1 // output.cc -- manage the output file for gold
3 // Copyright 2006, 2007, 2008, 2009, 2010, 2011, 2012
4 // Free Software Foundation, Inc.
5 // Written by Ian Lance Taylor <iant@google.com>.
7 // This file is part of gold.
9 // This program is free software; you can redistribute it and/or modify
10 // it under the terms of the GNU General Public License as published by
11 // the Free Software Foundation; either version 3 of the License, or
12 // (at your option) any later version.
14 // This program is distributed in the hope that it will be useful,
15 // but WITHOUT ANY WARRANTY; without even the implied warranty of
16 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 // GNU General Public License for more details.
19 // You should have received a copy of the GNU General Public License
20 // along with this program; if not, write to the Free Software
21 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
22 // MA 02110-1301, USA.
34 #ifdef HAVE_SYS_MMAN_H
38 #include "libiberty.h"
41 #include "parameters.h"
46 #include "descriptors.h"
50 // For systems without mmap support.
52 # define mmap gold_mmap
53 # define munmap gold_munmap
54 # define mremap gold_mremap
56 # define MAP_FAILED (reinterpret_cast<void*>(-1))
65 # define MAP_PRIVATE 0
67 # ifndef MAP_ANONYMOUS
68 # define MAP_ANONYMOUS 0
75 # define ENOSYS EINVAL
79 gold_mmap(void *, size_t, int, int, int, off_t
)
86 gold_munmap(void *, size_t)
93 gold_mremap(void *, size_t, size_t, int)
101 #if defined(HAVE_MMAP) && !defined(HAVE_MREMAP)
102 # define mremap gold_mremap
103 extern "C" void *gold_mremap(void *, size_t, size_t, int);
106 // Some BSD systems still use MAP_ANON instead of MAP_ANONYMOUS
107 #ifndef MAP_ANONYMOUS
108 # define MAP_ANONYMOUS MAP_ANON
111 #ifndef MREMAP_MAYMOVE
112 # define MREMAP_MAYMOVE 1
115 // Mingw does not have S_ISLNK.
117 # define S_ISLNK(mode) 0
123 // A wrapper around posix_fallocate. If we don't have posix_fallocate,
124 // or the --no-posix-fallocate option is set, we try the fallocate
125 // system call directly. If that fails, we use ftruncate to set
126 // the file size and hope that there is enough disk space.
129 gold_fallocate(int o
, off_t offset
, off_t len
)
131 #ifdef HAVE_POSIX_FALLOCATE
132 if (parameters
->options().posix_fallocate())
133 return ::posix_fallocate(o
, offset
, len
);
134 #endif // defined(HAVE_POSIX_FALLOCATE)
135 #ifdef HAVE_FALLOCATE
136 if (::fallocate(o
, 0, offset
, len
) == 0)
138 #endif // defined(HAVE_FALLOCATE)
139 if (::ftruncate(o
, offset
+ len
) < 0)
144 // Output_data variables.
146 bool Output_data::allocated_sizes_are_fixed
;
148 // Output_data methods.
150 Output_data::~Output_data()
154 // Return the default alignment for the target size.
157 Output_data::default_alignment()
159 return Output_data::default_alignment_for_size(
160 parameters
->target().get_size());
163 // Return the default alignment for a size--32 or 64.
166 Output_data::default_alignment_for_size(int size
)
176 // Output_section_header methods. This currently assumes that the
177 // segment and section lists are complete at construction time.
179 Output_section_headers::Output_section_headers(
180 const Layout
* layout
,
181 const Layout::Segment_list
* segment_list
,
182 const Layout::Section_list
* section_list
,
183 const Layout::Section_list
* unattached_section_list
,
184 const Stringpool
* secnamepool
,
185 const Output_section
* shstrtab_section
)
187 segment_list_(segment_list
),
188 section_list_(section_list
),
189 unattached_section_list_(unattached_section_list
),
190 secnamepool_(secnamepool
),
191 shstrtab_section_(shstrtab_section
)
195 // Compute the current data size.
198 Output_section_headers::do_size() const
200 // Count all the sections. Start with 1 for the null section.
202 if (!parameters
->options().relocatable())
204 for (Layout::Segment_list::const_iterator p
=
205 this->segment_list_
->begin();
206 p
!= this->segment_list_
->end();
208 if ((*p
)->type() == elfcpp::PT_LOAD
)
209 count
+= (*p
)->output_section_count();
213 for (Layout::Section_list::const_iterator p
=
214 this->section_list_
->begin();
215 p
!= this->section_list_
->end();
217 if (((*p
)->flags() & elfcpp::SHF_ALLOC
) != 0)
220 count
+= this->unattached_section_list_
->size();
222 const int size
= parameters
->target().get_size();
225 shdr_size
= elfcpp::Elf_sizes
<32>::shdr_size
;
227 shdr_size
= elfcpp::Elf_sizes
<64>::shdr_size
;
231 return count
* shdr_size
;
234 // Write out the section headers.
237 Output_section_headers::do_write(Output_file
* of
)
239 switch (parameters
->size_and_endianness())
241 #ifdef HAVE_TARGET_32_LITTLE
242 case Parameters::TARGET_32_LITTLE
:
243 this->do_sized_write
<32, false>(of
);
246 #ifdef HAVE_TARGET_32_BIG
247 case Parameters::TARGET_32_BIG
:
248 this->do_sized_write
<32, true>(of
);
251 #ifdef HAVE_TARGET_64_LITTLE
252 case Parameters::TARGET_64_LITTLE
:
253 this->do_sized_write
<64, false>(of
);
256 #ifdef HAVE_TARGET_64_BIG
257 case Parameters::TARGET_64_BIG
:
258 this->do_sized_write
<64, true>(of
);
266 template<int size
, bool big_endian
>
268 Output_section_headers::do_sized_write(Output_file
* of
)
270 off_t all_shdrs_size
= this->data_size();
271 unsigned char* view
= of
->get_output_view(this->offset(), all_shdrs_size
);
273 const int shdr_size
= elfcpp::Elf_sizes
<size
>::shdr_size
;
274 unsigned char* v
= view
;
277 typename
elfcpp::Shdr_write
<size
, big_endian
> oshdr(v
);
278 oshdr
.put_sh_name(0);
279 oshdr
.put_sh_type(elfcpp::SHT_NULL
);
280 oshdr
.put_sh_flags(0);
281 oshdr
.put_sh_addr(0);
282 oshdr
.put_sh_offset(0);
284 size_t section_count
= (this->data_size()
285 / elfcpp::Elf_sizes
<size
>::shdr_size
);
286 if (section_count
< elfcpp::SHN_LORESERVE
)
287 oshdr
.put_sh_size(0);
289 oshdr
.put_sh_size(section_count
);
291 unsigned int shstrndx
= this->shstrtab_section_
->out_shndx();
292 if (shstrndx
< elfcpp::SHN_LORESERVE
)
293 oshdr
.put_sh_link(0);
295 oshdr
.put_sh_link(shstrndx
);
297 size_t segment_count
= this->segment_list_
->size();
298 oshdr
.put_sh_info(segment_count
>= elfcpp::PN_XNUM
? segment_count
: 0);
300 oshdr
.put_sh_addralign(0);
301 oshdr
.put_sh_entsize(0);
306 unsigned int shndx
= 1;
307 if (!parameters
->options().relocatable())
309 for (Layout::Segment_list::const_iterator p
=
310 this->segment_list_
->begin();
311 p
!= this->segment_list_
->end();
313 v
= (*p
)->write_section_headers
<size
, big_endian
>(this->layout_
,
320 for (Layout::Section_list::const_iterator p
=
321 this->section_list_
->begin();
322 p
!= this->section_list_
->end();
325 // We do unallocated sections below, except that group
326 // sections have to come first.
327 if (((*p
)->flags() & elfcpp::SHF_ALLOC
) == 0
328 && (*p
)->type() != elfcpp::SHT_GROUP
)
330 gold_assert(shndx
== (*p
)->out_shndx());
331 elfcpp::Shdr_write
<size
, big_endian
> oshdr(v
);
332 (*p
)->write_header(this->layout_
, this->secnamepool_
, &oshdr
);
338 for (Layout::Section_list::const_iterator p
=
339 this->unattached_section_list_
->begin();
340 p
!= this->unattached_section_list_
->end();
343 // For a relocatable link, we did unallocated group sections
344 // above, since they have to come first.
345 if ((*p
)->type() == elfcpp::SHT_GROUP
346 && parameters
->options().relocatable())
348 gold_assert(shndx
== (*p
)->out_shndx());
349 elfcpp::Shdr_write
<size
, big_endian
> oshdr(v
);
350 (*p
)->write_header(this->layout_
, this->secnamepool_
, &oshdr
);
355 of
->write_output_view(this->offset(), all_shdrs_size
, view
);
358 // Output_segment_header methods.
360 Output_segment_headers::Output_segment_headers(
361 const Layout::Segment_list
& segment_list
)
362 : segment_list_(segment_list
)
364 this->set_current_data_size_for_child(this->do_size());
368 Output_segment_headers::do_write(Output_file
* of
)
370 switch (parameters
->size_and_endianness())
372 #ifdef HAVE_TARGET_32_LITTLE
373 case Parameters::TARGET_32_LITTLE
:
374 this->do_sized_write
<32, false>(of
);
377 #ifdef HAVE_TARGET_32_BIG
378 case Parameters::TARGET_32_BIG
:
379 this->do_sized_write
<32, true>(of
);
382 #ifdef HAVE_TARGET_64_LITTLE
383 case Parameters::TARGET_64_LITTLE
:
384 this->do_sized_write
<64, false>(of
);
387 #ifdef HAVE_TARGET_64_BIG
388 case Parameters::TARGET_64_BIG
:
389 this->do_sized_write
<64, true>(of
);
397 template<int size
, bool big_endian
>
399 Output_segment_headers::do_sized_write(Output_file
* of
)
401 const int phdr_size
= elfcpp::Elf_sizes
<size
>::phdr_size
;
402 off_t all_phdrs_size
= this->segment_list_
.size() * phdr_size
;
403 gold_assert(all_phdrs_size
== this->data_size());
404 unsigned char* view
= of
->get_output_view(this->offset(),
406 unsigned char* v
= view
;
407 for (Layout::Segment_list::const_iterator p
= this->segment_list_
.begin();
408 p
!= this->segment_list_
.end();
411 elfcpp::Phdr_write
<size
, big_endian
> ophdr(v
);
412 (*p
)->write_header(&ophdr
);
416 gold_assert(v
- view
== all_phdrs_size
);
418 of
->write_output_view(this->offset(), all_phdrs_size
, view
);
422 Output_segment_headers::do_size() const
424 const int size
= parameters
->target().get_size();
427 phdr_size
= elfcpp::Elf_sizes
<32>::phdr_size
;
429 phdr_size
= elfcpp::Elf_sizes
<64>::phdr_size
;
433 return this->segment_list_
.size() * phdr_size
;
436 // Output_file_header methods.
438 Output_file_header::Output_file_header(const Target
* target
,
439 const Symbol_table
* symtab
,
440 const Output_segment_headers
* osh
)
443 segment_header_(osh
),
444 section_header_(NULL
),
447 this->set_data_size(this->do_size());
450 // Set the section table information for a file header.
453 Output_file_header::set_section_info(const Output_section_headers
* shdrs
,
454 const Output_section
* shstrtab
)
456 this->section_header_
= shdrs
;
457 this->shstrtab_
= shstrtab
;
460 // Write out the file header.
463 Output_file_header::do_write(Output_file
* of
)
465 gold_assert(this->offset() == 0);
467 switch (parameters
->size_and_endianness())
469 #ifdef HAVE_TARGET_32_LITTLE
470 case Parameters::TARGET_32_LITTLE
:
471 this->do_sized_write
<32, false>(of
);
474 #ifdef HAVE_TARGET_32_BIG
475 case Parameters::TARGET_32_BIG
:
476 this->do_sized_write
<32, true>(of
);
479 #ifdef HAVE_TARGET_64_LITTLE
480 case Parameters::TARGET_64_LITTLE
:
481 this->do_sized_write
<64, false>(of
);
484 #ifdef HAVE_TARGET_64_BIG
485 case Parameters::TARGET_64_BIG
:
486 this->do_sized_write
<64, true>(of
);
494 // Write out the file header with appropriate size and endianness.
496 template<int size
, bool big_endian
>
498 Output_file_header::do_sized_write(Output_file
* of
)
500 gold_assert(this->offset() == 0);
502 int ehdr_size
= elfcpp::Elf_sizes
<size
>::ehdr_size
;
503 unsigned char* view
= of
->get_output_view(0, ehdr_size
);
504 elfcpp::Ehdr_write
<size
, big_endian
> oehdr(view
);
506 unsigned char e_ident
[elfcpp::EI_NIDENT
];
507 memset(e_ident
, 0, elfcpp::EI_NIDENT
);
508 e_ident
[elfcpp::EI_MAG0
] = elfcpp::ELFMAG0
;
509 e_ident
[elfcpp::EI_MAG1
] = elfcpp::ELFMAG1
;
510 e_ident
[elfcpp::EI_MAG2
] = elfcpp::ELFMAG2
;
511 e_ident
[elfcpp::EI_MAG3
] = elfcpp::ELFMAG3
;
513 e_ident
[elfcpp::EI_CLASS
] = elfcpp::ELFCLASS32
;
515 e_ident
[elfcpp::EI_CLASS
] = elfcpp::ELFCLASS64
;
518 e_ident
[elfcpp::EI_DATA
] = (big_endian
519 ? elfcpp::ELFDATA2MSB
520 : elfcpp::ELFDATA2LSB
);
521 e_ident
[elfcpp::EI_VERSION
] = elfcpp::EV_CURRENT
;
522 oehdr
.put_e_ident(e_ident
);
525 if (parameters
->options().relocatable())
526 e_type
= elfcpp::ET_REL
;
527 else if (parameters
->options().output_is_position_independent())
528 e_type
= elfcpp::ET_DYN
;
530 e_type
= elfcpp::ET_EXEC
;
531 oehdr
.put_e_type(e_type
);
533 oehdr
.put_e_machine(this->target_
->machine_code());
534 oehdr
.put_e_version(elfcpp::EV_CURRENT
);
536 oehdr
.put_e_entry(this->entry
<size
>());
538 if (this->segment_header_
== NULL
)
539 oehdr
.put_e_phoff(0);
541 oehdr
.put_e_phoff(this->segment_header_
->offset());
543 oehdr
.put_e_shoff(this->section_header_
->offset());
544 oehdr
.put_e_flags(this->target_
->processor_specific_flags());
545 oehdr
.put_e_ehsize(elfcpp::Elf_sizes
<size
>::ehdr_size
);
547 if (this->segment_header_
== NULL
)
549 oehdr
.put_e_phentsize(0);
550 oehdr
.put_e_phnum(0);
554 oehdr
.put_e_phentsize(elfcpp::Elf_sizes
<size
>::phdr_size
);
555 size_t phnum
= (this->segment_header_
->data_size()
556 / elfcpp::Elf_sizes
<size
>::phdr_size
);
557 if (phnum
> elfcpp::PN_XNUM
)
558 phnum
= elfcpp::PN_XNUM
;
559 oehdr
.put_e_phnum(phnum
);
562 oehdr
.put_e_shentsize(elfcpp::Elf_sizes
<size
>::shdr_size
);
563 size_t section_count
= (this->section_header_
->data_size()
564 / elfcpp::Elf_sizes
<size
>::shdr_size
);
566 if (section_count
< elfcpp::SHN_LORESERVE
)
567 oehdr
.put_e_shnum(this->section_header_
->data_size()
568 / elfcpp::Elf_sizes
<size
>::shdr_size
);
570 oehdr
.put_e_shnum(0);
572 unsigned int shstrndx
= this->shstrtab_
->out_shndx();
573 if (shstrndx
< elfcpp::SHN_LORESERVE
)
574 oehdr
.put_e_shstrndx(this->shstrtab_
->out_shndx());
576 oehdr
.put_e_shstrndx(elfcpp::SHN_XINDEX
);
578 // Let the target adjust the ELF header, e.g., to set EI_OSABI in
579 // the e_ident field.
580 parameters
->target().adjust_elf_header(view
, ehdr_size
);
582 of
->write_output_view(0, ehdr_size
, view
);
585 // Return the value to use for the entry address.
588 typename
elfcpp::Elf_types
<size
>::Elf_Addr
589 Output_file_header::entry()
591 const bool should_issue_warning
= (parameters
->options().entry() != NULL
592 && !parameters
->options().relocatable()
593 && !parameters
->options().shared());
594 const char* entry
= parameters
->entry();
595 Symbol
* sym
= this->symtab_
->lookup(entry
);
597 typename Sized_symbol
<size
>::Value_type v
;
600 Sized_symbol
<size
>* ssym
;
601 ssym
= this->symtab_
->get_sized_symbol
<size
>(sym
);
602 if (!ssym
->is_defined() && should_issue_warning
)
603 gold_warning("entry symbol '%s' exists but is not defined", entry
);
608 // We couldn't find the entry symbol. See if we can parse it as
609 // a number. This supports, e.g., -e 0x1000.
611 v
= strtoull(entry
, &endptr
, 0);
614 if (should_issue_warning
)
615 gold_warning("cannot find entry symbol '%s'", entry
);
623 // Compute the current data size.
626 Output_file_header::do_size() const
628 const int size
= parameters
->target().get_size();
630 return elfcpp::Elf_sizes
<32>::ehdr_size
;
632 return elfcpp::Elf_sizes
<64>::ehdr_size
;
637 // Output_data_const methods.
640 Output_data_const::do_write(Output_file
* of
)
642 of
->write(this->offset(), this->data_
.data(), this->data_
.size());
645 // Output_data_const_buffer methods.
648 Output_data_const_buffer::do_write(Output_file
* of
)
650 of
->write(this->offset(), this->p_
, this->data_size());
653 // Output_section_data methods.
655 // Record the output section, and set the entry size and such.
658 Output_section_data::set_output_section(Output_section
* os
)
660 gold_assert(this->output_section_
== NULL
);
661 this->output_section_
= os
;
662 this->do_adjust_output_section(os
);
665 // Return the section index of the output section.
668 Output_section_data::do_out_shndx() const
670 gold_assert(this->output_section_
!= NULL
);
671 return this->output_section_
->out_shndx();
674 // Set the alignment, which means we may need to update the alignment
675 // of the output section.
678 Output_section_data::set_addralign(uint64_t addralign
)
680 this->addralign_
= addralign
;
681 if (this->output_section_
!= NULL
682 && this->output_section_
->addralign() < addralign
)
683 this->output_section_
->set_addralign(addralign
);
686 // Output_data_strtab methods.
688 // Set the final data size.
691 Output_data_strtab::set_final_data_size()
693 this->strtab_
->set_string_offsets();
694 this->set_data_size(this->strtab_
->get_strtab_size());
697 // Write out a string table.
700 Output_data_strtab::do_write(Output_file
* of
)
702 this->strtab_
->write(of
, this->offset());
705 // Output_reloc methods.
707 // A reloc against a global symbol.
709 template<bool dynamic
, int size
, bool big_endian
>
710 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::Output_reloc(
718 : address_(address
), local_sym_index_(GSYM_CODE
), type_(type
),
719 is_relative_(is_relative
), is_symbolless_(is_symbolless
),
720 is_section_symbol_(false), use_plt_offset_(use_plt_offset
), shndx_(INVALID_CODE
)
722 // this->type_ is a bitfield; make sure TYPE fits.
723 gold_assert(this->type_
== type
);
724 this->u1_
.gsym
= gsym
;
727 this->set_needs_dynsym_index();
730 template<bool dynamic
, int size
, bool big_endian
>
731 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::Output_reloc(
734 Sized_relobj
<size
, big_endian
>* relobj
,
740 : address_(address
), local_sym_index_(GSYM_CODE
), type_(type
),
741 is_relative_(is_relative
), is_symbolless_(is_symbolless
),
742 is_section_symbol_(false), use_plt_offset_(use_plt_offset
), shndx_(shndx
)
744 gold_assert(shndx
!= INVALID_CODE
);
745 // this->type_ is a bitfield; make sure TYPE fits.
746 gold_assert(this->type_
== type
);
747 this->u1_
.gsym
= gsym
;
748 this->u2_
.relobj
= relobj
;
750 this->set_needs_dynsym_index();
753 // A reloc against a local symbol.
