1 // output.cc -- manage the output file for gold
3 // Copyright (C) 2006-2015 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 #ifdef HAVE_SYS_MMAN_H
37 #include "libiberty.h"
40 #include "parameters.h"
45 #include "descriptors.h"
49 // For systems without mmap support.
51 # define mmap gold_mmap
52 # define munmap gold_munmap
53 # define mremap gold_mremap
55 # define MAP_FAILED (reinterpret_cast<void*>(-1))
64 # define MAP_PRIVATE 0
66 # ifndef MAP_ANONYMOUS
67 # define MAP_ANONYMOUS 0
74 # define ENOSYS EINVAL
78 gold_mmap(void *, size_t, int, int, int, off_t
)
85 gold_munmap(void *, size_t)
92 gold_mremap(void *, size_t, size_t, int)
100 #if defined(HAVE_MMAP) && !defined(HAVE_MREMAP)
101 # define mremap gold_mremap
102 extern "C" void *gold_mremap(void *, size_t, size_t, int);
105 // Some BSD systems still use MAP_ANON instead of MAP_ANONYMOUS
106 #ifndef MAP_ANONYMOUS
107 # define MAP_ANONYMOUS MAP_ANON
110 #ifndef MREMAP_MAYMOVE
111 # define MREMAP_MAYMOVE 1
114 // Mingw does not have S_ISLNK.
116 # define S_ISLNK(mode) 0
122 // A wrapper around posix_fallocate. If we don't have posix_fallocate,
123 // or the --no-posix-fallocate option is set, we try the fallocate
124 // system call directly. If that fails, we use ftruncate to set
125 // the file size and hope that there is enough disk space.
128 gold_fallocate(int o
, off_t offset
, off_t len
)
130 #ifdef HAVE_POSIX_FALLOCATE
131 if (parameters
->options().posix_fallocate())
132 return ::posix_fallocate(o
, offset
, len
);
133 #endif // defined(HAVE_POSIX_FALLOCATE)
134 #ifdef HAVE_FALLOCATE
135 if (::fallocate(o
, 0, offset
, len
) == 0)
137 #endif // defined(HAVE_FALLOCATE)
138 if (::ftruncate(o
, offset
+ len
) < 0)
143 // Output_data variables.
145 bool Output_data::allocated_sizes_are_fixed
;
147 // Output_data methods.
149 Output_data::~Output_data()
153 // Return the default alignment for the target size.
156 Output_data::default_alignment()
158 return Output_data::default_alignment_for_size(
159 parameters
->target().get_size());
162 // Return the default alignment for a size--32 or 64.
165 Output_data::default_alignment_for_size(int size
)
175 // Output_section_header methods. This currently assumes that the
176 // segment and section lists are complete at construction time.
178 Output_section_headers::Output_section_headers(
179 const Layout
* layout
,
180 const Layout::Segment_list
* segment_list
,
181 const Layout::Section_list
* section_list
,
182 const Layout::Section_list
* unattached_section_list
,
183 const Stringpool
* secnamepool
,
184 const Output_section
* shstrtab_section
)
186 segment_list_(segment_list
),
187 section_list_(section_list
),
188 unattached_section_list_(unattached_section_list
),
189 secnamepool_(secnamepool
),
190 shstrtab_section_(shstrtab_section
)
194 // Compute the current data size.
197 Output_section_headers::do_size() const
199 // Count all the sections. Start with 1 for the null section.
201 if (!parameters
->options().relocatable())
203 for (Layout::Segment_list::const_iterator p
=
204 this->segment_list_
->begin();
205 p
!= this->segment_list_
->end();
207 if ((*p
)->type() == elfcpp::PT_LOAD
)
208 count
+= (*p
)->output_section_count();
212 for (Layout::Section_list::const_iterator p
=
213 this->section_list_
->begin();
214 p
!= this->section_list_
->end();
216 if (((*p
)->flags() & elfcpp::SHF_ALLOC
) != 0)
219 count
+= this->unattached_section_list_
->size();
221 const int size
= parameters
->target().get_size();
224 shdr_size
= elfcpp::Elf_sizes
<32>::shdr_size
;
226 shdr_size
= elfcpp::Elf_sizes
<64>::shdr_size
;
230 return count
* shdr_size
;
233 // Write out the section headers.
236 Output_section_headers::do_write(Output_file
* of
)
238 switch (parameters
->size_and_endianness())
240 #ifdef HAVE_TARGET_32_LITTLE
241 case Parameters::TARGET_32_LITTLE
:
242 this->do_sized_write
<32, false>(of
);
245 #ifdef HAVE_TARGET_32_BIG
246 case Parameters::TARGET_32_BIG
:
247 this->do_sized_write
<32, true>(of
);
250 #ifdef HAVE_TARGET_64_LITTLE
251 case Parameters::TARGET_64_LITTLE
:
252 this->do_sized_write
<64, false>(of
);
255 #ifdef HAVE_TARGET_64_BIG
256 case Parameters::TARGET_64_BIG
:
257 this->do_sized_write
<64, true>(of
);
265 template<int size
, bool big_endian
>
267 Output_section_headers::do_sized_write(Output_file
* of
)
269 off_t all_shdrs_size
= this->data_size();
270 unsigned char* view
= of
->get_output_view(this->offset(), all_shdrs_size
);
272 const int shdr_size
= elfcpp::Elf_sizes
<size
>::shdr_size
;
273 unsigned char* v
= view
;
276 typename
elfcpp::Shdr_write
<size
, big_endian
> oshdr(v
);
277 oshdr
.put_sh_name(0);
278 oshdr
.put_sh_type(elfcpp::SHT_NULL
);
279 oshdr
.put_sh_flags(0);
280 oshdr
.put_sh_addr(0);
281 oshdr
.put_sh_offset(0);
283 size_t section_count
= (this->data_size()
284 / elfcpp::Elf_sizes
<size
>::shdr_size
);
285 if (section_count
< elfcpp::SHN_LORESERVE
)
286 oshdr
.put_sh_size(0);
288 oshdr
.put_sh_size(section_count
);
290 unsigned int shstrndx
= this->shstrtab_section_
->out_shndx();
291 if (shstrndx
< elfcpp::SHN_LORESERVE
)
292 oshdr
.put_sh_link(0);
294 oshdr
.put_sh_link(shstrndx
);
296 size_t segment_count
= this->segment_list_
->size();
297 oshdr
.put_sh_info(segment_count
>= elfcpp::PN_XNUM
? segment_count
: 0);
299 oshdr
.put_sh_addralign(0);
300 oshdr
.put_sh_entsize(0);
305 unsigned int shndx
= 1;
306 if (!parameters
->options().relocatable())
308 for (Layout::Segment_list::const_iterator p
=
309 this->segment_list_
->begin();
310 p
!= this->segment_list_
->end();
312 v
= (*p
)->write_section_headers
<size
, big_endian
>(this->layout_
,
319 for (Layout::Section_list::const_iterator p
=
320 this->section_list_
->begin();
321 p
!= this->section_list_
->end();
324 // We do unallocated sections below, except that group
325 // sections have to come first.
326 if (((*p
)->flags() & elfcpp::SHF_ALLOC
) == 0
327 && (*p
)->type() != elfcpp::SHT_GROUP
)
329 gold_assert(shndx
== (*p
)->out_shndx());
330 elfcpp::Shdr_write
<size
, big_endian
> oshdr(v
);
331 (*p
)->write_header(this->layout_
, this->secnamepool_
, &oshdr
);
337 for (Layout::Section_list::const_iterator p
=
338 this->unattached_section_list_
->begin();
339 p
!= this->unattached_section_list_
->end();
342 // For a relocatable link, we did unallocated group sections
343 // above, since they have to come first.
344 if ((*p
)->type() == elfcpp::SHT_GROUP
345 && parameters
->options().relocatable())
347 gold_assert(shndx
== (*p
)->out_shndx());
348 elfcpp::Shdr_write
<size
, big_endian
> oshdr(v
);
349 (*p
)->write_header(this->layout_
, this->secnamepool_
, &oshdr
);
354 of
->write_output_view(this->offset(), all_shdrs_size
, view
);
357 // Output_segment_header methods.
359 Output_segment_headers::Output_segment_headers(
360 const Layout::Segment_list
& segment_list
)
361 : segment_list_(segment_list
)
363 this->set_current_data_size_for_child(this->do_size());
367 Output_segment_headers::do_write(Output_file
* of
)
369 switch (parameters
->size_and_endianness())
371 #ifdef HAVE_TARGET_32_LITTLE
372 case Parameters::TARGET_32_LITTLE
:
373 this->do_sized_write
<32, false>(of
);
376 #ifdef HAVE_TARGET_32_BIG
377 case Parameters::TARGET_32_BIG
:
378 this->do_sized_write
<32, true>(of
);
381 #ifdef HAVE_TARGET_64_LITTLE
382 case Parameters::TARGET_64_LITTLE
:
383 this->do_sized_write
<64, false>(of
);
386 #ifdef HAVE_TARGET_64_BIG
387 case Parameters::TARGET_64_BIG
:
388 this->do_sized_write
<64, true>(of
);
396 template<int size
, bool big_endian
>
398 Output_segment_headers::do_sized_write(Output_file
* of
)
400 const int phdr_size
= elfcpp::Elf_sizes
<size
>::phdr_size
;
401 off_t all_phdrs_size
= this->segment_list_
.size() * phdr_size
;
402 gold_assert(all_phdrs_size
== this->data_size());
403 unsigned char* view
= of
->get_output_view(this->offset(),
405 unsigned char* v
= view
;
406 for (Layout::Segment_list::const_iterator p
= this->segment_list_
.begin();
407 p
!= this->segment_list_
.end();
410 elfcpp::Phdr_write
<size
, big_endian
> ophdr(v
);
411 (*p
)->write_header(&ophdr
);
415 gold_assert(v
- view
== all_phdrs_size
);
417 of
->write_output_view(this->offset(), all_phdrs_size
, view
);
421 Output_segment_headers::do_size() const
423 const int size
= parameters
->target().get_size();
426 phdr_size
= elfcpp::Elf_sizes
<32>::phdr_size
;
428 phdr_size
= elfcpp::Elf_sizes
<64>::phdr_size
;
432 return this->segment_list_
.size() * phdr_size
;
435 // Output_file_header methods.
437 Output_file_header::Output_file_header(Target
* target
,
438 const Symbol_table
* symtab
,
439 const Output_segment_headers
* osh
)
442 segment_header_(osh
),
443 section_header_(NULL
),
446 this->set_data_size(this->do_size());
449 // Set the section table information for a file header.
452 Output_file_header::set_section_info(const Output_section_headers
* shdrs
,
453 const Output_section
* shstrtab
)
455 this->section_header_
= shdrs
;
456 this->shstrtab_
= shstrtab
;
459 // Write out the file header.
462 Output_file_header::do_write(Output_file
* of
)
464 gold_assert(this->offset() == 0);
466 switch (parameters
->size_and_endianness())
468 #ifdef HAVE_TARGET_32_LITTLE
469 case Parameters::TARGET_32_LITTLE
:
470 this->do_sized_write
<32, false>(of
);
473 #ifdef HAVE_TARGET_32_BIG
474 case Parameters::TARGET_32_BIG
:
475 this->do_sized_write
<32, true>(of
);
478 #ifdef HAVE_TARGET_64_LITTLE
479 case Parameters::TARGET_64_LITTLE
:
480 this->do_sized_write
<64, false>(of
);
483 #ifdef HAVE_TARGET_64_BIG
484 case Parameters::TARGET_64_BIG
:
485 this->do_sized_write
<64, true>(of
);
493 // Write out the file header with appropriate size and endianness.
495 template<int size
, bool big_endian
>
497 Output_file_header::do_sized_write(Output_file
* of
)
499 gold_assert(this->offset() == 0);
501 int ehdr_size
= elfcpp::Elf_sizes
<size
>::ehdr_size
;
502 unsigned char* view
= of
->get_output_view(0, ehdr_size
);
503 elfcpp::Ehdr_write
<size
, big_endian
> oehdr(view
);
505 unsigned char e_ident
[elfcpp::EI_NIDENT
];
506 memset(e_ident
, 0, elfcpp::EI_NIDENT
);
507 e_ident
[elfcpp::EI_MAG0
] = elfcpp::ELFMAG0
;
508 e_ident
[elfcpp::EI_MAG1
] = elfcpp::ELFMAG1
;
509 e_ident
[elfcpp::EI_MAG2
] = elfcpp::ELFMAG2
;
510 e_ident
[elfcpp::EI_MAG3
] = elfcpp::ELFMAG3
;
512 e_ident
[elfcpp::EI_CLASS
] = elfcpp::ELFCLASS32
;
514 e_ident
[elfcpp::EI_CLASS
] = elfcpp::ELFCLASS64
;
517 e_ident
[elfcpp::EI_DATA
] = (big_endian
518 ? elfcpp::ELFDATA2MSB
519 : elfcpp::ELFDATA2LSB
);
520 e_ident
[elfcpp::EI_VERSION
] = elfcpp::EV_CURRENT
;
521 oehdr
.put_e_ident(e_ident
);
524 if (parameters
->options().relocatable())
525 e_type
= elfcpp::ET_REL
;
526 else if (parameters
->options().output_is_position_independent())
527 e_type
= elfcpp::ET_DYN
;
529 e_type
= elfcpp::ET_EXEC
;
530 oehdr
.put_e_type(e_type
);
532 oehdr
.put_e_machine(this->target_
->machine_code());
533 oehdr
.put_e_version(elfcpp::EV_CURRENT
);
535 oehdr
.put_e_entry(this->entry
<size
>());
537 if (this->segment_header_
== NULL
)
538 oehdr
.put_e_phoff(0);
540 oehdr
.put_e_phoff(this->segment_header_
->offset());
542 oehdr
.put_e_shoff(this->section_header_
->offset());
543 oehdr
.put_e_flags(this->target_
->processor_specific_flags());
544 oehdr
.put_e_ehsize(elfcpp::Elf_sizes
<size
>::ehdr_size
);
546 if (this->segment_header_
== NULL
)
548 oehdr
.put_e_phentsize(0);
549 oehdr
.put_e_phnum(0);
553 oehdr
.put_e_phentsize(elfcpp::Elf_sizes
<size
>::phdr_size
);
554 size_t phnum
= (this->segment_header_
->data_size()
555 / elfcpp::Elf_sizes
<size
>::phdr_size
);
556 if (phnum
> elfcpp::PN_XNUM
)
557 phnum
= elfcpp::PN_XNUM
;
558 oehdr
.put_e_phnum(phnum
);
561 oehdr
.put_e_shentsize(elfcpp::Elf_sizes
<size
>::shdr_size
);
562 size_t section_count
= (this->section_header_
->data_size()
563 / elfcpp::Elf_sizes
<size
>::shdr_size
);
565 if (section_count
< elfcpp::SHN_LORESERVE
)
566 oehdr
.put_e_shnum(this->section_header_
->data_size()
567 / elfcpp::Elf_sizes
<size
>::shdr_size
);
569 oehdr
.put_e_shnum(0);
571 unsigned int shstrndx
= this->shstrtab_
->out_shndx();
572 if (shstrndx
< elfcpp::SHN_LORESERVE
)
573 oehdr
.put_e_shstrndx(this->shstrtab_
->out_shndx());
575 oehdr
.put_e_shstrndx(elfcpp::SHN_XINDEX
);
577 // Let the target adjust the ELF header, e.g., to set EI_OSABI in
578 // the e_ident field.
579 this->target_
->adjust_elf_header(view
, ehdr_size
);
581 of
->write_output_view(0, ehdr_size
, view
);
584 // Return the value to use for the entry address.
587 typename
elfcpp::Elf_types
<size
>::Elf_Addr
588 Output_file_header::entry()
590 const bool should_issue_warning
= (parameters
->options().entry() != NULL
591 && !parameters
->options().relocatable()
592 && !parameters
->options().shared());
593 const char* entry
= parameters
->entry();
594 Symbol
* sym
= this->symtab_
->lookup(entry
);
596 typename Sized_symbol
<size
>::Value_type v
;
599 Sized_symbol
<size
>* ssym
;
600 ssym
= this->symtab_
->get_sized_symbol
<size
>(sym
);
601 if (!ssym
->is_defined() && should_issue_warning
)
602 gold_warning("entry symbol '%s' exists but is not defined", entry
);
607 // We couldn't find the entry symbol. See if we can parse it as
608 // a number. This supports, e.g., -e 0x1000.
610 v
= strtoull(entry
, &endptr
, 0);
613 if (should_issue_warning
)
614 gold_warning("cannot find entry symbol '%s'", entry
);
622 // Compute the current data size.
625 Output_file_header::do_size() const
627 const int size
= parameters
->target().get_size();
629 return elfcpp::Elf_sizes
<32>::ehdr_size
;
631 return elfcpp::Elf_sizes
<64>::ehdr_size
;
636 // Output_data_const methods.
639 Output_data_const::do_write(Output_file
* of
)
641 of
->write(this->offset(), this->data_
.data(), this->data_
.size());
644 // Output_data_const_buffer methods.
647 Output_data_const_buffer::do_write(Output_file
* of
)
649 of
->write(this->offset(), this->p_
, this->data_size());
652 // Output_section_data methods.
654 // Record the output section, and set the entry size and such.
657 Output_section_data::set_output_section(Output_section
* os
)
659 gold_assert(this->output_section_
== NULL
);
660 this->output_section_
= os
;
661 this->do_adjust_output_section(os
);
664 // Return the section index of the output section.
667 Output_section_data::do_out_shndx() const
669 gold_assert(this->output_section_
!= NULL
);
670 return this->output_section_
->out_shndx();
673 // Set the alignment, which means we may need to update the alignment
674 // of the output section.
677 Output_section_data::set_addralign(uint64_t addralign
)
679 this->addralign_
= addralign
;
680 if (this->output_section_
!= NULL
681 && this->output_section_
->addralign() < addralign
)
682 this->output_section_
->set_addralign(addralign
);
685 // Output_data_strtab methods.
687 // Set the final data size.
690 Output_data_strtab::set_final_data_size()
692 this->strtab_
->set_string_offsets();
693 this->set_data_size(this->strtab_
->get_strtab_size());
696 // Write out a string table.
699 Output_data_strtab::do_write(Output_file
* of
)
701 this->strtab_
->write(of
, this->offset());
704 // Output_reloc methods.
706 // A reloc against a global symbol.
708 template<bool dynamic
, int size
, bool big_endian
>
709 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::Output_reloc(
717 : address_(address
), local_sym_index_(GSYM_CODE
), type_(type
),
718 is_relative_(is_relative
), is_symbolless_(is_symbolless
),
719 is_section_symbol_(false), use_plt_offset_(use_plt_offset
), shndx_(INVALID_CODE
)
721 // this->type_ is a bitfield; make sure TYPE fits.
722 gold_assert(this->type_
== type
);
723 this->u1_
.gsym
= gsym
;
726 this->set_needs_dynsym_index();
729 template<bool dynamic
, int size
, bool big_endian
>
730 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::Output_reloc(
733 Sized_relobj
<size
, big_endian
>* relobj
,
739 : address_(address
), local_sym_index_(GSYM_CODE
), type_(type
),
740 is_relative_(is_relative
), is_symbolless_(is_symbolless
),
741 is_section_symbol_(false), use_plt_offset_(use_plt_offset
), shndx_(shndx
)
743 gold_assert(shndx
!= INVALID_CODE
);
744 // this->type_ is a bitfield; make sure TYPE fits.
745 gold_assert(this->type_
== type
);
746 this->u1_
.gsym
= gsym
;
747 this->u2_
.relobj
= relobj
;
749 this->set_needs_dynsym_index();
752 // A reloc against a local symbol.
754 template<bool dynamic
, int size
, bool big_endian
>
755 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::Output_reloc(
756 Sized_relobj
<size
, big_endian
>* relobj
,
757 unsigned int local_sym_index
,
763 bool is_section_symbol
,
765 : address_(address
), local_sym_index_(local_sym_index
), type_(type
),
766 is_relative_(is_relative
), is_symbolless_(is_symbolless
),
767 is_section_symbol_(is_section_symbol
), use_plt_offset_(use_plt_offset
),
770 gold_assert(local_sym_index
!= GSYM_CODE
771 && local_sym_index
!= INVALID_CODE
);
772 // this->type_ is a bitfield; make sure TYPE fits.
