we can also skip the PLT entry
1900 // if the symbol is defined in the output file and is protected
1902 if (gsym
->is_defined()
1903 && !gsym
->is_from_dynobj()
1904 && !gsym
->is_preemptible())
1906 target
->make_plt_entry(symtab
, layout
, gsym
);
1909 case elfcpp::R_386_GOTOFF
:
1910 case elfcpp::R_386_GOTPC
:
1911 // We need a GOT section.
1912 target
->got_section(symtab
, layout
);
1915 // These are relocations which should only be seen by the
1916 // dynamic linker, and should never be seen here.
1917 case elfcpp::R_386_COPY
:
1918 case elfcpp::R_386_GLOB_DAT
:
1919 case elfcpp::R_386_JUMP_SLOT
:
1920 case elfcpp::R_386_RELATIVE
:
1921 case elfcpp::R_386_IRELATIVE
:
1922 case elfcpp::R_386_TLS_TPOFF
:
1923 case elfcpp::R_386_TLS_DTPMOD32
:
1924 case elfcpp::R_386_TLS_DTPOFF32
:
1925 case elfcpp::R_386_TLS_TPOFF32
:
1926 case elfcpp::R_386_TLS_DESC
:
1927 gold_error(_("%s: unexpected reloc %u in object file"),
1928 object
->name().c_str(), r_type
);
1931 // These are initial tls relocs, which are expected when
1933 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1934 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
1935 case elfcpp::R_386_TLS_DESC_CALL
:
1936 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
1937 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
1938 case elfcpp::R_386_TLS_IE
: // Initial-exec
1939 case elfcpp::R_386_TLS_IE_32
:
1940 case elfcpp::R_386_TLS_GOTIE
:
1941 case elfcpp::R_386_TLS_LE
: // Local-exec
1942 case elfcpp::R_386_TLS_LE_32
:
1944 const bool is_final
= gsym
->final_value_is_known();
1945 const tls::Tls_optimization optimized_type
1946 = Target_i386::optimize_tls_reloc(is_final
, r_type
);
1949 case elfcpp::R_386_TLS_GD
: // Global-dynamic
1950 if (optimized_type
== tls::TLSOPT_NONE
)
1952 // Create a pair of GOT entries for the module index and
1953 // dtv-relative offset.
1954 Output_data_got
<32, false>* got
1955 = target
->got_section(symtab
, layout
);
1956 got
->add_global_pair_with_rel(gsym
, GOT_TYPE_TLS_PAIR
,
1957 target
->rel_dyn_section(layout
),
1958 elfcpp::R_386_TLS_DTPMOD32
,
1959 elfcpp::R_386_TLS_DTPOFF32
);
1961 else if (optimized_type
== tls::TLSOPT_TO_IE
)
1963 // Create a GOT entry for the tp-relative offset.
1964 Output_data_got
<32, false>* got
1965 = target
->got_section(symtab
, layout
);
1966 got
->add_global_with_rel(gsym
, GOT_TYPE_TLS_NOFFSET
,
1967 target
->rel_dyn_section(layout
),
1968 elfcpp::R_386_TLS_TPOFF
);
1970 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1971 unsupported_reloc_global(object
, r_type
, gsym
);
1974 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (~oliva url)
1975 target
->define_tls_base_symbol(symtab
, layout
);
1976 if (optimized_type
== tls::TLSOPT_NONE
)
1978 // Create a double GOT entry with an R_386_TLS_DESC
1979 // reloc. The R_386_TLS_DESC reloc is resolved
1980 // lazily, so the GOT entry needs to be in an area in
1981 // .got.plt, not .got. Call got_section to make sure
1982 // the section has been created.
1983 target
->got_section(symtab
, layout
);
1984 Output_data_got
<32, false>* got
= target
->got_tlsdesc_section();
1985 Reloc_section
* rt
= target
->rel_tls_desc_section(layout
);
1986 got
->add_global_pair_with_rel(gsym
, GOT_TYPE_TLS_DESC
, rt
,
1987 elfcpp::R_386_TLS_DESC
, 0);
1989 else if (optimized_type
== tls::TLSOPT_TO_IE
)
1991 // Create a GOT entry for the tp-relative offset.
1992 Output_data_got
<32, false>* got
1993 = target
->got_section(symtab
, layout
);
1994 got
->add_global_with_rel(gsym
, GOT_TYPE_TLS_NOFFSET
,
1995 target
->rel_dyn_section(layout
),
1996 elfcpp::R_386_TLS_TPOFF
);
1998 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
1999 unsupported_reloc_global(object
, r_type
, gsym
);
2002 case elfcpp::R_386_TLS_DESC_CALL
:
2005 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
2006 if (optimized_type
== tls::TLSOPT_NONE
)
2008 // Create a GOT entry for the module index.
2009 target
->got_mod_index_entry(symtab
, layout
, object
);
2011 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2012 unsupported_reloc_global(object
, r_type
, gsym
);
2015 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
2018 case elfcpp::R_386_TLS_IE
: // Initial-exec
2019 case elfcpp::R_386_TLS_IE_32
:
2020 case elfcpp::R_386_TLS_GOTIE
:
2021 layout
->set_has_static_tls();
2022 if (optimized_type
== tls::TLSOPT_NONE
)
2024 // For the R_386_TLS_IE relocation, we need to create a
2025 // dynamic relocation when building a shared library.
2026 if (r_type
== elfcpp::R_386_TLS_IE
2027 && parameters
->options().shared())
2029 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
2030 rel_dyn
->add_global_relative(gsym
, elfcpp::R_386_RELATIVE
,
2031 output_section
, object
,
2033 reloc
.get_r_offset());
2035 // Create a GOT entry for the tp-relative offset.
2036 Output_data_got
<32, false>* got
2037 = target
->got_section(symtab
, layout
);
2038 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_IE_32
2039 ? elfcpp::R_386_TLS_TPOFF32
2040 : elfcpp::R_386_TLS_TPOFF
);
2041 unsigned int got_type
= (r_type
== elfcpp::R_386_TLS_IE_32
2042 ? GOT_TYPE_TLS_OFFSET
2043 : GOT_TYPE_TLS_NOFFSET
);
2044 got
->add_global_with_rel(gsym
, got_type
,
2045 target
->rel_dyn_section(layout
),
2048 else if (optimized_type
!= tls::TLSOPT_TO_LE
)
2049 unsupported_reloc_global(object
, r_type
, gsym
);
2052 case elfcpp::R_386_TLS_LE
: // Local-exec
2053 case elfcpp::R_386_TLS_LE_32
:
2054 layout
->set_has_static_tls();
2055 if (parameters
->options().shared())
2057 // We need to create a dynamic relocation.
