1 // object.h -- support for an object file for linking in gold -*- C++ -*-
3 // Copyright (C) 2006-2015 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.
30 #include "elfcpp_file.h"
38 class General_options
;
44 class Output_section_data
;
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 // Type for mapping section index to uncompressed size and contents.
320 struct Compressed_section_info
322 section_size_type size
;
323 const unsigned char* contents
;
325 typedef std::map
<unsigned int, Compressed_section_info
> Compressed_section_map
;
327 template<int size
, bool big_endian
>
328 Compressed_section_map
*
329 build_compressed_section_map(const unsigned char* pshdrs
, unsigned int shnum
,
330 const char* names
, section_size_type names_size
,
331 Object
* obj
, bool decompress_if_needed
);
333 // Object is an abstract base class which represents either a 32-bit
334 // or a 64-bit input object. This can be a regular object file
335 // (ET_REL) or a shared object (ET_DYN).
340 typedef std::vector
<Symbol
*> Symbols
;
342 // NAME is the name of the object as we would report it to the user
343 // (e.g., libfoo.a(bar.o) if this is in an archive. INPUT_FILE is
344 // used to read the file. OFFSET is the offset within the input
345 // file--0 for a .o or .so file, something else for a .a file.
346 Object(const std::string
& name
, Input_file
* input_file
, bool is_dynamic
,
348 : name_(name
), input_file_(input_file
), offset_(offset
), shnum_(-1U),
349 is_dynamic_(is_dynamic
), is_needed_(false), uses_split_stack_(false),
350 has_no_split_stack_(false), no_export_(false),
351 is_in_system_directory_(false), as_needed_(false), xindex_(NULL
),
352 compressed_sections_(NULL
)
354 if (input_file
!= NULL
)
356 input_file
->file().add_object();
357 this->is_in_system_directory_
= input_file
->is_in_system_directory();
358 this->as_needed_
= input_file
->options().as_needed();
364 if (this->input_file_
!= NULL
)
365 this->input_file_
->file().remove_object();
368 // Return the name of the object as we would report it to the user.
371 { return this->name_
; }
373 // Get the offset into the file.
376 { return this->offset_
; }
378 // Return whether this is a dynamic object.
381 { return this->is_dynamic_
; }
383 // Return whether this object is needed--true if it is a dynamic
384 // object which defines some symbol referenced by a regular object.
385 // We keep the flag here rather than in Dynobj for convenience when
389 { return this->is_needed_
; }
391 // Record that this object is needed.
394 { this->is_needed_
= true; }
396 // Return whether this object was compiled with -fsplit-stack.
398 uses_split_stack() const
399 { return this->uses_split_stack_
; }
401 // Return whether this object contains any functions compiled with
402 // the no_split_stack attribute.
404 has_no_split_stack() const
405 { return this->has_no_split_stack_
; }
407 // Returns NULL for Objects that are not dynamic objects. This method
408 // is overridden in the Dynobj class.
411 { return this->do_dynobj(); }
413 // Returns NULL for Objects that are not plugin objects. This method
414 // is overridden in the Pluginobj class.
417 { return this->do_pluginobj(); }
419 // Get the file. We pass on const-ness.
423 gold_assert(this->input_file_
!= NULL
);
424 return this->input_file_
;
430 gold_assert(this->input_file_
!= NULL
);
431 return this->input_file_
;
434 // Lock the underlying file.
438 if (this->input_file_
!= NULL
)
439 this->input_file_
->file().lock(t
);
442 // Unlock the underlying file.
444 unlock(const Task
* t
)
446 if (this->input_file_
!= NULL
)
447 this->input_file()->file().unlock(t
);
450 // Return whether the underlying file is locked.
453 { return this->input_file_
!= NULL
&& this->input_file_
->file().is_locked(); }
455 // Return the token, so that the task can be queued.
459 if (this->input_file_
== NULL
)
461 return this->input_file()->file().token();
464 // Release the underlying file.
468 if (this->input_file_
!= NULL
)
469 this->input_file()->file().release();
472 // Return whether we should just read symbols from this file.
475 { return this->input_file()->just_symbols(); }
477 // Return whether this is an incremental object.
479 is_incremental() const
480 { return this->do_is_incremental(); }
482 // Return the last modified time of the file.
485 { return this->do_get_mtime(); }
487 // Get the number of sections.
490 { return this->shnum_
; }
492 // Return a view of the contents of a section. Set *PLEN to the
493 // size. CACHE is a hint as in File_read::get_view.
495 section_contents(unsigned int shndx
, section_size_type
* plen
, bool cache
);
497 // Adjust a symbol's section index as needed. SYMNDX is the index
498 // of the symbol and SHNDX is the symbol's section from
499 // get_st_shndx. This returns the section index. It sets
500 // *IS_ORDINARY to indicate whether this is a normal section index,
501 // rather than a special code between SHN_LORESERVE and
504 adjust_sym_shndx(unsigned int symndx
, unsigned int shndx
, bool* is_ordinary
)
506 if (shndx
< elfcpp::SHN_LORESERVE
)
508 else if (shndx
== elfcpp::SHN_XINDEX
)
510 if (this->xindex_
== NULL
)
511 this->xindex_
= this->do_initialize_xindex();
512 shndx
= this->xindex_
->sym_xindex_to_shndx(this, symndx
);
516 *is_ordinary
= false;
520 // Return the size of a section given a section index.
522 section_size(unsigned int shndx
)
523 { return this->do_section_size(shndx
); }
525 // Return the name of a section given a section index.
527 section_name(unsigned int shndx
) const
528 { return this->do_section_name(shndx
); }
530 // Return the section flags given a section index.
532 section_flags(unsigned int shndx
)
533 { return this->do_section_flags(shndx
); }
535 // Return the section entsize given a section index.
537 section_entsize(unsigned int shndx
)
538 { return this->do_section_entsize(shndx
); }
540 // Return the section address given a section index.
542 section_address(unsigned int shndx
)
543 { return this->do_section_address(shndx
); }
545 // Return the section type given a section index.
547 section_type(unsigned int shndx
)
548 { return this->do_section_type(shndx
); }
550 // Return the section link field given a section index.
552 section_link(unsigned int shndx
)
553 { return this->do_section_link(shndx
); }
555 // Return the section info field given a section index.
557 section_info(unsigned int shndx
)
558 { return this->do_section_info(shndx
); }
560 // Return the required section alignment given a section index.
562 section_addralign(unsigned int shndx
)
563 { return this->do_section_addralign(shndx
); }
565 // Return the output section given a section index.
567 output_section(unsigned int shndx
) const
568 { return this->do_output_section(shndx
); }
570 // Given a section index, return its address.
571 // The return value will be -1U if the section is specially mapped,
572 // such as a merge section.
574 output_section_address(unsigned int shndx
)
575 { return this->do_output_section_address(shndx
); }
577 // Given a section index, return the offset in the Output_section.
578 // The return value will be -1U if the section is specially mapped,
579 // such as a merge section.
581 output_section_offset(unsigned int shndx
) const
582 { return this->do_output_section_offset(shndx
); }
584 // Read the symbol information.
586 read_symbols(Read_symbols_data
* sd
)
587 { return this->do_read_symbols(sd
); }
589 // Pass sections which should be included in the link to the Layout
590 // object, and record where the sections go in the output file.
592 layout(Symbol_table
* symtab
, Layout
* layout
, Read_symbols_data
* sd
)
593 { this->do_layout(symtab
, layout
, sd
); }
595 // Add symbol information to the global symbol table.
597 add_symbols(Symbol_table
* symtab
, Read_symbols_data
* sd
, Layout
*layout
)
598 { this->do_add_symbols(symtab
, sd
, layout
); }
600 // Add symbol information to the global symbol table.
601 Archive::Should_include
602 should_include_member(Symbol_table
* symtab
, Layout
* layout
,
603 Read_symbols_data
* sd
, std::string
* why
)
604 { return this->do_should_include_member(symtab
, layout
, sd
, why
); }
606 // Iterate over global symbols, calling a visitor class V for each.
608 for_all_global_symbols(Read_symbols_data
* sd
,
609 Library_base::Symbol_visitor_base
* v
)
610 { return this->do_for_all_global_symbols(sd
, v
); }
612 // Iterate over local symbols, calling a visitor class V for each GOT offset
613 // associated with a local symbol.
615 for_all_local_got_entries(Got_offset_list::Visitor
* v
) const
616 { this->do_for_all_local_got_entries(v
); }
618 // Functions and types for the elfcpp::Elf_file interface. This
619 // permit us to use Object as the File template parameter for
622 // The View class is returned by view. It must support a single
623 // method, data(). This is trivial, because get_view does what we
628 View(const unsigned char* p
)
637 const unsigned char* p_
;
642 view(off_t file_offset
, section_size_type data_size
)
643 { return View(this->get_view(file_offset
, data_size
, true, true)); }
647 error(const char* format
, ...) const ATTRIBUTE_PRINTF_2
;
649 // A location in the file.
655 Location(off_t fo
, section_size_type ds
)
656 : file_offset(fo
), data_size(ds
)
660 // Get a View given a Location.
661 View
view(Location loc
)
662 { return View(this->get_view(loc
.file_offset
, loc
.data_size
, true, true)); }
664 // Get a view into the underlying file.
666 get_view(off_t start
, section_size_type size
, bool aligned
, bool cache
)
668 return this->input_file()->file().get_view(this->offset_
, start
, size
,
672 // Get a lasting view into the underlying file.
674 get_lasting_view(off_t start
, section_size_type size
, bool aligned
,
677 return this->input_file()->file().get_lasting_view(this->offset_
, start
,
678 size
, aligned
, cache
);
681 // Read data from the underlying file.
683 read(off_t start
, section_size_type size
, void* p
)
684 { this->input_file()->file().read(start
+ this->offset_
, size
, p
); }
686 // Read multiple data from the underlying file.
688 read_multiple(const File_read::Read_multiple
& rm
)
689 { this->input_file()->file().read_multiple(this->offset_
, rm
); }
691 // Stop caching views in the underlying file.
