1 // output.cc -- manage the output file for gold
3 // Copyright 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
4 // Written by Ian Lance Taylor <iant@google.com>.
6 // This file is part of gold.
8 // This program is free software; you can redistribute it and/or modify
9 // it under the terms of the GNU General Public License as published by
10 // the Free Software Foundation; either version 3 of the License, or
11 // (at your option) any later version.
13 // This program is distributed in the hope that it will be useful,
14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 // GNU General Public License for more details.
18 // You should have received a copy of the GNU General Public License
19 // along with this program; if not, write to the Free Software
20 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
21 // MA 02110-1301, USA.
33 #include "libiberty.h"
35 #include "parameters.h"
40 #include "descriptors.h"
43 // Some BSD systems still use MAP_ANON instead of MAP_ANONYMOUS
45 # define MAP_ANONYMOUS MAP_ANON
48 #ifndef HAVE_POSIX_FALLOCATE
49 // A dummy, non general, version of posix_fallocate. Here we just set
50 // the file size and hope that there is enough disk space. FIXME: We
51 // could allocate disk space by walking block by block and writing a
52 // zero byte into each block.
54 posix_fallocate(int o
, off_t offset
, off_t len
)
56 return ftruncate(o
, offset
+ len
);
58 #endif // !defined(HAVE_POSIX_FALLOCATE)
63 // Output_data variables.
65 bool Output_data::allocated_sizes_are_fixed
;
67 // Output_data methods.
69 Output_data::~Output_data()
73 // Return the default alignment for the target size.
76 Output_data::default_alignment()
78 return Output_data::default_alignment_for_size(
79 parameters
->target().get_size());
82 // Return the default alignment for a size--32 or 64.
85 Output_data::default_alignment_for_size(int size
)
95 // Output_section_header methods. This currently assumes that the
96 // segment and section lists are complete at construction time.
98 Output_section_headers::Output_section_headers(
100 const Layout::Segment_list
* segment_list
,
101 const Layout::Section_list
* section_list
,
102 const Layout::Section_list
* unattached_section_list
,
103 const Stringpool
* secnamepool
,
104 const Output_section
* shstrtab_section
)
106 segment_list_(segment_list
),
107 section_list_(section_list
),
108 unattached_section_list_(unattached_section_list
),
109 secnamepool_(secnamepool
),
110 shstrtab_section_(shstrtab_section
)
114 // Compute the current data size.
117 Output_section_headers::do_size() const
119 // Count all the sections. Start with 1 for the null section.
121 if (!parameters
->options().relocatable())
123 for (Layout::Segment_list::const_iterator p
=
124 this->segment_list_
->begin();
125 p
!= this->segment_list_
->end();
127 if ((*p
)->type() == elfcpp::PT_LOAD
)
128 count
+= (*p
)->output_section_count();
132 for (Layout::Section_list::const_iterator p
=
133 this->section_list_
->begin();
134 p
!= this->section_list_
->end();
136 if (((*p
)->flags() & elfcpp::SHF_ALLOC
) != 0)
139 count
+= this->unattached_section_list_
->size();
141 const int size
= parameters
->target().get_size();
144 shdr_size
= elfcpp::Elf_sizes
<32>::shdr_size
;
146 shdr_size
= elfcpp::Elf_sizes
<64>::shdr_size
;
150 return count
* shdr_size
;
153 // Write out the section headers.
156 Output_section_headers::do_write(Output_file
* of
)
158 switch (parameters
->size_and_endianness())
160 #ifdef HAVE_TARGET_32_LITTLE
161 case Parameters::TARGET_32_LITTLE
:
162 this->do_sized_write
<32, false>(of
);
165 #ifdef HAVE_TARGET_32_BIG
166 case Parameters::TARGET_32_BIG
:
167 this->do_sized_write
<32, true>(of
);
170 #ifdef HAVE_TARGET_64_LITTLE
171 case Parameters::TARGET_64_LITTLE
:
172 this->do_sized_write
<64, false>(of
);
175 #ifdef HAVE_TARGET_64_BIG
176 case Parameters::TARGET_64_BIG
:
177 this->do_sized_write
<64, true>(of
);
185 template<int size
, bool big_endian
>
187 Output_section_headers::do_sized_write(Output_file
* of
)
189 off_t all_shdrs_size
= this->data_size();
190 unsigned char* view
= of
->get_output_view(this->offset(), all_shdrs_size
);
192 const int shdr_size
= elfcpp::Elf_sizes
<size
>::shdr_size
;
193 unsigned char* v
= view
;
196 typename
elfcpp::Shdr_write
<size
, big_endian
> oshdr(v
);
197 oshdr
.put_sh_name(0);
198 oshdr
.put_sh_type(elfcpp::SHT_NULL
);
199 oshdr
.put_sh_flags(0);
200 oshdr
.put_sh_addr(0);
201 oshdr
.put_sh_offset(0);
203 size_t section_count
= (this->data_size()
204 / elfcpp::Elf_sizes
<size
>::shdr_size
);
205 if (section_count
< elfcpp::SHN_LORESERVE
)
206 oshdr
.put_sh_size(0);
208 oshdr
.put_sh_size(section_count
);
210 unsigned int shstrndx
= this->shstrtab_section_
->out_shndx();
211 if (shstrndx
< elfcpp::SHN_LORESERVE
)
212 oshdr
.put_sh_link(0);
214 oshdr
.put_sh_link(shstrndx
);
216 oshdr
.put_sh_info(0);
217 oshdr
.put_sh_addralign(0);
218 oshdr
.put_sh_entsize(0);
223 unsigned int shndx
= 1;
224 if (!parameters
->options().relocatable())
226 for (Layout::Segment_list::const_iterator p
=
227 this->segment_list_
->begin();
228 p
!= this->segment_list_
->end();
230 v
= (*p
)->write_section_headers
<size
, big_endian
>(this->layout_
,
237 for (Layout::Section_list::const_iterator p
=
238 this->section_list_
->begin();
239 p
!= this->section_list_
->end();
242 // We do unallocated sections below, except that group
243 // sections have to come first.
244 if (((*p
)->flags() & elfcpp::SHF_ALLOC
) == 0
245 && (*p
)->type() != elfcpp::SHT_GROUP
)
247 gold_assert(shndx
== (*p
)->out_shndx());
248 elfcpp::Shdr_write
<size
, big_endian
> oshdr(v
);
249 (*p
)->write_header(this->layout_
, this->secnamepool_
, &oshdr
);
255 for (Layout::Section_list::const_iterator p
=
256 this->unattached_section_list_
->begin();
257 p
!= this->unattached_section_list_
->end();
260 // For a relocatable link, we did unallocated group sections
261 // above, since they have to come first.
262 if ((*p
)->type() == elfcpp::SHT_GROUP
263 && parameters
->options().relocatable())
265 gold_assert(shndx
== (*p
)->out_shndx());
266 elfcpp::Shdr_write
<size
, big_endian
> oshdr(v
);
267 (*p
)->write_header(this->layout_
, this->secnamepool_
, &oshdr
);
272 of
->write_output_view(this->offset(), all_shdrs_size
, view
);
275 // Output_segment_header methods.
277 Output_segment_headers::Output_segment_headers(
278 const Layout::Segment_list
& segment_list
)
279 : segment_list_(segment_list
)
284 Output_segment_headers::do_write(Output_file
* of
)
286 switch (parameters
->size_and_endianness())
288 #ifdef HAVE_TARGET_32_LITTLE
289 case Parameters::TARGET_32_LITTLE
:
290 this->do_sized_write
<32, false>(of
);
293 #ifdef HAVE_TARGET_32_BIG
294 case Parameters::TARGET_32_BIG
:
295 this->do_sized_write
<32, true>(of
);
298 #ifdef HAVE_TARGET_64_LITTLE
299 case Parameters::TARGET_64_LITTLE
:
300 this->do_sized_write
<64, false>(of
);
303 #ifdef HAVE_TARGET_64_BIG
304 case Parameters::TARGET_64_BIG
:
305 this->do_sized_write
<64, true>(of
);
313 template<int size
, bool big_endian
>
315 Output_segment_headers::do_sized_write(Output_file
* of
)
317 const int phdr_size
= elfcpp::Elf_sizes
<size
>::phdr_size
;
318 off_t all_phdrs_size
= this->segment_list_
.size() * phdr_size
;
319 gold_assert(all_phdrs_size
== this->data_size());
320 unsigned char* view
= of
->get_output_view(this->offset(),
322 unsigned char* v
= view
;
323 for (Layout::Segment_list::const_iterator p
= this->segment_list_
.begin();
324 p
!= this->segment_list_
.end();
327 elfcpp::Phdr_write
<size
, big_endian
> ophdr(v
);
328 (*p
)->write_header(&ophdr
);
332 gold_assert(v
- view
== all_phdrs_size
);
334 of
->write_output_view(this->offset(), all_phdrs_size
, view
);
338 Output_segment_headers::do_size() const
340 const int size
= parameters
->target().get_size();
343 phdr_size
= elfcpp::Elf_sizes
<32>::phdr_size
;
345 phdr_size
= elfcpp::Elf_sizes
<64>::phdr_size
;
349 return this->segment_list_
.size() * phdr_size
;
352 // Output_file_header methods.
354 Output_file_header::Output_file_header(const Target
* target
,
355 const Symbol_table
* symtab
,
356 const Output_segment_headers
* osh
,
360 segment_header_(osh
),
361 section_header_(NULL
),
365 this->set_data_size(this->do_size());
368 // Set the section table information for a file header.
371 Output_file_header::set_section_info(const Output_section_headers
* shdrs
,
372 const Output_section
* shstrtab
)
374 this->section_header_
= shdrs
;
375 this->shstrtab_
= shstrtab
;
378 // Write out the file header.
381 Output_file_header::do_write(Output_file
* of
)
383 gold_assert(this->offset() == 0);
385 switch (parameters
->size_and_endianness())
387 #ifdef HAVE_TARGET_32_LITTLE
388 case Parameters::TARGET_32_LITTLE
:
389 this->do_sized_write
<32, false>(of
);
392 #ifdef HAVE_TARGET_32_BIG
393 case Parameters::TARGET_32_BIG
:
394 this->do_sized_write
<32, true>(of
);
397 #ifdef HAVE_TARGET_64_LITTLE
398 case Parameters::TARGET_64_LITTLE
:
399 this->do_sized_write
<64, false>(of
);
402 #ifdef HAVE_TARGET_64_BIG
403 case Parameters::TARGET_64_BIG
:
404 this->do_sized_write
<64, true>(of
);
412 // Write out the file header with appropriate size and endianess.
414 template<int size
, bool big_endian
>
416 Output_file_header::do_sized_write(Output_file
* of
)
418 gold_assert(this->offset() == 0);
420 int ehdr_size
= elfcpp::Elf_sizes
<size
>::ehdr_size
;
421 unsigned char* view
= of
->get_output_view(0, ehdr_size
);
422 elfcpp::Ehdr_write
<size
, big_endian
> oehdr(view
);
424 unsigned char e_ident
[elfcpp::EI_NIDENT
];
425 memset(e_ident
, 0, elfcpp::EI_NIDENT
);
426 e_ident
[elfcpp::EI_MAG0
] = elfcpp::ELFMAG0
;
427 e_ident
[elfcpp::EI_MAG1
] = elfcpp::ELFMAG1
;
428 e_ident
[elfcpp::EI_MAG2
] = elfcpp::ELFMAG2
;
429 e_ident
[elfcpp::EI_MAG3
] = elfcpp::ELFMAG3
;
431 e_ident
[elfcpp::EI_CLASS
] = elfcpp::ELFCLASS32
;
433 e_ident
[elfcpp::EI_CLASS
] = elfcpp::ELFCLASS64
;
436 e_ident
[elfcpp::EI_DATA
] = (big_endian
437 ? elfcpp::ELFDATA2MSB
438 : elfcpp::ELFDATA2LSB
);
439 e_ident
[elfcpp::EI_VERSION
] = elfcpp::EV_CURRENT
;
440 oehdr
.put_e_ident(e_ident
);
443 if (parameters
->options().relocatable())
444 e_type
= elfcpp::ET_REL
;
445 else if (parameters
->options().shared())
446 e_type
= elfcpp::ET_DYN
;
448 e_type
= elfcpp::ET_EXEC
;
449 oehdr
.put_e_type(e_type
);
451 oehdr
.put_e_machine(this->target_
->machine_code());
452 oehdr
.put_e_version(elfcpp::EV_CURRENT
);
454 oehdr
.put_e_entry(this->entry
<size
>());
456 if (this->segment_header_
== NULL
)
457 oehdr
.put_e_phoff(0);
459 oehdr
.put_e_phoff(this->segment_header_
->offset());
461 oehdr
.put_e_shoff(this->section_header_
->offset());
463 // FIXME: The target needs to set the flags.
464 oehdr
.put_e_flags(0);
466 oehdr
.put_e_ehsize(elfcpp::Elf_sizes
<size
>::ehdr_size
);
468 if (this->segment_header_
== NULL
)
470 oehdr
.put_e_phentsize(0);
471 oehdr
.put_e_phnum(0);
475 oehdr
.put_e_phentsize(elfcpp::Elf_sizes
<size
>::phdr_size
);
476 oehdr
.put_e_phnum(this->segment_header_
->data_size()
477 / elfcpp::Elf_sizes
<size
>::phdr_size
);
480 oehdr
.put_e_shentsize(elfcpp::Elf_sizes
<size
>::shdr_size
);
481 size_t section_count
= (this->section_header_
->data_size()
482 / elfcpp::Elf_sizes
<size
>::shdr_size
);
484 if (section_count
< elfcpp::SHN_LORESERVE
)
485 oehdr
.put_e_shnum(this->section_header_
->data_size()
486 / elfcpp::Elf_sizes
<size
>::shdr_size
);
488 oehdr
.put_e_shnum(0);
490 unsigned int shstrndx
= this->shstrtab_
->out_shndx();
491 if (shstrndx
< elfcpp::SHN_LORESERVE
)
492 oehdr
.put_e_shstrndx(this->shstrtab_
->out_shndx());
494 oehdr
.put_e_shstrndx(elfcpp::SHN_XINDEX
);
496 // Let the target adjust the ELF header, e.g., to set EI_OSABI in
497 // the e_ident field.
498 parameters
->target().adjust_elf_header(view
, ehdr_size
);
500 of
->write_output_view(0, ehdr_size
, view
);
503 // Return the value to use for the entry address. THIS->ENTRY_ is the
504 // symbol specified on the command line, if any.