2058 unsigned int dyn_r_type
= (r_type
== elfcpp::R_386_TLS_LE_32
2059 ? elfcpp::R_386_TLS_TPOFF32
2060 : elfcpp::R_386_TLS_TPOFF
);
2061 Reloc_section
* rel_dyn
= target
->rel_dyn_section(layout
);
2062 rel_dyn
->add_global(gsym
, dyn_r_type
, output_section
, object
,
2063 data_shndx
, reloc
.get_r_offset());
2073 case elfcpp::R_386_32PLT
:
2074 case elfcpp::R_386_TLS_GD_32
:
2075 case elfcpp::R_386_TLS_GD_PUSH
:
2076 case elfcpp::R_386_TLS_GD_CALL
:
2077 case elfcpp::R_386_TLS_GD_POP
:
2078 case elfcpp::R_386_TLS_LDM_32
:
2079 case elfcpp::R_386_TLS_LDM_PUSH
:
2080 case elfcpp::R_386_TLS_LDM_CALL
:
2081 case elfcpp::R_386_TLS_LDM_POP
:
2082 case elfcpp::R_386_USED_BY_INTEL_200
:
2084 unsupported_reloc_global(object
, r_type
, gsym
);
2089 // Process relocations for gc.
2092 Target_i386::gc_process_relocs(Symbol_table
* symtab
,
2094 Sized_relobj_file
<32, false>* object
,
2095 unsigned int data_shndx
,
2097 const unsigned char* prelocs
,
2099 Output_section
* output_section
,
2100 bool needs_special_offset_handling
,
2101 size_t local_symbol_count
,
2102 const unsigned char* plocal_symbols
)
2104 gold::gc_process_relocs
<32, false, Target_i386
, elfcpp::SHT_REL
,
2106 Target_i386::Relocatable_size_for_reloc
>(
2115 needs_special_offset_handling
,
2120 // Scan relocations for a section.
2123 Target_i386::scan_relocs(Symbol_table
* symtab
,
2125 Sized_relobj_file
<32, false>* object
,
2126 unsigned int data_shndx
,
2127 unsigned int sh_type
,
2128 const unsigned char* prelocs
,
2130 Output_section
* output_section
,
2131 bool needs_special_offset_handling
,
2132 size_t local_symbol_count
,
2133 const unsigned char* plocal_symbols
)
2135 if (sh_type
== elfcpp::SHT_RELA
)
2137 gold_error(_("%s: unsupported RELA reloc section"),
2138 object
->name().c_str());
2142 gold::scan_relocs
<32, false, Target_i386
, elfcpp::SHT_REL
,
2152 needs_special_offset_handling
,
2157 // Finalize the sections.
2160 Target_i386::do_finalize_sections(
2162 const Input_objects
*,
2163 Symbol_table
* symtab
)
2165 const Reloc_section
* rel_plt
= (this->plt_
== NULL
2167 : this->plt_
->rel_plt());
2168 layout
->add_target_dynamic_tags(true, this->got_plt_
, rel_plt
,
2169 this->rel_dyn_
, true, false);
2171 // Emit any relocs we saved in an attempt to avoid generating COPY
2173 if (this->copy_relocs_
.any_saved_relocs())
2174 this->copy_relocs_
.emit(this->rel_dyn_section(layout
));
2176 // Set the size of the _GLOBAL_OFFSET_TABLE_ symbol to the size of
2177 // the .got.plt section.
2178 Symbol
* sym
= this->global_offset_table_
;
2181 uint32_t data_size
= this->got_plt_
->current_data_size();
2182 symtab
->get_sized_symbol
<32>(sym
)->set_symsize(data_size
);
2185 if (parameters
->doing_static_link() && this->plt_
== NULL
)
2187 // If linking statically, make sure that the __rel_iplt symbols
2188 // were defined if necessary, even if we didn't create a PLT.
2189 static const Define_symbol_in_segment syms
[] =
2192 "__rel_iplt_start", // name
2193 elfcpp::PT_LOAD
, // segment_type
2194 elfcpp::PF_W
, // segment_flags_set
2195 elfcpp::PF(0), // segment_flags_clear
2198 elfcpp::STT_NOTYPE
, // type
2199 elfcpp::STB_GLOBAL
, // binding
2200 elfcpp::STV_HIDDEN
, // visibility
2202 Symbol::SEGMENT_START
, // offset_from_base
2206 "__rel_iplt_end", // name
2207 elfcpp::PT_LOAD
, // segment_type
2208 elfcpp::PF_W
, // segment_flags_set
2209 elfcpp::PF(0), // segment_flags_clear
2212 elfcpp::STT_NOTYPE
, // type
2213 elfcpp::STB_GLOBAL
, // binding
2214 elfcpp::STV_HIDDEN
, // visibility
2216 Symbol::SEGMENT_START
, // offset_from_base
2221 symtab
->define_symbols(layout
, 2, syms
,
2222 layout
->script_options()->saw_sections_clause());
2226 // Return whether a direct absolute static relocation needs to be applied.
2227 // In cases where Scan::local() or Scan::global() has created
2228 // a dynamic relocation other than R_386_RELATIVE, the addend
2229 // of the relocation is carried in the data, and we must not
2230 // apply the static relocation.
2233 Target_i386::Relocate::should_apply_static_reloc(const Sized_symbol
<32>* gsym
,
2234 unsigned int r_type
,
2236 Output_section
* output_section
)
2238 // If the output section is not allocated, then we didn't call
2239 // scan_relocs, we didn't create a dynamic reloc, and we must apply
2241 if ((output_section
->flags() & elfcpp::SHF_ALLOC
) == 0)
2244 int ref_flags
= Scan::get_reference_flags(r_type
);
2246 // For local symbols, we will have created a non-RELATIVE dynamic
2247 // relocation only if (a) the output is position independent,
2248 // (b) the relocation is absolute (not pc- or segment-relative), and
2249 // (c) the relocation is not 32 bits wide.
2251 return !(parameters
->options().output_is_position_independent()
2252 && (ref_flags
& Symbol::ABSOLUTE_REF
)
2255 // For global symbols, we use the same helper routines used in the
2256 // scan pass. If we did not create a dynamic relocation, or if we
2257 // created a RELATIVE dynamic relocation, we should apply the static
2259 bool has_dyn
= gsym
->needs_dynamic_reloc(ref_flags
);
2260 bool is_rel
= (ref_flags
& Symbol::ABSOLUTE_REF
)
2261 && gsym
->can_use_relative_reloc(ref_flags
2262 & Symbol::FUNCTION_CALL
);
2263 return !has_dyn
|| is_rel
;
2266 // Perform a relocation.
