1 // output.h -- manage the output file for gold -*- C++ -*-
3 // Copyright 2006, 2007 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.
31 #include "reloc-types.h"
36 class General_options
;
42 template<int size
, bool big_endian
>
44 template<int size
, bool big_endian
>
47 // An abtract class for data which has to go into the output file.
52 explicit Output_data()
53 : address_(0), data_size_(0), offset_(-1),
54 is_address_valid_(false), is_data_size_valid_(false),
55 is_offset_valid_(false),
56 dynamic_reloc_count_(0)
62 // Return the address. For allocated sections, this is only valid
63 // after Layout::finalize is finished.
67 gold_assert(this->is_address_valid_
);
68 return this->address_
;
71 // Return the size of the data. For allocated sections, this must
72 // be valid after Layout::finalize calls set_address, but need not
73 // be valid before then.
77 gold_assert(this->is_data_size_valid_
);
78 return this->data_size_
;
81 // Return the file offset. This is only valid after
82 // Layout::finalize is finished. For some non-allocated sections,
83 // it may not be valid until near the end of the link.
87 gold_assert(this->is_offset_valid_
);
91 // Return the required alignment.
94 { return this->do_addralign(); }
96 // Return whether this is an Output_section.
99 { return this->do_is_section(); }
101 // Return whether this is an Output_section of the specified type.
103 is_section_type(elfcpp::Elf_Word stt
) const
104 { return this->do_is_section_type(stt
); }
106 // Return whether this is an Output_section with the specified flag
109 is_section_flag_set(elfcpp::Elf_Xword shf
) const
110 { return this->do_is_section_flag_set(shf
); }
112 // Return the output section index, if there is an output section.
115 { return this->do_out_shndx(); }
117 // Set the output section index, if this is an output section.
119 set_out_shndx(unsigned int shndx
)
120 { this->do_set_out_shndx(shndx
); }
122 // Set the address and file offset of this data, and finalize the
123 // size of the data. This is called during Layout::finalize for
124 // allocated sections.
126 set_address_and_file_offset(uint64_t addr
, off_t off
)
128 this->set_address(addr
);
129 this->set_file_offset(off
);
130 this->finalize_data_size();
135 set_address(uint64_t addr
)
137 gold_assert(!this->is_address_valid_
);
138 this->address_
= addr
;
139 this->is_address_valid_
= true;
142 // Set the file offset.
144 set_file_offset(off_t off
)
146 gold_assert(!this->is_offset_valid_
);
148 this->is_offset_valid_
= true;
151 // Finalize the data size.
155 if (!this->is_data_size_valid_
)
157 // Tell the child class to set the data size.
158 this->set_final_data_size();
159 gold_assert(this->is_data_size_valid_
);
163 // Set the TLS offset. Called only for SHT_TLS sections.
165 set_tls_offset(uint64_t tls_base
)
166 { this->do_set_tls_offset(tls_base
); }
168 // Return the TLS offset, relative to the base of the TLS segment.
169 // Valid only for SHT_TLS sections.
172 { return this->do_tls_offset(); }
174 // Write the data to the output file. This is called after
175 // Layout::finalize is complete.
177 write(Output_file
* file
)
178 { this->do_write(file
); }
180 // This is called by Layout::finalize to note that the sizes of
181 // allocated sections must now be fixed.
184 { Output_data::allocated_sizes_are_fixed
= true; }
186 // Used to check that layout has been done.
189 { return Output_data::allocated_sizes_are_fixed
; }
191 // Count the number of dynamic relocations applied to this section.
194 { ++this->dynamic_reloc_count_
; }
196 // Return the number of dynamic relocations applied to this section.
198 dynamic_reloc_count() const
199 { return this->dynamic_reloc_count_
; }
201 // Whether the address is valid.
203 is_address_valid() const
204 { return this->is_address_valid_
; }
206 // Whether the file offset is valid.
208 is_offset_valid() const
209 { return this->is_offset_valid_
; }
211 // Whether the data size is valid.
213 is_data_size_valid() const
214 { return this->is_data_size_valid_
; }
217 // Functions that child classes may or in some cases must implement.
219 // Write the data to the output file.
221 do_write(Output_file
*) = 0;
223 // Return the required alignment.
225 do_addralign() const = 0;
227 // Return whether this is an Output_section.
229 do_is_section() const
232 // Return whether this is an Output_section of the specified type.
233 // This only needs to be implement by Output_section.
235 do_is_section_type(elfcpp::Elf_Word
) const
238 // Return whether this is an Output_section with the specific flag
239 // set. This only needs to be implemented by Output_section.
241 do_is_section_flag_set(elfcpp::Elf_Xword
) const
244 // Return the output section index, if there is an output section.
247 { gold_unreachable(); }
249 // Set the output section index, if this is an output section.
251 do_set_out_shndx(unsigned int)
252 { gold_unreachable(); }
254 // This is a hook for derived classes to set the data size. This is
255 // called by finalize_data_size, normally called during
256 // Layout::finalize, when the section address is set.
258 set_final_data_size()
259 { gold_unreachable(); }
261 // Set the TLS offset. Called only for SHT_TLS sections.
263 do_set_tls_offset(uint64_t)
264 { gold_unreachable(); }
266 // Return the TLS offset, relative to the base of the TLS segment.
267 // Valid only for SHT_TLS sections.
269 do_tls_offset() const
270 { gold_unreachable(); }
272 // Functions that child classes may call.
274 // Set the size of the data.
276 set_data_size(off_t data_size
)
278 gold_assert(!this->is_data_size_valid_
);
279 this->data_size_
= data_size
;
280 this->is_data_size_valid_
= true;
283 // Get the current data size--this is for the convenience of
284 // sections which build up their size over time.
286 current_data_size_for_child() const
287 { return this->data_size_
; }
289 // Set the current data size--this is for the convenience of
290 // sections which build up their size over time.
292 set_current_data_size_for_child(off_t data_size
)
294 gold_assert(!this->is_data_size_valid_
);
295 this->data_size_
= data_size
;
298 // Return default alignment for the target size.
302 // Return default alignment for a specified size--32 or 64.
304 default_alignment_for_size(int size
);
307 Output_data(const Output_data
&);
308 Output_data
& operator=(const Output_data
&);
310 // This is used for verification, to make sure that we don't try to
311 // change any sizes of allocated sections after we set the section
313 static bool allocated_sizes_are_fixed
;
315 // Memory address in output file.
317 // Size of data in output file.
319 // File offset of contents in output file.
321 // Whether address_ is valid.
322 bool is_address_valid_
;
323 // Whether data_size_ is valid.
324 bool is_data_size_valid_
;
325 // Whether offset_ is valid.
326 bool is_offset_valid_
;
327 // Count of dynamic relocations applied to this section.
328 unsigned int dynamic_reloc_count_
;
331 // Output the section headers.
333 class Output_section_headers
: public Output_data
336 Output_section_headers(const Layout
*,
337 const Layout::Segment_list
*,
338 const Layout::Section_list
*,
342 // Write the data to the file.
344 do_write(Output_file
*);
346 // Return the required alignment.
349 { return Output_data::default_alignment(); }
352 // Write the data to the file with the right size and endianness.
353 template<int size
, bool big_endian
>
355 do_sized_write(Output_file
*);
357 const Layout
* layout_
;
358 const Layout::Segment_list
* segment_list_
;
359 const Layout::Section_list
* unattached_section_list_
;
360 const Stringpool
* secnamepool_
;
363 // Output the segment headers.
365 class Output_segment_headers
: public Output_data
368 Output_segment_headers(const Layout::Segment_list
& segment_list
);
371 // Write the data to the file.
373 do_write(Output_file
*);
375 // Return the required alignment.
378 { return Output_data::default_alignment(); }
381 // Write the data to the file with the right size and endianness.
382 template<int size
, bool big_endian
>
384 do_sized_write(Output_file
*);
386 const Layout::Segment_list
& segment_list_
;
389 // Output the ELF file header.
391 class Output_file_header
: public Output_data
394 Output_file_header(const Target
*,
396 const Output_segment_headers
*,
399 // Add information about the section headers. We lay out the ELF
400 // file header before we create the section headers.
401 void set_section_info(const Output_section_headers
*,
402 const Output_section
* shstrtab
);
405 // Write the data to the file.
407 do_write(Output_file
*);
409 // Return the required alignment.
412 { return Output_data::default_alignment(); }
415 // Write the data to the file with the right size and endianness.