755 template<bool dynamic
, int size
, bool big_endian
>
756 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::Output_reloc(
757 Sized_relobj
<size
, big_endian
>* relobj
,
758 unsigned int local_sym_index
,
764 bool is_section_symbol
,
766 : address_(address
), local_sym_index_(local_sym_index
), type_(type
),
767 is_relative_(is_relative
), is_symbolless_(is_symbolless
),
768 is_section_symbol_(is_section_symbol
), use_plt_offset_(use_plt_offset
),
771 gold_assert(local_sym_index
!= GSYM_CODE
772 && local_sym_index
!= INVALID_CODE
);
773 // this->type_ is a bitfield; make sure TYPE fits.
774 gold_assert(this->type_
== type
);
775 this->u1_
.relobj
= relobj
;
778 this->set_needs_dynsym_index();
781 template<bool dynamic
, int size
, bool big_endian
>
782 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::Output_reloc(
783 Sized_relobj
<size
, big_endian
>* relobj
,
784 unsigned int local_sym_index
,
790 bool is_section_symbol
,
792 : address_(address
), local_sym_index_(local_sym_index
), type_(type
),
793 is_relative_(is_relative
), is_symbolless_(is_symbolless
),
794 is_section_symbol_(is_section_symbol
), use_plt_offset_(use_plt_offset
),
797 gold_assert(local_sym_index
!= GSYM_CODE
798 && local_sym_index
!= INVALID_CODE
);
799 gold_assert(shndx
!= INVALID_CODE
);
800 // this->type_ is a bitfield; make sure TYPE fits.
801 gold_assert(this->type_
== type
);
802 this->u1_
.relobj
= relobj
;
803 this->u2_
.relobj
= relobj
;
805 this->set_needs_dynsym_index();
808 // A reloc against the STT_SECTION symbol of an output section.
810 template<bool dynamic
, int size
, bool big_endian
>
811 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::Output_reloc(
817 : address_(address
), local_sym_index_(SECTION_CODE
), type_(type
),
818 is_relative_(is_relative
), is_symbolless_(is_relative
),
819 is_section_symbol_(true), use_plt_offset_(false), shndx_(INVALID_CODE
)
821 // this->type_ is a bitfield; make sure TYPE fits.
822 gold_assert(this->type_
== type
);
826 this->set_needs_dynsym_index();
828 os
->set_needs_symtab_index();
831 template<bool dynamic
, int size
, bool big_endian
>
832 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::Output_reloc(
835 Sized_relobj
<size
, big_endian
>* relobj
,
839 : address_(address
), local_sym_index_(SECTION_CODE
), type_(type
),
840 is_relative_(is_relative
), is_symbolless_(is_relative
),
841 is_section_symbol_(true), use_plt_offset_(false), shndx_(shndx
)
843 gold_assert(shndx
!= INVALID_CODE
);
844 // this->type_ is a bitfield; make sure TYPE fits.
845 gold_assert(this->type_
== type
);
847 this->u2_
.relobj
= relobj
;
849 this->set_needs_dynsym_index();
851 os
->set_needs_symtab_index();
854 // An absolute or relative relocation.
856 template<bool dynamic
, int size
, bool big_endian
>
857 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::Output_reloc(
862 : address_(address
), local_sym_index_(0), type_(type
),
863 is_relative_(is_relative
), is_symbolless_(false),
864 is_section_symbol_(false), use_plt_offset_(false), shndx_(INVALID_CODE
)
866 // this->type_ is a bitfield; make sure TYPE fits.
867 gold_assert(this->type_
== type
);
868 this->u1_
.relobj
= NULL
;
872 template<bool dynamic
, int size
, bool big_endian
>
873 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::Output_reloc(
875 Sized_relobj
<size
, big_endian
>* relobj
,
879 : address_(address
), local_sym_index_(0), type_(type
),
880 is_relative_(is_relative
), is_symbolless_(false),
881 is_section_symbol_(false), use_plt_offset_(false), shndx_(shndx
)
883 gold_assert(shndx
!= INVALID_CODE
);
884 // this->type_ is a bitfield; make sure TYPE fits.
885 gold_assert(this->type_
== type
);
886 this->u1_
.relobj
= NULL
;
887 this->u2_
.relobj
= relobj
;
890 // A target specific relocation.
892 template<bool dynamic
, int size
, bool big_endian
>
893 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::Output_reloc(
898 : address_(address
), local_sym_index_(TARGET_CODE
), type_(type
),
899 is_relative_(false), is_symbolless_(false),
900 is_section_symbol_(false), use_plt_offset_(false), shndx_(INVALID_CODE
)
902 // this->type_ is a bitfield; make sure TYPE fits.
903 gold_assert(this->type_
== type
);
908 template<bool dynamic
, int size
, bool big_endian
>
909 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::Output_reloc(
912 Sized_relobj
<size
, big_endian
>* relobj
,
915 : address_(address
), local_sym_index_(TARGET_CODE
), type_(type
),
916 is_relative_(false), is_symbolless_(false),
917 is_section_symbol_(false), use_plt_offset_(false), shndx_(shndx
)
919 gold_assert(shndx
!= INVALID_CODE
);
920 // this->type_ is a bitfield; make sure TYPE fits.
921 gold_assert(this->type_
== type
);
923 this->u2_
.relobj
= relobj
;
926 // Record that we need a dynamic symbol index for this relocation.
928 template<bool dynamic
, int size
, bool big_endian
>
930 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::
931 set_needs_dynsym_index()
933 if (this->is_symbolless_
)
935 switch (this->local_sym_index_
)
941 this->u1_
.gsym
->set_needs_dynsym_entry();
945 this->u1_
.os
->set_needs_dynsym_index();
949 // The target must take care of this if necessary.
957 const unsigned int lsi
= this->local_sym_index_
;
958 Sized_relobj_file
<size
, big_endian
>* relobj
=
959 this->u1_
.relobj
->sized_relobj();
960 gold_assert(relobj
!= NULL
);
961 if (!this->is_section_symbol_
)
962 relobj
->set_needs_output_dynsym_entry(lsi
);
964 relobj
->output_section(lsi
)->set_needs_dynsym_index();
970 // Get the symbol index of a relocation.
972 template<bool dynamic
, int size
, bool big_endian
>
974 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::get_symbol_index()
978 if (this->is_symbolless_
)
980 switch (this->local_sym_index_
)
986 if (this->u1_
.gsym
== NULL
)
989 index
= this->u1_
.gsym
->dynsym_index();
991 index
= this->u1_
.gsym
->symtab_index();
996 index
= this->u1_
.os
->dynsym_index();
998 index
= this->u1_
.os
->symtab_index();
1002 index
= parameters
->target().reloc_symbol_index(this->u1_
.arg
,
1007 // Relocations without symbols use a symbol index of 0.
1013 const unsigned int lsi
= this->local_sym_index_
;
1014 Sized_relobj_file
<size
, big_endian
>* relobj
=
1015 this->u1_
.relobj
->sized_relobj();
1016 gold_assert(relobj
!= NULL
);
1017 if (!this->is_section_symbol_
)
1020 index
= relobj
->dynsym_index(lsi
);
1022 index
= relobj
->symtab_index(lsi
);
1026 Output_section
* os
= relobj
->output_section(lsi
);
1027 gold_assert(os
!= NULL
);
1029 index
= os
->dynsym_index();
1031 index
= os
->symtab_index();
1036 gold_assert(index
!= -1U);
1040 // For a local section symbol, get the address of the offset ADDEND
1041 // within the input section.
1043 template<bool dynamic
, int size
, bool big_endian
>
1044 typename
elfcpp::Elf_types
<size
>::Elf_Addr
1045 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::
1046 local_section_offset(Addend addend
) const
1048 gold_assert(this->local_sym_index_
!= GSYM_CODE
1049 && this->local_sym_index_
!= SECTION_CODE
1050 && this->local_sym_index_
!= TARGET_CODE
1051 && this->local_sym_index_
!= INVALID_CODE
1052 && this->local_sym_index_
!= 0
1053 && this->is_section_symbol_
);
1054 const unsigned int lsi
= this->local_sym_index_
;
1055 Output_section
* os
= this->u1_
.relobj
->output_section(lsi
);
1056 gold_assert(os
!= NULL
);
1057 Address offset
= this->u1_
.relobj
->get_output_section_offset(lsi
);
1058 if (offset
!= invalid_address
)
1059 return offset
+ addend
;
1060 // This is a merge section.
1061 Sized_relobj_file
<size
, big_endian
>* relobj
=
1062 this->u1_
.relobj
->sized_relobj();
1063 gold_assert(relobj
!= NULL
);
1064 offset
= os
->output_address(relobj
, lsi
, addend
);
1065 gold_assert(offset
!= invalid_address
);
1069 // Get the output address of a relocation.
1071 template<bool dynamic
, int size
, bool big_endian
>
1072 typename
elfcpp::Elf_types
<size
>::Elf_Addr
1073 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::get_address() const
1075 Address address
= this->address_
;
1076 if (this->shndx_
!= INVALID_CODE
)
1078 Output_section
* os
= this->u2_
.relobj
->output_section(this->shndx_
);
1079 gold_assert(os
!= NULL
);
1080 Address off
= this->u2_
.relobj
->get_output_section_offset(this->shndx_
);
1081 if (off
!= invalid_address
)
1082 address
+= os
->address() + off
;
1085 Sized_relobj_file
<size
, big_endian
>* relobj
=
1086 this->u2_
.relobj
->sized_relobj();
1087 gold_assert(relobj
!= NULL
);
1088 address
= os
->output_address(relobj
, this->shndx_
, address
);
1089 gold_assert(address
!= invalid_address
);
1092 else if (this->u2_
.od
!= NULL
)
1093 address
+= this->u2_
.od
->address();
1097 // Write out the offset and info fields of a Rel or Rela relocation
1100 template<bool dynamic
, int size
, bool big_endian
>
1101 template<typename Write_rel
>
1103 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::write_rel(
1104 Write_rel
* wr
) const
1106 wr
->put_r_offset(this->get_address());
1107 unsigned int sym_index
= this->get_symbol_index();
1108 wr
->put_r_info(elfcpp::elf_r_info
<size
>(sym_index
, this->type_
));
1111 // Write out a Rel relocation.
1113 template<bool dynamic
, int size
, bool big_endian
>
1115 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::write(
1116 unsigned char* pov
) const
1118 elfcpp::Rel_write
<size
, big_endian
> orel(pov
);
1119 this->write_rel(&orel
);
1122 // Get the value of the symbol referred to by a Rel relocation.
1124 template<bool dynamic
, int size
, bool big_endian
>
1125 typename
elfcpp::Elf_types
<size
>::Elf_Addr
1126 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::symbol_value(
1127 Addend addend
) const
1129 if (this->local_sym_index_
== GSYM_CODE
)
1131 const Sized_symbol
<size
>* sym
;
1132 sym
= static_cast<const Sized_symbol
<size
>*>(this->u1_
.gsym
);
1133 if (this->use_plt_offset_
&& sym
->has_plt_offset())
1134 return parameters
->target().plt_address_for_global(sym
);
1136 return sym
->value() + addend
;
1138 if (this->local_sym_index_
== SECTION_CODE
)
1140 gold_assert(!this->use_plt_offset_
);
1141 return this->u1_
.os
->address() + addend
;
1143 gold_assert(this->local_sym_index_
!= TARGET_CODE
1144 && this->local_sym_index_
!= INVALID_CODE
1145 && this->local_sym_index_
!= 0
1146 && !this->is_section_symbol_
);
1147 const unsigned int lsi
= this->local_sym_index_
;
1148 Sized_relobj_file
<size
, big_endian
>* relobj
=
1149 this->u1_
.relobj
->sized_relobj();
1150 gold_assert(relobj
!= NULL
);
1151 if (this->use_plt_offset_
)
1152 return parameters
->target().plt_address_for_local(relobj
, lsi
);
1153 const Symbol_value
<size
>* symval
= relobj
->local_symbol(lsi
);
1154 return symval
->value(relobj
, addend
);
1157 // Reloc comparison. This function sorts the dynamic relocs for the
1158 // benefit of the dynamic linker. First we sort all relative relocs
1159 // to the front. Among relative relocs, we sort by output address.
1160 // Among non-relative relocs, we sort by symbol index, then by output
1163 template<bool dynamic
, int size
, bool big_endian
>
1165 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::
1166 compare(const Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>& r2
)
1169 if (this->is_relative_
)
1171 if (!r2
.is_relative_
)
1173 // Otherwise sort by reloc address below.
1175 else if (r2
.is_relative_
)
1179 unsigned int sym1
= this->get_symbol_index();
1180 unsigned int sym2
= r2
.get_symbol_index();
1183 else if (sym1
> sym2
)
1185 // Otherwise sort by reloc address.
1188 section_offset_type addr1
= this->get_address();
1189 section_offset_type addr2
= r2
.get_address();
1192 else if (addr1
> addr2
)
1195 // Final tie breaker, in order to generate the same output on any
1196 // host: reloc type.
1197 unsigned int type1
= this->type_
;
1198 unsigned int type2
= r2
.type_
;
1201 else if (type1
> type2
)
1204 // These relocs appear to be exactly the same.
1208 // Write out a Rela relocation.
1210 template<bool dynamic
, int size
, bool big_endian
>
1212 Output_reloc
<elfcpp::SHT_RELA
, dynamic
, size
, big_endian
>::write(
1213 unsigned char* pov
) const
1215 elfcpp::Rela_write
<size
, big_endian
> orel(pov
);
1216 this->rel_
.write_rel(&orel
);
1217 Addend addend
= this->addend_
;
1218 if (this->rel_
.is_target_specific())
1219 addend
= parameters
->target().reloc_addend(this->rel_
.target_arg(),
1220 this->rel_
.type(), addend
);
1221 else if (this->rel_
.is_symbolless())
1222 addend
= this->rel_
.symbol_value(addend
);
1223 else if (this->rel_
.is_local_section_symbol())
1224 addend
= this->rel_
.local_section_offset(addend
);
1225 orel
.put_r_addend(addend
);
1228 // Output_data_reloc_base methods.
1230 // Adjust the output section.
1232 template<int sh_type
, bool dynamic
, int size
, bool big_endian
>
1234 Output_data_reloc_base
<sh_type
, dynamic
, size
, big_endian
>
1235 ::do_adjust_output_section(Output_section
* os
)
1237 if (sh_type
== elfcpp::SHT_REL
)
1238 os
->set_entsize(elfcpp::Elf_sizes
<size
>::rel_size
);
1239 else if (sh_type
== elfcpp::SHT_RELA
)
1240 os
->set_entsize(elfcpp::Elf_sizes
<size
>::rela_size
);
1244 // A STT_GNU_IFUNC symbol may require a IRELATIVE reloc when doing a
1245 // static link. The backends will generate a dynamic reloc section
1246 // to hold this. In that case we don't want to link to the dynsym
1247 // section, because there isn't one.
1249 os
->set_should_link_to_symtab();
1250 else if (parameters
->doing_static_link())
1253 os
->set_should_link_to_dynsym();
1256 // Write out relocation data.
1258 template<int sh_type
, bool dynamic
, int size
, bool big_endian
>
1260 Output_data_reloc_base
<sh_type
, dynamic
, size
, big_endian
>::do_write(
1263 const off_t off
= this->offset();
1264 const off_t oview_size
= this->data_size();
1265 unsigned char* const oview
= of
->get_output_view(off
, oview_size
);
1267 if (this->sort_relocs())
1269 gold_assert(dynamic
);
1270 std::sort(this->relocs_
.begin(), this->relocs_
.end(),
1271 Sort_relocs_comparison());
1274 unsigned char* pov
= oview
;
1275 for (typename
Relocs::const_iterator p
= this->relocs_
.begin();
1276 p
!= this->relocs_
.end();
1283 gold_assert(pov
- oview
== oview_size
);
1285 of
->write_output_view(off
, oview_size
, oview
);
1287 // We no longer need the relocation entries.
1288 this->relocs_
.clear();
1291 // Class Output_relocatable_relocs.
1293 template<int sh_type
, int size
, bool big_endian
>
1295 Output_relocatable_relocs
<sh_type
, size
, big_endian
>::set_final_data_size()
1297 this->set_data_size(this->rr_
->output_reloc_count()
1298 * Reloc_types
<sh_type
, size
, big_endian
>::reloc_size
);
1301 // class Output_data_group.
1303 template<int size
, bool big_endian
>
1304 Output_data_group
<size
, big_endian
>::Output_data_group(
1305 Sized_relobj_file
<size
, big_endian
>* relobj
,
1306 section_size_type entry_count
,
1307 elfcpp::Elf_Word flags
,
1308 std::vector
<unsigned int>* input_shndxes
)
1309 : Output_section_data(entry_count
* 4, 4, false),
1313 this->input_shndxes_
.swap(*input_shndxes
);
1316 // Write out the section group, which means translating the section
1317 // indexes to apply to the output file.
1319 template<int size
, bool big_endian
>
1321 Output_data_group
<size
, big_endian
>::do_write(Output_file
* of
)
1323 const off_t off
= this->offset();
1324 const section_size_type oview_size
=
1325 convert_to_section_size_type(this->data_size());
1326 unsigned char* const oview
= of
->get_output_view(off
, oview_size
);
1328 elfcpp::Elf_Word
* contents
= reinterpret_cast<elfcpp::Elf_Word
*>(oview
);
1329 elfcpp::Swap
<32, big_endian
>::writeval(contents
, this->flags_
);
1332 for (std::vector
<unsigned int>::const_iterator p
=
1333 this->input_shndxes_
.begin();
1334 p
!= this->input_shndxes_
.end();
1337 Output_section
* os
= this->relobj_
->output_section(*p
);
1339 unsigned int output_shndx
;
1341 output_shndx
= os
->out_shndx();
1344 this->relobj_
->error(_("section group retained but "
1345 "group element discarded"));
1349 elfcpp::Swap
<32, big_endian
>::writeval(contents
, output_shndx
);
1352 size_t wrote
= reinterpret_cast<unsigned char*>(contents
) - oview
;
1353 gold_assert(wrote
== oview_size
);
1355 of
->write_output_view(off
, oview_size
, oview
);
1357 // We no longer need this information.
1358 this->input_shndxes_
.clear();
1361 // Output_data_got::Got_entry methods.
1363 // Write out the entry.
1365 template<int got_size
, bool big_endian
>
1367 Output_data_got
<got_size
, big_endian
>::Got_entry::write(
1368 unsigned int got_indx
,
1369 unsigned char* pov
) const
1373 switch (this->local_sym_index_
)
1377 // If the symbol is resolved locally, we need to write out the
1378 // link-time value, which will be relocated dynamically by a
1379 // RELATIVE relocation.
1380 Symbol
* gsym
= this->u_
.gsym
;
1381 if (this->use_plt_or_tls_offset_
&& gsym
->has_plt_offset())
1382 val
= parameters
->target().plt_address_for_global(gsym
);
1385 switch (parameters
->size_and_endianness())
1387 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
1388 case Parameters::TARGET_32_LITTLE
:
1389 case Parameters::TARGET_32_BIG
:
1391 // This cast is ugly. We don't want to put a
1392 // virtual method in Symbol, because we want Symbol
1393 // to be as small as possible.
1394 Sized_symbol
<32>::Value_type v
;
1395 v
= static_cast<Sized_symbol
<32>*>(gsym
)->value();
1396 val
= convert_types
<Valtype
, Sized_symbol
<32>::Value_type
>(v
);
1400 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
1401 case Parameters::TARGET_64_LITTLE
:
1402 case Parameters::TARGET_64_BIG
:
1404 Sized_symbol
<64>::Value_type v
;
1405 v
= static_cast<Sized_symbol
<64>*>(gsym
)->value();
1406 val
= convert_types
<Valtype
, Sized_symbol
<64>::Value_type
>(v
);
1413 if (this->use_plt_or_tls_offset_
1414 && gsym
->type() == elfcpp::STT_TLS
)
1415 val
+= parameters
->target().tls_offset_for_global(gsym
,
1422 val
= this->u_
.constant
;
1426 // If we're doing an incremental update, don't touch this GOT entry.
1427 if (parameters
->incremental_update())
1429 val
= this->u_
.constant
;
1434 const Relobj
* object
= this->u_
.object
;
1435 const unsigned int lsi
= this->local_sym_index_
;
1436 bool is_tls
= object
->local_is_tls(lsi
);
1437 if (this->use_plt_or_tls_offset_
&& !is_tls
)
1438 val
= parameters
->target().plt_address_for_local(object
, lsi
);
1441 uint64_t lval
= object
->local_symbol_value(lsi
, 0);
1442 val
= convert_types
<Valtype
, uint64_t>(lval
);
1443 if (this->use_plt_or_tls_offset_
&& is_tls
)
1444 val
+= parameters
->target().tls_offset_for_local(object
, lsi
,
1451 elfcpp::Swap
<got_size
, big_endian
>::writeval(pov
, val
);
1454 // Output_data_got methods.
