1 // object.h -- support for an object file for linking in gold -*- C++ -*-
3 // Copyright 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013
4 // Free Software Foundation, Inc.
5 // Written by Ian Lance Taylor <iant@google.com>.
7 // This file is part of gold.
9 // This program is free software; you can redistribute it and/or modify
10 // it under the terms of the GNU General Public License as published by
11 // the Free Software Foundation; either version 3 of the License, or
12 // (at your option) any later version.
14 // This program is distributed in the hope that it will be useful,
15 // but WITHOUT ANY WARRANTY; without even the implied warranty of
16 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 // GNU General Public License for more details.
19 // You should have received a copy of the GNU General Public License
20 // along with this program; if not, write to the Free Software
21 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
22 // MA 02110-1301, USA.
31 #include "elfcpp_file.h"
39 class General_options
;
46 class Output_symtab_xindex
;
49 class Object_merge_map
;
50 class Relocatable_relocs
;
53 template<typename Stringpool_char
>
54 class Stringpool_template
;
56 // Data to pass from read_symbols() to add_symbols().
58 struct Read_symbols_data
61 : section_headers(NULL
), section_names(NULL
), symbols(NULL
),
62 symbol_names(NULL
), versym(NULL
), verdef(NULL
), verneed(NULL
)
68 File_view
* section_headers
;
70 File_view
* section_names
;
71 // Size of section name data in bytes.
72 section_size_type section_names_size
;
75 // Size of symbol data in bytes.
76 section_size_type symbols_size
;
77 // Offset of external symbols within symbol data. This structure
78 // sometimes contains only external symbols, in which case this will
79 // be zero. Sometimes it contains all symbols.
80 section_offset_type external_symbols_offset
;
82 File_view
* symbol_names
;
83 // Size of symbol name data in bytes.
84 section_size_type symbol_names_size
;
86 // Version information. This is only used on dynamic objects.
87 // Version symbol data (from SHT_GNU_versym section).
89 section_size_type versym_size
;
90 // Version definition data (from SHT_GNU_verdef section).
92 section_size_type verdef_size
;
93 unsigned int verdef_info
;
94 // Needed version data (from SHT_GNU_verneed section).
96 section_size_type verneed_size
;
97 unsigned int verneed_info
;
100 // Information used to print error messages.
102 struct Symbol_location_info
104 std::string source_file
;
105 std::string enclosing_symbol_name
;
106 elfcpp::STT enclosing_symbol_type
;
109 // Data about a single relocation section. This is read in
110 // read_relocs and processed in scan_relocs.
112 struct Section_relocs
119 { delete this->contents
; }
121 // Index of reloc section.
122 unsigned int reloc_shndx
;
123 // Index of section that relocs apply to.
124 unsigned int data_shndx
;
125 // Contents of reloc section.
127 // Reloc section type.
128 unsigned int sh_type
;
129 // Number of reloc entries.
132 Output_section
* output_section
;
133 // Whether this section has special handling for offsets.
134 bool needs_special_offset_handling
;
135 // Whether the data section is allocated (has the SHF_ALLOC flag set).
136 bool is_data_section_allocated
;
139 // Relocations in an object file. This is read in read_relocs and
140 // processed in scan_relocs.
142 struct Read_relocs_data
145 : local_symbols(NULL
)
149 { delete this->local_symbols
; }
151 typedef std::vector
<Section_relocs
> Relocs_list
;
154 // The local symbols.
155 File_view
* local_symbols
;
158 // The Xindex class manages section indexes for objects with more than
164 Xindex(int large_shndx_offset
)
165 : large_shndx_offset_(large_shndx_offset
), symtab_xindex_()
168 // Initialize the symtab_xindex_ array, given the object and the
169 // section index of the symbol table to use.
170 template<int size
, bool big_endian
>
172 initialize_symtab_xindex(Object
*, unsigned int symtab_shndx
);
174 // Read in the symtab_xindex_ array, given its section index.
175 // PSHDRS may optionally point to the section headers.
176 template<int size
, bool big_endian
>
178 read_symtab_xindex(Object
*, unsigned int xindex_shndx
,
179 const unsigned char* pshdrs
);
181 // Symbol SYMNDX in OBJECT has a section of SHN_XINDEX; return the
182 // real section index.
184 sym_xindex_to_shndx(Object
* object
, unsigned int symndx
);
187 // The type of the array giving the real section index for symbols
188 // whose st_shndx field holds SHN_XINDEX.
189 typedef std::vector
<unsigned int> Symtab_xindex
;
191 // Adjust a section index if necessary. This should only be called
192 // for ordinary section indexes.
194 adjust_shndx(unsigned int shndx
)
196 if (shndx
>= elfcpp::SHN_LORESERVE
)
197 shndx
+= this->large_shndx_offset_
;
201 // Adjust to apply to large section indexes.
202 int large_shndx_offset_
;
203 // The data from the SHT_SYMTAB_SHNDX section.
204 Symtab_xindex symtab_xindex_
;
207 // A GOT offset list. A symbol may have more than one GOT offset
208 // (e.g., when mixing modules compiled with two different TLS models),
209 // but will usually have at most one. GOT_TYPE identifies the type of
210 // GOT entry; its values are specific to each target.
212 class Got_offset_list
216 : got_type_(-1U), got_offset_(0), got_next_(NULL
)
219 Got_offset_list(unsigned int got_type
, unsigned int got_offset
)
220 : got_type_(got_type
), got_offset_(got_offset
), got_next_(NULL
)
225 if (this->got_next_
!= NULL
)
227 delete this->got_next_
;
228 this->got_next_
= NULL
;
232 // Initialize the fields to their default values.
236 this->got_type_
= -1U;
237 this->got_offset_
= 0;
238 this->got_next_
= NULL
;
241 // Set the offset for the GOT entry of type GOT_TYPE.
243 set_offset(unsigned int got_type
, unsigned int got_offset
)
245 if (this->got_type_
== -1U)
247 this->got_type_
= got_type
;
248 this->got_offset_
= got_offset
;
252 for (Got_offset_list
* g
= this; g
!= NULL
; g
= g
->got_next_
)
254 if (g
->got_type_
== got_type
)
256 g
->got_offset_
= got_offset
;
260 Got_offset_list
* g
= new Got_offset_list(got_type
, got_offset
);
261 g
->got_next_
= this->got_next_
;
266 // Return the offset for a GOT entry of type GOT_TYPE.
268 get_offset(unsigned int got_type
) const
270 for (const Got_offset_list
* g
= this; g
!= NULL
; g
= g
->got_next_
)
272 if (g
->got_type_
== got_type
)
273 return g
->got_offset_
;
278 // Return a pointer to the list, or NULL if the list is empty.
279 const Got_offset_list
*
282 if (this->got_type_
== -1U)
287 // Abstract visitor class for iterating over GOT offsets.
299 visit(unsigned int, unsigned int) = 0;
302 // Loop over all GOT offset entries, calling a visitor class V for each.
304 for_all_got_offsets(Visitor
* v
) const
306 if (this->got_type_
== -1U)
308 for (const Got_offset_list
* g
= this; g
!= NULL
; g
= g
->got_next_
)
309 v
->visit(g
->got_type_
, g
->got_offset_
);
313 unsigned int got_type_
;
314 unsigned int got_offset_
;
315 Got_offset_list
* got_next_
;
318 // Object is an abstract base class which represents either a 32-bit
319 // or a 64-bit input object. This can be a regular object file
320 // (ET_REL) or a shared object (ET_DYN).
325 typedef std::vector
<Symbol
*> Symbols
;
327 // NAME is the name of the object as we would report it to the user
328 // (e.g., libfoo.a(bar.o) if this is in an archive. INPUT_FILE is
329 // used to read the file. OFFSET is the offset within the input
330 // file--0 for a .o or .so file, something else for a .a file.
331 Object(const std::string
& name
, Input_file
* input_file
, bool is_dynamic
,
333 : name_(name
), input_file_(input_file
), offset_(offset
), shnum_(-1U),
334 is_dynamic_(is_dynamic
), is_needed_(false), uses_split_stack_(false),
335 has_no_split_stack_(false), no_export_(false),
336 is_in_system_directory_(false), as_needed_(false), xindex_(NULL
)
338 if (input_file
!= NULL
)
340 input_file
->file().add_object();
341 this->is_in_system_directory_
= input_file
->is_in_system_directory();
342 this->as_needed_
= input_file
->options().as_needed();
348 if (this->input_file_
!= NULL
)
349 this->input_file_
->file().remove_object();
352 // Return the name of the object as we would report it to the user.
355 { return this->name_
; }
357 // Get the offset into the file.
360 { return this->offset_
; }
362 // Return whether this is a dynamic object.
365 { return this->is_dynamic_
; }
367 // Return whether this object is needed--true if it is a dynamic
368 // object which defines some symbol referenced by a regular object.
369 // We keep the flag here rather than in Dynobj for convenience when
373 { return this->is_needed_
; }
375 // Record that this object is needed.
378 { this->is_needed_
= true; }
380 // Return whether this object was compiled with -fsplit-stack.
382 uses_split_stack() const
383 { return this->uses_split_stack_
; }
385 // Return whether this object contains any functions compiled with
386 // the no_split_stack attribute.
388 has_no_split_stack() const
389 { return this->has_no_split_stack_
; }
391 // Returns NULL for Objects that are not dynamic objects. This method
392 // is overridden in the Dynobj class.
395 { return this->do_dynobj(); }
397 // Returns NULL for Objects that are not plugin objects. This method
398 // is overridden in the Pluginobj class.
401 { return this->do_pluginobj(); }
403 // Get the file. We pass on const-ness.
407 gold_assert(this->input_file_
!= NULL
);
408 return this->input_file_
;
414 gold_assert(this->input_file_
!= NULL
);
415 return this->input_file_
;
418 // Lock the underlying file.
422 if (this->input_file_
!= NULL
)
423 this->input_file_
->file().lock(t
);
426 // Unlock the underlying file.
428 unlock(const Task
* t
)
430 if (this->input_file_
!= NULL
)
431 this->input_file()->file().unlock(t
);
434 // Return whether the underlying file is locked.
437 { return this->input_file_
!= NULL
&& this->input_file_
->file().is_locked(); }
439 // Return the token, so that the task can be queued.
443 if (this->input_file_
== NULL
)
445 return this->input_file()->file().token();
448 // Release the underlying file.
452 if (this->input_file_
!= NULL
)
453 this->input_file()->file().release();
456 // Return whether we should just read symbols from this file.
459 { return this->input_file()->just_symbols(); }
461 // Return whether this is an incremental object.
463 is_incremental() const
464 { return this->do_is_incremental(); }
466 // Return the last modified time of the file.
469 { return this->do_get_mtime(); }
471 // Get the number of sections.
474 { return this->shnum_
; }
476 // Return a view of the contents of a section. Set *PLEN to the
477 // size. CACHE is a hint as in File_read::get_view.
