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
, 0);
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 // Like add_local, but use the PLT offset.
1553 template<int got_size
, bool big_endian
>
1555 Output_data_got
<got_size
, big_endian
>::add_local_plt(
1557 unsigned int symndx
,
1558 unsigned int got_type
)
1560 if (object
->local_has_got_offset(symndx
, got_type
))
1563 unsigned int got_offset
= this->add_got_entry(Got_entry(object
, symndx
,
1565 object
->set_local_got_offset(symndx
, got_type
, got_offset
);
1569 // Add an entry for a local symbol to the GOT, and add a dynamic
1570 // relocation of type R_TYPE for the GOT entry.
1572 template<int got_size
, bool big_endian
>
1574 Output_data_got
<got_size
, big_endian
>::add_local_with_rel(
1576 unsigned int symndx
,
1577 unsigned int got_type
,
1578 Output_data_reloc_generic
* rel_dyn
,
1579 unsigned int r_type
)
1581 if (object
->local_has_got_offset(symndx
, got_type
))
1584 unsigned int got_offset
= this->add_got_entry(Got_entry());
1585 object
->set_local_got_offset(symndx
, got_type
, got_offset
);
1586 rel_dyn
->add_local_generic(object
, symndx
, r_type
, this, got_offset
, 0);
1589 // Add a pair of entries for a local symbol to the GOT, and add
1590 // a dynamic relocation of type R_TYPE using the section symbol of
1591 // the output section to which input section SHNDX maps, on the first.
1592 // The first got entry will have a value of zero, the second the
1593 // value of the local symbol.
1594 template<int got_size
, bool big_endian
>
1596 Output_data_got
<got_size
, big_endian
>::add_local_pair_with_rel(
1598 unsigned int symndx
,
1600 unsigned int got_type
,
1601 Output_data_reloc_generic
* rel_dyn
,
1602 unsigned int r_type
)
1604 if (object
->local_has_got_offset(symndx
, got_type
))
1607 unsigned int got_offset
=
1608 this->add_got_entry_pair(Got_entry(),
1609 Got_entry(object
, symndx
, false));
1610 object
->set_local_got_offset(symndx
, got_type
, got_offset
);
1611 Output_section
* os
= object
->output_section(shndx
);
1612 rel_dyn
->add_output_section_generic(os
, r_type
, this, got_offset
, 0);
1615 // Add a pair of entries for a local symbol to the GOT, and add
1616 // a dynamic relocation of type R_TYPE using STN_UNDEF on the first.
1617 // The first got entry will have a value of zero, the second the
1618 // value of the local symbol offset by Target::tls_offset_for_local.
1619 template<int got_size
, bool big_endian
>
1621 Output_data_got
<got_size
, big_endian
>::add_local_tls_pair(
1623 unsigned int symndx
,
1624 unsigned int got_type
,
1625 Output_data_reloc_generic
* rel_dyn
,
1626 unsigned int r_type
)
1628 if (object
->local_has_got_offset(symndx
, got_type
))
1631 unsigned int got_offset
1632 = this->add_got_entry_pair(Got_entry(),
1633 Got_entry(object
, symndx
, true));
1634 object
->set_local_got_offset(symndx
, got_type
, got_offset
);
1635 rel_dyn
->add_local_generic(object
, 0, r_type
, this, got_offset
, 0);
1638 // Reserve a slot in the GOT for a local symbol or the second slot of a pair.
1640 template<int got_size
, bool big_endian
>
1642 Output_data_got
<got_size
, big_endian
>::reserve_local(
1645 unsigned int sym_index
,
1646 unsigned int got_type
)
1648 this->do_reserve_slot(i
);
1649 object
->set_local_got_offset(sym_index
, got_type
, this->got_offset(i
));
1652 // Reserve a slot in the GOT for a global symbol.
1654 template<int got_size
, bool big_endian
>
1656 Output_data_got
<got_size
, big_endian
>::reserve_global(
1659 unsigned int got_type
)
1661 this->do_reserve_slot(i
);
1662 gsym
->set_got_offset(got_type
, this->got_offset(i
));
1665 // Write out the GOT.
1667 template<int got_size
, bool big_endian
>
1669 Output_data_got
<got_size
, big_endian
>::do_write(Output_file
* of
)
1671 const int add
= got_size
/ 8;
1673 const off_t off
= this->offset();
1674 const off_t oview_size
= this->data_size();
1675 unsigned char* const oview
= of
->get_output_view(off
, oview_size
);
1677 unsigned char* pov
= oview
;
1678 for (unsigned int i
= 0; i
< this->entries_
.size(); ++i
)
1680 this->entries_
[i
].write(i
, pov
);
1684 gold_assert(pov
- oview
== oview_size
);
1686 of
->write_output_view(off
, oview_size
, oview
);
1688 // We no longer need the GOT entries.
1689 this->entries_
.clear();
1692 // Create a new GOT entry and return its offset.
1694 template<int got_size
, bool big_endian
>
1696 Output_data_got
<got_size
, big_endian
>::add_got_entry(Got_entry got_entry
)
1698 if (!this->is_data_size_valid())
1700 this->entries_
.push_back(got_entry
);
1701 this->set_got_size();
1702 return this->last_got_offset();
1706 // For an incremental update, find an available slot.
1707 off_t got_offset
= this->free_list_
.allocate(got_size
/ 8,
1709 if (got_offset
== -1)
1710 gold_fallback(_("out of patch space (GOT);"
1711 " relink with --incremental-full"));
1712 unsigned int got_index
= got_offset
/ (got_size
/ 8);
1713 gold_assert(got_index
< this->entries_
.size());
1714 this->entries_
[got_index
] = got_entry
;
1715 return static_cast<unsigned int>(got_offset
);
1719 // Create a pair of new GOT entries and return the offset of the first.
1721 template<int got_size
, bool big_endian
>
1723 Output_data_got
<got_size
, big_endian
>::add_got_entry_pair(
1724 Got_entry got_entry_1
,
1725 Got_entry got_entry_2
)
1727 if (!this->is_data_size_valid())
1729 unsigned int got_offset
;
1730 this->entries_
.push_back(got_entry_1
);
1731 got_offset
= this->last_got_offset();
1732 this->entries_
.push_back(got_entry_2
);
1733 this->set_got_size();
1738 // For an incremental update, find an available pair of slots.
1739 off_t got_offset
= this->free_list_
.allocate(2 * got_size
/ 8,
1741 if (got_offset
== -1)
1742 gold_fallback(_("out of patch space (GOT);"
1743 " relink with --incremental-full"));
1744 unsigned int got_index
= got_offset
/ (got_size
/ 8);
1745 gold_assert(got_index
< this->entries_
.size());
1746 this->entries_
[got_index
] = got_entry_1
;
1747 this->entries_
[got_index
+ 1] = got_entry_2
;
1748 return static_cast<unsigned int>(got_offset
);
1752 // Replace GOT entry I with a new value.
1754 template<int got_size
, bool big_endian
>
1756 Output_data_got
<got_size
, big_endian
>::replace_got_entry(
1758 Got_entry got_entry
)
1760 gold_assert(i
< this->entries_
.size());
1761 this->entries_
[i
] = got_entry
;
1764 // Output_data_dynamic::Dynamic_entry methods.
1766 // Write out the entry.
1768 template<int size
, bool big_endian
>
1770 Output_data_dynamic::Dynamic_entry::write(
1772 const Stringpool
* pool
) const
1774 typename
elfcpp::Elf_types
<size
>::Elf_WXword val
;
1775 switch (this->offset_
)
1777 case DYNAMIC_NUMBER
:
1781 case DYNAMIC_SECTION_SIZE
:
1782 val
= this->u_
.od
->data_size();
1783 if (this->od2
!= NULL
)
1784 val
+= this->od2
->data_size();
1787 case DYNAMIC_SYMBOL
:
1789 const Sized_symbol
<size
>* s
=
1790 static_cast<const Sized_symbol
<size
>*>(this->u_
.sym
);
1795 case DYNAMIC_STRING
:
1796 val
= pool
->get_offset(this->u_
.str
);
1799 case DYNAMIC_CUSTOM
:
1800 val
= parameters
->target().dynamic_tag_custom_value(this->tag_
);
1804 val
= this->u_
.od
->address() + this->offset_
;
1808 elfcpp::Dyn_write
<size
, big_endian
> dw(pov
);
1809 dw
.put_d_tag(this->tag_
);
1813 // Output_data_dynamic methods.
1815 // Adjust the output section to set the entry size.
1818 Output_data_dynamic::do_adjust_output_section(Output_section
* os
)
1820 if (parameters
->target().get_size() == 32)
1821 os
->set_entsize(elfcpp::Elf_sizes
<32>::dyn_size
);
1822 else if (parameters
->target().get_size() == 64)
1823 os
->set_entsize(elfcpp::Elf_sizes
<64>::dyn_size
);
1828 // Set the final data size.
1831 Output_data_dynamic::set_final_data_size()
1833 // Add the terminating entry if it hasn't been added.
1834 // Because of relaxation, we can run this multiple times.
1835 if (this->entries_
.empty() || this->entries_
.back().tag() != elfcpp::DT_NULL
)
1837 int extra
= parameters
->options().spare_dynamic_tags();
1838 for (int i
= 0; i
< extra
; ++i
)
1839 this->add_constant(elfcpp::DT_NULL
, 0);
1840 this->add_constant(elfcpp::DT_NULL
, 0);
1844 if (parameters
->target().get_size() == 32)
1845 dyn_size
= elfcpp::Elf_sizes
<32>::dyn_size
;
1846 else if (parameters
->target().get_size() == 64)
1847 dyn_size
= elfcpp::Elf_sizes
<64>::dyn_size
;
1850 this->set_data_size(this->entries_
.size() * dyn_size
);
1853 // Write out the dynamic entries.
1856 Output_data_dynamic::do_write(Output_file
* of
)
1858 switch (parameters
->size_and_endianness())
1860 #ifdef HAVE_TARGET_32_LITTLE
1861 case Parameters::TARGET_32_LITTLE
:
1862 this->sized_write
<32, false>(of
);
1865 #ifdef HAVE_TARGET_32_BIG
1866 case Parameters::TARGET_32_BIG
:
1867 this->sized_write
<32, true>(of
);
1870 #ifdef HAVE_TARGET_64_LITTLE
1871 case Parameters::TARGET_64_LITTLE
:
1872 this->sized_write
<64, false>(of
);
1875 #ifdef HAVE_TARGET_64_BIG
1876 case Parameters::TARGET_64_BIG
:
1877 this->sized_write
<64, true>(of
);
1885 template<int size
, bool big_endian
>
1887 Output_data_dynamic::sized_write(Output_file
* of
)
1889 const int dyn_size
= elfcpp::Elf_sizes
<size
>::dyn_size
;
1891 const off_t offset
= this->offset();
1892 const off_t oview_size
= this->data_size();
1893 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
1895 unsigned char* pov
= oview
;
1896 for (typename
Dynamic_entries::const_iterator p
= this->entries_
.begin();
1897 p
!= this->entries_
.end();
1900 p
->write
<size
, big_endian
>(pov
, this->pool_
);
1904 gold_assert(pov
- oview
== oview_size
);
1906 of
->write_output_view(offset
, oview_size
, oview
);
1908 // We no longer need the dynamic entries.
1909 this->entries_
.clear();
1912 // Class Output_symtab_xindex.
1915 Output_symtab_xindex::do_write(Output_file
* of
)
1917 const off_t offset
= this->offset();
1918 const off_t oview_size
= this->data_size();
1919 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
1921 memset(oview
, 0, oview_size
);
1923 if (parameters
->target().is_big_endian())
1924 this->endian_do_write
<true>(oview
);
1926 this->endian_do_write
<false>(oview
);
1928 of
->write_output_view(offset
, oview_size
, oview
);
1930 // We no longer need the data.
1931 this->entries_
.clear();
1934 template<bool big_endian
>
1936 Output_symtab_xindex::endian_do_write(unsigned char* const oview
)
1938 for (Xindex_entries::const_iterator p
= this->entries_
.begin();
1939 p
!= this->entries_
.end();
1942 unsigned int symndx
= p
->first
;
1943 gold_assert(static_cast<off_t
>(symndx
) * 4 < this->data_size());
1944 elfcpp::Swap
<32, big_endian
>::writeval(oview
+ symndx
* 4, p
->second
);
1948 // Output_fill_debug_info methods.
1950 // Return the minimum size needed for a dummy compilation unit header.
1953 Output_fill_debug_info::do_minimum_hole_size() const
1955 // Compile unit header fields: unit_length, version, debug_abbrev_offset,
1957 const size_t len
= 4 + 2 + 4 + 1;
1958 // For type units, add type_signature, type_offset.
1959 if (this->is_debug_types_
)
1964 // Write a dummy compilation unit header to fill a hole in the
1965 // .debug_info or .debug_types section.
1968 Output_fill_debug_info::do_write(Output_file
* of
, off_t off
, size_t len
) const
1970 gold_debug(DEBUG_INCREMENTAL
, "fill_debug_info(%08lx, %08lx)",
1971 static_cast<long>(off
), static_cast<long>(len
));
1973 gold_assert(len
>= this->do_minimum_hole_size());
1975 unsigned char* const oview
= of
->get_output_view(off
, len
);
1976 unsigned char* pov
= oview
;
1978 // Write header fields: unit_length, version, debug_abbrev_offset,
1980 if (this->is_big_endian())
1982 elfcpp::Swap_unaligned
<32, true>::writeval(pov
, len
- 4);
1983 elfcpp::Swap_unaligned
<16, true>::writeval(pov
+ 4, this->version
);
1984 elfcpp::Swap_unaligned
<32, true>::writeval(pov
+ 6, 0);
1988 elfcpp::Swap_unaligned
<32, false>::writeval(pov
, len
- 4);
1989 elfcpp::Swap_unaligned
<16, false>::writeval(pov
+ 4, this->version
);
1990 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 6, 0);
1995 // For type units, the additional header fields -- type_signature,
1996 // type_offset -- can be filled with zeroes.
1998 // Fill the remainder of the free space with zeroes. The first
1999 // zero should tell the consumer there are no DIEs to read in this
2000 // compilation unit.
2001 if (pov
< oview
+ len
)
2002 memset(pov
, 0, oview
+ len
- pov
);
2004 of
->write_output_view(off
, len
, oview
);
2007 // Output_fill_debug_line methods.
2009 // Return the minimum size needed for a dummy line number program header.
2012 Output_fill_debug_line::do_minimum_hole_size() const
2014 // Line number program header fields: unit_length, version, header_length,
2015 // minimum_instruction_length, default_is_stmt, line_base, line_range,
2016 // opcode_base, standard_opcode_lengths[], include_directories, filenames.
