1 // output.h -- manage the output file for gold -*- C++ -*-
11 #include "reloc-types.h"
16 class General_options;
22 template<int size, bool big_endian>
24 template<int size, bool big_endian>
27 // An abtract class for data which has to go into the output file.
32 explicit Output_data(off_t data_size = 0)
33 : address_(0), data_size_(data_size), offset_(-1)
39 // Return the address. This is only valid after Layout::finalize is
43 { return this->address_; }
45 // Return the size of the data. This must be valid after
46 // Layout::finalize calls set_address, but need not be valid before
50 { return this->data_size_; }
52 // Return the file offset. This is only valid after
53 // Layout::finalize is finished.
56 { return this->offset_; }
58 // Return the required alignment.
61 { return this->do_addralign(); }
63 // Return whether this is an Output_section.
66 { return this->do_is_section(); }
68 // Return whether this is an Output_section of the specified type.
70 is_section_type(elfcpp::Elf_Word stt) const
71 { return this->do_is_section_type(stt); }
73 // Return whether this is an Output_section with the specified flag
76 is_section_flag_set(elfcpp::Elf_Xword shf) const
77 { return this->do_is_section_flag_set(shf); }
79 // Return the output section index, if there is an output section.
82 { return this->do_out_shndx(); }
84 // Set the output section index, if this is an output section.
86 set_out_shndx(unsigned int shndx)
87 { this->do_set_out_shndx(shndx); }
89 // Set the address and file offset of this data. This is called
90 // during Layout::finalize.
92 set_address(uint64_t addr, off_t off);
94 // Write the data to the output file. This is called after
95 // Layout::finalize is complete.
97 write(Output_file* file)
98 { this->do_write(file); }
100 // This is called by Layout::finalize to note that all sizes must
104 { Output_data::sizes_are_fixed = true; }
107 // Functions that child classes may or in some cases must implement.
109 // Write the data to the output file.
111 do_write(Output_file*) = 0;
113 // Return the required alignment.
115 do_addralign() const = 0;
117 // Return whether this is an Output_section.
119 do_is_section() const
122 // Return whether this is an Output_section of the specified type.
123 // This only needs to be implement by Output_section.
125 do_is_section_type(elfcpp::Elf_Word) const
128 // Return whether this is an Output_section with the specific flag
129 // set. This only needs to be implemented by Output_section.
131 do_is_section_flag_set(elfcpp::Elf_Xword) const
134 // Return the output section index, if there is an output section.
137 { gold_unreachable(); }
139 // Set the output section index, if this is an output section.
141 do_set_out_shndx(unsigned int)
142 { gold_unreachable(); }
144 // Set the address and file offset of the data. This only needs to
145 // be implemented if the child needs to know. The child class can
146 // set its size in this call.
148 do_set_address(uint64_t, off_t)
151 // Functions that child classes may call.
153 // Set the size of the data.
155 set_data_size(off_t data_size)
157 gold_assert(!Output_data::sizes_are_fixed);
158 this->data_size_ = data_size;
161 // Return default alignment for a size--32 or 64.
163 default_alignment(int size);
166 Output_data(const Output_data&);
167 Output_data& operator=(const Output_data&);
169 // This is used for verification, to make sure that we don't try to
170 // change any sizes after we set the section addresses.
171 static bool sizes_are_fixed;
173 // Memory address in file (not always meaningful).
175 // Size of data in file.
177 // Offset within file.
181 // Output the section headers.
183 class Output_section_headers : public Output_data
186 Output_section_headers(int size,
189 const Layout::Segment_list*,
190 const Layout::Section_list*,
193 // Write the data to the file.
195 do_write(Output_file*);
197 // Return the required alignment.
200 { return Output_data::default_alignment(this->size_); }
203 // Write the data to the file with the right size and endianness.
204 template<int size, bool big_endian>
206 do_sized_write(Output_file*);
210 const Layout* layout_;
211 const Layout::Segment_list* segment_list_;
212 const Layout::Section_list* unattached_section_list_;
213 const Stringpool* secnamepool_;
216 // Output the segment headers.
218 class Output_segment_headers : public Output_data
221 Output_segment_headers(int size, bool big_endian,
222 const Layout::Segment_list& segment_list);
224 // Write the data to the file.
226 do_write(Output_file*);
228 // Return the required alignment.
231 { return Output_data::default_alignment(this->size_); }
234 // Write the data to the file with the right size and endianness.
235 template<int size, bool big_endian>
237 do_sized_write(Output_file*);
241 const Layout::Segment_list& segment_list_;
244 // Output the ELF file header.
246 class Output_file_header : public Output_data
249 Output_file_header(int size,
251 const General_options&,
254 const Output_segment_headers*);
256 // Add information about the section headers. We lay out the ELF
257 // file header before we create the section headers.
258 void set_section_info(const Output_section_headers*,
259 const Output_section* shstrtab);
261 // Write the data to the file.
263 do_write(Output_file*);
265 // Return the required alignment.
268 { return Output_data::default_alignment(this->size_); }
270 // Set the address and offset--we only implement this for error
273 do_set_address(uint64_t, off_t off) const
274 { gold_assert(off == 0); }
277 // Write the data to the file with the right size and endianness.
278 template<int size, bool big_endian>
280 do_sized_write(Output_file*);
284 const General_options& options_;
285 const Target* target_;
286 const Symbol_table* symtab_;
287 const Output_segment_headers* segment_header_;
288 const Output_section_headers* section_header_;
289 const Output_section* shstrtab_;
292 // Output sections are mainly comprised of input sections. However,
293 // there are cases where we have data to write out which is not in an
294 // input section. Output_section_data is used in such cases. This is
295 // an abstract base class.
297 class Output_section_data : public Output_data
300 Output_section_data(off_t data_size, uint64_t addralign)
301 : Output_data(data_size), output_section_(NULL), addralign_(addralign)
304 Output_section_data(uint64_t addralign)
305 : Output_data(0), output_section_(NULL), addralign_(addralign)
308 // Return the output section.
