blob: 0a9e58f71d2d3268b207c6634eb0fa397c5a3dcc [file] [log] [blame]
// output.cc -- manage the output file for gold
// Copyright (C) 2006-2016 Free Software Foundation, Inc.
// Written by Ian Lance Taylor <iant@google.com>.
// This file is part of gold.
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
// MA 02110-1301, USA.
#include "gold.h"
#include <cstdlib>
#include <cstring>
#include <cerrno>
#include <fcntl.h>
#include <unistd.h>
#include <sys/stat.h>
#include <algorithm>
#ifdef HAVE_SYS_MMAN_H
#include <sys/mman.h>
#endif
#include "libiberty.h"
#include "dwarf.h"
#include "parameters.h"
#include "object.h"
#include "symtab.h"
#include "reloc.h"
#include "merge.h"
#include "descriptors.h"
#include "layout.h"
#include "output.h"
// For systems without mmap support.
#ifndef HAVE_MMAP
# define mmap gold_mmap
# define munmap gold_munmap
# define mremap gold_mremap
# ifndef MAP_FAILED
# define MAP_FAILED (reinterpret_cast<void*>(-1))
# endif
# ifndef PROT_READ
# define PROT_READ 0
# endif
# ifndef PROT_WRITE
# define PROT_WRITE 0
# endif
# ifndef MAP_PRIVATE
# define MAP_PRIVATE 0
# endif
# ifndef MAP_ANONYMOUS
# define MAP_ANONYMOUS 0
# endif
# ifndef MAP_SHARED
# define MAP_SHARED 0
# endif
# ifndef ENOSYS
# define ENOSYS EINVAL
# endif
static void *
gold_mmap(void *, size_t, int, int, int, off_t)
{
errno = ENOSYS;
return MAP_FAILED;
}
static int
gold_munmap(void *, size_t)
{
errno = ENOSYS;
return -1;
}
static void *
gold_mremap(void *, size_t, size_t, int)
{
errno = ENOSYS;
return MAP_FAILED;
}
#endif
#if defined(HAVE_MMAP) && !defined(HAVE_MREMAP)
# define mremap gold_mremap
extern "C" void *gold_mremap(void *, size_t, size_t, int);
#endif
// Some BSD systems still use MAP_ANON instead of MAP_ANONYMOUS
#ifndef MAP_ANONYMOUS
# define MAP_ANONYMOUS MAP_ANON
#endif
#ifndef MREMAP_MAYMOVE
# define MREMAP_MAYMOVE 1
#endif
// Mingw does not have S_ISLNK.
#ifndef S_ISLNK
# define S_ISLNK(mode) 0
#endif
namespace gold
{
// A wrapper around posix_fallocate. If we don't have posix_fallocate,
// or the --no-posix-fallocate option is set, we try the fallocate
// system call directly. If that fails, we use ftruncate to set
// the file size and hope that there is enough disk space.
static int
gold_fallocate(int o, off_t offset, off_t len)
{
#ifdef HAVE_POSIX_FALLOCATE
if (parameters->options().posix_fallocate())
return ::posix_fallocate(o, offset, len);
#endif // defined(HAVE_POSIX_FALLOCATE)
#ifdef HAVE_FALLOCATE
if (::fallocate(o, 0, offset, len) == 0)
return 0;
#endif // defined(HAVE_FALLOCATE)
if (::ftruncate(o, offset + len) < 0)
return errno;
return 0;
}
// Output_data variables.
bool Output_data::allocated_sizes_are_fixed;
// Output_data methods.
Output_data::~Output_data()
{
}
// Return the default alignment for the target size.
uint64_t
Output_data::default_alignment()
{
return Output_data::default_alignment_for_size(
parameters->target().get_size());
}
// Return the default alignment for a size--32 or 64.
uint64_t
Output_data::default_alignment_for_size(int size)
{
if (size == 32)
return 4;
else if (size == 64)
return 8;
else
gold_unreachable();
}
// Output_section_header methods. This currently assumes that the
// segment and section lists are complete at construction time.
Output_section_headers::Output_section_headers(
const Layout* layout,
const Layout::Segment_list* segment_list,
const Layout::Section_list* section_list,
const Layout::Section_list* unattached_section_list,
const Stringpool* secnamepool,
const Output_section* shstrtab_section)
: layout_(layout),
segment_list_(segment_list),
section_list_(section_list),
unattached_section_list_(unattached_section_list),
secnamepool_(secnamepool),
shstrtab_section_(shstrtab_section)
{
}
// Compute the current data size.
off_t
Output_section_headers::do_size() const
{
// Count all the sections. Start with 1 for the null section.
off_t count = 1;
if (!parameters->options().relocatable())
{
for (Layout::Segment_list::const_iterator p =
this->segment_list_->begin();
p != this->segment_list_->end();
++p)
if ((*p)->type() == elfcpp::PT_LOAD)
count += (*p)->output_section_count();
}
else
{
for (Layout::Section_list::const_iterator p =
this->section_list_->begin();
p != this->section_list_->end();
++p)
if (((*p)->flags() & elfcpp::SHF_ALLOC) != 0)
++count;
}
count += this->unattached_section_list_->size();
const int size = parameters->target().get_size();
int shdr_size;
if (size == 32)
shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
else if (size == 64)
shdr_size = elfcpp::Elf_sizes<64>::shdr_size;
else
gold_unreachable();
return count * shdr_size;
}
// Write out the section headers.
void
Output_section_headers::do_write(Output_file* of)
{
switch (parameters->size_and_endianness())
{
#ifdef HAVE_TARGET_32_LITTLE
case Parameters::TARGET_32_LITTLE:
this->do_sized_write<32, false>(of);
break;
#endif
#ifdef HAVE_TARGET_32_BIG
case Parameters::TARGET_32_BIG:
this->do_sized_write<32, true>(of);
break;
#endif
#ifdef HAVE_TARGET_64_LITTLE
case Parameters::TARGET_64_LITTLE:
this->do_sized_write<64, false>(of);
break;
#endif
#ifdef HAVE_TARGET_64_BIG
case Parameters::TARGET_64_BIG:
this->do_sized_write<64, true>(of);
break;
#endif
default:
gold_unreachable();
}
}
template<int size, bool big_endian>
void
Output_section_headers::do_sized_write(Output_file* of)
{
off_t all_shdrs_size = this->data_size();
unsigned char* view = of->get_output_view(this->offset(), all_shdrs_size);
const int shdr_size = elfcpp::Elf_sizes<size>::shdr_size;
unsigned char* v = view;
{
typename elfcpp::Shdr_write<size, big_endian> oshdr(v);
oshdr.put_sh_name(0);
oshdr.put_sh_type(elfcpp::SHT_NULL);
oshdr.put_sh_flags(0);
oshdr.put_sh_addr(0);
oshdr.put_sh_offset(0);
size_t section_count = (this->data_size()
/ elfcpp::Elf_sizes<size>::shdr_size);
if (section_count < elfcpp::SHN_LORESERVE)
oshdr.put_sh_size(0);
else
oshdr.put_sh_size(section_count);
unsigned int shstrndx = this->shstrtab_section_->out_shndx();
if (shstrndx < elfcpp::SHN_LORESERVE)
oshdr.put_sh_link(0);
else
oshdr.put_sh_link(shstrndx);
size_t segment_count = this->segment_list_->size();
oshdr.put_sh_info(segment_count >= elfcpp::PN_XNUM ? segment_count : 0);
oshdr.put_sh_addralign(0);
oshdr.put_sh_entsize(0);
}
v += shdr_size;
unsigned int shndx = 1;
if (!parameters->options().relocatable())
{
for (Layout::Segment_list::const_iterator p =
this->segment_list_->begin();
p != this->segment_list_->end();
++p)
v = (*p)->write_section_headers<size, big_endian>(this->layout_,
this->secnamepool_,
v,
&shndx);
}
else
{
for (Layout::Section_list::const_iterator p =
this->section_list_->begin();
p != this->section_list_->end();
++p)
{
// We do unallocated sections below, except that group
// sections have to come first.
if (((*p)->flags() & elfcpp::SHF_ALLOC) == 0
&& (*p)->type() != elfcpp::SHT_GROUP)
continue;
gold_assert(shndx == (*p)->out_shndx());
elfcpp::Shdr_write<size, big_endian> oshdr(v);
(*p)->write_header(this->layout_, this->secnamepool_, &oshdr);
v += shdr_size;
++shndx;
}
}
for (Layout::Section_list::const_iterator p =
this->unattached_section_list_->begin();
p != this->unattached_section_list_->end();
++p)
{
// For a relocatable link, we did unallocated group sections
// above, since they have to come first.
if ((*p)->type() == elfcpp::SHT_GROUP
&& parameters->options().relocatable())
continue;
gold_assert(shndx == (*p)->out_shndx());
elfcpp::Shdr_write<size, big_endian> oshdr(v);
(*p)->write_header(this->layout_, this->secnamepool_, &oshdr);
v += shdr_size;
++shndx;
}
of->write_output_view(this->offset(), all_shdrs_size, view);
}
// Output_segment_header methods.