507 typename
elfcpp::Elf_types
<size
>::Elf_Addr
508 Output_file_header::entry()
510 const bool should_issue_warning
= (this->entry_
!= NULL
511 && !parameters
->options().relocatable()
512 && !parameters
->options().shared());
514 // FIXME: Need to support target specific entry symbol.
515 const char* entry
= this->entry_
;
519 Symbol
* sym
= this->symtab_
->lookup(entry
);
521 typename Sized_symbol
<size
>::Value_type v
;
524 Sized_symbol
<size
>* ssym
;
525 ssym
= this->symtab_
->get_sized_symbol
<size
>(sym
);
526 if (!ssym
->is_defined() && should_issue_warning
)
527 gold_warning("entry symbol '%s' exists but is not defined", entry
);
532 // We couldn't find the entry symbol. See if we can parse it as
533 // a number. This supports, e.g., -e 0x1000.
535 v
= strtoull(entry
, &endptr
, 0);
538 if (should_issue_warning
)
539 gold_warning("cannot find entry symbol '%s'", entry
);
547 // Compute the current data size.
550 Output_file_header::do_size() const
552 const int size
= parameters
->target().get_size();
554 return elfcpp::Elf_sizes
<32>::ehdr_size
;
556 return elfcpp::Elf_sizes
<64>::ehdr_size
;
561 // Output_data_const methods.
564 Output_data_const::do_write(Output_file
* of
)
566 of
->write(this->offset(), this->data_
.data(), this->data_
.size());
569 // Output_data_const_buffer methods.
572 Output_data_const_buffer::do_write(Output_file
* of
)
574 of
->write(this->offset(), this->p_
, this->data_size());
577 // Output_section_data methods.
579 // Record the output section, and set the entry size and such.
582 Output_section_data::set_output_section(Output_section
* os
)
584 gold_assert(this->output_section_
== NULL
);
585 this->output_section_
= os
;
586 this->do_adjust_output_section(os
);
589 // Return the section index of the output section.
592 Output_section_data::do_out_shndx() const
594 gold_assert(this->output_section_
!= NULL
);
595 return this->output_section_
->out_shndx();
598 // Set the alignment, which means we may need to update the alignment
599 // of the output section.
602 Output_section_data::set_addralign(uint64_t addralign
)
604 this->addralign_
= addralign
;
605 if (this->output_section_
!= NULL
606 && this->output_section_
->addralign() < addralign
)
607 this->output_section_
->set_addralign(addralign
);
610 // Output_data_strtab methods.
612 // Set the final data size.
615 Output_data_strtab::set_final_data_size()
617 this->strtab_
->set_string_offsets();
618 this->set_data_size(this->strtab_
->get_strtab_size());
621 // Write out a string table.
624 Output_data_strtab::do_write(Output_file
* of
)
626 this->strtab_
->write(of
, this->offset());
629 // Output_reloc methods.
631 // A reloc against a global symbol.
633 template<bool dynamic
, int size
, bool big_endian
>
634 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::Output_reloc(
640 : address_(address
), local_sym_index_(GSYM_CODE
), type_(type
),
641 is_relative_(is_relative
), is_section_symbol_(false), shndx_(INVALID_CODE
)
643 // this->type_ is a bitfield; make sure TYPE fits.
644 gold_assert(this->type_
== type
);
645 this->u1_
.gsym
= gsym
;
648 this->set_needs_dynsym_index();
651 template<bool dynamic
, int size
, bool big_endian
>
652 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::Output_reloc(
655 Sized_relobj
<size
, big_endian
>* relobj
,
659 : address_(address
), local_sym_index_(GSYM_CODE
), type_(type
),
660 is_relative_(is_relative
), is_section_symbol_(false), shndx_(shndx
)
662 gold_assert(shndx
!= INVALID_CODE
);
663 // this->type_ is a bitfield; make sure TYPE fits.
664 gold_assert(this->type_
== type
);
665 this->u1_
.gsym
= gsym
;
666 this->u2_
.relobj
= relobj
;
668 this->set_needs_dynsym_index();
671 // A reloc against a local symbol.
673 template<bool dynamic
, int size
, bool big_endian
>
674 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::Output_reloc(
675 Sized_relobj
<size
, big_endian
>* relobj
,
676 unsigned int local_sym_index
,
681 bool is_section_symbol
)
682 : address_(address
), local_sym_index_(local_sym_index
), type_(type
),
683 is_relative_(is_relative
), is_section_symbol_(is_section_symbol
),
686 gold_assert(local_sym_index
!= GSYM_CODE
687 && local_sym_index
!= INVALID_CODE
);
688 // this->type_ is a bitfield; make sure TYPE fits.
689 gold_assert(this->type_
== type
);
690 this->u1_
.relobj
= relobj
;
693 this->set_needs_dynsym_index();
696 template<bool dynamic
, int size
, bool big_endian
>
697 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::Output_reloc(
698 Sized_relobj
<size
, big_endian
>* relobj
,
699 unsigned int local_sym_index
,
704 bool is_section_symbol
)
705 : address_(address
), local_sym_index_(local_sym_index
), type_(type
),
706 is_relative_(is_relative
), is_section_symbol_(is_section_symbol
),
709 gold_assert(local_sym_index
!= GSYM_CODE
710 && local_sym_index
!= INVALID_CODE
);
711 gold_assert(shndx
!= INVALID_CODE
);
712 // this->type_ is a bitfield; make sure TYPE fits.
713 gold_assert(this->type_
== type
);
714 this->u1_
.relobj
= relobj
;
715 this->u2_
.relobj
= relobj
;
717 this->set_needs_dynsym_index();
720 // A reloc against the STT_SECTION symbol of an output section.
722 template<bool dynamic
, int size
, bool big_endian
>
723 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::Output_reloc(
728 : address_(address
), local_sym_index_(SECTION_CODE
), type_(type
),
729 is_relative_(false), is_section_symbol_(true), shndx_(INVALID_CODE
)
731 // this->type_ is a bitfield; make sure TYPE fits.
732 gold_assert(this->type_
== type
);
736 this->set_needs_dynsym_index();
738 os
->set_needs_symtab_index();
741 template<bool dynamic
, int size
, bool big_endian
>
742 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::Output_reloc(
745 Sized_relobj
<size
, big_endian
>* relobj
,
748 : address_(address
), local_sym_index_(SECTION_CODE
), type_(type
),
749 is_relative_(false), is_section_symbol_(true), shndx_(shndx
)
751 gold_assert(shndx
!= INVALID_CODE
);
752 // this->type_ is a bitfield; make sure TYPE fits.
753 gold_assert(this->type_
== type
);
755 this->u2_
.relobj
= relobj
;
757 this->set_needs_dynsym_index();
759 os
->set_needs_symtab_index();
762 // Record that we need a dynamic symbol index for this relocation.
764 template<bool dynamic
, int size
, bool big_endian
>
766 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::
767 set_needs_dynsym_index()
769 if (this->is_relative_
)
771 switch (this->local_sym_index_
)
777 this->u1_
.gsym
->set_needs_dynsym_entry();
781 this->u1_
.os
->set_needs_dynsym_index();
789 const unsigned int lsi
= this->local_sym_index_
;
790 if (!this->is_section_symbol_
)
791 this->u1_
.relobj
->set_needs_output_dynsym_entry(lsi
);
793 this->u1_
.relobj
->output_section(lsi
)->set_needs_dynsym_index();
799 // Get the symbol index of a relocation.
801 template<bool dynamic
, int size
, bool big_endian
>
803 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::get_symbol_index()
807 switch (this->local_sym_index_
)
813 if (this->u1_
.gsym
== NULL
)
816 index
= this->u1_
.gsym
->dynsym_index();
818 index
= this->u1_
.gsym
->symtab_index();
823 index
= this->u1_
.os
->dynsym_index();
825 index
= this->u1_
.os
->symtab_index();
829 // Relocations without symbols use a symbol index of 0.
835 const unsigned int lsi
= this->local_sym_index_
;
836 if (!this->is_section_symbol_
)
839 index
= this->u1_
.relobj
->dynsym_index(lsi
);
841 index
= this->u1_
.relobj
->symtab_index(lsi
);
845 Output_section
* os
= this->u1_
.relobj
->output_section(lsi
);
846 gold_assert(os
!= NULL
);
848 index
= os
->dynsym_index();
850 index
= os
->symtab_index();
855 gold_assert(index
!= -1U);
859 // For a local section symbol, get the address of the offset ADDEND
860 // within the input section.
862 template<bool dynamic
, int size
, bool big_endian
>
863 typename
elfcpp::Elf_types
<size
>::Elf_Addr
864 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::
865 local_section_offset(Addend addend
) const
867 gold_assert(this->local_sym_index_
!= GSYM_CODE
868 && this->local_sym_index_
!= SECTION_CODE
869 && this->local_sym_index_
!= INVALID_CODE
870 && this->is_section_symbol_
);
871 const unsigned int lsi
= this->local_sym_index_
;
872 Output_section
* os
= this->u1_
.relobj
->output_section(lsi
);
873 gold_assert(os
!= NULL
);
874 Address offset
= this->u1_
.relobj
->get_output_section_offset(lsi
);
875 if (offset
!= invalid_address
)
876 return offset
+ addend
;
877 // This is a merge section.
878 offset
= os
->output_address(this->u1_
.relobj
, lsi
, addend
);
879 gold_assert(offset
!= invalid_address
);
883 // Get the output address of a relocation.
885 template<bool dynamic
, int size
, bool big_endian
>
886 typename
elfcpp::Elf_types
<size
>::Elf_Addr
887 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::get_address() const
889 Address address
= this->address_
;
890 if (this->shndx_
!= INVALID_CODE
)
892 Output_section
* os
= this->u2_
.relobj
->output_section(this->shndx_
);
893 gold_assert(os
!= NULL
);
894 Address off
= this->u2_
.relobj
->get_output_section_offset(this->shndx_
);
895 if (off
!= invalid_address
)
896 address
+= os
->address() + off
;
899 address
= os
->output_address(this->u2_
.relobj
, this->shndx_
,
901 gold_assert(address
!= invalid_address
);
904 else if (this->u2_
.od
!= NULL
)
905 address
+= this->u2_
.od
->address();
909 // Write out the offset and info fields of a Rel or Rela relocation
912 template<bool dynamic
, int size
, bool big_endian
>
913 template<typename Write_rel
>
915 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::write_rel(
918 wr
->put_r_offset(this->get_address());
919 unsigned int sym_index
= this->is_relative_
? 0 : this->get_symbol_index();
920 wr
->put_r_info(elfcpp::elf_r_info
<size
>(sym_index
, this->type_
));
923 // Write out a Rel relocation.
925 template<bool dynamic
, int size
, bool big_endian
>
927 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::write(
928 unsigned char* pov
) const
930 elfcpp::Rel_write
<size
, big_endian
> orel(pov
);
931 this->write_rel(&orel
);
934 // Get the value of the symbol referred to by a Rel relocation.
936 template<bool dynamic
, int size
, bool big_endian
>
937 typename
elfcpp::Elf_types
<size
>::Elf_Addr
938 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::symbol_value(
941 if (this->local_sym_index_
== GSYM_CODE
)
943 const Sized_symbol
<size
>* sym
;
944 sym
= static_cast<const Sized_symbol
<size
>*>(this->u1_
.gsym
);
945 return sym
->value() + addend
;
947 gold_assert(this->local_sym_index_
!= SECTION_CODE
948 && this->local_sym_index_
!= INVALID_CODE
949 && !this->is_section_symbol_
);
950 const unsigned int lsi
= this->local_sym_index_
;
951 const Symbol_value
<size
>* symval
= this->u1_
.relobj
->local_symbol(lsi
);
952 return symval
->value(this->u1_
.relobj
, addend
);
955 // Reloc comparison. This function sorts the dynamic relocs for the
956 // benefit of the dynamic linker. First we sort all relative relocs
957 // to the front. Among relative relocs, we sort by output address.
958 // Among non-relative relocs, we sort by symbol index, then by output
961 template<bool dynamic
, int size
, bool big_endian
>
963 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::
964 compare(const Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>& r2
)
967 if (this->is_relative_
)
969 if (!r2
.is_relative_
)
971 // Otherwise sort by reloc address below.
973 else if (r2
.is_relative_
)
977 unsigned int sym1
= this->get_symbol_index();
978 unsigned int sym2
= r2
.get_symbol_index();
981 else if (sym1
> sym2
)
983 // Otherwise sort by reloc address.
986 section_offset_type addr1
= this->get_address();
987 section_offset_type addr2
= r2
.get_address();
990 else if (addr1
> addr2
)
993 // Final tie breaker, in order to generate the same output on any
995 unsigned int type1
= this->type_
;
996 unsigned int type2
= r2
.type_
;
999 else if (type1
> type2
)
1002 // These relocs appear to be exactly the same.
1006 // Write out a Rela relocation.
1008 template<bool dynamic
, int size
, bool big_endian
>
1010 Output_reloc
<elfcpp::SHT_RELA
, dynamic
, size
, big_endian
>::write(
1011 unsigned char* pov
) const
1013 elfcpp::Rela_write
<size
, big_endian
> orel(pov
);
1014 this->rel_
.write_rel(&orel
);
1015 Addend addend
= this->addend_
;
1016 if (this->rel_
.is_relative())
1017 addend
= this->rel_
.symbol_value(addend
);
1018 else if (this->rel_
.is_local_section_symbol())
1019 addend
= this->rel_
.local_section_offset(addend
);
1020 orel
.put_r_addend(addend
);
1023 // Output_data_reloc_base methods.
1025 // Adjust the output section.
1027 template<int sh_type
, bool dynamic
, int size
, bool big_endian
>
1029 Output_data_reloc_base
<sh_type
, dynamic
, size
, big_endian
>
1030 ::do_adjust_output_section(Output_section
* os
)
1032 if (sh_type
== elfcpp::SHT_REL
)
1033 os
->set_entsize(elfcpp::Elf_sizes
<size
>::rel_size
);
1034 else if (sh_type
== elfcpp::SHT_RELA
)
1035 os
->set_entsize(elfcpp::Elf_sizes
<size
>::rela_size
);
1039 os
->set_should_link_to_dynsym();
1041 os
->set_should_link_to_symtab();
1044 // Write out relocation data.
1046 template<int sh_type
, bool dynamic
, int size
, bool big_endian
>
1048 Output_data_reloc_base
<sh_type
, dynamic
, size
, big_endian
>::do_write(
1051 const off_t off
= this->offset();
1052 const off_t oview_size
= this->data_size();
1053 unsigned char* const oview
= of
->get_output_view(off
, oview_size
);
1055 if (this->sort_relocs_
)
1057 gold_assert(dynamic
);
1058 std::sort(this->relocs_
.begin(), this->relocs_
.end(),
1059 Sort_relocs_comparison());
1062 unsigned char* pov
= oview
;
1063 for (typename
Relocs::const_iterator p
= this->relocs_
.begin();
1064 p
!= this->relocs_
.end();
1071 gold_assert(pov
- oview
== oview_size
);
1073 of
->write_output_view(off
, oview_size
, oview
);
1075 // We no longer need the relocation entries.