773 gold_assert(this->type_
== type
);
774 this->u1_
.relobj
= relobj
;
777 this->set_needs_dynsym_index();
780 template<bool dynamic
, int size
, bool big_endian
>
781 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::Output_reloc(
782 Sized_relobj
<size
, big_endian
>* relobj
,
783 unsigned int local_sym_index
,
789 bool is_section_symbol
,
791 : address_(address
), local_sym_index_(local_sym_index
), type_(type
),
792 is_relative_(is_relative
), is_symbolless_(is_symbolless
),
793 is_section_symbol_(is_section_symbol
), use_plt_offset_(use_plt_offset
),
796 gold_assert(local_sym_index
!= GSYM_CODE
797 && local_sym_index
!= INVALID_CODE
);
798 gold_assert(shndx
!= INVALID_CODE
);
799 // this->type_ is a bitfield; make sure TYPE fits.
800 gold_assert(this->type_
== type
);
801 this->u1_
.relobj
= relobj
;
802 this->u2_
.relobj
= relobj
;
804 this->set_needs_dynsym_index();
807 // A reloc against the STT_SECTION symbol of an output section.
809 template<bool dynamic
, int size
, bool big_endian
>
810 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::Output_reloc(
816 : address_(address
), local_sym_index_(SECTION_CODE
), type_(type
),
817 is_relative_(is_relative
), is_symbolless_(is_relative
),
818 is_section_symbol_(true), use_plt_offset_(false), shndx_(INVALID_CODE
)
820 // this->type_ is a bitfield; make sure TYPE fits.
821 gold_assert(this->type_
== type
);
825 this->set_needs_dynsym_index();
827 os
->set_needs_symtab_index();
830 template<bool dynamic
, int size
, bool big_endian
>
831 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::Output_reloc(
834 Sized_relobj
<size
, big_endian
>* relobj
,
838 : address_(address
), local_sym_index_(SECTION_CODE
), type_(type
),
839 is_relative_(is_relative
), is_symbolless_(is_relative
),
840 is_section_symbol_(true), use_plt_offset_(false), shndx_(shndx
)
842 gold_assert(shndx
!= INVALID_CODE
);
843 // this->type_ is a bitfield; make sure TYPE fits.
844 gold_assert(this->type_
== type
);
846 this->u2_
.relobj
= relobj
;
848 this->set_needs_dynsym_index();
850 os
->set_needs_symtab_index();
853 // An absolute or relative relocation.
855 template<bool dynamic
, int size
, bool big_endian
>
856 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::Output_reloc(
861 : address_(address
), local_sym_index_(0), type_(type
),
862 is_relative_(is_relative
), is_symbolless_(false),
863 is_section_symbol_(false), use_plt_offset_(false), shndx_(INVALID_CODE
)
865 // this->type_ is a bitfield; make sure TYPE fits.
866 gold_assert(this->type_
== type
);
867 this->u1_
.relobj
= NULL
;
871 template<bool dynamic
, int size
, bool big_endian
>
872 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::Output_reloc(
874 Sized_relobj
<size
, big_endian
>* relobj
,
878 : address_(address
), local_sym_index_(0), type_(type
),
879 is_relative_(is_relative
), is_symbolless_(false),
880 is_section_symbol_(false), use_plt_offset_(false), shndx_(shndx
)
882 gold_assert(shndx
!= INVALID_CODE
);
883 // this->type_ is a bitfield; make sure TYPE fits.
884 gold_assert(this->type_
== type
);
885 this->u1_
.relobj
= NULL
;
886 this->u2_
.relobj
= relobj
;
889 // A target specific relocation.
891 template<bool dynamic
, int size
, bool big_endian
>
892 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::Output_reloc(
897 : address_(address
), local_sym_index_(TARGET_CODE
), type_(type
),
898 is_relative_(false), is_symbolless_(false),
899 is_section_symbol_(false), use_plt_offset_(false), shndx_(INVALID_CODE
)
901 // this->type_ is a bitfield; make sure TYPE fits.
902 gold_assert(this->type_
== type
);
907 template<bool dynamic
, int size
, bool big_endian
>
908 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::Output_reloc(
911 Sized_relobj
<size
, big_endian
>* relobj
,
914 : address_(address
), local_sym_index_(TARGET_CODE
), type_(type
),
915 is_relative_(false), is_symbolless_(false),
916 is_section_symbol_(false), use_plt_offset_(false), shndx_(shndx
)
918 gold_assert(shndx
!= INVALID_CODE
);
919 // this->type_ is a bitfield; make sure TYPE fits.
920 gold_assert(this->type_
== type
);
922 this->u2_
.relobj
= relobj
;
925 // Record that we need a dynamic symbol index for this relocation.
927 template<bool dynamic
, int size
, bool big_endian
>
929 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::
930 set_needs_dynsym_index()
932 if (this->is_symbolless_
)
934 switch (this->local_sym_index_
)
940 this->u1_
.gsym
->set_needs_dynsym_entry();
944 this->u1_
.os
->set_needs_dynsym_index();
948 // The target must take care of this if necessary.
956 const unsigned int lsi
= this->local_sym_index_
;
957 Sized_relobj_file
<size
, big_endian
>* relobj
=
958 this->u1_
.relobj
->sized_relobj();
959 gold_assert(relobj
!= NULL
);
960 if (!this->is_section_symbol_
)
961 relobj
->set_needs_output_dynsym_entry(lsi
);
963 relobj
->output_section(lsi
)->set_needs_dynsym_index();
969 // Get the symbol index of a relocation.
971 template<bool dynamic
, int size
, bool big_endian
>
973 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::get_symbol_index()
977 if (this->is_symbolless_
)
979 switch (this->local_sym_index_
)
985 if (this->u1_
.gsym
== NULL
)
988 index
= this->u1_
.gsym
->dynsym_index();
990 index
= this->u1_
.gsym
->symtab_index();
995 index
= this->u1_
.os
->dynsym_index();
997 index
= this->u1_
.os
->symtab_index();
1001 index
= parameters
->target().reloc_symbol_index(this->u1_
.arg
,
1006 // Relocations without symbols use a symbol index of 0.
1012 const unsigned int lsi
= this->local_sym_index_
;
1013 Sized_relobj_file
<size
, big_endian
>* relobj
=
1014 this->u1_
.relobj
->sized_relobj();
1015 gold_assert(relobj
!= NULL
);
1016 if (!this->is_section_symbol_
)
1019 index
= relobj
->dynsym_index(lsi
);
1021 index
= relobj
->symtab_index(lsi
);
1025 Output_section
* os
= relobj
->output_section(lsi
);
1026 gold_assert(os
!= NULL
);
1028 index
= os
->dynsym_index();
1030 index
= os
->symtab_index();
1035 gold_assert(index
!= -1U);
1039 // For a local section symbol, get the address of the offset ADDEND
1040 // within the input section.
1042 template<bool dynamic
, int size
, bool big_endian
>
1043 typename
elfcpp::Elf_types
<size
>::Elf_Addr
1044 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::
1045 local_section_offset(Addend addend
) const
1047 gold_assert(this->local_sym_index_
!= GSYM_CODE
1048 && this->local_sym_index_
!= SECTION_CODE
1049 && this->local_sym_index_
!= TARGET_CODE
1050 && this->local_sym_index_
!= INVALID_CODE
1051 && this->local_sym_index_
!= 0
1052 && this->is_section_symbol_
);
1053 const unsigned int lsi
= this->local_sym_index_
;
1054 Output_section
* os
= this->u1_
.relobj
->output_section(lsi
);
1055 gold_assert(os
!= NULL
);
1056 Address offset
= this->u1_
.relobj
->get_output_section_offset(lsi
);
1057 if (offset
!= invalid_address
)
1058 return offset
+ addend
;
1059 // This is a merge section.
1060 Sized_relobj_file
<size
, big_endian
>* relobj
=
1061 this->u1_
.relobj
->sized_relobj();
1062 gold_assert(relobj
!= NULL
);
1063 offset
= os
->output_address(relobj
, lsi
, addend
);
1064 gold_assert(offset
!= invalid_address
);
1068 // Get the output address of a relocation.
1070 template<bool dynamic
, int size
, bool big_endian
>
1071 typename
elfcpp::Elf_types
<size
>::Elf_Addr
1072 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::get_address() const
1074 Address address
= this->address_
;
1075 if (this->shndx_
!= INVALID_CODE
)
1077 Output_section
* os
= this->u2_
.relobj
->output_section(this->shndx_
);
1078 gold_assert(os
!= NULL
);
1079 Address off
= this->u2_
.relobj
->get_output_section_offset(this->shndx_
);
1080 if (off
!= invalid_address
)
1081 address
+= os
->address() + off
;
1084 Sized_relobj_file
<size
, big_endian
>* relobj
=
1085 this->u2_
.relobj
->sized_relobj();
1086 gold_assert(relobj
!= NULL
);
1087 address
= os
->output_address(relobj
, this->shndx_
, address
);
1088 gold_assert(address
!= invalid_address
);
1091 else if (this->u2_
.od
!= NULL
)
1092 address
+= this->u2_
.od
->address();
1096 // Write out the offset and info fields of a Rel or Rela relocation
1099 template<bool dynamic
, int size
, bool big_endian
>
1100 template<typename Write_rel
>
1102 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::write_rel(
1103 Write_rel
* wr
) const
1105 wr
->put_r_offset(this->get_address());
1106 unsigned int sym_index
= this->get_symbol_index();
1107 wr
->put_r_info(elfcpp::elf_r_info
<size
>(sym_index
, this->type_
));
1110 // Write out a Rel relocation.
1112 template<bool dynamic
, int size
, bool big_endian
>
1114 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::write(
1115 unsigned char* pov
) const
1117 elfcpp::Rel_write
<size
, big_endian
> orel(pov
);
1118 this->write_rel(&orel
);
1121 // Get the value of the symbol referred to by a Rel relocation.
1123 template<bool dynamic
, int size
, bool big_endian
>
1124 typename
elfcpp::Elf_types
<size
>::Elf_Addr
1125 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::symbol_value(
1126 Addend addend
) const
1128 if (this->local_sym_index_
== GSYM_CODE
)
1130 const Sized_symbol
<size
>* sym
;
1131 sym
= static_cast<const Sized_symbol
<size
>*>(this->u1_
.gsym
);
1132 if (this->use_plt_offset_
&& sym
->has_plt_offset())
1133 return parameters
->target().plt_address_for_global(sym
);
1135 return sym
->value() + addend
;
1137 if (this->local_sym_index_
== SECTION_CODE
)
1139 gold_assert(!this->use_plt_offset_
);
1140 return this->u1_
.os
->address() + addend
;
1142 gold_assert(this->local_sym_index_
!= TARGET_CODE
1143 && this->local_sym_index_
!= INVALID_CODE
1144 && this->local_sym_index_
!= 0
1145 && !this->is_section_symbol_
);
1146 const unsigned int lsi
= this->local_sym_index_
;
1147 Sized_relobj_file
<size
, big_endian
>* relobj
=
1148 this->u1_
.relobj
->sized_relobj();
1149 gold_assert(relobj
!= NULL
);
1150 if (this->use_plt_offset_
)
1151 return parameters
->target().plt_address_for_local(relobj
, lsi
);
1152 const Symbol_value
<size
>* symval
= relobj
->local_symbol(lsi
);
1153 return symval
->value(relobj
, addend
);
1156 // Reloc comparison. This function sorts the dynamic relocs for the
1157 // benefit of the dynamic linker. First we sort all relative relocs
1158 // to the front. Among relative relocs, we sort by output address.
1159 // Among non-relative relocs, we sort by symbol index, then by output
1162 template<bool dynamic
, int size
, bool big_endian
>
1164 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::
1165 compare(const Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>& r2
)
1168 if (this->is_relative_
)
1170 if (!r2
.is_relative_
)
1172 // Otherwise sort by reloc address below.
1174 else if (r2
.is_relative_
)
1178 unsigned int sym1
= this->get_symbol_index();
1179 unsigned int sym2
= r2
.get_symbol_index();
1182 else if (sym1
> sym2
)
1184 // Otherwise sort by reloc address.
1187 section_offset_type addr1
= this->get_address();
1188 section_offset_type addr2
= r2
.get_address();
1191 else if (addr1
> addr2
)
1194 // Final tie breaker, in order to generate the same output on any
1195 // host: reloc type.
1196 unsigned int type1
= this->type_
;
1197 unsigned int type2
= r2
.type_
;
1200 else if (type1
> type2
)
1203 // These relocs appear to be exactly the same.
1207 // Write out a Rela relocation.
1209 template<bool dynamic
, int size
, bool big_endian
>
1211 Output_reloc
<elfcpp::SHT_RELA
, dynamic
, size
, big_endian
>::write(
1212 unsigned char* pov
) const
1214 elfcpp::Rela_write
<size
, big_endian
> orel(pov
);
1215 this->rel_
.write_rel(&orel
);
1216 Addend addend
= this->addend_
;
1217 if (this->rel_
.is_target_specific())
1218 addend
= parameters
->target().reloc_addend(this->rel_
.target_arg(),
1219 this->rel_
.type(), addend
);
1220 else if (this->rel_
.is_symbolless())
1221 addend
= this->rel_
.symbol_value(addend
);
1222 else if (this->rel_
.is_local_section_symbol())
1223 addend
= this->rel_
.local_section_offset(addend
);
1224 orel
.put_r_addend(addend
);
1227 // Output_data_reloc_base methods.
1229 // Adjust the output section.
1231 template<int sh_type
, bool dynamic
, int size
, bool big_endian
>
1233 Output_data_reloc_base
<sh_type
, dynamic
, size
, big_endian
>
1234 ::do_adjust_output_section(Output_section
* os
)
1236 if (sh_type
== elfcpp::SHT_REL
)
1237 os
->set_entsize(elfcpp::Elf_sizes
<size
>::rel_size
);
1238 else if (sh_type
== elfcpp::SHT_RELA
)
1239 os
->set_entsize(elfcpp::Elf_sizes
<size
>::rela_size
);
1243 // A STT_GNU_IFUNC symbol may require a IRELATIVE reloc when doing a
1244 // static link. The backends will generate a dynamic reloc section
1245 // to hold this. In that case we don't want to link to the dynsym
1246 // section, because there isn't one.
1248 os
->set_should_link_to_symtab();
1249 else if (parameters
->doing_static_link())
1252 os
->set_should_link_to_dynsym();
1255 // Write out relocation data.
1257 template<int sh_type
, bool dynamic
, int size
, bool big_endian
>
1259 Output_data_reloc_base
<sh_type
, dynamic
, size
, big_endian
>::do_write(
1262 const off_t off
= this->offset();
1263 const off_t oview_size
= this->data_size();
1264 unsigned char* const oview
= of
->get_output_view(off
, oview_size
);
1266 if (this->sort_relocs())
1268 gold_assert(dynamic
);
1269 std::sort(this->relocs_
.begin(), this->relocs_
.end(),
1270 Sort_relocs_comparison());
1273 unsigned char* pov
= oview
;
1274 for (typename
Relocs::const_iterator p
= this->relocs_
.begin();
1275 p
!= this->relocs_
.end();
1282 gold_assert(pov
- oview
== oview_size
);
1284 of
->write_output_view(off
, oview_size
, oview
);
1286 // We no longer need the relocation entries.
1287 this->relocs_
.clear();
1290 // Class Output_relocatable_relocs.
1292 template<int sh_type
, int size
, bool big_endian
>
1294 Output_relocatable_relocs
<sh_type
, size
, big_endian
>::set_final_data_size()
1296 this->set_data_size(this->rr_
->output_reloc_count()
1297 * Reloc_types
<sh_type
, size
, big_endian
>::reloc_size
);
1300 // class Output_data_group.
1302 template<int size
, bool big_endian
>
1303 Output_data_group
<size
, big_endian
>::Output_data_group(
1304 Sized_relobj_file
<size
, big_endian
>* relobj
,
1305 section_size_type entry_count
,
1306 elfcpp::Elf_Word flags
,
1307 std::vector
<unsigned int>* input_shndxes
)
1308 : Output_section_data(entry_count
* 4, 4, false),
1312 this->input_shndxes_
.swap(*input_shndxes
);
1315 // Write out the section group, which means translating the section
1316 // indexes to apply to the output file.
1318 template<int size
, bool big_endian
>
1320 Output_data_group
<size
, big_endian
>::do_write(Output_file
* of
)
1322 const off_t off
= this->offset();
1323 const section_size_type oview_size
=
1324 convert_to_section_size_type(this->data_size());
1325 unsigned char* const oview
= of
->get_output_view(off
, oview_size
);
1327 elfcpp::Elf_Word
* contents
= reinterpret_cast<elfcpp::Elf_Word
*>(oview
);
1328 elfcpp::Swap
<32, big_endian
>::writeval(contents
, this->flags_
);
1331 for (std::vector
<unsigned int>::const_iterator p
=
1332 this->input_shndxes_
.begin();
1333 p
!= this->input_shndxes_
.end();
1336 Output_section
* os
= this->relobj_
->output_section(*p
);
1338 unsigned int output_shndx
;
1340 output_shndx
= os
->out_shndx();
1343 this->relobj_
->error(_("section group retained but "
1344 "group element discarded"));
1348 elfcpp::Swap
<32, big_endian
>::writeval(contents
, output_shndx
);
1351 size_t wrote
= reinterpret_cast<unsigned char*>(contents
) - oview
;
1352 gold_assert(wrote
== oview_size
);
1354 of
->write_output_view(off
, oview_size
, oview
);
1356 // We no longer need this information.
1357 this->input_shndxes_
.clear();
1360 // Output_data_got::Got_entry methods.
1362 // Write out the entry.
1364 template<int got_size
, bool big_endian
>
1366 Output_data_got
<got_size
, big_endian
>::Got_entry::write(
1367 unsigned int got_indx
,
1368 unsigned char* pov
) const
1372 switch (this->local_sym_index_
)
1376 // If the symbol is resolved locally, we need to write out the
1377 // link-time value, which will be relocated dynamically by a
1378 // RELATIVE relocation.
1379 Symbol
* gsym
= this->u_
.gsym
;
1380 if (this->use_plt_or_tls_offset_
&& gsym
->has_plt_offset())
1381 val
= parameters
->target().plt_address_for_global(gsym
);
1384 switch (parameters
->size_and_endianness())
1386 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
1387 case Parameters::TARGET_32_LITTLE
:
1388 case Parameters::TARGET_32_BIG
:
1390 // This cast is ugly. We don't want to put a
1391 // virtual method in Symbol, because we want Symbol
1392 // to be as small as possible.
1393 Sized_symbol
<32>::Value_type v
;
1394 v
= static_cast<Sized_symbol
<32>*>(gsym
)->value();
1395 val
= convert_types
<Valtype
, Sized_symbol
<32>::Value_type
>(v
);
1399 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
1400 case Parameters::TARGET_64_LITTLE
:
1401 case Parameters::TARGET_64_BIG
:
1403 Sized_symbol
<64>::Value_type v
;
1404 v
= static_cast<Sized_symbol
<64>*>(gsym
)->value();
1405 val
= convert_types
<Valtype
, Sized_symbol
<64>::Value_type
>(v
);
1412 if (this->use_plt_or_tls_offset_
1413 && gsym
->type() == elfcpp::STT_TLS
)
1414 val
+= parameters
->target().tls_offset_for_global(gsym
,
1421 val
= this->u_
.constant
;
1425 // If we're doing an incremental update, don't touch this GOT entry.
1426 if (parameters
->incremental_update())
1428 val
= this->u_
.constant
;
1433 const Relobj
* object
= this->u_
.object
;
1434 const unsigned int lsi
= this->local_sym_index_
;
1435 bool is_tls
= object
->local_is_tls(lsi
);
1436 if (this->use_plt_or_tls_offset_
&& !is_tls
)
1437 val
= parameters
->target().plt_address_for_local(object
, lsi
);
1440 uint64_t lval
= object
->local_symbol_value(lsi
, this->addend_
);
1441 val
= convert_types
<Valtype
, uint64_t>(lval
);
1442 if (this->use_plt_or_tls_offset_
&& is_tls
)
1443 val
+= parameters
->target().tls_offset_for_local(object
, lsi
,
1450 elfcpp::Swap
<got_size
, big_endian
>::writeval(pov
, val
);
1453 // Output_data_got methods.
1455 // Add an entry for a global symbol to the GOT. This returns true if
1456 // this is a new GOT entry, false if the symbol already had a GOT
1459 template<int got_size
, bool big_endian
>
1461 Output_data_got
<got_size
, big_endian
>::add_global(
1463 unsigned int got_type
)
1465 if (gsym
->has_got_offset(got_type
))
1468 unsigned int got_offset
= this->add_got_entry(Got_entry(gsym
, false));
1469 gsym
->set_got_offset(got_type
, got_offset
);
1473 // Like add_global, but use the PLT offset.
