1 // object.h -- support for an object file for linking in gold -*- C++ -*-
3 // Copyright 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
4 // Written by Ian Lance Taylor <iant@google.com>.
6 // This file is part of gold.
8 // This program is free software; you can redistribute it and/or modify
9 // it under the terms of the GNU General Public License as published by
10 // the Free Software Foundation; either version 3 of the License, or
11 // (at your option) any later version.
13 // This program is distributed in the hope that it will be useful,
14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 // GNU General Public License for more details.
18 // You should have received a copy of the GNU General Public License
19 // along with this program; if not, write to the Free Software
20 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
21 // MA 02110-1301, USA.
30 #include "elfcpp_file.h"
37 class General_options;
44 class Output_symtab_xindex;
47 class Object_merge_map;
48 class Relocatable_relocs;
51 template<typename Stringpool_char>
52 class Stringpool_template;
54 // Data to pass from read_symbols() to add_symbols().
56 struct Read_symbols_data
59 File_view* section_headers;
61 File_view* section_names;
62 // Size of section name data in bytes.
63 section_size_type section_names_size;
66 // Size of symbol data in bytes.
67 section_size_type symbols_size;
68 // Offset of external symbols within symbol data. This structure
69 // sometimes contains only external symbols, in which case this will
70 // be zero. Sometimes it contains all symbols.
71 section_offset_type external_symbols_offset;
73 File_view* symbol_names;
74 // Size of symbol name data in bytes.
75 section_size_type symbol_names_size;
77 // Version information. This is only used on dynamic objects.
78 // Version symbol data (from SHT_GNU_versym section).
80 section_size_type versym_size;
81 // Version definition data (from SHT_GNU_verdef section).
83 section_size_type verdef_size;
84 unsigned int verdef_info;
85 // Needed version data (from SHT_GNU_verneed section).
87 section_size_type verneed_size;
88 unsigned int verneed_info;
91 // Information used to print error messages.
93 struct Symbol_location_info
95 std::string source_file;
96 std::string enclosing_symbol_name;
100 // Data about a single relocation section. This is read in
101 // read_relocs and processed in scan_relocs.
103 struct Section_relocs
105 // Index of reloc section.
106 unsigned int reloc_shndx;
107 // Index of section that relocs apply to.
108 unsigned int data_shndx;
109 // Contents of reloc section.
111 // Reloc section type.
112 unsigned int sh_type;
113 // Number of reloc entries.
116 Output_section* output_section;
117 // Whether this section has special handling for offsets.
118 bool needs_special_offset_handling;
119 // Whether the data section is allocated (has the SHF_ALLOC flag set).
120 bool is_data_section_allocated;
123 // Relocations in an object file. This is read in read_relocs and
124 // processed in scan_relocs.
126 struct Read_relocs_data
128 typedef std::vector<Section_relocs> Relocs_list;
131 // The local symbols.
132 File_view* local_symbols;
135 // The Xindex class manages section indexes for objects with more than
141 Xindex(int large_shndx_offset)
142 : large_shndx_offset_(large_shndx_offset), symtab_xindex_()
145 // Initialize the symtab_xindex_ array, given the object and the
146 // section index of the symbol table to use.
147 template<int size, bool big_endian>
149 initialize_symtab_xindex(Object*, unsigned int symtab_shndx);
151 // Read in the symtab_xindex_ array, given its section index.
152 // PSHDRS may optionally point to the section headers.
153 template<int size, bool big_endian>
155 read_symtab_xindex(Object*, unsigned int xindex_shndx,
156 const unsigned char* pshdrs);
158 // Symbol SYMNDX in OBJECT has a section of SHN_XINDEX; return the
159 // real section index.
161 sym_xindex_to_shndx(Object* object, unsigned int symndx);
164 // The type of the array giving the real section index for symbols
165 // whose st_shndx field holds SHN_XINDEX.
166 typedef std::vector<unsigned int> Symtab_xindex;
168 // Adjust a section index if necessary. This should only be called
169 // for ordinary section indexes.
171 adjust_shndx(unsigned int shndx)
173 if (shndx >= elfcpp::SHN_LORESERVE)
174 shndx += this->large_shndx_offset_;
178 // Adjust to apply to large section indexes.
179 int large_shndx_offset_;
180 // The data from the SHT_SYMTAB_SHNDX section.
181 Symtab_xindex symtab_xindex_;
184 // Object is an abstract base class which represents either a 32-bit
185 // or a 64-bit input object. This can be a regular object file
186 // (ET_REL) or a shared object (ET_DYN).
191 // NAME is the name of the object as we would report it to the user
192 // (e.g., libfoo.a(bar.o) if this is in an archive. INPUT_FILE is
193 // used to read the file. OFFSET is the offset within the input
194 // file--0 for a .o or .so file, something else for a .a file.
195 Object(const std::string& name, Input_file* input_file, bool is_dynamic,
197 : name_(name), input_file_(input_file), offset_(offset), shnum_(-1U),
198 is_dynamic_(is_dynamic), target_(NULL), xindex_(NULL), no_export_(false)
199 { input_file->file().add_object(); }
202 { this->input_file_->file().remove_object(); }
204 // Return the name of the object as we would report it to the tuser.
207 { return this->name_; }
209 // Get the offset into the file.
212 { return this->offset_; }
214 // Return whether this is a dynamic object.
217 { return this->is_dynamic_; }
219 // Returns NULL for Objects that are not plugin objects. This method
220 // is overridden in the Pluginobj class.
223 { return this->do_pluginobj(); }
225 // Return the target structure associated with this object.
228 { return this->target_; }
230 // Get the file. We pass on const-ness.
233 { return this->input_file_; }
237 { return this->input_file_; }
239 // Lock the underlying file.
242 { this->input_file()->file().lock(t); }
244 // Unlock the underlying file.
246 unlock(const Task* t)
247 { this->input_file()->file().unlock(t); }
249 // Return whether the underlying file is locked.
252 { return this->input_file()->file().is_locked(); }
254 // Return the token, so that the task can be queued.
257 { return this->input_file()->file().token(); }
259 // Release the underlying file.
262 { this->input_file_->file().release(); }
264 // Return whether we should just read symbols from this file.
267 { return this->input_file()->just_symbols(); }
269 // Return the sized target structure associated with this object.
270 // This is like the target method but it returns a pointer of
271 // appropriate checked type.
272 template<int size, bool big_endian>
273 Sized_target<size, big_endian>*
274 sized_target() const;
276 // Get the number of sections.
279 { return this->shnum_; }
281 // Return a view of the contents of a section. Set *PLEN to the
282 // size. CACHE is a hint as in File_read::get_view.