1076 this->relocs_
.clear();
1079 // Class Output_relocatable_relocs.
1081 template<int sh_type
, int size
, bool big_endian
>
1083 Output_relocatable_relocs
<sh_type
, size
, big_endian
>::set_final_data_size()
1085 this->set_data_size(this->rr_
->output_reloc_count()
1086 * Reloc_types
<sh_type
, size
, big_endian
>::reloc_size
);
1089 // class Output_data_group.
1091 template<int size
, bool big_endian
>
1092 Output_data_group
<size
, big_endian
>::Output_data_group(
1093 Sized_relobj
<size
, big_endian
>* relobj
,
1094 section_size_type entry_count
,
1095 elfcpp::Elf_Word flags
,
1096 std::vector
<unsigned int>* input_shndxes
)
1097 : Output_section_data(entry_count
* 4, 4, false),
1101 this->input_shndxes_
.swap(*input_shndxes
);
1104 // Write out the section group, which means translating the section
1105 // indexes to apply to the output file.
1107 template<int size
, bool big_endian
>
1109 Output_data_group
<size
, big_endian
>::do_write(Output_file
* of
)
1111 const off_t off
= this->offset();
1112 const section_size_type oview_size
=
1113 convert_to_section_size_type(this->data_size());
1114 unsigned char* const oview
= of
->get_output_view(off
, oview_size
);
1116 elfcpp::Elf_Word
* contents
= reinterpret_cast<elfcpp::Elf_Word
*>(oview
);
1117 elfcpp::Swap
<32, big_endian
>::writeval(contents
, this->flags_
);
1120 for (std::vector
<unsigned int>::const_iterator p
=
1121 this->input_shndxes_
.begin();
1122 p
!= this->input_shndxes_
.end();
1125 Output_section
* os
= this->relobj_
->output_section(*p
);
1127 unsigned int output_shndx
;
1129 output_shndx
= os
->out_shndx();
1132 this->relobj_
->error(_("section group retained but "
1133 "group element discarded"));
1137 elfcpp::Swap
<32, big_endian
>::writeval(contents
, output_shndx
);
1140 size_t wrote
= reinterpret_cast<unsigned char*>(contents
) - oview
;
1141 gold_assert(wrote
== oview_size
);
1143 of
->write_output_view(off
, oview_size
, oview
);
1145 // We no longer need this information.
1146 this->input_shndxes_
.clear();
1149 // Output_data_got::Got_entry methods.
1151 // Write out the entry.
1153 template<int size
, bool big_endian
>
1155 Output_data_got
<size
, big_endian
>::Got_entry::write(unsigned char* pov
) const
1159 switch (this->local_sym_index_
)
1163 // If the symbol is resolved locally, we need to write out the
1164 // link-time value, which will be relocated dynamically by a
1165 // RELATIVE relocation.
1166 Symbol
* gsym
= this->u_
.gsym
;
1167 Sized_symbol
<size
>* sgsym
;
1168 // This cast is a bit ugly. We don't want to put a
1169 // virtual method in Symbol, because we want Symbol to be
1170 // as small as possible.
1171 sgsym
= static_cast<Sized_symbol
<size
>*>(gsym
);
1172 val
= sgsym
->value();
1177 val
= this->u_
.constant
;
1182 const unsigned int lsi
= this->local_sym_index_
;
1183 const Symbol_value
<size
>* symval
= this->u_
.object
->local_symbol(lsi
);
1184 val
= symval
->value(this->u_
.object
, 0);
1189 elfcpp::Swap
<size
, big_endian
>::writeval(pov
, val
);
1192 // Output_data_got methods.
1194 // Add an entry for a global symbol to the GOT. This returns true if
1195 // this is a new GOT entry, false if the symbol already had a GOT
1198 template<int size
, bool big_endian
>
1200 Output_data_got
<size
, big_endian
>::add_global(
1202 unsigned int got_type
)
1204 if (gsym
->has_got_offset(got_type
))
1207 this->entries_
.push_back(Got_entry(gsym
));
1208 this->set_got_size();
1209 gsym
->set_got_offset(got_type
, this->last_got_offset());
1213 // Add an entry for a global symbol to the GOT, and add a dynamic
1214 // relocation of type R_TYPE for the GOT entry.
1215 template<int size
, bool big_endian
>
1217 Output_data_got
<size
, big_endian
>::add_global_with_rel(
1219 unsigned int got_type
,
1221 unsigned int r_type
)
1223 if (gsym
->has_got_offset(got_type
))
1226 this->entries_
.push_back(Got_entry());
1227 this->set_got_size();
1228 unsigned int got_offset
= this->last_got_offset();
1229 gsym
->set_got_offset(got_type
, got_offset
);
1230 rel_dyn
->add_global(gsym
, r_type
, this, got_offset
);
1233 template<int size
, bool big_endian
>
1235 Output_data_got
<size
, big_endian
>::add_global_with_rela(
1237 unsigned int got_type
,
1239 unsigned int r_type
)
1241 if (gsym
->has_got_offset(got_type
))
1244 this->entries_
.push_back(Got_entry());
1245 this->set_got_size();
1246 unsigned int got_offset
= this->last_got_offset();
1247 gsym
->set_got_offset(got_type
, got_offset
);
1248 rela_dyn
->add_global(gsym
, r_type
, this, got_offset
, 0);
1251 // Add a pair of entries for a global symbol to the GOT, and add
1252 // dynamic relocations of type R_TYPE_1 and R_TYPE_2, respectively.
1253 // If R_TYPE_2 == 0, add the second entry with no relocation.
1254 template<int size
, bool big_endian
>
1256 Output_data_got
<size
, big_endian
>::add_global_pair_with_rel(
1258 unsigned int got_type
,
1260 unsigned int r_type_1
,
1261 unsigned int r_type_2
)
1263 if (gsym
->has_got_offset(got_type
))
1266 this->entries_
.push_back(Got_entry());
1267 unsigned int got_offset
= this->last_got_offset();
1268 gsym
->set_got_offset(got_type
, got_offset
);
1269 rel_dyn
->add_global(gsym
, r_type_1
, this, got_offset
);
1271 this->entries_
.push_back(Got_entry());
1274 got_offset
= this->last_got_offset();
1275 rel_dyn
->add_global(gsym
, r_type_2
, this, got_offset
);
1278 this->set_got_size();
1281 template<int size
, bool big_endian
>
1283 Output_data_got
<size
, big_endian
>::add_global_pair_with_rela(
1285 unsigned int got_type
,
1287 unsigned int r_type_1
,
1288 unsigned int r_type_2
)
1290 if (gsym
->has_got_offset(got_type
))
1293 this->entries_
.push_back(Got_entry());
1294 unsigned int got_offset
= this->last_got_offset();
1295 gsym
->set_got_offset(got_type
, got_offset
);
1296 rela_dyn
->add_global(gsym
, r_type_1
, this, got_offset
, 0);
1298 this->entries_
.push_back(Got_entry());
1301 got_offset
= this->last_got_offset();
1302 rela_dyn
->add_global(gsym
, r_type_2
, this, got_offset
, 0);
1305 this->set_got_size();
1308 // Add an entry for a local symbol to the GOT. This returns true if
1309 // this is a new GOT entry, false if the symbol already has a GOT
1312 template<int size
, bool big_endian
>
1314 Output_data_got
<size
, big_endian
>::add_local(
1315 Sized_relobj
<size
, big_endian
>* object
,
1316 unsigned int symndx
,
1317 unsigned int got_type
)
1319 if (object
->local_has_got_offset(symndx
, got_type
))
1322 this->entries_
.push_back(Got_entry(object
, symndx
));
1323 this->set_got_size();
1324 object
->set_local_got_offset(symndx
, got_type
, this->last_got_offset());
1328 // Add an entry for a local symbol to the GOT, and add a dynamic
1329 // relocation of type R_TYPE for the GOT entry.
1330 template<int size
, bool big_endian
>
1332 Output_data_got
<size
, big_endian
>::add_local_with_rel(
1333 Sized_relobj
<size
, big_endian
>* object
,
1334 unsigned int symndx
,
1335 unsigned int got_type
,
1337 unsigned int r_type
)
1339 if (object
->local_has_got_offset(symndx
, got_type
))
1342 this->entries_
.push_back(Got_entry());
1343 this->set_got_size();
1344 unsigned int got_offset
= this->last_got_offset();
1345 object
->set_local_got_offset(symndx
, got_type
, got_offset
);
1346 rel_dyn
->add_local(object
, symndx
, r_type
, this, got_offset
);
1349 template<int size
, bool big_endian
>
1351 Output_data_got
<size
, big_endian
>::add_local_with_rela(
1352 Sized_relobj
<size
, big_endian
>* object
,
1353 unsigned int symndx
,
1354 unsigned int got_type
,
1356 unsigned int r_type
)
1358 if (object
->local_has_got_offset(symndx
, got_type
))
1361 this->entries_
.push_back(Got_entry());
1362 this->set_got_size();
1363 unsigned int got_offset
= this->last_got_offset();
1364 object
->set_local_got_offset(symndx
, got_type
, got_offset
);
1365 rela_dyn
->add_local(object
, symndx
, r_type
, this, got_offset
, 0);
1368 // Add a pair of entries for a local symbol to the GOT, and add
1369 // dynamic relocations of type R_TYPE_1 and R_TYPE_2, respectively.
1370 // If R_TYPE_2 == 0, add the second entry with no relocation.
1371 template<int size
, bool big_endian
>
1373 Output_data_got
<size
, big_endian
>::add_local_pair_with_rel(
1374 Sized_relobj
<size
, big_endian
>* object
,
1375 unsigned int symndx
,
1377 unsigned int got_type
,
1379 unsigned int r_type_1
,
1380 unsigned int r_type_2
)
1382 if (object
->local_has_got_offset(symndx
, got_type
))
1385 this->entries_
.push_back(Got_entry());
1386 unsigned int got_offset
= this->last_got_offset();
1387 object
->set_local_got_offset(symndx
, got_type
, got_offset
);
1388 Output_section
* os
= object
->output_section(shndx
);
1389 rel_dyn
->add_output_section(os
, r_type_1
, this, got_offset
);
1391 this->entries_
.push_back(Got_entry(object
, symndx
));
1394 got_offset
= this->last_got_offset();
1395 rel_dyn
->add_output_section(os
, r_type_2
, this, got_offset
);
1398 this->set_got_size();
1401 template<int size
, bool big_endian
>
1403 Output_data_got
<size
, big_endian
>::add_local_pair_with_rela(
1404 Sized_relobj
<size
, big_endian
>* object
,
1405 unsigned int symndx
,
1407 unsigned int got_type
,
1409 unsigned int r_type_1
,
1410 unsigned int r_type_2
)
1412 if (object
->local_has_got_offset(symndx
, got_type
))
1415 this->entries_
.push_back(Got_entry());
1416 unsigned int got_offset
= this->last_got_offset();
1417 object
->set_local_got_offset(symndx
, got_type
, got_offset
);
1418 Output_section
* os
= object
->output_section(shndx
);
1419 rela_dyn
->add_output_section(os
, r_type_1
, this, got_offset
, 0);
1421 this->entries_
.push_back(Got_entry(object
, symndx
));
1424 got_offset
= this->last_got_offset();
1425 rela_dyn
->add_output_section(os
, r_type_2
, this, got_offset
, 0);
1428 this->set_got_size();
1431 // Write out the GOT.
1433 template<int size
, bool big_endian
>
1435 Output_data_got
<size
, big_endian
>::do_write(Output_file
* of
)
1437 const int add
= size
/ 8;
1439 const off_t off
= this->offset();
1440 const off_t oview_size
= this->data_size();
1441 unsigned char* const oview
= of
->get_output_view(off
, oview_size
);
1443 unsigned char* pov
= oview
;
1444 for (typename
Got_entries::const_iterator p
= this->entries_
.begin();
1445 p
!= this->entries_
.end();
1452 gold_assert(pov
- oview
== oview_size
);
1454 of
->write_output_view(off
, oview_size
, oview
);
1456 // We no longer need the GOT entries.
1457 this->entries_
.clear();
1460 // Output_data_dynamic::Dynamic_entry methods.
1462 // Write out the entry.
1464 template<int size
, bool big_endian
>
1466 Output_data_dynamic::Dynamic_entry::write(
1468 const Stringpool
* pool
) const
1470 typename
elfcpp::Elf_types
<size
>::Elf_WXword val
;
1471 switch (this->offset_
)
1473 case DYNAMIC_NUMBER
:
1477 case DYNAMIC_SECTION_SIZE
:
1478 val
= this->u_
.od
->data_size();
1481 case DYNAMIC_SYMBOL
:
1483 const Sized_symbol
<size
>* s
=
1484 static_cast<const Sized_symbol
<size
>*>(this->u_
.sym
);
1489 case DYNAMIC_STRING
:
1490 val
= pool
->get_offset(this->u_
.str
);
1494 val
= this->u_
.od
->address() + this->offset_
;
1498 elfcpp::Dyn_write
<size
, big_endian
> dw(pov
);
1499 dw
.put_d_tag(this->tag_
);
1503 // Output_data_dynamic methods.
1505 // Adjust the output section to set the entry size.
1508 Output_data_dynamic::do_adjust_output_section(Output_section
* os
)
1510 if (parameters
->target().get_size() == 32)
1511 os
->set_entsize(elfcpp::Elf_sizes
<32>::dyn_size
);
1512 else if (parameters
->target().get_size() == 64)
1513 os
->set_entsize(elfcpp::Elf_sizes
<64>::dyn_size
);
1518 // Set the final data size.
1521 Output_data_dynamic::set_final_data_size()
1523 // Add the terminating entry if it hasn't been added.
1524 // Because of relaxation, we can run this multiple times.
1525 if (this->entries_
.empty()
1526 || this->entries_
.rbegin()->tag() != elfcpp::DT_NULL
)
1527 this->add_constant(elfcpp::DT_NULL
, 0);
1530 if (parameters
->target().get_size() == 32)
1531 dyn_size
= elfcpp::Elf_sizes
<32>::dyn_size
;
1532 else if (parameters
->target().get_size() == 64)
1533 dyn_size
= elfcpp::Elf_sizes
<64>::dyn_size
;
1536 this->set_data_size(this->entries_
.size() * dyn_size
);
1539 // Write out the dynamic entries.