1475 template<int got_size
, bool big_endian
>
1477 Output_data_got
<got_size
, big_endian
>::add_global_plt(Symbol
* gsym
,
1478 unsigned int got_type
)
1480 if (gsym
->has_got_offset(got_type
))
1483 unsigned int got_offset
= this->add_got_entry(Got_entry(gsym
, true));
1484 gsym
->set_got_offset(got_type
, got_offset
);
1488 // Add an entry for a global symbol to the GOT, and add a dynamic
1489 // relocation of type R_TYPE for the GOT entry.
1491 template<int got_size
, bool big_endian
>
1493 Output_data_got
<got_size
, big_endian
>::add_global_with_rel(
1495 unsigned int got_type
,
1496 Output_data_reloc_generic
* rel_dyn
,
1497 unsigned int r_type
)
1499 if (gsym
->has_got_offset(got_type
))
1502 unsigned int got_offset
= this->add_got_entry(Got_entry());
1503 gsym
->set_got_offset(got_type
, got_offset
);
1504 rel_dyn
->add_global_generic(gsym
, r_type
, this, got_offset
, 0);
1507 // Add a pair of entries for a global symbol to the GOT, and add
1508 // dynamic relocations of type R_TYPE_1 and R_TYPE_2, respectively.
1509 // If R_TYPE_2 == 0, add the second entry with no relocation.
1510 template<int got_size
, bool big_endian
>
1512 Output_data_got
<got_size
, big_endian
>::add_global_pair_with_rel(
1514 unsigned int got_type
,
1515 Output_data_reloc_generic
* rel_dyn
,
1516 unsigned int r_type_1
,
1517 unsigned int r_type_2
)
1519 if (gsym
->has_got_offset(got_type
))
1522 unsigned int got_offset
= this->add_got_entry_pair(Got_entry(), Got_entry());
1523 gsym
->set_got_offset(got_type
, got_offset
);
1524 rel_dyn
->add_global_generic(gsym
, r_type_1
, this, got_offset
, 0);
1527 rel_dyn
->add_global_generic(gsym
, r_type_2
, this,
1528 got_offset
+ got_size
/ 8, 0);
1531 // Add an entry for a local symbol to the GOT. This returns true if
1532 // this is a new GOT entry, false if the symbol already has a GOT
1535 template<int got_size
, bool big_endian
>
1537 Output_data_got
<got_size
, big_endian
>::add_local(
1539 unsigned int symndx
,
1540 unsigned int got_type
)
1542 if (object
->local_has_got_offset(symndx
, got_type
))
1545 unsigned int got_offset
= this->add_got_entry(Got_entry(object
, symndx
,
1547 object
->set_local_got_offset(symndx
, got_type
, got_offset
);
1551 // Add an entry for a local symbol plus ADDEND to the GOT. This returns
1552 // true if this is a new GOT entry, false if the symbol already has a GOT
1555 template<int got_size
, bool big_endian
>
1557 Output_data_got
<got_size
, big_endian
>::add_local(
1559 unsigned int symndx
,
1560 unsigned int got_type
,
1563 if (object
->local_has_got_offset(symndx
, got_type
, addend
))
1566 unsigned int got_offset
= this->add_got_entry(Got_entry(object
, symndx
,
1568 object
->set_local_got_offset(symndx
, got_type
, got_offset
, addend
);
1572 // Like add_local, but use the PLT offset.
1574 template<int got_size
, bool big_endian
>
1576 Output_data_got
<got_size
, big_endian
>::add_local_plt(
1578 unsigned int symndx
,
1579 unsigned int got_type
)
1581 if (object
->local_has_got_offset(symndx
, got_type
))
1584 unsigned int got_offset
= this->add_got_entry(Got_entry(object
, symndx
,
1586 object
->set_local_got_offset(symndx
, got_type
, got_offset
);
1590 // Add an entry for a local symbol to the GOT, and add a dynamic
1591 // relocation of type R_TYPE for the GOT entry.
1593 template<int got_size
, bool big_endian
>
1595 Output_data_got
<got_size
, big_endian
>::add_local_with_rel(
1597 unsigned int symndx
,
1598 unsigned int got_type
,
1599 Output_data_reloc_generic
* rel_dyn
,
1600 unsigned int r_type
)
1602 if (object
->local_has_got_offset(symndx
, got_type
))
1605 unsigned int got_offset
= this->add_got_entry(Got_entry());
1606 object
->set_local_got_offset(symndx
, got_type
, got_offset
);
1607 rel_dyn
->add_local_generic(object
, symndx
, r_type
, this, got_offset
, 0);
1610 // Add an entry for a local symbol plus ADDEND to the GOT, and add a dynamic
1611 // relocation of type R_TYPE for the GOT entry.
1613 template<int got_size
, bool big_endian
>
1615 Output_data_got
<got_size
, big_endian
>::add_local_with_rel(
1617 unsigned int symndx
,
1618 unsigned int got_type
,
1619 Output_data_reloc_generic
* rel_dyn
,
1620 unsigned int r_type
, uint64_t addend
)
1622 if (object
->local_has_got_offset(symndx
, got_type
, addend
))
1625 unsigned int got_offset
= this->add_got_entry(Got_entry());
1626 object
->set_local_got_offset(symndx
, got_type
, got_offset
, addend
);
1627 rel_dyn
->add_local_generic(object
, symndx
, r_type
, this, got_offset
,
1631 // Add a pair of entries for a local symbol to the GOT, and add
1632 // a dynamic relocation of type R_TYPE using the section symbol of
1633 // the output section to which input section SHNDX maps, on the first.
1634 // The first got entry will have a value of zero, the second the
1635 // value of the local symbol.
1636 template<int got_size
, bool big_endian
>
1638 Output_data_got
<got_size
, big_endian
>::add_local_pair_with_rel(
1640 unsigned int symndx
,
1642 unsigned int got_type
,
1643 Output_data_reloc_generic
* rel_dyn
,
1644 unsigned int r_type
)
1646 if (object
->local_has_got_offset(symndx
, got_type
))
1649 unsigned int got_offset
=
1650 this->add_got_entry_pair(Got_entry(),
1651 Got_entry(object
, symndx
, false));
1652 object
->set_local_got_offset(symndx
, got_type
, got_offset
);
1653 Output_section
* os
= object
->output_section(shndx
);
1654 rel_dyn
->add_output_section_generic(os
, r_type
, this, got_offset
, 0);
1657 // Add a pair of entries for a local symbol plus ADDEND to the GOT, and add
1658 // a dynamic relocation of type R_TYPE using the section symbol of
1659 // the output section to which input section SHNDX maps, on the first.
1660 // The first got entry will have a value of zero, the second the
1661 // value of the local symbol.
1662 template<int got_size
, bool big_endian
>
1664 Output_data_got
<got_size
, big_endian
>::add_local_pair_with_rel(
1666 unsigned int symndx
,
1668 unsigned int got_type
,
1669 Output_data_reloc_generic
* rel_dyn
,
1670 unsigned int r_type
, uint64_t addend
)
1672 if (object
->local_has_got_offset(symndx
, got_type
, addend
))
1675 unsigned int got_offset
=
1676 this->add_got_entry_pair(Got_entry(),
1677 Got_entry(object
, symndx
, false, addend
));
1678 object
->set_local_got_offset(symndx
, got_type
, got_offset
, addend
);
1679 Output_section
* os
= object
->output_section(shndx
);
1680 rel_dyn
->add_output_section_generic(os
, r_type
, this, got_offset
, addend
);
1683 // Add a pair of entries for a local symbol to the GOT, and add
1684 // a dynamic relocation of type R_TYPE using STN_UNDEF on the first.
1685 // The first got entry will have a value of zero, the second the
1686 // value of the local symbol offset by Target::tls_offset_for_local.
1687 template<int got_size
, bool big_endian
>
1689 Output_data_got
<got_size
, big_endian
>::add_local_tls_pair(
1691 unsigned int symndx
,
1692 unsigned int got_type
,
1693 Output_data_reloc_generic
* rel_dyn
,
1694 unsigned int r_type
)
1696 if (object
->local_has_got_offset(symndx
, got_type
))
1699 unsigned int got_offset
1700 = this->add_got_entry_pair(Got_entry(),
1701 Got_entry(object
, symndx
, true));
1702 object
->set_local_got_offset(symndx
, got_type
, got_offset
);
1703 rel_dyn
->add_local_generic(object
, 0, r_type
, this, got_offset
, 0);
1706 // Reserve a slot in the GOT for a local symbol or the second slot of a pair.
1708 template<int got_size
, bool big_endian
>
1710 Output_data_got
<got_size
, big_endian
>::reserve_local(
1713 unsigned int sym_index
,
1714 unsigned int got_type
)
1716 this->do_reserve_slot(i
);
1717 object
->set_local_got_offset(sym_index
, got_type
, this->got_offset(i
));
1720 // Reserve a slot in the GOT for a global symbol.
1722 template<int got_size
, bool big_endian
>
1724 Output_data_got
<got_size
, big_endian
>::reserve_global(
1727 unsigned int got_type
)
1729 this->do_reserve_slot(i
);
1730 gsym
->set_got_offset(got_type
, this->got_offset(i
));
1733 // Write out the GOT.
1735 template<int got_size
, bool big_endian
>
1737 Output_data_got
<got_size
, big_endian
>::do_write(Output_file
* of
)
1739 const int add
= got_size
/ 8;
1741 const off_t off
= this->offset();
1742 const off_t oview_size
= this->data_size();
1743 unsigned char* const oview
= of
->get_output_view(off
, oview_size
);
1745 unsigned char* pov
= oview
;
1746 for (unsigned int i
= 0; i
< this->entries_
.size(); ++i
)
1748 this->entries_
[i
].write(i
, pov
);
1752 gold_assert(pov
- oview
== oview_size
);
1754 of
->write_output_view(off
, oview_size
, oview
);
1756 // We no longer need the GOT entries.
1757 this->entries_
.clear();
1760 // Create a new GOT entry and return its offset.
1762 template<int got_size
, bool big_endian
>
1764 Output_data_got
<got_size
, big_endian
>::add_got_entry(Got_entry got_entry
)
1766 if (!this->is_data_size_valid())
1768 this->entries_
.push_back(got_entry
);
1769 this->set_got_size();
1770 return this->last_got_offset();
1774 // For an incremental update, find an available slot.
1775 off_t got_offset
= this->free_list_
.allocate(got_size
/ 8,
1777 if (got_offset
== -1)
1778 gold_fallback(_("out of patch space (GOT);"
1779 " relink with --incremental-full"));
1780 unsigned int got_index
= got_offset
/ (got_size
/ 8);
1781 gold_assert(got_index
< this->entries_
.size());
1782 this->entries_
[got_index
] = got_entry
;
1783 return static_cast<unsigned int>(got_offset
);
1787 // Create a pair of new GOT entries and return the offset of the first.
1789 template<int got_size
, bool big_endian
>
1791 Output_data_got
<got_size
, big_endian
>::add_got_entry_pair(
1792 Got_entry got_entry_1
,
1793 Got_entry got_entry_2
)
1795 if (!this->is_data_size_valid())
1797 unsigned int got_offset
;
1798 this->entries_
.push_back(got_entry_1
);
1799 got_offset
= this->last_got_offset();
1800 this->entries_
.push_back(got_entry_2
);
1801 this->set_got_size();
1806 // For an incremental update, find an available pair of slots.
1807 off_t got_offset
= this->free_list_
.allocate(2 * got_size
/ 8,
1809 if (got_offset
== -1)
1810 gold_fallback(_("out of patch space (GOT);"
1811 " relink with --incremental-full"));
1812 unsigned int got_index
= got_offset
/ (got_size
/ 8);
1813 gold_assert(got_index
< this->entries_
.size());
1814 this->entries_
[got_index
] = got_entry_1
;
1815 this->entries_
[got_index
+ 1] = got_entry_2
;
1816 return static_cast<unsigned int>(got_offset
);
1820 // Replace GOT entry I with a new value.
1822 template<int got_size
, bool big_endian
>
1824 Output_data_got
<got_size
, big_endian
>::replace_got_entry(
1826 Got_entry got_entry
)
1828 gold_assert(i
< this->entries_
.size());
1829 this->entries_
[i
] = got_entry
;
1832 // Output_data_dynamic::Dynamic_entry methods.
1834 // Write out the entry.
1836 template<int size
, bool big_endian
>
1838 Output_data_dynamic::Dynamic_entry::write(
1840 const Stringpool
* pool
) const
1842 typename
elfcpp::Elf_types
<size
>::Elf_WXword val
;
1843 switch (this->offset_
)
1845 case DYNAMIC_NUMBER
:
1849 case DYNAMIC_SECTION_SIZE
:
1850 val
= this->u_
.od
->data_size();
1851 if (this->od2
!= NULL
)
1852 val
+= this->od2
->data_size();
1855 case DYNAMIC_SYMBOL
:
1857 const Sized_symbol
<size
>* s
=
1858 static_cast<const Sized_symbol
<size
>*>(this->u_
.sym
);
1863 case DYNAMIC_STRING
:
1864 val
= pool
->get_offset(this->u_
.str
);
1867 case DYNAMIC_CUSTOM
:
1868 val
= parameters
->target().dynamic_tag_custom_value(this->tag_
);
1872 val
= this->u_
.od
->address() + this->offset_
;
1876 elfcpp::Dyn_write
<size
, big_endian
> dw(pov
);
1877 dw
.put_d_tag(this->tag_
);
1881 // Output_data_dynamic methods.
1883 // Adjust the output section to set the entry size.
1886 Output_data_dynamic::do_adjust_output_section(Output_section
* os
)
1888 if (parameters
->target().get_size() == 32)
1889 os
->set_entsize(elfcpp::Elf_sizes
<32>::dyn_size
);
1890 else if (parameters
->target().get_size() == 64)
1891 os
->set_entsize(elfcpp::Elf_sizes
<64>::dyn_size
);
1896 // Set the final data size.
1899 Output_data_dynamic::set_final_data_size()
1901 // Add the terminating entry if it hasn't been added.
1902 // Because of relaxation, we can run this multiple times.
1903 if (this->entries_
.empty() || this->entries_
.back().tag() != elfcpp::DT_NULL
)
1905 int extra
= parameters
->options().spare_dynamic_tags();
1906 for (int i
= 0; i
< extra
; ++i
)
1907 this->add_constant(elfcpp::DT_NULL
, 0);
1908 this->add_constant(elfcpp::DT_NULL
, 0);
1912 if (parameters
->target().get_size() == 32)
1913 dyn_size
= elfcpp::Elf_sizes
<32>::dyn_size
;
1914 else if (parameters
->target().get_size() == 64)
1915 dyn_size
= elfcpp::Elf_sizes
<64>::dyn_size
;
1918 this->set_data_size(this->entries_
.size() * dyn_size
);
1921 // Write out the dynamic entries.
1924 Output_data_dynamic::do_write(Output_file
* of
)
1926 switch (parameters
->size_and_endianness())
1928 #ifdef HAVE_TARGET_32_LITTLE
1929 case Parameters::TARGET_32_LITTLE
:
1930 this->sized_write
<32, false>(of
);
1933 #ifdef HAVE_TARGET_32_BIG
1934 case Parameters::TARGET_32_BIG
:
1935 this->sized_write
<32, true>(of
);
1938 #ifdef HAVE_TARGET_64_LITTLE
1939 case Parameters::TARGET_64_LITTLE
:
1940 this->sized_write
<64, false>(of
);
1943 #ifdef HAVE_TARGET_64_BIG
1944 case Parameters::TARGET_64_BIG
:
1945 this->sized_write
<64, true>(of
);
1953 template<int size
, bool big_endian
>
1955 Output_data_dynamic::sized_write(Output_file
* of
)
1957 const int dyn_size
= elfcpp::Elf_sizes
<size
>::dyn_size
;
1959 const off_t offset
= this->offset();
1960 const off_t oview_size
= this->data_size();
1961 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
1963 unsigned char* pov
= oview
;
1964 for (typename
Dynamic_entries::const_iterator p
= this->entries_
.begin();
1965 p
!= this->entries_
.end();
1968 p
->write
<size
, big_endian
>(pov
, this->pool_
);
1972 gold_assert(pov
- oview
== oview_size
);
1974 of
->write_output_view(offset
, oview_size
, oview
);
1976 // We no longer need the dynamic entries.
1977 this->entries_
.clear();
1980 // Class Output_symtab_xindex.
1983 Output_symtab_xindex::do_write(Output_file
* of
)
1985 const off_t offset
= this->offset();
1986 const off_t oview_size
= this->data_size();
1987 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
1989 memset(oview
, 0, oview_size
);
1991 if (parameters
->target().is_big_endian())
1992 this->endian_do_write
<true>(oview
);
1994 this->endian_do_write
<false>(oview
);
1996 of
->write_output_view(offset
, oview_size
, oview
);
1998 // We no longer need the data.
1999 this->entries_
.clear();
2002 template<bool big_endian
>
2004 Output_symtab_xindex::endian_do_write(unsigned char* const oview
)
2006 for (Xindex_entries::const_iterator p
= this->entries_
.begin();
2007 p
!= this->entries_
.end();
2010 unsigned int symndx
= p
->first
;
2011 gold_assert(static_cast<off_t
>(symndx
) * 4 < this->data_size());
2012 elfcpp::Swap
<32, big_endian
>::writeval(oview
+ symndx
* 4, p
->second
);
2016 // Output_fill_debug_info methods.
2018 // Return the minimum size needed for a dummy compilation unit header.
2021 Output_fill_debug_info::do_minimum_hole_size() const
2023 // Compile unit header fields: unit_length, version, debug_abbrev_offset,
2025 const size_t len
= 4 + 2 + 4 + 1;
2026 // For type units, add type_signature, type_offset.
2027 if (this->is_debug_types_
)
2032 // Write a dummy compilation unit header to fill a hole in the
2033 // .debug_info or .debug_types section.
2036 Output_fill_debug_info::do_write(Output_file
* of
, off_t off
, size_t len
) const
2038 gold_debug(DEBUG_INCREMENTAL
, "fill_debug_info(%08lx, %08lx)",
2039 static_cast<long>(off
), static_cast<long>(len
));
2041 gold_assert(len
>= this->do_minimum_hole_size());
2043 unsigned char* const oview
= of
->get_output_view(off
, len
);
2044 unsigned char* pov
= oview
;
2046 // Write header fields: unit_length, version, debug_abbrev_offset,
2048 if (this->is_big_endian())
2050 elfcpp::Swap_unaligned
<32, true>::writeval(pov
, len
- 4);
2051 elfcpp::Swap_unaligned
<16, true>::writeval(pov
+ 4, this->version
);
2052 elfcpp::Swap_unaligned
<32, true>::writeval(pov
+ 6, 0);
2056 elfcpp::Swap_unaligned
<32, false>::writeval(pov
, len
- 4);
2057 elfcpp::Swap_unaligned
<16, false>::writeval(pov
+ 4, this->version
);
2058 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 6, 0);
2063 // For type units, the additional header fields -- type_signature,
2064 // type_offset -- can be filled with zeroes.
2066 // Fill the remainder of the free space with zeroes. The first
2067 // zero should tell the consumer there are no DIEs to read in this
2068 // compilation unit.
2069 if (pov
< oview
+ len
)
2070 memset(pov
, 0, oview
+ len
- pov
);
2072 of
->write_output_view(off
, len
, oview
);
2075 // Output_fill_debug_line methods.
2077 // Return the minimum size needed for a dummy line number program header.
2080 Output_fill_debug_line::do_minimum_hole_size() const
2082 // Line number program header fields: unit_length, version, header_length,
2083 // minimum_instruction_length, default_is_stmt, line_base, line_range,
2084 // opcode_base, standard_opcode_lengths[], include_directories, filenames.
2085 const size_t len
= 4 + 2 + 4 + this->header_length
;
2089 // Write a dummy line number program header to fill a hole in the
2090 // .debug_line section.
2093 Output_fill_debug_line::do_write(Output_file
* of
, off_t off
, size_t len
) const
2095 gold_debug(DEBUG_INCREMENTAL
, "fill_debug_line(%08lx, %08lx)",
2096 static_cast<long>(off
), static_cast<long>(len
));
2098 gold_assert(len
>= this->do_minimum_hole_size());
2100 unsigned char* const oview
= of
->get_output_view(off
, len
);
2101 unsigned char* pov
= oview
;
2103 // Write header fields: unit_length, version, header_length,
2104 // minimum_instruction_length, default_is_stmt, line_base, line_range,
2105 // opcode_base, standard_opcode_lengths[], include_directories, filenames.
