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Diffstat (limited to 'binutils-2.25/gold/output.cc')
| -rw-r--r-- | binutils-2.25/gold/output.cc | 5568 |
1 files changed, 5568 insertions, 0 deletions
diff --git a/binutils-2.25/gold/output.cc b/binutils-2.25/gold/output.cc new file mode 100644 index 00000000..348ad646 --- /dev/null +++ b/binutils-2.25/gold/output.cc @@ -0,0 +1,5568 @@ +// output.cc -- manage the output file for gold + +// Copyright 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013 +// 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(); +} + +// 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) +{ + 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); + + if (this->sort_relocs()) + { + gold_assert(dynamic); + std::sort(this->relocs_.begin(), this->relocs_.end(), + Sort_relocs_comparison()); + } + + unsigned char* pov = oview; + for (typename Relocs::const_iterator p = this->relocs_.begin(); + p != this->relocs_.end(); + ++p) + { + p->write(pov); + pov += reloc_size; + } + + gold_assert(pov - oview == oview_size); + + of->write_output_view(off, oview_size, oview); + + // We no longer need the relocation entries. + this->relocs_.clear(); +} + +// 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, 0); + 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; +} + +// 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 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 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; + + 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(); +} + +// 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; + } +} + +// Return whether this is the merge section for the input section +// SHNDX in OBJECT. + +inline bool +Output_section::Input_section::is_merge_section_for(const Relobj* object, + unsigned int shndx) const +{ + if (this->is_input_section()) + return false; + return this->u2_.posd->is_merge_section_for(object, shndx); +} + +// 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) +{ + 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); + else + { + switch (entsize) + { + case 1: + pomb = new Output_merge_string<char>(addralign); + break; + case 2: + pomb = new Output_merge_string<uint16_t>(addralign); + break; + case 4: + pomb = new Output_merge_string<uint32_t>(addralign); + break; + default: + return false; + } + } + // If we need to do script processing or relaxation, we need to keep + // the original input sections to rebuild the fast lookup maps. + if (keeps_input_sections) + pomb->set_keeps_input_sections(); + is_new = true; + } + + if (pomb->add_input_section(object, shndx)) + { + // Add new merge section to this output section and link merge + // section properties to new merge section in map. + if (is_new) + { + this->add_output_merge_section(pomb, is_string, entsize); + this->lookup_maps_->add_merge_section(msp, pomb); + } + + // Add input section to new merge section and link input section to new + // merge section in map. + this->lookup_maps_->add_merge_input_section(object, shndx, pomb); + return true; + } + else + { + // If add_input_section failed, delete new merge section to avoid + // exporting empty merge sections in Output_section::get_input_section. + if (is_new) + delete pomb; + return false; + } +} + +// Build a relaxation map to speed up relaxation of existing input sections. +// Look up to the first LIMIT elements in INPUT_SECTIONS. + +void +Output_section::build_relaxation_map( + const Input_section_list& input_sections, + size_t limit, + Relaxation_map* relaxation_map) const +{ + for (size_t i = 0; i < limit; ++i) + { + const Input_section& is(input_sections[i]); + if (is.is_input_section() || is.is_relaxed_input_section()) + { + Section_id sid(is.relobj(), is.shndx()); + (*relaxation_map)[sid] = i; + } + } +} + +// Convert regular input sections in INPUT_SECTIONS into relaxed input +// sections in RELAXED_SECTIONS. MAP is a prebuilt map from section id +// indices of INPUT_SECTIONS. + +void +Output_section::convert_input_sections_in_list_to_relaxed_sections( + const std::vector<Output_relaxed_input_section*>& relaxed_sections, + const Relaxation_map& map, + Input_section_list* input_sections) +{ + for (size_t i = 0; i < relaxed_sections.size(); ++i) + { + Output_relaxed_input_section* poris = relaxed_sections[i]; + Section_id sid(poris->relobj(), poris->shndx()); + Relaxation_map::const_iterator p = map.find(sid); + gold_assert(p != map.end()); + gold_assert((*input_sections)[p->second].is_input_section()); + + // Remember section order index of original input section + // if it is set. Copy it to the relaxed input section. + unsigned int soi = + (*input_sections)[p->second].section_order_index(); + (*input_sections)[p->second] = Input_section(poris); + (*input_sections)[p->second].set_section_order_index(soi); + } +} + +// Convert regular input sections into relaxed input sections. RELAXED_SECTIONS +// is a vector of pointers to Output_relaxed_input_section or its derived +// classes. The relaxed sections must correspond to existing input sections. + +void +Output_section::convert_input_sections_to_relaxed_sections( + const