1456 // Add an entry for a global symbol to the GOT. This returns true if
1457 // this is a new GOT entry, false if the symbol already had a GOT
1460 template<int got_size
, bool big_endian
>
1462 Output_data_got
<got_size
, big_endian
>::add_global(
1464 unsigned int got_type
)
1466 if (gsym
->has_got_offset(got_type
))
1469 unsigned int got_offset
= this->add_got_entry(Got_entry(gsym
, false));
1470 gsym
->set_got_offset(got_type
, got_offset
);
1474 // Like add_global, but use the PLT offset.
1476 template<int got_size
, bool big_endian
>
1478 Output_data_got
<got_size
, big_endian
>::add_global_plt(Symbol
* gsym
,
1479 unsigned int got_type
)
1481 if (gsym
->has_got_offset(got_type
))
1484 unsigned int got_offset
= this->add_got_entry(Got_entry(gsym
, true));
1485 gsym
->set_got_offset(got_type
, got_offset
);
1489 // Add an entry for a global symbol to the GOT, and add a dynamic
1490 // relocation of type R_TYPE for the GOT entry.
1492 template<int got_size
, bool big_endian
>
1494 Output_data_got
<got_size
, big_endian
>::add_global_with_rel(
1496 unsigned int got_type
,
1497 Output_data_reloc_generic
* rel_dyn
,
1498 unsigned int r_type
)
1500 if (gsym
->has_got_offset(got_type
))
1503 unsigned int got_offset
= this->add_got_entry(Got_entry());
1504 gsym
->set_got_offset(got_type
, got_offset
);
1505 rel_dyn
->add_global_generic(gsym
, r_type
, this, got_offset
, 0);
1508 // Add a pair of entries for a global symbol to the GOT, and add
1509 // dynamic relocations of type R_TYPE_1 and R_TYPE_2, respectively.
1510 // If R_TYPE_2 == 0, add the second entry with no relocation.
1511 template<int got_size
, bool big_endian
>
1513 Output_data_got
<got_size
, big_endian
>::add_global_pair_with_rel(
1515 unsigned int got_type
,
1516 Output_data_reloc_generic
* rel_dyn
,
1517 unsigned int r_type_1
,
1518 unsigned int r_type_2
)
1520 if (gsym
->has_got_offset(got_type
))
1523 unsigned int got_offset
= this->add_got_entry_pair(Got_entry(), Got_entry());
1524 gsym
->set_got_offset(got_type
, got_offset
);
1525 rel_dyn
->add_global_generic(gsym
, r_type_1
, this, got_offset
, 0);
1528 rel_dyn
->add_global_generic(gsym
, r_type_2
, this,
1529 got_offset
+ got_size
/ 8, 0);
1532 // Add an entry for a local symbol to the GOT. This returns true if
1533 // this is a new GOT entry, false if the symbol already has a GOT
1536 template<int got_size
, bool big_endian
>
1538 Output_data_got
<got_size
, big_endian
>::add_local(
1540 unsigned int symndx
,
1541 unsigned int got_type
)
1543 if (object
->local_has_got_offset(symndx
, got_type
))
1546 unsigned int got_offset
= this->add_got_entry(Got_entry(object
, symndx
,
1548 object
->set_local_got_offset(symndx
, got_type
, got_offset
);
1552 // Like add_local, but use the PLT offset.
1554 template<int got_size
, bool big_endian
>
1556 Output_data_got
<got_size
, big_endian
>::add_local_plt(
1558 unsigned int symndx
,
1559 unsigned int got_type
)
1561 if (object
->local_has_got_offset(symndx
, got_type
))
1564 unsigned int got_offset
= this->add_got_entry(Got_entry(object
, symndx
,
1566 object
->set_local_got_offset(symndx
, got_type
, got_offset
);
1570 // Add an entry for a local symbol to the GOT, and add a dynamic
1571 // relocation of type R_TYPE for the GOT entry.
1573 template<int got_size
, bool big_endian
>
1575 Output_data_got
<got_size
, big_endian
>::add_local_with_rel(
1577 unsigned int symndx
,
1578 unsigned int got_type
,
1579 Output_data_reloc_generic
* rel_dyn
,
1580 unsigned int r_type
)
1582 if (object
->local_has_got_offset(symndx
, got_type
))
1585 unsigned int got_offset
= this->add_got_entry(Got_entry());
1586 object
->set_local_got_offset(symndx
, got_type
, got_offset
);
1587 rel_dyn
->add_local_generic(object
, symndx
, r_type
, this, got_offset
, 0);
1590 // Add a pair of entries for a local symbol to the GOT, and add
1591 // a dynamic relocation of type R_TYPE using the section symbol of
1592 // the output section to which input section SHNDX maps, on the first.
1593 // The first got entry will have a value of zero, the second the
1594 // value of the local symbol.
1595 template<int got_size
, bool big_endian
>
1597 Output_data_got
<got_size
, big_endian
>::add_local_pair_with_rel(
1599 unsigned int symndx
,
1601 unsigned int got_type
,
1602 Output_data_reloc_generic
* rel_dyn
,
1603 unsigned int r_type
)
1605 if (object
->local_has_got_offset(symndx
, got_type
))
1608 unsigned int got_offset
=
1609 this->add_got_entry_pair(Got_entry(),
1610 Got_entry(object
, symndx
, false));
1611 object
->set_local_got_offset(symndx
, got_type
, got_offset
);
1612 Output_section
* os
= object
->output_section(shndx
);
1613 rel_dyn
->add_output_section_generic(os
, r_type
, this, got_offset
, 0);
1616 // Add a pair of entries for a local symbol to the GOT, and add
1617 // a dynamic relocation of type R_TYPE using STN_UNDEF on the first.
1618 // The first got entry will have a value of zero, the second the
1619 // value of the local symbol offset by Target::tls_offset_for_local.
1620 template<int got_size
, bool big_endian
>
1622 Output_data_got
<got_size
, big_endian
>::add_local_tls_pair(
1624 unsigned int symndx
,
1625 unsigned int got_type
,
1626 Output_data_reloc_generic
* rel_dyn
,
1627 unsigned int r_type
)
1629 if (object
->local_has_got_offset(symndx
, got_type
))
1632 unsigned int got_offset
1633 = this->add_got_entry_pair(Got_entry(),
1634 Got_entry(object
, symndx
, true));
1635 object
->set_local_got_offset(symndx
, got_type
, got_offset
);
1636 rel_dyn
->add_local_generic(object
, 0, r_type
, this, got_offset
, 0);
1639 // Reserve a slot in the GOT for a local symbol or the second slot of a pair.
1641 template<int got_size
, bool big_endian
>
1643 Output_data_got
<got_size
, big_endian
>::reserve_local(
1646 unsigned int sym_index
,
1647 unsigned int got_type
)
1649 this->do_reserve_slot(i
);
1650 object
->set_local_got_offset(sym_index
, got_type
, this->got_offset(i
));
1653 // Reserve a slot in the GOT for a global symbol.
1655 template<int got_size
, bool big_endian
>
1657 Output_data_got
<got_size
, big_endian
>::reserve_global(
1660 unsigned int got_type
)
1662 this->do_reserve_slot(i
);
1663 gsym
->set_got_offset(got_type
, this->got_offset(i
));
1666 // Write out the GOT.
1668 template<int got_size
, bool big_endian
>
1670 Output_data_got
<got_size
, big_endian
>::do_write(Output_file
* of
)
1672 const int add
= got_size
/ 8;
1674 const off_t off
= this->offset();
1675 const off_t oview_size
= this->data_size();
1676 unsigned char* const oview
= of
->get_output_view(off
, oview_size
);
1678 unsigned char* pov
= oview
;
1679 for (unsigned int i
= 0; i
< this->entries_
.size(); ++i
)
1681 this->entries_
[i
].write(i
, pov
);
1685 gold_assert(pov
- oview
== oview_size
);
1687 of
->write_output_view(off
, oview_size
, oview
);
1689 // We no longer need the GOT entries.
1690 this->entries_
.clear();
1693 // Create a new GOT entry and return its offset.
1695 template<int got_size
, bool big_endian
>
1697 Output_data_got
<got_size
, big_endian
>::add_got_entry(Got_entry got_entry
)
1699 if (!this->is_data_size_valid())
1701 this->entries_
.push_back(got_entry
);
1702 this->set_got_size();
1703 return this->last_got_offset();
1707 // For an incremental update, find an available slot.
1708 off_t got_offset
= this->free_list_
.allocate(got_size
/ 8,
1710 if (got_offset
== -1)
1711 gold_fallback(_("out of patch space (GOT);"
1712 " relink with --incremental-full"));
1713 unsigned int got_index
= got_offset
/ (got_size
/ 8);
1714 gold_assert(got_index
< this->entries_
.size());
1715 this->entries_
[got_index
] = got_entry
;
1716 return static_cast<unsigned int>(got_offset
);
1720 // Create a pair of new GOT entries and return the offset of the first.
1722 template<int got_size
, bool big_endian
>
1724 Output_data_got
<got_size
, big_endian
>::add_got_entry_pair(
1725 Got_entry got_entry_1
,
1726 Got_entry got_entry_2
)
1728 if (!this->is_data_size_valid())
1730 unsigned int got_offset
;
1731 this->entries_
.push_back(got_entry_1
);
1732 got_offset
= this->last_got_offset();
1733 this->entries_
.push_back(got_entry_2
);
1734 this->set_got_size();
1739 // For an incremental update, find an available pair of slots.
1740 off_t got_offset
= this->free_list_
.allocate(2 * got_size
/ 8,
1742 if (got_offset
== -1)
1743 gold_fallback(_("out of patch space (GOT);"
1744 " relink with --incremental-full"));
1745 unsigned int got_index
= got_offset
/ (got_size
/ 8);
1746 gold_assert(got_index
< this->entries_
.size());
1747 this->entries_
[got_index
] = got_entry_1
;
1748 this->entries_
[got_index
+ 1] = got_entry_2
;
1749 return static_cast<unsigned int>(got_offset
);
1753 // Replace GOT entry I with a new value.
1755 template<int got_size
, bool big_endian
>
1757 Output_data_got
<got_size
, big_endian
>::replace_got_entry(
1759 Got_entry got_entry
)
1761 gold_assert(i
< this->entries_
.size());
1762 this->entries_
[i
] = got_entry
;
1765 // Output_data_dynamic::Dynamic_entry methods.
1767 // Write out the entry.
1769 template<int size
, bool big_endian
>
1771 Output_data_dynamic::Dynamic_entry::write(
1773 const Stringpool
* pool
) const
1775 typename
elfcpp::Elf_types
<size
>::Elf_WXword val
;
1776 switch (this->offset_
)
1778 case DYNAMIC_NUMBER
:
1782 case DYNAMIC_SECTION_SIZE
:
1783 val
= this->u_
.od
->data_size();
1784 if (this->od2
!= NULL
)
1785 val
+= this->od2
->data_size();
1788 case DYNAMIC_SYMBOL
:
1790 const Sized_symbol
<size
>* s
=
1791 static_cast<const Sized_symbol
<size
>*>(this->u_
.sym
);
1796 case DYNAMIC_STRING
:
1797 val
= pool
->get_offset(this->u_
.str
);
1801 val
= this->u_
.od
->address() + this->offset_
;
1805 elfcpp::Dyn_write
<size
, big_endian
> dw(pov
);
1806 dw
.put_d_tag(this->tag_
);
1810 // Output_data_dynamic methods.
1812 // Adjust the output section to set the entry size.
1815 Output_data_dynamic::do_adjust_output_section(Output_section
* os
)
1817 if (parameters
->target().get_size() == 32)
1818 os
->set_entsize(elfcpp::Elf_sizes
<32>::dyn_size
);
1819 else if (parameters
->target().get_size() == 64)
1820 os
->set_entsize(elfcpp::Elf_sizes
<64>::dyn_size
);
1825 // Set the final data size.
1828 Output_data_dynamic::set_final_data_size()
1830 // Add the terminating entry if it hasn't been added.
1831 // Because of relaxation, we can run this multiple times.
1832 if (this->entries_
.empty() || this->entries_
.back().tag() != elfcpp::DT_NULL
)
1834 int extra
= parameters
->options().spare_dynamic_tags();
1835 for (int i
= 0; i
< extra
; ++i
)
1836 this->add_constant(elfcpp::DT_NULL
, 0);
1837 this->add_constant(elfcpp::DT_NULL
, 0);
1841 if (parameters
->target().get_size() == 32)
1842 dyn_size
= elfcpp::Elf_sizes
<32>::dyn_size
;
1843 else if (parameters
->target().get_size() == 64)
1844 dyn_size
= elfcpp::Elf_sizes
<64>::dyn_size
;
1847 this->set_data_size(this->entries_
.size() * dyn_size
);
1850 // Write out the dynamic entries.
1853 Output_data_dynamic::do_write(Output_file
* of
)
1855 switch (parameters
->size_and_endianness())
1857 #ifdef HAVE_TARGET_32_LITTLE
1858 case Parameters::TARGET_32_LITTLE
:
1859 this->sized_write
<32, false>(of
);
1862 #ifdef HAVE_TARGET_32_BIG
1863 case Parameters::TARGET_32_BIG
:
1864 this->sized_write
<32, true>(of
);
1867 #ifdef HAVE_TARGET_64_LITTLE
1868 case Parameters::TARGET_64_LITTLE
:
1869 this->sized_write
<64, false>(of
);
1872 #ifdef HAVE_TARGET_64_BIG
1873 case Parameters::TARGET_64_BIG
:
1874 this->sized_write
<64, true>(of
);
1882 template<int size
, bool big_endian
>
1884 Output_data_dynamic::sized_write(Output_file
* of
)
1886 const int dyn_size
= elfcpp::Elf_sizes
<size
>::dyn_size
;
1888 const off_t offset
= this->offset();
1889 const off_t oview_size
= this->data_size();
1890 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
1892 unsigned char* pov
= oview
;
1893 for (typename
Dynamic_entries::const_iterator p
= this->entries_
.begin();
1894 p
!= this->entries_
.end();
1897 p
->write
<size
, big_endian
>(pov
, this->pool_
);
1901 gold_assert(pov
- oview
== oview_size
);
1903 of
->write_output_view(offset
, oview_size
, oview
);
1905 // We no longer need the dynamic entries.
1906 this->entries_
.clear();
1909 // Class Output_symtab_xindex.
1912 Output_symtab_xindex::do_write(Output_file
* of
)
1914 const off_t offset
= this->offset();
1915 const off_t oview_size
= this->data_size();
1916 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
1918 memset(oview
, 0, oview_size
);
1920 if (parameters
->target().is_big_endian())
1921 this->endian_do_write
<true>(oview
);
1923 this->endian_do_write
<false>(oview
);
1925 of
->write_output_view(offset
, oview_size
, oview
);
1927 // We no longer need the data.
1928 this->entries_
.clear();
1931 template<bool big_endian
>
1933 Output_symtab_xindex::endian_do_write(unsigned char* const oview
)
1935 for (Xindex_entries::const_iterator p
= this->entries_
.begin();
1936 p
!= this->entries_
.end();
1939 unsigned int symndx
= p
->first
;
1940 gold_assert(static_cast<off_t
>(symndx
) * 4 < this->data_size());
1941 elfcpp::Swap
<32, big_endian
>::writeval(oview
+ symndx
* 4, p
->second
);
1945 // Output_fill_debug_info methods.
1947 // Return the minimum size needed for a dummy compilation unit header.
1950 Output_fill_debug_info::do_minimum_hole_size() const
1952 // Compile unit header fields: unit_length, version, debug_abbrev_offset,
1954 const size_t len
= 4 + 2 + 4 + 1;
1955 // For type units, add type_signature, type_offset.
1956 if (this->is_debug_types_
)
1961 // Write a dummy compilation unit header to fill a hole in the
1962 // .debug_info or .debug_types section.
1965 Output_fill_debug_info::do_write(Output_file
* of
, off_t off
, size_t len
) const
1967 gold_debug(DEBUG_INCREMENTAL
, "fill_debug_info(%08lx, %08lx)",
1968 static_cast<long>(off
), static_cast<long>(len
));
1970 gold_assert(len
>= this->do_minimum_hole_size());
1972 unsigned char* const oview
= of
->get_output_view(off
, len
);
1973 unsigned char* pov
= oview
;
1975 // Write header fields: unit_length, version, debug_abbrev_offset,
1977 if (this->is_big_endian())
1979 elfcpp::Swap_unaligned
<32, true>::writeval(pov
, len
- 4);
1980 elfcpp::Swap_unaligned
<16, true>::writeval(pov
+ 4, this->version
);
1981 elfcpp::Swap_unaligned
<32, true>::writeval(pov
+ 6, 0);
1985 elfcpp::Swap_unaligned
<32, false>::writeval(pov
, len
- 4);
1986 elfcpp::Swap_unaligned
<16, false>::writeval(pov
+ 4, this->version
);
1987 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 6, 0);
1992 // For type units, the additional header fields -- type_signature,
1993 // type_offset -- can be filled with zeroes.
1995 // Fill the remainder of the free space with zeroes. The first
1996 // zero should tell the consumer there are no DIEs to read in this
1997 // compilation unit.
1998 if (pov
< oview
+ len
)
1999 memset(pov
, 0, oview
+ len
- pov
);
2001 of
->write_output_view(off
, len
, oview
);
2004 // Output_fill_debug_line methods.
2006 // Return the minimum size needed for a dummy line number program header.
2009 Output_fill_debug_line::do_minimum_hole_size() const
2011 // Line number program header fields: unit_length, version, header_length,
2012 // minimum_instruction_length, default_is_stmt, line_base, line_range,
2013 // opcode_base, standard_opcode_lengths[], include_directories, filenames.
2014 const size_t len
= 4 + 2 + 4 + this->header_length
;
2018 // Write a dummy line number program header to fill a hole in the
2019 // .debug_line section.
2022 Output_fill_debug_line::do_write(Output_file
* of
, off_t off
, size_t len
) const
2024 gold_debug(DEBUG_INCREMENTAL
, "fill_debug_line(%08lx, %08lx)",
2025 static_cast<long>(off
), static_cast<long>(len
));
2027 gold_assert(len
>= this->do_minimum_hole_size());
2029 unsigned char* const oview
= of
->get_output_view(off
, len
);
2030 unsigned char* pov
= oview
;
2032 // Write header fields: unit_length, version, header_length,
2033 // minimum_instruction_length, default_is_stmt, line_base, line_range,
2034 // opcode_base, standard_opcode_lengths[], include_directories, filenames.
2035 // We set the header_length field to cover the entire hole, so the
2036 // line number program is empty.
2037 if (this->is_big_endian())
2039 elfcpp::Swap_unaligned
<32, true>::writeval(pov
, len
- 4);
2040 elfcpp::Swap_unaligned
<16, true>::writeval(pov
+ 4, this->version
);
2041 elfcpp::Swap_unaligned
<32, true>::writeval(pov
+ 6, len
- (4 + 2 + 4));
2045 elfcpp::Swap_unaligned
<32, false>::writeval(pov
, len
- 4);
2046 elfcpp::Swap_unaligned
<16, false>::writeval(pov
+ 4, this->version
);
2047 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 6, len
- (4 + 2 + 4));
2050 *pov
++ = 1; // minimum_instruction_length
2051 *pov
++ = 0; // default_is_stmt
2052 *pov
++ = 0; // line_base
2053 *pov
++ = 5; // line_range
2054 *pov
++ = 13; // opcode_base
2055 *pov
++ = 0; // standard_opcode_lengths[1]
2056 *pov
++ = 1; // standard_opcode_lengths[2]
2057 *pov
++ = 1; // standard_opcode_lengths[3]
2058 *pov
++ = 1; // standard_opcode_lengths[4]
2059 *pov
++ = 1; // standard_opcode_lengths[5]
2060 *pov
++ = 0; // standard_opcode_lengths[6]
2061 *pov
++ = 0; // standard_opcode_lengths[7]
2062 *pov
++ = 0; // standard_opcode_lengths[8]
2063 *pov
++ = 1; // standard_opcode_lengths[9]
2064 *pov
++ = 0; // standard_opcode_lengths[10]
2065 *pov
++ = 0; // standard_opcode_lengths[11]
2066 *pov
++ = 1; // standard_opcode_lengths[12]
2067 *pov
++ = 0; // include_directories (empty)
2068 *pov
++ = 0; // filenames (empty)
2070 // Some consumers don't check the header_length field, and simply
2071 // start reading the line number program immediately following the
2072 // header. For those consumers, we fill the remainder of the free
2073 // space with DW_LNS_set_basic_block opcodes. These are effectively
2074 // no-ops: the resulting line table program will not create any rows.