Output_segment_headers::Output_segment_headers(
const Layout::Segment_list& segment_list)
: segment_list_(segment_list)
{
this->set_current_data_size_for_child(this->do_size());
}
void
Output_segment_headers::do_write(Output_file* of)
{
switch (parameters->size_and_endianness())
{
#ifdef HAVE_TARGET_32_LITTLE
case Parameters::TARGET_32_LITTLE:
this->do_sized_write<32, false>(of);
break;
#endif
#ifdef HAVE_TARGET_32_BIG
case Parameters::TARGET_32_BIG:
this->do_sized_write<32, true>(of);
break;
#endif
#ifdef HAVE_TARGET_64_LITTLE
case Parameters::TARGET_64_LITTLE:
this->do_sized_write<64, false>(of);
break;
#endif
#ifdef HAVE_TARGET_64_BIG
case Parameters::TARGET_64_BIG:
this->do_sized_write<64, true>(of);
break;
#endif
default:
gold_unreachable();
}
}
template<int size, bool big_endian>
void
Output_segment_headers::do_sized_write(Output_file* of)
{
const int phdr_size = elfcpp::Elf_sizes<size>::phdr_size;
off_t all_phdrs_size = this->segment_list_.size() * phdr_size;
gold_assert(all_phdrs_size == this->data_size());
unsigned char* view = of->get_output_view(this->offset(),
all_phdrs_size);
unsigned char* v = view;
for (Layout::Segment_list::const_iterator p = this->segment_list_.begin();
p != this->segment_list_.end();
++p)
{
elfcpp::Phdr_write<size, big_endian> ophdr(v);
(*p)->write_header(&ophdr);
v += phdr_size;
}
gold_assert(v - view == all_phdrs_size);
of->write_output_view(this->offset(), all_phdrs_size, view);
}
off_t
Output_segment_headers::do_size() const
{
const int size = parameters->target().get_size();
int phdr_size;
if (size == 32)
phdr_size = elfcpp::Elf_sizes<32>::phdr_size;
else if (size == 64)
phdr_size = elfcpp::Elf_sizes<64>::phdr_size;
else
gold_unreachable();
return this->segment_list_.size() * phdr_size;
}
// Output_file_header methods.
Output_file_header::Output_file_header(Target* target,
const Symbol_table* symtab,
const Output_segment_headers* osh)
: target_(target),
symtab_(symtab),
segment_header_(osh),
section_header_(NULL),
shstrtab_(NULL)
{
this->set_data_size(this->do_size());
}
// Set the section table information for a file header.
void
Output_file_header::set_section_info(const Output_section_headers* shdrs,
const Output_section* shstrtab)
{
this->section_header_ = shdrs;
this->shstrtab_ = shstrtab;
}
// Write out the file header.
void
Output_file_header::do_write(Output_file* of)
{
gold_assert(this->offset() == 0);
switch (parameters->size_and_endianness())
{
#ifdef HAVE_TARGET_32_LITTLE
case Parameters::TARGET_32_LITTLE:
this->do_sized_write<32, false>(of);
break;
#endif
#ifdef HAVE_TARGET_32_BIG
case Parameters::TARGET_32_BIG:
this->do_sized_write<32, true>(of);
break;
#endif
#ifdef HAVE_TARGET_64_LITTLE
case Parameters::TARGET_64_LITTLE:
this->do_sized_write<64, false>(of);
break;
#endif
#ifdef HAVE_TARGET_64_BIG
case Parameters::TARGET_64_BIG:
this->do_sized_write<64, true>(of);
break;
#endif
default:
gold_unreachable();
}
}
// Write out the file header with appropriate size and endianness.
template<int size, bool big_endian>
void
Output_file_header::do_sized_write(Output_file* of)
{
gold_assert(this->offset() == 0);
int ehdr_size = elfcpp::Elf_sizes<size>::ehdr_size;
unsigned char* view = of->get_output_view(0, ehdr_size);
elfcpp::Ehdr_write<size, big_endian> oehdr(view);
unsigned char e_ident[elfcpp::EI_NIDENT];
memset(e_ident, 0, elfcpp::EI_NIDENT);
e_ident[elfcpp::EI_MAG0] = elfcpp::ELFMAG0;
e_ident[elfcpp::EI_MAG1] = elfcpp::ELFMAG1;
e_ident[elfcpp::EI_MAG2] = elfcpp::ELFMAG2;
e_ident[elfcpp::EI_MAG3] = elfcpp::ELFMAG3;
if (size == 32)
e_ident[elfcpp::EI_CLASS] = elfcpp::ELFCLASS32;
else if (size == 64)
e_ident[elfcpp::EI_CLASS] = elfcpp::ELFCLASS64;
else
gold_unreachable();
e_ident[elfcpp::EI_DATA] = (big_endian
? elfcpp::ELFDATA2MSB
: elfcpp::ELFDATA2LSB);
e_ident[elfcpp::EI_VERSION] = elfcpp::EV_CURRENT;
oehdr.put_e_ident(e_ident);
elfcpp::ET e_type;
if (parameters->options().relocatable())
e_type = elfcpp::ET_REL;
else if (parameters->options().output_is_position_independent())
e_type = elfcpp::ET_DYN;
else
e_type = elfcpp::ET_EXEC;
oehdr.put_e_type(e_type);
oehdr.put_e_machine(this->target_->machine_code());
oehdr.put_e_version(elfcpp::EV_CURRENT);
oehdr.put_e_entry(this->entry<size>());
if (this->segment_header_ == NULL)
oehdr.put_e_phoff(0);
else
oehdr.put_e_phoff(this->segment_header_->offset());
oehdr.put_e_shoff(this->section_header_->offset());
oehdr.put_e_flags(this->target_->processor_specific_flags());
oehdr.put_e_ehsize(elfcpp::Elf_sizes<size>::ehdr_size);
if (this->segment_header_ == NULL)
{
oehdr.put_e_phentsize(0);
oehdr.put_e_phnum(0);
}
else
{
oehdr.put_e_phentsize(elfcpp::Elf_sizes<size>::phdr_size);
size_t phnum = (this->segment_header_->data_size()
/ elfcpp::Elf_sizes<size>::phdr_size);
if (phnum > elfcpp::PN_XNUM)
phnum = elfcpp::PN_XNUM;
oehdr.put_e_phnum(phnum);
}
oehdr.put_e_shentsize(elfcpp::Elf_sizes<size>::shdr_size);
size_t section_count = (this->section_header_->data_size()
/ elfcpp::Elf_sizes<size>::shdr_size);
if (section_count < elfcpp::SHN_LORESERVE)
oehdr.put_e_shnum(this->section_header_->data_size()
/ elfcpp::Elf_sizes<size>::shdr_size);
else
oehdr.put_e_shnum(0);
unsigned int shstrndx = this->shstrtab_->out_shndx();
if (shstrndx < elfcpp::SHN_LORESERVE)
oehdr.put_e_shstrndx(this->shstrtab_->out_shndx());
else
oehdr.put_e_shstrndx(elfcpp::SHN_XINDEX);
// Let the target adjust the ELF header, e.g., to set EI_OSABI in
// the e_ident field.
this->target_->adjust_elf_header(view, ehdr_size);
of->write_output_view(0, ehdr_size, view);
}
// Return the value to use for the entry address.
template<int size>
typename elfcpp::Elf_types<size>::Elf_Addr
Output_file_header::entry()
{
const bool should_issue_warning = (parameters->options().entry() != NULL
&& !parameters->options().relocatable()
&& !parameters->options().shared());
const char* entry = parameters->entry();
Symbol* sym = this->symtab_->lookup(entry);
typename Sized_symbol<size>::Value_type v;
if (sym != NULL)
{
Sized_symbol<size>* ssym;
ssym = this->symtab_->get_sized_symbol<size>(sym);
if (!ssym->is_defined() && should_issue_warning)
gold_warning("entry symbol '%s' exists but is not defined", entry);
v = ssym->value();
}
else
{
// We couldn't find the entry symbol. See if we can parse it as
// a number. This supports, e.g., -e 0x1000.
char* endptr;
v = strtoull(entry, &endptr, 0);
if (*endptr != '\0')
{
if (should_issue_warning)
gold_warning("cannot find entry symbol '%s'", entry);
v = 0;
}
}
return v;
}
// Compute the current data size.
off_t
Output_file_header::do_size() const
{
const int size = parameters->target().get_size();
if (size == 32)
return elfcpp::Elf_sizes<32>::ehdr_size;
else if (size == 64)
return elfcpp::Elf_sizes<64>::ehdr_size;
else
gold_unreachable();
}
// Output_data_const methods.
void
Output_data_const::do_write(Output_file* of)
{
of->write(this->offset(), this->data_.data(), this->data_.size());
}
// Output_data_const_buffer methods.
void
Output_data_const_buffer::do_write(Output_file* of)
{
of->write(this->offset(), this->p_, this->data_size());
}
// Output_section_data methods.
// Record the output section, and set the entry size and such.
void
Output_section_data::set_output_section(Output_section* os)
{
gold_assert(this->output_section_ == NULL);
this->output_section_ = os;
this->do_adjust_output_section(os);
}
// Return the section index of the output section.
unsigned int
Output_section_data::do_out_shndx() const
{
gold_assert(this->output_section_ != NULL);
return this->output_section_->out_shndx();
}
// Set the alignment, which means we may need to update the alignment
// of the output section.
void
Output_section_data::set_addralign(uint64_t addralign)
{
this->addralign_ = addralign;
if (this->output_section_ != NULL
&& this->output_section_->addralign() < addralign)
this->output_section_->set_addralign(addralign);
}
// Output_data_strtab methods.
// Set the final data size.
void
Output_data_strtab::set_final_data_size()
{
this->strtab_->set_string_offsets();
this->set_data_size(this->strtab_->get_strtab_size());
}
// Write out a string table.
void
Output_data_strtab::do_write(Output_file* of)
{
this->strtab_->write(of, this->offset());
}
// Output_reloc methods.