309 const Output_section*
310 output_section() const
311 { return this->output_section_; }
313 // Record the output section.
315 set_output_section(Output_section* os);
317 // Add an input section, for SHF_MERGE sections. This returns true
318 // if the section was handled.
320 add_input_section(Relobj* object, unsigned int shndx)
321 { return this->do_add_input_section(object, shndx); }
323 // Given an input OBJECT, an input section index SHNDX within that
324 // object, and an OFFSET relative to the start of that input
325 // section, return whether or not the output address is known.
326 // OUTPUT_SECTION_ADDRESS is the address of the output section which
327 // this is a part of. If this function returns true, it sets
328 // *POUTPUT to the output address.
330 output_address(const Relobj* object, unsigned int shndx, off_t offset,
331 uint64_t output_section_address, uint64_t *poutput) const
333 return this->do_output_address(object, shndx, offset,
334 output_section_address, poutput);
338 // The child class must implement do_write.
340 // The child class may implement specific adjustments to the output
343 do_adjust_output_section(Output_section*)
346 // May be implemented by child class. Return true if the section
349 do_add_input_section(Relobj*, unsigned int)
350 { gold_unreachable(); }
352 // The child class may implement output_address.
354 do_output_address(const Relobj*, unsigned int, off_t, uint64_t,
358 // Return the required alignment.
361 { return this->addralign_; }
363 // Return the section index of the output section.
365 do_out_shndx() const;
367 // Set the alignment.
369 set_addralign(uint64_t addralign)
370 { this->addralign_ = addralign; }
373 // The output section for this section.
374 const Output_section* output_section_;
375 // The required alignment.
379 // A simple case of Output_data in which we have constant data to
382 class Output_data_const : public Output_section_data
385 Output_data_const(const std::string& data, uint64_t addralign)
386 : Output_section_data(data.size(), addralign), data_(data)
389 Output_data_const(const char* p, off_t len, uint64_t addralign)
390 : Output_section_data(len, addralign), data_(p, len)
393 Output_data_const(const unsigned char* p, off_t len, uint64_t addralign)
394 : Output_section_data(len, addralign),
395 data_(reinterpret_cast<const char*>(p), len)
400 add_data(const std::string& add)
402 this->data_.append(add);
403 this->set_data_size(this->data_.size());
406 // Write the data to the output file.
408 do_write(Output_file*);
414 // Another version of Output_data with constant data, in which the
415 // buffer is allocated by the caller.
417 class Output_data_const_buffer : public Output_section_data
420 Output_data_const_buffer(const unsigned char* p, off_t len,
422 : Output_section_data(len, addralign), p_(p)
425 // Write the data the output file.
427 do_write(Output_file*);
430 const unsigned char* p_;
433 // A place holder for data written out via some other mechanism.
435 class Output_data_space : public Output_section_data
438 Output_data_space(off_t data_size, uint64_t addralign)
439 : Output_section_data(data_size, addralign)
442 explicit Output_data_space(uint64_t addralign)
443 : Output_section_data(addralign)
448 set_space_size(off_t space_size)
449 { this->set_data_size(space_size); }
451 // Set the alignment.
453 set_space_alignment(uint64_t align)
454 { this->set_addralign(align); }
456 // Write out the data--this must be handled elsewhere.
458 do_write(Output_file*)
462 // A string table which goes into an output section.
464 class Output_data_strtab : public Output_section_data
467 Output_data_strtab(Stringpool* strtab)
468 : Output_section_data(1), strtab_(strtab)
471 // This is called to set the address and file offset. Here we make
472 // sure that the Stringpool is finalized.
474 do_set_address(uint64_t, off_t);
476 // Write out the data.
478 do_write(Output_file*);
484 // This POD class is used to represent a single reloc in the output
485 // file. This could be a private class within Output_data_reloc, but
486 // the templatization is complex enough that I broke it out into a
487 // separate class. The class is templatized on either elfcpp::SHT_REL
488 // or elfcpp::SHT_RELA, and also on whether this is a dynamic
489 // relocation or an ordinary relocation.
491 // A relocation can be against a global symbol, a local symbol, an
492 // output section, or the undefined symbol at index 0. We represent
493 // the latter by using a NULL global symbol.
495 template<int sh_type, bool dynamic, int size, bool big_endian>
498 template<bool dynamic, int size, bool big_endian>
499 class Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>
502 typedef typename elfcpp::Elf_types<size>::Elf_Addr Address;
504 // An uninitialized entry. We need this because we want to put
505 // instances of this class into an STL container.
507 : local_sym_index_(INVALID_CODE)
510 // A reloc against a global symbol.
512 Output_reloc(Symbol* gsym, unsigned int type, Output_data* od,
514 : address_(address), local_sym_index_(GSYM_CODE), type_(type),
517 this->u1_.gsym = gsym;
521 Output_reloc(Symbol* gsym, unsigned int type, Relobj* relobj,
522 unsigned int shndx, Address address)
523 : address_(address), local_sym_index_(GSYM_CODE), type_(type),
526 gold_assert(shndx != INVALID_CODE);
527 this->u1_.gsym = gsym;
528 this->u2_.relobj = relobj;
531 // A reloc against a local symbol.
533 Output_reloc(Sized_relobj<size, big_endian>* relobj,
534 unsigned int local_sym_index,
538 : address_(address), local_sym_index_(local_sym_index), type_(type),
541 gold_assert(local_sym_index != GSYM_CODE
542 && local_sym_index != INVALID_CODE);
543 this->u1_.relobj = relobj;
547 Output_reloc(Sized_relobj<size, big_endian>* relobj,
548 unsigned int local_sym_index,
552 : address_(address), local_sym_index_(local_sym_index), type_(type),
555 gold_assert(local_sym_index != GSYM_CODE
556 && local_sym_index != INVALID_CODE);
557 gold_assert(shndx != INVALID_CODE);
558 this->u1_.relobj = relobj;
559 this->u2_.relobj = relobj;
562 // A reloc against the STT_SECTION symbol of an output section.