479 section_contents(unsigned int shndx
, section_size_type
* plen
, bool cache
);
481 // Adjust a symbol's section index as needed. SYMNDX is the index
482 // of the symbol and SHNDX is the symbol's section from
483 // get_st_shndx. This returns the section index. It sets
484 // *IS_ORDINARY to indicate whether this is a normal section index,
485 // rather than a special code between SHN_LORESERVE and
488 adjust_sym_shndx(unsigned int symndx
, unsigned int shndx
, bool* is_ordinary
)
490 if (shndx
< elfcpp::SHN_LORESERVE
)
492 else if (shndx
== elfcpp::SHN_XINDEX
)
494 if (this->xindex_
== NULL
)
495 this->xindex_
= this->do_initialize_xindex();
496 shndx
= this->xindex_
->sym_xindex_to_shndx(this, symndx
);
500 *is_ordinary
= false;
504 // Return the size of a section given a section index.
506 section_size(unsigned int shndx
)
507 { return this->do_section_size(shndx
); }
509 // Return the name of a section given a section index.
511 section_name(unsigned int shndx
)
512 { return this->do_section_name(shndx
); }
514 // Return the section flags given a section index.
516 section_flags(unsigned int shndx
)
517 { return this->do_section_flags(shndx
); }
519 // Return the section entsize given a section index.
521 section_entsize(unsigned int shndx
)
522 { return this->do_section_entsize(shndx
); }
524 // Return the section address given a section index.
526 section_address(unsigned int shndx
)
527 { return this->do_section_address(shndx
); }
529 // Return the section type given a section index.
531 section_type(unsigned int shndx
)
532 { return this->do_section_type(shndx
); }
534 // Return the section link field given a section index.
536 section_link(unsigned int shndx
)
537 { return this->do_section_link(shndx
); }
539 // Return the section info field given a section index.
541 section_info(unsigned int shndx
)
542 { return this->do_section_info(shndx
); }
544 // Return the required section alignment given a section index.
546 section_addralign(unsigned int shndx
)
547 { return this->do_section_addralign(shndx
); }
549 // Return the output section given a section index.
551 output_section(unsigned int shndx
) const
552 { return this->do_output_section(shndx
); }
554 // Given a section index, return its address.
555 // The return value will be -1U if the section is specially mapped,
556 // such as a merge section.
558 output_section_address(unsigned int shndx
)
559 { return this->do_output_section_address(shndx
); }
561 // Given a section index, return the offset in the Output_section.
562 // The return value will be -1U if the section is specially mapped,
563 // such as a merge section.
565 output_section_offset(unsigned int shndx
) const
566 { return this->do_output_section_offset(shndx
); }
568 // Read the symbol information.
570 read_symbols(Read_symbols_data
* sd
)
571 { return this->do_read_symbols(sd
); }
573 // Pass sections which should be included in the link to the Layout
574 // object, and record where the sections go in the output file.
576 layout(Symbol_table
* symtab
, Layout
* layout
, Read_symbols_data
* sd
)
577 { this->do_layout(symtab
, layout
, sd
); }
579 // Add symbol information to the global symbol table.
581 add_symbols(Symbol_table
* symtab
, Read_symbols_data
* sd
, Layout
*layout
)
582 { this->do_add_symbols(symtab
, sd
, layout
); }
584 // Add symbol information to the global symbol table.
585 Archive::Should_include
586 should_include_member(Symbol_table
* symtab
, Layout
* layout
,
587 Read_symbols_data
* sd
, std::string
* why
)
588 { return this->do_should_include_member(symtab
, layout
, sd
, why
); }
590 // Iterate over global symbols, calling a visitor class V for each.
592 for_all_global_symbols(Read_symbols_data
* sd
,
593 Library_base::Symbol_visitor_base
* v
)
594 { return this->do_for_all_global_symbols(sd
, v
); }
596 // Iterate over local symbols, calling a visitor class V for each GOT offset
597 // associated with a local symbol.
599 for_all_local_got_entries(Got_offset_list::Visitor
* v
) const
600 { this->do_for_all_local_got_entries(v
); }
602 // Functions and types for the elfcpp::Elf_file interface. This
603 // permit us to use Object as the File template parameter for
606 // The View class is returned by view. It must support a single
607 // method, data(). This is trivial, because get_view does what we
612 View(const unsigned char* p
)
621 const unsigned char* p_
;
626 view(off_t file_offset
, section_size_type data_size
)
627 { return View(this->get_view(file_offset
, data_size
, true, true)); }
631 error(const char* format
, ...) const ATTRIBUTE_PRINTF_2
;
633 // A location in the file.
639 Location(off_t fo
, section_size_type ds
)
640 : file_offset(fo
), data_size(ds
)
644 // Get a View given a Location.
645 View
view(Location loc
)
646 { return View(this->get_view(loc
.file_offset
, loc
.data_size
, true, true)); }
648 // Get a view into the underlying file.
650 get_view(off_t start
, section_size_type size
, bool aligned
, bool cache
)
652 return this->input_file()->file().get_view(this->offset_
, start
, size
,
656 // Get a lasting view into the underlying file.
658 get_lasting_view(off_t start
, section_size_type size
, bool aligned
,
661 return this->input_file()->file().get_lasting_view(this->offset_
, start
,
662 size
, aligned
, cache
);
665 // Read data from the underlying file.
667 read(off_t start
, section_size_type size
, void* p
)
668 { this->input_file()->file().read(start
+ this->offset_
, size
, p
); }
670 // Read multiple data from the underlying file.
672 read_multiple(const File_read::Read_multiple
& rm
)
673 { this->input_file()->file().read_multiple(this->offset_
, rm
); }
675 // Stop caching views in the underlying file.
677 clear_view_cache_marks()
679 if (this->input_file_
!= NULL
)
680 this->input_file_
->file().clear_view_cache_marks();
683 // Get the number of global symbols defined by this object, and the
684 // number of the symbols whose final definition came from this
687 get_global_symbol_counts(const Symbol_table
* symtab
, size_t* defined
,
689 { this->do_get_global_symbol_counts(symtab
, defined
, used
); }
691 // Get the symbols defined in this object.
693 get_global_symbols() const
694 { return this->do_get_global_symbols(); }
696 // Set flag that this object was found in a system directory.
698 set_is_in_system_directory()
699 { this->is_in_system_directory_
= true; }
701 // Return whether this object was found in a system directory.
703 is_in_system_directory() const
704 { return this->is_in_system_directory_
; }
706 // Set flag that this object was linked with --as-needed.
709 { this->as_needed_
= true; }
711 // Return whether this object was linked with --as-needed.
714 { return this->as_needed_
; }
716 // Return whether we found this object by searching a directory.
719 { return this->input_file()->will_search_for(); }
723 { return this->no_export_
; }
726 set_no_export(bool value
)
727 { this->no_export_
= value
; }
729 // Return TRUE if the section is a compressed debug section, and set
730 // *UNCOMPRESSED_SIZE to the size of the uncompressed data.
732 section_is_compressed(unsigned int shndx
,
733 section_size_type
* uncompressed_size
) const
734 { return this->do_section_is_compressed(shndx
, uncompressed_size
); }
736 // Return a view of the decompressed contents of a section. Set *PLEN
737 // to the size. Set *IS_NEW to true if the contents need to be freed
740 decompressed_section_contents(unsigned int shndx
, section_size_type
* plen
,
742 { return this->do_decompressed_section_contents(shndx
, plen
, is_cached
); }
744 // Discard any buffers of decompressed sections. This is done
745 // at the end of the Add_symbols task.
747 discard_decompressed_sections()
748 { this->do_discard_decompressed_sections(); }
750 // Return the index of the first incremental relocation for symbol SYMNDX.
752 get_incremental_reloc_base(unsigned int symndx
) const
753 { return this->do_get_incremental_reloc_base(symndx
); }
755 // Return the number of incremental relocations for symbol SYMNDX.
757 get_incremental_reloc_count(unsigned int symndx
) const
758 { return this->do_get_incremental_reloc_count(symndx
); }
761 // Returns NULL for Objects that are not dynamic objects. This method
762 // is overridden in the Dynobj class.
767 // Returns NULL for Objects that are not plugin objects. This method
768 // is overridden in the Pluginobj class.
773 // Return TRUE if this is an incremental (unchanged) input file.
774 // We return FALSE by default; the incremental object classes
775 // override this method.
777 do_is_incremental() const
780 // Return the last modified time of the file. This method may be
781 // overridden for subclasses that don't use an actual file (e.g.,
782 // Incremental objects).
785 { return this->input_file()->file().get_mtime(); }
787 // Read the symbols--implemented by child class.
789 do_read_symbols(Read_symbols_data
*) = 0;
791 // Lay out sections--implemented by child class.
793 do_layout(Symbol_table
*, Layout
*, Read_symbols_data
*) = 0;
795 // Add symbol information to the global symbol table--implemented by
798 do_add_symbols(Symbol_table
*, Read_symbols_data
*, Layout
*) = 0;
800 virtual Archive::Should_include
801 do_should_include_member(Symbol_table
* symtab
, Layout
*, Read_symbols_data
*,
802 std::string
* why
) = 0;
804 // Iterate over global symbols, calling a visitor class V for each.
806 do_for_all_global_symbols(Read_symbols_data
* sd
,
807 Library_base::Symbol_visitor_base
* v
) = 0;
809 // Iterate over local symbols, calling a visitor class V for each GOT offset
810 // associated with a local symbol.
812 do_for_all_local_got_entries(Got_offset_list::Visitor
* v
) const = 0;
814 // Return the location of the contents of a section. Implemented by
816 virtual const unsigned char*
817 do_section_contents(unsigned int shndx
, section_size_type
* plen
,
820 // Get the size of a section--implemented by child class.
822 do_section_size(unsigned int shndx
) = 0;
824 // Get the name of a section--implemented by child class.
826 do_section_name(unsigned int shndx
) = 0;
828 // Get section flags--implemented by child class.
830 do_section_flags(unsigned int shndx
) = 0;
832 // Get section entsize--implemented by child class.
834 do_section_entsize(unsigned int shndx
) = 0;
836 // Get section address--implemented by child class.
838 do_section_address(unsigned int shndx
) = 0;
840 // Get section type--implemented by child class.
842 do_section_type(unsigned int shndx
) = 0;
844 // Get section link field--implemented by child class.
846 do_section_link(unsigned int shndx
) = 0;
848 // Get section info field--implemented by child class.
850 do_section_info(unsigned int shndx
) = 0;
852 // Get section alignment--implemented by child class.
854 do_section_addralign(unsigned int shndx
) = 0;
856 // Return the output section given a section index--implemented
858 virtual Output_section
*
859 do_output_section(unsigned int) const
860 { gold_unreachable(); }
862 // Get the address of a section--implemented by child class.
864 do_output_section_address(unsigned int)
865 { gold_unreachable(); }
867 // Get the offset of a section--implemented by child class.
869 do_output_section_offset(unsigned int) const
870 { gold_unreachable(); }
872 // Return the Xindex structure to use.
874 do_initialize_xindex() = 0;
876 // Implement get_global_symbol_counts--implemented by child class.
