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_
; }
202 // Functions that child classes may or in some cases must implement.
204 // Write the data to the output file.
206 do_write(Output_file
*) = 0;
208 // Return the required alignment.
210 do_addralign() const = 0;
212 // Return whether this is an Output_section.
214 do_is_section() const
217 // Return whether this is an Output_section of the specified type.
218 // This only needs to be implement by Output_section.
220 do_is_section_type(elfcpp::Elf_Word
) const
223 // Return whether this is an Output_section with the specific flag
224 // set. This only needs to be implemented by Output_section.
226 do_is_section_flag_set(elfcpp::Elf_Xword
) const
229 // Return the output section index, if there is an output section.
232 { gold_unreachable(); }
234 // Set the output section index, if this is an output section.
236 do_set_out_shndx(unsigned int)
237 { gold_unreachable(); }
239 // This is a hook for derived classes to set the data size. This is
240 // called by finalize_data_size, normally called during
241 // Layout::finalize, when the section address is set.
243 set_final_data_size()
244 { gold_unreachable(); }
246 // Set the TLS offset. Called only for SHT_TLS sections.
248 do_set_tls_offset(uint64_t)
249 { gold_unreachable(); }
251 // Return the TLS offset, relative to the base of the TLS segment.
252 // Valid only for SHT_TLS sections.
254 do_tls_offset() const
255 { gold_unreachable(); }
257 // Functions that child classes may call.
259 // Whether the address is valid.
261 is_address_valid() const
262 { return this->is_address_valid_
; }
264 // Whether the file offset is valid.
266 is_offset_valid() const
267 { return this->is_offset_valid_
; }
269 // Whether the data size is valid.
271 is_data_size_valid() const
272 { return this->is_data_size_valid_
; }
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
*);
398 // Add information about the section headers. We lay out the ELF
399 // file header before we create the section headers.
400 void set_section_info(const Output_section_headers
*,
401 const Output_section
* shstrtab
);
404 // Write the data to the file.
406 do_write(Output_file
*);
408 // Return the required alignment.
411 { return Output_data::default_alignment(); }
414 // Write the data to the file with the right size and endianness.
415 template<int size
, bool big_endian
>
417 do_sized_write(Output_file
*);
419 const Target
* target_
;
420 const Symbol_table
* symtab_
;
421 const Output_segment_headers
* segment_header_
;
422 const Output_section_headers
* section_header_
;
423 const Output_section
* shstrtab_
;
426 // Output sections are mainly comprised of input sections. However,
427 // there are cases where we have data to write out which is not in an
428 // input section. Output_section_data is used in such cases. This is
429 // an abstract base class.
431 class Output_section_data
: public Output_data
434 Output_section_data(off_t data_size
, uint64_t addralign
)
435 : Output_data(), output_section_(NULL
), addralign_(addralign
)
436 { this->set_data_size(data_size
); }
438 Output_section_data(uint64_t addralign
)
439 : Output_data(), output_section_(NULL
), addralign_(addralign
)
442 // Return the output section.
443 const Output_section
*
444 output_section() const
445 { return this->output_section_
; }
447 // Record the output section.
449 set_output_section(Output_section
* os
);
451 // Add an input section, for SHF_MERGE sections. This returns true
452 // if the section was handled.
454 add_input_section(Relobj
* object
, unsigned int shndx
)
455 { return this->do_add_input_section(object
, shndx
); }
457 // Given an input OBJECT, an input section index SHNDX within that
458 // object, and an OFFSET relative to the start of that input
459 // section, return whether or not the corresponding offset within
460 // the output section is known. If this function returns true, it
461 // sets *POUTPUT to the output offset. The value -1 indicates that
462 // this input offset is being discarded.
464 output_offset(const Relobj
* object
, unsigned int shndx
,
465 section_offset_type offset
,
466 section_offset_type
*poutput
) const
467 { return this->do_output_offset(object
, shndx
, offset
, poutput
); }
469 // Write the contents to a buffer. This is used for sections which
470 // require postprocessing, such as compression.
472 write_to_buffer(unsigned char* buffer
)
473 { this->do_write_to_buffer(buffer
); }
475 // Print merge stats to stderr. This should only be called for
476 // SHF_MERGE sections.
478 print_merge_stats(const char* section_name
)
479 { this->do_print_merge_stats(section_name
); }
482 // The child class must implement do_write.
484 // The child class may implement specific adjustments to the output
487 do_adjust_output_section(Output_section
*)
490 // May be implemented by child class. Return true if the section
493 do_add_input_section(Relobj
*, unsigned int)
494 { gold_unreachable(); }
496 // The child class may implement output_offset.
498 do_output_offset(const Relobj
*, unsigned int, section_offset_type
,
499 section_offset_type
*) const
502 // The child class may implement write_to_buffer. Most child
503 // classes can not appear in a compressed section, and they do not
506 do_write_to_buffer(unsigned char*)
507 { gold_unreachable(); }
509 // Print merge statistics.
511 do_print_merge_stats(const char*)
512 { gold_unreachable(); }
514 // Return the required alignment.
517 { return this->addralign_
; }
519 // Return the section index of the output section.
521 do_out_shndx() const;
523 // Set the alignment.
525 set_addralign(uint64_t addralign
)
526 { this->addralign_
= addralign
; }
529 // The output section for this section.
530 const Output_section
* output_section_
;
531 // The required alignment.
535 // Some Output_section_data classes build up their data step by step,
536 // rather than all at once. This class provides an interface for
539 class Output_section_data_build
: public Output_section_data
542 Output_section_data_build(uint64_t addralign
)
543 : Output_section_data(addralign
)
546 // Get the current data size.
548 current_data_size() const
549 { return this->current_data_size_for_child(); }
551 // Set the current data size.
553 set_current_data_size(off_t data_size
)
554 { this->set_current_data_size_for_child(data_size
); }
557 // Set the final data size.
559 set_final_data_size()
560 { this->set_data_size(this->current_data_size_for_child()); }
563 // A simple case of Output_data in which we have constant data to
566 class Output_data_const
: public Output_section_data
569 Output_data_const(const std::string
& data
, uint64_t addralign
)
570 : Output_section_data(data
.size(), addralign
), data_(data
)
573 Output_data_const(const char* p
, off_t len
, uint64_t addralign
)
574 : Output_section_data(len
, addralign
), data_(p
, len
)
577 Output_data_const(const unsigned char* p
, off_t len
, uint64_t addralign
)
578 : Output_section_data(len
, addralign
),
579 data_(reinterpret_cast<const char*>(p
), len
)
583 // Write the data to the output file.
585 do_write(Output_file
*);
587 // Write the data to a buffer.
589 do_write_to_buffer(unsigned char* buffer
)
590 { memcpy(buffer
, this->data_
.data(), this->data_
.size()); }
596 // Another version of Output_data with constant data, in which the
597 // buffer is allocated by the caller.
599 class Output_data_const_buffer
: public Output_section_data
602 Output_data_const_buffer(const unsigned char* p
, off_t len
,
604 : Output_section_data(len
, addralign
), p_(p
)
608 // Write the data the output file.
610 do_write(Output_file
*);
612 // Write the data to a buffer.
614 do_write_to_buffer(unsigned char* buffer
)
615 { memcpy(buffer
, this->p_
, this->data_size()); }
618 const unsigned char* p_
;
621 // A place holder for a fixed amount of data written out via some
624 class Output_data_fixed_space
: public Output_section_data
627 Output_data_fixed_space(off_t data_size
, uint64_t addralign
)
628 : Output_section_data(data_size
, addralign
)
632 // Write out the data--the actual data must be written out
635 do_write(Output_file
*)
639 // A place holder for variable sized data written out via some other
642 class Output_data_space
: public Output_section_data_build
645 explicit Output_data_space(uint64_t addralign
)
646 : Output_section_data_build(addralign
)
649 // Set the alignment.
