1 // output.cc -- manage the output file for gold
21 // Output_data variables.
23 bool Output_data::sizes_are_fixed
;
25 // Output_data methods.
27 Output_data::~Output_data()
31 // Set the address and offset.
34 Output_data::set_address(uint64_t addr
, off_t off
)
36 this->address_
= addr
;
39 // Let the child class know.
40 this->do_set_address(addr
, off
);
43 // Return the default alignment for a size--32 or 64.
46 Output_data::default_alignment(int size
)
56 // Output_section_header methods. This currently assumes that the
57 // segment and section lists are complete at construction time.
59 Output_section_headers::Output_section_headers(
63 const Layout::Segment_list
* segment_list
,
64 const Layout::Section_list
* unattached_section_list
,
65 const Stringpool
* secnamepool
)
67 big_endian_(big_endian
),
69 segment_list_(segment_list
),
70 unattached_section_list_(unattached_section_list
),
71 secnamepool_(secnamepool
)
73 // Count all the sections. Start with 1 for the null section.
75 for (Layout::Segment_list::const_iterator p
= segment_list
->begin();
76 p
!= segment_list
->end();
78 if ((*p
)->type() == elfcpp::PT_LOAD
)
79 count
+= (*p
)->output_section_count();
80 count
+= unattached_section_list
->size();
84 shdr_size
= elfcpp::Elf_sizes
<32>::shdr_size
;
86 shdr_size
= elfcpp::Elf_sizes
<64>::shdr_size
;
90 this->set_data_size(count
* shdr_size
);
93 // Write out the section headers.
96 Output_section_headers::do_write(Output_file
* of
)
98 if (this->size_
== 32)
100 if (this->big_endian_
)
101 this->do_sized_write
<32, true>(of
);
103 this->do_sized_write
<32, false>(of
);
105 else if (this->size_
== 64)
107 if (this->big_endian_
)
108 this->do_sized_write
<64, true>(of
);
110 this->do_sized_write
<64, false>(of
);
116 template<int size
, bool big_endian
>
118 Output_section_headers::do_sized_write(Output_file
* of
)
120 off_t all_shdrs_size
= this->data_size();
121 unsigned char* view
= of
->get_output_view(this->offset(), all_shdrs_size
);
123 const int shdr_size
= elfcpp::Elf_sizes
<size
>::shdr_size
;
124 unsigned char* v
= view
;
127 typename
elfcpp::Shdr_write
<size
, big_endian
> oshdr(v
);
128 oshdr
.put_sh_name(0);
129 oshdr
.put_sh_type(elfcpp::SHT_NULL
);
130 oshdr
.put_sh_flags(0);
131 oshdr
.put_sh_addr(0);
132 oshdr
.put_sh_offset(0);
133 oshdr
.put_sh_size(0);
134 oshdr
.put_sh_link(0);
135 oshdr
.put_sh_info(0);
136 oshdr
.put_sh_addralign(0);
137 oshdr
.put_sh_entsize(0);
143 for (Layout::Segment_list::const_iterator p
= this->segment_list_
->begin();
144 p
!= this->segment_list_
->end();
146 v
= (*p
)->write_section_headers
SELECT_SIZE_ENDIAN_NAME(size
, big_endian
) (
147 this->layout_
, this->secnamepool_
, v
, &shndx
148 SELECT_SIZE_ENDIAN(size
, big_endian
));
149 for (Layout::Section_list::const_iterator p
=
150 this->unattached_section_list_
->begin();
151 p
!= this->unattached_section_list_
->end();
154 gold_assert(shndx
== (*p
)->out_shndx());
155 elfcpp::Shdr_write
<size
, big_endian
> oshdr(v
);
156 (*p
)->write_header(this->layout_
, this->secnamepool_
, &oshdr
);
161 of
->write_output_view(this->offset(), all_shdrs_size
, view
);
164 // Output_segment_header methods.
166 Output_segment_headers::Output_segment_headers(
169 const Layout::Segment_list
& segment_list
)
170 : size_(size
), big_endian_(big_endian
), segment_list_(segment_list
)
174 phdr_size
= elfcpp::Elf_sizes
<32>::phdr_size
;
176 phdr_size
= elfcpp::Elf_sizes
<64>::phdr_size
;
180 this->set_data_size(segment_list
.size() * phdr_size
);
184 Output_segment_headers::do_write(Output_file
* of
)
186 if (this->size_
== 32)
188 if (this->big_endian_
)
189 this->do_sized_write
<32, true>(of
);
191 this->do_sized_write
<32, false>(of
);
193 else if (this->size_
== 64)
195 if (this->big_endian_
)
196 this->do_sized_write
<64, true>(of
);
198 this->do_sized_write
<64, false>(of
);
204 template<int size
, bool big_endian
>
206 Output_segment_headers::do_sized_write(Output_file
* of
)
208 const int phdr_size
= elfcpp::Elf_sizes
<size
>::phdr_size
;
209 off_t all_phdrs_size
= this->segment_list_
.size() * phdr_size
;
210 unsigned char* view
= of
->get_output_view(this->offset(),
212 unsigned char* v
= view
;
213 for (Layout::Segment_list::const_iterator p
= this->segment_list_
.begin();
214 p
!= this->segment_list_
.end();
217 elfcpp::Phdr_write
<size
, big_endian
> ophdr(v
);
218 (*p
)->write_header(&ophdr
);
222 of
->write_output_view(this->offset(), all_phdrs_size
, view
);
225 // Output_file_header methods.
227 Output_file_header::Output_file_header(int size
,
229 const General_options
& options
,
230 const Target
* target
,
231 const Symbol_table
* symtab
,
232 const Output_segment_headers
* osh
)
234 big_endian_(big_endian
),
238 segment_header_(osh
),
239 section_header_(NULL
),
244 ehdr_size
= elfcpp::Elf_sizes
<32>::ehdr_size
;
246 ehdr_size
= elfcpp::Elf_sizes
<64>::ehdr_size
;
250 this->set_data_size(ehdr_size
);
253 // Set the section table information for a file header.