std::vector<Output_relaxed_input_section*>& relaxed_sections) +{ + gold_assert(parameters->target().may_relax()); + + // We want to make sure that restore_states does not undo the effect of + // this. If there is no checkpoint active, just search the current + // input section list and replace the sections there. If there is + // a checkpoint, also replace the sections there. + + // By default, we look at the whole list. + size_t limit = this->input_sections_.size(); + + if (this->checkpoint_ != NULL) + { + // Replace input sections with relaxed input section in the saved + // copy of the input section list. + if (this->checkpoint_->input_sections_saved()) + { + Relaxation_map map; + this->build_relaxation_map( + *(this->checkpoint_->input_sections()), + this->checkpoint_->input_sections()->size(), + &map); + this->convert_input_sections_in_list_to_relaxed_sections( + relaxed_sections, + map, + this->checkpoint_->input_sections()); + } + else + { + // We have not copied the input section list yet. Instead, just + // look at the portion that would be saved. + limit = this->checkpoint_->input_sections_size(); + } + } + + // Convert input sections in input_section_list. + Relaxation_map map; + this->build_relaxation_map(this->input_sections_, limit, &map); + this->convert_input_sections_in_list_to_relaxed_sections( + relaxed_sections, + map, + &this->input_sections_); + + // Update fast look-up map. + if (this->lookup_maps_->is_valid()) + for (size_t i = 0; i < relaxed_sections.size(); ++i) + { + Output_relaxed_input_section* poris = relaxed_sections[i]; + this->lookup_maps_->add_relaxed_input_section(poris->relobj(), + poris->shndx(), poris); + } +} + +// Update the output section flags based on input section flags. + +void +Output_section::update_flags_for_input_section(elfcpp::Elf_Xword flags) +{ + // If we created the section with SHF_ALLOC clear, we set the + // address. If we are now setting the SHF_ALLOC flag, we need to + // undo that. + if ((this->flags_ & elfcpp::SHF_ALLOC) == 0 + && (flags & elfcpp::SHF_ALLOC) != 0) + this->mark_address_invalid(); + + this->flags_ |= (flags + & (elfcpp::SHF_WRITE + | elfcpp::SHF_ALLOC + | elfcpp::SHF_EXECINSTR)); + + if ((flags & elfcpp::SHF_MERGE) == 0) + this->flags_ &=~ elfcpp::SHF_MERGE; + else + { + if (this->current_data_size_for_child() == 0) + this->flags_ |= elfcpp::SHF_MERGE; + } + + if ((flags & elfcpp::SHF_STRINGS) == 0) + this->flags_ &=~ elfcpp::SHF_STRINGS; + else + { + if (this->current_data_size_for_child() == 0) + this->flags_ |= elfcpp::SHF_STRINGS; + } +} + +// Find the merge section into which an input section with index SHNDX in +// OBJECT has been added. Return NULL if none found. + +Output_section_data* +Output_section::find_merge_section(const Relobj* object, + unsigned int shndx) const +{ + if (!this->lookup_maps_->is_valid()) + this->build_lookup_maps(); + return this->lookup_maps_->find_merge_section(object, shndx); +} + +// Build the lookup maps for merge and relaxed sections. This is needs +// to be declared as a const methods so that it is callable with a const +// Output_section pointer. The method only updates states of the maps. + +void +Output_section::build_lookup_maps() const +{ + this->lookup_maps_->clear(); + for (Input_section_list::const_iterator p = this->input_sections_.begin(); + p != this->input_sections_.end(); + ++p) + { + if (p->is_merge_section()) + { + Output_merge_base* pomb = p->output_merge_base(); + Merge_section_properties msp(pomb->is_string(), pomb->entsize(), + pomb->addralign()); + this->lookup_maps_->add_merge_section(msp, pomb); + for (Output_merge_base::Input_sections::const_iterator is = + pomb->input_sections_begin(); + is != pomb->input_sections_end(); + ++is) + { + const Const_section_id& csid = *is; + this->lookup_maps_->add_merge_input_section(csid.first, + csid.second, pomb); + } + + } + else if (p->is_relaxed_input_section()) + { + Output_relaxed_input_section* poris = p->relaxed_input_section(); + this->lookup_maps_->add_relaxed_input_section(poris->relobj(), + poris->shndx(), poris); + } + } +} + +// Find an relaxed input section corresponding to an input section +// in OBJECT with index SHNDX. + +const Output_relaxed_input_section* +Output_section::find_relaxed_input_section(const Relobj* object, + unsigned int shndx) const +{ + if (!this->lookup_maps_->is_valid()) + this->build_lookup_maps(); + return this->lookup_maps_->find_relaxed_input_section(object, shndx); +} + +// Given an address OFFSET relative to the start of input section +// SHNDX in OBJECT, return whether this address is being included in +// the final link. This should only be called if SHNDX in OBJECT has +// a special mapping. + +bool +Output_section::is_input_address_mapped(const Relobj* object, + unsigned int shndx, + off_t offset) const +{ + // Look at the Output_section_data_maps first. + const Output_section_data* posd = this->find_merge_section(object, shndx); + if (posd == NULL) + posd = this->find_relaxed_input_section(object, shndx); + + if (posd != NULL) + { + section_offset_type output_offset; + bool