651 set_space_alignment(uint64_t align
)
652 { this->set_addralign(align
); }
655 // Write out the data--the actual data must be written out
658 do_write(Output_file
*)
662 // A string table which goes into an output section.
664 class Output_data_strtab
: public Output_section_data
667 Output_data_strtab(Stringpool
* strtab
)
668 : Output_section_data(1), strtab_(strtab
)
672 // This is called to set the address and file offset. Here we make
673 // sure that the Stringpool is finalized.
675 set_final_data_size();
677 // Write out the data.
679 do_write(Output_file
*);
681 // Write the data to a buffer.
683 do_write_to_buffer(unsigned char* buffer
)
684 { this->strtab_
->write_to_buffer(buffer
, this->data_size()); }
690 // This POD class is used to represent a single reloc in the output
691 // file. This could be a private class within Output_data_reloc, but
692 // the templatization is complex enough that I broke it out into a
693 // separate class. The class is templatized on either elfcpp::SHT_REL
694 // or elfcpp::SHT_RELA, and also on whether this is a dynamic
695 // relocation or an ordinary relocation.
697 // A relocation can be against a global symbol, a local symbol, an
698 // output section, or the undefined symbol at index 0. We represent
699 // the latter by using a NULL global symbol.
701 template<int sh_type
, bool dynamic
, int size
, bool big_endian
>
704 template<bool dynamic
, int size
, bool big_endian
>
705 class Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>
708 typedef typename
elfcpp::Elf_types
<size
>::Elf_Addr Address
;
710 // An uninitialized entry. We need this because we want to put
711 // instances of this class into an STL container.
713 : local_sym_index_(INVALID_CODE
)
716 // A reloc against a global symbol.
718 Output_reloc(Symbol
* gsym
, unsigned int type
, Output_data
* od
,
719 Address address
, bool is_relative
);
721 Output_reloc(Symbol
* gsym
, unsigned int type
, Relobj
* relobj
,
722 unsigned int shndx
, Address address
, bool is_relative
);
724 // A reloc against a local symbol.
726 Output_reloc(Sized_relobj
<size
, big_endian
>* relobj
,
727 unsigned int local_sym_index
, unsigned int type
,
728 Output_data
* od
, Address address
, bool is_relative
);
730 Output_reloc(Sized_relobj
<size
, big_endian
>* relobj
,
731 unsigned int local_sym_index
, unsigned int type
,
732 unsigned int shndx
, Address address
, bool is_relative
);
734 // A reloc against the STT_SECTION symbol of an output section.
736 Output_reloc(Output_section
* os
, unsigned int type
, Output_data
* od
,
739 Output_reloc(Output_section
* os
, unsigned int type
, Relobj
* relobj
,
740 unsigned int shndx
, Address address
);
742 // Return TRUE if this is a RELATIVE relocation.
745 { return this->is_relative_
; }
747 // Get the value of the symbol referred to by a Rel relocation.
750 symbol_value() const;
752 // Write the reloc entry to an output view.
754 write(unsigned char* pov
) const;
756 // Write the offset and info fields to Write_rel.
757 template<typename Write_rel
>
758 void write_rel(Write_rel
*) const;
761 // Return the symbol index. We can't do a double template
762 // specialization, so we do a secondary template here.
764 get_symbol_index() const;
766 // Codes for local_sym_index_.
773 // Invalid uninitialized entry.
779 // For a local symbol, the object. We will never generate a
780 // relocation against a local symbol in a dynamic object; that
781 // doesn't make sense. And our callers will always be
782 // templatized, so we use Sized_relobj here.
783 Sized_relobj
<size
, big_endian
>* relobj
;
784 // For a global symbol, the symbol. If this is NULL, it indicates
785 // a relocation against the undefined 0 symbol.
787 // For a relocation against an output section, the output section.
792 // If shndx_ is not INVALID CODE, the object which holds the input
793 // section being used to specify the reloc address.
795 // If shndx_ is INVALID_CODE, the output data being used to
796 // specify the reloc address. This may be NULL if the reloc
797 // address is absolute.
800 // The address offset within the input section or the Output_data.
802 // For a local symbol, the local symbol index. This is GSYM_CODE
803 // for a global symbol, or INVALID_CODE for an uninitialized value.
804 unsigned int local_sym_index_
;
805 // The reloc type--a processor specific code.
806 unsigned int type_
: 31;
807 // True if the relocation is a RELATIVE relocation.
808 bool is_relative_
: 1;
809 // If the reloc address is an input section in an object, the
810 // section index. This is INVALID_CODE if the reloc address is
811 // specified in some other way.
815 // The SHT_RELA version of Output_reloc<>. This is just derived from
816 // the SHT_REL version of Output_reloc, but it adds an addend.
818 template<bool dynamic
, int size
, bool big_endian
>
819 class Output_reloc
<elfcpp::SHT_RELA
, dynamic
, size
, big_endian
>
822 typedef typename
elfcpp::Elf_types
<size
>::Elf_Addr Address
;
823 typedef typename
elfcpp::Elf_types
<size
>::Elf_Addr Addend
;
825 // An uninitialized entry.
830 // A reloc against a global symbol.
832 Output_reloc(Symbol
* gsym
, unsigned int type
, Output_data
* od
,
833 Address address
, Addend addend
, bool is_relative
)
834 : rel_(gsym
, type
, od
, address
, is_relative
), addend_(addend
)
837 Output_reloc(Symbol
* gsym
, unsigned int type
, Relobj
* relobj
,
838 unsigned int shndx
, Address address
, Addend addend
,
840 : rel_(gsym
, type
, relobj
, shndx
, address
, is_relative
), addend_(addend
)
843 // A reloc against a local symbol.
845 Output_reloc(Sized_relobj
<size
, big_endian
>* relobj
,
846 unsigned int local_sym_index
, unsigned int type
,
847 Output_data
* od
, Address address
,
848 Addend addend
, bool is_relative
)
849 : rel_(relobj
, local_sym_index
, type
, od
, address
, is_relative
),
853 Output_reloc(Sized_relobj
<size
, big_endian
>* relobj
,
854 unsigned int local_sym_index
, unsigned int type
,
855 unsigned int shndx
, Address address
,
856 Addend addend
, bool is_relative
)
857 : rel_(relobj
, local_sym_index
, type
, shndx
, address
, is_relative
),
861 // A reloc against the STT_SECTION symbol of an output section.
863 Output_reloc(Output_section
* os
, unsigned int type
, Output_data
* od
,
864 Address address
, Addend addend
)
865 : rel_(os
, type
, od
, address
), addend_(addend
)
868 Output_reloc(Output_section
* os
, unsigned int type
, Relobj
* relobj
,
869 unsigned int shndx
, Address address
, Addend addend
)
870 : rel_(os
, type
, relobj
, shndx
, address
), addend_(addend
)
873 // Write the reloc entry to an output view.
875 write(unsigned char* pov
) const;
879 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
> rel_
;
884 // Output_data_reloc is used to manage a section containing relocs.
885 // SH_TYPE is either elfcpp::SHT_REL or elfcpp::SHT_RELA. DYNAMIC
886 // indicates whether this is a dynamic relocation or a normal
887 // relocation. Output_data_reloc_base is a base class.