284 section_contents(unsigned int shndx, section_size_type* plen, bool cache);
286 // Adjust a symbol's section index as needed. SYMNDX is the index
287 // of the symbol and SHNDX is the symbol's section from
288 // get_st_shndx. This returns the section index. It sets
289 // *IS_ORDINARY to indicate whether this is a normal section index,
290 // rather than a special code between SHN_LORESERVE and
293 adjust_sym_shndx(unsigned int symndx, unsigned int shndx, bool* is_ordinary)
295 if (shndx < elfcpp::SHN_LORESERVE)
297 else if (shndx == elfcpp::SHN_XINDEX)
299 if (this->xindex_ == NULL)
300 this->xindex_ = this->do_initialize_xindex();
301 shndx = this->xindex_->sym_xindex_to_shndx(this, symndx);
305 *is_ordinary = false;
309 // Return the size of a section given a section index.
311 section_size(unsigned int shndx)
312 { return this->do_section_size(shndx); }
314 // Return the name of a section given a section index.
316 section_name(unsigned int shndx)
317 { return this->do_section_name(shndx); }
319 // Return the section flags given a section index.
321 section_flags(unsigned int shndx)
322 { return this->do_section_flags(shndx); }
324 // Return the section address given a section index.
326 section_address(unsigned int shndx)
327 { return this->do_section_address(shndx); }
329 // Return the section type given a section index.
331 section_type(unsigned int shndx)
332 { return this->do_section_type(shndx); }
334 // Return the section link field given a section index.
336 section_link(unsigned int shndx)
337 { return this->do_section_link(shndx); }
339 // Return the section info field given a section index.
341 section_info(unsigned int shndx)
342 { return this->do_section_info(shndx); }
344 // Return the required section alignment given a section index.
346 section_addralign(unsigned int shndx)
347 { return this->do_section_addralign(shndx); }
349 // Read the symbol information.
351 read_symbols(Read_symbols_data* sd)
352 { return this->do_read_symbols(sd); }
354 // Pass sections which should be included in the link to the Layout
355 // object, and record where the sections go in the output file.
357 layout(Symbol_table* symtab, Layout* layout, Read_symbols_data* sd)
358 { this->do_layout(symtab, layout, sd); }
360 // Add symbol information to the global symbol table.
362 add_symbols(Symbol_table* symtab, Read_symbols_data* sd, Layout *layout)
363 { this->do_add_symbols(symtab, sd, layout); }
365 // Functions and types for the elfcpp::Elf_file interface. This
366 // permit us to use Object as the File template parameter for
369 // The View class is returned by view. It must support a single
370 // method, data(). This is trivial, because get_view does what we
375 View(const unsigned char* p)
384 const unsigned char* p_;
389 view(off_t file_offset, section_size_type data_size)
390 { return View(this->get_view(file_offset, data_size, true, true)); }
394 error(const char* format, ...) const ATTRIBUTE_PRINTF_2;
396 // A location in the file.
402 Location(off_t fo, section_size_type ds)
403 : file_offset(fo), data_size(ds)
407 // Get a View given a Location.
408 View view(Location loc)
409 { return View(this->get_view(loc.file_offset, loc.data_size, true, true)); }
411 // Get a view into the underlying file.
413 get_view(off_t start, section_size_type size, bool aligned, bool cache)
415 return this->input_file()->file().get_view(this->offset_, start, size,
419 // Get a lasting view into the underlying file.
421 get_lasting_view(off_t start, section_size_type size, bool aligned,
424 return this->input_file()->file().get_lasting_view(this->offset_, start,
425 size, aligned, cache);
428 // Read data from the underlying file.
430 read(off_t start, section_size_type size, void* p)
431 { this->input_file()->file().read(start + this->offset_, size, p); }
433 // Read multiple data from the underlying file.
435 read_multiple(const File_read::Read_multiple& rm)
436 { this->input_file()->file().read_multiple(this->offset_, rm); }
438 // Stop caching views in the underlying file.
440 clear_view_cache_marks()
441 { this->input_file()->file().clear_view_cache_marks(); }
443 // Get the number of global symbols defined by this object, and the
444 // number of the symbols whose final definition came from this
447 get_global_symbol_counts(const Symbol_table* symtab, size_t* defined,
449 { this->do_get_global_symbol_counts(symtab, defined, used); }
453 set_target(Target* target)
454 { this->target_ = target; }
456 // Return whether this object was found in a system directory.
458 is_in_system_directory() const
459 { return this->input_file()->is_in_system_directory(); }
461 // Return whether we found this object by searching a directory.
464 { return this->input_file()->will_search_for(); }
468 { return this->no_export_; }
471 set_no_export(bool value)
472 { this->no_export_ = value; }
475 // Returns NULL for Objects that are not plugin objects. This method
476 // is overridden in the Pluginobj class.
481 // Read the symbols--implemented by child class.
483 do_read_symbols(Read_symbols_data*) = 0;
485 // Lay out sections--implemented by child class.
487 do_layout(Symbol_table*, Layout*, Read_symbols_data*) = 0;
489 // Add symbol information to the global symbol table--implemented by
492 do_add_symbols(Symbol_table*, Read_symbols_data*, Layout*) = 0;
494 // Return the location of the contents of a section. Implemented by
497 do_section_contents(unsigned int shndx) = 0;
499 // Get the size of a section--implemented by child class.
501 do_section_size(unsigned int shndx) = 0;
503 // Get the name of a section--implemented by child class.
505 do_section_name(unsigned int shndx) = 0;
507 // Get section flags--implemented by child class.
509 do_section_flags(unsigned int shndx) = 0;
511 // Get section address--implemented by child class.
513 do_section_address(unsigned int shndx) = 0;
515 // Get section type--implemented by child class.
517 do_section_type(unsigned int shndx) = 0;
519 // Get section link field--implemented by child class.
521 do_section_link(unsigned int shndx) = 0;
523 // Get section info field--implemented by child class.
525 do_section_info(unsigned int shndx) = 0;
527 // Get section alignment--implemented by child class.
529 do_section_addralign(unsigned int shndx) = 0;
531 // Return the Xindex structure to use.
533 do_initialize_xindex() = 0;
535 // Implement get_global_symbol_counts--implemented by child class.
537 do_get_global_symbol_counts(const Symbol_table*, size_t*, size_t*) const = 0;
541 set_target(int machine, int size, bool big_endian, int osabi,
544 // Set the number of sections.
547 { this->shnum_ = shnum; }
549 // Functions used by both Sized_relobj and Sized_dynobj.
551 // Read the section data into a Read_symbols_data object.
552 template<int size, bool big_endian>
554 read_section_data(elfcpp::Elf_file<size, big_endian, Object>*,
557 // Let the child class initialize the xindex object directly.
559 set_xindex(Xindex* xindex)
561 gold_assert(this->xindex_ == NULL);
562 this->xindex_ = xindex;
565 // If NAME is the name of a special .gnu.warning section, arrange
566 // for the warning to be issued. SHNDX is the section index.
567 // Return whether it is a warning section.
569 handle_gnu_warning_section(const char* name, unsigned int shndx,
573 // This class may not be copied.
574 Object(const Object&);
575 Object& operator=(const Object&);
577 // Name of object as printed to user.
579 // For reading the file.
580 Input_file* input_file_;
581 // Offset within the file--0 for an object file, non-0 for an
584 // Number of input sections.
586 // Whether this is a dynamic object.
588 // Target functions--may be NULL if the target is not known.