878 do_get_global_symbol_counts(const Symbol_table
*, size_t*, size_t*) const = 0;
880 virtual const Symbols
*
881 do_get_global_symbols() const = 0;
883 // Set the number of sections.
886 { this->shnum_
= shnum
; }
888 // Functions used by both Sized_relobj_file and Sized_dynobj.
890 // Read the section data into a Read_symbols_data object.
891 template<int size
, bool big_endian
>
893 read_section_data(elfcpp::Elf_file
<size
, big_endian
, Object
>*,
896 // Find the section header with the given NAME. If HDR is non-NULL
897 // then it is a section header returned from a previous call to this
898 // function and the next section header with the same name will be
900 template<int size
, bool big_endian
>
902 find_shdr(const unsigned char* pshdrs
, const char* name
,
903 const char* names
, section_size_type names_size
,
904 const unsigned char* hdr
) const;
906 // Let the child class initialize the xindex object directly.
908 set_xindex(Xindex
* xindex
)
910 gold_assert(this->xindex_
== NULL
);
911 this->xindex_
= xindex
;
914 // If NAME is the name of a special .gnu.warning section, arrange
915 // for the warning to be issued. SHNDX is the section index.
916 // Return whether it is a warning section.
918 handle_gnu_warning_section(const char* name
, unsigned int shndx
,
921 // If NAME is the name of the special section which indicates that
922 // this object was compiled with -fsplit-stack, mark it accordingly,
923 // and return true. Otherwise return false.
925 handle_split_stack_section(const char* name
);
927 // Return TRUE if the section is a compressed debug section, and set
928 // *UNCOMPRESSED_SIZE to the size of the uncompressed data.
930 do_section_is_compressed(unsigned int, section_size_type
*) const
933 // Return a view of the decompressed contents of a section. Set *PLEN
934 // to the size. This default implementation simply returns the
935 // raw section contents and sets *IS_NEW to false to indicate
936 // that the contents do not need to be freed by the caller.
937 // This function must be overridden for any types of object files
938 // that might contain compressed sections.
939 virtual const unsigned char*
940 do_decompressed_section_contents(unsigned int shndx
,
941 section_size_type
* plen
,
945 return this->do_section_contents(shndx
, plen
, false);
948 // Discard any buffers of decompressed sections. This is done
949 // at the end of the Add_symbols task.
951 do_discard_decompressed_sections()
954 // Return the index of the first incremental relocation for symbol SYMNDX--
955 // implemented by child class.
957 do_get_incremental_reloc_base(unsigned int) const
958 { gold_unreachable(); }
960 // Return the number of incremental relocations for symbol SYMNDX--
961 // implemented by child class.
963 do_get_incremental_reloc_count(unsigned int) const
964 { gold_unreachable(); }
967 // This class may not be copied.
968 Object(const Object
&);
969 Object
& operator=(const Object
&);
971 // Name of object as printed to user.
973 // For reading the file.
974 Input_file
* input_file_
;
975 // Offset within the file--0 for an object file, non-0 for an
978 // Number of input sections.
980 // Whether this is a dynamic object.
981 bool is_dynamic_
: 1;
982 // Whether this object is needed. This is only set for dynamic
983 // objects, and means that the object defined a symbol which was
984 // used by a reference from a regular object.
986 // Whether this object was compiled with -fsplit-stack.
987 bool uses_split_stack_
: 1;
988 // Whether this object contains any functions compiled with the
989 // no_split_stack attribute.
990 bool has_no_split_stack_
: 1;
991 // True if exclude this object from automatic symbol export.
992 // This is used only for archive objects.
994 // True if the object was found in a system directory.
995 bool is_in_system_directory_
: 1;
996 // True if the object was linked with --as-needed.
998 // Many sections for objects with more than SHN_LORESERVE sections.
1002 // A regular object (ET_REL). This is an abstract base class itself.
1003 // The implementation is the template class Sized_relobj_file.
1005 class Relobj
: public Object
1008 Relobj(const std::string
& name
, Input_file
* input_file
, off_t offset
= 0)
1009 : Object(name
, input_file
, false, offset
),
1011 map_to_relocatable_relocs_(NULL
),
1012 object_merge_map_(NULL
),
1013 relocs_must_follow_section_writes_(false),
1015 reloc_counts_(NULL
),
1017 first_dyn_reloc_(0),
1021 // During garbage collection, the Read_symbols_data pass for
1022 // each object is stored as layout needs to be done after
1023 // reloc processing.
1026 { return this->sd_
; }
1028 // Decides which section names have to be included in the worklist
1031 is_section_name_included(const char* name
);
1034 copy_symbols_data(Symbols_data
* gc_sd
, Read_symbols_data
* sd
,
1035 unsigned int section_header_size
);
1038 set_symbols_data(Symbols_data
* sd
)
1041 // During garbage collection, the Read_relocs pass for all objects
1042 // is done before scanning the relocs. In that case, this->rd_ is
1043 // used to store the information from Read_relocs for each object.
1044 // This data is also used to compute the list of relevant sections.
1047 { return this->rd_
; }
1050 set_relocs_data(Read_relocs_data
* rd
)
1054 is_output_section_offset_invalid(unsigned int shndx
) const = 0;
1058 read_relocs(Read_relocs_data
* rd
)
1059 { return this->do_read_relocs(rd
); }
1061 // Process the relocs, during garbage collection only.
1063 gc_process_relocs(Symbol_table
* symtab
, Layout
* layout
, Read_relocs_data
* rd
)
1064 { return this->do_gc_process_relocs(symtab
, layout
, rd
); }
1066 // Scan the relocs and adjust the symbol table.
1068 scan_relocs(Symbol_table
* symtab
, Layout
* layout
, Read_relocs_data
* rd
)
1069 { return this->do_scan_relocs(symtab
, layout
, rd
); }
1071 // Return the value of the local symbol whose index is SYMNDX, plus
1072 // ADDEND. ADDEND is passed in so that we can correctly handle the
1073 // section symbol for a merge section.
1075 local_symbol_value(unsigned int symndx
, uint64_t addend
) const
1076 { return this->do_local_symbol_value(symndx
, addend
); }
1078 // Return the PLT offset for a local symbol. It is an error to call
1079 // this if it doesn't have one.
1081 local_plt_offset(unsigned int symndx
) const
1082 { return this->do_local_plt_offset(symndx
); }
1084 // Return whether the local symbol SYMNDX has a GOT offset of type
1087 local_has_got_offset(unsigned int symndx
, unsigned int got_type
) const
1088 { return this->do_local_has_got_offset(symndx
, got_type
); }
1090 // Return the GOT offset of type GOT_TYPE of the local symbol
1091 // SYMNDX. It is an error to call this if the symbol does not have
1092 // a GOT offset of the specified type.
1094 local_got_offset(unsigned int symndx
, unsigned int got_type
) const
1095 { return this->do_local_got_offset(symndx
, got_type
); }
1097 // Set the GOT offset with type GOT_TYPE of the local symbol SYMNDX
1100 set_local_got_offset(unsigned int symndx
, unsigned int got_type
,
1101 unsigned int got_offset
)
1102 { this->do_set_local_got_offset(symndx
, got_type
, got_offset
); }
1104 // Return whether the local symbol SYMNDX is a TLS symbol.
1106 local_is_tls(unsigned int symndx
) const
1107 { return this->do_local_is_tls(symndx
); }
1109 // The number of local symbols in the input symbol table.
1110 virtual unsigned int
1111 local_symbol_count() const
1112 { return this->do_local_symbol_count(); }
1114 // The number of local symbols in the output symbol table.
1115 virtual unsigned int
1116 output_local_symbol_count() const
1117 { return this->do_output_local_symbol_count(); }
1119 // The file offset for local symbols in the output symbol table.
1121 local_symbol_offset() const
1122 { return this->do_local_symbol_offset(); }
1124 // Initial local symbol processing: count the number of local symbols
1125 // in the output symbol table and dynamic symbol table; add local symbol
1126 // names to *POOL and *DYNPOOL.
1128 count_local_symbols(Stringpool_template
<char>* pool
,
1129 Stringpool_template
<char>* dynpool
)
1130 { return this->do_count_local_symbols(pool
, dynpool
); }
1132 // Set the values of the local symbols, set the output symbol table
1133 // indexes for the local variables, and set the offset where local
1134 // symbol information will be stored. Returns the new local symbol index.
1136 finalize_local_symbols(unsigned int index
, off_t off
, Symbol_table
* symtab
)
1137 { return this->do_finalize_local_symbols(index
, off
, symtab
); }
1139 // Set the output dynamic symbol table indexes for the local variables.
1141 set_local_dynsym_indexes(unsigned int index
)
1142 { return this->do_set_local_dynsym_indexes(index
); }
1144 // Set the offset where local dynamic symbol information will be stored.
1146 set_local_dynsym_offset(off_t off
)
1147 { return this->do_set_local_dynsym_offset(off
); }
1149 // Record a dynamic relocation against an input section from this object.
1151 add_dyn_reloc(unsigned int index
)
1153 if (this->dyn_reloc_count_
== 0)
1154 this->first_dyn_reloc_
= index
;
1155 ++this->dyn_reloc_count_
;
1158 // Return the index of the first dynamic relocation.
1160 first_dyn_reloc() const
1161 { return this->first_dyn_reloc_
; }
1163 // Return the count of dynamic relocations.
1165 dyn_reloc_count() const
1166 { return this->dyn_reloc_count_
; }
1168 // Relocate the input sections and write out the local symbols.
1170 relocate(const Symbol_table
* symtab
, const Layout
* layout
, Output_file
* of
)
1171 { return this->do_relocate(symtab
, layout
, of
); }
1173 // Return whether an input section is being included in the link.
1175 is_section_included(unsigned int shndx
) const
1177 gold_assert(shndx
< this->output_sections_
.size());
1178 return this->output_sections_
[shndx
] != NULL
;
1181 // The output section of the input section with index SHNDX.
1182 // This is only used currently to remove a section from the link in
1185 set_output_section(unsigned int shndx
, Output_section
* os
)
1187 gold_assert(shndx
< this->output_sections_
.size());
1188 this->output_sections_
[shndx
] = os
;
1191 // Set the offset of an input section within its output section.
1193 set_section_offset(unsigned int shndx
, uint64_t off
)
1194 { this->do_set_section_offset(shndx
, off
); }
1196 // Return true if we need to wait for output sections to be written
1197 // before we can apply relocations. This is true if the object has
1198 // any relocations for sections which require special handling, such
1199 // as the exception frame section.
1201 relocs_must_follow_section_writes() const
1202 { return this->relocs_must_follow_section_writes_
; }
1204 // Return the object merge map.
1207 { return this->object_merge_map_
; }
1209 // Set the object merge map.
1211 set_merge_map(Object_merge_map
* object_merge_map
)
1213 gold_assert(this->object_merge_map_
== NULL
);
1214 this->object_merge_map_
= object_merge_map
;
1217 // Record the relocatable reloc info for an input reloc section.