2075 if (pov
< oview
+ len
)
2076 memset(pov
, elfcpp::DW_LNS_set_basic_block
, oview
+ len
- pov
);
2078 of
->write_output_view(off
, len
, oview
);
2081 // Output_section::Input_section methods.
2083 // Return the current data size. For an input section we store the size here.
2084 // For an Output_section_data, we have to ask it for the size.
2087 Output_section::Input_section::current_data_size() const
2089 if (this->is_input_section())
2090 return this->u1_
.data_size
;
2093 this->u2_
.posd
->pre_finalize_data_size();
2094 return this->u2_
.posd
->current_data_size();
2098 // Return the data size. For an input section we store the size here.
2099 // For an Output_section_data, we have to ask it for the size.
2102 Output_section::Input_section::data_size() const
2104 if (this->is_input_section())
2105 return this->u1_
.data_size
;
2107 return this->u2_
.posd
->data_size();
2110 // Return the object for an input section.
2113 Output_section::Input_section::relobj() const
2115 if (this->is_input_section())
2116 return this->u2_
.object
;
2117 else if (this->is_merge_section())
2119 gold_assert(this->u2_
.pomb
->first_relobj() != NULL
);
2120 return this->u2_
.pomb
->first_relobj();
2122 else if (this->is_relaxed_input_section())
2123 return this->u2_
.poris
->relobj();
2128 // Return the input section index for an input section.
2131 Output_section::Input_section::shndx() const
2133 if (this->is_input_section())
2134 return this->shndx_
;
2135 else if (this->is_merge_section())
2137 gold_assert(this->u2_
.pomb
->first_relobj() != NULL
);
2138 return this->u2_
.pomb
->first_shndx();
2140 else if (this->is_relaxed_input_section())
2141 return this->u2_
.poris
->shndx();
2146 // Set the address and file offset.
2149 Output_section::Input_section::set_address_and_file_offset(
2152 off_t section_file_offset
)
2154 if (this->is_input_section())
2155 this->u2_
.object
->set_section_offset(this->shndx_
,
2156 file_offset
- section_file_offset
);
2158 this->u2_
.posd
->set_address_and_file_offset(address
, file_offset
);
2161 // Reset the address and file offset.
2164 Output_section::Input_section::reset_address_and_file_offset()
2166 if (!this->is_input_section())
2167 this->u2_
.posd
->reset_address_and_file_offset();
2170 // Finalize the data size.
2173 Output_section::Input_section::finalize_data_size()
2175 if (!this->is_input_section())
2176 this->u2_
.posd
->finalize_data_size();
2179 // Try to turn an input offset into an output offset. We want to
2180 // return the output offset relative to the start of this
2181 // Input_section in the output section.
2184 Output_section::Input_section::output_offset(
2185 const Relobj
* object
,
2187 section_offset_type offset
,
2188 section_offset_type
* poutput
) const
2190 if (!this->is_input_section())
2191 return this->u2_
.posd
->output_offset(object
, shndx
, offset
, poutput
);
2194 if (this->shndx_
!= shndx
|| this->u2_
.object
!= object
)
2201 // Return whether this is the merge section for the input section
2205 Output_section::Input_section::is_merge_section_for(const Relobj
* object
,
2206 unsigned int shndx
) const
2208 if (this->is_input_section())
2210 return this->u2_
.posd
->is_merge_section_for(object
, shndx
);
2213 // Write out the data. We don't have to do anything for an input
2214 // section--they are handled via Object::relocate--but this is where
2215 // we write out the data for an Output_section_data.
2218 Output_section::Input_section::write(Output_file
* of
)
2220 if (!this->is_input_section())
2221 this->u2_
.posd
->write(of
);
2224 // Write the data to a buffer. As for write(), we don't have to do
2225 // anything for an input section.
2228 Output_section::Input_section::write_to_buffer(unsigned char* buffer
)
2230 if (!this->is_input_section())
2231 this->u2_
.posd
->write_to_buffer(buffer
);
2234 // Print to a map file.
2237 Output_section::Input_section::print_to_mapfile(Mapfile
* mapfile
) const
2239 switch (this->shndx_
)
2241 case OUTPUT_SECTION_CODE
:
2242 case MERGE_DATA_SECTION_CODE
:
2243 case MERGE_STRING_SECTION_CODE
:
2244 this->u2_
.posd
->print_to_mapfile(mapfile
);
2247 case RELAXED_INPUT_SECTION_CODE
:
2249 Output_relaxed_input_section
* relaxed_section
=
2250 this->relaxed_input_section();
2251 mapfile
->print_input_section(relaxed_section
->relobj(),
2252 relaxed_section
->shndx());
2256 mapfile
->print_input_section(this->u2_
.object
, this->shndx_
);
2261 // Output_section methods.
2263 // Construct an Output_section. NAME will point into a Stringpool.
2265 Output_section::Output_section(const char* name
, elfcpp::Elf_Word type
,
2266 elfcpp::Elf_Xword flags
)
2271 link_section_(NULL
),
2273 info_section_(NULL
),
2278 order_(ORDER_INVALID
),
2283 first_input_offset_(0),
2285 postprocessing_buffer_(NULL
),
2286 needs_symtab_index_(false),
2287 needs_dynsym_index_(false),
2288 should_link_to_symtab_(false),
2289 should_link_to_dynsym_(false),
2290 after_input_sections_(false),
2291 requires_postprocessing_(false),
2292 found_in_sections_clause_(false),
2293 has_load_address_(false),
2294 info_uses_section_index_(false),
2295 input_section_order_specified_(false),
2296 may_sort_attached_input_sections_(false),
2297 must_sort_attached_input_sections_(false),
2298 attached_input_sections_are_sorted_(false),
2300 is_small_section_(false),
2301 is_large_section_(false),
2302 generate_code_fills_at_write_(false),
2303 is_entsize_zero_(false),
2304 section_offsets_need_adjustment_(false),
2306 always_keeps_input_sections_(false),
2307 has_fixed_layout_(false),
2308 is_patch_space_allowed_(false),
2309 is_unique_segment_(false),
2311 extra_segment_flags_(0),
2312 segment_alignment_(0),
2314 lookup_maps_(new Output_section_lookup_maps
),
2316 free_space_fill_(NULL
),
2319 // An unallocated section has no address. Forcing this means that
2320 // we don't need special treatment for symbols defined in debug
2322 if ((flags
& elfcpp::SHF_ALLOC
) == 0)
2323 this->set_address(0);
2326 Output_section::~Output_section()
2328 delete this->checkpoint_
;
2331 // Set the entry size.
2334 Output_section::set_entsize(uint64_t v
)
2336 if (this->is_entsize_zero_
)
2338 else if (this->entsize_
== 0)
2340 else if (this->entsize_
!= v
)
2343 this->is_entsize_zero_
= 1;
2347 // Add the input section SHNDX, with header SHDR, named SECNAME, in
2348 // OBJECT, to the Output_section. RELOC_SHNDX is the index of a
2349 // relocation section which applies to this section, or 0 if none, or
2350 // -1U if more than one. Return the offset of the input section
2351 // within the output section. Return -1 if the input section will
2352 // receive special handling. In the normal case we don't always keep
2353 // track of input sections for an Output_section. Instead, each
2354 // Object keeps track of the Output_section for each of its input
2355 // sections. However, if HAVE_SECTIONS_SCRIPT is true, we do keep
2356 // track of input sections here; this is used when SECTIONS appears in
2359 template<int size
, bool big_endian
>
2361 Output_section::add_input_section(Layout
* layout
,
2362 Sized_relobj_file
<size
, big_endian
>* object
,
2364 const char* secname
,
2365 const elfcpp::Shdr
<size
, big_endian
>& shdr
,
2366 unsigned int reloc_shndx
,
2367 bool have_sections_script
)
2369 elfcpp::Elf_Xword addralign
= shdr
.get_sh_addralign();
2370 if ((addralign
& (addralign
- 1)) != 0)
2372 object
->error(_("invalid alignment %lu for section \"%s\""),
2373 static_cast<unsigned long>(addralign
), secname
);
2377 if (addralign
> this->addralign_
)
2378 this->addralign_
= addralign
;
2380 typename
elfcpp::Elf_types
<size
>::Elf_WXword sh_flags
= shdr
.get_sh_flags();
2381 uint64_t entsize
= shdr
.get_sh_entsize();
2383 // .debug_str is a mergeable string section, but is not always so
2384 // marked by compilers. Mark manually here so we can optimize.
2385 if (strcmp(secname
, ".debug_str") == 0)
2387 sh_flags
|= (elfcpp::SHF_MERGE
| elfcpp::SHF_STRINGS
);
2391 this->update_flags_for_input_section(sh_flags
);
2392 this->set_entsize(entsize
);
2394 // If this is a SHF_MERGE section, we pass all the input sections to
2395 // a Output_data_merge. We don't try to handle relocations for such
2396 // a section. We don't try to handle empty merge sections--they
2397 // mess up the mappings, and are useless anyhow.
2398 // FIXME: Need to handle merge sections during incremental update.
2399 if ((sh_flags
& elfcpp::SHF_MERGE
) != 0
2401 && shdr
.get_sh_size() > 0
2402 && !parameters
->incremental())
2404 // Keep information about merged input sections for rebuilding fast
2405 // lookup maps if we have sections-script or we do relaxation.
2406 bool keeps_input_sections
= (this->always_keeps_input_sections_
2407 || have_sections_script
2408 || parameters
->target().may_relax());
2410 if (this->add_merge_input_section(object
, shndx
, sh_flags
, entsize
,
2411 addralign
, keeps_input_sections
))
2413 // Tell the relocation routines that they need to call the
2414 // output_offset method to determine the final address.
2419 section_size_type input_section_size
= shdr
.get_sh_size();
2420 section_size_type uncompressed_size
;
2421 if (object
->section_is_compressed(shndx
, &uncompressed_size
))
2422 input_section_size
= uncompressed_size
;
2424 off_t offset_in_section
;
2425 off_t aligned_offset_in_section
;
2426 if (this->has_fixed_layout())
2428 // For incremental updates, find a chunk of unused space in the section.
2429 offset_in_section
= this->free_list_
.allocate(input_section_size
,
2431 if (offset_in_section
== -1)
2432 gold_fallback(_("out of patch space in section %s; "
2433 "relink with --incremental-full"),
2435 aligned_offset_in_section
= offset_in_section
;
2439 offset_in_section
= this->current_data_size_for_child();
2440 aligned_offset_in_section
= align_address(offset_in_section
,
2442 this->set_current_data_size_for_child(aligned_offset_in_section
2443 + input_section_size
);
2446 // Determine if we want to delay code-fill generation until the output
2447 // section is written. When the target is relaxing, we want to delay fill
2448 // generating to avoid adjusting them during relaxation. Also, if we are
2449 // sorting input sections we must delay fill generation.
2450 if (!this->generate_code_fills_at_write_
2451 && !have_sections_script
2452 && (sh_flags
& elfcpp::SHF_EXECINSTR
) != 0
2453 && parameters
->target().has_code_fill()
2454 && (parameters
->target().may_relax()
2455 || layout
->is_section_ordering_specified()))
2457 gold_assert(this->fills_
.empty());
2458 this->generate_code_fills_at_write_
= true;
2461 if (aligned_offset_in_section
> offset_in_section
2462 && !this->generate_code_fills_at_write_
2463 && !have_sections_script
2464 && (sh_flags
& elfcpp::SHF_EXECINSTR
) != 0
2465 && parameters
->target().has_code_fill())
2467 // We need to add some fill data. Using fill_list_ when
2468 // possible is an optimization, since we will often have fill
2469 // sections without input sections.
2470 off_t fill_len
= aligned_offset_in_section
- offset_in_section
;
2471 if (this->input_sections_
.empty())
2472 this->fills_
.push_back(Fill(offset_in_section
, fill_len
));
2475 std::string
fill_data(parameters
->target().code_fill(fill_len
));
2476 Output_data_const
* odc
= new Output_data_const(fill_data
, 1);
2477 this->input_sections_
.push_back(Input_section(odc
));
2481 // The GNU linker groups input sections whose names match .text.unlikely.*.
2482 // This is used to get better code layout. We are compatible.
2483 // Additionally, it could also be beneficial to group .text.hot.*,
2484 // .text.startup.* prefixed input sections. Function
2485 // "is_section_name_prefix_grouped" in layout.cc determines the input
2486 // section prefixes that must be grouped.
2487 if (!have_sections_script
2488 && !parameters
->options().relocatable()
2489 && !this->input_section_order_specified()
2490 && !this->must_sort_attached_input_sections()
2491 && layout
->is_section_name_prefix_grouped(secname
))
2492 this->set_input_section_order_specified();
2494 // We need to keep track of this section if we are already keeping
2495 // track of sections, or if we are relaxing. Also, if this is a
2496 // section which requires sorting, or which may require sorting in
2497 // the future, we keep track of the sections. If the
2498 // --section-ordering-file option is used to specify the order of
2499 // sections, we need to keep track of sections.
2500 if (this->always_keeps_input_sections_
2501 || have_sections_script
2502 || !this->input_sections_
.empty()
2503 || this->may_sort_attached_input_sections()
2504 || this->must_sort_attached_input_sections()
2505 || parameters
->options().user_set_Map()
2506 || parameters
->target().may_relax()
2507 || layout
->is_section_ordering_specified()
2508 || this->input_section_order_specified())
2510 Input_section
isecn(object
, shndx
, input_section_size
, addralign
);
2511 /* If section ordering is requested by specifying a ordering file,
2512 using --section-ordering-file, match the section name with
2514 if (parameters
->options().section_ordering_file())
2516 unsigned int section_order_index
=
2517 layout
->find_section_order_index(std::string(secname
));
2518 if (section_order_index
!= 0)
2520 isecn
.set_section_order_index(section_order_index
);
2521 this->set_input_section_order_specified();
2524 if (this->has_fixed_layout())
2526 // For incremental updates, finalize the address and offset now.
2527 uint64_t addr
= this->address();
2528 isecn
.set_address_and_file_offset(addr
+ aligned_offset_in_section
,
2529 aligned_offset_in_section
,
2532 this->input_sections_
.push_back(isecn
);
2535 return aligned_offset_in_section
;
2538 // Add arbitrary data to an output section.
2541 Output_section::add_output_section_data(Output_section_data
* posd
)
2543 Input_section
inp(posd
);
2544 this->add_output_section_data(&inp
);
2546 if (posd
->is_data_size_valid())
2548 off_t offset_in_section
;
2549 if (this->has_fixed_layout())
2551 // For incremental updates, find a chunk of unused space.
2552 offset_in_section
= this->free_list_
.allocate(posd
->data_size(),
2553 posd
->addralign(), 0);
2554 if (offset_in_section
== -1)
2555 gold_fallback(_("out of patch space in section %s; "
2556 "relink with --incremental-full"),
2558 // Finalize the address and offset now.
2559 uint64_t addr
= this->address();
2560 off_t offset
= this->offset();
2561 posd
->set_address_and_file_offset(addr
+ offset_in_section
,
2562 offset
+ offset_in_section
);
2566 offset_in_section
= this->current_data_size_for_child();
2567 off_t aligned_offset_in_section
= align_address(offset_in_section
,
2569 this->set_current_data_size_for_child(aligned_offset_in_section
2570 + posd
->data_size());
2573 else if (this->has_fixed_layout())
2575 // For incremental updates, arrange for the data to have a fixed layout.
2576 // This will mean that additions to the data must be allocated from
2577 // free space within the containing output section.
2578 uint64_t addr
= this->address();
2579 posd
->set_address(addr
);
2580 posd
->set_file_offset(0);
2581 // FIXME: This should eventually be unreachable.
2582 // gold_unreachable();
2586 // Add a relaxed input section.
2589 Output_section::add_relaxed_input_section(Layout
* layout
,
2590 Output_relaxed_input_section
* poris
,
2591 const std::string
& name
)
2593 Input_section
inp(poris
);
2595 // If the --section-ordering-file option is used to specify the order of
2596 // sections, we need to keep track of sections.
2597 if (layout
->is_section_ordering_specified())
2599 unsigned int section_order_index
=
2600 layout
->find_section_order_index(name
);
2601 if (section_order_index
!= 0)
2603 inp
.set_section_order_index(section_order_index
);
2604 this->set_input_section_order_specified();
2608 this->add_output_section_data(&inp
);
2609 if (this->lookup_maps_
->is_valid())
2610 this->lookup_maps_
->add_relaxed_input_section(poris
->relobj(),
2611 poris
->shndx(), poris
);
2613 // For a relaxed section, we use the current data size. Linker scripts
2614 // get all the input sections, including relaxed one from an output
2615 // section and add them back to the same output section to compute the
2616 // output section size. If we do not account for sizes of relaxed input
2617 // sections, an output section would be incorrectly sized.
2618 off_t offset_in_section
= this->current_data_size_for_child();
2619 off_t aligned_offset_in_section
= align_address(offset_in_section
,
2620 poris
->addralign());
2621 this->set_current_data_size_for_child(aligned_offset_in_section
2622 + poris
->current_data_size());
2625 // Add arbitrary data to an output section by Input_section.
2628 Output_section::add_output_section_data(Input_section
* inp
)
2630 if (this->input_sections_
.empty())
2631 this->first_input_offset_
= this->current_data_size_for_child();
2633 this->input_sections_
.push_back(*inp
);
2635 uint64_t addralign
= inp
->addralign();
2636 if (addralign
> this->addralign_
)
2637 this->addralign_
= addralign
;
2639 inp
->set_output_section(this);
2642 // Add a merge section to an output section.
2645 Output_section::add_output_merge_section(Output_section_data
* posd
,
2646 bool is_string
, uint64_t entsize
)
2648 Input_section
inp(posd
, is_string
, entsize
);
2649 this->add_output_section_data(&inp
);
2652 // Add an input section to a SHF_MERGE section.
2655 Output_section::add_merge_input_section(Relobj
* object
, unsigned int shndx
,
2656 uint64_t flags
, uint64_t entsize
,
2658 bool keeps_input_sections
)
2660 bool is_string
= (flags
& elfcpp::SHF_STRINGS
) != 0;
2662 // We only merge strings if the alignment is not more than the
2663 // character size. This could be handled, but it's unusual.
2664 if (is_string
&& addralign
> entsize
)
2667 // We cannot restore merged input section states.
2668 gold_assert(this->checkpoint_
== NULL
);
2670 // Look up merge sections by required properties.
2671 // Currently, we only invalidate the lookup maps in script processing
2672 // and relaxation. We should not have done either when we reach here.
2673 // So we assume that the lookup maps are valid to simply code.
2674 gold_assert(this->lookup_maps_
->is_valid());
2675 Merge_section_properties
msp(is_string
, entsize
, addralign
);
2676 Output_merge_base
* pomb
= this->lookup_maps_
->find_merge_section(msp
);
2677 bool is_new
= false;
2680 gold_assert(pomb
->is_string() == is_string
2681 && pomb
->entsize() == entsize
2682 && pomb
->addralign() == addralign
);
2686 // Create a new Output_merge_data or Output_merge_string_data.
2688 pomb
= new Output_merge_data(entsize
, addralign
);
2694 pomb
= new Output_merge_string
<char>(addralign
);
2697 pomb
= new Output_merge_string
<uint16_t>(addralign
);
2700 pomb
= new Output_merge_string
<uint32_t>(addralign
);
2706 // If we need to do script processing or relaxation, we need to keep
2707 // the original input sections to rebuild the fast lookup maps.
2708 if (keeps_input_sections
)
2709 pomb
->set_keeps_input_sections();
2713 if (pomb
->add_input_section(object
, shndx
))
2715 // Add new merge section to this output section and link merge
2716 // section properties to new merge section in map.
2719 this->add_output_merge_section(pomb
, is_string
, entsize
);
2720 this->lookup_maps_
->add_merge_section(msp
, pomb
);
2723 // Add input section to new merge section and link input section to new
2724 // merge section in map.