1542 Output_data_dynamic::do_write(Output_file
* of
)
1544 switch (parameters
->size_and_endianness())
1546 #ifdef HAVE_TARGET_32_LITTLE
1547 case Parameters::TARGET_32_LITTLE
:
1548 this->sized_write
<32, false>(of
);
1551 #ifdef HAVE_TARGET_32_BIG
1552 case Parameters::TARGET_32_BIG
:
1553 this->sized_write
<32, true>(of
);
1556 #ifdef HAVE_TARGET_64_LITTLE
1557 case Parameters::TARGET_64_LITTLE
:
1558 this->sized_write
<64, false>(of
);
1561 #ifdef HAVE_TARGET_64_BIG
1562 case Parameters::TARGET_64_BIG
:
1563 this->sized_write
<64, true>(of
);
1571 template<int size
, bool big_endian
>
1573 Output_data_dynamic::sized_write(Output_file
* of
)
1575 const int dyn_size
= elfcpp::Elf_sizes
<size
>::dyn_size
;
1577 const off_t offset
= this->offset();
1578 const off_t oview_size
= this->data_size();
1579 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
1581 unsigned char* pov
= oview
;
1582 for (typename
Dynamic_entries::const_iterator p
= this->entries_
.begin();
1583 p
!= this->entries_
.end();
1586 p
->write
<size
, big_endian
>(pov
, this->pool_
);
1590 gold_assert(pov
- oview
== oview_size
);
1592 of
->write_output_view(offset
, oview_size
, oview
);
1594 // We no longer need the dynamic entries.
1595 this->entries_
.clear();
1598 // Class Output_symtab_xindex.
1601 Output_symtab_xindex::do_write(Output_file
* of
)
1603 const off_t offset
= this->offset();
1604 const off_t oview_size
= this->data_size();
1605 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
1607 memset(oview
, 0, oview_size
);
1609 if (parameters
->target().is_big_endian())
1610 this->endian_do_write
<true>(oview
);
1612 this->endian_do_write
<false>(oview
);
1614 of
->write_output_view(offset
, oview_size
, oview
);
1616 // We no longer need the data.
1617 this->entries_
.clear();
1620 template<bool big_endian
>
1622 Output_symtab_xindex::endian_do_write(unsigned char* const oview
)
1624 for (Xindex_entries::const_iterator p
= this->entries_
.begin();
1625 p
!= this->entries_
.end();
1628 unsigned int symndx
= p
->first
;
1629 gold_assert(symndx
* 4 < this->data_size());
1630 elfcpp::Swap
<32, big_endian
>::writeval(oview
+ symndx
* 4, p
->second
);
1634 // Output_section::Input_section methods.
1636 // Return the data size. For an input section we store the size here.
1637 // For an Output_section_data, we have to ask it for the size.
1640 Output_section::Input_section::data_size() const
1642 if (this->is_input_section())
1643 return this->u1_
.data_size
;
1645 return this->u2_
.posd
->data_size();
1648 // Set the address and file offset.
1651 Output_section::Input_section::set_address_and_file_offset(
1654 off_t section_file_offset
)
1656 if (this->is_input_section())
1657 this->u2_
.object
->set_section_offset(this->shndx_
,
1658 file_offset
- section_file_offset
);
1660 this->u2_
.posd
->set_address_and_file_offset(address
, file_offset
);
1663 // Reset the address and file offset.
1666 Output_section::Input_section::reset_address_and_file_offset()
1668 if (!this->is_input_section())
1669 this->u2_
.posd
->reset_address_and_file_offset();
1672 // Finalize the data size.
1675 Output_section::Input_section::finalize_data_size()
1677 if (!this->is_input_section())
1678 this->u2_
.posd
->finalize_data_size();
1681 // Try to turn an input offset into an output offset. We want to
1682 // return the output offset relative to the start of this
1683 // Input_section in the output section.
1686 Output_section::Input_section::output_offset(
1687 const Relobj
* object
,
1689 section_offset_type offset
,
1690 section_offset_type
*poutput
) const
1692 if (!this->is_input_section())
1693 return this->u2_
.posd
->output_offset(object
, shndx
, offset
, poutput
);
1696 if (this->shndx_
!= shndx
|| this->u2_
.object
!= object
)
1703 // Return whether this is the merge section for the input section
1707 Output_section::Input_section::is_merge_section_for(const Relobj
* object
,
1708 unsigned int shndx
) const
1710 if (this->is_input_section())
1712 return this->u2_
.posd
->is_merge_section_for(object
, shndx
);
1715 // Write out the data. We don't have to do anything for an input
1716 // section--they are handled via Object::relocate--but this is where
1717 // we write out the data for an Output_section_data.
1720 Output_section::Input_section::write(Output_file
* of
)
1722 if (!this->is_input_section())
1723 this->u2_
.posd
->write(of
);
1726 // Write the data to a buffer. As for write(), we don't have to do
1727 // anything for an input section.
1730 Output_section::Input_section::write_to_buffer(unsigned char* buffer
)
1732 if (!this->is_input_section())
1733 this->u2_
.posd
->write_to_buffer(buffer
);
1736 // Print to a map file.
1739 Output_section::Input_section::print_to_mapfile(Mapfile
* mapfile
) const
1741 switch (this->shndx_
)
1743 case OUTPUT_SECTION_CODE
:
1744 case MERGE_DATA_SECTION_CODE
:
1745 case MERGE_STRING_SECTION_CODE
:
1746 this->u2_
.posd
->print_to_mapfile(mapfile
);
1749 case RELAXED_INPUT_SECTION_CODE
:
1751 Output_relaxed_input_section
* relaxed_section
=
1752 this->relaxed_input_section();
1753 mapfile
->print_input_section(relaxed_section
->relobj(),
1754 relaxed_section
->shndx());
1758 mapfile
->print_input_section(this->u2_
.object
, this->shndx_
);
1763 // Output_section methods.
1765 // Construct an Output_section. NAME will point into a Stringpool.
1767 Output_section::Output_section(const char* name
, elfcpp::Elf_Word type
,
1768 elfcpp::Elf_Xword flags
)
1773 link_section_(NULL
),
1775 info_section_(NULL
),
1784 first_input_offset_(0),
1786 postprocessing_buffer_(NULL
),
1787 needs_symtab_index_(false),
1788 needs_dynsym_index_(false),
1789 should_link_to_symtab_(false),
1790 should_link_to_dynsym_(false),
1791 after_input_sections_(false),
1792 requires_postprocessing_(false),
1793 found_in_sections_clause_(false),
1794 has_load_address_(false),
1795 info_uses_section_index_(false),
1796 may_sort_attached_input_sections_(false),
1797 must_sort_attached_input_sections_(false),
1798 attached_input_sections_are_sorted_(false),
1800 is_relro_local_(false),
1801 is_small_section_(false),
1802 is_large_section_(false),
1806 // An unallocated section has no address. Forcing this means that
1807 // we don't need special treatment for symbols defined in debug
1809 if ((flags
& elfcpp::SHF_ALLOC
) == 0)
1810 this->set_address(0);
1813 Output_section::~Output_section()
1815 delete this->checkpoint_
;
1818 // Set the entry size.
1821 Output_section::set_entsize(uint64_t v
)
1823 if (this->entsize_
== 0)
1826 gold_assert(this->entsize_
== v
);
1829 // Add the input section SHNDX, with header SHDR, named SECNAME, in
1830 // OBJECT, to the Output_section. RELOC_SHNDX is the index of a
1831 // relocation section which applies to this section, or 0 if none, or
1832 // -1U if more than one. Return the offset of the input section
1833 // within the output section. Return -1 if the input section will
1834 // receive special handling. In the normal case we don't always keep
1835 // track of input sections for an Output_section. Instead, each
1836 // Object keeps track of the Output_section for each of its input
1837 // sections. However, if HAVE_SECTIONS_SCRIPT is true, we do keep
1838 // track of input sections here; this is used when SECTIONS appears in
1841 template<int size
, bool big_endian
>
1843 Output_section::add_input_section(Sized_relobj
<size
, big_endian
>* object
,
1845 const char* secname
,
1846 const elfcpp::Shdr
<size
, big_endian
>& shdr
,
1847 unsigned int reloc_shndx
,
1848 bool have_sections_script
)
1850 elfcpp::Elf_Xword addralign
= shdr
.get_sh_addralign();
1851 if ((addralign
& (addralign
- 1)) != 0)
1853 object
->error(_("invalid alignment %lu for section \"%s\""),
1854 static_cast<unsigned long>(addralign
), secname
);
1858 if (addralign
> this->addralign_
)
1859 this->addralign_
= addralign
;
1861 typename
elfcpp::Elf_types
<size
>::Elf_WXword sh_flags
= shdr
.get_sh_flags();
1862 this->update_flags_for_input_section(sh_flags
);
1864 uint64_t entsize
= shdr
.get_sh_entsize();
1866 // .debug_str is a mergeable string section, but is not always so
1867 // marked by compilers. Mark manually here so we can optimize.
1868 if (strcmp(secname
, ".debug_str") == 0)
1870 sh_flags
|= (elfcpp::SHF_MERGE
| elfcpp::SHF_STRINGS
);
1874 // If this is a SHF_MERGE section, we pass all the input sections to
1875 // a Output_data_merge. We don't try to handle relocations for such
1876 // a section. We don't try to handle empty merge sections--they
1877 // mess up the mappings, and are useless anyhow.
1878 if ((sh_flags
& elfcpp::SHF_MERGE
) != 0
1880 && shdr
.get_sh_size() > 0)
1882 if (this->add_merge_input_section(object
, shndx
, sh_flags
,
1883 entsize
, addralign
))
1885 // Tell the relocation routines that they need to call the
1886 // output_offset method to determine the final address.
1891 off_t offset_in_section
= this->current_data_size_for_child();
1892 off_t aligned_offset_in_section
= align_address(offset_in_section
,
1895 if (aligned_offset_in_section
> offset_in_section
1896 && !have_sections_script
1897 && (sh_flags
& elfcpp::SHF_EXECINSTR
) != 0
1898 && object
->target()->has_code_fill())
1900 // We need to add some fill data. Using fill_list_ when
1901 // possible is an optimization, since we will often have fill
1902 // sections without input sections.
1903 off_t fill_len
= aligned_offset_in_section
- offset_in_section
;
1904 if (this->input_sections_
.empty())
1905 this->fills_
.push_back(Fill(offset_in_section
, fill_len
));
1908 // FIXME: When relaxing, the size needs to adjust to
1909 // maintain a constant alignment.
1910 std::string
fill_data(object
->target()->code_fill(fill_len
));
1911 Output_data_const
* odc
= new Output_data_const(fill_data
, 1);
1912 this->input_sections_
.push_back(Input_section(odc
));
1916 this->set_current_data_size_for_child(aligned_offset_in_section
1917 + shdr
.get_sh_size());
1919 // We need to keep track of this section if we are already keeping
1920 // track of sections, or if we are relaxing. Also, if this is a
1921 // section which requires sorting, or which may require sorting in
1922 // the future, we keep track of the sections.
1923 if (have_sections_script
1924 || !this->input_sections_
.empty()
1925 || this->may_sort_attached_input_sections()
1926 || this->must_sort_attached_input_sections()
1927 || parameters
->options().user_set_Map()
1928 || object
->target()->may_relax())
1929 this->input_sections_
.push_back(Input_section(object
, shndx
,
1933 return aligned_offset_in_section
;
1936 // Add arbitrary data to an output section.
1939 Output_section::add_output_section_data(Output_section_data
* posd
)
1941 Input_section
inp(posd
);
1942 this->add_output_section_data(&inp
);
1944 if (posd
->is_data_size_valid())
1946 off_t offset_in_section
= this->current_data_size_for_child();
1947 off_t aligned_offset_in_section
= align_address(offset_in_section
,
1949 this->set_current_data_size_for_child(aligned_offset_in_section
1950 + posd
->data_size());
1954 // Add arbitrary data to an output section by Input_section.
1957 Output_section::add_output_section_data(Input_section
* inp
)
1959 if (this->input_sections_
.empty())
1960 this->first_input_offset_
= this->current_data_size_for_child();
1962 this->input_sections_
.push_back(*inp
);
1964 uint64_t addralign
= inp
->addralign();
1965 if (addralign
> this->addralign_
)
1966 this->addralign_
= addralign
;
1968 inp
->set_output_section(this);
1971 // Add a merge section to an output section.
1974 Output_section::add_output_merge_section(Output_section_data
* posd
,
1975 bool is_string
, uint64_t entsize
)
1977 Input_section
inp(posd
, is_string
, entsize
);
1978 this->add_output_section_data(&inp
);
1981 // Add an input section to a SHF_MERGE section.
1984 Output_section::add_merge_input_section(Relobj
* object
, unsigned int shndx
,
1985 uint64_t flags
, uint64_t entsize
,
1988 bool is_string
= (flags
& elfcpp::SHF_STRINGS
) != 0;
1990 // We only merge strings if the alignment is not more than the
1991 // character size. This could be handled, but it's unusual.
1992 if (is_string
&& addralign
> entsize
)
1995 // We cannot restore merged input section states.
1996 gold_assert(this->checkpoint_
== NULL
);
1998 Input_section_list::iterator p
;
1999 for (p
= this->input_sections_
.begin();
2000 p
!= this->input_sections_
.end();
2002 if (p
->is_merge_section(is_string
, entsize
, addralign
))
2004 p
->add_input_section(object
, shndx
);
2008 // We handle the actual constant merging in Output_merge_data or
2009 // Output_merge_string_data.
2010 Output_section_data
* posd
;
2012 posd
= new Output_merge_data(entsize
, addralign
);
2018 posd
= new Output_merge_string
<char>(addralign
);
2021 posd
= new Output_merge_string
<uint16_t>(addralign
);
2024 posd
= new Output_merge_string
<uint32_t>(addralign
);
2031 this->add_output_merge_section(posd
, is_string
, entsize
);
2032 posd
->add_input_section(object
, shndx
);
2037 // Relax an existing input section.
2039 Output_section::relax_input_section(Output_relaxed_input_section
*psection
)
2041 Relobj
* relobj
= psection
->relobj();
2042 unsigned int shndx
= psection
->shndx();
2044 gold_assert(relobj
->target()->may_relax());
2046 // This is not very efficient if we a going to relax a number of sections
2047 // in an Output_section with lot of Input_sections.