256 Output_file_header::set_section_info(const Output_section_headers
* shdrs
,
257 const Output_section
* shstrtab
)
259 this->section_header_
= shdrs
;
260 this->shstrtab_
= shstrtab
;
263 // Write out the file header.
266 Output_file_header::do_write(Output_file
* of
)
268 if (this->size_
== 32)
270 if (this->big_endian_
)
271 this->do_sized_write
<32, true>(of
);
273 this->do_sized_write
<32, false>(of
);
275 else if (this->size_
== 64)
277 if (this->big_endian_
)
278 this->do_sized_write
<64, true>(of
);
280 this->do_sized_write
<64, false>(of
);
286 // Write out the file header with appropriate size and endianess.
288 template<int size
, bool big_endian
>
290 Output_file_header::do_sized_write(Output_file
* of
)
292 gold_assert(this->offset() == 0);
294 int ehdr_size
= elfcpp::Elf_sizes
<size
>::ehdr_size
;
295 unsigned char* view
= of
->get_output_view(0, ehdr_size
);
296 elfcpp::Ehdr_write
<size
, big_endian
> oehdr(view
);
298 unsigned char e_ident
[elfcpp::EI_NIDENT
];
299 memset(e_ident
, 0, elfcpp::EI_NIDENT
);
300 e_ident
[elfcpp::EI_MAG0
] = elfcpp::ELFMAG0
;
301 e_ident
[elfcpp::EI_MAG1
] = elfcpp::ELFMAG1
;
302 e_ident
[elfcpp::EI_MAG2
] = elfcpp::ELFMAG2
;
303 e_ident
[elfcpp::EI_MAG3
] = elfcpp::ELFMAG3
;
305 e_ident
[elfcpp::EI_CLASS
] = elfcpp::ELFCLASS32
;
307 e_ident
[elfcpp::EI_CLASS
] = elfcpp::ELFCLASS64
;
310 e_ident
[elfcpp::EI_DATA
] = (big_endian
311 ? elfcpp::ELFDATA2MSB
312 : elfcpp::ELFDATA2LSB
);
313 e_ident
[elfcpp::EI_VERSION
] = elfcpp::EV_CURRENT
;
314 // FIXME: Some targets may need to set EI_OSABI and EI_ABIVERSION.
315 oehdr
.put_e_ident(e_ident
);
319 if (this->options_
.is_relocatable())
320 e_type
= elfcpp::ET_REL
;
322 e_type
= elfcpp::ET_EXEC
;
323 oehdr
.put_e_type(e_type
);
325 oehdr
.put_e_machine(this->target_
->machine_code());
326 oehdr
.put_e_version(elfcpp::EV_CURRENT
);
328 // FIXME: Need to support -e, and target specific entry symbol.
329 Symbol
* sym
= this->symtab_
->lookup("_start");
330 typename Sized_symbol
<size
>::Value_type v
;
335 Sized_symbol
<size
>* ssym
;
336 ssym
= this->symtab_
->get_sized_symbol
SELECT_SIZE_NAME(size
) (
337 sym
SELECT_SIZE(size
));
340 oehdr
.put_e_entry(v
);
342 oehdr
.put_e_phoff(this->segment_header_
->offset());
343 oehdr
.put_e_shoff(this->section_header_
->offset());
345 // FIXME: The target needs to set the flags.
346 oehdr
.put_e_flags(0);
348 oehdr
.put_e_ehsize(elfcpp::Elf_sizes
<size
>::ehdr_size
);
349 oehdr
.put_e_phentsize(elfcpp::Elf_sizes
<size
>::phdr_size
);
350 oehdr
.put_e_phnum(this->segment_header_
->data_size()
351 / elfcpp::Elf_sizes
<size
>::phdr_size
);
352 oehdr
.put_e_shentsize(elfcpp::Elf_sizes
<size
>::shdr_size
);
353 oehdr
.put_e_shnum(this->section_header_
->data_size()
354 / elfcpp::Elf_sizes
<size
>::shdr_size
);
355 oehdr
.put_e_shstrndx(this->shstrtab_
->out_shndx());
357 of
->write_output_view(0, ehdr_size
, view
);
360 // Output_data_const methods.
363 Output_data_const::do_write(Output_file
* of
)
365 of
->write(this->offset(), this->data_
.data(), this->data_
.size());
368 // Output_data_const_buffer methods.
371 Output_data_const_buffer::do_write(Output_file
* of
)
373 of
->write(this->offset(), this->p_
, this->data_size());
376 // Output_section_data methods.
378 // Record the output section, and set the entry size and such.
381 Output_section_data::set_output_section(Output_section
* os
)
383 gold_assert(this->output_section_
== NULL
);
384 this->output_section_
= os
;
385 this->do_adjust_output_section(os
);
388 // Return the section index of the output section.
391 Output_section_data::do_out_shndx() const
393 gold_assert(this->output_section_
!= NULL
);
394 return this->output_section_
->out_shndx();
397 // Output_data_strtab methods.
399 // Set the address. We don't actually care about the address, but we
400 // do set our final size.
403 Output_data_strtab::do_set_address(uint64_t, off_t
)
405 this->strtab_
->set_string_offsets();
406 this->set_data_size(this->strtab_
->get_strtab_size());
409 // Write out a string table.
412 Output_data_strtab::do_write(Output_file
* of
)
414 this->strtab_
->write(of
, this->offset());
417 // Output_reloc methods.
419 // Get the symbol index of a relocation.
421 template<bool dynamic
, int size
, bool big_endian
>
423 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::get_symbol_index()
427 switch (this->local_sym_index_
)
433 if (this->u1_
.gsym
== NULL
)
436 index
= this->u1_
.gsym
->dynsym_index();
438 index
= this->u1_
.gsym
->symtab_index();
443 index
= this->u1_
.os
->dynsym_index();
445 index
= this->u1_
.os
->symtab_index();
451 // FIXME: It seems that some targets may need to generate
452 // dynamic relocations against local symbols for some
453 // reasons. This will have to be addressed at some point.