2725 this->lookup_maps_
->add_merge_input_section(object
, shndx
, pomb
);
2730 // If add_input_section failed, delete new merge section to avoid
2731 // exporting empty merge sections in Output_section::get_input_section.
2738 // Build a relaxation map to speed up relaxation of existing input sections.
2739 // Look up to the first LIMIT elements in INPUT_SECTIONS.
2742 Output_section::build_relaxation_map(
2743 const Input_section_list
& input_sections
,
2745 Relaxation_map
* relaxation_map
) const
2747 for (size_t i
= 0; i
< limit
; ++i
)
2749 const Input_section
& is(input_sections
[i
]);
2750 if (is
.is_input_section() || is
.is_relaxed_input_section())
2752 Section_id
sid(is
.relobj(), is
.shndx());
2753 (*relaxation_map
)[sid
] = i
;
2758 // Convert regular input sections in INPUT_SECTIONS into relaxed input
2759 // sections in RELAXED_SECTIONS. MAP is a prebuilt map from section id
2760 // indices of INPUT_SECTIONS.
2763 Output_section::convert_input_sections_in_list_to_relaxed_sections(
2764 const std::vector
<Output_relaxed_input_section
*>& relaxed_sections
,
2765 const Relaxation_map
& map
,
2766 Input_section_list
* input_sections
)
2768 for (size_t i
= 0; i
< relaxed_sections
.size(); ++i
)
2770 Output_relaxed_input_section
* poris
= relaxed_sections
[i
];
2771 Section_id
sid(poris
->relobj(), poris
->shndx());
2772 Relaxation_map::const_iterator p
= map
.find(sid
);
2773 gold_assert(p
!= map
.end());
2774 gold_assert((*input_sections
)[p
->second
].is_input_section());
2776 // Remember section order index of original input section
2777 // if it is set. Copy it to the relaxed input section.
2779 (*input_sections
)[p
->second
].section_order_index();
2780 (*input_sections
)[p
->second
] = Input_section(poris
);
2781 (*input_sections
)[p
->second
].set_section_order_index(soi
);
2785 // Convert regular input sections into relaxed input sections. RELAXED_SECTIONS
2786 // is a vector of pointers to Output_relaxed_input_section or its derived
2787 // classes. The relaxed sections must correspond to existing input sections.
2790 Output_section::convert_input_sections_to_relaxed_sections(
2791 const std::vector
<Output_relaxed_input_section
*>& relaxed_sections
)
2793 gold_assert(parameters
->target().may_relax());
2795 // We want to make sure that restore_states does not undo the effect of
2796 // this. If there is no checkpoint active, just search the current
2797 // input section list and replace the sections there. If there is
2798 // a checkpoint, also replace the sections there.
2800 // By default, we look at the whole list.
2801 size_t limit
= this->input_sections_
.size();
2803 if (this->checkpoint_
!= NULL
)
2805 // Replace input sections with relaxed input section in the saved
2806 // copy of the input section list.
2807 if (this->checkpoint_
->input_sections_saved())
2810 this->build_relaxation_map(
2811 *(this->checkpoint_
->input_sections()),
2812 this->checkpoint_
->input_sections()->size(),
2814 this->convert_input_sections_in_list_to_relaxed_sections(
2817 this->checkpoint_
->input_sections());
2821 // We have not copied the input section list yet. Instead, just
2822 // look at the portion that would be saved.
2823 limit
= this->checkpoint_
->input_sections_size();
2827 // Convert input sections in input_section_list.
2829 this->build_relaxation_map(this->input_sections_
, limit
, &map
);
2830 this->convert_input_sections_in_list_to_relaxed_sections(
2833 &this->input_sections_
);
2835 // Update fast look-up map.
2836 if (this->lookup_maps_
->is_valid())
2837 for (size_t i
= 0; i
< relaxed_sections
.size(); ++i
)
2839 Output_relaxed_input_section
* poris
= relaxed_sections
[i
];
2840 this->lookup_maps_
->add_relaxed_input_section(poris
->relobj(),
2841 poris
->shndx(), poris
);
2845 // Update the output section flags based on input section flags.
2848 Output_section::update_flags_for_input_section(elfcpp::Elf_Xword flags
)
2850 // If we created the section with SHF_ALLOC clear, we set the
2851 // address. If we are now setting the SHF_ALLOC flag, we need to
2853 if ((this->flags_
& elfcpp::SHF_ALLOC
) == 0
2854 && (flags
& elfcpp::SHF_ALLOC
) != 0)
2855 this->mark_address_invalid();
2857 this->flags_
|= (flags
2858 & (elfcpp::SHF_WRITE
2860 | elfcpp::SHF_EXECINSTR
));
2862 if ((flags
& elfcpp::SHF_MERGE
) == 0)
2863 this->flags_
&=~ elfcpp::SHF_MERGE
;
2866 if (this->current_data_size_for_child() == 0)
2867 this->flags_
|= elfcpp::SHF_MERGE
;
2870 if ((flags
& elfcpp::SHF_STRINGS
) == 0)
2871 this->flags_
&=~ elfcpp::SHF_STRINGS
;
2874 if (this->current_data_size_for_child() == 0)
2875 this->flags_
|= elfcpp::SHF_STRINGS
;
2879 // Find the merge section into which an input section with index SHNDX in
2880 // OBJECT has been added. Return NULL if none found.
2882 Output_section_data
*
2883 Output_section::find_merge_section(const Relobj
* object
,
2884 unsigned int shndx
) const
2886 if (!this->lookup_maps_
->is_valid())
2887 this->build_lookup_maps();
2888 return this->lookup_maps_
->find_merge_section(object
, shndx
);
2891 // Build the lookup maps for merge and relaxed sections. This is needs
2892 // to be declared as a const methods so that it is callable with a const
2893 // Output_section pointer. The method only updates states of the maps.
2896 Output_section::build_lookup_maps() const
2898 this->lookup_maps_
->clear();
2899 for (Input_section_list::const_iterator p
= this->input_sections_
.begin();
2900 p
!= this->input_sections_
.end();
2903 if (p
->is_merge_section())
2905 Output_merge_base
* pomb
= p
->output_merge_base();
2906 Merge_section_properties
msp(pomb
->is_string(), pomb
->entsize(),
2908 this->lookup_maps_
->add_merge_section(msp
, pomb
);
2909 for (Output_merge_base::Input_sections::const_iterator is
=
2910 pomb
->input_sections_begin();
2911 is
!= pomb
->input_sections_end();
2914 const Const_section_id
& csid
= *is
;
2915 this->lookup_maps_
->add_merge_input_section(csid
.first
,
2920 else if (p
->is_relaxed_input_section())
2922 Output_relaxed_input_section
* poris
= p
->relaxed_input_section();
2923 this->lookup_maps_
->add_relaxed_input_section(poris
->relobj(),
2924 poris
->shndx(), poris
);
2929 // Find an relaxed input section corresponding to an input section
2930 // in OBJECT with index SHNDX.
2932 const Output_relaxed_input_section
*
2933 Output_section::find_relaxed_input_section(const Relobj
* object
,
2934 unsigned int shndx
) const
2936 if (!this->lookup_maps_
->is_valid())
2937 this->build_lookup_maps();
2938 return this->lookup_maps_
->find_relaxed_input_section(object
, shndx
);
2941 // Given an address OFFSET relative to the start of input section
2942 // SHNDX in OBJECT, return whether this address is being included in
2943 // the final link. This should only be called if SHNDX in OBJECT has
2944 // a special mapping.
2947 Output_section::is_input_address_mapped(const Relobj
* object
,
2951 // Look at the Output_section_data_maps first.
2952 const Output_section_data
* posd
= this->find_merge_section(object
, shndx
);
2954 posd
= this->find_relaxed_input_section(object
, shndx
);
2958 section_offset_type output_offset
;
2959 bool found
= posd
->output_offset(object
, shndx
, offset
, &output_offset
);
2961 return output_offset
!= -1;
2964 // Fall back to the slow look-up.
2965 for (Input_section_list::const_iterator p
= this->input_sections_
.begin();
2966 p
!= this->input_sections_
.end();
2969 section_offset_type output_offset
;
2970 if (p
->output_offset(object
, shndx
, offset
, &output_offset
))
2971 return output_offset
!= -1;
2974 // By default we assume that the address is mapped. This should
2975 // only be called after we have passed all sections to Layout. At
2976 // that point we should know what we are discarding.
2980 // Given an address OFFSET relative to the start of input section
2981 // SHNDX in object OBJECT, return the output offset relative to the
2982 // start of the input section in the output section. This should only
2983 // be called if SHNDX in OBJECT has a special mapping.
2986 Output_section::output_offset(const Relobj
* object
, unsigned int shndx
,
2987 section_offset_type offset
) const
2989 // This can only be called meaningfully when we know the data size
2991 gold_assert(this->is_data_size_valid());
2993 // Look at the Output_section_data_maps first.
2994 const Output_section_data
* posd
= this->find_merge_section(object
, shndx
);
2996 posd
= this->find_relaxed_input_section(object
, shndx
);
2999 section_offset_type output_offset
;
3000 bool found
= posd
->output_offset(object
, shndx
, offset
, &output_offset
);
3002 return output_offset
;
3005 // Fall back to the slow look-up.
3006 for (Input_section_list::const_iterator p
= this->input_sections_
.begin();
3007 p
!= this->input_sections_
.end();
3010 section_offset_type output_offset
;
3011 if (p
->output_offset(object
, shndx
, offset
, &output_offset
))
3012 return output_offset
;
3017 // Return the output virtual address of OFFSET relative to the start
3018 // of input section SHNDX in object OBJECT.
3021 Output_section::output_address(const Relobj
* object
, unsigned int shndx
,
3024 uint64_t addr
= this->address() + this->first_input_offset_
;
3026 // Look at the Output_section_data_maps first.
3027 const Output_section_data
* posd
= this->find_merge_section(object
, shndx
);
3029 posd
= this->find_relaxed_input_section(object
, shndx
);
3030 if (posd
!= NULL
&& posd
->is_address_valid())
3032 section_offset_type output_offset
;
3033 bool found
= posd
->output_offset(object
, shndx
, offset
, &output_offset
);
3035 return posd
->address() + output_offset
;
3038 // Fall back to the slow look-up.
3039 for (Input_section_list::const_iterator p
= this->input_sections_
.begin();
3040 p
!= this->input_sections_
.end();
3043 addr
= align_address(addr
, p
->addralign());
3044 section_offset_type output_offset
;
3045 if (p
->output_offset(object
, shndx
, offset
, &output_offset
))
3047 if (output_offset
== -1)
3049 return addr
+ output_offset
;
3051 addr
+= p
->data_size();
3054 // If we get here, it means that we don't know the mapping for this
3055 // input section. This might happen in principle if
3056 // add_input_section were called before add_output_section_data.
3057 // But it should never actually happen.
3062 // Find the output address of the start of the merged section for
3063 // input section SHNDX in object OBJECT.
3066 Output_section::find_starting_output_address(const Relobj
* object
,
3068 uint64_t* paddr
) const
3070 // FIXME: This becomes a bottle-neck if we have many relaxed sections.
3071 // Looking up the merge section map does not always work as we sometimes
3072 // find a merge section without its address set.
3073 uint64_t addr
= this->address() + this->first_input_offset_
;
3074 for (Input_section_list::const_iterator p
= this->input_sections_
.begin();
3075 p
!= this->input_sections_
.end();
3078 addr
= align_address(addr
, p
->addralign());
3080 // It would be nice if we could use the existing output_offset
3081 // method to get the output offset of input offset 0.
3082 // Unfortunately we don't know for sure that input offset 0 is
3084 if (p
->is_merge_section_for(object
, shndx
))
3090 addr
+= p
->data_size();
3093 // We couldn't find a merge output section for this input section.
3097 // Update the data size of an Output_section.
3100 Output_section::update_data_size()
3102 if (this->input_sections_
.empty())
3105 if (this->must_sort_attached_input_sections()
3106 || this->input_section_order_specified())
3107 this->sort_attached_input_sections();
3109 off_t off
= this->first_input_offset_
;
3110 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3111 p
!= this->input_sections_
.end();
3114 off
= align_address(off
, p
->addralign());
3115 off
+= p
->current_data_size();
3118 this->set_current_data_size_for_child(off
);
3121 // Set the data size of an Output_section. This is where we handle
3122 // setting the addresses of any Output_section_data objects.
3125 Output_section::set_final_data_size()
3129 if (this->input_sections_
.empty())
3130 data_size
= this->current_data_size_for_child();
3133 if (this->must_sort_attached_input_sections()
3134 || this->input_section_order_specified())
3135 this->sort_attached_input_sections();
3137 uint64_t address
= this->address();
3138 off_t startoff
= this->offset();
3139 off_t off
= startoff
+ this->first_input_offset_
;
3140 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3141 p
!= this->input_sections_
.end();
3144 off
= align_address(off
, p
->addralign());
3145 p
->set_address_and_file_offset(address
+ (off
- startoff
), off
,
3147 off
+= p
->data_size();
3149 data_size
= off
- startoff
;
3152 // For full incremental links, we want to allocate some patch space
3153 // in most sections for subsequent incremental updates.
3154 if (this->is_patch_space_allowed_
&& parameters
->incremental_full())
3156 double pct
= parameters
->options().incremental_patch();
3157 size_t extra
= static_cast<size_t>(data_size
* pct
);
3158 if (this->free_space_fill_
!= NULL
3159 && this->free_space_fill_
->minimum_hole_size() > extra
)
3160 extra
= this->free_space_fill_
->minimum_hole_size();
3161 off_t new_size
= align_address(data_size
+ extra
, this->addralign());
3162 this->patch_space_
= new_size
- data_size
;
3163 gold_debug(DEBUG_INCREMENTAL
,
3164 "set_final_data_size: %08lx + %08lx: section %s",
3165 static_cast<long>(data_size
),
3166 static_cast<long>(this->patch_space_
),
3168 data_size
= new_size
;
3171 this->set_data_size(data_size
);
3174 // Reset the address and file offset.
3177 Output_section::do_reset_address_and_file_offset()
3179 // An unallocated section has no address. Forcing this means that
3180 // we don't need special treatment for symbols defined in debug
3181 // sections. We do the same in the constructor. This does not
3182 // apply to NOLOAD sections though.
3183 if (((this->flags_
& elfcpp::SHF_ALLOC
) == 0) && !this->is_noload_
)
3184 this->set_address(0);
3186 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3187 p
!= this->input_sections_
.end();
3189 p
->reset_address_and_file_offset();
3191 // Remove any patch space that was added in set_final_data_size.
3192 if (this->patch_space_
> 0)
3194 this->set_current_data_size_for_child(this->current_data_size_for_child()
3195 - this->patch_space_
);
3196 this->patch_space_
= 0;
3200 // Return true if address and file offset have the values after reset.
3203 Output_section::do_address_and_file_offset_have_reset_values() const
3205 if (this->is_offset_valid())
3208 // An unallocated section has address 0 after its construction or a reset.
3209 if ((this->flags_
& elfcpp::SHF_ALLOC
) == 0)
3210 return this->is_address_valid() && this->address() == 0;
3212 return !this->is_address_valid();
3215 // Set the TLS offset. Called only for SHT_TLS sections.
3218 Output_section::do_set_tls_offset(uint64_t tls_base
)
3220 this->tls_offset_
= this->address() - tls_base
;
3223 // In a few cases we need to sort the input sections attached to an
3224 // output section. This is used to implement the type of constructor
3225 // priority ordering implemented by the GNU linker, in which the
3226 // priority becomes part of the section name and the sections are
3227 // sorted by name. We only do this for an output section if we see an
3228 // attached input section matching ".ctors.*", ".dtors.*",
3229 // ".init_array.*" or ".fini_array.*".
3231 class Output_section::Input_section_sort_entry
3234 Input_section_sort_entry()
3235 : input_section_(), index_(-1U), section_has_name_(false),
3239 Input_section_sort_entry(const Input_section
& input_section
,
3241 bool must_sort_attached_input_sections
)
3242 : input_section_(input_section
), index_(index
),
3243 section_has_name_(input_section
.is_input_section()
3244 || input_section
.is_relaxed_input_section())
3246 if (this->section_has_name_
3247 && must_sort_attached_input_sections
)
3249 // This is only called single-threaded from Layout::finalize,
3250 // so it is OK to lock. Unfortunately we have no way to pass
3252 const Task
* dummy_task
= reinterpret_cast<const Task
*>(-1);
3253 Object
* obj
= (input_section
.is_input_section()
3254 ? input_section
.relobj()
3255 : input_section
.relaxed_input_section()->relobj());
3256 Task_lock_obj
<Object
> tl(dummy_task
, obj
);
3258 // This is a slow operation, which should be cached in
3259 // Layout::layout if this becomes a speed problem.
3260 this->section_name_
= obj
->section_name(input_section
.shndx());
3264 // Return the Input_section.
3265 const Input_section
&
3266 input_section() const
3268 gold_assert(this->index_
!= -1U);
3269 return this->input_section_
;
3272 // The index of this entry in the original list. This is used to
3273 // make the sort stable.
3277 gold_assert(this->index_
!= -1U);
3278 return this->index_
;
3281 // Whether there is a section name.
3283 section_has_name() const
3284 { return this->section_has_name_
; }
3286 // The section name.
3288 section_name() const
3290 gold_assert(this->section_has_name_
);
3291 return this->section_name_
;
3294 // Return true if the section name has a priority. This is assumed
3295 // to be true if it has a dot after the initial dot.
3297 has_priority() const
3299 gold_assert(this->section_has_name_
);
3300 return this->section_name_
.find('.', 1) != std::string::npos
;
3303 // Return the priority. Believe it or not, gcc encodes the priority
3304 // differently for .ctors/.dtors and .init_array/.fini_array
3307 get_priority() const
3309 gold_assert(this->section_has_name_
);
3311 if (is_prefix_of(".ctors.", this->section_name_
.c_str())
3312 || is_prefix_of(".dtors.", this->section_name_
.c_str()))
3314 else if (is_prefix_of(".init_array.", this->section_name_
.c_str())
3315 || is_prefix_of(".fini_array.", this->section_name_
.c_str()))
3320 unsigned long prio
= strtoul((this->section_name_
.c_str()
3321 + (is_ctors
? 7 : 12)),
3326 return 65535 - prio
;
3331 // Return true if this an input file whose base name matches
3332 // FILE_NAME. The base name must have an extension of ".o", and
3333 // must be exactly FILE_NAME.o or FILE_NAME, one character, ".o".
3334 // This is to match crtbegin.o as well as crtbeginS.o without
3335 // getting confused by other possibilities. Overall matching the
3336 // file name this way is a dreadful hack, but the GNU linker does it
3337 // in order to better support gcc, and we need to be compatible.
3339 match_file_name(const char* file_name
) const
3340 { return Layout::match_file_name(this->input_section_
.relobj(), file_name
); }
3342 // Returns 1 if THIS should appear before S in section order, -1 if S
3343 // appears before THIS and 0 if they are not comparable.
3345 compare_section_ordering(const Input_section_sort_entry
& s
) const
3347 unsigned int this_secn_index
= this->input_section_
.section_order_index();
3348 unsigned int s_secn_index
= s
.input_section().section_order_index();
3349 if (this_secn_index
> 0 && s_secn_index
> 0)
3351 if (this_secn_index
< s_secn_index
)
3353 else if (this_secn_index
> s_secn_index
)
3360 // The Input_section we are sorting.
3361 Input_section input_section_
;
3362 // The index of this Input_section in the original list.
3363 unsigned int index_
;
3364 // Whether this Input_section has a section name--it won't if this
3365 // is some random Output_section_data.
3366 bool section_has_name_
;
3367 // The section name if there is one.
3368 std::string section_name_
;
3371 // Return true if S1 should come before S2 in the output section.
3374 Output_section::Input_section_sort_compare::operator()(
3375 const Output_section::Input_section_sort_entry
& s1
,
3376 const Output_section::Input_section_sort_entry
& s2
) const
3378 // crtbegin.o must come first.
3379 bool s1_begin
= s1
.match_file_name("crtbegin");
3380 bool s2_begin
= s2
.match_file_name("crtbegin");
3381 if (s1_begin
|| s2_begin
)
3387 return s1
.index() < s2
.index();
3390 // crtend.o must come last.
3391 bool s1_end
= s1
.match_file_name("crtend");
3392 bool s2_end
= s2
.match_file_name("crtend");
3393 if (s1_end
|| s2_end
)
3399 return s1
.index() < s2
.index();
3402 // We sort all the sections with no names to the end.