2017 const size_t len
= 4 + 2 + 4 + this->header_length
;
2021 // Write a dummy line number program header to fill a hole in the
2022 // .debug_line section.
2025 Output_fill_debug_line::do_write(Output_file
* of
, off_t off
, size_t len
) const
2027 gold_debug(DEBUG_INCREMENTAL
, "fill_debug_line(%08lx, %08lx)",
2028 static_cast<long>(off
), static_cast<long>(len
));
2030 gold_assert(len
>= this->do_minimum_hole_size());
2032 unsigned char* const oview
= of
->get_output_view(off
, len
);
2033 unsigned char* pov
= oview
;
2035 // Write header fields: unit_length, version, header_length,
2036 // minimum_instruction_length, default_is_stmt, line_base, line_range,
2037 // opcode_base, standard_opcode_lengths[], include_directories, filenames.
2038 // We set the header_length field to cover the entire hole, so the
2039 // line number program is empty.
2040 if (this->is_big_endian())
2042 elfcpp::Swap_unaligned
<32, true>::writeval(pov
, len
- 4);
2043 elfcpp::Swap_unaligned
<16, true>::writeval(pov
+ 4, this->version
);
2044 elfcpp::Swap_unaligned
<32, true>::writeval(pov
+ 6, len
- (4 + 2 + 4));
2048 elfcpp::Swap_unaligned
<32, false>::writeval(pov
, len
- 4);
2049 elfcpp::Swap_unaligned
<16, false>::writeval(pov
+ 4, this->version
);
2050 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 6, len
- (4 + 2 + 4));
2053 *pov
++ = 1; // minimum_instruction_length
2054 *pov
++ = 0; // default_is_stmt
2055 *pov
++ = 0; // line_base
2056 *pov
++ = 5; // line_range
2057 *pov
++ = 13; // opcode_base
2058 *pov
++ = 0; // standard_opcode_lengths[1]
2059 *pov
++ = 1; // standard_opcode_lengths[2]
2060 *pov
++ = 1; // standard_opcode_lengths[3]
2061 *pov
++ = 1; // standard_opcode_lengths[4]
2062 *pov
++ = 1; // standard_opcode_lengths[5]
2063 *pov
++ = 0; // standard_opcode_lengths[6]
2064 *pov
++ = 0; // standard_opcode_lengths[7]
2065 *pov
++ = 0; // standard_opcode_lengths[8]
2066 *pov
++ = 1; // standard_opcode_lengths[9]
2067 *pov
++ = 0; // standard_opcode_lengths[10]
2068 *pov
++ = 0; // standard_opcode_lengths[11]
2069 *pov
++ = 1; // standard_opcode_lengths[12]
2070 *pov
++ = 0; // include_directories (empty)
2071 *pov
++ = 0; // filenames (empty)
2073 // Some consumers don't check the header_length field, and simply
2074 // start reading the line number program immediately following the
2075 // header. For those consumers, we fill the remainder of the free
2076 // space with DW_LNS_set_basic_block opcodes. These are effectively
2077 // no-ops: the resulting line table program will not create any rows.
2078 if (pov
< oview
+ len
)
2079 memset(pov
, elfcpp::DW_LNS_set_basic_block
, oview
+ len
- pov
);
2081 of
->write_output_view(off
, len
, oview
);
2084 // Output_section::Input_section methods.
2086 // Return the current data size. For an input section we store the size here.
2087 // For an Output_section_data, we have to ask it for the size.
2090 Output_section::Input_section::current_data_size() const
2092 if (this->is_input_section())
2093 return this->u1_
.data_size
;
2096 this->u2_
.posd
->pre_finalize_data_size();
2097 return this->u2_
.posd
->current_data_size();
2101 // Return the data size. For an input section we store the size here.
2102 // For an Output_section_data, we have to ask it for the size.
2105 Output_section::Input_section::data_size() const
2107 if (this->is_input_section())
2108 return this->u1_
.data_size
;
2110 return this->u2_
.posd
->data_size();
2113 // Return the object for an input section.
2116 Output_section::Input_section::relobj() const
2118 if (this->is_input_section())
2119 return this->u2_
.object
;
2120 else if (this->is_merge_section())
2122 gold_assert(this->u2_
.pomb
->first_relobj() != NULL
);
2123 return this->u2_
.pomb
->first_relobj();
2125 else if (this->is_relaxed_input_section())
2126 return this->u2_
.poris
->relobj();
2131 // Return the input section index for an input section.
2134 Output_section::Input_section::shndx() const
2136 if (this->is_input_section())
2137 return this->shndx_
;
2138 else if (this->is_merge_section())
2140 gold_assert(this->u2_
.pomb
->first_relobj() != NULL
);
2141 return this->u2_
.pomb
->first_shndx();
2143 else if (this->is_relaxed_input_section())
2144 return this->u2_
.poris
->shndx();
2149 // Set the address and file offset.
2152 Output_section::Input_section::set_address_and_file_offset(
2155 off_t section_file_offset
)
2157 if (this->is_input_section())
2158 this->u2_
.object
->set_section_offset(this->shndx_
,
2159 file_offset
- section_file_offset
);
2161 this->u2_
.posd
->set_address_and_file_offset(address
, file_offset
);
2164 // Reset the address and file offset.
2167 Output_section::Input_section::reset_address_and_file_offset()
2169 if (!this->is_input_section())
2170 this->u2_
.posd
->reset_address_and_file_offset();
2173 // Finalize the data size.
2176 Output_section::Input_section::finalize_data_size()
2178 if (!this->is_input_section())
2179 this->u2_
.posd
->finalize_data_size();
2182 // Try to turn an input offset into an output offset. We want to
2183 // return the output offset relative to the start of this
2184 // Input_section in the output section.
2187 Output_section::Input_section::output_offset(
2188 const Relobj
* object
,
2190 section_offset_type offset
,
2191 section_offset_type
* poutput
) const
2193 if (!this->is_input_section())
2194 return this->u2_
.posd
->output_offset(object
, shndx
, offset
, poutput
);
2197 if (this->shndx_
!= shndx
|| this->u2_
.object
!= object
)
2204 // Write out the data. We don't have to do anything for an input
2205 // section--they are handled via Object::relocate--but this is where
2206 // we write out the data for an Output_section_data.
2209 Output_section::Input_section::write(Output_file
* of
)
2211 if (!this->is_input_section())
2212 this->u2_
.posd
->write(of
);
2215 // Write the data to a buffer. As for write(), we don't have to do
2216 // anything for an input section.
2219 Output_section::Input_section::write_to_buffer(unsigned char* buffer
)
2221 if (!this->is_input_section())
2222 this->u2_
.posd
->write_to_buffer(buffer
);
2225 // Print to a map file.
2228 Output_section::Input_section::print_to_mapfile(Mapfile
* mapfile
) const
2230 switch (this->shndx_
)
2232 case OUTPUT_SECTION_CODE
:
2233 case MERGE_DATA_SECTION_CODE
:
2234 case MERGE_STRING_SECTION_CODE
:
2235 this->u2_
.posd
->print_to_mapfile(mapfile
);
2238 case RELAXED_INPUT_SECTION_CODE
:
2240 Output_relaxed_input_section
* relaxed_section
=
2241 this->relaxed_input_section();
2242 mapfile
->print_input_section(relaxed_section
->relobj(),
2243 relaxed_section
->shndx());
2247 mapfile
->print_input_section(this->u2_
.object
, this->shndx_
);
2252 // Output_section methods.
2254 // Construct an Output_section. NAME will point into a Stringpool.
2256 Output_section::Output_section(const char* name
, elfcpp::Elf_Word type
,
2257 elfcpp::Elf_Xword flags
)
2262 link_section_(NULL
),
2264 info_section_(NULL
),
2269 order_(ORDER_INVALID
),
2274 first_input_offset_(0),
2276 postprocessing_buffer_(NULL
),
2277 needs_symtab_index_(false),
2278 needs_dynsym_index_(false),
2279 should_link_to_symtab_(false),
2280 should_link_to_dynsym_(false),
2281 after_input_sections_(false),
2282 requires_postprocessing_(false),
2283 found_in_sections_clause_(false),
2284 has_load_address_(false),
2285 info_uses_section_index_(false),
2286 input_section_order_specified_(false),
2287 may_sort_attached_input_sections_(false),
2288 must_sort_attached_input_sections_(false),
2289 attached_input_sections_are_sorted_(false),
2291 is_small_section_(false),
2292 is_large_section_(false),
2293 generate_code_fills_at_write_(false),
2294 is_entsize_zero_(false),
2295 section_offsets_need_adjustment_(false),
2297 always_keeps_input_sections_(false),
2298 has_fixed_layout_(false),
2299 is_patch_space_allowed_(false),
2300 is_unique_segment_(false),
2302 extra_segment_flags_(0),
2303 segment_alignment_(0),
2305 lookup_maps_(new Output_section_lookup_maps
),
2307 free_space_fill_(NULL
),
2310 // An unallocated section has no address. Forcing this means that
2311 // we don't need special treatment for symbols defined in debug
2313 if ((flags
& elfcpp::SHF_ALLOC
) == 0)
2314 this->set_address(0);
2317 Output_section::~Output_section()
2319 delete this->checkpoint_
;
2322 // Set the entry size.
2325 Output_section::set_entsize(uint64_t v
)
2327 if (this->is_entsize_zero_
)
2329 else if (this->entsize_
== 0)
2331 else if (this->entsize_
!= v
)
2334 this->is_entsize_zero_
= 1;
2338 // Add the input section SHNDX, with header SHDR, named SECNAME, in
2339 // OBJECT, to the Output_section. RELOC_SHNDX is the index of a
2340 // relocation section which applies to this section, or 0 if none, or
2341 // -1U if more than one. Return the offset of the input section
2342 // within the output section. Return -1 if the input section will
2343 // receive special handling. In the normal case we don't always keep
2344 // track of input sections for an Output_section. Instead, each
2345 // Object keeps track of the Output_section for each of its input
2346 // sections. However, if HAVE_SECTIONS_SCRIPT is true, we do keep
2347 // track of input sections here; this is used when SECTIONS appears in
2350 template<int size
, bool big_endian
>
2352 Output_section::add_input_section(Layout
* layout
,
2353 Sized_relobj_file
<size
, big_endian
>* object
,
2355 const char* secname
,
2356 const elfcpp::Shdr
<size
, big_endian
>& shdr
,
2357 unsigned int reloc_shndx
,
2358 bool have_sections_script
)
2360 elfcpp::Elf_Xword addralign
= shdr
.get_sh_addralign();
2361 if ((addralign
& (addralign
- 1)) != 0)
2363 object
->error(_("invalid alignment %lu for section \"%s\""),
2364 static_cast<unsigned long>(addralign
), secname
);
2368 if (addralign
> this->addralign_
)
2369 this->addralign_
= addralign
;
2371 typename
elfcpp::Elf_types
<size
>::Elf_WXword sh_flags
= shdr
.get_sh_flags();
2372 uint64_t entsize
= shdr
.get_sh_entsize();
2374 // .debug_str is a mergeable string section, but is not always so
2375 // marked by compilers. Mark manually here so we can optimize.
2376 if (strcmp(secname
, ".debug_str") == 0)
2378 sh_flags
|= (elfcpp::SHF_MERGE
| elfcpp::SHF_STRINGS
);
2382 this->update_flags_for_input_section(sh_flags
);
2383 this->set_entsize(entsize
);
2385 // If this is a SHF_MERGE section, we pass all the input sections to
2386 // a Output_data_merge. We don't try to handle relocations for such
2387 // a section. We don't try to handle empty merge sections--they
2388 // mess up the mappings, and are useless anyhow.
2389 // FIXME: Need to handle merge sections during incremental update.
2390 if ((sh_flags
& elfcpp::SHF_MERGE
) != 0
2392 && shdr
.get_sh_size() > 0
2393 && !parameters
->incremental())
2395 // Keep information about merged input sections for rebuilding fast
2396 // lookup maps if we have sections-script or we do relaxation.
2397 bool keeps_input_sections
= (this->always_keeps_input_sections_
2398 || have_sections_script
2399 || parameters
->target().may_relax());
2401 if (this->add_merge_input_section(object
, shndx
, sh_flags
, entsize
,
2402 addralign
, keeps_input_sections
))
2404 // Tell the relocation routines that they need to call the
2405 // output_offset method to determine the final address.
2410 section_size_type input_section_size
= shdr
.get_sh_size();
2411 section_size_type uncompressed_size
;
2412 if (object
->section_is_compressed(shndx
, &uncompressed_size
))
2413 input_section_size
= uncompressed_size
;
2415 off_t offset_in_section
;
2417 if (this->has_fixed_layout())
2419 // For incremental updates, find a chunk of unused space in the section.
2420 offset_in_section
= this->free_list_
.allocate(input_section_size
,
2422 if (offset_in_section
== -1)
2423 gold_fallback(_("out of patch space in section %s; "
2424 "relink with --incremental-full"),
2426 return offset_in_section
;
2429 offset_in_section
= this->current_data_size_for_child();
2430 off_t aligned_offset_in_section
= align_address(offset_in_section
,
2432 this->set_current_data_size_for_child(aligned_offset_in_section
2433 + input_section_size
);
2435 // Determine if we want to delay code-fill generation until the output
2436 // section is written. When the target is relaxing, we want to delay fill
2437 // generating to avoid adjusting them during relaxation. Also, if we are
2438 // sorting input sections we must delay fill generation.
2439 if (!this->generate_code_fills_at_write_
2440 && !have_sections_script
2441 && (sh_flags
& elfcpp::SHF_EXECINSTR
) != 0
2442 && parameters
->target().has_code_fill()
2443 && (parameters
->target().may_relax()
2444 || layout
->is_section_ordering_specified()))
2446 gold_assert(this->fills_
.empty());
2447 this->generate_code_fills_at_write_
= true;
2450 if (aligned_offset_in_section
> offset_in_section
2451 && !this->generate_code_fills_at_write_
2452 && !have_sections_script
2453 && (sh_flags
& elfcpp::SHF_EXECINSTR
) != 0
2454 && parameters
->target().has_code_fill())
2456 // We need to add some fill data. Using fill_list_ when
2457 // possible is an optimization, since we will often have fill
2458 // sections without input sections.
2459 off_t fill_len
= aligned_offset_in_section
- offset_in_section
;
2460 if (this->input_sections_
.empty())
2461 this->fills_
.push_back(Fill(offset_in_section
, fill_len
));
2464 std::string
fill_data(parameters
->target().code_fill(fill_len
));
2465 Output_data_const
* odc
= new Output_data_const(fill_data
, 1);
2466 this->input_sections_
.push_back(Input_section(odc
));
2470 // We need to keep track of this section if we are already keeping
2471 // track of sections, or if we are relaxing. Also, if this is a
2472 // section which requires sorting, or which may require sorting in
2473 // the future, we keep track of the sections. If the
2474 // --section-ordering-file option is used to specify the order of
2475 // sections, we need to keep track of sections.