564 Output_reloc(Output_section* os, unsigned int type, Output_data* od,
566 : address_(address), local_sym_index_(SECTION_CODE), type_(type),
573 Output_reloc(Output_section* os, unsigned int type, Relobj* relobj,
574 unsigned int shndx, Address address)
575 : address_(address), local_sym_index_(SECTION_CODE), type_(type),
578 gold_assert(shndx != INVALID_CODE);
580 this->u2_.relobj = relobj;
583 // Write the reloc entry to an output view.
585 write(unsigned char* pov) const;
587 // Write the offset and info fields to Write_rel.
588 template<typename Write_rel>
589 void write_rel(Write_rel*) const;
592 // Return the symbol index. We can't do a double template
593 // specialization, so we do a secondary template here.
595 get_symbol_index() const;
597 // Codes for local_sym_index_.
604 // Invalid uninitialized entry.
610 // For a local symbol, the object. We will never generate a
611 // relocation against a local symbol in a dynamic object; that
612 // doesn't make sense. And our callers will always be
613 // templatized, so we use Sized_relobj here.
614 Sized_relobj<size, big_endian>* relobj;
615 // For a global symbol, the symbol. If this is NULL, it indicates
616 // a relocation against the undefined 0 symbol.
618 // For a relocation against an output section, the output section.
623 // If shndx_ is not INVALID CODE, the object which holds the input
624 // section being used to specify the reloc address.
626 // If shndx_ is INVALID_CODE, the output data being used to
627 // specify the reloc address. This may be NULL if the reloc
628 // address is absolute.
631 // The address offset within the input section or the Output_data.
633 // For a local symbol, the local symbol index. This is GSYM_CODE
634 // for a global symbol, or INVALID_CODE for an uninitialized value.
635 unsigned int local_sym_index_;
636 // The reloc type--a processor specific code.
638 // If the reloc address is an input section in an object, the
639 // section index. This is INVALID_CODE if the reloc address is
640 // specified in some other way.
644 // The SHT_RELA version of Output_reloc<>. This is just derived from
645 // the SHT_REL version of Output_reloc, but it adds an addend.
647 template<bool dynamic, int size, bool big_endian>
648 class Output_reloc<elfcpp::SHT_RELA, dynamic, size, big_endian>
651 typedef typename elfcpp::Elf_types<size>::Elf_Addr Address;
652 typedef typename elfcpp::Elf_types<size>::Elf_Addr Addend;
654 // An uninitialized entry.
659 // A reloc against a global symbol.
661 Output_reloc(Symbol* gsym, unsigned int type, Output_data* od,
662 Address address, Addend addend)
663 : rel_(gsym, type, od, address), addend_(addend)
666 Output_reloc(Symbol* gsym, unsigned int type, Relobj* relobj,
667 unsigned int shndx, Address address, Addend addend)
668 : rel_(gsym, type, relobj, shndx, address), addend_(addend)
671 // A reloc against a local symbol.
673 Output_reloc(Sized_relobj<size, big_endian>* relobj,
674 unsigned int local_sym_index,
675 unsigned int type, Output_data* od, Address address,
677 : rel_(relobj, local_sym_index, type, od, address), addend_(addend)
680 Output_reloc(Sized_relobj<size, big_endian>* relobj,
681 unsigned int local_sym_index,
686 : rel_(relobj, local_sym_index, type, shndx, address),
690 // A reloc against the STT_SECTION symbol of an output section.
692 Output_reloc(Output_section* os, unsigned int type, Output_data* od,
693 Address address, Addend addend)
694 : rel_(os, type, od, address), addend_(addend)
697 Output_reloc(Output_section* os, unsigned int type, Relobj* relobj,
698 unsigned int shndx, Address address, Addend addend)
699 : rel_(os, type, relobj, shndx, address), addend_(addend)
702 // Write the reloc entry to an output view.
704 write(unsigned char* pov) const;
708 Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian> rel_;
713 // Output_data_reloc is used to manage a section containing relocs.
714 // SH_TYPE is either elfcpp::SHT_REL or elfcpp::SHT_RELA. DYNAMIC
715 // indicates whether this is a dynamic relocation or a normal
716 // relocation. Output_data_reloc_base is a base class.
717 // Output_data_reloc is the real class, which we specialize based on
720 template<int sh_type, bool dynamic, int size, bool big_endian>
721 class Output_data_reloc_base : public Output_section_data
724 typedef Output_reloc<sh_type, dynamic, size, big_endian> Output_reloc_type;
725 typedef typename Output_reloc_type::Address Address;
726 static const int reloc_size =
727 Reloc_types<sh_type, size, big_endian>::reloc_size;
729 // Construct the section.
730 Output_data_reloc_base()
731 : Output_section_data(Output_data::default_alignment(size))
734 // Write out the data.
736 do_write(Output_file*);
739 // Set the entry size and the link.
741 do_adjust_output_section(Output_section *os);
743 // Add a relocation entry.
745 add(const Output_reloc_type& reloc)
747 this->relocs_.push_back(reloc);
748 this->set_data_size(this->relocs_.size() * reloc_size);
752 typedef std::vector<Output_reloc_type> Relocs;
757 // The class which callers actually create.
759 template<int sh_type, bool dynamic, int size, bool big_endian>
760 class Output_data_reloc;
762 // The SHT_REL version of Output_data_reloc.
764 template<bool dynamic, int size, bool big_endian>
765 class Output_data_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>
766 : public Output_data_reloc_base<elfcpp::SHT_REL, dynamic, size, big_endian>
769 typedef Output_data_reloc_base<elfcpp::SHT_REL, dynamic, size,
773 typedef typename Base::Output_reloc_type Output_reloc_type;
774 typedef typename Output_reloc_type::Address Address;
777 : Output_data_reloc_base<elfcpp::SHT_REL, dynamic, size, big_endian>()
780 // Add a reloc against a global symbol.