3403 if (!s1
.section_has_name() || !s2
.section_has_name())
3405 if (s1
.section_has_name())
3407 if (s2
.section_has_name())
3409 return s1
.index() < s2
.index();
3412 // A section with a priority follows a section without a priority.
3413 bool s1_has_priority
= s1
.has_priority();
3414 bool s2_has_priority
= s2
.has_priority();
3415 if (s1_has_priority
&& !s2_has_priority
)
3417 if (!s1_has_priority
&& s2_has_priority
)
3420 // Check if a section order exists for these sections through a section
3421 // ordering file. If sequence_num is 0, an order does not exist.
3422 int sequence_num
= s1
.compare_section_ordering(s2
);
3423 if (sequence_num
!= 0)
3424 return sequence_num
== 1;
3426 // Otherwise we sort by name.
3427 int compare
= s1
.section_name().compare(s2
.section_name());
3431 // Otherwise we keep the input order.
3432 return s1
.index() < s2
.index();
3435 // Return true if S1 should come before S2 in an .init_array or .fini_array
3439 Output_section::Input_section_sort_init_fini_compare::operator()(
3440 const Output_section::Input_section_sort_entry
& s1
,
3441 const Output_section::Input_section_sort_entry
& s2
) const
3443 // We sort all the sections with no names to the end.
3444 if (!s1
.section_has_name() || !s2
.section_has_name())
3446 if (s1
.section_has_name())
3448 if (s2
.section_has_name())
3450 return s1
.index() < s2
.index();
3453 // A section without a priority follows a section with a priority.
3454 // This is the reverse of .ctors and .dtors sections.
3455 bool s1_has_priority
= s1
.has_priority();
3456 bool s2_has_priority
= s2
.has_priority();
3457 if (s1_has_priority
&& !s2_has_priority
)
3459 if (!s1_has_priority
&& s2_has_priority
)
3462 // .ctors and .dtors sections without priority come after
3463 // .init_array and .fini_array sections without priority.
3464 if (!s1_has_priority
3465 && (s1
.section_name() == ".ctors" || s1
.section_name() == ".dtors")
3466 && s1
.section_name() != s2
.section_name())
3468 if (!s2_has_priority
3469 && (s2
.section_name() == ".ctors" || s2
.section_name() == ".dtors")
3470 && s2
.section_name() != s1
.section_name())
3473 // Sort by priority if we can.
3474 if (s1_has_priority
)
3476 unsigned int s1_prio
= s1
.get_priority();
3477 unsigned int s2_prio
= s2
.get_priority();
3478 if (s1_prio
< s2_prio
)
3480 else if (s1_prio
> s2_prio
)
3484 // Check if a section order exists for these sections through a section
3485 // ordering file. If sequence_num is 0, an order does not exist.
3486 int sequence_num
= s1
.compare_section_ordering(s2
);
3487 if (sequence_num
!= 0)
3488 return sequence_num
== 1;
3490 // Otherwise we sort by name.
3491 int compare
= s1
.section_name().compare(s2
.section_name());
3495 // Otherwise we keep the input order.
3496 return s1
.index() < s2
.index();
3499 // Return true if S1 should come before S2. Sections that do not match
3500 // any pattern in the section ordering file are placed ahead of the sections
3501 // that match some pattern. This function is also used to group text according
3502 // to their prefix. The following prefixes are recognized: ".text.startup",
3503 // ".text.hot", and ".text.unlikely".
3506 Output_section::Input_section_sort_section_order_index_compare::operator()(
3507 const Output_section::Input_section_sort_entry
& s1
,
3508 const Output_section::Input_section_sort_entry
& s2
) const
3510 unsigned int s1_secn_index
= s1
.input_section().section_order_index();
3511 unsigned int s2_secn_index
= s2
.input_section().section_order_index();
3513 // If section ordering is specified, it takes precedence.
3514 if (s1_secn_index
!= s2_secn_index
)
3515 return s1_secn_index
< s2_secn_index
;
3517 // Sort all the sections with no names to the end.
3518 if (!s1
.section_has_name() || !s2
.section_has_name())
3520 if (s1
.section_has_name())
3522 if (s2
.section_has_name())
3524 return s1
.index() < s2
.index();
3527 // If it is a text section use the following order:
3528 // .text.unlikely, .text.startup, .text.hot. The prefixes
3529 // must match those in function is_section_name_prefix_grouped
3531 const char* section_prefix
[] =
3538 const unsigned int num_prefixes
3539 = sizeof(section_prefix
) / sizeof(const char*);
3541 unsigned int s1_group_index
= num_prefixes
;
3542 unsigned int s2_group_index
= num_prefixes
;
3544 unsigned int flag_done
= 0;
3545 for (unsigned int i
= 0; i
< num_prefixes
&& flag_done
< 2; i
++)
3547 if (s1_group_index
== num_prefixes
3548 && is_prefix_of(section_prefix
[i
], s1
.section_name().c_str()))
3554 if (s2_group_index
== num_prefixes
3555 && is_prefix_of(section_prefix
[i
], s2
.section_name().c_str()))
3562 if (s1_group_index
== s2_group_index
)
3563 return s1
.index() < s2
.index();
3565 return s1_group_index
< s2_group_index
;
3568 // This updates the section order index of input sections according to the
3569 // the order specified in the mapping from Section id to order index.
3572 Output_section::update_section_layout(
3573 const Section_layout_order
* order_map
)
3575 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3576 p
!= this->input_sections_
.end();
3579 if (p
->is_input_section()
3580 || p
->is_relaxed_input_section())
3582 Object
* obj
= (p
->is_input_section()
3584 : p
->relaxed_input_section()->relobj());
3585 unsigned int shndx
= p
->shndx();
3586 Section_layout_order::const_iterator it
3587 = order_map
->find(Section_id(obj
, shndx
));
3588 if (it
== order_map
->end())
3590 unsigned int section_order_index
= it
->second
;
3591 if (section_order_index
!= 0)
3593 p
->set_section_order_index(section_order_index
);
3594 this->set_input_section_order_specified();
3600 // Sort the input sections attached to an output section.
3603 Output_section::sort_attached_input_sections()
3605 if (this->attached_input_sections_are_sorted_
)
3608 if (this->checkpoint_
!= NULL
3609 && !this->checkpoint_
->input_sections_saved())
3610 this->checkpoint_
->save_input_sections();
3612 // The only thing we know about an input section is the object and
3613 // the section index. We need the section name. Recomputing this
3614 // is slow but this is an unusual case. If this becomes a speed
3615 // problem we can cache the names as required in Layout::layout.
3617 // We start by building a larger vector holding a copy of each
3618 // Input_section, plus its current index in the list and its name.
3619 std::vector
<Input_section_sort_entry
> sort_list
;
3622 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3623 p
!= this->input_sections_
.end();
3625 sort_list
.push_back(Input_section_sort_entry(*p
, i
,
3626 (this->must_sort_attached_input_sections()
3627 || this->input_section_order_specified())));
3629 // Sort the input sections.
3630 if (this->must_sort_attached_input_sections())
3632 if (this->type() == elfcpp::SHT_PREINIT_ARRAY
3633 || this->type() == elfcpp::SHT_INIT_ARRAY
3634 || this->type() == elfcpp::SHT_FINI_ARRAY
)
3635 std::sort(sort_list
.begin(), sort_list
.end(),
3636 Input_section_sort_init_fini_compare());
3638 std::sort(sort_list
.begin(), sort_list
.end(),
3639 Input_section_sort_compare());
3643 gold_assert(this->input_section_order_specified());
3644 std::sort(sort_list
.begin(), sort_list
.end(),
3645 Input_section_sort_section_order_index_compare());
3648 // Copy the sorted input sections back to our list.
3649 this->input_sections_
.clear();
3650 for (std::vector
<Input_section_sort_entry
>::iterator p
= sort_list
.begin();
3651 p
!= sort_list
.end();
3653 this->input_sections_
.push_back(p
->input_section());
3656 // Remember that we sorted the input sections, since we might get
3658 this->attached_input_sections_are_sorted_
= true;
3661 // Write the section header to *OSHDR.
3663 template<int size
, bool big_endian
>
3665 Output_section::write_header(const Layout
* layout
,
3666 const Stringpool
* secnamepool
,
3667 elfcpp::Shdr_write
<size
, big_endian
>* oshdr
) const
3669 oshdr
->put_sh_name(secnamepool
->get_offset(this->name_
));
3670 oshdr
->put_sh_type(this->type_
);
3672 elfcpp::Elf_Xword flags
= this->flags_
;
3673 if (this->info_section_
!= NULL
&& this->info_uses_section_index_
)
3674 flags
|= elfcpp::SHF_INFO_LINK
;
3675 oshdr
->put_sh_flags(flags
);
3677 oshdr
->put_sh_addr(this->address());
3678 oshdr
->put_sh_offset(this->offset());
3679 oshdr
->put_sh_size(this->data_size());
3680 if (this->link_section_
!= NULL
)
3681 oshdr
->put_sh_link(this->link_section_
->out_shndx());
3682 else if (this->should_link_to_symtab_
)
3683 oshdr
->put_sh_link(layout
->symtab_section_shndx());
3684 else if (this->should_link_to_dynsym_
)
3685 oshdr
->put_sh_link(layout
->dynsym_section()->out_shndx());
3687 oshdr
->put_sh_link(this->link_
);
3689 elfcpp::Elf_Word info
;
3690 if (this->info_section_
!= NULL
)
3692 if (this->info_uses_section_index_
)
3693 info
= this->info_section_
->out_shndx();
3695 info
= this->info_section_
->symtab_index();
3697 else if (this->info_symndx_
!= NULL
)
3698 info
= this->info_symndx_
->symtab_index();
3701 oshdr
->put_sh_info(info
);
3703 oshdr
->put_sh_addralign(this->addralign_
);
3704 oshdr
->put_sh_entsize(this->entsize_
);
3707 // Write out the data. For input sections the data is written out by
3708 // Object::relocate, but we have to handle Output_section_data objects
3712 Output_section::do_write(Output_file
* of
)
3714 gold_assert(!this->requires_postprocessing());
3716 // If the target performs relaxation, we delay filler generation until now.
3717 gold_assert(!this->generate_code_fills_at_write_
|| this->fills_
.empty());
3719 off_t output_section_file_offset
= this->offset();
3720 for (Fill_list::iterator p
= this->fills_
.begin();
3721 p
!= this->fills_
.end();
3724 std::string
fill_data(parameters
->target().code_fill(p
->length()));
3725 of
->write(output_section_file_offset
+ p
->section_offset(),
3726 fill_data
.data(), fill_data
.size());
3729 off_t off
= this->offset() + this->first_input_offset_
;
3730 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3731 p
!= this->input_sections_
.end();
3734 off_t aligned_off
= align_address(off
, p
->addralign());
3735 if (this->generate_code_fills_at_write_
&& (off
!= aligned_off
))
3737 size_t fill_len
= aligned_off
- off
;
3738 std::string
fill_data(parameters
->target().code_fill(fill_len
));
3739 of
->write(off
, fill_data
.data(), fill_data
.size());
3743 off
= aligned_off
+ p
->data_size();
3746 // For incremental links, fill in unused chunks in debug sections
3747 // with dummy compilation unit headers.
3748 if (this->free_space_fill_
!= NULL
)
3750 for (Free_list::Const_iterator p
= this->free_list_
.begin();
3751 p
!= this->free_list_
.end();
3754 off_t off
= p
->start_
;
3755 size_t len
= p
->end_
- off
;
3756 this->free_space_fill_
->write(of
, this->offset() + off
, len
);
3758 if (this->patch_space_
> 0)
3760 off_t off
= this->current_data_size_for_child() - this->patch_space_
;
3761 this->free_space_fill_
->write(of
, this->offset() + off
,
3762 this->patch_space_
);
3767 // If a section requires postprocessing, create the buffer to use.
3770 Output_section::create_postprocessing_buffer()
3772 gold_assert(this->requires_postprocessing());
3774 if (this->postprocessing_buffer_
!= NULL
)
3777 if (!this->input_sections_
.empty())
3779 off_t off
= this->first_input_offset_
;
3780 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3781 p
!= this->input_sections_
.end();
3784 off
= align_address(off
, p
->addralign());
3785 p
->finalize_data_size();
3786 off
+= p
->data_size();
3788 this->set_current_data_size_for_child(off
);
3791 off_t buffer_size
= this->current_data_size_for_child();
3792 this->postprocessing_buffer_
= new unsigned char[buffer_size
];
3795 // Write all the data of an Output_section into the postprocessing
3796 // buffer. This is used for sections which require postprocessing,
3797 // such as compression. Input sections are handled by
3798 // Object::Relocate.
3801 Output_section::write_to_postprocessing_buffer()
3803 gold_assert(this->requires_postprocessing());
3805 // If the target performs relaxation, we delay filler generation until now.
3806 gold_assert(!this->generate_code_fills_at_write_
|| this->fills_
.empty());
3808 unsigned char* buffer
= this->postprocessing_buffer();
3809 for (Fill_list::iterator p
= this->fills_
.begin();
3810 p
!= this->fills_
.end();
3813 std::string
fill_data(parameters
->target().code_fill(p
->length()));
3814 memcpy(buffer
+ p
->section_offset(), fill_data
.data(),
3818 off_t off
= this->first_input_offset_
;
3819 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3820 p
!= this->input_sections_
.end();
3823 off_t aligned_off
= align_address(off
, p
->addralign());
3824 if (this->generate_code_fills_at_write_
&& (off
!= aligned_off
))
3826 size_t fill_len
= aligned_off
- off
;
3827 std::string
fill_data(parameters
->target().code_fill(fill_len
));
3828 memcpy(buffer
+ off
, fill_data
.data(), fill_data
.size());
3831 p
->write_to_buffer(buffer
+ aligned_off
);
3832 off
= aligned_off
+ p
->data_size();
3836 // Get the input sections for linker script processing. We leave
3837 // behind the Output_section_data entries. Note that this may be
3838 // slightly incorrect for merge sections. We will leave them behind,
3839 // but it is possible that the script says that they should follow
3840 // some other input sections, as in:
3841 // .rodata { *(.rodata) *(.rodata.cst*) }
3842 // For that matter, we don't handle this correctly:
3843 // .rodata { foo.o(.rodata.cst*) *(.rodata.cst*) }
3844 // With luck this will never matter.
3847 Output_section::get_input_sections(
3849 const std::string
& fill
,
3850 std::list
<Input_section
>* input_sections
)
3852 if (this->checkpoint_
!= NULL
3853 && !this->checkpoint_
->input_sections_saved())
3854 this->checkpoint_
->save_input_sections();
3856 // Invalidate fast look-up maps.
3857 this->lookup_maps_
->invalidate();
3859 uint64_t orig_address
= address
;
3861 address
= align_address(address
, this->addralign());
3863 Input_section_list remaining
;
3864 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3865 p
!= this->input_sections_
.end();
3868 if (p
->is_input_section()
3869 || p
->is_relaxed_input_section()
3870 || p
->is_merge_section())
3871 input_sections
->push_back(*p
);
3874 uint64_t aligned_address
= align_address(address
, p
->addralign());
3875 if (aligned_address
!= address
&& !fill
.empty())
3877 section_size_type length
=
3878 convert_to_section_size_type(aligned_address
- address
);
3879 std::string this_fill
;
3880 this_fill
.reserve(length
);
3881 while (this_fill
.length() + fill
.length() <= length
)
3883 if (this_fill
.length() < length
)
3884 this_fill
.append(fill
, 0, length
- this_fill
.length());
3886 Output_section_data
* posd
= new Output_data_const(this_fill
, 0);
3887 remaining
.push_back(Input_section(posd
));
3889 address
= aligned_address
;
3891 remaining
.push_back(*p
);
3893 p
->finalize_data_size();
3894 address
+= p
->data_size();
3898 this->input_sections_
.swap(remaining
);
3899 this->first_input_offset_
= 0;
3901 uint64_t data_size
= address
- orig_address
;
3902 this->set_current_data_size_for_child(data_size
);
3906 // Add a script input section. SIS is an Output_section::Input_section,
3907 // which can be either a plain input section or a special input section like
3908 // a relaxed input section. For a special input section, its size must be
3912 Output_section::add_script_input_section(const Input_section
& sis
)
3914 uint64_t data_size
= sis
.data_size();
3915 uint64_t addralign
= sis
.addralign();
3916 if (addralign
> this->addralign_
)
3917 this->addralign_
= addralign
;
3919 off_t offset_in_section
= this->current_data_size_for_child();
3920 off_t aligned_offset_in_section
= align_address(offset_in_section
,
3923 this->set_current_data_size_for_child(aligned_offset_in_section
3926 this->input_sections_
.push_back(sis
);
3928 // Update fast lookup maps if necessary.
3929 if (this->lookup_maps_
->is_valid())
3931 if (sis
.is_merge_section())
3933 Output_merge_base
* pomb
= sis
.output_merge_base();
3934 Merge_section_properties
msp(pomb
->is_string(), pomb
->entsize(),
3936 this->lookup_maps_
->add_merge_section(msp
, pomb
);
3937 for (Output_merge_base::Input_sections::const_iterator p
=
3938 pomb
->input_sections_begin();
3939 p
!= pomb
->input_sections_end();
3941 this->lookup_maps_
->add_merge_input_section(p
->first
, p
->second
,
3944 else if (sis
.is_relaxed_input_section())
3946 Output_relaxed_input_section
* poris
= sis
.relaxed_input_section();
3947 this->lookup_maps_
->add_relaxed_input_section(poris
->relobj(),
3948 poris
->shndx(), poris
);
3953 // Save states for relaxation.
3956 Output_section::save_states()
3958 gold_assert(this->checkpoint_
== NULL
);
3959 Checkpoint_output_section
* checkpoint
=
3960 new Checkpoint_output_section(this->addralign_
, this->flags_
,
3961 this->input_sections_
,
3962 this->first_input_offset_
,
3963 this->attached_input_sections_are_sorted_
);
3964 this->checkpoint_
= checkpoint
;
3965 gold_assert(this->fills_
.empty());
3969 Output_section::discard_states()
3971 gold_assert(this->checkpoint_
!= NULL
);
3972 delete this->checkpoint_
;
3973 this->checkpoint_
= NULL
;
3974 gold_assert(this->fills_
.empty());
3976 // Simply invalidate the fast lookup maps since we do not keep
3978 this->lookup_maps_
->invalidate();
3982 Output_section::restore_states()
3984 gold_assert(this->checkpoint_
!= NULL
);
3985 Checkpoint_output_section
* checkpoint
= this->checkpoint_
;
3987 this->addralign_
= checkpoint
->addralign();
3988 this->flags_
= checkpoint
->flags();
3989 this->first_input_offset_
= checkpoint
->first_input_offset();
3991 if (!checkpoint
->input_sections_saved())
3993 // If we have not copied the input sections, just resize it.
3994 size_t old_size
= checkpoint
->input_sections_size();
3995 gold_assert(this->input_sections_
.size() >= old_size
);
3996 this->input_sections_
.resize(old_size
);
4000 // We need to copy the whole list. This is not efficient for
4001 // extremely large output with hundreads of thousands of input
4002 // objects. We may need to re-think how we should pass sections
4004 this->input_sections_
= *checkpoint
->input_sections();
4007 this->attached_input_sections_are_sorted_
=
4008 checkpoint
->attached_input_sections_are_sorted();
4010 // Simply invalidate the fast lookup maps since we do not keep
4012 this->lookup_maps_
->invalidate();
4015 // Update the section offsets of input sections in this. This is required if
4016 // relaxation causes some input sections to change sizes.
4019 Output_section::adjust_section_offsets()
4021 if (!this->section_offsets_need_adjustment_
)
4025 for (Input_section_list::iterator p
= this->input_sections_
.begin();
4026 p
!= this->input_sections_
.end();
4029 off
= align_address(off
, p
->addralign());
4030 if (p
->is_input_section())
4031 p
->relobj()->set_section_offset(p
->shndx(), off
);
4032 off
+= p
->data_size();
4035 this->section_offsets_need_adjustment_
= false;
4038 // Print to the map file.
4041 Output_section::do_print_to_mapfile(Mapfile
* mapfile
) const
4043 mapfile
->print_output_section(this);
4045 for (Input_section_list::const_iterator p
= this->input_sections_
.begin();
4046 p
!= this->input_sections_
.end();
4048 p
->print_to_mapfile(mapfile
);
4051 // Print stats for merge sections to stderr.