// A reloc against a global symbol.
template<bool dynamic, int size, bool big_endian>
Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::Output_reloc(
Symbol* gsym,
unsigned int type,
Output_data* od,
Address address,
bool is_relative,
bool is_symbolless,
bool use_plt_offset)
: address_(address), local_sym_index_(GSYM_CODE), type_(type),
is_relative_(is_relative), is_symbolless_(is_symbolless),
is_section_symbol_(false), use_plt_offset_(use_plt_offset), shndx_(INVALID_CODE)
{
// this->type_ is a bitfield; make sure TYPE fits.
gold_assert(this->type_ == type);
this->u1_.gsym = gsym;
this->u2_.od = od;
if (dynamic)
this->set_needs_dynsym_index();
}
template<bool dynamic, int size, bool big_endian>
Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::Output_reloc(
Symbol* gsym,
unsigned int type,
Sized_relobj<size, big_endian>* relobj,
unsigned int shndx,
Address address,
bool is_relative,
bool is_symbolless,
bool use_plt_offset)
: address_(address), local_sym_index_(GSYM_CODE), type_(type),
is_relative_(is_relative), is_symbolless_(is_symbolless),
is_section_symbol_(false), use_plt_offset_(use_plt_offset), shndx_(shndx)
{
gold_assert(shndx != INVALID_CODE);
// this->type_ is a bitfield; make sure TYPE fits.
gold_assert(this->type_ == type);
this->u1_.gsym = gsym;
this->u2_.relobj = relobj;
if (dynamic)
this->set_needs_dynsym_index();
}
// A reloc against a local symbol.
template<bool dynamic, int size, bool big_endian>
Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::Output_reloc(
Sized_relobj<size, big_endian>* relobj,
unsigned int local_sym_index,
unsigned int type,
Output_data* od,
Address address,
bool is_relative,
bool is_symbolless,
bool is_section_symbol,
bool use_plt_offset)
: address_(address), local_sym_index_(local_sym_index), type_(type),
is_relative_(is_relative), is_symbolless_(is_symbolless),
is_section_symbol_(is_section_symbol), use_plt_offset_(use_plt_offset),
shndx_(INVALID_CODE)
{
gold_assert(local_sym_index != GSYM_CODE
&& local_sym_index != INVALID_CODE);
// this->type_ is a bitfield; make sure TYPE fits.
gold_assert(this->type_ == type);
this->u1_.relobj = relobj;
this->u2_.od = od;
if (dynamic)
this->set_needs_dynsym_index();
}
template<bool dynamic, int size, bool big_endian>
Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::Output_reloc(
Sized_relobj<size, big_endian>* relobj,
unsigned int local_sym_index,
unsigned int type,
unsigned int shndx,
Address address,
bool is_relative,
bool is_symbolless,
bool is_section_symbol,
bool use_plt_offset)
: address_(address), local_sym_index_(local_sym_index), type_(type),
is_relative_(is_relative), is_symbolless_(is_symbolless),
is_section_symbol_(is_section_symbol), use_plt_offset_(use_plt_offset),
shndx_(shndx)
{
gold_assert(local_sym_index != GSYM_CODE
&& local_sym_index != INVALID_CODE);
gold_assert(shndx != INVALID_CODE);
// this->type_ is a bitfield; make sure TYPE fits.
gold_assert(this->type_ == type);
this->u1_.relobj = relobj;
this->u2_.relobj = relobj;
if (dynamic)
this->set_needs_dynsym_index();
}
// A reloc against the STT_SECTION symbol of an output section.
template<bool dynamic, int size, bool big_endian>
Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::Output_reloc(
Output_section* os,
unsigned int type,
Output_data* od,
Address address,
bool is_relative)
: address_(address), local_sym_index_(SECTION_CODE), type_(type),
is_relative_(is_relative), is_symbolless_(is_relative),
is_section_symbol_(true), use_plt_offset_(false), shndx_(INVALID_CODE)
{
// this->type_ is a bitfield; make sure TYPE fits.
gold_assert(this->type_ == type);
this->u1_.os = os;
this->u2_.od = od;
if (dynamic)
this->set_needs_dynsym_index();
else
os->set_needs_symtab_index();
}
template<bool dynamic, int size, bool big_endian>
Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::Output_reloc(
Output_section* os,
unsigned int type,
Sized_relobj<size, big_endian>* relobj,
unsigned int shndx,
Address address,
bool is_relative)
: address_(address), local_sym_index_(SECTION_CODE), type_(type),
is_relative_(is_relative), is_symbolless_(is_relative),
is_section_symbol_(true), use_plt_offset_(false), shndx_(shndx)
{
gold_assert(shndx != INVALID_CODE);
// this->type_ is a bitfield; make sure TYPE fits.
gold_assert(this->type_ == type);
this->u1_.os = os;
this->u2_.relobj = relobj;
if (dynamic)
this->set_needs_dynsym_index();
else
os->set_needs_symtab_index();
}
// An absolute or relative relocation.
template<bool dynamic, int size, bool big_endian>
Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::Output_reloc(
unsigned int type,
Output_data* od,
Address address,
bool is_relative)
: address_(address), local_sym_index_(0), type_(type),
is_relative_(is_relative), is_symbolless_(false),
is_section_symbol_(false), use_plt_offset_(false), shndx_(INVALID_CODE)
{
// this->type_ is a bitfield; make sure TYPE fits.
gold_assert(this->type_ == type);
this->u1_.relobj = NULL;
this->u2_.od = od;
}
template<bool dynamic, int size, bool big_endian>
Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::Output_reloc(
unsigned int type,
Sized_relobj<size, big_endian>* relobj,
unsigned int shndx,
Address address,
bool is_relative)
: address_(address), local_sym_index_(0), type_(type),
is_relative_(is_relative), is_symbolless_(false),
is_section_symbol_(false), use_plt_offset_(false), shndx_(shndx)
{
gold_assert(shndx != INVALID_CODE);
// this->type_ is a bitfield; make sure TYPE fits.
gold_assert(this->type_ == type);
this->u1_.relobj = NULL;
this->u2_.relobj = relobj;
}
// A target specific relocation.
template<bool dynamic, int size, bool big_endian>
Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::Output_reloc(
unsigned int type,
void* arg,
Output_data* od,
Address address)
: address_(address), local_sym_index_(TARGET_CODE), type_(type),
is_relative_(false), is_symbolless_(false),
is_section_symbol_(false), use_plt_offset_(false), shndx_(INVALID_CODE)
{
// this->type_ is a bitfield; make sure TYPE fits.
gold_assert(this->type_ == type);
this->u1_.arg = arg;
this->u2_.od = od;
}
template<bool dynamic, int size, bool big_endian>
Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::Output_reloc(
unsigned int type,
void* arg,
Sized_relobj<size, big_endian>* relobj,
unsigned int shndx,
Address address)
: address_(address), local_sym_index_(TARGET_CODE), type_(type),
is_relative_(false), is_symbolless_(false),
is_section_symbol_(false), use_plt_offset_(false), shndx_(shndx)
{
gold_assert(shndx != INVALID_CODE);
// this->type_ is a bitfield; make sure TYPE fits.
gold_assert(this->type_ == type);
this->u1_.arg = arg;
this->u2_.relobj = relobj;
}
// Record that we need a dynamic symbol index for this relocation.
template<bool dynamic, int size, bool big_endian>
void
Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::
set_needs_dynsym_index()
{
if (this->is_symbolless_)
return;
switch (this->local_sym_index_)
{
case INVALID_CODE:
gold_unreachable();
case GSYM_CODE:
this->u1_.gsym->set_needs_dynsym_entry();
break;
case SECTION_CODE:
this->u1_.os->set_needs_dynsym_index();
break;
case TARGET_CODE:
// The target must take care of this if necessary.
break;
case 0:
break;
default:
{
const unsigned int lsi = this->local_sym_index_;
Sized_relobj_file<size, big_endian>* relobj =
this->u1_.relobj->sized_relobj();
gold_assert(relobj != NULL);
if (!this->is_section_symbol_)
relobj->set_needs_output_dynsym_entry(lsi);
else
relobj->output_section(lsi)->set_needs_dynsym_index();
}
break;
}
}
// Get the symbol index of a relocation.
template<bool dynamic, int size, bool big_endian>
unsigned int
Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::get_symbol_index()
const
{
unsigned int index;
if (this->is_symbolless_)
return 0;
switch (this->local_sym_index_)
{
case INVALID_CODE:
gold_unreachable();
case GSYM_CODE:
if (this->u1_.gsym == NULL)
index = 0;
else if (dynamic)
index = this->u1_.gsym->dynsym_index();
else
index = this->u1_.gsym->symtab_index();
break;
case SECTION_CODE:
if (dynamic)
index = this->u1_.os->dynsym_index();
else
index = this->u1_.os->symtab_index();
break;
case TARGET_CODE:
index = parameters->target().reloc_symbol_index(this->u1_.arg,
this->type_);
break;
case 0:
// Relocations without symbols use a symbol index of 0.
index = 0;
break;
default:
{
const unsigned int lsi = this->local_sym_index_;
Sized_relobj_file<size, big_endian>* relobj =
this->u1_.relobj->sized_relobj();
gold_assert(relobj != NULL);
if (!this->is_section_symbol_)
{
if (dynamic)
index = relobj->dynsym_index(lsi);
else
index = relobj->symtab_index(lsi);
}
else
{
Output_section* os = relobj->output_section(lsi);
gold_assert(os != NULL);
if (dynamic)
index = os->dynsym_index();
else
index = os->symtab_index();
}
}
break;
}
gold_assert(index != -1U);
return index;
}
// For a local section symbol, get the address of the offset ADDEND
// within the input section.
template<bool dynamic, int size, bool big_endian>
typename elfcpp::Elf_types<size>::Elf_Addr
Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::
local_section_offset(Addend addend) const
{
gold_assert(this->local_sym_index_ != GSYM_CODE
&& this->local_sym_index_ != SECTION_CODE
&& this->local_sym_index_ != TARGET_CODE
&& this->local_sym_index_ != INVALID_CODE
&& this->local_sym_index_ != 0
&& this->is_section_symbol_);
const unsigned int lsi = this->local_sym_index_;
Output_section* os = this->u1_.relobj->output_section(lsi);
gold_assert(os != NULL);
Address offset = this->u1_.relobj->get_output_section_offset(lsi);
if (offset != invalid_address)
return offset + addend;
// This is a merge section.