693 clear_view_cache_marks()
695 if (this->input_file_
!= NULL
)
696 this->input_file_
->file().clear_view_cache_marks();
699 // Get the number of global symbols defined by this object, and the
700 // number of the symbols whose final definition came from this
703 get_global_symbol_counts(const Symbol_table
* symtab
, size_t* defined
,
705 { this->do_get_global_symbol_counts(symtab
, defined
, used
); }
707 // Get the symbols defined in this object.
709 get_global_symbols() const
710 { return this->do_get_global_symbols(); }
712 // Set flag that this object was found in a system directory.
714 set_is_in_system_directory()
715 { this->is_in_system_directory_
= true; }
717 // Return whether this object was found in a system directory.
719 is_in_system_directory() const
720 { return this->is_in_system_directory_
; }
722 // Set flag that this object was linked with --as-needed.
725 { this->as_needed_
= true; }
727 // Return whether this object was linked with --as-needed.
730 { return this->as_needed_
; }
732 // Return whether we found this object by searching a directory.
735 { return this->input_file()->will_search_for(); }
739 { return this->no_export_
; }
742 set_no_export(bool value
)
743 { this->no_export_
= value
; }
746 section_is_compressed(unsigned int shndx
,
747 section_size_type
* uncompressed_size
) const
749 if (this->compressed_sections_
== NULL
)
751 Compressed_section_map::const_iterator p
=
752 this->compressed_sections_
->find(shndx
);
753 if (p
!= this->compressed_sections_
->end())
755 if (uncompressed_size
!= NULL
)
756 *uncompressed_size
= p
->second
.size
;
762 // Return a view of the decompressed contents of a section. Set *PLEN
763 // to the size. Set *IS_NEW to true if the contents need to be freed
766 decompressed_section_contents(unsigned int shndx
, section_size_type
* plen
,
769 // Discard any buffers of decompressed sections. This is done
770 // at the end of the Add_symbols task.
772 discard_decompressed_sections();
774 // Return the index of the first incremental relocation for symbol SYMNDX.
776 get_incremental_reloc_base(unsigned int symndx
) const
777 { return this->do_get_incremental_reloc_base(symndx
); }
779 // Return the number of incremental relocations for symbol SYMNDX.
781 get_incremental_reloc_count(unsigned int symndx
) const
782 { return this->do_get_incremental_reloc_count(symndx
); }
785 // Returns NULL for Objects that are not dynamic objects. This method
786 // is overridden in the Dynobj class.
791 // Returns NULL for Objects that are not plugin objects. This method
792 // is overridden in the Pluginobj class.
797 // Return TRUE if this is an incremental (unchanged) input file.
798 // We return FALSE by default; the incremental object classes
799 // override this method.
801 do_is_incremental() const
804 // Return the last modified time of the file. This method may be
805 // overridden for subclasses that don't use an actual file (e.g.,
806 // Incremental objects).
809 { return this->input_file()->file().get_mtime(); }
811 // Read the symbols--implemented by child class.
813 do_read_symbols(Read_symbols_data
*) = 0;
815 // Lay out sections--implemented by child class.
817 do_layout(Symbol_table
*, Layout
*, Read_symbols_data
*) = 0;
819 // Add symbol information to the global symbol table--implemented by
822 do_add_symbols(Symbol_table
*, Read_symbols_data
*, Layout
*) = 0;
824 virtual Archive::Should_include
825 do_should_include_member(Symbol_table
* symtab
, Layout
*, Read_symbols_data
*,
826 std::string
* why
) = 0;
828 // Iterate over global symbols, calling a visitor class V for each.
830 do_for_all_global_symbols(Read_symbols_data
* sd
,
831 Library_base::Symbol_visitor_base
* v
) = 0;
833 // Iterate over local symbols, calling a visitor class V for each GOT offset
834 // associated with a local symbol.
836 do_for_all_local_got_entries(Got_offset_list::Visitor
* v
) const = 0;
838 // Return the location of the contents of a section. Implemented by
840 virtual const unsigned char*
841 do_section_contents(unsigned int shndx
, section_size_type
* plen
,
844 // Get the size of a section--implemented by child class.
846 do_section_size(unsigned int shndx
) = 0;
848 // Get the name of a section--implemented by child class.
850 do_section_name(unsigned int shndx
) const = 0;
852 // Get section flags--implemented by child class.
854 do_section_flags(unsigned int shndx
) = 0;
856 // Get section entsize--implemented by child class.
858 do_section_entsize(unsigned int shndx
) = 0;
860 // Get section address--implemented by child class.
862 do_section_address(unsigned int shndx
) = 0;
864 // Get section type--implemented by child class.
866 do_section_type(unsigned int shndx
) = 0;
868 // Get section link field--implemented by child class.
870 do_section_link(unsigned int shndx
) = 0;
872 // Get section info field--implemented by child class.
874 do_section_info(unsigned int shndx
) = 0;
876 // Get section alignment--implemented by child class.
878 do_section_addralign(unsigned int shndx
) = 0;
880 // Return the output section given a section index--implemented
882 virtual Output_section
*
883 do_output_section(unsigned int) const
884 { gold_unreachable(); }
886 // Get the address of a section--implemented by child class.
888 do_output_section_address(unsigned int)
889 { gold_unreachable(); }
891 // Get the offset of a section--implemented by child class.
893 do_output_section_offset(unsigned int) const
894 { gold_unreachable(); }
896 // Return the Xindex structure to use.
898 do_initialize_xindex() = 0;
900 // Implement get_global_symbol_counts--implemented by child class.
902 do_get_global_symbol_counts(const Symbol_table
*, size_t*, size_t*) const = 0;
904 virtual const Symbols
*
905 do_get_global_symbols() const = 0;
907 // Set the number of sections.
910 { this->shnum_
= shnum
; }
912 // Functions used by both Sized_relobj_file and Sized_dynobj.
914 // Read the section data into a Read_symbols_data object.
915 template<int size
, bool big_endian
>
917 read_section_data(elfcpp::Elf_file
<size
, big_endian
, Object
>*,
920 // Find the section header with the given NAME. If HDR is non-NULL
921 // then it is a section header returned from a previous call to this
922 // function and the next section header with the same name will be
924 template<int size
, bool big_endian
>
926 find_shdr(const unsigned char* pshdrs
, const char* name
,
927 const char* names
, section_size_type names_size
,
928 const unsigned char* hdr
) const;
930 // Let the child class initialize the xindex object directly.
932 set_xindex(Xindex
* xindex
)
934 gold_assert(this->xindex_
== NULL
);
935 this->xindex_
= xindex
;
938 // If NAME is the name of a special .gnu.warning section, arrange
939 // for the warning to be issued. SHNDX is the section index.
940 // Return whether it is a warning section.
942 handle_gnu_warning_section(const char* name
, unsigned int shndx
,
945 // If NAME is the name of the special section which indicates that
946 // this object was compiled with -fsplit-stack, mark it accordingly,
947 // and return true. Otherwise return false.
949 handle_split_stack_section(const char* name
);
951 // Discard any buffers of decompressed sections. This is done
952 // at the end of the Add_symbols task.
954 do_discard_decompressed_sections()
957 // Return the index of the first incremental relocation for symbol SYMNDX--
958 // implemented by child class.
960 do_get_incremental_reloc_base(unsigned int) const
961 { gold_unreachable(); }
963 // Return the number of incremental relocations for symbol SYMNDX--
964 // implemented by child class.
966 do_get_incremental_reloc_count(unsigned int) const
967 { gold_unreachable(); }
970 set_compressed_sections(Compressed_section_map
* compressed_sections
)
971 { this->compressed_sections_
= compressed_sections
; }
973 Compressed_section_map
*
974 compressed_sections()
975 { return this->compressed_sections_
; }
978 // This class may not be copied.
979 Object(const Object
&);
980 Object
& operator=(const Object
&);
982 // Name of object as printed to user.
984 // For reading the file.
985 Input_file
* input_file_
;
986 // Offset within the file--0 for an object file, non-0 for an
989 // Number of input sections.
991 // Whether this is a dynamic object.
992 bool is_dynamic_
: 1;
993 // Whether this object is needed. This is only set for dynamic
994 // objects, and means that the object defined a symbol which was
995 // used by a reference from a regular object.
997 // Whether this object was compiled with -fsplit-stack.
998 bool uses_split_stack_
: 1;
999 // Whether this object contains any functions compiled with the
1000 // no_split_stack attribute.
1001 bool has_no_split_stack_
: 1;
1002 // True if exclude this object from automatic symbol export.
1003 // This is used only for archive objects.
1004 bool no_export_
: 1;
1005 // True if the object was found in a system directory.
1006 bool is_in_system_directory_
: 1;
1007 // True if the object was linked with --as-needed.
1008 bool as_needed_
: 1;
1009 // Many sections for objects with more than SHN_LORESERVE sections.
1011 // For compressed debug sections, map section index to uncompressed size
1013 Compressed_section_map
* compressed_sections_
;
1016 // A regular object (ET_REL). This is an abstract base class itself.
1017 // The implementation is the template class Sized_relobj_file.
1019 class Relobj
: public Object
1022 Relobj(const std::string
& name
, Input_file
* input_file
, off_t offset
= 0)
1023 : Object(name
, input_file
, false, offset
),
1025 map_to_relocatable_relocs_(NULL
),
1026 object_merge_map_(NULL
),
1027 relocs_must_follow_section_writes_(false),
1029 reloc_counts_(NULL
),
1031 first_dyn_reloc_(0),
1035 // During garbage collection, the Read_symbols_data pass for
1036 // each object is stored as layout needs to be done after
1037 // reloc processing.
1040 { return this->sd_
; }
1042 // Decides which section names have to be included in the worklist
1045 is_section_name_included(const char* name
);
1048 copy_symbols_data(Symbols_data
* gc_sd
, Read_symbols_data
* sd
,
1049 unsigned int section_header_size
);
1052 set_symbols_data(Symbols_data
* sd
)
1055 // During garbage collection, the Read_relocs pass for all objects
1056 // is done before scanning the relocs. In that case, this->rd_ is
1057 // used to store the information from Read_relocs for each object.
1058 // This data is also used to compute the list of relevant sections.