888 // Output_data_reloc is the real class, which we specialize based on
891 template<int sh_type
, bool dynamic
, int size
, bool big_endian
>
892 class Output_data_reloc_base
: public Output_section_data_build
895 typedef Output_reloc
<sh_type
, dynamic
, size
, big_endian
> Output_reloc_type
;
896 typedef typename
Output_reloc_type::Address Address
;
897 static const int reloc_size
=
898 Reloc_types
<sh_type
, size
, big_endian
>::reloc_size
;
900 // Construct the section.
901 Output_data_reloc_base()
902 : Output_section_data_build(Output_data::default_alignment_for_size(size
))
906 // Write out the data.
908 do_write(Output_file
*);
910 // Set the entry size and the link.
912 do_adjust_output_section(Output_section
*os
);
914 // Add a relocation entry.
916 add(Output_data
*od
, const Output_reloc_type
& reloc
)
918 this->relocs_
.push_back(reloc
);
919 this->set_current_data_size(this->relocs_
.size() * reloc_size
);
920 od
->add_dynamic_reloc();
924 typedef std::vector
<Output_reloc_type
> Relocs
;
929 // The class which callers actually create.
931 template<int sh_type
, bool dynamic
, int size
, bool big_endian
>
932 class Output_data_reloc
;
934 // The SHT_REL version of Output_data_reloc.
936 template<bool dynamic
, int size
, bool big_endian
>
937 class Output_data_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>
938 : public Output_data_reloc_base
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>
941 typedef Output_data_reloc_base
<elfcpp::SHT_REL
, dynamic
, size
,
945 typedef typename
Base::Output_reloc_type Output_reloc_type
;
946 typedef typename
Output_reloc_type::Address Address
;
949 : Output_data_reloc_base
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>()
952 // Add a reloc against a global symbol.
955 add_global(Symbol
* gsym
, unsigned int type
, Output_data
* od
, Address address
)
956 { this->add(od
, Output_reloc_type(gsym
, type
, od
, address
, false)); }
959 add_global(Symbol
* gsym
, unsigned int type
, Output_data
* od
, Relobj
* relobj
,
960 unsigned int shndx
, Address address
)
961 { this->add(od
, Output_reloc_type(gsym
, type
, relobj
, shndx
, address
,
964 // Add a RELATIVE reloc against a global symbol. The final relocation
965 // will not reference the symbol.
968 add_global_relative(Symbol
* gsym
, unsigned int type
, Output_data
* od
,
970 { this->add(od
, Output_reloc_type(gsym
, type
, od
, address
, true)); }
973 add_global_relative(Symbol
* gsym
, unsigned int type
, Output_data
* od
,
974 Relobj
* relobj
, unsigned int shndx
, Address address
)
975 { this->add(od
, Output_reloc_type(gsym
, type
, relobj
, shndx
, address
,
978 // Add a reloc against a local symbol.
981 add_local(Sized_relobj
<size
, big_endian
>* relobj
,
982 unsigned int local_sym_index
, unsigned int type
,
983 Output_data
* od
, Address address
)
984 { this->add(od
, Output_reloc_type(relobj
, local_sym_index
, type
, od
,
988 add_local(Sized_relobj
<size
, big_endian
>* relobj
,
989 unsigned int local_sym_index
, unsigned int type
,
990 Output_data
* od
, unsigned int shndx
, Address address
)
991 { this->add(od
, Output_reloc_type(relobj
, local_sym_index
, type
, shndx
,
994 // Add a RELATIVE reloc against a local symbol.
997 add_local_relative(Sized_relobj
<size
, big_endian
>* relobj
,
998 unsigned int local_sym_index
, unsigned int type
,
999 Output_data
* od
, Address address
)
1000 { this->add(od
, Output_reloc_type(relobj
, local_sym_index
, type
, od
,
1004 add_local_relative(Sized_relobj
<size
, big_endian
>* relobj
,
1005 unsigned int local_sym_index
, unsigned int type
,
1006 Output_data
* od
, unsigned int shndx
, Address address
)
1007 { this->add(od
, Output_reloc_type(relobj
, local_sym_index
, type
, shndx
,
1010 // A reloc against the STT_SECTION symbol of an output section.
1011 // OS is the Output_section that the relocation refers to; OD is
1012 // the Output_data object being relocated.
1015 add_output_section(Output_section
* os
, unsigned int type
,
1016 Output_data
* od
, Address address
)
1017 { this->add(od
, Output_reloc_type(os
, type
, od
, address
)); }
1020 add_output_section(Output_section
* os
, unsigned int type
, Output_data
* od
,
1021 Relobj
* relobj
, unsigned int shndx
, Address address
)
1022 { this->add(od
, Output_reloc_type(os
, type
, relobj
, shndx
, address
)); }
1025 // The SHT_RELA version of Output_data_reloc.
1027 template<bool dynamic
, int size
, bool big_endian
>
1028 class Output_data_reloc
<elfcpp::SHT_RELA
, dynamic
, size
, big_endian
>
1029 : public Output_data_reloc_base
<elfcpp::SHT_RELA
, dynamic
, size
, big_endian
>
1032 typedef Output_data_reloc_base
<elfcpp::SHT_RELA
, dynamic
, size
,
1036 typedef typename
Base::Output_reloc_type Output_reloc_type
;
1037 typedef typename
Output_reloc_type::Address Address
;
1038 typedef typename
Output_reloc_type::Addend Addend
;
1041 : Output_data_reloc_base
<elfcpp::SHT_RELA
, dynamic
, size
, big_endian
>()
1044 // Add a reloc against a global symbol.
1047 add_global(Symbol
* gsym
, unsigned int type
, Output_data
* od
,
1048 Address address
, Addend addend
)
1049 { this->add(od
, Output_reloc_type(gsym
, type
, od
, address
, addend
,
1053 add_global(Symbol
* gsym
, unsigned int type
, Output_data
* od
, Relobj
* relobj
,
1054 unsigned int shndx
, Address address
,
1056 { this->add(od
, Output_reloc_type(gsym
, type
, relobj
, shndx
, address
,
1059 // Add a RELATIVE reloc against a global symbol. The final output
1060 // relocation will not reference the symbol, but we must keep the symbol
1061 // information long enough to set the addend of the relocation correctly
1062 // when it is written.
1065 add_global_relative(Symbol
* gsym
, unsigned int type
, Output_data
* od
,
1066 Address address
, Addend addend
)
1067 { this->add(od
, Output_reloc_type(gsym
, type
, od
, address
, addend
, true)); }
1070 add_global_relative(Symbol
* gsym
, unsigned int type
, Output_data
* od
,
1071 Relobj
* relobj
, unsigned int shndx
, Address address
,
1073 { this->add(od
, Output_reloc_type(gsym
, type
, relobj
, shndx
, address
,
1076 // Add a reloc against a local symbol.
1079 add_local(Sized_relobj
<size
, big_endian
>* relobj
,
1080 unsigned int local_sym_index
, unsigned int type
,
1081 Output_data
* od
, Address address
, Addend addend
)
1083 this->add(od
, Output_reloc_type(relobj
, local_sym_index
, type
, od
, address
,
1088 add_local(Sized_relobj
<size
, big_endian
>* relobj
,
1089 unsigned int local_sym_index
, unsigned int type
,
1090 Output_data
* od
, unsigned int shndx
, Address address
,
1093 this->add(od
, Output_reloc_type(relobj
, local_sym_index
, type
, shndx
,
1094 address
, addend
, false));
1097 // Add a RELATIVE reloc against a local symbol.