1219 set_relocatable_relocs(unsigned int reloc_shndx
, Relocatable_relocs
* rr
)
1221 gold_assert(reloc_shndx
< this->shnum());
1222 (*this->map_to_relocatable_relocs_
)[reloc_shndx
] = rr
;
1225 // Get the relocatable reloc info for an input reloc section.
1227 relocatable_relocs(unsigned int reloc_shndx
)
1229 gold_assert(reloc_shndx
< this->shnum());
1230 return (*this->map_to_relocatable_relocs_
)[reloc_shndx
];
1233 // Layout sections whose layout was deferred while waiting for
1234 // input files from a plugin.
1236 layout_deferred_sections(Layout
* layout
)
1237 { this->do_layout_deferred_sections(layout
); }
1239 // Return the index of the first incremental relocation for symbol SYMNDX.
1240 virtual unsigned int
1241 do_get_incremental_reloc_base(unsigned int symndx
) const
1242 { return this->reloc_bases_
[symndx
]; }
1244 // Return the number of incremental relocations for symbol SYMNDX.
1245 virtual unsigned int
1246 do_get_incremental_reloc_count(unsigned int symndx
) const
1247 { return this->reloc_counts_
[symndx
]; }
1249 // Return the word size of the object file.
1252 { return this->do_elfsize(); }
1254 // Return TRUE if this is a big-endian object file.
1256 is_big_endian() const
1257 { return this->do_is_big_endian(); }
1260 // The output section to be used for each input section, indexed by
1261 // the input section number. The output section is NULL if the
1262 // input section is to be discarded.
1263 typedef std::vector
<Output_section
*> Output_sections
;
1265 // Read the relocs--implemented by child class.
1267 do_read_relocs(Read_relocs_data
*) = 0;
1269 // Process the relocs--implemented by child class.
1271 do_gc_process_relocs(Symbol_table
*, Layout
*, Read_relocs_data
*) = 0;
1273 // Scan the relocs--implemented by child class.
1275 do_scan_relocs(Symbol_table
*, Layout
*, Read_relocs_data
*) = 0;
1277 // Return the value of a local symbol.
1279 do_local_symbol_value(unsigned int symndx
, uint64_t addend
) const = 0;
1281 // Return the PLT offset of a local symbol.
1282 virtual unsigned int
1283 do_local_plt_offset(unsigned int symndx
) const = 0;
1285 // Return whether a local symbol has a GOT offset of a given type.
1287 do_local_has_got_offset(unsigned int symndx
,
1288 unsigned int got_type
) const = 0;
1290 // Return the GOT offset of a given type of a local symbol.
1291 virtual unsigned int
1292 do_local_got_offset(unsigned int symndx
, unsigned int got_type
) const = 0;
1294 // Set the GOT offset with a given type for a local symbol.
1296 do_set_local_got_offset(unsigned int symndx
, unsigned int got_type
,
1297 unsigned int got_offset
) = 0;
1299 // Return whether local symbol SYMNDX is a TLS symbol.
1301 do_local_is_tls(unsigned int symndx
) const = 0;
1303 // Return the number of local symbols--implemented by child class.
1304 virtual unsigned int
1305 do_local_symbol_count() const = 0;
1307 // Return the number of output local symbols--implemented by child class.
1308 virtual unsigned int
1309 do_output_local_symbol_count() const = 0;
1311 // Return the file offset for local symbols--implemented by child class.
1313 do_local_symbol_offset() const = 0;
1315 // Count local symbols--implemented by child class.
1317 do_count_local_symbols(Stringpool_template
<char>*,
1318 Stringpool_template
<char>*) = 0;
1320 // Finalize the local symbols. Set the output symbol table indexes
1321 // for the local variables, and set the offset where local symbol
1322 // information will be stored.
1323 virtual unsigned int
1324 do_finalize_local_symbols(unsigned int, off_t
, Symbol_table
*) = 0;
1326 // Set the output dynamic symbol table indexes for the local variables.
1327 virtual unsigned int
1328 do_set_local_dynsym_indexes(unsigned int) = 0;
1330 // Set the offset where local dynamic symbol information will be stored.
1331 virtual unsigned int
1332 do_set_local_dynsym_offset(off_t
) = 0;
1334 // Relocate the input sections and write out the local
1335 // symbols--implemented by child class.
1337 do_relocate(const Symbol_table
* symtab
, const Layout
*, Output_file
* of
) = 0;
1339 // Set the offset of a section--implemented by child class.
1341 do_set_section_offset(unsigned int shndx
, uint64_t off
) = 0;
1343 // Layout sections whose layout was deferred while waiting for
1344 // input files from a plugin--implemented by child class.
1346 do_layout_deferred_sections(Layout
*) = 0;
1348 // Given a section index, return the corresponding Output_section.
1349 // The return value will be NULL if the section is not included in
1352 do_output_section(unsigned int shndx
) const
1354 gold_assert(shndx
< this->output_sections_
.size());
1355 return this->output_sections_
[shndx
];
1358 // Return the vector mapping input sections to output sections.
1361 { return this->output_sections_
; }
1363 const Output_sections
&
1364 output_sections() const
1365 { return this->output_sections_
; }
1367 // Set the size of the relocatable relocs array.
1369 size_relocatable_relocs()
1371 this->map_to_relocatable_relocs_
=
1372 new std::vector
<Relocatable_relocs
*>(this->shnum());
1375 // Record that we must wait for the output sections to be written
1376 // before applying relocations.
1378 set_relocs_must_follow_section_writes()
1379 { this->relocs_must_follow_section_writes_
= true; }
1381 // Allocate the array for counting incremental relocations.
1383 allocate_incremental_reloc_counts()
1385 unsigned int nsyms
= this->do_get_global_symbols()->size();
1386 this->reloc_counts_
= new unsigned int[nsyms
];
1387 gold_assert(this->reloc_counts_
!= NULL
);
1388 memset(this->reloc_counts_
, 0, nsyms
* sizeof(unsigned int));
1391 // Record a relocation in this object referencing global symbol SYMNDX.
1392 // Used for tracking incremental link information.
1394 count_incremental_reloc(unsigned int symndx
)
1396 unsigned int nsyms
= this->do_get_global_symbols()->size();
1397 gold_assert(symndx
< nsyms
);
1398 gold_assert(this->reloc_counts_
!= NULL
);
1399 ++this->reloc_counts_
[symndx
];
1402 // Finalize the incremental relocation information.
1404 finalize_incremental_relocs(Layout
* layout
, bool clear_counts
);
1406 // Return the index of the next relocation to be written for global symbol
1407 // SYMNDX. Only valid after finalize_incremental_relocs() has been called.
1409 next_incremental_reloc_index(unsigned int symndx
)
1411 unsigned int nsyms
= this->do_get_global_symbols()->size();
1413 gold_assert(this->reloc_counts_
!= NULL
);
1414 gold_assert(this->reloc_bases_
!= NULL
);
1415 gold_assert(symndx
< nsyms
);
1417 unsigned int counter
= this->reloc_counts_
[symndx
]++;
1418 return this->reloc_bases_
[symndx
] + counter
;
1421 // Return the word size of the object file--
1422 // implemented by child class.
1424 do_elfsize() const = 0;
1426 // Return TRUE if this is a big-endian object file--
1427 // implemented by child class.
1429 do_is_big_endian() const = 0;
1432 // Mapping from input sections to output section.
1433 Output_sections output_sections_
;
1434 // Mapping from input section index to the information recorded for
1435 // the relocations. This is only used for a relocatable link.
1436 std::vector
<Relocatable_relocs
*>* map_to_relocatable_relocs_
;
1437 // Mappings for merge sections. This is managed by the code in the
1439 Object_merge_map
* object_merge_map_
;
1440 // Whether we need to wait for output sections to be written before
1441 // we can apply relocations.
1442 bool relocs_must_follow_section_writes_
;
1443 // Used to store the relocs data computed by the Read_relocs pass.
1444 // Used during garbage collection of unused sections.
1445 Read_relocs_data
* rd_
;
1446 // Used to store the symbols data computed by the Read_symbols pass.
1447 // Again used during garbage collection when laying out referenced
1449 gold::Symbols_data
* sd_
;
1450 // Per-symbol counts of relocations, for incremental links.
1451 unsigned int* reloc_counts_
;
1452 // Per-symbol base indexes of relocations, for incremental links.
1453 unsigned int* reloc_bases_
;
1454 // Index of the first dynamic relocation for this object.
1455 unsigned int first_dyn_reloc_
;
1456 // Count of dynamic relocations for this object.
1457 unsigned int dyn_reloc_count_
;
1460 // This class is used to handle relocations against a section symbol
1461 // in an SHF_MERGE section. For such a symbol, we need to know the
1462 // addend of the relocation before we can determine the final value.
1463 // The addend gives us the location in the input section, and we can
1464 // determine how it is mapped to the output section. For a
1465 // non-section symbol, we apply the addend to the final value of the
1466 // symbol; that is done in finalize_local_symbols, and does not use
1470 class Merged_symbol_value
1473 typedef typename
elfcpp::Elf_types
<size
>::Elf_Addr Value
;
1475 // We use a hash table to map offsets in the input section to output
1477 typedef Unordered_map
<section_offset_type
, Value
> Output_addresses
;
1479 Merged_symbol_value(Value input_value
, Value output_start_address
)
1480 : input_value_(input_value
), output_start_address_(output_start_address
),
1484 // Initialize the hash table.
1486 initialize_input_to_output_map(const Relobj
*, unsigned int input_shndx
);
1488 // Release the hash table to save space.
1490 free_input_to_output_map()
1491 { this->output_addresses_
.clear(); }
1493 // Get the output value corresponding to an addend. The object and
1494 // input section index are passed in because the caller will have
1495 // them; otherwise we could store them here.
1497 value(const Relobj
* object
, unsigned int input_shndx
, Value addend
) const
1499 // This is a relocation against a section symbol. ADDEND is the
1500 // offset in the section. The result should be the start of some
1501 // merge area. If the object file wants something else, it should
1502 // use a regular symbol rather than a section symbol.
1503 // Unfortunately, PR 6658 shows a case in which the object file
1504 // refers to the section symbol, but uses a negative ADDEND to
1505 // compensate for a PC relative reloc. We can't handle the
1506 // general case. However, we can handle the special case of a
1507 // negative addend, by assuming that it refers to the start of the
1508 // section. Of course, that means that we have to guess when
1509 // ADDEND is negative. It is normal to see a 32-bit value here
1510 // even when the template parameter size is 64, as 64-bit object
1511 // file formats have 32-bit relocations. We know this is a merge
1512 // section, so we know it has to fit into memory. So we assume
1513 // that we won't see a value larger than a large 32-bit unsigned
1514 // value. This will break objects with very very large merge
1515 // sections; they probably break in other ways anyhow.
1516 Value input_offset
= this->input_value_
;
1517 if (addend
< 0xffffff00)
1519 input_offset
+= addend
;
1522 typename
Output_addresses::const_iterator p
=
1523 this->output_addresses_
.find(input_offset
);
1524 if (p
!= this->output_addresses_
.end())
1525 return p
->second
+ addend
;
1527 return (this->value_from_output_section(object
, input_shndx
, input_offset
)
1532 // Get the output value for an input offset if we couldn't find it
1533 // in the hash table.