2048 for (Input_section_list::iterator p
= this->input_sections_
.begin();
2049 p
!= this->input_sections_
.end();
2052 if (p
->is_input_section())
2054 if (p
->relobj() == relobj
&& p
->shndx() == shndx
)
2056 gold_assert(p
->addralign() == psection
->addralign());
2057 *p
= Input_section(psection
);
2061 else if (p
->is_relaxed_input_section())
2062 gold_assert(p
->relobj() != relobj
|| p
->shndx() != shndx
);
2067 // Update the output section flags based on input section flags.
2070 Output_section::update_flags_for_input_section(elfcpp::Elf_Xword flags
)
2072 // If we created the section with SHF_ALLOC clear, we set the
2073 // address. If we are now setting the SHF_ALLOC flag, we need to
2075 if ((this->flags_
& elfcpp::SHF_ALLOC
) == 0
2076 && (flags
& elfcpp::SHF_ALLOC
) != 0)
2077 this->mark_address_invalid();
2079 this->flags_
|= (flags
2080 & (elfcpp::SHF_WRITE
2082 | elfcpp::SHF_EXECINSTR
));
2085 // Given an address OFFSET relative to the start of input section
2086 // SHNDX in OBJECT, return whether this address is being included in
2087 // the final link. This should only be called if SHNDX in OBJECT has
2088 // a special mapping.
2091 Output_section::is_input_address_mapped(const Relobj
* object
,
2095 for (Input_section_list::const_iterator p
= this->input_sections_
.begin();
2096 p
!= this->input_sections_
.end();
2099 section_offset_type output_offset
;
2100 if (p
->output_offset(object
, shndx
, offset
, &output_offset
))
2101 return output_offset
!= -1;
2104 // By default we assume that the address is mapped. This should
2105 // only be called after we have passed all sections to Layout. At
2106 // that point we should know what we are discarding.
2110 // Given an address OFFSET relative to the start of input section
2111 // SHNDX in object OBJECT, return the output offset relative to the
2112 // start of the input section in the output section. This should only
2113 // be called if SHNDX in OBJECT has a special mapping.
2116 Output_section::output_offset(const Relobj
* object
, unsigned int shndx
,
2117 section_offset_type offset
) const
2119 // This can only be called meaningfully when layout is complete.
2120 gold_assert(Output_data::is_layout_complete());
2122 for (Input_section_list::const_iterator p
= this->input_sections_
.begin();
2123 p
!= this->input_sections_
.end();
2126 section_offset_type output_offset
;
2127 if (p
->output_offset(object
, shndx
, offset
, &output_offset
))
2128 return output_offset
;
2133 // Return the output virtual address of OFFSET relative to the start
2134 // of input section SHNDX in object OBJECT.
2137 Output_section::output_address(const Relobj
* object
, unsigned int shndx
,
2140 uint64_t addr
= this->address() + this->first_input_offset_
;
2141 for (Input_section_list::const_iterator p
= this->input_sections_
.begin();
2142 p
!= this->input_sections_
.end();
2145 addr
= align_address(addr
, p
->addralign());
2146 section_offset_type output_offset
;
2147 if (p
->output_offset(object
, shndx
, offset
, &output_offset
))
2149 if (output_offset
== -1)
2151 return addr
+ output_offset
;
2153 addr
+= p
->data_size();
2156 // If we get here, it means that we don't know the mapping for this
2157 // input section. This might happen in principle if
2158 // add_input_section were called before add_output_section_data.
2159 // But it should never actually happen.
2164 // Find the output address of the start of the merged section for
2165 // input section SHNDX in object OBJECT.
2168 Output_section::find_starting_output_address(const Relobj
* object
,
2170 uint64_t* paddr
) const
2172 uint64_t addr
= this->address() + this->first_input_offset_
;
2173 for (Input_section_list::const_iterator p
= this->input_sections_
.begin();
2174 p
!= this->input_sections_
.end();
2177 addr
= align_address(addr
, p
->addralign());
2179 // It would be nice if we could use the existing output_offset
2180 // method to get the output offset of input offset 0.
2181 // Unfortunately we don't know for sure that input offset 0 is
2183 if (p
->is_merge_section_for(object
, shndx
))
2189 addr
+= p
->data_size();
2192 // We couldn't find a merge output section for this input section.
2196 // Set the data size of an Output_section. This is where we handle
2197 // setting the addresses of any Output_section_data objects.
2200 Output_section::set_final_data_size()
2202 if (this->input_sections_
.empty())
2204 this->set_data_size(this->current_data_size_for_child());
2208 if (this->must_sort_attached_input_sections())
2209 this->sort_attached_input_sections();
2211 uint64_t address
= this->address();
2212 off_t startoff
= this->offset();
2213 off_t off
= startoff
+ this->first_input_offset_
;
2214 for (Input_section_list::iterator p
= this->input_sections_
.begin();
2215 p
!= this->input_sections_
.end();
2218 off
= align_address(off
, p
->addralign());
2219 p
->set_address_and_file_offset(address
+ (off
- startoff
), off
,
2221 off
+= p
->data_size();
2224 this->set_data_size(off
- startoff
);
2227 // Reset the address and file offset.
2230 Output_section::do_reset_address_and_file_offset()
2232 // An unallocated section has no address. Forcing this means that
2233 // we don't need special treatment for symbols defined in debug
2234 // sections. We do the same in the constructor.
2235 if ((this->flags_
& elfcpp::SHF_ALLOC
) == 0)
2236 this->set_address(0);
2238 for (Input_section_list::iterator p
= this->input_sections_
.begin();
2239 p
!= this->input_sections_
.end();
2241 p
->reset_address_and_file_offset();
2244 // Return true if address and file offset have the values after reset.
2247 Output_section::do_address_and_file_offset_have_reset_values() const
2249 if (this->is_offset_valid())
2252 // An unallocated section has address 0 after its construction or a reset.
2253 if ((this->flags_
& elfcpp::SHF_ALLOC
) == 0)
2254 return this->is_address_valid() && this->address() == 0;
2256 return !this->is_address_valid();
2259 // Set the TLS offset. Called only for SHT_TLS sections.
2262 Output_section::do_set_tls_offset(uint64_t tls_base
)
2264 this->tls_offset_
= this->address() - tls_base
;
2267 // In a few cases we need to sort the input sections attached to an
2268 // output section. This is used to implement the type of constructor
2269 // priority ordering implemented by the GNU linker, in which the
2270 // priority becomes part of the section name and the sections are
2271 // sorted by name. We only do this for an output section if we see an
2272 // attached input section matching ".ctor.*", ".dtor.*",
2273 // ".init_array.*" or ".fini_array.*".
2275 class Output_section::Input_section_sort_entry
2278 Input_section_sort_entry()
2279 : input_section_(), index_(-1U), section_has_name_(false),
2283 Input_section_sort_entry(const Input_section
& input_section
,
2285 : input_section_(input_section
), index_(index
),
2286 section_has_name_(input_section
.is_input_section()
2287 || input_section
.is_relaxed_input_section())
2289 if (this->section_has_name_
)
2291 // This is only called single-threaded from Layout::finalize,
2292 // so it is OK to lock. Unfortunately we have no way to pass
2294 const Task
* dummy_task
= reinterpret_cast<const Task
*>(-1);
2295 Object
* obj
= (input_section
.is_input_section()
2296 ? input_section
.relobj()
2297 : input_section
.relaxed_input_section()->relobj());
2298 Task_lock_obj
<Object
> tl(dummy_task
, obj
);
2300 // This is a slow operation, which should be cached in
2301 // Layout::layout if this becomes a speed problem.
2302 this->section_name_
= obj
->section_name(input_section
.shndx());
2306 // Return the Input_section.
2307 const Input_section
&
2308 input_section() const
2310 gold_assert(this->index_
!= -1U);
2311 return this->input_section_
;
2314 // The index of this entry in the original list. This is used to
2315 // make the sort stable.
2319 gold_assert(this->index_
!= -1U);
2320 return this->index_
;
2323 // Whether there is a section name.
2325 section_has_name() const
2326 { return this->section_has_name_
; }
2328 // The section name.
2330 section_name() const
2332 gold_assert(this->section_has_name_
);
2333 return this->section_name_
;
2336 // Return true if the section name has a priority. This is assumed
2337 // to be true if it has a dot after the initial dot.
2339 has_priority() const
2341 gold_assert(this->section_has_name_
);
2342 return this->section_name_
.find('.', 1);
2345 // Return true if this an input file whose base name matches
2346 // FILE_NAME. The base name must have an extension of ".o", and
2347 // must be exactly FILE_NAME.o or FILE_NAME, one character, ".o".
2348 // This is to match crtbegin.o as well as crtbeginS.o without
2349 // getting confused by other possibilities. Overall matching the
2350 // file name this way is a dreadful hack, but the GNU linker does it
2351 // in order to better support gcc, and we need to be compatible.
2353 match_file_name(const char* match_file_name
) const
2355 const std::string
& file_name(this->input_section_
.relobj()->name());
2356 const char* base_name
= lbasename(file_name
.c_str());
2357 size_t match_len
= strlen(match_file_name
);
2358 if (strncmp(base_name
, match_file_name
, match_len
) != 0)
2360 size_t base_len
= strlen(base_name
);
2361 if (base_len
!= match_len
+ 2 && base_len
!= match_len
+ 3)
2363 return memcmp(base_name
+ base_len
- 2, ".o", 2) == 0;
2367 // The Input_section we are sorting.
2368 Input_section input_section_
;
2369 // The index of this Input_section in the original list.
2370 unsigned int index_
;
2371 // Whether this Input_section has a section name--it won't if this
2372 // is some random Output_section_data.
2373 bool section_has_name_
;
2374 // The section name if there is one.
2375 std::string section_name_
;
2378 // Return true if S1 should come before S2 in the output section.
2381 Output_section::Input_section_sort_compare::operator()(
2382 const Output_section::Input_section_sort_entry
& s1
,
2383 const Output_section::Input_section_sort_entry
& s2
) const
2385 // crtbegin.o must come first.
2386 bool s1_begin
= s1
.match_file_name("crtbegin");
2387 bool s2_begin
= s2
.match_file_name("crtbegin");
2388 if (s1_begin
|| s2_begin
)
2394 return s1
.index() < s2
.index();
2397 // crtend.o must come last.
2398 bool s1_end
= s1
.match_file_name("crtend");
2399 bool s2_end
= s2
.match_file_name("crtend");
2400 if (s1_end
|| s2_end
)
2406 return s1
.index() < s2
.index();
2409 // We sort all the sections with no names to the end.
2410 if (!s1
.section_has_name() || !s2
.section_has_name())
2412 if (s1
.section_has_name())
2414 if (s2
.section_has_name())
2416 return s1
.index() < s2
.index();
2419 // A section with a priority follows a section without a priority.
2420 // The GNU linker does this for all but .init_array sections; until
2421 // further notice we'll assume that that is an mistake.
2422 bool s1_has_priority
= s1
.has_priority();
2423 bool s2_has_priority
= s2
.has_priority();
2424 if (s1_has_priority
&& !s2_has_priority
)
2426 if (!s1_has_priority
&& s2_has_priority
)
2429 // Otherwise we sort by name.
2430 int compare
= s1
.section_name().compare(s2
.section_name());
2434 // Otherwise we keep the input order.
2435 return s1
.index() < s2
.index();
2438 // Sort the input sections attached to an output section.
2441 Output_section::sort_attached_input_sections()
2443 if (this->attached_input_sections_are_sorted_
)
2446 if (this->checkpoint_
!= NULL
2447 && !this->checkpoint_
->input_sections_saved())
2448 this->checkpoint_
->save_input_sections();
2450 // The only thing we know about an input section is the object and
2451 // the section index. We need the section name. Recomputing this
2452 // is slow but this is an unusual case. If this becomes a speed
2453 // problem we can cache the names as required in Layout::layout.
2455 // We start by building a larger vector holding a copy of each
2456 // Input_section, plus its current index in the list and its name.
2457 std::vector
<Input_section_sort_entry
> sort_list
;
2460 for (Input_section_list::iterator p
= this->input_sections_
.begin();
2461 p
!= this->input_sections_
.end();
2463 sort_list
.push_back(Input_section_sort_entry(*p
, i
));
2465 // Sort the input sections.
2466 std::sort(sort_list
.begin(), sort_list
.end(), Input_section_sort_compare());
2468 // Copy the sorted input sections back to our list.
2469 this->input_sections_
.clear();
2470 for (std::vector
<Input_section_sort_entry
>::iterator p
= sort_list
.begin();
2471 p
!= sort_list
.end();
2473 this->input_sections_
.push_back(p
->input_section());
2475 // Remember that we sorted the input sections, since we might get
2477 this->attached_input_sections_are_sorted_
= true;
2480 // Write the section header to *OSHDR.
2482 template<int size
, bool big_endian
>
2484 Output_section::write_header(const Layout
* layout
,
2485 const Stringpool
* secnamepool
,
2486 elfcpp::Shdr_write
<size
, big_endian
>* oshdr
) const
2488 oshdr
->put_sh_name(secnamepool
->get_offset(this->name_
));
2489 oshdr
->put_sh_type(this->type_
);
2491 elfcpp::Elf_Xword flags
= this->flags_
;
2492 if (this->info_section_
!= NULL
&& this->info_uses_section_index_
)
2493 flags
|= elfcpp::SHF_INFO_LINK
;
2494 oshdr
->put_sh_flags(flags
);
2496 oshdr
->put_sh_addr(this->address());
2497 oshdr
->put_sh_offset(this->offset());
2498 oshdr
->put_sh_size(this->data_size());
2499 if (this->link_section_
!= NULL
)
2500 oshdr
->put_sh_link(this->link_section_
->out_shndx());
2501 else if (this->should_link_to_symtab_
)
2502 oshdr
->put_sh_link(layout
->symtab_section()->out_shndx());
2503 else if (this->should_link_to_dynsym_
)
2504 oshdr
->put_sh_link(layout
->dynsym_section()->out_shndx());
2506 oshdr
->put_sh_link(this->link_
);
2508 elfcpp::Elf_Word info
;
2509 if (this->info_section_
!= NULL
)
2511 if (this->info_uses_section_index_
)
2512 info
= this->info_section_
->out_shndx();
2514 info
= this->info_section_
->symtab_index();
2516 else if (this->info_symndx_
!= NULL
)
2517 info
= this->info_symndx_
->symtab_index();
2520 oshdr
->put_sh_info(info
);
2522 oshdr
->put_sh_addralign(this->addralign_
);
2523 oshdr
->put_sh_entsize(this->entsize_
);
2526 // Write out the data. For input sections the data is written out by
2527 // Object::relocate, but we have to handle Output_section_data objects
2531 Output_section::do_write(Output_file
* of
)
2533 gold_assert(!this->requires_postprocessing());
2535 off_t output_section_file_offset
= this->offset();
2536 for (Fill_list::iterator p
= this->fills_
.begin();
2537 p
!= this->fills_
.end();
2540 std::string
fill_data(parameters
->target().code_fill(p
->length()));
2541 of
->write(output_section_file_offset
+ p
->section_offset(),
2542 fill_data
.data(), fill_data
.size());
2545 for (Input_section_list::iterator p
= this->input_sections_
.begin();
2546 p
!= this->input_sections_
.end();
2551 // If a section requires postprocessing, create the buffer to use.