1100 add_local_relative(Sized_relobj
<size
, big_endian
>* relobj
,
1101 unsigned int local_sym_index
, unsigned int type
,
1102 Output_data
* od
, Address address
, Addend addend
)
1104 this->add(od
, Output_reloc_type(relobj
, local_sym_index
, type
, od
, address
,
1109 add_local_relative(Sized_relobj
<size
, big_endian
>* relobj
,
1110 unsigned int local_sym_index
, unsigned int type
,
1111 Output_data
* od
, unsigned int shndx
, Address address
,
1114 this->add(od
, Output_reloc_type(relobj
, local_sym_index
, type
, shndx
,
1115 address
, addend
, true));
1118 // A reloc against the STT_SECTION symbol of an output section.
1121 add_output_section(Output_section
* os
, unsigned int type
, Output_data
* od
,
1122 Address address
, Addend addend
)
1123 { this->add(os
, Output_reloc_type(os
, type
, od
, address
, addend
)); }
1126 add_output_section(Output_section
* os
, unsigned int type
, Relobj
* relobj
,
1127 unsigned int shndx
, Address address
, Addend addend
)
1128 { this->add(os
, Output_reloc_type(os
, type
, relobj
, shndx
, address
,
1132 // Output_data_got is used to manage a GOT. Each entry in the GOT is
1133 // for one symbol--either a global symbol or a local symbol in an
1134 // object. The target specific code adds entries to the GOT as
1137 template<int size
, bool big_endian
>
1138 class Output_data_got
: public Output_section_data_build
1141 typedef typename
elfcpp::Elf_types
<size
>::Elf_Addr Valtype
;
1142 typedef Output_data_reloc
<elfcpp::SHT_REL
, true, size
, big_endian
> Rel_dyn
;
1143 typedef Output_data_reloc
<elfcpp::SHT_RELA
, true, size
, big_endian
> Rela_dyn
;
1146 : Output_section_data_build(Output_data::default_alignment_for_size(size
)),
1150 // Add an entry for a global symbol to the GOT. Return true if this
1151 // is a new GOT entry, false if the symbol was already in the GOT.
1153 add_global(Symbol
* gsym
);
1155 // Add an entry for a global symbol to the GOT, and add a dynamic
1156 // relocation of type R_TYPE for the GOT entry.
1158 add_global_with_rel(Symbol
* gsym
, Rel_dyn
* rel_dyn
, unsigned int r_type
);
1161 add_global_with_rela(Symbol
* gsym
, Rela_dyn
* rela_dyn
, unsigned int r_type
);
1163 // Add an entry for a local symbol to the GOT. This returns true if
1164 // this is a new GOT entry, false if the symbol already has a GOT
1167 add_local(Sized_relobj
<size
, big_endian
>* object
, unsigned int sym_index
);
1169 // Add an entry for a global symbol to the GOT, and add a dynamic
1170 // relocation of type R_TYPE for the GOT entry.
1172 add_local_with_rel(Sized_relobj
<size
, big_endian
>* object
,
1173 unsigned int sym_index
, Rel_dyn
* rel_dyn
,
1174 unsigned int r_type
);
1177 add_local_with_rela(Sized_relobj
<size
, big_endian
>* object
,
1178 unsigned int sym_index
, Rela_dyn
* rela_dyn
,
1179 unsigned int r_type
);
1181 // Add an entry (or pair of entries) for a global TLS symbol to the GOT.
1182 // Return true if this is a new GOT entry, false if the symbol was
1183 // already in the GOT.
1185 add_global_tls(Symbol
* gsym
, bool need_pair
);
1187 // Add an entry for a global TLS symbol to the GOT, and add a dynamic
1188 // relocation of type R_TYPE.
1190 add_global_tls_with_rel(Symbol
* gsym
, Rel_dyn
* rel_dyn
,
1191 unsigned int r_type
);
1194 add_global_tls_with_rela(Symbol
* gsym
, Rela_dyn
* rela_dyn
,
1195 unsigned int r_type
);
1197 // Add a pair of entries for a global TLS symbol to the GOT, and add
1198 // dynamic relocations of type MOD_R_TYPE and DTV_R_TYPE, respectively.
1200 add_global_tls_with_rel(Symbol
* gsym
, Rel_dyn
* rel_dyn
,
1201 unsigned int mod_r_type
,
1202 unsigned int dtv_r_type
);
1205 add_global_tls_with_rela(Symbol
* gsym
, Rela_dyn
* rela_dyn
,
1206 unsigned int mod_r_type
,
1207 unsigned int dtv_r_type
);
1209 // Add an entry (or pair of entries) for a local TLS symbol to the GOT.
1210 // This returns true if this is a new GOT entry, false if the symbol
1211 // already has a GOT entry.
1213 add_local_tls(Sized_relobj
<size
, big_endian
>* object
,
1214 unsigned int sym_index
, bool need_pair
);
1216 // Add an entry (or pair of entries) for a local TLS symbol to the GOT,
1217 // and add a dynamic relocation of type R_TYPE for the first GOT entry.
1218 // Because this is a local symbol, the first GOT entry can be relocated
1219 // relative to a section symbol, and the second GOT entry will have an
1220 // dtv-relative value that can be computed at link time.
1222 add_local_tls_with_rel(Sized_relobj
<size
, big_endian
>* object
,
1223 unsigned int sym_index
, unsigned int shndx
,
1224 bool need_pair
, Rel_dyn
* rel_dyn
,
1225 unsigned int r_type
);
1228 add_local_tls_with_rela(Sized_relobj
<size
, big_endian
>* object
,
1229 unsigned int sym_index
, unsigned int shndx
,
1230 bool need_pair
, Rela_dyn
* rela_dyn
,
1231 unsigned int r_type
);
1233 // Add a constant to the GOT. This returns the offset of the new
1234 // entry from the start of the GOT.
1236 add_constant(Valtype constant
)
1238 this->entries_
.push_back(Got_entry(constant
));
1239 this->set_got_size();
1240 return this->last_got_offset();
1244 // Write out the GOT table.
1246 do_write(Output_file
*);
1249 // This POD class holds a single GOT entry.
1253 // Create a zero entry.
1255 : local_sym_index_(CONSTANT_CODE
)
1256 { this->u_
.constant
= 0; }
1258 // Create a global symbol entry.
1259 explicit Got_entry(Symbol
* gsym
)
1260 : local_sym_index_(GSYM_CODE
)
1261 { this->u_
.gsym
= gsym
; }
1263 // Create a local symbol entry.
1264 Got_entry(Sized_relobj
<size
, big_endian
>* object
,
1265 unsigned int local_sym_index
)
1266 : local_sym_index_(local_sym_index
)
1268 gold_assert(local_sym_index
!= GSYM_CODE
1269 && local_sym_index
!= CONSTANT_CODE
);
1270 this->u_
.object
= object
;
1273 // Create a constant entry. The constant is a host value--it will
1274 // be swapped, if necessary, when it is written out.
1275 explicit Got_entry(Valtype constant
)
1276 : local_sym_index_(CONSTANT_CODE
)
1277 { this->u_
.constant
= constant
; }
1279 // Write the GOT entry to an output view.
1281 write(unsigned char* pov
) const;
1292 // For a local symbol, the object.
1293 Sized_relobj
<size
, big_endian
>* object
;
1294 // For a global symbol, the symbol.
1296 // For a constant, the constant.
1299 // For a local symbol, the local symbol index. This is GSYM_CODE
1300 // for a global symbol, or CONSTANT_CODE for a constant.
