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 relocation.
856 template<bool dynamic
, int size
, bool big_endian
>
857 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::Output_reloc(
861 : address_(address
), local_sym_index_(0), type_(type
),
862 is_relative_(false), is_symbolless_(false),
863 is_section_symbol_(false), use_plt_offset_(false), shndx_(INVALID_CODE
)
865 // this->type_ is a bitfield; make sure TYPE fits.
866 gold_assert(this->type_
== type
);
867 this->u1_
.relobj
= NULL
;
871 template<bool dynamic
, int size
, bool big_endian
>
872 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::Output_reloc(
874 Sized_relobj
<size
, big_endian
>* relobj
,
877 : address_(address
), local_sym_index_(0), type_(type
),
878 is_relative_(false), is_symbolless_(false),
879 is_section_symbol_(false), use_plt_offset_(false), shndx_(shndx
)
881 gold_assert(shndx
!= INVALID_CODE
);
882 // this->type_ is a bitfield; make sure TYPE fits.
883 gold_assert(this->type_
== type
);
884 this->u1_
.relobj
= NULL
;
885 this->u2_
.relobj
= relobj
;
888 // A target specific relocation.
890 template<bool dynamic
, int size
, bool big_endian
>
891 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::Output_reloc(
896 : address_(address
), local_sym_index_(TARGET_CODE
), type_(type
),
897 is_relative_(false), is_symbolless_(false),
898 is_section_symbol_(false), use_plt_offset_(false), shndx_(INVALID_CODE
)
900 // this->type_ is a bitfield; make sure TYPE fits.
901 gold_assert(this->type_
== type
);
906 template<bool dynamic
, int size
, bool big_endian
>
907 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::Output_reloc(
910 Sized_relobj
<size
, big_endian
>* relobj
,
913 : address_(address
), local_sym_index_(TARGET_CODE
), type_(type
),
914 is_relative_(false), is_symbolless_(false),
915 is_section_symbol_(false), use_plt_offset_(false), shndx_(shndx
)
917 gold_assert(shndx
!= INVALID_CODE
);
918 // this->type_ is a bitfield; make sure TYPE fits.
919 gold_assert(this->type_
== type
);
921 this->u2_
.relobj
= relobj
;
924 // Record that we need a dynamic symbol index for this relocation.
926 template<bool dynamic
, int size
, bool big_endian
>
928 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::
929 set_needs_dynsym_index()
931 if (this->is_symbolless_
)
933 switch (this->local_sym_index_
)
939 this->u1_
.gsym
->set_needs_dynsym_entry();
943 this->u1_
.os
->set_needs_dynsym_index();
947 // The target must take care of this if necessary.
955 const unsigned int lsi
= this->local_sym_index_
;
956 Sized_relobj_file
<size
, big_endian
>* relobj
=
957 this->u1_
.relobj
->sized_relobj();
958 gold_assert(relobj
!= NULL
);
959 if (!this->is_section_symbol_
)
960 relobj
->set_needs_output_dynsym_entry(lsi
);
962 relobj
->output_section(lsi
)->set_needs_dynsym_index();
968 // Get the symbol index of a relocation.
970 template<bool dynamic
, int size
, bool big_endian
>
972 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::get_symbol_index()
976 if (this->is_symbolless_
)
978 switch (this->local_sym_index_
)
984 if (this->u1_
.gsym
== NULL
)
987 index
= this->u1_
.gsym
->dynsym_index();
989 index
= this->u1_
.gsym
->symtab_index();
994 index
= this->u1_
.os
->dynsym_index();
996 index
= this->u1_
.os
->symtab_index();
1000 index
= parameters
->target().reloc_symbol_index(this->u1_
.arg
,
1005 // Relocations without symbols use a symbol index of 0.
1011 const unsigned int lsi
= this->local_sym_index_
;
1012 Sized_relobj_file
<size
, big_endian
>* relobj
=
1013 this->u1_
.relobj
->sized_relobj();
1014 gold_assert(relobj
!= NULL
);
1015 if (!this->is_section_symbol_
)
1018 index
= relobj
->dynsym_index(lsi
);
1020 index
= relobj
->symtab_index(lsi
);
1024 Output_section
* os
= relobj
->output_section(lsi
);
1025 gold_assert(os
!= NULL
);
1027 index
= os
->dynsym_index();
1029 index
= os
->symtab_index();
1034 gold_assert(index
!= -1U);
1038 // For a local section symbol, get the address of the offset ADDEND
1039 // within the input section.
1041 template<bool dynamic
, int size
, bool big_endian
>
1042 typename
elfcpp::Elf_types
<size
>::Elf_Addr
1043 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::
1044 local_section_offset(Addend addend
) const
1046 gold_assert(this->local_sym_index_
!= GSYM_CODE
1047 && this->local_sym_index_
!= SECTION_CODE
1048 && this->local_sym_index_
!= TARGET_CODE
1049 && this->local_sym_index_
!= INVALID_CODE
1050 && this->local_sym_index_
!= 0
1051 && this->is_section_symbol_
);
1052 const unsigned int lsi
= this->local_sym_index_
;
1053 Output_section
* os
= this->u1_
.relobj
->output_section(lsi
);
1054 gold_assert(os
!= NULL
);
1055 Address offset
= this->u1_
.relobj
->get_output_section_offset(lsi
);
1056 if (offset
!= invalid_address
)
1057 return offset
+ addend
;
1058 // This is a merge section.
1059 Sized_relobj_file
<size
, big_endian
>* relobj
=
1060 this->u1_
.relobj
->sized_relobj();
1061 gold_assert(relobj
!= NULL
);
1062 offset
= os
->output_address(relobj
, lsi
, addend
);
1063 gold_assert(offset
!= invalid_address
);
1067 // Get the output address of a relocation.
1069 template<bool dynamic
, int size
, bool big_endian
>
1070 typename
elfcpp::Elf_types
<size
>::Elf_Addr
1071 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::get_address() const
1073 Address address
= this->address_
;
1074 if (this->shndx_
!= INVALID_CODE
)
1076 Output_section
* os
= this->u2_
.relobj
->output_section(this->shndx_
);
1077 gold_assert(os
!= NULL
);
1078 Address off
= this->u2_
.relobj
->get_output_section_offset(this->shndx_
);
1079 if (off
!= invalid_address
)
1080 address
+= os
->address() + off
;
1083 Sized_relobj_file
<size
, big_endian
>* relobj
=
1084 this->u2_
.relobj
->sized_relobj();
1085 gold_assert(relobj
!= NULL
);
1086 address
= os
->output_address(relobj
, this->shndx_
, address
);
1087 gold_assert(address
!= invalid_address
);
1090 else if (this->u2_
.od
!= NULL
)
1091 address
+= this->u2_
.od
->address();
1095 // Write out the offset and info fields of a Rel or Rela relocation
1098 template<bool dynamic
, int size
, bool big_endian
>
1099 template<typename Write_rel
>
1101 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::write_rel(
1102 Write_rel
* wr
) const
1104 wr
->put_r_offset(this->get_address());
1105 unsigned int sym_index
= this->get_symbol_index();
1106 wr
->put_r_info(elfcpp::elf_r_info
<size
>(sym_index
, this->type_
));
1109 // Write out a Rel relocation.
1111 template<bool dynamic
, int size
, bool big_endian
>
1113 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::write(
1114 unsigned char* pov
) const
1116 elfcpp::Rel_write
<size
, big_endian
> orel(pov
);
1117 this->write_rel(&orel
);
1120 // Get the value of the symbol referred to by a Rel relocation.
1122 template<bool dynamic
, int size
, bool big_endian
>
1123 typename
elfcpp::Elf_types
<size
>::Elf_Addr
1124 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::symbol_value(
1125 Addend addend
) const
1127 if (this->local_sym_index_
== GSYM_CODE
)
1129 const Sized_symbol
<size
>* sym
;
1130 sym
= static_cast<const Sized_symbol
<size
>*>(this->u1_
.gsym
);
1131 if (this->use_plt_offset_
&& sym
->has_plt_offset())
1132 return parameters
->target().plt_address_for_global(sym
);
1134 return sym
->value() + addend
;
1136 if (this->local_sym_index_
== SECTION_CODE
)
1138 gold_assert(!this->use_plt_offset_
);
1139 return this->u1_
.os
->address() + addend
;
1141 gold_assert(this->local_sym_index_
!= TARGET_CODE
1142 && this->local_sym_index_
!= INVALID_CODE
1143 && this->local_sym_index_
!= 0
1144 && !this->is_section_symbol_
);
1145 const unsigned int lsi
= this->local_sym_index_
;
1146 Sized_relobj_file
<size
, big_endian
>* relobj
=
1147 this->u1_
.relobj
->sized_relobj();
1148 gold_assert(relobj
!= NULL
);
1149 if (this->use_plt_offset_
)
1150 return parameters
->target().plt_address_for_local(relobj
, lsi
);
1151 const Symbol_value
<size
>* symval
= relobj
->local_symbol(lsi
);
1152 return symval
->value(relobj
, addend
);
1155 // Reloc comparison. This function sorts the dynamic relocs for the
1156 // benefit of the dynamic linker. First we sort all relative relocs
1157 // to the front. Among relative relocs, we sort by output address.
1158 // Among non-relative relocs, we sort by symbol index, then by output
1161 template<bool dynamic
, int size
, bool big_endian
>
1163 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::
1164 compare(const Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>& r2
)
1167 if (this->is_relative_
)
1169 if (!r2
.is_relative_
)
1171 // Otherwise sort by reloc address below.
1173 else if (r2
.is_relative_
)
1177 unsigned int sym1
= this->get_symbol_index();
1178 unsigned int sym2
= r2
.get_symbol_index();
1181 else if (sym1
> sym2
)
1183 // Otherwise sort by reloc address.
1186 section_offset_type addr1
= this->get_address();
1187 section_offset_type addr2
= r2
.get_address();
1190 else if (addr1
> addr2
)
1193 // Final tie breaker, in order to generate the same output on any
1194 // host: reloc type.
1195 unsigned int type1
= this->type_
;
1196 unsigned int type2
= r2
.type_
;
1199 else if (type1
> type2
)
1202 // These relocs appear to be exactly the same.
1206 // Write out a Rela relocation.
1208 template<bool dynamic
, int size
, bool big_endian
>
1210 Output_reloc
<elfcpp::SHT_RELA
, dynamic
, size
, big_endian
>::write(
1211 unsigned char* pov
) const
1213 elfcpp::Rela_write
<size
, big_endian
> orel(pov
);
1214 this->rel_
.write_rel(&orel
);
1215 Addend addend
= this->addend_
;
1216 if (this->rel_
.is_target_specific())
1217 addend
= parameters
->target().reloc_addend(this->rel_
.target_arg(),
1218 this->rel_
.type(), addend
);
1219 else if (this->rel_
.is_symbolless())
1220 addend
= this->rel_
.symbol_value(addend
);
1221 else if (this->rel_
.is_local_section_symbol())
1222 addend
= this->rel_
.local_section_offset(addend
);
1223 orel
.put_r_addend(addend
);
1226 // Output_data_reloc_base methods.
1228 // Adjust the output section.
1230 template<int sh_type
, bool dynamic
, int size
, bool big_endian
>
1232 Output_data_reloc_base
<sh_type
, dynamic
, size
, big_endian
>
1233 ::do_adjust_output_section(Output_section
* os
)
1235 if (sh_type
== elfcpp::SHT_REL
)
1236 os
->set_entsize(elfcpp::Elf_sizes
<size
>::rel_size
);
1237 else if (sh_type
== elfcpp::SHT_RELA
)
1238 os
->set_entsize(elfcpp::Elf_sizes
<size
>::rela_size
);
1242 // A STT_GNU_IFUNC symbol may require a IRELATIVE reloc when doing a
1243 // static link. The backends will generate a dynamic reloc section
1244 // to hold this. In that case we don't want to link to the dynsym
1245 // section, because there isn't one.
1247 os
->set_should_link_to_symtab();
1248 else if (parameters
->doing_static_link())
1251 os
->set_should_link_to_dynsym();
1254 // Write out relocation data.
1256 template<int sh_type
, bool dynamic
, int size
, bool big_endian
>
1258 Output_data_reloc_base
<sh_type
, dynamic
, size
, big_endian
>::do_write(
1261 const off_t off
= this->offset();
1262 const off_t oview_size
= this->data_size();
1263 unsigned char* const oview
= of
->get_output_view(off
, oview_size
);
1265 if (this->sort_relocs())
1267 gold_assert(dynamic
);
1268 std::sort(this->relocs_
.begin(), this->relocs_
.end(),
1269 Sort_relocs_comparison());
1272 unsigned char* pov
= oview
;
1273 for (typename
Relocs::const_iterator p
= this->relocs_
.begin();
1274 p
!= this->relocs_
.end();
1281 gold_assert(pov
- oview
== oview_size
);
1283 of
->write_output_view(off
, oview_size
, oview
);
1285 // We no longer need the relocation entries.
1286 this->relocs_
.clear();
1289 // Class Output_relocatable_relocs.
1291 template<int sh_type
, int size
, bool big_endian
>
1293 Output_relocatable_relocs
<sh_type
, size
, big_endian
>::set_final_data_size()
1295 this->set_data_size(this->rr_
->output_reloc_count()
1296 * Reloc_types
<sh_type
, size
, big_endian
>::reloc_size
);
1299 // class Output_data_group.
1301 template<int size
, bool big_endian
>
1302 Output_data_group
<size
, big_endian
>::Output_data_group(
1303 Sized_relobj_file
<size
, big_endian
>* relobj
,
1304 section_size_type entry_count
,
1305 elfcpp::Elf_Word flags
,
1306 std::vector
<unsigned int>* input_shndxes
)
1307 : Output_section_data(entry_count
* 4, 4, false),
1311 this->input_shndxes_
.swap(*input_shndxes
);
1314 // Write out the section group, which means translating the section
1315 // indexes to apply to the output file.
1317 template<int size
, bool big_endian
>
1319 Output_data_group
<size
, big_endian
>::do_write(Output_file
* of
)
1321 const off_t off
= this->offset();
1322 const section_size_type oview_size
=
1323 convert_to_section_size_type(this->data_size());
1324 unsigned char* const oview
= of
->get_output_view(off
, oview_size
);
1326 elfcpp::Elf_Word
* contents
= reinterpret_cast<elfcpp::Elf_Word
*>(oview
);
1327 elfcpp::Swap
<32, big_endian
>::writeval(contents
, this->flags_
);
1330 for (std::vector
<unsigned int>::const_iterator p
=
1331 this->input_shndxes_
.begin();
1332 p
!= this->input_shndxes_
.end();
1335 Output_section
* os
= this->relobj_
->output_section(*p
);
1337 unsigned int output_shndx
;
1339 output_shndx
= os
->out_shndx();
1342 this->relobj_
->error(_("section group retained but "
1343 "group element discarded"));
1347 elfcpp::Swap
<32, big_endian
>::writeval(contents
, output_shndx
);
1350 size_t wrote
= reinterpret_cast<unsigned char*>(contents
) - oview
;
1351 gold_assert(wrote
== oview_size
);
1353 of
->write_output_view(off
, oview_size
, oview
);
1355 // We no longer need this information.
1356 this->input_shndxes_
.clear();
1359 // Output_data_got::Got_entry methods.
1361 // Write out the entry.
1363 template<int got_size
, bool big_endian
>
1365 Output_data_got
<got_size
, big_endian
>::Got_entry::write(
1366 unsigned int got_indx
,
1367 unsigned char* pov
) const
1371 switch (this->local_sym_index_
)
1375 // If the symbol is resolved locally, we need to write out the
1376 // link-time value, which will be relocated dynamically by a
1377 // RELATIVE relocation.
1378 Symbol
* gsym
= this->u_
.gsym
;
1379 if (this->use_plt_or_tls_offset_
&& gsym
->has_plt_offset())
1380 val
= parameters
->target().plt_address_for_global(gsym
);
1383 switch (parameters
->size_and_endianness())
1385 #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
1386 case Parameters::TARGET_32_LITTLE
:
1387 case Parameters::TARGET_32_BIG
:
1389 // This cast is ugly. We don't want to put a
1390 // virtual method in Symbol, because we want Symbol
1391 // to be as small as possible.
1392 Sized_symbol
<32>::Value_type v
;
1393 v
= static_cast<Sized_symbol
<32>*>(gsym
)->value();
1394 val
= convert_types
<Valtype
, Sized_symbol
<32>::Value_type
>(v
);
1398 #if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
1399 case Parameters::TARGET_64_LITTLE
:
1400 case Parameters::TARGET_64_BIG
:
1402 Sized_symbol
<64>::Value_type v
;
1403 v
= static_cast<Sized_symbol
<64>*>(gsym
)->value();
1404 val
= convert_types
<Valtype
, Sized_symbol
<64>::Value_type
>(v
);
1411 if (this->use_plt_or_tls_offset_
1412 && gsym
->type() == elfcpp::STT_TLS
)
1413 val
+= parameters
->target().tls_offset_for_global(gsym
,
1420 val
= this->u_
.constant
;
1424 // If we're doing an incremental update, don't touch this GOT entry.