590 // Many sections for objects with more than SHN_LORESERVE sections.
592 // True if exclude this object from automatic symbol export.
593 // This is used only for archive objects.
597 // Implement sized_target inline for efficiency. This approach breaks
598 // static type checking, but is made safe using asserts.
600 template<int size, bool big_endian>
601 inline Sized_target<size, big_endian>*
602 Object::sized_target() const
604 gold_assert(this->target_->get_size() == size);
605 gold_assert(this->target_->is_big_endian() ? big_endian : !big_endian);
606 return static_cast<Sized_target<size, big_endian>*>(this->target_);
609 // A regular object (ET_REL). This is an abstract base class itself.
610 // The implementation is the template class Sized_relobj.
612 class Relobj : public Object
615 Relobj(const std::string& name, Input_file* input_file, off_t offset = 0)
616 : Object(name, input_file, false, offset),
618 map_to_relocatable_relocs_(NULL),
619 object_merge_map_(NULL),
620 relocs_must_follow_section_writes_(false)
623 // During garbage collection, the Read_symbols_data pass for
624 // each object is stored as layout needs to be done after
628 { return this->sd_; }
630 // Decides which section names have to be included in the worklist
633 is_section_name_included(const char *name);
636 copy_symbols_data(Symbols_data* gc_sd, Read_symbols_data* sd,
637 unsigned int section_header_size);
640 set_symbols_data(Symbols_data* sd)
643 // During garbage collection, the Read_relocs pass for all objects
644 // is done before scanning the relocs. In that case, this->rd_ is
645 // used to store the information from Read_relocs for each object.
646 // This data is also used to compute the list of relevant sections.
649 { return this->rd_; }
652 set_relocs_data(Read_relocs_data* rd)
656 is_output_section_offset_invalid(unsigned int shndx) const = 0;
660 read_relocs(Read_relocs_data* rd)
661 { return this->do_read_relocs(rd); }
663 // Process the relocs, during garbage collection only.
665 gc_process_relocs(const General_options& options, Symbol_table* symtab,
666 Layout* layout, Read_relocs_data* rd)
667 { return this->do_gc_process_relocs(options, symtab, layout, rd); }
669 // Scan the relocs and adjust the symbol table.
671 scan_relocs(const General_options& options, Symbol_table* symtab,
672 Layout* layout, Read_relocs_data* rd)
673 { return this->do_scan_relocs(options, symtab, layout, rd); }
675 // The number of local symbols in the input symbol table.
677 local_symbol_count() const
678 { return this->do_local_symbol_count(); }
680 // Initial local symbol processing: count the number of local symbols
681 // in the output symbol table and dynamic symbol table; add local symbol
682 // names to *POOL and *DYNPOOL.
684 count_local_symbols(Stringpool_template<char>* pool,
685 Stringpool_template<char>* dynpool)
686 { return this->do_count_local_symbols(pool, dynpool); }
688 // Set the values of the local symbols, set the output symbol table
689 // indexes for the local variables, and set the offset where local
690 // symbol information will be stored. Returns the new local symbol index.
692 finalize_local_symbols(unsigned int index, off_t off)
693 { return this->do_finalize_local_symbols(index, off); }
695 // Set the output dynamic symbol table indexes for the local variables.
697 set_local_dynsym_indexes(unsigned int index)
698 { return this->do_set_local_dynsym_indexes(index); }
700 // Set the offset where local dynamic symbol information will be stored.
702 set_local_dynsym_offset(off_t off)
703 { return this->do_set_local_dynsym_offset(off); }
705 // Relocate the input sections and write out the local symbols.
707 relocate(const General_options& options, const Symbol_table* symtab,
708 const Layout* layout, Output_file* of)
709 { return this->do_relocate(options, symtab, layout, of); }
711 // Return whether an input section is being included in the link.
713 is_section_included(unsigned int shndx) const
715 gold_assert(shndx < this->output_sections_.size());
716 return this->output_sections_[shndx] != NULL;
719 // Given a section index, return the corresponding Output_section.
720 // The return value will be NULL if the section is not included in
723 output_section(unsigned int shndx) const
725 gold_assert(shndx < this->output_sections_.size());
726 return this->output_sections_[shndx];
729 // Given a section index, return the offset in the Output_section.
730 // The return value will be -1U if the section is specially mapped,
731 // such as a merge section.
733 output_section_offset(unsigned int shndx) const
734 { return this->do_output_section_offset(shndx); }
736 // Set the offset of an input section within its output section.
738 set_section_offset(unsigned int shndx, uint64_t off)
739 { this->do_set_section_offset(shndx, off); }
741 // Return true if we need to wait for output sections to be written
742 // before we can apply relocations. This is true if the object has
743 // any relocations for sections which require special handling, such
744 // as the exception frame section.
746 relocs_must_follow_section_writes() const
747 { return this->relocs_must_follow_section_writes_; }
749 // Return the object merge map.
752 { return this->object_merge_map_; }
754 // Set the object merge map.
756 set_merge_map(Object_merge_map* object_merge_map)
758 gold_assert(this->object_merge_map_ == NULL);
759 this->object_merge_map_ = object_merge_map;
762 // Record the relocatable reloc info for an input reloc section.
764 set_relocatable_relocs(unsigned int reloc_shndx, Relocatable_relocs* rr)
766 gold_assert(reloc_shndx < this->shnum());
767 (*this->map_to_relocatable_relocs_)[reloc_shndx] = rr;
770 // Get the relocatable reloc info for an input reloc section.
772 relocatable_relocs(unsigned int reloc_shndx)
774 gold_assert(reloc_shndx < this->shnum());
775 return (*this->map_to_relocatable_relocs_)[reloc_shndx];
778 // Layout sections whose layout was deferred while waiting for
779 // input files from a plugin.
781 layout_deferred_sections(Layout* layout)
782 { this->do_layout_deferred_sections(layout); }
785 // The output section to be used for each input section, indexed by
786 // the input section number. The output section is NULL if the
787 // input section is to be discarded.
788 typedef std::vector<Output_section*> Output_sections;
790 // Read the relocs--implemented by child class.
792 do_read_relocs(Read_relocs_data*) = 0;
794 // Process the relocs--implemented by child class.
796 do_gc_process_relocs(const General_options&, Symbol_table*, Layout*,
797 Read_relocs_data*) = 0;
799 // Scan the relocs--implemented by child class.
801 do_scan_relocs(const General_options&, Symbol_table*, Layout*,
802 Read_relocs_data*) = 0;
804 // Return the number of local symbols--implemented by child class.
806 do_local_symbol_count() const = 0;
808 // Count local symbols--implemented by child class.
810 do_count_local_symbols(Stringpool_template<char>*,
811 Stringpool_template<char>*) = 0;
813 // Finalize the local symbols. Set the output symbol table indexes
814 // for the local variables, and set the offset where local symbol
815 // information will be stored.
817 do_finalize_local_symbols(unsigned int, off_t) = 0;
819 // Set the output dynamic symbol table indexes for the local variables.
