1 // object.h -- support for an object file for linking in gold -*- C++ -*-
3 // Copyright (C) 2006-2014 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
;
45 class Output_symtab_xindex
;
48 class Object_merge_map
;
49 class Relocatable_relocs
;
52 template<typename Stringpool_char
>
53 class Stringpool_template
;
55 // Data to pass from read_symbols() to add_symbols().
57 struct Read_symbols_data
60 : section_headers(NULL
), section_names(NULL
), symbols(NULL
),
61 symbol_names(NULL
), versym(NULL
), verdef(NULL
), verneed(NULL
)
67 File_view
* section_headers
;
69 File_view
* section_names
;
70 // Size of section name data in bytes.
71 section_size_type section_names_size
;
74 // Size of symbol data in bytes.
75 section_size_type symbols_size
;
76 // Offset of external symbols within symbol data. This structure
77 // sometimes contains only external symbols, in which case this will
78 // be zero. Sometimes it contains all symbols.
79 section_offset_type external_symbols_offset
;
81 File_view
* symbol_names
;
82 // Size of symbol name data in bytes.
83 section_size_type symbol_names_size
;
85 // Version information. This is only used on dynamic objects.
86 // Version symbol data (from SHT_GNU_versym section).
88 section_size_type versym_size
;
89 // Version definition data (from SHT_GNU_verdef section).
91 section_size_type verdef_size
;
92 unsigned int verdef_info
;
93 // Needed version data (from SHT_GNU_verneed section).
95 section_size_type verneed_size
;
96 unsigned int verneed_info
;
99 // Information used to print error messages.
101 struct Symbol_location_info
103 std::string source_file
;
104 std::string enclosing_symbol_name
;
105 elfcpp::STT enclosing_symbol_type
;
108 // Data about a single relocation section. This is read in
109 // read_relocs and processed in scan_relocs.
111 struct Section_relocs
118 { delete this->contents
; }
120 // Index of reloc section.
121 unsigned int reloc_shndx
;
122 // Index of section that relocs apply to.
123 unsigned int data_shndx
;
124 // Contents of reloc section.
126 // Reloc section type.
127 unsigned int sh_type
;
128 // Number of reloc entries.
131 Output_section
* output_section
;
132 // Whether this section has special handling for offsets.
133 bool needs_special_offset_handling
;
134 // Whether the data section is allocated (has the SHF_ALLOC flag set).
135 bool is_data_section_allocated
;
138 // Relocations in an object file. This is read in read_relocs and
139 // processed in scan_relocs.
141 struct Read_relocs_data
144 : local_symbols(NULL
)
148 { delete this->local_symbols
; }
150 typedef std::vector
<Section_relocs
> Relocs_list
;
153 // The local symbols.
154 File_view
* local_symbols
;
157 // The Xindex class manages section indexes for objects with more than
163 Xindex(int large_shndx_offset
)
164 : large_shndx_offset_(large_shndx_offset
), symtab_xindex_()
167 // Initialize the symtab_xindex_ array, given the object and the
168 // section index of the symbol table to use.
169 template<int size
, bool big_endian
>
171 initialize_symtab_xindex(Object
*, unsigned int symtab_shndx
);
173 // Read in the symtab_xindex_ array, given its section index.
174 // PSHDRS may optionally point to the section headers.
175 template<int size
, bool big_endian
>
177 read_symtab_xindex(Object
*, unsigned int xindex_shndx
,
178 const unsigned char* pshdrs
);
180 // Symbol SYMNDX in OBJECT has a section of SHN_XINDEX; return the
181 // real section index.
183 sym_xindex_to_shndx(Object
* object
, unsigned int symndx
);
186 // The type of the array giving the real section index for symbols
187 // whose st_shndx field holds SHN_XINDEX.
188 typedef std::vector
<unsigned int> Symtab_xindex
;
190 // Adjust a section index if necessary. This should only be called
191 // for ordinary section indexes.
193 adjust_shndx(unsigned int shndx
)
195 if (shndx
>= elfcpp::SHN_LORESERVE
)
196 shndx
+= this->large_shndx_offset_
;
200 // Adjust to apply to large section indexes.
201 int large_shndx_offset_
;
202 // The data from the SHT_SYMTAB_SHNDX section.
203 Symtab_xindex symtab_xindex_
;
206 // A GOT offset list. A symbol may have more than one GOT offset
207 // (e.g., when mixing modules compiled with two different TLS models),
208 // but will usually have at most one. GOT_TYPE identifies the type of
209 // GOT entry; its values are specific to each target.
211 class Got_offset_list
215 : got_type_(-1U), got_offset_(0), got_next_(NULL
)
218 Got_offset_list(unsigned int got_type
, unsigned int got_offset
)
219 : got_type_(got_type
), got_offset_(got_offset
), got_next_(NULL
)
224 if (this->got_next_
!= NULL
)
226 delete this->got_next_
;
227 this->got_next_
= NULL
;
231 // Initialize the fields to their default values.
235 this->got_type_
= -1U;
236 this->got_offset_
= 0;
237 this->got_next_
= NULL
;
240 // Set the offset for the GOT entry of type GOT_TYPE.
242 set_offset(unsigned int got_type
, unsigned int got_offset
)
244 if (this->got_type_
== -1U)
246 this->got_type_
= got_type
;
247 this->got_offset_
= got_offset
;
251 for (Got_offset_list
* g
= this; g
!= NULL
; g
= g
->got_next_
)
253 if (g
->got_type_
== got_type
)
255 g
->got_offset_
= got_offset
;
259 Got_offset_list
* g
= new Got_offset_list(got_type
, got_offset
);
260 g
->got_next_
= this->got_next_
;
265 // Return the offset for a GOT entry of type GOT_TYPE.
267 get_offset(unsigned int got_type
) const
269 for (const Got_offset_list
* g
= this; g
!= NULL
; g
= g
->got_next_
)
271 if (g
->got_type_
== got_type
)
272 return g
->got_offset_
;
277 // Return a pointer to the list, or NULL if the list is empty.
278 const Got_offset_list
*
281 if (this->got_type_
== -1U)
286 // Abstract visitor class for iterating over GOT offsets.
298 visit(unsigned int, unsigned int) = 0;
301 // Loop over all GOT offset entries, calling a visitor class V for each.
303 for_all_got_offsets(Visitor
* v
) const
305 if (this->got_type_
== -1U)
307 for (const Got_offset_list
* g
= this; g
!= NULL
; g
= g
->got_next_
)
308 v
->visit(g
->got_type_
, g
->got_offset_
);
312 unsigned int got_type_
;
313 unsigned int got_offset_
;
314 Got_offset_list
* got_next_
;
317 // Object is an abstract base class which represents either a 32-bit
318 // or a 64-bit input object. This can be a regular object file
319 // (ET_REL) or a shared object (ET_DYN).
324 typedef std::vector
<Symbol
*> Symbols
;
326 // NAME is the name of the object as we would report it to the user
327 // (e.g., libfoo.a(bar.o) if this is in an archive. INPUT_FILE is
328 // used to read the file. OFFSET is the offset within the input
329 // file--0 for a .o or .so file, something else for a .a file.
330 Object(const std::string
& name
, Input_file
* input_file
, bool is_dynamic
,
332 : name_(name
), input_file_(input_file
), offset_(offset
), shnum_(-1U),
333 is_dynamic_(is_dynamic
), is_needed_(false), uses_split_stack_(false),
334 has_no_split_stack_(false), no_export_(false),
335 is_in_system_directory_(false), as_needed_(false), xindex_(NULL
)
337 if (input_file
!= NULL
)
339 input_file
->file().add_object();
340 this->is_in_system_directory_
= input_file
->is_in_system_directory();
341 this->as_needed_
= input_file
->options().as_needed();
347 if (this->input_file_
!= NULL
)
348 this->input_file_
->file().remove_object();
351 // Return the name of the object as we would report it to the user.
354 { return this->name_
; }
356 // Get the offset into the file.
359 { return this->offset_
; }
361 // Return whether this is a dynamic object.
364 { return this->is_dynamic_
; }
366 // Return whether this object is needed--true if it is a dynamic
367 // object which defines some symbol referenced by a regular object.
368 // We keep the flag here rather than in Dynobj for convenience when
372 { return this->is_needed_
; }
374 // Record that this object is needed.
377 { this->is_needed_
= true; }
379 // Return whether this object was compiled with -fsplit-stack.
381 uses_split_stack() const
382 { return this->uses_split_stack_
; }
384 // Return whether this object contains any functions compiled with
385 // the no_split_stack attribute.
387 has_no_split_stack() const
388 { return this->has_no_split_stack_
; }
390 // Returns NULL for Objects that are not dynamic objects. This method
391 // is overridden in the Dynobj class.
394 { return this->do_dynobj(); }
396 // Returns NULL for Objects that are not plugin objects. This method
397 // is overridden in the Pluginobj class.
400 { return this->do_pluginobj(); }
402 // Get the file. We pass on const-ness.
406 gold_assert(this->input_file_
!= NULL
);
407 return this->input_file_
;
413 gold_assert(this->input_file_
!= NULL
);
414 return this->input_file_
;
417 // Lock the underlying file.
421 if (this->input_file_
!= NULL
)
422 this->input_file_
->file().lock(t
);
425 // Unlock the underlying file.
427 unlock(const Task
* t
)
429 if (this->input_file_
!= NULL
)
430 this->input_file()->file().unlock(t
);
433 // Return whether the underlying file is locked.
436 { return this->input_file_
!= NULL
&& this->input_file_
->file().is_locked(); }
438 // Return the token, so that the task can be queued.
442 if (this->input_file_
== NULL
)
444 return this->input_file()->file().token();
447 // Release the underlying file.
451 if (this->input_file_
!= NULL
)
452 this->input_file()->file().release();
455 // Return whether we should just read symbols from this file.
458 { return this->input_file()->just_symbols(); }
460 // Return whether this is an incremental object.
462 is_incremental() const
463 { return this->do_is_incremental(); }
465 // Return the last modified time of the file.
468 { return this->do_get_mtime(); }
470 // Get the number of sections.
473 { return this->shnum_
; }
475 // Return a view of the contents of a section. Set *PLEN to the
476 // size. CACHE is a hint as in File_read::get_view.
478 section_contents(unsigned int shndx
, section_size_type
* plen
, bool cache
);
480 // Adjust a symbol's section index as needed. SYMNDX is the index
481 // of the symbol and SHNDX is the symbol's section from
482 // get_st_shndx. This returns the section index. It sets
483 // *IS_ORDINARY to indicate whether this is a normal section index,
484 // rather than a special code between SHN_LORESERVE and
487 adjust_sym_shndx(unsigned int symndx
, unsigned int shndx
, bool* is_ordinary
)
489 if (shndx
< elfcpp::SHN_LORESERVE
)
491 else if (shndx
== elfcpp::SHN_XINDEX
)
493 if (this->xindex_
== NULL
)
494 this->xindex_
= this->do_initialize_xindex();
495 shndx
= this->xindex_
->sym_xindex_to_shndx(this, symndx
);
499 *is_ordinary
= false;
503 // Return the size of a section given a section index.