2106 // We set the header_length field to cover the entire hole, so the
2107 // line number program is empty.
2108 if (this->is_big_endian())
2110 elfcpp::Swap_unaligned
<32, true>::writeval(pov
, len
- 4);
2111 elfcpp::Swap_unaligned
<16, true>::writeval(pov
+ 4, this->version
);
2112 elfcpp::Swap_unaligned
<32, true>::writeval(pov
+ 6, len
- (4 + 2 + 4));
2116 elfcpp::Swap_unaligned
<32, false>::writeval(pov
, len
- 4);
2117 elfcpp::Swap_unaligned
<16, false>::writeval(pov
+ 4, this->version
);
2118 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 6, len
- (4 + 2 + 4));
2121 *pov
++ = 1; // minimum_instruction_length
2122 *pov
++ = 0; // default_is_stmt
2123 *pov
++ = 0; // line_base
2124 *pov
++ = 5; // line_range
2125 *pov
++ = 13; // opcode_base
2126 *pov
++ = 0; // standard_opcode_lengths[1]
2127 *pov
++ = 1; // standard_opcode_lengths[2]
2128 *pov
++ = 1; // standard_opcode_lengths[3]
2129 *pov
++ = 1; // standard_opcode_lengths[4]
2130 *pov
++ = 1; // standard_opcode_lengths[5]
2131 *pov
++ = 0; // standard_opcode_lengths[6]
2132 *pov
++ = 0; // standard_opcode_lengths[7]
2133 *pov
++ = 0; // standard_opcode_lengths[8]
2134 *pov
++ = 1; // standard_opcode_lengths[9]
2135 *pov
++ = 0; // standard_opcode_lengths[10]
2136 *pov
++ = 0; // standard_opcode_lengths[11]
2137 *pov
++ = 1; // standard_opcode_lengths[12]
2138 *pov
++ = 0; // include_directories (empty)
2139 *pov
++ = 0; // filenames (empty)
2141 // Some consumers don't check the header_length field, and simply
2142 // start reading the line number program immediately following the
2143 // header. For those consumers, we fill the remainder of the free
2144 // space with DW_LNS_set_basic_block opcodes. These are effectively
2145 // no-ops: the resulting line table program will not create any rows.
2146 if (pov
< oview
+ len
)
2147 memset(pov
, elfcpp::DW_LNS_set_basic_block
, oview
+ len
- pov
);
2149 of
->write_output_view(off
, len
, oview
);
2152 // Output_section::Input_section methods.
2154 // Return the current data size. For an input section we store the size here.
2155 // For an Output_section_data, we have to ask it for the size.
2158 Output_section::Input_section::current_data_size() const
2160 if (this->is_input_section())
2161 return this->u1_
.data_size
;
2164 this->u2_
.posd
->pre_finalize_data_size();
2165 return this->u2_
.posd
->current_data_size();
2169 // Return the data size. For an input section we store the size here.
2170 // For an Output_section_data, we have to ask it for the size.
2173 Output_section::Input_section::data_size() const
2175 if (this->is_input_section())
2176 return this->u1_
.data_size
;
2178 return this->u2_
.posd
->data_size();
2181 // Return the object for an input section.
2184 Output_section::Input_section::relobj() const
2186 if (this->is_input_section())
2187 return this->u2_
.object
;
2188 else if (this->is_merge_section())
2190 gold_assert(this->u2_
.pomb
->first_relobj() != NULL
);
2191 return this->u2_
.pomb
->first_relobj();
2193 else if (this->is_relaxed_input_section())
2194 return this->u2_
.poris
->relobj();
2199 // Return the input section index for an input section.
2202 Output_section::Input_section::shndx() const
2204 if (this->is_input_section())
2205 return this->shndx_
;
2206 else if (this->is_merge_section())
2208 gold_assert(this->u2_
.pomb
->first_relobj() != NULL
);
2209 return this->u2_
.pomb
->first_shndx();
2211 else if (this->is_relaxed_input_section())
2212 return this->u2_
.poris
->shndx();
2217 // Set the address and file offset.
2220 Output_section::Input_section::set_address_and_file_offset(
2223 off_t section_file_offset
)
2225 if (this->is_input_section())
2226 this->u2_
.object
->set_section_offset(this->shndx_
,
2227 file_offset
- section_file_offset
);
2229 this->u2_
.posd
->set_address_and_file_offset(address
, file_offset
);
2232 // Reset the address and file offset.
2235 Output_section::Input_section::reset_address_and_file_offset()
2237 if (!this->is_input_section())
2238 this->u2_
.posd
->reset_address_and_file_offset();
2241 // Finalize the data size.
2244 Output_section::Input_section::finalize_data_size()
2246 if (!this->is_input_section())
2247 this->u2_
.posd
->finalize_data_size();
2250 // Try to turn an input offset into an output offset. We want to
2251 // return the output offset relative to the start of this
2252 // Input_section in the output section.
2255 Output_section::Input_section::output_offset(
2256 const Relobj
* object
,
2258 section_offset_type offset
,
2259 section_offset_type
* poutput
) const
2261 if (!this->is_input_section())
2262 return this->u2_
.posd
->output_offset(object
, shndx
, offset
, poutput
);
2265 if (this->shndx_
!= shndx
|| this->u2_
.object
!= object
)
2272 // Write out the data. We don't have to do anything for an input
2273 // section--they are handled via Object::relocate--but this is where
2274 // we write out the data for an Output_section_data.
2277 Output_section::Input_section::write(Output_file
* of
)
2279 if (!this->is_input_section())
2280 this->u2_
.posd
->write(of
);
2283 // Write the data to a buffer. As for write(), we don't have to do
2284 // anything for an input section.
2287 Output_section::Input_section::write_to_buffer(unsigned char* buffer
)
2289 if (!this->is_input_section())
2290 this->u2_
.posd
->write_to_buffer(buffer
);
2293 // Print to a map file.
2296 Output_section::Input_section::print_to_mapfile(Mapfile
* mapfile
) const
2298 switch (this->shndx_
)
2300 case OUTPUT_SECTION_CODE
:
2301 case MERGE_DATA_SECTION_CODE
:
2302 case MERGE_STRING_SECTION_CODE
:
2303 this->u2_
.posd
->print_to_mapfile(mapfile
);
2306 case RELAXED_INPUT_SECTION_CODE
:
2308 Output_relaxed_input_section
* relaxed_section
=
2309 this->relaxed_input_section();
2310 mapfile
->print_input_section(relaxed_section
->relobj(),
2311 relaxed_section
->shndx());
2315 mapfile
->print_input_section(this->u2_
.object
, this->shndx_
);
2320 // Output_section methods.
2322 // Construct an Output_section. NAME will point into a Stringpool.
2324 Output_section::Output_section(const char* name
, elfcpp::Elf_Word type
,
2325 elfcpp::Elf_Xword flags
)
2330 link_section_(NULL
),
2332 info_section_(NULL
),
2337 order_(ORDER_INVALID
),
2342 first_input_offset_(0),
2344 postprocessing_buffer_(NULL
),
2345 needs_symtab_index_(false),
2346 needs_dynsym_index_(false),
2347 should_link_to_symtab_(false),
2348 should_link_to_dynsym_(false),
2349 after_input_sections_(false),
2350 requires_postprocessing_(false),
2351 found_in_sections_clause_(false),
2352 has_load_address_(false),
2353 info_uses_section_index_(false),
2354 input_section_order_specified_(false),
2355 may_sort_attached_input_sections_(false),
2356 must_sort_attached_input_sections_(false),
2357 attached_input_sections_are_sorted_(false),
2359 is_small_section_(false),
2360 is_large_section_(false),
2361 generate_code_fills_at_write_(false),
2362 is_entsize_zero_(false),
2363 section_offsets_need_adjustment_(false),
2365 always_keeps_input_sections_(false),
2366 has_fixed_layout_(false),
2367 is_patch_space_allowed_(false),
2368 is_unique_segment_(false),
2370 extra_segment_flags_(0),
2371 segment_alignment_(0),
2373 lookup_maps_(new Output_section_lookup_maps
),
2375 free_space_fill_(NULL
),
2378 // An unallocated section has no address. Forcing this means that
2379 // we don't need special treatment for symbols defined in debug
2381 if ((flags
& elfcpp::SHF_ALLOC
) == 0)
2382 this->set_address(0);
2385 Output_section::~Output_section()
2387 delete this->checkpoint_
;
2390 // Set the entry size.
2393 Output_section::set_entsize(uint64_t v
)
2395 if (this->is_entsize_zero_
)
2397 else if (this->entsize_
== 0)
2399 else if (this->entsize_
!= v
)
2402 this->is_entsize_zero_
= 1;
2406 // Add the input section SHNDX, with header SHDR, named SECNAME, in
2407 // OBJECT, to the Output_section. RELOC_SHNDX is the index of a
2408 // relocation section which applies to this section, or 0 if none, or
2409 // -1U if more than one. Return the offset of the input section
2410 // within the output section. Return -1 if the input section will
2411 // receive special handling. In the normal case we don't always keep
2412 // track of input sections for an Output_section. Instead, each
2413 // Object keeps track of the Output_section for each of its input
2414 // sections. However, if HAVE_SECTIONS_SCRIPT is true, we do keep
2415 // track of input sections here; this is used when SECTIONS appears in
2418 template<int size
, bool big_endian
>
2420 Output_section::add_input_section(Layout
* layout
,
2421 Sized_relobj_file
<size
, big_endian
>* object
,
2423 const char* secname
,
2424 const elfcpp::Shdr
<size
, big_endian
>& shdr
,
2425 unsigned int reloc_shndx
,
2426 bool have_sections_script
)
2428 elfcpp::Elf_Xword addralign
= shdr
.get_sh_addralign();
2429 if ((addralign
& (addralign
- 1)) != 0)
2431 object
->error(_("invalid alignment %lu for section \"%s\""),
2432 static_cast<unsigned long>(addralign
), secname
);
2436 if (addralign
> this->addralign_
)
2437 this->addralign_
= addralign
;
2439 typename
elfcpp::Elf_types
<size
>::Elf_WXword sh_flags
= shdr
.get_sh_flags();
2440 uint64_t entsize
= shdr
.get_sh_entsize();
2442 // .debug_str is a mergeable string section, but is not always so
2443 // marked by compilers. Mark manually here so we can optimize.
2444 if (strcmp(secname
, ".debug_str") == 0)
2446 sh_flags
|= (elfcpp::SHF_MERGE
| elfcpp::SHF_STRINGS
);
2450 this->update_flags_for_input_section(sh_flags
);
2451 this->set_entsize(entsize
);
2453 // If this is a SHF_MERGE section, we pass all the input sections to
2454 // a Output_data_merge. We don't try to handle relocations for such
2455 // a section. We don't try to handle empty merge sections--they
2456 // mess up the mappings, and are useless anyhow.
2457 // FIXME: Need to handle merge sections during incremental update.
2458 if ((sh_flags
& elfcpp::SHF_MERGE
) != 0
2460 && shdr
.get_sh_size() > 0
2461 && !parameters
->incremental())
2463 // Keep information about merged input sections for rebuilding fast
2464 // lookup maps if we have sections-script or we do relaxation.
2465 bool keeps_input_sections
= (this->always_keeps_input_sections_
2466 || have_sections_script
2467 || parameters
->target().may_relax());
2469 if (this->add_merge_input_section(object
, shndx
, sh_flags
, entsize
,
2470 addralign
, keeps_input_sections
))
2472 // Tell the relocation routines that they need to call the
2473 // output_offset method to determine the final address.
2478 section_size_type input_section_size
= shdr
.get_sh_size();
2479 section_size_type uncompressed_size
;
2480 if (object
->section_is_compressed(shndx
, &uncompressed_size
))
2481 input_section_size
= uncompressed_size
;
2483 off_t offset_in_section
;
2485 if (this->has_fixed_layout())
2487 // For incremental updates, find a chunk of unused space in the section.
2488 offset_in_section
= this->free_list_
.allocate(input_section_size
,
2490 if (offset_in_section
== -1)
2491 gold_fallback(_("out of patch space in section %s; "
2492 "relink with --incremental-full"),
2494 return offset_in_section
;
2497 offset_in_section
= this->current_data_size_for_child();
2498 off_t aligned_offset_in_section
= align_address(offset_in_section
,
2500 this->set_current_data_size_for_child(aligned_offset_in_section
2501 + input_section_size
);
2503 // Determine if we want to delay code-fill generation until the output
2504 // section is written. When the target is relaxing, we want to delay fill
2505 // generating to avoid adjusting them during relaxation. Also, if we are
2506 // sorting input sections we must delay fill generation.
2507 if (!this->generate_code_fills_at_write_
2508 && !have_sections_script
2509 && (sh_flags
& elfcpp::SHF_EXECINSTR
) != 0
2510 && parameters
->target().has_code_fill()
2511 && (parameters
->target().may_relax()
2512 || layout
->is_section_ordering_specified()))
2514 gold_assert(this->fills_
.empty());
2515 this->generate_code_fills_at_write_
= true;
2518 if (aligned_offset_in_section
> offset_in_section
2519 && !this->generate_code_fills_at_write_
2520 && !have_sections_script
2521 && (sh_flags
& elfcpp::SHF_EXECINSTR
) != 0
2522 && parameters
->target().has_code_fill())
2524 // We need to add some fill data. Using fill_list_ when
2525 // possible is an optimization, since we will often have fill
2526 // sections without input sections.
2527 off_t fill_len
= aligned_offset_in_section
- offset_in_section
;
2528 if (this->input_sections_
.empty())
2529 this->fills_
.push_back(Fill(offset_in_section
, fill_len
));
2532 std::string
fill_data(parameters
->target().code_fill(fill_len
));
2533 Output_data_const
* odc
= new Output_data_const(fill_data
, 1);
2534 this->input_sections_
.push_back(Input_section(odc
));
2538 // We need to keep track of this section if we are already keeping
2539 // track of sections, or if we are relaxing. Also, if this is a
2540 // section which requires sorting, or which may require sorting in
2541 // the future, we keep track of the sections. If the
2542 // --section-ordering-file option is used to specify the order of
2543 // sections, we need to keep track of sections.
2544 if (this->always_keeps_input_sections_
2545 || have_sections_script
2546 || !this->input_sections_
.empty()
2547 || this->may_sort_attached_input_sections()
2548 || this->must_sort_attached_input_sections()
2549 || parameters
->options().user_set_Map()
2550 || parameters
->target().may_relax()
2551 || layout
->is_section_ordering_specified())
2553 Input_section
isecn(object
, shndx
, input_section_size
, addralign
);
2554 /* If section ordering is requested by specifying a ordering file,
2555 using --section-ordering-file, match the section name with
2557 if (parameters
->options().section_ordering_file())
2559 unsigned int section_order_index
=
2560 layout
->find_section_order_index(std::string(secname
));
2561 if (section_order_index
!= 0)
2563 isecn
.set_section_order_index(section_order_index
);
2564 this->set_input_section_order_specified();
2567 this->input_sections_
.push_back(isecn
);
2570 return aligned_offset_in_section
;
2573 // Add arbitrary data to an output section.
2576 Output_section::add_output_section_data(Output_section_data
* posd
)
2578 Input_section
inp(posd
);
2579 this->add_output_section_data(&inp
);
2581 if (posd
->is_data_size_valid())
2583 off_t offset_in_section
;
2584 if (this->has_fixed_layout())
2586 // For incremental updates, find a chunk of unused space.
2587 offset_in_section
= this->free_list_
.allocate(posd
->data_size(),
2588 posd
->addralign(), 0);
2589 if (offset_in_section
== -1)
2590 gold_fallback(_("out of patch space in section %s; "
2591 "relink with --incremental-full"),
2593 // Finalize the address and offset now.
2594 uint64_t addr
= this->address();
2595 off_t offset
= this->offset();
2596 posd
->set_address_and_file_offset(addr
+ offset_in_section
,
2597 offset
+ offset_in_section
);
2601 offset_in_section
= this->current_data_size_for_child();
2602 off_t aligned_offset_in_section
= align_address(offset_in_section
,
2604 this->set_current_data_size_for_child(aligned_offset_in_section
2605 + posd
->data_size());
2608 else if (this->has_fixed_layout())
2610 // For incremental updates, arrange for the data to have a fixed layout.
2611 // This will mean that additions to the data must be allocated from
2612 // free space within the containing output section.
2613 uint64_t addr
= this->address();
2614 posd
->set_address(addr
);
2615 posd
->set_file_offset(0);
2616 // FIXME: This should eventually be unreachable.
2617 // gold_unreachable();
2621 // Add a relaxed input section.
2624 Output_section::add_relaxed_input_section(Layout
* layout
,
2625 Output_relaxed_input_section
* poris
,
2626 const std::string
& name
)
2628 Input_section
inp(poris
);
2630 // If the --section-ordering-file option is used to specify the order of
2631 // sections, we need to keep track of sections.
2632 if (layout
->is_section_ordering_specified())
2634 unsigned int section_order_index
=
2635 layout
->find_section_order_index(name
);
2636 if (section_order_index
!= 0)
2638 inp
.set_section_order_index(section_order_index
);
2639 this->set_input_section_order_specified();
2643 this->add_output_section_data(&inp
);
2644 if (this->lookup_maps_
->is_valid())
2645 this->lookup_maps_
->add_relaxed_input_section(poris
->relobj(),
2646 poris
->shndx(), poris
);
2648 // For a relaxed section, we use the current data size. Linker scripts
2649 // get all the input sections, including relaxed one from an output
2650 // section and add them back to the same output section to compute the
2651 // output section size. If we do not account for sizes of relaxed input
2652 // sections, an output section would be incorrectly sized.
2653 off_t offset_in_section
= this->current_data_size_for_child();
2654 off_t aligned_offset_in_section
= align_address(offset_in_section
,
2655 poris
->addralign());
2656 this->set_current_data_size_for_child(aligned_offset_in_section
2657 + poris
->current_data_size());
2660 // Add arbitrary data to an output section by Input_section.
2663 Output_section::add_output_section_data(Input_section
* inp
)
2665 if (this->input_sections_
.empty())
2666 this->first_input_offset_
= this->current_data_size_for_child();
2668 this->input_sections_
.push_back(*inp
);
2670 uint64_t addralign
= inp
->addralign();
2671 if (addralign
> this->addralign_
)
2672 this->addralign_
= addralign
;
2674 inp
->set_output_section(this);
2677 // Add a merge section to an output section.
2680 Output_section::add_output_merge_section(Output_section_data
* posd
,
2681 bool is_string
, uint64_t entsize
)
2683 Input_section
inp(posd
, is_string
, entsize
);
2684 this->add_output_section_data(&inp
);
2687 // Add an input section to a SHF_MERGE section.
2690 Output_section::add_merge_input_section(Relobj
* object
, unsigned int shndx
,
2691 uint64_t flags
, uint64_t entsize
,
2693 bool keeps_input_sections
)
2695 // We cannot merge sections with entsize == 0.
2699 bool is_string
= (flags
& elfcpp::SHF_STRINGS
) != 0;
2701 // We cannot restore merged input section states.
2702 gold_assert(this->checkpoint_
== NULL
);
2704 // Look up merge sections by required properties.
2705 // Currently, we only invalidate the lookup maps in script processing
2706 // and relaxation. We should not have done either when we reach here.
2707 // So we assume that the lookup maps are valid to simply code.
2708 gold_assert(this->lookup_maps_
->is_valid());
2709 Merge_section_properties
msp(is_string
, entsize
, addralign
);
2710 Output_merge_base
* pomb
= this->lookup_maps_
->find_merge_section(msp
);
2711 bool is_new
= false;
2714 gold_assert(pomb
->is_string() == is_string
2715 && pomb
->entsize() == entsize
2716 && pomb
->addralign() == addralign
);
2720 // Create a new Output_merge_data or Output_merge_string_data.
2722 pomb
= new Output_merge_data(entsize
, addralign
);
2728 pomb
= new Output_merge_string
<char>(addralign
);
2731 pomb
= new Output_merge_string
<uint16_t>(addralign
);
2734 pomb
= new Output_merge_string
<uint32_t>(addralign
);
2740 // If we need to do script processing or relaxation, we need to keep
2741 // the original input sections to rebuild the fast lookup maps.