2269 Target_i386::Relocate::relocate(const Relocate_info
<32, false>* relinfo
,
2270 Target_i386
* target
,
2271 Output_section
* output_section
,
2273 const elfcpp::Rel
<32, false>& rel
,
2274 unsigned int r_type
,
2275 const Sized_symbol
<32>* gsym
,
2276 const Symbol_value
<32>* psymval
,
2277 unsigned char* view
,
2278 elfcpp::Elf_types
<32>::Elf_Addr address
,
2279 section_size_type view_size
)
2281 if (this->skip_call_tls_get_addr_
)
2283 if ((r_type
!= elfcpp::R_386_PLT32
2284 && r_type
!= elfcpp::R_386_PC32
)
2286 || strcmp(gsym
->name(), "___tls_get_addr") != 0)
2287 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2288 _("missing expected TLS relocation"));
2291 this->skip_call_tls_get_addr_
= false;
2296 const Sized_relobj_file
<32, false>* object
= relinfo
->object
;
2298 // Pick the value to use for symbols defined in shared objects.
2299 Symbol_value
<32> symval
;
2301 && gsym
->type() == elfcpp::STT_GNU_IFUNC
2302 && r_type
== elfcpp::R_386_32
2303 && gsym
->needs_dynamic_reloc(Scan::get_reference_flags(r_type
))
2304 && gsym
->can_use_relative_reloc(false)
2305 && !gsym
->is_from_dynobj()
2306 && !gsym
->is_undefined()
2307 && !gsym
->is_preemptible())
2309 // In this case we are generating a R_386_IRELATIVE reloc. We
2310 // want to use the real value of the symbol, not the PLT offset.
2312 else if (gsym
!= NULL
2313 && gsym
->use_plt_offset(Scan::get_reference_flags(r_type
)))
2315 symval
.set_output_value(target
->plt_section()->address()
2316 + gsym
->plt_offset());
2319 else if (gsym
== NULL
&& psymval
->is_ifunc_symbol())
2321 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
2322 if (object
->local_has_plt_offset(r_sym
))
2324 symval
.set_output_value(target
->plt_section()->address()
2325 + object
->local_plt_offset(r_sym
));
2330 // Get the GOT offset if needed.
2331 // The GOT pointer points to the end of the GOT section.
2332 // We need to subtract the size of the GOT section to get
2333 // the actual offset to use in the relocation.
2334 bool have_got_offset
= false;
2335 unsigned int got_offset
= 0;
2338 case elfcpp::R_386_GOT32
:
2341 gold_assert(gsym
->has_got_offset(GOT_TYPE_STANDARD
));
2342 got_offset
= (gsym
->got_offset(GOT_TYPE_STANDARD
)
2343 - target
->got_size());
2347 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
2348 gold_assert(object
->local_has_got_offset(r_sym
, GOT_TYPE_STANDARD
));
2349 got_offset
= (object
->local_got_offset(r_sym
, GOT_TYPE_STANDARD
)
2350 - target
->got_size());
2352 have_got_offset
= true;
2361 case elfcpp::R_386_NONE
:
2362 case elfcpp::R_386_GNU_VTINHERIT
:
2363 case elfcpp::R_386_GNU_VTENTRY
:
2366 case elfcpp::R_386_32
:
2367 if (should_apply_static_reloc(gsym
, r_type
, true, output_section
))
2368 Relocate_functions
<32, false>::rel32(view
, object
, psymval
);
2371 case elfcpp::R_386_PC32
:
2372 if (should_apply_static_reloc(gsym
, r_type
, true, output_section
))
2373 Relocate_functions
<32, false>::pcrel32(view
, object
, psymval
, address
);
2376 case elfcpp::R_386_16
:
2377 if (should_apply_static_reloc(gsym
, r_type
, false, output_section
))
2378 Relocate_functions
<32, false>::rel16(view
, object
, psymval
);
2381 case elfcpp::R_386_PC16
:
2382 if (should_apply_static_reloc(gsym
, r_type
, false, output_section
))
2383 Relocate_functions
<32, false>::pcrel16(view
, object
, psymval
, address
);
2386 case elfcpp::R_386_8
:
2387 if (should_apply_static_reloc(gsym
, r_type
, false, output_section
))
2388 Relocate_functions
<32, false>::rel8(view
, object
, psymval
);
2391 case elfcpp::R_386_PC8
:
2392 if (should_apply_static_reloc(gsym
, r_type
, false, output_section
))
2393 Relocate_functions
<32, false>::pcrel8(view
, object
, psymval
, address
);
2396 case elfcpp::R_386_PLT32
:
2397 gold_assert(gsym
== NULL
2398 || gsym
->has_plt_offset()
2399 || gsym
->final_value_is_known()
2400 || (gsym
->is_defined()
2401 && !gsym
->is_from_dynobj()
2402 && !gsym
->is_preemptible()));
2403 Relocate_functions
<32, false>::pcrel32(view
, object
, psymval
, address
);
2406 case elfcpp::R_386_GOT32
:
2407 gold_assert(have_got_offset
);
2408 Relocate_functions
<32, false>::rel32(view
, got_offset
);
2411 case elfcpp::R_386_GOTOFF
:
2413 elfcpp::Elf_types
<32>::Elf_Addr value
;
2414 value
= (psymval
->value(object
, 0)
2415 - target
->got_plt_section()->address());
2416 Relocate_functions
<32, false>::rel32(view
, value
);
2420 case elfcpp::R_386_GOTPC
:
2422 elfcpp::Elf_types
<32>::Elf_Addr value
;
2423 value
= target
->got_plt_section()->address();
2424 Relocate_functions
<32, false>::pcrel32(view
, value
, address
);
2428 case elfcpp::R_386_COPY
:
2429 case elfcpp::R_386_GLOB_DAT
:
2430 case elfcpp::R_386_JUMP_SLOT
:
2431 case elfcpp::R_386_RELATIVE
:
2432 case elfcpp::R_386_IRELATIVE
:
2433 // These are outstanding tls relocs, which are unexpected when
2435 case elfcpp::R_386_TLS_TPOFF
:
2436 case elfcpp::R_386_TLS_DTPMOD32
:
2437 case elfcpp::R_386_TLS_DTPOFF32
:
2438 case elfcpp::R_386_TLS_TPOFF32
:
2439 case elfcpp::R_386_TLS_DESC
:
2440 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2441 _("unexpected reloc %u in object file"),
2445 // These are initial tls relocs, which are expected when
2447 case elfcpp::R_386_TLS_GD
: // Global-dynamic
2448 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
2449 case elfcpp::R_386_TLS_DESC_CALL
:
2450 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
2451 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
2452 case elfcpp::R_386_TLS_IE
: // Initial-exec
2453 case elfcpp::R_386_TLS_IE_32
:
2454 case elfcpp::R_386_TLS_GOTIE
:
2455 case elfcpp::R_386_TLS_LE
: // Local-exec
2456 case elfcpp::R_386_TLS_LE_32
:
2457 this->relocate_tls(relinfo
, target
, relnum
, rel
, r_type
, gsym
, psymval
,
2458 view
, address
, view_size
);
2461 case elfcpp::R_386_32PLT
:
2462 case elfcpp::R_386_TLS_GD_32
:
2463 case elfcpp::R_386_TLS_GD_PUSH
:
2464 case elfcpp::R_386_TLS_GD_CALL
:
2465 case elfcpp::R_386_TLS_GD_POP
:
2466 case elfcpp::R_386_TLS_LDM_32
:
2467 case elfcpp::R_386_TLS_LDM_PUSH
:
2468 case elfcpp::R_386_TLS_LDM_CALL
:
2469 case elfcpp::R_386_TLS_LDM_POP
:
2470 case elfcpp::R_386_USED_BY_INTEL_200
:
2472 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2473 _("unsupported reloc %u"),
2481 // Perform a TLS relocation.