1535 value_from_output_section(const Relobj
*, unsigned int input_shndx
,
1536 Value input_offset
) const;
1538 // The value of the section symbol in the input file. This is
1539 // normally zero, but could in principle be something else.
1541 // The start address of this merged section in the output file.
1542 Value output_start_address_
;
1543 // A hash table which maps offsets in the input section to output
1544 // addresses. This only maps specific offsets, not all offsets.
1545 Output_addresses output_addresses_
;
1548 // This POD class is holds the value of a symbol. This is used for
1549 // local symbols, and for all symbols during relocation processing.
1550 // For special sections, such as SHF_MERGE sections, this calls a
1551 // function to get the final symbol value.
1557 typedef typename
elfcpp::Elf_types
<size
>::Elf_Addr Value
;
1560 : output_symtab_index_(0), output_dynsym_index_(-1U), input_shndx_(0),
1561 is_ordinary_shndx_(false), is_section_symbol_(false),
1562 is_tls_symbol_(false), is_ifunc_symbol_(false), has_output_value_(true)
1563 { this->u_
.value
= 0; }
1567 if (!this->has_output_value_
)
1568 delete this->u_
.merged_symbol_value
;
1571 // Get the value of this symbol. OBJECT is the object in which this
1572 // symbol is defined, and ADDEND is an addend to add to the value.
1573 template<bool big_endian
>
1575 value(const Sized_relobj_file
<size
, big_endian
>* object
, Value addend
) const
1577 if (this->has_output_value_
)
1578 return this->u_
.value
+ addend
;
1581 gold_assert(this->is_ordinary_shndx_
);
1582 return this->u_
.merged_symbol_value
->value(object
, this->input_shndx_
,
1587 // Set the value of this symbol in the output symbol table.
1589 set_output_value(Value value
)
1590 { this->u_
.value
= value
; }
1592 // For a section symbol in a merged section, we need more
1595 set_merged_symbol_value(Merged_symbol_value
<size
>* msv
)
1597 gold_assert(this->is_section_symbol_
);
1598 this->has_output_value_
= false;
1599 this->u_
.merged_symbol_value
= msv
;
1602 // Initialize the input to output map for a section symbol in a
1603 // merged section. We also initialize the value of a non-section
1604 // symbol in a merged section.
1606 initialize_input_to_output_map(const Relobj
* object
)
1608 if (!this->has_output_value_
)
1610 gold_assert(this->is_section_symbol_
&& this->is_ordinary_shndx_
);
1611 Merged_symbol_value
<size
>* msv
= this->u_
.merged_symbol_value
;
1612 msv
->initialize_input_to_output_map(object
, this->input_shndx_
);
1616 // Free the input to output map for a section symbol in a merged
1619 free_input_to_output_map()
1621 if (!this->has_output_value_
)
1622 this->u_
.merged_symbol_value
->free_input_to_output_map();
1625 // Set the value of the symbol from the input file. This is only
1626 // called by count_local_symbols, to communicate the value to
1627 // finalize_local_symbols.
1629 set_input_value(Value value
)
1630 { this->u_
.value
= value
; }
1632 // Return the input value. This is only called by
1633 // finalize_local_symbols and (in special cases) relocate_section.
1636 { return this->u_
.value
; }
1638 // Return whether we have set the index in the output symbol table
1641 is_output_symtab_index_set() const
1643 return (this->output_symtab_index_
!= 0
1644 && this->output_symtab_index_
!= -2U);
1647 // Return whether this symbol may be discarded from the normal
1650 may_be_discarded_from_output_symtab() const
1652 gold_assert(!this->is_output_symtab_index_set());
1653 return this->output_symtab_index_
!= -2U;
1656 // Return whether this symbol has an entry in the output symbol
1659 has_output_symtab_entry() const
1661 gold_assert(this->is_output_symtab_index_set());
1662 return this->output_symtab_index_
!= -1U;
1665 // Return the index in the output symbol table.
1667 output_symtab_index() const
1669 gold_assert(this->is_output_symtab_index_set()
1670 && this->output_symtab_index_
!= -1U);
1671 return this->output_symtab_index_
;
1674 // Set the index in the output symbol table.
1676 set_output_symtab_index(unsigned int i
)
1678 gold_assert(!this->is_output_symtab_index_set());
1679 gold_assert(i
!= 0 && i
!= -1U && i
!= -2U);
1680 this->output_symtab_index_
= i
;
1683 // Record that this symbol should not go into the output symbol
1686 set_no_output_symtab_entry()
1688 gold_assert(this->output_symtab_index_
== 0);
1689 this->output_symtab_index_
= -1U;
1692 // Record that this symbol must go into the output symbol table,
1693 // because it there is a relocation that uses it.
1695 set_must_have_output_symtab_entry()
1697 gold_assert(!this->is_output_symtab_index_set());
1698 this->output_symtab_index_
= -2U;
1701 // Set the index in the output dynamic symbol table.
1703 set_needs_output_dynsym_entry()
1705 gold_assert(!this->is_section_symbol());
1706 this->output_dynsym_index_
= 0;
1709 // Return whether this symbol should go into the dynamic symbol
1712 needs_output_dynsym_entry() const
1714 return this->output_dynsym_index_
!= -1U;
1717 // Return whether this symbol has an entry in the dynamic symbol
1720 has_output_dynsym_entry() const
1722 gold_assert(this->output_dynsym_index_
!= 0);
1723 return this->output_dynsym_index_
!= -1U;
1726 // Record that this symbol should go into the dynamic symbol table.
1728 set_output_dynsym_index(unsigned int i
)
1730 gold_assert(this->output_dynsym_index_
== 0);
1731 gold_assert(i
!= 0 && i
!= -1U);
1732 this->output_dynsym_index_
= i
;
1735 // Return the index in the output dynamic symbol table.
1737 output_dynsym_index() const
1739 gold_assert(this->output_dynsym_index_
!= 0
1740 && this->output_dynsym_index_
!= -1U);
1741 return this->output_dynsym_index_
;
1744 // Set the index of the input section in the input file.
1746 set_input_shndx(unsigned int i
, bool is_ordinary
)
1748 this->input_shndx_
= i
;
1749 // input_shndx_ field is a bitfield, so make sure that the value
1751 gold_assert(this->input_shndx_
== i
);
1752 this->is_ordinary_shndx_
= is_ordinary
;
1755 // Return the index of the input section in the input file.
1757 input_shndx(bool* is_ordinary
) const
1759 *is_ordinary
= this->is_ordinary_shndx_
;
1760 return this->input_shndx_
;
1763 // Whether this is a section symbol.
1765 is_section_symbol() const
1766 { return this->is_section_symbol_
; }
1768 // Record that this is a section symbol.
1770 set_is_section_symbol()
1772 gold_assert(!this->needs_output_dynsym_entry());
1773 this->is_section_symbol_
= true;
1776 // Record that this is a TLS symbol.
1779 { this->is_tls_symbol_
= true; }
1781 // Return true if this is a TLS symbol.
1783 is_tls_symbol() const
1784 { return this->is_tls_symbol_
; }
1786 // Record that this is an IFUNC symbol.
1788 set_is_ifunc_symbol()
1789 { this->is_ifunc_symbol_
= true; }
1791 // Return true if this is an IFUNC symbol.
1793 is_ifunc_symbol() const
1794 { return this->is_ifunc_symbol_
; }
1796 // Return true if this has output value.
1798 has_output_value() const
1799 { return this->has_output_value_
; }
1802 // The index of this local symbol in the output symbol table. This
1803 // will be 0 if no value has been assigned yet, and the symbol may
1804 // be omitted. This will be -1U if the symbol should not go into
1805 // the symbol table. This will be -2U if the symbol must go into
1806 // the symbol table, but no index has been assigned yet.
1807 unsigned int output_symtab_index_
;
1808 // The index of this local symbol in the dynamic symbol table. This
1809 // will be -1U if the symbol should not go into the symbol table.
1810 unsigned int output_dynsym_index_
;
1811 // The section index in the input file in which this symbol is
1813 unsigned int input_shndx_
: 27;
1814 // Whether the section index is an ordinary index, not a special
1816 bool is_ordinary_shndx_
: 1;
1817 // Whether this is a STT_SECTION symbol.
1818 bool is_section_symbol_
: 1;
1819 // Whether this is a STT_TLS symbol.
1820 bool is_tls_symbol_
: 1;
1821 // Whether this is a STT_GNU_IFUNC symbol.
1822 bool is_ifunc_symbol_
: 1;
1823 // Whether this symbol has a value for the output file. This is
1824 // normally set to true during Layout::finalize, by
1825 // finalize_local_symbols. It will be false for a section symbol in
1826 // a merge section, as for such symbols we can not determine the
1827 // value to use in a relocation until we see the addend.
1828 bool has_output_value_
: 1;
1831 // This is used if has_output_value_ is true. Between
1832 // count_local_symbols and finalize_local_symbols, this is the
1833 // value in the input file. After finalize_local_symbols, it is
1834 // the value in the output file.
1836 // This is used if has_output_value_ is false. It points to the
1837 // information we need to get the value for a merge section.
1838 Merged_symbol_value
<size
>* merged_symbol_value
;
1842 // This type is used to modify relocations for -fsplit-stack. It is
1843 // indexed by relocation index, and means that the relocation at that
1844 // index should use the symbol from the vector, rather than the one
1845 // indicated by the relocation.
1847 class Reloc_symbol_changes
1850 Reloc_symbol_changes(size_t count
)
1855 set(size_t i
, Symbol
* sym
)
1856 { this->vec_
[i
] = sym
; }
1859 operator[](size_t i
) const
1860 { return this->vec_
[i
]; }
1863 std::vector
<Symbol
*> vec_
;
1866 // Type for mapping section index to uncompressed size and contents.
1868 struct Compressed_section_info
1870 section_size_type size
;
1871 const unsigned char* contents
;
1873 typedef std::map
<unsigned int, Compressed_section_info
> Compressed_section_map
;
1875 // Abstract base class for a regular object file, either a real object file
1876 // or an incremental (unchanged) object. This is size and endian specific.
1878 template<int size
, bool big_endian
>
1879 class Sized_relobj
: public Relobj
1882 typedef typename
elfcpp::Elf_types
<size
>::Elf_Addr Address
;
1883 typedef Relobj::Symbols Symbols
;
1885 static const Address invalid_address
= static_cast<Address
>(0) - 1;
1887 Sized_relobj(const std::string
& name
, Input_file
* input_file
)
1888 : Relobj(name
, input_file
), local_got_offsets_(), section_offsets_()
1891 Sized_relobj(const std::string
& name
, Input_file
* input_file
,
1893 : Relobj(name
, input_file
, offset
), local_got_offsets_(), section_offsets_()
1899 // If this is a regular object, return a pointer to the Sized_relobj_file
1900 // object. Otherwise, return NULL.
1901 virtual Sized_relobj_file
<size
, big_endian
>*
1905 const virtual Sized_relobj_file
<size
, big_endian
>*
1906 sized_relobj() const
1909 // Checks if the offset of input section SHNDX within its output
1910 // section is invalid.