2742 if (keeps_input_sections
)
2743 pomb
->set_keeps_input_sections();
2747 if (pomb
->add_input_section(object
, shndx
))
2749 // Add new merge section to this output section and link merge
2750 // section properties to new merge section in map.
2753 this->add_output_merge_section(pomb
, is_string
, entsize
);
2754 this->lookup_maps_
->add_merge_section(msp
, pomb
);
2761 // If add_input_section failed, delete new merge section to avoid
2762 // exporting empty merge sections in Output_section::get_input_section.
2769 // Build a relaxation map to speed up relaxation of existing input sections.
2770 // Look up to the first LIMIT elements in INPUT_SECTIONS.
2773 Output_section::build_relaxation_map(
2774 const Input_section_list
& input_sections
,
2776 Relaxation_map
* relaxation_map
) const
2778 for (size_t i
= 0; i
< limit
; ++i
)
2780 const Input_section
& is(input_sections
[i
]);
2781 if (is
.is_input_section() || is
.is_relaxed_input_section())
2783 Section_id
sid(is
.relobj(), is
.shndx());
2784 (*relaxation_map
)[sid
] = i
;
2789 // Convert regular input sections in INPUT_SECTIONS into relaxed input
2790 // sections in RELAXED_SECTIONS. MAP is a prebuilt map from section id
2791 // indices of INPUT_SECTIONS.
2794 Output_section::convert_input_sections_in_list_to_relaxed_sections(
2795 const std::vector
<Output_relaxed_input_section
*>& relaxed_sections
,
2796 const Relaxation_map
& map
,
2797 Input_section_list
* input_sections
)
2799 for (size_t i
= 0; i
< relaxed_sections
.size(); ++i
)
2801 Output_relaxed_input_section
* poris
= relaxed_sections
[i
];
2802 Section_id
sid(poris
->relobj(), poris
->shndx());
2803 Relaxation_map::const_iterator p
= map
.find(sid
);
2804 gold_assert(p
!= map
.end());
2805 gold_assert((*input_sections
)[p
->second
].is_input_section());
2807 // Remember section order index of original input section
2808 // if it is set. Copy it to the relaxed input section.
2810 (*input_sections
)[p
->second
].section_order_index();
2811 (*input_sections
)[p
->second
] = Input_section(poris
);
2812 (*input_sections
)[p
->second
].set_section_order_index(soi
);
2816 // Convert regular input sections into relaxed input sections. RELAXED_SECTIONS
2817 // is a vector of pointers to Output_relaxed_input_section or its derived
2818 // classes. The relaxed sections must correspond to existing input sections.
2821 Output_section::convert_input_sections_to_relaxed_sections(
2822 const std::vector
<Output_relaxed_input_section
*>& relaxed_sections
)
2824 gold_assert(parameters
->target().may_relax());
2826 // We want to make sure that restore_states does not undo the effect of
2827 // this. If there is no checkpoint active, just search the current
2828 // input section list and replace the sections there. If there is
2829 // a checkpoint, also replace the sections there.
2831 // By default, we look at the whole list.
2832 size_t limit
= this->input_sections_
.size();
2834 if (this->checkpoint_
!= NULL
)
2836 // Replace input sections with relaxed input section in the saved
2837 // copy of the input section list.
2838 if (this->checkpoint_
->input_sections_saved())
2841 this->build_relaxation_map(
2842 *(this->checkpoint_
->input_sections()),
2843 this->checkpoint_
->input_sections()->size(),
2845 this->convert_input_sections_in_list_to_relaxed_sections(
2848 this->checkpoint_
->input_sections());
2852 // We have not copied the input section list yet. Instead, just
2853 // look at the portion that would be saved.
2854 limit
= this->checkpoint_
->input_sections_size();
2858 // Convert input sections in input_section_list.
2860 this->build_relaxation_map(this->input_sections_
, limit
, &map
);
2861 this->convert_input_sections_in_list_to_relaxed_sections(
2864 &this->input_sections_
);
2866 // Update fast look-up map.
2867 if (this->lookup_maps_
->is_valid())
2868 for (size_t i
= 0; i
< relaxed_sections
.size(); ++i
)
2870 Output_relaxed_input_section
* poris
= relaxed_sections
[i
];
2871 this->lookup_maps_
->add_relaxed_input_section(poris
->relobj(),
2872 poris
->shndx(), poris
);
2876 // Update the output section flags based on input section flags.
2879 Output_section::update_flags_for_input_section(elfcpp::Elf_Xword flags
)
2881 // If we created the section with SHF_ALLOC clear, we set the
2882 // address. If we are now setting the SHF_ALLOC flag, we need to
2884 if ((this->flags_
& elfcpp::SHF_ALLOC
) == 0
2885 && (flags
& elfcpp::SHF_ALLOC
) != 0)
2886 this->mark_address_invalid();
2888 this->flags_
|= (flags
2889 & (elfcpp::SHF_WRITE
2891 | elfcpp::SHF_EXECINSTR
));
2893 if ((flags
& elfcpp::SHF_MERGE
) == 0)
2894 this->flags_
&=~ elfcpp::SHF_MERGE
;
2897 if (this->current_data_size_for_child() == 0)
2898 this->flags_
|= elfcpp::SHF_MERGE
;
2901 if ((flags
& elfcpp::SHF_STRINGS
) == 0)
2902 this->flags_
&=~ elfcpp::SHF_STRINGS
;
2905 if (this->current_data_size_for_child() == 0)
2906 this->flags_
|= elfcpp::SHF_STRINGS
;
2910 // Find the merge section into which an input section with index SHNDX in
2911 // OBJECT has been added. Return NULL if none found.
2913 const Output_section_data
*
2914 Output_section::find_merge_section(const Relobj
* object
,
2915 unsigned int shndx
) const
2917 return object
->find_merge_section(shndx
);
2920 // Build the lookup maps for relaxed sections. This needs
2921 // to be declared as a const method so that it is callable with a const
2922 // Output_section pointer. The method only updates states of the maps.
2925 Output_section::build_lookup_maps() const
2927 this->lookup_maps_
->clear();
2928 for (Input_section_list::const_iterator p
= this->input_sections_
.begin();
2929 p
!= this->input_sections_
.end();
2932 if (p
->is_relaxed_input_section())
2934 Output_relaxed_input_section
* poris
= p
->relaxed_input_section();
2935 this->lookup_maps_
->add_relaxed_input_section(poris
->relobj(),
2936 poris
->shndx(), poris
);
2941 // Find an relaxed input section corresponding to an input section
2942 // in OBJECT with index SHNDX.
2944 const Output_relaxed_input_section
*
2945 Output_section::find_relaxed_input_section(const Relobj
* object
,
2946 unsigned int shndx
) const
2948 if (!this->lookup_maps_
->is_valid())
2949 this->build_lookup_maps();
2950 return this->lookup_maps_
->find_relaxed_input_section(object
, shndx
);
2953 // Given an address OFFSET relative to the start of input section
2954 // SHNDX in OBJECT, return whether this address is being included in
2955 // the final link. This should only be called if SHNDX in OBJECT has
2956 // a special mapping.
2959 Output_section::is_input_address_mapped(const Relobj
* object
,
2963 // Look at the Output_section_data_maps first.
2964 const Output_section_data
* posd
= this->find_merge_section(object
, shndx
);
2966 posd
= this->find_relaxed_input_section(object
, shndx
);
2970 section_offset_type output_offset
;
2971 bool found
= posd
->output_offset(object
, shndx
, offset
, &output_offset
);
2972 // By default we assume that the address is mapped. See comment at the
2976 return output_offset
!= -1;
2979 // Fall back to the slow look-up.
2980 for (Input_section_list::const_iterator p
= this->input_sections_
.begin();
2981 p
!= this->input_sections_
.end();
2984 section_offset_type output_offset
;
2985 if (p
->output_offset(object
, shndx
, offset
, &output_offset
))
2986 return output_offset
!= -1;
2989 // By default we assume that the address is mapped. This should
2990 // only be called after we have passed all sections to Layout. At
2991 // that point we should know what we are discarding.
2995 // Given an address OFFSET relative to the start of input section
2996 // SHNDX in object OBJECT, return the output offset relative to the
2997 // start of the input section in the output section. This should only
2998 // be called if SHNDX in OBJECT has a special mapping.
3001 Output_section::output_offset(const Relobj
* object
, unsigned int shndx
,
3002 section_offset_type offset
) const
3004 // This can only be called meaningfully when we know the data size
3006 gold_assert(this->is_data_size_valid());
3008 // Look at the Output_section_data_maps first.
3009 const Output_section_data
* posd
= this->find_merge_section(object
, shndx
);
3011 posd
= this->find_relaxed_input_section(object
, shndx
);
3014 section_offset_type output_offset
;
3015 bool found
= posd
->output_offset(object
, shndx
, offset
, &output_offset
);
3017 return output_offset
;
3020 // Fall back to the slow look-up.
3021 for (Input_section_list::const_iterator p
= this->input_sections_
.begin();
3022 p
!= this->input_sections_
.end();
3025 section_offset_type output_offset
;
3026 if (p
->output_offset(object
, shndx
, offset
, &output_offset
))
3027 return output_offset
;
3032 // Return the output virtual address of OFFSET relative to the start
3033 // of input section SHNDX in object OBJECT.
3036 Output_section::output_address(const Relobj
* object
, unsigned int shndx
,
3039 uint64_t addr
= this->address() + this->first_input_offset_
;
3041 // Look at the Output_section_data_maps first.
3042 const Output_section_data
* posd
= this->find_merge_section(object
, shndx
);
3044 posd
= this->find_relaxed_input_section(object
, shndx
);
3045 if (posd
!= NULL
&& posd
->is_address_valid())
3047 section_offset_type output_offset
;
3048 bool found
= posd
->output_offset(object
, shndx
, offset
, &output_offset
);
3050 return posd
->address() + output_offset
;
3053 // Fall back to the slow look-up.
3054 for (Input_section_list::const_iterator p
= this->input_sections_
.begin();
3055 p
!= this->input_sections_
.end();
3058 addr
= align_address(addr
, p
->addralign());
3059 section_offset_type output_offset
;
3060 if (p
->output_offset(object
, shndx
, offset
, &output_offset
))
3062 if (output_offset
== -1)
3064 return addr
+ output_offset
;
3066 addr
+= p
->data_size();
3069 // If we get here, it means that we don't know the mapping for this
3070 // input section. This might happen in principle if
3071 // add_input_section were called before add_output_section_data.
3072 // But it should never actually happen.
3077 // Find the output address of the start of the merged section for
3078 // input section SHNDX in object OBJECT.
3081 Output_section::find_starting_output_address(const Relobj
* object
,
3083 uint64_t* paddr
) const
3085 const Output_section_data
* data
= this->find_merge_section(object
, shndx
);
3089 // FIXME: This becomes a bottle-neck if we have many relaxed sections.
3090 // Looking up the merge section map does not always work as we sometimes
3091 // find a merge section without its address set.
3092 uint64_t addr
= this->address() + this->first_input_offset_
;
3093 for (Input_section_list::const_iterator p
= this->input_sections_
.begin();
3094 p
!= this->input_sections_
.end();
3097 addr
= align_address(addr
, p
->addralign());
3099 // It would be nice if we could use the existing output_offset
3100 // method to get the output offset of input offset 0.
3101 // Unfortunately we don't know for sure that input offset 0 is
3103 if (!p
->is_input_section() && p
->output_section_data() == data
)
3109 addr
+= p
->data_size();
3112 // We couldn't find a merge output section for this input section.
3116 // Update the data size of an Output_section.
3119 Output_section::update_data_size()
3121 if (this->input_sections_
.empty())
3124 if (this->must_sort_attached_input_sections()
3125 || this->input_section_order_specified())
3126 this->sort_attached_input_sections();
3128 off_t off
= this->first_input_offset_
;
3129 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3130 p
!= this->input_sections_
.end();
3133 off
= align_address(off
, p
->addralign());
3134 off
+= p
->current_data_size();
3137 this->set_current_data_size_for_child(off
);
3140 // Set the data size of an Output_section. This is where we handle
3141 // setting the addresses of any Output_section_data objects.
3144 Output_section::set_final_data_size()
3148 if (this->input_sections_
.empty())
3149 data_size
= this->current_data_size_for_child();
3152 if (this->must_sort_attached_input_sections()
3153 || this->input_section_order_specified())
3154 this->sort_attached_input_sections();
3156 uint64_t address
= this->address();
3157 off_t startoff
= this->offset();
3158 off_t off
= startoff
+ this->first_input_offset_
;
3159 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3160 p
!= this->input_sections_
.end();
3163 off
= align_address(off
, p
->addralign());
3164 p
->set_address_and_file_offset(address
+ (off
- startoff
), off
,
3166 off
+= p
->data_size();
3168 data_size
= off
- startoff
;
3171 // For full incremental links, we want to allocate some patch space
3172 // in most sections for subsequent incremental updates.
3173 if (this->is_patch_space_allowed_
&& parameters
->incremental_full())
3175 double pct
= parameters
->options().incremental_patch();
3176 size_t extra
= static_cast<size_t>(data_size
* pct
);
3177 if (this->free_space_fill_
!= NULL
3178 && this->free_space_fill_
->minimum_hole_size() > extra
)
3179 extra
= this->free_space_fill_
->minimum_hole_size();
3180 off_t new_size
= align_address(data_size
+ extra
, this->addralign());
3181 this->patch_space_
= new_size
- data_size
;
3182 gold_debug(DEBUG_INCREMENTAL
,
3183 "set_final_data_size: %08lx + %08lx: section %s",
3184 static_cast<long>(data_size
),
3185 static_cast<long>(this->patch_space_
),
3187 data_size
= new_size
;
3190 this->set_data_size(data_size
);
3193 // Reset the address and file offset.
3196 Output_section::do_reset_address_and_file_offset()
3198 // An unallocated section has no address. Forcing this means that
3199 // we don't need special treatment for symbols defined in debug
3200 // sections. We do the same in the constructor. This does not
3201 // apply to NOLOAD sections though.
3202 if (((this->flags_
& elfcpp::SHF_ALLOC
) == 0) && !this->is_noload_
)
3203 this->set_address(0);
3205 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3206 p
!= this->input_sections_
.end();
3208 p
->reset_address_and_file_offset();
3210 // Remove any patch space that was added in set_final_data_size.
3211 if (this->patch_space_
> 0)
3213 this->set_current_data_size_for_child(this->current_data_size_for_child()
3214 - this->patch_space_
);
3215 this->patch_space_
= 0;
3219 // Return true if address and file offset have the values after reset.
3222 Output_section::do_address_and_file_offset_have_reset_values() const
3224 if (this->is_offset_valid())
3227 // An unallocated section has address 0 after its construction or a reset.
3228 if ((this->flags_
& elfcpp::SHF_ALLOC
) == 0)
3229 return this->is_address_valid() && this->address() == 0;
3231 return !this->is_address_valid();
3234 // Set the TLS offset. Called only for SHT_TLS sections.
3237 Output_section::do_set_tls_offset(uint64_t tls_base
)
3239 this->tls_offset_
= this->address() - tls_base
;
3242 // In a few cases we need to sort the input sections attached to an
3243 // output section. This is used to implement the type of constructor
3244 // priority ordering implemented by the GNU linker, in which the
3245 // priority becomes part of the section name and the sections are
3246 // sorted by name. We only do this for an output section if we see an
3247 // attached input section matching ".ctors.*", ".dtors.*",
3248 // ".init_array.*" or ".fini_array.*".
3250 class Output_section::Input_section_sort_entry
3253 Input_section_sort_entry()
3254 : input_section_(), index_(-1U), section_name_()
3257 Input_section_sort_entry(const Input_section
& input_section
,
3259 bool must_sort_attached_input_sections
,
3260 const char* output_section_name
)
3261 : input_section_(input_section
), index_(index
), section_name_()
3263 if ((input_section
.is_input_section()
3264 || input_section
.is_relaxed_input_section())
3265 && must_sort_attached_input_sections
)
3267 // This is only called single-threaded from Layout::finalize,
3268 // so it is OK to lock. Unfortunately we have no way to pass
3270 const Task
* dummy_task
= reinterpret_cast<const Task
*>(-1);
3271 Object
* obj
= (input_section
.is_input_section()
3272 ? input_section
.relobj()
3273 : input_section
.relaxed_input_section()->relobj());
3274 Task_lock_obj
<Object
> tl(dummy_task
, obj
);
3276 // This is a slow operation, which should be cached in
3277 // Layout::layout if this becomes a speed problem.
3278 this->section_name_
= obj
->section_name(input_section
.shndx());
3280 else if (input_section
.is_output_section_data()
3281 && must_sort_attached_input_sections
)
3283 // For linker-generated sections, use the output section name.
3284 this->section_name_
.assign(output_section_name
);
3288 // Return the Input_section.
3289 const Input_section
&
3290 input_section() const
3292 gold_assert(this->index_
!= -1U);
3293 return this->input_section_
;
3296 // The index of this entry in the original list. This is used to
3297 // make the sort stable.
3301 gold_assert(this->index_
!= -1U);
3302 return this->index_
;
3305 // The section name.
3307 section_name() const
3309 return this->section_name_
;
3312 // Return true if the section name has a priority. This is assumed
3313 // to be true if it has a dot after the initial dot.
3315 has_priority() const
3317 return this->section_name_
.find('.', 1) != std::string::npos
;
3320 // Return the priority. Believe it or not, gcc encodes the priority
3321 // differently for .ctors/.dtors and .init_array/.fini_array
3324 get_priority() const
3327 if (is_prefix_of(".ctors.", this->section_name_
.c_str())
3328 || is_prefix_of(".dtors.", this->section_name_
.c_str()))
3330 else if (is_prefix_of(".init_array.", this->section_name_
.c_str())
3331 || is_prefix_of(".fini_array.", this->section_name_
.c_str()))
3336 unsigned long prio
= strtoul((this->section_name_
.c_str()
3337 + (is_ctors
? 7 : 12)),
3342 return 65535 - prio
;
3347 // Return true if this an input file whose base name matches
3348 // FILE_NAME. The base name must have an extension of ".o", and
3349 // must be exactly FILE_NAME.o or FILE_NAME, one character, ".o".
3350 // This is to match crtbegin.o as well as crtbeginS.o without
3351 // getting confused by other possibilities. Overall matching the
3352 // file name this way is a dreadful hack, but the GNU linker does it
3353 // in order to better support gcc, and we need to be compatible.
3355 match_file_name(const char* file_name
) const
3357 if (this->input_section_
.is_output_section_data())
3359 return Layout::match_file_name(this->input_section_
.relobj(), file_name
);
3362 // Returns 1 if THIS should appear before S in section order, -1 if S
3363 // appears before THIS and 0 if they are not comparable.
3365 compare_section_ordering(const Input_section_sort_entry
& s
) const
3367 unsigned int this_secn_index
= this->input_section_
.section_order_index();
3368 unsigned int s_secn_index
= s
.input_section().section_order_index();
3369 if (this_secn_index
> 0 && s_secn_index
> 0)
3371 if (this_secn_index
< s_secn_index
)
3373 else if (this_secn_index
> s_secn_index
)
3380 // The Input_section we are sorting.
3381 Input_section input_section_
;
3382 // The index of this Input_section in the original list.
3383 unsigned int index_
;
3384 // The section name if there is one.
3385 std::string section_name_
;
3388 // Return true if S1 should come before S2 in the output section.
3391 Output_section::Input_section_sort_compare::operator()(
3392 const Output_section::Input_section_sort_entry
& s1
,
3393 const Output_section::Input_section_sort_entry
& s2
) const
3395 // crtbegin.o must come first.
3396 bool s1_begin
= s1
.match_file_name("crtbegin");
3397 bool s2_begin
= s2
.match_file_name("crtbegin");
3398 if (s1_begin
|| s2_begin
)
3404 return s1
.index() < s2
.index();
3407 // crtend.o must come last.
3408 bool s1_end
= s1
.match_file_name("crtend");
3409 bool s2_end
= s2
.match_file_name("crtend");
3410 if (s1_end
|| s2_end
)
3416 return s1
.index() < s2
.index();
3419 // A section with a priority follows a section without a priority.
3420 bool s1_has_priority
= s1
.has_priority();
3421 bool s2_has_priority
= s2
.has_priority();
3422 if (s1_has_priority
&& !s2_has_priority
)
3424 if (!s1_has_priority
&& s2_has_priority
)
3427 // Check if a section order exists for these sections through a section
3428 // ordering file. If sequence_num is 0, an order does not exist.