2484 Target_i386::Relocate::relocate_tls(const Relocate_info
<32, false>* relinfo
,
2485 Target_i386
* target
,
2487 const elfcpp::Rel
<32, false>& rel
,
2488 unsigned int r_type
,
2489 const Sized_symbol
<32>* gsym
,
2490 const Symbol_value
<32>* psymval
,
2491 unsigned char* view
,
2492 elfcpp::Elf_types
<32>::Elf_Addr
,
2493 section_size_type view_size
)
2495 Output_segment
* tls_segment
= relinfo
->layout
->tls_segment();
2497 const Sized_relobj_file
<32, false>* object
= relinfo
->object
;
2499 elfcpp::Elf_types
<32>::Elf_Addr value
= psymval
->value(object
, 0);
2501 const bool is_final
= (gsym
== NULL
2502 ? !parameters
->options().shared()
2503 : gsym
->final_value_is_known());
2504 const tls::Tls_optimization optimized_type
2505 = Target_i386::optimize_tls_reloc(is_final
, r_type
);
2508 case elfcpp::R_386_TLS_GD
: // Global-dynamic
2509 if (optimized_type
== tls::TLSOPT_TO_LE
)
2511 gold_assert(tls_segment
!= NULL
);
2512 this->tls_gd_to_le(relinfo
, relnum
, tls_segment
,
2513 rel
, r_type
, value
, view
,
2519 unsigned int got_type
= (optimized_type
== tls::TLSOPT_TO_IE
2520 ? GOT_TYPE_TLS_NOFFSET
2521 : GOT_TYPE_TLS_PAIR
);
2522 unsigned int got_offset
;
2525 gold_assert(gsym
->has_got_offset(got_type
));
2526 got_offset
= gsym
->got_offset(got_type
) - target
->got_size();
2530 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
2531 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
2532 got_offset
= (object
->local_got_offset(r_sym
, got_type
)
2533 - target
->got_size());
2535 if (optimized_type
== tls::TLSOPT_TO_IE
)
2537 gold_assert(tls_segment
!= NULL
);
2538 this->tls_gd_to_ie(relinfo
, relnum
, tls_segment
, rel
, r_type
,
2539 got_offset
, view
, view_size
);
2542 else if (optimized_type
== tls::TLSOPT_NONE
)
2544 // Relocate the field with the offset of the pair of GOT
2546 Relocate_functions
<32, false>::rel32(view
, got_offset
);
2550 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2551 _("unsupported reloc %u"),
2555 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
2556 case elfcpp::R_386_TLS_DESC_CALL
:
2557 this->local_dynamic_type_
= LOCAL_DYNAMIC_GNU
;
2558 if (optimized_type
== tls::TLSOPT_TO_LE
)
2560 gold_assert(tls_segment
!= NULL
);
2561 this->tls_desc_gd_to_le(relinfo
, relnum
, tls_segment
,
2562 rel
, r_type
, value
, view
,
2568 unsigned int got_type
= (optimized_type
== tls::TLSOPT_TO_IE
2569 ? GOT_TYPE_TLS_NOFFSET
2570 : GOT_TYPE_TLS_DESC
);
2571 unsigned int got_offset
= 0;
2572 if (r_type
== elfcpp::R_386_TLS_GOTDESC
2573 && optimized_type
== tls::TLSOPT_NONE
)
2575 // We created GOT entries in the .got.tlsdesc portion of
2576 // the .got.plt section, but the offset stored in the
2577 // symbol is the offset within .got.tlsdesc.
2578 got_offset
= (target
->got_size()
2579 + target
->got_plt_section()->data_size());
2583 gold_assert(gsym
->has_got_offset(got_type
));
2584 got_offset
+= gsym
->got_offset(got_type
) - target
->got_size();
2588 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
2589 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
2590 got_offset
+= (object
->local_got_offset(r_sym
, got_type
)
2591 - target
->got_size());
2593 if (optimized_type
== tls::TLSOPT_TO_IE
)
2595 gold_assert(tls_segment
!= NULL
);
2596 this->tls_desc_gd_to_ie(relinfo
, relnum
, tls_segment
, rel
, r_type
,
2597 got_offset
, view
, view_size
);
2600 else if (optimized_type
== tls::TLSOPT_NONE
)
2602 if (r_type
== elfcpp::R_386_TLS_GOTDESC
)
2604 // Relocate the field with the offset of the pair of GOT
2606 Relocate_functions
<32, false>::rel32(view
, got_offset
);
2611 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2612 _("unsupported reloc %u"),
2616 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
2617 if (this->local_dynamic_type_
== LOCAL_DYNAMIC_SUN
)
2619 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2620 _("both SUN and GNU model "
2621 "TLS relocations"));
2624 this->local_dynamic_type_
= LOCAL_DYNAMIC_GNU
;
2625 if (optimized_type
== tls::TLSOPT_TO_LE
)
2627 gold_assert(tls_segment
!= NULL
);
2628 this->tls_ld_to_le(relinfo
, relnum
, tls_segment
, rel
, r_type
,
2629 value
, view
, view_size
);
2632 else if (optimized_type
== tls::TLSOPT_NONE
)
2634 // Relocate the field with the offset of the GOT entry for
2635 // the module index.