2476 if (this->always_keeps_input_sections_
2477 || have_sections_script
2478 || !this->input_sections_
.empty()
2479 || this->may_sort_attached_input_sections()
2480 || this->must_sort_attached_input_sections()
2481 || parameters
->options().user_set_Map()
2482 || parameters
->target().may_relax()
2483 || layout
->is_section_ordering_specified())
2485 Input_section
isecn(object
, shndx
, input_section_size
, addralign
);
2486 /* If section ordering is requested by specifying a ordering file,
2487 using --section-ordering-file, match the section name with
2489 if (parameters
->options().section_ordering_file())
2491 unsigned int section_order_index
=
2492 layout
->find_section_order_index(std::string(secname
));
2493 if (section_order_index
!= 0)
2495 isecn
.set_section_order_index(section_order_index
);
2496 this->set_input_section_order_specified();
2499 this->input_sections_
.push_back(isecn
);
2502 return aligned_offset_in_section
;
2505 // Add arbitrary data to an output section.
2508 Output_section::add_output_section_data(Output_section_data
* posd
)
2510 Input_section
inp(posd
);
2511 this->add_output_section_data(&inp
);
2513 if (posd
->is_data_size_valid())
2515 off_t offset_in_section
;
2516 if (this->has_fixed_layout())
2518 // For incremental updates, find a chunk of unused space.
2519 offset_in_section
= this->free_list_
.allocate(posd
->data_size(),
2520 posd
->addralign(), 0);
2521 if (offset_in_section
== -1)
2522 gold_fallback(_("out of patch space in section %s; "
2523 "relink with --incremental-full"),
2525 // Finalize the address and offset now.
2526 uint64_t addr
= this->address();
2527 off_t offset
= this->offset();
2528 posd
->set_address_and_file_offset(addr
+ offset_in_section
,
2529 offset
+ offset_in_section
);
2533 offset_in_section
= this->current_data_size_for_child();
2534 off_t aligned_offset_in_section
= align_address(offset_in_section
,
2536 this->set_current_data_size_for_child(aligned_offset_in_section
2537 + posd
->data_size());
2540 else if (this->has_fixed_layout())
2542 // For incremental updates, arrange for the data to have a fixed layout.
2543 // This will mean that additions to the data must be allocated from
2544 // free space within the containing output section.
2545 uint64_t addr
= this->address();
2546 posd
->set_address(addr
);
2547 posd
->set_file_offset(0);
2548 // FIXME: This should eventually be unreachable.
2549 // gold_unreachable();
2553 // Add a relaxed input section.
2556 Output_section::add_relaxed_input_section(Layout
* layout
,
2557 Output_relaxed_input_section
* poris
,
2558 const std::string
& name
)
2560 Input_section
inp(poris
);
2562 // If the --section-ordering-file option is used to specify the order of
2563 // sections, we need to keep track of sections.
2564 if (layout
->is_section_ordering_specified())
2566 unsigned int section_order_index
=
2567 layout
->find_section_order_index(name
);
2568 if (section_order_index
!= 0)
2570 inp
.set_section_order_index(section_order_index
);
2571 this->set_input_section_order_specified();
2575 this->add_output_section_data(&inp
);
2576 if (this->lookup_maps_
->is_valid())
2577 this->lookup_maps_
->add_relaxed_input_section(poris
->relobj(),
2578 poris
->shndx(), poris
);
2580 // For a relaxed section, we use the current data size. Linker scripts
2581 // get all the input sections, including relaxed one from an output
2582 // section and add them back to the same output section to compute the
2583 // output section size. If we do not account for sizes of relaxed input
2584 // sections, an output section would be incorrectly sized.
2585 off_t offset_in_section
= this->current_data_size_for_child();
2586 off_t aligned_offset_in_section
= align_address(offset_in_section
,
2587 poris
->addralign());
2588 this->set_current_data_size_for_child(aligned_offset_in_section
2589 + poris
->current_data_size());
2592 // Add arbitrary data to an output section by Input_section.
2595 Output_section::add_output_section_data(Input_section
* inp
)
2597 if (this->input_sections_
.empty())
2598 this->first_input_offset_
= this->current_data_size_for_child();
2600 this->input_sections_
.push_back(*inp
);
2602 uint64_t addralign
= inp
->addralign();
2603 if (addralign
> this->addralign_
)
2604 this->addralign_
= addralign
;
2606 inp
->set_output_section(this);
2609 // Add a merge section to an output section.
2612 Output_section::add_output_merge_section(Output_section_data
* posd
,
2613 bool is_string
, uint64_t entsize
)
2615 Input_section
inp(posd
, is_string
, entsize
);
2616 this->add_output_section_data(&inp
);
2619 // Add an input section to a SHF_MERGE section.
2622 Output_section::add_merge_input_section(Relobj
* object
, unsigned int shndx
,
2623 uint64_t flags
, uint64_t entsize
,
2625 bool keeps_input_sections
)
2627 // We cannot merge sections with entsize == 0.
2631 bool is_string
= (flags
& elfcpp::SHF_STRINGS
) != 0;
2633 // We cannot restore merged input section states.
2634 gold_assert(this->checkpoint_
== NULL
);
2636 // Look up merge sections by required properties.
2637 // Currently, we only invalidate the lookup maps in script processing
2638 // and relaxation. We should not have done either when we reach here.
2639 // So we assume that the lookup maps are valid to simply code.
2640 gold_assert(this->lookup_maps_
->is_valid());
2641 Merge_section_properties
msp(is_string
, entsize
, addralign
);
2642 Output_merge_base
* pomb
= this->lookup_maps_
->find_merge_section(msp
);
2643 bool is_new
= false;
2646 gold_assert(pomb
->is_string() == is_string
2647 && pomb
->entsize() == entsize
2648 && pomb
->addralign() == addralign
);
2652 // Create a new Output_merge_data or Output_merge_string_data.
2654 pomb
= new Output_merge_data(entsize
, addralign
);
2660 pomb
= new Output_merge_string
<char>(addralign
);
2663 pomb
= new Output_merge_string
<uint16_t>(addralign
);
2666 pomb
= new Output_merge_string
<uint32_t>(addralign
);
2672 // If we need to do script processing or relaxation, we need to keep
2673 // the original input sections to rebuild the fast lookup maps.
2674 if (keeps_input_sections
)
2675 pomb
->set_keeps_input_sections();
2679 if (pomb
->add_input_section(object
, shndx
))
2681 // Add new merge section to this output section and link merge
2682 // section properties to new merge section in map.
2685 this->add_output_merge_section(pomb
, is_string
, entsize
);
2686 this->lookup_maps_
->add_merge_section(msp
, pomb
);
2693 // If add_input_section failed, delete new merge section to avoid
2694 // exporting empty merge sections in Output_section::get_input_section.
2701 // Build a relaxation map to speed up relaxation of existing input sections.
2702 // Look up to the first LIMIT elements in INPUT_SECTIONS.
2705 Output_section::build_relaxation_map(
2706 const Input_section_list
& input_sections
,
2708 Relaxation_map
* relaxation_map
) const
2710 for (size_t i
= 0; i
< limit
; ++i
)
2712 const Input_section
& is(input_sections
[i
]);
2713 if (is
.is_input_section() || is
.is_relaxed_input_section())
2715 Section_id
sid(is
.relobj(), is
.shndx());
2716 (*relaxation_map
)[sid
] = i
;
2721 // Convert regular input sections in INPUT_SECTIONS into relaxed input
2722 // sections in RELAXED_SECTIONS. MAP is a prebuilt map from section id
2723 // indices of INPUT_SECTIONS.
2726 Output_section::convert_input_sections_in_list_to_relaxed_sections(
2727 const std::vector
<Output_relaxed_input_section
*>& relaxed_sections
,
2728 const Relaxation_map
& map
,
2729 Input_section_list
* input_sections
)
2731 for (size_t i
= 0; i
< relaxed_sections
.size(); ++i
)
2733 Output_relaxed_input_section
* poris
= relaxed_sections
[i
];
2734 Section_id
sid(poris
->relobj(), poris
->shndx());
2735 Relaxation_map::const_iterator p
= map
.find(sid
);
2736 gold_assert(p
!= map
.end());
2737 gold_assert((*input_sections
)[p
->second
].is_input_section());
2739 // Remember section order index of original input section
2740 // if it is set. Copy it to the relaxed input section.
2742 (*input_sections
)[p
->second
].section_order_index();
2743 (*input_sections
)[p
->second
] = Input_section(poris
);
2744 (*input_sections
)[p
->second
].set_section_order_index(soi
);
2748 // Convert regular input sections into relaxed input sections. RELAXED_SECTIONS
2749 // is a vector of pointers to Output_relaxed_input_section or its derived
2750 // classes. The relaxed sections must correspond to existing input sections.
2753 Output_section::convert_input_sections_to_relaxed_sections(
2754 const std::vector
<Output_relaxed_input_section
*>& relaxed_sections
)
2756 gold_assert(parameters
->target().may_relax());
2758 // We want to make sure that restore_states does not undo the effect of
2759 // this. If there is no checkpoint active, just search the current
2760 // input section list and replace the sections there. If there is
2761 // a checkpoint, also replace the sections there.
2763 // By default, we look at the whole list.
2764 size_t limit
= this->input_sections_
.size();
2766 if (this->checkpoint_
!= NULL
)
2768 // Replace input sections with relaxed input section in the saved
2769 // copy of the input section list.
2770 if (this->checkpoint_
->input_sections_saved())
2773 this->build_relaxation_map(
2774 *(this->checkpoint_
->input_sections()),
2775 this->checkpoint_
->input_sections()->size(),
2777 this->convert_input_sections_in_list_to_relaxed_sections(
2780 this->checkpoint_
->input_sections());
2784 // We have not copied the input section list yet. Instead, just
2785 // look at the portion that would be saved.
2786 limit
= this->checkpoint_
->input_sections_size();
2790 // Convert input sections in input_section_list.
2792 this->build_relaxation_map(this->input_sections_
, limit
, &map
);
2793 this->convert_input_sections_in_list_to_relaxed_sections(
2796 &this->input_sections_
);
2798 // Update fast look-up map.
2799 if (this->lookup_maps_
->is_valid())
2800 for (size_t i
= 0; i
< relaxed_sections
.size(); ++i
)
2802 Output_relaxed_input_section
* poris
= relaxed_sections
[i
];
2803 this->lookup_maps_
->add_relaxed_input_section(poris
->relobj(),
2804 poris
->shndx(), poris
);
2808 // Update the output section flags based on input section flags.
2811 Output_section::update_flags_for_input_section(elfcpp::Elf_Xword flags
)
2813 // If we created the section with SHF_ALLOC clear, we set the
2814 // address. If we are now setting the SHF_ALLOC flag, we need to
2816 if ((this->flags_
& elfcpp::SHF_ALLOC
) == 0
2817 && (flags
& elfcpp::SHF_ALLOC
) != 0)
2818 this->mark_address_invalid();
2820 this->flags_
|= (flags
2821 & (elfcpp::SHF_WRITE
2823 | elfcpp::SHF_EXECINSTR
));
2825 if ((flags
& elfcpp::SHF_MERGE
) == 0)
2826 this->flags_
&=~ elfcpp::SHF_MERGE
;
2829 if (this->current_data_size_for_child() == 0)
2830 this->flags_
|= elfcpp::SHF_MERGE
;
2833 if ((flags
& elfcpp::SHF_STRINGS
) == 0)
2834 this->flags_
&=~ elfcpp::SHF_STRINGS
;
2837 if (this->current_data_size_for_child() == 0)
2838 this->flags_
|= elfcpp::SHF_STRINGS
;
2842 // Find the merge section into which an input section with index SHNDX in
2843 // OBJECT has been added. Return NULL if none found.
2845 const Output_section_data
*
2846 Output_section::find_merge_section(const Relobj
* object
,
2847 unsigned int shndx
) const
2849 return object
->find_merge_section(shndx
);
2852 // Build the lookup maps for relaxed sections. This needs
2853 // to be declared as a const method so that it is callable with a const
2854 // Output_section pointer. The method only updates states of the maps.
2857 Output_section::build_lookup_maps() const
2859 this->lookup_maps_
->clear();
2860 for (Input_section_list::const_iterator p
= this->input_sections_
.begin();
2861 p
!= this->input_sections_
.end();
2864 if (p
->is_relaxed_input_section())
2866 Output_relaxed_input_section
* poris
= p
->relaxed_input_section();
2867 this->lookup_maps_
->add_relaxed_input_section(poris
->relobj(),
2868 poris
->shndx(), poris
);
2873 // Find an relaxed input section corresponding to an input section
2874 // in OBJECT with index SHNDX.
2876 const Output_relaxed_input_section
*
2877 Output_section::find_relaxed_input_section(const Relobj
* object
,
2878 unsigned int shndx
) const
2880 if (!this->lookup_maps_
->is_valid())
2881 this->build_lookup_maps();
2882 return this->lookup_maps_
->find_relaxed_input_section(object
, shndx
);
2885 // Given an address OFFSET relative to the start of input section
2886 // SHNDX in OBJECT, return whether this address is being included in
2887 // the final link. This should only be called if SHNDX in OBJECT has
2888 // a special mapping.
2891 Output_section::is_input_address_mapped(const Relobj
* object
,
2895 // Look at the Output_section_data_maps first.
2896 const Output_section_data
* posd
= this->find_merge_section(object
, shndx
);
2898 posd
= this->find_relaxed_input_section(object
, shndx
);
2902 section_offset_type output_offset
;
2903 bool found
= posd
->output_offset(object
, shndx
, offset
, &output_offset
);
2904 // By default we assume that the address is mapped. See comment at the
2908 return output_offset
!= -1;
2911 // Fall back to the slow look-up.
2912 for (Input_section_list::const_iterator p
= this->input_sections_
.begin();
2913 p
!= this->input_sections_
.end();
2916 section_offset_type output_offset
;
2917 if (p
->output_offset(object
, shndx
, offset
, &output_offset
))
2918 return output_offset
!= -1;
2921 // By default we assume that the address is mapped. This should
2922 // only be called after we have passed all sections to Layout. At
2923 // that point we should know what we are discarding.
2927 // Given an address OFFSET relative to the start of input section
2928 // SHNDX in object OBJECT, return the output offset relative to the
2929 // start of the input section in the output section. This should only
2930 // be called if SHNDX in OBJECT has a special mapping.
2933 Output_section::output_offset(const Relobj
* object
, unsigned int shndx
,
2934 section_offset_type offset
) const
2936 // This can only be called meaningfully when we know the data size
2938 gold_assert(this->is_data_size_valid());
2940 // Look at the Output_section_data_maps first.