783 add_global(Symbol* gsym, unsigned int type, Output_data* od, Address address)
784 { this->add(Output_reloc_type(gsym, type, od, address)); }
787 add_global(Symbol* gsym, unsigned int type, Relobj* relobj,
788 unsigned int shndx, Address address)
789 { this->add(Output_reloc_type(gsym, type, relobj, shndx, address)); }
791 // Add a reloc against a local symbol.
794 add_local(Sized_relobj<size, big_endian>* relobj,
795 unsigned int local_sym_index, unsigned int type,
796 Output_data* od, Address address)
797 { this->add(Output_reloc_type(relobj, local_sym_index, type, od, address)); }
800 add_local(Sized_relobj<size, big_endian>* relobj,
801 unsigned int local_sym_index, unsigned int type,
802 unsigned int shndx, Address address)
803 { this->add(Output_reloc_type(relobj, local_sym_index, type, shndx,
807 // A reloc against the STT_SECTION symbol of an output section.
810 add_output_section(Output_section* os, unsigned int type,
811 Output_data* od, Address address)
812 { this->add(Output_reloc_type(os, type, od, address)); }
815 add_output_section(Output_section* os, unsigned int type,
816 Relobj* relobj, unsigned int shndx, Address address)
817 { this->add(Output_reloc_type(os, type, relobj, shndx, address)); }
820 // The SHT_RELA version of Output_data_reloc.
822 template<bool dynamic, int size, bool big_endian>
823 class Output_data_reloc<elfcpp::SHT_RELA, dynamic, size, big_endian>
824 : public Output_data_reloc_base<elfcpp::SHT_RELA, dynamic, size, big_endian>
827 typedef Output_data_reloc_base<elfcpp::SHT_RELA, dynamic, size,
831 typedef typename Base::Output_reloc_type Output_reloc_type;
832 typedef typename Output_reloc_type::Address Address;
833 typedef typename Output_reloc_type::Addend Addend;
836 : Output_data_reloc_base<elfcpp::SHT_RELA, dynamic, size, big_endian>()
839 // Add a reloc against a global symbol.
842 add_global(Symbol* gsym, unsigned int type, Output_data* od,
843 Address address, Addend addend)
844 { this->add(Output_reloc_type(gsym, type, od, address, addend)); }
847 add_global(Symbol* gsym, unsigned int type, Relobj* relobj,
848 unsigned int shndx, Address address, Addend addend)
849 { this->add(Output_reloc_type(gsym, type, relobj, shndx, address, addend)); }
851 // Add a reloc against a local symbol.
854 add_local(Sized_relobj<size, big_endian>* relobj,
855 unsigned int local_sym_index, unsigned int type,
856 Output_data* od, Address address, Addend addend)
858 this->add(Output_reloc_type(relobj, local_sym_index, type, od, address,
863 add_local(Sized_relobj<size, big_endian>* relobj,
864 unsigned int local_sym_index, unsigned int type,
865 unsigned int shndx, Address address, Addend addend)
867 this->add(Output_reloc_type(relobj, local_sym_index, type, shndx, address,
871 // A reloc against the STT_SECTION symbol of an output section.
874 add_output_section(Output_section* os, unsigned int type, Output_data* od,
875 Address address, Addend addend)
876 { this->add(Output_reloc_type(os, type, od, address, addend)); }
879 add_output_section(Output_section* os, unsigned int type, Relobj* relobj,
880 unsigned int shndx, Address address, Addend addend)
881 { this->add(Output_reloc_type(os, type, relobj, shndx, address, addend)); }
884 // Output_data_got is used to manage a GOT. Each entry in the GOT is
885 // for one symbol--either a global symbol or a local symbol in an
886 // object. The target specific code adds entries to the GOT as
889 template<int size, bool big_endian>
890 class Output_data_got : public Output_section_data
893 typedef typename elfcpp::Elf_types<size>::Elf_Addr Valtype;
895 Output_data_got(const General_options* options)
896 : Output_section_data(Output_data::default_alignment(size)),
897 options_(options), entries_()
900 // Add an entry for a global symbol to the GOT. Return true if this
901 // is a new GOT entry, false if the symbol was already in the GOT.
903 add_global(Symbol* gsym);
905 // Add an entry for a local symbol to the GOT. This returns the
906 // offset of the new entry from the start of the GOT.
908 add_local(Object* object, unsigned int sym_index)
910 this->entries_.push_back(Got_entry(object, sym_index));
911 this->set_got_size();
912 return this->last_got_offset();
915 // Add a constant to the GOT. This returns the offset of the new
916 // entry from the start of the GOT.
918 add_constant(Valtype constant)
920 this->entries_.push_back(Got_entry(constant));
921 this->set_got_size();
922 return this->last_got_offset();
925 // Write out the GOT table.
927 do_write(Output_file*);
930 // This POD class holds a single GOT entry.
934 // Create a zero entry.
936 : local_sym_index_(CONSTANT_CODE)
937 { this->u_.constant = 0; }
939 // Create a global symbol entry.
940 explicit Got_entry(Symbol* gsym)
941 : local_sym_index_(GSYM_CODE)
942 { this->u_.gsym = gsym; }
944 // Create a local symbol entry.
945 Got_entry(Object* object, unsigned int local_sym_index)
946 : local_sym_index_(local_sym_index)
948 gold_assert(local_sym_index != GSYM_CODE
949 && local_sym_index != CONSTANT_CODE);
950 this->u_.object = object;
953 // Create a constant entry. The constant is a host value--it will
954 // be swapped, if necessary, when it is written out.
955 explicit Got_entry(Valtype constant)
956 : local_sym_index_(CONSTANT_CODE)
957 { this->u_.constant = constant; }
959 // Write the GOT entry to an output view.
961 write(const General_options*, unsigned char* pov) const;
972 // For a local symbol, the object.
974 // For a global symbol, the symbol.
976 // For a constant, the constant.
979 // For a local symbol, the local symbol index. This is GSYM_CODE
980 // for a global symbol, or CONSTANT_CODE for a constant.
981 unsigned int local_sym_index_;
984 typedef std::vector<Got_entry> Got_entries;
986 // Return the offset into the GOT of GOT entry I.