2636 unsigned int got_offset
;
2637 got_offset
= (target
->got_mod_index_entry(NULL
, NULL
, NULL
)
2638 - target
->got_size());
2639 Relocate_functions
<32, false>::rel32(view
, got_offset
);
2642 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2643 _("unsupported reloc %u"),
2647 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
2648 if (optimized_type
== tls::TLSOPT_TO_LE
)
2650 // This reloc can appear in debugging sections, in which
2651 // case we must not convert to local-exec. We decide what
2652 // to do based on whether the section is marked as
2653 // containing executable code. That is what the GNU linker
2655 elfcpp::Shdr
<32, false> shdr(relinfo
->data_shdr
);
2656 if ((shdr
.get_sh_flags() & elfcpp::SHF_EXECINSTR
) != 0)
2658 gold_assert(tls_segment
!= NULL
);
2659 value
-= tls_segment
->memsz();
2662 Relocate_functions
<32, false>::rel32(view
, value
);
2665 case elfcpp::R_386_TLS_IE
: // Initial-exec
2666 case elfcpp::R_386_TLS_GOTIE
:
2667 case elfcpp::R_386_TLS_IE_32
:
2668 if (optimized_type
== tls::TLSOPT_TO_LE
)
2670 gold_assert(tls_segment
!= NULL
);
2671 Target_i386::Relocate::tls_ie_to_le(relinfo
, relnum
, tls_segment
,
2672 rel
, r_type
, value
, view
,
2676 else if (optimized_type
== tls::TLSOPT_NONE
)
2678 // Relocate the field with the offset of the GOT entry for
2679 // the tp-relative offset of the symbol.
2680 unsigned int got_type
= (r_type
== elfcpp::R_386_TLS_IE_32
2681 ? GOT_TYPE_TLS_OFFSET
2682 : GOT_TYPE_TLS_NOFFSET
);
2683 unsigned int got_offset
;
2686 gold_assert(gsym
->has_got_offset(got_type
));
2687 got_offset
= gsym
->got_offset(got_type
);
2691 unsigned int r_sym
= elfcpp::elf_r_sym
<32>(rel
.get_r_info());
2692 gold_assert(object
->local_has_got_offset(r_sym
, got_type
));
2693 got_offset
= object
->local_got_offset(r_sym
, got_type
);
2695 // For the R_386_TLS_IE relocation, we need to apply the
2696 // absolute address of the GOT entry.
2697 if (r_type
== elfcpp::R_386_TLS_IE
)
2698 got_offset
+= target
->got_plt_section()->address();
2699 // All GOT offsets are relative to the end of the GOT.
2700 got_offset
-= target
->got_size();
2701 Relocate_functions
<32, false>::rel32(view
, got_offset
);
2704 gold_error_at_location(relinfo
, relnum
, rel
.get_r_offset(),
2705 _("unsupported reloc %u"),
2709 case elfcpp::R_386_TLS_LE
: // Local-exec
2710 // If we're creating a shared library, a dynamic relocation will
2711 // have been created for this location, so do not apply it now.
2712 if (!parameters
->options().shared())
2714 gold_assert(tls_segment
!= NULL
);
2715 value
-= tls_segment
->memsz();
2716 Relocate_functions
<32, false>::rel32(view
, value
);
2720 case elfcpp::R_386_TLS_LE_32
:
2721 // If we're creating a shared library, a dynamic relocation will
2722 // have been created for this location, so do not apply it now.
2723 if (!parameters
->options().shared())
2725 gold_assert(tls_segment
!= NULL
);
2726 value
= tls_segment
->memsz() - value
;
2727 Relocate_functions
<32, false>::rel32(view
, value
);
2733 // Do a relocation in which we convert a TLS General-Dynamic to a
2737 Target_i386::Relocate::tls_gd_to_le(const Relocate_info
<32, false>* relinfo
,
2739 Output_segment
* tls_segment
,
2740 const elfcpp::Rel
<32, false>& rel
,
2742 elfcpp::Elf_types
<32>::Elf_Addr value
,
2743 unsigned char* view
,
2744 section_size_type view_size
)
2746 // leal foo(,%reg,1),%eax; call ___tls_get_addr
2747 // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
2748 // leal foo(%reg),%eax; call ___tls_get_addr
2749 // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
2751 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2752 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 9);
2754 unsigned char op1
= view
[-1];
2755 unsigned char op2
= view
[-2];
2757 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2758 op2
== 0x8d || op2
== 0x04);
2759 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[4] == 0xe8);
2765 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -3);
2766 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[-3] == 0x8d);
2767 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2768 ((op1
& 0xc7) == 0x05 && op1
!= (4 << 3)));
2769 memcpy(view
- 3, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
2773 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2774 (op1
& 0xf8) == 0x80 && (op1
& 7) != 4);
2775 if (rel
.get_r_offset() + 9 < view_size
2778 // There is a trailing nop. Use the size byte subl.
2779 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
2784 // Use the five byte subl.
2785 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
2789 value
= tls_segment
->memsz() - value
;
2790 Relocate_functions
<32, false>::rel32(view
+ roff
, value
);
2792 // The next reloc should be a PLT32 reloc against __tls_get_addr.
2794 this->skip_call_tls_get_addr_
= true;
2797 // Do a relocation in which we convert a TLS General-Dynamic to an
2801 Target_i386::Relocate::tls_gd_to_ie(const Relocate_info
<32, false>* relinfo
,
2804 const elfcpp::Rel
<32, false>& rel
,
2806 elfcpp::Elf_types
<32>::Elf_Addr value
,
2807 unsigned char* view
,
2808 section_size_type view_size
)
2810 // leal foo(,%ebx,1),%eax; call ___tls_get_addr
2811 // ==> movl %gs:0,%eax; addl foo@gotntpoff(%ebx),%eax
2813 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2814 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 9);
2816 unsigned char op1
= view
[-1];
2817 unsigned char op2
= view
[-2];
2819 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2820 op2
== 0x8d || op2
== 0x04);
2821 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[4] == 0xe8);
2825 // FIXME: For now, support only the first (SIB) form.
2826 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), op2
== 0x04);
2830 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -3);
2831 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[-3] == 0x8d);
2832 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2833 ((op1
& 0xc7) == 0x05 && op1
!= (4 << 3)));
2834 memcpy(view
- 3, "\x65\xa1\0\0\0\0\x03\x83\0\0\0", 12);
2838 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2839 (op1
& 0xf8) == 0x80 && (op1
& 7) != 4);
2840 if (rel
.get_r_offset() + 9 < view_size
2843 // FIXME: This is not the right instruction sequence.