1425 if (parameters
->incremental_update())
1427 val
= this->u_
.constant
;
1432 const Relobj
* object
= this->u_
.object
;
1433 const unsigned int lsi
= this->local_sym_index_
;
1434 bool is_tls
= object
->local_is_tls(lsi
);
1435 if (this->use_plt_or_tls_offset_
&& !is_tls
)
1436 val
= parameters
->target().plt_address_for_local(object
, lsi
);
1439 uint64_t lval
= object
->local_symbol_value(lsi
, 0);
1440 val
= convert_types
<Valtype
, uint64_t>(lval
);
1441 if (this->use_plt_or_tls_offset_
&& is_tls
)
1442 val
+= parameters
->target().tls_offset_for_local(object
, lsi
,
1449 elfcpp::Swap
<got_size
, big_endian
>::writeval(pov
, val
);
1452 // Output_data_got methods.
1454 // Add an entry for a global symbol to the GOT. This returns true if
1455 // this is a new GOT entry, false if the symbol already had a GOT
1458 template<int got_size
, bool big_endian
>
1460 Output_data_got
<got_size
, big_endian
>::add_global(
1462 unsigned int got_type
)
1464 if (gsym
->has_got_offset(got_type
))
1467 unsigned int got_offset
= this->add_got_entry(Got_entry(gsym
, false));
1468 gsym
->set_got_offset(got_type
, got_offset
);
1472 // Like add_global, but use the PLT offset.
1474 template<int got_size
, bool big_endian
>
1476 Output_data_got
<got_size
, big_endian
>::add_global_plt(Symbol
* gsym
,
1477 unsigned int got_type
)
1479 if (gsym
->has_got_offset(got_type
))
1482 unsigned int got_offset
= this->add_got_entry(Got_entry(gsym
, true));
1483 gsym
->set_got_offset(got_type
, got_offset
);
1487 // Add an entry for a global symbol to the GOT, and add a dynamic
1488 // relocation of type R_TYPE for the GOT entry.
1490 template<int got_size
, bool big_endian
>
1492 Output_data_got
<got_size
, big_endian
>::add_global_with_rel(
1494 unsigned int got_type
,
1495 Output_data_reloc_generic
* rel_dyn
,
1496 unsigned int r_type
)
1498 if (gsym
->has_got_offset(got_type
))
1501 unsigned int got_offset
= this->add_got_entry(Got_entry());
1502 gsym
->set_got_offset(got_type
, got_offset
);
1503 rel_dyn
->add_global_generic(gsym
, r_type
, this, got_offset
, 0);
1506 // Add a pair of entries for a global symbol to the GOT, and add
1507 // dynamic relocations of type R_TYPE_1 and R_TYPE_2, respectively.
1508 // If R_TYPE_2 == 0, add the second entry with no relocation.
1509 template<int got_size
, bool big_endian
>
1511 Output_data_got
<got_size
, big_endian
>::add_global_pair_with_rel(
1513 unsigned int got_type
,
1514 Output_data_reloc_generic
* rel_dyn
,
1515 unsigned int r_type_1
,
1516 unsigned int r_type_2
)
1518 if (gsym
->has_got_offset(got_type
))
1521 unsigned int got_offset
= this->add_got_entry_pair(Got_entry(), Got_entry());
1522 gsym
->set_got_offset(got_type
, got_offset
);
1523 rel_dyn
->add_global_generic(gsym
, r_type_1
, this, got_offset
, 0);
1526 rel_dyn
->add_global_generic(gsym
, r_type_2
, this,
1527 got_offset
+ got_size
/ 8, 0);
1530 // Add an entry for a local symbol to the GOT. This returns true if
1531 // this is a new GOT entry, false if the symbol already has a GOT
1534 template<int got_size
, bool big_endian
>
1536 Output_data_got
<got_size
, big_endian
>::add_local(
1538 unsigned int symndx
,
1539 unsigned int got_type
)
1541 if (object
->local_has_got_offset(symndx
, got_type
))
1544 unsigned int got_offset
= this->add_got_entry(Got_entry(object
, symndx
,
1546 object
->set_local_got_offset(symndx
, got_type
, got_offset
);
1550 // Like add_local, but use the PLT offset.
1552 template<int got_size
, bool big_endian
>
1554 Output_data_got
<got_size
, big_endian
>::add_local_plt(
1556 unsigned int symndx
,
1557 unsigned int got_type
)
1559 if (object
->local_has_got_offset(symndx
, got_type
))
1562 unsigned int got_offset
= this->add_got_entry(Got_entry(object
, symndx
,
1564 object
->set_local_got_offset(symndx
, got_type
, got_offset
);
1568 // Add an entry for a local symbol to the GOT, and add a dynamic
1569 // relocation of type R_TYPE for the GOT entry.
1571 template<int got_size
, bool big_endian
>
1573 Output_data_got
<got_size
, big_endian
>::add_local_with_rel(
1575 unsigned int symndx
,
1576 unsigned int got_type
,
1577 Output_data_reloc_generic
* rel_dyn
,
1578 unsigned int r_type
)
1580 if (object
->local_has_got_offset(symndx
, got_type
))
1583 unsigned int got_offset
= this->add_got_entry(Got_entry());
1584 object
->set_local_got_offset(symndx
, got_type
, got_offset
);
1585 rel_dyn
->add_local_generic(object
, symndx
, r_type
, this, got_offset
, 0);
1588 // Add a pair of entries for a local symbol to the GOT, and add
1589 // a dynamic relocation of type R_TYPE using the section symbol of
1590 // the output section to which input section SHNDX maps, on the first.
1591 // The first got entry will have a value of zero, the second the
1592 // value of the local symbol.
1593 template<int got_size
, bool big_endian
>
1595 Output_data_got
<got_size
, big_endian
>::add_local_pair_with_rel(
1597 unsigned int symndx
,
1599 unsigned int got_type
,
1600 Output_data_reloc_generic
* rel_dyn
,
1601 unsigned int r_type
)
1603 if (object
->local_has_got_offset(symndx
, got_type
))
1606 unsigned int got_offset
=
1607 this->add_got_entry_pair(Got_entry(),
1608 Got_entry(object
, symndx
, false));
1609 object
->set_local_got_offset(symndx
, got_type
, got_offset
);
1610 Output_section
* os
= object
->output_section(shndx
);
1611 rel_dyn
->add_output_section_generic(os
, r_type
, this, got_offset
, 0);
1614 // Add a pair of entries for a local symbol to the GOT, and add
1615 // a dynamic relocation of type R_TYPE using STN_UNDEF on the first.
1616 // The first got entry will have a value of zero, the second the
1617 // value of the local symbol offset by Target::tls_offset_for_local.
1618 template<int got_size
, bool big_endian
>
1620 Output_data_got
<got_size
, big_endian
>::add_local_tls_pair(
1622 unsigned int symndx
,
1623 unsigned int got_type
,
1624 Output_data_reloc_generic
* rel_dyn
,
1625 unsigned int r_type
)
1627 if (object
->local_has_got_offset(symndx
, got_type
))
1630 unsigned int got_offset
1631 = this->add_got_entry_pair(Got_entry(),
1632 Got_entry(object
, symndx
, true));
1633 object
->set_local_got_offset(symndx
, got_type
, got_offset
);
1634 rel_dyn
->add_local_generic(object
, 0, r_type
, this, got_offset
, 0);
1637 // Reserve a slot in the GOT for a local symbol or the second slot of a pair.
1639 template<int got_size
, bool big_endian
>
1641 Output_data_got
<got_size
, big_endian
>::reserve_local(
1644 unsigned int sym_index
,
1645 unsigned int got_type
)
1647 this->do_reserve_slot(i
);
1648 object
->set_local_got_offset(sym_index
, got_type
, this->got_offset(i
));
1651 // Reserve a slot in the GOT for a global symbol.
1653 template<int got_size
, bool big_endian
>
1655 Output_data_got
<got_size
, big_endian
>::reserve_global(
1658 unsigned int got_type
)
1660 this->do_reserve_slot(i
);
1661 gsym
->set_got_offset(got_type
, this->got_offset(i
));
1664 // Write out the GOT.
1666 template<int got_size
, bool big_endian
>
1668 Output_data_got
<got_size
, big_endian
>::do_write(Output_file
* of
)
1670 const int add
= got_size
/ 8;
1672 const off_t off
= this->offset();
1673 const off_t oview_size
= this->data_size();
1674 unsigned char* const oview
= of
->get_output_view(off
, oview_size
);
1676 unsigned char* pov
= oview
;
1677 for (unsigned int i
= 0; i
< this->entries_
.size(); ++i
)
1679 this->entries_
[i
].write(i
, pov
);
1683 gold_assert(pov
- oview
== oview_size
);
1685 of
->write_output_view(off
, oview_size
, oview
);
1687 // We no longer need the GOT entries.
1688 this->entries_
.clear();
1691 // Create a new GOT entry and return its offset.
1693 template<int got_size
, bool big_endian
>
1695 Output_data_got
<got_size
, big_endian
>::add_got_entry(Got_entry got_entry
)
1697 if (!this->is_data_size_valid())
1699 this->entries_
.push_back(got_entry
);
1700 this->set_got_size();
1701 return this->last_got_offset();
1705 // For an incremental update, find an available slot.
1706 off_t got_offset
= this->free_list_
.allocate(got_size
/ 8,
1708 if (got_offset
== -1)
1709 gold_fallback(_("out of patch space (GOT);"
1710 " relink with --incremental-full"));
1711 unsigned int got_index
= got_offset
/ (got_size
/ 8);
1712 gold_assert(got_index
< this->entries_
.size());
1713 this->entries_
[got_index
] = got_entry
;
1714 return static_cast<unsigned int>(got_offset
);
1718 // Create a pair of new GOT entries and return the offset of the first.
1720 template<int got_size
, bool big_endian
>
1722 Output_data_got
<got_size
, big_endian
>::add_got_entry_pair(
1723 Got_entry got_entry_1
,
1724 Got_entry got_entry_2
)
1726 if (!this->is_data_size_valid())
1728 unsigned int got_offset
;
1729 this->entries_
.push_back(got_entry_1
);
1730 got_offset
= this->last_got_offset();
1731 this->entries_
.push_back(got_entry_2
);
1732 this->set_got_size();
1737 // For an incremental update, find an available pair of slots.
1738 off_t got_offset
= this->free_list_
.allocate(2 * got_size
/ 8,
1740 if (got_offset
== -1)
1741 gold_fallback(_("out of patch space (GOT);"
1742 " relink with --incremental-full"));
1743 unsigned int got_index
= got_offset
/ (got_size
/ 8);
1744 gold_assert(got_index
< this->entries_
.size());
1745 this->entries_
[got_index
] = got_entry_1
;
1746 this->entries_
[got_index
+ 1] = got_entry_2
;
1747 return static_cast<unsigned int>(got_offset
);
1751 // Replace GOT entry I with a new value.
1753 template<int got_size
, bool big_endian
>
1755 Output_data_got
<got_size
, big_endian
>::replace_got_entry(
1757 Got_entry got_entry
)
1759 gold_assert(i
< this->entries_
.size());
1760 this->entries_
[i
] = got_entry
;
1763 // Output_data_dynamic::Dynamic_entry methods.
1765 // Write out the entry.
1767 template<int size
, bool big_endian
>
1769 Output_data_dynamic::Dynamic_entry::write(
1771 const Stringpool
* pool
) const
1773 typename
elfcpp::Elf_types
<size
>::Elf_WXword val
;
1774 switch (this->offset_
)
1776 case DYNAMIC_NUMBER
:
1780 case DYNAMIC_SECTION_SIZE
:
1781 val
= this->u_
.od
->data_size();
1782 if (this->od2
!= NULL
)
1783 val
+= this->od2
->data_size();
1786 case DYNAMIC_SYMBOL
:
1788 const Sized_symbol
<size
>* s
=
1789 static_cast<const Sized_symbol
<size
>*>(this->u_
.sym
);
1794 case DYNAMIC_STRING
:
1795 val
= pool
->get_offset(this->u_
.str
);
1799 val
= this->u_
.od
->address() + this->offset_
;
1803 elfcpp::Dyn_write
<size
, big_endian
> dw(pov
);
1804 dw
.put_d_tag(this->tag_
);
1808 // Output_data_dynamic methods.
1810 // Adjust the output section to set the entry size.
1813 Output_data_dynamic::do_adjust_output_section(Output_section
* os
)
1815 if (parameters
->target().get_size() == 32)
1816 os
->set_entsize(elfcpp::Elf_sizes
<32>::dyn_size
);
1817 else if (parameters
->target().get_size() == 64)
1818 os
->set_entsize(elfcpp::Elf_sizes
<64>::dyn_size
);
1823 // Set the final data size.
1826 Output_data_dynamic::set_final_data_size()
1828 // Add the terminating entry if it hasn't been added.
1829 // Because of relaxation, we can run this multiple times.
1830 if (this->entries_
.empty() || this->entries_
.back().tag() != elfcpp::DT_NULL
)
1832 int extra
= parameters
->options().spare_dynamic_tags();
1833 for (int i
= 0; i
< extra
; ++i
)
1834 this->add_constant(elfcpp::DT_NULL
, 0);
1835 this->add_constant(elfcpp::DT_NULL
, 0);
1839 if (parameters
->target().get_size() == 32)
1840 dyn_size
= elfcpp::Elf_sizes
<32>::dyn_size
;
1841 else if (parameters
->target().get_size() == 64)
1842 dyn_size
= elfcpp::Elf_sizes
<64>::dyn_size
;
1845 this->set_data_size(this->entries_
.size() * dyn_size
);
1848 // Write out the dynamic entries.
1851 Output_data_dynamic::do_write(Output_file
* of
)
1853 switch (parameters
->size_and_endianness())
1855 #ifdef HAVE_TARGET_32_LITTLE
1856 case Parameters::TARGET_32_LITTLE
:
1857 this->sized_write
<32, false>(of
);
1860 #ifdef HAVE_TARGET_32_BIG
1861 case Parameters::TARGET_32_BIG
:
1862 this->sized_write
<32, true>(of
);
1865 #ifdef HAVE_TARGET_64_LITTLE
1866 case Parameters::TARGET_64_LITTLE
:
1867 this->sized_write
<64, false>(of
);
1870 #ifdef HAVE_TARGET_64_BIG
1871 case Parameters::TARGET_64_BIG
:
1872 this->sized_write
<64, true>(of
);
1880 template<int size
, bool big_endian
>
1882 Output_data_dynamic::sized_write(Output_file
* of
)
1884 const int dyn_size
= elfcpp::Elf_sizes
<size
>::dyn_size
;
1886 const off_t offset
= this->offset();
1887 const off_t oview_size
= this->data_size();
1888 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
1890 unsigned char* pov
= oview
;
1891 for (typename
Dynamic_entries::const_iterator p
= this->entries_
.begin();
1892 p
!= this->entries_
.end();
1895 p
->write
<size
, big_endian
>(pov
, this->pool_
);
1899 gold_assert(pov
- oview
== oview_size
);
1901 of
->write_output_view(offset
, oview_size
, oview
);
1903 // We no longer need the dynamic entries.
1904 this->entries_
.clear();
1907 // Class Output_symtab_xindex.
1910 Output_symtab_xindex::do_write(Output_file
* of
)
1912 const off_t offset
= this->offset();
1913 const off_t oview_size
= this->data_size();
1914 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
1916 memset(oview
, 0, oview_size
);
1918 if (parameters
->target().is_big_endian())
1919 this->endian_do_write
<true>(oview
);
1921 this->endian_do_write
<false>(oview
);
1923 of
->write_output_view(offset
, oview_size
, oview
);
1925 // We no longer need the data.
1926 this->entries_
.clear();
1929 template<bool big_endian
>
1931 Output_symtab_xindex::endian_do_write(unsigned char* const oview
)
1933 for (Xindex_entries::const_iterator p
= this->entries_
.begin();
1934 p
!= this->entries_
.end();
1937 unsigned int symndx
= p
->first
;
1938 gold_assert(symndx
* 4 < this->data_size());
1939 elfcpp::Swap
<32, big_endian
>::writeval(oview
+ symndx
* 4, p
->second
);
1943 // Output_fill_debug_info methods.
1945 // Return the minimum size needed for a dummy compilation unit header.
1948 Output_fill_debug_info::do_minimum_hole_size() const
1950 // Compile unit header fields: unit_length, version, debug_abbrev_offset,
1952 const size_t len
= 4 + 2 + 4 + 1;
1953 // For type units, add type_signature, type_offset.
1954 if (this->is_debug_types_
)
1959 // Write a dummy compilation unit header to fill a hole in the
1960 // .debug_info or .debug_types section.
1963 Output_fill_debug_info::do_write(Output_file
* of
, off_t off
, size_t len
) const
1965 gold_debug(DEBUG_INCREMENTAL
, "fill_debug_info(%08lx, %08lx)",
1966 static_cast<long>(off
), static_cast<long>(len
));
1968 gold_assert(len
>= this->do_minimum_hole_size());
1970 unsigned char* const oview
= of
->get_output_view(off
, len
);
1971 unsigned char* pov
= oview
;
1973 // Write header fields: unit_length, version, debug_abbrev_offset,
1975 if (this->is_big_endian())
1977 elfcpp::Swap_unaligned
<32, true>::writeval(pov
, len
- 4);
1978 elfcpp::Swap_unaligned
<16, true>::writeval(pov
+ 4, this->version
);
1979 elfcpp::Swap_unaligned
<32, true>::writeval(pov
+ 6, 0);
1983 elfcpp::Swap_unaligned
<32, false>::writeval(pov
, len
- 4);
1984 elfcpp::Swap_unaligned
<16, false>::writeval(pov
+ 4, this->version
);
1985 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 6, 0);
1990 // For type units, the additional header fields -- type_signature,
1991 // type_offset -- can be filled with zeroes.