Sized_relobj_file<size, big_endian>* relobj =
this->u1_.relobj->sized_relobj();
gold_assert(relobj != NULL);
offset = os->output_address(relobj, lsi, addend);
gold_assert(offset != invalid_address);
return offset;
}
// Get the output address of a relocation.
template<bool dynamic, int size, bool big_endian>
typename elfcpp::Elf_types<size>::Elf_Addr
Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::get_address() const
{
Address address = this->address_;
if (this->shndx_ != INVALID_CODE)
{
Output_section* os = this->u2_.relobj->output_section(this->shndx_);
gold_assert(os != NULL);
Address off = this->u2_.relobj->get_output_section_offset(this->shndx_);
if (off != invalid_address)
address += os->address() + off;
else
{
Sized_relobj_file<size, big_endian>* relobj =
this->u2_.relobj->sized_relobj();
gold_assert(relobj != NULL);
address = os->output_address(relobj, this->shndx_, address);
gold_assert(address != invalid_address);
}
}
else if (this->u2_.od != NULL)
address += this->u2_.od->address();
return address;
}
// Write out the offset and info fields of a Rel or Rela relocation
// entry.
template<bool dynamic, int size, bool big_endian>
template<typename Write_rel>
void
Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::write_rel(
Write_rel* wr) const
{
wr->put_r_offset(this->get_address());
unsigned int sym_index = this->get_symbol_index();
wr->put_r_info(elfcpp::elf_r_info<size>(sym_index, this->type_));
}
// Write out a Rel relocation.
template<bool dynamic, int size, bool big_endian>
void
Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::write(
unsigned char* pov) const
{
elfcpp::Rel_write<size, big_endian> orel(pov);
this->write_rel(&orel);
}
// Get the value of the symbol referred to by a Rel relocation.
template<bool dynamic, int size, bool big_endian>
typename elfcpp::Elf_types<size>::Elf_Addr
Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::symbol_value(
Addend addend) const
{
if (this->local_sym_index_ == GSYM_CODE)
{
const Sized_symbol<size>* sym;
sym = static_cast<const Sized_symbol<size>*>(this->u1_.gsym);
if (this->use_plt_offset_ && sym->has_plt_offset())
return parameters->target().plt_address_for_global(sym);
else
return sym->value() + addend;
}
if (this->local_sym_index_ == SECTION_CODE)
{
gold_assert(!this->use_plt_offset_);
return this->u1_.os->address() + addend;
}
gold_assert(this->local_sym_index_ != TARGET_CODE
&& this->local_sym_index_ != INVALID_CODE
&& this->local_sym_index_ != 0
&& !this->is_section_symbol_);
const unsigned int lsi = this->local_sym_index_;
Sized_relobj_file<size, big_endian>* relobj =
this->u1_.relobj->sized_relobj();
gold_assert(relobj != NULL);
if (this->use_plt_offset_)
return parameters->target().plt_address_for_local(relobj, lsi);
const Symbol_value<size>* symval = relobj->local_symbol(lsi);
return symval->value(relobj, addend);
}
// Reloc comparison. This function sorts the dynamic relocs for the
// benefit of the dynamic linker. First we sort all relative relocs
// to the front. Among relative relocs, we sort by output address.
// Among non-relative relocs, we sort by symbol index, then by output
// address.
template<bool dynamic, int size, bool big_endian>
int
Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::
compare(const Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>& r2)
const
{
if (this->is_relative_)
{
if (!r2.is_relative_)
return -1;
// Otherwise sort by reloc address below.
}
else if (r2.is_relative_)
return 1;
else
{
unsigned int sym1 = this->get_symbol_index();
unsigned int sym2 = r2.get_symbol_index();
if (sym1 < sym2)
return -1;
else if (sym1 > sym2)
return 1;
// Otherwise sort by reloc address.
}
section_offset_type addr1 = this->get_address();
section_offset_type addr2 = r2.get_address();
if (addr1 < addr2)
return -1;
else if (addr1 > addr2)
return 1;
// Final tie breaker, in order to generate the same output on any
// host: reloc type.
unsigned int type1 = this->type_;
unsigned int type2 = r2.type_;
if (type1 < type2)
return -1;
else if (type1 > type2)
return 1;
// These relocs appear to be exactly the same.
return 0;
}
// Write out a Rela relocation.
template<bool dynamic, int size, bool big_endian>
void
Output_reloc<elfcpp::SHT_RELA, dynamic, size, big_endian>::write(
unsigned char* pov) const
{
elfcpp::Rela_write<size, big_endian> orel(pov);
this->rel_.write_rel(&orel);
Addend addend = this->addend_;
if (this->rel_.is_target_specific())
addend = parameters->target().reloc_addend(this->rel_.target_arg(),
this->rel_.type(), addend);
else if (this->rel_.is_symbolless())
addend = this->rel_.symbol_value(addend);
else if (this->rel_.is_local_section_symbol())
addend = this->rel_.local_section_offset(addend);
orel.put_r_addend(addend);
}
// Output_data_reloc_base methods.
// Adjust the output section.
template<int sh_type, bool dynamic, int size, bool big_endian>
void
Output_data_reloc_base<sh_type, dynamic, size, big_endian>
::do_adjust_output_section(Output_section* os)
{
if (sh_type == elfcpp::SHT_REL)
os->set_entsize(elfcpp::Elf_sizes<size>::rel_size);
else if (sh_type == elfcpp::SHT_RELA)
os->set_entsize(elfcpp::Elf_sizes<size>::rela_size);
else
gold_unreachable();
// A STT_GNU_IFUNC symbol may require a IRELATIVE reloc when doing a
// static link. The backends will generate a dynamic reloc section
// to hold this. In that case we don't want to link to the dynsym
// section, because there isn't one.
if (!dynamic)
os->set_should_link_to_symtab();
else if (parameters->doing_static_link())
;
else
os->set_should_link_to_dynsym();
}
// Standard relocation writer, which just calls Output_reloc::write().
template<int sh_type, bool dynamic, int size, bool big_endian>
struct Output_reloc_writer
{
typedef Output_reloc<sh_type, dynamic, size, big_endian> Output_reloc_type;
typedef std::vector<Output_reloc_type> Relocs;
static void
write(typename Relocs::const_iterator p, unsigned char* pov)
{ p->write(pov); }
};
// Write out relocation data.
template<int sh_type, bool dynamic, int size, bool big_endian>
void
Output_data_reloc_base<sh_type, dynamic, size, big_endian>::do_write(
Output_file* of)
{
typedef Output_reloc_writer<sh_type, dynamic, size, big_endian> Writer;
this->do_write_generic<Writer>(of);
}
// Class Output_relocatable_relocs.
template<int sh_type, int size, bool big_endian>
void
Output_relocatable_relocs<sh_type, size, big_endian>::set_final_data_size()
{
this->set_data_size(this->rr_->output_reloc_count()
* Reloc_types<sh_type, size, big_endian>::reloc_size);
}
// class Output_data_group.
template<int size, bool big_endian>
Output_data_group<size, big_endian>::Output_data_group(
Sized_relobj_file<size, big_endian>* relobj,
section_size_type entry_count,
elfcpp::Elf_Word flags,
std::vector<unsigned int>* input_shndxes)
: Output_section_data(entry_count * 4, 4, false),
relobj_(relobj),
flags_(flags)
{
this->input_shndxes_.swap(*input_shndxes);
}
// Write out the section group, which means translating the section
// indexes to apply to the output file.
template<int size, bool big_endian>
void
Output_data_group<size, big_endian>::do_write(Output_file* of)
{
const off_t off = this->offset();
const section_size_type oview_size =
convert_to_section_size_type(this->data_size());
unsigned char* const oview = of->get_output_view(off, oview_size);
elfcpp::Elf_Word* contents = reinterpret_cast<elfcpp::Elf_Word*>(oview);
elfcpp::Swap<32, big_endian>::writeval(contents, this->flags_);
++contents;
for (std::vector<unsigned int>::const_iterator p =
this->input_shndxes_.begin();
p != this->input_shndxes_.end();
++p, ++contents)
{
Output_section* os = this->relobj_->output_section(*p);
unsigned int output_shndx;
if (os != NULL)
output_shndx = os->out_shndx();
else
{
this->relobj_->error(_("section group retained but "
"group element discarded"));
output_shndx = 0;
}
elfcpp::Swap<32, big_endian>::writeval(contents, output_shndx);
}
size_t wrote = reinterpret_cast<unsigned char*>(contents) - oview;
gold_assert(wrote == oview_size);
of->write_output_view(off, oview_size, oview);
// We no longer need this information.
this->input_shndxes_.clear();
}
// Output_data_got::Got_entry methods.
// Write out the entry.
template<int got_size, bool big_endian>
void
Output_data_got<got_size, big_endian>::Got_entry::write(
unsigned int got_indx,
unsigned char* pov) const
{
Valtype val = 0;
switch (this->local_sym_index_)
{
case GSYM_CODE:
{
// If the symbol is resolved locally, we need to write out the
// link-time value, which will be relocated dynamically by a
// RELATIVE relocation.
Symbol* gsym = this->u_.gsym;
if (this->use_plt_or_tls_offset_ && gsym->has_plt_offset())
val = parameters->target().plt_address_for_global(gsym);
else
{
switch (parameters->size_and_endianness())
{
#if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
case Parameters::TARGET_32_LITTLE:
case Parameters::TARGET_32_BIG:
{
// This cast is ugly. We don't want to put a
// virtual method in Symbol, because we want Symbol
// to be as small as possible.