416 template<int size
, bool big_endian
>
418 do_sized_write(Output_file
*);
420 // Return the value to use for the entry address.
422 typename
elfcpp::Elf_types
<size
>::Elf_Addr
425 const Target
* target_
;
426 const Symbol_table
* symtab_
;
427 const Output_segment_headers
* segment_header_
;
428 const Output_section_headers
* section_header_
;
429 const Output_section
* shstrtab_
;
433 // Output sections are mainly comprised of input sections. However,
434 // there are cases where we have data to write out which is not in an
435 // input section. Output_section_data is used in such cases. This is
436 // an abstract base class.
438 class Output_section_data
: public Output_data
441 Output_section_data(off_t data_size
, uint64_t addralign
)
442 : Output_data(), output_section_(NULL
), addralign_(addralign
)
443 { this->set_data_size(data_size
); }
445 Output_section_data(uint64_t addralign
)
446 : Output_data(), output_section_(NULL
), addralign_(addralign
)
449 // Return the output section.
450 const Output_section
*
451 output_section() const
452 { return this->output_section_
; }
454 // Record the output section.
456 set_output_section(Output_section
* os
);
458 // Add an input section, for SHF_MERGE sections. This returns true
459 // if the section was handled.
461 add_input_section(Relobj
* object
, unsigned int shndx
)
462 { return this->do_add_input_section(object
, shndx
); }
464 // Given an input OBJECT, an input section index SHNDX within that
465 // object, and an OFFSET relative to the start of that input
466 // section, return whether or not the corresponding offset within
467 // the output section is known. If this function returns true, it
468 // sets *POUTPUT to the output offset. The value -1 indicates that
469 // this input offset is being discarded.
471 output_offset(const Relobj
* object
, unsigned int shndx
,
472 section_offset_type offset
,
473 section_offset_type
*poutput
) const
474 { return this->do_output_offset(object
, shndx
, offset
, poutput
); }
476 // Return whether this is the merge section for the input section
477 // SHNDX in OBJECT. This should return true when output_offset
478 // would return true for some values of OFFSET.
480 is_merge_section_for(const Relobj
* object
, unsigned int shndx
) const
481 { return this->do_is_merge_section_for(object
, shndx
); }
483 // Write the contents to a buffer. This is used for sections which
484 // require postprocessing, such as compression.
486 write_to_buffer(unsigned char* buffer
)
487 { this->do_write_to_buffer(buffer
); }
489 // Print merge stats to stderr. This should only be called for
490 // SHF_MERGE sections.
492 print_merge_stats(const char* section_name
)
493 { this->do_print_merge_stats(section_name
); }
496 // The child class must implement do_write.
498 // The child class may implement specific adjustments to the output
501 do_adjust_output_section(Output_section
*)
504 // May be implemented by child class. Return true if the section
507 do_add_input_section(Relobj
*, unsigned int)
508 { gold_unreachable(); }
510 // The child class may implement output_offset.
512 do_output_offset(const Relobj
*, unsigned int, section_offset_type
,
513 section_offset_type
*) const
516 // The child class may implement is_merge_section_for.
518 do_is_merge_section_for(const Relobj
*, unsigned int) const
521 // The child class may implement write_to_buffer. Most child
522 // classes can not appear in a compressed section, and they do not
525 do_write_to_buffer(unsigned char*)
526 { gold_unreachable(); }
528 // Print merge statistics.
530 do_print_merge_stats(const char*)
531 { gold_unreachable(); }
533 // Return the required alignment.
536 { return this->addralign_
; }
538 // Return the section index of the output section.
540 do_out_shndx() const;
542 // Set the alignment.
544 set_addralign(uint64_t addralign
)
545 { this->addralign_
= addralign
; }
548 // The output section for this section.
549 const Output_section
* output_section_
;
550 // The required alignment.
554 // Some Output_section_data classes build up their data step by step,
555 // rather than all at once. This class provides an interface for
558 class Output_section_data_build
: public Output_section_data
561 Output_section_data_build(uint64_t addralign
)
562 : Output_section_data(addralign
)
565 // Get the current data size.
567 current_data_size() const
568 { return this->current_data_size_for_child(); }
570 // Set the current data size.
572 set_current_data_size(off_t data_size
)
573 { this->set_current_data_size_for_child(data_size
); }
576 // Set the final data size.
578 set_final_data_size()
579 { this->set_data_size(this->current_data_size_for_child()); }
582 // A simple case of Output_data in which we have constant data to
585 class Output_data_const
: public Output_section_data
588 Output_data_const(const std::string
& data
, uint64_t addralign
)
589 : Output_section_data(data
.size(), addralign
), data_(data
)
592 Output_data_const(const char* p
, off_t len
, uint64_t addralign
)
593 : Output_section_data(len
, addralign
), data_(p
, len
)
596 Output_data_const(const unsigned char* p
, off_t len
, uint64_t addralign
)
597 : Output_section_data(len
, addralign
),
598 data_(reinterpret_cast<const char*>(p
), len
)
602 // Write the data to the output file.
604 do_write(Output_file
*);
606 // Write the data to a buffer.
608 do_write_to_buffer(unsigned char* buffer
)
609 { memcpy(buffer
, this->data_
.data(), this->data_
.size()); }
615 // Another version of Output_data with constant data, in which the
616 // buffer is allocated by the caller.
618 class Output_data_const_buffer
: public Output_section_data
621 Output_data_const_buffer(const unsigned char* p
, off_t len
,
623 : Output_section_data(len
, addralign
), p_(p
)
627 // Write the data the output file.
629 do_write(Output_file
*);
631 // Write the data to a buffer.
633 do_write_to_buffer(unsigned char* buffer
)
634 { memcpy(buffer
, this->p_
, this->data_size()); }
637 const unsigned char* p_
;
640 // A place holder for a fixed amount of data written out via some
643 class Output_data_fixed_space
: public Output_section_data
646 Output_data_fixed_space(off_t data_size
, uint64_t addralign
)
647 : Output_section_data(data_size
, addralign
)
651 // Write out the data--the actual data must be written out
654 do_write(Output_file
*)
658 // A place holder for variable sized data written out via some other
661 class Output_data_space
: public Output_section_data_build
664 explicit Output_data_space(uint64_t addralign
)
665 : Output_section_data_build(addralign
)
668 // Set the alignment.
670 set_space_alignment(uint64_t align
)
671 { this->set_addralign(align
); }
674 // Write out the data--the actual data must be written out
677 do_write(Output_file
*)
681 // A string table which goes into an output section.
683 class Output_data_strtab
: public Output_section_data
686 Output_data_strtab(Stringpool
* strtab
)
687 : Output_section_data(1), strtab_(strtab
)
691 // This is called to set the address and file offset. Here we make
692 // sure that the Stringpool is finalized.
694 set_final_data_size();
696 // Write out the data.
698 do_write(Output_file
*);
700 // Write the data to a buffer.
702 do_write_to_buffer(unsigned char* buffer
)
703 { this->strtab_
->write_to_buffer(buffer
, this->data_size()); }
709 // This POD class is used to represent a single reloc in the output
710 // file. This could be a private class within Output_data_reloc, but
711 // the templatization is complex enough that I broke it out into a
712 // separate class. The class is templatized on either elfcpp::SHT_REL
713 // or elfcpp::SHT_RELA, and also on whether this is a dynamic
714 // relocation or an ordinary relocation.
716 // A relocation can be against a global symbol, a local symbol, an
717 // output section, or the undefined symbol at index 0. We represent
718 // the latter by using a NULL global symbol.
720 template<int sh_type
, bool dynamic
, int size
, bool big_endian
>
723 template<bool dynamic
, int size
, bool big_endian
>
724 class Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>
727 typedef typename
elfcpp::Elf_types
<size
>::Elf_Addr Address
;
729 // An uninitialized entry. We need this because we want to put
730 // instances of this class into an STL container.
732 : local_sym_index_(INVALID_CODE
)
735 // A reloc against a global symbol.
737 Output_reloc(Symbol
* gsym
, unsigned int type
, Output_data
* od
,
738 Address address
, bool is_relative
);
740 Output_reloc(Symbol
* gsym
, unsigned int type
, Relobj
* relobj
,
741 unsigned int shndx
, Address address
, bool is_relative
);
743 // A reloc against a local symbol.