821 do_set_local_dynsym_indexes(unsigned int) = 0;
823 // Set the offset where local dynamic symbol information will be stored.
825 do_set_local_dynsym_offset(off_t) = 0;
827 // Relocate the input sections and write out the local
828 // symbols--implemented by child class.
830 do_relocate(const General_options& options, const Symbol_table* symtab,
831 const Layout*, Output_file* of) = 0;
833 // Get the offset of a section--implemented by child class.
835 do_output_section_offset(unsigned int shndx) const = 0;
837 // Set the offset of a section--implemented by child class.
839 do_set_section_offset(unsigned int shndx, uint64_t off) = 0;
841 // Layout sections whose layout was deferred while waiting for
842 // input files from a plugin--implemented by child class.
844 do_layout_deferred_sections(Layout*) = 0;
846 // Return the vector mapping input sections to output sections.
849 { return this->output_sections_; }
851 const Output_sections&
852 output_sections() const
853 { return this->output_sections_; }
855 // Set the size of the relocatable relocs array.
857 size_relocatable_relocs()
859 this->map_to_relocatable_relocs_ =
860 new std::vector<Relocatable_relocs*>(this->shnum());
863 // Record that we must wait for the output sections to be written
864 // before applying relocations.
866 set_relocs_must_follow_section_writes()
867 { this->relocs_must_follow_section_writes_ = true; }
870 // Mapping from input sections to output section.
871 Output_sections output_sections_;
872 // Mapping from input section index to the information recorded for
873 // the relocations. This is only used for a relocatable link.
874 std::vector<Relocatable_relocs*>* map_to_relocatable_relocs_;
875 // Mappings for merge sections. This is managed by the code in the
877 Object_merge_map* object_merge_map_;
878 // Whether we need to wait for output sections to be written before
879 // we can apply relocations.
880 bool relocs_must_follow_section_writes_;
881 // Used to store the relocs data computed by the Read_relocs pass.
882 // Used during garbage collection of unused sections.
883 Read_relocs_data* rd_;
884 // Used to store the symbols data computed by the Read_symbols pass.
885 // Again used during garbage collection when laying out referenced
887 gold::Symbols_data *sd_;
890 // This class is used to handle relocations against a section symbol
891 // in an SHF_MERGE section. For such a symbol, we need to know the
892 // addend of the relocation before we can determine the final value.
893 // The addend gives us the location in the input section, and we can
894 // determine how it is mapped to the output section. For a
895 // non-section symbol, we apply the addend to the final value of the
896 // symbol; that is done in finalize_local_symbols, and does not use
900 class Merged_symbol_value
903 typedef typename elfcpp::Elf_types<size>::Elf_Addr Value;
905 // We use a hash table to map offsets in the input section to output
907 typedef Unordered_map<section_offset_type, Value> Output_addresses;
909 Merged_symbol_value(Value input_value, Value output_start_address)
910 : input_value_(input_value), output_start_address_(output_start_address),
914 // Initialize the hash table.
916 initialize_input_to_output_map(const Relobj*, unsigned int input_shndx);
918 // Release the hash table to save space.
920 free_input_to_output_map()
921 { this->output_addresses_.clear(); }
923 // Get the output value corresponding to an addend. The object and
924 // input section index are passed in because the caller will have
925 // them; otherwise we could store them here.
927 value(const Relobj* object, unsigned int input_shndx, Value addend) const
929 // This is a relocation against a section symbol. ADDEND is the
930 // offset in the section. The result should be the start of some
931 // merge area. If the object file wants something else, it should
932 // use a regular symbol rather than a section symbol.
933 // Unfortunately, PR 6658 shows a case in which the object file
934 // refers to the section symbol, but uses a negative ADDEND to
935 // compensate for a PC relative reloc. We can't handle the
936 // general case. However, we can handle the special case of a
937 // negative addend, by assuming that it refers to the start of the
938 // section. Of course, that means that we have to guess when
939 // ADDEND is negative. It is normal to see a 32-bit value here
940 // even when the template parameter size is 64, as 64-bit object
941 // file formats have 32-bit relocations. We know this is a merge
942 // section, so we know it has to fit into memory. So we assume
943 // that we won't see a value larger than a large 32-bit unsigned
944 // value. This will break objects with very very large merge
945 // sections; they probably break in other ways anyhow.
946 Value input_offset = this->input_value_;
947 if (addend < 0xffffff00)
949 input_offset += addend;
952 typename Output_addresses::const_iterator p =
953 this->output_addresses_.find(input_offset);
954 if (p != this->output_addresses_.end())
955 return p->second + addend;
957 return (this->value_from_output_section(object, input_shndx, input_offset)
962 // Get the output value for an input offset if we couldn't find it
963 // in the hash table.
965 value_from_output_section(const Relobj*, unsigned int input_shndx,
966 Value input_offset) const;
968 // The value of the section symbol in the input file. This is
969 // normally zero, but could in principle be something else.
971 // The start address of this merged section in the output file.
972 Value output_start_address_;
973 // A hash table which maps offsets in the input section to output
974 // addresses. This only maps specific offsets, not all offsets.
975 Output_addresses output_addresses_;
978 // This POD class is holds the value of a symbol. This is used for
979 // local symbols, and for all symbols during relocation processing.
980 // For special sections, such as SHF_MERGE sections, this calls a
981 // function to get the final symbol value.
987 typedef typename elfcpp::Elf_types<size>::Elf_Addr Value;
990 : output_symtab_index_(0), output_dynsym_index_(-1U), input_shndx_(0),
991 is_ordinary_shndx_(false), is_section_symbol_(false),
992 is_tls_symbol_(false), has_output_value_(true)
993 { this->u_.value = 0; }
995 // Get the value of this symbol. OBJECT is the object in which this
996 // symbol is defined, and ADDEND is an addend to add to the value.
997 template<bool big_endian>
999 value(const Sized_relobj<size, big_endian>* object, Value addend) const
1001 if (this->has_output_value_)
1002 return this->u_.value + addend;
1005 gold_assert(this->is_ordinary_shndx_);
1006 return this->u_.merged_symbol_value->value(object, this->input_shndx_,
1011 // Set the value of this symbol in the output symbol table.
1013 set_output_value(Value value)
1014 { this->u_.value = value; }
1016 // For a section symbol in a merged section, we need more
1019 set_merged_symbol_value(Merged_symbol_value<size>* msv)
1021 gold_assert(this->is_section_symbol_);
1022 this->has_output_value_ = false;
1023 this->u_.merged_symbol_value = msv;
1026 // Initialize the input to output map for a section symbol in a
1027 // merged section. We also initialize the value of a non-section
1028 // symbol in a merged section.
1030 initialize_input_to_output_map(const Relobj* object)
1032 if (!this->has_output_value_)
1034 gold_assert(this->is_section_symbol_ && this->is_ordinary_shndx_);
1035 Merged_symbol_value<size>* msv = this->u_.merged_symbol_value;
1036 msv->initialize_input_to_output_map(object, this->input_shndx_);
1040 // Free the input to output map for a section symbol in a merged
1043 free_input_to_output_map()
1045 if (!this->has_output_value_)
1046 this->u_.merged_symbol_value->free_input_to_output_map();
1049 // Set the value of the symbol from the input file. This is only
1050 // called by count_local_symbols, to communicate the value to
1051 // finalize_local_symbols.