1061 { return this->rd_
; }
1064 set_relocs_data(Read_relocs_data
* rd
)
1068 is_output_section_offset_invalid(unsigned int shndx
) const = 0;
1072 read_relocs(Read_relocs_data
* rd
)
1073 { return this->do_read_relocs(rd
); }
1075 // Process the relocs, during garbage collection only.
1077 gc_process_relocs(Symbol_table
* symtab
, Layout
* layout
, Read_relocs_data
* rd
)
1078 { return this->do_gc_process_relocs(symtab
, layout
, rd
); }
1080 // Scan the relocs and adjust the symbol table.
1082 scan_relocs(Symbol_table
* symtab
, Layout
* layout
, Read_relocs_data
* rd
)
1083 { return this->do_scan_relocs(symtab
, layout
, rd
); }
1085 // Return the value of the local symbol whose index is SYMNDX, plus
1086 // ADDEND. ADDEND is passed in so that we can correctly handle the
1087 // section symbol for a merge section.
1089 local_symbol_value(unsigned int symndx
, uint64_t addend
) const
1090 { return this->do_local_symbol_value(symndx
, addend
); }
1092 // Return the PLT offset for a local symbol. It is an error to call
1093 // this if it doesn't have one.
1095 local_plt_offset(unsigned int symndx
) const
1096 { return this->do_local_plt_offset(symndx
); }
1098 // Return whether the local symbol SYMNDX has a GOT offset of type
1101 local_has_got_offset(unsigned int symndx
, unsigned int got_type
) const
1102 { return this->do_local_has_got_offset(symndx
, got_type
); }
1104 // Return the GOT offset of type GOT_TYPE of the local symbol
1105 // SYMNDX. It is an error to call this if the symbol does not have
1106 // a GOT offset of the specified type.
1108 local_got_offset(unsigned int symndx
, unsigned int got_type
) const
1109 { return this->do_local_got_offset(symndx
, got_type
); }
1111 // Set the GOT offset with type GOT_TYPE of the local symbol SYMNDX
1114 set_local_got_offset(unsigned int symndx
, unsigned int got_type
,
1115 unsigned int got_offset
)
1116 { this->do_set_local_got_offset(symndx
, got_type
, got_offset
); }
1118 // Return whether the local symbol SYMNDX is a TLS symbol.
1120 local_is_tls(unsigned int symndx
) const
1121 { return this->do_local_is_tls(symndx
); }
1123 // The number of local symbols in the input symbol table.
1124 virtual unsigned int
1125 local_symbol_count() const
1126 { return this->do_local_symbol_count(); }
1128 // The number of local symbols in the output symbol table.
1129 virtual unsigned int
1130 output_local_symbol_count() const
1131 { return this->do_output_local_symbol_count(); }
1133 // The file offset for local symbols in the output symbol table.
1135 local_symbol_offset() const
1136 { return this->do_local_symbol_offset(); }
1138 // Initial local symbol processing: count the number of local symbols
1139 // in the output symbol table and dynamic symbol table; add local symbol
1140 // names to *POOL and *DYNPOOL.
1142 count_local_symbols(Stringpool_template
<char>* pool
,
1143 Stringpool_template
<char>* dynpool
)
1144 { return this->do_count_local_symbols(pool
, dynpool
); }
1146 // Set the values of the local symbols, set the output symbol table
1147 // indexes for the local variables, and set the offset where local
1148 // symbol information will be stored. Returns the new local symbol index.
1150 finalize_local_symbols(unsigned int index
, off_t off
, Symbol_table
* symtab
)
1151 { return this->do_finalize_local_symbols(index
, off
, symtab
); }
1153 // Set the output dynamic symbol table indexes for the local variables.
1155 set_local_dynsym_indexes(unsigned int index
)
1156 { return this->do_set_local_dynsym_indexes(index
); }
1158 // Set the offset where local dynamic symbol information will be stored.
1160 set_local_dynsym_offset(off_t off
)
1161 { return this->do_set_local_dynsym_offset(off
); }
1163 // Record a dynamic relocation against an input section from this object.
1165 add_dyn_reloc(unsigned int index
)
1167 if (this->dyn_reloc_count_
== 0)
1168 this->first_dyn_reloc_
= index
;
1169 ++this->dyn_reloc_count_
;
1172 // Return the index of the first dynamic relocation.
1174 first_dyn_reloc() const
1175 { return this->first_dyn_reloc_
; }
1177 // Return the count of dynamic relocations.
1179 dyn_reloc_count() const
1180 { return this->dyn_reloc_count_
; }
1182 // Relocate the input sections and write out the local symbols.
1184 relocate(const Symbol_table
* symtab
, const Layout
* layout
, Output_file
* of
)
1185 { return this->do_relocate(symtab
, layout
, of
); }
1187 // Return whether an input section is being included in the link.
1189 is_section_included(unsigned int shndx
) const
1191 gold_assert(shndx
< this->output_sections_
.size());
1192 return this->output_sections_
[shndx
] != NULL
;
1195 // The output section of the input section with index SHNDX.
1196 // This is only used currently to remove a section from the link in
1199 set_output_section(unsigned int shndx
, Output_section
* os
)
1201 gold_assert(shndx
< this->output_sections_
.size());
1202 this->output_sections_
[shndx
] = os
;
1205 // Set the offset of an input section within its output section.
1207 set_section_offset(unsigned int shndx
, uint64_t off
)
1208 { this->do_set_section_offset(shndx
, off
); }
1210 // Return true if we need to wait for output sections to be written
1211 // before we can apply relocations. This is true if the object has
1212 // any relocations for sections which require special handling, such
1213 // as the exception frame section.
1215 relocs_must_follow_section_writes() const
1216 { return this->relocs_must_follow_section_writes_
; }
1219 get_or_create_merge_map();
1223 initialize_input_to_output_map(unsigned int shndx
,
1224 typename
elfcpp::Elf_types
<size
>::Elf_Addr starting_address
,
1225 Unordered_map
<section_offset_type
,
1226 typename
elfcpp::Elf_types
<size
>::Elf_Addr
>* output_address
) const;
1229 add_merge_mapping(Output_section_data
*output_data
,
1230 unsigned int shndx
, section_offset_type offset
,
1231 section_size_type length
,
1232 section_offset_type output_offset
);
1235 merge_output_offset(unsigned int shndx
, section_offset_type offset
,
1236 section_offset_type
*poutput
) const;
1238 const Output_section_data
*
1239 find_merge_section(unsigned int shndx
) const;
1241 // Record the relocatable reloc info for an input reloc section.
1243 set_relocatable_relocs(unsigned int reloc_shndx
, Relocatable_relocs
* rr
)
1245 gold_assert(reloc_shndx
< this->shnum());
1246 (*this->map_to_relocatable_relocs_
)[reloc_shndx
] = rr
;
1249 // Get the relocatable reloc info for an input reloc section.
1251 relocatable_relocs(unsigned int reloc_shndx
)
1253 gold_assert(reloc_shndx
< this->shnum());
1254 return (*this->map_to_relocatable_relocs_
)[reloc_shndx
];
1257 // Layout sections whose layout was deferred while waiting for
1258 // input files from a plugin.
1260 layout_deferred_sections(Layout
* layout
)
1261 { this->do_layout_deferred_sections(layout
); }
1263 // Return the index of the first incremental relocation for symbol SYMNDX.
1264 virtual unsigned int
1265 do_get_incremental_reloc_base(unsigned int symndx
) const
1266 { return this->reloc_bases_
[symndx
]; }
1268 // Return the number of incremental relocations for symbol SYMNDX.
1269 virtual unsigned int
1270 do_get_incremental_reloc_count(unsigned int symndx
) const
1271 { return this->reloc_counts_
[symndx
]; }
1273 // Return the word size of the object file.
1276 { return this->do_elfsize(); }
1278 // Return TRUE if this is a big-endian object file.
1280 is_big_endian() const
1281 { return this->do_is_big_endian(); }
1284 // The output section to be used for each input section, indexed by
1285 // the input section number. The output section is NULL if the
1286 // input section is to be discarded.
1287 typedef std::vector
<Output_section
*> Output_sections
;
1289 // Read the relocs--implemented by child class.
1291 do_read_relocs(Read_relocs_data
*) = 0;
1293 // Process the relocs--implemented by child class.
1295 do_gc_process_relocs(Symbol_table
*, Layout
*, Read_relocs_data
*) = 0;
1297 // Scan the relocs--implemented by child class.
1299 do_scan_relocs(Symbol_table
*, Layout
*, Read_relocs_data
*) = 0;
1301 // Return the value of a local symbol.
1303 do_local_symbol_value(unsigned int symndx
, uint64_t addend
) const = 0;
1305 // Return the PLT offset of a local symbol.
1306 virtual unsigned int
1307 do_local_plt_offset(unsigned int symndx
) const = 0;
1309 // Return whether a local symbol has a GOT offset of a given type.
1311 do_local_has_got_offset(unsigned int symndx
,
1312 unsigned int got_type
) const = 0;
1314 // Return the GOT offset of a given type of a local symbol.
1315 virtual unsigned int
1316 do_local_got_offset(unsigned int symndx
, unsigned int got_type
) const = 0;
1318 // Set the GOT offset with a given type for a local symbol.
1320 do_set_local_got_offset(unsigned int symndx
, unsigned int got_type
,
1321 unsigned int got_offset
) = 0;
1323 // Return whether local symbol SYMNDX is a TLS symbol.
1325 do_local_is_tls(unsigned int symndx
) const = 0;
1327 // Return the number of local symbols--implemented by child class.
1328 virtual unsigned int
1329 do_local_symbol_count() const = 0;
1331 // Return the number of output local symbols--implemented by child class.
1332 virtual unsigned int
1333 do_output_local_symbol_count() const = 0;
1335 // Return the file offset for local symbols--implemented by child class.
1337 do_local_symbol_offset() const = 0;
1339 // Count local symbols--implemented by child class.
1341 do_count_local_symbols(Stringpool_template
<char>*,
1342 Stringpool_template
<char>*) = 0;
1344 // Finalize the local symbols. Set the output symbol table indexes
1345 // for the local variables, and set the offset where local symbol
1346 // information will be stored.