745 Output_reloc(Sized_relobj
<size
, big_endian
>* relobj
,
746 unsigned int local_sym_index
, unsigned int type
,
747 Output_data
* od
, Address address
, bool is_relative
);
749 Output_reloc(Sized_relobj
<size
, big_endian
>* relobj
,
750 unsigned int local_sym_index
, unsigned int type
,
751 unsigned int shndx
, Address address
, bool is_relative
);
753 // A reloc against the STT_SECTION symbol of an output section.
755 Output_reloc(Output_section
* os
, unsigned int type
, Output_data
* od
,
758 Output_reloc(Output_section
* os
, unsigned int type
, Relobj
* relobj
,
759 unsigned int shndx
, Address address
);
761 // Return TRUE if this is a RELATIVE relocation.
764 { return this->is_relative_
; }
766 // Get the value of the symbol referred to by a Rel relocation.
769 symbol_value() const;
771 // Write the reloc entry to an output view.
773 write(unsigned char* pov
) const;
775 // Write the offset and info fields to Write_rel.
776 template<typename Write_rel
>
777 void write_rel(Write_rel
*) const;
780 // Return the symbol index. We can't do a double template
781 // specialization, so we do a secondary template here.
783 get_symbol_index() const;
785 // Codes for local_sym_index_.
792 // Invalid uninitialized entry.
798 // For a local symbol, the object. We will never generate a
799 // relocation against a local symbol in a dynamic object; that
800 // doesn't make sense. And our callers will always be
801 // templatized, so we use Sized_relobj here.
802 Sized_relobj
<size
, big_endian
>* relobj
;
803 // For a global symbol, the symbol. If this is NULL, it indicates
804 // a relocation against the undefined 0 symbol.
806 // For a relocation against an output section, the output section.
811 // If shndx_ is not INVALID CODE, the object which holds the input
812 // section being used to specify the reloc address.
814 // If shndx_ is INVALID_CODE, the output data being used to
815 // specify the reloc address. This may be NULL if the reloc
816 // address is absolute.
819 // The address offset within the input section or the Output_data.
821 // For a local symbol, the local symbol index. This is GSYM_CODE
822 // for a global symbol, or INVALID_CODE for an uninitialized value.
823 unsigned int local_sym_index_
;
824 // The reloc type--a processor specific code.
825 unsigned int type_
: 31;
826 // True if the relocation is a RELATIVE relocation.
827 bool is_relative_
: 1;
828 // If the reloc address is an input section in an object, the
829 // section index. This is INVALID_CODE if the reloc address is
830 // specified in some other way.
834 // The SHT_RELA version of Output_reloc<>. This is just derived from
835 // the SHT_REL version of Output_reloc, but it adds an addend.
837 template<bool dynamic
, int size
, bool big_endian
>
838 class Output_reloc
<elfcpp::SHT_RELA
, dynamic
, size
, big_endian
>
841 typedef typename
elfcpp::Elf_types
<size
>::Elf_Addr Address
;
842 typedef typename
elfcpp::Elf_types
<size
>::Elf_Addr Addend
;
844 // An uninitialized entry.
849 // A reloc against a global symbol.
851 Output_reloc(Symbol
* gsym
, unsigned int type
, Output_data
* od
,
852 Address address
, Addend addend
, bool is_relative
)
853 : rel_(gsym
, type
, od
, address
, is_relative
), addend_(addend
)
856 Output_reloc(Symbol
* gsym
, unsigned int type
, Relobj
* relobj
,
857 unsigned int shndx
, Address address
, Addend addend
,
859 : rel_(gsym
, type
, relobj
, shndx
, address
, is_relative
), addend_(addend
)
862 // A reloc against a local symbol.
864 Output_reloc(Sized_relobj
<size
, big_endian
>* relobj
,
865 unsigned int local_sym_index
, unsigned int type
,
866 Output_data
* od
, Address address
,
867 Addend addend
, bool is_relative
)
868 : rel_(relobj
, local_sym_index
, type
, od
, address
, is_relative
),
872 Output_reloc(Sized_relobj
<size
, big_endian
>* relobj
,
873 unsigned int local_sym_index
, unsigned int type
,
874 unsigned int shndx
, Address address
,
875 Addend addend
, bool is_relative
)
876 : rel_(relobj
, local_sym_index
, type
, shndx
, address
, is_relative
),
880 // A reloc against the STT_SECTION symbol of an output section.
882 Output_reloc(Output_section
* os
, unsigned int type
, Output_data
* od
,
883 Address address
, Addend addend
)
884 : rel_(os
, type
, od
, address
), addend_(addend
)
887 Output_reloc(Output_section
* os
, unsigned int type
, Relobj
* relobj
,
888 unsigned int shndx
, Address address
, Addend addend
)
889 : rel_(os
, type
, relobj
, shndx
, address
), addend_(addend
)
892 // Write the reloc entry to an output view.
894 write(unsigned char* pov
) const;
898 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
> rel_
;
903 // Output_data_reloc is used to manage a section containing relocs.
904 // SH_TYPE is either elfcpp::SHT_REL or elfcpp::SHT_RELA. DYNAMIC
905 // indicates whether this is a dynamic relocation or a normal
906 // relocation. Output_data_reloc_base is a base class.
907 // Output_data_reloc is the real class, which we specialize based on
910 template<int sh_type
, bool dynamic
, int size
, bool big_endian
>
911 class Output_data_reloc_base
: public Output_section_data_build
914 typedef Output_reloc
<sh_type
, dynamic
, size
, big_endian
> Output_reloc_type
;
915 typedef typename
Output_reloc_type::Address Address
;
916 static const int reloc_size
=
917 Reloc_types
<sh_type
, size
, big_endian
>::reloc_size
;
919 // Construct the section.
920 Output_data_reloc_base()
921 : Output_section_data_build(Output_data::default_alignment_for_size(size
))
925 // Write out the data.
927 do_write(Output_file
*);
929 // Set the entry size and the link.
931 do_adjust_output_section(Output_section
*os
);
933 // Add a relocation entry.
935 add(Output_data
*od
, const Output_reloc_type
& reloc
)
937 this->relocs_
.push_back(reloc
);
938 this->set_current_data_size(this->relocs_
.size() * reloc_size
);
939 od
->add_dynamic_reloc();
943 typedef std::vector
<Output_reloc_type
> Relocs
;
948 // The class which callers actually create.
950 template<int sh_type
, bool dynamic
, int size
, bool big_endian
>
951 class Output_data_reloc
;
953 // The SHT_REL version of Output_data_reloc.
955 template<bool dynamic
, int size
, bool big_endian
>
956 class Output_data_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>
957 : public Output_data_reloc_base
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>
960 typedef Output_data_reloc_base
<elfcpp::SHT_REL
, dynamic
, size
,
964 typedef typename
Base::Output_reloc_type Output_reloc_type
;
965 typedef typename
Output_reloc_type::Address Address
;
968 : Output_data_reloc_base
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>()
971 // Add a reloc against a global symbol.
974 add_global(Symbol
* gsym
, unsigned int type
, Output_data
* od
, Address address
)
975 { this->add(od
, Output_reloc_type(gsym
, type
, od
, address
, false)); }
978 add_global(Symbol
* gsym
, unsigned int type
, Output_data
* od
, Relobj
* relobj
,
979 unsigned int shndx
, Address address
)
980 { this->add(od
, Output_reloc_type(gsym
, type
, relobj
, shndx
, address
,
983 // Add a RELATIVE reloc against a global symbol. The final relocation
984 // will not reference the symbol.
987 add_global_relative(Symbol
* gsym
, unsigned int type
, Output_data
* od
,
989 { this->add(od
, Output_reloc_type(gsym
, type
, od
, address
, true)); }
992 add_global_relative(Symbol
* gsym
, unsigned int type
, Output_data
* od
,
993 Relobj
* relobj
, unsigned int shndx
, Address address
)
994 { this->add(od
, Output_reloc_type(gsym
, type
, relobj
, shndx
, address
,
997 // Add a reloc against a local symbol.
1000 add_local(Sized_relobj
<size
, big_endian
>* relobj
,
1001 unsigned int local_sym_index
, unsigned int type
,
1002 Output_data
* od
, Address address
)
1003 { this->add(od
, Output_reloc_type(relobj
, local_sym_index
, type
, od
,
1007 add_local(Sized_relobj
<size
, big_endian
>* relobj
,
1008 unsigned int local_sym_index
, unsigned int type
,
1009 Output_data
* od
, unsigned int shndx
, Address address
)
1010 { this->add(od
, Output_reloc_type(relobj
, local_sym_index
, type
, shndx
,
1013 // Add a RELATIVE reloc against a local symbol.