457 index
= this->u1_
.relobj
->symtab_index(this->local_sym_index_
);
460 gold_assert(index
!= -1U);
464 // Write out the offset and info fields of a Rel or Rela relocation
467 template<bool dynamic
, int size
, bool big_endian
>
468 template<typename Write_rel
>
470 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::write_rel(
473 Address address
= this->address_
;
474 if (this->shndx_
!= INVALID_CODE
)
477 Output_section
* os
= this->u2_
.relobj
->output_section(this->shndx_
,
479 gold_assert(os
!= NULL
);
480 address
+= os
->address() + off
;
482 else if (this->u2_
.od
!= NULL
)
483 address
+= this->u2_
.od
->address();
484 wr
->put_r_offset(address
);
485 wr
->put_r_info(elfcpp::elf_r_info
<size
>(this->get_symbol_index(),
489 // Write out a Rel relocation.
491 template<bool dynamic
, int size
, bool big_endian
>
493 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::write(
494 unsigned char* pov
) const
496 elfcpp::Rel_write
<size
, big_endian
> orel(pov
);
497 this->write_rel(&orel
);
500 // Write out a Rela relocation.
502 template<bool dynamic
, int size
, bool big_endian
>
504 Output_reloc
<elfcpp::SHT_RELA
, dynamic
, size
, big_endian
>::write(
505 unsigned char* pov
) const
507 elfcpp::Rela_write
<size
, big_endian
> orel(pov
);
508 this->rel_
.write_rel(&orel
);
509 orel
.put_r_addend(this->addend_
);
512 // Output_data_reloc_base methods.
514 // Adjust the output section.
516 template<int sh_type
, bool dynamic
, int size
, bool big_endian
>
518 Output_data_reloc_base
<sh_type
, dynamic
, size
, big_endian
>
519 ::do_adjust_output_section(Output_section
* os
)
521 if (sh_type
== elfcpp::SHT_REL
)
522 os
->set_entsize(elfcpp::Elf_sizes
<size
>::rel_size
);
523 else if (sh_type
== elfcpp::SHT_RELA
)
524 os
->set_entsize(elfcpp::Elf_sizes
<size
>::rela_size
);
528 os
->set_should_link_to_dynsym();
530 os
->set_should_link_to_symtab();
533 // Write out relocation data.
535 template<int sh_type
, bool dynamic
, int size
, bool big_endian
>
537 Output_data_reloc_base
<sh_type
, dynamic
, size
, big_endian
>::do_write(
540 const off_t off
= this->offset();
541 const off_t oview_size
= this->data_size();
542 unsigned char* const oview
= of
->get_output_view(off
, oview_size
);
544 unsigned char* pov
= oview
;
545 for (typename
Relocs::const_iterator p
= this->relocs_
.begin();
546 p
!= this->relocs_
.end();
553 gold_assert(pov
- oview
== oview_size
);
555 of
->write_output_view(off
, oview_size
, oview
);
557 // We no longer need the relocation entries.
558 this->relocs_
.clear();
561 // Output_data_got::Got_entry methods.
563 // Write out the entry.
565 template<int size
, bool big_endian
>
567 Output_data_got
<size
, big_endian
>::Got_entry::write(
568 const General_options
* options
,
569 unsigned char* pov
) const
573 switch (this->local_sym_index_
)
577 Symbol
* gsym
= this->u_
.gsym
;
579 // If the symbol is resolved locally, we need to write out its
580 // value. Otherwise we just write zero. The target code is
581 // responsible for creating a relocation entry to fill in the
583 if (gsym
->final_value_is_known(options
))
585 Sized_symbol
<size
>* sgsym
;
586 // This cast is a bit ugly. We don't want to put a
587 // virtual method in Symbol, because we want Symbol to be
588 // as small as possible.
589 sgsym
= static_cast<Sized_symbol
<size
>*>(gsym
);
590 val
= sgsym
->value();
596 val
= this->u_
.constant
;
603 elfcpp::Swap
<size
, big_endian
>::writeval(pov
, val
);
606 // Output_data_got methods.
608 // Add an entry for a global symbol to the GOT. This returns true if
609 // this is a new GOT entry, false if the symbol already had a GOT
612 template<int size
, bool big_endian
>
614 Output_data_got
<size
, big_endian
>::add_global(Symbol
* gsym
)
616 if (gsym
->has_got_offset())
619 this->entries_
.push_back(Got_entry(gsym
));
620 this->set_got_size();
621 gsym
->set_got_offset(this->last_got_offset());
625 // Write out the GOT.
627 template<int size
, bool big_endian
>
629 Output_data_got
<size
, big_endian
>::do_write(Output_file
* of
)
631 const int add
= size
/ 8;
633 const off_t off
= this->offset();
634 const off_t oview_size
= this->data_size();
635 unsigned char* const oview
= of
->get_output_view(off
, oview_size
);
637 unsigned char* pov
= oview
;
638 for (typename
Got_entries::const_iterator p
= this->entries_
.begin();
639 p
!= this->entries_
.end();
642 p
->write(this->options_
, pov
);
646 gold_assert(pov
- oview
== oview_size
);
648 of
->write_output_view(off
, oview_size
, oview
);
650 // We no longer need the GOT entries.
651 this->entries_
.clear();
654 // Output_data_dynamic::Dynamic_entry methods.
656 // Write out the entry.