1347 virtual unsigned int
1348 do_finalize_local_symbols(unsigned int, off_t
, Symbol_table
*) = 0;
1350 // Set the output dynamic symbol table indexes for the local variables.
1351 virtual unsigned int
1352 do_set_local_dynsym_indexes(unsigned int) = 0;
1354 // Set the offset where local dynamic symbol information will be stored.
1355 virtual unsigned int
1356 do_set_local_dynsym_offset(off_t
) = 0;
1358 // Relocate the input sections and write out the local
1359 // symbols--implemented by child class.
1361 do_relocate(const Symbol_table
* symtab
, const Layout
*, Output_file
* of
) = 0;
1363 // Set the offset of a section--implemented by child class.
1365 do_set_section_offset(unsigned int shndx
, uint64_t off
) = 0;
1367 // Layout sections whose layout was deferred while waiting for
1368 // input files from a plugin--implemented by child class.
1370 do_layout_deferred_sections(Layout
*) = 0;
1372 // Given a section index, return the corresponding Output_section.
1373 // The return value will be NULL if the section is not included in
1376 do_output_section(unsigned int shndx
) const
1378 gold_assert(shndx
< this->output_sections_
.size());
1379 return this->output_sections_
[shndx
];
1382 // Return the vector mapping input sections to output sections.
1385 { return this->output_sections_
; }
1387 const Output_sections
&
1388 output_sections() const
1389 { return this->output_sections_
; }
1391 // Set the size of the relocatable relocs array.
1393 size_relocatable_relocs()
1395 this->map_to_relocatable_relocs_
=
1396 new std::vector
<Relocatable_relocs
*>(this->shnum());
1399 // Record that we must wait for the output sections to be written
1400 // before applying relocations.
1402 set_relocs_must_follow_section_writes()
1403 { this->relocs_must_follow_section_writes_
= true; }
1405 // Allocate the array for counting incremental relocations.
1407 allocate_incremental_reloc_counts()
1409 unsigned int nsyms
= this->do_get_global_symbols()->size();
1410 this->reloc_counts_
= new unsigned int[nsyms
];
1411 gold_assert(this->reloc_counts_
!= NULL
);
1412 memset(this->reloc_counts_
, 0, nsyms
* sizeof(unsigned int));
1415 // Record a relocation in this object referencing global symbol SYMNDX.
1416 // Used for tracking incremental link information.
1418 count_incremental_reloc(unsigned int symndx
)
1420 unsigned int nsyms
= this->do_get_global_symbols()->size();
1421 gold_assert(symndx
< nsyms
);
1422 gold_assert(this->reloc_counts_
!= NULL
);
1423 ++this->reloc_counts_
[symndx
];
1426 // Finalize the incremental relocation information.
1428 finalize_incremental_relocs(Layout
* layout
, bool clear_counts
);
1430 // Return the index of the next relocation to be written for global symbol
1431 // SYMNDX. Only valid after finalize_incremental_relocs() has been called.
1433 next_incremental_reloc_index(unsigned int symndx
)
1435 unsigned int nsyms
= this->do_get_global_symbols()->size();
1437 gold_assert(this->reloc_counts_
!= NULL
);
1438 gold_assert(this->reloc_bases_
!= NULL
);
1439 gold_assert(symndx
< nsyms
);
1441 unsigned int counter
= this->reloc_counts_
[symndx
]++;
1442 return this->reloc_bases_
[symndx
] + counter
;
1445 // Return the word size of the object file--
1446 // implemented by child class.
1448 do_elfsize() const = 0;
1450 // Return TRUE if this is a big-endian object file--
1451 // implemented by child class.
1453 do_is_big_endian() const = 0;
1456 // Mapping from input sections to output section.
1457 Output_sections output_sections_
;
1458 // Mapping from input section index to the information recorded for
1459 // the relocations. This is only used for a relocatable link.
1460 std::vector
<Relocatable_relocs
*>* map_to_relocatable_relocs_
;
1461 // Mappings for merge sections. This is managed by the code in the
1463 Object_merge_map
* object_merge_map_
;
1464 // Whether we need to wait for output sections to be written before
1465 // we can apply relocations.
1466 bool relocs_must_follow_section_writes_
;
1467 // Used to store the relocs data computed by the Read_relocs pass.
1468 // Used during garbage collection of unused sections.
1469 Read_relocs_data
* rd_
;
1470 // Used to store the symbols data computed by the Read_symbols pass.
1471 // Again used during garbage collection when laying out referenced
1473 gold::Symbols_data
* sd_
;
1474 // Per-symbol counts of relocations, for incremental links.
1475 unsigned int* reloc_counts_
;
1476 // Per-symbol base indexes of relocations, for incremental links.
1477 unsigned int* reloc_bases_
;
1478 // Index of the first dynamic relocation for this object.
1479 unsigned int first_dyn_reloc_
;
1480 // Count of dynamic relocations for this object.
1481 unsigned int dyn_reloc_count_
;
1484 // This class is used to handle relocations against a section symbol
1485 // in an SHF_MERGE section. For such a symbol, we need to know the
1486 // addend of the relocation before we can determine the final value.
1487 // The addend gives us the location in the input section, and we can
1488 // determine how it is mapped to the output section. For a
1489 // non-section symbol, we apply the addend to the final value of the
1490 // symbol; that is done in finalize_local_symbols, and does not use
1494 class Merged_symbol_value
1497 typedef typename
elfcpp::Elf_types
<size
>::Elf_Addr Value
;
1499 // We use a hash table to map offsets in the input section to output
1501 typedef Unordered_map
<section_offset_type
, Value
> Output_addresses
;
1503 Merged_symbol_value(Value input_value
, Value output_start_address
)
1504 : input_value_(input_value
), output_start_address_(output_start_address
),
1508 // Initialize the hash table.
1510 initialize_input_to_output_map(const Relobj
*, unsigned int input_shndx
);
1512 // Release the hash table to save space.
1514 free_input_to_output_map()
1515 { this->output_addresses_
.clear(); }
1517 // Get the output value corresponding to an addend. The object and
1518 // input section index are passed in because the caller will have
1519 // them; otherwise we could store them here.
1521 value(const Relobj
* object
, unsigned int input_shndx
, Value addend
) const
1523 // This is a relocation against a section symbol. ADDEND is the
1524 // offset in the section. The result should be the start of some
1525 // merge area. If the object file wants something else, it should
1526 // use a regular symbol rather than a section symbol.
1527 // Unfortunately, PR 6658 shows a case in which the object file
1528 // refers to the section symbol, but uses a negative ADDEND to
1529 // compensate for a PC relative reloc. We can't handle the
1530 // general case. However, we can handle the special case of a
1531 // negative addend, by assuming that it refers to the start of the
1532 // section. Of course, that means that we have to guess when
1533 // ADDEND is negative. It is normal to see a 32-bit value here
1534 // even when the template parameter size is 64, as 64-bit object
1535 // file formats have 32-bit relocations. We know this is a merge
1536 // section, so we know it has to fit into memory. So we assume
1537 // that we won't see a value larger than a large 32-bit unsigned
1538 // value. This will break objects with very very large merge
1539 // sections; they probably break in other ways anyhow.
1540 Value input_offset
= this->input_value_
;
1541 if (addend
< 0xffffff00)
1543 input_offset
+= addend
;
1546 typename
Output_addresses::const_iterator p
=
1547 this->output_addresses_
.find(input_offset
);
1548 if (p
!= this->output_addresses_
.end())
1549 return p
->second
+ addend
;
1551 return (this->value_from_output_section(object
, input_shndx
, input_offset
)
1556 // Get the output value for an input offset if we couldn't find it
1557 // in the hash table.
1559 value_from_output_section(const Relobj
*, unsigned int input_shndx
,
1560 Value input_offset
) const;
1562 // The value of the section symbol in the input file. This is
1563 // normally zero, but could in principle be something else.
1565 // The start address of this merged section in the output file.
1566 Value output_start_address_
;
1567 // A hash table which maps offsets in the input section to output
1568 // addresses. This only maps specific offsets, not all offsets.
1569 Output_addresses output_addresses_
;
1572 // This POD class is holds the value of a symbol. This is used for
1573 // local symbols, and for all symbols during relocation processing.
1574 // For special sections, such as SHF_MERGE sections, this calls a
1575 // function to get the final symbol value.
1581 typedef typename
elfcpp::Elf_types
<size
>::Elf_Addr Value
;
1584 : output_symtab_index_(0), output_dynsym_index_(-1U), input_shndx_(0),
1585 is_ordinary_shndx_(false), is_section_symbol_(false),
1586 is_tls_symbol_(false), is_ifunc_symbol_(false), has_output_value_(true)
1587 { this->u_
.value
= 0; }
1591 if (!this->has_output_value_
)
1592 delete this->u_
.merged_symbol_value
;
1595 // Get the value of this symbol. OBJECT is the object in which this
1596 // symbol is defined, and ADDEND is an addend to add to the value.
1597 template<bool big_endian
>
1599 value(const Sized_relobj_file
<size
, big_endian
>* object
, Value addend
) const
1601 if (this->has_output_value_
)
1602 return this->u_
.value
+ addend
;
1605 gold_assert(this->is_ordinary_shndx_
);
1606 return this->u_
.merged_symbol_value
->value(object
, this->input_shndx_
,
1611 // Set the value of this symbol in the output symbol table.
1613 set_output_value(Value value
)
1614 { this->u_
.value
= value
; }
1616 // For a section symbol in a merged section, we need more
1619 set_merged_symbol_value(Merged_symbol_value
<size
>* msv
)
1621 gold_assert(this->is_section_symbol_
);
1622 this->has_output_value_
= false;
1623 this->u_
.merged_symbol_value
= msv
;
1626 // Initialize the input to output map for a section symbol in a
1627 // merged section. We also initialize the value of a non-section
1628 // symbol in a merged section.
1630 initialize_input_to_output_map(const Relobj
* object
)
1632 if (!this->has_output_value_
)
1634 gold_assert(this->is_section_symbol_
&& this->is_ordinary_shndx_
);
1635 Merged_symbol_value
<size
>* msv
= this->u_
.merged_symbol_value
;
1636 msv
->initialize_input_to_output_map(object
, this->input_shndx_
);
1640 // Free the input to output map for a section symbol in a merged
1643 free_input_to_output_map()
1645 if (!this->has_output_value_
)
1646 this->u_
.merged_symbol_value
->free_input_to_output_map();
1649 // Set the value of the symbol from the input file. This is only
1650 // called by count_local_symbols, to communicate the value to
1651 // finalize_local_symbols.