505 section_size(unsigned int shndx
)
506 { return this->do_section_size(shndx
); }
508 // Return the name of a section given a section index.
510 section_name(unsigned int shndx
)
511 { return this->do_section_name(shndx
); }
513 // Return the section flags given a section index.
515 section_flags(unsigned int shndx
)
516 { return this->do_section_flags(shndx
); }
518 // Return the section entsize given a section index.
520 section_entsize(unsigned int shndx
)
521 { return this->do_section_entsize(shndx
); }
523 // Return the section address given a section index.
525 section_address(unsigned int shndx
)
526 { return this->do_section_address(shndx
); }
528 // Return the section type given a section index.
530 section_type(unsigned int shndx
)
531 { return this->do_section_type(shndx
); }
533 // Return the section link field given a section index.
535 section_link(unsigned int shndx
)
536 { return this->do_section_link(shndx
); }
538 // Return the section info field given a section index.
540 section_info(unsigned int shndx
)
541 { return this->do_section_info(shndx
); }
543 // Return the required section alignment given a section index.
545 section_addralign(unsigned int shndx
)
546 { return this->do_section_addralign(shndx
); }
548 // Return the output section given a section index.
550 output_section(unsigned int shndx
) const
551 { return this->do_output_section(shndx
); }
553 // Given a section index, return its address.
554 // The return value will be -1U if the section is specially mapped,
555 // such as a merge section.
557 output_section_address(unsigned int shndx
)
558 { return this->do_output_section_address(shndx
); }
560 // Given a section index, return the offset in the Output_section.
561 // The return value will be -1U if the section is specially mapped,
562 // such as a merge section.
564 output_section_offset(unsigned int shndx
) const
565 { return this->do_output_section_offset(shndx
); }
567 // Read the symbol information.
569 read_symbols(Read_symbols_data
* sd
)
570 { return this->do_read_symbols(sd
); }
572 // Pass sections which should be included in the link to the Layout
573 // object, and record where the sections go in the output file.
575 layout(Symbol_table
* symtab
, Layout
* layout
, Read_symbols_data
* sd
)
576 { this->do_layout(symtab
, layout
, sd
); }
578 // Add symbol information to the global symbol table.
580 add_symbols(Symbol_table
* symtab
, Read_symbols_data
* sd
, Layout
*layout
)
581 { this->do_add_symbols(symtab
, sd
, layout
); }
583 // Add symbol information to the global symbol table.
584 Archive::Should_include
585 should_include_member(Symbol_table
* symtab
, Layout
* layout
,
586 Read_symbols_data
* sd
, std::string
* why
)
587 { return this->do_should_include_member(symtab
, layout
, sd
, why
); }
589 // Iterate over global symbols, calling a visitor class V for each.
591 for_all_global_symbols(Read_symbols_data
* sd
,
592 Library_base::Symbol_visitor_base
* v
)
593 { return this->do_for_all_global_symbols(sd
, v
); }
595 // Iterate over local symbols, calling a visitor class V for each GOT offset
596 // associated with a local symbol.
598 for_all_local_got_entries(Got_offset_list::Visitor
* v
) const
599 { this->do_for_all_local_got_entries(v
); }
601 // Functions and types for the elfcpp::Elf_file interface. This
602 // permit us to use Object as the File template parameter for
605 // The View class is returned by view. It must support a single
606 // method, data(). This is trivial, because get_view does what we
611 View(const unsigned char* p
)
620 const unsigned char* p_
;
625 view(off_t file_offset
, section_size_type data_size
)
626 { return View(this->get_view(file_offset
, data_size
, true, true)); }
630 error(const char* format
, ...) const ATTRIBUTE_PRINTF_2
;
632 // A location in the file.
638 Location(off_t fo
, section_size_type ds
)
639 : file_offset(fo
), data_size(ds
)
643 // Get a View given a Location.
644 View
view(Location loc
)
645 { return View(this->get_view(loc
.file_offset
, loc
.data_size
, true, true)); }
647 // Get a view into the underlying file.
649 get_view(off_t start
, section_size_type size
, bool aligned
, bool cache
)
651 return this->input_file()->file().get_view(this->offset_
, start
, size
,
655 // Get a lasting view into the underlying file.
657 get_lasting_view(off_t start
, section_size_type size
, bool aligned
,
660 return this->input_file()->file().get_lasting_view(this->offset_
, start
,
661 size
, aligned
, cache
);
664 // Read data from the underlying file.
666 read(off_t start
, section_size_type size
, void* p
)
667 { this->input_file()->file().read(start
+ this->offset_
, size
, p
); }
669 // Read multiple data from the underlying file.
671 read_multiple(const File_read::Read_multiple
& rm
)
672 { this->input_file()->file().read_multiple(this->offset_
, rm
); }
674 // Stop caching views in the underlying file.
676 clear_view_cache_marks()
678 if (this->input_file_
!= NULL
)
679 this->input_file_
->file().clear_view_cache_marks();
682 // Get the number of global symbols defined by this object, and the
683 // number of the symbols whose final definition came from this
686 get_global_symbol_counts(const Symbol_table
* symtab
, size_t* defined
,
688 { this->do_get_global_symbol_counts(symtab
, defined
, used
); }
690 // Get the symbols defined in this object.
692 get_global_symbols() const
693 { return this->do_get_global_symbols(); }
695 // Set flag that this object was found in a system directory.
697 set_is_in_system_directory()
698 { this->is_in_system_directory_
= true; }
700 // Return whether this object was found in a system directory.
702 is_in_system_directory() const
703 { return this->is_in_system_directory_
; }
705 // Set flag that this object was linked with --as-needed.
708 { this->as_needed_
= true; }
710 // Return whether this object was linked with --as-needed.
713 { return this->as_needed_
; }
715 // Return whether we found this object by searching a directory.
718 { return this->input_file()->will_search_for(); }
722 { return this->no_export_
; }
725 set_no_export(bool value
)
726 { this->no_export_
= value
; }
728 // Return TRUE if the section is a compressed debug section, and set
729 // *UNCOMPRESSED_SIZE to the size of the uncompressed data.
731 section_is_compressed(unsigned int shndx
,
732 section_size_type
* uncompressed_size
) const
733 { return this->do_section_is_compressed(shndx
, uncompressed_size
); }
735 // Return a view of the decompressed contents of a section. Set *PLEN
736 // to the size. Set *IS_NEW to true if the contents need to be freed
739 decompressed_section_contents(unsigned int shndx
, section_size_type
* plen
,
741 { return this->do_decompressed_section_contents(shndx
, plen
, is_cached
); }
743 // Discard any buffers of decompressed sections. This is done
744 // at the end of the Add_symbols task.
746 discard_decompressed_sections()
747 { this->do_discard_decompressed_sections(); }
749 // Return the index of the first incremental relocation for symbol SYMNDX.
751 get_incremental_reloc_base(unsigned int symndx
) const
752 { return this->do_get_incremental_reloc_base(symndx
); }
754 // Return the number of incremental relocations for symbol SYMNDX.
756 get_incremental_reloc_count(unsigned int symndx
) const
757 { return this->do_get_incremental_reloc_count(symndx
); }
760 // Returns NULL for Objects that are not dynamic objects. This method
761 // is overridden in the Dynobj class.
766 // Returns NULL for Objects that are not plugin objects. This method
767 // is overridden in the Pluginobj class.
772 // Return TRUE if this is an incremental (unchanged) input file.
773 // We return FALSE by default; the incremental object classes
774 // override this method.
776 do_is_incremental() const
779 // Return the last modified time of the file. This method may be
780 // overridden for subclasses that don't use an actual file (e.g.,
781 // Incremental objects).
784 { return this->input_file()->file().get_mtime(); }
786 // Read the symbols--implemented by child class.
788 do_read_symbols(Read_symbols_data
*) = 0;
790 // Lay out sections--implemented by child class.
792 do_layout(Symbol_table
*, Layout
*, Read_symbols_data
*) = 0;
794 // Add symbol information to the global symbol table--implemented by
797 do_add_symbols(Symbol_table
*, Read_symbols_data
*, Layout
*) = 0;
799 virtual Archive::Should_include
800 do_should_include_member(Symbol_table
* symtab
, Layout
*, Read_symbols_data
*,
801 std::string
* why
) = 0;
803 // Iterate over global symbols, calling a visitor class V for each.
805 do_for_all_global_symbols(Read_symbols_data
* sd
,
806 Library_base::Symbol_visitor_base
* v
) = 0;
808 // Iterate over local symbols, calling a visitor class V for each GOT offset
809 // associated with a local symbol.
811 do_for_all_local_got_entries(Got_offset_list::Visitor
* v
) const = 0;
813 // Return the location of the contents of a section. Implemented by
815 virtual const unsigned char*
816 do_section_contents(unsigned int shndx
, section_size_type
* plen
,
819 // Get the size of a section--implemented by child class.
821 do_section_size(unsigned int shndx
) = 0;
823 // Get the name of a section--implemented by child class.
825 do_section_name(unsigned int shndx
) = 0;
827 // Get section flags--implemented by child class.
829 do_section_flags(unsigned int shndx
) = 0;
831 // Get section entsize--implemented by child class.
833 do_section_entsize(unsigned int shndx
) = 0;
835 // Get section address--implemented by child class.
837 do_section_address(unsigned int shndx
) = 0;
839 // Get section type--implemented by child class.
841 do_section_type(unsigned int shndx
) = 0;
843 // Get section link field--implemented by child class.
845 do_section_link(unsigned int shndx
) = 0;
847 // Get section info field--implemented by child class.
849 do_section_info(unsigned int shndx
) = 0;
851 // Get section alignment--implemented by child class.
853 do_section_addralign(unsigned int shndx
) = 0;
855 // Return the output section given a section index--implemented
857 virtual Output_section
*
858 do_output_section(unsigned int) const
859 { gold_unreachable(); }
861 // Get the address of a section--implemented by child class.
863 do_output_section_address(unsigned int)
864 { gold_unreachable(); }
866 // Get the offset of a section--implemented by child class.
868 do_output_section_offset(unsigned int) const
869 { gold_unreachable(); }
871 // Return the Xindex structure to use.
873 do_initialize_xindex() = 0;
875 // Implement get_global_symbol_counts--implemented by child class.
877 do_get_global_symbol_counts(const Symbol_table
*, size_t*, size_t*) const = 0;
879 virtual const Symbols
*
880 do_get_global_symbols() const = 0;
882 // Set the number of sections.
885 { this->shnum_
= shnum
; }
887 // Functions used by both Sized_relobj_file and Sized_dynobj.
889 // Read the section data into a Read_symbols_data object.