Sized_symbol<32>::Value_type v;
v = static_cast<Sized_symbol<32>*>(gsym)->value();
val = convert_types<Valtype, Sized_symbol<32>::Value_type>(v);
}
break;
#endif
#if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
case Parameters::TARGET_64_LITTLE:
case Parameters::TARGET_64_BIG:
{
Sized_symbol<64>::Value_type v;
v = static_cast<Sized_symbol<64>*>(gsym)->value();
val = convert_types<Valtype, Sized_symbol<64>::Value_type>(v);
}
break;
#endif
default:
gold_unreachable();
}
if (this->use_plt_or_tls_offset_
&& gsym->type() == elfcpp::STT_TLS)
val += parameters->target().tls_offset_for_global(gsym,
got_indx);
}
}
break;
case CONSTANT_CODE:
val = this->u_.constant;
break;
case RESERVED_CODE:
// If we're doing an incremental update, don't touch this GOT entry.
if (parameters->incremental_update())
return;
val = this->u_.constant;
break;
default:
{
const Relobj* object = this->u_.object;
const unsigned int lsi = this->local_sym_index_;
bool is_tls = object->local_is_tls(lsi);
if (this->use_plt_or_tls_offset_ && !is_tls)
val = parameters->target().plt_address_for_local(object, lsi);
else
{
uint64_t lval = object->local_symbol_value(lsi, this->addend_);
val = convert_types<Valtype, uint64_t>(lval);
if (this->use_plt_or_tls_offset_ && is_tls)
val += parameters->target().tls_offset_for_local(object, lsi,
got_indx);
}
}
break;
}
elfcpp::Swap<got_size, big_endian>::writeval(pov, val);
}
// Output_data_got methods.
// Add an entry for a global symbol to the GOT. This returns true if
// this is a new GOT entry, false if the symbol already had a GOT
// entry.
template<int got_size, bool big_endian>
bool
Output_data_got<got_size, big_endian>::add_global(
Symbol* gsym,
unsigned int got_type)
{
if (gsym->has_got_offset(got_type))
return false;
unsigned int got_offset = this->add_got_entry(Got_entry(gsym, false));
gsym->set_got_offset(got_type, got_offset);
return true;
}
// Like add_global, but use the PLT offset.
template<int got_size, bool big_endian>
bool
Output_data_got<got_size, big_endian>::add_global_plt(Symbol* gsym,
unsigned int got_type)
{
if (gsym->has_got_offset(got_type))
return false;
unsigned int got_offset = this->add_got_entry(Got_entry(gsym, true));
gsym->set_got_offset(got_type, got_offset);
return true;
}
// Add an entry for a global symbol to the GOT, and add a dynamic
// relocation of type R_TYPE for the GOT entry.
template<int got_size, bool big_endian>
void
Output_data_got<got_size, big_endian>::add_global_with_rel(
Symbol* gsym,
unsigned int got_type,
Output_data_reloc_generic* rel_dyn,
unsigned int r_type)
{
if (gsym->has_got_offset(got_type))
return;
unsigned int got_offset = this->add_got_entry(Got_entry());
gsym->set_got_offset(got_type, got_offset);
rel_dyn->add_global_generic(gsym, r_type, this, got_offset, 0);
}
// Add a pair of entries for a global symbol to the GOT, and add
// dynamic relocations of type R_TYPE_1 and R_TYPE_2, respectively.
// If R_TYPE_2 == 0, add the second entry with no relocation.
template<int got_size, bool big_endian>
void
Output_data_got<got_size, big_endian>::add_global_pair_with_rel(
Symbol* gsym,
unsigned int got_type,
Output_data_reloc_generic* rel_dyn,
unsigned int r_type_1,
unsigned int r_type_2)
{
if (gsym->has_got_offset(got_type))
return;
unsigned int got_offset = this->add_got_entry_pair(Got_entry(), Got_entry());
gsym->set_got_offset(got_type, got_offset);
rel_dyn->add_global_generic(gsym, r_type_1, this, got_offset, 0);
if (r_type_2 != 0)
rel_dyn->add_global_generic(gsym, r_type_2, this,
got_offset + got_size / 8, 0);
}
// Add an entry for a local symbol to the GOT. This returns true if
// this is a new GOT entry, false if the symbol already has a GOT
// entry.
template<int got_size, bool big_endian>
bool
Output_data_got<got_size, big_endian>::add_local(
Relobj* object,
unsigned int symndx,
unsigned int got_type)
{
if (object->local_has_got_offset(symndx, got_type))
return false;
unsigned int got_offset = this->add_got_entry(Got_entry(object, symndx,
false));
object->set_local_got_offset(symndx, got_type, got_offset);
return true;
}
// Add an entry for a local symbol plus ADDEND to the GOT. This returns
// true if this is a new GOT entry, false if the symbol already has a GOT
// entry.
template<int got_size, bool big_endian>
bool
Output_data_got<got_size, big_endian>::add_local(
Relobj* object,
unsigned int symndx,
unsigned int got_type,
uint64_t addend)
{
if (object->local_has_got_offset(symndx, got_type, addend))
return false;
unsigned int got_offset = this->add_got_entry(Got_entry(object, symndx,
false, addend));
object->set_local_got_offset(symndx, got_type, got_offset, addend);
return true;
}
// Like add_local, but use the PLT offset.
template<int got_size, bool big_endian>
bool
Output_data_got<got_size, big_endian>::add_local_plt(
Relobj* object,
unsigned int symndx,
unsigned int got_type)
{
if (object->local_has_got_offset(symndx, got_type))
return false;
unsigned int got_offset = this->add_got_entry(Got_entry(object, symndx,
true));
object->set_local_got_offset(symndx, got_type, got_offset);
return true;
}
// Add an entry for a local symbol to the GOT, and add a dynamic
// relocation of type R_TYPE for the GOT entry.
template<int got_size, bool big_endian>
void
Output_data_got<got_size, big_endian>::add_local_with_rel(
Relobj* object,
unsigned int symndx,
unsigned int got_type,
Output_data_reloc_generic* rel_dyn,
unsigned int r_type)
{
if (object->local_has_got_offset(symndx, got_type))
return;
unsigned int got_offset = this->add_got_entry(Got_entry());
object->set_local_got_offset(symndx, got_type, got_offset);
rel_dyn->add_local_generic(object, symndx, r_type, this, got_offset, 0);
}
// Add an entry for a local symbol plus ADDEND to the GOT, and add a dynamic
// relocation of type R_TYPE for the GOT entry.
template<int got_size, bool big_endian>
void
Output_data_got<got_size, big_endian>::add_local_with_rel(
Relobj* object,
unsigned int symndx,
unsigned int got_type,
Output_data_reloc_generic* rel_dyn,
unsigned int r_type, uint64_t addend)
{
if (object->local_has_got_offset(symndx, got_type, addend))
return;
unsigned int got_offset = this->add_got_entry(Got_entry());
object->set_local_got_offset(symndx, got_type, got_offset, addend);
rel_dyn->add_local_generic(object, symndx, r_type, this, got_offset,
addend);
}
// Add a pair of entries for a local symbol to the GOT, and add
// a dynamic relocation of type R_TYPE using the section symbol of
// the output section to which input section SHNDX maps, on the first.
// The first got entry will have a value of zero, the second the
// value of the local symbol.
template<int got_size, bool big_endian>
void
Output_data_got<got_size, big_endian>::add_local_pair_with_rel(
Relobj* object,
unsigned int symndx,
unsigned int shndx,
unsigned int got_type,
Output_data_reloc_generic* rel_dyn,
unsigned int r_type)
{
if (object->local_has_got_offset(symndx, got_type))
return;
unsigned int got_offset =
this->add_got_entry_pair(Got_entry(),
Got_entry(object, symndx, false));
object->set_local_got_offset(symndx, got_type, got_offset);
Output_section* os = object->output_section(shndx);
rel_dyn->add_output_section_generic(os, r_type, this, got_offset, 0);
}
// Add a pair of entries for a local symbol plus ADDEND to the GOT, and add
// a dynamic relocation of type R_TYPE using the section symbol of
// the output section to which input section SHNDX maps, on the first.
// The first got entry will have a value of zero, the second the
// value of the local symbol.
template<int got_size, bool big_endian>
void
Output_data_got<got_size, big_endian>::add_local_pair_with_rel(
Relobj* object,
unsigned int symndx,
unsigned int shndx,
unsigned int got_type,
Output_data_reloc_generic* rel_dyn,
unsigned int r_type, uint64_t addend)
{
if (object->local_has_got_offset(symndx, got_type, addend))
return;
unsigned int got_offset =
this->add_got_entry_pair(Got_entry(),
Got_entry(object, symndx, false, addend));
object->set_local_got_offset(symndx, got_type, got_offset, addend);
Output_section* os = object->output_section(shndx);
rel_dyn->add_output_section_generic(os, r_type, this, got_offset, addend);
}
// Add a pair of entries for a local symbol to the GOT, and add
// a dynamic relocation of type R_TYPE using STN_UNDEF on the first.