1016 add_local_relative(Sized_relobj
<size
, big_endian
>* relobj
,
1017 unsigned int local_sym_index
, unsigned int type
,
1018 Output_data
* od
, Address address
)
1019 { this->add(od
, Output_reloc_type(relobj
, local_sym_index
, type
, od
,
1023 add_local_relative(Sized_relobj
<size
, big_endian
>* relobj
,
1024 unsigned int local_sym_index
, unsigned int type
,
1025 Output_data
* od
, unsigned int shndx
, Address address
)
1026 { this->add(od
, Output_reloc_type(relobj
, local_sym_index
, type
, shndx
,
1029 // A reloc against the STT_SECTION symbol of an output section.
1030 // OS is the Output_section that the relocation refers to; OD is
1031 // the Output_data object being relocated.
1034 add_output_section(Output_section
* os
, unsigned int type
,
1035 Output_data
* od
, Address address
)
1036 { this->add(od
, Output_reloc_type(os
, type
, od
, address
)); }
1039 add_output_section(Output_section
* os
, unsigned int type
, Output_data
* od
,
1040 Relobj
* relobj
, unsigned int shndx
, Address address
)
1041 { this->add(od
, Output_reloc_type(os
, type
, relobj
, shndx
, address
)); }
1044 // The SHT_RELA version of Output_data_reloc.
1046 template<bool dynamic
, int size
, bool big_endian
>
1047 class Output_data_reloc
<elfcpp::SHT_RELA
, dynamic
, size
, big_endian
>
1048 : public Output_data_reloc_base
<elfcpp::SHT_RELA
, dynamic
, size
, big_endian
>
1051 typedef Output_data_reloc_base
<elfcpp::SHT_RELA
, dynamic
, size
,
1055 typedef typename
Base::Output_reloc_type Output_reloc_type
;
1056 typedef typename
Output_reloc_type::Address Address
;
1057 typedef typename
Output_reloc_type::Addend Addend
;
1060 : Output_data_reloc_base
<elfcpp::SHT_RELA
, dynamic
, size
, big_endian
>()
1063 // Add a reloc against a global symbol.
1066 add_global(Symbol
* gsym
, unsigned int type
, Output_data
* od
,
1067 Address address
, Addend addend
)
1068 { this->add(od
, Output_reloc_type(gsym
, type
, od
, address
, addend
,
1072 add_global(Symbol
* gsym
, unsigned int type
, Output_data
* od
, Relobj
* relobj
,
1073 unsigned int shndx
, Address address
,
1075 { this->add(od
, Output_reloc_type(gsym
, type
, relobj
, shndx
, address
,
1078 // Add a RELATIVE reloc against a global symbol. The final output
1079 // relocation will not reference the symbol, but we must keep the symbol
1080 // information long enough to set the addend of the relocation correctly
1081 // when it is written.
1084 add_global_relative(Symbol
* gsym
, unsigned int type
, Output_data
* od
,
1085 Address address
, Addend addend
)
1086 { this->add(od
, Output_reloc_type(gsym
, type
, od
, address
, addend
, true)); }
1089 add_global_relative(Symbol
* gsym
, unsigned int type
, Output_data
* od
,
1090 Relobj
* relobj
, unsigned int shndx
, Address address
,
1092 { this->add(od
, Output_reloc_type(gsym
, type
, relobj
, shndx
, address
,
1095 // Add a reloc against a local symbol.
1098 add_local(Sized_relobj
<size
, big_endian
>* relobj
,
1099 unsigned int local_sym_index
, unsigned int type
,
1100 Output_data
* od
, Address address
, Addend addend
)
1102 this->add(od
, Output_reloc_type(relobj
, local_sym_index
, type
, od
, address
,
1107 add_local(Sized_relobj
<size
, big_endian
>* relobj
,
1108 unsigned int local_sym_index
, unsigned int type
,
1109 Output_data
* od
, unsigned int shndx
, Address address
,
1112 this->add(od
, Output_reloc_type(relobj
, local_sym_index
, type
, shndx
,
1113 address
, addend
, false));
1116 // Add a RELATIVE reloc against a local symbol.
1119 add_local_relative(Sized_relobj
<size
, big_endian
>* relobj
,
1120 unsigned int local_sym_index
, unsigned int type
,
1121 Output_data
* od
, Address address
, Addend addend
)
1123 this->add(od
, Output_reloc_type(relobj
, local_sym_index
, type
, od
, address
,
1128 add_local_relative(Sized_relobj
<size
, big_endian
>* relobj
,
1129 unsigned int local_sym_index
, unsigned int type
,
1130 Output_data
* od
, unsigned int shndx
, Address address
,
1133 this->add(od
, Output_reloc_type(relobj
, local_sym_index
, type
, shndx
,
1134 address
, addend
, true));
1137 // A reloc against the STT_SECTION symbol of an output section.
1140 add_output_section(Output_section
* os
, unsigned int type
, Output_data
* od
,
1141 Address address
, Addend addend
)
1142 { this->add(os
, Output_reloc_type(os
, type
, od
, address
, addend
)); }
1145 add_output_section(Output_section
* os
, unsigned int type
, Relobj
* relobj
,
1146 unsigned int shndx
, Address address
, Addend addend
)
1147 { this->add(os
, Output_reloc_type(os
, type
, relobj
, shndx
, address
,
1151 // Output_data_got is used to manage a GOT. Each entry in the GOT is
1152 // for one symbol--either a global symbol or a local symbol in an
1153 // object. The target specific code adds entries to the GOT as
1156 template<int size
, bool big_endian
>
1157 class Output_data_got
: public Output_section_data_build
1160 typedef typename
elfcpp::Elf_types
<size
>::Elf_Addr Valtype
;
1161 typedef Output_data_reloc
<elfcpp::SHT_REL
, true, size
, big_endian
> Rel_dyn
;
1162 typedef Output_data_reloc
<elfcpp::SHT_RELA
, true, size
, big_endian
> Rela_dyn
;
1165 : Output_section_data_build(Output_data::default_alignment_for_size(size
)),
1169 // Add an entry for a global symbol to the GOT. Return true if this
1170 // is a new GOT entry, false if the symbol was already in the GOT.
1172 add_global(Symbol
* gsym
);
1174 // Add an entry for a global symbol to the GOT, and add a dynamic
1175 // relocation of type R_TYPE for the GOT entry.
1177 add_global_with_rel(Symbol
* gsym
, Rel_dyn
* rel_dyn
, unsigned int r_type
);
1180 add_global_with_rela(Symbol
* gsym
, Rela_dyn
* rela_dyn
, unsigned int r_type
);
1182 // Add an entry for a local symbol to the GOT. This returns true if
1183 // this is a new GOT entry, false if the symbol already has a GOT
1186 add_local(Sized_relobj
<size
, big_endian
>* object
, unsigned int sym_index
);
1188 // Add an entry for a global symbol to the GOT, and add a dynamic
1189 // relocation of type R_TYPE for the GOT entry.
1191 add_local_with_rel(Sized_relobj
<size
, big_endian
>* object
,
1192 unsigned int sym_index
, Rel_dyn
* rel_dyn
,
1193 unsigned int r_type
);
1196 add_local_with_rela(Sized_relobj
<size
, big_endian
>* object
,
1197 unsigned int sym_index
, Rela_dyn
* rela_dyn
,
1198 unsigned int r_type
);
1200 // Add an entry (or pair of entries) for a global TLS symbol to the GOT.
1201 // Return true if this is a new GOT entry, false if the symbol was
1202 // already in the GOT.
1204 add_global_tls(Symbol
* gsym
, bool need_pair
);
1206 // Add an entry for a global TLS symbol to the GOT, and add a dynamic
1207 // relocation of type R_TYPE.
1209 add_global_tls_with_rel(Symbol
* gsym
, Rel_dyn
* rel_dyn
,
1210 unsigned int r_type
);
1213 add_global_tls_with_rela(Symbol
* gsym
, Rela_dyn
* rela_dyn
,
1214 unsigned int r_type
);
1216 // Add a pair of entries for a global TLS symbol to the GOT, and add
1217 // dynamic relocations of type MOD_R_TYPE and DTV_R_TYPE, respectively.