890 template<int size
, bool big_endian
>
892 read_section_data(elfcpp::Elf_file
<size
, big_endian
, Object
>*,
895 // Find the section header with the given NAME. If HDR is non-NULL
896 // then it is a section header returned from a previous call to this
897 // function and the next section header with the same name will be
899 template<int size
, bool big_endian
>
901 find_shdr(const unsigned char* pshdrs
, const char* name
,
902 const char* names
, section_size_type names_size
,
903 const unsigned char* hdr
) const;
905 // Let the child class initialize the xindex object directly.
907 set_xindex(Xindex
* xindex
)
909 gold_assert(this->xindex_
== NULL
);
910 this->xindex_
= xindex
;
913 // If NAME is the name of a special .gnu.warning section, arrange
914 // for the warning to be issued. SHNDX is the section index.
915 // Return whether it is a warning section.
917 handle_gnu_warning_section(const char* name
, unsigned int shndx
,
920 // If NAME is the name of the special section which indicates that
921 // this object was compiled with -fsplit-stack, mark it accordingly,
922 // and return true. Otherwise return false.
924 handle_split_stack_section(const char* name
);
926 // Return TRUE if the section is a compressed debug section, and set
927 // *UNCOMPRESSED_SIZE to the size of the uncompressed data.
929 do_section_is_compressed(unsigned int, section_size_type
*) const
932 // Return a view of the decompressed contents of a section. Set *PLEN
933 // to the size. This default implementation simply returns the
934 // raw section contents and sets *IS_NEW to false to indicate
935 // that the contents do not need to be freed by the caller.
936 // This function must be overridden for any types of object files
937 // that might contain compressed sections.
938 virtual const unsigned char*
939 do_decompressed_section_contents(unsigned int shndx
,
940 section_size_type
* plen
,
944 return this->do_section_contents(shndx
, plen
, false);
947 // Discard any buffers of decompressed sections. This is done
948 // at the end of the Add_symbols task.
950 do_discard_decompressed_sections()
953 // Return the index of the first incremental relocation for symbol SYMNDX--
954 // implemented by child class.
956 do_get_incremental_reloc_base(unsigned int) const
957 { gold_unreachable(); }
959 // Return the number of incremental relocations for symbol SYMNDX--
960 // implemented by child class.
962 do_get_incremental_reloc_count(unsigned int) const
963 { gold_unreachable(); }
966 // This class may not be copied.
967 Object(const Object
&);
968 Object
& operator=(const Object
&);
970 // Name of object as printed to user.
972 // For reading the file.
973 Input_file
* input_file_
;
974 // Offset within the file--0 for an object file, non-0 for an
977 // Number of input sections.
979 // Whether this is a dynamic object.
980 bool is_dynamic_
: 1;
981 // Whether this object is needed. This is only set for dynamic
982 // objects, and means that the object defined a symbol which was
983 // used by a reference from a regular object.
985 // Whether this object was compiled with -fsplit-stack.
986 bool uses_split_stack_
: 1;
987 // Whether this object contains any functions compiled with the
988 // no_split_stack attribute.
989 bool has_no_split_stack_
: 1;
990 // True if exclude this object from automatic symbol export.
991 // This is used only for archive objects.
993 // True if the object was found in a system directory.
994 bool is_in_system_directory_
: 1;
995 // True if the object was linked with --as-needed.
997 // Many sections for objects with more than SHN_LORESERVE sections.
1001 // A regular object (ET_REL). This is an abstract base class itself.
1002 // The implementation is the template class Sized_relobj_file.
1004 class Relobj
: public Object
1007 Relobj(const std::string
& name
, Input_file
* input_file
, off_t offset
= 0)
1008 : Object(name
, input_file
, false, offset
),
1010 map_to_relocatable_relocs_(NULL
),
1011 object_merge_map_(NULL
),
1012 relocs_must_follow_section_writes_(false),
1014 reloc_counts_(NULL
),
1016 first_dyn_reloc_(0),
1020 // During garbage collection, the Read_symbols_data pass for
1021 // each object is stored as layout needs to be done after
1022 // reloc processing.
1025 { return this->sd_
; }
1027 // Decides which section names have to be included in the worklist
1030 is_section_name_included(const char* name
);
1033 copy_symbols_data(Symbols_data
* gc_sd
, Read_symbols_data
* sd
,
1034 unsigned int section_header_size
);
1037 set_symbols_data(Symbols_data
* sd
)
1040 // During garbage collection, the Read_relocs pass for all objects
1041 // is done before scanning the relocs. In that case, this->rd_ is
1042 // used to store the information from Read_relocs for each object.
1043 // This data is also used to compute the list of relevant sections.
1046 { return this->rd_
; }
1049 set_relocs_data(Read_relocs_data
* rd
)
1053 is_output_section_offset_invalid(unsigned int shndx
) const = 0;
1057 read_relocs(Read_relocs_data
* rd
)
1058 { return this->do_read_relocs(rd
); }
1060 // Process the relocs, during garbage collection only.
1062 gc_process_relocs(Symbol_table
* symtab
, Layout
* layout
, Read_relocs_data
* rd
)
1063 { return this->do_gc_process_relocs(symtab
, layout
, rd
); }
1065 // Scan the relocs and adjust the symbol table.
1067 scan_relocs(Symbol_table
* symtab
, Layout
* layout
, Read_relocs_data
* rd
)
1068 { return this->do_scan_relocs(symtab
, layout
, rd
); }
1070 // Return the value of the local symbol whose index is SYMNDX, plus
1071 // ADDEND. ADDEND is passed in so that we can correctly handle the
1072 // section symbol for a merge section.
1074 local_symbol_value(unsigned int symndx
, uint64_t addend
) const
1075 { return this->do_local_symbol_value(symndx
, addend
); }
1077 // Return the PLT offset for a local symbol. It is an error to call
1078 // this if it doesn't have one.
1080 local_plt_offset(unsigned int symndx
) const
1081 { return this->do_local_plt_offset(symndx
); }
1083 // Return whether the local symbol SYMNDX has a GOT offset of type
1086 local_has_got_offset(unsigned int symndx
, unsigned int got_type
) const
1087 { return this->do_local_has_got_offset(symndx
, got_type
); }
1089 // Return the GOT offset of type GOT_TYPE of the local symbol
1090 // SYMNDX. It is an error to call this if the symbol does not have
1091 // a GOT offset of the specified type.
1093 local_got_offset(unsigned int symndx
, unsigned int got_type
) const
1094 { return this->do_local_got_offset(symndx
, got_type
); }
1096 // Set the GOT offset with type GOT_TYPE of the local symbol SYMNDX
1099 set_local_got_offset(unsigned int symndx
, unsigned int got_type
,
1100 unsigned int got_offset
)
1101 { this->do_set_local_got_offset(symndx
, got_type
, got_offset
); }
1103 // Return whether the local symbol SYMNDX is a TLS symbol.
1105 local_is_tls(unsigned int symndx
) const
1106 { return this->do_local_is_tls(symndx
); }
1108 // The number of local symbols in the input symbol table.
1109 virtual unsigned int
1110 local_symbol_count() const
1111 { return this->do_local_symbol_count(); }
1113 // The number of local symbols in the output symbol table.
1114 virtual unsigned int
1115 output_local_symbol_count() const
1116 { return this->do_output_local_symbol_count(); }
1118 // The file offset for local symbols in the output symbol table.
1120 local_symbol_offset() const
1121 { return this->do_local_symbol_offset(); }
1123 // Initial local symbol processing: count the number of local symbols
1124 // in the output symbol table and dynamic symbol table; add local symbol
1125 // names to *POOL and *DYNPOOL.
1127 count_local_symbols(Stringpool_template
<char>* pool
,
1128 Stringpool_template
<char>* dynpool
)
1129 { return this->do_count_local_symbols(pool
, dynpool
); }
1131 // Set the values of the local symbols, set the output symbol table
1132 // indexes for the local variables, and set the offset where local
1133 // symbol information will be stored. Returns the new local symbol index.
1135 finalize_local_symbols(unsigned int index
, off_t off
, Symbol_table
* symtab
)
1136 { return this->do_finalize_local_symbols(index
, off
, symtab
); }
1138 // Set the output dynamic symbol table indexes for the local variables.
1140 set_local_dynsym_indexes(unsigned int index
)
1141 { return this->do_set_local_dynsym_indexes(index
); }
1143 // Set the offset where local dynamic symbol information will be stored.
1145 set_local_dynsym_offset(off_t off
)
1146 { return this->do_set_local_dynsym_offset(off
); }
1148 // Record a dynamic relocation against an input section from this object.
1150 add_dyn_reloc(unsigned int index
)
1152 if (this->dyn_reloc_count_
== 0)
1153 this->first_dyn_reloc_
= index
;
1154 ++this->dyn_reloc_count_
;
1157 // Return the index of the first dynamic relocation.
1159 first_dyn_reloc() const
1160 { return this->first_dyn_reloc_
; }
1162 // Return the count of dynamic relocations.
1164 dyn_reloc_count() const
1165 { return this->dyn_reloc_count_
; }
1167 // Relocate the input sections and write out the local symbols.
1169 relocate(const Symbol_table
* symtab
, const Layout
* layout
, Output_file
* of
)
1170 { return this->do_relocate(symtab
, layout
, of
); }
1172 // Return whether an input section is being included in the link.
1174 is_section_included(unsigned int shndx
) const
1176 gold_assert(shndx
< this->output_sections_
.size());
1177 return this->output_sections_
[shndx
] != NULL
;
1180 // The output section of the input section with index SHNDX.
1181 // This is only used currently to remove a section from the link in
1184 set_output_section(unsigned int shndx
, Output_section
* os
)
1186 gold_assert(shndx
< this->output_sections_
.size());
1187 this->output_sections_
[shndx
] = os
;
1190 // Set the offset of an input section within its output section.
1192 set_section_offset(unsigned int shndx
, uint64_t off
)
1193 { this->do_set_section_offset(shndx
, off
); }
1195 // Return true if we need to wait for output sections to be written
1196 // before we can apply relocations. This is true if the object has
1197 // any relocations for sections which require special handling, such
1198 // as the exception frame section.
1200 relocs_must_follow_section_writes() const
1201 { return this->relocs_must_follow_section_writes_
; }
1203 // Return the object merge map.
1206 { return this->object_merge_map_
; }
1208 // Set the object merge map.
1210 set_merge_map(Object_merge_map
* object_merge_map
)
1212 gold_assert(this->object_merge_map_
== NULL
);
1213 this->object_merge_map_
= object_merge_map
;
1216 // Record the relocatable reloc info for an input reloc section.
1218 set_relocatable_relocs(unsigned int reloc_shndx
, Relocatable_relocs
* rr
)
1220 gold_assert(reloc_shndx
< this->shnum());
1221 (*this->map_to_relocatable_relocs_
)[reloc_shndx
] = rr
;
1224 // Get the relocatable reloc info for an input reloc section.
1226 relocatable_relocs(unsigned int reloc_shndx
)
1228 gold_assert(reloc_shndx
< this->shnum());
1229 return (*this->map_to_relocatable_relocs_
)[reloc_shndx
];
1232 // Layout sections whose layout was deferred while waiting for
1233 // input files from a plugin.