1912 is_output_section_offset_invalid(unsigned int shndx
) const
1913 { return this->get_output_section_offset(shndx
) == invalid_address
; }
1915 // Get the offset of input section SHNDX within its output section.
1916 // This is -1 if the input section requires a special mapping, such
1917 // as a merge section. The output section can be found in the
1918 // output_sections_ field of the parent class Relobj.
1920 get_output_section_offset(unsigned int shndx
) const
1922 gold_assert(shndx
< this->section_offsets_
.size());
1923 return this->section_offsets_
[shndx
];
1926 // Iterate over local symbols, calling a visitor class V for each GOT offset
1927 // associated with a local symbol.
1929 do_for_all_local_got_entries(Got_offset_list::Visitor
* v
) const;
1932 typedef Relobj::Output_sections Output_sections
;
1934 // Clear the local symbol information.
1937 { this->local_got_offsets_
.clear(); }
1939 // Return the vector of section offsets.
1940 std::vector
<Address
>&
1942 { return this->section_offsets_
; }
1944 // Get the address of an output section.
1946 do_output_section_address(unsigned int shndx
);
1948 // Get the offset of a section.
1950 do_output_section_offset(unsigned int shndx
) const
1952 Address off
= this->get_output_section_offset(shndx
);
1953 if (off
== invalid_address
)
1958 // Set the offset of a section.
1960 do_set_section_offset(unsigned int shndx
, uint64_t off
)
1962 gold_assert(shndx
< this->section_offsets_
.size());
1963 this->section_offsets_
[shndx
] =
1964 (off
== static_cast<uint64_t>(-1)
1966 : convert_types
<Address
, uint64_t>(off
));
1969 // Return whether the local symbol SYMNDX has a GOT offset of type
1972 do_local_has_got_offset(unsigned int symndx
, unsigned int got_type
) const
1974 Local_got_offsets::const_iterator p
=
1975 this->local_got_offsets_
.find(symndx
);
1976 return (p
!= this->local_got_offsets_
.end()
1977 && p
->second
->get_offset(got_type
) != -1U);
1980 // Return the GOT offset of type GOT_TYPE of the local symbol
1983 do_local_got_offset(unsigned int symndx
, unsigned int got_type
) const
1985 Local_got_offsets::const_iterator p
=
1986 this->local_got_offsets_
.find(symndx
);
1987 gold_assert(p
!= this->local_got_offsets_
.end());
1988 unsigned int off
= p
->second
->get_offset(got_type
);
1989 gold_assert(off
!= -1U);
1993 // Set the GOT offset with type GOT_TYPE of the local symbol SYMNDX
1996 do_set_local_got_offset(unsigned int symndx
, unsigned int got_type
,
1997 unsigned int got_offset
)
1999 Local_got_offsets::const_iterator p
=
2000 this->local_got_offsets_
.find(symndx
);
2001 if (p
!= this->local_got_offsets_
.end())
2002 p
->second
->set_offset(got_type
, got_offset
);
2005 Got_offset_list
* g
= new Got_offset_list(got_type
, got_offset
);
2006 std::pair
<Local_got_offsets::iterator
, bool> ins
=
2007 this->local_got_offsets_
.insert(std::make_pair(symndx
, g
));
2008 gold_assert(ins
.second
);
2012 // Return the word size of the object file.
2017 // Return TRUE if this is a big-endian object file.
2019 do_is_big_endian() const
2020 { return big_endian
; }
2023 // The GOT offsets of local symbols. This map also stores GOT offsets
2024 // for tp-relative offsets for TLS symbols.
2025 typedef Unordered_map
<unsigned int, Got_offset_list
*> Local_got_offsets
;
2027 // GOT offsets for local non-TLS symbols, and tp-relative offsets
2028 // for TLS symbols, indexed by symbol number.
2029 Local_got_offsets local_got_offsets_
;
2030 // For each input section, the offset of the input section in its
2031 // output section. This is INVALID_ADDRESS if the input section requires a
2033 std::vector
<Address
> section_offsets_
;
2036 // A regular object file. This is size and endian specific.
2038 template<int size
, bool big_endian
>
2039 class Sized_relobj_file
: public Sized_relobj
<size
, big_endian
>
2042 typedef typename
elfcpp::Elf_types
<size
>::Elf_Addr Address
;
2043 typedef typename Sized_relobj
<size
, big_endian
>::Symbols Symbols
;
2044 typedef std::vector
<Symbol_value
<size
> > Local_values
;
2046 static const Address invalid_address
= static_cast<Address
>(0) - 1;
2048 enum Compute_final_local_value_status
2052 // An error occurred.
2054 // The local symbol has no output section.
2058 Sized_relobj_file(const std::string
& name
,
2059 Input_file
* input_file
,
2061 const typename
elfcpp::Ehdr
<size
, big_endian
>&);
2063 ~Sized_relobj_file();
2065 // Set up the object file based on TARGET.
2068 { this->do_setup(); }
2070 // Return a pointer to the Sized_relobj_file object.
2071 Sized_relobj_file
<size
, big_endian
>*
2075 const Sized_relobj_file
<size
, big_endian
>*
2076 sized_relobj() const
2079 // Return the ELF file type.
2082 { return this->e_type_
; }
2084 // Return the number of symbols. This is only valid after
2085 // Object::add_symbols has been called.
2087 symbol_count() const
2088 { return this->local_symbol_count_
+ this->symbols_
.size(); }
2090 // If SYM is the index of a global symbol in the object file's
2091 // symbol table, return the Symbol object. Otherwise, return NULL.
2093 global_symbol(unsigned int sym
) const
2095 if (sym
>= this->local_symbol_count_
)
2097 gold_assert(sym
- this->local_symbol_count_
< this->symbols_
.size());
2098 return this->symbols_
[sym
- this->local_symbol_count_
];
2103 // Return the section index of symbol SYM. Set *VALUE to its value
2104 // in the object file. Set *IS_ORDINARY if this is an ordinary
2105 // section index, not a special code between SHN_LORESERVE and
2106 // SHN_HIRESERVE. Note that for a symbol which is not defined in
2107 // this object file, this will set *VALUE to 0 and return SHN_UNDEF;
2108 // it will not return the final value of the symbol in the link.
2110 symbol_section_and_value(unsigned int sym
, Address
* value
, bool* is_ordinary
);
2112 // Return a pointer to the Symbol_value structure which holds the
2113 // value of a local symbol.
2114 const Symbol_value
<size
>*
2115 local_symbol(unsigned int sym
) const
2117 gold_assert(sym
< this->local_values_
.size());
2118 return &this->local_values_
[sym
];
2121 // Return the index of local symbol SYM in the ordinary symbol
2122 // table. A value of -1U means that the symbol is not being output.
2124 symtab_index(unsigned int sym
) const
2126 gold_assert(sym
< this->local_values_
.size());
2127 return this->local_values_
[sym
].output_symtab_index();
2130 // Return the index of local symbol SYM in the dynamic symbol
2131 // table. A value of -1U means that the symbol is not being output.
2133 dynsym_index(unsigned int sym
) const
2135 gold_assert(sym
< this->local_values_
.size());
2136 return this->local_values_
[sym
].output_dynsym_index();
2139 // Return the input section index of local symbol SYM.
2141 local_symbol_input_shndx(unsigned int sym
, bool* is_ordinary
) const
2143 gold_assert(sym
< this->local_values_
.size());
2144 return this->local_values_
[sym
].input_shndx(is_ordinary
);
2147 // Record that local symbol SYM must be in the output symbol table.
2149 set_must_have_output_symtab_entry(unsigned int sym
)
2151 gold_assert(sym
< this->local_values_
.size());
2152 this->local_values_
[sym
].set_must_have_output_symtab_entry();
2155 // Record that local symbol SYM needs a dynamic symbol entry.
2157 set_needs_output_dynsym_entry(unsigned int sym
)
2159 gold_assert(sym
< this->local_values_
.size());
2160 this->local_values_
[sym
].set_needs_output_dynsym_entry();
2163 // Return whether the local symbol SYMNDX has a PLT offset.
2165 local_has_plt_offset(unsigned int symndx
) const;
2167 // Set the PLT offset of the local symbol SYMNDX.
2169 set_local_plt_offset(unsigned int symndx
, unsigned int plt_offset
);
2171 // Adjust this local symbol value. Return false if the symbol
2172 // should be discarded from the output file.
2174 adjust_local_symbol(Symbol_value
<size
>* lv
) const
2175 { return this->do_adjust_local_symbol(lv
); }
2177 // Return the name of the symbol that spans the given offset in the
2178 // specified section in this object. This is used only for error
2179 // messages and is not particularly efficient.
2181 get_symbol_location_info(unsigned int shndx
, off_t offset
,
2182 Symbol_location_info
* info
);
2184 // Look for a kept section corresponding to the given discarded section,
2185 // and return its output address. This is used only for relocations in
2186 // debugging sections.
2188 map_to_kept_section(unsigned int shndx
, bool* found
) const;
2190 // Compute final local symbol value. R_SYM is the local symbol index.
2191 // LV_IN points to a local symbol value containing the input value.
2192 // LV_OUT points to a local symbol value storing the final output value,
2193 // which must not be a merged symbol value since before calling this
2194 // method to avoid memory leak. SYMTAB points to a symbol table.
2196 // The method returns a status code at return. If the return status is
2197 // CFLV_OK, *LV_OUT contains the final value. If the return status is
2198 // CFLV_ERROR, *LV_OUT is 0. If the return status is CFLV_DISCARDED,
2199 // *LV_OUT is not modified.
2200 Compute_final_local_value_status
2201 compute_final_local_value(unsigned int r_sym
,
2202 const Symbol_value
<size
>* lv_in
,
2203 Symbol_value
<size
>* lv_out
,
2204 const Symbol_table
* symtab
);
2207 typedef typename Sized_relobj
<size
, big_endian
>::Output_sections
2214 // Read the symbols.
2216 do_read_symbols(Read_symbols_data
*);
2218 // Return the value of a local symbol.
2220 do_local_symbol_value(unsigned int symndx
, uint64_t addend
) const
2222 const Symbol_value
<size
>* symval
= this->local_symbol(symndx
);
2223 return symval
->value(this, addend
);
2226 // Return the PLT offset for a local symbol. It is an error to call
2227 // this if it doesn't have one.
2229 do_local_plt_offset(unsigned int symndx
) const;
2231 // Return whether local symbol SYMNDX is a TLS symbol.
2233 do_local_is_tls(unsigned int symndx
) const
2234 { return this->local_symbol(symndx
)->is_tls_symbol(); }
2236 // Return the number of local symbols.
2238 do_local_symbol_count() const
2239 { return this->local_symbol_count_
; }
2241 // Return the number of local symbols in the output symbol table.
2243 do_output_local_symbol_count() const
2244 { return this->output_local_symbol_count_
; }
2246 // Return the number of local symbols in the output symbol table.