1993 // Fill the remainder of the free space with zeroes. The first
1994 // zero should tell the consumer there are no DIEs to read in this
1995 // compilation unit.
1996 if (pov
< oview
+ len
)
1997 memset(pov
, 0, oview
+ len
- pov
);
1999 of
->write_output_view(off
, len
, oview
);
2002 // Output_fill_debug_line methods.
2004 // Return the minimum size needed for a dummy line number program header.
2007 Output_fill_debug_line::do_minimum_hole_size() const
2009 // Line number program header fields: unit_length, version, header_length,
2010 // minimum_instruction_length, default_is_stmt, line_base, line_range,
2011 // opcode_base, standard_opcode_lengths[], include_directories, filenames.
2012 const size_t len
= 4 + 2 + 4 + this->header_length
;
2016 // Write a dummy line number program header to fill a hole in the
2017 // .debug_line section.
2020 Output_fill_debug_line::do_write(Output_file
* of
, off_t off
, size_t len
) const
2022 gold_debug(DEBUG_INCREMENTAL
, "fill_debug_line(%08lx, %08lx)",
2023 static_cast<long>(off
), static_cast<long>(len
));
2025 gold_assert(len
>= this->do_minimum_hole_size());
2027 unsigned char* const oview
= of
->get_output_view(off
, len
);
2028 unsigned char* pov
= oview
;
2030 // Write header fields: unit_length, version, header_length,
2031 // minimum_instruction_length, default_is_stmt, line_base, line_range,
2032 // opcode_base, standard_opcode_lengths[], include_directories, filenames.
2033 // We set the header_length field to cover the entire hole, so the
2034 // line number program is empty.
2035 if (this->is_big_endian())
2037 elfcpp::Swap_unaligned
<32, true>::writeval(pov
, len
- 4);
2038 elfcpp::Swap_unaligned
<16, true>::writeval(pov
+ 4, this->version
);
2039 elfcpp::Swap_unaligned
<32, true>::writeval(pov
+ 6, len
- (4 + 2 + 4));
2043 elfcpp::Swap_unaligned
<32, false>::writeval(pov
, len
- 4);
2044 elfcpp::Swap_unaligned
<16, false>::writeval(pov
+ 4, this->version
);
2045 elfcpp::Swap_unaligned
<32, false>::writeval(pov
+ 6, len
- (4 + 2 + 4));
2048 *pov
++ = 1; // minimum_instruction_length
2049 *pov
++ = 0; // default_is_stmt
2050 *pov
++ = 0; // line_base
2051 *pov
++ = 5; // line_range
2052 *pov
++ = 13; // opcode_base
2053 *pov
++ = 0; // standard_opcode_lengths[1]
2054 *pov
++ = 1; // standard_opcode_lengths[2]
2055 *pov
++ = 1; // standard_opcode_lengths[3]
2056 *pov
++ = 1; // standard_opcode_lengths[4]
2057 *pov
++ = 1; // standard_opcode_lengths[5]
2058 *pov
++ = 0; // standard_opcode_lengths[6]
2059 *pov
++ = 0; // standard_opcode_lengths[7]
2060 *pov
++ = 0; // standard_opcode_lengths[8]
2061 *pov
++ = 1; // standard_opcode_lengths[9]
2062 *pov
++ = 0; // standard_opcode_lengths[10]
2063 *pov
++ = 0; // standard_opcode_lengths[11]
2064 *pov
++ = 1; // standard_opcode_lengths[12]
2065 *pov
++ = 0; // include_directories (empty)
2066 *pov
++ = 0; // filenames (empty)
2068 // Some consumers don't check the header_length field, and simply
2069 // start reading the line number program immediately following the
2070 // header. For those consumers, we fill the remainder of the free
2071 // space with DW_LNS_set_basic_block opcodes. These are effectively
2072 // no-ops: the resulting line table program will not create any rows.
2073 if (pov
< oview
+ len
)
2074 memset(pov
, elfcpp::DW_LNS_set_basic_block
, oview
+ len
- pov
);
2076 of
->write_output_view(off
, len
, oview
);
2079 // Output_section::Input_section methods.
2081 // Return the current data size. For an input section we store the size here.
2082 // For an Output_section_data, we have to ask it for the size.
2085 Output_section::Input_section::current_data_size() const
2087 if (this->is_input_section())
2088 return this->u1_
.data_size
;
2091 this->u2_
.posd
->pre_finalize_data_size();
2092 return this->u2_
.posd
->current_data_size();
2096 // Return the data size. For an input section we store the size here.
2097 // For an Output_section_data, we have to ask it for the size.
2100 Output_section::Input_section::data_size() const
2102 if (this->is_input_section())
2103 return this->u1_
.data_size
;
2105 return this->u2_
.posd
->data_size();
2108 // Return the object for an input section.
2111 Output_section::Input_section::relobj() const
2113 if (this->is_input_section())
2114 return this->u2_
.object
;
2115 else if (this->is_merge_section())
2117 gold_assert(this->u2_
.pomb
->first_relobj() != NULL
);
2118 return this->u2_
.pomb
->first_relobj();
2120 else if (this->is_relaxed_input_section())
2121 return this->u2_
.poris
->relobj();
2126 // Return the input section index for an input section.
2129 Output_section::Input_section::shndx() const
2131 if (this->is_input_section())
2132 return this->shndx_
;
2133 else if (this->is_merge_section())
2135 gold_assert(this->u2_
.pomb
->first_relobj() != NULL
);
2136 return this->u2_
.pomb
->first_shndx();
2138 else if (this->is_relaxed_input_section())
2139 return this->u2_
.poris
->shndx();
2144 // Set the address and file offset.
2147 Output_section::Input_section::set_address_and_file_offset(
2150 off_t section_file_offset
)
2152 if (this->is_input_section())
2153 this->u2_
.object
->set_section_offset(this->shndx_
,
2154 file_offset
- section_file_offset
);
2156 this->u2_
.posd
->set_address_and_file_offset(address
, file_offset
);
2159 // Reset the address and file offset.
2162 Output_section::Input_section::reset_address_and_file_offset()
2164 if (!this->is_input_section())
2165 this->u2_
.posd
->reset_address_and_file_offset();
2168 // Finalize the data size.
2171 Output_section::Input_section::finalize_data_size()
2173 if (!this->is_input_section())
2174 this->u2_
.posd
->finalize_data_size();
2177 // Try to turn an input offset into an output offset. We want to
2178 // return the output offset relative to the start of this
2179 // Input_section in the output section.
2182 Output_section::Input_section::output_offset(
2183 const Relobj
* object
,
2185 section_offset_type offset
,
2186 section_offset_type
* poutput
) const
2188 if (!this->is_input_section())
2189 return this->u2_
.posd
->output_offset(object
, shndx
, offset
, poutput
);
2192 if (this->shndx_
!= shndx
|| this->u2_
.object
!= object
)
2199 // Return whether this is the merge section for the input section
2203 Output_section::Input_section::is_merge_section_for(const Relobj
* object
,
2204 unsigned int shndx
) const
2206 if (this->is_input_section())
2208 return this->u2_
.posd
->is_merge_section_for(object
, shndx
);
2211 // Write out the data. We don't have to do anything for an input
2212 // section--they are handled via Object::relocate--but this is where
2213 // we write out the data for an Output_section_data.
2216 Output_section::Input_section::write(Output_file
* of
)
2218 if (!this->is_input_section())
2219 this->u2_
.posd
->write(of
);
2222 // Write the data to a buffer. As for write(), we don't have to do
2223 // anything for an input section.
2226 Output_section::Input_section::write_to_buffer(unsigned char* buffer
)
2228 if (!this->is_input_section())
2229 this->u2_
.posd
->write_to_buffer(buffer
);
2232 // Print to a map file.
2235 Output_section::Input_section::print_to_mapfile(Mapfile
* mapfile
) const
2237 switch (this->shndx_
)
2239 case OUTPUT_SECTION_CODE
:
2240 case MERGE_DATA_SECTION_CODE
:
2241 case MERGE_STRING_SECTION_CODE
:
2242 this->u2_
.posd
->print_to_mapfile(mapfile
);
2245 case RELAXED_INPUT_SECTION_CODE
:
2247 Output_relaxed_input_section
* relaxed_section
=
2248 this->relaxed_input_section();
2249 mapfile
->print_input_section(relaxed_section
->relobj(),
2250 relaxed_section
->shndx());
2254 mapfile
->print_input_section(this->u2_
.object
, this->shndx_
);
2259 // Output_section methods.
2261 // Construct an Output_section. NAME will point into a Stringpool.
2263 Output_section::Output_section(const char* name
, elfcpp::Elf_Word type
,
2264 elfcpp::Elf_Xword flags
)
2269 link_section_(NULL
),
2271 info_section_(NULL
),
2276 order_(ORDER_INVALID
),
2281 first_input_offset_(0),
2283 postprocessing_buffer_(NULL
),
2284 needs_symtab_index_(false),
2285 needs_dynsym_index_(false),
2286 should_link_to_symtab_(false),
2287 should_link_to_dynsym_(false),
2288 after_input_sections_(false),
2289 requires_postprocessing_(false),
2290 found_in_sections_clause_(false),
2291 has_load_address_(false),
2292 info_uses_section_index_(false),
2293 input_section_order_specified_(false),
2294 may_sort_attached_input_sections_(false),
2295 must_sort_attached_input_sections_(false),
2296 attached_input_sections_are_sorted_(false),
2298 is_small_section_(false),
2299 is_large_section_(false),
2300 generate_code_fills_at_write_(false),
2301 is_entsize_zero_(false),
2302 section_offsets_need_adjustment_(false),
2304 always_keeps_input_sections_(false),
2305 has_fixed_layout_(false),
2306 is_patch_space_allowed_(false),
2307 is_unique_segment_(false),
2309 extra_segment_flags_(0),
2310 segment_alignment_(0),
2312 lookup_maps_(new Output_section_lookup_maps
),
2314 free_space_fill_(NULL
),
2317 // An unallocated section has no address. Forcing this means that
2318 // we don't need special treatment for symbols defined in debug
2320 if ((flags
& elfcpp::SHF_ALLOC
) == 0)
2321 this->set_address(0);
2324 Output_section::~Output_section()
2326 delete this->checkpoint_
;
2329 // Set the entry size.
2332 Output_section::set_entsize(uint64_t v
)
2334 if (this->is_entsize_zero_
)
2336 else if (this->entsize_
== 0)
2338 else if (this->entsize_
!= v
)
2341 this->is_entsize_zero_
= 1;
2345 // Add the input section SHNDX, with header SHDR, named SECNAME, in
2346 // OBJECT, to the Output_section. RELOC_SHNDX is the index of a
2347 // relocation section which applies to this section, or 0 if none, or
2348 // -1U if more than one. Return the offset of the input section
2349 // within the output section. Return -1 if the input section will
2350 // receive special handling. In the normal case we don't always keep
2351 // track of input sections for an Output_section. Instead, each
2352 // Object keeps track of the Output_section for each of its input
2353 // sections. However, if HAVE_SECTIONS_SCRIPT is true, we do keep
2354 // track of input sections here; this is used when SECTIONS appears in
2357 template<int size
, bool big_endian
>
2359 Output_section::add_input_section(Layout
* layout
,
2360 Sized_relobj_file
<size
, big_endian
>* object
,
2362 const char* secname
,
2363 const elfcpp::Shdr
<size
, big_endian
>& shdr
,
2364 unsigned int reloc_shndx
,
2365 bool have_sections_script
)
2367 elfcpp::Elf_Xword addralign
= shdr
.get_sh_addralign();
2368 if ((addralign
& (addralign
- 1)) != 0)
2370 object
->error(_("invalid alignment %lu for section \"%s\""),
2371 static_cast<unsigned long>(addralign
), secname
);
2375 if (addralign
> this->addralign_
)
2376 this->addralign_
= addralign
;
2378 typename
elfcpp::Elf_types
<size
>::Elf_WXword sh_flags
= shdr
.get_sh_flags();
2379 uint64_t entsize
= shdr
.get_sh_entsize();
2381 // .debug_str is a mergeable string section, but is not always so
2382 // marked by compilers. Mark manually here so we can optimize.
2383 if (strcmp(secname
, ".debug_str") == 0)
2385 sh_flags
|= (elfcpp::SHF_MERGE
| elfcpp::SHF_STRINGS
);
2389 this->update_flags_for_input_section(sh_flags
);
2390 this->set_entsize(entsize
);
2392 // If this is a SHF_MERGE section, we pass all the input sections to
2393 // a Output_data_merge. We don't try to handle relocations for such
2394 // a section. We don't try to handle empty merge sections--they
2395 // mess up the mappings, and are useless anyhow.
2396 // FIXME: Need to handle merge sections during incremental update.
2397 if ((sh_flags
& elfcpp::SHF_MERGE
) != 0
2399 && shdr
.get_sh_size() > 0
2400 && !parameters
->incremental())
2402 // Keep information about merged input sections for rebuilding fast
2403 // lookup maps if we have sections-script or we do relaxation.
2404 bool keeps_input_sections
= (this->always_keeps_input_sections_
2405 || have_sections_script
2406 || parameters
->target().may_relax());
2408 if (this->add_merge_input_section(object
, shndx
, sh_flags
, entsize
,
2409 addralign
, keeps_input_sections
))
2411 // Tell the relocation routines that they need to call the
2412 // output_offset method to determine the final address.
2417 section_size_type input_section_size
= shdr
.get_sh_size();
2418 section_size_type uncompressed_size
;
2419 if (object
->section_is_compressed(shndx
, &uncompressed_size
))
2420 input_section_size
= uncompressed_size
;
2422 off_t offset_in_section
;
2423 off_t aligned_offset_in_section
;
2424 if (this->has_fixed_layout())
2426 // For incremental updates, find a chunk of unused space in the section.
2427 offset_in_section
= this->free_list_
.allocate(input_section_size
,
2429 if (offset_in_section
== -1)
2430 gold_fallback(_("out of patch space in section %s; "
2431 "relink with --incremental-full"),
2433 aligned_offset_in_section
= offset_in_section
;
2437 offset_in_section
= this->current_data_size_for_child();
2438 aligned_offset_in_section
= align_address(offset_in_section
,
2440 this->set_current_data_size_for_child(aligned_offset_in_section
2441 + input_section_size
);
2444 // Determine if we want to delay code-fill generation until the output
2445 // section is written. When the target is relaxing, we want to delay fill
2446 // generating to avoid adjusting them during relaxation. Also, if we are
2447 // sorting input sections we must delay fill generation.
2448 if (!this->generate_code_fills_at_write_
2449 && !have_sections_script
2450 && (sh_flags
& elfcpp::SHF_EXECINSTR
) != 0
2451 && parameters
->target().has_code_fill()
2452 && (parameters
->target().may_relax()
2453 || layout
->is_section_ordering_specified()))
2455 gold_assert(this->fills_
.empty());
2456 this->generate_code_fills_at_write_
= true;
2459 if (aligned_offset_in_section
> offset_in_section
2460 && !this->generate_code_fills_at_write_
2461 && !have_sections_script
2462 && (sh_flags
& elfcpp::SHF_EXECINSTR
) != 0
2463 && parameters
->target().has_code_fill())
2465 // We need to add some fill data. Using fill_list_ when
2466 // possible is an optimization, since we will often have fill
2467 // sections without input sections.
2468 off_t fill_len
= aligned_offset_in_section
- offset_in_section
;
2469 if (this->input_sections_
.empty())
2470 this->fills_
.push_back(Fill(offset_in_section
, fill_len
));
2473 std::string
fill_data(parameters
->target().code_fill(fill_len
));
2474 Output_data_const
* odc
= new Output_data_const(fill_data
, 1);
2475 this->input_sections_
.push_back(Input_section(odc
));
2479 // We need to keep track of this section if we are already keeping
2480 // track of sections, or if we are relaxing. Also, if this is a
2481 // section which requires sorting, or which may require sorting in
2482 // the future, we keep track of the sections. If the
2483 // --section-ordering-file option is used to specify the order of
2484 // sections, we need to keep track of sections.
2485 if (this->always_keeps_input_sections_
2486 || have_sections_script
2487 || !this->input_sections_
.empty()
2488 || this->may_sort_attached_input_sections()
2489 || this->must_sort_attached_input_sections()
2490 || parameters
->options().user_set_Map()
2491 || parameters
->target().may_relax()
2492 || layout
->is_section_ordering_specified())
2494 Input_section
isecn(object
, shndx
, input_section_size
, addralign
);
2495 /* If section ordering is requested by specifying a ordering file,
2496 using --section-ordering-file, match the section name with
2498 if (parameters
->options().section_ordering_file())
2500 unsigned int section_order_index
=
2501 layout
->find_section_order_index(std::string(secname
));
2502 if (section_order_index
!= 0)
2504 isecn
.set_section_order_index(section_order_index
);
2505 this->set_input_section_order_specified();
2508 if (this->has_fixed_layout())
2510 // For incremental updates, finalize the address and offset now.