2941 const Output_section_data
* posd
= this->find_merge_section(object
, shndx
);
2943 posd
= this->find_relaxed_input_section(object
, shndx
);
2946 section_offset_type output_offset
;
2947 bool found
= posd
->output_offset(object
, shndx
, offset
, &output_offset
);
2949 return output_offset
;
2952 // Fall back to the slow look-up.
2953 for (Input_section_list::const_iterator p
= this->input_sections_
.begin();
2954 p
!= this->input_sections_
.end();
2957 section_offset_type output_offset
;
2958 if (p
->output_offset(object
, shndx
, offset
, &output_offset
))
2959 return output_offset
;
2964 // Return the output virtual address of OFFSET relative to the start
2965 // of input section SHNDX in object OBJECT.
2968 Output_section::output_address(const Relobj
* object
, unsigned int shndx
,
2971 uint64_t addr
= this->address() + this->first_input_offset_
;
2973 // Look at the Output_section_data_maps first.
2974 const Output_section_data
* posd
= this->find_merge_section(object
, shndx
);
2976 posd
= this->find_relaxed_input_section(object
, shndx
);
2977 if (posd
!= NULL
&& posd
->is_address_valid())
2979 section_offset_type output_offset
;
2980 bool found
= posd
->output_offset(object
, shndx
, offset
, &output_offset
);
2982 return posd
->address() + output_offset
;
2985 // Fall back to the slow look-up.
2986 for (Input_section_list::const_iterator p
= this->input_sections_
.begin();
2987 p
!= this->input_sections_
.end();
2990 addr
= align_address(addr
, p
->addralign());
2991 section_offset_type output_offset
;
2992 if (p
->output_offset(object
, shndx
, offset
, &output_offset
))
2994 if (output_offset
== -1)
2996 return addr
+ output_offset
;
2998 addr
+= p
->data_size();
3001 // If we get here, it means that we don't know the mapping for this
3002 // input section. This might happen in principle if
3003 // add_input_section were called before add_output_section_data.
3004 // But it should never actually happen.
3009 // Find the output address of the start of the merged section for
3010 // input section SHNDX in object OBJECT.
3013 Output_section::find_starting_output_address(const Relobj
* object
,
3015 uint64_t* paddr
) const
3017 const Output_section_data
* data
= this->find_merge_section(object
, shndx
);
3021 // FIXME: This becomes a bottle-neck if we have many relaxed sections.
3022 // Looking up the merge section map does not always work as we sometimes
3023 // find a merge section without its address set.
3024 uint64_t addr
= this->address() + this->first_input_offset_
;
3025 for (Input_section_list::const_iterator p
= this->input_sections_
.begin();
3026 p
!= this->input_sections_
.end();
3029 addr
= align_address(addr
, p
->addralign());
3031 // It would be nice if we could use the existing output_offset
3032 // method to get the output offset of input offset 0.
3033 // Unfortunately we don't know for sure that input offset 0 is
3035 if (!p
->is_input_section() && p
->output_section_data() == data
)
3041 addr
+= p
->data_size();
3044 // We couldn't find a merge output section for this input section.
3048 // Update the data size of an Output_section.
3051 Output_section::update_data_size()
3053 if (this->input_sections_
.empty())
3056 if (this->must_sort_attached_input_sections()
3057 || this->input_section_order_specified())
3058 this->sort_attached_input_sections();
3060 off_t off
= this->first_input_offset_
;
3061 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3062 p
!= this->input_sections_
.end();
3065 off
= align_address(off
, p
->addralign());
3066 off
+= p
->current_data_size();
3069 this->set_current_data_size_for_child(off
);
3072 // Set the data size of an Output_section. This is where we handle
3073 // setting the addresses of any Output_section_data objects.
3076 Output_section::set_final_data_size()
3080 if (this->input_sections_
.empty())
3081 data_size
= this->current_data_size_for_child();
3084 if (this->must_sort_attached_input_sections()
3085 || this->input_section_order_specified())
3086 this->sort_attached_input_sections();
3088 uint64_t address
= this->address();
3089 off_t startoff
= this->offset();
3090 off_t off
= startoff
+ this->first_input_offset_
;
3091 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3092 p
!= this->input_sections_
.end();
3095 off
= align_address(off
, p
->addralign());
3096 p
->set_address_and_file_offset(address
+ (off
- startoff
), off
,
3098 off
+= p
->data_size();
3100 data_size
= off
- startoff
;
3103 // For full incremental links, we want to allocate some patch space
3104 // in most sections for subsequent incremental updates.
3105 if (this->is_patch_space_allowed_
&& parameters
->incremental_full())
3107 double pct
= parameters
->options().incremental_patch();
3108 size_t extra
= static_cast<size_t>(data_size
* pct
);
3109 if (this->free_space_fill_
!= NULL
3110 && this->free_space_fill_
->minimum_hole_size() > extra
)
3111 extra
= this->free_space_fill_
->minimum_hole_size();
3112 off_t new_size
= align_address(data_size
+ extra
, this->addralign());
3113 this->patch_space_
= new_size
- data_size
;
3114 gold_debug(DEBUG_INCREMENTAL
,
3115 "set_final_data_size: %08lx + %08lx: section %s",
3116 static_cast<long>(data_size
),
3117 static_cast<long>(this->patch_space_
),
3119 data_size
= new_size
;
3122 this->set_data_size(data_size
);
3125 // Reset the address and file offset.
3128 Output_section::do_reset_address_and_file_offset()
3130 // An unallocated section has no address. Forcing this means that
3131 // we don't need special treatment for symbols defined in debug
3132 // sections. We do the same in the constructor. This does not
3133 // apply to NOLOAD sections though.
3134 if (((this->flags_
& elfcpp::SHF_ALLOC
) == 0) && !this->is_noload_
)
3135 this->set_address(0);
3137 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3138 p
!= this->input_sections_
.end();
3140 p
->reset_address_and_file_offset();
3142 // Remove any patch space that was added in set_final_data_size.
3143 if (this->patch_space_
> 0)
3145 this->set_current_data_size_for_child(this->current_data_size_for_child()
3146 - this->patch_space_
);
3147 this->patch_space_
= 0;
3151 // Return true if address and file offset have the values after reset.
3154 Output_section::do_address_and_file_offset_have_reset_values() const
3156 if (this->is_offset_valid())
3159 // An unallocated section has address 0 after its construction or a reset.
3160 if ((this->flags_
& elfcpp::SHF_ALLOC
) == 0)
3161 return this->is_address_valid() && this->address() == 0;
3163 return !this->is_address_valid();
3166 // Set the TLS offset. Called only for SHT_TLS sections.
3169 Output_section::do_set_tls_offset(uint64_t tls_base
)
3171 this->tls_offset_
= this->address() - tls_base
;
3174 // In a few cases we need to sort the input sections attached to an
3175 // output section. This is used to implement the type of constructor
3176 // priority ordering implemented by the GNU linker, in which the
3177 // priority becomes part of the section name and the sections are
3178 // sorted by name. We only do this for an output section if we see an
3179 // attached input section matching ".ctors.*", ".dtors.*",
3180 // ".init_array.*" or ".fini_array.*".
3182 class Output_section::Input_section_sort_entry
3185 Input_section_sort_entry()
3186 : input_section_(), index_(-1U), section_name_()
3189 Input_section_sort_entry(const Input_section
& input_section
,
3191 bool must_sort_attached_input_sections
,
3192 const char* output_section_name
)
3193 : input_section_(input_section
), index_(index
), section_name_()
3195 if ((input_section
.is_input_section()
3196 || input_section
.is_relaxed_input_section())
3197 && must_sort_attached_input_sections
)
3199 // This is only called single-threaded from Layout::finalize,
3200 // so it is OK to lock. Unfortunately we have no way to pass
3202 const Task
* dummy_task
= reinterpret_cast<const Task
*>(-1);
3203 Object
* obj
= (input_section
.is_input_section()
3204 ? input_section
.relobj()
3205 : input_section
.relaxed_input_section()->relobj());
3206 Task_lock_obj
<Object
> tl(dummy_task
, obj
);
3208 // This is a slow operation, which should be cached in
3209 // Layout::layout if this becomes a speed problem.
3210 this->section_name_
= obj
->section_name(input_section
.shndx());
3212 else if (input_section
.is_output_section_data()
3213 && must_sort_attached_input_sections
)
3215 // For linker-generated sections, use the output section name.
3216 this->section_name_
.assign(output_section_name
);
3220 // Return the Input_section.
3221 const Input_section
&
3222 input_section() const
3224 gold_assert(this->index_
!= -1U);
3225 return this->input_section_
;
3228 // The index of this entry in the original list. This is used to
3229 // make the sort stable.
3233 gold_assert(this->index_
!= -1U);
3234 return this->index_
;
3237 // The section name.
3239 section_name() const
3241 return this->section_name_
;
3244 // Return true if the section name has a priority. This is assumed
3245 // to be true if it has a dot after the initial dot.
3247 has_priority() const
3249 return this->section_name_
.find('.', 1) != std::string::npos
;
3252 // Return the priority. Believe it or not, gcc encodes the priority
3253 // differently for .ctors/.dtors and .init_array/.fini_array
3256 get_priority() const
3259 if (is_prefix_of(".ctors.", this->section_name_
.c_str())
3260 || is_prefix_of(".dtors.", this->section_name_
.c_str()))
3262 else if (is_prefix_of(".init_array.", this->section_name_
.c_str())
3263 || is_prefix_of(".fini_array.", this->section_name_
.c_str()))
3268 unsigned long prio
= strtoul((this->section_name_
.c_str()
3269 + (is_ctors
? 7 : 12)),
3274 return 65535 - prio
;
3279 // Return true if this an input file whose base name matches
3280 // FILE_NAME. The base name must have an extension of ".o", and
3281 // must be exactly FILE_NAME.o or FILE_NAME, one character, ".o".
3282 // This is to match crtbegin.o as well as crtbeginS.o without
3283 // getting confused by other possibilities. Overall matching the
3284 // file name this way is a dreadful hack, but the GNU linker does it
3285 // in order to better support gcc, and we need to be compatible.
3287 match_file_name(const char* file_name
) const
3289 if (this->input_section_
.is_output_section_data())
3291 return Layout::match_file_name(this->input_section_
.relobj(), file_name
);
3294 // Returns 1 if THIS should appear before S in section order, -1 if S
3295 // appears before THIS and 0 if they are not comparable.
3297 compare_section_ordering(const Input_section_sort_entry
& s
) const
3299 unsigned int this_secn_index
= this->input_section_
.section_order_index();
3300 unsigned int s_secn_index
= s
.input_section().section_order_index();
3301 if (this_secn_index
> 0 && s_secn_index
> 0)
3303 if (this_secn_index
< s_secn_index
)
3305 else if (this_secn_index
> s_secn_index
)
3312 // The Input_section we are sorting.
3313 Input_section input_section_
;
3314 // The index of this Input_section in the original list.
3315 unsigned int index_
;
3316 // The section name if there is one.
3317 std::string section_name_
;
3320 // Return true if S1 should come before S2 in the output section.
3323 Output_section::Input_section_sort_compare::operator()(
3324 const Output_section::Input_section_sort_entry
& s1
,
3325 const Output_section::Input_section_sort_entry
& s2
) const
3327 // crtbegin.o must come first.
3328 bool s1_begin
= s1
.match_file_name("crtbegin");
3329 bool s2_begin
= s2
.match_file_name("crtbegin");
3330 if (s1_begin
|| s2_begin
)
3336 return s1
.index() < s2
.index();
3339 // crtend.o must come last.
3340 bool s1_end
= s1
.match_file_name("crtend");
3341 bool s2_end
= s2
.match_file_name("crtend");
3342 if (s1_end
|| s2_end
)
3348 return s1
.index() < s2
.index();
3351 // A section with a priority follows a section without a priority.
3352 bool s1_has_priority
= s1
.has_priority();
3353 bool s2_has_priority
= s2
.has_priority();
3354 if (s1_has_priority
&& !s2_has_priority
)
3356 if (!s1_has_priority
&& s2_has_priority
)
3359 // Check if a section order exists for these sections through a section
3360 // ordering file. If sequence_num is 0, an order does not exist.
3361 int sequence_num
= s1
.compare_section_ordering(s2
);
3362 if (sequence_num
!= 0)
3363 return sequence_num
== 1;
3365 // Otherwise we sort by name.
3366 int compare
= s1
.section_name().compare(s2
.section_name());
3370 // Otherwise we keep the input order.
3371 return s1
.index() < s2
.index();
3374 // Return true if S1 should come before S2 in an .init_array or .fini_array
3378 Output_section::Input_section_sort_init_fini_compare::operator()(
3379 const Output_section::Input_section_sort_entry
& s1
,
3380 const Output_section::Input_section_sort_entry
& s2
) const
3382 // A section without a priority follows a section with a priority.
3383 // This is the reverse of .ctors and .dtors sections.
3384 bool s1_has_priority
= s1
.has_priority();
3385 bool s2_has_priority
= s2
.has_priority();
3386 if (s1_has_priority
&& !s2_has_priority
)
3388 if (!s1_has_priority
&& s2_has_priority
)
3391 // .ctors and .dtors sections without priority come after
3392 // .init_array and .fini_array sections without priority.
3393 if (!s1_has_priority
3394 && (s1
.section_name() == ".ctors" || s1
.section_name() == ".dtors")
3395 && s1
.section_name() != s2
.section_name())
3397 if (!s2_has_priority
3398 && (s2
.section_name() == ".ctors" || s2
.section_name() == ".dtors")
3399 && s2
.section_name() != s1
.section_name())
3402 // Sort by priority if we can.
3403 if (s1_has_priority
)
3405 unsigned int s1_prio
= s1
.get_priority();
3406 unsigned int s2_prio
= s2
.get_priority();
3407 if (s1_prio
< s2_prio
)
3409 else if (s1_prio
> s2_prio
)
3413 // Check if a section order exists for these sections through a section
3414 // ordering file. If sequence_num is 0, an order does not exist.
3415 int sequence_num
= s1
.compare_section_ordering(s2
);
3416 if (sequence_num
!= 0)
3417 return sequence_num
== 1;
3419 // Otherwise we sort by name.
3420 int compare
= s1
.section_name().compare(s2
.section_name());
3424 // Otherwise we keep the input order.
3425 return s1
.index() < s2
.index();
3428 // Return true if S1 should come before S2. Sections that do not match
3429 // any pattern in the section ordering file are placed ahead of the sections
3430 // that match some pattern.
3433 Output_section::Input_section_sort_section_order_index_compare::operator()(
3434 const Output_section::Input_section_sort_entry
& s1
,
3435 const Output_section::Input_section_sort_entry
& s2
) const
3437 unsigned int s1_secn_index
= s1
.input_section().section_order_index();
3438 unsigned int s2_secn_index
= s2
.input_section().section_order_index();
3440 // Keep input order if section ordering cannot determine order.