1235 layout_deferred_sections(Layout
* layout
)
1236 { this->do_layout_deferred_sections(layout
); }
1238 // Return the index of the first incremental relocation for symbol SYMNDX.
1239 virtual unsigned int
1240 do_get_incremental_reloc_base(unsigned int symndx
) const
1241 { return this->reloc_bases_
[symndx
]; }
1243 // Return the number of incremental relocations for symbol SYMNDX.
1244 virtual unsigned int
1245 do_get_incremental_reloc_count(unsigned int symndx
) const
1246 { return this->reloc_counts_
[symndx
]; }
1248 // Return the word size of the object file.
1251 { return this->do_elfsize(); }
1253 // Return TRUE if this is a big-endian object file.
1255 is_big_endian() const
1256 { return this->do_is_big_endian(); }
1259 // The output section to be used for each input section, indexed by
1260 // the input section number. The output section is NULL if the
1261 // input section is to be discarded.
1262 typedef std::vector
<Output_section
*> Output_sections
;
1264 // Read the relocs--implemented by child class.
1266 do_read_relocs(Read_relocs_data
*) = 0;
1268 // Process the relocs--implemented by child class.
1270 do_gc_process_relocs(Symbol_table
*, Layout
*, Read_relocs_data
*) = 0;
1272 // Scan the relocs--implemented by child class.
1274 do_scan_relocs(Symbol_table
*, Layout
*, Read_relocs_data
*) = 0;
1276 // Return the value of a local symbol.
1278 do_local_symbol_value(unsigned int symndx
, uint64_t addend
) const = 0;
1280 // Return the PLT offset of a local symbol.
1281 virtual unsigned int
1282 do_local_plt_offset(unsigned int symndx
) const = 0;
1284 // Return whether a local symbol has a GOT offset of a given type.
1286 do_local_has_got_offset(unsigned int symndx
,
1287 unsigned int got_type
) const = 0;
1289 // Return the GOT offset of a given type of a local symbol.
1290 virtual unsigned int
1291 do_local_got_offset(unsigned int symndx
, unsigned int got_type
) const = 0;
1293 // Set the GOT offset with a given type for a local symbol.
1295 do_set_local_got_offset(unsigned int symndx
, unsigned int got_type
,
1296 unsigned int got_offset
) = 0;
1298 // Return whether local symbol SYMNDX is a TLS symbol.
1300 do_local_is_tls(unsigned int symndx
) const = 0;
1302 // Return the number of local symbols--implemented by child class.
1303 virtual unsigned int
1304 do_local_symbol_count() const = 0;
1306 // Return the number of output local symbols--implemented by child class.
1307 virtual unsigned int
1308 do_output_local_symbol_count() const = 0;
1310 // Return the file offset for local symbols--implemented by child class.
1312 do_local_symbol_offset() const = 0;
1314 // Count local symbols--implemented by child class.
1316 do_count_local_symbols(Stringpool_template
<char>*,
1317 Stringpool_template
<char>*) = 0;
1319 // Finalize the local symbols. Set the output symbol table indexes
1320 // for the local variables, and set the offset where local symbol
1321 // information will be stored.
1322 virtual unsigned int
1323 do_finalize_local_symbols(unsigned int, off_t
, Symbol_table
*) = 0;
1325 // Set the output dynamic symbol table indexes for the local variables.
1326 virtual unsigned int
1327 do_set_local_dynsym_indexes(unsigned int) = 0;
1329 // Set the offset where local dynamic symbol information will be stored.
1330 virtual unsigned int
1331 do_set_local_dynsym_offset(off_t
) = 0;
1333 // Relocate the input sections and write out the local
1334 // symbols--implemented by child class.
1336 do_relocate(const Symbol_table
* symtab
, const Layout
*, Output_file
* of
) = 0;
1338 // Set the offset of a section--implemented by child class.
1340 do_set_section_offset(unsigned int shndx
, uint64_t off
) = 0;
1342 // Layout sections whose layout was deferred while waiting for
1343 // input files from a plugin--implemented by child class.
1345 do_layout_deferred_sections(Layout
*) = 0;
1347 // Given a section index, return the corresponding Output_section.
1348 // The return value will be NULL if the section is not included in
1351 do_output_section(unsigned int shndx
) const
1353 gold_assert(shndx
< this->output_sections_
.size());
1354 return this->output_sections_
[shndx
];
1357 // Return the vector mapping input sections to output sections.
1360 { return this->output_sections_
; }
1362 const Output_sections
&
1363 output_sections() const
1364 { return this->output_sections_
; }
1366 // Set the size of the relocatable relocs array.
1368 size_relocatable_relocs()
1370 this->map_to_relocatable_relocs_
=
1371 new std::vector
<Relocatable_relocs
*>(this->shnum());
1374 // Record that we must wait for the output sections to be written
1375 // before applying relocations.
1377 set_relocs_must_follow_section_writes()
1378 { this->relocs_must_follow_section_writes_
= true; }
1380 // Allocate the array for counting incremental relocations.
1382 allocate_incremental_reloc_counts()
1384 unsigned int nsyms
= this->do_get_global_symbols()->size();
1385 this->reloc_counts_
= new unsigned int[nsyms
];
1386 gold_assert(this->reloc_counts_
!= NULL
);
1387 memset(this->reloc_counts_
, 0, nsyms
* sizeof(unsigned int));
1390 // Record a relocation in this object referencing global symbol SYMNDX.
1391 // Used for tracking incremental link information.
1393 count_incremental_reloc(unsigned int symndx
)
1395 unsigned int nsyms
= this->do_get_global_symbols()->size();
1396 gold_assert(symndx
< nsyms
);
1397 gold_assert(this->reloc_counts_
!= NULL
);
1398 ++this->reloc_counts_
[symndx
];
1401 // Finalize the incremental relocation information.
1403 finalize_incremental_relocs(Layout
* layout
, bool clear_counts
);
1405 // Return the index of the next relocation to be written for global symbol
1406 // SYMNDX. Only valid after finalize_incremental_relocs() has been called.
1408 next_incremental_reloc_index(unsigned int symndx
)
1410 unsigned int nsyms
= this->do_get_global_symbols()->size();
1412 gold_assert(this->reloc_counts_
!= NULL
);
1413 gold_assert(this->reloc_bases_
!= NULL
);
1414 gold_assert(symndx
< nsyms
);
1416 unsigned int counter
= this->reloc_counts_
[symndx
]++;
1417 return this->reloc_bases_
[symndx
] + counter
;
1420 // Return the word size of the object file--
1421 // implemented by child class.
1423 do_elfsize() const = 0;
1425 // Return TRUE if this is a big-endian object file--
1426 // implemented by child class.
1428 do_is_big_endian() const = 0;
1431 // Mapping from input sections to output section.
1432 Output_sections output_sections_
;
1433 // Mapping from input section index to the information recorded for
1434 // the relocations. This is only used for a relocatable link.
1435 std::vector
<Relocatable_relocs
*>* map_to_relocatable_relocs_
;
1436 // Mappings for merge sections. This is managed by the code in the
1438 Object_merge_map
* object_merge_map_
;
1439 // Whether we need to wait for output sections to be written before
1440 // we can apply relocations.
1441 bool relocs_must_follow_section_writes_
;
1442 // Used to store the relocs data computed by the Read_relocs pass.
1443 // Used during garbage collection of unused sections.
1444 Read_relocs_data
* rd_
;
1445 // Used to store the symbols data computed by the Read_symbols pass.
1446 // Again used during garbage collection when laying out referenced
1448 gold::Symbols_data
* sd_
;
1449 // Per-symbol counts of relocations, for incremental links.
1450 unsigned int* reloc_counts_
;
1451 // Per-symbol base indexes of relocations, for incremental links.
1452 unsigned int* reloc_bases_
;
1453 // Index of the first dynamic relocation for this object.
1454 unsigned int first_dyn_reloc_
;
1455 // Count of dynamic relocations for this object.
1456 unsigned int dyn_reloc_count_
;
1459 // This class is used to handle relocations against a section symbol
1460 // in an SHF_MERGE section. For such a symbol, we need to know the
1461 // addend of the relocation before we can determine the final value.
1462 // The addend gives us the location in the input section, and we can
1463 // determine how it is mapped to the output section. For a
1464 // non-section symbol, we apply the addend to the final value of the
1465 // symbol; that is done in finalize_local_symbols, and does not use
1469 class Merged_symbol_value
1472 typedef typename
elfcpp::Elf_types
<size
>::Elf_Addr Value
;
1474 // We use a hash table to map offsets in the input section to output
1476 typedef Unordered_map
<section_offset_type
, Value
> Output_addresses
;
1478 Merged_symbol_value(Value input_value
, Value output_start_address
)
1479 : input_value_(input_value
), output_start_address_(output_start_address
),
1483 // Initialize the hash table.
1485 initialize_input_to_output_map(const Relobj
*, unsigned int input_shndx
);
1487 // Release the hash table to save space.
1489 free_input_to_output_map()
1490 { this->output_addresses_
.clear(); }
1492 // Get the output value corresponding to an addend. The object and
1493 // input section index are passed in because the caller will have
1494 // them; otherwise we could store them here.
1496 value(const Relobj
* object
, unsigned int input_shndx
, Value addend
) const
1498 // This is a relocation against a section symbol. ADDEND is the
1499 // offset in the section. The result should be the start of some
1500 // merge area. If the object file wants something else, it should
1501 // use a regular symbol rather than a section symbol.
1502 // Unfortunately, PR 6658 shows a case in which the object file
1503 // refers to the section symbol, but uses a negative ADDEND to
1504 // compensate for a PC relative reloc. We can't handle the
1505 // general case. However, we can handle the special case of a
1506 // negative addend, by assuming that it refers to the start of the
1507 // section. Of course, that means that we have to guess when
1508 // ADDEND is negative. It is normal to see a 32-bit value here
1509 // even when the template parameter size is 64, as 64-bit object
1510 // file formats have 32-bit relocations. We know this is a merge
1511 // section, so we know it has to fit into memory. So we assume
1512 // that we won't see a value larger than a large 32-bit unsigned
1513 // value. This will break objects with very very large merge
1514 // sections; they probably break in other ways anyhow.
1515 Value input_offset
= this->input_value_
;
1516 if (addend
< 0xffffff00)
1518 input_offset
+= addend
;
1521 typename
Output_addresses::const_iterator p
=
1522 this->output_addresses_
.find(input_offset
);
1523 if (p
!= this->output_addresses_
.end())
1524 return p
->second
+ addend
;
1526 return (this->value_from_output_section(object
, input_shndx
, input_offset
)
1531 // Get the output value for an input offset if we couldn't find it
1532 // in the hash table.
1534 value_from_output_section(const Relobj
*, unsigned int input_shndx
,
1535 Value input_offset
) const;
1537 // The value of the section symbol in the input file. This is
1538 // normally zero, but could in principle be something else.
1540 // The start address of this merged section in the output file.