// The first got entry will have a value of zero, the second the
// value of the local symbol offset by Target::tls_offset_for_local.
template<int got_size, bool big_endian>
void
Output_data_got<got_size, big_endian>::add_local_tls_pair(
Relobj* object,
unsigned int symndx,
unsigned int got_type,
Output_data_reloc_generic* rel_dyn,
unsigned int r_type)
{
if (object->local_has_got_offset(symndx, got_type))
return;
unsigned int got_offset
= this->add_got_entry_pair(Got_entry(),
Got_entry(object, symndx, true));
object->set_local_got_offset(symndx, got_type, got_offset);
rel_dyn->add_local_generic(object, 0, r_type, this, got_offset, 0);
}
// Reserve a slot in the GOT for a local symbol or the second slot of a pair.
template<int got_size, bool big_endian>
void
Output_data_got<got_size, big_endian>::reserve_local(
unsigned int i,
Relobj* object,
unsigned int sym_index,
unsigned int got_type)
{
this->do_reserve_slot(i);
object->set_local_got_offset(sym_index, got_type, this->got_offset(i));
}
// Reserve a slot in the GOT for a global symbol.
template<int got_size, bool big_endian>
void
Output_data_got<got_size, big_endian>::reserve_global(
unsigned int i,
Symbol* gsym,
unsigned int got_type)
{
this->do_reserve_slot(i);
gsym->set_got_offset(got_type, this->got_offset(i));
}
// Write out the GOT.
template<int got_size, bool big_endian>
void
Output_data_got<got_size, big_endian>::do_write(Output_file* of)
{
const int add = got_size / 8;
const off_t off = this->offset();
const off_t oview_size = this->data_size();
unsigned char* const oview = of->get_output_view(off, oview_size);
unsigned char* pov = oview;
for (unsigned int i = 0; i < this->entries_.size(); ++i)
{
this->entries_[i].write(i, pov);
pov += add;
}
gold_assert(pov - oview == oview_size);
of->write_output_view(off, oview_size, oview);
// We no longer need the GOT entries.
this->entries_.clear();
}
// Create a new GOT entry and return its offset.
template<int got_size, bool big_endian>
unsigned int
Output_data_got<got_size, big_endian>::add_got_entry(Got_entry got_entry)
{
if (!this->is_data_size_valid())
{
this->entries_.push_back(got_entry);
this->set_got_size();
return this->last_got_offset();
}
else
{
// For an incremental update, find an available slot.
off_t got_offset = this->free_list_.allocate(got_size / 8,
got_size / 8, 0);
if (got_offset == -1)
gold_fallback(_("out of patch space (GOT);"
" relink with --incremental-full"));
unsigned int got_index = got_offset / (got_size / 8);
gold_assert(got_index < this->entries_.size());
this->entries_[got_index] = got_entry;
return static_cast<unsigned int>(got_offset);
}
}
// Create a pair of new GOT entries and return the offset of the first.
template<int got_size, bool big_endian>
unsigned int
Output_data_got<got_size, big_endian>::add_got_entry_pair(
Got_entry got_entry_1,
Got_entry got_entry_2)
{
if (!this->is_data_size_valid())
{
unsigned int got_offset;
this->entries_.push_back(got_entry_1);
got_offset = this->last_got_offset();
this->entries_.push_back(got_entry_2);
this->set_got_size();
return got_offset;
}
else
{
// For an incremental update, find an available pair of slots.
off_t got_offset = this->free_list_.allocate(2 * got_size / 8,
got_size / 8, 0);
if (got_offset == -1)
gold_fallback(_("out of patch space (GOT);"
" relink with --incremental-full"));
unsigned int got_index = got_offset / (got_size / 8);
gold_assert(got_index < this->entries_.size());
this->entries_[got_index] = got_entry_1;
this->entries_[got_index + 1] = got_entry_2;
return static_cast<unsigned int>(got_offset);
}
}
// Replace GOT entry I with a new value.
template<int got_size, bool big_endian>
void
Output_data_got<got_size, big_endian>::replace_got_entry(
unsigned int i,
Got_entry got_entry)
{
gold_assert(i < this->entries_.size());
this->entries_[i] = got_entry;
}
// Output_data_dynamic::Dynamic_entry methods.
// Write out the entry.
template<int size, bool big_endian>
void
Output_data_dynamic::Dynamic_entry::write(
unsigned char* pov,
const Stringpool* pool) const
{
typename elfcpp::Elf_types<size>::Elf_WXword val;
switch (this->offset_)
{
case DYNAMIC_NUMBER:
val = this->u_.val;
break;
case DYNAMIC_SECTION_SIZE:
val = this->u_.od->data_size();
if (this->od2 != NULL)
val += this->od2->data_size();
break;
case DYNAMIC_SYMBOL:
{
const Sized_symbol<size>* s =
static_cast<const Sized_symbol<size>*>(this->u_.sym);
val = s->value();
}
break;
case DYNAMIC_STRING:
val = pool->get_offset(this->u_.str);
break;
case DYNAMIC_CUSTOM:
val = parameters->target().dynamic_tag_custom_value(this->tag_);
break;
default:
val = this->u_.od->address() + this->offset_;
break;
}
elfcpp::Dyn_write<size, big_endian> dw(pov);
dw.put_d_tag(this->tag_);
dw.put_d_val(val);
}
// Output_data_dynamic methods.
// Adjust the output section to set the entry size.
void
Output_data_dynamic::do_adjust_output_section(Output_section* os)
{
if (parameters->target().get_size() == 32)
os->set_entsize(elfcpp::Elf_sizes<32>::dyn_size);
else if (parameters->target().get_size() == 64)
os->set_entsize(elfcpp::Elf_sizes<64>::dyn_size);
else
gold_unreachable();
}
// Get a dynamic entry offset.
unsigned int
Output_data_dynamic::get_entry_offset(elfcpp::DT tag) const
{
int dyn_size;
if (parameters->target().get_size() == 32)
dyn_size = elfcpp::Elf_sizes<32>::dyn_size;
else if (parameters->target().get_size() == 64)
dyn_size = elfcpp::Elf_sizes<64>::dyn_size;
else
gold_unreachable();
for (size_t i = 0; i < entries_.size(); ++i)
if (entries_[i].tag() == tag)
return i * dyn_size;
return -1U;
}
// Set the final data size.
void
Output_data_dynamic::set_final_data_size()
{
// Add the terminating entry if it hasn't been added.
// Because of relaxation, we can run this multiple times.
if (this->entries_.empty() || this->entries_.back().tag() != elfcpp::DT_NULL)
{
int extra = parameters->options().spare_dynamic_tags();
for (int i = 0; i < extra; ++i)
this->add_constant(elfcpp::DT_NULL, 0);
this->add_constant(elfcpp::DT_NULL, 0);
}
int dyn_size;
if (parameters->target().get_size() == 32)
dyn_size = elfcpp::Elf_sizes<32>::dyn_size;
else if (parameters->target().get_size() == 64)
dyn_size = elfcpp::Elf_sizes<64>::dyn_size;
else
gold_unreachable();
this->set_data_size(this->entries_.size() * dyn_size);
}
// Write out the dynamic entries.
void
Output_data_dynamic::do_write(Output_file* of)
{
switch (parameters->size_and_endianness())
{
#ifdef HAVE_TARGET_32_LITTLE
case Parameters::TARGET_32_LITTLE:
this->sized_write<32, false>(of);
break;
#endif
#ifdef HAVE_TARGET_32_BIG
case Parameters::TARGET_32_BIG:
this->sized_write<32, true>(of);
break;
#endif
#ifdef HAVE_TARGET_64_LITTLE
case Parameters::TARGET_64_LITTLE:
this->sized_write<64, false>(of);
break;
#endif
#ifdef HAVE_TARGET_64_BIG
case Parameters::TARGET_64_BIG:
this->sized_write<64, true>(of);
break;
#endif
default:
gold_unreachable();
}
}
template<int size, bool big_endian>
void
Output_data_dynamic::sized_write(Output_file* of)
{
const int dyn_size = elfcpp::Elf_sizes<size>::dyn_size;
const off_t offset = this->offset();
const off_t oview_size = this->data_size();
unsigned char* const oview = of->get_output_view(offset, oview_size);
unsigned char* pov = oview;
for (typename Dynamic_entries::const_iterator p = this->entries_.begin();
p != this->entries_.end();
++p)
{
p->write<size, big_endian>(pov, this->pool_);
pov += dyn_size;
}
gold_assert(pov - oview == oview_size);
of->write_output_view(offset, oview_size, oview);
// We no longer need the dynamic entries.
this->entries_.clear();
}
// Class Output_symtab_xindex.
void
Output_symtab_xindex::do_write(Output_file* of)
{
const off_t offset = this->offset();
const off_t oview_size = this->data_size();
unsigned char* const oview = of->get_output_view(offset, oview_size);
memset(oview, 0, oview_size);
if (parameters->target().is_big_endian())
this->endian_do_write<true>(oview);
else
this->endian_do_write<false>(oview);
of->write_output_view(offset, oview_size, oview);
// We no longer need the data.
this->entries_.clear();
}
template<bool big_endian>
void
Output_symtab_xindex::endian_do_write(unsigned char* const oview)
{
for (Xindex_entries::const_iterator p = this->entries_.begin();
p != this->entries_.end();
++p)
{
unsigned int symndx = p->first;
gold_assert(static_cast<off_t>(symndx) * 4 < this->data_size());
elfcpp::Swap<32, big_endian>::writeval(oview + symndx * 4, p->second);
}
}
// Output_fill_debug_info methods.
// Return the minimum size needed for a dummy compilation unit header.
size_t
Output_fill_debug_info::do_minimum_hole_size() const
{
// Compile unit header fields: unit_length, version, debug_abbrev_offset,
// address_size.
const size_t len = 4 + 2 + 4 + 1;
// For type units, add type_signature, type_offset.
if (this->is_debug_types_)
return len + 8 + 4;
return len;
}
// Write a dummy compilation unit header to fill a hole in the
// .debug_info or .debug_types section.
void
Output_fill_debug_info::do_write(Output_file* of, off_t off, size_t len) const
{
gold_debug(DEBUG_INCREMENTAL, "fill_debug_info(%08lx, %08lx)",
static_cast<long>(off), static_cast<long>(len));
gold_assert(len >= this->do_minimum_hole_size());
unsigned char* const oview = of->get_output_view(off, len);
unsigned char* pov = oview;
// Write header fields: unit_length, version, debug_abbrev_offset,
// address_size.
if (this->is_big_endian())
{
elfcpp::Swap_unaligned<32, true>::writeval(pov, len - 4);
elfcpp::Swap_unaligned<16, true>::writeval(pov + 4, this->version);
elfcpp::Swap_unaligned<32, true>::writeval(pov + 6, 0);
}
else
{
elfcpp::Swap_unaligned<32, false>::writeval(pov, len - 4);
elfcpp::Swap_unaligned<16, false>::writeval(pov + 4, this->version);
elfcpp::Swap_unaligned<32, false>::writeval(pov + 6, 0);
}
pov += 4 + 2 + 4;
*pov++ = 4;
// For type units, the additional header fields -- type_signature,
// type_offset -- can be filled with zeroes.