1053 set_input_value(Value value)
1054 { this->u_.value = value; }
1056 // Return the input value. This is only called by
1057 // finalize_local_symbols and (in special cases) relocate_section.
1060 { return this->u_.value; }
1062 // Return whether this symbol should go into the output symbol
1065 needs_output_symtab_entry() const
1066 { return this->output_symtab_index_ != -1U; }
1068 // Return the index in the output symbol table.
1070 output_symtab_index() const
1072 gold_assert(this->output_symtab_index_ != 0);
1073 return this->output_symtab_index_;
1076 // Set the index in the output symbol table.
1078 set_output_symtab_index(unsigned int i)
1080 gold_assert(this->output_symtab_index_ == 0);
1081 this->output_symtab_index_ = i;
1084 // Record that this symbol should not go into the output symbol
1087 set_no_output_symtab_entry()
1089 gold_assert(this->output_symtab_index_ == 0);
1090 this->output_symtab_index_ = -1U;
1093 // Set the index in the output dynamic symbol table.
1095 set_needs_output_dynsym_entry()
1097 gold_assert(!this->is_section_symbol());
1098 this->output_dynsym_index_ = 0;
1101 // Return whether this symbol should go into the output symbol
1104 needs_output_dynsym_entry() const
1106 return this->output_dynsym_index_ != -1U;
1109 // Record that this symbol should go into the dynamic symbol table.
1111 set_output_dynsym_index(unsigned int i)
1113 gold_assert(this->output_dynsym_index_ == 0);
1114 this->output_dynsym_index_ = i;
1117 // Return the index in the output dynamic symbol table.
1119 output_dynsym_index() const
1121 gold_assert(this->output_dynsym_index_ != 0
1122 && this->output_dynsym_index_ != -1U);
1123 return this->output_dynsym_index_;
1126 // Set the index of the input section in the input file.
1128 set_input_shndx(unsigned int i, bool is_ordinary)
1130 this->input_shndx_ = i;
1131 // input_shndx_ field is a bitfield, so make sure that the value
1133 gold_assert(this->input_shndx_ == i);
1134 this->is_ordinary_shndx_ = is_ordinary;
1137 // Return the index of the input section in the input file.
1139 input_shndx(bool* is_ordinary) const
1141 *is_ordinary = this->is_ordinary_shndx_;
1142 return this->input_shndx_;
1145 // Whether this is a section symbol.
1147 is_section_symbol() const
1148 { return this->is_section_symbol_; }
1150 // Record that this is a section symbol.
1152 set_is_section_symbol()
1154 gold_assert(!this->needs_output_dynsym_entry());
1155 this->is_section_symbol_ = true;
1158 // Record that this is a TLS symbol.
1161 { this->is_tls_symbol_ = true; }
1163 // Return TRUE if this is a TLS symbol.
1165 is_tls_symbol() const
1166 { return this->is_tls_symbol_; }
1169 // The index of this local symbol in the output symbol table. This
1170 // will be -1 if the symbol should not go into the symbol table.
1171 unsigned int output_symtab_index_;
1172 // The index of this local symbol in the dynamic symbol table. This
1173 // will be -1 if the symbol should not go into the symbol table.
1174 unsigned int output_dynsym_index_;
1175 // The section index in the input file in which this symbol is
1177 unsigned int input_shndx_ : 28;
1178 // Whether the section index is an ordinary index, not a special
1180 bool is_ordinary_shndx_ : 1;
1181 // Whether this is a STT_SECTION symbol.
1182 bool is_section_symbol_ : 1;
1183 // Whether this is a STT_TLS symbol.
1184 bool is_tls_symbol_ : 1;
1185 // Whether this symbol has a value for the output file. This is
1186 // normally set to true during Layout::finalize, by
1187 // finalize_local_symbols. It will be false for a section symbol in
1188 // a merge section, as for such symbols we can not determine the
1189 // value to use in a relocation until we see the addend.
1190 bool has_output_value_ : 1;
1193 // This is used if has_output_value_ is true. Between
1194 // count_local_symbols and finalize_local_symbols, this is the
1195 // value in the input file. After finalize_local_symbols, it is
1196 // the value in the output file.
1198 // This is used if has_output_value_ is false. It points to the
1199 // information we need to get the value for a merge section.
1200 Merged_symbol_value<size>* merged_symbol_value;
1204 // A GOT offset list. A symbol may have more than one GOT offset
1205 // (e.g., when mixing modules compiled with two different TLS models),
1206 // but will usually have at most one. GOT_TYPE identifies the type of
1207 // GOT entry; its values are specific to each target.
1209 class Got_offset_list
1213 : got_type_(-1U), got_offset_(0), got_next_(NULL)
1216 Got_offset_list(unsigned int got_type, unsigned int got_offset)
1217 : got_type_(got_type), got_offset_(got_offset), got_next_(NULL)
1222 if (this->got_next_ != NULL)
1224 delete this->got_next_;
1225 this->got_next_ = NULL;
1229 // Initialize the fields to their default values.
1233 this->got_type_ = -1U;
1234 this->got_offset_ = 0;
1235 this->got_next_ = NULL;
1238 // Set the offset for the GOT entry of type GOT_TYPE.
1240 set_offset(unsigned int got_type, unsigned int got_offset)
1242 if (this->got_type_ == -1U)
1244 this->got_type_ = got_type;
1245 this->got_offset_ = got_offset;
1249 for (Got_offset_list* g = this; g != NULL; g = g->got_next_)
1251 if (g->got_type_ == got_type)
1253 g->got_offset_ = got_offset;
1257 Got_offset_list* g = new Got_offset_list(got_type, got_offset);
1258 g->got_next_ = this->got_next_;
1259 this->got_next_ = g;
1263 // Return the offset for a GOT entry of type GOT_TYPE.
1265 get_offset(unsigned int got_type) const
1267 for (const Got_offset_list* g = this; g != NULL; g = g->got_next_)
1269 if (g->got_type_ == got_type)
1270 return g->got_offset_;
1276 unsigned int got_type_;
1277 unsigned int got_offset_;
1278 Got_offset_list* got_next_;
1281 // A regular object file. This is size and endian specific.
1283 template<int size, bool big_endian>
1284 class Sized_relobj : public Relobj
1287 typedef typename elfcpp::Elf_types<size>::Elf_Addr Address;
1288 typedef std::vector<Symbol*> Symbols;
1289 typedef std::vector<Symbol_value<size> > Local_values;
1291 static const Address invalid_address = static_cast<Address>(0) - 1;
1293 Sized_relobj(const std::string& name, Input_file* input_file, off_t offset,
1294 const typename elfcpp::Ehdr<size, big_endian>&);
1298 // Checks if the offset of input section SHNDX within its output
1299 // section is invalid.