1301 unsigned int local_sym_index_
;
1304 typedef std::vector
<Got_entry
> Got_entries
;
1306 // Return the offset into the GOT of GOT entry I.
1308 got_offset(unsigned int i
) const
1309 { return i
* (size
/ 8); }
1311 // Return the offset into the GOT of the last entry added.
1313 last_got_offset() const
1314 { return this->got_offset(this->entries_
.size() - 1); }
1316 // Set the size of the section.
1319 { this->set_current_data_size(this->got_offset(this->entries_
.size())); }
1321 // The list of GOT entries.
1322 Got_entries entries_
;
1325 // Output_data_dynamic is used to hold the data in SHT_DYNAMIC
1328 class Output_data_dynamic
: public Output_section_data
1331 Output_data_dynamic(Stringpool
* pool
)
1332 : Output_section_data(Output_data::default_alignment()),
1333 entries_(), pool_(pool
)
1336 // Add a new dynamic entry with a fixed numeric value.
1338 add_constant(elfcpp::DT tag
, unsigned int val
)
1339 { this->add_entry(Dynamic_entry(tag
, val
)); }
1341 // Add a new dynamic entry with the address of output data.
1343 add_section_address(elfcpp::DT tag
, const Output_data
* od
)
1344 { this->add_entry(Dynamic_entry(tag
, od
, false)); }
1346 // Add a new dynamic entry with the size of output data.
1348 add_section_size(elfcpp::DT tag
, const Output_data
* od
)
1349 { this->add_entry(Dynamic_entry(tag
, od
, true)); }
1351 // Add a new dynamic entry with the address of a symbol.
1353 add_symbol(elfcpp::DT tag
, const Symbol
* sym
)
1354 { this->add_entry(Dynamic_entry(tag
, sym
)); }
1356 // Add a new dynamic entry with a string.
1358 add_string(elfcpp::DT tag
, const char* str
)
1359 { this->add_entry(Dynamic_entry(tag
, this->pool_
->add(str
, true, NULL
))); }
1362 add_string(elfcpp::DT tag
, const std::string
& str
)
1363 { this->add_string(tag
, str
.c_str()); }
1366 // Adjust the output section to set the entry size.
1368 do_adjust_output_section(Output_section
*);
1370 // Set the final data size.
1372 set_final_data_size();
1374 // Write out the dynamic entries.
1376 do_write(Output_file
*);
1379 // This POD class holds a single dynamic entry.
1383 // Create an entry with a fixed numeric value.
1384 Dynamic_entry(elfcpp::DT tag
, unsigned int val
)
1385 : tag_(tag
), classification_(DYNAMIC_NUMBER
)
1386 { this->u_
.val
= val
; }
1388 // Create an entry with the size or address of a section.
1389 Dynamic_entry(elfcpp::DT tag
, const Output_data
* od
, bool section_size
)
1391 classification_(section_size
1392 ? DYNAMIC_SECTION_SIZE
1393 : DYNAMIC_SECTION_ADDRESS
)
1394 { this->u_
.od
= od
; }
1396 // Create an entry with the address of a symbol.
1397 Dynamic_entry(elfcpp::DT tag
, const Symbol
* sym
)
1398 : tag_(tag
), classification_(DYNAMIC_SYMBOL
)
1399 { this->u_
.sym
= sym
; }
1401 // Create an entry with a string.
1402 Dynamic_entry(elfcpp::DT tag
, const char* str
)
1403 : tag_(tag
), classification_(DYNAMIC_STRING
)
1404 { this->u_
.str
= str
; }
1406 // Write the dynamic entry to an output view.
1407 template<int size
, bool big_endian
>
1409 write(unsigned char* pov
, const Stringpool
* ACCEPT_SIZE_ENDIAN
) const;
1417 DYNAMIC_SECTION_ADDRESS
,
1419 DYNAMIC_SECTION_SIZE
,
1428 // For DYNAMIC_NUMBER.
1430 // For DYNAMIC_SECTION_ADDRESS and DYNAMIC_SECTION_SIZE.
1431 const Output_data
* od
;
1432 // For DYNAMIC_SYMBOL.
1434 // For DYNAMIC_STRING.
1439 // The type of entry.
1440 Classification classification_
;
1443 // Add an entry to the list.
1445 add_entry(const Dynamic_entry
& entry
)
1446 { this->entries_
.push_back(entry
); }
1448 // Sized version of write function.
1449 template<int size
, bool big_endian
>
1451 sized_write(Output_file
* of
);
1453 // The type of the list of entries.
1454 typedef std::vector
<Dynamic_entry
> Dynamic_entries
;
1457 Dynamic_entries entries_
;
1458 // The pool used for strings.
1462 // An output section. We don't expect to have too many output
1463 // sections, so we don't bother to do a template on the size.
1465 class Output_section
: public Output_data
1468 // Create an output section, giving the name, type, and flags.
1469 Output_section(const char* name
, elfcpp::Elf_Word
, elfcpp::Elf_Xword
);
1470 virtual ~Output_section();
1472 // Add a new input section SHNDX, named NAME, with header SHDR, from
1473 // object OBJECT. RELOC_SHNDX is the index of a relocation section
1474 // which applies to this section, or 0 if none, or -1U if more than
1475 // one. Return the offset within the output section.
1476 template<int size
, bool big_endian
>
1478 add_input_section(Sized_relobj
<size
, big_endian
>* object
, unsigned int shndx
,
1480 const elfcpp::Shdr
<size
, big_endian
>& shdr
,
1481 unsigned int reloc_shndx
);
1483 // Add generated data POSD to this output section.
1485 add_output_section_data(Output_section_data
* posd
);
1487 // Return the section name.
1490 { return this->name_
; }
1492 // Return the section type.
1495 { return this->type_
; }
1497 // Return the section flags.
1500 { return this->flags_
; }
1502 // Return the entsize field.
1505 { return this->entsize_
; }
1507 // Set the entsize field.
1509 set_entsize(uint64_t v
);
1511 // Set the link field to the output section index of a section.
1513 set_link_section(const Output_data
* od
)
1515 gold_assert(this->link_
== 0
1516 && !this->should_link_to_symtab_
1517 && !this->should_link_to_dynsym_
);
1518 this->link_section_
= od
;
1521 // Set the link field to a constant.
1523 set_link(unsigned int v
)
1525 gold_assert(this->link_section_
== NULL
1526 && !this->should_link_to_symtab_
1527 && !this->should_link_to_dynsym_
);
1531 // Record that this section should link to the normal symbol table.
1533 set_should_link_to_symtab()
1535 gold_assert(this->link_section_
== NULL
1537 && !this->should_link_to_dynsym_
);
1538 this->should_link_to_symtab_
= true;
1541 // Record that this section should link to the dynamic symbol table.
1543 set_should_link_to_dynsym()
1545 gold_assert(this->link_section_
== NULL
1547 && !this->should_link_to_symtab_
);
1548 this->should_link_to_dynsym_
= true;
1551 // Return the info field.
1555 gold_assert(this->info_section_
== NULL
);
1559 // Set the info field to the output section index of a section.
1561 set_info_section(const Output_data
* od
)
1563 gold_assert(this->info_
== 0);
1564 this->info_section_
= od
;
1567 // Set the info field to a constant.
1569 set_info(unsigned int v
)
1571 gold_assert(this->info_section_
== NULL
);
1575 // Set the addralign field.
1577 set_addralign(uint64_t v
)
1578 { this->addralign_
= v
; }
1580 // Indicate that we need a symtab index.
1582 set_needs_symtab_index()
1583 { this->needs_symtab_index_
= true; }
1585 // Return whether we need a symtab index.