found = posd->output_offset(object, shndx, offset, &output_offset); + gold_assert(found); + return output_offset != -1; + } + + // Fall back to the slow look-up. + for (Input_section_list::const_iterator p = this->input_sections_.begin(); + p != this->input_sections_.end(); + ++p) + { + section_offset_type output_offset; + if (p->output_offset(object, shndx, offset, &output_offset)) + return output_offset != -1; + } + + // By default we assume that the address is mapped. This should + // only be called after we have passed all sections to Layout. At + // that point we should know what we are discarding. + return true; +} + +// Given an address OFFSET relative to the start of input section +// SHNDX in object OBJECT, return the output offset relative to the +// start of the input section in the output section. This should only +// be called if SHNDX in OBJECT has a special mapping. + +section_offset_type +Output_section::output_offset(const Relobj* object, unsigned int shndx, + section_offset_type offset) const +{ + // This can only be called meaningfully when we know the data size + // of this. + gold_assert(this->is_data_size_valid()); + + // Look at the Output_section_data_maps first. + const Output_section_data* posd = this->find_merge_section(object, shndx); + if (posd == NULL) + posd = this->find_relaxed_input_section(object, shndx); + if (posd != NULL) + { + section_offset_type output_offset; + bool found = posd->output_offset(object, shndx, offset, &output_offset); + gold_assert(found); + return output_offset; + } + + // Fall back to the slow look-up. + for (Input_section_list::const_iterator p = this->input_sections_.begin(); + p != this->input_sections_.end(); + ++p) + { + section_offset_type output_offset; + if (p->output_offset(object, shndx, offset, &output_offset)) + return output_offset; + } + gold_unreachable(); +} + +// Return the output virtual address of OFFSET relative to the start +// of input section SHNDX in object OBJECT. + +uint64_t +Output_section::output_address(const Relobj* object, unsigned int shndx, + off_t offset) const +{ + uint64_t addr = this->address() + this->first_input_offset_; + + // Look at the Output_section_data_maps first. + const Output_section_data* posd = this->find_merge_section(object, shndx); + if (posd == NULL) + posd = this->find_relaxed_input_section(object, shndx); + if (posd != NULL && posd->is_address_valid()) + { + section_offset_type output_offset; + bool found = posd->output_offset(object, shndx, offset, &output_offset); + gold_assert(found); + return posd->address() + output_offset; + } + + // Fall back to the slow look-up. + for (Input_section_list::const_iterator p = this->input_sections_.begin(); + p != this->input_sections_.end(); + ++p) + { + addr = align_address(addr, p->addralign()); + section_offset_type output_offset; + if (p->output_offset(object, shndx, offset, &output_offset)) + { + if (output_offset == -1) + return -1ULL; + return addr + output_offset; + } + addr += p->data_size(); + } + + // If we get here, it means that we don't know the mapping for this + // input section. This might happen in principle if + // add_input_section were called before add_output_section_data. + // But it should never actually happen. + + gold_unreachable(); +} + +// Find the output address of the start of the merged section for +// input section SHNDX in object OBJECT. + +bool +Output_section::find_starting_output_address(const Relobj* object, + unsigned int shndx, + uint64_t* paddr) const +{ + // FIXME: This becomes a bottle-neck if we have many relaxed sections. + // Looking up the merge section map does not always work as we sometimes + // find a merge section without its address set. + uint64_t addr = this->address() + this->first_input_offset_; + for (Input_section_list::const_iterator p = this->input_sections_.begin(); + p != this->input_sections_.end(); + ++p) + { + addr = align_address(addr, p->addralign()); + + // It would be nice if we could use the existing output_offset + // method to get the output offset of input offset 0. + // Unfortunately we don't know for sure that input offset 0 is + // mapped at all. + if (p->is_merge_section_for(object, shndx)) + { + *paddr = addr; + return true; + } + + addr += p->data_size(); + } + + // We couldn't find a merge output section for this input section. + return false; +} + +// Update the data size of an Output_section. + +void +Output_section::update_data_size() +{ + if (this->input_sections_.empty()) + return; + + if (this->must_sort_attached_input_sections() + || this->input_section_order_specified()) + this->sort_attached_input_sections(); + + off_t off = this->first_input_offset_; + for (Input_section_list::iterator p = this->input_sections_.begin(); + p != this->input_sections_.end(); + ++p) + { + off = align_address(off, p->addralign()); + off += p->current_data_size(); + } + + this->set_current_data_size_for_child(off); +} + +// Set the data size of an Output_section. This is where we handle +// setting the addresses of any Output_section_data objects. + +void +Output_section::set_final_data_size() +{ + off_t data_size; + + if (this->input_sections_.empty()) + data_size = this->current_data_size_for_child(); + else + { + if (this->must_sort_attached_input_sections() + || this->input_section_order_specified()) + this->sort_attached_input_sections(); + + uint64_t address = this->address(); + off_t startoff = this->offset(); + off_t off = startoff + this->first_input_offset_; + for (Input_section_list::iterator p = this->input_sections_.begin(); + p != this->input_sections_.end(); + ++p) + { + off = align_address(off, p->addralign()); + p->set_address_and_file_offset(address + (off - startoff), off, + startoff); + off += p->data_size(); + } + data_size = off - startoff; + } + + // For full incremental links, we want to allocate some patch space + // in most sections for subsequent incremental updates. + if (this->is_patch_space_allowed_ && parameters->incremental_full()) + { + double pct = parameters->options().incremental_patch(); + size_t extra = static_cast<size_t>(data_size * pct); + if (this->free_space_fill_ != NULL + && this->free_space_fill_->minimum_hole_size() > extra) + extra = this->free_space_fill_->minimum_hole_size(); + off_t new_size = align_address(data_size + extra, this->addralign()); + this->patch_space_ = new_size - data_size; + gold_debug(DEBUG_INCREMENTAL, + "set_final_data_size: %08lx + %08lx: section %s", + static_cast<long>(data_size), + static_cast<long>(this->patch_space_), + this->name()); + data_size = new_size; + } + + this->set_data_size(data_size); +} + +// Reset the address and file offset. + +void +Output_section::do_reset_address_and_file_offset() +{ + // An unallocated section has no address. Forcing this means that + // we don't need special treatment for symbols defined in debug + // sections. We do the same in the constructor. This does not + // apply to NOLOAD sections though. + if (((this->flags_ & elfcpp::SHF_ALLOC) == 0) && !this->is_noload_) + this->set_address(0); + + for (Input_section_list::iterator p = this->input_sections_.begin(); + p != this->input_sections_.end(); + ++p) + p->reset_address_and_file_offset(); + + // Remove any patch space that was added in set_final_data_size. + if (this->patch_space_ > 0) + { + this->set_current_data_size_for_child(this->current_data_size_for_child() + - this->patch_space_); + this->patch_space_ = 0; + } +} + +// Return true if address and file offset have the values after reset. + +bool +Output_section::do_address_and_file_offset_have_reset_values() const +{ + if (this->is_offset_valid()) + return false; + + // An unallocated section has address 0 after its construction or a reset. + if ((this->flags_ & elfcpp::SHF_ALLOC) == 0) + return this->is_address_valid() && this->address() == 0; + else + return !this->is_address_valid(); +} + +// Set the TLS offset. Called only for SHT_TLS sections. + +void +Output_section::do_set_tls_offset(uint64_t tls_base) +{ + this->tls_offset_ = this->address() - tls_base; +} + +// In a few cases we need to sort the input sections attached to an +// output section. This is used to implement the type of constructor +// priority ordering implemented by the GNU linker, in which the +// priority becomes part of the section name and the sections are +// sorted by name. We only do this for an output section if we see an +// attached input section matching ".ctors.*", ".dtors.*", +// ".init_array.*" or ".fini_array.*". + +class Output_section::Input_section_sort_entry +{ + public: + Input_section_sort_entry() + : input_section_(), index_(-1U), section_has_name_(false), + section_name_() + { } + + Input_section_sort_entry(const Input_section& input_section, + unsigned int index, + bool must_sort_attached_input_sections) + : input_section_(input_section), index_(index), + section_has_name_(input_section.is_input_section() + || input_section.is_relaxed_input_section()) + { + if (this->section_has_name_ + && must_sort_attached_input_sections) + { + // This is only called single-threaded from Layout::finalize, + // so it is OK to lock. Unfortunately we have no way to pass + // in a Task token. + const Task* dummy_task = reinterpret_cast<const Task*>(-1); + Object* obj = (input_section.is_input_section() + ? input_section.relobj() + : input_section.relaxed_input_section()->relobj()); + Task_lock_obj<Object> tl(dummy_task, obj); + + // This is a slow operation, which should be cached in + // Layout::layout if this becomes a speed problem. + this->section_name_ = obj->section_name(input_section.shndx()); + } + } + + // Return the Input_section. + const Input_section& + input_section() const + { + gold_assert(this->index_ != -1U); + return this->input_section_; + } + + // The index of this entry in the original list. This is used to + // make the sort stable. + unsigned int + index() const + { + gold_assert(this->index_ != -1U); + return this->index_; + } + + // Whether there is a section name. + bool + section_has_name() const + { return this->section_has_name_; } + + // The section name. + const std::string& + section_name() const + { + gold_assert(this->section_has_name_); + return this->section_name_; + } + + // Return