1301 is_output_section_offset_invalid(unsigned int shndx) const
1302 { return this->get_output_section_offset(shndx) == invalid_address; }
1304 // Set up the object file based on the ELF header.
1306 setup(const typename elfcpp::Ehdr<size, big_endian>&);
1308 // Return the number of symbols. This is only valid after
1309 // Object::add_symbols has been called.
1311 symbol_count() const
1312 { return this->local_symbol_count_ + this->symbols_.size(); }
1314 // If SYM is the index of a global symbol in the object file's
1315 // symbol table, return the Symbol object. Otherwise, return NULL.
1317 global_symbol(unsigned int sym) const
1319 if (sym >= this->local_symbol_count_)
1321 gold_assert(sym - this->local_symbol_count_ < this->symbols_.size());
1322 return this->symbols_[sym - this->local_symbol_count_];
1327 // Return the section index of symbol SYM. Set *VALUE to its value
1328 // in the object file. Set *IS_ORDINARY if this is an ordinary
1329 // section index, not a special code between SHN_LORESERVE and
1330 // SHN_HIRESERVE. Note that for a symbol which is not defined in
1331 // this object file, this will set *VALUE to 0 and return SHN_UNDEF;
1332 // it will not return the final value of the symbol in the link.
1334 symbol_section_and_value(unsigned int sym, Address* value, bool* is_ordinary);
1336 // Return a pointer to the Symbol_value structure which holds the
1337 // value of a local symbol.
1338 const Symbol_value<size>*
1339 local_symbol(unsigned int sym) const
1341 gold_assert(sym < this->local_values_.size());
1342 return &this->local_values_[sym];
1345 // Return the index of local symbol SYM in the ordinary symbol
1346 // table. A value of -1U means that the symbol is not being output.
1348 symtab_index(unsigned int sym) const
1350 gold_assert(sym < this->local_values_.size());
1351 return this->local_values_[sym].output_symtab_index();
1354 // Return the index of local symbol SYM in the dynamic symbol
1355 // table. A value of -1U means that the symbol is not being output.
1357 dynsym_index(unsigned int sym) const
1359 gold_assert(sym < this->local_values_.size());
1360 return this->local_values_[sym].output_dynsym_index();
1363 // Return the input section index of local symbol SYM.
1365 local_symbol_input_shndx(unsigned int sym, bool* is_ordinary) const
1367 gold_assert(sym < this->local_values_.size());
1368 return this->local_values_[sym].input_shndx(is_ordinary);
1371 // Return the appropriate Sized_target structure.
1372 Sized_target<size, big_endian>*
1374 { return this->Object::sized_target<size, big_endian>(); }
1376 // Record that local symbol SYM needs a dynamic symbol entry.
1378 set_needs_output_dynsym_entry(unsigned int sym)
1380 gold_assert(sym < this->local_values_.size());
1381 this->local_values_[sym].set_needs_output_dynsym_entry();
1384 // Return whether the local symbol SYMNDX has a GOT offset.
1385 // For TLS symbols, the GOT entry will hold its tp-relative offset.
1387 local_has_got_offset(unsigned int symndx, unsigned int got_type) const
1389 Local_got_offsets::const_iterator p =
1390 this->local_got_offsets_.find(symndx);
1391 return (p != this->local_got_offsets_.end()
1392 && p->second->get_offset(got_type) != -1U);
1395 // Return the GOT offset of the local symbol SYMNDX.
1397 local_got_offset(unsigned int symndx, unsigned int got_type) const
1399 Local_got_offsets::const_iterator p =
1400 this->local_got_offsets_.find(symndx);
1401 gold_assert(p != this->local_got_offsets_.end());
1402 unsigned int off = p->second->get_offset(got_type);
1403 gold_assert(off != -1U);
1407 // Set the GOT offset of the local symbol SYMNDX to GOT_OFFSET.
1409 set_local_got_offset(unsigned int symndx, unsigned int got_type,
1410 unsigned int got_offset)
1412 Local_got_offsets::const_iterator p =
1413 this->local_got_offsets_.find(symndx);
1414 if (p != this->local_got_offsets_.end())
1415 p->second->set_offset(got_type, got_offset);
1418 Got_offset_list* g = new Got_offset_list(got_type, got_offset);
1419 std::pair<Local_got_offsets::iterator, bool> ins =
1420 this->local_got_offsets_.insert(std::make_pair(symndx, g));
1421 gold_assert(ins.second);
1425 // Get the offset of input section SHNDX within its output section.
1426 // This is -1 if the input section requires a special mapping, such
1427 // as a merge section. The output section can be found in the
1428 // output_sections_ field of the parent class Relobj.
1430 get_output_section_offset(unsigned int shndx) const
1432 gold_assert(shndx < this->section_offsets_.size());
1433 return this->section_offsets_[shndx];
1436 // Return the name of the symbol that spans the given offset in the
1437 // specified section in this object. This is used only for error
1438 // messages and is not particularly efficient.
1440 get_symbol_location_info(unsigned int shndx, off_t offset,
1441 Symbol_location_info* info);
1443 // Look for a kept section corresponding to the given discarded section,
1444 // and return its output address. This is used only for relocations in
1445 // debugging sections.
1447 map_to_kept_section(unsigned int shndx, bool* found) const;
1450 // Read the symbols.
1452 do_read_symbols(Read_symbols_data*);
1454 // Return the number of local symbols.
1456 do_local_symbol_count() const
1457 { return this->local_symbol_count_; }
1459 // Lay out the input sections.
1461 do_layout(Symbol_table*, Layout*, Read_symbols_data*);
1463 // Layout sections whose layout was deferred while waiting for
1464 // input files from a plugin.
1466 do_layout_deferred_sections(Layout*);
1468 // Add the symbols to the symbol table.
1470 do_add_symbols(Symbol_table*, Read_symbols_data*, Layout*);
1474 do_read_relocs(Read_relocs_data*);
1476 // Process the relocs to find list of referenced sections. Used only
1477 // during garbage collection.
1479 do_gc_process_relocs(const General_options&, Symbol_table*, Layout*,
1482 // Scan the relocs and adjust the symbol table.
1484 do_scan_relocs(const General_options&, Symbol_table*, Layout*,
1487 // Count the local symbols.
1489 do_count_local_symbols(Stringpool_template<char>*,
1490 Stringpool_template<char>*);
1492 // Finalize the local symbols.
1494 do_finalize_local_symbols(unsigned int, off_t);
1496 // Set the offset where local dynamic symbol information will be stored.
1498 do_set_local_dynsym_indexes(unsigned int);
1500 // Set the offset where local dynamic symbol information will be stored.
1502 do_set_local_dynsym_offset(off_t);
1504 // Relocate the input sections and write out the local symbols.
1506 do_relocate(const General_options& options, const Symbol_table* symtab,
1507 const Layout*, Output_file* of);
1509 // Get the size of a section.
1511 do_section_size(unsigned int shndx)
1512 { return this->elf_file_.section_size(shndx); }
1514 // Get the name of a section.