// Fill the remainder of the free space with zeroes. The first
// zero should tell the consumer there are no DIEs to read in this
// compilation unit.
if (pov < oview + len)
memset(pov, 0, oview + len - pov);
of->write_output_view(off, len, oview);
}
// Output_fill_debug_line methods.
// Return the minimum size needed for a dummy line number program header.
size_t
Output_fill_debug_line::do_minimum_hole_size() const
{
// Line number program header fields: unit_length, version, header_length,
// minimum_instruction_length, default_is_stmt, line_base, line_range,
// opcode_base, standard_opcode_lengths[], include_directories, filenames.
const size_t len = 4 + 2 + 4 + this->header_length;
return len;
}
// Write a dummy line number program header to fill a hole in the
// .debug_line section.
void
Output_fill_debug_line::do_write(Output_file* of, off_t off, size_t len) const
{
gold_debug(DEBUG_INCREMENTAL, "fill_debug_line(%08lx, %08lx)",
static_cast<long>(off), static_cast<long>(len));
gold_assert(len >= this->do_minimum_hole_size());
unsigned char* const oview = of->get_output_view(off, len);
unsigned char* pov = oview;
// Write header fields: unit_length, version, header_length,
// minimum_instruction_length, default_is_stmt, line_base, line_range,
// opcode_base, standard_opcode_lengths[], include_directories, filenames.
// We set the header_length field to cover the entire hole, so the
// line number program is empty.
if (this->is_big_endian())
{
elfcpp::Swap_unaligned<32, true>::writeval(pov, len - 4);
elfcpp::Swap_unaligned<16, true>::writeval(pov + 4, this->version);
elfcpp::Swap_unaligned<32, true>::writeval(pov + 6, len - (4 + 2 + 4));
}
else
{
elfcpp::Swap_unaligned<32, false>::writeval(pov, len - 4);
elfcpp::Swap_unaligned<16, false>::writeval(pov + 4, this->version);
elfcpp::Swap_unaligned<32, false>::writeval(pov + 6, len - (4 + 2 + 4));
}
pov += 4 + 2 + 4;
*pov++ = 1; // minimum_instruction_length
*pov++ = 0; // default_is_stmt
*pov++ = 0; // line_base
*pov++ = 5; // line_range
*pov++ = 13; // opcode_base
*pov++ = 0; // standard_opcode_lengths[1]
*pov++ = 1; // standard_opcode_lengths[2]
*pov++ = 1; // standard_opcode_lengths[3]
*pov++ = 1; // standard_opcode_lengths[4]
*pov++ = 1; // standard_opcode_lengths[5]
*pov++ = 0; // standard_opcode_lengths[6]
*pov++ = 0; // standard_opcode_lengths[7]
*pov++ = 0; // standard_opcode_lengths[8]
*pov++ = 1; // standard_opcode_lengths[9]
*pov++ = 0; // standard_opcode_lengths[10]
*pov++ = 0; // standard_opcode_lengths[11]
*pov++ = 1; // standard_opcode_lengths[12]
*pov++ = 0; // include_directories (empty)
*pov++ = 0; // filenames (empty)
// Some consumers don't check the header_length field, and simply
// start reading the line number program immediately following the
// header. For those consumers, we fill the remainder of the free
// space with DW_LNS_set_basic_block opcodes. These are effectively
// no-ops: the resulting line table program will not create any rows.
if (pov < oview + len)
memset(pov, elfcpp::DW_LNS_set_basic_block, oview + len - pov);
of->write_output_view(off, len, oview);
}
// Output_section::Input_section methods.
// Return the current data size. For an input section we store the size here.
// For an Output_section_data, we have to ask it for the size.
off_t
Output_section::Input_section::current_data_size() const
{
if (this->is_input_section())
return this->u1_.data_size;
else
{
this->u2_.posd->pre_finalize_data_size();
return this->u2_.posd->current_data_size();
}
}
// Return the data size. For an input section we store the size here.
// For an Output_section_data, we have to ask it for the size.
off_t
Output_section::Input_section::data_size() const
{
if (this->is_input_section())
return this->u1_.data_size;
else
return this->u2_.posd->data_size();
}
// Return the object for an input section.
Relobj*
Output_section::Input_section::relobj() const
{
if (this->is_input_section())
return this->u2_.object;
else if (this->is_merge_section())
{
gold_assert(this->u2_.pomb->first_relobj() != NULL);
return this->u2_.pomb->first_relobj();
}
else if (this->is_relaxed_input_section())
return this->u2_.poris->relobj();
else
gold_unreachable();
}
// Return the input section index for an input section.
unsigned int
Output_section::Input_section::shndx() const
{
if (this->is_input_section())
return this->shndx_;
else if (this->is_merge_section())
{
gold_assert(this->u2_.pomb->first_relobj() != NULL);
return this->u2_.pomb->first_shndx();
}
else if (this->is_relaxed_input_section())
return this->u2_.poris->shndx();
else
gold_unreachable();
}
// Set the address and file offset.
void
Output_section::Input_section::set_address_and_file_offset(
uint64_t address,
off_t file_offset,
off_t section_file_offset)
{
if (this->is_input_section())
this->u2_.object->set_section_offset(this->shndx_,
file_offset - section_file_offset);
else
this->u2_.posd->set_address_and_file_offset(address, file_offset);
}
// Reset the address and file offset.
void
Output_section::Input_section::reset_address_and_file_offset()
{
if (!this->is_input_section())
this->u2_.posd->reset_address_and_file_offset();
}
// Finalize the data size.
void
Output_section::Input_section::finalize_data_size()
{
if (!this->is_input_section())
this->u2_.posd->finalize_data_size();
}
// Try to turn an input offset into an output offset. We want to
// return the output offset relative to the start of this
// Input_section in the output section.
inline bool
Output_section::Input_section::output_offset(
const Relobj* object,
unsigned int shndx,
section_offset_type offset,
section_offset_type* poutput) const
{
if (!this->is_input_section())
return this->u2_.posd->output_offset(object, shndx, offset, poutput);
else
{
if (this->shndx_ != shndx || this->u2_.object != object)
return false;
*poutput = offset;
return true;
}
}
// Write out the data. We don't have to do anything for an input
// section--they are handled via Object::relocate--but this is where
// we write out the data for an Output_section_data.
void
Output_section::Input_section::write(Output_file* of)
{
if (!this->is_input_section())
this->u2_.posd->write(of);
}
// Write the data to a buffer. As for write(), we don't have to do
// anything for an input section.
void
Output_section::Input_section::write_to_buffer(unsigned char* buffer)
{
if (!this->is_input_section())
this->u2_.posd->write_to_buffer(buffer);
}
// Print to a map file.
void
Output_section::Input_section::print_to_mapfile(Mapfile* mapfile) const
{
switch (this->shndx_)
{
case OUTPUT_SECTION_CODE:
case MERGE_DATA_SECTION_CODE:
case MERGE_STRING_SECTION_CODE:
this->u2_.posd->print_to_mapfile(mapfile);
break;
case RELAXED_INPUT_SECTION_CODE:
{
Output_relaxed_input_section* relaxed_section =
this->relaxed_input_section();
mapfile->print_input_section(relaxed_section->relobj(),
relaxed_section->shndx());
}
break;
default:
mapfile->print_input_section(this->u2_.object, this->shndx_);
break;
}
}
// Output_section methods.
// Construct an Output_section. NAME will point into a Stringpool.
Output_section::Output_section(const char* name, elfcpp::Elf_Word type,
elfcpp::Elf_Xword flags)
: name_(name),
addralign_(0),
entsize_(0),
load_address_(0),
link_section_(NULL),
link_(0),
info_section_(NULL),
info_symndx_(NULL),
info_(0),
type_(type),
flags_(flags),
order_(ORDER_INVALID),
out_shndx_(-1U),
symtab_index_(0),
dynsym_index_(0),
input_sections_(),
first_input_offset_(0),
fills_(),
postprocessing_buffer_(NULL),
needs_symtab_index_(false),
needs_dynsym_index_(false),
should_link_to_symtab_(false),
should_link_to_dynsym_(false),
after_input_sections_(false),
requires_postprocessing_(false),
found_in_sections_clause_(false),
has_load_address_(false),
info_uses_section_index_(false),
input_section_order_specified_(false),
may_sort_attached_input_sections_(false),
must_sort_attached_input_sections_(false),
attached_input_sections_are_sorted_(false),
is_relro_(false),
is_small_section_(false),
is_large_section_(false),
generate_code_fills_at_write_(false),
is_entsize_zero_(false),
section_offsets_need_adjustment_(false),
is_noload_(false),
always_keeps_input_sections_(false),
has_fixed_layout_(false),
is_patch_space_allowed_(false),
is_unique_segment_(false),
tls_offset_(0),
extra_segment_flags_(0),
segment_alignment_(0),
checkpoint_(NULL),
lookup_maps_(new Output_section_lookup_maps),
free_list_(),
free_space_fill_(NULL),
patch_space_(0)
{
// An unallocated section has no address. Forcing this means that
// we don't need special treatment for symbols defined in debug
// sections.
if ((flags & elfcpp::SHF_ALLOC) == 0)
this->set_address(0);
}
Output_section::~Output_section()
{
delete this->checkpoint_;
}
// Set the entry size.
void
Output_section::set_entsize(uint64_t v)
{
if (this->is_entsize_zero_)
;
else if (this->entsize_ == 0)
this->entsize_ = v;
else if (this->entsize_ != v)
{
this->entsize_ = 0;
this->is_entsize_zero_ = 1;
}
}
// Add the input section SHNDX, with header SHDR, named SECNAME, in
// OBJECT, to the Output_section. RELOC_SHNDX is the index of a
// relocation section which applies to this section, or 0 if none, or
// -1U if more than one. Return the offset of the input section
// within the output section. Return -1 if the input section will
// receive special handling. In the normal case we don't always keep
// track of input sections for an Output_section. Instead, each
// Object keeps track of the Output_section for each of its input
// sections. However, if HAVE_SECTIONS_SCRIPT is true, we do keep
// track of input sections here; this is used when SECTIONS appears in
// a linker script.