1587 needs_symtab_index() const
1588 { return this->needs_symtab_index_
; }
1590 // Get the symtab index.
1592 symtab_index() const
1594 gold_assert(this->symtab_index_
!= 0);
1595 return this->symtab_index_
;
1598 // Set the symtab index.
1600 set_symtab_index(unsigned int index
)
1602 gold_assert(index
!= 0);
1603 this->symtab_index_
= index
;
1606 // Indicate that we need a dynsym index.
1608 set_needs_dynsym_index()
1609 { this->needs_dynsym_index_
= true; }
1611 // Return whether we need a dynsym index.
1613 needs_dynsym_index() const
1614 { return this->needs_dynsym_index_
; }
1616 // Get the dynsym index.
1618 dynsym_index() const
1620 gold_assert(this->dynsym_index_
!= 0);
1621 return this->dynsym_index_
;
1624 // Set the dynsym index.
1626 set_dynsym_index(unsigned int index
)
1628 gold_assert(index
!= 0);
1629 this->dynsym_index_
= index
;
1632 // Return whether this section should be written after all the input
1633 // sections are complete.
1635 after_input_sections() const
1636 { return this->after_input_sections_
; }
1638 // Record that this section should be written after all the input
1639 // sections are complete.
1641 set_after_input_sections()
1642 { this->after_input_sections_
= true; }
1644 // Return whether this section requires postprocessing after all
1645 // relocations have been applied.
1647 requires_postprocessing() const
1648 { return this->requires_postprocessing_
; }
1650 // If a section requires postprocessing, return the buffer to use.
1652 postprocessing_buffer() const
1654 gold_assert(this->postprocessing_buffer_
!= NULL
);
1655 return this->postprocessing_buffer_
;
1658 // If a section requires postprocessing, create the buffer to use.
1660 create_postprocessing_buffer();
1662 // If a section requires postprocessing, this is the size of the
1663 // buffer to which relocations should be applied.
1665 postprocessing_buffer_size() const
1666 { return this->current_data_size_for_child(); }
1668 // Return whether the offset OFFSET in the input section SHNDX in
1669 // object OBJECT is being included in the link.
1671 is_input_address_mapped(const Relobj
* object
, unsigned int shndx
,
1672 off_t offset
) const;
1674 // Return the offset within the output section of OFFSET relative to
1675 // the start of input section SHNDX in object OBJECT.
1677 output_offset(const Relobj
* object
, unsigned int shndx
,
1678 section_offset_type offset
) const;
1680 // Return the output virtual address of OFFSET relative to the start
1681 // of input section SHNDX in object OBJECT.
1683 output_address(const Relobj
* object
, unsigned int shndx
,
1684 off_t offset
) const;
1686 // Write the section header into *OPHDR.
1687 template<int size
, bool big_endian
>
1689 write_header(const Layout
*, const Stringpool
*,
1690 elfcpp::Shdr_write
<size
, big_endian
>*) const;
1692 // Print merge statistics to stderr.
1694 print_merge_stats();
1697 // Return the section index in the output file.
1699 do_out_shndx() const
1701 gold_assert(this->out_shndx_
!= -1U);
1702 return this->out_shndx_
;
1705 // Set the output section index.
1707 do_set_out_shndx(unsigned int shndx
)
1709 gold_assert(this->out_shndx_
== -1U);
1710 this->out_shndx_
= shndx
;
1713 // Set the final data size of the Output_section. For a typical
1714 // Output_section, there is nothing to do, but if there are any
1715 // Output_section_data objects we need to set their final addresses
1718 set_final_data_size();
1720 // Write the data to the file. For a typical Output_section, this
1721 // does nothing: the data is written out by calling Object::Relocate
1722 // on each input object. But if there are any Output_section_data
1723 // objects we do need to write them out here.
1725 do_write(Output_file
*);
1727 // Return the address alignment--function required by parent class.
1729 do_addralign() const
1730 { return this->addralign_
; }
1732 // Return whether this is an Output_section.
1734 do_is_section() const
1737 // Return whether this is a section of the specified type.
1739 do_is_section_type(elfcpp::Elf_Word type
) const
1740 { return this->type_
== type
; }
1742 // Return whether the specified section flag is set.
1744 do_is_section_flag_set(elfcpp::Elf_Xword flag
) const
1745 { return (this->flags_
& flag
) != 0; }
1747 // Set the TLS offset. Called only for SHT_TLS sections.
1749 do_set_tls_offset(uint64_t tls_base
);
1751 // Return the TLS offset, relative to the base of the TLS segment.
1752 // Valid only for SHT_TLS sections.
1754 do_tls_offset() const
1755 { return this->tls_offset_
; }
1757 // Modify the section name. This is only permitted for an
1758 // unallocated section, and only before the size has been finalized.
1759 // Otherwise the name will not get into Layout::namepool_.
1761 set_name(const char* newname
)
1763 gold_assert((this->flags_
& elfcpp::SHF_ALLOC
) == 0);
1764 gold_assert(!this->is_data_size_valid());
1765 this->name_
= newname
;
1768 // This may be implemented by a child class.
1770 do_finalize_name(Layout
*)
1773 // Record that this section requires postprocessing after all
1774 // relocations have been applied. This is called by a child class.
1776 set_requires_postprocessing()
1778 this->requires_postprocessing_
= true;
1779 this->after_input_sections_
= true;
1782 // Write all the data of an Output_section into the postprocessing
1785 write_to_postprocessing_buffer();
1788 // In some cases we need to keep a list of the input sections
1789 // associated with this output section. We only need the list if we
1790 // might have to change the offsets of the input section within the
1791 // output section after we add the input section. The ordinary
1792 // input sections will be written out when we process the object
1793 // file, and as such we don't need to track them here. We do need
1794 // to track Output_section_data objects here. We store instances of
1795 // this structure in a std::vector, so it must be a POD. There can
1796 // be many instances of this structure, so we use a union to save
1802 : shndx_(0), p2align_(0)
1804 this->u1_
.data_size
= 0;
1805 this->u2_
.object
= NULL
;
1808 // For an ordinary input section.
1809 Input_section(Relobj
* object
, unsigned int shndx
, off_t data_size
,
1812 p2align_(ffsll(static_cast<long long>(addralign
)))
1814 gold_assert(shndx
!= OUTPUT_SECTION_CODE
1815 && shndx
!= MERGE_DATA_SECTION_CODE
1816 && shndx
!= MERGE_STRING_SECTION_CODE
);
1817 this->u1_
.data_size
= data_size
;
1818 this->u2_
.object
= object
;
1821 // For a non-merge output section.
1822 Input_section(Output_section_data
* posd
)
1823 : shndx_(OUTPUT_SECTION_CODE
),
1824 p2align_(ffsll(static_cast<long long>(posd
->addralign())))
1826 this->u1_
.data_size
= 0;
1827 this->u2_
.posd
= posd
;
1830 // For a merge section.
1831 Input_section(Output_section_data
* posd
, bool is_string
, uint64_t entsize
)
1833 ? MERGE_STRING_SECTION_CODE
1834 : MERGE_DATA_SECTION_CODE
),
1835 p2align_(ffsll(static_cast<long long>(posd
->addralign())))
1837 this->u1_
.entsize
= entsize
;
1838 this->u2_
.posd
= posd
;
1841 // The required alignment.
1845 return (this->p2align_
== 0
1847 : static_cast<uint64_t>(1) << (this->p2align_
- 1));
1850 // Return the required size.