true if the section name has a priority. This is assumed + // to be true if it has a dot after the initial dot. + bool + has_priority() const + { + gold_assert(this->section_has_name_); + return this->section_name_.find('.', 1) != std::string::npos; + } + + // Return the priority. Believe it or not, gcc encodes the priority + // differently for .ctors/.dtors and .init_array/.fini_array + // sections. + unsigned int + get_priority() const + { + gold_assert(this->section_has_name_); + bool is_ctors; + if (is_prefix_of(".ctors.", this->section_name_.c_str()) + || is_prefix_of(".dtors.", this->section_name_.c_str())) + is_ctors = true; + else if (is_prefix_of(".init_array.", this->section_name_.c_str()) + || is_prefix_of(".fini_array.", this->section_name_.c_str())) + is_ctors = false; + else + return 0; + char* end; + unsigned long prio = strtoul((this->section_name_.c_str() + + (is_ctors ? 7 : 12)), + &end, 10); + if (*end != '\0') + return 0; + else if (is_ctors) + return 65535 - prio; + else + return prio; + } + + // Return true if this an input file whose base name matches + // FILE_NAME. The base name must have an extension of ".o", and + // must be exactly FILE_NAME.o or FILE_NAME, one character, ".o". + // This is to match crtbegin.o as well as crtbeginS.o without + // getting confused by other possibilities. Overall matching the + // file name this way is a dreadful hack, but the GNU linker does it + // in order to better support gcc, and we need to be compatible. + bool + match_file_name(const char* file_name) const + { + if (this->input_section_.is_output_section_data()) + return false; + return Layout::match_file_name(this->input_section_.relobj(), file_name); + } + + // Returns 1 if THIS should appear before S in section order, -1 if S + // appears before THIS and 0 if they are not comparable. + int + compare_section_ordering(const Input_section_sort_entry& s) const + { + unsigned int this_secn_index = this->input_section_.section_order_index(); + unsigned int s_secn_index = s.input_section().section_order_index(); + if (this_secn_index > 0 && s_secn_index > 0) + { + if (this_secn_index < s_secn_index) + return 1; + else if (this_secn_index > s_secn_index) + return -1; + } + return 0; + } + + private: + // The Input_section we are sorting. + Input_section input_section_; + // The index of this Input_section in the original list. + unsigned int index_; + // Whether this Input_section has a section name--it won't if this + // is some random Output_section_data. + bool section_has_name_; + // The section name if there is one. + std::string section_name_; +}; + +// Return true if S1 should come before S2 in the output section. + +bool +Output_section::Input_section_sort_compare::operator()( + const Output_section::Input_section_sort_entry& s1, + const Output_section::Input_section_sort_entry& s2) const +{ + // crtbegin.o must come first. + bool s1_begin = s1.match_file_name("crtbegin"); + bool s2_begin = s2.match_file_name("crtbegin"); + if (s1_begin || s2_begin) + { + if (!s1_begin) + return false; + if (!s2_begin) + return true; + return s1.index() < s2.index(); + } + + // crtend.o must come last. + bool s1_end = s1.match_file_name("crtend"); + bool s2_end = s2.match_file_name("crtend"); + if (s1_end || s2_end) + { + if (!s1_end) + return true; + if (!s2_end) + return false; + return s1.index() < s2.index(); + } + + // We sort all the sections with no names to the end. + if (!s1.section_has_name() || !s2.section_has_name()) + { + if (s1.section_has_name()) + return true; + if (s2.section_has_name()) + return false; + return s1.index() < s2.index(); + } + + // A section with a priority follows a section without a priority. + bool s1_has_priority = s1.has_priority(); + bool s2_has_priority = s2.has_priority(); + if (s1_has_priority && !s2_has_priority) + return false; + if (!s1_has_priority && s2_has_priority) + return true; + + // Check if a section order exists for these sections through a section + // ordering file. If sequence_num is 0, an order does not exist. + int sequence_num = s1.compare_section_ordering(s2); + if (sequence_num != 0) + return sequence_num == 1; + + // Otherwise we sort by name. + int compare = s1.section_name().compare(s2.section_name()); + if (compare != 0) + return compare < 0; + + // Otherwise we keep the input order. + return s1.index() < s2.index(); +} + +// Return true if S1 should come before S2 in an .init_array or .fini_array +// output section. + +bool +Output_section::Input_section_sort_init_fini_compare::operator()( + const Output_section::Input_section_sort_entry& s1, + const Output_section::Input_section_sort_entry& s2) const +{ + // We sort all the sections with no names to the end. + if (!s1.section_has_name() || !s2.section_has_name()) + { + if (s1.section_has_name()) + return true; + if (s2.section_has_name()) + return false; + return s1.index() < s2.index(); + } + + // A section without a priority follows a section with a priority. + // This is the reverse of .ctors and .dtors sections. + bool s1_has_priority = s1.has_priority(); + bool s2_has_priority = s2.has_priority(); + if (s1_has_priority && !s2_has_priority) + return true; + if (!s1_has_priority && s2_has_priority) + return false; + + // .ctors and .dtors sections without priority come after + // .init_array and .fini_array sections without priority. + if (!s1_has_priority + && (s1.section_name() == ".ctors" || s1.section_name() == ".dtors") + && s1.section_name() != s2.section_name()) + return false; + if (!s2_has_priority + && (s2.section_name() == ".ctors" || s2.section_name() == ".dtors") + && s2.section_name() != s1.section_name()) + return true; + + // Sort by priority if we can. + if (s1_has_priority) + { + unsigned int s1_prio = s1.get_priority(); + unsigned int s2_prio = s2.get_priority(); + if (s1_prio < s2_prio) + return true; + else if (s1_prio > s2_prio) + return false; + } + + // Check if a section order exists for these sections through a section + // ordering file. If sequence_num is 0, an order does not exist. + int sequence_num = s1.compare_section_ordering(s2); + if (sequence_num != 0) + return sequence_num == 1; + + // Otherwise we sort by name. + int compare = s1.section_name().compare(s2.section_name()); + if (compare != 0) + return compare < 0; + + // Otherwise we keep the input order. + return s1.index() < s2.index(); +} + +// Return true if S1 should come before S2. Sections that do not match +// any pattern in the section ordering file are placed ahead of the sections +// that match some pattern. + +bool +Output_section::Input_section_sort_section_order_index_compare::operator()( + const Output_section::Input_section_sort_entry& s1, + const Output_section::Input_section_sort_entry& s2) const +{ + unsigned int s1_secn_index = s1.input_section().section_order_index(); + unsigned int s2_secn_index = s2.input_section().section_order_index(); + + // Keep input order if section ordering cannot determine order. + if (s1_secn_index == s2_secn_index) + return s1.index() < s2.index(); + + return s1_secn_index < s2_secn_index; +} + +// Return true if S1 should come before S2. This is the sort comparison +// function for .text to sort sections with prefixes +// .text.{unlikely,exit,startup,hot} before other sections. + +bool +Output_section::Input_section_sort_section_prefix_special_ordering_compare + ::operator()( + const Output_section::Input_section_sort_entry& s1, + const Output_section::Input_section_sort_entry& s2) const +{ + // We sort all the sections with no names to the end. + if (!s1.section_has_name() || !s2.section_has_name()) + { + if (s1.section_has_name()) + return true; + if (s2.section_has_name()) + return false; + return s1.index() < s2.index(); + } + + // Some input section names have special ordering requirements. + int o1 = Layout::special_ordering_of_input_section(s1.section_name().c_str()); + int o2 = Layout::special_ordering_of_input_section(s2.section_name().c_str()); + if (o1 != o2) + { + if (o1 < 0) + return false; + else if (o2 < 0) + return true; + else + return o1 < o2; + } + + // Keep input order otherwise. + return s1.index() < s2.index(); +} + +// Return true if S1 should come before S2. This is the sort comparison +// function for sections to sort them by name. + +bool +Output_section::Input_section_sort_section_name_compare + ::operator()( + const Output_section::Input_section_sort_entry& s1, + const Output_section::Input_section_sort_entry& s2) const +{ + // We sort all the sections with no names to the end. + if (!s1.section_has_name() || !s2.section_has_name()) + { + if (s1.section_has_name()) + return true; + if (s2.section_has_name()) + return false; + return s1.index() < s2.index(); + } + + // We sort by name. + int compare = s1.section_name().compare(s2.section_name()); + if (compare != 0) + return compare < 0; + + // Keep input order otherwise. + return s1.index() < s2.index(); +} + +// This updates the section order index of input sections according to the +// the order specified in the mapping from Section id to order index. + +void +Output_section::update_section_layout( + const Section_layout_order* order_map) +{ + for (Input_section_list::iterator p = this->input_sections_.begin(); + p != this->input_sections_.end(); + ++p) + { + if (p->is_input_section() + || p->is_relaxed_input_section()) + { + Object* obj = (p->is_input_section() + ? p->relobj() + : p->relaxed_input_section()->relobj()); + unsigned int shndx = p->shndx(); + Section_layout_order::const_iterator it + = order_map->find(Section_id(obj, shndx)); + if (it == order_map->end()) + continue; + unsigned int section_order_index = it->second; + if (section_order_index != 0) + { + p->set_section_order_index(section_order_index); + this->set_input_section_order_specified(); + } + } + } +} + +// Sort the input sections attached to an output section. + +void +Output_section::sort_attached_input_sections() +{ + if (this->attached_input_sections_are_sorted_) + return; + + if (this->checkpoint_ != NULL + && !this->checkpoint_->input_sections_saved()) + this->checkpoint_->save_input_sections(); + + // The only thing we know about an input section is the object and + // the section index. We need