988 got_offset(unsigned int i) const
989 { return i * (size / 8); }
991 // Return the offset into the GOT of the last entry added.
993 last_got_offset() const
994 { return this->got_offset(this->entries_.size() - 1); }
996 // Set the size of the section.
999 { this->set_data_size(this->got_offset(this->entries_.size())); }
1002 const General_options* options_;
1003 // The list of GOT entries.
1004 Got_entries entries_;
1007 // Output_data_dynamic is used to hold the data in SHT_DYNAMIC
1010 class Output_data_dynamic : public Output_section_data
1013 Output_data_dynamic(const Target* target, Stringpool* pool)
1014 : Output_section_data(Output_data::default_alignment(target->get_size())),
1015 target_(target), entries_(), pool_(pool)
1018 // Add a new dynamic entry with a fixed numeric value.
1020 add_constant(elfcpp::DT tag, unsigned int val)
1021 { this->add_entry(Dynamic_entry(tag, val)); }
1023 // Add a new dynamic entry with the address of output data.
1025 add_section_address(elfcpp::DT tag, const Output_data* od)
1026 { this->add_entry(Dynamic_entry(tag, od, false)); }
1028 // Add a new dynamic entry with the size of output data.
1030 add_section_size(elfcpp::DT tag, const Output_data* od)
1031 { this->add_entry(Dynamic_entry(tag, od, true)); }
1033 // Add a new dynamic entry with the address of a symbol.
1035 add_symbol(elfcpp::DT tag, const Symbol* sym)
1036 { this->add_entry(Dynamic_entry(tag, sym)); }
1038 // Add a new dynamic entry with a string.
1040 add_string(elfcpp::DT tag, const char* str)
1041 { this->add_entry(Dynamic_entry(tag, this->pool_->add(str, NULL))); }
1044 add_string(elfcpp::DT tag, const std::string& str)
1045 { this->add_string(tag, str.c_str()); }
1047 // Set the final data size.
1049 do_set_address(uint64_t, off_t);
1051 // Write out the dynamic entries.
1053 do_write(Output_file*);
1056 // Adjust the output section to set the entry size.
1058 do_adjust_output_section(Output_section*);
1061 // This POD class holds a single dynamic entry.
1065 // Create an entry with a fixed numeric value.
1066 Dynamic_entry(elfcpp::DT tag, unsigned int val)
1067 : tag_(tag), classification_(DYNAMIC_NUMBER)
1068 { this->u_.val = val; }
1070 // Create an entry with the size or address of a section.
1071 Dynamic_entry(elfcpp::DT tag, const Output_data* od, bool section_size)
1073 classification_(section_size
1074 ? DYNAMIC_SECTION_SIZE
1075 : DYNAMIC_SECTION_ADDRESS)
1076 { this->u_.od = od; }
1078 // Create an entry with the address of a symbol.
1079 Dynamic_entry(elfcpp::DT tag, const Symbol* sym)
1080 : tag_(tag), classification_(DYNAMIC_SYMBOL)
1081 { this->u_.sym = sym; }
1083 // Create an entry with a string.
1084 Dynamic_entry(elfcpp::DT tag, const char* str)
1085 : tag_(tag), classification_(DYNAMIC_STRING)
1086 { this->u_.str = str; }
1088 // Write the dynamic entry to an output view.
1089 template<int size, bool big_endian>
1091 write(unsigned char* pov, const Stringpool* ACCEPT_SIZE_ENDIAN) const;
1099 DYNAMIC_SECTION_ADDRESS,
1101 DYNAMIC_SECTION_SIZE,
1110 // For DYNAMIC_NUMBER.
1112 // For DYNAMIC_SECTION_ADDRESS and DYNAMIC_SECTION_SIZE.
1113 const Output_data* od;
1114 // For DYNAMIC_SYMBOL.
1116 // For DYNAMIC_STRING.
1121 // The type of entry.
1122 Classification classification_;
1125 // Add an entry to the list.
1127 add_entry(const Dynamic_entry& entry)
1128 { this->entries_.push_back(entry); }
1130 // Sized version of write function.
1131 template<int size, bool big_endian>
1133 sized_write(Output_file* of);
1135 // The type of the list of entries.
1136 typedef std::vector<Dynamic_entry> Dynamic_entries;
1139 const Target* target_;
1141 Dynamic_entries entries_;
1142 // The pool used for strings.
1146 // An output section. We don't expect to have too many output
1147 // sections, so we don't bother to do a template on the size.
1149 class Output_section : public Output_data
1152 // Create an output section, giving the name, type, and flags.
1153 Output_section(const char* name, elfcpp::Elf_Word, elfcpp::Elf_Xword);
1154 virtual ~Output_section();
1156 // Add a new input section SHNDX, named NAME, with header SHDR, from
1157 // object OBJECT. Return the offset within the output section.
1158 template<int size, bool big_endian>
1160 add_input_section(Relobj* object, unsigned int shndx, const char *name,
1161 const elfcpp::Shdr<size, big_endian>& shdr);
1163 // Add generated data POSD to this output section.
1165 add_output_section_data(Output_section_data* posd);
1167 // Return the section name.
1170 { return this->name_; }
1172 // Return the section type.
1175 { return this->type_; }
1177 // Return the section flags.
1180 { return this->flags_; }
1182 // Return the section index in the output file.
1184 do_out_shndx() const
1185 { return this->out_shndx_; }
1187 // Set the output section index.
1189 do_set_out_shndx(unsigned int shndx)
1190 { this->out_shndx_ = shndx; }
1192 // Return the entsize field.
1195 { return this->entsize_; }
1197 // Set the entsize field.
1199 set_entsize(uint64_t v);
1201 // Set the link field to the output section index of a section.
1203 set_link_section(const Output_data* od)
1205 gold_assert(this->link_ == 0
1206 && !this->should_link_to_symtab_
1207 && !this->should_link_to_dynsym_);
1208 this->link_section_ = od;
1211 // Set the link field to a constant.