1541 Value output_start_address_
;
1542 // A hash table which maps offsets in the input section to output
1543 // addresses. This only maps specific offsets, not all offsets.
1544 Output_addresses output_addresses_
;
1547 // This POD class is holds the value of a symbol. This is used for
1548 // local symbols, and for all symbols during relocation processing.
1549 // For special sections, such as SHF_MERGE sections, this calls a
1550 // function to get the final symbol value.
1556 typedef typename
elfcpp::Elf_types
<size
>::Elf_Addr Value
;
1559 : output_symtab_index_(0), output_dynsym_index_(-1U), input_shndx_(0),
1560 is_ordinary_shndx_(false), is_section_symbol_(false),
1561 is_tls_symbol_(false), is_ifunc_symbol_(false), has_output_value_(true)
1562 { this->u_
.value
= 0; }
1566 if (!this->has_output_value_
)
1567 delete this->u_
.merged_symbol_value
;
1570 // Get the value of this symbol. OBJECT is the object in which this
1571 // symbol is defined, and ADDEND is an addend to add to the value.
1572 template<bool big_endian
>
1574 value(const Sized_relobj_file
<size
, big_endian
>* object
, Value addend
) const
1576 if (this->has_output_value_
)
1577 return this->u_
.value
+ addend
;
1580 gold_assert(this->is_ordinary_shndx_
);
1581 return this->u_
.merged_symbol_value
->value(object
, this->input_shndx_
,
1586 // Set the value of this symbol in the output symbol table.
1588 set_output_value(Value value
)
1589 { this->u_
.value
= value
; }
1591 // For a section symbol in a merged section, we need more
1594 set_merged_symbol_value(Merged_symbol_value
<size
>* msv
)
1596 gold_assert(this->is_section_symbol_
);
1597 this->has_output_value_
= false;
1598 this->u_
.merged_symbol_value
= msv
;
1601 // Initialize the input to output map for a section symbol in a
1602 // merged section. We also initialize the value of a non-section
1603 // symbol in a merged section.
1605 initialize_input_to_output_map(const Relobj
* object
)
1607 if (!this->has_output_value_
)
1609 gold_assert(this->is_section_symbol_
&& this->is_ordinary_shndx_
);
1610 Merged_symbol_value
<size
>* msv
= this->u_
.merged_symbol_value
;
1611 msv
->initialize_input_to_output_map(object
, this->input_shndx_
);
1615 // Free the input to output map for a section symbol in a merged
1618 free_input_to_output_map()
1620 if (!this->has_output_value_
)
1621 this->u_
.merged_symbol_value
->free_input_to_output_map();
1624 // Set the value of the symbol from the input file. This is only
1625 // called by count_local_symbols, to communicate the value to
1626 // finalize_local_symbols.
1628 set_input_value(Value value
)
1629 { this->u_
.value
= value
; }
1631 // Return the input value. This is only called by
1632 // finalize_local_symbols and (in special cases) relocate_section.
1635 { return this->u_
.value
; }
1637 // Return whether we have set the index in the output symbol table
1640 is_output_symtab_index_set() const
1642 return (this->output_symtab_index_
!= 0
1643 && this->output_symtab_index_
!= -2U);
1646 // Return whether this symbol may be discarded from the normal
1649 may_be_discarded_from_output_symtab() const
1651 gold_assert(!this->is_output_symtab_index_set());
1652 return this->output_symtab_index_
!= -2U;
1655 // Return whether this symbol has an entry in the output symbol
1658 has_output_symtab_entry() const
1660 gold_assert(this->is_output_symtab_index_set());
1661 return this->output_symtab_index_
!= -1U;
1664 // Return the index in the output symbol table.
1666 output_symtab_index() const
1668 gold_assert(this->is_output_symtab_index_set()
1669 && this->output_symtab_index_
!= -1U);
1670 return this->output_symtab_index_
;
1673 // Set the index in the output symbol table.
1675 set_output_symtab_index(unsigned int i
)
1677 gold_assert(!this->is_output_symtab_index_set());
1678 gold_assert(i
!= 0 && i
!= -1U && i
!= -2U);
1679 this->output_symtab_index_
= i
;
1682 // Record that this symbol should not go into the output symbol
1685 set_no_output_symtab_entry()
1687 gold_assert(this->output_symtab_index_
== 0);
1688 this->output_symtab_index_
= -1U;
1691 // Record that this symbol must go into the output symbol table,
1692 // because it there is a relocation that uses it.
1694 set_must_have_output_symtab_entry()
1696 gold_assert(!this->is_output_symtab_index_set());
1697 this->output_symtab_index_
= -2U;
1700 // Set the index in the output dynamic symbol table.
1702 set_needs_output_dynsym_entry()
1704 gold_assert(!this->is_section_symbol());
1705 this->output_dynsym_index_
= 0;
1708 // Return whether this symbol should go into the dynamic symbol
1711 needs_output_dynsym_entry() const
1713 return this->output_dynsym_index_
!= -1U;
1716 // Return whether this symbol has an entry in the dynamic symbol
1719 has_output_dynsym_entry() const
1721 gold_assert(this->output_dynsym_index_
!= 0);
1722 return this->output_dynsym_index_
!= -1U;
1725 // Record that this symbol should go into the dynamic symbol table.
1727 set_output_dynsym_index(unsigned int i
)
1729 gold_assert(this->output_dynsym_index_
== 0);
1730 gold_assert(i
!= 0 && i
!= -1U);
1731 this->output_dynsym_index_
= i
;
1734 // Return the index in the output dynamic symbol table.
1736 output_dynsym_index() const
1738 gold_assert(this->output_dynsym_index_
!= 0
1739 && this->output_dynsym_index_
!= -1U);
1740 return this->output_dynsym_index_
;
1743 // Set the index of the input section in the input file.
1745 set_input_shndx(unsigned int i
, bool is_ordinary
)
1747 this->input_shndx_
= i
;
1748 // input_shndx_ field is a bitfield, so make sure that the value
1750 gold_assert(this->input_shndx_
== i
);
1751 this->is_ordinary_shndx_
= is_ordinary
;
1754 // Return the index of the input section in the input file.
1756 input_shndx(bool* is_ordinary
) const
1758 *is_ordinary
= this->is_ordinary_shndx_
;
1759 return this->input_shndx_
;
1762 // Whether this is a section symbol.
1764 is_section_symbol() const
1765 { return this->is_section_symbol_
; }
1767 // Record that this is a section symbol.
1769 set_is_section_symbol()
1771 gold_assert(!this->needs_output_dynsym_entry());
1772 this->is_section_symbol_
= true;
1775 // Record that this is a TLS symbol.
1778 { this->is_tls_symbol_
= true; }
1780 // Return true if this is a TLS symbol.
1782 is_tls_symbol() const
1783 { return this->is_tls_symbol_
; }
1785 // Record that this is an IFUNC symbol.
1787 set_is_ifunc_symbol()
1788 { this->is_ifunc_symbol_
= true; }
1790 // Return true if this is an IFUNC symbol.
1792 is_ifunc_symbol() const
1793 { return this->is_ifunc_symbol_
; }
1795 // Return true if this has output value.
1797 has_output_value() const
1798 { return this->has_output_value_
; }
1801 // The index of this local symbol in the output symbol table. This
1802 // will be 0 if no value has been assigned yet, and the symbol may
1803 // be omitted. This will be -1U if the symbol should not go into
1804 // the symbol table. This will be -2U if the symbol must go into
1805 // the symbol table, but no index has been assigned yet.
1806 unsigned int output_symtab_index_
;
1807 // The index of this local symbol in the dynamic symbol table. This
1808 // will be -1U if the symbol should not go into the symbol table.
1809 unsigned int output_dynsym_index_
;
1810 // The section index in the input file in which this symbol is
1812 unsigned int input_shndx_
: 27;
1813 // Whether the section index is an ordinary index, not a special
1815 bool is_ordinary_shndx_
: 1;
1816 // Whether this is a STT_SECTION symbol.
1817 bool is_section_symbol_
: 1;
1818 // Whether this is a STT_TLS symbol.
1819 bool is_tls_symbol_
: 1;
1820 // Whether this is a STT_GNU_IFUNC symbol.
1821 bool is_ifunc_symbol_
: 1;
1822 // Whether this symbol has a value for the output file. This is
1823 // normally set to true during Layout::finalize, by
1824 // finalize_local_symbols. It will be false for a section symbol in
1825 // a merge section, as for such symbols we can not determine the
1826 // value to use in a relocation until we see the addend.
1827 bool has_output_value_
: 1;
1830 // This is used if has_output_value_ is true. Between
1831 // count_local_symbols and finalize_local_symbols, this is the
1832 // value in the input file. After finalize_local_symbols, it is
1833 // the value in the output file.
1835 // This is used if has_output_value_ is false. It points to the
1836 // information we need to get the value for a merge section.
1837 Merged_symbol_value
<size
>* merged_symbol_value
;
1841 // This type is used to modify relocations for -fsplit-stack. It is
1842 // indexed by relocation index, and means that the relocation at that
1843 // index should use the symbol from the vector, rather than the one
1844 // indicated by the relocation.
1846 class Reloc_symbol_changes
1849 Reloc_symbol_changes(size_t count
)
1854 set(size_t i
, Symbol
* sym
)
1855 { this->vec_
[i
] = sym
; }
1858 operator[](size_t i
) const
1859 { return this->vec_
[i
]; }
1862 std::vector
<Symbol
*> vec_
;
1865 // Type for mapping section index to uncompressed size and contents.
1867 struct Compressed_section_info
1869 section_size_type size
;
1870 const unsigned char* contents
;
1872 typedef std::map
<unsigned int, Compressed_section_info
> Compressed_section_map
;
1874 // Abstract base class for a regular object file, either a real object file
1875 // or an incremental (unchanged) object. This is size and endian specific.
1877 template<int size
, bool big_endian
>
1878 class Sized_relobj
: public Relobj
1881 typedef typename
elfcpp::Elf_types
<size
>::Elf_Addr Address
;
1882 typedef Relobj::Symbols Symbols
;
1884 static const Address invalid_address
= static_cast<Address
>(0) - 1;
1886 Sized_relobj(const std::string
& name
, Input_file
* input_file
)
1887 : Relobj(name
, input_file
), local_got_offsets_(), section_offsets_()
1890 Sized_relobj(const std::string
& name
, Input_file
* input_file
,
1892 : Relobj(name
, input_file
, offset
), local_got_offsets_(), section_offsets_()
1898 // If this is a regular object, return a pointer to the Sized_relobj_file
1899 // object. Otherwise, return NULL.
1900 virtual Sized_relobj_file
<size
, big_endian
>*
1904 const virtual Sized_relobj_file
<size
, big_endian
>*
1905 sized_relobj() const
1908 // Checks if the offset of input section SHNDX within its output
1909 // section is invalid.
1911 is_output_section_offset_invalid(unsigned int shndx
) const
1912 { return this->get_output_section_offset(shndx
) == invalid_address
; }
1914 // Get the offset of input section SHNDX within its output section.