1219 add_global_tls_with_rel(Symbol
* gsym
, Rel_dyn
* rel_dyn
,
1220 unsigned int mod_r_type
,
1221 unsigned int dtv_r_type
);
1224 add_global_tls_with_rela(Symbol
* gsym
, Rela_dyn
* rela_dyn
,
1225 unsigned int mod_r_type
,
1226 unsigned int dtv_r_type
);
1228 // Add an entry (or pair of entries) for a local TLS symbol to the GOT.
1229 // This returns true if this is a new GOT entry, false if the symbol
1230 // already has a GOT entry.
1232 add_local_tls(Sized_relobj
<size
, big_endian
>* object
,
1233 unsigned int sym_index
, bool need_pair
);
1235 // Add an entry (or pair of entries) for a local TLS symbol to the GOT,
1236 // and add a dynamic relocation of type R_TYPE for the first GOT entry.
1237 // Because this is a local symbol, the first GOT entry can be relocated
1238 // relative to a section symbol, and the second GOT entry will have an
1239 // dtv-relative value that can be computed at link time.
1241 add_local_tls_with_rel(Sized_relobj
<size
, big_endian
>* object
,
1242 unsigned int sym_index
, unsigned int shndx
,
1243 bool need_pair
, Rel_dyn
* rel_dyn
,
1244 unsigned int r_type
);
1247 add_local_tls_with_rela(Sized_relobj
<size
, big_endian
>* object
,
1248 unsigned int sym_index
, unsigned int shndx
,
1249 bool need_pair
, Rela_dyn
* rela_dyn
,
1250 unsigned int r_type
);
1252 // Add a constant to the GOT. This returns the offset of the new
1253 // entry from the start of the GOT.
1255 add_constant(Valtype constant
)
1257 this->entries_
.push_back(Got_entry(constant
));
1258 this->set_got_size();
1259 return this->last_got_offset();
1263 // Write out the GOT table.
1265 do_write(Output_file
*);
1268 // This POD class holds a single GOT entry.
1272 // Create a zero entry.
1274 : local_sym_index_(CONSTANT_CODE
)
1275 { this->u_
.constant
= 0; }
1277 // Create a global symbol entry.
1278 explicit Got_entry(Symbol
* gsym
)
1279 : local_sym_index_(GSYM_CODE
)
1280 { this->u_
.gsym
= gsym
; }
1282 // Create a local symbol entry.
1283 Got_entry(Sized_relobj
<size
, big_endian
>* object
,
1284 unsigned int local_sym_index
)
1285 : local_sym_index_(local_sym_index
)
1287 gold_assert(local_sym_index
!= GSYM_CODE
1288 && local_sym_index
!= CONSTANT_CODE
);
1289 this->u_
.object
= object
;
1292 // Create a constant entry. The constant is a host value--it will
1293 // be swapped, if necessary, when it is written out.
1294 explicit Got_entry(Valtype constant
)
1295 : local_sym_index_(CONSTANT_CODE
)
1296 { this->u_
.constant
= constant
; }
1298 // Write the GOT entry to an output view.
1300 write(unsigned char* pov
) const;
1311 // For a local symbol, the object.
1312 Sized_relobj
<size
, big_endian
>* object
;
1313 // For a global symbol, the symbol.
1315 // For a constant, the constant.
1318 // For a local symbol, the local symbol index. This is GSYM_CODE
1319 // for a global symbol, or CONSTANT_CODE for a constant.
1320 unsigned int local_sym_index_
;
1323 typedef std::vector
<Got_entry
> Got_entries
;
1325 // Return the offset into the GOT of GOT entry I.
1327 got_offset(unsigned int i
) const
1328 { return i
* (size
/ 8); }
1330 // Return the offset into the GOT of the last entry added.
1332 last_got_offset() const
1333 { return this->got_offset(this->entries_
.size() - 1); }
1335 // Set the size of the section.
1338 { this->set_current_data_size(this->got_offset(this->entries_
.size())); }
1340 // The list of GOT entries.
1341 Got_entries entries_
;
1344 // Output_data_dynamic is used to hold the data in SHT_DYNAMIC
1347 class Output_data_dynamic
: public Output_section_data
1350 Output_data_dynamic(Stringpool
* pool
)
1351 : Output_section_data(Output_data::default_alignment()),
1352 entries_(), pool_(pool
)
1355 // Add a new dynamic entry with a fixed numeric value.
1357 add_constant(elfcpp::DT tag
, unsigned int val
)
1358 { this->add_entry(Dynamic_entry(tag
, val
)); }
1360 // Add a new dynamic entry with the address of output data.
1362 add_section_address(elfcpp::DT tag
, const Output_data
* od
)
1363 { this->add_entry(Dynamic_entry(tag
, od
, false)); }
1365 // Add a new dynamic entry with the size of output data.
1367 add_section_size(elfcpp::DT tag
, const Output_data
* od
)
1368 { this->add_entry(Dynamic_entry(tag
, od
, true)); }
1370 // Add a new dynamic entry with the address of a symbol.
1372 add_symbol(elfcpp::DT tag
, const Symbol
* sym
)
1373 { this->add_entry(Dynamic_entry(tag
, sym
)); }
1375 // Add a new dynamic entry with a string.
1377 add_string(elfcpp::DT tag
, const char* str
)
1378 { this->add_entry(Dynamic_entry(tag
, this->pool_
->add(str
, true, NULL
))); }
1381 add_string(elfcpp::DT tag
, const std::string
& str
)
1382 { this->add_string(tag
, str
.c_str()); }
1385 // Adjust the output section to set the entry size.
1387 do_adjust_output_section(Output_section
*);
1389 // Set the final data size.
1391 set_final_data_size();
1393 // Write out the dynamic entries.
1395 do_write(Output_file
*);
1398 // This POD class holds a single dynamic entry.
1402 // Create an entry with a fixed numeric value.
1403 Dynamic_entry(elfcpp::DT tag
, unsigned int val
)
1404 : tag_(tag
), classification_(DYNAMIC_NUMBER
)
1405 { this->u_
.val
= val
; }
1407 // Create an entry with the size or address of a section.
1408 Dynamic_entry(elfcpp::DT tag
, const Output_data
* od
, bool section_size
)
1410 classification_(section_size
1411 ? DYNAMIC_SECTION_SIZE
1412 : DYNAMIC_SECTION_ADDRESS
)
1413 { this->u_
.od
= od
; }
1415 // Create an entry with the address of a symbol.
1416 Dynamic_entry(elfcpp::DT tag
, const Symbol
* sym
)
1417 : tag_(tag
), classification_(DYNAMIC_SYMBOL
)
1418 { this->u_
.sym
= sym
; }
1420 // Create an entry with a string.
1421 Dynamic_entry(elfcpp::DT tag
, const char* str
)
1422 : tag_(tag
), classification_(DYNAMIC_STRING
)
1423 { this->u_
.str
= str
; }
1425 // Write the dynamic entry to an output view.
1426 template<int size
, bool big_endian
>
1428 write(unsigned char* pov
, const Stringpool
* ACCEPT_SIZE_ENDIAN
) const;
1436 DYNAMIC_SECTION_ADDRESS
,
1438 DYNAMIC_SECTION_SIZE
,
1447 // For DYNAMIC_NUMBER.
1449 // For DYNAMIC_SECTION_ADDRESS and DYNAMIC_SECTION_SIZE.
1450 const Output_data
* od
;
1451 // For DYNAMIC_SYMBOL.
1453 // For DYNAMIC_STRING.
1458 // The type of entry.
1459 Classification classification_
;
1462 // Add an entry to the list.
1464 add_entry(const Dynamic_entry
& entry
)
1465 { this->entries_
.push_back(entry
); }
1467 // Sized version of write function.
1468 template<int size
, bool big_endian
>
1470 sized_write(Output_file
* of
);
1472 // The type of the list of entries.
1473 typedef std::vector
<Dynamic_entry
> Dynamic_entries
;
1476 Dynamic_entries entries_
;
1477 // The pool used for strings.
1481 // An output section. We don't expect to have too many output
1482 // sections, so we don't bother to do a template on the size.
1484 class Output_section
: public Output_data
1487 // Create an output section, giving the name, type, and flags.
1488 Output_section(const char* name
, elfcpp::Elf_Word
, elfcpp::Elf_Xword
);
1489 virtual ~Output_section();
1491 // Add a new input section SHNDX, named NAME, with header SHDR, from
1492 // object OBJECT. RELOC_SHNDX is the index of a relocation section
1493 // which applies to this section, or 0 if none, or -1U if more than
1494 // one. Return the offset within the output section.