658 template<int size
, bool big_endian
>
660 Output_data_dynamic::Dynamic_entry::write(
662 const Stringpool
* pool
663 ACCEPT_SIZE_ENDIAN
) const
665 typename
elfcpp::Elf_types
<size
>::Elf_WXword val
;
666 switch (this->classification_
)
672 case DYNAMIC_SECTION_ADDRESS
:
673 val
= this->u_
.od
->address();
676 case DYNAMIC_SECTION_SIZE
:
677 val
= this->u_
.od
->data_size();
682 const Sized_symbol
<size
>* s
=
683 static_cast<const Sized_symbol
<size
>*>(this->u_
.sym
);
689 val
= pool
->get_offset(this->u_
.str
);
696 elfcpp::Dyn_write
<size
, big_endian
> dw(pov
);
697 dw
.put_d_tag(this->tag_
);
701 // Output_data_dynamic methods.
703 // Adjust the output section to set the entry size.
706 Output_data_dynamic::do_adjust_output_section(Output_section
* os
)
708 if (this->target_
->get_size() == 32)
709 os
->set_entsize(elfcpp::Elf_sizes
<32>::dyn_size
);
710 else if (this->target_
->get_size() == 64)
711 os
->set_entsize(elfcpp::Elf_sizes
<64>::dyn_size
);
716 // Set the final data size.
719 Output_data_dynamic::do_set_address(uint64_t, off_t
)
721 // Add the terminating entry.
722 this->add_constant(elfcpp::DT_NULL
, 0);
725 if (this->target_
->get_size() == 32)
726 dyn_size
= elfcpp::Elf_sizes
<32>::dyn_size
;
727 else if (this->target_
->get_size() == 64)
728 dyn_size
= elfcpp::Elf_sizes
<64>::dyn_size
;
731 this->set_data_size(this->entries_
.size() * dyn_size
);
734 // Write out the dynamic entries.
737 Output_data_dynamic::do_write(Output_file
* of
)
739 if (this->target_
->get_size() == 32)
741 if (this->target_
->is_big_endian())
742 this->sized_write
<32, true>(of
);
744 this->sized_write
<32, false>(of
);
746 else if (this->target_
->get_size() == 64)
748 if (this->target_
->is_big_endian())
749 this->sized_write
<64, true>(of
);
751 this->sized_write
<64, false>(of
);
757 template<int size
, bool big_endian
>
759 Output_data_dynamic::sized_write(Output_file
* of
)
761 const int dyn_size
= elfcpp::Elf_sizes
<size
>::dyn_size
;
763 const off_t offset
= this->offset();
764 const off_t oview_size
= this->data_size();
765 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
767 unsigned char* pov
= oview
;
768 for (typename
Dynamic_entries::const_iterator p
= this->entries_
.begin();
769 p
!= this->entries_
.end();
772 p
->write
SELECT_SIZE_ENDIAN_NAME(size
, big_endian
)(
773 pov
, this->pool_
SELECT_SIZE_ENDIAN(size
, big_endian
));
777 gold_assert(pov
- oview
== oview_size
);
779 of
->write_output_view(offset
, oview_size
, oview
);
781 // We no longer need the dynamic entries.
782 this->entries_
.clear();
785 // Output_section::Input_section methods.
787 // Return the data size. For an input section we store the size here.
788 // For an Output_section_data, we have to ask it for the size.
791 Output_section::Input_section::data_size() const
793 if (this->is_input_section())
794 return this->u1_
.data_size
;
796 return this->u2_
.posd
->data_size();
799 // Set the address and file offset.
802 Output_section::Input_section::set_address(uint64_t addr
, off_t off
,
805 if (this->is_input_section())
806 this->u2_
.object
->set_section_offset(this->shndx_
, off
- secoff
);
808 this->u2_
.posd
->set_address(addr
, off
);
811 // Try to turn an input address into an output address.
814 Output_section::Input_section::output_address(const Relobj
* object
,
817 uint64_t output_section_address
,
818 uint64_t *poutput
) const
820 if (!this->is_input_section())
821 return this->u2_
.posd
->output_address(object
, shndx
, offset
,
822 output_section_address
, poutput
);
825 if (this->u2_
.object
!= object
)
828 Output_section
* os
= object
->output_section(shndx
, &output_offset
);
829 gold_assert(os
!= NULL
);
830 *poutput
= output_section_address
+ output_offset
+ offset
;
835 // Write out the data. We don't have to do anything for an input
836 // section--they are handled via Object::relocate--but this is where
837 // we write out the data for an Output_section_data.
840 Output_section::Input_section::write(Output_file
* of
)
842 if (!this->is_input_section())
843 this->u2_
.posd
->write(of
);
846 // Output_section methods.
848 // Construct an Output_section. NAME will point into a Stringpool.
850 Output_section::Output_section(const char* name
, elfcpp::Elf_Word type
,
851 elfcpp::Elf_Xword flags
)
865 first_input_offset_(0),
867 needs_symtab_index_(false),
868 needs_dynsym_index_(false),
869 should_link_to_symtab_(false),
870 should_link_to_dynsym_(false)
874 Output_section::~Output_section()
878 // Set the entry size.
881 Output_section::set_entsize(uint64_t v
)
883 if (this->entsize_
== 0)
886 gold_assert(this->entsize_
== v
);
889 // Add the input section SHNDX, with header SHDR, named SECNAME, in
890 // OBJECT, to the Output_section. Return the offset of the input
891 // section within the output section. We don't always keep track of
892 // input sections for an Output_section. Instead, each Object keeps
893 // track of the Output_section for each of its input sections.
895 template<int size
, bool big_endian
>
897 Output_section::add_input_section(Relobj
* object
, unsigned int shndx
,
899 const elfcpp::Shdr
<size
, big_endian
>& shdr
)
901 elfcpp::Elf_Xword addralign
= shdr
.get_sh_addralign();
902 if ((addralign
& (addralign
- 1)) != 0)
904 fprintf(stderr
, _("%s: %s: invalid alignment %lu for section \"%s\"\n"),
905 program_name
, object
->name().c_str(),
906 static_cast<unsigned long>(addralign
), secname
);
910 if (addralign
> this->addralign_
)
911 this->addralign_
= addralign
;
913 // If this is a SHF_MERGE section, we pass all the input sections to
914 // a Output_data_merge.