1653 set_input_value(Value value
)
1654 { this->u_
.value
= value
; }
1656 // Return the input value. This is only called by
1657 // finalize_local_symbols and (in special cases) relocate_section.
1660 { return this->u_
.value
; }
1662 // Return whether we have set the index in the output symbol table
1665 is_output_symtab_index_set() const
1667 return (this->output_symtab_index_
!= 0
1668 && this->output_symtab_index_
!= -2U);
1671 // Return whether this symbol may be discarded from the normal
1674 may_be_discarded_from_output_symtab() const
1676 gold_assert(!this->is_output_symtab_index_set());
1677 return this->output_symtab_index_
!= -2U;
1680 // Return whether this symbol has an entry in the output symbol
1683 has_output_symtab_entry() const
1685 gold_assert(this->is_output_symtab_index_set());
1686 return this->output_symtab_index_
!= -1U;
1689 // Return the index in the output symbol table.
1691 output_symtab_index() const
1693 gold_assert(this->is_output_symtab_index_set()
1694 && this->output_symtab_index_
!= -1U);
1695 return this->output_symtab_index_
;
1698 // Set the index in the output symbol table.
1700 set_output_symtab_index(unsigned int i
)
1702 gold_assert(!this->is_output_symtab_index_set());
1703 gold_assert(i
!= 0 && i
!= -1U && i
!= -2U);
1704 this->output_symtab_index_
= i
;
1707 // Record that this symbol should not go into the output symbol
1710 set_no_output_symtab_entry()
1712 gold_assert(this->output_symtab_index_
== 0);
1713 this->output_symtab_index_
= -1U;
1716 // Record that this symbol must go into the output symbol table,
1717 // because it there is a relocation that uses it.
1719 set_must_have_output_symtab_entry()
1721 gold_assert(!this->is_output_symtab_index_set());
1722 this->output_symtab_index_
= -2U;
1725 // Set the index in the output dynamic symbol table.
1727 set_needs_output_dynsym_entry()
1729 gold_assert(!this->is_section_symbol());
1730 this->output_dynsym_index_
= 0;
1733 // Return whether this symbol should go into the dynamic symbol
1736 needs_output_dynsym_entry() const
1738 return this->output_dynsym_index_
!= -1U;
1741 // Return whether this symbol has an entry in the dynamic symbol
1744 has_output_dynsym_entry() const
1746 gold_assert(this->output_dynsym_index_
!= 0);
1747 return this->output_dynsym_index_
!= -1U;
1750 // Record that this symbol should go into the dynamic symbol table.
1752 set_output_dynsym_index(unsigned int i
)
1754 gold_assert(this->output_dynsym_index_
== 0);
1755 gold_assert(i
!= 0 && i
!= -1U);
1756 this->output_dynsym_index_
= i
;
1759 // Return the index in the output dynamic symbol table.
1761 output_dynsym_index() const
1763 gold_assert(this->output_dynsym_index_
!= 0
1764 && this->output_dynsym_index_
!= -1U);
1765 return this->output_dynsym_index_
;
1768 // Set the index of the input section in the input file.
1770 set_input_shndx(unsigned int i
, bool is_ordinary
)
1772 this->input_shndx_
= i
;
1773 // input_shndx_ field is a bitfield, so make sure that the value
1775 gold_assert(this->input_shndx_
== i
);
1776 this->is_ordinary_shndx_
= is_ordinary
;
1779 // Return the index of the input section in the input file.
1781 input_shndx(bool* is_ordinary
) const
1783 *is_ordinary
= this->is_ordinary_shndx_
;
1784 return this->input_shndx_
;
1787 // Whether this is a section symbol.
1789 is_section_symbol() const
1790 { return this->is_section_symbol_
; }
1792 // Record that this is a section symbol.
1794 set_is_section_symbol()
1796 gold_assert(!this->needs_output_dynsym_entry());
1797 this->is_section_symbol_
= true;
1800 // Record that this is a TLS symbol.
1803 { this->is_tls_symbol_
= true; }
1805 // Return true if this is a TLS symbol.
1807 is_tls_symbol() const
1808 { return this->is_tls_symbol_
; }
1810 // Record that this is an IFUNC symbol.
1812 set_is_ifunc_symbol()
1813 { this->is_ifunc_symbol_
= true; }
1815 // Return true if this is an IFUNC symbol.
1817 is_ifunc_symbol() const
1818 { return this->is_ifunc_symbol_
; }
1820 // Return true if this has output value.
1822 has_output_value() const
1823 { return this->has_output_value_
; }
1826 // The index of this local symbol in the output symbol table. This
1827 // will be 0 if no value has been assigned yet, and the symbol may
1828 // be omitted. This will be -1U if the symbol should not go into
1829 // the symbol table. This will be -2U if the symbol must go into
1830 // the symbol table, but no index has been assigned yet.
1831 unsigned int output_symtab_index_
;
1832 // The index of this local symbol in the dynamic symbol table. This
1833 // will be -1U if the symbol should not go into the symbol table.
1834 unsigned int output_dynsym_index_
;
1835 // The section index in the input file in which this symbol is
1837 unsigned int input_shndx_
: 27;
1838 // Whether the section index is an ordinary index, not a special
1840 bool is_ordinary_shndx_
: 1;
1841 // Whether this is a STT_SECTION symbol.
1842 bool is_section_symbol_
: 1;
1843 // Whether this is a STT_TLS symbol.
1844 bool is_tls_symbol_
: 1;
1845 // Whether this is a STT_GNU_IFUNC symbol.
1846 bool is_ifunc_symbol_
: 1;
1847 // Whether this symbol has a value for the output file. This is
1848 // normally set to true during Layout::finalize, by
1849 // finalize_local_symbols. It will be false for a section symbol in
1850 // a merge section, as for such symbols we can not determine the
1851 // value to use in a relocation until we see the addend.
1852 bool has_output_value_
: 1;
1855 // This is used if has_output_value_ is true. Between
1856 // count_local_symbols and finalize_local_symbols, this is the
1857 // value in the input file. After finalize_local_symbols, it is
1858 // the value in the output file.
1860 // This is used if has_output_value_ is false. It points to the
1861 // information we need to get the value for a merge section.
1862 Merged_symbol_value
<size
>* merged_symbol_value
;
1866 // This type is used to modify relocations for -fsplit-stack. It is
1867 // indexed by relocation index, and means that the relocation at that
1868 // index should use the symbol from the vector, rather than the one
1869 // indicated by the relocation.
1871 class Reloc_symbol_changes
1874 Reloc_symbol_changes(size_t count
)
1879 set(size_t i
, Symbol
* sym
)
1880 { this->vec_
[i
] = sym
; }
1883 operator[](size_t i
) const
1884 { return this->vec_
[i
]; }
1887 std::vector
<Symbol
*> vec_
;
1890 // Abstract base class for a regular object file, either a real object file
1891 // or an incremental (unchanged) object. This is size and endian specific.
1893 template<int size
, bool big_endian
>
1894 class Sized_relobj
: public Relobj
1897 typedef typename
elfcpp::Elf_types
<size
>::Elf_Addr Address
;
1898 typedef Relobj::Symbols Symbols
;
1900 static const Address invalid_address
= static_cast<Address
>(0) - 1;
1902 Sized_relobj(const std::string
& name
, Input_file
* input_file
)
1903 : Relobj(name
, input_file
), local_got_offsets_(), section_offsets_()
1906 Sized_relobj(const std::string
& name
, Input_file
* input_file
,
1908 : Relobj(name
, input_file
, offset
), local_got_offsets_(), section_offsets_()
1914 // If this is a regular object, return a pointer to the Sized_relobj_file
1915 // object. Otherwise, return NULL.
1916 virtual Sized_relobj_file
<size
, big_endian
>*
1920 const virtual Sized_relobj_file
<size
, big_endian
>*
1921 sized_relobj() const
1924 // Checks if the offset of input section SHNDX within its output
1925 // section is invalid.
1927 is_output_section_offset_invalid(unsigned int shndx
) const
1928 { return this->get_output_section_offset(shndx
) == invalid_address
; }
1930 // Get the offset of input section SHNDX within its output section.
1931 // This is -1 if the input section requires a special mapping, such
1932 // as a merge section. The output section can be found in the
1933 // output_sections_ field of the parent class Relobj.
1935 get_output_section_offset(unsigned int shndx
) const
1937 gold_assert(shndx
< this->section_offsets_
.size());
1938 return this->section_offsets_
[shndx
];
1941 // Iterate over local symbols, calling a visitor class V for each GOT offset
1942 // associated with a local symbol.
1944 do_for_all_local_got_entries(Got_offset_list::Visitor
* v
) const;
1947 typedef Relobj::Output_sections Output_sections
;
1949 // Clear the local symbol information.
1952 { this->local_got_offsets_
.clear(); }
1954 // Return the vector of section offsets.
1955 std::vector
<Address
>&
1957 { return this->section_offsets_
; }
1959 // Get the address of an output section.
1961 do_output_section_address(unsigned int shndx
);
1963 // Get the offset of a section.
1965 do_output_section_offset(unsigned int shndx
) const
1967 Address off
= this->get_output_section_offset(shndx
);
1968 if (off
== invalid_address
)
1973 // Set the offset of a section.