2844 // There is a trailing nop. Use the size byte subl.
2845 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
2850 // FIXME: This is not the right instruction sequence.
2851 // Use the five byte subl.
2852 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
2856 Relocate_functions
<32, false>::rel32(view
+ roff
, value
);
2858 // The next reloc should be a PLT32 reloc against __tls_get_addr.
2860 this->skip_call_tls_get_addr_
= true;
2863 // Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL
2864 // General-Dynamic to a Local-Exec.
2867 Target_i386::Relocate::tls_desc_gd_to_le(
2868 const Relocate_info
<32, false>* relinfo
,
2870 Output_segment
* tls_segment
,
2871 const elfcpp::Rel
<32, false>& rel
,
2872 unsigned int r_type
,
2873 elfcpp::Elf_types
<32>::Elf_Addr value
,
2874 unsigned char* view
,
2875 section_size_type view_size
)
2877 if (r_type
== elfcpp::R_386_TLS_GOTDESC
)
2879 // leal foo@TLSDESC(%ebx), %eax
2880 // ==> leal foo@NTPOFF, %eax
2881 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2882 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
2883 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2884 view
[-2] == 0x8d && view
[-1] == 0x83);
2886 value
-= tls_segment
->memsz();
2887 Relocate_functions
<32, false>::rel32(view
, value
);
2891 // call *foo@TLSCALL(%eax)
2893 gold_assert(r_type
== elfcpp::R_386_TLS_DESC_CALL
);
2894 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 2);
2895 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2896 view
[0] == 0xff && view
[1] == 0x10);
2902 // Do a relocation in which we convert a TLS_GOTDESC or TLS_DESC_CALL
2903 // General-Dynamic to an Initial-Exec.
2906 Target_i386::Relocate::tls_desc_gd_to_ie(
2907 const Relocate_info
<32, false>* relinfo
,
2910 const elfcpp::Rel
<32, false>& rel
,
2911 unsigned int r_type
,
2912 elfcpp::Elf_types
<32>::Elf_Addr value
,
2913 unsigned char* view
,
2914 section_size_type view_size
)
2916 if (r_type
== elfcpp::R_386_TLS_GOTDESC
)
2918 // leal foo@TLSDESC(%ebx), %eax
2919 // ==> movl foo@GOTNTPOFF(%ebx), %eax
2920 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2921 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
2922 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2923 view
[-2] == 0x8d && view
[-1] == 0x83);
2925 Relocate_functions
<32, false>::rel32(view
, value
);
2929 // call *foo@TLSCALL(%eax)
2931 gold_assert(r_type
== elfcpp::R_386_TLS_DESC_CALL
);
2932 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 2);
2933 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2934 view
[0] == 0xff && view
[1] == 0x10);
2940 // Do a relocation in which we convert a TLS Local-Dynamic to a
2944 Target_i386::Relocate::tls_ld_to_le(const Relocate_info
<32, false>* relinfo
,
2947 const elfcpp::Rel
<32, false>& rel
,
2949 elfcpp::Elf_types
<32>::Elf_Addr
,
2950 unsigned char* view
,
2951 section_size_type view_size
)
2953 // leal foo(%reg), %eax; call ___tls_get_addr
2954 // ==> movl %gs:0,%eax; nop; leal 0(%esi,1),%esi
2956 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
2957 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 9);
2959 // FIXME: Does this test really always pass?
2960 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
2961 view
[-2] == 0x8d && view
[-1] == 0x83);
2963 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), view
[4] == 0xe8);
2965 memcpy(view
- 2, "\x65\xa1\0\0\0\0\x90\x8d\x74\x26\0", 11);
2967 // The next reloc should be a PLT32 reloc against __tls_get_addr.
2969 this->skip_call_tls_get_addr_
= true;
2972 // Do a relocation in which we convert a TLS Initial-Exec to a
2976 Target_i386::Relocate::tls_ie_to_le(const Relocate_info
<32, false>* relinfo
,
2978 Output_segment
* tls_segment
,
2979 const elfcpp::Rel
<32, false>& rel
,
2980 unsigned int r_type
,
2981 elfcpp::Elf_types
<32>::Elf_Addr value
,
2982 unsigned char* view
,
2983 section_size_type view_size
)
2985 // We have to actually change the instructions, which means that we
2986 // need to examine the opcodes to figure out which instruction we
2988 if (r_type
== elfcpp::R_386_TLS_IE
)
2990 // movl %gs:XX,%eax ==> movl $YY,%eax
2991 // movl %gs:XX,%reg ==> movl $YY,%reg
2992 // addl %gs:XX,%reg ==> addl $YY,%reg
2993 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -1);
2994 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
2996 unsigned char op1
= view
[-1];
2999 // movl XX,%eax ==> movl $YY,%eax
3004 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
3006 unsigned char op2
= view
[-2];
3009 // movl XX,%reg ==> movl $YY,%reg
3010 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3011 (op1
& 0xc7) == 0x05);
3013 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
3015 else if (op2
== 0x03)
3017 // addl XX,%reg ==> addl $YY,%reg
3018 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3019 (op1
& 0xc7) == 0x05);
3021 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
3024 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), 0);
3029 // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2
3030 // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2
3031 // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2
3032 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, -2);
3033 tls::check_range(relinfo
, relnum
, rel
.get_r_offset(), view_size
, 4);
3035 unsigned char op1
= view
[-1];
3036 unsigned char op2
= view
[-2];
3037 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(),
3038 (op1
& 0xc0) == 0x80 && (op1
& 7) != 4);
3041 // movl %gs:XX(%reg1),%reg2 ==> movl $YY,%reg2
3043 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
3045 else if (op2
== 0x2b)
3047 // subl %gs:XX(%reg1),%reg2 ==> subl $YY,%reg2
3049 view
[-1] = 0xe8 | ((op1
>> 3) & 7);
3051 else if (op2
== 0x03)
3053 // addl %gs:XX(%reg1),%reg2 ==> addl $YY,$reg2
3055 view
[-1] = 0xc0 | ((op1
>> 3) & 7);
3058 tls::check_tls(relinfo
, relnum
, rel
.get_r_offset(), 0);
3061 value
= tls_segment
->memsz() - value
;
3062 if (r_type
== elfcpp::R_386_TLS_IE
|| r_type
== elfcpp::R_386_TLS_GOTIE
)
3065 Relocate_functions
<32, false>::rel32(view
, value
);
3068 // Relocate section data.