the section name. Recomputing this + // is slow but this is an unusual case. If this becomes a speed + // problem we can cache the names as required in Layout::layout. + + // We start by building a larger vector holding a copy of each + // Input_section, plus its current index in the list and its name. + std::vector<Input_section_sort_entry> sort_list; + + unsigned int i = 0; + for (Input_section_list::iterator p = this->input_sections_.begin(); + p != this->input_sections_.end(); + ++p, ++i) + sort_list.push_back(Input_section_sort_entry(*p, i, + this->must_sort_attached_input_sections())); + + // Sort the input sections. + if (this->must_sort_attached_input_sections()) + { + if (this->type() == elfcpp::SHT_PREINIT_ARRAY + || this->type() == elfcpp::SHT_INIT_ARRAY + || this->type() == elfcpp::SHT_FINI_ARRAY) + std::sort(sort_list.begin(), sort_list.end(), + Input_section_sort_init_fini_compare()); + else if (strcmp(parameters->options().sort_section(), "name") == 0) + std::sort(sort_list.begin(), sort_list.end(), + Input_section_sort_section_name_compare()); + else if (strcmp(this->name(), ".text") == 0) + std::sort(sort_list.begin(), sort_list.end(), + Input_section_sort_section_prefix_special_ordering_compare()); + else + std::sort(sort_list.begin(), sort_list.end(), + Input_section_sort_compare()); + } + else + { + gold_assert(this->input_section_order_specified()); + std::sort(sort_list.begin(), sort_list.end(), + Input_section_sort_section_order_index_compare()); + } + + // Copy the sorted input sections back to our list. + this->input_sections_.clear(); + for (std::vector<Input_section_sort_entry>::iterator p = sort_list.begin(); + p != sort_list.end(); + ++p) + this->input_sections_.push_back(p->input_section()); + sort_list.clear(); + + // Remember that we sorted the input sections, since we might get + // called again. + this->attached_input_sections_are_sorted_ = true; +} + +// Write the section header to *OSHDR. + +template<int size, bool big_endian> +void +Output_section::write_header(const Layout* layout, + const Stringpool* secnamepool, + elfcpp::Shdr_write<size, big_endian>* oshdr) const +{ + oshdr->put_sh_name(secnamepool->get_offset(this->name_)); + oshdr->put_sh_type(this->type_); + + elfcpp::Elf_Xword flags = this->flags_; + if (this->info_section_ != NULL && this->info_uses_section_index_) + flags |= elfcpp::SHF_INFO_LINK; + oshdr->put_sh_flags(flags); + + oshdr->put_sh_addr(this->address()); + oshdr->put_sh_offset(this->offset()); + oshdr->put_sh_size(this->data_size()); + if (this->link_section_ != NULL) + oshdr->put_sh_link(this->link_section_->out_shndx()); + else if (this->should_link_to_symtab_) + oshdr->put_sh_link(layout->symtab_section_shndx()); + else if (this->should_link_to_dynsym_) + oshdr->put_sh_link(layout->dynsym_section()->out_shndx()); + else + oshdr->put_sh_link(this->link_); + + elfcpp::Elf_Word info; + if (this->info_section_ != NULL) + { + if (this->info_uses_section_index_) + info = this->info_section_->out_shndx(); + else + info = this->info_section_->symtab_index(); + } + else if (this->info_symndx_ != NULL) + info = this->info_symndx_->symtab_index(); + else + info = this->info_; + oshdr->put_sh_info(info); + + oshdr->put_sh_addralign(this->addralign_); + oshdr->put_sh_entsize(this->entsize_); +} + +// Write out the data. For input sections the data is written out by +// Object::relocate, but we have to handle Output_section_data objects +// here. + +void +Output_section::do_write(Output_file* of) +{ + gold_assert(!this->requires_postprocessing()); + + // If the target performs relaxation, we delay filler generation until now. + gold_assert(!this->generate_code_fills_at_write_ || this->fills_.empty()); + + off_t output_section_file_offset = this->offset(); + for (Fill_list::iterator p = this->fills_.begin(); + p != this->fills_.end(); + ++p) + { + std::string fill_data(parameters->target().code_fill(p->length())); + of->write(output_section_file_offset + p->section_offset(), + fill_data.data(), fill_data.size()); + } + + off_t off = this->offset() + this->first_input_offset_; + for (Input_section_list::iterator p = this->input_sections_.begin(); + p != this->input_sections_.end(); + ++p) + { + off_t aligned_off = align_address(off, p->addralign()); + if (this->generate_code_fills_at_write_ && (off != aligned_off)) + { + size_t fill_len = aligned_off - off; + std::string fill_data(parameters->target().code_fill(fill_len)); + of->write(off, fill_data.data(), fill_data.size()); + } + + p->write(of); + off = aligned_off + p->data_size(); + } + + // For incremental links, fill in unused chunks in debug sections + // with dummy compilation unit headers. + if (this->free_space_fill_ != NULL) + { + for (Free_list::Const_iterator p = this->free_list_.begin(); + p != this->free_list_.end(); + ++p) + { + off_t off = p->start_; + size_t len = p->end_ - off; + this->free_space_fill_->write(of, this->offset() + off, len); + } + if (this->patch_space_ > 0) + { + off_t off = this->current_data_size_for_child() - this->patch_space_; + this->free_space_fill_->write(of, this->offset() + off, + this->patch_space_); + } + } +} + +// If