1213 set_link(unsigned int v)
1215 gold_assert(this->link_section_ == NULL
1216 && !this->should_link_to_symtab_
1217 && !this->should_link_to_dynsym_);
1221 // Record that this section should link to the normal symbol table.
1223 set_should_link_to_symtab()
1225 gold_assert(this->link_section_ == NULL
1227 && !this->should_link_to_dynsym_);
1228 this->should_link_to_symtab_ = true;
1231 // Record that this section should link to the dynamic symbol table.
1233 set_should_link_to_dynsym()
1235 gold_assert(this->link_section_ == NULL
1237 && !this->should_link_to_symtab_);
1238 this->should_link_to_dynsym_ = true;
1241 // Return the info field.
1245 gold_assert(this->info_section_ == NULL);
1249 // Set the info field to the output section index of a section.
1251 set_info_section(const Output_data* od)
1253 gold_assert(this->info_ == 0);
1254 this->info_section_ = od;
1257 // Set the info field to a constant.
1259 set_info(unsigned int v)
1261 gold_assert(this->info_section_ == NULL);
1265 // Set the addralign field.
1267 set_addralign(uint64_t v)
1268 { this->addralign_ = v; }
1270 // Indicate that we need a symtab index.
1272 set_needs_symtab_index()
1273 { this->needs_symtab_index_ = true; }
1275 // Return whether we need a symtab index.
1277 needs_symtab_index() const
1278 { return this->needs_symtab_index_; }
1280 // Get the symtab index.
1282 symtab_index() const
1284 gold_assert(this->symtab_index_ != 0);
1285 return this->symtab_index_;
1288 // Set the symtab index.
1290 set_symtab_index(unsigned int index)
1292 gold_assert(index != 0);
1293 this->symtab_index_ = index;
1296 // Indicate that we need a dynsym index.
1298 set_needs_dynsym_index()
1299 { this->needs_dynsym_index_ = true; }
1301 // Return whether we need a dynsym index.
1303 needs_dynsym_index() const
1304 { return this->needs_dynsym_index_; }
1306 // Get the dynsym index.
1308 dynsym_index() const
1310 gold_assert(this->dynsym_index_ != 0);
1311 return this->dynsym_index_;
1314 // Set the dynsym index.
1316 set_dynsym_index(unsigned int index)
1318 gold_assert(index != 0);
1319 this->dynsym_index_ = index;
1322 // Return the output virtual address of OFFSET relative to the start
1323 // of input section SHNDX in object OBJECT.
1325 output_address(const Relobj* object, unsigned int shndx,
1326 off_t offset) const;
1328 // Set the address of the Output_section. For a typical
1329 // Output_section, there is nothing to do, but if there are any
1330 // Output_section_data objects we need to set the final addresses
1333 do_set_address(uint64_t, off_t);
1335 // Write the data to the file. For a typical Output_section, this
1336 // does nothing: the data is written out by calling Object::Relocate
1337 // on each input object. But if there are any Output_section_data
1338 // objects we do need to write them out here.
1340 do_write(Output_file*);
1342 // Return the address alignment--function required by parent class.
1344 do_addralign() const
1345 { return this->addralign_; }
1347 // Return whether this is an Output_section.
1349 do_is_section() const
1352 // Return whether this is a section of the specified type.
1354 do_is_section_type(elfcpp::Elf_Word type) const
1355 { return this->type_ == type; }
1357 // Return whether the specified section flag is set.
1359 do_is_section_flag_set(elfcpp::Elf_Xword flag) const
1360 { return (this->flags_ & flag) != 0; }
1362 // Write the section header into *OPHDR.
1363 template<int size, bool big_endian>
1365 write_header(const Layout*, const Stringpool*,
1366 elfcpp::Shdr_write<size, big_endian>*) const;
1369 // In some cases we need to keep a list of the input sections
1370 // associated with this output section. We only need the list if we
1371 // might have to change the offsets of the input section within the
1372 // output section after we add the input section. The ordinary
1373 // input sections will be written out when we process the object
1374 // file, and as such we don't need to track them here. We do need
1375 // to track Output_section_data objects here. We store instances of
1376 // this structure in a std::vector, so it must be a POD. There can
1377 // be many instances of this structure, so we use a union to save
1383 : shndx_(0), p2align_(0)
1385 this->u1_.data_size = 0;
1386 this->u2_.object = NULL;
1389 // For an ordinary input section.
1390 Input_section(Relobj* object, unsigned int shndx, off_t data_size,
1393 p2align_(ffsll(static_cast<long long>(addralign)))
1395 gold_assert(shndx != OUTPUT_SECTION_CODE
1396 && shndx != MERGE_DATA_SECTION_CODE
1397 && shndx != MERGE_STRING_SECTION_CODE);
1398 this->u1_.data_size = data_size;
1399 this->u2_.object = object;
1402 // For a non-merge output section.
1403 Input_section(Output_section_data* posd)
1404 : shndx_(OUTPUT_SECTION_CODE),
1405 p2align_(ffsll(static_cast<long long>(posd->addralign())))
1407 this->u1_.data_size = 0;
1408 this->u2_.posd = posd;
1411 // For a merge section.
1412 Input_section(Output_section_data* posd, bool is_string, uint64_t entsize)
1414 ? MERGE_STRING_SECTION_CODE
1415 : MERGE_DATA_SECTION_CODE),
1416 p2align_(ffsll(static_cast<long long>(posd->addralign())))
1418 this->u1_.entsize = entsize;
1419 this->u2_.posd = posd;
1422 // The required alignment.
1426 return (this->p2align_ == 0
1428 : static_cast<uint64_t>(1) << (this->p2align_ - 1));
1431 // Return the required size.
1435 // Return whether this is a merge section which matches the
1438 is_merge_section(bool is_string, uint64_t entsize) const
1440 return (this->shndx_ == (is_string
1441 ? MERGE_STRING_SECTION_CODE
1442 : MERGE_DATA_SECTION_CODE)
1443 && this->u1_.entsize == entsize);
1446 // Set the output section.