3441 if (s1_secn_index
== s2_secn_index
)
3442 return s1
.index() < s2
.index();
3444 return s1_secn_index
< s2_secn_index
;
3447 // Return true if S1 should come before S2. This is the sort comparison
3448 // function for .text to sort sections with prefixes
3449 // .text.{unlikely,exit,startup,hot} before other sections.
3452 Output_section::Input_section_sort_section_prefix_special_ordering_compare
3454 const Output_section::Input_section_sort_entry
& s1
,
3455 const Output_section::Input_section_sort_entry
& s2
) const
3457 // Some input section names have special ordering requirements.
3458 int o1
= Layout::special_ordering_of_input_section(s1
.section_name().c_str());
3459 int o2
= Layout::special_ordering_of_input_section(s2
.section_name().c_str());
3470 // Keep input order otherwise.
3471 return s1
.index() < s2
.index();
3474 // Return true if S1 should come before S2. This is the sort comparison
3475 // function for sections to sort them by name.
3478 Output_section::Input_section_sort_section_name_compare
3480 const Output_section::Input_section_sort_entry
& s1
,
3481 const Output_section::Input_section_sort_entry
& s2
) const
3484 int compare
= s1
.section_name().compare(s2
.section_name());
3488 // Keep input order otherwise.
3489 return s1
.index() < s2
.index();
3492 // This updates the section order index of input sections according to the
3493 // the order specified in the mapping from Section id to order index.
3496 Output_section::update_section_layout(
3497 const Section_layout_order
* order_map
)
3499 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3500 p
!= this->input_sections_
.end();
3503 if (p
->is_input_section()
3504 || p
->is_relaxed_input_section())
3506 Relobj
* obj
= (p
->is_input_section()
3508 : p
->relaxed_input_section()->relobj());
3509 unsigned int shndx
= p
->shndx();
3510 Section_layout_order::const_iterator it
3511 = order_map
->find(Section_id(obj
, shndx
));
3512 if (it
== order_map
->end())
3514 unsigned int section_order_index
= it
->second
;
3515 if (section_order_index
!= 0)
3517 p
->set_section_order_index(section_order_index
);
3518 this->set_input_section_order_specified();
3524 // Sort the input sections attached to an output section.
3527 Output_section::sort_attached_input_sections()
3529 if (this->attached_input_sections_are_sorted_
)
3532 if (this->checkpoint_
!= NULL
3533 && !this->checkpoint_
->input_sections_saved())
3534 this->checkpoint_
->save_input_sections();
3536 // The only thing we know about an input section is the object and
3537 // the section index. We need the section name. Recomputing this
3538 // is slow but this is an unusual case. If this becomes a speed
3539 // problem we can cache the names as required in Layout::layout.
3541 // We start by building a larger vector holding a copy of each
3542 // Input_section, plus its current index in the list and its name.
3543 std::vector
<Input_section_sort_entry
> sort_list
;
3546 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3547 p
!= this->input_sections_
.end();
3549 sort_list
.push_back(Input_section_sort_entry(*p
, i
,
3550 this->must_sort_attached_input_sections(),
3553 // Sort the input sections.
3554 if (this->must_sort_attached_input_sections())
3556 if (this->type() == elfcpp::SHT_PREINIT_ARRAY
3557 || this->type() == elfcpp::SHT_INIT_ARRAY
3558 || this->type() == elfcpp::SHT_FINI_ARRAY
)
3559 std::sort(sort_list
.begin(), sort_list
.end(),
3560 Input_section_sort_init_fini_compare());
3561 else if (strcmp(parameters
->options().sort_section(), "name") == 0)
3562 std::sort(sort_list
.begin(), sort_list
.end(),
3563 Input_section_sort_section_name_compare());
3564 else if (strcmp(this->name(), ".text") == 0)
3565 std::sort(sort_list
.begin(), sort_list
.end(),
3566 Input_section_sort_section_prefix_special_ordering_compare());
3568 std::sort(sort_list
.begin(), sort_list
.end(),
3569 Input_section_sort_compare());
3573 gold_assert(this->input_section_order_specified());
3574 std::sort(sort_list
.begin(), sort_list
.end(),
3575 Input_section_sort_section_order_index_compare());
3578 // Copy the sorted input sections back to our list.
3579 this->input_sections_
.clear();
3580 for (std::vector
<Input_section_sort_entry
>::iterator p
= sort_list
.begin();
3581 p
!= sort_list
.end();
3583 this->input_sections_
.push_back(p
->input_section());
3586 // Remember that we sorted the input sections, since we might get
3588 this->attached_input_sections_are_sorted_
= true;
3591 // Write the section header to *OSHDR.
3593 template<int size
, bool big_endian
>
3595 Output_section::write_header(const Layout
* layout
,
3596 const Stringpool
* secnamepool
,
3597 elfcpp::Shdr_write
<size
, big_endian
>* oshdr
) const
3599 oshdr
->put_sh_name(secnamepool
->get_offset(this->name_
));
3600 oshdr
->put_sh_type(this->type_
);
3602 elfcpp::Elf_Xword flags
= this->flags_
;
3603 if (this->info_section_
!= NULL
&& this->info_uses_section_index_
)
3604 flags
|= elfcpp::SHF_INFO_LINK
;
3605 oshdr
->put_sh_flags(flags
);
3607 oshdr
->put_sh_addr(this->address());
3608 oshdr
->put_sh_offset(this->offset());
3609 oshdr
->put_sh_size(this->data_size());
3610 if (this->link_section_
!= NULL
)
3611 oshdr
->put_sh_link(this->link_section_
->out_shndx());
3612 else if (this->should_link_to_symtab_
)
3613 oshdr
->put_sh_link(layout
->symtab_section_shndx());
3614 else if (this->should_link_to_dynsym_
)
3615 oshdr
->put_sh_link(layout
->dynsym_section()->out_shndx());
3617 oshdr
->put_sh_link(this->link_
);
3619 elfcpp::Elf_Word info
;
3620 if (this->info_section_
!= NULL
)
3622 if (this->info_uses_section_index_
)
3623 info
= this->info_section_
->out_shndx();
3625 info
= this->info_section_
->symtab_index();
3627 else if (this->info_symndx_
!= NULL
)
3628 info
= this->info_symndx_
->symtab_index();
3631 oshdr
->put_sh_info(info
);
3633 oshdr
->put_sh_addralign(this->addralign_
);
3634 oshdr
->put_sh_entsize(this->entsize_
);
3637 // Write out the data. For input sections the data is written out by
3638 // Object::relocate, but we have to handle Output_section_data objects
3642 Output_section::do_write(Output_file
* of
)
3644 gold_assert(!this->requires_postprocessing());
3646 // If the target performs relaxation, we delay filler generation until now.
3647 gold_assert(!this->generate_code_fills_at_write_
|| this->fills_
.empty());
3649 off_t output_section_file_offset
= this->offset();
3650 for (Fill_list::iterator p
= this->fills_
.begin();
3651 p
!= this->fills_
.end();
3654 std::string
fill_data(parameters
->target().code_fill(p
->length()));
3655 of
->write(output_section_file_offset
+ p
->section_offset(),
3656 fill_data
.data(), fill_data
.size());
3659 off_t off
= this->offset() + this->first_input_offset_
;
3660 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3661 p
!= this->input_sections_
.end();
3664 off_t aligned_off
= align_address(off
, p
->addralign());
3665 if (this->generate_code_fills_at_write_
&& (off
!= aligned_off
))
3667 size_t fill_len
= aligned_off
- off
;
3668 std::string
fill_data(parameters
->target().code_fill(fill_len
));
3669 of
->write(off
, fill_data
.data(), fill_data
.size());
3673 off
= aligned_off
+ p
->data_size();
3676 // For incremental links, fill in unused chunks in debug sections
3677 // with dummy compilation unit headers.
3678 if (this->free_space_fill_
!= NULL
)
3680 for (Free_list::Const_iterator p
= this->free_list_
.begin();
3681 p
!= this->free_list_
.end();
3684 off_t off
= p
->start_
;
3685 size_t len
= p
->end_
- off
;
3686 this->free_space_fill_
->write(of
, this->offset() + off
, len
);
3688 if (this->patch_space_
> 0)
3690 off_t off
= this->current_data_size_for_child() - this->patch_space_
;
3691 this->free_space_fill_
->write(of
, this->offset() + off
,
3692 this->patch_space_
);
3697 // If a section requires postprocessing, create the buffer to use.
3700 Output_section::create_postprocessing_buffer()
3702 gold_assert(this->requires_postprocessing());
3704 if (this->postprocessing_buffer_
!= NULL
)
3707 if (!this->input_sections_
.empty())
3709 off_t off
= this->first_input_offset_
;
3710 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3711 p
!= this->input_sections_
.end();
3714 off
= align_address(off
, p
->addralign());
3715 p
->finalize_data_size();
3716 off
+= p
->data_size();
3718 this->set_current_data_size_for_child(off
);
3721 off_t buffer_size
= this->current_data_size_for_child();
3722 this->postprocessing_buffer_
= new unsigned char[buffer_size
];
3725 // Write all the data of an Output_section into the postprocessing
3726 // buffer. This is used for sections which require postprocessing,
3727 // such as compression. Input sections are handled by
3728 // Object::Relocate.
3731 Output_section::write_to_postprocessing_buffer()
3733 gold_assert(this->requires_postprocessing());
3735 // If the target performs relaxation, we delay filler generation until now.
3736 gold_assert(!this->generate_code_fills_at_write_
|| this->fills_
.empty());
3738 unsigned char* buffer
= this->postprocessing_buffer();
3739 for (Fill_list::iterator p
= this->fills_
.begin();
3740 p
!= this->fills_
.end();
3743 std::string
fill_data(parameters
->target().code_fill(p
->length()));
3744 memcpy(buffer
+ p
->section_offset(), fill_data
.data(),
3748 off_t off
= this->first_input_offset_
;
3749 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3750 p
!= this->input_sections_
.end();
3753 off_t aligned_off
= align_address(off
, p
->addralign());
3754 if (this->generate_code_fills_at_write_
&& (off
!= aligned_off
))
3756 size_t fill_len
= aligned_off
- off
;
3757 std::string
fill_data(parameters
->target().code_fill(fill_len
));
3758 memcpy(buffer
+ off
, fill_data
.data(), fill_data
.size());
3761 p
->write_to_buffer(buffer
+ aligned_off
);
3762 off
= aligned_off
+ p
->data_size();
3766 // Get the input sections for linker script processing. We leave
3767 // behind the Output_section_data entries. Note that this may be
3768 // slightly incorrect for merge sections. We will leave them behind,
3769 // but it is possible that the script says that they should follow
3770 // some other input sections, as in:
3771 // .rodata { *(.rodata) *(.rodata.cst*) }
3772 // For that matter, we don't handle this correctly:
3773 // .rodata { foo.o(.rodata.cst*) *(.rodata.cst*) }
3774 // With luck this will never matter.
3777 Output_section::get_input_sections(
3779 const std::string
& fill
,
3780 std::list
<Input_section
>* input_sections
)
3782 if (this->checkpoint_
!= NULL
3783 && !this->checkpoint_
->input_sections_saved())
3784 this->checkpoint_
->save_input_sections();
3786 // Invalidate fast look-up maps.
3787 this->lookup_maps_
->invalidate();
3789 uint64_t orig_address
= address
;
3791 address
= align_address(address
, this->addralign());
3793 Input_section_list remaining
;
3794 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3795 p
!= this->input_sections_
.end();
3798 if (p
->is_input_section()
3799 || p
->is_relaxed_input_section()
3800 || p
->is_merge_section())
3801 input_sections
->push_back(*p
);
3804 uint64_t aligned_address
= align_address(address
, p
->addralign());
3805 if (aligned_address
!= address
&& !fill
.empty())
3807 section_size_type length
=
3808 convert_to_section_size_type(aligned_address
- address
);
3809 std::string this_fill
;
3810 this_fill
.reserve(length
);
3811 while (this_fill
.length() + fill
.length() <= length
)
3813 if (this_fill
.length() < length
)
3814 this_fill
.append(fill
, 0, length
- this_fill
.length());
3816 Output_section_data
* posd
= new Output_data_const(this_fill
, 0);
3817 remaining
.push_back(Input_section(posd
));
3819 address
= aligned_address
;
3821 remaining
.push_back(*p
);
3823 p
->finalize_data_size();
3824 address
+= p
->data_size();
3828 this->input_sections_
.swap(remaining
);
3829 this->first_input_offset_
= 0;
3831 uint64_t data_size
= address
- orig_address
;
3832 this->set_current_data_size_for_child(data_size
);
3836 // Add a script input section. SIS is an Output_section::Input_section,
3837 // which can be either a plain input section or a special input section like
3838 // a relaxed input section. For a special input section, its size must be
3842 Output_section::add_script_input_section(const Input_section
& sis
)
3844 uint64_t data_size
= sis
.data_size();
3845 uint64_t addralign
= sis
.addralign();
3846 if (addralign
> this->addralign_
)
3847 this->addralign_
= addralign
;
3849 off_t offset_in_section
= this->current_data_size_for_child();
3850 off_t aligned_offset_in_section
= align_address(offset_in_section
,
3853 this->set_current_data_size_for_child(aligned_offset_in_section
3856 this->input_sections_
.push_back(sis
);
3858 // Update fast lookup maps if necessary.
3859 if (this->lookup_maps_
->is_valid())
3861 if (sis
.is_relaxed_input_section())
3863 Output_relaxed_input_section
* poris
= sis
.relaxed_input_section();
3864 this->lookup_maps_
->add_relaxed_input_section(poris
->relobj(),
3865 poris
->shndx(), poris
);
3870 // Save states for relaxation.
3873 Output_section::save_states()
3875 gold_assert(this->checkpoint_
== NULL
);
3876 Checkpoint_output_section
* checkpoint
=
3877 new Checkpoint_output_section(this->addralign_
, this->flags_
,
3878 this->input_sections_
,
3879 this->first_input_offset_
,
3880 this->attached_input_sections_are_sorted_
);
3881 this->checkpoint_
= checkpoint
;
3882 gold_assert(this->fills_
.empty());
3886 Output_section::discard_states()
3888 gold_assert(this->checkpoint_
!= NULL
);
3889 delete this->checkpoint_
;
3890 this->checkpoint_
= NULL
;
3891 gold_assert(this->fills_
.empty());
3893 // Simply invalidate the fast lookup maps since we do not keep
3895 this->lookup_maps_
->invalidate();
3899 Output_section::restore_states()
3901 gold_assert(this->checkpoint_
!= NULL
);
3902 Checkpoint_output_section
* checkpoint
= this->checkpoint_
;
3904 this->addralign_
= checkpoint
->addralign();
3905 this->flags_
= checkpoint
->flags();
3906 this->first_input_offset_
= checkpoint
->first_input_offset();
3908 if (!checkpoint
->input_sections_saved())
3910 // If we have not copied the input sections, just resize it.