915 if ((shdr
.get_sh_flags() & elfcpp::SHF_MERGE
) != 0)
917 if (this->add_merge_input_section(object
, shndx
, shdr
.get_sh_flags(),
918 shdr
.get_sh_entsize(),
921 // Tell the relocation routines that they need to call the
922 // output_address method to determine the final address.
927 off_t offset_in_section
= this->data_size();
928 off_t aligned_offset_in_section
= align_address(offset_in_section
,
931 if (aligned_offset_in_section
> offset_in_section
932 && (shdr
.get_sh_flags() & elfcpp::SHF_EXECINSTR
) != 0
933 && object
->target()->has_code_fill())
935 // We need to add some fill data. Using fill_list_ when
936 // possible is an optimization, since we will often have fill
937 // sections without input sections.
938 off_t fill_len
= aligned_offset_in_section
- offset_in_section
;
939 if (this->input_sections_
.empty())
940 this->fills_
.push_back(Fill(offset_in_section
, fill_len
));
943 // FIXME: When relaxing, the size needs to adjust to
944 // maintain a constant alignment.
945 std::string
fill_data(object
->target()->code_fill(fill_len
));
946 Output_data_const
* odc
= new Output_data_const(fill_data
, 1);
947 this->input_sections_
.push_back(Input_section(odc
));
951 this->set_data_size(aligned_offset_in_section
+ shdr
.get_sh_size());
953 // We need to keep track of this section if we are already keeping
954 // track of sections, or if we are relaxing. FIXME: Add test for
956 if (!this->input_sections_
.empty())
957 this->input_sections_
.push_back(Input_section(object
, shndx
,
961 return aligned_offset_in_section
;
964 // Add arbitrary data to an output section.
967 Output_section::add_output_section_data(Output_section_data
* posd
)
969 Input_section
inp(posd
);
970 this->add_output_section_data(&inp
);
973 // Add arbitrary data to an output section by Input_section.
976 Output_section::add_output_section_data(Input_section
* inp
)
978 if (this->input_sections_
.empty())
979 this->first_input_offset_
= this->data_size();
981 this->input_sections_
.push_back(*inp
);
983 uint64_t addralign
= inp
->addralign();
984 if (addralign
> this->addralign_
)
985 this->addralign_
= addralign
;
987 inp
->set_output_section(this);
990 // Add a merge section to an output section.
993 Output_section::add_output_merge_section(Output_section_data
* posd
,
994 bool is_string
, uint64_t entsize
)
996 Input_section
inp(posd
, is_string
, entsize
);
997 this->add_output_section_data(&inp
);
1000 // Add an input section to a SHF_MERGE section.
1003 Output_section::add_merge_input_section(Relobj
* object
, unsigned int shndx
,
1004 uint64_t flags
, uint64_t entsize
,
1007 // We only merge constants if the alignment is not more than the
1008 // entry size. This could be handled, but it's unusual.
1009 if (addralign
> entsize
)
1012 bool is_string
= (flags
& elfcpp::SHF_STRINGS
) != 0;
1013 Input_section_list::iterator p
;
1014 for (p
= this->input_sections_
.begin();
1015 p
!= this->input_sections_
.end();
1017 if (p
->is_merge_section(is_string
, entsize
))
1020 // We handle the actual constant merging in Output_merge_data or
1021 // Output_merge_string_data.
1022 if (p
!= this->input_sections_
.end())
1023 p
->add_input_section(object
, shndx
);
1026 Output_section_data
* posd
;
1028 posd
= new Output_merge_data(entsize
);
1029 else if (entsize
== 1)
1030 posd
= new Output_merge_string
<char>();
1031 else if (entsize
== 2)
1032 posd
= new Output_merge_string
<uint16_t>();
1033 else if (entsize
== 4)
1034 posd
= new Output_merge_string
<uint32_t>();
1038 this->add_output_merge_section(posd
, is_string
, entsize
);
1039 posd
->add_input_section(object
, shndx
);
1045 // Return the output virtual address of OFFSET relative to the start
1046 // of input section SHNDX in object OBJECT.
1049 Output_section::output_address(const Relobj
* object
, unsigned int shndx
,
1052 uint64_t addr
= this->address() + this->first_input_offset_
;
1053 for (Input_section_list::const_iterator p
= this->input_sections_
.begin();
1054 p
!= this->input_sections_
.end();
1057 addr
= align_address(addr
, p
->addralign());
1059 if (p
->output_address(object
, shndx
, offset
, addr
, &output
))
1061 addr
+= p
->data_size();
1064 // If we get here, it means that we don't know the mapping for this
1065 // input section. This might happen in principle if
1066 // add_input_section were called before add_output_section_data.
1067 // But it should never actually happen.
1072 // Set the address of an Output_section. This is where we handle
1073 // setting the addresses of any Output_section_data objects.
1076 Output_section::do_set_address(uint64_t address
, off_t startoff
)
1078 if (this->input_sections_
.empty())
1081 off_t off
= startoff
+ this->first_input_offset_
;
1082 for (Input_section_list::iterator p
= this->input_sections_
.begin();
1083 p
!= this->input_sections_
.end();
1086 off
= align_address(off
, p
->addralign());
1087 p
->set_address(address
+ (off
- startoff
), off
, startoff
);
1088 off
+= p
->data_size();
1091 this->set_data_size(off
- startoff
);
1094 // Write the section header to *OSHDR.