2511 uint64_t addr
= this->address();
2512 isecn
.set_address_and_file_offset(addr
+ aligned_offset_in_section
,
2513 aligned_offset_in_section
,
2516 this->input_sections_
.push_back(isecn
);
2519 return aligned_offset_in_section
;
2522 // Add arbitrary data to an output section.
2525 Output_section::add_output_section_data(Output_section_data
* posd
)
2527 Input_section
inp(posd
);
2528 this->add_output_section_data(&inp
);
2530 if (posd
->is_data_size_valid())
2532 off_t offset_in_section
;
2533 if (this->has_fixed_layout())
2535 // For incremental updates, find a chunk of unused space.
2536 offset_in_section
= this->free_list_
.allocate(posd
->data_size(),
2537 posd
->addralign(), 0);
2538 if (offset_in_section
== -1)
2539 gold_fallback(_("out of patch space in section %s; "
2540 "relink with --incremental-full"),
2542 // Finalize the address and offset now.
2543 uint64_t addr
= this->address();
2544 off_t offset
= this->offset();
2545 posd
->set_address_and_file_offset(addr
+ offset_in_section
,
2546 offset
+ offset_in_section
);
2550 offset_in_section
= this->current_data_size_for_child();
2551 off_t aligned_offset_in_section
= align_address(offset_in_section
,
2553 this->set_current_data_size_for_child(aligned_offset_in_section
2554 + posd
->data_size());
2557 else if (this->has_fixed_layout())
2559 // For incremental updates, arrange for the data to have a fixed layout.
2560 // This will mean that additions to the data must be allocated from
2561 // free space within the containing output section.
2562 uint64_t addr
= this->address();
2563 posd
->set_address(addr
);
2564 posd
->set_file_offset(0);
2565 // FIXME: This should eventually be unreachable.
2566 // gold_unreachable();
2570 // Add a relaxed input section.
2573 Output_section::add_relaxed_input_section(Layout
* layout
,
2574 Output_relaxed_input_section
* poris
,
2575 const std::string
& name
)
2577 Input_section
inp(poris
);
2579 // If the --section-ordering-file option is used to specify the order of
2580 // sections, we need to keep track of sections.
2581 if (layout
->is_section_ordering_specified())
2583 unsigned int section_order_index
=
2584 layout
->find_section_order_index(name
);
2585 if (section_order_index
!= 0)
2587 inp
.set_section_order_index(section_order_index
);
2588 this->set_input_section_order_specified();
2592 this->add_output_section_data(&inp
);
2593 if (this->lookup_maps_
->is_valid())
2594 this->lookup_maps_
->add_relaxed_input_section(poris
->relobj(),
2595 poris
->shndx(), poris
);
2597 // For a relaxed section, we use the current data size. Linker scripts
2598 // get all the input sections, including relaxed one from an output
2599 // section and add them back to the same output section to compute the
2600 // output section size. If we do not account for sizes of relaxed input
2601 // sections, an output section would be incorrectly sized.
2602 off_t offset_in_section
= this->current_data_size_for_child();
2603 off_t aligned_offset_in_section
= align_address(offset_in_section
,
2604 poris
->addralign());
2605 this->set_current_data_size_for_child(aligned_offset_in_section
2606 + poris
->current_data_size());
2609 // Add arbitrary data to an output section by Input_section.
2612 Output_section::add_output_section_data(Input_section
* inp
)
2614 if (this->input_sections_
.empty())
2615 this->first_input_offset_
= this->current_data_size_for_child();
2617 this->input_sections_
.push_back(*inp
);
2619 uint64_t addralign
= inp
->addralign();
2620 if (addralign
> this->addralign_
)
2621 this->addralign_
= addralign
;
2623 inp
->set_output_section(this);
2626 // Add a merge section to an output section.
2629 Output_section::add_output_merge_section(Output_section_data
* posd
,
2630 bool is_string
, uint64_t entsize
)
2632 Input_section
inp(posd
, is_string
, entsize
);
2633 this->add_output_section_data(&inp
);
2636 // Add an input section to a SHF_MERGE section.
2639 Output_section::add_merge_input_section(Relobj
* object
, unsigned int shndx
,
2640 uint64_t flags
, uint64_t entsize
,
2642 bool keeps_input_sections
)
2644 bool is_string
= (flags
& elfcpp::SHF_STRINGS
) != 0;
2646 // We only merge strings if the alignment is not more than the
2647 // character size. This could be handled, but it's unusual.
2648 if (is_string
&& addralign
> entsize
)
2651 // We cannot restore merged input section states.
2652 gold_assert(this->checkpoint_
== NULL
);
2654 // Look up merge sections by required properties.
2655 // Currently, we only invalidate the lookup maps in script processing
2656 // and relaxation. We should not have done either when we reach here.
2657 // So we assume that the lookup maps are valid to simply code.
2658 gold_assert(this->lookup_maps_
->is_valid());
2659 Merge_section_properties
msp(is_string
, entsize
, addralign
);
2660 Output_merge_base
* pomb
= this->lookup_maps_
->find_merge_section(msp
);
2661 bool is_new
= false;
2664 gold_assert(pomb
->is_string() == is_string
2665 && pomb
->entsize() == entsize
2666 && pomb
->addralign() == addralign
);
2670 // Create a new Output_merge_data or Output_merge_string_data.
2672 pomb
= new Output_merge_data(entsize
, addralign
);
2678 pomb
= new Output_merge_string
<char>(addralign
);
2681 pomb
= new Output_merge_string
<uint16_t>(addralign
);
2684 pomb
= new Output_merge_string
<uint32_t>(addralign
);
2690 // If we need to do script processing or relaxation, we need to keep
2691 // the original input sections to rebuild the fast lookup maps.
2692 if (keeps_input_sections
)
2693 pomb
->set_keeps_input_sections();
2697 if (pomb
->add_input_section(object
, shndx
))
2699 // Add new merge section to this output section and link merge
2700 // section properties to new merge section in map.
2703 this->add_output_merge_section(pomb
, is_string
, entsize
);
2704 this->lookup_maps_
->add_merge_section(msp
, pomb
);
2707 // Add input section to new merge section and link input section to new
2708 // merge section in map.
2709 this->lookup_maps_
->add_merge_input_section(object
, shndx
, pomb
);
2714 // If add_input_section failed, delete new merge section to avoid
2715 // exporting empty merge sections in Output_section::get_input_section.
2722 // Build a relaxation map to speed up relaxation of existing input sections.
2723 // Look up to the first LIMIT elements in INPUT_SECTIONS.
2726 Output_section::build_relaxation_map(
2727 const Input_section_list
& input_sections
,
2729 Relaxation_map
* relaxation_map
) const
2731 for (size_t i
= 0; i
< limit
; ++i
)
2733 const Input_section
& is(input_sections
[i
]);
2734 if (is
.is_input_section() || is
.is_relaxed_input_section())
2736 Section_id
sid(is
.relobj(), is
.shndx());
2737 (*relaxation_map
)[sid
] = i
;
2742 // Convert regular input sections in INPUT_SECTIONS into relaxed input
2743 // sections in RELAXED_SECTIONS. MAP is a prebuilt map from section id
2744 // indices of INPUT_SECTIONS.
2747 Output_section::convert_input_sections_in_list_to_relaxed_sections(
2748 const std::vector
<Output_relaxed_input_section
*>& relaxed_sections
,
2749 const Relaxation_map
& map
,
2750 Input_section_list
* input_sections
)
2752 for (size_t i
= 0; i
< relaxed_sections
.size(); ++i
)
2754 Output_relaxed_input_section
* poris
= relaxed_sections
[i
];
2755 Section_id
sid(poris
->relobj(), poris
->shndx());
2756 Relaxation_map::const_iterator p
= map
.find(sid
);
2757 gold_assert(p
!= map
.end());
2758 gold_assert((*input_sections
)[p
->second
].is_input_section());
2760 // Remember section order index of original input section
2761 // if it is set. Copy it to the relaxed input section.
2763 (*input_sections
)[p
->second
].section_order_index();
2764 (*input_sections
)[p
->second
] = Input_section(poris
);
2765 (*input_sections
)[p
->second
].set_section_order_index(soi
);
2769 // Convert regular input sections into relaxed input sections. RELAXED_SECTIONS
2770 // is a vector of pointers to Output_relaxed_input_section or its derived
2771 // classes. The relaxed sections must correspond to existing input sections.
2774 Output_section::convert_input_sections_to_relaxed_sections(
2775 const std::vector
<Output_relaxed_input_section
*>& relaxed_sections
)
2777 gold_assert(parameters
->target().may_relax());
2779 // We want to make sure that restore_states does not undo the effect of
2780 // this. If there is no checkpoint active, just search the current
2781 // input section list and replace the sections there. If there is
2782 // a checkpoint, also replace the sections there.
2784 // By default, we look at the whole list.
2785 size_t limit
= this->input_sections_
.size();
2787 if (this->checkpoint_
!= NULL
)
2789 // Replace input sections with relaxed input section in the saved
2790 // copy of the input section list.
2791 if (this->checkpoint_
->input_sections_saved())
2794 this->build_relaxation_map(
2795 *(this->checkpoint_
->input_sections()),
2796 this->checkpoint_
->input_sections()->size(),
2798 this->convert_input_sections_in_list_to_relaxed_sections(
2801 this->checkpoint_
->input_sections());
2805 // We have not copied the input section list yet. Instead, just
2806 // look at the portion that would be saved.
2807 limit
= this->checkpoint_
->input_sections_size();
2811 // Convert input sections in input_section_list.
2813 this->build_relaxation_map(this->input_sections_
, limit
, &map
);
2814 this->convert_input_sections_in_list_to_relaxed_sections(
2817 &this->input_sections_
);
2819 // Update fast look-up map.
2820 if (this->lookup_maps_
->is_valid())
2821 for (size_t i
= 0; i
< relaxed_sections
.size(); ++i
)
2823 Output_relaxed_input_section
* poris
= relaxed_sections
[i
];
2824 this->lookup_maps_
->add_relaxed_input_section(poris
->relobj(),
2825 poris
->shndx(), poris
);
2829 // Update the output section flags based on input section flags.
2832 Output_section::update_flags_for_input_section(elfcpp::Elf_Xword flags
)
2834 // If we created the section with SHF_ALLOC clear, we set the
2835 // address. If we are now setting the SHF_ALLOC flag, we need to
2837 if ((this->flags_
& elfcpp::SHF_ALLOC
) == 0
2838 && (flags
& elfcpp::SHF_ALLOC
) != 0)
2839 this->mark_address_invalid();
2841 this->flags_
|= (flags
2842 & (elfcpp::SHF_WRITE
2844 | elfcpp::SHF_EXECINSTR
));
2846 if ((flags
& elfcpp::SHF_MERGE
) == 0)
2847 this->flags_
&=~ elfcpp::SHF_MERGE
;
2850 if (this->current_data_size_for_child() == 0)
2851 this->flags_
|= elfcpp::SHF_MERGE
;
2854 if ((flags
& elfcpp::SHF_STRINGS
) == 0)
2855 this->flags_
&=~ elfcpp::SHF_STRINGS
;
2858 if (this->current_data_size_for_child() == 0)
2859 this->flags_
|= elfcpp::SHF_STRINGS
;
2863 // Find the merge section into which an input section with index SHNDX in
2864 // OBJECT has been added. Return NULL if none found.
2866 Output_section_data
*
2867 Output_section::find_merge_section(const Relobj
* object
,
2868 unsigned int shndx
) const
2870 if (!this->lookup_maps_
->is_valid())
2871 this->build_lookup_maps();
2872 return this->lookup_maps_
->find_merge_section(object
, shndx
);
2875 // Build the lookup maps for merge and relaxed sections. This is needs
2876 // to be declared as a const methods so that it is callable with a const
2877 // Output_section pointer. The method only updates states of the maps.
2880 Output_section::build_lookup_maps() const
2882 this->lookup_maps_
->clear();
2883 for (Input_section_list::const_iterator p
= this->input_sections_
.begin();
2884 p
!= this->input_sections_
.end();
2887 if (p
->is_merge_section())
2889 Output_merge_base
* pomb
= p
->output_merge_base();
2890 Merge_section_properties
msp(pomb
->is_string(), pomb
->entsize(),
2892 this->lookup_maps_
->add_merge_section(msp
, pomb
);
2893 for (Output_merge_base::Input_sections::const_iterator is
=
2894 pomb
->input_sections_begin();
2895 is
!= pomb
->input_sections_end();
2898 const Const_section_id
& csid
= *is
;
2899 this->lookup_maps_
->add_merge_input_section(csid
.first
,
2904 else if (p
->is_relaxed_input_section())
2906 Output_relaxed_input_section
* poris
= p
->relaxed_input_section();
2907 this->lookup_maps_
->add_relaxed_input_section(poris
->relobj(),
2908 poris
->shndx(), poris
);
2913 // Find an relaxed input section corresponding to an input section
2914 // in OBJECT with index SHNDX.
2916 const Output_relaxed_input_section
*
2917 Output_section::find_relaxed_input_section(const Relobj
* object
,
2918 unsigned int shndx
) const
2920 if (!this->lookup_maps_
->is_valid())
2921 this->build_lookup_maps();
2922 return this->lookup_maps_
->find_relaxed_input_section(object
, shndx
);
2925 // Given an address OFFSET relative to the start of input section
2926 // SHNDX in OBJECT, return whether this address is being included in
2927 // the final link. This should only be called if SHNDX in OBJECT has
2928 // a special mapping.
2931 Output_section::is_input_address_mapped(const Relobj
* object
,
2935 // Look at the Output_section_data_maps first.
2936 const Output_section_data
* posd
= this->find_merge_section(object
, shndx
);
2938 posd
= this->find_relaxed_input_section(object
, shndx
);
2942 section_offset_type output_offset
;
2943 bool found
= posd
->output_offset(object
, shndx
, offset
, &output_offset
);
2945 return output_offset
!= -1;
2948 // Fall back to the slow look-up.
2949 for (Input_section_list::const_iterator p
= this->input_sections_
.begin();
2950 p
!= this->input_sections_
.end();
2953 section_offset_type output_offset
;
2954 if (p
->output_offset(object
, shndx
, offset
, &output_offset
))
2955 return output_offset
!= -1;
2958 // By default we assume that the address is mapped. This should
2959 // only be called after we have passed all sections to Layout. At
2960 // that point we should know what we are discarding.
2964 // Given an address OFFSET relative to the start of input section
2965 // SHNDX in object OBJECT, return the output offset relative to the
2966 // start of the input section in the output section. This should only
2967 // be called if SHNDX in OBJECT has a special mapping.
2970 Output_section::output_offset(const Relobj
* object
, unsigned int shndx
,
2971 section_offset_type offset
) const
2973 // This can only be called meaningfully when we know the data size
2975 gold_assert(this->is_data_size_valid());
2977 // Look at the Output_section_data_maps first.
2978 const Output_section_data
* posd
= this->find_merge_section(object
, shndx
);
2980 posd
= this->find_relaxed_input_section(object
, shndx
);
2983 section_offset_type output_offset
;
2984 bool found
= posd
->output_offset(object
, shndx
, offset
, &output_offset
);
2986 return output_offset
;
2989 // Fall back to the slow look-up.
2990 for (Input_section_list::const_iterator p
= this->input_sections_
.begin();
2991 p
!= this->input_sections_
.end();
2994 section_offset_type output_offset
;
2995 if (p
->output_offset(object
, shndx
, offset
, &output_offset
))
2996 return output_offset
;
3001 // Return the output virtual address of OFFSET relative to the start
3002 // of input section SHNDX in object OBJECT.
3005 Output_section::output_address(const Relobj
* object
, unsigned int shndx
,
3008 uint64_t addr
= this->address() + this->first_input_offset_
;
3010 // Look at the Output_section_data_maps first.
3011 const Output_section_data
* posd
= this->find_merge_section(object
, shndx
);
3013 posd
= this->find_relaxed_input_section(object
, shndx
);
3014 if (posd
!= NULL
&& posd
->is_address_valid())
3016 section_offset_type output_offset
;
3017 bool found
= posd
->output_offset(object
, shndx
, offset
, &output_offset
);
3019 return posd
->address() + output_offset
;
3022 // Fall back to the slow look-up.
3023 for (Input_section_list::const_iterator p
= this->input_sections_
.begin();
3024 p
!= this->input_sections_
.end();
3027 addr
= align_address(addr
, p
->addralign());
3028 section_offset_type output_offset
;
3029 if (p
->output_offset(object
, shndx
, offset
, &output_offset
))
3031 if (output_offset
== -1)
3033 return addr
+ output_offset
;
3035 addr
+= p
->data_size();
3038 // If we get here, it means that we don't know the mapping for this
3039 // input section. This might happen in principle if
3040 // add_input_section were called before add_output_section_data.
3041 // But it should never actually happen.
3046 // Find the output address of the start of the merged section for
3047 // input section SHNDX in object OBJECT.
3050 Output_section::find_starting_output_address(const Relobj
* object
,
3052 uint64_t* paddr
) const
3054 // FIXME: This becomes a bottle-neck if we have many relaxed sections.
3055 // Looking up the merge section map does not always work as we sometimes
3056 // find a merge section without its address set.
3057 uint64_t addr
= this->address() + this->first_input_offset_
;
3058 for (Input_section_list::const_iterator p
= this->input_sections_
.begin();
3059 p
!= this->input_sections_
.end();
3062 addr
= align_address(addr
, p
->addralign());
3064 // It would be nice if we could use the existing output_offset
3065 // method to get the output offset of input offset 0.