1975 do_set_section_offset(unsigned int shndx
, uint64_t off
)
1977 gold_assert(shndx
< this->section_offsets_
.size());
1978 this->section_offsets_
[shndx
] =
1979 (off
== static_cast<uint64_t>(-1)
1981 : convert_types
<Address
, uint64_t>(off
));
1984 // Return whether the local symbol SYMNDX has a GOT offset of type
1987 do_local_has_got_offset(unsigned int symndx
, unsigned int got_type
) const
1989 Local_got_offsets::const_iterator p
=
1990 this->local_got_offsets_
.find(symndx
);
1991 return (p
!= this->local_got_offsets_
.end()
1992 && p
->second
->get_offset(got_type
) != -1U);
1995 // Return the GOT offset of type GOT_TYPE of the local symbol
1998 do_local_got_offset(unsigned int symndx
, unsigned int got_type
) const
2000 Local_got_offsets::const_iterator p
=
2001 this->local_got_offsets_
.find(symndx
);
2002 gold_assert(p
!= this->local_got_offsets_
.end());
2003 unsigned int off
= p
->second
->get_offset(got_type
);
2004 gold_assert(off
!= -1U);
2008 // Set the GOT offset with type GOT_TYPE of the local symbol SYMNDX
2011 do_set_local_got_offset(unsigned int symndx
, unsigned int got_type
,
2012 unsigned int got_offset
)
2014 Local_got_offsets::const_iterator p
=
2015 this->local_got_offsets_
.find(symndx
);
2016 if (p
!= this->local_got_offsets_
.end())
2017 p
->second
->set_offset(got_type
, got_offset
);
2020 Got_offset_list
* g
= new Got_offset_list(got_type
, got_offset
);
2021 std::pair
<Local_got_offsets::iterator
, bool> ins
=
2022 this->local_got_offsets_
.insert(std::make_pair(symndx
, g
));
2023 gold_assert(ins
.second
);
2027 // Return the word size of the object file.
2032 // Return TRUE if this is a big-endian object file.
2034 do_is_big_endian() const
2035 { return big_endian
; }
2038 // The GOT offsets of local symbols. This map also stores GOT offsets
2039 // for tp-relative offsets for TLS symbols.
2040 typedef Unordered_map
<unsigned int, Got_offset_list
*> Local_got_offsets
;
2042 // GOT offsets for local non-TLS symbols, and tp-relative offsets
2043 // for TLS symbols, indexed by symbol number.
2044 Local_got_offsets local_got_offsets_
;
2045 // For each input section, the offset of the input section in its
2046 // output section. This is INVALID_ADDRESS if the input section requires a
2048 std::vector
<Address
> section_offsets_
;
2051 // A regular object file. This is size and endian specific.
2053 template<int size
, bool big_endian
>
2054 class Sized_relobj_file
: public Sized_relobj
<size
, big_endian
>
2057 typedef typename
elfcpp::Elf_types
<size
>::Elf_Addr Address
;
2058 typedef typename Sized_relobj
<size
, big_endian
>::Symbols Symbols
;
2059 typedef std::vector
<Symbol_value
<size
> > Local_values
;
2061 static const Address invalid_address
= static_cast<Address
>(0) - 1;
2063 enum Compute_final_local_value_status
2067 // An error occurred.
2069 // The local symbol has no output section.
2073 Sized_relobj_file(const std::string
& name
,
2074 Input_file
* input_file
,
2076 const typename
elfcpp::Ehdr
<size
, big_endian
>&);
2078 ~Sized_relobj_file();
2080 // Set up the object file based on TARGET.
2083 { this->do_setup(); }
2085 // Return a pointer to the Sized_relobj_file object.
2086 Sized_relobj_file
<size
, big_endian
>*
2090 const Sized_relobj_file
<size
, big_endian
>*
2091 sized_relobj() const
2094 // Return the ELF file type.
2097 { return this->e_type_
; }
2099 // Return the number of symbols. This is only valid after
2100 // Object::add_symbols has been called.
2102 symbol_count() const
2103 { return this->local_symbol_count_
+ this->symbols_
.size(); }
2105 // If SYM is the index of a global symbol in the object file's
2106 // symbol table, return the Symbol object. Otherwise, return NULL.
2108 global_symbol(unsigned int sym
) const
2110 if (sym
>= this->local_symbol_count_
)
2112 gold_assert(sym
- this->local_symbol_count_
< this->symbols_
.size());
2113 return this->symbols_
[sym
- this->local_symbol_count_
];
2118 // Return the section index of symbol SYM. Set *VALUE to its value
2119 // in the object file. Set *IS_ORDINARY if this is an ordinary
2120 // section index, not a special code between SHN_LORESERVE and
2121 // SHN_HIRESERVE. Note that for a symbol which is not defined in
2122 // this object file, this will set *VALUE to 0 and return SHN_UNDEF;
2123 // it will not return the final value of the symbol in the link.
2125 symbol_section_and_value(unsigned int sym
, Address
* value
, bool* is_ordinary
);
2127 // Return a pointer to the Symbol_value structure which holds the
2128 // value of a local symbol.
2129 const Symbol_value
<size
>*
2130 local_symbol(unsigned int sym
) const
2132 gold_assert(sym
< this->local_values_
.size());
2133 return &this->local_values_
[sym
];
2136 // Return the index of local symbol SYM in the ordinary symbol
2137 // table. A value of -1U means that the symbol is not being output.
2139 symtab_index(unsigned int sym
) const
2141 gold_assert(sym
< this->local_values_
.size());
2142 return this->local_values_
[sym
].output_symtab_index();
2145 // Return the index of local symbol SYM in the dynamic symbol
2146 // table. A value of -1U means that the symbol is not being output.
2148 dynsym_index(unsigned int sym
) const
2150 gold_assert(sym
< this->local_values_
.size());
2151 return this->local_values_
[sym
].output_dynsym_index();
2154 // Return the input section index of local symbol SYM.
2156 local_symbol_input_shndx(unsigned int sym
, bool* is_ordinary
) const
2158 gold_assert(sym
< this->local_values_
.size());
2159 return this->local_values_
[sym
].input_shndx(is_ordinary
);
2162 // Record that local symbol SYM must be in the output symbol table.
2164 set_must_have_output_symtab_entry(unsigned int sym
)
2166 gold_assert(sym
< this->local_values_
.size());
2167 this->local_values_
[sym
].set_must_have_output_symtab_entry();
2170 // Record that local symbol SYM needs a dynamic symbol entry.
2172 set_needs_output_dynsym_entry(unsigned int sym
)
2174 gold_assert(sym
< this->local_values_
.size());
2175 this->local_values_
[sym
].set_needs_output_dynsym_entry();
2178 // Return whether the local symbol SYMNDX has a PLT offset.
2180 local_has_plt_offset(unsigned int symndx
) const;
2182 // Set the PLT offset of the local symbol SYMNDX.
2184 set_local_plt_offset(unsigned int symndx
, unsigned int plt_offset
);
2186 // Adjust this local symbol value. Return false if the symbol
2187 // should be discarded from the output file.
2189 adjust_local_symbol(Symbol_value
<size
>* lv
) const
2190 { return this->do_adjust_local_symbol(lv
); }
2192 // Return the name of the symbol that spans the given offset in the
2193 // specified section in this object. This is used only for error
2194 // messages and is not particularly efficient.
2196 get_symbol_location_info(unsigned int shndx
, off_t offset
,
2197 Symbol_location_info
* info
);
2199 // Look for a kept section corresponding to the given discarded section,
2200 // and return its output address. This is used only for relocations in
2201 // debugging sections.
2203 map_to_kept_section(unsigned int shndx
, bool* found
) const;
2205 // Compute final local symbol value. R_SYM is the local symbol index.
2206 // LV_IN points to a local symbol value containing the input value.
2207 // LV_OUT points to a local symbol value storing the final output value,
2208 // which must not be a merged symbol value since before calling this
2209 // method to avoid memory leak. SYMTAB points to a symbol table.
2211 // The method returns a status code at return. If the return status is
2212 // CFLV_OK, *LV_OUT contains the final value. If the return status is
2213 // CFLV_ERROR, *LV_OUT is 0. If the return status is CFLV_DISCARDED,
2214 // *LV_OUT is not modified.
2215 Compute_final_local_value_status
2216 compute_final_local_value(unsigned int r_sym
,
2217 const Symbol_value
<size
>* lv_in
,
2218 Symbol_value
<size
>* lv_out
,
2219 const Symbol_table
* symtab
);
2221 // Return true if the layout for this object was deferred.
2222 bool is_deferred_layout() const
2223 { return this->is_deferred_layout_
; }
2226 typedef typename Sized_relobj
<size
, big_endian
>::Output_sections
2233 // Read the symbols.
2235 do_read_symbols(Read_symbols_data
*);
2237 // Read the symbols. This is common code for all target-specific
2238 // overrides of do_read_symbols.
2240 base_read_symbols(Read_symbols_data
*);
2242 // Return the value of a local symbol.
2244 do_local_symbol_value(unsigned int symndx
, uint64_t addend
) const
2246 const Symbol_value
<size
>* symval
= this->local_symbol(symndx
);
2247 return symval
->value(this, addend
);
2250 // Return the PLT offset for a local symbol. It is an error to call
2251 // this if it doesn't have one.
2253 do_local_plt_offset(unsigned int symndx
) const;
2255 // Return whether local symbol SYMNDX is a TLS symbol.
2257 do_local_is_tls(unsigned int symndx
) const
2258 { return this->local_symbol(symndx
)->is_tls_symbol(); }
2260 // Return the number of local symbols.
2262 do_local_symbol_count() const
2263 { return this->local_symbol_count_
; }
2265 // Return the number of local symbols in the output symbol table.
2267 do_output_local_symbol_count() const
2268 { return this->output_local_symbol_count_
; }
2270 // Return the number of local symbols in the output symbol table.
2272 do_local_symbol_offset() const
2273 { return this->local_symbol_offset_
; }
2275 // Lay out the input sections.
2277 do_layout(Symbol_table
*, Layout
*, Read_symbols_data
*);
2279 // Layout sections whose layout was deferred while waiting for
2280 // input files from a plugin.
2282 do_layout_deferred_sections(Layout
*);
2284 // Add the symbols to the symbol table.
2286 do_add_symbols(Symbol_table
*, Read_symbols_data
*, Layout
*);
2288 Archive::Should_include
2289 do_should_include_member(Symbol_table
* symtab
, Layout
*, Read_symbols_data
*,
2292 // Iterate over global symbols, calling a visitor class V for each.
2294 do_for_all_global_symbols(Read_symbols_data
* sd
,
2295 Library_base::Symbol_visitor_base
* v
);
2299 do_read_relocs(Read_relocs_data
*);
2301 // Process the relocs to find list of referenced sections. Used only
2302 // during garbage collection.