3911 size_t old_size
= checkpoint
->input_sections_size();
3912 gold_assert(this->input_sections_
.size() >= old_size
);
3913 this->input_sections_
.resize(old_size
);
3917 // We need to copy the whole list. This is not efficient for
3918 // extremely large output with hundreads of thousands of input
3919 // objects. We may need to re-think how we should pass sections
3921 this->input_sections_
= *checkpoint
->input_sections();
3924 this->attached_input_sections_are_sorted_
=
3925 checkpoint
->attached_input_sections_are_sorted();
3927 // Simply invalidate the fast lookup maps since we do not keep
3929 this->lookup_maps_
->invalidate();
3932 // Update the section offsets of input sections in this. This is required if
3933 // relaxation causes some input sections to change sizes.
3936 Output_section::adjust_section_offsets()
3938 if (!this->section_offsets_need_adjustment_
)
3942 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3943 p
!= this->input_sections_
.end();
3946 off
= align_address(off
, p
->addralign());
3947 if (p
->is_input_section())
3948 p
->relobj()->set_section_offset(p
->shndx(), off
);
3949 off
+= p
->data_size();
3952 this->section_offsets_need_adjustment_
= false;
3955 // Print to the map file.
3958 Output_section::do_print_to_mapfile(Mapfile
* mapfile
) const
3960 mapfile
->print_output_section(this);
3962 for (Input_section_list::const_iterator p
= this->input_sections_
.begin();
3963 p
!= this->input_sections_
.end();
3965 p
->print_to_mapfile(mapfile
);
3968 // Print stats for merge sections to stderr.
3971 Output_section::print_merge_stats()
3973 Input_section_list::iterator p
;
3974 for (p
= this->input_sections_
.begin();
3975 p
!= this->input_sections_
.end();
3977 p
->print_merge_stats(this->name_
);
3980 // Set a fixed layout for the section. Used for incremental update links.
3983 Output_section::set_fixed_layout(uint64_t sh_addr
, off_t sh_offset
,
3984 off_t sh_size
, uint64_t sh_addralign
)
3986 this->addralign_
= sh_addralign
;
3987 this->set_current_data_size(sh_size
);
3988 if ((this->flags_
& elfcpp::SHF_ALLOC
) != 0)
3989 this->set_address(sh_addr
);
3990 this->set_file_offset(sh_offset
);
3991 this->finalize_data_size();
3992 this->free_list_
.init(sh_size
, false);
3993 this->has_fixed_layout_
= true;
3996 // Reserve space within the fixed layout for the section. Used for
3997 // incremental update links.
4000 Output_section::reserve(uint64_t sh_offset
, uint64_t sh_size
)
4002 this->free_list_
.remove(sh_offset
, sh_offset
+ sh_size
);
4005 // Allocate space from the free list for the section. Used for
4006 // incremental update links.
4009 Output_section::allocate(off_t len
, uint64_t addralign
)
4011 return this->free_list_
.allocate(len
, addralign
, 0);
4014 // Output segment methods.
4016 Output_segment::Output_segment(elfcpp::Elf_Word type
, elfcpp::Elf_Word flags
)
4026 is_max_align_known_(false),
4027 are_addresses_set_(false),
4028 is_large_data_segment_(false),
4029 is_unique_segment_(false)
4031 // The ELF ABI specifies that a PT_TLS segment always has PF_R as
4033 if (type
== elfcpp::PT_TLS
)
4034 this->flags_
= elfcpp::PF_R
;
4037 // Add an Output_section to a PT_LOAD Output_segment.
4040 Output_segment::add_output_section_to_load(Layout
* layout
,
4042 elfcpp::Elf_Word seg_flags
)
4044 gold_assert(this->type() == elfcpp::PT_LOAD
);
4045 gold_assert((os
->flags() & elfcpp::SHF_ALLOC
) != 0);
4046 gold_assert(!this->is_max_align_known_
);
4047 gold_assert(os
->is_large_data_section() == this->is_large_data_segment());
4049 this->update_flags_for_output_section(seg_flags
);
4051 // We don't want to change the ordering if we have a linker script
4052 // with a SECTIONS clause.
4053 Output_section_order order
= os
->order();
4054 if (layout
->script_options()->saw_sections_clause())
4055 order
= static_cast<Output_section_order
>(0);
4057 gold_assert(order
!= ORDER_INVALID
);
4059 this->output_lists_
[order
].push_back(os
);
4062 // Add an Output_section to a non-PT_LOAD Output_segment.
4065 Output_segment::add_output_section_to_nonload(Output_section
* os
,
4066 elfcpp::Elf_Word seg_flags
)
4068 gold_assert(this->type() != elfcpp::PT_LOAD
);
4069 gold_assert((os
->flags() & elfcpp::SHF_ALLOC
) != 0);
4070 gold_assert(!this->is_max_align_known_
);
4072 this->update_flags_for_output_section(seg_flags
);
4074 this->output_lists_
[0].push_back(os
);
4077 // Remove an Output_section from this segment. It is an error if it
4081 Output_segment::remove_output_section(Output_section
* os
)
4083 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4085 Output_data_list
* pdl
= &this->output_lists_
[i
];
4086 for (Output_data_list::iterator p
= pdl
->begin(); p
!= pdl
->end(); ++p
)
4098 // Add an Output_data (which need not be an Output_section) to the
4099 // start of a segment.
4102 Output_segment::add_initial_output_data(Output_data
* od
)
4104 gold_assert(!this->is_max_align_known_
);
4105 Output_data_list::iterator p
= this->output_lists_
[0].begin();
4106 this->output_lists_
[0].insert(p
, od
);
4109 // Return true if this segment has any sections which hold actual
4110 // data, rather than being a BSS section.
4113 Output_segment::has_any_data_sections() const
4115 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4117 const Output_data_list
* pdl
= &this->output_lists_
[i
];
4118 for (Output_data_list::const_iterator p
= pdl
->begin();
4122 if (!(*p
)->is_section())
4124 if ((*p
)->output_section()->type() != elfcpp::SHT_NOBITS
)
4131 // Return whether the first data section (not counting TLS sections)
4132 // is a relro section.
4135 Output_segment::is_first_section_relro() const
4137 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4139 if (i
== static_cast<int>(ORDER_TLS_BSS
))
4141 const Output_data_list
* pdl
= &this->output_lists_
[i
];
4144 Output_data
* p
= pdl
->front();
4145 return p
->is_section() && p
->output_section()->is_relro();
4151 // Return the maximum alignment of the Output_data in Output_segment.
4154 Output_segment::maximum_alignment()
4156 if (!this->is_max_align_known_
)
4158 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4160 const Output_data_list
* pdl
= &this->output_lists_
[i
];
4161 uint64_t addralign
= Output_segment::maximum_alignment_list(pdl
);
4162 if (addralign
> this->max_align_
)
4163 this->max_align_
= addralign
;
4165 this->is_max_align_known_
= true;
4168 return this->max_align_
;
4171 // Return the maximum alignment of a list of Output_data.
4174 Output_segment::maximum_alignment_list(const Output_data_list
* pdl
)
4177 for (Output_data_list::const_iterator p
= pdl
->begin();
4181 uint64_t addralign
= (*p
)->addralign();
4182 if (addralign
> ret
)
4188 // Return whether this segment has any dynamic relocs.
4191 Output_segment::has_dynamic_reloc() const
4193 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4194 if (this->has_dynamic_reloc_list(&this->output_lists_
[i
]))
4199 // Return whether this Output_data_list has any dynamic relocs.
4202 Output_segment::has_dynamic_reloc_list(const Output_data_list
* pdl
) const
4204 for (Output_data_list::const_iterator p
= pdl
->begin();
4207 if ((*p
)->has_dynamic_reloc())
4212 // Set the section addresses for an Output_segment. If RESET is true,
4213 // reset the addresses first. ADDR is the address and *POFF is the
4214 // file offset. Set the section indexes starting with *PSHNDX.
4215 // INCREASE_RELRO is the size of the portion of the first non-relro
4216 // section that should be included in the PT_GNU_RELRO segment.
4217 // If this segment has relro sections, and has been aligned for
4218 // that purpose, set *HAS_RELRO to TRUE. Return the address of
4219 // the immediately following segment. Update *HAS_RELRO, *POFF,
4223 Output_segment::set_section_addresses(const Target
* target
,
4224 Layout
* layout
, bool reset
,
4226 unsigned int* increase_relro
,
4229 unsigned int* pshndx
)
4231 gold_assert(this->type_
== elfcpp::PT_LOAD
);
4233 uint64_t last_relro_pad
= 0;
4234 off_t orig_off
= *poff
;
4236 bool in_tls
= false;
4238 // If we have relro sections, we need to pad forward now so that the
4239 // relro sections plus INCREASE_RELRO end on an abi page boundary.
4240 if (parameters
->options().relro()
4241 && this->is_first_section_relro()
4242 && (!this->are_addresses_set_
|| reset
))
4244 uint64_t relro_size
= 0;
4246 uint64_t max_align
= 0;
4247 for (int i
= 0; i
<= static_cast<int>(ORDER_RELRO_LAST
); ++i
)
4249 Output_data_list
* pdl
= &this->output_lists_
[i
];
4250 Output_data_list::iterator p
;
4251 for (p
= pdl
->begin(); p
!= pdl
->end(); ++p
)
4253 if (!(*p
)->is_section())
4255 uint64_t align
= (*p
)->addralign();
4256 if (align
> max_align
)
4258 if ((*p
)->is_section_flag_set(elfcpp::SHF_TLS
))
4262 // Align the first non-TLS section to the alignment
4263 // of the TLS segment.
4267 // Ignore the size of the .tbss section.
4268 if ((*p
)->is_section_flag_set(elfcpp::SHF_TLS
)
4269 && (*p
)->is_section_type(elfcpp::SHT_NOBITS
))
4271 relro_size
= align_address(relro_size
, align
);
4272 if ((*p
)->is_address_valid())
4273 relro_size
+= (*p
)->data_size();
4276 // FIXME: This could be faster.
4277 (*p
)->set_address_and_file_offset(relro_size
,
4279 relro_size
+= (*p
)->data_size();
4280 (*p
)->reset_address_and_file_offset();
4283 if (p
!= pdl
->end())
4286 relro_size
+= *increase_relro
;
4287 // Pad the total relro size to a multiple of the maximum
4288 // section alignment seen.
4289 uint64_t aligned_size
= align_address(relro_size
, max_align
);
4290 // Note the amount of padding added after the last relro section.
4291 last_relro_pad
= aligned_size
- relro_size
;
4294 uint64_t page_align
= parameters
->target().abi_pagesize();
4296 // Align to offset N such that (N + RELRO_SIZE) % PAGE_ALIGN == 0.
4297 uint64_t desired_align
= page_align
- (aligned_size
% page_align
);
4298 if (desired_align
< off
% page_align
)
4300 off
+= desired_align
- off
% page_align
;
4301 addr
+= off
- orig_off
;
4306 if (!reset
&& this->are_addresses_set_
)
4308 gold_assert(this->paddr_
== addr
);
4309 addr
= this->vaddr_
;
4313 this->vaddr_
= addr
;
4314 this->paddr_
= addr
;
4315 this->are_addresses_set_
= true;
4320 this->offset_
= orig_off
;
4324 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4326 if (i
== static_cast<int>(ORDER_RELRO_LAST
))
4328 *poff
+= last_relro_pad
;
4329 addr
+= last_relro_pad
;
4330 if (this->output_lists_
[i
].empty())
4332 // If there is nothing in the ORDER_RELRO_LAST list,
4333 // the padding will occur at the end of the relro
4334 // segment, and we need to add it to *INCREASE_RELRO.
4335 *increase_relro
+= last_relro_pad
;
4338 addr
= this->set_section_list_addresses(layout
, reset
,
4339 &this->output_lists_
[i
],
4340 addr
, poff
, pshndx
, &in_tls
);
4341 if (i
< static_cast<int>(ORDER_SMALL_BSS
))
4343 this->filesz_
= *poff
- orig_off
;
4350 // If the last section was a TLS section, align upward to the
4351 // alignment of the TLS segment, so that the overall size of the TLS
4352 // segment is aligned.
4355 uint64_t segment_align
= layout
->tls_segment()->maximum_alignment();
4356 *poff
= align_address(*poff
, segment_align
);
4359 this->memsz_
= *poff
- orig_off
;
4361 // Ignore the file offset adjustments made by the BSS Output_data
4365 // If code segments must contain only code, and this code segment is
4366 // page-aligned in the file, then fill it out to a whole page with
4367 // code fill (the tail of the segment will not be within any section).
4368 // Thus the entire code segment can be mapped from the file as whole
4369 // pages and that mapping will contain only valid instructions.
4370 if (target
->isolate_execinstr() && (this->flags() & elfcpp::PF_X
) != 0)
4372 uint64_t abi_pagesize
= target
->abi_pagesize();
4373 if (orig_off
% abi_pagesize
== 0 && off
% abi_pagesize
!= 0)
4375 size_t fill_size
= abi_pagesize
- (off
% abi_pagesize
);
4377 std::string fill_data
;
4378 if (target
->has_code_fill())
4379 fill_data
= target
->code_fill(fill_size
);
4381 fill_data
.resize(fill_size
); // Zero fill.
4383 Output_data_const
* fill
= new Output_data_const(fill_data
, 0);
4384 fill
->set_address(this->vaddr_
+ this->memsz_
);
4385 fill
->set_file_offset(off
);
4386 layout
->add_relax_output(fill
);
4389 gold_assert(off
% abi_pagesize
== 0);
4391 gold_assert(ret
% abi_pagesize
== 0);
4393 gold_assert((uint64_t) this->filesz_
== this->memsz_
);
4394 this->memsz_
= this->filesz_
+= fill_size
;
4403 // Set the addresses and file offsets in a list of Output_data
4407 Output_segment::set_section_list_addresses(Layout
* layout
, bool reset
,
4408 Output_data_list
* pdl
,
4409 uint64_t addr
, off_t
* poff
,
4410 unsigned int* pshndx
,
4413 off_t startoff
= *poff
;
4414 // For incremental updates, we may allocate non-fixed sections from
4415 // free space in the file. This keeps track of the high-water mark.
4416 off_t maxoff
= startoff
;
4418 off_t off
= startoff
;
4419 for (Output_data_list::iterator p
= pdl
->begin();
4424 (*p
)->reset_address_and_file_offset();
4426 // When doing an incremental update or when using a linker script,
4427 // the section will most likely already have an address.