3066 // Unfortunately we don't know for sure that input offset 0 is
3068 if (p
->is_merge_section_for(object
, shndx
))
3074 addr
+= p
->data_size();
3077 // We couldn't find a merge output section for this input section.
3081 // Update the data size of an Output_section.
3084 Output_section::update_data_size()
3086 if (this->input_sections_
.empty())
3089 if (this->must_sort_attached_input_sections()
3090 || this->input_section_order_specified())
3091 this->sort_attached_input_sections();
3093 off_t off
= this->first_input_offset_
;
3094 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3095 p
!= this->input_sections_
.end();
3098 off
= align_address(off
, p
->addralign());
3099 off
+= p
->current_data_size();
3102 this->set_current_data_size_for_child(off
);
3105 // Set the data size of an Output_section. This is where we handle
3106 // setting the addresses of any Output_section_data objects.
3109 Output_section::set_final_data_size()
3113 if (this->input_sections_
.empty())
3114 data_size
= this->current_data_size_for_child();
3117 if (this->must_sort_attached_input_sections()
3118 || this->input_section_order_specified())
3119 this->sort_attached_input_sections();
3121 uint64_t address
= this->address();
3122 off_t startoff
= this->offset();
3123 off_t off
= startoff
+ this->first_input_offset_
;
3124 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3125 p
!= this->input_sections_
.end();
3128 off
= align_address(off
, p
->addralign());
3129 p
->set_address_and_file_offset(address
+ (off
- startoff
), off
,
3131 off
+= p
->data_size();
3133 data_size
= off
- startoff
;
3136 // For full incremental links, we want to allocate some patch space
3137 // in most sections for subsequent incremental updates.
3138 if (this->is_patch_space_allowed_
&& parameters
->incremental_full())
3140 double pct
= parameters
->options().incremental_patch();
3141 size_t extra
= static_cast<size_t>(data_size
* pct
);
3142 if (this->free_space_fill_
!= NULL
3143 && this->free_space_fill_
->minimum_hole_size() > extra
)
3144 extra
= this->free_space_fill_
->minimum_hole_size();
3145 off_t new_size
= align_address(data_size
+ extra
, this->addralign());
3146 this->patch_space_
= new_size
- data_size
;
3147 gold_debug(DEBUG_INCREMENTAL
,
3148 "set_final_data_size: %08lx + %08lx: section %s",
3149 static_cast<long>(data_size
),
3150 static_cast<long>(this->patch_space_
),
3152 data_size
= new_size
;
3155 this->set_data_size(data_size
);
3158 // Reset the address and file offset.
3161 Output_section::do_reset_address_and_file_offset()
3163 // An unallocated section has no address. Forcing this means that
3164 // we don't need special treatment for symbols defined in debug
3165 // sections. We do the same in the constructor. This does not
3166 // apply to NOLOAD sections though.
3167 if (((this->flags_
& elfcpp::SHF_ALLOC
) == 0) && !this->is_noload_
)
3168 this->set_address(0);
3170 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3171 p
!= this->input_sections_
.end();
3173 p
->reset_address_and_file_offset();
3175 // Remove any patch space that was added in set_final_data_size.
3176 if (this->patch_space_
> 0)
3178 this->set_current_data_size_for_child(this->current_data_size_for_child()
3179 - this->patch_space_
);
3180 this->patch_space_
= 0;
3184 // Return true if address and file offset have the values after reset.
3187 Output_section::do_address_and_file_offset_have_reset_values() const
3189 if (this->is_offset_valid())
3192 // An unallocated section has address 0 after its construction or a reset.
3193 if ((this->flags_
& elfcpp::SHF_ALLOC
) == 0)
3194 return this->is_address_valid() && this->address() == 0;
3196 return !this->is_address_valid();
3199 // Set the TLS offset. Called only for SHT_TLS sections.
3202 Output_section::do_set_tls_offset(uint64_t tls_base
)
3204 this->tls_offset_
= this->address() - tls_base
;
3207 // In a few cases we need to sort the input sections attached to an
3208 // output section. This is used to implement the type of constructor
3209 // priority ordering implemented by the GNU linker, in which the
3210 // priority becomes part of the section name and the sections are
3211 // sorted by name. We only do this for an output section if we see an
3212 // attached input section matching ".ctors.*", ".dtors.*",
3213 // ".init_array.*" or ".fini_array.*".
3215 class Output_section::Input_section_sort_entry
3218 Input_section_sort_entry()
3219 : input_section_(), index_(-1U), section_has_name_(false),
3223 Input_section_sort_entry(const Input_section
& input_section
,
3225 bool must_sort_attached_input_sections
)
3226 : input_section_(input_section
), index_(index
),
3227 section_has_name_(input_section
.is_input_section()
3228 || input_section
.is_relaxed_input_section())
3230 if (this->section_has_name_
3231 && must_sort_attached_input_sections
)
3233 // This is only called single-threaded from Layout::finalize,
3234 // so it is OK to lock. Unfortunately we have no way to pass
3236 const Task
* dummy_task
= reinterpret_cast<const Task
*>(-1);
3237 Object
* obj
= (input_section
.is_input_section()
3238 ? input_section
.relobj()
3239 : input_section
.relaxed_input_section()->relobj());
3240 Task_lock_obj
<Object
> tl(dummy_task
, obj
);
3242 // This is a slow operation, which should be cached in
3243 // Layout::layout if this becomes a speed problem.
3244 this->section_name_
= obj
->section_name(input_section
.shndx());
3248 // Return the Input_section.
3249 const Input_section
&
3250 input_section() const
3252 gold_assert(this->index_
!= -1U);
3253 return this->input_section_
;
3256 // The index of this entry in the original list. This is used to
3257 // make the sort stable.
3261 gold_assert(this->index_
!= -1U);
3262 return this->index_
;
3265 // Whether there is a section name.
3267 section_has_name() const
3268 { return this->section_has_name_
; }
3270 // The section name.
3272 section_name() const
3274 gold_assert(this->section_has_name_
);
3275 return this->section_name_
;
3278 // Return true if the section name has a priority. This is assumed
3279 // to be true if it has a dot after the initial dot.
3281 has_priority() const
3283 gold_assert(this->section_has_name_
);
3284 return this->section_name_
.find('.', 1) != std::string::npos
;
3287 // Return the priority. Believe it or not, gcc encodes the priority
3288 // differently for .ctors/.dtors and .init_array/.fini_array
3291 get_priority() const
3293 gold_assert(this->section_has_name_
);
3295 if (is_prefix_of(".ctors.", this->section_name_
.c_str())
3296 || is_prefix_of(".dtors.", this->section_name_
.c_str()))
3298 else if (is_prefix_of(".init_array.", this->section_name_
.c_str())
3299 || is_prefix_of(".fini_array.", this->section_name_
.c_str()))
3304 unsigned long prio
= strtoul((this->section_name_
.c_str()
3305 + (is_ctors
? 7 : 12)),
3310 return 65535 - prio
;
3315 // Return true if this an input file whose base name matches
3316 // FILE_NAME. The base name must have an extension of ".o", and
3317 // must be exactly FILE_NAME.o or FILE_NAME, one character, ".o".
3318 // This is to match crtbegin.o as well as crtbeginS.o without
3319 // getting confused by other possibilities. Overall matching the
3320 // file name this way is a dreadful hack, but the GNU linker does it
3321 // in order to better support gcc, and we need to be compatible.
3323 match_file_name(const char* file_name
) const
3324 { return Layout::match_file_name(this->input_section_
.relobj(), file_name
); }
3326 // Returns 1 if THIS should appear before S in section order, -1 if S
3327 // appears before THIS and 0 if they are not comparable.
3329 compare_section_ordering(const Input_section_sort_entry
& s
) const
3331 unsigned int this_secn_index
= this->input_section_
.section_order_index();
3332 unsigned int s_secn_index
= s
.input_section().section_order_index();
3333 if (this_secn_index
> 0 && s_secn_index
> 0)
3335 if (this_secn_index
< s_secn_index
)
3337 else if (this_secn_index
> s_secn_index
)
3344 // The Input_section we are sorting.
3345 Input_section input_section_
;
3346 // The index of this Input_section in the original list.
3347 unsigned int index_
;
3348 // Whether this Input_section has a section name--it won't if this
3349 // is some random Output_section_data.
3350 bool section_has_name_
;
3351 // The section name if there is one.
3352 std::string section_name_
;
3355 // Return true if S1 should come before S2 in the output section.
3358 Output_section::Input_section_sort_compare::operator()(
3359 const Output_section::Input_section_sort_entry
& s1
,
3360 const Output_section::Input_section_sort_entry
& s2
) const
3362 // crtbegin.o must come first.
3363 bool s1_begin
= s1
.match_file_name("crtbegin");
3364 bool s2_begin
= s2
.match_file_name("crtbegin");
3365 if (s1_begin
|| s2_begin
)
3371 return s1
.index() < s2
.index();
3374 // crtend.o must come last.
3375 bool s1_end
= s1
.match_file_name("crtend");
3376 bool s2_end
= s2
.match_file_name("crtend");
3377 if (s1_end
|| s2_end
)
3383 return s1
.index() < s2
.index();
3386 // We sort all the sections with no names to the end.
3387 if (!s1
.section_has_name() || !s2
.section_has_name())
3389 if (s1
.section_has_name())
3391 if (s2
.section_has_name())
3393 return s1
.index() < s2
.index();
3396 // A section with a priority follows a section without a priority.
3397 bool s1_has_priority
= s1
.has_priority();
3398 bool s2_has_priority
= s2
.has_priority();
3399 if (s1_has_priority
&& !s2_has_priority
)
3401 if (!s1_has_priority
&& s2_has_priority
)
3404 // Check if a section order exists for these sections through a section
3405 // ordering file. If sequence_num is 0, an order does not exist.
3406 int sequence_num
= s1
.compare_section_ordering(s2
);
3407 if (sequence_num
!= 0)
3408 return sequence_num
== 1;
3410 // Otherwise we sort by name.
3411 int compare
= s1
.section_name().compare(s2
.section_name());
3415 // Otherwise we keep the input order.
3416 return s1
.index() < s2
.index();
3419 // Return true if S1 should come before S2 in an .init_array or .fini_array
3423 Output_section::Input_section_sort_init_fini_compare::operator()(
3424 const Output_section::Input_section_sort_entry
& s1
,
3425 const Output_section::Input_section_sort_entry
& s2
) const
3427 // We sort all the sections with no names to the end.
3428 if (!s1
.section_has_name() || !s2
.section_has_name())
3430 if (s1
.section_has_name())
3432 if (s2
.section_has_name())
3434 return s1
.index() < s2
.index();
3437 // A section without a priority follows a section with a priority.
3438 // This is the reverse of .ctors and .dtors sections.
3439 bool s1_has_priority
= s1
.has_priority();
3440 bool s2_has_priority
= s2
.has_priority();
3441 if (s1_has_priority
&& !s2_has_priority
)
3443 if (!s1_has_priority
&& s2_has_priority
)
3446 // .ctors and .dtors sections without priority come after
3447 // .init_array and .fini_array sections without priority.
3448 if (!s1_has_priority
3449 && (s1
.section_name() == ".ctors" || s1
.section_name() == ".dtors")
3450 && s1
.section_name() != s2
.section_name())
3452 if (!s2_has_priority
3453 && (s2
.section_name() == ".ctors" || s2
.section_name() == ".dtors")
3454 && s2
.section_name() != s1
.section_name())
3457 // Sort by priority if we can.
3458 if (s1_has_priority
)
3460 unsigned int s1_prio
= s1
.get_priority();
3461 unsigned int s2_prio
= s2
.get_priority();
3462 if (s1_prio
< s2_prio
)
3464 else if (s1_prio
> s2_prio
)
3468 // Check if a section order exists for these sections through a section
3469 // ordering file. If sequence_num is 0, an order does not exist.
3470 int sequence_num
= s1
.compare_section_ordering(s2
);
3471 if (sequence_num
!= 0)
3472 return sequence_num
== 1;
3474 // Otherwise we sort by name.
3475 int compare
= s1
.section_name().compare(s2
.section_name());
3479 // Otherwise we keep the input order.
3480 return s1
.index() < s2
.index();
3483 // Return true if S1 should come before S2. Sections that do not match
3484 // any pattern in the section ordering file are placed ahead of the sections
3485 // that match some pattern.
3488 Output_section::Input_section_sort_section_order_index_compare::operator()(
3489 const Output_section::Input_section_sort_entry
& s1
,
3490 const Output_section::Input_section_sort_entry
& s2
) const
3492 unsigned int s1_secn_index
= s1
.input_section().section_order_index();
3493 unsigned int s2_secn_index
= s2
.input_section().section_order_index();
3495 // Keep input order if section ordering cannot determine order.
3496 if (s1_secn_index
== s2_secn_index
)
3497 return s1
.index() < s2
.index();
3499 return s1_secn_index
< s2_secn_index
;
3502 // This updates the section order index of input sections according to the
3503 // the order specified in the mapping from Section id to order index.
3506 Output_section::update_section_layout(
3507 const Section_layout_order
* order_map
)
3509 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3510 p
!= this->input_sections_
.end();
3513 if (p
->is_input_section()
3514 || p
->is_relaxed_input_section())
3516 Object
* obj
= (p
->is_input_section()
3518 : p
->relaxed_input_section()->relobj());
3519 unsigned int shndx
= p
->shndx();
3520 Section_layout_order::const_iterator it
3521 = order_map
->find(Section_id(obj
, shndx
));
3522 if (it
== order_map
->end())
3524 unsigned int section_order_index
= it
->second
;
3525 if (section_order_index
!= 0)
3527 p
->set_section_order_index(section_order_index
);
3528 this->set_input_section_order_specified();
3534 // Sort the input sections attached to an output section.
3537 Output_section::sort_attached_input_sections()
3539 if (this->attached_input_sections_are_sorted_
)
3542 if (this->checkpoint_
!= NULL
3543 && !this->checkpoint_
->input_sections_saved())
3544 this->checkpoint_
->save_input_sections();
3546 // The only thing we know about an input section is the object and
3547 // the section index. We need the section name. Recomputing this
3548 // is slow but this is an unusual case. If this becomes a speed
3549 // problem we can cache the names as required in Layout::layout.
3551 // We start by building a larger vector holding a copy of each
3552 // Input_section, plus its current index in the list and its name.
3553 std::vector
<Input_section_sort_entry
> sort_list
;
3556 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3557 p
!= this->input_sections_
.end();
3559 sort_list
.push_back(Input_section_sort_entry(*p
, i
,
3560 this->must_sort_attached_input_sections()));
3562 // Sort the input sections.
3563 if (this->must_sort_attached_input_sections())
3565 if (this->type() == elfcpp::SHT_PREINIT_ARRAY
3566 || this->type() == elfcpp::SHT_INIT_ARRAY
3567 || this->type() == elfcpp::SHT_FINI_ARRAY
)
3568 std::sort(sort_list
.begin(), sort_list
.end(),
3569 Input_section_sort_init_fini_compare());
3571 std::sort(sort_list
.begin(), sort_list
.end(),
3572 Input_section_sort_compare());
3576 gold_assert(this->input_section_order_specified());
3577 std::sort(sort_list
.begin(), sort_list
.end(),
3578 Input_section_sort_section_order_index_compare());
3581 // Copy the sorted input sections back to our list.
3582 this->input_sections_
.clear();
3583 for (std::vector
<Input_section_sort_entry
>::iterator p
= sort_list
.begin();
3584 p
!= sort_list
.end();
3586 this->input_sections_
.push_back(p
->input_section());
3589 // Remember that we sorted the input sections, since we might get
3591 this->attached_input_sections_are_sorted_
= true;
3594 // Write the section header to *OSHDR.
3596 template<int size
, bool big_endian
>
3598 Output_section::write_header(const Layout
* layout
,
3599 const Stringpool
* secnamepool
,
3600 elfcpp::Shdr_write
<size
, big_endian
>* oshdr
) const
3602 oshdr
->put_sh_name(secnamepool
->get_offset(this->name_
));
3603 oshdr
->put_sh_type(this->type_
);
3605 elfcpp::Elf_Xword flags
= this->flags_
;
3606 if (this->info_section_
!= NULL
&& this->info_uses_section_index_
)
3607 flags
|= elfcpp::SHF_INFO_LINK
;
3608 oshdr
->put_sh_flags(flags
);
3610 oshdr
->put_sh_addr(this->address());
3611 oshdr
->put_sh_offset(this->offset());
3612 oshdr
->put_sh_size(this->data_size());
3613 if (this->link_section_
!= NULL
)
3614 oshdr
->put_sh_link(this->link_section_
->out_shndx());
3615 else if (this->should_link_to_symtab_
)
3616 oshdr
->put_sh_link(layout
->symtab_section_shndx());
3617 else if (this->should_link_to_dynsym_
)
3618 oshdr
->put_sh_link(layout
->dynsym_section()->out_shndx());
3620 oshdr
->put_sh_link(this->link_
);
3622 elfcpp::Elf_Word info
;
3623 if (this->info_section_
!= NULL
)
3625 if (this->info_uses_section_index_
)
3626 info
= this->info_section_
->out_shndx();
3628 info
= this->info_section_
->symtab_index();
3630 else if (this->info_symndx_
!= NULL
)
3631 info
= this->info_symndx_
->symtab_index();
3634 oshdr
->put_sh_info(info
);
3636 oshdr
->put_sh_addralign(this->addralign_
);
3637 oshdr
->put_sh_entsize(this->entsize_
);
3640 // Write out the data. For input sections the data is written out by
3641 // Object::relocate, but we have to handle Output_section_data objects
3645 Output_section::do_write(Output_file
* of
)
3647 gold_assert(!this->requires_postprocessing());
3649 // If the target performs relaxation, we delay filler generation until now.