1096 template<int size
, bool big_endian
>
1098 Output_section::write_header(const Layout
* layout
,
1099 const Stringpool
* secnamepool
,
1100 elfcpp::Shdr_write
<size
, big_endian
>* oshdr
) const
1102 oshdr
->put_sh_name(secnamepool
->get_offset(this->name_
));
1103 oshdr
->put_sh_type(this->type_
);
1104 oshdr
->put_sh_flags(this->flags_
);
1105 oshdr
->put_sh_addr(this->address());
1106 oshdr
->put_sh_offset(this->offset());
1107 oshdr
->put_sh_size(this->data_size());
1108 if (this->link_section_
!= NULL
)
1109 oshdr
->put_sh_link(this->link_section_
->out_shndx());
1110 else if (this->should_link_to_symtab_
)
1111 oshdr
->put_sh_link(layout
->symtab_section()->out_shndx());
1112 else if (this->should_link_to_dynsym_
)
1113 oshdr
->put_sh_link(layout
->dynsym_section()->out_shndx());
1115 oshdr
->put_sh_link(this->link_
);
1116 if (this->info_section_
!= NULL
)
1117 oshdr
->put_sh_info(this->info_section_
->out_shndx());
1119 oshdr
->put_sh_info(this->info_
);
1120 oshdr
->put_sh_addralign(this->addralign_
);
1121 oshdr
->put_sh_entsize(this->entsize_
);
1124 // Write out the data. For input sections the data is written out by
1125 // Object::relocate, but we have to handle Output_section_data objects
1129 Output_section::do_write(Output_file
* of
)
1131 off_t output_section_file_offset
= this->offset();
1132 for (Fill_list::iterator p
= this->fills_
.begin();
1133 p
!= this->fills_
.end();
1136 std::string
fill_data(of
->target()->code_fill(p
->length()));
1137 of
->write(output_section_file_offset
+ p
->section_offset(),
1138 fill_data
.data(), fill_data
.size());
1141 for (Input_section_list::iterator p
= this->input_sections_
.begin();
1142 p
!= this->input_sections_
.end();
1147 // Output segment methods.
1149 Output_segment::Output_segment(elfcpp::Elf_Word type
, elfcpp::Elf_Word flags
)
1160 is_align_known_(false)
1164 // Add an Output_section to an Output_segment.
1167 Output_segment::add_output_section(Output_section
* os
,
1168 elfcpp::Elf_Word seg_flags
,
1171 gold_assert((os
->flags() & elfcpp::SHF_ALLOC
) != 0);
1172 gold_assert(!this->is_align_known_
);
1174 // Update the segment flags.
1175 this->flags_
|= seg_flags
;
1177 Output_segment::Output_data_list
* pdl
;
1178 if (os
->type() == elfcpp::SHT_NOBITS
)
1179 pdl
= &this->output_bss_
;
1181 pdl
= &this->output_data_
;
1183 // So that PT_NOTE segments will work correctly, we need to ensure
1184 // that all SHT_NOTE sections are adjacent. This will normally
1185 // happen automatically, because all the SHT_NOTE input sections
1186 // will wind up in the same output section. However, it is possible
1187 // for multiple SHT_NOTE input sections to have different section
1188 // flags, and thus be in different output sections, but for the
1189 // different section flags to map into the same segment flags and
1190 // thus the same output segment.
1192 // Note that while there may be many input sections in an output
1193 // section, there are normally only a few output sections in an
1194 // output segment. This loop is expected to be fast.
1196 if (os
->type() == elfcpp::SHT_NOTE
&& !pdl
->empty())
1198 Output_segment::Output_data_list::iterator p
= pdl
->end();
1202 if ((*p
)->is_section_type(elfcpp::SHT_NOTE
))
1204 // We don't worry about the FRONT parameter.
1210 while (p
!= pdl
->begin());
1213 // Similarly, so that PT_TLS segments will work, we need to group
1214 // SHF_TLS sections. An SHF_TLS/SHT_NOBITS section is a special
1215 // case: we group the SHF_TLS/SHT_NOBITS sections right after the
1216 // SHF_TLS/SHT_PROGBITS sections. This lets us set up PT_TLS
1218 if ((os
->flags() & elfcpp::SHF_TLS
) != 0 && !this->output_data_
.empty())
1220 pdl
= &this->output_data_
;
1221 bool nobits
= os
->type() == elfcpp::SHT_NOBITS
;
1222 bool sawtls
= false;
1223 Output_segment::Output_data_list::iterator p
= pdl
->end();
1228 if ((*p
)->is_section_flag_set(elfcpp::SHF_TLS
))
1231 // Put a NOBITS section after the first TLS section.
1232 // But a PROGBITS section after the first TLS/PROGBITS
1234 insert
= nobits
|| !(*p
)->is_section_type(elfcpp::SHT_NOBITS
);
1238 // If we've gone past the TLS sections, but we've seen a
1239 // TLS section, then we need to insert this section now.
1245 // We don't worry about the FRONT parameter.
1251 while (p
!= pdl
->begin());
1253 // There are no TLS sections yet; put this one at the requested
1254 // location in the section list.
1258 pdl
->push_front(os
);
1263 // Add an Output_data (which is not an Output_section) to the start of
1267 Output_segment::add_initial_output_data(Output_data
* od
)
1269 gold_assert(!this->is_align_known_
);
1270 this->output_data_
.push_front(od
);
1273 // Return the maximum alignment of the Output_data in Output_segment.
1274 // Once we compute this, we prohibit new sections from being added.
1277 Output_segment::addralign()
1279 if (!this->is_align_known_
)
1283 addralign
= Output_segment::maximum_alignment(&this->output_data_
);
1284 if (addralign
> this->align_
)
1285 this->align_
= addralign
;
1287 addralign
= Output_segment::maximum_alignment(&this->output_bss_
);
1288 if (addralign
> this->align_
)
1289 this->align_
= addralign
;
1291 this->is_align_known_
= true;
1294 return this->align_
;
1297 // Return the maximum alignment of a list of Output_data.
1300 Output_segment::maximum_alignment(const Output_data_list
* pdl
)
1303 for (Output_data_list::const_iterator p
= pdl
->begin();
1307 uint64_t addralign
= (*p
)->addralign();
1308 if (addralign
> ret
)
1314 // Set the section addresses for an Output_segment. ADDR is the
1315 // address and *POFF is the file offset. Set the section indexes
1316 // starting with *PSHNDX. Return the address of the immediately
1317 // following segment. Update *POFF and *PSHNDX.