1448 set_output_section(Output_section* os)
1450 gold_assert(!this->is_input_section());
1451 this->u2_.posd->set_output_section(os);
1454 // Set the address and file offset. This is called during
1455 // Layout::finalize. SECOFF is the file offset of the enclosing
1458 set_address(uint64_t addr, off_t off, off_t secoff);
1460 // Add an input section, for SHF_MERGE sections.
1462 add_input_section(Relobj* object, unsigned int shndx)
1464 gold_assert(this->shndx_ == MERGE_DATA_SECTION_CODE
1465 || this->shndx_ == MERGE_STRING_SECTION_CODE);
1466 return this->u2_.posd->add_input_section(object, shndx);
1469 // Given an input OBJECT, an input section index SHNDX within that
1470 // object, and an OFFSET relative to the start of that input
1471 // section, return whether or not the output address is known.
1472 // OUTPUT_SECTION_ADDRESS is the address of the output section
1473 // which this is a part of. If this function returns true, it
1474 // sets *POUTPUT to the output address.
1476 output_address(const Relobj* object, unsigned int shndx, off_t offset,
1477 uint64_t output_section_address, uint64_t *poutput) const;
1479 // Write out the data. This does nothing for an input section.
1481 write(Output_file*);
1484 // Code values which appear in shndx_. If the value is not one of
1485 // these codes, it is the input section index in the object file.
1488 // An Output_section_data.
1489 OUTPUT_SECTION_CODE = -1U,
1490 // An Output_section_data for an SHF_MERGE section with
1491 // SHF_STRINGS not set.
1492 MERGE_DATA_SECTION_CODE = -2U,
1493 // An Output_section_data for an SHF_MERGE section with
1495 MERGE_STRING_SECTION_CODE = -3U
1498 // Whether this is an input section.
1500 is_input_section() const
1502 return (this->shndx_ != OUTPUT_SECTION_CODE
1503 && this->shndx_ != MERGE_DATA_SECTION_CODE
1504 && this->shndx_ != MERGE_STRING_SECTION_CODE);
1507 // For an ordinary input section, this is the section index in the
1508 // input file. For an Output_section_data, this is
1509 // OUTPUT_SECTION_CODE or MERGE_DATA_SECTION_CODE or
1510 // MERGE_STRING_SECTION_CODE.
1511 unsigned int shndx_;
1512 // The required alignment, stored as a power of 2.
1513 unsigned int p2align_;
1516 // For an ordinary input section, the section size.
1518 // For OUTPUT_SECTION_CODE, this is not used. For
1519 // MERGE_DATA_SECTION_CODE or MERGE_STRING_SECTION_CODE, the
1525 // For an ordinary input section, the object which holds the
1528 // For OUTPUT_SECTION_CODE or MERGE_DATA_SECTION_CODE or
1529 // MERGE_STRING_SECTION_CODE, the data.
1530 Output_section_data* posd;
1534 typedef std::vector<Input_section> Input_section_list;
1536 // Fill data. This is used to fill in data between input sections.
1537 // When we have to keep track of the input sections, we can use an
1538 // Output_data_const, but we don't want to have to keep track of
1539 // input sections just to implement fills. For a fill we record the
1540 // offset, and the actual data to be written out.
1544 Fill(off_t section_offset, off_t length)
1545 : section_offset_(section_offset), length_(length)
1548 // Return section offset.
1550 section_offset() const
1551 { return this->section_offset_; }
1553 // Return fill length.
1556 { return this->length_; }
1559 // The offset within the output section.
1560 off_t section_offset_;
1561 // The length of the space to fill.
1565 typedef std::vector<Fill> Fill_list;
1567 // Add a new output section by Input_section.
1569 add_output_section_data(Input_section*);
1571 // Add an SHF_MERGE input section. Returns true if the section was
1574 add_merge_input_section(Relobj* object, unsigned int shndx, uint64_t flags,
1575 uint64_t entsize, uint64_t addralign);
1577 // Add an output SHF_MERGE section POSD to this output section.
1578 // IS_STRING indicates whether it is a SHF_STRINGS section, and
1579 // ENTSIZE is the entity size. This returns the entry added to
1582 add_output_merge_section(Output_section_data* posd, bool is_string,
1585 // Most of these fields are only valid after layout.
1587 // The name of the section. This will point into a Stringpool.
1589 // The section address is in the parent class.
1590 // The section alignment.
1591 uint64_t addralign_;
1592 // The section entry size.
1594 // The file offset is in the parent class.
1595 // Set the section link field to the index of this section.
1596 const Output_data* link_section_;
1597 // If link_section_ is NULL, this is the link field.
1599 // Set the section info field to the index of this section.
1600 const Output_data* info_section_;
1601 // If info_section_ is NULL, this is the section info field.
1603 // The section type.
1604 elfcpp::Elf_Word type_;
1605 // The section flags.
1606 elfcpp::Elf_Xword flags_;
1607 // The section index.
1608 unsigned int out_shndx_;
1609 // If there is a STT_SECTION for this output section in the normal
1610 // symbol table, this is the symbol index. This starts out as zero.
1611 // It is initialized in Layout::finalize() to be the index, or -1U
1612 // if there isn't one.
1613 unsigned int symtab_index_;
1614 // If there is a STT_SECTION for this output section in the dynamic
1615 // symbol table, this is the symbol index. This starts out as zero.
1616 // It is initialized in Layout::finalize() to be the index, or -1U
1617 // if there isn't one.
1618 unsigned int dynsym_index_;
1619 // The input sections. This will be empty in cases where we don't
1620 // need to keep track of them.
1621 Input_section_list input_sections_;
1622 // The offset of the first entry in input_sections_.
1623 off_t first_input_offset_;
1624 // The fill data. This is separate from input_sections_ because we
1625 // often will need fill sections without needing to keep track of
1628 // Whether this output section needs a STT_SECTION symbol in the
1629 // normal symbol table. This will be true if there is a relocation
1631 bool needs_symtab_index_ : 1;
1632 // Whether this output section needs a STT_SECTION symbol in the
1633 // dynamic symbol table. This will be true if there is a dynamic
1634 // relocation which needs it.