3650 gold_assert(!this->generate_code_fills_at_write_
|| this->fills_
.empty());
3652 off_t output_section_file_offset
= this->offset();
3653 for (Fill_list::iterator p
= this->fills_
.begin();
3654 p
!= this->fills_
.end();
3657 std::string
fill_data(parameters
->target().code_fill(p
->length()));
3658 of
->write(output_section_file_offset
+ p
->section_offset(),
3659 fill_data
.data(), fill_data
.size());
3662 off_t off
= this->offset() + this->first_input_offset_
;
3663 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3664 p
!= this->input_sections_
.end();
3667 off_t aligned_off
= align_address(off
, p
->addralign());
3668 if (this->generate_code_fills_at_write_
&& (off
!= aligned_off
))
3670 size_t fill_len
= aligned_off
- off
;
3671 std::string
fill_data(parameters
->target().code_fill(fill_len
));
3672 of
->write(off
, fill_data
.data(), fill_data
.size());
3676 off
= aligned_off
+ p
->data_size();
3679 // For incremental links, fill in unused chunks in debug sections
3680 // with dummy compilation unit headers.
3681 if (this->free_space_fill_
!= NULL
)
3683 for (Free_list::Const_iterator p
= this->free_list_
.begin();
3684 p
!= this->free_list_
.end();
3687 off_t off
= p
->start_
;
3688 size_t len
= p
->end_
- off
;
3689 this->free_space_fill_
->write(of
, this->offset() + off
, len
);
3691 if (this->patch_space_
> 0)
3693 off_t off
= this->current_data_size_for_child() - this->patch_space_
;
3694 this->free_space_fill_
->write(of
, this->offset() + off
,
3695 this->patch_space_
);
3700 // If a section requires postprocessing, create the buffer to use.
3703 Output_section::create_postprocessing_buffer()
3705 gold_assert(this->requires_postprocessing());
3707 if (this->postprocessing_buffer_
!= NULL
)
3710 if (!this->input_sections_
.empty())
3712 off_t off
= this->first_input_offset_
;
3713 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3714 p
!= this->input_sections_
.end();
3717 off
= align_address(off
, p
->addralign());
3718 p
->finalize_data_size();
3719 off
+= p
->data_size();
3721 this->set_current_data_size_for_child(off
);
3724 off_t buffer_size
= this->current_data_size_for_child();
3725 this->postprocessing_buffer_
= new unsigned char[buffer_size
];
3728 // Write all the data of an Output_section into the postprocessing
3729 // buffer. This is used for sections which require postprocessing,
3730 // such as compression. Input sections are handled by
3731 // Object::Relocate.
3734 Output_section::write_to_postprocessing_buffer()
3736 gold_assert(this->requires_postprocessing());
3738 // If the target performs relaxation, we delay filler generation until now.
3739 gold_assert(!this->generate_code_fills_at_write_
|| this->fills_
.empty());
3741 unsigned char* buffer
= this->postprocessing_buffer();
3742 for (Fill_list::iterator p
= this->fills_
.begin();
3743 p
!= this->fills_
.end();
3746 std::string
fill_data(parameters
->target().code_fill(p
->length()));
3747 memcpy(buffer
+ p
->section_offset(), fill_data
.data(),
3751 off_t off
= this->first_input_offset_
;
3752 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3753 p
!= this->input_sections_
.end();
3756 off_t aligned_off
= align_address(off
, p
->addralign());
3757 if (this->generate_code_fills_at_write_
&& (off
!= aligned_off
))
3759 size_t fill_len
= aligned_off
- off
;
3760 std::string
fill_data(parameters
->target().code_fill(fill_len
));
3761 memcpy(buffer
+ off
, fill_data
.data(), fill_data
.size());
3764 p
->write_to_buffer(buffer
+ aligned_off
);
3765 off
= aligned_off
+ p
->data_size();
3769 // Get the input sections for linker script processing. We leave
3770 // behind the Output_section_data entries. Note that this may be
3771 // slightly incorrect for merge sections. We will leave them behind,
3772 // but it is possible that the script says that they should follow
3773 // some other input sections, as in:
3774 // .rodata { *(.rodata) *(.rodata.cst*) }
3775 // For that matter, we don't handle this correctly:
3776 // .rodata { foo.o(.rodata.cst*) *(.rodata.cst*) }
3777 // With luck this will never matter.
3780 Output_section::get_input_sections(
3782 const std::string
& fill
,
3783 std::list
<Input_section
>* input_sections
)
3785 if (this->checkpoint_
!= NULL
3786 && !this->checkpoint_
->input_sections_saved())
3787 this->checkpoint_
->save_input_sections();
3789 // Invalidate fast look-up maps.
3790 this->lookup_maps_
->invalidate();
3792 uint64_t orig_address
= address
;
3794 address
= align_address(address
, this->addralign());
3796 Input_section_list remaining
;
3797 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3798 p
!= this->input_sections_
.end();
3801 if (p
->is_input_section()
3802 || p
->is_relaxed_input_section()
3803 || p
->is_merge_section())
3804 input_sections
->push_back(*p
);
3807 uint64_t aligned_address
= align_address(address
, p
->addralign());
3808 if (aligned_address
!= address
&& !fill
.empty())
3810 section_size_type length
=
3811 convert_to_section_size_type(aligned_address
- address
);
3812 std::string this_fill
;
3813 this_fill
.reserve(length
);
3814 while (this_fill
.length() + fill
.length() <= length
)
3816 if (this_fill
.length() < length
)
3817 this_fill
.append(fill
, 0, length
- this_fill
.length());
3819 Output_section_data
* posd
= new Output_data_const(this_fill
, 0);
3820 remaining
.push_back(Input_section(posd
));
3822 address
= aligned_address
;
3824 remaining
.push_back(*p
);
3826 p
->finalize_data_size();
3827 address
+= p
->data_size();
3831 this->input_sections_
.swap(remaining
);
3832 this->first_input_offset_
= 0;
3834 uint64_t data_size
= address
- orig_address
;
3835 this->set_current_data_size_for_child(data_size
);
3839 // Add a script input section. SIS is an Output_section::Input_section,
3840 // which can be either a plain input section or a special input section like
3841 // a relaxed input section. For a special input section, its size must be
3845 Output_section::add_script_input_section(const Input_section
& sis
)
3847 uint64_t data_size
= sis
.data_size();
3848 uint64_t addralign
= sis
.addralign();
3849 if (addralign
> this->addralign_
)
3850 this->addralign_
= addralign
;
3852 off_t offset_in_section
= this->current_data_size_for_child();
3853 off_t aligned_offset_in_section
= align_address(offset_in_section
,
3856 this->set_current_data_size_for_child(aligned_offset_in_section
3859 this->input_sections_
.push_back(sis
);
3861 // Update fast lookup maps if necessary.
3862 if (this->lookup_maps_
->is_valid())
3864 if (sis
.is_merge_section())
3866 Output_merge_base
* pomb
= sis
.output_merge_base();
3867 Merge_section_properties
msp(pomb
->is_string(), pomb
->entsize(),
3869 this->lookup_maps_
->add_merge_section(msp
, pomb
);
3870 for (Output_merge_base::Input_sections::const_iterator p
=
3871 pomb
->input_sections_begin();
3872 p
!= pomb
->input_sections_end();
3874 this->lookup_maps_
->add_merge_input_section(p
->first
, p
->second
,
3877 else if (sis
.is_relaxed_input_section())
3879 Output_relaxed_input_section
* poris
= sis
.relaxed_input_section();
3880 this->lookup_maps_
->add_relaxed_input_section(poris
->relobj(),
3881 poris
->shndx(), poris
);
3886 // Save states for relaxation.
3889 Output_section::save_states()
3891 gold_assert(this->checkpoint_
== NULL
);
3892 Checkpoint_output_section
* checkpoint
=
3893 new Checkpoint_output_section(this->addralign_
, this->flags_
,
3894 this->input_sections_
,
3895 this->first_input_offset_
,
3896 this->attached_input_sections_are_sorted_
);
3897 this->checkpoint_
= checkpoint
;
3898 gold_assert(this->fills_
.empty());
3902 Output_section::discard_states()
3904 gold_assert(this->checkpoint_
!= NULL
);
3905 delete this->checkpoint_
;
3906 this->checkpoint_
= NULL
;
3907 gold_assert(this->fills_
.empty());
3909 // Simply invalidate the fast lookup maps since we do not keep
3911 this->lookup_maps_
->invalidate();
3915 Output_section::restore_states()
3917 gold_assert(this->checkpoint_
!= NULL
);
3918 Checkpoint_output_section
* checkpoint
= this->checkpoint_
;
3920 this->addralign_
= checkpoint
->addralign();
3921 this->flags_
= checkpoint
->flags();
3922 this->first_input_offset_
= checkpoint
->first_input_offset();
3924 if (!checkpoint
->input_sections_saved())
3926 // If we have not copied the input sections, just resize it.
3927 size_t old_size
= checkpoint
->input_sections_size();
3928 gold_assert(this->input_sections_
.size() >= old_size
);
3929 this->input_sections_
.resize(old_size
);
3933 // We need to copy the whole list. This is not efficient for
3934 // extremely large output with hundreads of thousands of input
3935 // objects. We may need to re-think how we should pass sections
3937 this->input_sections_
= *checkpoint
->input_sections();
3940 this->attached_input_sections_are_sorted_
=
3941 checkpoint
->attached_input_sections_are_sorted();
3943 // Simply invalidate the fast lookup maps since we do not keep
3945 this->lookup_maps_
->invalidate();
3948 // Update the section offsets of input sections in this. This is required if
3949 // relaxation causes some input sections to change sizes.
3952 Output_section::adjust_section_offsets()
3954 if (!this->section_offsets_need_adjustment_
)
3958 for (Input_section_list::iterator p
= this->input_sections_
.begin();
3959 p
!= this->input_sections_
.end();
3962 off
= align_address(off
, p
->addralign());
3963 if (p
->is_input_section())
3964 p
->relobj()->set_section_offset(p
->shndx(), off
);
3965 off
+= p
->data_size();
3968 this->section_offsets_need_adjustment_
= false;
3971 // Print to the map file.
3974 Output_section::do_print_to_mapfile(Mapfile
* mapfile
) const
3976 mapfile
->print_output_section(this);
3978 for (Input_section_list::const_iterator p
= this->input_sections_
.begin();
3979 p
!= this->input_sections_
.end();
3981 p
->print_to_mapfile(mapfile
);
3984 // Print stats for merge sections to stderr.
3987 Output_section::print_merge_stats()
3989 Input_section_list::iterator p
;
3990 for (p
= this->input_sections_
.begin();
3991 p
!= this->input_sections_
.end();
3993 p
->print_merge_stats(this->name_
);
3996 // Set a fixed layout for the section. Used for incremental update links.
3999 Output_section::set_fixed_layout(uint64_t sh_addr
, off_t sh_offset
,
4000 off_t sh_size
, uint64_t sh_addralign
)
4002 this->addralign_
= sh_addralign
;
4003 this->set_current_data_size(sh_size
);
4004 if ((this->flags_
& elfcpp::SHF_ALLOC
) != 0)
4005 this->set_address(sh_addr
);
4006 this->set_file_offset(sh_offset
);
4007 this->finalize_data_size();
4008 this->free_list_
.init(sh_size
, false);
4009 this->has_fixed_layout_
= true;
4012 // Reserve space within the fixed layout for the section. Used for
4013 // incremental update links.
4016 Output_section::reserve(uint64_t sh_offset
, uint64_t sh_size
)
4018 this->free_list_
.remove(sh_offset
, sh_offset
+ sh_size
);
4021 // Allocate space from the free list for the section. Used for
4022 // incremental update links.
4025 Output_section::allocate(off_t len
, uint64_t addralign
)
4027 return this->free_list_
.allocate(len
, addralign
, 0);
4030 // Output segment methods.
4032 Output_segment::Output_segment(elfcpp::Elf_Word type
, elfcpp::Elf_Word flags
)
4042 is_max_align_known_(false),
4043 are_addresses_set_(false),
4044 is_large_data_segment_(false),
4045 is_unique_segment_(false)
4047 // The ELF ABI specifies that a PT_TLS segment always has PF_R as
4049 if (type
== elfcpp::PT_TLS
)
4050 this->flags_
= elfcpp::PF_R
;
4053 // Add an Output_section to a PT_LOAD Output_segment.
4056 Output_segment::add_output_section_to_load(Layout
* layout
,
4058 elfcpp::Elf_Word seg_flags
)
4060 gold_assert(this->type() == elfcpp::PT_LOAD
);
4061 gold_assert((os
->flags() & elfcpp::SHF_ALLOC
) != 0);
4062 gold_assert(!this->is_max_align_known_
);
4063 gold_assert(os
->is_large_data_section() == this->is_large_data_segment());
4065 this->update_flags_for_output_section(seg_flags
);
4067 // We don't want to change the ordering if we have a linker script
4068 // with a SECTIONS clause.
4069 Output_section_order order
= os
->order();
4070 if (layout
->script_options()->saw_sections_clause())
4071 order
= static_cast<Output_section_order
>(0);
4073 gold_assert(order
!= ORDER_INVALID
);
4075 this->output_lists_
[order
].push_back(os
);
4078 // Add an Output_section to a non-PT_LOAD Output_segment.
4081 Output_segment::add_output_section_to_nonload(Output_section
* os
,
4082 elfcpp::Elf_Word seg_flags
)
4084 gold_assert(this->type() != elfcpp::PT_LOAD
);
4085 gold_assert((os
->flags() & elfcpp::SHF_ALLOC
) != 0);
4086 gold_assert(!this->is_max_align_known_
);
4088 this->update_flags_for_output_section(seg_flags
);
4090 this->output_lists_
[0].push_back(os
);
4093 // Remove an Output_section from this segment. It is an error if it
4097 Output_segment::remove_output_section(Output_section
* os
)
4099 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4101 Output_data_list
* pdl
= &this->output_lists_
[i
];
4102 for (Output_data_list::iterator p
= pdl
->begin(); p
!= pdl
->end(); ++p
)
4114 // Add an Output_data (which need not be an Output_section) to the
4115 // start of a segment.
4118 Output_segment::add_initial_output_data(Output_data
* od
)
4120 gold_assert(!this->is_max_align_known_
);
4121 Output_data_list::iterator p
= this->output_lists_
[0].begin();
4122 this->output_lists_
[0].insert(p
, od
);
4125 // Return true if this segment has any sections which hold actual
4126 // data, rather than being a BSS section.
4129 Output_segment::has_any_data_sections() const
4131 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4133 const Output_data_list
* pdl
= &this->output_lists_
[i
];
4134 for (Output_data_list::const_iterator p
= pdl
->begin();
4138 if (!(*p
)->is_section())
4140 if ((*p
)->output_section()->type() != elfcpp::SHT_NOBITS
)
4147 // Return whether the first data section (not counting TLS sections)
4148 // is a relro section.
4151 Output_segment::is_first_section_relro() const
4153 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4155 if (i
== static_cast<int>(ORDER_TLS_DATA
)
4156 || i
== static_cast<int>(ORDER_TLS_BSS
))
4158 const Output_data_list
* pdl
= &this->output_lists_
[i
];
4161 Output_data
* p
= pdl
->front();
4162 return p
->is_section() && p
->output_section()->is_relro();
4168 // Return the maximum alignment of the Output_data in Output_segment.
4171 Output_segment::maximum_alignment()
4173 if (!this->is_max_align_known_
)
4175 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4177 const Output_data_list
* pdl
= &this->output_lists_
[i
];
4178 uint64_t addralign
= Output_segment::maximum_alignment_list(pdl
);
4179 if (addralign
> this->max_align_
)
4180 this->max_align_
= addralign
;
4182 this->is_max_align_known_
= true;
4185 return this->max_align_
;
4188 // Return the maximum alignment of a list of Output_data.
4191 Output_segment::maximum_alignment_list(const Output_data_list
* pdl
)
4194 for (Output_data_list::const_iterator p
= pdl
->begin();
4198 uint64_t addralign
= (*p
)->addralign();
4199 if (addralign
> ret
)
4205 // Return whether this segment has any dynamic relocs.
4208 Output_segment::has_dynamic_reloc() const
4210 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4211 if (this->has_dynamic_reloc_list(&this->output_lists_
[i
]))
4216 // Return whether this Output_data_list has any dynamic relocs.
4219 Output_segment::has_dynamic_reloc_list(const Output_data_list
* pdl
) const
4221 for (Output_data_list::const_iterator p
= pdl
->begin();
4224 if ((*p
)->has_dynamic_reloc())
4229 // Set the section addresses for an Output_segment. If RESET is true,
4230 // reset the addresses first. ADDR is the address and *POFF is the
4231 // file offset. Set the section indexes starting with *PSHNDX.
4232 // INCREASE_RELRO is the size of the portion of the first non-relro
4233 // section that should be included in the PT_GNU_RELRO segment.