1495 template<int size
, bool big_endian
>
1497 add_input_section(Sized_relobj
<size
, big_endian
>* object
, unsigned int shndx
,
1499 const elfcpp::Shdr
<size
, big_endian
>& shdr
,
1500 unsigned int reloc_shndx
);
1502 // Add generated data POSD to this output section.
1504 add_output_section_data(Output_section_data
* posd
);
1506 // Return the section name.
1509 { return this->name_
; }
1511 // Return the section type.
1514 { return this->type_
; }
1516 // Return the section flags.
1519 { return this->flags_
; }
1521 // Return the entsize field.
1524 { return this->entsize_
; }
1526 // Set the entsize field.
1528 set_entsize(uint64_t v
);
1530 // Set the link field to the output section index of a section.
1532 set_link_section(const Output_data
* od
)
1534 gold_assert(this->link_
== 0
1535 && !this->should_link_to_symtab_
1536 && !this->should_link_to_dynsym_
);
1537 this->link_section_
= od
;
1540 // Set the link field to a constant.
1542 set_link(unsigned int v
)
1544 gold_assert(this->link_section_
== NULL
1545 && !this->should_link_to_symtab_
1546 && !this->should_link_to_dynsym_
);
1550 // Record that this section should link to the normal symbol table.
1552 set_should_link_to_symtab()
1554 gold_assert(this->link_section_
== NULL
1556 && !this->should_link_to_dynsym_
);
1557 this->should_link_to_symtab_
= true;
1560 // Record that this section should link to the dynamic symbol table.
1562 set_should_link_to_dynsym()
1564 gold_assert(this->link_section_
== NULL
1566 && !this->should_link_to_symtab_
);
1567 this->should_link_to_dynsym_
= true;
1570 // Return the info field.
1574 gold_assert(this->info_section_
== NULL
);
1578 // Set the info field to the output section index of a section.
1580 set_info_section(const Output_data
* od
)
1582 gold_assert(this->info_
== 0);
1583 this->info_section_
= od
;
1586 // Set the info field to a constant.
1588 set_info(unsigned int v
)
1590 gold_assert(this->info_section_
== NULL
);
1594 // Set the addralign field.
1596 set_addralign(uint64_t v
)
1597 { this->addralign_
= v
; }
1599 // Indicate that we need a symtab index.
1601 set_needs_symtab_index()
1602 { this->needs_symtab_index_
= true; }
1604 // Return whether we need a symtab index.
1606 needs_symtab_index() const
1607 { return this->needs_symtab_index_
; }
1609 // Get the symtab index.
1611 symtab_index() const
1613 gold_assert(this->symtab_index_
!= 0);
1614 return this->symtab_index_
;
1617 // Set the symtab index.
1619 set_symtab_index(unsigned int index
)
1621 gold_assert(index
!= 0);
1622 this->symtab_index_
= index
;
1625 // Indicate that we need a dynsym index.
1627 set_needs_dynsym_index()
1628 { this->needs_dynsym_index_
= true; }
1630 // Return whether we need a dynsym index.
1632 needs_dynsym_index() const
1633 { return this->needs_dynsym_index_
; }
1635 // Get the dynsym index.
1637 dynsym_index() const
1639 gold_assert(this->dynsym_index_
!= 0);
1640 return this->dynsym_index_
;
1643 // Set the dynsym index.
1645 set_dynsym_index(unsigned int index
)
1647 gold_assert(index
!= 0);
1648 this->dynsym_index_
= index
;
1651 // Return whether this section should be written after all the input
1652 // sections are complete.
1654 after_input_sections() const
1655 { return this->after_input_sections_
; }
1657 // Record that this section should be written after all the input
1658 // sections are complete.
1660 set_after_input_sections()
1661 { this->after_input_sections_
= true; }
1663 // Return whether this section requires postprocessing after all
1664 // relocations have been applied.
1666 requires_postprocessing() const
1667 { return this->requires_postprocessing_
; }
1669 // If a section requires postprocessing, return the buffer to use.
1671 postprocessing_buffer() const
1673 gold_assert(this->postprocessing_buffer_
!= NULL
);
1674 return this->postprocessing_buffer_
;
1677 // If a section requires postprocessing, create the buffer to use.
1679 create_postprocessing_buffer();
1681 // If a section requires postprocessing, this is the size of the
1682 // buffer to which relocations should be applied.
1684 postprocessing_buffer_size() const
1685 { return this->current_data_size_for_child(); }
1687 // Return whether the offset OFFSET in the input section SHNDX in
1688 // object OBJECT is being included in the link.
1690 is_input_address_mapped(const Relobj
* object
, unsigned int shndx
,
1691 off_t offset
) const;
1693 // Return the offset within the output section of OFFSET relative to
1694 // the start of input section SHNDX in object OBJECT.
1696 output_offset(const Relobj
* object
, unsigned int shndx
,
1697 section_offset_type offset
) const;
1699 // Return the output virtual address of OFFSET relative to the start
1700 // of input section SHNDX in object OBJECT.
1702 output_address(const Relobj
* object
, unsigned int shndx
,
1703 off_t offset
) const;
1705 // Return the output address of the start of the merged section for
1706 // input section SHNDX in object OBJECT. This is not necessarily
1707 // the offset corresponding to input offset 0 in the section, since
1708 // the section may be mapped arbitrarily.
1710 starting_output_address(const Relobj
* object
, unsigned int shndx
) const;
1712 // Write the section header into *OPHDR.
1713 template<int size
, bool big_endian
>
1715 write_header(const Layout
*, const Stringpool
*,
1716 elfcpp::Shdr_write
<size
, big_endian
>*) const;
1718 // Print merge statistics to stderr.
1720 print_merge_stats();
1723 // Return the section index in the output file.
1725 do_out_shndx() const
1727 gold_assert(this->out_shndx_
!= -1U);
1728 return this->out_shndx_
;
1731 // Set the output section index.
1733 do_set_out_shndx(unsigned int shndx
)
1735 gold_assert(this->out_shndx_
== -1U);
1736 this->out_shndx_
= shndx
;
1739 // Set the final data size of the Output_section. For a typical
1740 // Output_section, there is nothing to do, but if there are any
1741 // Output_section_data objects we need to set their final addresses
1744 set_final_data_size();
1746 // Write the data to the file. For a typical Output_section, this
1747 // does nothing: the data is written out by calling Object::Relocate
1748 // on each input object. But if there are any Output_section_data
1749 // objects we do need to write them out here.
1751 do_write(Output_file
*);
1753 // Return the address alignment--function required by parent class.
1755 do_addralign() const
1756 { return this->addralign_
; }
1758 // Return whether this is an Output_section.
1760 do_is_section() const
1763 // Return whether this is a section of the specified type.
1765 do_is_section_type(elfcpp::Elf_Word type
) const
1766 { return this->type_
== type
; }
1768 // Return whether the specified section flag is set.
1770 do_is_section_flag_set(elfcpp::Elf_Xword flag
) const
1771 { return (this->flags_
& flag
) != 0; }
1773 // Set the TLS offset. Called only for SHT_TLS sections.
1775 do_set_tls_offset(uint64_t tls_base
);
1777 // Return the TLS offset, relative to the base of the TLS segment.
1778 // Valid only for SHT_TLS sections.
1780 do_tls_offset() const
1781 { return this->tls_offset_
; }
1783 // Modify the section name. This is only permitted for an
1784 // unallocated section, and only before the size has been finalized.
1785 // Otherwise the name will not get into Layout::namepool_.
1787 set_name(const char* newname
)
1789 gold_assert((this->flags_
& elfcpp::SHF_ALLOC
) == 0);
1790 gold_assert(!this->is_data_size_valid());
1791 this->name_
= newname
;
1794 // This may be implemented by a child class.
1796 do_finalize_name(Layout
*)
1799 // Record that this section requires postprocessing after all
1800 // relocations have been applied. This is called by a child class.
1802 set_requires_postprocessing()
1804 this->requires_postprocessing_
= true;
1805 this->after_input_sections_
= true;
1808 // Write all the data of an Output_section into the postprocessing
1811 write_to_postprocessing_buffer();
1814 // In some cases we need to keep a list of the input sections
1815 // associated with this output section. We only need the list if we
1816 // might have to change the offsets of the input section within the
1817 // output section after we add the input section. The ordinary
1818 // input sections will be written out when we process the object
1819 // file, and as such we don't need to track them here. We do need
1820 // to track Output_section_data objects here. We store instances of
1821 // this structure in a std::vector, so it must be a POD. There can
1822 // be many instances of this structure, so we use a union to save
1828 : shndx_(0), p2align_(0)
1830 this->u1_
.data_size
= 0;
1831 this->u2_
.object
= NULL
;
1834 // For an ordinary input section.