1516 do_section_name(unsigned int shndx)
1517 { return this->elf_file_.section_name(shndx); }
1519 // Return the location of the contents of a section.
1521 do_section_contents(unsigned int shndx)
1522 { return this->elf_file_.section_contents(shndx); }
1524 // Return section flags.
1526 do_section_flags(unsigned int shndx)
1527 { return this->elf_file_.section_flags(shndx); }
1529 // Return section address.
1531 do_section_address(unsigned int shndx)
1532 { return this->elf_file_.section_addr(shndx); }
1534 // Return section type.
1536 do_section_type(unsigned int shndx)
1537 { return this->elf_file_.section_type(shndx); }
1539 // Return the section link field.
1541 do_section_link(unsigned int shndx)
1542 { return this->elf_file_.section_link(shndx); }
1544 // Return the section info field.
1546 do_section_info(unsigned int shndx)
1547 { return this->elf_file_.section_info(shndx); }
1549 // Return the section alignment.
1551 do_section_addralign(unsigned int shndx)
1552 { return this->elf_file_.section_addralign(shndx); }
1554 // Return the Xindex structure to use.
1556 do_initialize_xindex();
1558 // Get symbol counts.
1560 do_get_global_symbol_counts(const Symbol_table*, size_t*, size_t*) const;
1562 // Get the offset of a section.
1564 do_output_section_offset(unsigned int shndx) const
1566 Address off = this->get_output_section_offset(shndx);
1567 if (off == invalid_address)
1572 // Set the offset of a section.
1574 do_set_section_offset(unsigned int shndx, uint64_t off)
1576 gold_assert(shndx < this->section_offsets_.size());
1577 this->section_offsets_[shndx] = convert_types<Address, uint64_t>(off);
1582 typedef Sized_relobj<size, big_endian> This;
1583 static const int ehdr_size = elfcpp::Elf_sizes<size>::ehdr_size;
1584 static const int shdr_size = elfcpp::Elf_sizes<size>::shdr_size;
1585 static const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
1586 typedef elfcpp::Shdr<size, big_endian> Shdr;
1588 // To keep track of discarded comdat sections, we need to map a member
1589 // section index to the object and section index of the corresponding
1591 struct Kept_comdat_section
1593 Kept_comdat_section(Relobj* a_object, unsigned int a_shndx)
1594 : object(a_object), shndx(a_shndx)
1599 typedef std::map<unsigned int, Kept_comdat_section>
1600 Kept_comdat_section_table;
1602 // Adjust a section index if necessary.
1604 adjust_shndx(unsigned int shndx)
1606 if (shndx >= elfcpp::SHN_LORESERVE)
1607 shndx += this->elf_file_.large_shndx_offset();
1611 // Find the SHT_SYMTAB section, given the section headers.
1613 find_symtab(const unsigned char* pshdrs);
1615 // Return whether SHDR has the right flags for a GNU style exception
1618 check_eh_frame_flags(const elfcpp::Shdr<size, big_endian>* shdr) const;
1620 // Return whether there is a section named .eh_frame which might be
1621 // a GNU style exception frame section.
1623 find_eh_frame(const unsigned char* pshdrs, const char* names,
1624 section_size_type names_size) const;
1626 // Whether to include a section group in the link.
1628 include_section_group(Symbol_table*, Layout*, unsigned int, const char*,
1629 const unsigned char*, const char *, section_size_type,
1630 std::vector<bool>*);
1632 // Whether to include a linkonce section in the link.
1634 include_linkonce_section(Layout*, unsigned int, const char*,
1635 const elfcpp::Shdr<size, big_endian>&);
1637 // Layout an input section.
1639 layout_section(Layout* layout, unsigned int shndx, const char* name,
1640 typename This::Shdr& shdr, unsigned int reloc_shndx,
1641 unsigned int reloc_type);
1643 // Views and sizes when relocating.
1646 unsigned char* view;
1647 typename elfcpp::Elf_types<size>::Elf_Addr address;
1649 section_size_type view_size;
1650 bool is_input_output_view;
1651 bool is_postprocessing_view;
1654 typedef std::vector<View_size> Views;
1656 // Write section data to the output file. Record the views and
1657 // sizes in VIEWS for use when relocating.
1659 write_sections(const unsigned char* pshdrs, Output_file*, Views*);
1661 // Relocate the sections in the output file.
1663 relocate_sections(const General_options& options, const Symbol_table*,
1664 const Layout*, const unsigned char* pshdrs, Views*);
1666 // Scan the input relocations for --emit-relocs.
1668 emit_relocs_scan(const General_options&, Symbol_table*, Layout*,
1669 const unsigned char* plocal_syms,
1670 const Read_relocs_data::Relocs_list::iterator&);
1672 // Scan the input relocations for --emit-relocs, templatized on the
1673 // type of the relocation section.
1674 template<int sh_type>
1676 emit_relocs_scan_reltype(const General_options&, Symbol_table*, Layout*,
1677 const unsigned char* plocal_syms,
1678 const Read_relocs_data::Relocs_list::iterator&,
1679 Relocatable_relocs*);
1681 // Emit the relocs for --emit-relocs.
1683 emit_relocs(const Relocate_info<size, big_endian>*, unsigned int,
1684 unsigned int sh_type, const unsigned char* prelocs,
1685 size_t reloc_count, Output_section*, Address output_offset,
1686 unsigned char* view, Address address,
1687 section_size_type view_size,
1688 unsigned char* reloc_view, section_size_type reloc_view_size);
1690 // Emit the relocs for --emit-relocs, templatized on the type of the
1691 // relocation section.
1692 template<int sh_type>
1694 emit_relocs_reltype(const Relocate_info<size, big_endian>*, unsigned int,
1695 const unsigned char* prelocs, size_t reloc_count,
1696 Output_section*, Address output_offset,
1697 unsigned char* view, Address address,
1698 section_size_type view_size,
1699 unsigned char* reloc_view,
1700 section_size_type reloc_view_size);
1702 // Initialize input to output maps for section symbols in merged
1705 initialize_input_to_output_maps();
1707 // Free the input to output maps for section symbols in merged
1710 free_input_to_output_maps();
1712 // Write out the local symbols.
1714 write_local_symbols(Output_file*,
1715 const Stringpool_template<char>*,
1716 const Stringpool_template<char>*,
1717 Output_symtab_xindex*,
1718 Output_symtab_xindex*);
1720 // Clear the local symbol information.
1722 clear_local_symbols()
1724 this->local_values_.clear();
1725 this->local_got_offsets_.clear();
1728 // Record a mapping from discarded section SHNDX to the corresponding
1731 set_kept_comdat_section(unsigned int shndx, Relobj* kept_object,
1732 unsigned int kept_shndx)
1734 Kept_comdat_section kept(kept_object, kept_shndx);
1735 this->kept_comdat_sections_.insert(std::make_pair(shndx, kept));
1738 // Find the kept section corresponding to the discarded section
1739 // SHNDX. Return true if found.