1854 // Return whether this is a merge section which matches the
1857 is_merge_section(bool is_string
, uint64_t entsize
,
1858 uint64_t addralign
) const
1860 return (this->shndx_
== (is_string
1861 ? MERGE_STRING_SECTION_CODE
1862 : MERGE_DATA_SECTION_CODE
)
1863 && this->u1_
.entsize
== entsize
1864 && this->addralign() == addralign
);
1867 // Set the output section.
1869 set_output_section(Output_section
* os
)
1871 gold_assert(!this->is_input_section());
1872 this->u2_
.posd
->set_output_section(os
);
1875 // Set the address and file offset. This is called during
1876 // Layout::finalize. SECTION_FILE_OFFSET is the file offset of
1877 // the enclosing section.
1879 set_address_and_file_offset(uint64_t address
, off_t file_offset
,
1880 off_t section_file_offset
);
1882 // Finalize the data size.
1884 finalize_data_size();
1886 // Add an input section, for SHF_MERGE sections.
1888 add_input_section(Relobj
* object
, unsigned int shndx
)
1890 gold_assert(this->shndx_
== MERGE_DATA_SECTION_CODE
1891 || this->shndx_
== MERGE_STRING_SECTION_CODE
);
1892 return this->u2_
.posd
->add_input_section(object
, shndx
);
1895 // Given an input OBJECT, an input section index SHNDX within that
1896 // object, and an OFFSET relative to the start of that input
1897 // section, return whether or not the output offset is known. If
1898 // this function returns true, it sets *POUTPUT to the offset in
1899 // the output section, relative to the start of the input section
1900 // in the output section. *POUTPUT may be different from OFFSET
1901 // for a merged section.
1903 output_offset(const Relobj
* object
, unsigned int shndx
,
1904 section_offset_type offset
,
1905 section_offset_type
*poutput
) const;
1907 // Write out the data. This does nothing for an input section.
1909 write(Output_file
*);
1911 // Write the data to a buffer. This does nothing for an input
1914 write_to_buffer(unsigned char*);
1916 // Print statistics about merge sections to stderr.
1918 print_merge_stats(const char* section_name
)
1920 if (this->shndx_
== MERGE_DATA_SECTION_CODE
1921 || this->shndx_
== MERGE_STRING_SECTION_CODE
)
1922 this->u2_
.posd
->print_merge_stats(section_name
);
1926 // Code values which appear in shndx_. If the value is not one of
1927 // these codes, it is the input section index in the object file.
1930 // An Output_section_data.
1931 OUTPUT_SECTION_CODE
= -1U,
1932 // An Output_section_data for an SHF_MERGE section with
1933 // SHF_STRINGS not set.
1934 MERGE_DATA_SECTION_CODE
= -2U,
1935 // An Output_section_data for an SHF_MERGE section with
1937 MERGE_STRING_SECTION_CODE
= -3U
1940 // Whether this is an input section.
1942 is_input_section() const
1944 return (this->shndx_
!= OUTPUT_SECTION_CODE
1945 && this->shndx_
!= MERGE_DATA_SECTION_CODE
1946 && this->shndx_
!= MERGE_STRING_SECTION_CODE
);
1949 // For an ordinary input section, this is the section index in the
1950 // input file. For an Output_section_data, this is
1951 // OUTPUT_SECTION_CODE or MERGE_DATA_SECTION_CODE or
1952 // MERGE_STRING_SECTION_CODE.
1953 unsigned int shndx_
;
1954 // The required alignment, stored as a power of 2.
1955 unsigned int p2align_
;
1958 // For an ordinary input section, the section size.
1960 // For OUTPUT_SECTION_CODE, this is not used. For
1961 // MERGE_DATA_SECTION_CODE or MERGE_STRING_SECTION_CODE, the
1967 // For an ordinary input section, the object which holds the
1970 // For OUTPUT_SECTION_CODE or MERGE_DATA_SECTION_CODE or
1971 // MERGE_STRING_SECTION_CODE, the data.
1972 Output_section_data
* posd
;
1976 typedef std::vector
<Input_section
> Input_section_list
;
1978 // Fill data. This is used to fill in data between input sections.
1979 // When we have to keep track of the input sections, we can use an
1980 // Output_data_const, but we don't want to have to keep track of
1981 // input sections just to implement fills. For a fill we record the
1982 // offset, and the actual data to be written out.
1986 Fill(off_t section_offset
, off_t length
)
1987 : section_offset_(section_offset
), length_(length
)
1990 // Return section offset.
1992 section_offset() const
1993 { return this->section_offset_
; }
1995 // Return fill length.
1998 { return this->length_
; }
2001 // The offset within the output section.
2002 off_t section_offset_
;
2003 // The length of the space to fill.
2007 typedef std::vector
<Fill
> Fill_list
;
2009 // Add a new output section by Input_section.
2011 add_output_section_data(Input_section
*);
2013 // Add an SHF_MERGE input section. Returns true if the section was
2016 add_merge_input_section(Relobj
* object
, unsigned int shndx
, uint64_t flags
,
2017 uint64_t entsize
, uint64_t addralign
);
2019 // Add an output SHF_MERGE section POSD to this output section.
2020 // IS_STRING indicates whether it is a SHF_STRINGS section, and
2021 // ENTSIZE is the entity size. This returns the entry added to
2024 add_output_merge_section(Output_section_data
* posd
, bool is_string
,
2027 // Most of these fields are only valid after layout.
2029 // The name of the section. This will point into a Stringpool.
2031 // The section address is in the parent class.
2032 // The section alignment.
2033 uint64_t addralign_
;
2034 // The section entry size.
2036 // The file offset is in the parent class.
2037 // Set the section link field to the index of this section.
2038 const Output_data
* link_section_
;
2039 // If link_section_ is NULL, this is the link field.
2041 // Set the section info field to the index of this section.
2042 const Output_data
* info_section_
;
2043 // If info_section_ is NULL, this is the section info field.
2045 // The section type.
2046 const elfcpp::Elf_Word type_
;
2047 // The section flags.
2048 const elfcpp::Elf_Xword flags_
;
2049 // The section index.
2050 unsigned int out_shndx_
;
2051 // If there is a STT_SECTION for this output section in the normal
2052 // symbol table, this is the symbol index. This starts out as zero.
2053 // It is initialized in Layout::finalize() to be the index, or -1U
2054 // if there isn't one.
2055 unsigned int symtab_index_
;
2056 // If there is a STT_SECTION for this output section in the dynamic
2057 // symbol table, this is the symbol index. This starts out as zero.
2058 // It is initialized in Layout::finalize() to be the index, or -1U
2059 // if there isn't one.
2060 unsigned int dynsym_index_
;
2061 // The input sections. This will be empty in cases where we don't
2062 // need to keep track of them.
2063 Input_section_list input_sections_
;
2064 // The offset of the first entry in input_sections_.
2065 off_t first_input_offset_
;
2066 // The fill data. This is separate from input_sections_ because we
2067 // often will need fill sections without needing to keep track of
2070 // If the section requires postprocessing, this buffer holds the
2071 // section contents during relocation.
2072 unsigned char* postprocessing_buffer_
;
2073 // Whether this output section needs a STT_SECTION symbol in the
2074 // normal symbol table. This will be true if there is a relocation
2076 bool needs_symtab_index_
: 1;
2077 // Whether this output section needs a STT_SECTION symbol in the
2078 // dynamic symbol table. This will be true if there is a dynamic
2079 // relocation which needs it.
2080 bool needs_dynsym_index_
: 1;
2081 // Whether the link field of this output section should point to the
2082 // normal symbol table.