3429 int sequence_num
= s1
.compare_section_ordering(s2
);
3430 if (sequence_num
!= 0)
3431 return sequence_num
== 1;
3433 // Otherwise we sort by name.
3434 int compare
= s1
.section_name().compare(s2
.section_name());
3438 // Otherwise we keep the input order.
3439 return s1
.index() < s2
.index();
3442 // Return true if S1 should come before S2 in an .init_array or .fini_array
3446 Output_section::Input_section_sort_init_fini_compare::operator()(
3447 const Output_section::Input_section_sort_entry
& s1
,
3448 const Output_section::Input_section_sort_entry
& s2
) const
3450 // A section without a priority follows a section with a priority.
3451 // This is the reverse of .ctors and .dtors sections.
3452 bool s1_has_priority
= s1
.has_priority();
3453 bool s2_has_priority
= s2
.has_priority();
3454 if (s1_has_priority
&& !s2_has_priority
)
3456 if (!s1_has_priority
&& s2_has_priority
)
3459 // .ctors and .dtors sections without priority come after
3460 // .init_array and .fini_array sections without priority.
3461 if (!s1_has_priority
3462 && (s1
.section_name() == ".ctors" || s1
.section_name() == ".dtors")
3463 && s1
.section_name() != s2
.section_name())
3465 if (!s2_has_priority
3466 && (s2
.section_name() == ".ctors" || s2
.section_name() == ".dtors")
3467 && s2
.section_name() != s1
.section_name())
3470 // Sort by priority if we can.
3471 if (s1_has_priority
)
3473 unsigned int s1_prio
= s1
.get_priority();
3474 unsigned int s2_prio
= s2
.get_priority();
3475 if (s1_prio
< s2_prio
)
3477 else if (s1_prio
> s2_prio
)
3481 // Check if a section order exists for these sections through a section
3482 // ordering file. If sequence_num is 0, an order does not exist.
3483 int sequence_num
= s1
.compare_section_ordering(s2
);
3484 if (sequence_num
!= 0)
3485 return sequence_num
== 1;
3487 // Otherwise we sort by name.
3488 int compare
= s1
.section_name().compare(s2
.section_name());
3492 // Otherwise we keep the input order.
3493 return s1
.index() < s2
.index();
3496 // Return true if S1 should come before S2. Sections that do not match
3497 // any pattern in the section ordering file are placed ahead of the sections
3498 // that match some pattern.
3501 Output_section::Input_section_sort_section_order_index_compare::operator()(
3502 const Output_section::Input_section_sort_entry
& s1
,
3503 const Output_section::Input_section_sort_entry
& s2
) const
3505 unsigned int s1_secn_index
= s1
.input_section().section_order_index();
3506 unsigned int s2_secn_index
= s2
.input_section().section_order_index();
3508 // Keep input order if section ordering cannot determine order.
3509 if (s1_secn_index
== s2_secn_index
)
3510 return s1
.index() < s2
.index();
3512 return s1_secn_index
< s2_secn_index
;
3515 // Return true if S1 should come before S2. This is the sort comparison
3516 // function for .text to sort sections with prefixes
3517 // .text.{unlikely,exit,startup,hot} before other sections.
3520 Output_section::Input_section_sort_section_prefix_special_ordering_compare
3522 const Output_section::Input_section_sort_entry
& s1
,
3523 const Output_section::Input_section_sort_entry
& s2
) const
3525 // Some input section names have special ordering requirements.
3526 int o1
= Layout::special_ordering_of_input_section(s1
.section_name().c_str());
3527 int o2
= Layout::special_ordering_of_input_section(s2
.section_name().c_str());
3538 // Keep input order otherwise.
3539 return s1
.index() < s2
.index();
3542 // Return true if S1 should come before S2. This is the sort comparison
3543 // function for sections to sort them by name.
3546 Output_section::Input_section_sort_section_name_compare
3548 const Output_section::Input_section_sort_entry
& s1
,
3549 const Output_section::Input_section_sort_entry
& s2
) const
3552 int compare
= s1
.section_name().compare(s2
.section_name());
3556 // Keep input order otherwise.
3557 return s1
.index() < s2
.index();
3560 // This updates the section order index of input sections according to the
3561 // the order specified in the mapping from Section id to order index.
3564 Output_section::update_section_layout(
3565 const Section_layout_order
* order_map
)
3567 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3568 p
!= this->input_sections_
.end();
3571 if (p
->is_input_section()
3572 || p
->is_relaxed_input_section())
3574 Relobj
* obj
= (p
->is_input_section()
3576 : p
->relaxed_input_section()->relobj());
3577 unsigned int shndx
= p
->shndx();
3578 Section_layout_order::const_iterator it
3579 = order_map
->find(Section_id(obj
, shndx
));
3580 if (it
== order_map
->end())
3582 unsigned int section_order_index
= it
->second
;
3583 if (section_order_index
!= 0)
3585 p
->set_section_order_index(section_order_index
);
3586 this->set_input_section_order_specified();
3592 // Sort the input sections attached to an output section.
3595 Output_section::sort_attached_input_sections()
3597 if (this->attached_input_sections_are_sorted_
)
3600 if (this->checkpoint_
!= NULL
3601 && !this->checkpoint_
->input_sections_saved())
3602 this->checkpoint_
->save_input_sections();
3604 // The only thing we know about an input section is the object and
3605 // the section index. We need the section name. Recomputing this
3606 // is slow but this is an unusual case. If this becomes a speed
3607 // problem we can cache the names as required in Layout::layout.
3609 // We start by building a larger vector holding a copy of each
3610 // Input_section, plus its current index in the list and its name.
3611 std::vector
<Input_section_sort_entry
> sort_list
;
3614 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3615 p
!= this->input_sections_
.end();
3617 sort_list
.push_back(Input_section_sort_entry(*p
, i
,
3618 this->must_sort_attached_input_sections(),
3621 // Sort the input sections.
3622 if (this->must_sort_attached_input_sections())
3624 if (this->type() == elfcpp::SHT_PREINIT_ARRAY
3625 || this->type() == elfcpp::SHT_INIT_ARRAY
3626 || this->type() == elfcpp::SHT_FINI_ARRAY
)
3627 std::sort(sort_list
.begin(), sort_list
.end(),
3628 Input_section_sort_init_fini_compare());
3629 else if (strcmp(parameters
->options().sort_section(), "name") == 0)
3630 std::sort(sort_list
.begin(), sort_list
.end(),
3631 Input_section_sort_section_name_compare());
3632 else if (strcmp(this->name(), ".text") == 0)
3633 std::sort(sort_list
.begin(), sort_list
.end(),
3634 Input_section_sort_section_prefix_special_ordering_compare());
3636 std::sort(sort_list
.begin(), sort_list
.end(),
3637 Input_section_sort_compare());
3641 gold_assert(this->input_section_order_specified());
3642 std::sort(sort_list
.begin(), sort_list
.end(),
3643 Input_section_sort_section_order_index_compare());
3646 // Copy the sorted input sections back to our list.
3647 this->input_sections_
.clear();
3648 for (std::vector
<Input_section_sort_entry
>::iterator p
= sort_list
.begin();
3649 p
!= sort_list
.end();
3651 this->input_sections_
.push_back(p
->input_section());
3654 // Remember that we sorted the input sections, since we might get
3656 this->attached_input_sections_are_sorted_
= true;
3659 // Write the section header to *OSHDR.
3661 template<int size
, bool big_endian
>
3663 Output_section::write_header(const Layout
* layout
,
3664 const Stringpool
* secnamepool
,
3665 elfcpp::Shdr_write
<size
, big_endian
>* oshdr
) const
3667 oshdr
->put_sh_name(secnamepool
->get_offset(this->name_
));
3668 oshdr
->put_sh_type(this->type_
);
3670 elfcpp::Elf_Xword flags
= this->flags_
;
3671 if (this->info_section_
!= NULL
&& this->info_uses_section_index_
)
3672 flags
|= elfcpp::SHF_INFO_LINK
;
3673 oshdr
->put_sh_flags(flags
);
3675 oshdr
->put_sh_addr(this->address());
3676 oshdr
->put_sh_offset(this->offset());
3677 oshdr
->put_sh_size(this->data_size());
3678 if (this->link_section_
!= NULL
)
3679 oshdr
->put_sh_link(this->link_section_
->out_shndx());
3680 else if (this->should_link_to_symtab_
)
3681 oshdr
->put_sh_link(layout
->symtab_section_shndx());
3682 else if (this->should_link_to_dynsym_
)
3683 oshdr
->put_sh_link(layout
->dynsym_section()->out_shndx());
3685 oshdr
->put_sh_link(this->link_
);
3687 elfcpp::Elf_Word info
;
3688 if (this->info_section_
!= NULL
)
3690 if (this->info_uses_section_index_
)
3691 info
= this->info_section_
->out_shndx();
3693 info
= this->info_section_
->symtab_index();
3695 else if (this->info_symndx_
!= NULL
)
3696 info
= this->info_symndx_
->symtab_index();
3699 oshdr
->put_sh_info(info
);
3701 oshdr
->put_sh_addralign(this->addralign_
);
3702 oshdr
->put_sh_entsize(this->entsize_
);
3705 // Write out the data. For input sections the data is written out by
3706 // Object::relocate, but we have to handle Output_section_data objects
3710 Output_section::do_write(Output_file
* of
)
3712 gold_assert(!this->requires_postprocessing());
3714 // If the target performs relaxation, we delay filler generation until now.
3715 gold_assert(!this->generate_code_fills_at_write_
|| this->fills_
.empty());
3717 off_t output_section_file_offset
= this->offset();
3718 for (Fill_list::iterator p
= this->fills_
.begin();
3719 p
!= this->fills_
.end();
3722 std::string
fill_data(parameters
->target().code_fill(p
->length()));
3723 of
->write(output_section_file_offset
+ p
->section_offset(),
3724 fill_data
.data(), fill_data
.size());
3727 off_t off
= this->offset() + this->first_input_offset_
;
3728 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3729 p
!= this->input_sections_
.end();
3732 off_t aligned_off
= align_address(off
, p
->addralign());
3733 if (this->generate_code_fills_at_write_
&& (off
!= aligned_off
))
3735 size_t fill_len
= aligned_off
- off
;
3736 std::string
fill_data(parameters
->target().code_fill(fill_len
));
3737 of
->write(off
, fill_data
.data(), fill_data
.size());
3741 off
= aligned_off
+ p
->data_size();
3744 // For incremental links, fill in unused chunks in debug sections
3745 // with dummy compilation unit headers.
3746 if (this->free_space_fill_
!= NULL
)
3748 for (Free_list::Const_iterator p
= this->free_list_
.begin();
3749 p
!= this->free_list_
.end();
3752 off_t off
= p
->start_
;
3753 size_t len
= p
->end_
- off
;
3754 this->free_space_fill_
->write(of
, this->offset() + off
, len
);
3756 if (this->patch_space_
> 0)
3758 off_t off
= this->current_data_size_for_child() - this->patch_space_
;
3759 this->free_space_fill_
->write(of
, this->offset() + off
,
3760 this->patch_space_
);
3765 // If a section requires postprocessing, create the buffer to use.
3768 Output_section::create_postprocessing_buffer()
3770 gold_assert(this->requires_postprocessing());
3772 if (this->postprocessing_buffer_
!= NULL
)
3775 if (!this->input_sections_
.empty())
3777 off_t off
= this->first_input_offset_
;
3778 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3779 p
!= this->input_sections_
.end();
3782 off
= align_address(off
, p
->addralign());
3783 p
->finalize_data_size();
3784 off
+= p
->data_size();
3786 this->set_current_data_size_for_child(off
);
3789 off_t buffer_size
= this->current_data_size_for_child();
3790 this->postprocessing_buffer_
= new unsigned char[buffer_size
];
3793 // Write all the data of an Output_section into the postprocessing
3794 // buffer. This is used for sections which require postprocessing,
3795 // such as compression. Input sections are handled by
3796 // Object::Relocate.
3799 Output_section::write_to_postprocessing_buffer()
3801 gold_assert(this->requires_postprocessing());
3803 // If the target performs relaxation, we delay filler generation until now.
3804 gold_assert(!this->generate_code_fills_at_write_
|| this->fills_
.empty());
3806 unsigned char* buffer
= this->postprocessing_buffer();
3807 for (Fill_list::iterator p
= this->fills_
.begin();
3808 p
!= this->fills_
.end();
3811 std::string
fill_data(parameters
->target().code_fill(p
->length()));
3812 memcpy(buffer
+ p
->section_offset(), fill_data
.data(),
3816 off_t off
= this->first_input_offset_
;
3817 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3818 p
!= this->input_sections_
.end();
3821 off_t aligned_off
= align_address(off
, p
->addralign());
3822 if (this->generate_code_fills_at_write_
&& (off
!= aligned_off
))
3824 size_t fill_len
= aligned_off
- off
;
3825 std::string
fill_data(parameters
->target().code_fill(fill_len
));
3826 memcpy(buffer
+ off
, fill_data
.data(), fill_data
.size());
3829 p
->write_to_buffer(buffer
+ aligned_off
);
3830 off
= aligned_off
+ p
->data_size();
3834 // Get the input sections for linker script processing. We leave
3835 // behind the Output_section_data entries. Note that this may be
3836 // slightly incorrect for merge sections. We will leave them behind,
3837 // but it is possible that the script says that they should follow
3838 // some other input sections, as in:
3839 // .rodata { *(.rodata) *(.rodata.cst*) }
3840 // For that matter, we don't handle this correctly:
3841 // .rodata { foo.o(.rodata.cst*) *(.rodata.cst*) }
3842 // With luck this will never matter.
3845 Output_section::get_input_sections(
3847 const std::string
& fill
,
3848 std::list
<Input_section
>* input_sections
)
3850 if (this->checkpoint_
!= NULL
3851 && !this->checkpoint_
->input_sections_saved())
3852 this->checkpoint_
->save_input_sections();
3854 // Invalidate fast look-up maps.
3855 this->lookup_maps_
->invalidate();
3857 uint64_t orig_address
= address
;
3859 address
= align_address(address
, this->addralign());
3861 Input_section_list remaining
;
3862 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3863 p
!= this->input_sections_
.end();
3866 if (p
->is_input_section()
3867 || p
->is_relaxed_input_section()
3868 || p
->is_merge_section())
3869 input_sections
->push_back(*p
);
3872 uint64_t aligned_address
= align_address(address
, p
->addralign());
3873 if (aligned_address
!= address
&& !fill
.empty())
3875 section_size_type length
=
3876 convert_to_section_size_type(aligned_address
- address
);
3877 std::string this_fill
;
3878 this_fill
.reserve(length
);
3879 while (this_fill
.length() + fill
.length() <= length
)
3881 if (this_fill
.length() < length
)
3882 this_fill
.append(fill
, 0, length
- this_fill
.length());
3884 Output_section_data
* posd
= new Output_data_const(this_fill
, 0);
3885 remaining
.push_back(Input_section(posd
));
3887 address
= aligned_address
;
3889 remaining
.push_back(*p
);
3891 p
->finalize_data_size();
3892 address
+= p
->data_size();
3896 this->input_sections_
.swap(remaining
);
3897 this->first_input_offset_
= 0;
3899 uint64_t data_size
= address
- orig_address
;
3900 this->set_current_data_size_for_child(data_size
);
3904 // Add a script input section. SIS is an Output_section::Input_section,
3905 // which can be either a plain input section or a special input section like
3906 // a relaxed input section. For a special input section, its size must be
3910 Output_section::add_script_input_section(const Input_section
& sis
)
3912 uint64_t data_size
= sis
.data_size();
3913 uint64_t addralign
= sis
.addralign();
3914 if (addralign
> this->addralign_
)
3915 this->addralign_
= addralign
;
3917 off_t offset_in_section
= this->current_data_size_for_child();
3918 off_t aligned_offset_in_section
= align_address(offset_in_section
,
3921 this->set_current_data_size_for_child(aligned_offset_in_section
3924 this->input_sections_
.push_back(sis
);
3926 // Update fast lookup maps if necessary.
3927 if (this->lookup_maps_
->is_valid())
3929 if (sis
.is_relaxed_input_section())
3931 Output_relaxed_input_section
* poris
= sis
.relaxed_input_section();
3932 this->lookup_maps_
->add_relaxed_input_section(poris
->relobj(),
3933 poris
->shndx(), poris
);
3938 // Save states for relaxation.
3941 Output_section::save_states()
3943 gold_assert(this->checkpoint_
== NULL
);
3944 Checkpoint_output_section
* checkpoint
=
3945 new Checkpoint_output_section(this->addralign_
, this->flags_
,
3946 this->input_sections_
,
3947 this->first_input_offset_
,
3948 this->attached_input_sections_are_sorted_
);
3949 this->checkpoint_
= checkpoint
;
3950 gold_assert(this->fills_
.empty());
3954 Output_section::discard_states()
3956 gold_assert(this->checkpoint_
!= NULL
);
3957 delete this->checkpoint_
;
3958 this->checkpoint_
= NULL
;
3959 gold_assert(this->fills_
.empty());
3961 // Simply invalidate the fast lookup maps since we do not keep
3963 this->lookup_maps_
->invalidate();
3967 Output_section::restore_states()
3969 gold_assert(this->checkpoint_
!= NULL
);
3970 Checkpoint_output_section
* checkpoint
= this->checkpoint_
;
3972 this->addralign_
= checkpoint
->addralign();
3973 this->flags_
= checkpoint
->flags();
3974 this->first_input_offset_
= checkpoint
->first_input_offset();
3976 if (!checkpoint
->input_sections_saved())
3978 // If we have not copied the input sections, just resize it.
3979 size_t old_size
= checkpoint
->input_sections_size();
3980 gold_assert(this->input_sections_
.size() >= old_size
);
3981 this->input_sections_
.resize(old_size
);
3985 // We need to copy the whole list. This is not efficient for
3986 // extremely large output with hundreads of thousands of input
3987 // objects. We may need to re-think how we should pass sections
3989 this->input_sections_
= *checkpoint
->input_sections();
3992 this->attached_input_sections_are_sorted_
=
3993 checkpoint
->attached_input_sections_are_sorted();
3995 // Simply invalidate the fast lookup maps since we do not keep
3997 this->lookup_maps_
->invalidate();
4000 // Update the section offsets of input sections in this. This is required if
4001 // relaxation causes some input sections to change sizes.
4004 Output_section::adjust_section_offsets()
4006 if (!this->section_offsets_need_adjustment_
)
4010 for (Input_section_list::iterator p
= this->input_sections_
.begin();
4011 p
!= this->input_sections_
.end();
4014 off
= align_address(off
, p
->addralign());
4015 if (p
->is_input_section())
4016 p
->relobj()->set_section_offset(p
->shndx(), off
);
4017 off
+= p
->data_size();
4020 this->section_offsets_need_adjustment_
= false;
4023 // Print to the map file.
4026 Output_section::do_print_to_mapfile(Mapfile
* mapfile
) const
4028 mapfile
->print_output_section(this);
4030 for (Input_section_list::const_iterator p
= this->input_sections_
.begin();
4031 p
!= this->input_sections_
.end();
4033 p
->print_to_mapfile(mapfile
);
4036 // Print stats for merge sections to stderr.
4039 Output_section::print_merge_stats()
4041 Input_section_list::iterator p
;
4042 for (p
= this->input_sections_
.begin();
4043 p
!= this->input_sections_
.end();
4045 p
->print_merge_stats(this->name_
);
4048 // Set a fixed layout for the section. Used for incremental update links.
4051 Output_section::set_fixed_layout(uint64_t sh_addr
, off_t sh_offset
,
4052 off_t sh_size
, uint64_t sh_addralign
)
4054 this->addralign_
= sh_addralign
;
4055 this->set_current_data_size(sh_size
);
4056 if ((this->flags_
& elfcpp::SHF_ALLOC
) != 0)
4057 this->set_address(sh_addr
);
4058 this->set_file_offset(sh_offset
);
4059 this->finalize_data_size();
4060 this->free_list_
.init(sh_size
, false);
4061 this->has_fixed_layout_
= true;
4064 // Reserve space within the fixed layout for the section. Used for
4065 // incremental update links.
4068 Output_section::reserve(uint64_t sh_offset
, uint64_t sh_size
)
4070 this->free_list_
.remove(sh_offset
, sh_offset
+ sh_size
);
4073 // Allocate space from the free list for the section. Used for
4074 // incremental update links.