2554 Output_section::create_postprocessing_buffer()
2556 gold_assert(this->requires_postprocessing());
2558 if (this->postprocessing_buffer_
!= NULL
)
2561 if (!this->input_sections_
.empty())
2563 off_t off
= this->first_input_offset_
;
2564 for (Input_section_list::iterator p
= this->input_sections_
.begin();
2565 p
!= this->input_sections_
.end();
2568 off
= align_address(off
, p
->addralign());
2569 p
->finalize_data_size();
2570 off
+= p
->data_size();
2572 this->set_current_data_size_for_child(off
);
2575 off_t buffer_size
= this->current_data_size_for_child();
2576 this->postprocessing_buffer_
= new unsigned char[buffer_size
];
2579 // Write all the data of an Output_section into the postprocessing
2580 // buffer. This is used for sections which require postprocessing,
2581 // such as compression. Input sections are handled by
2582 // Object::Relocate.
2585 Output_section::write_to_postprocessing_buffer()
2587 gold_assert(this->requires_postprocessing());
2589 unsigned char* buffer
= this->postprocessing_buffer();
2590 for (Fill_list::iterator p
= this->fills_
.begin();
2591 p
!= this->fills_
.end();
2594 std::string
fill_data(parameters
->target().code_fill(p
->length()));
2595 memcpy(buffer
+ p
->section_offset(), fill_data
.data(),
2599 off_t off
= this->first_input_offset_
;
2600 for (Input_section_list::iterator p
= this->input_sections_
.begin();
2601 p
!= this->input_sections_
.end();
2604 off
= align_address(off
, p
->addralign());
2605 p
->write_to_buffer(buffer
+ off
);
2606 off
+= p
->data_size();
2610 // Get the input sections for linker script processing. We leave
2611 // behind the Output_section_data entries. Note that this may be
2612 // slightly incorrect for merge sections. We will leave them behind,
2613 // but it is possible that the script says that they should follow
2614 // some other input sections, as in:
2615 // .rodata { *(.rodata) *(.rodata.cst*) }
2616 // For that matter, we don't handle this correctly:
2617 // .rodata { foo.o(.rodata.cst*) *(.rodata.cst*) }
2618 // With luck this will never matter.
2621 Output_section::get_input_sections(
2623 const std::string
& fill
,
2624 std::list
<Simple_input_section
>* input_sections
)
2626 if (this->checkpoint_
!= NULL
2627 && !this->checkpoint_
->input_sections_saved())
2628 this->checkpoint_
->save_input_sections();
2630 uint64_t orig_address
= address
;
2632 address
= align_address(address
, this->addralign());
2634 Input_section_list remaining
;
2635 for (Input_section_list::iterator p
= this->input_sections_
.begin();
2636 p
!= this->input_sections_
.end();
2639 if (p
->is_input_section())
2640 input_sections
->push_back(Simple_input_section(p
->relobj(),
2642 else if (p
->is_relaxed_input_section())
2643 input_sections
->push_back(
2644 Simple_input_section(p
->relaxed_input_section()));
2647 uint64_t aligned_address
= align_address(address
, p
->addralign());
2648 if (aligned_address
!= address
&& !fill
.empty())
2650 section_size_type length
=
2651 convert_to_section_size_type(aligned_address
- address
);
2652 std::string this_fill
;
2653 this_fill
.reserve(length
);
2654 while (this_fill
.length() + fill
.length() <= length
)
2656 if (this_fill
.length() < length
)
2657 this_fill
.append(fill
, 0, length
- this_fill
.length());
2659 Output_section_data
* posd
= new Output_data_const(this_fill
, 0);
2660 remaining
.push_back(Input_section(posd
));
2662 address
= aligned_address
;
2664 remaining
.push_back(*p
);
2666 p
->finalize_data_size();
2667 address
+= p
->data_size();
2671 this->input_sections_
.swap(remaining
);
2672 this->first_input_offset_
= 0;
2674 uint64_t data_size
= address
- orig_address
;
2675 this->set_current_data_size_for_child(data_size
);
2679 // Add an input section from a script.
2682 Output_section::add_input_section_for_script(const Simple_input_section
& sis
,
2686 if (addralign
> this->addralign_
)
2687 this->addralign_
= addralign
;
2689 off_t offset_in_section
= this->current_data_size_for_child();
2690 off_t aligned_offset_in_section
= align_address(offset_in_section
,
2693 this->set_current_data_size_for_child(aligned_offset_in_section
2697 (sis
.is_relaxed_input_section()
2698 ? Input_section(sis
.relaxed_input_section())
2699 : Input_section(sis
.relobj(), sis
.shndx(), data_size
, addralign
));
2700 this->input_sections_
.push_back(is
);
2706 Output_section::save_states()
2708 gold_assert(this->checkpoint_
== NULL
);
2709 Checkpoint_output_section
* checkpoint
=
2710 new Checkpoint_output_section(this->addralign_
, this->flags_
,
2711 this->input_sections_
,
2712 this->first_input_offset_
,
2713 this->attached_input_sections_are_sorted_
);
2714 this->checkpoint_
= checkpoint
;
2715 gold_assert(this->fills_
.empty());
2719 Output_section::restore_states()
2721 gold_assert(this->checkpoint_
!= NULL
);
2722 Checkpoint_output_section
* checkpoint
= this->checkpoint_
;
2724 this->addralign_
= checkpoint
->addralign();
2725 this->flags_
= checkpoint
->flags();
2726 this->first_input_offset_
= checkpoint
->first_input_offset();
2728 if (!checkpoint
->input_sections_saved())
2730 // If we have not copied the input sections, just resize it.
2731 size_t old_size
= checkpoint
->input_sections_size();
2732 gold_assert(this->input_sections_
.size() >= old_size
);
2733 this->input_sections_
.resize(old_size
);
2737 // We need to copy the whole list. This is not efficient for
2738 // extremely large output with hundreads of thousands of input
2739 // objects. We may need to re-think how we should pass sections
2741 this->input_sections_
= checkpoint
->input_sections();
2744 this->attached_input_sections_are_sorted_
=
2745 checkpoint
->attached_input_sections_are_sorted();
2748 // Print to the map file.
2751 Output_section::do_print_to_mapfile(Mapfile
* mapfile
) const
2753 mapfile
->print_output_section(this);
2755 for (Input_section_list::const_iterator p
= this->input_sections_
.begin();
2756 p
!= this->input_sections_
.end();
2758 p
->print_to_mapfile(mapfile
);
2761 // Print stats for merge sections to stderr.
2764 Output_section::print_merge_stats()
2766 Input_section_list::iterator p
;
2767 for (p
= this->input_sections_
.begin();
2768 p
!= this->input_sections_
.end();
2770 p
->print_merge_stats(this->name_
);
2773 // Output segment methods.
2775 Output_segment::Output_segment(elfcpp::Elf_Word type
, elfcpp::Elf_Word flags
)
2787 is_max_align_known_(false),
2788 are_addresses_set_(false),
2789 is_large_data_segment_(false)
2793 // Add an Output_section to an Output_segment.
2796 Output_segment::add_output_section(Output_section
* os
,
2797 elfcpp::Elf_Word seg_flags
)
2799 gold_assert((os
->flags() & elfcpp::SHF_ALLOC
) != 0);
2800 gold_assert(!this->is_max_align_known_
);
2801 gold_assert(os
->is_large_data_section() == this->is_large_data_segment());
2803 // Update the segment flags.
2804 this->flags_
|= seg_flags
;
2806 Output_segment::Output_data_list
* pdl
;
2807 if (os
->type() == elfcpp::SHT_NOBITS
)
2808 pdl
= &this->output_bss_
;
2810 pdl
= &this->output_data_
;
2812 // So that PT_NOTE segments will work correctly, we need to ensure
2813 // that all SHT_NOTE sections are adjacent. This will normally
2814 // happen automatically, because all the SHT_NOTE input sections
2815 // will wind up in the same output section. However, it is possible
2816 // for multiple SHT_NOTE input sections to have different section
2817 // flags, and thus be in different output sections, but for the
2818 // different section flags to map into the same segment flags and
2819 // thus the same output segment.
2821 // Note that while there may be many input sections in an output
2822 // section, there are normally only a few output sections in an
2823 // output segment. This loop is expected to be fast.
2825 if (os
->type() == elfcpp::SHT_NOTE
&& !pdl
->empty())
2827 Output_segment::Output_data_list::iterator p
= pdl
->end();
2831 if ((*p
)->is_section_type(elfcpp::SHT_NOTE
))
2838 while (p
!= pdl
->begin());
2841 // Similarly, so that PT_TLS segments will work, we need to group
2842 // SHF_TLS sections. An SHF_TLS/SHT_NOBITS section is a special
2843 // case: we group the SHF_TLS/SHT_NOBITS sections right after the
2844 // SHF_TLS/SHT_PROGBITS sections. This lets us set up PT_TLS
2845 // correctly. SHF_TLS sections get added to both a PT_LOAD segment
2846 // and the PT_TLS segment -- we do this grouping only for the
2848 if (this->type_
!= elfcpp::PT_TLS
2849 && (os
->flags() & elfcpp::SHF_TLS
) != 0)
2851 pdl
= &this->output_data_
;
2852 bool nobits
= os
->type() == elfcpp::SHT_NOBITS
;
2853 bool sawtls
= false;
2854 Output_segment::Output_data_list::iterator p
= pdl
->end();
2859 if ((*p
)->is_section_flag_set(elfcpp::SHF_TLS
))
2862 // Put a NOBITS section after the first TLS section.
2863 // Put a PROGBITS section after the first TLS/PROGBITS
2865 insert
= nobits
|| !(*p
)->is_section_type(elfcpp::SHT_NOBITS
);
2869 // If we've gone past the TLS sections, but we've seen a
2870 // TLS section, then we need to insert this section now.
2881 while (p
!= pdl
->begin());
2883 // There are no TLS sections yet; put this one at the requested
2884 // location in the section list.
2887 // For the PT_GNU_RELRO segment, we need to group relro sections,
2888 // and we need to put them before any non-relro sections. Also,
2889 // relro local sections go before relro non-local sections.
2890 if (parameters
->options().relro() && os
->is_relro())
2892 gold_assert(pdl
== &this->output_data_
);
2893 Output_segment::Output_data_list::iterator p
;
2894 for (p
= pdl
->begin(); p
!= pdl
->end(); ++p
)
2896 if (!(*p
)->is_section())
2899 Output_section
* pos
= (*p
)->output_section();
2900 if (!pos
->is_relro()
2901 || (os
->is_relro_local() && !pos
->is_relro_local()))
2909 // Small data sections go at the end of the list of data sections.
2910 // If OS is not small, and there are small sections, we have to
2911 // insert it before the first small section.
2912 if (os
->type() != elfcpp::SHT_NOBITS
2913 && !os
->is_small_section()
2915 && pdl
->back()->is_section()
2916 && pdl
->back()->output_section()->is_small_section())
2918 for (Output_segment::Output_data_list::iterator p
= pdl
->begin();
2922 if ((*p
)->is_section()
2923 && (*p
)->output_section()->is_small_section())
2932 // A small BSS section goes at the start of the BSS sections, after
2933 // other small BSS sections.
2934 if (os
->type() == elfcpp::SHT_NOBITS
&& os
->is_small_section())
2936 for (Output_segment::Output_data_list::iterator p
= pdl
->begin();
2940 if (!(*p
)->is_section()
2941 || !(*p
)->output_section()->is_small_section())
2949 // A large BSS section goes at the end of the BSS sections, which
2950 // means that one that is not large must come before the first large
2952 if (os
->type() == elfcpp::SHT_NOBITS
2953 && !os
->is_large_section()
2955 && pdl
->back()->is_section()
2956 && pdl
->back()->output_section()->is_large_section())
2958 for (Output_segment::Output_data_list::iterator p
= pdl
->begin();
2962 if ((*p
)->is_section()
2963 && (*p
)->output_section()->is_large_section())
2975 // Remove an Output_section from this segment. It is an error if it
2979 Output_segment::remove_output_section(Output_section
* os
)
2981 // We only need this for SHT_PROGBITS.
2982 gold_assert(os
->type() == elfcpp::SHT_PROGBITS
);
2983 for (Output_data_list::iterator p
= this->output_data_
.begin();
2984 p
!= this->output_data_
.end();
2989 this->output_data_
.erase(p
);
2996 // Add an Output_data (which is not an Output_section) to the start of
3000 Output_segment::add_initial_output_data(Output_data
* od
)
3002 gold_assert(!this->is_max_align_known_
);
3003 this->output_data_
.push_front(od
);
3006 // Return whether the first data section is a relro section.
3009 Output_segment::is_first_section_relro() const
3011 return (!this->output_data_
.empty()
3012 && this->output_data_
.front()->is_section()
3013 && this->output_data_
.front()->output_section()->is_relro());
3016 // Return the maximum alignment of the Output_data in Output_segment.
3019 Output_segment::maximum_alignment()
3021 if (!this->is_max_align_known_
)
3025 addralign
= Output_segment::maximum_alignment_list(&this->output_data_
);
3026 if (addralign
> this->max_align_
)
3027 this->max_align_
= addralign
;
3029 addralign
= Output_segment::maximum_alignment_list(&this->output_bss_
);
3030 if (addralign
> this->max_align_
)
3031 this->max_align_
= addralign
;
3033 // If -z relro is in effect, and the first section in this
3034 // segment is a relro section, then the segment must be aligned
3035 // to at least the common page size. This ensures that the
3036 // PT_GNU_RELRO segment will start at a page boundary.
3037 if (this->type_
== elfcpp::PT_LOAD
3038 && parameters
->options().relro()
3039 && this->is_first_section_relro())
3041 addralign
= parameters
->target().common_pagesize();
3042 if (addralign
> this->max_align_
)
3043 this->max_align_
= addralign
;
3046 this->is_max_align_known_
= true;
3049 return this->max_align_
;
3052 // Return the maximum alignment of a list of Output_data.
3055 Output_segment::maximum_alignment_list(const Output_data_list
* pdl
)
3058 for (Output_data_list::const_iterator p
= pdl
->begin();
3062 uint64_t addralign
= (*p
)->addralign();
3063 if (addralign
> ret
)
3069 // Return the number of dynamic relocs applied to this segment.