2304 do_gc_process_relocs(Symbol_table
*, Layout
*, Read_relocs_data
*);
2306 // Scan the relocs and adjust the symbol table.
2308 do_scan_relocs(Symbol_table
*, Layout
*, Read_relocs_data
*);
2310 // Count the local symbols.
2312 do_count_local_symbols(Stringpool_template
<char>*,
2313 Stringpool_template
<char>*);
2315 // Finalize the local symbols.
2317 do_finalize_local_symbols(unsigned int, off_t
, Symbol_table
*);
2319 // Set the offset where local dynamic symbol information will be stored.
2321 do_set_local_dynsym_indexes(unsigned int);
2323 // Set the offset where local dynamic symbol information will be stored.
2325 do_set_local_dynsym_offset(off_t
);
2327 // Relocate the input sections and write out the local symbols.
2329 do_relocate(const Symbol_table
* symtab
, const Layout
*, Output_file
* of
);
2331 // Get the size of a section.
2333 do_section_size(unsigned int shndx
)
2334 { return this->elf_file_
.section_size(shndx
); }
2336 // Get the name of a section.
2338 do_section_name(unsigned int shndx
) const
2339 { return this->elf_file_
.section_name(shndx
); }
2341 // Return the location of the contents of a section.
2342 const unsigned char*
2343 do_section_contents(unsigned int shndx
, section_size_type
* plen
,
2346 Object::Location
loc(this->elf_file_
.section_contents(shndx
));
2347 *plen
= convert_to_section_size_type(loc
.data_size
);
2350 static const unsigned char empty
[1] = { '\0' };
2353 return this->get_view(loc
.file_offset
, *plen
, true, cache
);
2356 // Return section flags.
2358 do_section_flags(unsigned int shndx
);
2360 // Return section entsize.
2362 do_section_entsize(unsigned int shndx
);
2364 // Return section address.
2366 do_section_address(unsigned int shndx
)
2367 { return this->elf_file_
.section_addr(shndx
); }
2369 // Return section type.
2371 do_section_type(unsigned int shndx
)
2372 { return this->elf_file_
.section_type(shndx
); }
2374 // Return the section link field.
2376 do_section_link(unsigned int shndx
)
2377 { return this->elf_file_
.section_link(shndx
); }
2379 // Return the section info field.
2381 do_section_info(unsigned int shndx
)
2382 { return this->elf_file_
.section_info(shndx
); }
2384 // Return the section alignment.
2386 do_section_addralign(unsigned int shndx
)
2387 { return this->elf_file_
.section_addralign(shndx
); }
2389 // Return the Xindex structure to use.
2391 do_initialize_xindex();
2393 // Get symbol counts.
2395 do_get_global_symbol_counts(const Symbol_table
*, size_t*, size_t*) const;
2397 // Get the global symbols.
2399 do_get_global_symbols() const
2400 { return &this->symbols_
; }
2402 // Adjust a section index if necessary.
2404 adjust_shndx(unsigned int shndx
)
2406 if (shndx
>= elfcpp::SHN_LORESERVE
)
2407 shndx
+= this->elf_file_
.large_shndx_offset();
2411 // Initialize input to output maps for section symbols in merged
2414 initialize_input_to_output_maps();
2416 // Free the input to output maps for section symbols in merged
2419 free_input_to_output_maps();
2421 // Return symbol table section index.
2423 symtab_shndx() const
2424 { return this->symtab_shndx_
; }
2426 // Allow a child class to access the ELF file.
2427 elfcpp::Elf_file
<size
, big_endian
, Object
>*
2429 { return &this->elf_file_
; }
2431 // Allow a child class to access the local values.
2434 { return &this->local_values_
; }
2436 // Views and sizes when relocating.
2439 unsigned char* view
;
2440 typename
elfcpp::Elf_types
<size
>::Elf_Addr address
;
2442 section_size_type view_size
;
2443 bool is_input_output_view
;
2444 bool is_postprocessing_view
;
2445 bool is_ctors_reverse_view
;
2448 typedef std::vector
<View_size
> Views
;
2450 // Stash away info for a number of special sections.
2451 // Return true if any of the sections found require local symbols to be read.
2453 do_find_special_sections(Read_symbols_data
* sd
);
2455 // This may be overriden by a child class.
2457 do_relocate_sections(const Symbol_table
* symtab
, const Layout
* layout
,
2458 const unsigned char* pshdrs
, Output_file
* of
,
2461 // Adjust this local symbol value. Return false if the symbol
2462 // should be discarded from the output file.
2464 do_adjust_local_symbol(Symbol_value
<size
>*) const
2467 // Allow a child to set output local symbol count.
2469 set_output_local_symbol_count(unsigned int value
)
2470 { this->output_local_symbol_count_
= value
; }
2474 typedef Sized_relobj_file
<size
, big_endian
> This
;
2475 static const int ehdr_size
= elfcpp::Elf_sizes
<size
>::ehdr_size
;
2476 static const int shdr_size
= elfcpp::Elf_sizes
<size
>::shdr_size
;
2477 static const int sym_size
= elfcpp::Elf_sizes
<size
>::sym_size
;
2478 typedef elfcpp::Shdr
<size
, big_endian
> Shdr
;
2480 // To keep track of discarded comdat sections, we need to map a member
2481 // section index to the object and section index of the corresponding
2483 struct Kept_comdat_section
2485 Kept_comdat_section(Relobj
* a_object
, unsigned int a_shndx
)
2486 : object(a_object
), shndx(a_shndx
)
2491 typedef std::map
<unsigned int, Kept_comdat_section
>
2492 Kept_comdat_section_table
;
2494 // Find the SHT_SYMTAB section, given the section headers.
2496 find_symtab(const unsigned char* pshdrs
);
2498 // Return whether SHDR has the right flags for a GNU style exception
2501 check_eh_frame_flags(const elfcpp::Shdr
<size
, big_endian
>* shdr
) const;
2503 // Return whether there is a section named .eh_frame which might be
2504 // a GNU style exception frame section.
2506 find_eh_frame(const unsigned char* pshdrs
, const char* names
,
2507 section_size_type names_size
) const;
2509 // Whether to include a section group in the link.
2511 include_section_group(Symbol_table
*, Layout
*, unsigned int, const char*,
2512 const unsigned char*, const char*, section_size_type
,
2513 std::vector
<bool>*);
2515 // Whether to include a linkonce section in the link.
2517 include_linkonce_section(Layout
*, unsigned int, const char*,
2518 const elfcpp::Shdr
<size
, big_endian
>&);
2520 // Layout an input section.
2522 layout_section(Layout
* layout
, unsigned int shndx
, const char* name
,
2523 const typename
This::Shdr
& shdr
, unsigned int reloc_shndx
,
2524 unsigned int reloc_type
);
2526 // Layout an input .eh_frame section.
2528 layout_eh_frame_section(Layout
* layout
, const unsigned char* symbols_data
,
2529 section_size_type symbols_size
,
2530 const unsigned char* symbol_names_data
,
2531 section_size_type symbol_names_size
,
2532 unsigned int shndx
, const typename
This::Shdr
&,
2533 unsigned int reloc_shndx
, unsigned int reloc_type
);
2535 // Write section data to the output file. Record the views and
2536 // sizes in VIEWS for use when relocating.
2538 write_sections(const Layout
*, const unsigned char* pshdrs
, Output_file
*,
2541 // Relocate the sections in the output file.
2543 relocate_sections(const Symbol_table
* symtab
, const Layout
* layout
,
2544 const unsigned char* pshdrs
, Output_file
* of
,
2546 { this->do_relocate_sections(symtab
, layout
, pshdrs
, of
, pviews
); }
2548 // Reverse the words in a section. Used for .ctors sections mapped
2549 // to .init_array sections.
2551 reverse_words(unsigned char*, section_size_type
);
2553 // Scan the input relocations for --emit-relocs.
2555 emit_relocs_scan(Symbol_table
*, Layout
*, const unsigned char* plocal_syms
,
2556 const Read_relocs_data::Relocs_list::iterator
&);
2558 // Scan the input relocations for --emit-relocs, templatized on the
2559 // type of the relocation section.
2560 template<int sh_type
>
2562 emit_relocs_scan_reltype(Symbol_table
*, Layout
*,
2563 const unsigned char* plocal_syms
,
2564 const Read_relocs_data::Relocs_list::iterator
&,
2565 Relocatable_relocs
*);
2567 // Scan the input relocations for --incremental.
2569 incremental_relocs_scan(const Read_relocs_data::Relocs_list::iterator
&);
2571 // Scan the input relocations for --incremental, templatized on the
2572 // type of the relocation section.
2573 template<int sh_type
>
2575 incremental_relocs_scan_reltype(
2576 const Read_relocs_data::Relocs_list::iterator
&);
2579 incremental_relocs_write(const Relocate_info
<size
, big_endian
>*,
2580 unsigned int sh_type
,
2581 const unsigned char* prelocs
,
2584 Address output_offset
,
2587 template<int sh_type
>
2589 incremental_relocs_write_reltype(const Relocate_info
<size
, big_endian
>*,
2590 const unsigned char* prelocs
,
2593 Address output_offset
,
2596 // A type shared by split_stack_adjust_reltype and find_functions.
2597 typedef std::map
<section_offset_type
, section_size_type
> Function_offsets
;
2599 // Check for -fsplit-stack routines calling non-split-stack routines.
2601 split_stack_adjust(const Symbol_table
*, const unsigned char* pshdrs
,
2602 unsigned int sh_type
, unsigned int shndx
,
2603 const unsigned char* prelocs
, size_t reloc_count
,
2604 unsigned char* view
, section_size_type view_size
,
2605 Reloc_symbol_changes
** reloc_map
);
2607 template<int sh_type
>
2609 split_stack_adjust_reltype(const Symbol_table
*, const unsigned char* pshdrs
,
2610 unsigned int shndx
, const unsigned char* prelocs
,
2611 size_t reloc_count
, unsigned char* view
,
2612 section_size_type view_size
,
2613 Reloc_symbol_changes
** reloc_map
);
2615 // Find all functions in a section.