1915 // This is -1 if the input section requires a special mapping, such
1916 // as a merge section. The output section can be found in the
1917 // output_sections_ field of the parent class Relobj.
1919 get_output_section_offset(unsigned int shndx
) const
1921 gold_assert(shndx
< this->section_offsets_
.size());
1922 return this->section_offsets_
[shndx
];
1925 // Iterate over local symbols, calling a visitor class V for each GOT offset
1926 // associated with a local symbol.
1928 do_for_all_local_got_entries(Got_offset_list::Visitor
* v
) const;
1931 typedef Relobj::Output_sections Output_sections
;
1933 // Clear the local symbol information.
1936 { this->local_got_offsets_
.clear(); }
1938 // Return the vector of section offsets.
1939 std::vector
<Address
>&
1941 { return this->section_offsets_
; }
1943 // Get the address of an output section.
1945 do_output_section_address(unsigned int shndx
);
1947 // Get the offset of a section.
1949 do_output_section_offset(unsigned int shndx
) const
1951 Address off
= this->get_output_section_offset(shndx
);
1952 if (off
== invalid_address
)
1957 // Set the offset of a section.
1959 do_set_section_offset(unsigned int shndx
, uint64_t off
)
1961 gold_assert(shndx
< this->section_offsets_
.size());
1962 this->section_offsets_
[shndx
] =
1963 (off
== static_cast<uint64_t>(-1)
1965 : convert_types
<Address
, uint64_t>(off
));
1968 // Return whether the local symbol SYMNDX has a GOT offset of type
1971 do_local_has_got_offset(unsigned int symndx
, unsigned int got_type
) const
1973 Local_got_offsets::const_iterator p
=
1974 this->local_got_offsets_
.find(symndx
);
1975 return (p
!= this->local_got_offsets_
.end()
1976 && p
->second
->get_offset(got_type
) != -1U);
1979 // Return the GOT offset of type GOT_TYPE of the local symbol
1982 do_local_got_offset(unsigned int symndx
, unsigned int got_type
) const
1984 Local_got_offsets::const_iterator p
=
1985 this->local_got_offsets_
.find(symndx
);
1986 gold_assert(p
!= this->local_got_offsets_
.end());
1987 unsigned int off
= p
->second
->get_offset(got_type
);
1988 gold_assert(off
!= -1U);
1992 // Set the GOT offset with type GOT_TYPE of the local symbol SYMNDX
1995 do_set_local_got_offset(unsigned int symndx
, unsigned int got_type
,
1996 unsigned int got_offset
)
1998 Local_got_offsets::const_iterator p
=
1999 this->local_got_offsets_
.find(symndx
);
2000 if (p
!= this->local_got_offsets_
.end())
2001 p
->second
->set_offset(got_type
, got_offset
);
2004 Got_offset_list
* g
= new Got_offset_list(got_type
, got_offset
);
2005 std::pair
<Local_got_offsets::iterator
, bool> ins
=
2006 this->local_got_offsets_
.insert(std::make_pair(symndx
, g
));
2007 gold_assert(ins
.second
);
2011 // Return the word size of the object file.
2016 // Return TRUE if this is a big-endian object file.
2018 do_is_big_endian() const
2019 { return big_endian
; }
2022 // The GOT offsets of local symbols. This map also stores GOT offsets
2023 // for tp-relative offsets for TLS symbols.
2024 typedef Unordered_map
<unsigned int, Got_offset_list
*> Local_got_offsets
;
2026 // GOT offsets for local non-TLS symbols, and tp-relative offsets
2027 // for TLS symbols, indexed by symbol number.
2028 Local_got_offsets local_got_offsets_
;
2029 // For each input section, the offset of the input section in its
2030 // output section. This is INVALID_ADDRESS if the input section requires a
2032 std::vector
<Address
> section_offsets_
;
2035 // A regular object file. This is size and endian specific.
2037 template<int size
, bool big_endian
>
2038 class Sized_relobj_file
: public Sized_relobj
<size
, big_endian
>
2041 typedef typename
elfcpp::Elf_types
<size
>::Elf_Addr Address
;
2042 typedef typename Sized_relobj
<size
, big_endian
>::Symbols Symbols
;
2043 typedef std::vector
<Symbol_value
<size
> > Local_values
;
2045 static const Address invalid_address
= static_cast<Address
>(0) - 1;
2047 enum Compute_final_local_value_status
2051 // An error occurred.
2053 // The local symbol has no output section.
2057 Sized_relobj_file(const std::string
& name
,
2058 Input_file
* input_file
,
2060 const typename
elfcpp::Ehdr
<size
, big_endian
>&);
2062 ~Sized_relobj_file();
2064 // Set up the object file based on TARGET.
2067 { this->do_setup(); }
2069 // Return a pointer to the Sized_relobj_file object.
2070 Sized_relobj_file
<size
, big_endian
>*
2074 const Sized_relobj_file
<size
, big_endian
>*
2075 sized_relobj() const
2078 // Return the ELF file type.
2081 { return this->e_type_
; }
2083 // Return the number of symbols. This is only valid after
2084 // Object::add_symbols has been called.
2086 symbol_count() const
2087 { return this->local_symbol_count_
+ this->symbols_
.size(); }
2089 // If SYM is the index of a global symbol in the object file's
2090 // symbol table, return the Symbol object. Otherwise, return NULL.
2092 global_symbol(unsigned int sym
) const
2094 if (sym
>= this->local_symbol_count_
)
2096 gold_assert(sym
- this->local_symbol_count_
< this->symbols_
.size());
2097 return this->symbols_
[sym
- this->local_symbol_count_
];
2102 // Return the section index of symbol SYM. Set *VALUE to its value
2103 // in the object file. Set *IS_ORDINARY if this is an ordinary
2104 // section index, not a special code between SHN_LORESERVE and
2105 // SHN_HIRESERVE. Note that for a symbol which is not defined in
2106 // this object file, this will set *VALUE to 0 and return SHN_UNDEF;
2107 // it will not return the final value of the symbol in the link.
2109 symbol_section_and_value(unsigned int sym
, Address
* value
, bool* is_ordinary
);
2111 // Return a pointer to the Symbol_value structure which holds the
2112 // value of a local symbol.
2113 const Symbol_value
<size
>*
2114 local_symbol(unsigned int sym
) const
2116 gold_assert(sym
< this->local_values_
.size());
2117 return &this->local_values_
[sym
];
2120 // Return the index of local symbol SYM in the ordinary symbol
2121 // table. A value of -1U means that the symbol is not being output.
2123 symtab_index(unsigned int sym
) const
2125 gold_assert(sym
< this->local_values_
.size());
2126 return this->local_values_
[sym
].output_symtab_index();
2129 // Return the index of local symbol SYM in the dynamic symbol
2130 // table. A value of -1U means that the symbol is not being output.
2132 dynsym_index(unsigned int sym
) const
2134 gold_assert(sym
< this->local_values_
.size());
2135 return this->local_values_
[sym
].output_dynsym_index();
2138 // Return the input section index of local symbol SYM.
2140 local_symbol_input_shndx(unsigned int sym
, bool* is_ordinary
) const
2142 gold_assert(sym
< this->local_values_
.size());
2143 return this->local_values_
[sym
].input_shndx(is_ordinary
);
2146 // Record that local symbol SYM must be in the output symbol table.
2148 set_must_have_output_symtab_entry(unsigned int sym
)
2150 gold_assert(sym
< this->local_values_
.size());
2151 this->local_values_
[sym
].set_must_have_output_symtab_entry();
2154 // Record that local symbol SYM needs a dynamic symbol entry.
2156 set_needs_output_dynsym_entry(unsigned int sym
)
2158 gold_assert(sym
< this->local_values_
.size());
2159 this->local_values_
[sym
].set_needs_output_dynsym_entry();
2162 // Return whether the local symbol SYMNDX has a PLT offset.
2164 local_has_plt_offset(unsigned int symndx
) const;
2166 // Set the PLT offset of the local symbol SYMNDX.
2168 set_local_plt_offset(unsigned int symndx
, unsigned int plt_offset
);
2170 // Adjust this local symbol value. Return false if the symbol
2171 // should be discarded from the output file.
2173 adjust_local_symbol(Symbol_value
<size
>* lv
) const
2174 { return this->do_adjust_local_symbol(lv
); }
2176 // Return the name of the symbol that spans the given offset in the
2177 // specified section in this object. This is used only for error
2178 // messages and is not particularly efficient.
2180 get_symbol_location_info(unsigned int shndx
, off_t offset
,
2181 Symbol_location_info
* info
);
2183 // Look for a kept section corresponding to the given discarded section,
2184 // and return its output address. This is used only for relocations in
2185 // debugging sections.
2187 map_to_kept_section(unsigned int shndx
, bool* found
) const;
2189 // Compute final local symbol value. R_SYM is the local symbol index.
2190 // LV_IN points to a local symbol value containing the input value.
2191 // LV_OUT points to a local symbol value storing the final output value,
2192 // which must not be a merged symbol value since before calling this
2193 // method to avoid memory leak. SYMTAB points to a symbol table.
2195 // The method returns a status code at return. If the return status is
2196 // CFLV_OK, *LV_OUT contains the final value. If the return status is
2197 // CFLV_ERROR, *LV_OUT is 0. If the return status is CFLV_DISCARDED,
2198 // *LV_OUT is not modified.
2199 Compute_final_local_value_status
2200 compute_final_local_value(unsigned int r_sym
,
2201 const Symbol_value
<size
>* lv_in
,
2202 Symbol_value
<size
>* lv_out
,
2203 const Symbol_table
* symtab
);
2206 typedef typename Sized_relobj
<size
, big_endian
>::Output_sections
2213 // Read the symbols.
2215 do_read_symbols(Read_symbols_data
*);
2217 // Return the value of a local symbol.
2219 do_local_symbol_value(unsigned int symndx
, uint64_t addend
) const
2221 const Symbol_value
<size
>* symval
= this->local_symbol(symndx
);
2222 return symval
->value(this, addend
);
2225 // Return the PLT offset for a local symbol. It is an error to call
2226 // this if it doesn't have one.
2228 do_local_plt_offset(unsigned int symndx
) const;
2230 // Return whether local symbol SYMNDX is a TLS symbol.
2232 do_local_is_tls(unsigned int symndx
) const
2233 { return this->local_symbol(symndx
)->is_tls_symbol(); }
2235 // Return the number of local symbols.
2237 do_local_symbol_count() const
2238 { return this->local_symbol_count_
; }
2240 // Return the number of local symbols in the output symbol table.
2242 do_output_local_symbol_count() const
2243 { return this->output_local_symbol_count_
; }
2245 // Return the number of local symbols in the output symbol table.
2247 do_local_symbol_offset() const
2248 { return this->local_symbol_offset_
; }
2250 // Lay out the input sections.
2252 do_layout(Symbol_table
*, Layout
*, Read_symbols_data
*);
2254 // Layout sections whose layout was deferred while waiting for
2255 // input files from a plugin.