1320 Output_segment::set_section_addresses(uint64_t addr
, off_t
* poff
,
1321 unsigned int* pshndx
)
1323 gold_assert(this->type_
== elfcpp::PT_LOAD
);
1325 this->vaddr_
= addr
;
1326 this->paddr_
= addr
;
1328 off_t orig_off
= *poff
;
1329 this->offset_
= orig_off
;
1331 *poff
= align_address(*poff
, this->addralign());
1333 addr
= this->set_section_list_addresses(&this->output_data_
, addr
, poff
,
1335 this->filesz_
= *poff
- orig_off
;
1339 uint64_t ret
= this->set_section_list_addresses(&this->output_bss_
, addr
,
1341 this->memsz_
= *poff
- orig_off
;
1343 // Ignore the file offset adjustments made by the BSS Output_data
1350 // Set the addresses and file offsets in a list of Output_data
1354 Output_segment::set_section_list_addresses(Output_data_list
* pdl
,
1355 uint64_t addr
, off_t
* poff
,
1356 unsigned int* pshndx
)
1358 off_t startoff
= *poff
;
1360 off_t off
= startoff
;
1361 for (Output_data_list::iterator p
= pdl
->begin();
1365 off
= align_address(off
, (*p
)->addralign());
1366 (*p
)->set_address(addr
+ (off
- startoff
), off
);
1368 // Unless this is a PT_TLS segment, we want to ignore the size
1369 // of a SHF_TLS/SHT_NOBITS section. Such a section does not
1370 // affect the size of a PT_LOAD segment.
1371 if (this->type_
== elfcpp::PT_TLS
1372 || !(*p
)->is_section_flag_set(elfcpp::SHF_TLS
)
1373 || !(*p
)->is_section_type(elfcpp::SHT_NOBITS
))
1374 off
+= (*p
)->data_size();
1376 if ((*p
)->is_section())
1378 (*p
)->set_out_shndx(*pshndx
);
1384 return addr
+ (off
- startoff
);
1387 // For a non-PT_LOAD segment, set the offset from the sections, if
1391 Output_segment::set_offset()
1393 gold_assert(this->type_
!= elfcpp::PT_LOAD
);
1395 if (this->output_data_
.empty() && this->output_bss_
.empty())
1406 const Output_data
* first
;
1407 if (this->output_data_
.empty())
1408 first
= this->output_bss_
.front();
1410 first
= this->output_data_
.front();
1411 this->vaddr_
= first
->address();
1412 this->paddr_
= this->vaddr_
;
1413 this->offset_
= first
->offset();
1415 if (this->output_data_
.empty())
1419 const Output_data
* last_data
= this->output_data_
.back();
1420 this->filesz_
= (last_data
->address()
1421 + last_data
->data_size()
1425 const Output_data
* last
;
1426 if (this->output_bss_
.empty())
1427 last
= this->output_data_
.back();
1429 last
= this->output_bss_
.back();
1430 this->memsz_
= (last
->address()
1435 // Return the number of Output_sections in an Output_segment.
1438 Output_segment::output_section_count() const
1440 return (this->output_section_count_list(&this->output_data_
)
1441 + this->output_section_count_list(&this->output_bss_
));
1444 // Return the number of Output_sections in an Output_data_list.
1447 Output_segment::output_section_count_list(const Output_data_list
* pdl
) const
1449 unsigned int count
= 0;
1450 for (Output_data_list::const_iterator p
= pdl
->begin();
1454 if ((*p
)->is_section())
1460 // Write the segment data into *OPHDR.
1462 template<int size
, bool big_endian
>
1464 Output_segment::write_header(elfcpp::Phdr_write
<size
, big_endian
>* ophdr
)
1466 ophdr
->put_p_type(this->type_
);
1467 ophdr
->put_p_offset(this->offset_
);
1468 ophdr
->put_p_vaddr(this->vaddr_
);
1469 ophdr
->put_p_paddr(this->paddr_
);
1470 ophdr
->put_p_filesz(this->filesz_
);
1471 ophdr
->put_p_memsz(this->memsz_
);
1472 ophdr
->put_p_flags(this->flags_
);
1473 ophdr
->put_p_align(this->addralign());
1476 // Write the section headers into V.
1478 template<int size
, bool big_endian
>
1480 Output_segment::write_section_headers(const Layout
* layout
,
1481 const Stringpool
* secnamepool
,
1483 unsigned int *pshndx
1484 ACCEPT_SIZE_ENDIAN
) const
1486 // Every section that is attached to a segment must be attached to a
1487 // PT_LOAD segment, so we only write out section headers for PT_LOAD
1489 if (this->type_
!= elfcpp::PT_LOAD
)
1492 v
= this->write_section_headers_list
1493 SELECT_SIZE_ENDIAN_NAME(size
, big_endian
) (
1494 layout
, secnamepool
, &this->output_data_
, v
, pshndx
1495 SELECT_SIZE_ENDIAN(size
, big_endian
));
1496 v
= this->write_section_headers_list
1497 SELECT_SIZE_ENDIAN_NAME(size
, big_endian
) (
1498 layout
, secnamepool
, &this->output_bss_
, v
, pshndx
1499 SELECT_SIZE_ENDIAN(size
, big_endian
));
1503 template<int size
, bool big_endian
>
1505 Output_segment::write_section_headers_list(const Layout
* layout
,
1506 const Stringpool
* secnamepool
,
1507 const Output_data_list
* pdl
,
1509 unsigned int* pshndx
1510 ACCEPT_SIZE_ENDIAN
) const
1512 const int shdr_size
= elfcpp::Elf_sizes
<size
>::shdr_size
;
1513 for (Output_data_list::const_iterator p
= pdl
->begin();
1517 if ((*p
)->is_section())
1519 const Output_section
* ps
= static_cast<const Output_section
*>(*p
);
1520 gold_assert(*pshndx
== ps
->out_shndx());
1521 elfcpp::Shdr_write
<size
, big_endian
> oshdr(v
);
1522 ps
->write_header(layout
, secnamepool
, &oshdr
);
1530 // Output_file methods.