1741 get_kept_comdat_section(unsigned int shndx, Relobj** kept_object,
1742 unsigned int* kept_shndx) const
1744 typename Kept_comdat_section_table::const_iterator p =
1745 this->kept_comdat_sections_.find(shndx);
1746 if (p == this->kept_comdat_sections_.end())
1748 *kept_object = p->second.object;
1749 *kept_shndx = p->second.shndx;
1753 // The GOT offsets of local symbols. This map also stores GOT offsets
1754 // for tp-relative offsets for TLS symbols.
1755 typedef Unordered_map<unsigned int, Got_offset_list*> Local_got_offsets;
1757 // The TLS GOT offsets of local symbols. The map stores the offsets
1758 // for either a single GOT entry that holds the module index of a TLS
1759 // symbol, or a pair of GOT entries containing the module index and
1760 // dtv-relative offset.
1761 struct Tls_got_entry
1763 Tls_got_entry(int got_offset, bool have_pair)
1764 : got_offset_(got_offset),
1765 have_pair_(have_pair)
1770 typedef Unordered_map<unsigned int, Tls_got_entry> Local_tls_got_offsets;
1772 // Saved information for sections whose layout was deferred.
1773 struct Deferred_layout
1775 static const int shdr_size = elfcpp::Elf_sizes<size>::shdr_size;
1776 Deferred_layout(unsigned int shndx, const char* name,
1777 const unsigned char* pshdr,
1778 unsigned int reloc_shndx, unsigned int reloc_type)
1779 : shndx_(shndx), name_(name), reloc_shndx_(reloc_shndx),
1780 reloc_type_(reloc_type)
1782 memcpy(this->shdr_data_, pshdr, shdr_size);
1784 unsigned int shndx_;
1786 unsigned int reloc_shndx_;
1787 unsigned int reloc_type_;
1788 unsigned char shdr_data_[shdr_size];
1791 // General access to the ELF file.
1792 elfcpp::Elf_file<size, big_endian, Object> elf_file_;
1793 // Index of SHT_SYMTAB section.
1794 unsigned int symtab_shndx_;
1795 // The number of local symbols.
1796 unsigned int local_symbol_count_;
1797 // The number of local symbols which go into the output file.
1798 unsigned int output_local_symbol_count_;
1799 // The number of local symbols which go into the output file's dynamic
1801 unsigned int output_local_dynsym_count_;
1802 // The entries in the symbol table for the external symbols.
1804 // Number of symbols defined in object file itself.
1805 size_t defined_count_;
1806 // File offset for local symbols.
1807 off_t local_symbol_offset_;
1808 // File offset for local dynamic symbols.
1809 off_t local_dynsym_offset_;
1810 // Values of local symbols.
1811 Local_values local_values_;
1812 // GOT offsets for local non-TLS symbols, and tp-relative offsets
1813 // for TLS symbols, indexed by symbol number.
1814 Local_got_offsets local_got_offsets_;
1815 // For each input section, the offset of the input section in its
1816 // output section. This is INVALID_ADDRESS if the input section requires a
1818 std::vector<Address> section_offsets_;
1819 // Table mapping discarded comdat sections to corresponding kept sections.
1820 Kept_comdat_section_table kept_comdat_sections_;
1821 // Whether this object has a GNU style .eh_frame section.
1823 // If this object has a GNU style .eh_frame section that is discarded in
1824 // output, record the index here. Otherwise it is -1U.
1825 unsigned int discarded_eh_frame_shndx_;
1826 // The list of sections whose layout was deferred.
1827 std::vector<Deferred_layout> deferred_layout_;
1830 // A class to manage the list of all objects.
1836 : relobj_list_(), dynobj_list_(), sonames_(), cref_(NULL)
1839 // The type of the list of input relocateable objects.
1840 typedef std::vector<Relobj*> Relobj_list;
1841 typedef Relobj_list::const_iterator Relobj_iterator;
1843 // The type of the list of input dynamic objects.
1844 typedef std::vector<Dynobj*> Dynobj_list;
1845 typedef Dynobj_list::const_iterator Dynobj_iterator;
1847 // Add an object to the list. Return true if all is well, or false
1848 // if this object should be ignored.
1850 add_object(Object*);
1852 // Start processing an archive.
1854 archive_start(Archive*);
1856 // Stop processing an archive.
1858 archive_stop(Archive*);
1860 // For each dynamic object, check whether we've seen all of its
1861 // explicit dependencies.
1863 check_dynamic_dependencies() const;
1865 // Return whether an object was found in the system library
1868 found_in_system_library_directory(const Object*) const;
1870 // Print symbol counts.
1872 print_symbol_counts(const Symbol_table*) const;
1874 // Iterate over all regular objects.
1877 relobj_begin() const
1878 { return this->relobj_list_.begin(); }
1882 { return this->relobj_list_.end(); }
1884 // Iterate over all dynamic objects.
1887 dynobj_begin() const
1888 { return this->dynobj_list_.begin(); }
1892 { return this->dynobj_list_.end(); }
1894 // Return whether we have seen any dynamic objects.
1897 { return !this->dynobj_list_.empty(); }
1899 // Return the number of input objects.
1901 number_of_input_objects() const
1902 { return this->relobj_list_.size() + this->dynobj_list_.size(); }
1905 Input_objects(const Input_objects&);
1906 Input_objects& operator=(const Input_objects&);
1908 // The list of ordinary objects included in the link.
1909 Relobj_list relobj_list_;
1910 // The list of dynamic objects included in the link.
1911 Dynobj_list dynobj_list_;
1912 // SONAMEs that we have seen.
1913 Unordered_set<std::string> sonames_;
1914 // Manage cross-references if requested.
1918 // Some of the information we pass to the relocation routines. We
1919 // group this together to avoid passing a dozen different arguments.
1921 template<int size, bool big_endian>
1922 struct Relocate_info
1924 // Command line options.
1925 const General_options* options;
1927 const Symbol_table* symtab;
1929 const Layout* layout;
1930 // Object being relocated.
1931 Sized_relobj<size, big_endian>* object;
1932 // Section index of relocation section.
1933 unsigned int reloc_shndx;
1934 // Section index of section being relocated.
1935 unsigned int data_shndx;
1937 // Return a string showing the location of a relocation. This is
1938 // only used for error messages.
1940 location(size_t relnum, off_t reloffset) const;
1943 // Return whether INPUT_FILE contains an ELF object start at file
1944 // offset OFFSET. This sets *START to point to a view of the start of
1945 // the file. It sets *READ_SIZE to the number of bytes in the view.
1948 is_elf_object(Input_file* input_file, off_t offset,
1949 const unsigned char** start, int *read_size);
1951 // Return an Object appropriate for the input file. P is BYTES long,
1952 // and holds the ELF header. If PUNCONFIGURED is not NULL, then if
1953 // this sees an object the linker is not configured to support, it
1954 // sets *PUNCONFIGURED to true and returns NULL without giving an
1958 make_elf_object(const std::string& name, Input_file*,
1959 off_t offset, const unsigned char* p,
1960 section_offset_type bytes, bool* punconfigured);
1962 } // end namespace gold
1964 #endif // !defined(GOLD_OBJECT_H)