2257 do_layout_deferred_sections(Layout
*);
2259 // Add the symbols to the symbol table.
2261 do_add_symbols(Symbol_table
*, Read_symbols_data
*, Layout
*);
2263 Archive::Should_include
2264 do_should_include_member(Symbol_table
* symtab
, Layout
*, Read_symbols_data
*,
2267 // Iterate over global symbols, calling a visitor class V for each.
2269 do_for_all_global_symbols(Read_symbols_data
* sd
,
2270 Library_base::Symbol_visitor_base
* v
);
2274 do_read_relocs(Read_relocs_data
*);
2276 // Process the relocs to find list of referenced sections. Used only
2277 // during garbage collection.
2279 do_gc_process_relocs(Symbol_table
*, Layout
*, Read_relocs_data
*);
2281 // Scan the relocs and adjust the symbol table.
2283 do_scan_relocs(Symbol_table
*, Layout
*, Read_relocs_data
*);
2285 // Count the local symbols.
2287 do_count_local_symbols(Stringpool_template
<char>*,
2288 Stringpool_template
<char>*);
2290 // Finalize the local symbols.
2292 do_finalize_local_symbols(unsigned int, off_t
, Symbol_table
*);
2294 // Set the offset where local dynamic symbol information will be stored.
2296 do_set_local_dynsym_indexes(unsigned int);
2298 // Set the offset where local dynamic symbol information will be stored.
2300 do_set_local_dynsym_offset(off_t
);
2302 // Relocate the input sections and write out the local symbols.
2304 do_relocate(const Symbol_table
* symtab
, const Layout
*, Output_file
* of
);
2306 // Get the size of a section.
2308 do_section_size(unsigned int shndx
)
2309 { return this->elf_file_
.section_size(shndx
); }
2311 // Get the name of a section.
2313 do_section_name(unsigned int shndx
)
2314 { return this->elf_file_
.section_name(shndx
); }
2316 // Return the location of the contents of a section.
2317 const unsigned char*
2318 do_section_contents(unsigned int shndx
, section_size_type
* plen
,
2321 Object::Location
loc(this->elf_file_
.section_contents(shndx
));
2322 *plen
= convert_to_section_size_type(loc
.data_size
);
2325 static const unsigned char empty
[1] = { '\0' };
2328 return this->get_view(loc
.file_offset
, *plen
, true, cache
);
2331 // Return section flags.
2333 do_section_flags(unsigned int shndx
);
2335 // Return section entsize.
2337 do_section_entsize(unsigned int shndx
);
2339 // Return section address.
2341 do_section_address(unsigned int shndx
)
2342 { return this->elf_file_
.section_addr(shndx
); }
2344 // Return section type.
2346 do_section_type(unsigned int shndx
)
2347 { return this->elf_file_
.section_type(shndx
); }
2349 // Return the section link field.
2351 do_section_link(unsigned int shndx
)
2352 { return this->elf_file_
.section_link(shndx
); }
2354 // Return the section info field.
2356 do_section_info(unsigned int shndx
)
2357 { return this->elf_file_
.section_info(shndx
); }
2359 // Return the section alignment.
2361 do_section_addralign(unsigned int shndx
)
2362 { return this->elf_file_
.section_addralign(shndx
); }
2364 // Return the Xindex structure to use.
2366 do_initialize_xindex();
2368 // Get symbol counts.
2370 do_get_global_symbol_counts(const Symbol_table
*, size_t*, size_t*) const;
2372 // Get the global symbols.
2374 do_get_global_symbols() const
2375 { return &this->symbols_
; }
2377 // Adjust a section index if necessary.
2379 adjust_shndx(unsigned int shndx
)
2381 if (shndx
>= elfcpp::SHN_LORESERVE
)
2382 shndx
+= this->elf_file_
.large_shndx_offset();
2386 // Initialize input to output maps for section symbols in merged
2389 initialize_input_to_output_maps();
2391 // Free the input to output maps for section symbols in merged
2394 free_input_to_output_maps();
2396 // Return symbol table section index.
2398 symtab_shndx() const
2399 { return this->symtab_shndx_
; }
2401 // Allow a child class to access the ELF file.
2402 elfcpp::Elf_file
<size
, big_endian
, Object
>*
2404 { return &this->elf_file_
; }
2406 // Allow a child class to access the local values.
2409 { return &this->local_values_
; }
2411 // Views and sizes when relocating.
2414 unsigned char* view
;
2415 typename
elfcpp::Elf_types
<size
>::Elf_Addr address
;
2417 section_size_type view_size
;
2418 bool is_input_output_view
;
2419 bool is_postprocessing_view
;
2420 bool is_ctors_reverse_view
;
2423 typedef std::vector
<View_size
> Views
;
2425 // Stash away info for a number of special sections.
2426 // Return true if any of the sections found require local symbols to be read.
2428 do_find_special_sections(Read_symbols_data
* sd
);
2430 // This may be overriden by a child class.
2432 do_relocate_sections(const Symbol_table
* symtab
, const Layout
* layout
,
2433 const unsigned char* pshdrs
, Output_file
* of
,
2436 // Adjust this local symbol value. Return false if the symbol
2437 // should be discarded from the output file.
2439 do_adjust_local_symbol(Symbol_value
<size
>*) const
2442 // Allow a child to set output local symbol count.
2444 set_output_local_symbol_count(unsigned int value
)
2445 { this->output_local_symbol_count_
= value
; }
2447 // Return TRUE if the section is a compressed debug section, and set
2448 // *UNCOMPRESSED_SIZE to the size of the uncompressed data.
2450 do_section_is_compressed(unsigned int shndx
,
2451 section_size_type
* uncompressed_size
) const
2453 if (this->compressed_sections_
== NULL
)
2455 Compressed_section_map::const_iterator p
=
2456 this->compressed_sections_
->find(shndx
);
2457 if (p
!= this->compressed_sections_
->end())
2459 if (uncompressed_size
!= NULL
)
2460 *uncompressed_size
= p
->second
.size
;
2466 // Return a view of the uncompressed contents of a section. Set *PLEN
2467 // to the size. Set *IS_NEW to true if the contents need to be deleted
2469 const unsigned char*
2470 do_decompressed_section_contents(unsigned int shndx
,
2471 section_size_type
* plen
,
2474 // Discard any buffers of decompressed sections. This is done
2475 // at the end of the Add_symbols task.
2477 do_discard_decompressed_sections();
2481 typedef Sized_relobj_file
<size
, big_endian
> This
;
2482 static const int ehdr_size
= elfcpp::Elf_sizes
<size
>::ehdr_size
;
2483 static const int shdr_size
= elfcpp::Elf_sizes
<size
>::shdr_size
;
2484 static const int sym_size
= elfcpp::Elf_sizes
<size
>::sym_size
;
2485 typedef elfcpp::Shdr
<size
, big_endian
> Shdr
;
2487 // To keep track of discarded comdat sections, we need to map a member
2488 // section index to the object and section index of the corresponding
2490 struct Kept_comdat_section
2492 Kept_comdat_section(Relobj
* a_object
, unsigned int a_shndx
)
2493 : object(a_object
), shndx(a_shndx
)
2498 typedef std::map
<unsigned int, Kept_comdat_section
>
2499 Kept_comdat_section_table
;
2501 // Find the SHT_SYMTAB section, given the section headers.
2503 find_symtab(const unsigned char* pshdrs
);
2505 // Return whether SHDR has the right flags for a GNU style exception
2508 check_eh_frame_flags(const elfcpp::Shdr
<size
, big_endian
>* shdr
) const;
2510 // Return whether there is a section named .eh_frame which might be
2511 // a GNU style exception frame section.
2513 find_eh_frame(const unsigned char* pshdrs
, const char* names
,
2514 section_size_type names_size
) const;
2516 // Whether to include a section group in the link.
2518 include_section_group(Symbol_table
*, Layout
*, unsigned int, const char*,
2519 const unsigned char*, const char*, section_size_type
,
2520 std::vector
<bool>*);
2522 // Whether to include a linkonce section in the link.
2524 include_linkonce_section(Layout
*, unsigned int, const char*,
2525 const elfcpp::Shdr
<size
, big_endian
>&);
2527 // Layout an input section.
2529 layout_section(Layout
* layout
, unsigned int shndx
, const char* name
,
2530 const typename
This::Shdr
& shdr
, unsigned int reloc_shndx
,
2531 unsigned int reloc_type
);
2533 // Layout an input .eh_frame section.
2535 layout_eh_frame_section(Layout
* layout
, const unsigned char* symbols_data
,
2536 section_size_type symbols_size
,
2537 const unsigned char* symbol_names_data
,
2538 section_size_type symbol_names_size
,
2539 unsigned int shndx
, const typename
This::Shdr
&,
2540 unsigned int reloc_shndx
, unsigned int reloc_type
);
2542 // Write section data to the output file. Record the views and
2543 // sizes in VIEWS for use when relocating.
2545 write_sections(const Layout
*, const unsigned char* pshdrs
, Output_file
*,
2548 // Relocate the sections in the output file.
2550 relocate_sections(const Symbol_table
* symtab
, const Layout
* layout
,
2551 const unsigned char* pshdrs
, Output_file
* of
,
2553 { this->do_relocate_sections(symtab
, layout
, pshdrs
, of
, pviews
); }
2555 // Reverse the words in a section. Used for .ctors sections mapped
2556 // to .init_array sections.
2558 reverse_words(unsigned char*, section_size_type
);
2560 // Scan the input relocations for --emit-relocs.
2562 emit_relocs_scan(Symbol_table
*, Layout
*, const unsigned char* plocal_syms
,
2563 const Read_relocs_data::Relocs_list::iterator
&);
2565 // Scan the input relocations for --emit-relocs, templatized on the
2566 // type of the relocation section.
2567 template<int sh_type
>
2569 emit_relocs_scan_reltype(Symbol_table
*, Layout
*,
2570 const unsigned char* plocal_syms
,
2571 const Read_relocs_data::Relocs_list::iterator
&,
2572 Relocatable_relocs
*);
2574 // Scan the input relocations for --incremental.
2576 incremental_relocs_scan(const Read_relocs_data::Relocs_list::iterator
&);
2578 // Scan the input relocations for --incremental, templatized on the
2579 // type of the relocation section.
2580 template<int sh_type
>
2582 incremental_relocs_scan_reltype(
2583 const Read_relocs_data::Relocs_list::iterator
&);
2586 incremental_relocs_write(const Relocate_info
<size
, big_endian
>*,
2587 unsigned int sh_type
,
2588 const unsigned char* prelocs
,
2591 Address output_offset
,
2594 template<int sh_type
>
2596 incremental_relocs_write_reltype(const Relocate_info
<size
, big_endian
>*,
2597 const unsigned char* prelocs
,
2600 Address output_offset
,
2603 // A type shared by split_stack_adjust_reltype and find_functions.