template<int size, bool big_endian>
off_t
Output_section::add_input_section(Layout* layout,
Sized_relobj_file<size, big_endian>* object,
unsigned int shndx,
const char* secname,
const elfcpp::Shdr<size, big_endian>& shdr,
unsigned int reloc_shndx,
bool have_sections_script)
{
elfcpp::Elf_Xword addralign = shdr.get_sh_addralign();
if ((addralign & (addralign - 1)) != 0)
{
object->error(_("invalid alignment %lu for section \"%s\""),
static_cast<unsigned long>(addralign), secname);
addralign = 1;
}
if (addralign > this->addralign_)
this->addralign_ = addralign;
typename elfcpp::Elf_types<size>::Elf_WXword sh_flags = shdr.get_sh_flags();
uint64_t entsize = shdr.get_sh_entsize();
// .debug_str is a mergeable string section, but is not always so
// marked by compilers. Mark manually here so we can optimize.
if (strcmp(secname, ".debug_str") == 0)
{
sh_flags |= (elfcpp::SHF_MERGE | elfcpp::SHF_STRINGS);
entsize = 1;
}
this->update_flags_for_input_section(sh_flags);
this->set_entsize(entsize);
// If this is a SHF_MERGE section, we pass all the input sections to
// a Output_data_merge. We don't try to handle relocations for such
// a section. We don't try to handle empty merge sections--they
// mess up the mappings, and are useless anyhow.
// FIXME: Need to handle merge sections during incremental update.
if ((sh_flags & elfcpp::SHF_MERGE) != 0
&& reloc_shndx == 0
&& shdr.get_sh_size() > 0
&& !parameters->incremental())
{
// Keep information about merged input sections for rebuilding fast
// lookup maps if we have sections-script or we do relaxation.
bool keeps_input_sections = (this->always_keeps_input_sections_
|| have_sections_script
|| parameters->target().may_relax());
if (this->add_merge_input_section(object, shndx, sh_flags, entsize,
addralign, keeps_input_sections))
{
// Tell the relocation routines that they need to call the
// output_offset method to determine the final address.
return -1;
}
}
section_size_type input_section_size = shdr.get_sh_size();
section_size_type uncompressed_size;
if (object->section_is_compressed(shndx, &uncompressed_size))
input_section_size = uncompressed_size;
off_t offset_in_section;
if (this->has_fixed_layout())
{
// For incremental updates, find a chunk of unused space in the section.
offset_in_section = this->free_list_.allocate(input_section_size,
addralign, 0);
if (offset_in_section == -1)
gold_fallback(_("out of patch space in section %s; "
"relink with --incremental-full"),
this->name());
return offset_in_section;
}
offset_in_section = this->current_data_size_for_child();
off_t aligned_offset_in_section = align_address(offset_in_section,
addralign);
this->set_current_data_size_for_child(aligned_offset_in_section
+ input_section_size);
// Determine if we want to delay code-fill generation until the output
// section is written. When the target is relaxing, we want to delay fill
// generating to avoid adjusting them during relaxation. Also, if we are
// sorting input sections we must delay fill generation.
if (!this->generate_code_fills_at_write_
&& !have_sections_script
&& (sh_flags & elfcpp::SHF_EXECINSTR) != 0
&& parameters->target().has_code_fill()
&& (parameters->target().may_relax()
|| layout->is_section_ordering_specified()))
{
gold_assert(this->fills_.empty());
this->generate_code_fills_at_write_ = true;
}
if (aligned_offset_in_section > offset_in_section
&& !this->generate_code_fills_at_write_
&& !have_sections_script
&& (sh_flags & elfcpp::SHF_EXECINSTR) != 0
&& parameters->target().has_code_fill())
{
// We need to add some fill data. Using fill_list_ when
// possible is an optimization, since we will often have fill
// sections without input sections.
off_t fill_len = aligned_offset_in_section - offset_in_section;
if (this->input_sections_.empty())
this->fills_.push_back(Fill(offset_in_section, fill_len));
else
{
std::string fill_data(parameters->target().code_fill(fill_len));
Output_data_const* odc = new Output_data_const(fill_data, 1);
this->input_sections_.push_back(Input_section(odc));
}
}
// We need to keep track of this section if we are already keeping
// track of sections, or if we are relaxing. Also, if this is a
// section which requires sorting, or which may require sorting in
// the future, we keep track of the sections. If the
// --section-ordering-file option is used to specify the order of
// sections, we need to keep track of sections.
if (this->always_keeps_input_sections_
|| have_sections_script
|| !this->input_sections_.empty()
|| this->may_sort_attached_input_sections()
|| this->must_sort_attached_input_sections()
|| parameters->options().user_set_Map()
|| parameters->target().may_relax()
|| layout->is_section_ordering_specified())
{
Input_section isecn(object, shndx, input_section_size, addralign);
/* If section ordering is requested by specifying a ordering file,
using --section-ordering-file, match the section name with
a pattern. */
if (parameters->options().section_ordering_file())
{
unsigned int section_order_index =
layout->find_section_order_index(std::string(secname));
if (section_order_index != 0)
{
isecn.set_section_order_index(section_order_index);
this->set_input_section_order_specified();
}
}
this->input_sections_.push_back(isecn);
}
return aligned_offset_in_section;
}
// Add arbitrary data to an output section.
void
Output_section::add_output_section_data(Output_section_data* posd)
{
Input_section inp(posd);
this->add_output_section_data(&inp);
if (posd->is_data_size_valid())
{
off_t offset_in_section;
if (this->has_fixed_layout())
{
// For incremental updates, find a chunk of unused space.
offset_in_section = this->free_list_.allocate(posd->data_size(),
posd->addralign(), 0);
if (offset_in_section == -1)
gold_fallback(_("out of patch space in section %s; "
"relink with --incremental-full"),
this->name());
// Finalize the address and offset now.
uint64_t addr = this->address();
off_t offset = this->offset();
posd->set_address_and_file_offset(addr + offset_in_section,
offset + offset_in_section);
}
else
{
offset_in_section = this->current_data_size_for_child();
off_t aligned_offset_in_section = align_address(offset_in_section,
posd->addralign());
this->set_current_data_size_for_child(aligned_offset_in_section
+ posd->data_size());
}
}
else if (this->has_fixed_layout())
{
// For incremental updates, arrange for the data to have a fixed layout.
// This will mean that additions to the data must be allocated from
// free space within the containing output section.
uint64_t addr = this->address();
posd->set_address(addr);
posd->set_file_offset(0);
// FIXME: This should eventually be unreachable.
// gold_unreachable();
}
}
// Add a relaxed input section.
void
Output_section::add_relaxed_input_section(Layout* layout,
Output_relaxed_input_section* poris,
const std::string& name)
{
Input_section inp(poris);
// If the --section-ordering-file option is used to specify the order of
// sections, we need to keep track of sections.
if (layout->is_section_ordering_specified())
{
unsigned int section_order_index =
layout->find_section_order_index(name);
if (section_order_index != 0)
{
inp.set_section_order_index(section_order_index);
this->set_input_section_order_specified();
}
}
this->add_output_section_data(&inp);
if (this->lookup_maps_->is_valid())
this->lookup_maps_->add_relaxed_input_section(poris->relobj(),
poris->shndx(), poris);
// For a relaxed section, we use the current data size. Linker scripts
// get all the input sections, including relaxed one from an output
// section and add them back to the same output section to compute the
// output section size. If we do not account for sizes of relaxed input
// sections, an output section would be incorrectly sized.
off_t offset_in_section = this->current_data_size_for_child();
off_t aligned_offset_in_section = align_address(offset_in_section,
poris->addralign());
this->set_current_data_size_for_child(aligned_offset_in_section
+ poris->current_data_size());
}
// Add arbitrary data to an output section by Input_section.
void
Output_section::add_output_section_data(Input_section* inp)
{
if (this->input_sections_.empty())
this->first_input_offset_ = this->current_data_size_for_child();
this->input_sections_.push_back(*inp);
uint64_t addralign = inp->addralign();
if (addralign > this->addralign_)
this->addralign_ = addralign;
inp->set_output_section(this);
}
// Add a merge section to an output section.
void
Output_section::add_output_merge_section(Output_section_data* posd,
bool is_string, uint64_t entsize)
{
Input_section inp(posd, is_string, entsize);
this->add_output_section_data(&inp);
}
// Add an input section to a SHF_MERGE section.
bool
Output_section::add_merge_input_section(Relobj* object, unsigned int shndx,
uint64_t flags, uint64_t entsize,
uint64_t addralign,
bool keeps_input_sections)
{
// We cannot merge sections with entsize == 0.
if (entsize == 0)
return false;
bool is_string = (flags & elfcpp::SHF_STRINGS) != 0;
// We cannot restore merged input section states.
gold_assert(this->checkpoint_ == NULL);
// Look up merge sections by required properties.
// Currently, we only invalidate the lookup maps in script processing
// and relaxation. We should not have done either when we reach here.
// So we assume that the lookup maps are valid to simply code.
gold_assert(this->lookup_maps_->is_valid());
Merge_section_properties msp(is_string, entsize, addralign);
Output_merge_base* pomb = this->lookup_maps_->find_merge_section(msp);
bool is_new = false;
if (pomb != NULL)
{
gold_assert(pomb->is_string() == is_string
&& pomb->entsize() == entsize
&& pomb->addralign() == addralign);
}
else
{
// Create a new Output_merge_data or Output_merge_string_data.
if (!is_string)
pomb = new Output_merge_data(entsize, addralign);