3071 Target_i386::relocate_section(const Relocate_info
<32, false>* relinfo
,
3072 unsigned int sh_type
,
3073 const unsigned char* prelocs
,
3075 Output_section
* output_section
,
3076 bool needs_special_offset_handling
,
3077 unsigned char* view
,
3078 elfcpp::Elf_types
<32>::Elf_Addr address
,
3079 section_size_type view_size
,
3080 const Reloc_symbol_changes
* reloc_symbol_changes
)
3082 gold_assert(sh_type
== elfcpp::SHT_REL
);
3084 gold::relocate_section
<32, false, Target_i386
, elfcpp::SHT_REL
,
3085 Target_i386::Relocate
>(
3091 needs_special_offset_handling
,
3095 reloc_symbol_changes
);
3098 // Return the size of a relocation while scanning during a relocatable
3102 Target_i386::Relocatable_size_for_reloc::get_size_for_reloc(
3103 unsigned int r_type
,
3108 case elfcpp::R_386_NONE
:
3109 case elfcpp::R_386_GNU_VTINHERIT
:
3110 case elfcpp::R_386_GNU_VTENTRY
:
3111 case elfcpp::R_386_TLS_GD
: // Global-dynamic
3112 case elfcpp::R_386_TLS_GOTDESC
: // Global-dynamic (from ~oliva url)
3113 case elfcpp::R_386_TLS_DESC_CALL
:
3114 case elfcpp::R_386_TLS_LDM
: // Local-dynamic
3115 case elfcpp::R_386_TLS_LDO_32
: // Alternate local-dynamic
3116 case elfcpp::R_386_TLS_IE
: // Initial-exec
3117 case elfcpp::R_386_TLS_IE_32
:
3118 case elfcpp::R_386_TLS_GOTIE
:
3119 case elfcpp::R_386_TLS_LE
: // Local-exec
3120 case elfcpp::R_386_TLS_LE_32
:
3123 case elfcpp::R_386_32
:
3124 case elfcpp::R_386_PC32
:
3125 case elfcpp::R_386_GOT32
:
3126 case elfcpp::R_386_PLT32
:
3127 case elfcpp::R_386_GOTOFF
:
3128 case elfcpp::R_386_GOTPC
:
3131 case elfcpp::R_386_16
:
3132 case elfcpp::R_386_PC16
:
3135 case elfcpp::R_386_8
:
3136 case elfcpp::R_386_PC8
:
3139 // These are relocations which should only be seen by the
3140 // dynamic linker, and should never be seen here.
3141 case elfcpp::R_386_COPY
:
3142 case elfcpp::R_386_GLOB_DAT
:
3143 case elfcpp::R_386_JUMP_SLOT
:
3144 case elfcpp::R_386_RELATIVE
:
3145 case elfcpp::R_386_IRELATIVE
:
3146 case elfcpp::R_386_TLS_TPOFF
:
3147 case elfcpp::R_386_TLS_DTPMOD32
:
3148 case elfcpp::R_386_TLS_DTPOFF32
:
3149 case elfcpp::R_386_TLS_TPOFF32
:
3150 case elfcpp::R_386_TLS_DESC
:
3151 object
->error(_("unexpected reloc %u in object file"), r_type
);
3154 case elfcpp::R_386_32PLT
:
3155 case elfcpp::R_386_TLS_GD_32
:
3156 case elfcpp::R_386_TLS_GD_PUSH
:
3157 case elfcpp::R_386_TLS_GD_CALL
:
3158 case elfcpp::R_386_TLS_GD_POP
:
3159 case elfcpp::R_386_TLS_LDM_32
:
3160 case elfcpp::R_386_TLS_LDM_PUSH
:
3161 case elfcpp::R_386_TLS_LDM_CALL
:
3162 case elfcpp::R_386_TLS_LDM_POP
:
3163 case elfcpp::R_386_USED_BY_INTEL_200
:
3165 object
->error(_("unsupported reloc %u in object file"), r_type
);
3170 // Scan the relocs during a relocatable link.
3173 Target_i386::scan_relocatable_relocs(Symbol_table
* symtab
,
3175 Sized_relobj_file
<32, false>* object
,
3176 unsigned int data_shndx
,
3177 unsigned int sh_type
,
3178 const unsigned char* prelocs
,
3180 Output_section
* output_section
,
3181 bool needs_special_offset_handling
,
3182 size_t local_symbol_count
,
3183 const unsigned char* plocal_symbols
,
3184 Relocatable_relocs
* rr
)
3186 gold_assert(sh_type
== elfcpp::SHT_REL
);
3188 typedef gold::Default_scan_relocatable_relocs
<elfcpp::SHT_REL
,
3189 Relocatable_size_for_reloc
> Scan_relocatable_relocs
;
3191 gold::scan_relocatable_relocs
<32, false, elfcpp::SHT_REL
,
3192 Scan_relocatable_relocs
>(
3200 needs_special_offset_handling
,
3206 // Relocate a section during a relocatable link.
3209 Target_i386::relocate_for_relocatable(
3210 const Relocate_info
<32, false>* relinfo
,
3211 unsigned int sh_type
,
3212 const unsigned char* prelocs
,
3214 Output_section
* output_section
,
3215 off_t offset_in_output_section
,
3216 const Relocatable_relocs
* rr
,
3217 unsigned char* view
,
3218 elfcpp::Elf_types
<32>::Elf_Addr view_address
,
3219 section_size_type view_size
,
3220 unsigned char* reloc_view
,
3221 section_size_type reloc_view_size
)
3223 gold_assert(sh_type
== elfcpp::SHT_REL
);
3225 gold::relocate_for_relocatable
<32, false, elfcpp::SHT_REL
>(
3230 offset_in_output_section
,
3239 // Return the value to use for a dynamic which requires special
3240 // treatment. This is how we support equality comparisons of function
3241 // pointers across shared library boundaries, as described in the
3242 // processor specific ABI supplement.
3245 Target_i386::do_dynsym_value(const Symbol
* gsym
) const
3247 gold_assert(gsym
->is_from_dynobj() && gsym
->has_plt_offset());
3248 return this->plt_section()->address() + gsym
->plt_offset();
3251 // Return a string used to fill a code section with nops to take up
3252 // the specified length.
3255 Target_i386::do_code_fill(section_size_type length
) const
3259 // Build a jmp instruction to skip over the bytes.
3260 unsigned char jmp
[5];
3262 elfcpp::Swap_unaligned
<32, false>::writeval(jmp
+ 1, length
- 5);
3263 return (std::string(reinterpret_cast<char*>(&jmp
[0]), 5)
3264 + std::string(length
- 5, '\0'));
3267 // Nop sequences of various lengths.