4077 Output_section::allocate(off_t len
, uint64_t addralign
)
4079 return this->free_list_
.allocate(len
, addralign
, 0);
4082 // Output segment methods.
4084 Output_segment::Output_segment(elfcpp::Elf_Word type
, elfcpp::Elf_Word flags
)
4094 is_max_align_known_(false),
4095 are_addresses_set_(false),
4096 is_large_data_segment_(false),
4097 is_unique_segment_(false)
4099 // The ELF ABI specifies that a PT_TLS segment always has PF_R as
4101 if (type
== elfcpp::PT_TLS
)
4102 this->flags_
= elfcpp::PF_R
;
4105 // Add an Output_section to a PT_LOAD Output_segment.
4108 Output_segment::add_output_section_to_load(Layout
* layout
,
4110 elfcpp::Elf_Word seg_flags
)
4112 gold_assert(this->type() == elfcpp::PT_LOAD
);
4113 gold_assert((os
->flags() & elfcpp::SHF_ALLOC
) != 0);
4114 gold_assert(!this->is_max_align_known_
);
4115 gold_assert(os
->is_large_data_section() == this->is_large_data_segment());
4117 this->update_flags_for_output_section(seg_flags
);
4119 // We don't want to change the ordering if we have a linker script
4120 // with a SECTIONS clause.
4121 Output_section_order order
= os
->order();
4122 if (layout
->script_options()->saw_sections_clause())
4123 order
= static_cast<Output_section_order
>(0);
4125 gold_assert(order
!= ORDER_INVALID
);
4127 this->output_lists_
[order
].push_back(os
);
4130 // Add an Output_section to a non-PT_LOAD Output_segment.
4133 Output_segment::add_output_section_to_nonload(Output_section
* os
,
4134 elfcpp::Elf_Word seg_flags
)
4136 gold_assert(this->type() != elfcpp::PT_LOAD
);
4137 gold_assert((os
->flags() & elfcpp::SHF_ALLOC
) != 0);
4138 gold_assert(!this->is_max_align_known_
);
4140 this->update_flags_for_output_section(seg_flags
);
4142 this->output_lists_
[0].push_back(os
);
4145 // Remove an Output_section from this segment. It is an error if it
4149 Output_segment::remove_output_section(Output_section
* os
)
4151 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4153 Output_data_list
* pdl
= &this->output_lists_
[i
];
4154 for (Output_data_list::iterator p
= pdl
->begin(); p
!= pdl
->end(); ++p
)
4166 // Add an Output_data (which need not be an Output_section) to the
4167 // start of a segment.
4170 Output_segment::add_initial_output_data(Output_data
* od
)
4172 gold_assert(!this->is_max_align_known_
);
4173 Output_data_list::iterator p
= this->output_lists_
[0].begin();
4174 this->output_lists_
[0].insert(p
, od
);
4177 // Return true if this segment has any sections which hold actual
4178 // data, rather than being a BSS section.
4181 Output_segment::has_any_data_sections() const
4183 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4185 const Output_data_list
* pdl
= &this->output_lists_
[i
];
4186 for (Output_data_list::const_iterator p
= pdl
->begin();
4190 if (!(*p
)->is_section())
4192 if ((*p
)->output_section()->type() != elfcpp::SHT_NOBITS
)
4199 // Return whether the first data section (not counting TLS sections)
4200 // is a relro section.
4203 Output_segment::is_first_section_relro() const
4205 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4207 if (i
== static_cast<int>(ORDER_TLS_BSS
))
4209 const Output_data_list
* pdl
= &this->output_lists_
[i
];
4212 Output_data
* p
= pdl
->front();
4213 return p
->is_section() && p
->output_section()->is_relro();
4219 // Return the maximum alignment of the Output_data in Output_segment.
4222 Output_segment::maximum_alignment()
4224 if (!this->is_max_align_known_
)
4226 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4228 const Output_data_list
* pdl
= &this->output_lists_
[i
];
4229 uint64_t addralign
= Output_segment::maximum_alignment_list(pdl
);
4230 if (addralign
> this->max_align_
)
4231 this->max_align_
= addralign
;
4233 this->is_max_align_known_
= true;
4236 return this->max_align_
;
4239 // Return the maximum alignment of a list of Output_data.
4242 Output_segment::maximum_alignment_list(const Output_data_list
* pdl
)
4245 for (Output_data_list::const_iterator p
= pdl
->begin();
4249 uint64_t addralign
= (*p
)->addralign();
4250 if (addralign
> ret
)
4256 // Return whether this segment has any dynamic relocs.
4259 Output_segment::has_dynamic_reloc() const
4261 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4262 if (this->has_dynamic_reloc_list(&this->output_lists_
[i
]))
4267 // Return whether this Output_data_list has any dynamic relocs.
4270 Output_segment::has_dynamic_reloc_list(const Output_data_list
* pdl
) const
4272 for (Output_data_list::const_iterator p
= pdl
->begin();
4275 if ((*p
)->has_dynamic_reloc())
4280 // Set the section addresses for an Output_segment. If RESET is true,
4281 // reset the addresses first. ADDR is the address and *POFF is the
4282 // file offset. Set the section indexes starting with *PSHNDX.
4283 // INCREASE_RELRO is the size of the portion of the first non-relro
4284 // section that should be included in the PT_GNU_RELRO segment.
4285 // If this segment has relro sections, and has been aligned for
4286 // that purpose, set *HAS_RELRO to TRUE. Return the address of
4287 // the immediately following segment. Update *HAS_RELRO, *POFF,
4291 Output_segment::set_section_addresses(const Target
* target
,
4292 Layout
* layout
, bool reset
,
4294 unsigned int* increase_relro
,
4297 unsigned int* pshndx
)
4299 gold_assert(this->type_
== elfcpp::PT_LOAD
);
4301 uint64_t last_relro_pad
= 0;
4302 off_t orig_off
= *poff
;
4304 bool in_tls
= false;
4306 // If we have relro sections, we need to pad forward now so that the
4307 // relro sections plus INCREASE_RELRO end on an abi page boundary.
4308 if (parameters
->options().relro()
4309 && this->is_first_section_relro()
4310 && (!this->are_addresses_set_
|| reset
))
4312 uint64_t relro_size
= 0;
4314 uint64_t max_align
= 0;
4315 for (int i
= 0; i
<= static_cast<int>(ORDER_RELRO_LAST
); ++i
)
4317 Output_data_list
* pdl
= &this->output_lists_
[i
];
4318 Output_data_list::iterator p
;
4319 for (p
= pdl
->begin(); p
!= pdl
->end(); ++p
)
4321 if (!(*p
)->is_section())
4323 uint64_t align
= (*p
)->addralign();
4324 if (align
> max_align
)
4326 if ((*p
)->is_section_flag_set(elfcpp::SHF_TLS
))
4330 // Align the first non-TLS section to the alignment
4331 // of the TLS segment.
4335 // Ignore the size of the .tbss section.
4336 if ((*p
)->is_section_flag_set(elfcpp::SHF_TLS
)
4337 && (*p
)->is_section_type(elfcpp::SHT_NOBITS
))
4339 relro_size
= align_address(relro_size
, align
);
4340 if ((*p
)->is_address_valid())
4341 relro_size
+= (*p
)->data_size();
4344 // FIXME: This could be faster.
4345 (*p
)->set_address_and_file_offset(relro_size
,
4347 relro_size
+= (*p
)->data_size();
4348 (*p
)->reset_address_and_file_offset();
4351 if (p
!= pdl
->end())
4354 relro_size
+= *increase_relro
;
4355 // Pad the total relro size to a multiple of the maximum
4356 // section alignment seen.
4357 uint64_t aligned_size
= align_address(relro_size
, max_align
);
4358 // Note the amount of padding added after the last relro section.
4359 last_relro_pad
= aligned_size
- relro_size
;
4362 uint64_t page_align
= parameters
->target().abi_pagesize();
4364 // Align to offset N such that (N + RELRO_SIZE) % PAGE_ALIGN == 0.
4365 uint64_t desired_align
= page_align
- (aligned_size
% page_align
);
4366 if (desired_align
< off
% page_align
)
4368 off
+= desired_align
- off
% page_align
;
4369 addr
+= off
- orig_off
;
4374 if (!reset
&& this->are_addresses_set_
)
4376 gold_assert(this->paddr_
== addr
);
4377 addr
= this->vaddr_
;
4381 this->vaddr_
= addr
;
4382 this->paddr_
= addr
;
4383 this->are_addresses_set_
= true;
4388 this->offset_
= orig_off
;
4392 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4394 if (i
== static_cast<int>(ORDER_RELRO_LAST
))
4396 *poff
+= last_relro_pad
;
4397 addr
+= last_relro_pad
;
4398 if (this->output_lists_
[i
].empty())
4400 // If there is nothing in the ORDER_RELRO_LAST list,
4401 // the padding will occur at the end of the relro
4402 // segment, and we need to add it to *INCREASE_RELRO.
4403 *increase_relro
+= last_relro_pad
;
4406 addr
= this->set_section_list_addresses(layout
, reset
,
4407 &this->output_lists_
[i
],
4408 addr
, poff
, pshndx
, &in_tls
);
4409 if (i
< static_cast<int>(ORDER_SMALL_BSS
))
4411 this->filesz_
= *poff
- orig_off
;
4418 // If the last section was a TLS section, align upward to the
4419 // alignment of the TLS segment, so that the overall size of the TLS
4420 // segment is aligned.
4423 uint64_t segment_align
= layout
->tls_segment()->maximum_alignment();
4424 *poff
= align_address(*poff
, segment_align
);
4427 this->memsz_
= *poff
- orig_off
;
4429 // Ignore the file offset adjustments made by the BSS Output_data
4433 // If code segments must contain only code, and this code segment is
4434 // page-aligned in the file, then fill it out to a whole page with
4435 // code fill (the tail of the segment will not be within any section).
4436 // Thus the entire code segment can be mapped from the file as whole
4437 // pages and that mapping will contain only valid instructions.
4438 if (target
->isolate_execinstr() && (this->flags() & elfcpp::PF_X
) != 0)
4440 uint64_t abi_pagesize
= target
->abi_pagesize();
4441 if (orig_off
% abi_pagesize
== 0 && off
% abi_pagesize
!= 0)
4443 size_t fill_size
= abi_pagesize
- (off
% abi_pagesize
);
4445 std::string fill_data
;
4446 if (target
->has_code_fill())
4447 fill_data
= target
->code_fill(fill_size
);
4449 fill_data
.resize(fill_size
); // Zero fill.
4451 Output_data_const
* fill
= new Output_data_const(fill_data
, 0);
4452 fill
->set_address(this->vaddr_
+ this->memsz_
);
4453 fill
->set_file_offset(off
);
4454 layout
->add_relax_output(fill
);
4457 gold_assert(off
% abi_pagesize
== 0);
4459 gold_assert(ret
% abi_pagesize
== 0);
4461 gold_assert((uint64_t) this->filesz_
== this->memsz_
);
4462 this->memsz_
= this->filesz_
+= fill_size
;
4471 // Set the addresses and file offsets in a list of Output_data
4475 Output_segment::set_section_list_addresses(Layout
* layout
, bool reset
,
4476 Output_data_list
* pdl
,
4477 uint64_t addr
, off_t
* poff
,
4478 unsigned int* pshndx
,
4481 off_t startoff
= *poff
;
4482 // For incremental updates, we may allocate non-fixed sections from
4483 // free space in the file. This keeps track of the high-water mark.
4484 off_t maxoff
= startoff
;
4486 off_t off
= startoff
;
4487 for (Output_data_list::iterator p
= pdl
->begin();
4492 (*p
)->reset_address_and_file_offset();
4494 // When doing an incremental update or when using a linker script,
4495 // the section will most likely already have an address.
4496 if (!(*p
)->is_address_valid())
4498 uint64_t align
= (*p
)->addralign();
4500 if ((*p
)->is_section_flag_set(elfcpp::SHF_TLS
))
4502 // Give the first TLS section the alignment of the
4503 // entire TLS segment. Otherwise the TLS segment as a
4504 // whole may be misaligned.
4507 Output_segment
* tls_segment
= layout
->tls_segment();
4508 gold_assert(tls_segment
!= NULL
);
4509 uint64_t segment_align
= tls_segment
->maximum_alignment();
4510 gold_assert(segment_align
>= align
);
4511 align
= segment_align
;
4518 // If this is the first section after the TLS segment,
4519 // align it to at least the alignment of the TLS
4520 // segment, so that the size of the overall TLS segment
4524 uint64_t segment_align
=
4525 layout
->tls_segment()->maximum_alignment();
4526 if (segment_align
> align
)
4527 align
= segment_align
;
4533 if (!parameters
->incremental_update())
4535 off
= align_address(off
, align
);
4536 (*p
)->set_address_and_file_offset(addr
+ (off
- startoff
), off
);
4540 // Incremental update: allocate file space from free list.
4541 (*p
)->pre_finalize_data_size();
4542 off_t current_size
= (*p
)->current_data_size();
4543 off
= layout
->allocate(current_size
, align
, startoff
);
4546 gold_assert((*p
)->output_section() != NULL
);
4547 gold_fallback(_("out of patch space for section %s; "
4548 "relink with --incremental-full"),
4549 (*p
)->output_section()->name());
4551 (*p
)->set_address_and_file_offset(addr
+ (off
- startoff
), off
);
4552 if ((*p
)->data_size() > current_size
)
4554 gold_assert((*p
)->output_section() != NULL
);
4555 gold_fallback(_("%s: section changed size; "
4556 "relink with --incremental-full"),
4557 (*p
)->output_section()->name());
4561 else if (parameters
->incremental_update())
4563 // For incremental updates, use the fixed offset for the
4564 // high-water mark computation.
4565 off
= (*p
)->offset();
4569 // The script may have inserted a skip forward, but it
4570 // better not have moved backward.
4571 if ((*p
)->address() >= addr
+ (off
- startoff
))
4572 off
+= (*p
)->address() - (addr
+ (off
- startoff
));
4575 if (!layout
->script_options()->saw_sections_clause())
4579 Output_section
* os
= (*p
)->output_section();
4581 // Cast to unsigned long long to avoid format warnings.
4582 unsigned long long previous_dot
=
4583 static_cast<unsigned long long>(addr
+ (off
- startoff
));
4584 unsigned long long dot
=
4585 static_cast<unsigned long long>((*p
)->address());
4588 gold_error(_("dot moves backward in linker script "
4589 "from 0x%llx to 0x%llx"), previous_dot
, dot
);
4591 gold_error(_("address of section '%s' moves backward "
4592 "from 0x%llx to 0x%llx"),
4593 os
->name(), previous_dot
, dot
);
4596 (*p
)->set_file_offset(off
);
4597 (*p
)->finalize_data_size();
4600 if (parameters
->incremental_update())
4601 gold_debug(DEBUG_INCREMENTAL
,
4602 "set_section_list_addresses: %08lx %08lx %s",
4603 static_cast<long>(off
),
4604 static_cast<long>((*p
)->data_size()),
4605 ((*p
)->output_section() != NULL
4606 ? (*p
)->output_section()->name() : "(special)"));
4608 // We want to ignore the size of a SHF_TLS SHT_NOBITS
4609 // section. Such a section does not affect the size of a
4611 if (!(*p
)->is_section_flag_set(elfcpp::SHF_TLS
)
4612 || !(*p
)->is_section_type(elfcpp::SHT_NOBITS
))
4613 off
+= (*p
)->data_size();
4618 if ((*p
)->is_section())
4620 (*p
)->set_out_shndx(*pshndx
);
4626 return addr
+ (maxoff
- startoff
);
4629 // For a non-PT_LOAD segment, set the offset from the sections, if
4630 // any. Add INCREASE to the file size and the memory size.
4633 Output_segment::set_offset(unsigned int increase
)
4635 gold_assert(this->type_
!= elfcpp::PT_LOAD
);
4637 gold_assert(!this->are_addresses_set_
);
4639 // A non-load section only uses output_lists_[0].
4641 Output_data_list
* pdl
= &this->output_lists_
[0];
4645 gold_assert(increase
== 0);
4648 this->are_addresses_set_
= true;
4650 this->min_p_align_
= 0;
4656 // Find the first and last section by address.
4657 const Output_data
* first
= NULL
;
4658 const Output_data
* last_data
= NULL
;
4659 const Output_data
* last_bss
= NULL
;
4660 for (Output_data_list::const_iterator p
= pdl
->begin();
4665 || (*p
)->address() < first
->address()
4666 || ((*p
)->address() == first
->address()
4667 && (*p
)->data_size() < first
->data_size()))
4669 const Output_data
** plast
;
4670 if ((*p
)->is_section()
4671 && (*p
)->output_section()->type() == elfcpp::SHT_NOBITS
)
4676 || (*p
)->address() > (*plast
)->address()
4677 || ((*p
)->address() == (*plast
)->address()
4678 && (*p
)->data_size() > (*plast
)->data_size()))
4682 this->vaddr_
= first
->address();
4683 this->paddr_
= (first
->has_load_address()
4684 ? first
->load_address()
4686 this->are_addresses_set_
= true;
4687 this->offset_
= first
->offset();
4689 if (last_data
== NULL
)
4692 this->filesz_
= (last_data
->address()
4693 + last_data
->data_size()
4696 const Output_data
* last
= last_bss
!= NULL
? last_bss
: last_data
;
4697 this->memsz_
= (last
->address()
4701 this->filesz_
+= increase
;
4702 this->memsz_
+= increase
;
4704 // If this is a RELRO segment, verify that the segment ends at a
4706 if (this->type_
== elfcpp::PT_GNU_RELRO
)
4708 uint64_t page_align
= parameters
->target().abi_pagesize();
4709 uint64_t segment_end
= this->vaddr_
+ this->memsz_
;
4710 if (parameters
->incremental_update())
4712 // The INCREASE_RELRO calculation is bypassed for an incremental
4713 // update, so we need to adjust the segment size manually here.
4714 segment_end
= align_address(segment_end
, page_align
);
4715 this->memsz_
= segment_end
- this->vaddr_
;
4718 gold_assert(segment_end
== align_address(segment_end
, page_align
));
4721 // If this is a TLS segment, align the memory size. The code in
4722 // set_section_list ensures that the section after the TLS segment
4723 // is aligned to give us room.
4724 if (this->type_
== elfcpp::PT_TLS
)
4726 uint64_t segment_align
= this->maximum_alignment();
4727 gold_assert(this->vaddr_
== align_address(this->vaddr_
, segment_align
));
4728 this->memsz_
= align_address(this->memsz_
, segment_align
);
4732 // Set the TLS offsets of the sections in the PT_TLS segment.
4735 Output_segment::set_tls_offsets()
4737 gold_assert(this->type_
== elfcpp::PT_TLS
);
4739 for (Output_data_list::iterator p
= this->output_lists_
[0].begin();
4740 p
!= this->output_lists_
[0].end();
4742 (*p
)->set_tls_offset(this->vaddr_
);
4745 // Return the first section.
4748 Output_segment::first_section() const
4750 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4752 const Output_data_list
* pdl
= &this->output_lists_
[i
];
4753 for (Output_data_list::const_iterator p
= pdl
->begin();
4757 if ((*p
)->is_section())
4758 return (*p
)->output_section();
4764 // Return the number of Output_sections in an Output_segment.
4767 Output_segment::output_section_count() const
4769 unsigned int ret
= 0;
4770 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4771 ret
+= this->output_section_count_list(&this->output_lists_
[i
]);
4775 // Return the number of Output_sections in an Output_data_list.
4778 Output_segment::output_section_count_list(const Output_data_list
* pdl
) const
4780 unsigned int count
= 0;
4781 for (Output_data_list::const_iterator p
= pdl
->begin();
4785 if ((*p
)->is_section())
4791 // Return the section attached to the list segment with the lowest
4792 // load address. This is used when handling a PHDRS clause in a
4796 Output_segment::section_with_lowest_load_address() const
4798 Output_section
* found
= NULL
;
4799 uint64_t found_lma
= 0;
4800 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4801 this->lowest_load_address_in_list(&this->output_lists_
[i
], &found
,
4806 // Look through a list for a section with a lower load address.
4809 Output_segment::lowest_load_address_in_list(const Output_data_list
* pdl
,
4810 Output_section
** found
,
4811 uint64_t* found_lma
) const
4813 for (Output_data_list::const_iterator p
= pdl
->begin();
4817 if (!(*p
)->is_section())
4819 Output_section
* os
= static_cast<Output_section
*>(*p
);
4820 uint64_t lma
= (os
->has_load_address()
4821 ? os
->load_address()
4823 if (*found
== NULL
|| lma
< *found_lma
)
4831 // Write the segment data into *OPHDR.