2083 bool should_link_to_symtab_
: 1;
2084 // Whether the link field of this output section should point to the
2085 // dynamic symbol table.
2086 bool should_link_to_dynsym_
: 1;
2087 // Whether this section should be written after all the input
2088 // sections are complete.
2089 bool after_input_sections_
: 1;
2090 // Whether this section requires post processing after all
2091 // relocations have been applied.
2092 bool requires_postprocessing_
: 1;
2093 // For SHT_TLS sections, the offset of this section relative to the base
2094 // of the TLS segment.
2095 uint64_t tls_offset_
;
2098 // An output segment. PT_LOAD segments are built from collections of
2099 // output sections. Other segments typically point within PT_LOAD
2100 // segments, and are built directly as needed.
2102 class Output_segment
2105 // Create an output segment, specifying the type and flags.
2106 Output_segment(elfcpp::Elf_Word
, elfcpp::Elf_Word
);
2108 // Return the virtual address.
2111 { return this->vaddr_
; }
2113 // Return the physical address.
2116 { return this->paddr_
; }
2118 // Return the segment type.
2121 { return this->type_
; }
2123 // Return the segment flags.
2126 { return this->flags_
; }
2128 // Return the memory size.
2131 { return this->memsz_
; }
2133 // Return the file size.
2136 { return this->filesz_
; }
2138 // Return the maximum alignment of the Output_data.
2142 // Add an Output_section to this segment.
2144 add_output_section(Output_section
* os
, elfcpp::Elf_Word seg_flags
)
2145 { this->add_output_section(os
, seg_flags
, false); }
2147 // Add an Output_section to the start of this segment.
2149 add_initial_output_section(Output_section
* os
, elfcpp::Elf_Word seg_flags
)
2150 { this->add_output_section(os
, seg_flags
, true); }
2152 // Add an Output_data (which is not an Output_section) to the start
2155 add_initial_output_data(Output_data
*);
2157 // Return the number of dynamic relocations applied to this segment.
2159 dynamic_reloc_count() const;
2161 // Set the address of the segment to ADDR and the offset to *POFF
2162 // (aligned if necessary), and set the addresses and offsets of all
2163 // contained output sections accordingly. Set the section indexes
2164 // of all contained output sections starting with *PSHNDX. Return
2165 // the address of the immediately following segment. Update *POFF
2166 // and *PSHNDX. This should only be called for a PT_LOAD segment.
2168 set_section_addresses(uint64_t addr
, off_t
* poff
, unsigned int* pshndx
);
2170 // Set the minimum alignment of this segment. This may be adjusted
2171 // upward based on the section alignments.
2173 set_minimum_addralign(uint64_t align
)
2175 gold_assert(!this->is_align_known_
);
2176 this->align_
= align
;
2179 // Set the offset of this segment based on the section. This should
2180 // only be called for a non-PT_LOAD segment.
2184 // Set the TLS offsets of the sections contained in the PT_TLS segment.
2188 // Return the number of output sections.
2190 output_section_count() const;
2192 // Write the segment header into *OPHDR.
2193 template<int size
, bool big_endian
>
2195 write_header(elfcpp::Phdr_write
<size
, big_endian
>*);
2197 // Write the section headers of associated sections into V.
2198 template<int size
, bool big_endian
>
2200 write_section_headers(const Layout
*, const Stringpool
*, unsigned char* v
,
2201 unsigned int* pshndx ACCEPT_SIZE_ENDIAN
) const;
2204 Output_segment(const Output_segment
&);
2205 Output_segment
& operator=(const Output_segment
&);
2207 typedef std::list
<Output_data
*> Output_data_list
;
2209 // Add an Output_section to this segment, specifying front or back.
2211 add_output_section(Output_section
*, elfcpp::Elf_Word seg_flags
,
2214 // Find the maximum alignment in an Output_data_list.
2216 maximum_alignment(const Output_data_list
*);
2218 // Set the section addresses in an Output_data_list.
2220 set_section_list_addresses(Output_data_list
*, uint64_t addr
, off_t
* poff
,
2221 unsigned int* pshndx
);
2223 // Return the number of Output_sections in an Output_data_list.
2225 output_section_count_list(const Output_data_list
*) const;
2227 // Return the number of dynamic relocs in an Output_data_list.
2229 dynamic_reloc_count_list(const Output_data_list
*) const;
2231 // Write the section headers in the list into V.
2232 template<int size
, bool big_endian
>
2234 write_section_headers_list(const Layout
*, const Stringpool
*,
2235 const Output_data_list
*, unsigned char* v
,
2236 unsigned int* pshdx ACCEPT_SIZE_ENDIAN
) const;
2238 // The list of output data with contents attached to this segment.
2239 Output_data_list output_data_
;
2240 // The list of output data without contents attached to this segment.
2241 Output_data_list output_bss_
;
2242 // The segment virtual address.
2244 // The segment physical address.
2246 // The size of the segment in memory.
2248 // The segment alignment. The is_align_known_ field indicates
2249 // whether this has been finalized. It can be set to a minimum
2250 // value before it is finalized.
2252 // The offset of the segment data within the file.
2254 // The size of the segment data in the file.
2256 // The segment type;
2257 elfcpp::Elf_Word type_
;
2258 // The segment flags.
2259 elfcpp::Elf_Word flags_
;
2260 // Whether we have finalized align_.
2261 bool is_align_known_
;
2264 // This class represents the output file.
2269 Output_file(const General_options
& options
, Target
*);
2271 // Get a pointer to the target.
2274 { return this->target_
; }
2276 // Open the output file. FILE_SIZE is the final size of the file.
2278 open(off_t file_size
);
2280 // Resize the output file.
2282 resize(off_t file_size
);
2284 // Close the output file (flushing all buffered data) and make sure
2285 // there are no errors.
2289 // We currently always use mmap which makes the view handling quite
2290 // simple. In the future we may support other approaches.
2292 // Write data to the output file.
2294 write(off_t offset
, const void* data
, size_t len
)
2295 { memcpy(this->base_
+ offset
, data
, len
); }
2297 // Get a buffer to use to write to the file, given the offset into
2298 // the file and the size.
2300 get_output_view(off_t start
, size_t size
)
2302 gold_assert(start
>= 0 && start
+ size
<= this->file_size_
);
2303 return this->base_
+ start
;
2306 // VIEW must have been returned by get_output_view. Write the
2307 // buffer to the file, passing in the offset and the size.
2309 write_output_view(off_t
, size_t, unsigned char*)
2312 // Get a read/write buffer. This is used when we want to write part
2313 // of the file, read it in, and write it again.
2315 get_input_output_view(off_t start
, size_t size
)
2316 { return this->get_output_view(start
, size
); }
2318 // Write a read/write buffer back to the file.
2320 write_input_output_view(off_t
, size_t, unsigned char*)
2323 // Get a read buffer. This is used when we just want to read part
2324 // of the file back it in.
2325 const unsigned char*
2326 get_input_view(off_t start
, size_t size
)
2327 { return this->get_output_view(start
, size
); }
2329 // Release a read bfufer.
2331 free_input_view(off_t
, size_t, const unsigned char*)
2335 // Map the file into memory and return a pointer to the map.
2339 // Unmap the file from memory (and flush to disk buffers).
2345 const General_options
& options_
;
2354 // Base of file mapped into memory.
2355 unsigned char* base_
;
2356 // True iff base_ points to a memory buffer rather than an output file.
2357 bool map_is_anonymous_
;
2360 } // End namespace gold.
2362 #endif // !defined(GOLD_OUTPUT_H)