2248 do_local_symbol_offset() const
2249 { return this->local_symbol_offset_
; }
2251 // Lay out the input sections.
2253 do_layout(Symbol_table
*, Layout
*, Read_symbols_data
*);
2255 // Layout sections whose layout was deferred while waiting for
2256 // input files from a plugin.
2258 do_layout_deferred_sections(Layout
*);
2260 // Add the symbols to the symbol table.
2262 do_add_symbols(Symbol_table
*, Read_symbols_data
*, Layout
*);
2264 Archive::Should_include
2265 do_should_include_member(Symbol_table
* symtab
, Layout
*, Read_symbols_data
*,
2268 // Iterate over global symbols, calling a visitor class V for each.
2270 do_for_all_global_symbols(Read_symbols_data
* sd
,
2271 Library_base::Symbol_visitor_base
* v
);
2275 do_read_relocs(Read_relocs_data
*);
2277 // Process the relocs to find list of referenced sections. Used only
2278 // during garbage collection.
2280 do_gc_process_relocs(Symbol_table
*, Layout
*, Read_relocs_data
*);
2282 // Scan the relocs and adjust the symbol table.
2284 do_scan_relocs(Symbol_table
*, Layout
*, Read_relocs_data
*);
2286 // Count the local symbols.
2288 do_count_local_symbols(Stringpool_template
<char>*,
2289 Stringpool_template
<char>*);
2291 // Finalize the local symbols.
2293 do_finalize_local_symbols(unsigned int, off_t
, Symbol_table
*);
2295 // Set the offset where local dynamic symbol information will be stored.
2297 do_set_local_dynsym_indexes(unsigned int);
2299 // Set the offset where local dynamic symbol information will be stored.
2301 do_set_local_dynsym_offset(off_t
);
2303 // Relocate the input sections and write out the local symbols.
2305 do_relocate(const Symbol_table
* symtab
, const Layout
*, Output_file
* of
);
2307 // Get the size of a section.
2309 do_section_size(unsigned int shndx
)
2310 { return this->elf_file_
.section_size(shndx
); }
2312 // Get the name of a section.
2314 do_section_name(unsigned int shndx
)
2315 { return this->elf_file_
.section_name(shndx
); }
2317 // Return the location of the contents of a section.
2318 const unsigned char*
2319 do_section_contents(unsigned int shndx
, section_size_type
* plen
,
2322 Object::Location
loc(this->elf_file_
.section_contents(shndx
));
2323 *plen
= convert_to_section_size_type(loc
.data_size
);
2326 static const unsigned char empty
[1] = { '\0' };
2329 return this->get_view(loc
.file_offset
, *plen
, true, cache
);
2332 // Return section flags.
2334 do_section_flags(unsigned int shndx
);
2336 // Return section entsize.
2338 do_section_entsize(unsigned int shndx
);
2340 // Return section address.
2342 do_section_address(unsigned int shndx
)
2343 { return this->elf_file_
.section_addr(shndx
); }
2345 // Return section type.
2347 do_section_type(unsigned int shndx
)
2348 { return this->elf_file_
.section_type(shndx
); }
2350 // Return the section link field.
2352 do_section_link(unsigned int shndx
)
2353 { return this->elf_file_
.section_link(shndx
); }
2355 // Return the section info field.
2357 do_section_info(unsigned int shndx
)
2358 { return this->elf_file_
.section_info(shndx
); }
2360 // Return the section alignment.
2362 do_section_addralign(unsigned int shndx
)
2363 { return this->elf_file_
.section_addralign(shndx
); }
2365 // Return the Xindex structure to use.
2367 do_initialize_xindex();
2369 // Get symbol counts.
2371 do_get_global_symbol_counts(const Symbol_table
*, size_t*, size_t*) const;
2373 // Get the global symbols.
2375 do_get_global_symbols() const
2376 { return &this->symbols_
; }
2378 // Adjust a section index if necessary.
2380 adjust_shndx(unsigned int shndx
)
2382 if (shndx
>= elfcpp::SHN_LORESERVE
)
2383 shndx
+= this->elf_file_
.large_shndx_offset();
2387 // Initialize input to output maps for section symbols in merged
2390 initialize_input_to_output_maps();
2392 // Free the input to output maps for section symbols in merged
2395 free_input_to_output_maps();
2397 // Return symbol table section index.
2399 symtab_shndx() const
2400 { return this->symtab_shndx_
; }
2402 // Allow a child class to access the ELF file.
2403 elfcpp::Elf_file
<size
, big_endian
, Object
>*
2405 { return &this->elf_file_
; }
2407 // Allow a child class to access the local values.
2410 { return &this->local_values_
; }
2412 // Views and sizes when relocating.
2415 unsigned char* view
;
2416 typename
elfcpp::Elf_types
<size
>::Elf_Addr address
;
2418 section_size_type view_size
;
2419 bool is_input_output_view
;
2420 bool is_postprocessing_view
;
2421 bool is_ctors_reverse_view
;
2424 typedef std::vector
<View_size
> Views
;
2426 // Stash away info for a number of special sections.
2427 // Return true if any of the sections found require local symbols to be read.
2429 do_find_special_sections(Read_symbols_data
* sd
);
2431 // This may be overriden by a child class.
2433 do_relocate_sections(const Symbol_table
* symtab
, const Layout
* layout
,
2434 const unsigned char* pshdrs
, Output_file
* of
,
2437 // Adjust this local symbol value. Return false if the symbol
2438 // should be discarded from the output file.
2440 do_adjust_local_symbol(Symbol_value
<size
>*) const
2443 // Allow a child to set output local symbol count.
2445 set_output_local_symbol_count(unsigned int value
)
2446 { this->output_local_symbol_count_
= value
; }
2448 // Return TRUE if the section is a compressed debug section, and set
2449 // *UNCOMPRESSED_SIZE to the size of the uncompressed data.
2451 do_section_is_compressed(unsigned int shndx
,
2452 section_size_type
* uncompressed_size
) const
2454 if (this->compressed_sections_
== NULL
)
2456 Compressed_section_map::const_iterator p
=
2457 this->compressed_sections_
->find(shndx
);
2458 if (p
!= this->compressed_sections_
->end())
2460 if (uncompressed_size
!= NULL
)
2461 *uncompressed_size
= p
->second
.size
;
2467 // Return a view of the uncompressed contents of a section. Set *PLEN
2468 // to the size. Set *IS_NEW to true if the contents need to be deleted
2470 const unsigned char*
2471 do_decompressed_section_contents(unsigned int shndx
,
2472 section_size_type
* plen
,
2475 // Discard any buffers of decompressed sections. This is done
2476 // at the end of the Add_symbols task.
2478 do_discard_decompressed_sections();
2482 typedef Sized_relobj_file
<size
, big_endian
> This
;
2483 static const int ehdr_size
= elfcpp::Elf_sizes
<size
>::ehdr_size
;
2484 static const int shdr_size
= elfcpp::Elf_sizes
<size
>::shdr_size
;
2485 static const int sym_size
= elfcpp::Elf_sizes
<size
>::sym_size
;
2486 typedef elfcpp::Shdr
<size
, big_endian
> Shdr
;
2488 // To keep track of discarded comdat sections, we need to map a member
2489 // section index to the object and section index of the corresponding
2491 struct Kept_comdat_section
2493 Kept_comdat_section(Relobj
* a_object
, unsigned int a_shndx
)
2494 : object(a_object
), shndx(a_shndx
)
2499 typedef std::map
<unsigned int, Kept_comdat_section
>
2500 Kept_comdat_section_table
;
2502 // Find the SHT_SYMTAB section, given the section headers.
2504 find_symtab(const unsigned char* pshdrs
);
2506 // Return whether SHDR has the right flags for a GNU style exception
2509 check_eh_frame_flags(const elfcpp::Shdr
<size
, big_endian
>* shdr
) const;
2511 // Return whether there is a section named .eh_frame which might be
2512 // a GNU style exception frame section.
2514 find_eh_frame(const unsigned char* pshdrs
, const char* names
,
2515 section_size_type names_size
) const;
2517 // Whether to include a section group in the link.
2519 include_section_group(Symbol_table
*, Layout
*, unsigned int, const char*,
2520 const unsigned char*, const char*, section_size_type
,
2521 std::vector
<bool>*);
2523 // Whether to include a linkonce section in the link.
2525 include_linkonce_section(Layout
*, unsigned int, const char*,
2526 const elfcpp::Shdr
<size
, big_endian
>&);
2528 // Layout an input section.
2530 layout_section(Layout
* layout
, unsigned int shndx
, const char* name
,
2531 const typename
This::Shdr
& shdr
, unsigned int reloc_shndx
,
2532 unsigned int reloc_type
);
2534 // Layout an input .eh_frame section.
2536 layout_eh_frame_section(Layout
* layout
, const unsigned char* symbols_data
,
2537 section_size_type symbols_size
,
2538 const unsigned char* symbol_names_data
,
2539 section_size_type symbol_names_size
,
2540 unsigned int shndx
, const typename
This::Shdr
&,
2541 unsigned int reloc_shndx
, unsigned int reloc_type
);
2543 // Write section data to the output file. Record the views and
2544 // sizes in VIEWS for use when relocating.
2546 write_sections(const Layout
*, const unsigned char* pshdrs
, Output_file
*,
2549 // Relocate the sections in the output file.
2551 relocate_sections(const Symbol_table
* symtab
, const Layout
* layout
,
2552 const unsigned char* pshdrs
, Output_file
* of
,
2554 { this->do_relocate_sections(symtab
, layout
, pshdrs
, of
, pviews
); }
2556 // Reverse the words in a section. Used for .ctors sections mapped
2557 // to .init_array sections.
2559 reverse_words(unsigned char*, section_size_type
);
2561 // Scan the input relocations for --emit-relocs.
2563 emit_relocs_scan(Symbol_table
*, Layout
*, const unsigned char* plocal_syms
,
2564 const Read_relocs_data::Relocs_list::iterator
&);
2566 // Scan the input relocations for --emit-relocs, templatized on the
2567 // type of the relocation section.
2568 template<int sh_type
>
2570 emit_relocs_scan_reltype(Symbol_table
*, Layout
*,
2571 const unsigned char* plocal_syms
,
2572 const Read_relocs_data::Relocs_list::iterator
&,
2573 Relocatable_relocs
*);
2575 // Scan the input relocations for --incremental.
2577 incremental_relocs_scan(const Read_relocs_data::Relocs_list::iterator
&);
2579 // Scan the input relocations for --incremental, templatized on the
2580 // type of the relocation section.
2581 template<int sh_type
>
2583 incremental_relocs_scan_reltype(
2584 const Read_relocs_data::Relocs_list::iterator
&);
2587 incremental_relocs_write(const Relocate_info
<size
, big_endian
>*,
2588 unsigned int sh_type
,
2589 const unsigned char* prelocs
,
2592 Address output_offset
,
2595 template<int sh_type
>
2597 incremental_relocs_write_reltype(const Relocate_info
<size
, big_endian
>*,
2598 const unsigned char* prelocs
,
2601 Address output_offset
,
2604 // A type shared by split_stack_adjust_reltype and find_functions.