1635 bool needs_dynsym_index_ : 1;
1636 // Whether the link field of this output section should point to the
1637 // normal symbol table.
1638 bool should_link_to_symtab_ : 1;
1639 // Whether the link field of this output section should point to the
1640 // dynamic symbol table.
1641 bool should_link_to_dynsym_ : 1;
1644 // An output segment. PT_LOAD segments are built from collections of
1645 // output sections. Other segments typically point within PT_LOAD
1646 // segments, and are built directly as needed.
1648 class Output_segment
1651 // Create an output segment, specifying the type and flags.
1652 Output_segment(elfcpp::Elf_Word, elfcpp::Elf_Word);
1654 // Return the virtual address.
1657 { return this->vaddr_; }
1659 // Return the physical address.
1662 { return this->paddr_; }
1664 // Return the segment type.
1667 { return this->type_; }
1669 // Return the segment flags.
1672 { return this->flags_; }
1674 // Return the memory size.
1677 { return this->memsz_; }
1679 // Return the file size.
1682 { return this->filesz_; }
1684 // Return the maximum alignment of the Output_data.
1688 // Add an Output_section to this segment.
1690 add_output_section(Output_section* os, elfcpp::Elf_Word seg_flags)
1691 { this->add_output_section(os, seg_flags, false); }
1693 // Add an Output_section to the start of this segment.
1695 add_initial_output_section(Output_section* os, elfcpp::Elf_Word seg_flags)
1696 { this->add_output_section(os, seg_flags, true); }
1698 // Add an Output_data (which is not an Output_section) to the start
1701 add_initial_output_data(Output_data*);
1703 // Set the address of the segment to ADDR and the offset to *POFF
1704 // (aligned if necessary), and set the addresses and offsets of all
1705 // contained output sections accordingly. Set the section indexes
1706 // of all contained output sections starting with *PSHNDX. Return
1707 // the address of the immediately following segment. Update *POFF
1708 // and *PSHNDX. This should only be called for a PT_LOAD segment.
1710 set_section_addresses(uint64_t addr, off_t* poff, unsigned int* pshndx);
1712 // Set the minimum alignment of this segment. This may be adjusted
1713 // upward based on the section alignments.
1715 set_minimum_addralign(uint64_t align)
1717 gold_assert(!this->is_align_known_);
1718 this->align_ = align;
1721 // Set the offset of this segment based on the section. This should
1722 // only be called for a non-PT_LOAD segment.
1726 // Return the number of output sections.
1728 output_section_count() const;
1730 // Write the segment header into *OPHDR.
1731 template<int size, bool big_endian>
1733 write_header(elfcpp::Phdr_write<size, big_endian>*);
1735 // Write the section headers of associated sections into V.
1736 template<int size, bool big_endian>
1738 write_section_headers(const Layout*, const Stringpool*, unsigned char* v,
1739 unsigned int* pshndx ACCEPT_SIZE_ENDIAN) const;
1742 Output_segment(const Output_segment&);
1743 Output_segment& operator=(const Output_segment&);
1745 typedef std::list<Output_data*> Output_data_list;
1747 // Add an Output_section to this segment, specifying front or back.
1749 add_output_section(Output_section*, elfcpp::Elf_Word seg_flags,
1752 // Find the maximum alignment in an Output_data_list.
1754 maximum_alignment(const Output_data_list*);
1756 // Set the section addresses in an Output_data_list.
1758 set_section_list_addresses(Output_data_list*, uint64_t addr, off_t* poff,
1759 unsigned int* pshndx);
1761 // Return the number of Output_sections in an Output_data_list.
1763 output_section_count_list(const Output_data_list*) const;
1765 // Write the section headers in the list into V.
1766 template<int size, bool big_endian>
1768 write_section_headers_list(const Layout*, const Stringpool*,
1769 const Output_data_list*, unsigned char* v,
1770 unsigned int* pshdx ACCEPT_SIZE_ENDIAN) const;
1772 // The list of output data with contents attached to this segment.
1773 Output_data_list output_data_;
1774 // The list of output data without contents attached to this segment.
1775 Output_data_list output_bss_;
1776 // The segment virtual address.
1778 // The segment physical address.
1780 // The size of the segment in memory.
1782 // The segment alignment. The is_align_known_ field indicates
1783 // whether this has been finalized. It can be set to a minimum
1784 // value before it is finalized.
1786 // The offset of the segment data within the file.
1788 // The size of the segment data in the file.
1790 // The segment type;
1791 elfcpp::Elf_Word type_;
1792 // The segment flags.
1793 elfcpp::Elf_Word flags_;
1794 // Whether we have finalized align_.
1795 bool is_align_known_;
1798 // This class represents the output file.
1803 Output_file(const General_options& options, Target*);
1805 // Get a pointer to the target.
1808 { return this->target_; }
1810 // Open the output file. FILE_SIZE is the final size of the file.
1812 open(off_t file_size);
1814 // Close the output file and make sure there are no error.
1818 // We currently always use mmap which makes the view handling quite
1819 // simple. In the future we may support other approaches.
1821 // Write data to the output file.
1823 write(off_t offset, const void* data, off_t len)
1824 { memcpy(this->base_ + offset, data, len); }
1826 // Get a buffer to use to write to the file, given the offset into
1827 // the file and the size.
1829 get_output_view(off_t start, off_t size)
1831 gold_assert(start >= 0 && size >= 0 && start + size <= this->file_size_);
1832 return this->base_ + start;
1835 // VIEW must have been returned by get_output_view. Write the
1836 // buffer to the file, passing in the offset and the size.
1838 write_output_view(off_t, off_t, unsigned char*)
1843 const General_options& options_;
1852 // Base of file mapped into memory.
1853 unsigned char* base_;
1856 } // End namespace gold.
1858 #endif // !defined(GOLD_OUTPUT_H)