1835 Input_section(Relobj
* object
, unsigned int shndx
, off_t data_size
,
1838 p2align_(ffsll(static_cast<long long>(addralign
)))
1840 gold_assert(shndx
!= OUTPUT_SECTION_CODE
1841 && shndx
!= MERGE_DATA_SECTION_CODE
1842 && shndx
!= MERGE_STRING_SECTION_CODE
);
1843 this->u1_
.data_size
= data_size
;
1844 this->u2_
.object
= object
;
1847 // For a non-merge output section.
1848 Input_section(Output_section_data
* posd
)
1849 : shndx_(OUTPUT_SECTION_CODE
),
1850 p2align_(ffsll(static_cast<long long>(posd
->addralign())))
1852 this->u1_
.data_size
= 0;
1853 this->u2_
.posd
= posd
;
1856 // For a merge section.
1857 Input_section(Output_section_data
* posd
, bool is_string
, uint64_t entsize
)
1859 ? MERGE_STRING_SECTION_CODE
1860 : MERGE_DATA_SECTION_CODE
),
1861 p2align_(ffsll(static_cast<long long>(posd
->addralign())))
1863 this->u1_
.entsize
= entsize
;
1864 this->u2_
.posd
= posd
;
1867 // The required alignment.
1871 return (this->p2align_
== 0
1873 : static_cast<uint64_t>(1) << (this->p2align_
- 1));
1876 // Return the required size.
1880 // Return whether this is a merge section which matches the
1883 is_merge_section(bool is_string
, uint64_t entsize
,
1884 uint64_t addralign
) const
1886 return (this->shndx_
== (is_string
1887 ? MERGE_STRING_SECTION_CODE
1888 : MERGE_DATA_SECTION_CODE
)
1889 && this->u1_
.entsize
== entsize
1890 && this->addralign() == addralign
);
1893 // Set the output section.
1895 set_output_section(Output_section
* os
)
1897 gold_assert(!this->is_input_section());
1898 this->u2_
.posd
->set_output_section(os
);
1901 // Set the address and file offset. This is called during
1902 // Layout::finalize. SECTION_FILE_OFFSET is the file offset of
1903 // the enclosing section.
1905 set_address_and_file_offset(uint64_t address
, off_t file_offset
,
1906 off_t section_file_offset
);
1908 // Finalize the data size.
1910 finalize_data_size();
1912 // Add an input section, for SHF_MERGE sections.
1914 add_input_section(Relobj
* object
, unsigned int shndx
)
1916 gold_assert(this->shndx_
== MERGE_DATA_SECTION_CODE
1917 || this->shndx_
== MERGE_STRING_SECTION_CODE
);
1918 return this->u2_
.posd
->add_input_section(object
, shndx
);
1921 // Given an input OBJECT, an input section index SHNDX within that
1922 // object, and an OFFSET relative to the start of that input
1923 // section, return whether or not the output offset is known. If
1924 // this function returns true, it sets *POUTPUT to the offset in
1925 // the output section, relative to the start of the input section
1926 // in the output section. *POUTPUT may be different from OFFSET
1927 // for a merged section.
1929 output_offset(const Relobj
* object
, unsigned int shndx
,
1930 section_offset_type offset
,
1931 section_offset_type
*poutput
) const;
1933 // Return whether this is the merge section for the input section
1936 is_merge_section_for(const Relobj
* object
, unsigned int shndx
) const;
1938 // Write out the data. This does nothing for an input section.
1940 write(Output_file
*);
1942 // Write the data to a buffer. This does nothing for an input
1945 write_to_buffer(unsigned char*);
1947 // Print statistics about merge sections to stderr.
1949 print_merge_stats(const char* section_name
)
1951 if (this->shndx_
== MERGE_DATA_SECTION_CODE
1952 || this->shndx_
== MERGE_STRING_SECTION_CODE
)
1953 this->u2_
.posd
->print_merge_stats(section_name
);
1957 // Code values which appear in shndx_. If the value is not one of
1958 // these codes, it is the input section index in the object file.
1961 // An Output_section_data.
1962 OUTPUT_SECTION_CODE
= -1U,
1963 // An Output_section_data for an SHF_MERGE section with
1964 // SHF_STRINGS not set.
1965 MERGE_DATA_SECTION_CODE
= -2U,
1966 // An Output_section_data for an SHF_MERGE section with
1968 MERGE_STRING_SECTION_CODE
= -3U
1971 // Whether this is an input section.
1973 is_input_section() const
1975 return (this->shndx_
!= OUTPUT_SECTION_CODE
1976 && this->shndx_
!= MERGE_DATA_SECTION_CODE
1977 && this->shndx_
!= MERGE_STRING_SECTION_CODE
);
1980 // For an ordinary input section, this is the section index in the
1981 // input file. For an Output_section_data, this is
1982 // OUTPUT_SECTION_CODE or MERGE_DATA_SECTION_CODE or
1983 // MERGE_STRING_SECTION_CODE.
1984 unsigned int shndx_
;
1985 // The required alignment, stored as a power of 2.
1986 unsigned int p2align_
;
1989 // For an ordinary input section, the section size.
1991 // For OUTPUT_SECTION_CODE, this is not used. For
1992 // MERGE_DATA_SECTION_CODE or MERGE_STRING_SECTION_CODE, the
1998 // For an ordinary input section, the object which holds the
2001 // For OUTPUT_SECTION_CODE or MERGE_DATA_SECTION_CODE or
2002 // MERGE_STRING_SECTION_CODE, the data.
2003 Output_section_data
* posd
;
2007 typedef std::vector
<Input_section
> Input_section_list
;
2009 // Fill data. This is used to fill in data between input sections.
2010 // When we have to keep track of the input sections, we can use an
2011 // Output_data_const, but we don't want to have to keep track of
2012 // input sections just to implement fills. For a fill we record the
2013 // offset, and the actual data to be written out.
2017 Fill(off_t section_offset
, off_t length
)
2018 : section_offset_(section_offset
), length_(length
)
2021 // Return section offset.
2023 section_offset() const
2024 { return this->section_offset_
; }
2026 // Return fill length.
2029 { return this->length_
; }
2032 // The offset within the output section.
2033 off_t section_offset_
;
2034 // The length of the space to fill.
2038 typedef std::vector
<Fill
> Fill_list
;
2040 // Add a new output section by Input_section.
2042 add_output_section_data(Input_section
*);
2044 // Add an SHF_MERGE input section. Returns true if the section was
2047 add_merge_input_section(Relobj
* object
, unsigned int shndx
, uint64_t flags
,
2048 uint64_t entsize
, uint64_t addralign
);
2050 // Add an output SHF_MERGE section POSD to this output section.
2051 // IS_STRING indicates whether it is a SHF_STRINGS section, and
2052 // ENTSIZE is the entity size. This returns the entry added to
2055 add_output_merge_section(Output_section_data
* posd
, bool is_string
,
2058 // Most of these fields are only valid after layout.
2060 // The name of the section. This will point into a Stringpool.
2062 // The section address is in the parent class.
2063 // The section alignment.
2064 uint64_t addralign_
;
2065 // The section entry size.
2067 // The file offset is in the parent class.
2068 // Set the section link field to the index of this section.
2069 const Output_data
* link_section_
;
2070 // If link_section_ is NULL, this is the link field.
2072 // Set the section info field to the index of this section.
2073 const Output_data
* info_section_
;
2074 // If info_section_ is NULL, this is the section info field.
2076 // The section type.
2077 const elfcpp::Elf_Word type_
;
2078 // The section flags.
2079 const elfcpp::Elf_Xword flags_
;
2080 // The section index.
2081 unsigned int out_shndx_
;
2082 // If there is a STT_SECTION for this output section in the normal
2083 // symbol table, this is the symbol index. This starts out as zero.
2084 // It is initialized in Layout::finalize() to be the index, or -1U
2085 // if there isn't one.
2086 unsigned int symtab_index_
;
2087 // If there is a STT_SECTION for this output section in the dynamic
2088 // symbol table, this is the symbol index. This starts out as zero.
2089 // It is initialized in Layout::finalize() to be the index, or -1U
2090 // if there isn't one.
2091 unsigned int dynsym_index_
;
2092 // The input sections. This will be empty in cases where we don't
2093 // need to keep track of them.