2605 typedef std::map
<section_offset_type
, section_size_type
> Function_offsets
;
2607 // Check for -fsplit-stack routines calling non-split-stack routines.
2609 split_stack_adjust(const Symbol_table
*, const unsigned char* pshdrs
,
2610 unsigned int sh_type
, unsigned int shndx
,
2611 const unsigned char* prelocs
, size_t reloc_count
,
2612 unsigned char* view
, section_size_type view_size
,
2613 Reloc_symbol_changes
** reloc_map
);
2615 template<int sh_type
>
2617 split_stack_adjust_reltype(const Symbol_table
*, const unsigned char* pshdrs
,
2618 unsigned int shndx
, const unsigned char* prelocs
,
2619 size_t reloc_count
, unsigned char* view
,
2620 section_size_type view_size
,
2621 Reloc_symbol_changes
** reloc_map
);
2623 // Find all functions in a section.
2625 find_functions(const unsigned char* pshdrs
, unsigned int shndx
,
2628 // Write out the local symbols.
2630 write_local_symbols(Output_file
*,
2631 const Stringpool_template
<char>*,
2632 const Stringpool_template
<char>*,
2633 Output_symtab_xindex
*,
2634 Output_symtab_xindex
*,
2637 // Record a mapping from discarded section SHNDX to the corresponding
2640 set_kept_comdat_section(unsigned int shndx
, Relobj
* kept_object
,
2641 unsigned int kept_shndx
)
2643 Kept_comdat_section
kept(kept_object
, kept_shndx
);
2644 this->kept_comdat_sections_
.insert(std::make_pair(shndx
, kept
));
2647 // Find the kept section corresponding to the discarded section
2648 // SHNDX. Return true if found.
2650 get_kept_comdat_section(unsigned int shndx
, Relobj
** kept_object
,
2651 unsigned int* kept_shndx
) const
2653 typename
Kept_comdat_section_table::const_iterator p
=
2654 this->kept_comdat_sections_
.find(shndx
);
2655 if (p
== this->kept_comdat_sections_
.end())
2657 *kept_object
= p
->second
.object
;
2658 *kept_shndx
= p
->second
.shndx
;
2662 // Compute final local symbol value. R_SYM is the local symbol index.
2663 // LV_IN points to a local symbol value containing the input value.
2664 // LV_OUT points to a local symbol value storing the final output value,
2665 // which must not be a merged symbol value since before calling this
2666 // method to avoid memory leak. RELOCATABLE indicates whether we are
2667 // linking a relocatable output. OUT_SECTIONS is an array of output
2668 // sections. OUT_OFFSETS is an array of offsets of the sections. SYMTAB
2669 // points to a symbol table.
2671 // The method returns a status code at return. If the return status is
2672 // CFLV_OK, *LV_OUT contains the final value. If the return status is
2673 // CFLV_ERROR, *LV_OUT is 0. If the return status is CFLV_DISCARDED,
2674 // *LV_OUT is not modified.
2675 inline Compute_final_local_value_status
2676 compute_final_local_value_internal(unsigned int r_sym
,
2677 const Symbol_value
<size
>* lv_in
,
2678 Symbol_value
<size
>* lv_out
,
2680 const Output_sections
& out_sections
,
2681 const std::vector
<Address
>& out_offsets
,
2682 const Symbol_table
* symtab
);
2684 // The PLT offsets of local symbols.
2685 typedef Unordered_map
<unsigned int, unsigned int> Local_plt_offsets
;
2687 // Saved information for sections whose layout was deferred.
2688 struct Deferred_layout
2690 static const int shdr_size
= elfcpp::Elf_sizes
<size
>::shdr_size
;
2691 Deferred_layout(unsigned int shndx
, const char* name
,
2692 const unsigned char* pshdr
,
2693 unsigned int reloc_shndx
, unsigned int reloc_type
)
2694 : shndx_(shndx
), name_(name
), reloc_shndx_(reloc_shndx
),
2695 reloc_type_(reloc_type
)
2697 memcpy(this->shdr_data_
, pshdr
, shdr_size
);
2699 unsigned int shndx_
;
2701 unsigned int reloc_shndx_
;
2702 unsigned int reloc_type_
;
2703 unsigned char shdr_data_
[shdr_size
];
2706 // General access to the ELF file.
2707 elfcpp::Elf_file
<size
, big_endian
, Object
> elf_file_
;
2708 // Type of ELF file (ET_REL or ET_EXEC). ET_EXEC files are allowed
2709 // as input files only for the --just-symbols option.
2711 // Index of SHT_SYMTAB section.
2712 unsigned int symtab_shndx_
;
2713 // The number of local symbols.
2714 unsigned int local_symbol_count_
;
2715 // The number of local symbols which go into the output file.
2716 unsigned int output_local_symbol_count_
;
2717 // The number of local symbols which go into the output file's dynamic
2719 unsigned int output_local_dynsym_count_
;
2720 // The entries in the symbol table for the external symbols.
2722 // Number of symbols defined in object file itself.
2723 size_t defined_count_
;
2724 // File offset for local symbols (relative to start of symbol table).
2725 off_t local_symbol_offset_
;
2726 // File offset for local dynamic symbols (absolute).
2727 off_t local_dynsym_offset_
;
2728 // Values of local symbols.
2729 Local_values local_values_
;
2730 // PLT offsets for local symbols.
2731 Local_plt_offsets local_plt_offsets_
;
2732 // Table mapping discarded comdat sections to corresponding kept sections.
2733 Kept_comdat_section_table kept_comdat_sections_
;
2734 // Whether this object has a GNU style .eh_frame section.
2736 // If this object has a GNU style .eh_frame section that is discarded in
2737 // output, record the index here. Otherwise it is -1U.
2738 unsigned int discarded_eh_frame_shndx_
;
2739 // The list of sections whose layout was deferred.
2740 std::vector
<Deferred_layout
> deferred_layout_
;
2741 // The list of relocation sections whose layout was deferred.
2742 std::vector
<Deferred_layout
> deferred_layout_relocs_
;
2743 // For compressed debug sections, map section index to uncompressed size
2745 Compressed_section_map
* compressed_sections_
;
2748 // A class to manage the list of all objects.
2754 : relobj_list_(), dynobj_list_(), sonames_(), cref_(NULL
)
2757 // The type of the list of input relocateable objects.
2758 typedef std::vector
<Relobj
*> Relobj_list
;
2759 typedef Relobj_list::const_iterator Relobj_iterator
;
2761 // The type of the list of input dynamic objects.
2762 typedef std::vector
<Dynobj
*> Dynobj_list
;
2763 typedef Dynobj_list::const_iterator Dynobj_iterator
;
2765 // Add an object to the list. Return true if all is well, or false
2766 // if this object should be ignored.
2768 add_object(Object
*);
2770 // Start processing an archive.
2772 archive_start(Archive
*);
2774 // Stop processing an archive.
2776 archive_stop(Archive
*);
2778 // For each dynamic object, check whether we've seen all of its
2779 // explicit dependencies.
2781 check_dynamic_dependencies() const;
2783 // Return whether an object was found in the system library
2786 found_in_system_library_directory(const Object
*) const;
2788 // Print symbol counts.
2790 print_symbol_counts(const Symbol_table
*) const;
2792 // Print a cross reference table.
2794 print_cref(const Symbol_table
*, FILE*) const;
2796 // Iterate over all regular objects.
2799 relobj_begin() const
2800 { return this->relobj_list_
.begin(); }
2804 { return this->relobj_list_
.end(); }
2806 // Iterate over all dynamic objects.
2809 dynobj_begin() const
2810 { return this->dynobj_list_
.begin(); }
2814 { return this->dynobj_list_
.end(); }
2816 // Return whether we have seen any dynamic objects.
2819 { return !this->dynobj_list_
.empty(); }
2821 // Return the number of non dynamic objects.
2823 number_of_relobjs() const
2824 { return this->relobj_list_
.size(); }
2826 // Return the number of input objects.
2828 number_of_input_objects() const
2829 { return this->relobj_list_
.size() + this->dynobj_list_
.size(); }
2832 Input_objects(const Input_objects
&);
2833 Input_objects
& operator=(const Input_objects
&);
2835 // The list of ordinary objects included in the link.
2836 Relobj_list relobj_list_
;
2837 // The list of dynamic objects included in the link.
2838 Dynobj_list dynobj_list_
;
2839 // SONAMEs that we have seen.
2840 Unordered_set
<std::string
> sonames_
;
2841 // Manage cross-references if requested.
2845 // Some of the information we pass to the relocation routines. We
2846 // group this together to avoid passing a dozen different arguments.
2848 template<int size
, bool big_endian
>
2849 struct Relocate_info
2852 const Symbol_table
* symtab
;
2854 const Layout
* layout
;
2855 // Object being relocated.
2856 Sized_relobj_file
<size
, big_endian
>* object
;
2857 // Section index of relocation section.
2858 unsigned int reloc_shndx
;
2859 // Section header of relocation section.
2860 const unsigned char* reloc_shdr
;
2861 // Section index of section being relocated.
2862 unsigned int data_shndx
;
2863 // Section header of data section.
2864 const unsigned char* data_shdr
;
2866 // Return a string showing the location of a relocation. This is
2867 // only used for error messages.
2869 location(size_t relnum
, off_t reloffset
) const;
2872 // This is used to represent a section in an object and is used as the
2873 // key type for various section maps.
2874 typedef std::pair
<Object
*, unsigned int> Section_id
;
2876 // This is similar to Section_id but is used when the section
2877 // pointers are const.
2878 typedef std::pair
<const Object
*, unsigned int> Const_section_id
;
2880 // The hash value is based on the address of an object in memory during
2881 // linking. It is okay to use this for looking up sections but never use
2882 // this in an unordered container that we want to traverse in a repeatable
2885 struct Section_id_hash
2887 size_t operator()(const Section_id
& loc
) const
2888 { return reinterpret_cast<uintptr_t>(loc
.first
) ^ loc
.second
; }
2891 struct Const_section_id_hash
2893 size_t operator()(const Const_section_id
& loc
) const
2894 { return reinterpret_cast<uintptr_t>(loc
.first
) ^ loc
.second
; }
2897 // Return whether INPUT_FILE contains an ELF object start at file
2898 // offset OFFSET. This sets *START to point to a view of the start of
2899 // the file. It sets *READ_SIZE to the number of bytes in the view.
2902 is_elf_object(Input_file
* input_file
, off_t offset
,
2903 const unsigned char** start
, int* read_size
);
2905 // Return an Object appropriate for the input file. P is BYTES long,
2906 // and holds the ELF header. If PUNCONFIGURED is not NULL, then if
2907 // this sees an object the linker is not configured to support, it
2908 // sets *PUNCONFIGURED to true and returns NULL without giving an
2912 make_elf_object(const std::string
& name
, Input_file
*,
2913 off_t offset
, const unsigned char* p
,
2914 section_offset_type bytes
, bool* punconfigured
);
2916 } // end namespace gold
2918 #endif // !defined(GOLD_OBJECT_H)