1532 Output_file::Output_file(const General_options
& options
, Target
* target
)
1533 : options_(options
),
1535 name_(options
.output_file_name()),
1542 // Open the output file.
1545 Output_file::open(off_t file_size
)
1547 this->file_size_
= file_size
;
1549 int mode
= this->options_
.is_relocatable() ? 0666 : 0777;
1550 int o
= ::open(this->name_
, O_RDWR
| O_CREAT
| O_TRUNC
, mode
);
1553 fprintf(stderr
, _("%s: %s: open: %s\n"),
1554 program_name
, this->name_
, strerror(errno
));
1559 // Write out one byte to make the file the right size.
1560 if (::lseek(o
, file_size
- 1, SEEK_SET
) < 0)
1562 fprintf(stderr
, _("%s: %s: lseek: %s\n"),
1563 program_name
, this->name_
, strerror(errno
));
1567 if (::write(o
, &b
, 1) != 1)
1569 fprintf(stderr
, _("%s: %s: write: %s\n"),
1570 program_name
, this->name_
, strerror(errno
));
1574 // Map the file into memory.
1575 void* base
= ::mmap(NULL
, file_size
, PROT_READ
| PROT_WRITE
,
1577 if (base
== MAP_FAILED
)
1579 fprintf(stderr
, _("%s: %s: mmap: %s\n"),
1580 program_name
, this->name_
, strerror(errno
));
1583 this->base_
= static_cast<unsigned char*>(base
);
1586 // Close the output file.
1589 Output_file::close()
1591 if (::munmap(this->base_
, this->file_size_
) < 0)
1593 fprintf(stderr
, _("%s: %s: munmap: %s\n"),
1594 program_name
, this->name_
, strerror(errno
));
1599 if (::close(this->o_
) < 0)
1601 fprintf(stderr
, _("%s: %s: close: %s\n"),
1602 program_name
, this->name_
, strerror(errno
));
1608 // Instantiate the templates we need. We could use the configure
1609 // script to restrict this to only the ones for implemented targets.
1611 #ifdef HAVE_TARGET_32_LITTLE
1614 Output_section::add_input_section
<32, false>(
1617 const char* secname
,
1618 const elfcpp::Shdr
<32, false>& shdr
);
1621 #ifdef HAVE_TARGET_32_BIG
1624 Output_section::add_input_section
<32, true>(
1627 const char* secname
,
1628 const elfcpp::Shdr
<32, true>& shdr
);
1631 #ifdef HAVE_TARGET_64_LITTLE
1634 Output_section::add_input_section
<64, false>(
1637 const char* secname
,
1638 const elfcpp::Shdr
<64, false>& shdr
);
1641 #ifdef HAVE_TARGET_64_BIG
1644 Output_section::add_input_section
<64, true>(
1647 const char* secname
,
1648 const elfcpp::Shdr
<64, true>& shdr
);
1651 #ifdef HAVE_TARGET_32_LITTLE
1653 class Output_data_reloc
<elfcpp::SHT_REL
, false, 32, false>;
1656 #ifdef HAVE_TARGET_32_BIG
1658 class Output_data_reloc
<elfcpp::SHT_REL
, false, 32, true>;
1661 #ifdef HAVE_TARGET_64_LITTLE
1663 class Output_data_reloc
<elfcpp::SHT_REL
, false, 64, false>;
1666 #ifdef HAVE_TARGET_64_BIG
1668 class Output_data_reloc
<elfcpp::SHT_REL
, false, 64, true>;
1671 #ifdef HAVE_TARGET_32_LITTLE
1673 class Output_data_reloc
<elfcpp::SHT_REL
, true, 32, false>;
1676 #ifdef HAVE_TARGET_32_BIG
1678 class Output_data_reloc
<elfcpp::SHT_REL
, true, 32, true>;
1681 #ifdef HAVE_TARGET_64_LITTLE
1683 class Output_data_reloc
<elfcpp::SHT_REL
, true, 64, false>;
1686 #ifdef HAVE_TARGET_64_BIG
1688 class Output_data_reloc
<elfcpp::SHT_REL
, true, 64, true>;
1691 #ifdef HAVE_TARGET_32_LITTLE
1693 class Output_data_reloc
<elfcpp::SHT_RELA
, false, 32, false>;
1696 #ifdef HAVE_TARGET_32_BIG
1698 class Output_data_reloc
<elfcpp::SHT_RELA
, false, 32, true>;
1701 #ifdef HAVE_TARGET_64_LITTLE
1703 class Output_data_reloc
<elfcpp::SHT_RELA
, false, 64, false>;
1706 #ifdef HAVE_TARGET_64_BIG
1708 class Output_data_reloc
<elfcpp::SHT_RELA
, false, 64, true>;
1711 #ifdef HAVE_TARGET_32_LITTLE
1713 class Output_data_reloc
<elfcpp::SHT_RELA
, true, 32, false>;
1716 #ifdef HAVE_TARGET_32_BIG
1718 class Output_data_reloc
<elfcpp::SHT_RELA
, true, 32, true>;
1721 #ifdef HAVE_TARGET_64_LITTLE
1723 class Output_data_reloc
<elfcpp::SHT_RELA
, true, 64, false>;
1726 #ifdef HAVE_TARGET_64_BIG
1728 class Output_data_reloc
<elfcpp::SHT_RELA
, true, 64, true>;
1731 #ifdef HAVE_TARGET_32_LITTLE
1733 class Output_data_got
<32, false>;
1736 #ifdef HAVE_TARGET_32_BIG
1738 class Output_data_got
<32, true>;
1741 #ifdef HAVE_TARGET_64_LITTLE
1743 class Output_data_got
<64, false>;
1746 #ifdef HAVE_TARGET_64_BIG
1748 class Output_data_got
<64, true>;
1751 } // End namespace gold.