4054 Output_section::print_merge_stats()
4056 Input_section_list::iterator p
;
4057 for (p
= this->input_sections_
.begin();
4058 p
!= this->input_sections_
.end();
4060 p
->print_merge_stats(this->name_
);
4063 // Set a fixed layout for the section. Used for incremental update links.
4066 Output_section::set_fixed_layout(uint64_t sh_addr
, off_t sh_offset
,
4067 off_t sh_size
, uint64_t sh_addralign
)
4069 this->addralign_
= sh_addralign
;
4070 this->set_current_data_size(sh_size
);
4071 if ((this->flags_
& elfcpp::SHF_ALLOC
) != 0)
4072 this->set_address(sh_addr
);
4073 this->set_file_offset(sh_offset
);
4074 this->finalize_data_size();
4075 this->free_list_
.init(sh_size
, false);
4076 this->has_fixed_layout_
= true;
4079 // Reserve space within the fixed layout for the section. Used for
4080 // incremental update links.
4083 Output_section::reserve(uint64_t sh_offset
, uint64_t sh_size
)
4085 this->free_list_
.remove(sh_offset
, sh_offset
+ sh_size
);
4088 // Allocate space from the free list for the section. Used for
4089 // incremental update links.
4092 Output_section::allocate(off_t len
, uint64_t addralign
)
4094 return this->free_list_
.allocate(len
, addralign
, 0);
4097 // Output segment methods.
4099 Output_segment::Output_segment(elfcpp::Elf_Word type
, elfcpp::Elf_Word flags
)
4109 is_max_align_known_(false),
4110 are_addresses_set_(false),
4111 is_large_data_segment_(false),
4112 is_unique_segment_(false)
4114 // The ELF ABI specifies that a PT_TLS segment always has PF_R as
4116 if (type
== elfcpp::PT_TLS
)
4117 this->flags_
= elfcpp::PF_R
;
4120 // Add an Output_section to a PT_LOAD Output_segment.
4123 Output_segment::add_output_section_to_load(Layout
* layout
,
4125 elfcpp::Elf_Word seg_flags
)
4127 gold_assert(this->type() == elfcpp::PT_LOAD
);
4128 gold_assert((os
->flags() & elfcpp::SHF_ALLOC
) != 0);
4129 gold_assert(!this->is_max_align_known_
);
4130 gold_assert(os
->is_large_data_section() == this->is_large_data_segment());
4132 this->update_flags_for_output_section(seg_flags
);
4134 // We don't want to change the ordering if we have a linker script
4135 // with a SECTIONS clause.
4136 Output_section_order order
= os
->order();
4137 if (layout
->script_options()->saw_sections_clause())
4138 order
= static_cast<Output_section_order
>(0);
4140 gold_assert(order
!= ORDER_INVALID
);
4142 this->output_lists_
[order
].push_back(os
);
4145 // Add an Output_section to a non-PT_LOAD Output_segment.
4148 Output_segment::add_output_section_to_nonload(Output_section
* os
,
4149 elfcpp::Elf_Word seg_flags
)
4151 gold_assert(this->type() != elfcpp::PT_LOAD
);
4152 gold_assert((os
->flags() & elfcpp::SHF_ALLOC
) != 0);
4153 gold_assert(!this->is_max_align_known_
);
4155 this->update_flags_for_output_section(seg_flags
);
4157 this->output_lists_
[0].push_back(os
);
4160 // Remove an Output_section from this segment. It is an error if it
4164 Output_segment::remove_output_section(Output_section
* os
)
4166 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4168 Output_data_list
* pdl
= &this->output_lists_
[i
];
4169 for (Output_data_list::iterator p
= pdl
->begin(); p
!= pdl
->end(); ++p
)
4181 // Add an Output_data (which need not be an Output_section) to the
4182 // start of a segment.
4185 Output_segment::add_initial_output_data(Output_data
* od
)
4187 gold_assert(!this->is_max_align_known_
);
4188 Output_data_list::iterator p
= this->output_lists_
[0].begin();
4189 this->output_lists_
[0].insert(p
, od
);
4192 // Return true if this segment has any sections which hold actual
4193 // data, rather than being a BSS section.
4196 Output_segment::has_any_data_sections() const
4198 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4200 const Output_data_list
* pdl
= &this->output_lists_
[i
];
4201 for (Output_data_list::const_iterator p
= pdl
->begin();
4205 if (!(*p
)->is_section())
4207 if ((*p
)->output_section()->type() != elfcpp::SHT_NOBITS
)
4214 // Return whether the first data section (not counting TLS sections)
4215 // is a relro section.
4218 Output_segment::is_first_section_relro() const
4220 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4222 if (i
== static_cast<int>(ORDER_TLS_DATA
)
4223 || i
== static_cast<int>(ORDER_TLS_BSS
))
4225 const Output_data_list
* pdl
= &this->output_lists_
[i
];
4228 Output_data
* p
= pdl
->front();
4229 return p
->is_section() && p
->output_section()->is_relro();
4235 // Return the maximum alignment of the Output_data in Output_segment.
4238 Output_segment::maximum_alignment()
4240 if (!this->is_max_align_known_
)
4242 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4244 const Output_data_list
* pdl
= &this->output_lists_
[i
];
4245 uint64_t addralign
= Output_segment::maximum_alignment_list(pdl
);
4246 if (addralign
> this->max_align_
)
4247 this->max_align_
= addralign
;
4249 this->is_max_align_known_
= true;
4252 return this->max_align_
;
4255 // Return the maximum alignment of a list of Output_data.
4258 Output_segment::maximum_alignment_list(const Output_data_list
* pdl
)
4261 for (Output_data_list::const_iterator p
= pdl
->begin();
4265 uint64_t addralign
= (*p
)->addralign();
4266 if (addralign
> ret
)
4272 // Return whether this segment has any dynamic relocs.
4275 Output_segment::has_dynamic_reloc() const
4277 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4278 if (this->has_dynamic_reloc_list(&this->output_lists_
[i
]))
4283 // Return whether this Output_data_list has any dynamic relocs.
4286 Output_segment::has_dynamic_reloc_list(const Output_data_list
* pdl
) const
4288 for (Output_data_list::const_iterator p
= pdl
->begin();
4291 if ((*p
)->has_dynamic_reloc())
4296 // Set the section addresses for an Output_segment. If RESET is true,
4297 // reset the addresses first. ADDR is the address and *POFF is the
4298 // file offset. Set the section indexes starting with *PSHNDX.
4299 // INCREASE_RELRO is the size of the portion of the first non-relro
4300 // section that should be included in the PT_GNU_RELRO segment.
4301 // If this segment has relro sections, and has been aligned for
4302 // that purpose, set *HAS_RELRO to TRUE. Return the address of
4303 // the immediately following segment. Update *HAS_RELRO, *POFF,
4307 Output_segment::set_section_addresses(Layout
* layout
, bool reset
,
4309 unsigned int* increase_relro
,
4312 unsigned int* pshndx
)
4314 gold_assert(this->type_
== elfcpp::PT_LOAD
);
4316 uint64_t last_relro_pad
= 0;
4317 off_t orig_off
= *poff
;
4319 bool in_tls
= false;
4321 // If we have relro sections, we need to pad forward now so that the
4322 // relro sections plus INCREASE_RELRO end on an abi page boundary.
4323 if (parameters
->options().relro()
4324 && this->is_first_section_relro()
4325 && (!this->are_addresses_set_
|| reset
))
4327 uint64_t relro_size
= 0;
4329 uint64_t max_align
= 0;
4330 for (int i
= 0; i
<= static_cast<int>(ORDER_RELRO_LAST
); ++i
)
4332 Output_data_list
* pdl
= &this->output_lists_
[i
];
4333 Output_data_list::iterator p
;
4334 for (p
= pdl
->begin(); p
!= pdl
->end(); ++p
)
4336 if (!(*p
)->is_section())
4338 uint64_t align
= (*p
)->addralign();
4339 if (align
> max_align
)
4341 if ((*p
)->is_section_flag_set(elfcpp::SHF_TLS
))
4345 // Align the first non-TLS section to the alignment
4346 // of the TLS segment.
4350 relro_size
= align_address(relro_size
, align
);
4351 // Ignore the size of the .tbss section.
4352 if ((*p
)->is_section_flag_set(elfcpp::SHF_TLS
)
4353 && (*p
)->is_section_type(elfcpp::SHT_NOBITS
))
4355 if ((*p
)->is_address_valid())
4356 relro_size
+= (*p
)->data_size();
4359 // FIXME: This could be faster.
4360 (*p
)->set_address_and_file_offset(addr
+ relro_size
,
4362 relro_size
+= (*p
)->data_size();
4363 (*p
)->reset_address_and_file_offset();
4366 if (p
!= pdl
->end())
4369 relro_size
+= *increase_relro
;
4370 // Pad the total relro size to a multiple of the maximum
4371 // section alignment seen.
4372 uint64_t aligned_size
= align_address(relro_size
, max_align
);
4373 // Note the amount of padding added after the last relro section.
4374 last_relro_pad
= aligned_size
- relro_size
;
4377 uint64_t page_align
= parameters
->target().abi_pagesize();
4379 // Align to offset N such that (N + RELRO_SIZE) % PAGE_ALIGN == 0.
4380 uint64_t desired_align
= page_align
- (aligned_size
% page_align
);
4381 if (desired_align
< *poff
% page_align
)
4382 *poff
+= page_align
- *poff
% page_align
;
4383 *poff
+= desired_align
- *poff
% page_align
;
4384 addr
+= *poff
- orig_off
;
4388 if (!reset
&& this->are_addresses_set_
)
4390 gold_assert(this->paddr_
== addr
);
4391 addr
= this->vaddr_
;
4395 this->vaddr_
= addr
;
4396 this->paddr_
= addr
;
4397 this->are_addresses_set_
= true;
4402 this->offset_
= orig_off
;
4406 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4408 if (i
== static_cast<int>(ORDER_RELRO_LAST
))
4410 *poff
+= last_relro_pad
;
4411 addr
+= last_relro_pad
;
4412 if (this->output_lists_
[i
].empty())
4414 // If there is nothing in the ORDER_RELRO_LAST list,
4415 // the padding will occur at the end of the relro
4416 // segment, and we need to add it to *INCREASE_RELRO.
4417 *increase_relro
+= last_relro_pad
;
4420 addr
= this->set_section_list_addresses(layout
, reset
,
4421 &this->output_lists_
[i
],
4422 addr
, poff
, pshndx
, &in_tls
);
4423 if (i
< static_cast<int>(ORDER_SMALL_BSS
))
4425 this->filesz_
= *poff
- orig_off
;
4432 // If the last section was a TLS section, align upward to the
4433 // alignment of the TLS segment, so that the overall size of the TLS
4434 // segment is aligned.
4437 uint64_t segment_align
= layout
->tls_segment()->maximum_alignment();
4438 *poff
= align_address(*poff
, segment_align
);
4441 this->memsz_
= *poff
- orig_off
;
4443 // Ignore the file offset adjustments made by the BSS Output_data
4450 // Set the addresses and file offsets in a list of Output_data
4454 Output_segment::set_section_list_addresses(Layout
* layout
, bool reset
,
4455 Output_data_list
* pdl
,
4456 uint64_t addr
, off_t
* poff
,
4457 unsigned int* pshndx
,
4460 off_t startoff
= *poff
;
4461 // For incremental updates, we may allocate non-fixed sections from
4462 // free space in the file. This keeps track of the high-water mark.
4463 off_t maxoff
= startoff
;
4465 off_t off
= startoff
;
4466 for (Output_data_list::iterator p
= pdl
->begin();
4471 (*p
)->reset_address_and_file_offset();
4473 // When doing an incremental update or when using a linker script,
4474 // the section will most likely already have an address.
4475 if (!(*p
)->is_address_valid())
4477 uint64_t align
= (*p
)->addralign();
4479 if ((*p
)->is_section_flag_set(elfcpp::SHF_TLS
))
4481 // Give the first TLS section the alignment of the
4482 // entire TLS segment. Otherwise the TLS segment as a
4483 // whole may be misaligned.
4486 Output_segment
* tls_segment
= layout
->tls_segment();
4487 gold_assert(tls_segment
!= NULL
);
4488 uint64_t segment_align
= tls_segment
->maximum_alignment();
4489 gold_assert(segment_align
>= align
);
4490 align
= segment_align
;
4497 // If this is the first section after the TLS segment,
4498 // align it to at least the alignment of the TLS
4499 // segment, so that the size of the overall TLS segment
4503 uint64_t segment_align
=
4504 layout
->tls_segment()->maximum_alignment();
4505 if (segment_align
> align
)
4506 align
= segment_align
;
4512 if (!parameters
->incremental_update())
4514 off
= align_address(off
, align
);
4515 (*p
)->set_address_and_file_offset(addr
+ (off
- startoff
), off
);
4519 // Incremental update: allocate file space from free list.
4520 (*p
)->pre_finalize_data_size();
4521 off_t current_size
= (*p
)->current_data_size();
4522 off
= layout
->allocate(current_size
, align
, startoff
);
4525 gold_assert((*p
)->output_section() != NULL
);
4526 gold_fallback(_("out of patch space for section %s; "
4527 "relink with --incremental-full"),
4528 (*p
)->output_section()->name());
4530 (*p
)->set_address_and_file_offset(addr
+ (off
- startoff
), off
);
4531 if ((*p
)->data_size() > current_size
)
4533 gold_assert((*p
)->output_section() != NULL
);
4534 gold_fallback(_("%s: section changed size; "
4535 "relink with --incremental-full"),
4536 (*p
)->output_section()->name());
4540 else if (parameters
->incremental_update())
4542 // For incremental updates, use the fixed offset for the
4543 // high-water mark computation.
4544 off
= (*p
)->offset();
4548 // The script may have inserted a skip forward, but it
4549 // better not have moved backward.
4550 if ((*p
)->address() >= addr
+ (off
- startoff
))
4551 off
+= (*p
)->address() - (addr
+ (off
- startoff
));
4554 if (!layout
->script_options()->saw_sections_clause())
4558 Output_section
* os
= (*p
)->output_section();
4560 // Cast to unsigned long long to avoid format warnings.
4561 unsigned long long previous_dot
=
4562 static_cast<unsigned long long>(addr
+ (off
- startoff
));
4563 unsigned long long dot
=
4564 static_cast<unsigned long long>((*p
)->address());
4567 gold_error(_("dot moves backward in linker script "
4568 "from 0x%llx to 0x%llx"), previous_dot
, dot
);
4570 gold_error(_("address of section '%s' moves backward "
4571 "from 0x%llx to 0x%llx"),
4572 os
->name(), previous_dot
, dot
);
4575 (*p
)->set_file_offset(off
);
4576 (*p
)->finalize_data_size();
4579 if (parameters
->incremental_update())
4580 gold_debug(DEBUG_INCREMENTAL
,
4581 "set_section_list_addresses: %08lx %08lx %s",
4582 static_cast<long>(off
),
4583 static_cast<long>((*p
)->data_size()),
4584 ((*p
)->output_section() != NULL
4585 ? (*p
)->output_section()->name() : "(special)"));
4587 // We want to ignore the size of a SHF_TLS SHT_NOBITS
4588 // section. Such a section does not affect the size of a
4590 if (!(*p
)->is_section_flag_set(elfcpp::SHF_TLS
)
4591 || !(*p
)->is_section_type(elfcpp::SHT_NOBITS
))
4592 off
+= (*p
)->data_size();
4597 if ((*p
)->is_section())
4599 (*p
)->set_out_shndx(*pshndx
);
4605 return addr
+ (maxoff
- startoff
);
4608 // For a non-PT_LOAD segment, set the offset from the sections, if
4609 // any. Add INCREASE to the file size and the memory size.
4612 Output_segment::set_offset(unsigned int increase
)
4614 gold_assert(this->type_
!= elfcpp::PT_LOAD
);
4616 gold_assert(!this->are_addresses_set_
);
4618 // A non-load section only uses output_lists_[0].
4620 Output_data_list
* pdl
= &this->output_lists_
[0];
4624 gold_assert(increase
== 0);
4627 this->are_addresses_set_
= true;
4629 this->min_p_align_
= 0;
4635 // Find the first and last section by address.
4636 const Output_data
* first
= NULL
;
4637 const Output_data
* last_data
= NULL
;
4638 const Output_data
* last_bss
= NULL
;
4639 for (Output_data_list::const_iterator p
= pdl
->begin();
4644 || (*p
)->address() < first
->address()
4645 || ((*p
)->address() == first
->address()
4646 && (*p
)->data_size() < first
->data_size()))
4648 const Output_data
** plast
;
4649 if ((*p
)->is_section()
4650 && (*p
)->output_section()->type() == elfcpp::SHT_NOBITS
)
4655 || (*p
)->address() > (*plast
)->address()
4656 || ((*p
)->address() == (*plast
)->address()
4657 && (*p
)->data_size() > (*plast
)->data_size()))
4661 this->vaddr_
= first
->address();
4662 this->paddr_
= (first
->has_load_address()
4663 ? first
->load_address()
4665 this->are_addresses_set_
= true;
4666 this->offset_
= first
->offset();
4668 if (last_data
== NULL
)
4671 this->filesz_
= (last_data
->address()
4672 + last_data
->data_size()
4675 const Output_data
* last
= last_bss
!= NULL
? last_bss
: last_data
;
4676 this->memsz_
= (last
->address()
4680 this->filesz_
+= increase
;
4681 this->memsz_
+= increase
;
4683 // If this is a RELRO segment, verify that the segment ends at a
4685 if (this->type_
== elfcpp::PT_GNU_RELRO
)
4687 uint64_t page_align
= parameters
->target().abi_pagesize();
4688 uint64_t segment_end
= this->vaddr_
+ this->memsz_
;
4689 if (parameters
->incremental_update())
4691 // The INCREASE_RELRO calculation is bypassed for an incremental
4692 // update, so we need to adjust the segment size manually here.
4693 segment_end
= align_address(segment_end
, page_align
);
4694 this->memsz_
= segment_end
- this->vaddr_
;
4697 gold_assert(segment_end
== align_address(segment_end
, page_align
));
4700 // If this is a TLS segment, align the memory size. The code in
4701 // set_section_list ensures that the section after the TLS segment
4702 // is aligned to give us room.
4703 if (this->type_
== elfcpp::PT_TLS
)
4705 uint64_t segment_align
= this->maximum_alignment();
4706 gold_assert(this->vaddr_
== align_address(this->vaddr_
, segment_align
));
4707 this->memsz_
= align_address(this->memsz_
, segment_align
);
4711 // Set the TLS offsets of the sections in the PT_TLS segment.
4714 Output_segment::set_tls_offsets()
4716 gold_assert(this->type_
== elfcpp::PT_TLS
);
4718 for (Output_data_list::iterator p
= this->output_lists_
[0].begin();
4719 p
!= this->output_lists_
[0].end();
4721 (*p
)->set_tls_offset(this->vaddr_
);
4724 // Return the first section.
4727 Output_segment::first_section() const
4729 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4731 const Output_data_list
* pdl
= &this->output_lists_
[i
];
4732 for (Output_data_list::const_iterator p
= pdl
->begin();
4736 if ((*p
)->is_section())
4737 return (*p
)->output_section();
4743 // Return the number of Output_sections in an Output_segment.
4746 Output_segment::output_section_count() const
4748 unsigned int ret
= 0;
4749 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4750 ret
+= this->output_section_count_list(&this->output_lists_
[i
]);
4754 // Return the number of Output_sections in an Output_data_list.
4757 Output_segment::output_section_count_list(const Output_data_list
* pdl
) const
4759 unsigned int count
= 0;
4760 for (Output_data_list::const_iterator p
= pdl
->begin();
4764 if ((*p
)->is_section())
4770 // Return the section attached to the list segment with the lowest
4771 // load address. This is used when handling a PHDRS clause in a
4775 Output_segment::section_with_lowest_load_address() const
4777 Output_section
* found
= NULL
;
4778 uint64_t found_lma
= 0;
4779 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4780 this->lowest_load_address_in_list(&this->output_lists_
[i
], &found
,
4785 // Look through a list for a section with a lower load address.
4788 Output_segment::lowest_load_address_in_list(const Output_data_list
* pdl
,
4789 Output_section
** found
,
4790 uint64_t* found_lma
) const
4792 for (Output_data_list::const_iterator p
= pdl
->begin();
4796 if (!(*p
)->is_section())
4798 Output_section
* os
= static_cast<Output_section
*>(*p
);
4799 uint64_t lma
= (os
->has_load_address()
4800 ? os
->load_address()
4802 if (*found
== NULL
|| lma
< *found_lma
)
4810 // Write the segment data into *OPHDR.