3072 Output_segment::dynamic_reloc_count() const
3074 return (this->dynamic_reloc_count_list(&this->output_data_
)
3075 + this->dynamic_reloc_count_list(&this->output_bss_
));
3078 // Return the number of dynamic relocs applied to an Output_data_list.
3081 Output_segment::dynamic_reloc_count_list(const Output_data_list
* pdl
) const
3083 unsigned int count
= 0;
3084 for (Output_data_list::const_iterator p
= pdl
->begin();
3087 count
+= (*p
)->dynamic_reloc_count();
3091 // Set the section addresses for an Output_segment. If RESET is true,
3092 // reset the addresses first. ADDR is the address and *POFF is the
3093 // file offset. Set the section indexes starting with *PSHNDX.
3094 // Return the address of the immediately following segment. Update
3095 // *POFF and *PSHNDX.
3098 Output_segment::set_section_addresses(const Layout
* layout
, bool reset
,
3099 uint64_t addr
, off_t
* poff
,
3100 unsigned int* pshndx
)
3102 gold_assert(this->type_
== elfcpp::PT_LOAD
);
3104 if (!reset
&& this->are_addresses_set_
)
3106 gold_assert(this->paddr_
== addr
);
3107 addr
= this->vaddr_
;
3111 this->vaddr_
= addr
;
3112 this->paddr_
= addr
;
3113 this->are_addresses_set_
= true;
3116 bool in_tls
= false;
3118 bool in_relro
= (parameters
->options().relro()
3119 && this->is_first_section_relro());
3121 off_t orig_off
= *poff
;
3122 this->offset_
= orig_off
;
3124 addr
= this->set_section_list_addresses(layout
, reset
, &this->output_data_
,
3125 addr
, poff
, pshndx
, &in_tls
,
3127 this->filesz_
= *poff
- orig_off
;
3131 uint64_t ret
= this->set_section_list_addresses(layout
, reset
,
3134 &in_tls
, &in_relro
);
3136 // If the last section was a TLS section, align upward to the
3137 // alignment of the TLS segment, so that the overall size of the TLS
3138 // segment is aligned.
3141 uint64_t segment_align
= layout
->tls_segment()->maximum_alignment();
3142 *poff
= align_address(*poff
, segment_align
);
3145 // If all the sections were relro sections, align upward to the
3146 // common page size.
3149 uint64_t page_align
= parameters
->target().common_pagesize();
3150 *poff
= align_address(*poff
, page_align
);
3153 this->memsz_
= *poff
- orig_off
;
3155 // Ignore the file offset adjustments made by the BSS Output_data
3162 // Set the addresses and file offsets in a list of Output_data
3166 Output_segment::set_section_list_addresses(const Layout
* layout
, bool reset
,
3167 Output_data_list
* pdl
,
3168 uint64_t addr
, off_t
* poff
,
3169 unsigned int* pshndx
,
3170 bool* in_tls
, bool* in_relro
)
3172 off_t startoff
= *poff
;
3174 off_t off
= startoff
;
3175 for (Output_data_list::iterator p
= pdl
->begin();
3180 (*p
)->reset_address_and_file_offset();
3182 // When using a linker script the section will most likely
3183 // already have an address.
3184 if (!(*p
)->is_address_valid())
3186 uint64_t align
= (*p
)->addralign();
3188 if ((*p
)->is_section_flag_set(elfcpp::SHF_TLS
))
3190 // Give the first TLS section the alignment of the
3191 // entire TLS segment. Otherwise the TLS segment as a
3192 // whole may be misaligned.
3195 Output_segment
* tls_segment
= layout
->tls_segment();
3196 gold_assert(tls_segment
!= NULL
);
3197 uint64_t segment_align
= tls_segment
->maximum_alignment();
3198 gold_assert(segment_align
>= align
);
3199 align
= segment_align
;
3206 // If this is the first section after the TLS segment,
3207 // align it to at least the alignment of the TLS
3208 // segment, so that the size of the overall TLS segment
3212 uint64_t segment_align
=
3213 layout
->tls_segment()->maximum_alignment();
3214 if (segment_align
> align
)
3215 align
= segment_align
;
3221 // If this is a non-relro section after a relro section,
3222 // align it to a common page boundary so that the dynamic
3223 // linker has a page to mark as read-only.
3225 && (!(*p
)->is_section()
3226 || !(*p
)->output_section()->is_relro()))
3228 uint64_t page_align
= parameters
->target().common_pagesize();
3229 if (page_align
> align
)
3234 off
= align_address(off
, align
);
3235 (*p
)->set_address_and_file_offset(addr
+ (off
- startoff
), off
);
3239 // The script may have inserted a skip forward, but it
3240 // better not have moved backward.
3241 gold_assert((*p
)->address() >= addr
+ (off
- startoff
));
3242 off
+= (*p
)->address() - (addr
+ (off
- startoff
));
3243 (*p
)->set_file_offset(off
);
3244 (*p
)->finalize_data_size();
3247 // We want to ignore the size of a SHF_TLS or SHT_NOBITS
3248 // section. Such a section does not affect the size of a
3250 if (!(*p
)->is_section_flag_set(elfcpp::SHF_TLS
)
3251 || !(*p
)->is_section_type(elfcpp::SHT_NOBITS
))
3252 off
+= (*p
)->data_size();
3254 if ((*p
)->is_section())
3256 (*p
)->set_out_shndx(*pshndx
);
3262 return addr
+ (off
- startoff
);
3265 // For a non-PT_LOAD segment, set the offset from the sections, if
3269 Output_segment::set_offset()
3271 gold_assert(this->type_
!= elfcpp::PT_LOAD
);
3273 gold_assert(!this->are_addresses_set_
);
3275 if (this->output_data_
.empty() && this->output_bss_
.empty())
3279 this->are_addresses_set_
= true;
3281 this->min_p_align_
= 0;
3287 const Output_data
* first
;
3288 if (this->output_data_
.empty())
3289 first
= this->output_bss_
.front();
3291 first
= this->output_data_
.front();
3292 this->vaddr_
= first
->address();
3293 this->paddr_
= (first
->has_load_address()
3294 ? first
->load_address()
3296 this->are_addresses_set_
= true;
3297 this->offset_
= first
->offset();
3299 if (this->output_data_
.empty())
3303 const Output_data
* last_data
= this->output_data_
.back();
3304 this->filesz_
= (last_data
->address()
3305 + last_data
->data_size()
3309 const Output_data
* last
;
3310 if (this->output_bss_
.empty())
3311 last
= this->output_data_
.back();
3313 last
= this->output_bss_
.back();
3314 this->memsz_
= (last
->address()
3318 // If this is a TLS segment, align the memory size. The code in
3319 // set_section_list ensures that the section after the TLS segment
3320 // is aligned to give us room.
3321 if (this->type_
== elfcpp::PT_TLS
)
3323 uint64_t segment_align
= this->maximum_alignment();
3324 gold_assert(this->vaddr_
== align_address(this->vaddr_
, segment_align
));
3325 this->memsz_
= align_address(this->memsz_
, segment_align
);
3328 // If this is a RELRO segment, align the memory size. The code in
3329 // set_section_list ensures that the section after the RELRO segment
3330 // is aligned to give us room.
3331 if (this->type_
== elfcpp::PT_GNU_RELRO
)
3333 uint64_t page_align
= parameters
->target().common_pagesize();
3334 gold_assert(this->vaddr_
== align_address(this->vaddr_
, page_align
));
3335 this->memsz_
= align_address(this->memsz_
, page_align
);
3339 // Set the TLS offsets of the sections in the PT_TLS segment.
3342 Output_segment::set_tls_offsets()
3344 gold_assert(this->type_
== elfcpp::PT_TLS
);
3346 for (Output_data_list::iterator p
= this->output_data_
.begin();
3347 p
!= this->output_data_
.end();
3349 (*p
)->set_tls_offset(this->vaddr_
);
3351 for (Output_data_list::iterator p
= this->output_bss_
.begin();
3352 p
!= this->output_bss_
.end();
3354 (*p
)->set_tls_offset(this->vaddr_
);
3357 // Return the address of the first section.
3360 Output_segment::first_section_load_address() const
3362 for (Output_data_list::const_iterator p
= this->output_data_
.begin();
3363 p
!= this->output_data_
.end();
3365 if ((*p
)->is_section())
3366 return (*p
)->has_load_address() ? (*p
)->load_address() : (*p
)->address();
3368 for (Output_data_list::const_iterator p
= this->output_bss_
.begin();
3369 p
!= this->output_bss_
.end();
3371 if ((*p
)->is_section())
3372 return (*p
)->has_load_address() ? (*p
)->load_address() : (*p
)->address();
3377 // Return the number of Output_sections in an Output_segment.
3380 Output_segment::output_section_count() const
3382 return (this->output_section_count_list(&this->output_data_
)
3383 + this->output_section_count_list(&this->output_bss_
));
3386 // Return the number of Output_sections in an Output_data_list.
3389 Output_segment::output_section_count_list(const Output_data_list
* pdl
) const
3391 unsigned int count
= 0;
3392 for (Output_data_list::const_iterator p
= pdl
->begin();
3396 if ((*p
)->is_section())
3402 // Return the section attached to the list segment with the lowest
3403 // load address. This is used when handling a PHDRS clause in a
3407 Output_segment::section_with_lowest_load_address() const
3409 Output_section
* found
= NULL
;
3410 uint64_t found_lma
= 0;
3411 this->lowest_load_address_in_list(&this->output_data_
, &found
, &found_lma
);
3413 Output_section
* found_data
= found
;
3414 this->lowest_load_address_in_list(&this->output_bss_
, &found
, &found_lma
);
3415 if (found
!= found_data
&& found_data
!= NULL
)
3417 gold_error(_("nobits section %s may not precede progbits section %s "
3419 found
->name(), found_data
->name());
3426 // Look through a list for a section with a lower load address.
3429 Output_segment::lowest_load_address_in_list(const Output_data_list
* pdl
,
3430 Output_section
** found
,
3431 uint64_t* found_lma
) const
3433 for (Output_data_list::const_iterator p
= pdl
->begin();
3437 if (!(*p
)->is_section())
3439 Output_section
* os
= static_cast<Output_section
*>(*p
);
3440 uint64_t lma
= (os
->has_load_address()
3441 ? os
->load_address()
3443 if (*found
== NULL
|| lma
< *found_lma
)
3451 // Write the segment data into *OPHDR.
3453 template<int size
, bool big_endian
>
3455 Output_segment::write_header(elfcpp::Phdr_write
<size
, big_endian
>* ophdr
)
3457 ophdr
->put_p_type(this->type_
);
3458 ophdr
->put_p_offset(this->offset_
);
3459 ophdr
->put_p_vaddr(this->vaddr_
);
3460 ophdr
->put_p_paddr(this->paddr_
);
3461 ophdr
->put_p_filesz(this->filesz_
);
3462 ophdr
->put_p_memsz(this->memsz_
);
3463 ophdr
->put_p_flags(this->flags_
);
3464 ophdr
->put_p_align(std::max(this->min_p_align_
, this->maximum_alignment()));
3467 // Write the section headers into V.
3469 template<int size
, bool big_endian
>
3471 Output_segment::write_section_headers(const Layout
* layout
,
3472 const Stringpool
* secnamepool
,
3474 unsigned int *pshndx
) const
3476 // Every section that is attached to a segment must be attached to a
3477 // PT_LOAD segment, so we only write out section headers for PT_LOAD
3479 if (this->type_
!= elfcpp::PT_LOAD
)
3482 v
= this->write_section_headers_list
<size
, big_endian
>(layout
, secnamepool
,
3483 &this->output_data_
,
3485 v
= this->write_section_headers_list
<size
, big_endian
>(layout
, secnamepool
,
3491 template<int size
, bool big_endian
>
3493 Output_segment::write_section_headers_list(const Layout
* layout
,
3494 const Stringpool
* secnamepool
,
3495 const Output_data_list
* pdl
,
3497 unsigned int* pshndx
) const
3499 const int shdr_size
= elfcpp::Elf_sizes
<size
>::shdr_size
;
3500 for (Output_data_list::const_iterator p
= pdl
->begin();
3504 if ((*p
)->is_section())
3506 const Output_section
* ps
= static_cast<const Output_section
*>(*p
);
3507 gold_assert(*pshndx
== ps
->out_shndx());
3508 elfcpp::Shdr_write
<size
, big_endian
> oshdr(v
);
3509 ps
->write_header(layout
, secnamepool
, &oshdr
);
3517 // Print the output sections to the map file.
3520 Output_segment::print_sections_to_mapfile(Mapfile
* mapfile
) const
3522 if (this->type() != elfcpp::PT_LOAD
)
3524 this->print_section_list_to_mapfile(mapfile
, &this->output_data_
);
3525 this->print_section_list_to_mapfile(mapfile
, &this->output_bss_
);
3528 // Print an output section list to the map file.
3531 Output_segment::print_section_list_to_mapfile(Mapfile
* mapfile
,
3532 const Output_data_list
* pdl
) const
3534 for (Output_data_list::const_iterator p
= pdl
->begin();
3537 (*p
)->print_to_mapfile(mapfile
);
3540 // Output_file methods.
3542 Output_file::Output_file(const char* name
)
3547 map_is_anonymous_(false),
3548 is_temporary_(false)
3552 // Try to open an existing file. Returns false if the file doesn't
3553 // exist, has a size of 0 or can't be mmapped.
3556 Output_file::open_for_modification()
3558 // The name "-" means "stdout".
3559 if (strcmp(this->name_
, "-") == 0)
3562 // Don't bother opening files with a size of zero.
3564 if (::stat(this->name_
, &s
) != 0 || s
.st_size
== 0)
3567 int o
= open_descriptor(-1, this->name_
, O_RDWR
, 0);
3569 gold_fatal(_("%s: open: %s"), this->name_
, strerror(errno
));
3571 this->file_size_
= s
.st_size
;
3573 // If the file can't be mmapped, copying the content to an anonymous
3574 // map will probably negate the performance benefits of incremental
3575 // linking. This could be helped by using views and loading only
3576 // the necessary parts, but this is not supported as of now.
3577 if (!this->map_no_anonymous())
3579 release_descriptor(o
, true);
3581 this->file_size_
= 0;
3588 // Open the output file.
3591 Output_file::open(off_t file_size
)
3593 this->file_size_
= file_size
;
3595 // Unlink the file first; otherwise the open() may fail if the file
3596 // is busy (e.g. it's an executable that's currently being executed).