2094 Input_section_list input_sections_
;
2095 // The offset of the first entry in input_sections_.
2096 off_t first_input_offset_
;
2097 // The fill data. This is separate from input_sections_ because we
2098 // often will need fill sections without needing to keep track of
2101 // If the section requires postprocessing, this buffer holds the
2102 // section contents during relocation.
2103 unsigned char* postprocessing_buffer_
;
2104 // Whether this output section needs a STT_SECTION symbol in the
2105 // normal symbol table. This will be true if there is a relocation
2107 bool needs_symtab_index_
: 1;
2108 // Whether this output section needs a STT_SECTION symbol in the
2109 // dynamic symbol table. This will be true if there is a dynamic
2110 // relocation which needs it.
2111 bool needs_dynsym_index_
: 1;
2112 // Whether the link field of this output section should point to the
2113 // normal symbol table.
2114 bool should_link_to_symtab_
: 1;
2115 // Whether the link field of this output section should point to the
2116 // dynamic symbol table.
2117 bool should_link_to_dynsym_
: 1;
2118 // Whether this section should be written after all the input
2119 // sections are complete.
2120 bool after_input_sections_
: 1;
2121 // Whether this section requires post processing after all
2122 // relocations have been applied.
2123 bool requires_postprocessing_
: 1;
2124 // For SHT_TLS sections, the offset of this section relative to the base
2125 // of the TLS segment.
2126 uint64_t tls_offset_
;
2129 // An output segment. PT_LOAD segments are built from collections of
2130 // output sections. Other segments typically point within PT_LOAD
2131 // segments, and are built directly as needed.
2133 class Output_segment
2136 // Create an output segment, specifying the type and flags.
2137 Output_segment(elfcpp::Elf_Word
, elfcpp::Elf_Word
);
2139 // Return the virtual address.
2142 { return this->vaddr_
; }
2144 // Return the physical address.
2147 { return this->paddr_
; }
2149 // Return the segment type.
2152 { return this->type_
; }
2154 // Return the segment flags.
2157 { return this->flags_
; }
2159 // Return the memory size.
2162 { return this->memsz_
; }
2164 // Return the file size.
2167 { return this->filesz_
; }
2169 // Return the maximum alignment of the Output_data.
2173 // Add an Output_section to this segment.
2175 add_output_section(Output_section
* os
, elfcpp::Elf_Word seg_flags
)
2176 { this->add_output_section(os
, seg_flags
, false); }
2178 // Add an Output_section to the start of this segment.
2180 add_initial_output_section(Output_section
* os
, elfcpp::Elf_Word seg_flags
)
2181 { this->add_output_section(os
, seg_flags
, true); }
2183 // Add an Output_data (which is not an Output_section) to the start
2186 add_initial_output_data(Output_data
*);
2188 // Return the number of dynamic relocations applied to this segment.
2190 dynamic_reloc_count() const;
2192 // Set the address of the segment to ADDR and the offset to *POFF
2193 // (aligned if necessary), and set the addresses and offsets of all
2194 // contained output sections accordingly. Set the section indexes
2195 // of all contained output sections starting with *PSHNDX. Return
2196 // the address of the immediately following segment. Update *POFF
2197 // and *PSHNDX. This should only be called for a PT_LOAD segment.
2199 set_section_addresses(uint64_t addr
, off_t
* poff
, unsigned int* pshndx
);
2201 // Set the minimum alignment of this segment. This may be adjusted
2202 // upward based on the section alignments.
2204 set_minimum_addralign(uint64_t align
)
2206 gold_assert(!this->is_align_known_
);
2207 this->align_
= align
;
2210 // Set the offset of this segment based on the section. This should
2211 // only be called for a non-PT_LOAD segment.
2215 // Set the TLS offsets of the sections contained in the PT_TLS segment.
2219 // Return the number of output sections.
2221 output_section_count() const;
2223 // Write the segment header into *OPHDR.
2224 template<int size
, bool big_endian
>
2226 write_header(elfcpp::Phdr_write
<size
, big_endian
>*);
2228 // Write the section headers of associated sections into V.
2229 template<int size
, bool big_endian
>
2231 write_section_headers(const Layout
*, const Stringpool
*, unsigned char* v
,
2232 unsigned int* pshndx ACCEPT_SIZE_ENDIAN
) const;
2235 Output_segment(const Output_segment
&);
2236 Output_segment
& operator=(const Output_segment
&);
2238 typedef std::list
<Output_data
*> Output_data_list
;
2240 // Add an Output_section to this segment, specifying front or back.
2242 add_output_section(Output_section
*, elfcpp::Elf_Word seg_flags
,
2245 // Find the maximum alignment in an Output_data_list.
2247 maximum_alignment(const Output_data_list
*);
2249 // Set the section addresses in an Output_data_list.
2251 set_section_list_addresses(Output_data_list
*, uint64_t addr
, off_t
* poff
,
2252 unsigned int* pshndx
);
2254 // Return the number of Output_sections in an Output_data_list.
2256 output_section_count_list(const Output_data_list
*) const;
2258 // Return the number of dynamic relocs in an Output_data_list.
2260 dynamic_reloc_count_list(const Output_data_list
*) const;
2262 // Write the section headers in the list into V.
2263 template<int size
, bool big_endian
>
2265 write_section_headers_list(const Layout
*, const Stringpool
*,
2266 const Output_data_list
*, unsigned char* v
,
2267 unsigned int* pshdx ACCEPT_SIZE_ENDIAN
) const;
2269 // The list of output data with contents attached to this segment.
2270 Output_data_list output_data_
;
2271 // The list of output data without contents attached to this segment.
2272 Output_data_list output_bss_
;
2273 // The segment virtual address.
2275 // The segment physical address.
2277 // The size of the segment in memory.
2279 // The segment alignment. The is_align_known_ field indicates
2280 // whether this has been finalized. It can be set to a minimum
2281 // value before it is finalized.
2283 // The offset of the segment data within the file.
2285 // The size of the segment data in the file.
2287 // The segment type;
2288 elfcpp::Elf_Word type_
;
2289 // The segment flags.
2290 elfcpp::Elf_Word flags_
;
2291 // Whether we have finalized align_.
2292 bool is_align_known_
;
2295 // This class represents the output file.
2300 Output_file(const General_options
& options
, Target
*);
2302 // Get a pointer to the target.
2305 { return this->target_
; }
2307 // Open the output file. FILE_SIZE is the final size of the file.
2309 open(off_t file_size
);
2311 // Resize the output file.
2313 resize(off_t file_size
);
2315 // Close the output file (flushing all buffered data) and make sure
2316 // there are no errors.
2320 // We currently always use mmap which makes the view handling quite
2321 // simple. In the future we may support other approaches.
2323 // Write data to the output file.
2325 write(off_t offset
, const void* data
, size_t len
)
2326 { memcpy(this->base_
+ offset
, data
, len
); }
2328 // Get a buffer to use to write to the file, given the offset into
2329 // the file and the size.
2331 get_output_view(off_t start
, size_t size
)
2333 gold_assert(start
>= 0
2334 && start
+ static_cast<off_t
>(size
) <= this->file_size_
);
2335 return this->base_
+ start
;
2338 // VIEW must have been returned by get_output_view. Write the
2339 // buffer to the file, passing in the offset and the size.
2341 write_output_view(off_t
, size_t, unsigned char*)
2344 // Get a read/write buffer. This is used when we want to write part
2345 // of the file, read it in, and write it again.
2347 get_input_output_view(off_t start
, size_t size
)
2348 { return this->get_output_view(start
, size
); }
2350 // Write a read/write buffer back to the file.
2352 write_input_output_view(off_t
, size_t, unsigned char*)
2355 // Get a read buffer. This is used when we just want to read part
2356 // of the file back it in.
2357 const unsigned char*
2358 get_input_view(off_t start
, size_t size
)
2359 { return this->get_output_view(start
, size
); }
2361 // Release a read bfufer.
2363 free_input_view(off_t
, size_t, const unsigned char*)
2367 // Map the file into memory and return a pointer to the map.
2371 // Unmap the file from memory (and flush to disk buffers).
2377 const General_options
& options_
;
2386 // Base of file mapped into memory.
2387 unsigned char* base_
;
2388 // True iff base_ points to a memory buffer rather than an output file.
2389 bool map_is_anonymous_
;
2392 } // End namespace gold.
2394 #endif // !defined(GOLD_OUTPUT_H)