4812 template<int size
, bool big_endian
>
4814 Output_segment::write_header(elfcpp::Phdr_write
<size
, big_endian
>* ophdr
)
4816 ophdr
->put_p_type(this->type_
);
4817 ophdr
->put_p_offset(this->offset_
);
4818 ophdr
->put_p_vaddr(this->vaddr_
);
4819 ophdr
->put_p_paddr(this->paddr_
);
4820 ophdr
->put_p_filesz(this->filesz_
);
4821 ophdr
->put_p_memsz(this->memsz_
);
4822 ophdr
->put_p_flags(this->flags_
);
4823 ophdr
->put_p_align(std::max(this->min_p_align_
, this->maximum_alignment()));
4826 // Write the section headers into V.
4828 template<int size
, bool big_endian
>
4830 Output_segment::write_section_headers(const Layout
* layout
,
4831 const Stringpool
* secnamepool
,
4833 unsigned int* pshndx
) const
4835 // Every section that is attached to a segment must be attached to a
4836 // PT_LOAD segment, so we only write out section headers for PT_LOAD
4838 if (this->type_
!= elfcpp::PT_LOAD
)
4841 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4843 const Output_data_list
* pdl
= &this->output_lists_
[i
];
4844 v
= this->write_section_headers_list
<size
, big_endian
>(layout
,
4853 template<int size
, bool big_endian
>
4855 Output_segment::write_section_headers_list(const Layout
* layout
,
4856 const Stringpool
* secnamepool
,
4857 const Output_data_list
* pdl
,
4859 unsigned int* pshndx
) const
4861 const int shdr_size
= elfcpp::Elf_sizes
<size
>::shdr_size
;
4862 for (Output_data_list::const_iterator p
= pdl
->begin();
4866 if ((*p
)->is_section())
4868 const Output_section
* ps
= static_cast<const Output_section
*>(*p
);
4869 gold_assert(*pshndx
== ps
->out_shndx());
4870 elfcpp::Shdr_write
<size
, big_endian
> oshdr(v
);
4871 ps
->write_header(layout
, secnamepool
, &oshdr
);
4879 // Print the output sections to the map file.
4882 Output_segment::print_sections_to_mapfile(Mapfile
* mapfile
) const
4884 if (this->type() != elfcpp::PT_LOAD
)
4886 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4887 this->print_section_list_to_mapfile(mapfile
, &this->output_lists_
[i
]);
4890 // Print an output section list to the map file.
4893 Output_segment::print_section_list_to_mapfile(Mapfile
* mapfile
,
4894 const Output_data_list
* pdl
) const
4896 for (Output_data_list::const_iterator p
= pdl
->begin();
4899 (*p
)->print_to_mapfile(mapfile
);
4902 // Output_file methods.
4904 Output_file::Output_file(const char* name
)
4909 map_is_anonymous_(false),
4910 map_is_allocated_(false),
4911 is_temporary_(false)
4915 // Try to open an existing file. Returns false if the file doesn't
4916 // exist, has a size of 0 or can't be mmapped. If BASE_NAME is not
4917 // NULL, open that file as the base for incremental linking, and
4918 // copy its contents to the new output file. This routine can
4919 // be called for incremental updates, in which case WRITABLE should
4920 // be true, or by the incremental-dump utility, in which case
4921 // WRITABLE should be false.
4924 Output_file::open_base_file(const char* base_name
, bool writable
)
4926 // The name "-" means "stdout".
4927 if (strcmp(this->name_
, "-") == 0)
4930 bool use_base_file
= base_name
!= NULL
;
4932 base_name
= this->name_
;
4933 else if (strcmp(base_name
, this->name_
) == 0)
4934 gold_fatal(_("%s: incremental base and output file name are the same"),
4937 // Don't bother opening files with a size of zero.
4939 if (::stat(base_name
, &s
) != 0)
4941 gold_info(_("%s: stat: %s"), base_name
, strerror(errno
));
4946 gold_info(_("%s: incremental base file is empty"), base_name
);
4950 // If we're using a base file, we want to open it read-only.
4954 int oflags
= writable
? O_RDWR
: O_RDONLY
;
4955 int o
= open_descriptor(-1, base_name
, oflags
, 0);
4958 gold_info(_("%s: open: %s"), base_name
, strerror(errno
));
4962 // If the base file and the output file are different, open a
4963 // new output file and read the contents from the base file into
4964 // the newly-mapped region.
4967 this->open(s
.st_size
);
4968 ssize_t bytes_to_read
= s
.st_size
;
4969 unsigned char* p
= this->base_
;
4970 while (bytes_to_read
> 0)
4972 ssize_t len
= ::read(o
, p
, bytes_to_read
);
4975 gold_info(_("%s: read failed: %s"), base_name
, strerror(errno
));
4980 gold_info(_("%s: file too short: read only %lld of %lld bytes"),
4982 static_cast<long long>(s
.st_size
- bytes_to_read
),
4983 static_cast<long long>(s
.st_size
));
4987 bytes_to_read
-= len
;
4994 this->file_size_
= s
.st_size
;
4996 if (!this->map_no_anonymous(writable
))
4998 release_descriptor(o
, true);
5000 this->file_size_
= 0;
5007 // Open the output file.
5010 Output_file::open(off_t file_size
)
5012 this->file_size_
= file_size
;
5014 // Unlink the file first; otherwise the open() may fail if the file
5015 // is busy (e.g. it's an executable that's currently being executed).
5017 // However, the linker may be part of a system where a zero-length
5018 // file is created for it to write to, with tight permissions (gcc
5019 // 2.95 did something like this). Unlinking the file would work
5020 // around those permission controls, so we only unlink if the file
5021 // has a non-zero size. We also unlink only regular files to avoid
5022 // trouble with directories/etc.
5024 // If we fail, continue; this command is merely a best-effort attempt
5025 // to improve the odds for open().
5027 // We let the name "-" mean "stdout"
5028 if (!this->is_temporary_
)
5030 if (strcmp(this->name_
, "-") == 0)
5031 this->o_
= STDOUT_FILENO
;
5035 if (::stat(this->name_
, &s
) == 0
5036 && (S_ISREG (s
.st_mode
) || S_ISLNK (s
.st_mode
)))
5039 ::unlink(this->name_
);
5040 else if (!parameters
->options().relocatable())
5042 // If we don't unlink the existing file, add execute
5043 // permission where read permissions already exist
5044 // and where the umask permits.
5045 int mask
= ::umask(0);
5047 s
.st_mode
|= (s
.st_mode
& 0444) >> 2;
5048 ::chmod(this->name_
, s
.st_mode
& ~mask
);
5052 int mode
= parameters
->options().relocatable() ? 0666 : 0777;
5053 int o
= open_descriptor(-1, this->name_
, O_RDWR
| O_CREAT
| O_TRUNC
,
5056 gold_fatal(_("%s: open: %s"), this->name_
, strerror(errno
));
5064 // Resize the output file.
5067 Output_file::resize(off_t file_size
)
5069 // If the mmap is mapping an anonymous memory buffer, this is easy:
5070 // just mremap to the new size. If it's mapping to a file, we want
5071 // to unmap to flush to the file, then remap after growing the file.
5072 if (this->map_is_anonymous_
)
5075 if (!this->map_is_allocated_
)
5077 base
= ::mremap(this->base_
, this->file_size_
, file_size
,
5079 if (base
== MAP_FAILED
)
5080 gold_fatal(_("%s: mremap: %s"), this->name_
, strerror(errno
));
5084 base
= realloc(this->base_
, file_size
);
5087 if (file_size
> this->file_size_
)
5088 memset(static_cast<char*>(base
) + this->file_size_
, 0,
5089 file_size
- this->file_size_
);
5091 this->base_
= static_cast<unsigned char*>(base
);
5092 this->file_size_
= file_size
;
5097 this->file_size_
= file_size
;
5098 if (!this->map_no_anonymous(true))
5099 gold_fatal(_("%s: mmap: %s"), this->name_
, strerror(errno
));
5103 // Map an anonymous block of memory which will later be written to the
5104 // file. Return whether the map succeeded.
5107 Output_file::map_anonymous()
5109 void* base
= ::mmap(NULL
, this->file_size_
, PROT_READ
| PROT_WRITE
,
5110 MAP_PRIVATE
| MAP_ANONYMOUS
, -1, 0);
5111 if (base
== MAP_FAILED
)
5113 base
= malloc(this->file_size_
);
5116 memset(base
, 0, this->file_size_
);
5117 this->map_is_allocated_
= true;
5119 this->base_
= static_cast<unsigned char*>(base
);
5120 this->map_is_anonymous_
= true;
5124 // Map the file into memory. Return whether the mapping succeeded.
5125 // If WRITABLE is true, map with write access.
5128 Output_file::map_no_anonymous(bool writable
)
5130 const int o
= this->o_
;
5132 // If the output file is not a regular file, don't try to mmap it;
5133 // instead, we'll mmap a block of memory (an anonymous buffer), and
5134 // then later write the buffer to the file.
5136 struct stat statbuf
;
5137 if (o
== STDOUT_FILENO
|| o
== STDERR_FILENO
5138 || ::fstat(o
, &statbuf
) != 0
5139 || !S_ISREG(statbuf
.st_mode
)
5140 || this->is_temporary_
)
5143 // Ensure that we have disk space available for the file. If we
5144 // don't do this, it is possible that we will call munmap, close,
5145 // and exit with dirty buffers still in the cache with no assigned
5146 // disk blocks. If the disk is out of space at that point, the
5147 // output file will wind up incomplete, but we will have already
5148 // exited. The alternative to fallocate would be to use fdatasync,
5149 // but that would be a more significant performance hit.
5152 int err
= gold_fallocate(o
, 0, this->file_size_
);
5154 gold_fatal(_("%s: %s"), this->name_
, strerror(err
));
5157 // Map the file into memory.
5158 int prot
= PROT_READ
;
5161 base
= ::mmap(NULL
, this->file_size_
, prot
, MAP_SHARED
, o
, 0);
5163 // The mmap call might fail because of file system issues: the file
5164 // system might not support mmap at all, or it might not support
5165 // mmap with PROT_WRITE.
5166 if (base
== MAP_FAILED
)
5169 this->map_is_anonymous_
= false;
5170 this->base_
= static_cast<unsigned char*>(base
);
5174 // Map the file into memory.
5179 if (parameters
->options().mmap_output_file()
5180 && this->map_no_anonymous(true))
5183 // The mmap call might fail because of file system issues: the file
5184 // system might not support mmap at all, or it might not support
5185 // mmap with PROT_WRITE. I'm not sure which errno values we will
5186 // see in all cases, so if the mmap fails for any reason and we
5187 // don't care about file contents, try for an anonymous map.
5188 if (this->map_anonymous())
5191 gold_fatal(_("%s: mmap: failed to allocate %lu bytes for output file: %s"),
5192 this->name_
, static_cast<unsigned long>(this->file_size_
),
5196 // Unmap the file from memory.
5199 Output_file::unmap()
5201 if (this->map_is_anonymous_
)
5203 // We've already written out the data, so there is no reason to
5204 // waste time unmapping or freeing the memory.
5208 if (::munmap(this->base_
, this->file_size_
) < 0)
5209 gold_error(_("%s: munmap: %s"), this->name_
, strerror(errno
));
5214 // Close the output file.
5217 Output_file::close()
5219 // If the map isn't file-backed, we need to write it now.
5220 if (this->map_is_anonymous_
&& !this->is_temporary_
)
5222 size_t bytes_to_write
= this->file_size_
;
5224 while (bytes_to_write
> 0)
5226 ssize_t bytes_written
= ::write(this->o_
, this->base_
+ offset
,
5228 if (bytes_written
== 0)
5229 gold_error(_("%s: write: unexpected 0 return-value"), this->name_
);
5230 else if (bytes_written
< 0)
5231 gold_error(_("%s: write: %s"), this->name_
, strerror(errno
));
5234 bytes_to_write
-= bytes_written
;
5235 offset
+= bytes_written
;
5241 // We don't close stdout or stderr
5242 if (this->o_
!= STDOUT_FILENO
5243 && this->o_
!= STDERR_FILENO
5244 && !this->is_temporary_
)
5245 if (::close(this->o_
) < 0)
5246 gold_error(_("%s: close: %s"), this->name_
, strerror(errno
));
5250 // Instantiate the templates we need. We could use the configure
5251 // script to restrict this to only the ones for implemented targets.
5253 #ifdef HAVE_TARGET_32_LITTLE
5256 Output_section::add_input_section
<32, false>(
5258 Sized_relobj_file
<32, false>* object
,
5260 const char* secname
,
5261 const elfcpp::Shdr
<32, false>& shdr
,
5262 unsigned int reloc_shndx
,
5263 bool have_sections_script
);
5266 #ifdef HAVE_TARGET_32_BIG
5269 Output_section::add_input_section
<32, true>(
5271 Sized_relobj_file
<32, true>* object
,
5273 const char* secname
,
5274 const elfcpp::Shdr
<32, true>& shdr
,
5275 unsigned int reloc_shndx
,
5276 bool have_sections_script
);
5279 #ifdef HAVE_TARGET_64_LITTLE
5282 Output_section::add_input_section
<64, false>(
5284 Sized_relobj_file
<64, false>* object
,
5286 const char* secname
,
5287 const elfcpp::Shdr
<64, false>& shdr
,
5288 unsigned int reloc_shndx
,
5289 bool have_sections_script
);
5292 #ifdef HAVE_TARGET_64_BIG
5295 Output_section::add_input_section
<64, true>(
5297 Sized_relobj_file
<64, true>* object
,
5299 const char* secname
,
5300 const elfcpp::Shdr
<64, true>& shdr
,
5301 unsigned int reloc_shndx
,
5302 bool have_sections_script
);
5305 #ifdef HAVE_TARGET_32_LITTLE
5307 class Output_reloc
<elfcpp::SHT_REL
, false, 32, false>;
5310 #ifdef HAVE_TARGET_32_BIG
5312 class Output_reloc
<elfcpp::SHT_REL
, false, 32, true>;
5315 #ifdef HAVE_TARGET_64_LITTLE
5317 class Output_reloc
<elfcpp::SHT_REL
, false, 64, false>;
5320 #ifdef HAVE_TARGET_64_BIG
5322 class Output_reloc
<elfcpp::SHT_REL
, false, 64, true>;
5325 #ifdef HAVE_TARGET_32_LITTLE
5327 class Output_reloc
<elfcpp::SHT_REL
, true, 32, false>;
5330 #ifdef HAVE_TARGET_32_BIG
5332 class Output_reloc
<elfcpp::SHT_REL
, true, 32, true>;
5335 #ifdef HAVE_TARGET_64_LITTLE
5337 class Output_reloc
<elfcpp::SHT_REL
, true, 64, false>;
5340 #ifdef HAVE_TARGET_64_BIG
5342 class Output_reloc
<elfcpp::SHT_REL
, true, 64, true>;
5345 #ifdef HAVE_TARGET_32_LITTLE
5347 class Output_reloc
<elfcpp::SHT_RELA
, false, 32, false>;
5350 #ifdef HAVE_TARGET_32_BIG
5352 class Output_reloc
<elfcpp::SHT_RELA
, false, 32, true>;
5355 #ifdef HAVE_TARGET_64_LITTLE
5357 class Output_reloc
<elfcpp::SHT_RELA
, false, 64, false>;
5360 #ifdef HAVE_TARGET_64_BIG
5362 class Output_reloc
<elfcpp::SHT_RELA
, false, 64, true>;
5365 #ifdef HAVE_TARGET_32_LITTLE
5367 class Output_reloc
<elfcpp::SHT_RELA
, true, 32, false>;
5370 #ifdef HAVE_TARGET_32_BIG
5372 class Output_reloc
<elfcpp::SHT_RELA
, true, 32, true>;
5375 #ifdef HAVE_TARGET_64_LITTLE
5377 class Output_reloc
<elfcpp::SHT_RELA
, true, 64, false>;
5380 #ifdef HAVE_TARGET_64_BIG
5382 class Output_reloc
<elfcpp::SHT_RELA
, true, 64, true>;
5385 #ifdef HAVE_TARGET_32_LITTLE
5387 class Output_data_reloc
<elfcpp::SHT_REL
, false, 32, false>;
5390 #ifdef HAVE_TARGET_32_BIG
5392 class Output_data_reloc
<elfcpp::SHT_REL
, false, 32, true>;
5395 #ifdef HAVE_TARGET_64_LITTLE
5397 class Output_data_reloc
<elfcpp::SHT_REL
, false, 64, false>;
5400 #ifdef HAVE_TARGET_64_BIG
5402 class Output_data_reloc
<elfcpp::SHT_REL
, false, 64, true>;
5405 #ifdef HAVE_TARGET_32_LITTLE
5407 class Output_data_reloc
<elfcpp::SHT_REL
, true, 32, false>;
5410 #ifdef HAVE_TARGET_32_BIG
5412 class Output_data_reloc
<elfcpp::SHT_REL
, true, 32, true>;
5415 #ifdef HAVE_TARGET_64_LITTLE
5417 class Output_data_reloc
<elfcpp::SHT_REL
, true, 64, false>;
5420 #ifdef HAVE_TARGET_64_BIG
5422 class Output_data_reloc
<elfcpp::SHT_REL
, true, 64, true>;
5425 #ifdef HAVE_TARGET_32_LITTLE
5427 class Output_data_reloc
<elfcpp::SHT_RELA
, false, 32, false>;
5430 #ifdef HAVE_TARGET_32_BIG
5432 class Output_data_reloc
<elfcpp::SHT_RELA
, false, 32, true>;
5435 #ifdef HAVE_TARGET_64_LITTLE
5437 class Output_data_reloc
<elfcpp::SHT_RELA
, false, 64, false>;
5440 #ifdef HAVE_TARGET_64_BIG
5442 class Output_data_reloc
<elfcpp::SHT_RELA
, false, 64, true>;
5445 #ifdef HAVE_TARGET_32_LITTLE
5447 class Output_data_reloc
<elfcpp::SHT_RELA
, true, 32, false>;
5450 #ifdef HAVE_TARGET_32_BIG
5452 class Output_data_reloc
<elfcpp::SHT_RELA
, true, 32, true>;
5455 #ifdef HAVE_TARGET_64_LITTLE
5457 class Output_data_reloc
<elfcpp::SHT_RELA
, true, 64, false>;
5460 #ifdef HAVE_TARGET_64_BIG
5462 class Output_data_reloc
<elfcpp::SHT_RELA
, true, 64, true>;
5465 #ifdef HAVE_TARGET_32_LITTLE
5467 class Output_relocatable_relocs
<elfcpp::SHT_REL
, 32, false>;
5470 #ifdef HAVE_TARGET_32_BIG
5472 class Output_relocatable_relocs
<elfcpp::SHT_REL
, 32, true>;
5475 #ifdef HAVE_TARGET_64_LITTLE
5477 class Output_relocatable_relocs
<elfcpp::SHT_REL
, 64, false>;
5480 #ifdef HAVE_TARGET_64_BIG
5482 class Output_relocatable_relocs
<elfcpp::SHT_REL
, 64, true>;
5485 #ifdef HAVE_TARGET_32_LITTLE
5487 class Output_relocatable_relocs
<elfcpp::SHT_RELA
, 32, false>;
5490 #ifdef HAVE_TARGET_32_BIG
5492 class Output_relocatable_relocs
<elfcpp::SHT_RELA
, 32, true>;
5495 #ifdef HAVE_TARGET_64_LITTLE
5497 class Output_relocatable_relocs
<elfcpp::SHT_RELA
, 64, false>;
5500 #ifdef HAVE_TARGET_64_BIG
5502 class Output_relocatable_relocs
<elfcpp::SHT_RELA
, 64, true>;
5505 #ifdef HAVE_TARGET_32_LITTLE
5507 class Output_data_group
<32, false>;
5510 #ifdef HAVE_TARGET_32_BIG
5512 class Output_data_group
<32, true>;
5515 #ifdef HAVE_TARGET_64_LITTLE
5517 class Output_data_group
<64, false>;
5520 #ifdef HAVE_TARGET_64_BIG
5522 class Output_data_group
<64, true>;
5526 class Output_data_got
<32, false>;
5529 class Output_data_got
<32, true>;
5532 class Output_data_got
<64, false>;
5535 class Output_data_got
<64, true>;
5537 } // End namespace gold.