4833 template<int size
, bool big_endian
>
4835 Output_segment::write_header(elfcpp::Phdr_write
<size
, big_endian
>* ophdr
)
4837 ophdr
->put_p_type(this->type_
);
4838 ophdr
->put_p_offset(this->offset_
);
4839 ophdr
->put_p_vaddr(this->vaddr_
);
4840 ophdr
->put_p_paddr(this->paddr_
);
4841 ophdr
->put_p_filesz(this->filesz_
);
4842 ophdr
->put_p_memsz(this->memsz_
);
4843 ophdr
->put_p_flags(this->flags_
);
4844 ophdr
->put_p_align(std::max(this->min_p_align_
, this->maximum_alignment()));
4847 // Write the section headers into V.
4849 template<int size
, bool big_endian
>
4851 Output_segment::write_section_headers(const Layout
* layout
,
4852 const Stringpool
* secnamepool
,
4854 unsigned int* pshndx
) const
4856 // Every section that is attached to a segment must be attached to a
4857 // PT_LOAD segment, so we only write out section headers for PT_LOAD
4859 if (this->type_
!= elfcpp::PT_LOAD
)
4862 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4864 const Output_data_list
* pdl
= &this->output_lists_
[i
];
4865 v
= this->write_section_headers_list
<size
, big_endian
>(layout
,
4874 template<int size
, bool big_endian
>
4876 Output_segment::write_section_headers_list(const Layout
* layout
,
4877 const Stringpool
* secnamepool
,
4878 const Output_data_list
* pdl
,
4880 unsigned int* pshndx
) const
4882 const int shdr_size
= elfcpp::Elf_sizes
<size
>::shdr_size
;
4883 for (Output_data_list::const_iterator p
= pdl
->begin();
4887 if ((*p
)->is_section())
4889 const Output_section
* ps
= static_cast<const Output_section
*>(*p
);
4890 gold_assert(*pshndx
== ps
->out_shndx());
4891 elfcpp::Shdr_write
<size
, big_endian
> oshdr(v
);
4892 ps
->write_header(layout
, secnamepool
, &oshdr
);
4900 // Print the output sections to the map file.
4903 Output_segment::print_sections_to_mapfile(Mapfile
* mapfile
) const
4905 if (this->type() != elfcpp::PT_LOAD
)
4907 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4908 this->print_section_list_to_mapfile(mapfile
, &this->output_lists_
[i
]);
4911 // Print an output section list to the map file.
4914 Output_segment::print_section_list_to_mapfile(Mapfile
* mapfile
,
4915 const Output_data_list
* pdl
) const
4917 for (Output_data_list::const_iterator p
= pdl
->begin();
4920 (*p
)->print_to_mapfile(mapfile
);
4923 // Output_file methods.
4925 Output_file::Output_file(const char* name
)
4930 map_is_anonymous_(false),
4931 map_is_allocated_(false),
4932 is_temporary_(false)
4936 // Try to open an existing file. Returns false if the file doesn't
4937 // exist, has a size of 0 or can't be mmapped. If BASE_NAME is not
4938 // NULL, open that file as the base for incremental linking, and
4939 // copy its contents to the new output file. This routine can
4940 // be called for incremental updates, in which case WRITABLE should
4941 // be true, or by the incremental-dump utility, in which case
4942 // WRITABLE should be false.
4945 Output_file::open_base_file(const char* base_name
, bool writable
)
4947 // The name "-" means "stdout".
4948 if (strcmp(this->name_
, "-") == 0)
4951 bool use_base_file
= base_name
!= NULL
;
4953 base_name
= this->name_
;
4954 else if (strcmp(base_name
, this->name_
) == 0)
4955 gold_fatal(_("%s: incremental base and output file name are the same"),
4958 // Don't bother opening files with a size of zero.
4960 if (::stat(base_name
, &s
) != 0)
4962 gold_info(_("%s: stat: %s"), base_name
, strerror(errno
));
4967 gold_info(_("%s: incremental base file is empty"), base_name
);
4971 // If we're using a base file, we want to open it read-only.
4975 int oflags
= writable
? O_RDWR
: O_RDONLY
;
4976 int o
= open_descriptor(-1, base_name
, oflags
, 0);
4979 gold_info(_("%s: open: %s"), base_name
, strerror(errno
));
4983 // If the base file and the output file are different, open a
4984 // new output file and read the contents from the base file into
4985 // the newly-mapped region.
4988 this->open(s
.st_size
);
4989 ssize_t bytes_to_read
= s
.st_size
;
4990 unsigned char* p
= this->base_
;
4991 while (bytes_to_read
> 0)
4993 ssize_t len
= ::read(o
, p
, bytes_to_read
);
4996 gold_info(_("%s: read failed: %s"), base_name
, strerror(errno
));
5001 gold_info(_("%s: file too short: read only %lld of %lld bytes"),
5003 static_cast<long long>(s
.st_size
- bytes_to_read
),
5004 static_cast<long long>(s
.st_size
));
5008 bytes_to_read
-= len
;
5015 this->file_size_
= s
.st_size
;
5017 if (!this->map_no_anonymous(writable
))
5019 release_descriptor(o
, true);
5021 this->file_size_
= 0;
5028 // Open the output file.
5031 Output_file::open(off_t file_size
)
5033 this->file_size_
= file_size
;
5035 // Unlink the file first; otherwise the open() may fail if the file
5036 // is busy (e.g. it's an executable that's currently being executed).
5038 // However, the linker may be part of a system where a zero-length
5039 // file is created for it to write to, with tight permissions (gcc
5040 // 2.95 did something like this). Unlinking the file would work
5041 // around those permission controls, so we only unlink if the file
5042 // has a non-zero size. We also unlink only regular files to avoid
5043 // trouble with directories/etc.
5045 // If we fail, continue; this command is merely a best-effort attempt
5046 // to improve the odds for open().
5048 // We let the name "-" mean "stdout"
5049 if (!this->is_temporary_
)
5051 if (strcmp(this->name_
, "-") == 0)
5052 this->o_
= STDOUT_FILENO
;
5056 if (::stat(this->name_
, &s
) == 0
5057 && (S_ISREG (s
.st_mode
) || S_ISLNK (s
.st_mode
)))
5060 ::unlink(this->name_
);
5061 else if (!parameters
->options().relocatable())
5063 // If we don't unlink the existing file, add execute
5064 // permission where read permissions already exist
5065 // and where the umask permits.
5066 int mask
= ::umask(0);
5068 s
.st_mode
|= (s
.st_mode
& 0444) >> 2;
5069 ::chmod(this->name_
, s
.st_mode
& ~mask
);
5073 int mode
= parameters
->options().relocatable() ? 0666 : 0777;
5074 int o
= open_descriptor(-1, this->name_
, O_RDWR
| O_CREAT
| O_TRUNC
,
5077 gold_fatal(_("%s: open: %s"), this->name_
, strerror(errno
));
5085 // Resize the output file.
5088 Output_file::resize(off_t file_size
)
5090 // If the mmap is mapping an anonymous memory buffer, this is easy:
5091 // just mremap to the new size. If it's mapping to a file, we want
5092 // to unmap to flush to the file, then remap after growing the file.
5093 if (this->map_is_anonymous_
)
5096 if (!this->map_is_allocated_
)
5098 base
= ::mremap(this->base_
, this->file_size_
, file_size
,
5100 if (base
== MAP_FAILED
)
5101 gold_fatal(_("%s: mremap: %s"), this->name_
, strerror(errno
));
5105 base
= realloc(this->base_
, file_size
);
5108 if (file_size
> this->file_size_
)
5109 memset(static_cast<char*>(base
) + this->file_size_
, 0,
5110 file_size
- this->file_size_
);
5112 this->base_
= static_cast<unsigned char*>(base
);
5113 this->file_size_
= file_size
;
5118 this->file_size_
= file_size
;
5119 if (!this->map_no_anonymous(true))
5120 gold_fatal(_("%s: mmap: %s"), this->name_
, strerror(errno
));
5124 // Map an anonymous block of memory which will later be written to the
5125 // file. Return whether the map succeeded.
5128 Output_file::map_anonymous()
5130 void* base
= ::mmap(NULL
, this->file_size_
, PROT_READ
| PROT_WRITE
,
5131 MAP_PRIVATE
| MAP_ANONYMOUS
, -1, 0);
5132 if (base
== MAP_FAILED
)
5134 base
= malloc(this->file_size_
);
5137 memset(base
, 0, this->file_size_
);
5138 this->map_is_allocated_
= true;
5140 this->base_
= static_cast<unsigned char*>(base
);
5141 this->map_is_anonymous_
= true;
5145 // Map the file into memory. Return whether the mapping succeeded.
5146 // If WRITABLE is true, map with write access.
5149 Output_file::map_no_anonymous(bool writable
)
5151 const int o
= this->o_
;
5153 // If the output file is not a regular file, don't try to mmap it;
5154 // instead, we'll mmap a block of memory (an anonymous buffer), and
5155 // then later write the buffer to the file.
5157 struct stat statbuf
;
5158 if (o
== STDOUT_FILENO
|| o
== STDERR_FILENO
5159 || ::fstat(o
, &statbuf
) != 0
5160 || !S_ISREG(statbuf
.st_mode
)
5161 || this->is_temporary_
)
5164 // Ensure that we have disk space available for the file. If we
5165 // don't do this, it is possible that we will call munmap, close,
5166 // and exit with dirty buffers still in the cache with no assigned
5167 // disk blocks. If the disk is out of space at that point, the
5168 // output file will wind up incomplete, but we will have already
5169 // exited. The alternative to fallocate would be to use fdatasync,
5170 // but that would be a more significant performance hit.
5173 int err
= gold_fallocate(o
, 0, this->file_size_
);
5175 gold_fatal(_("%s: %s"), this->name_
, strerror(err
));
5178 // Map the file into memory.
5179 int prot
= PROT_READ
;
5182 base
= ::mmap(NULL
, this->file_size_
, prot
, MAP_SHARED
, o
, 0);
5184 // The mmap call might fail because of file system issues: the file
5185 // system might not support mmap at all, or it might not support
5186 // mmap with PROT_WRITE.
5187 if (base
== MAP_FAILED
)
5190 this->map_is_anonymous_
= false;
5191 this->base_
= static_cast<unsigned char*>(base
);
5195 // Map the file into memory.
5200 if (parameters
->options().mmap_output_file()
5201 && this->map_no_anonymous(true))
5204 // The mmap call might fail because of file system issues: the file
5205 // system might not support mmap at all, or it might not support
5206 // mmap with PROT_WRITE. I'm not sure which errno values we will
5207 // see in all cases, so if the mmap fails for any reason and we
5208 // don't care about file contents, try for an anonymous map.
5209 if (this->map_anonymous())
5212 gold_fatal(_("%s: mmap: failed to allocate %lu bytes for output file: %s"),
5213 this->name_
, static_cast<unsigned long>(this->file_size_
),
5217 // Unmap the file from memory.
5220 Output_file::unmap()
5222 if (this->map_is_anonymous_
)
5224 // We've already written out the data, so there is no reason to
5225 // waste time unmapping or freeing the memory.
5229 if (::munmap(this->base_
, this->file_size_
) < 0)
5230 gold_error(_("%s: munmap: %s"), this->name_
, strerror(errno
));
5235 // Close the output file.
5238 Output_file::close()
5240 // If the map isn't file-backed, we need to write it now.
5241 if (this->map_is_anonymous_
&& !this->is_temporary_
)
5243 size_t bytes_to_write
= this->file_size_
;
5245 while (bytes_to_write
> 0)
5247 ssize_t bytes_written
= ::write(this->o_
, this->base_
+ offset
,
5249 if (bytes_written
== 0)
5250 gold_error(_("%s: write: unexpected 0 return-value"), this->name_
);
5251 else if (bytes_written
< 0)
5252 gold_error(_("%s: write: %s"), this->name_
, strerror(errno
));
5255 bytes_to_write
-= bytes_written
;
5256 offset
+= bytes_written
;
5262 // We don't close stdout or stderr
5263 if (this->o_
!= STDOUT_FILENO
5264 && this->o_
!= STDERR_FILENO
5265 && !this->is_temporary_
)
5266 if (::close(this->o_
) < 0)
5267 gold_error(_("%s: close: %s"), this->name_
, strerror(errno
));
5271 // Instantiate the templates we need. We could use the configure
5272 // script to restrict this to only the ones for implemented targets.
5274 #ifdef HAVE_TARGET_32_LITTLE
5277 Output_section::add_input_section
<32, false>(
5279 Sized_relobj_file
<32, false>* object
,
5281 const char* secname
,
5282 const elfcpp::Shdr
<32, false>& shdr
,
5283 unsigned int reloc_shndx
,
5284 bool have_sections_script
);
5287 #ifdef HAVE_TARGET_32_BIG
5290 Output_section::add_input_section
<32, true>(
5292 Sized_relobj_file
<32, true>* object
,
5294 const char* secname
,
5295 const elfcpp::Shdr
<32, true>& shdr
,
5296 unsigned int reloc_shndx
,
5297 bool have_sections_script
);
5300 #ifdef HAVE_TARGET_64_LITTLE
5303 Output_section::add_input_section
<64, false>(
5305 Sized_relobj_file
<64, false>* object
,
5307 const char* secname
,
5308 const elfcpp::Shdr
<64, false>& shdr
,
5309 unsigned int reloc_shndx
,
5310 bool have_sections_script
);
5313 #ifdef HAVE_TARGET_64_BIG
5316 Output_section::add_input_section
<64, true>(
5318 Sized_relobj_file
<64, true>* object
,
5320 const char* secname
,
5321 const elfcpp::Shdr
<64, true>& shdr
,
5322 unsigned int reloc_shndx
,
5323 bool have_sections_script
);
5326 #ifdef HAVE_TARGET_32_LITTLE
5328 class Output_reloc
<elfcpp::SHT_REL
, false, 32, false>;
5331 #ifdef HAVE_TARGET_32_BIG
5333 class Output_reloc
<elfcpp::SHT_REL
, false, 32, true>;
5336 #ifdef HAVE_TARGET_64_LITTLE
5338 class Output_reloc
<elfcpp::SHT_REL
, false, 64, false>;
5341 #ifdef HAVE_TARGET_64_BIG
5343 class Output_reloc
<elfcpp::SHT_REL
, false, 64, true>;
5346 #ifdef HAVE_TARGET_32_LITTLE
5348 class Output_reloc
<elfcpp::SHT_REL
, true, 32, false>;
5351 #ifdef HAVE_TARGET_32_BIG
5353 class Output_reloc
<elfcpp::SHT_REL
, true, 32, true>;
5356 #ifdef HAVE_TARGET_64_LITTLE
5358 class Output_reloc
<elfcpp::SHT_REL
, true, 64, false>;
5361 #ifdef HAVE_TARGET_64_BIG
5363 class Output_reloc
<elfcpp::SHT_REL
, true, 64, true>;
5366 #ifdef HAVE_TARGET_32_LITTLE
5368 class Output_reloc
<elfcpp::SHT_RELA
, false, 32, false>;
5371 #ifdef HAVE_TARGET_32_BIG
5373 class Output_reloc
<elfcpp::SHT_RELA
, false, 32, true>;
5376 #ifdef HAVE_TARGET_64_LITTLE
5378 class Output_reloc
<elfcpp::SHT_RELA
, false, 64, false>;
5381 #ifdef HAVE_TARGET_64_BIG
5383 class Output_reloc
<elfcpp::SHT_RELA
, false, 64, true>;
5386 #ifdef HAVE_TARGET_32_LITTLE
5388 class Output_reloc
<elfcpp::SHT_RELA
, true, 32, false>;
5391 #ifdef HAVE_TARGET_32_BIG
5393 class Output_reloc
<elfcpp::SHT_RELA
, true, 32, true>;
5396 #ifdef HAVE_TARGET_64_LITTLE
5398 class Output_reloc
<elfcpp::SHT_RELA
, true, 64, false>;
5401 #ifdef HAVE_TARGET_64_BIG
5403 class Output_reloc
<elfcpp::SHT_RELA
, true, 64, true>;
5406 #ifdef HAVE_TARGET_32_LITTLE
5408 class Output_data_reloc
<elfcpp::SHT_REL
, false, 32, false>;
5411 #ifdef HAVE_TARGET_32_BIG
5413 class Output_data_reloc
<elfcpp::SHT_REL
, false, 32, true>;
5416 #ifdef HAVE_TARGET_64_LITTLE
5418 class Output_data_reloc
<elfcpp::SHT_REL
, false, 64, false>;
5421 #ifdef HAVE_TARGET_64_BIG
5423 class Output_data_reloc
<elfcpp::SHT_REL
, false, 64, true>;
5426 #ifdef HAVE_TARGET_32_LITTLE
5428 class Output_data_reloc
<elfcpp::SHT_REL
, true, 32, false>;
5431 #ifdef HAVE_TARGET_32_BIG
5433 class Output_data_reloc
<elfcpp::SHT_REL
, true, 32, true>;
5436 #ifdef HAVE_TARGET_64_LITTLE
5438 class Output_data_reloc
<elfcpp::SHT_REL
, true, 64, false>;
5441 #ifdef HAVE_TARGET_64_BIG
5443 class Output_data_reloc
<elfcpp::SHT_REL
, true, 64, true>;
5446 #ifdef HAVE_TARGET_32_LITTLE
5448 class Output_data_reloc
<elfcpp::SHT_RELA
, false, 32, false>;
5451 #ifdef HAVE_TARGET_32_BIG
5453 class Output_data_reloc
<elfcpp::SHT_RELA
, false, 32, true>;
5456 #ifdef HAVE_TARGET_64_LITTLE
5458 class Output_data_reloc
<elfcpp::SHT_RELA
, false, 64, false>;
5461 #ifdef HAVE_TARGET_64_BIG
5463 class Output_data_reloc
<elfcpp::SHT_RELA
, false, 64, true>;
5466 #ifdef HAVE_TARGET_32_LITTLE
5468 class Output_data_reloc
<elfcpp::SHT_RELA
, true, 32, false>;
5471 #ifdef HAVE_TARGET_32_BIG
5473 class Output_data_reloc
<elfcpp::SHT_RELA
, true, 32, true>;
5476 #ifdef HAVE_TARGET_64_LITTLE
5478 class Output_data_reloc
<elfcpp::SHT_RELA
, true, 64, false>;
5481 #ifdef HAVE_TARGET_64_BIG
5483 class Output_data_reloc
<elfcpp::SHT_RELA
, true, 64, true>;
5486 #ifdef HAVE_TARGET_32_LITTLE
5488 class Output_relocatable_relocs
<elfcpp::SHT_REL
, 32, false>;
5491 #ifdef HAVE_TARGET_32_BIG
5493 class Output_relocatable_relocs
<elfcpp::SHT_REL
, 32, true>;
5496 #ifdef HAVE_TARGET_64_LITTLE
5498 class Output_relocatable_relocs
<elfcpp::SHT_REL
, 64, false>;
5501 #ifdef HAVE_TARGET_64_BIG
5503 class Output_relocatable_relocs
<elfcpp::SHT_REL
, 64, true>;
5506 #ifdef HAVE_TARGET_32_LITTLE
5508 class Output_relocatable_relocs
<elfcpp::SHT_RELA
, 32, false>;
5511 #ifdef HAVE_TARGET_32_BIG
5513 class Output_relocatable_relocs
<elfcpp::SHT_RELA
, 32, true>;
5516 #ifdef HAVE_TARGET_64_LITTLE
5518 class Output_relocatable_relocs
<elfcpp::SHT_RELA
, 64, false>;
5521 #ifdef HAVE_TARGET_64_BIG
5523 class Output_relocatable_relocs
<elfcpp::SHT_RELA
, 64, true>;
5526 #ifdef HAVE_TARGET_32_LITTLE
5528 class Output_data_group
<32, false>;
5531 #ifdef HAVE_TARGET_32_BIG
5533 class Output_data_group
<32, true>;
5536 #ifdef HAVE_TARGET_64_LITTLE
5538 class Output_data_group
<64, false>;
5541 #ifdef HAVE_TARGET_64_BIG
5543 class Output_data_group
<64, true>;
5547 class Output_data_got
<32, false>;
5550 class Output_data_got
<32, true>;
5553 class Output_data_got
<64, false>;
5556 class Output_data_got
<64, true>;
5558 } // End namespace gold.