3268 const char nop1
[1] = { 0x90 }; // nop
3269 const char nop2
[2] = { 0x66, 0x90 }; // xchg %ax %ax
3270 const char nop3
[3] = { 0x8d, 0x76, 0x00 }; // leal 0(%esi),%esi
3271 const char nop4
[4] = { 0x8d, 0x74, 0x26, 0x00}; // leal 0(%esi,1),%esi
3272 const char nop5
[5] = { 0x90, 0x8d, 0x74, 0x26, // nop
3273 0x00 }; // leal 0(%esi,1),%esi
3274 const char nop6
[6] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
3276 const char nop7
[7] = { 0x8d, 0xb4, 0x26, 0x00, // leal 0L(%esi,1),%esi
3278 const char nop8
[8] = { 0x90, 0x8d, 0xb4, 0x26, // nop
3279 0x00, 0x00, 0x00, 0x00 }; // leal 0L(%esi,1),%esi
3280 const char nop9
[9] = { 0x89, 0xf6, 0x8d, 0xbc, // movl %esi,%esi
3281 0x27, 0x00, 0x00, 0x00, // leal 0L(%edi,1),%edi
3283 const char nop10
[10] = { 0x8d, 0x76, 0x00, 0x8d, // leal 0(%esi),%esi
3284 0xbc, 0x27, 0x00, 0x00, // leal 0L(%edi,1),%edi
3286 const char nop11
[11] = { 0x8d, 0x74, 0x26, 0x00, // leal 0(%esi,1),%esi
3287 0x8d, 0xbc, 0x27, 0x00, // leal 0L(%edi,1),%edi
3289 const char nop12
[12] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
3290 0x00, 0x00, 0x8d, 0xbf, // leal 0L(%edi),%edi
3291 0x00, 0x00, 0x00, 0x00 };
3292 const char nop13
[13] = { 0x8d, 0xb6, 0x00, 0x00, // leal 0L(%esi),%esi
3293 0x00, 0x00, 0x8d, 0xbc, // leal 0L(%edi,1),%edi
3294 0x27, 0x00, 0x00, 0x00,
3296 const char nop14
[14] = { 0x8d, 0xb4, 0x26, 0x00, // leal 0L(%esi,1),%esi
3297 0x00, 0x00, 0x00, 0x8d, // leal 0L(%edi,1),%edi
3298 0xbc, 0x27, 0x00, 0x00,
3300 const char nop15
[15] = { 0xeb, 0x0d, 0x90, 0x90, // jmp .+15
3301 0x90, 0x90, 0x90, 0x90, // nop,nop,nop,...
3302 0x90, 0x90, 0x90, 0x90,
3305 const char* nops
[16] = {
3307 nop1
, nop2
, nop3
, nop4
, nop5
, nop6
, nop7
,
3308 nop8
, nop9
, nop10
, nop11
, nop12
, nop13
, nop14
, nop15
3311 return std::string(nops
[length
], length
);
3314 // Return the value to use for the base of a DW_EH_PE_datarel offset
3315 // in an FDE. Solaris and SVR4 use DW_EH_PE_datarel because their
3316 // assembler can not write out the difference between two labels in
3317 // different sections, so instead of using a pc-relative value they
3318 // use an offset from the GOT.
3321 Target_i386::do_ehframe_datarel_base() const
3323 gold_assert(this->global_offset_table_
!= NULL
);
3324 Symbol
* sym
= this->global_offset_table_
;
3325 Sized_symbol
<32>* ssym
= static_cast<Sized_symbol
<32>*>(sym
);
3326 return ssym
->value();
3329 // Return whether SYM should be treated as a call to a non-split
3330 // function. We don't want that to be true of a call to a
3331 // get_pc_thunk function.
3334 Target_i386::do_is_call_to_non_split(const Symbol
* sym
, unsigned int) const
3336 return (sym
->type() == elfcpp::STT_FUNC
3337 && !is_prefix_of("__i686.get_pc_thunk.", sym
->name()));
3340 // FNOFFSET in section SHNDX in OBJECT is the start of a function
3341 // compiled with -fsplit-stack. The function calls non-split-stack
3342 // code. We have to change the function so that it always ensures
3343 // that it has enough stack space to run some random function.
3346 Target_i386::do_calls_non_split(Relobj
* object
, unsigned int shndx
,
3347 section_offset_type fnoffset
,
3348 section_size_type fnsize
,
3349 unsigned char* view
,
3350 section_size_type view_size
,
3352 std::string
* to
) const
3354 // The function starts with a comparison of the stack pointer and a
3355 // field in the TCB. This is followed by a jump.
3358 if (this->match_view(view
, view_size
, fnoffset
, "\x65\x3b\x25", 3)
3361 // We will call __morestack if the carry flag is set after this
3362 // comparison. We turn the comparison into an stc instruction
3364 view
[fnoffset
] = '\xf9';
3365 this->set_view_to_nop(view
, view_size
, fnoffset
+ 1, 6);
3367 // lea NN(%esp),%ecx
3368 // lea NN(%esp),%edx
3369 else if ((this->match_view(view
, view_size
, fnoffset
, "\x8d\x8c\x24", 3)
3370 || this->match_view(view
, view_size
, fnoffset
, "\x8d\x94\x24", 3))
3373 // This is loading an offset from the stack pointer for a
3374 // comparison. The offset is negative, so we decrease the
3375 // offset by the amount of space we need for the stack. This
3376 // means we will avoid calling __morestack if there happens to
3377 // be plenty of space on the stack already.
3378 unsigned char* pval
= view
+ fnoffset
+ 3;
3379 uint32_t val
= elfcpp::Swap_unaligned
<32, false>::readval(pval
);
3380 val
-= parameters
->options().split_stack_adjust_size();
3381 elfcpp::Swap_unaligned
<32, false>::writeval(pval
, val
);
3385 if (!object
->has_no_split_stack())
3386 object
->error(_("failed to match split-stack sequence at "
3387 "section %u offset %0zx"),
3388 shndx
, static_cast<size_t>(fnoffset
));
3392 // We have to change the function so that it calls
3393 // __morestack_non_split instead of __morestack. The former will
3394 // allocate additional stack space.
3395 *from
= "__morestack";
3396 *to
= "__morestack_non_split";
3399 // The selector for i386 object files.
3401 class Target_selector_i386
: public Target_selector_freebsd
3404 Target_selector_i386()
3405 : Target_selector_freebsd(elfcpp::EM_386
, 32, false,
3406 "elf32-i386", "elf32-i386-freebsd",
3411 do_instantiate_target()
3412 { return new Target_i386(); }
3415 Target_selector_i386 target_selector_i386
;
3417 } // End anonymous namespace.