2617 find_functions(const unsigned char* pshdrs
, unsigned int shndx
,
2620 // Write out the local symbols.
2622 write_local_symbols(Output_file
*,
2623 const Stringpool_template
<char>*,
2624 const Stringpool_template
<char>*,
2625 Output_symtab_xindex
*,
2626 Output_symtab_xindex
*,
2629 // Record a mapping from discarded section SHNDX to the corresponding
2632 set_kept_comdat_section(unsigned int shndx
, Relobj
* kept_object
,
2633 unsigned int kept_shndx
)
2635 Kept_comdat_section
kept(kept_object
, kept_shndx
);
2636 this->kept_comdat_sections_
.insert(std::make_pair(shndx
, kept
));
2639 // Find the kept section corresponding to the discarded section
2640 // SHNDX. Return true if found.
2642 get_kept_comdat_section(unsigned int shndx
, Relobj
** kept_object
,
2643 unsigned int* kept_shndx
) const
2645 typename
Kept_comdat_section_table::const_iterator p
=
2646 this->kept_comdat_sections_
.find(shndx
);
2647 if (p
== this->kept_comdat_sections_
.end())
2649 *kept_object
= p
->second
.object
;
2650 *kept_shndx
= p
->second
.shndx
;
2654 // Compute final local symbol value. R_SYM is the local symbol index.
2655 // LV_IN points to a local symbol value containing the input value.
2656 // LV_OUT points to a local symbol value storing the final output value,
2657 // which must not be a merged symbol value since before calling this
2658 // method to avoid memory leak. RELOCATABLE indicates whether we are
2659 // linking a relocatable output. OUT_SECTIONS is an array of output
2660 // sections. OUT_OFFSETS is an array of offsets of the sections. SYMTAB
2661 // points to a symbol table.
2663 // The method returns a status code at return. If the return status is
2664 // CFLV_OK, *LV_OUT contains the final value. If the return status is
2665 // CFLV_ERROR, *LV_OUT is 0. If the return status is CFLV_DISCARDED,
2666 // *LV_OUT is not modified.
2667 inline Compute_final_local_value_status
2668 compute_final_local_value_internal(unsigned int r_sym
,
2669 const Symbol_value
<size
>* lv_in
,
2670 Symbol_value
<size
>* lv_out
,
2672 const Output_sections
& out_sections
,
2673 const std::vector
<Address
>& out_offsets
,
2674 const Symbol_table
* symtab
);
2676 // The PLT offsets of local symbols.
2677 typedef Unordered_map
<unsigned int, unsigned int> Local_plt_offsets
;
2679 // Saved information for sections whose layout was deferred.
2680 struct Deferred_layout
2682 static const int shdr_size
= elfcpp::Elf_sizes
<size
>::shdr_size
;
2683 Deferred_layout(unsigned int shndx
, const char* name
,
2684 const unsigned char* pshdr
,
2685 unsigned int reloc_shndx
, unsigned int reloc_type
)
2686 : shndx_(shndx
), name_(name
), reloc_shndx_(reloc_shndx
),
2687 reloc_type_(reloc_type
)
2689 memcpy(this->shdr_data_
, pshdr
, shdr_size
);
2691 unsigned int shndx_
;
2693 unsigned int reloc_shndx_
;
2694 unsigned int reloc_type_
;
2695 unsigned char shdr_data_
[shdr_size
];
2698 // General access to the ELF file.
2699 elfcpp::Elf_file
<size
, big_endian
, Object
> elf_file_
;
2700 // Type of ELF file (ET_REL or ET_EXEC). ET_EXEC files are allowed
2701 // as input files only for the --just-symbols option.
2703 // Index of SHT_SYMTAB section.
2704 unsigned int symtab_shndx_
;
2705 // The number of local symbols.
2706 unsigned int local_symbol_count_
;
2707 // The number of local symbols which go into the output file.
2708 unsigned int output_local_symbol_count_
;
2709 // The number of local symbols which go into the output file's dynamic
2711 unsigned int output_local_dynsym_count_
;
2712 // The entries in the symbol table for the external symbols.
2714 // Number of symbols defined in object file itself.
2715 size_t defined_count_
;
2716 // File offset for local symbols (relative to start of symbol table).
2717 off_t local_symbol_offset_
;
2718 // File offset for local dynamic symbols (absolute).
2719 off_t local_dynsym_offset_
;
2720 // Values of local symbols.
2721 Local_values local_values_
;
2722 // PLT offsets for local symbols.
2723 Local_plt_offsets local_plt_offsets_
;
2724 // Table mapping discarded comdat sections to corresponding kept sections.
2725 Kept_comdat_section_table kept_comdat_sections_
;
2726 // Whether this object has a GNU style .eh_frame section.
2728 // If this object has a GNU style .eh_frame section that is discarded in
2729 // output, record the index here. Otherwise it is -1U.
2730 unsigned int discarded_eh_frame_shndx_
;
2731 // True if the layout of this object was deferred, waiting for plugin
2732 // replacement files.
2733 bool is_deferred_layout_
;
2734 // The list of sections whose layout was deferred.
2735 std::vector
<Deferred_layout
> deferred_layout_
;
2736 // The list of relocation sections whose layout was deferred.
2737 std::vector
<Deferred_layout
> deferred_layout_relocs_
;
2740 // A class to manage the list of all objects.
2746 : relobj_list_(), dynobj_list_(), sonames_(), cref_(NULL
)
2749 // The type of the list of input relocateable objects.
2750 typedef std::vector
<Relobj
*> Relobj_list
;
2751 typedef Relobj_list::const_iterator Relobj_iterator
;
2753 // The type of the list of input dynamic objects.
2754 typedef std::vector
<Dynobj
*> Dynobj_list
;
2755 typedef Dynobj_list::const_iterator Dynobj_iterator
;
2757 // Add an object to the list. Return true if all is well, or false
2758 // if this object should be ignored.
2760 add_object(Object
*);
2762 // Start processing an archive.
2764 archive_start(Archive
*);
2766 // Stop processing an archive.
2768 archive_stop(Archive
*);
2770 // For each dynamic object, check whether we've seen all of its
2771 // explicit dependencies.
2773 check_dynamic_dependencies() const;
2775 // Return whether an object was found in the system library
2778 found_in_system_library_directory(const Object
*) const;
2780 // Print symbol counts.
2782 print_symbol_counts(const Symbol_table
*) const;
2784 // Print a cross reference table.
2786 print_cref(const Symbol_table
*, FILE*) const;
2788 // Iterate over all regular objects.
2791 relobj_begin() const
2792 { return this->relobj_list_
.begin(); }
2796 { return this->relobj_list_
.end(); }
2798 // Iterate over all dynamic objects.
2801 dynobj_begin() const
2802 { return this->dynobj_list_
.begin(); }
2806 { return this->dynobj_list_
.end(); }
2808 // Return whether we have seen any dynamic objects.
2811 { return !this->dynobj_list_
.empty(); }
2813 // Return the number of non dynamic objects.
2815 number_of_relobjs() const
2816 { return this->relobj_list_
.size(); }
2818 // Return the number of input objects.
2820 number_of_input_objects() const
2821 { return this->relobj_list_
.size() + this->dynobj_list_
.size(); }
2824 Input_objects(const Input_objects
&);
2825 Input_objects
& operator=(const Input_objects
&);
2827 // The list of ordinary objects included in the link.
2828 Relobj_list relobj_list_
;
2829 // The list of dynamic objects included in the link.
2830 Dynobj_list dynobj_list_
;
2831 // SONAMEs that we have seen.
2832 Unordered_set
<std::string
> sonames_
;
2833 // Manage cross-references if requested.
2837 // Some of the information we pass to the relocation routines. We
2838 // group this together to avoid passing a dozen different arguments.
2840 template<int size
, bool big_endian
>
2841 struct Relocate_info
2844 const Symbol_table
* symtab
;
2846 const Layout
* layout
;
2847 // Object being relocated.
2848 Sized_relobj_file
<size
, big_endian
>* object
;
2849 // Section index of relocation section.
2850 unsigned int reloc_shndx
;
2851 // Section header of relocation section.
2852 const unsigned char* reloc_shdr
;
2853 // Section index of section being relocated.
2854 unsigned int data_shndx
;
2855 // Section header of data section.
2856 const unsigned char* data_shdr
;
2858 // Return a string showing the location of a relocation. This is
2859 // only used for error messages.
2861 location(size_t relnum
, off_t reloffset
) const;
2864 // This is used to represent a section in an object and is used as the
2865 // key type for various section maps.
2866 typedef std::pair
<Relobj
*, unsigned int> Section_id
;
2868 // This is similar to Section_id but is used when the section
2869 // pointers are const.
2870 typedef std::pair
<const Relobj
*, unsigned int> Const_section_id
;
2872 // The hash value is based on the address of an object in memory during
2873 // linking. It is okay to use this for looking up sections but never use
2874 // this in an unordered container that we want to traverse in a repeatable
2877 struct Section_id_hash
2879 size_t operator()(const Section_id
& loc
) const
2880 { return reinterpret_cast<uintptr_t>(loc
.first
) ^ loc
.second
; }
2883 struct Const_section_id_hash
2885 size_t operator()(const Const_section_id
& loc
) const
2886 { return reinterpret_cast<uintptr_t>(loc
.first
) ^ loc
.second
; }
2889 // Return whether INPUT_FILE contains an ELF object start at file
2890 // offset OFFSET. This sets *START to point to a view of the start of
2891 // the file. It sets *READ_SIZE to the number of bytes in the view.
2894 is_elf_object(Input_file
* input_file
, off_t offset
,
2895 const unsigned char** start
, int* read_size
);
2897 // Return an Object appropriate for the input file. P is BYTES long,
2898 // and holds the ELF header. If PUNCONFIGURED is not NULL, then if
2899 // this sees an object the linker is not configured to support, it
2900 // sets *PUNCONFIGURED to true and returns NULL without giving an
2904 make_elf_object(const std::string
& name
, Input_file
*,
2905 off_t offset
, const unsigned char* p
,
2906 section_offset_type bytes
, bool* punconfigured
);
2908 } // end namespace gold
2910 #endif // !defined(GOLD_OBJECT_H)