4428 if (!(*p
)->is_address_valid())
4430 uint64_t align
= (*p
)->addralign();
4432 if ((*p
)->is_section_flag_set(elfcpp::SHF_TLS
))
4434 // Give the first TLS section the alignment of the
4435 // entire TLS segment. Otherwise the TLS segment as a
4436 // whole may be misaligned.
4439 Output_segment
* tls_segment
= layout
->tls_segment();
4440 gold_assert(tls_segment
!= NULL
);
4441 uint64_t segment_align
= tls_segment
->maximum_alignment();
4442 gold_assert(segment_align
>= align
);
4443 align
= segment_align
;
4450 // If this is the first section after the TLS segment,
4451 // align it to at least the alignment of the TLS
4452 // segment, so that the size of the overall TLS segment
4456 uint64_t segment_align
=
4457 layout
->tls_segment()->maximum_alignment();
4458 if (segment_align
> align
)
4459 align
= segment_align
;
4465 if (!parameters
->incremental_update())
4467 off
= align_address(off
, align
);
4468 (*p
)->set_address_and_file_offset(addr
+ (off
- startoff
), off
);
4472 // Incremental update: allocate file space from free list.
4473 (*p
)->pre_finalize_data_size();
4474 off_t current_size
= (*p
)->current_data_size();
4475 off
= layout
->allocate(current_size
, align
, startoff
);
4478 gold_assert((*p
)->output_section() != NULL
);
4479 gold_fallback(_("out of patch space for section %s; "
4480 "relink with --incremental-full"),
4481 (*p
)->output_section()->name());
4483 (*p
)->set_address_and_file_offset(addr
+ (off
- startoff
), off
);
4484 if ((*p
)->data_size() > current_size
)
4486 gold_assert((*p
)->output_section() != NULL
);
4487 gold_fallback(_("%s: section changed size; "
4488 "relink with --incremental-full"),
4489 (*p
)->output_section()->name());
4493 else if (parameters
->incremental_update())
4495 // For incremental updates, use the fixed offset for the
4496 // high-water mark computation.
4497 off
= (*p
)->offset();
4501 // The script may have inserted a skip forward, but it
4502 // better not have moved backward.
4503 if ((*p
)->address() >= addr
+ (off
- startoff
))
4504 off
+= (*p
)->address() - (addr
+ (off
- startoff
));
4507 if (!layout
->script_options()->saw_sections_clause())
4511 Output_section
* os
= (*p
)->output_section();
4513 // Cast to unsigned long long to avoid format warnings.
4514 unsigned long long previous_dot
=
4515 static_cast<unsigned long long>(addr
+ (off
- startoff
));
4516 unsigned long long dot
=
4517 static_cast<unsigned long long>((*p
)->address());
4520 gold_error(_("dot moves backward in linker script "
4521 "from 0x%llx to 0x%llx"), previous_dot
, dot
);
4523 gold_error(_("address of section '%s' moves backward "
4524 "from 0x%llx to 0x%llx"),
4525 os
->name(), previous_dot
, dot
);
4528 (*p
)->set_file_offset(off
);
4529 (*p
)->finalize_data_size();
4532 if (parameters
->incremental_update())
4533 gold_debug(DEBUG_INCREMENTAL
,
4534 "set_section_list_addresses: %08lx %08lx %s",
4535 static_cast<long>(off
),
4536 static_cast<long>((*p
)->data_size()),
4537 ((*p
)->output_section() != NULL
4538 ? (*p
)->output_section()->name() : "(special)"));
4540 // We want to ignore the size of a SHF_TLS SHT_NOBITS
4541 // section. Such a section does not affect the size of a
4543 if (!(*p
)->is_section_flag_set(elfcpp::SHF_TLS
)
4544 || !(*p
)->is_section_type(elfcpp::SHT_NOBITS
))
4545 off
+= (*p
)->data_size();
4550 if ((*p
)->is_section())
4552 (*p
)->set_out_shndx(*pshndx
);
4558 return addr
+ (maxoff
- startoff
);
4561 // For a non-PT_LOAD segment, set the offset from the sections, if
4562 // any. Add INCREASE to the file size and the memory size.
4565 Output_segment::set_offset(unsigned int increase
)
4567 gold_assert(this->type_
!= elfcpp::PT_LOAD
);
4569 gold_assert(!this->are_addresses_set_
);
4571 // A non-load section only uses output_lists_[0].
4573 Output_data_list
* pdl
= &this->output_lists_
[0];
4577 gold_assert(increase
== 0);
4580 this->are_addresses_set_
= true;
4582 this->min_p_align_
= 0;
4588 // Find the first and last section by address.
4589 const Output_data
* first
= NULL
;
4590 const Output_data
* last_data
= NULL
;
4591 const Output_data
* last_bss
= NULL
;
4592 for (Output_data_list::const_iterator p
= pdl
->begin();
4597 || (*p
)->address() < first
->address()
4598 || ((*p
)->address() == first
->address()
4599 && (*p
)->data_size() < first
->data_size()))
4601 const Output_data
** plast
;
4602 if ((*p
)->is_section()
4603 && (*p
)->output_section()->type() == elfcpp::SHT_NOBITS
)
4608 || (*p
)->address() > (*plast
)->address()
4609 || ((*p
)->address() == (*plast
)->address()
4610 && (*p
)->data_size() > (*plast
)->data_size()))
4614 this->vaddr_
= first
->address();
4615 this->paddr_
= (first
->has_load_address()
4616 ? first
->load_address()
4618 this->are_addresses_set_
= true;
4619 this->offset_
= first
->offset();
4621 if (last_data
== NULL
)
4624 this->filesz_
= (last_data
->address()
4625 + last_data
->data_size()
4628 const Output_data
* last
= last_bss
!= NULL
? last_bss
: last_data
;
4629 this->memsz_
= (last
->address()
4633 this->filesz_
+= increase
;
4634 this->memsz_
+= increase
;
4636 // If this is a RELRO segment, verify that the segment ends at a
4638 if (this->type_
== elfcpp::PT_GNU_RELRO
)
4640 uint64_t page_align
= parameters
->target().abi_pagesize();
4641 uint64_t segment_end
= this->vaddr_
+ this->memsz_
;
4642 if (parameters
->incremental_update())
4644 // The INCREASE_RELRO calculation is bypassed for an incremental
4645 // update, so we need to adjust the segment size manually here.
4646 segment_end
= align_address(segment_end
, page_align
);
4647 this->memsz_
= segment_end
- this->vaddr_
;
4650 gold_assert(segment_end
== align_address(segment_end
, page_align
));
4653 // If this is a TLS segment, align the memory size. The code in
4654 // set_section_list ensures that the section after the TLS segment
4655 // is aligned to give us room.
4656 if (this->type_
== elfcpp::PT_TLS
)
4658 uint64_t segment_align
= this->maximum_alignment();
4659 gold_assert(this->vaddr_
== align_address(this->vaddr_
, segment_align
));
4660 this->memsz_
= align_address(this->memsz_
, segment_align
);
4664 // Set the TLS offsets of the sections in the PT_TLS segment.
4667 Output_segment::set_tls_offsets()
4669 gold_assert(this->type_
== elfcpp::PT_TLS
);
4671 for (Output_data_list::iterator p
= this->output_lists_
[0].begin();
4672 p
!= this->output_lists_
[0].end();
4674 (*p
)->set_tls_offset(this->vaddr_
);
4677 // Return the first section.
4680 Output_segment::first_section() const
4682 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4684 const Output_data_list
* pdl
= &this->output_lists_
[i
];
4685 for (Output_data_list::const_iterator p
= pdl
->begin();
4689 if ((*p
)->is_section())
4690 return (*p
)->output_section();
4696 // Return the number of Output_sections in an Output_segment.
4699 Output_segment::output_section_count() const
4701 unsigned int ret
= 0;
4702 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4703 ret
+= this->output_section_count_list(&this->output_lists_
[i
]);
4707 // Return the number of Output_sections in an Output_data_list.
4710 Output_segment::output_section_count_list(const Output_data_list
* pdl
) const
4712 unsigned int count
= 0;
4713 for (Output_data_list::const_iterator p
= pdl
->begin();
4717 if ((*p
)->is_section())
4723 // Return the section attached to the list segment with the lowest
4724 // load address. This is used when handling a PHDRS clause in a
4728 Output_segment::section_with_lowest_load_address() const
4730 Output_section
* found
= NULL
;
4731 uint64_t found_lma
= 0;
4732 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4733 this->lowest_load_address_in_list(&this->output_lists_
[i
], &found
,
4738 // Look through a list for a section with a lower load address.
4741 Output_segment::lowest_load_address_in_list(const Output_data_list
* pdl
,
4742 Output_section
** found
,
4743 uint64_t* found_lma
) const
4745 for (Output_data_list::const_iterator p
= pdl
->begin();
4749 if (!(*p
)->is_section())
4751 Output_section
* os
= static_cast<Output_section
*>(*p
);
4752 uint64_t lma
= (os
->has_load_address()
4753 ? os
->load_address()
4755 if (*found
== NULL
|| lma
< *found_lma
)
4763 // Write the segment data into *OPHDR.
4765 template<int size
, bool big_endian
>
4767 Output_segment::write_header(elfcpp::Phdr_write
<size
, big_endian
>* ophdr
)
4769 ophdr
->put_p_type(this->type_
);
4770 ophdr
->put_p_offset(this->offset_
);
4771 ophdr
->put_p_vaddr(this->vaddr_
);
4772 ophdr
->put_p_paddr(this->paddr_
);
4773 ophdr
->put_p_filesz(this->filesz_
);
4774 ophdr
->put_p_memsz(this->memsz_
);
4775 ophdr
->put_p_flags(this->flags_
);
4776 ophdr
->put_p_align(std::max(this->min_p_align_
, this->maximum_alignment()));
4779 // Write the section headers into V.
4781 template<int size
, bool big_endian
>
4783 Output_segment::write_section_headers(const Layout
* layout
,
4784 const Stringpool
* secnamepool
,
4786 unsigned int* pshndx
) const
4788 // Every section that is attached to a segment must be attached to a
4789 // PT_LOAD segment, so we only write out section headers for PT_LOAD
4791 if (this->type_
!= elfcpp::PT_LOAD
)
4794 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4796 const Output_data_list
* pdl
= &this->output_lists_
[i
];
4797 v
= this->write_section_headers_list
<size
, big_endian
>(layout
,
4806 template<int size
, bool big_endian
>
4808 Output_segment::write_section_headers_list(const Layout
* layout
,
4809 const Stringpool
* secnamepool
,
4810 const Output_data_list
* pdl
,
4812 unsigned int* pshndx
) const
4814 const int shdr_size
= elfcpp::Elf_sizes
<size
>::shdr_size
;
4815 for (Output_data_list::const_iterator p
= pdl
->begin();
4819 if ((*p
)->is_section())
4821 const Output_section
* ps
= static_cast<const Output_section
*>(*p
);
4822 gold_assert(*pshndx
== ps
->out_shndx());
4823 elfcpp::Shdr_write
<size
, big_endian
> oshdr(v
);
4824 ps
->write_header(layout
, secnamepool
, &oshdr
);
4832 // Print the output sections to the map file.
4835 Output_segment::print_sections_to_mapfile(Mapfile
* mapfile
) const
4837 if (this->type() != elfcpp::PT_LOAD
)
4839 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4840 this->print_section_list_to_mapfile(mapfile
, &this->output_lists_
[i
]);
4843 // Print an output section list to the map file.
4846 Output_segment::print_section_list_to_mapfile(Mapfile
* mapfile
,
4847 const Output_data_list
* pdl
) const
4849 for (Output_data_list::const_iterator p
= pdl
->begin();
4852 (*p
)->print_to_mapfile(mapfile
);
4855 // Output_file methods.
4857 Output_file::Output_file(const char* name
)
4862 map_is_anonymous_(false),
4863 map_is_allocated_(false),
4864 is_temporary_(false)
4868 // Try to open an existing file. Returns false if the file doesn't
4869 // exist, has a size of 0 or can't be mmapped. If BASE_NAME is not
4870 // NULL, open that file as the base for incremental linking, and
4871 // copy its contents to the new output file. This routine can
4872 // be called for incremental updates, in which case WRITABLE should
4873 // be true, or by the incremental-dump utility, in which case
4874 // WRITABLE should be false.
4877 Output_file::open_base_file(const char* base_name
, bool writable
)
4879 // The name "-" means "stdout".
4880 if (strcmp(this->name_
, "-") == 0)
4883 bool use_base_file
= base_name
!= NULL
;
4885 base_name
= this->name_
;
4886 else if (strcmp(base_name
, this->name_
) == 0)
4887 gold_fatal(_("%s: incremental base and output file name are the same"),
4890 // Don't bother opening files with a size of zero.
4892 if (::stat(base_name
, &s
) != 0)
4894 gold_info(_("%s: stat: %s"), base_name
, strerror(errno
));
4899 gold_info(_("%s: incremental base file is empty"), base_name
);
4903 // If we're using a base file, we want to open it read-only.
4907 int oflags
= writable
? O_RDWR
: O_RDONLY
;
4908 int o
= open_descriptor(-1, base_name
, oflags
, 0);
4911 gold_info(_("%s: open: %s"), base_name
, strerror(errno
));
4915 // If the base file and the output file are different, open a
4916 // new output file and read the contents from the base file into
4917 // the newly-mapped region.
4920 this->open(s
.st_size
);
4921 ssize_t bytes_to_read
= s
.st_size
;
4922 unsigned char* p
= this->base_
;
4923 while (bytes_to_read
> 0)
4925 ssize_t len
= ::read(o
, p
, bytes_to_read
);
4928 gold_info(_("%s: read failed: %s"), base_name
, strerror(errno
));
4933 gold_info(_("%s: file too short: read only %lld of %lld bytes"),
4935 static_cast<long long>(s
.st_size
- bytes_to_read
),
4936 static_cast<long long>(s
.st_size
));
4940 bytes_to_read
-= len
;
4947 this->file_size_
= s
.st_size
;
4949 if (!this->map_no_anonymous(writable
))
4951 release_descriptor(o
, true);
4953 this->file_size_
= 0;
4960 // Open the output file.
4963 Output_file::open(off_t file_size
)
4965 this->file_size_
= file_size
;
4967 // Unlink the file first; otherwise the open() may fail if the file
4968 // is busy (e.g. it's an executable that's currently being executed).
4970 // However, the linker may be part of a system where a zero-length
4971 // file is created for it to write to, with tight permissions (gcc
4972 // 2.95 did something like this). Unlinking the file would work
4973 // around those permission controls, so we only unlink if the file
4974 // has a non-zero size. We also unlink only regular files to avoid
4975 // trouble with directories/etc.