4234 // If this segment has relro sections, and has been aligned for
4235 // that purpose, set *HAS_RELRO to TRUE. Return the address of
4236 // the immediately following segment. Update *HAS_RELRO, *POFF,
4240 Output_segment::set_section_addresses(Layout
* layout
, bool reset
,
4242 unsigned int* increase_relro
,
4245 unsigned int* pshndx
)
4247 gold_assert(this->type_
== elfcpp::PT_LOAD
);
4249 uint64_t last_relro_pad
= 0;
4250 off_t orig_off
= *poff
;
4252 bool in_tls
= false;
4254 // If we have relro sections, we need to pad forward now so that the
4255 // relro sections plus INCREASE_RELRO end on an abi page boundary.
4256 if (parameters
->options().relro()
4257 && this->is_first_section_relro()
4258 && (!this->are_addresses_set_
|| reset
))
4260 uint64_t relro_size
= 0;
4262 uint64_t max_align
= 0;
4263 for (int i
= 0; i
<= static_cast<int>(ORDER_RELRO_LAST
); ++i
)
4265 Output_data_list
* pdl
= &this->output_lists_
[i
];
4266 Output_data_list::iterator p
;
4267 for (p
= pdl
->begin(); p
!= pdl
->end(); ++p
)
4269 if (!(*p
)->is_section())
4271 uint64_t align
= (*p
)->addralign();
4272 if (align
> max_align
)
4274 if ((*p
)->is_section_flag_set(elfcpp::SHF_TLS
))
4278 // Align the first non-TLS section to the alignment
4279 // of the TLS segment.
4283 relro_size
= align_address(relro_size
, align
);
4284 // Ignore the size of the .tbss section.
4285 if ((*p
)->is_section_flag_set(elfcpp::SHF_TLS
)
4286 && (*p
)->is_section_type(elfcpp::SHT_NOBITS
))
4288 if ((*p
)->is_address_valid())
4289 relro_size
+= (*p
)->data_size();
4292 // FIXME: This could be faster.
4293 (*p
)->set_address_and_file_offset(addr
+ relro_size
,
4295 relro_size
+= (*p
)->data_size();
4296 (*p
)->reset_address_and_file_offset();
4299 if (p
!= pdl
->end())
4302 relro_size
+= *increase_relro
;
4303 // Pad the total relro size to a multiple of the maximum
4304 // section alignment seen.
4305 uint64_t aligned_size
= align_address(relro_size
, max_align
);
4306 // Note the amount of padding added after the last relro section.
4307 last_relro_pad
= aligned_size
- relro_size
;
4310 uint64_t page_align
= parameters
->target().abi_pagesize();
4312 // Align to offset N such that (N + RELRO_SIZE) % PAGE_ALIGN == 0.
4313 uint64_t desired_align
= page_align
- (aligned_size
% page_align
);
4314 if (desired_align
< *poff
% page_align
)
4315 *poff
+= page_align
- *poff
% page_align
;
4316 *poff
+= desired_align
- *poff
% page_align
;
4317 addr
+= *poff
- orig_off
;
4321 if (!reset
&& this->are_addresses_set_
)
4323 gold_assert(this->paddr_
== addr
);
4324 addr
= this->vaddr_
;
4328 this->vaddr_
= addr
;
4329 this->paddr_
= addr
;
4330 this->are_addresses_set_
= true;
4335 this->offset_
= orig_off
;
4339 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4341 if (i
== static_cast<int>(ORDER_RELRO_LAST
))
4343 *poff
+= last_relro_pad
;
4344 addr
+= last_relro_pad
;
4345 if (this->output_lists_
[i
].empty())
4347 // If there is nothing in the ORDER_RELRO_LAST list,
4348 // the padding will occur at the end of the relro
4349 // segment, and we need to add it to *INCREASE_RELRO.
4350 *increase_relro
+= last_relro_pad
;
4353 addr
= this->set_section_list_addresses(layout
, reset
,
4354 &this->output_lists_
[i
],
4355 addr
, poff
, pshndx
, &in_tls
);
4356 if (i
< static_cast<int>(ORDER_SMALL_BSS
))
4358 this->filesz_
= *poff
- orig_off
;
4365 // If the last section was a TLS section, align upward to the
4366 // alignment of the TLS segment, so that the overall size of the TLS
4367 // segment is aligned.
4370 uint64_t segment_align
= layout
->tls_segment()->maximum_alignment();
4371 *poff
= align_address(*poff
, segment_align
);
4374 this->memsz_
= *poff
- orig_off
;
4376 // Ignore the file offset adjustments made by the BSS Output_data
4383 // Set the addresses and file offsets in a list of Output_data
4387 Output_segment::set_section_list_addresses(Layout
* layout
, bool reset
,
4388 Output_data_list
* pdl
,
4389 uint64_t addr
, off_t
* poff
,
4390 unsigned int* pshndx
,
4393 off_t startoff
= *poff
;
4394 // For incremental updates, we may allocate non-fixed sections from
4395 // free space in the file. This keeps track of the high-water mark.
4396 off_t maxoff
= startoff
;
4398 off_t off
= startoff
;
4399 for (Output_data_list::iterator p
= pdl
->begin();
4404 (*p
)->reset_address_and_file_offset();
4406 // When doing an incremental update or when using a linker script,
4407 // the section will most likely already have an address.
4408 if (!(*p
)->is_address_valid())
4410 uint64_t align
= (*p
)->addralign();
4412 if ((*p
)->is_section_flag_set(elfcpp::SHF_TLS
))
4414 // Give the first TLS section the alignment of the
4415 // entire TLS segment. Otherwise the TLS segment as a
4416 // whole may be misaligned.
4419 Output_segment
* tls_segment
= layout
->tls_segment();
4420 gold_assert(tls_segment
!= NULL
);
4421 uint64_t segment_align
= tls_segment
->maximum_alignment();
4422 gold_assert(segment_align
>= align
);
4423 align
= segment_align
;
4430 // If this is the first section after the TLS segment,
4431 // align it to at least the alignment of the TLS
4432 // segment, so that the size of the overall TLS segment
4436 uint64_t segment_align
=
4437 layout
->tls_segment()->maximum_alignment();
4438 if (segment_align
> align
)
4439 align
= segment_align
;
4445 if (!parameters
->incremental_update())
4447 off
= align_address(off
, align
);
4448 (*p
)->set_address_and_file_offset(addr
+ (off
- startoff
), off
);
4452 // Incremental update: allocate file space from free list.
4453 (*p
)->pre_finalize_data_size();
4454 off_t current_size
= (*p
)->current_data_size();
4455 off
= layout
->allocate(current_size
, align
, startoff
);
4458 gold_assert((*p
)->output_section() != NULL
);
4459 gold_fallback(_("out of patch space for section %s; "
4460 "relink with --incremental-full"),
4461 (*p
)->output_section()->name());
4463 (*p
)->set_address_and_file_offset(addr
+ (off
- startoff
), off
);
4464 if ((*p
)->data_size() > current_size
)
4466 gold_assert((*p
)->output_section() != NULL
);
4467 gold_fallback(_("%s: section changed size; "
4468 "relink with --incremental-full"),
4469 (*p
)->output_section()->name());
4473 else if (parameters
->incremental_update())
4475 // For incremental updates, use the fixed offset for the
4476 // high-water mark computation.
4477 off
= (*p
)->offset();
4481 // The script may have inserted a skip forward, but it
4482 // better not have moved backward.
4483 if ((*p
)->address() >= addr
+ (off
- startoff
))
4484 off
+= (*p
)->address() - (addr
+ (off
- startoff
));
4487 if (!layout
->script_options()->saw_sections_clause())
4491 Output_section
* os
= (*p
)->output_section();
4493 // Cast to unsigned long long to avoid format warnings.
4494 unsigned long long previous_dot
=
4495 static_cast<unsigned long long>(addr
+ (off
- startoff
));
4496 unsigned long long dot
=
4497 static_cast<unsigned long long>((*p
)->address());
4500 gold_error(_("dot moves backward in linker script "
4501 "from 0x%llx to 0x%llx"), previous_dot
, dot
);
4503 gold_error(_("address of section '%s' moves backward "
4504 "from 0x%llx to 0x%llx"),
4505 os
->name(), previous_dot
, dot
);
4508 (*p
)->set_file_offset(off
);
4509 (*p
)->finalize_data_size();
4512 if (parameters
->incremental_update())
4513 gold_debug(DEBUG_INCREMENTAL
,
4514 "set_section_list_addresses: %08lx %08lx %s",
4515 static_cast<long>(off
),
4516 static_cast<long>((*p
)->data_size()),
4517 ((*p
)->output_section() != NULL
4518 ? (*p
)->output_section()->name() : "(special)"));
4520 // We want to ignore the size of a SHF_TLS SHT_NOBITS
4521 // section. Such a section does not affect the size of a
4523 if (!(*p
)->is_section_flag_set(elfcpp::SHF_TLS
)
4524 || !(*p
)->is_section_type(elfcpp::SHT_NOBITS
))
4525 off
+= (*p
)->data_size();
4530 if ((*p
)->is_section())
4532 (*p
)->set_out_shndx(*pshndx
);
4538 return addr
+ (maxoff
- startoff
);
4541 // For a non-PT_LOAD segment, set the offset from the sections, if
4542 // any. Add INCREASE to the file size and the memory size.
4545 Output_segment::set_offset(unsigned int increase
)
4547 gold_assert(this->type_
!= elfcpp::PT_LOAD
);
4549 gold_assert(!this->are_addresses_set_
);
4551 // A non-load section only uses output_lists_[0].
4553 Output_data_list
* pdl
= &this->output_lists_
[0];
4557 gold_assert(increase
== 0);
4560 this->are_addresses_set_
= true;
4562 this->min_p_align_
= 0;
4568 // Find the first and last section by address.
4569 const Output_data
* first
= NULL
;
4570 const Output_data
* last_data
= NULL
;
4571 const Output_data
* last_bss
= NULL
;
4572 for (Output_data_list::const_iterator p
= pdl
->begin();
4577 || (*p
)->address() < first
->address()
4578 || ((*p
)->address() == first
->address()
4579 && (*p
)->data_size() < first
->data_size()))
4581 const Output_data
** plast
;
4582 if ((*p
)->is_section()
4583 && (*p
)->output_section()->type() == elfcpp::SHT_NOBITS
)
4588 || (*p
)->address() > (*plast
)->address()
4589 || ((*p
)->address() == (*plast
)->address()
4590 && (*p
)->data_size() > (*plast
)->data_size()))
4594 this->vaddr_
= first
->address();
4595 this->paddr_
= (first
->has_load_address()
4596 ? first
->load_address()
4598 this->are_addresses_set_
= true;
4599 this->offset_
= first
->offset();
4601 if (last_data
== NULL
)
4604 this->filesz_
= (last_data
->address()
4605 + last_data
->data_size()
4608 const Output_data
* last
= last_bss
!= NULL
? last_bss
: last_data
;
4609 this->memsz_
= (last
->address()
4613 this->filesz_
+= increase
;
4614 this->memsz_
+= increase
;
4616 // If this is a RELRO segment, verify that the segment ends at a
4618 if (this->type_
== elfcpp::PT_GNU_RELRO
)
4620 uint64_t page_align
= parameters
->target().abi_pagesize();
4621 uint64_t segment_end
= this->vaddr_
+ this->memsz_
;
4622 if (parameters
->incremental_update())
4624 // The INCREASE_RELRO calculation is bypassed for an incremental
4625 // update, so we need to adjust the segment size manually here.
4626 segment_end
= align_address(segment_end
, page_align
);
4627 this->memsz_
= segment_end
- this->vaddr_
;
4630 gold_assert(segment_end
== align_address(segment_end
, page_align
));
4633 // If this is a TLS segment, align the memory size. The code in
4634 // set_section_list ensures that the section after the TLS segment
4635 // is aligned to give us room.
4636 if (this->type_
== elfcpp::PT_TLS
)
4638 uint64_t segment_align
= this->maximum_alignment();
4639 gold_assert(this->vaddr_
== align_address(this->vaddr_
, segment_align
));
4640 this->memsz_
= align_address(this->memsz_
, segment_align
);
4644 // Set the TLS offsets of the sections in the PT_TLS segment.
4647 Output_segment::set_tls_offsets()
4649 gold_assert(this->type_
== elfcpp::PT_TLS
);
4651 for (Output_data_list::iterator p
= this->output_lists_
[0].begin();
4652 p
!= this->output_lists_
[0].end();
4654 (*p
)->set_tls_offset(this->vaddr_
);
4657 // Return the first section.
4660 Output_segment::first_section() const
4662 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4664 const Output_data_list
* pdl
= &this->output_lists_
[i
];
4665 for (Output_data_list::const_iterator p
= pdl
->begin();
4669 if ((*p
)->is_section())
4670 return (*p
)->output_section();
4676 // Return the number of Output_sections in an Output_segment.
4679 Output_segment::output_section_count() const
4681 unsigned int ret
= 0;
4682 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4683 ret
+= this->output_section_count_list(&this->output_lists_
[i
]);
4687 // Return the number of Output_sections in an Output_data_list.
4690 Output_segment::output_section_count_list(const Output_data_list
* pdl
) const
4692 unsigned int count
= 0;
4693 for (Output_data_list::const_iterator p
= pdl
->begin();
4697 if ((*p
)->is_section())
4703 // Return the section attached to the list segment with the lowest
4704 // load address. This is used when handling a PHDRS clause in a
4708 Output_segment::section_with_lowest_load_address() const
4710 Output_section
* found
= NULL
;
4711 uint64_t found_lma
= 0;
4712 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4713 this->lowest_load_address_in_list(&this->output_lists_
[i
], &found
,
4718 // Look through a list for a section with a lower load address.
4721 Output_segment::lowest_load_address_in_list(const Output_data_list
* pdl
,
4722 Output_section
** found
,
4723 uint64_t* found_lma
) const
4725 for (Output_data_list::const_iterator p
= pdl
->begin();
4729 if (!(*p
)->is_section())
4731 Output_section
* os
= static_cast<Output_section
*>(*p
);
4732 uint64_t lma
= (os
->has_load_address()
4733 ? os
->load_address()
4735 if (*found
== NULL
|| lma
< *found_lma
)
4743 // Write the segment data into *OPHDR.
4745 template<int size
, bool big_endian
>
4747 Output_segment::write_header(elfcpp::Phdr_write
<size
, big_endian
>* ophdr
)
4749 ophdr
->put_p_type(this->type_
);
4750 ophdr
->put_p_offset(this->offset_
);
4751 ophdr
->put_p_vaddr(this->vaddr_
);
4752 ophdr
->put_p_paddr(this->paddr_
);
4753 ophdr
->put_p_filesz(this->filesz_
);
4754 ophdr
->put_p_memsz(this->memsz_
);
4755 ophdr
->put_p_flags(this->flags_
);
4756 ophdr
->put_p_align(std::max(this->min_p_align_
, this->maximum_alignment()));
4759 // Write the section headers into V.
4761 template<int size
, bool big_endian
>
4763 Output_segment::write_section_headers(const Layout
* layout
,
4764 const Stringpool
* secnamepool
,
4766 unsigned int* pshndx
) const
4768 // Every section that is attached to a segment must be attached to a
4769 // PT_LOAD segment, so we only write out section headers for PT_LOAD
4771 if (this->type_
!= elfcpp::PT_LOAD
)
4774 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4776 const Output_data_list
* pdl
= &this->output_lists_
[i
];
4777 v
= this->write_section_headers_list
<size
, big_endian
>(layout
,
4786 template<int size
, bool big_endian
>
4788 Output_segment::write_section_headers_list(const Layout
* layout
,
4789 const Stringpool
* secnamepool
,
4790 const Output_data_list
* pdl
,
4792 unsigned int* pshndx
) const
4794 const int shdr_size
= elfcpp::Elf_sizes
<size
>::shdr_size
;
4795 for (Output_data_list::const_iterator p
= pdl
->begin();
4799 if ((*p
)->is_section())
4801 const Output_section
* ps
= static_cast<const Output_section
*>(*p
);
4802 gold_assert(*pshndx
== ps
->out_shndx());
4803 elfcpp::Shdr_write
<size
, big_endian
> oshdr(v
);
4804 ps
->write_header(layout
, secnamepool
, &oshdr
);
4812 // Print the output sections to the map file.
4815 Output_segment::print_sections_to_mapfile(Mapfile
* mapfile
) const
4817 if (this->type() != elfcpp::PT_LOAD
)
4819 for (int i
= 0; i
< static_cast<int>(ORDER_MAX
); ++i
)
4820 this->print_section_list_to_mapfile(mapfile
, &this->output_lists_
[i
]);
4823 // Print an output section list to the map file.
4826 Output_segment::print_section_list_to_mapfile(Mapfile
* mapfile
,
4827 const Output_data_list
* pdl
) const
4829 for (Output_data_list::const_iterator p
= pdl
->begin();
4832 (*p
)->print_to_mapfile(mapfile
);
4835 // Output_file methods.
4837 Output_file::Output_file(const char* name
)
4842 map_is_anonymous_(false),
4843 map_is_allocated_(false),
4844 is_temporary_(false)
4848 // Try to open an existing file. Returns false if the file doesn't
4849 // exist, has a size of 0 or can't be mmapped. If BASE_NAME is not
4850 // NULL, open that file as the base for incremental linking, and
4851 // copy its contents to the new output file. This routine can
4852 // be called for incremental updates, in which case WRITABLE should
4853 // be true, or by the incremental-dump utility, in which case
4854 // WRITABLE should be false.