2604 typedef std::map
<section_offset_type
, section_size_type
> Function_offsets
;
2606 // Check for -fsplit-stack routines calling non-split-stack routines.
2608 split_stack_adjust(const Symbol_table
*, const unsigned char* pshdrs
,
2609 unsigned int sh_type
, unsigned int shndx
,
2610 const unsigned char* prelocs
, size_t reloc_count
,
2611 unsigned char* view
, section_size_type view_size
,
2612 Reloc_symbol_changes
** reloc_map
);
2614 template<int sh_type
>
2616 split_stack_adjust_reltype(const Symbol_table
*, const unsigned char* pshdrs
,
2617 unsigned int shndx
, const unsigned char* prelocs
,
2618 size_t reloc_count
, unsigned char* view
,
2619 section_size_type view_size
,
2620 Reloc_symbol_changes
** reloc_map
);
2622 // Find all functions in a section.
2624 find_functions(const unsigned char* pshdrs
, unsigned int shndx
,
2627 // Write out the local symbols.
2629 write_local_symbols(Output_file
*,
2630 const Stringpool_template
<char>*,
2631 const Stringpool_template
<char>*,
2632 Output_symtab_xindex
*,
2633 Output_symtab_xindex
*,
2636 // Record a mapping from discarded section SHNDX to the corresponding
2639 set_kept_comdat_section(unsigned int shndx
, Relobj
* kept_object
,
2640 unsigned int kept_shndx
)
2642 Kept_comdat_section
kept(kept_object
, kept_shndx
);
2643 this->kept_comdat_sections_
.insert(std::make_pair(shndx
, kept
));
2646 // Find the kept section corresponding to the discarded section
2647 // SHNDX. Return true if found.
2649 get_kept_comdat_section(unsigned int shndx
, Relobj
** kept_object
,
2650 unsigned int* kept_shndx
) const
2652 typename
Kept_comdat_section_table::const_iterator p
=
2653 this->kept_comdat_sections_
.find(shndx
);
2654 if (p
== this->kept_comdat_sections_
.end())
2656 *kept_object
= p
->second
.object
;
2657 *kept_shndx
= p
->second
.shndx
;
2661 // Compute final local symbol value. R_SYM is the local symbol index.
2662 // LV_IN points to a local symbol value containing the input value.
2663 // LV_OUT points to a local symbol value storing the final output value,
2664 // which must not be a merged symbol value since before calling this
2665 // method to avoid memory leak. RELOCATABLE indicates whether we are
2666 // linking a relocatable output. OUT_SECTIONS is an array of output
2667 // sections. OUT_OFFSETS is an array of offsets of the sections. SYMTAB
2668 // points to a symbol table.
2670 // The method returns a status code at return. If the return status is
2671 // CFLV_OK, *LV_OUT contains the final value. If the return status is
2672 // CFLV_ERROR, *LV_OUT is 0. If the return status is CFLV_DISCARDED,
2673 // *LV_OUT is not modified.
2674 inline Compute_final_local_value_status
2675 compute_final_local_value_internal(unsigned int r_sym
,
2676 const Symbol_value
<size
>* lv_in
,
2677 Symbol_value
<size
>* lv_out
,
2679 const Output_sections
& out_sections
,
2680 const std::vector
<Address
>& out_offsets
,
2681 const Symbol_table
* symtab
);
2683 // The PLT offsets of local symbols.
2684 typedef Unordered_map
<unsigned int, unsigned int> Local_plt_offsets
;
2686 // Saved information for sections whose layout was deferred.
2687 struct Deferred_layout
2689 static const int shdr_size
= elfcpp::Elf_sizes
<size
>::shdr_size
;
2690 Deferred_layout(unsigned int shndx
, const char* name
,
2691 const unsigned char* pshdr
,
2692 unsigned int reloc_shndx
, unsigned int reloc_type
)
2693 : shndx_(shndx
), name_(name
), reloc_shndx_(reloc_shndx
),
2694 reloc_type_(reloc_type
)
2696 memcpy(this->shdr_data_
, pshdr
, shdr_size
);
2698 unsigned int shndx_
;
2700 unsigned int reloc_shndx_
;
2701 unsigned int reloc_type_
;
2702 unsigned char shdr_data_
[shdr_size
];
2705 // General access to the ELF file.
2706 elfcpp::Elf_file
<size
, big_endian
, Object
> elf_file_
;
2707 // Type of ELF file (ET_REL or ET_EXEC). ET_EXEC files are allowed
2708 // as input files only for the --just-symbols option.
2710 // Index of SHT_SYMTAB section.
2711 unsigned int symtab_shndx_
;
2712 // The number of local symbols.
2713 unsigned int local_symbol_count_
;
2714 // The number of local symbols which go into the output file.
2715 unsigned int output_local_symbol_count_
;
2716 // The number of local symbols which go into the output file's dynamic
2718 unsigned int output_local_dynsym_count_
;
2719 // The entries in the symbol table for the external symbols.
2721 // Number of symbols defined in object file itself.
2722 size_t defined_count_
;
2723 // File offset for local symbols (relative to start of symbol table).
2724 off_t local_symbol_offset_
;
2725 // File offset for local dynamic symbols (absolute).
2726 off_t local_dynsym_offset_
;
2727 // Values of local symbols.
2728 Local_values local_values_
;
2729 // PLT offsets for local symbols.
2730 Local_plt_offsets local_plt_offsets_
;
2731 // Table mapping discarded comdat sections to corresponding kept sections.
2732 Kept_comdat_section_table kept_comdat_sections_
;
2733 // Whether this object has a GNU style .eh_frame section.
2735 // If this object has a GNU style .eh_frame section that is discarded in
2736 // output, record the index here. Otherwise it is -1U.
2737 unsigned int discarded_eh_frame_shndx_
;
2738 // The list of sections whose layout was deferred.
2739 std::vector
<Deferred_layout
> deferred_layout_
;
2740 // The list of relocation sections whose layout was deferred.
2741 std::vector
<Deferred_layout
> deferred_layout_relocs_
;
2742 // For compressed debug sections, map section index to uncompressed size
2744 Compressed_section_map
* compressed_sections_
;
2747 // A class to manage the list of all objects.
2753 : relobj_list_(), dynobj_list_(), sonames_(), cref_(NULL
)
2756 // The type of the list of input relocateable objects.
2757 typedef std::vector
<Relobj
*> Relobj_list
;
2758 typedef Relobj_list::const_iterator Relobj_iterator
;
2760 // The type of the list of input dynamic objects.
2761 typedef std::vector
<Dynobj
*> Dynobj_list
;
2762 typedef Dynobj_list::const_iterator Dynobj_iterator
;
2764 // Add an object to the list. Return true if all is well, or false
2765 // if this object should be ignored.
2767 add_object(Object
*);
2769 // Start processing an archive.
2771 archive_start(Archive
*);
2773 // Stop processing an archive.
2775 archive_stop(Archive
*);
2777 // For each dynamic object, check whether we've seen all of its
2778 // explicit dependencies.
2780 check_dynamic_dependencies() const;
2782 // Return whether an object was found in the system library
2785 found_in_system_library_directory(const Object
*) const;
2787 // Print symbol counts.
2789 print_symbol_counts(const Symbol_table
*) const;
2791 // Print a cross reference table.
2793 print_cref(const Symbol_table
*, FILE*) const;
2795 // Iterate over all regular objects.
2798 relobj_begin() const
2799 { return this->relobj_list_
.begin(); }
2803 { return this->relobj_list_
.end(); }
2805 // Iterate over all dynamic objects.
2808 dynobj_begin() const
2809 { return this->dynobj_list_
.begin(); }
2813 { return this->dynobj_list_
.end(); }
2815 // Return whether we have seen any dynamic objects.
2818 { return !this->dynobj_list_
.empty(); }
2820 // Return the number of non dynamic objects.
2822 number_of_relobjs() const
2823 { return this->relobj_list_
.size(); }
2825 // Return the number of input objects.
2827 number_of_input_objects() const
2828 { return this->relobj_list_
.size() + this->dynobj_list_
.size(); }
2831 Input_objects(const Input_objects
&);
2832 Input_objects
& operator=(const Input_objects
&);
2834 // The list of ordinary objects included in the link.
2835 Relobj_list relobj_list_
;
2836 // The list of dynamic objects included in the link.
2837 Dynobj_list dynobj_list_
;
2838 // SONAMEs that we have seen.
2839 Unordered_set
<std::string
> sonames_
;
2840 // Manage cross-references if requested.
2844 // Some of the information we pass to the relocation routines. We
2845 // group this together to avoid passing a dozen different arguments.
2847 template<int size
, bool big_endian
>
2848 struct Relocate_info
2851 const Symbol_table
* symtab
;
2853 const Layout
* layout
;
2854 // Object being relocated.
2855 Sized_relobj_file
<size
, big_endian
>* object
;
2856 // Section index of relocation section.
2857 unsigned int reloc_shndx
;
2858 // Section header of relocation section.
2859 const unsigned char* reloc_shdr
;
2860 // Section index of section being relocated.
2861 unsigned int data_shndx
;
2862 // Section header of data section.
2863 const unsigned char* data_shdr
;
2865 // Return a string showing the location of a relocation. This is
2866 // only used for error messages.
2868 location(size_t relnum
, off_t reloffset
) const;
2871 // This is used to represent a section in an object and is used as the
2872 // key type for various section maps.
2873 typedef std::pair
<Object
*, unsigned int> Section_id
;
2875 // This is similar to Section_id but is used when the section
2876 // pointers are const.
2877 typedef std::pair
<const Object
*, unsigned int> Const_section_id
;
2879 // The hash value is based on the address of an object in memory during
2880 // linking. It is okay to use this for looking up sections but never use
2881 // this in an unordered container that we want to traverse in a repeatable
2884 struct Section_id_hash
2886 size_t operator()(const Section_id
& loc
) const
2887 { return reinterpret_cast<uintptr_t>(loc
.first
) ^ loc
.second
; }
2890 struct Const_section_id_hash
2892 size_t operator()(const Const_section_id
& loc
) const
2893 { return reinterpret_cast<uintptr_t>(loc
.first
) ^ loc
.second
; }
2896 // Return whether INPUT_FILE contains an ELF object start at file
2897 // offset OFFSET. This sets *START to point to a view of the start of
2898 // the file. It sets *READ_SIZE to the number of bytes in the view.
2901 is_elf_object(Input_file
* input_file
, off_t offset
,
2902 const unsigned char** start
, int* read_size
);
2904 // Return an Object appropriate for the input file. P is BYTES long,
2905 // and holds the ELF header. If PUNCONFIGURED is not NULL, then if
2906 // this sees an object the linker is not configured to support, it
2907 // sets *PUNCONFIGURED to true and returns NULL without giving an
2911 make_elf_object(const std::string
& name
, Input_file
*,
2912 off_t offset
, const unsigned char* p
,
2913 section_offset_type bytes
, bool* punconfigured
);
2915 } // end namespace gold
2917 #endif // !defined(GOLD_OBJECT_H)