3598 // However, the linker may be part of a system where a zero-length
3599 // file is created for it to write to, with tight permissions (gcc
3600 // 2.95 did something like this). Unlinking the file would work
3601 // around those permission controls, so we only unlink if the file
3602 // has a non-zero size. We also unlink only regular files to avoid
3603 // trouble with directories/etc.
3605 // If we fail, continue; this command is merely a best-effort attempt
3606 // to improve the odds for open().
3608 // We let the name "-" mean "stdout"
3609 if (!this->is_temporary_
)
3611 if (strcmp(this->name_
, "-") == 0)
3612 this->o_
= STDOUT_FILENO
;
3616 if (::stat(this->name_
, &s
) == 0
3617 && (S_ISREG (s
.st_mode
) || S_ISLNK (s
.st_mode
)))
3620 ::unlink(this->name_
);
3621 else if (!parameters
->options().relocatable())
3623 // If we don't unlink the existing file, add execute
3624 // permission where read permissions already exist
3625 // and where the umask permits.
3626 int mask
= ::umask(0);
3628 s
.st_mode
|= (s
.st_mode
& 0444) >> 2;
3629 ::chmod(this->name_
, s
.st_mode
& ~mask
);
3633 int mode
= parameters
->options().relocatable() ? 0666 : 0777;
3634 int o
= open_descriptor(-1, this->name_
, O_RDWR
| O_CREAT
| O_TRUNC
,
3637 gold_fatal(_("%s: open: %s"), this->name_
, strerror(errno
));
3645 // Resize the output file.
3648 Output_file::resize(off_t file_size
)
3650 // If the mmap is mapping an anonymous memory buffer, this is easy:
3651 // just mremap to the new size. If it's mapping to a file, we want
3652 // to unmap to flush to the file, then remap after growing the file.
3653 if (this->map_is_anonymous_
)
3655 void* base
= ::mremap(this->base_
, this->file_size_
, file_size
,
3657 if (base
== MAP_FAILED
)
3658 gold_fatal(_("%s: mremap: %s"), this->name_
, strerror(errno
));
3659 this->base_
= static_cast<unsigned char*>(base
);
3660 this->file_size_
= file_size
;
3665 this->file_size_
= file_size
;
3666 if (!this->map_no_anonymous())
3667 gold_fatal(_("%s: mmap: %s"), this->name_
, strerror(errno
));
3671 // Map an anonymous block of memory which will later be written to the
3672 // file. Return whether the map succeeded.
3675 Output_file::map_anonymous()
3677 void* base
= ::mmap(NULL
, this->file_size_
, PROT_READ
| PROT_WRITE
,
3678 MAP_PRIVATE
| MAP_ANONYMOUS
, -1, 0);
3679 if (base
!= MAP_FAILED
)
3681 this->map_is_anonymous_
= true;
3682 this->base_
= static_cast<unsigned char*>(base
);
3688 // Map the file into memory. Return whether the mapping succeeded.
3691 Output_file::map_no_anonymous()
3693 const int o
= this->o_
;
3695 // If the output file is not a regular file, don't try to mmap it;
3696 // instead, we'll mmap a block of memory (an anonymous buffer), and
3697 // then later write the buffer to the file.
3699 struct stat statbuf
;
3700 if (o
== STDOUT_FILENO
|| o
== STDERR_FILENO
3701 || ::fstat(o
, &statbuf
) != 0
3702 || !S_ISREG(statbuf
.st_mode
)
3703 || this->is_temporary_
)
3706 // Ensure that we have disk space available for the file. If we
3707 // don't do this, it is possible that we will call munmap, close,
3708 // and exit with dirty buffers still in the cache with no assigned
3709 // disk blocks. If the disk is out of space at that point, the
3710 // output file will wind up incomplete, but we will have already
3711 // exited. The alternative to fallocate would be to use fdatasync,
3712 // but that would be a more significant performance hit.
3713 if (::posix_fallocate(o
, 0, this->file_size_
) < 0)
3714 gold_fatal(_("%s: %s"), this->name_
, strerror(errno
));
3716 // Map the file into memory.
3717 base
= ::mmap(NULL
, this->file_size_
, PROT_READ
| PROT_WRITE
,
3720 // The mmap call might fail because of file system issues: the file
3721 // system might not support mmap at all, or it might not support
3722 // mmap with PROT_WRITE.
3723 if (base
== MAP_FAILED
)
3726 this->map_is_anonymous_
= false;
3727 this->base_
= static_cast<unsigned char*>(base
);
3731 // Map the file into memory.
3736 if (this->map_no_anonymous())
3739 // The mmap call might fail because of file system issues: the file
3740 // system might not support mmap at all, or it might not support
3741 // mmap with PROT_WRITE. I'm not sure which errno values we will
3742 // see in all cases, so if the mmap fails for any reason and we
3743 // don't care about file contents, try for an anonymous map.
3744 if (this->map_anonymous())
3747 gold_fatal(_("%s: mmap: failed to allocate %lu bytes for output file: %s"),
3748 this->name_
, static_cast<unsigned long>(this->file_size_
),
3752 // Unmap the file from memory.
3755 Output_file::unmap()
3757 if (::munmap(this->base_
, this->file_size_
) < 0)
3758 gold_error(_("%s: munmap: %s"), this->name_
, strerror(errno
));
3762 // Close the output file.
3765 Output_file::close()
3767 // If the map isn't file-backed, we need to write it now.
3768 if (this->map_is_anonymous_
&& !this->is_temporary_
)
3770 size_t bytes_to_write
= this->file_size_
;
3772 while (bytes_to_write
> 0)
3774 ssize_t bytes_written
= ::write(this->o_
, this->base_
+ offset
,
3776 if (bytes_written
== 0)
3777 gold_error(_("%s: write: unexpected 0 return-value"), this->name_
);
3778 else if (bytes_written
< 0)
3779 gold_error(_("%s: write: %s"), this->name_
, strerror(errno
));
3782 bytes_to_write
-= bytes_written
;
3783 offset
+= bytes_written
;
3789 // We don't close stdout or stderr
3790 if (this->o_
!= STDOUT_FILENO
3791 && this->o_
!= STDERR_FILENO
3792 && !this->is_temporary_
)
3793 if (::close(this->o_
) < 0)
3794 gold_error(_("%s: close: %s"), this->name_
, strerror(errno
));
3798 // Instantiate the templates we need. We could use the configure
3799 // script to restrict this to only the ones for implemented targets.
3801 #ifdef HAVE_TARGET_32_LITTLE
3804 Output_section::add_input_section
<32, false>(
3805 Sized_relobj
<32, false>* object
,
3807 const char* secname
,
3808 const elfcpp::Shdr
<32, false>& shdr
,
3809 unsigned int reloc_shndx
,
3810 bool have_sections_script
);
3813 #ifdef HAVE_TARGET_32_BIG
3816 Output_section::add_input_section
<32, true>(
3817 Sized_relobj
<32, true>* object
,
3819 const char* secname
,
3820 const elfcpp::Shdr
<32, true>& shdr
,
3821 unsigned int reloc_shndx
,
3822 bool have_sections_script
);
3825 #ifdef HAVE_TARGET_64_LITTLE
3828 Output_section::add_input_section
<64, false>(
3829 Sized_relobj
<64, false>* object
,
3831 const char* secname
,
3832 const elfcpp::Shdr
<64, false>& shdr
,
3833 unsigned int reloc_shndx
,
3834 bool have_sections_script
);
3837 #ifdef HAVE_TARGET_64_BIG
3840 Output_section::add_input_section
<64, true>(
3841 Sized_relobj
<64, true>* object
,
3843 const char* secname
,
3844 const elfcpp::Shdr
<64, true>& shdr
,
3845 unsigned int reloc_shndx
,
3846 bool have_sections_script
);
3849 #ifdef HAVE_TARGET_32_LITTLE
3851 class Output_reloc
<elfcpp::SHT_REL
, false, 32, false>;
3854 #ifdef HAVE_TARGET_32_BIG
3856 class Output_reloc
<elfcpp::SHT_REL
, false, 32, true>;
3859 #ifdef HAVE_TARGET_64_LITTLE
3861 class Output_reloc
<elfcpp::SHT_REL
, false, 64, false>;
3864 #ifdef HAVE_TARGET_64_BIG
3866 class Output_reloc
<elfcpp::SHT_REL
, false, 64, true>;
3869 #ifdef HAVE_TARGET_32_LITTLE
3871 class Output_reloc
<elfcpp::SHT_REL
, true, 32, false>;
3874 #ifdef HAVE_TARGET_32_BIG
3876 class Output_reloc
<elfcpp::SHT_REL
, true, 32, true>;
3879 #ifdef HAVE_TARGET_64_LITTLE
3881 class Output_reloc
<elfcpp::SHT_REL
, true, 64, false>;
3884 #ifdef HAVE_TARGET_64_BIG
3886 class Output_reloc
<elfcpp::SHT_REL
, true, 64, true>;
3889 #ifdef HAVE_TARGET_32_LITTLE
3891 class Output_reloc
<elfcpp::SHT_RELA
, false, 32, false>;
3894 #ifdef HAVE_TARGET_32_BIG
3896 class Output_reloc
<elfcpp::SHT_RELA
, false, 32, true>;
3899 #ifdef HAVE_TARGET_64_LITTLE
3901 class Output_reloc
<elfcpp::SHT_RELA
, false, 64, false>;
3904 #ifdef HAVE_TARGET_64_BIG
3906 class Output_reloc
<elfcpp::SHT_RELA
, false, 64, true>;
3909 #ifdef HAVE_TARGET_32_LITTLE
3911 class Output_reloc
<elfcpp::SHT_RELA
, true, 32, false>;
3914 #ifdef HAVE_TARGET_32_BIG
3916 class Output_reloc
<elfcpp::SHT_RELA
, true, 32, true>;
3919 #ifdef HAVE_TARGET_64_LITTLE
3921 class Output_reloc
<elfcpp::SHT_RELA
, true, 64, false>;
3924 #ifdef HAVE_TARGET_64_BIG
3926 class Output_reloc
<elfcpp::SHT_RELA
, true, 64, true>;
3929 #ifdef HAVE_TARGET_32_LITTLE
3931 class Output_data_reloc
<elfcpp::SHT_REL
, false, 32, false>;
3934 #ifdef HAVE_TARGET_32_BIG
3936 class Output_data_reloc
<elfcpp::SHT_REL
, false, 32, true>;
3939 #ifdef HAVE_TARGET_64_LITTLE
3941 class Output_data_reloc
<elfcpp::SHT_REL
, false, 64, false>;
3944 #ifdef HAVE_TARGET_64_BIG
3946 class Output_data_reloc
<elfcpp::SHT_REL
, false, 64, true>;
3949 #ifdef HAVE_TARGET_32_LITTLE
3951 class Output_data_reloc
<elfcpp::SHT_REL
, true, 32, false>;
3954 #ifdef HAVE_TARGET_32_BIG
3956 class Output_data_reloc
<elfcpp::SHT_REL
, true, 32, true>;
3959 #ifdef HAVE_TARGET_64_LITTLE
3961 class Output_data_reloc
<elfcpp::SHT_REL
, true, 64, false>;
3964 #ifdef HAVE_TARGET_64_BIG
3966 class Output_data_reloc
<elfcpp::SHT_REL
, true, 64, true>;
3969 #ifdef HAVE_TARGET_32_LITTLE
3971 class Output_data_reloc
<elfcpp::SHT_RELA
, false, 32, false>;
3974 #ifdef HAVE_TARGET_32_BIG
3976 class Output_data_reloc
<elfcpp::SHT_RELA
, false, 32, true>;
3979 #ifdef HAVE_TARGET_64_LITTLE
3981 class Output_data_reloc
<elfcpp::SHT_RELA
, false, 64, false>;
3984 #ifdef HAVE_TARGET_64_BIG
3986 class Output_data_reloc
<elfcpp::SHT_RELA
, false, 64, true>;
3989 #ifdef HAVE_TARGET_32_LITTLE
3991 class Output_data_reloc
<elfcpp::SHT_RELA
, true, 32, false>;
3994 #ifdef HAVE_TARGET_32_BIG
3996 class Output_data_reloc
<elfcpp::SHT_RELA
, true, 32, true>;
3999 #ifdef HAVE_TARGET_64_LITTLE
4001 class Output_data_reloc
<elfcpp::SHT_RELA
, true, 64, false>;
4004 #ifdef HAVE_TARGET_64_BIG
4006 class Output_data_reloc
<elfcpp::SHT_RELA
, true, 64, true>;
4009 #ifdef HAVE_TARGET_32_LITTLE
4011 class Output_relocatable_relocs
<elfcpp::SHT_REL
, 32, false>;
4014 #ifdef HAVE_TARGET_32_BIG
4016 class Output_relocatable_relocs
<elfcpp::SHT_REL
, 32, true>;
4019 #ifdef HAVE_TARGET_64_LITTLE
4021 class Output_relocatable_relocs
<elfcpp::SHT_REL
, 64, false>;
4024 #ifdef HAVE_TARGET_64_BIG
4026 class Output_relocatable_relocs
<elfcpp::SHT_REL
, 64, true>;
4029 #ifdef HAVE_TARGET_32_LITTLE
4031 class Output_relocatable_relocs
<elfcpp::SHT_RELA
, 32, false>;
4034 #ifdef HAVE_TARGET_32_BIG
4036 class Output_relocatable_relocs
<elfcpp::SHT_RELA
, 32, true>;
4039 #ifdef HAVE_TARGET_64_LITTLE
4041 class Output_relocatable_relocs
<elfcpp::SHT_RELA
, 64, false>;
4044 #ifdef HAVE_TARGET_64_BIG
4046 class Output_relocatable_relocs
<elfcpp::SHT_RELA
, 64, true>;
4049 #ifdef HAVE_TARGET_32_LITTLE
4051 class Output_data_group
<32, false>;
4054 #ifdef HAVE_TARGET_32_BIG
4056 class Output_data_group
<32, true>;
4059 #ifdef HAVE_TARGET_64_LITTLE
4061 class Output_data_group
<64, false>;
4064 #ifdef HAVE_TARGET_64_BIG
4066 class Output_data_group
<64, true>;
4069 #ifdef HAVE_TARGET_32_LITTLE
4071 class Output_data_got
<32, false>;
4074 #ifdef HAVE_TARGET_32_BIG
4076 class Output_data_got
<32, true>;
4079 #ifdef HAVE_TARGET_64_LITTLE
4081 class Output_data_got
<64, false>;
4084 #ifdef HAVE_TARGET_64_BIG
4086 class Output_data_got
<64, true>;
4089 } // End namespace gold.