4857 Output_file::open_base_file(const char* base_name
, bool writable
)
4859 // The name "-" means "stdout".
4860 if (strcmp(this->name_
, "-") == 0)
4863 bool use_base_file
= base_name
!= NULL
;
4865 base_name
= this->name_
;
4866 else if (strcmp(base_name
, this->name_
) == 0)
4867 gold_fatal(_("%s: incremental base and output file name are the same"),
4870 // Don't bother opening files with a size of zero.
4872 if (::stat(base_name
, &s
) != 0)
4874 gold_info(_("%s: stat: %s"), base_name
, strerror(errno
));
4879 gold_info(_("%s: incremental base file is empty"), base_name
);
4883 // If we're using a base file, we want to open it read-only.
4887 int oflags
= writable
? O_RDWR
: O_RDONLY
;
4888 int o
= open_descriptor(-1, base_name
, oflags
, 0);
4891 gold_info(_("%s: open: %s"), base_name
, strerror(errno
));
4895 // If the base file and the output file are different, open a
4896 // new output file and read the contents from the base file into
4897 // the newly-mapped region.
4900 this->open(s
.st_size
);
4901 ssize_t bytes_to_read
= s
.st_size
;
4902 unsigned char* p
= this->base_
;
4903 while (bytes_to_read
> 0)
4905 ssize_t len
= ::read(o
, p
, bytes_to_read
);
4908 gold_info(_("%s: read failed: %s"), base_name
, strerror(errno
));
4913 gold_info(_("%s: file too short: read only %lld of %lld bytes"),
4915 static_cast<long long>(s
.st_size
- bytes_to_read
),
4916 static_cast<long long>(s
.st_size
));
4920 bytes_to_read
-= len
;
4927 this->file_size_
= s
.st_size
;
4929 if (!this->map_no_anonymous(writable
))
4931 release_descriptor(o
, true);
4933 this->file_size_
= 0;
4940 // Open the output file.
4943 Output_file::open(off_t file_size
)
4945 this->file_size_
= file_size
;
4947 // Unlink the file first; otherwise the open() may fail if the file
4948 // is busy (e.g. it's an executable that's currently being executed).
4950 // However, the linker may be part of a system where a zero-length
4951 // file is created for it to write to, with tight permissions (gcc
4952 // 2.95 did something like this). Unlinking the file would work
4953 // around those permission controls, so we only unlink if the file
4954 // has a non-zero size. We also unlink only regular files to avoid
4955 // trouble with directories/etc.
4957 // If we fail, continue; this command is merely a best-effort attempt
4958 // to improve the odds for open().
4960 // We let the name "-" mean "stdout"
4961 if (!this->is_temporary_
)
4963 if (strcmp(this->name_
, "-") == 0)
4964 this->o_
= STDOUT_FILENO
;
4968 if (::stat(this->name_
, &s
) == 0
4969 && (S_ISREG (s
.st_mode
) || S_ISLNK (s
.st_mode
)))
4972 ::unlink(this->name_
);
4973 else if (!parameters
->options().relocatable())
4975 // If we don't unlink the existing file, add execute
4976 // permission where read permissions already exist
4977 // and where the umask permits.
4978 int mask
= ::umask(0);
4980 s
.st_mode
|= (s
.st_mode
& 0444) >> 2;
4981 ::chmod(this->name_
, s
.st_mode
& ~mask
);
4985 int mode
= parameters
->options().relocatable() ? 0666 : 0777;
4986 int o
= open_descriptor(-1, this->name_
, O_RDWR
| O_CREAT
| O_TRUNC
,
4989 gold_fatal(_("%s: open: %s"), this->name_
, strerror(errno
));
4997 // Resize the output file.
5000 Output_file::resize(off_t file_size
)
5002 // If the mmap is mapping an anonymous memory buffer, this is easy:
5003 // just mremap to the new size. If it's mapping to a file, we want
5004 // to unmap to flush to the file, then remap after growing the file.
5005 if (this->map_is_anonymous_
)
5008 if (!this->map_is_allocated_
)
5010 base
= ::mremap(this->base_
, this->file_size_
, file_size
,
5012 if (base
== MAP_FAILED
)
5013 gold_fatal(_("%s: mremap: %s"), this->name_
, strerror(errno
));
5017 base
= realloc(this->base_
, file_size
);
5020 if (file_size
> this->file_size_
)
5021 memset(static_cast<char*>(base
) + this->file_size_
, 0,
5022 file_size
- this->file_size_
);
5024 this->base_
= static_cast<unsigned char*>(base
);
5025 this->file_size_
= file_size
;
5030 this->file_size_
= file_size
;
5031 if (!this->map_no_anonymous(true))
5032 gold_fatal(_("%s: mmap: %s"), this->name_
, strerror(errno
));
5036 // Map an anonymous block of memory which will later be written to the
5037 // file. Return whether the map succeeded.
5040 Output_file::map_anonymous()
5042 void* base
= ::mmap(NULL
, this->file_size_
, PROT_READ
| PROT_WRITE
,
5043 MAP_PRIVATE
| MAP_ANONYMOUS
, -1, 0);
5044 if (base
== MAP_FAILED
)
5046 base
= malloc(this->file_size_
);
5049 memset(base
, 0, this->file_size_
);
5050 this->map_is_allocated_
= true;
5052 this->base_
= static_cast<unsigned char*>(base
);
5053 this->map_is_anonymous_
= true;
5057 // Map the file into memory. Return whether the mapping succeeded.
5058 // If WRITABLE is true, map with write access.
5061 Output_file::map_no_anonymous(bool writable
)
5063 const int o
= this->o_
;
5065 // If the output file is not a regular file, don't try to mmap it;
5066 // instead, we'll mmap a block of memory (an anonymous buffer), and
5067 // then later write the buffer to the file.
5069 struct stat statbuf
;
5070 if (o
== STDOUT_FILENO
|| o
== STDERR_FILENO
5071 || ::fstat(o
, &statbuf
) != 0
5072 || !S_ISREG(statbuf
.st_mode
)
5073 || this->is_temporary_
)
5076 // Ensure that we have disk space available for the file. If we
5077 // don't do this, it is possible that we will call munmap, close,
5078 // and exit with dirty buffers still in the cache with no assigned
5079 // disk blocks. If the disk is out of space at that point, the
5080 // output file will wind up incomplete, but we will have already
5081 // exited. The alternative to fallocate would be to use fdatasync,
5082 // but that would be a more significant performance hit.
5085 int err
= gold_fallocate(o
, 0, this->file_size_
);
5087 gold_fatal(_("%s: %s"), this->name_
, strerror(err
));
5090 // Map the file into memory.
5091 int prot
= PROT_READ
;
5094 base
= ::mmap(NULL
, this->file_size_
, prot
, MAP_SHARED
, o
, 0);
5096 // The mmap call might fail because of file system issues: the file
5097 // system might not support mmap at all, or it might not support
5098 // mmap with PROT_WRITE.
5099 if (base
== MAP_FAILED
)
5102 this->map_is_anonymous_
= false;
5103 this->base_
= static_cast<unsigned char*>(base
);
5107 // Map the file into memory.
5112 if (parameters
->options().mmap_output_file()
5113 && this->map_no_anonymous(true))
5116 // The mmap call might fail because of file system issues: the file
5117 // system might not support mmap at all, or it might not support
5118 // mmap with PROT_WRITE. I'm not sure which errno values we will
5119 // see in all cases, so if the mmap fails for any reason and we
5120 // don't care about file contents, try for an anonymous map.
5121 if (this->map_anonymous())
5124 gold_fatal(_("%s: mmap: failed to allocate %lu bytes for output file: %s"),
5125 this->name_
, static_cast<unsigned long>(this->file_size_
),
5129 // Unmap the file from memory.
5132 Output_file::unmap()
5134 if (this->map_is_anonymous_
)
5136 // We've already written out the data, so there is no reason to
5137 // waste time unmapping or freeing the memory.
5141 if (::munmap(this->base_
, this->file_size_
) < 0)
5142 gold_error(_("%s: munmap: %s"), this->name_
, strerror(errno
));
5147 // Close the output file.
5150 Output_file::close()
5152 // If the map isn't file-backed, we need to write it now.
5153 if (this->map_is_anonymous_
&& !this->is_temporary_
)
5155 size_t bytes_to_write
= this->file_size_
;
5157 while (bytes_to_write
> 0)
5159 ssize_t bytes_written
= ::write(this->o_
, this->base_
+ offset
,
5161 if (bytes_written
== 0)
5162 gold_error(_("%s: write: unexpected 0 return-value"), this->name_
);
5163 else if (bytes_written
< 0)
5164 gold_error(_("%s: write: %s"), this->name_
, strerror(errno
));
5167 bytes_to_write
-= bytes_written
;
5168 offset
+= bytes_written
;
5174 // We don't close stdout or stderr
5175 if (this->o_
!= STDOUT_FILENO
5176 && this->o_
!= STDERR_FILENO
5177 && !this->is_temporary_
)
5178 if (::close(this->o_
) < 0)
5179 gold_error(_("%s: close: %s"), this->name_
, strerror(errno
));
5183 // Instantiate the templates we need. We could use the configure
5184 // script to restrict this to only the ones for implemented targets.
5186 #ifdef HAVE_TARGET_32_LITTLE
5189 Output_section::add_input_section
<32, false>(
5191 Sized_relobj_file
<32, false>* object
,
5193 const char* secname
,
5194 const elfcpp::Shdr
<32, false>& shdr
,
5195 unsigned int reloc_shndx
,
5196 bool have_sections_script
);
5199 #ifdef HAVE_TARGET_32_BIG
5202 Output_section::add_input_section
<32, true>(
5204 Sized_relobj_file
<32, true>* object
,
5206 const char* secname
,
5207 const elfcpp::Shdr
<32, true>& shdr
,
5208 unsigned int reloc_shndx
,
5209 bool have_sections_script
);
5212 #ifdef HAVE_TARGET_64_LITTLE
5215 Output_section::add_input_section
<64, false>(
5217 Sized_relobj_file
<64, false>* object
,
5219 const char* secname
,
5220 const elfcpp::Shdr
<64, false>& shdr
,
5221 unsigned int reloc_shndx
,
5222 bool have_sections_script
);
5225 #ifdef HAVE_TARGET_64_BIG
5228 Output_section::add_input_section
<64, true>(
5230 Sized_relobj_file
<64, true>* object
,
5232 const char* secname
,
5233 const elfcpp::Shdr
<64, true>& shdr
,
5234 unsigned int reloc_shndx
,
5235 bool have_sections_script
);
5238 #ifdef HAVE_TARGET_32_LITTLE
5240 class Output_reloc
<elfcpp::SHT_REL
, false, 32, false>;
5243 #ifdef HAVE_TARGET_32_BIG
5245 class Output_reloc
<elfcpp::SHT_REL
, false, 32, true>;
5248 #ifdef HAVE_TARGET_64_LITTLE
5250 class Output_reloc
<elfcpp::SHT_REL
, false, 64, false>;
5253 #ifdef HAVE_TARGET_64_BIG
5255 class Output_reloc
<elfcpp::SHT_REL
, false, 64, true>;
5258 #ifdef HAVE_TARGET_32_LITTLE
5260 class Output_reloc
<elfcpp::SHT_REL
, true, 32, false>;
5263 #ifdef HAVE_TARGET_32_BIG
5265 class Output_reloc
<elfcpp::SHT_REL
, true, 32, true>;
5268 #ifdef HAVE_TARGET_64_LITTLE
5270 class Output_reloc
<elfcpp::SHT_REL
, true, 64, false>;
5273 #ifdef HAVE_TARGET_64_BIG
5275 class Output_reloc
<elfcpp::SHT_REL
, true, 64, true>;
5278 #ifdef HAVE_TARGET_32_LITTLE
5280 class Output_reloc
<elfcpp::SHT_RELA
, false, 32, false>;
5283 #ifdef HAVE_TARGET_32_BIG
5285 class Output_reloc
<elfcpp::SHT_RELA
, false, 32, true>;
5288 #ifdef HAVE_TARGET_64_LITTLE
5290 class Output_reloc
<elfcpp::SHT_RELA
, false, 64, false>;
5293 #ifdef HAVE_TARGET_64_BIG
5295 class Output_reloc
<elfcpp::SHT_RELA
, false, 64, true>;
5298 #ifdef HAVE_TARGET_32_LITTLE
5300 class Output_reloc
<elfcpp::SHT_RELA
, true, 32, false>;
5303 #ifdef HAVE_TARGET_32_BIG
5305 class Output_reloc
<elfcpp::SHT_RELA
, true, 32, true>;
5308 #ifdef HAVE_TARGET_64_LITTLE
5310 class Output_reloc
<elfcpp::SHT_RELA
, true, 64, false>;
5313 #ifdef HAVE_TARGET_64_BIG
5315 class Output_reloc
<elfcpp::SHT_RELA
, true, 64, true>;
5318 #ifdef HAVE_TARGET_32_LITTLE
5320 class Output_data_reloc
<elfcpp::SHT_REL
, false, 32, false>;
5323 #ifdef HAVE_TARGET_32_BIG
5325 class Output_data_reloc
<elfcpp::SHT_REL
, false, 32, true>;
5328 #ifdef HAVE_TARGET_64_LITTLE
5330 class Output_data_reloc
<elfcpp::SHT_REL
, false, 64, false>;
5333 #ifdef HAVE_TARGET_64_BIG
5335 class Output_data_reloc
<elfcpp::SHT_REL
, false, 64, true>;
5338 #ifdef HAVE_TARGET_32_LITTLE
5340 class Output_data_reloc
<elfcpp::SHT_REL
, true, 32, false>;
5343 #ifdef HAVE_TARGET_32_BIG
5345 class Output_data_reloc
<elfcpp::SHT_REL
, true, 32, true>;
5348 #ifdef HAVE_TARGET_64_LITTLE
5350 class Output_data_reloc
<elfcpp::SHT_REL
, true, 64, false>;
5353 #ifdef HAVE_TARGET_64_BIG
5355 class Output_data_reloc
<elfcpp::SHT_REL
, true, 64, true>;
5358 #ifdef HAVE_TARGET_32_LITTLE
5360 class Output_data_reloc
<elfcpp::SHT_RELA
, false, 32, false>;
5363 #ifdef HAVE_TARGET_32_BIG
5365 class Output_data_reloc
<elfcpp::SHT_RELA
, false, 32, true>;
5368 #ifdef HAVE_TARGET_64_LITTLE
5370 class Output_data_reloc
<elfcpp::SHT_RELA
, false, 64, false>;
5373 #ifdef HAVE_TARGET_64_BIG
5375 class Output_data_reloc
<elfcpp::SHT_RELA
, false, 64, true>;
5378 #ifdef HAVE_TARGET_32_LITTLE
5380 class Output_data_reloc
<elfcpp::SHT_RELA
, true, 32, false>;
5383 #ifdef HAVE_TARGET_32_BIG
5385 class Output_data_reloc
<elfcpp::SHT_RELA
, true, 32, true>;
5388 #ifdef HAVE_TARGET_64_LITTLE
5390 class Output_data_reloc
<elfcpp::SHT_RELA
, true, 64, false>;
5393 #ifdef HAVE_TARGET_64_BIG
5395 class Output_data_reloc
<elfcpp::SHT_RELA
, true, 64, true>;
5398 #ifdef HAVE_TARGET_32_LITTLE
5400 class Output_relocatable_relocs
<elfcpp::SHT_REL
, 32, false>;
5403 #ifdef HAVE_TARGET_32_BIG
5405 class Output_relocatable_relocs
<elfcpp::SHT_REL
, 32, true>;
5408 #ifdef HAVE_TARGET_64_LITTLE
5410 class Output_relocatable_relocs
<elfcpp::SHT_REL
, 64, false>;
5413 #ifdef HAVE_TARGET_64_BIG
5415 class Output_relocatable_relocs
<elfcpp::SHT_REL
, 64, true>;
5418 #ifdef HAVE_TARGET_32_LITTLE
5420 class Output_relocatable_relocs
<elfcpp::SHT_RELA
, 32, false>;
5423 #ifdef HAVE_TARGET_32_BIG
5425 class Output_relocatable_relocs
<elfcpp::SHT_RELA
, 32, true>;
5428 #ifdef HAVE_TARGET_64_LITTLE
5430 class Output_relocatable_relocs
<elfcpp::SHT_RELA
, 64, false>;
5433 #ifdef HAVE_TARGET_64_BIG
5435 class Output_relocatable_relocs
<elfcpp::SHT_RELA
, 64, true>;
5438 #ifdef HAVE_TARGET_32_LITTLE
5440 class Output_data_group
<32, false>;
5443 #ifdef HAVE_TARGET_32_BIG
5445 class Output_data_group
<32, true>;
5448 #ifdef HAVE_TARGET_64_LITTLE
5450 class Output_data_group
<64, false>;
5453 #ifdef HAVE_TARGET_64_BIG
5455 class Output_data_group
<64, true>;
5459 class Output_data_got
<32, false>;
5462 class Output_data_got
<32, true>;
5465 class Output_data_got
<64, false>;
5468 class Output_data_got
<64, true>;
5470 } // End namespace gold.