4977 // If we fail, continue; this command is merely a best-effort attempt
4978 // to improve the odds for open().
4980 // We let the name "-" mean "stdout"
4981 if (!this->is_temporary_
)
4983 if (strcmp(this->name_
, "-") == 0)
4984 this->o_
= STDOUT_FILENO
;
4988 if (::stat(this->name_
, &s
) == 0
4989 && (S_ISREG (s
.st_mode
) || S_ISLNK (s
.st_mode
)))
4992 ::unlink(this->name_
);
4993 else if (!parameters
->options().relocatable())
4995 // If we don't unlink the existing file, add execute
4996 // permission where read permissions already exist
4997 // and where the umask permits.
4998 int mask
= ::umask(0);
5000 s
.st_mode
|= (s
.st_mode
& 0444) >> 2;
5001 ::chmod(this->name_
, s
.st_mode
& ~mask
);
5005 int mode
= parameters
->options().relocatable() ? 0666 : 0777;
5006 int o
= open_descriptor(-1, this->name_
, O_RDWR
| O_CREAT
| O_TRUNC
,
5009 gold_fatal(_("%s: open: %s"), this->name_
, strerror(errno
));
5017 // Resize the output file.
5020 Output_file::resize(off_t file_size
)
5022 // If the mmap is mapping an anonymous memory buffer, this is easy:
5023 // just mremap to the new size. If it's mapping to a file, we want
5024 // to unmap to flush to the file, then remap after growing the file.
5025 if (this->map_is_anonymous_
)
5028 if (!this->map_is_allocated_
)
5030 base
= ::mremap(this->base_
, this->file_size_
, file_size
,
5032 if (base
== MAP_FAILED
)
5033 gold_fatal(_("%s: mremap: %s"), this->name_
, strerror(errno
));
5037 base
= realloc(this->base_
, file_size
);
5040 if (file_size
> this->file_size_
)
5041 memset(static_cast<char*>(base
) + this->file_size_
, 0,
5042 file_size
- this->file_size_
);
5044 this->base_
= static_cast<unsigned char*>(base
);
5045 this->file_size_
= file_size
;
5050 this->file_size_
= file_size
;
5051 if (!this->map_no_anonymous(true))
5052 gold_fatal(_("%s: mmap: %s"), this->name_
, strerror(errno
));
5056 // Map an anonymous block of memory which will later be written to the
5057 // file. Return whether the map succeeded.
5060 Output_file::map_anonymous()
5062 void* base
= ::mmap(NULL
, this->file_size_
, PROT_READ
| PROT_WRITE
,
5063 MAP_PRIVATE
| MAP_ANONYMOUS
, -1, 0);
5064 if (base
== MAP_FAILED
)
5066 base
= malloc(this->file_size_
);
5069 memset(base
, 0, this->file_size_
);
5070 this->map_is_allocated_
= true;
5072 this->base_
= static_cast<unsigned char*>(base
);
5073 this->map_is_anonymous_
= true;
5077 // Map the file into memory. Return whether the mapping succeeded.
5078 // If WRITABLE is true, map with write access.
5081 Output_file::map_no_anonymous(bool writable
)
5083 const int o
= this->o_
;
5085 // If the output file is not a regular file, don't try to mmap it;
5086 // instead, we'll mmap a block of memory (an anonymous buffer), and
5087 // then later write the buffer to the file.
5089 struct stat statbuf
;
5090 if (o
== STDOUT_FILENO
|| o
== STDERR_FILENO
5091 || ::fstat(o
, &statbuf
) != 0
5092 || !S_ISREG(statbuf
.st_mode
)
5093 || this->is_temporary_
)
5096 // Ensure that we have disk space available for the file. If we
5097 // don't do this, it is possible that we will call munmap, close,
5098 // and exit with dirty buffers still in the cache with no assigned
5099 // disk blocks. If the disk is out of space at that point, the
5100 // output file will wind up incomplete, but we will have already
5101 // exited. The alternative to fallocate would be to use fdatasync,
5102 // but that would be a more significant performance hit.
5105 int err
= gold_fallocate(o
, 0, this->file_size_
);
5107 gold_fatal(_("%s: %s"), this->name_
, strerror(err
));
5110 // Map the file into memory.
5111 int prot
= PROT_READ
;
5114 base
= ::mmap(NULL
, this->file_size_
, prot
, MAP_SHARED
, o
, 0);
5116 // The mmap call might fail because of file system issues: the file
5117 // system might not support mmap at all, or it might not support
5118 // mmap with PROT_WRITE.
5119 if (base
== MAP_FAILED
)
5122 this->map_is_anonymous_
= false;
5123 this->base_
= static_cast<unsigned char*>(base
);
5127 // Map the file into memory.
5132 if (parameters
->options().mmap_output_file()
5133 && this->map_no_anonymous(true))
5136 // The mmap call might fail because of file system issues: the file
5137 // system might not support mmap at all, or it might not support
5138 // mmap with PROT_WRITE. I'm not sure which errno values we will
5139 // see in all cases, so if the mmap fails for any reason and we
5140 // don't care about file contents, try for an anonymous map.
5141 if (this->map_anonymous())
5144 gold_fatal(_("%s: mmap: failed to allocate %lu bytes for output file: %s"),
5145 this->name_
, static_cast<unsigned long>(this->file_size_
),
5149 // Unmap the file from memory.
5152 Output_file::unmap()
5154 if (this->map_is_anonymous_
)
5156 // We've already written out the data, so there is no reason to
5157 // waste time unmapping or freeing the memory.
5161 if (::munmap(this->base_
, this->file_size_
) < 0)
5162 gold_error(_("%s: munmap: %s"), this->name_
, strerror(errno
));
5167 // Close the output file.
5170 Output_file::close()
5172 // If the map isn't file-backed, we need to write it now.
5173 if (this->map_is_anonymous_
&& !this->is_temporary_
)
5175 size_t bytes_to_write
= this->file_size_
;
5177 while (bytes_to_write
> 0)
5179 ssize_t bytes_written
= ::write(this->o_
, this->base_
+ offset
,
5181 if (bytes_written
== 0)
5182 gold_error(_("%s: write: unexpected 0 return-value"), this->name_
);
5183 else if (bytes_written
< 0)
5184 gold_error(_("%s: write: %s"), this->name_
, strerror(errno
));
5187 bytes_to_write
-= bytes_written
;
5188 offset
+= bytes_written
;
5194 // We don't close stdout or stderr
5195 if (this->o_
!= STDOUT_FILENO
5196 && this->o_
!= STDERR_FILENO
5197 && !this->is_temporary_
)
5198 if (::close(this->o_
) < 0)
5199 gold_error(_("%s: close: %s"), this->name_
, strerror(errno
));
5203 // Instantiate the templates we need. We could use the configure
5204 // script to restrict this to only the ones for implemented targets.
5206 #ifdef HAVE_TARGET_32_LITTLE
5209 Output_section::add_input_section
<32, false>(
5211 Sized_relobj_file
<32, false>* object
,
5213 const char* secname
,
5214 const elfcpp::Shdr
<32, false>& shdr
,
5215 unsigned int reloc_shndx
,
5216 bool have_sections_script
);
5219 #ifdef HAVE_TARGET_32_BIG
5222 Output_section::add_input_section
<32, true>(
5224 Sized_relobj_file
<32, true>* object
,
5226 const char* secname
,
5227 const elfcpp::Shdr
<32, true>& shdr
,
5228 unsigned int reloc_shndx
,
5229 bool have_sections_script
);
5232 #ifdef HAVE_TARGET_64_LITTLE
5235 Output_section::add_input_section
<64, false>(
5237 Sized_relobj_file
<64, false>* object
,
5239 const char* secname
,
5240 const elfcpp::Shdr
<64, false>& shdr
,
5241 unsigned int reloc_shndx
,
5242 bool have_sections_script
);
5245 #ifdef HAVE_TARGET_64_BIG
5248 Output_section::add_input_section
<64, true>(
5250 Sized_relobj_file
<64, true>* object
,
5252 const char* secname
,
5253 const elfcpp::Shdr
<64, true>& shdr
,
5254 unsigned int reloc_shndx
,
5255 bool have_sections_script
);
5258 #ifdef HAVE_TARGET_32_LITTLE
5260 class Output_reloc
<elfcpp::SHT_REL
, false, 32, false>;
5263 #ifdef HAVE_TARGET_32_BIG
5265 class Output_reloc
<elfcpp::SHT_REL
, false, 32, true>;
5268 #ifdef HAVE_TARGET_64_LITTLE
5270 class Output_reloc
<elfcpp::SHT_REL
, false, 64, false>;
5273 #ifdef HAVE_TARGET_64_BIG
5275 class Output_reloc
<elfcpp::SHT_REL
, false, 64, true>;
5278 #ifdef HAVE_TARGET_32_LITTLE
5280 class Output_reloc
<elfcpp::SHT_REL
, true, 32, false>;
5283 #ifdef HAVE_TARGET_32_BIG
5285 class Output_reloc
<elfcpp::SHT_REL
, true, 32, true>;
5288 #ifdef HAVE_TARGET_64_LITTLE
5290 class Output_reloc
<elfcpp::SHT_REL
, true, 64, false>;
5293 #ifdef HAVE_TARGET_64_BIG
5295 class Output_reloc
<elfcpp::SHT_REL
, true, 64, true>;
5298 #ifdef HAVE_TARGET_32_LITTLE
5300 class Output_reloc
<elfcpp::SHT_RELA
, false, 32, false>;
5303 #ifdef HAVE_TARGET_32_BIG
5305 class Output_reloc
<elfcpp::SHT_RELA
, false, 32, true>;
5308 #ifdef HAVE_TARGET_64_LITTLE
5310 class Output_reloc
<elfcpp::SHT_RELA
, false, 64, false>;
5313 #ifdef HAVE_TARGET_64_BIG
5315 class Output_reloc
<elfcpp::SHT_RELA
, false, 64, true>;
5318 #ifdef HAVE_TARGET_32_LITTLE
5320 class Output_reloc
<elfcpp::SHT_RELA
, true, 32, false>;
5323 #ifdef HAVE_TARGET_32_BIG
5325 class Output_reloc
<elfcpp::SHT_RELA
, true, 32, true>;
5328 #ifdef HAVE_TARGET_64_LITTLE
5330 class Output_reloc
<elfcpp::SHT_RELA
, true, 64, false>;
5333 #ifdef HAVE_TARGET_64_BIG
5335 class Output_reloc
<elfcpp::SHT_RELA
, true, 64, true>;
5338 #ifdef HAVE_TARGET_32_LITTLE
5340 class Output_data_reloc
<elfcpp::SHT_REL
, false, 32, false>;
5343 #ifdef HAVE_TARGET_32_BIG
5345 class Output_data_reloc
<elfcpp::SHT_REL
, false, 32, true>;
5348 #ifdef HAVE_TARGET_64_LITTLE
5350 class Output_data_reloc
<elfcpp::SHT_REL
, false, 64, false>;
5353 #ifdef HAVE_TARGET_64_BIG
5355 class Output_data_reloc
<elfcpp::SHT_REL
, false, 64, true>;
5358 #ifdef HAVE_TARGET_32_LITTLE
5360 class Output_data_reloc
<elfcpp::SHT_REL
, true, 32, false>;
5363 #ifdef HAVE_TARGET_32_BIG
5365 class Output_data_reloc
<elfcpp::SHT_REL
, true, 32, true>;
5368 #ifdef HAVE_TARGET_64_LITTLE
5370 class Output_data_reloc
<elfcpp::SHT_REL
, true, 64, false>;
5373 #ifdef HAVE_TARGET_64_BIG
5375 class Output_data_reloc
<elfcpp::SHT_REL
, true, 64, true>;
5378 #ifdef HAVE_TARGET_32_LITTLE
5380 class Output_data_reloc
<elfcpp::SHT_RELA
, false, 32, false>;
5383 #ifdef HAVE_TARGET_32_BIG
5385 class Output_data_reloc
<elfcpp::SHT_RELA
, false, 32, true>;
5388 #ifdef HAVE_TARGET_64_LITTLE
5390 class Output_data_reloc
<elfcpp::SHT_RELA
, false, 64, false>;
5393 #ifdef HAVE_TARGET_64_BIG
5395 class Output_data_reloc
<elfcpp::SHT_RELA
, false, 64, true>;
5398 #ifdef HAVE_TARGET_32_LITTLE
5400 class Output_data_reloc
<elfcpp::SHT_RELA
, true, 32, false>;
5403 #ifdef HAVE_TARGET_32_BIG
5405 class Output_data_reloc
<elfcpp::SHT_RELA
, true, 32, true>;
5408 #ifdef HAVE_TARGET_64_LITTLE
5410 class Output_data_reloc
<elfcpp::SHT_RELA
, true, 64, false>;
5413 #ifdef HAVE_TARGET_64_BIG
5415 class Output_data_reloc
<elfcpp::SHT_RELA
, true, 64, true>;
5418 #ifdef HAVE_TARGET_32_LITTLE
5420 class Output_relocatable_relocs
<elfcpp::SHT_REL
, 32, false>;
5423 #ifdef HAVE_TARGET_32_BIG
5425 class Output_relocatable_relocs
<elfcpp::SHT_REL
, 32, true>;
5428 #ifdef HAVE_TARGET_64_LITTLE
5430 class Output_relocatable_relocs
<elfcpp::SHT_REL
, 64, false>;
5433 #ifdef HAVE_TARGET_64_BIG
5435 class Output_relocatable_relocs
<elfcpp::SHT_REL
, 64, true>;
5438 #ifdef HAVE_TARGET_32_LITTLE
5440 class Output_relocatable_relocs
<elfcpp::SHT_RELA
, 32, false>;
5443 #ifdef HAVE_TARGET_32_BIG
5445 class Output_relocatable_relocs
<elfcpp::SHT_RELA
, 32, true>;
5448 #ifdef HAVE_TARGET_64_LITTLE
5450 class Output_relocatable_relocs
<elfcpp::SHT_RELA
, 64, false>;
5453 #ifdef HAVE_TARGET_64_BIG
5455 class Output_relocatable_relocs
<elfcpp::SHT_RELA
, 64, true>;
5458 #ifdef HAVE_TARGET_32_LITTLE
5460 class Output_data_group
<32, false>;
5463 #ifdef HAVE_TARGET_32_BIG
5465 class Output_data_group
<32, true>;
5468 #ifdef HAVE_TARGET_64_LITTLE
5470 class Output_data_group
<64, false>;
5473 #ifdef HAVE_TARGET_64_BIG
5475 class Output_data_group
<64, true>;
5479 class Output_data_got
<32, false>;
5482 class Output_data_got
<32, true>;
5485 class Output_data_got
<64, false>;
5488 class Output_data_got
<64, true>;
5490 } // End namespace gold.