a section requires postprocessing, create the buffer to use. + +void +Output_section::create_postprocessing_buffer() +{ + gold_assert(this->requires_postprocessing()); + + if (this->postprocessing_buffer_ != NULL) + return; + + if (!this->input_sections_.empty()) + { + off_t off = this->first_input_offset_; + for (Input_section_list::iterator p = this->input_sections_.begin(); + p != this->input_sections_.end(); + ++p) + { + off = align_address(off, p->addralign()); + p->finalize_data_size(); + off += p->data_size(); + } + this->set_current_data_size_for_child(off); + } + + off_t buffer_size = this->current_data_size_for_child(); + this->postprocessing_buffer_ = new unsigned char[buffer_size]; +} + +// Write all the data of an Output_section into the postprocessing +// buffer. This is used for sections which require postprocessing, +// such as compression. Input sections are handled by +// Object::Relocate. + +void +Output_section::write_to_postprocessing_buffer() +{ + gold_assert(this->requires_postprocessing()); + + // If the target performs relaxation, we delay filler generation until now. + gold_assert(!this->generate_code_fills_at_write_ || this->fills_.empty()); + + unsigned char* buffer = this->postprocessing_buffer(); + for (Fill_list::iterator p = this->fills_.begin(); + p != this->fills_.end(); + ++p) + { + std::string fill_data(parameters->target().code_fill(p->length())); + memcpy(buffer + p->section_offset(), fill_data.data(), + fill_data.size()); + } + + off_t off = this->first_input_offset_; + for (Input_section_list::iterator p = this->input_sections_.begin(); + p != this->input_sections_.end(); + ++p) + { + off_t aligned_off = align_address(off, p->addralign()); + if (this->generate_code_fills_at_write_ && (off != aligned_off)) + { + size_t fill_len = aligned_off - off; + std::string fill_data(parameters->target().code_fill(fill_len)); + memcpy(buffer + off, fill_data.data(), fill_data.size()); + } + + p->write_to_buffer(buffer + aligned_off); + off = aligned_off + p->data_size(); + } +} + +// Get the input sections for linker script processing. We leave +// behind the Output_section_data entries. Note that this may be +// slightly incorrect for merge sections. We will leave them behind, +// but it is possible that the script says that they should follow +// some other input sections, as in: +// .rodata { *(.rodata) *(.rodata.cst*) } +// For that matter, we don't handle this correctly: +// .rodata { foo.o(.rodata.cst*) *(.rodata.cst*) } +// With luck this will never matter. + +uint64_t +Output_section::get_input_sections( + uint64_t address, + const std::string& fill, + std::list<Input_section>* input_sections) +{ + if (this->checkpoint_ != NULL + && !this->checkpoint_->input_sections_saved()) + this->checkpoint_->save_input_sections(); + + // Invalidate fast look-up maps. + this->lookup_maps_->invalidate(); + + uint64_t orig_address = address; + + address = align_address(address, this->addralign()); + + Input_section_list remaining; + for (Input_section_list::iterator p = this->input_sections_.begin(); + p != this->input_sections_.end(); + ++p) + { + if (p->is_input_section() + || p->is_relaxed_input_section() + || p->is_merge_section()) + input_sections->push_back(*p); + else + { + uint64_t aligned_address = align_address(address, p->addralign()); + if (aligned_address != address && !fill.empty()) + { + section_size_type length = + convert_to_section_size_type(aligned_address - address); + std::string this_fill; + this_fill.reserve(length); + while (this_fill.length() + fill.length() <= length) + this_fill += fill; + if (this_fill.length() < length) + this_fill.append(fill, 0, length - this_fill.length()); + + Output_section_data* posd = new Output_data_const(this_fill, 0); + remaining.push_back(Input_section(posd)); + } + address = aligned_address; + + remaining.push_back(*p); + + p->finalize_data_size(); + address += p->data_size(); + } + } + + this->input_sections_.swap(remaining); + this->first_input_offset_ = 0; + + uint64_t data_size = address - orig_address; + this->set_current_data_size_for_child(data_size); + return data_size; +} + +// Add a script input section. SIS is an Output_section::Input_section, +// which can be either a plain input section or a special input section like +// a relaxed input section. For a special input section, its size must be +// finalized. + +void +Output_section::add_script_input_section(const Input_section& sis) +{ + uint64_t data_size = sis.data_size(); + uint64_t addralign = sis.addralign(); + if (addralign > this->addralign_) + this->addralign_ = addralign; + + off_t 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 + + data_size); + + this->input_sections_.push_back(sis); + + // Update fast lookup maps if necessary. + if (this->lookup_maps_->is_valid()) + { + if (sis.is_merge_section()) + { + Output_merge_base* pomb = sis.output_merge_base(); + Merge_section_properties msp(pomb->is_string(), pomb->entsize(), + pomb->addralign()); + this->lookup_maps_->add_merge_section(msp, pomb); + for (Output_merge_base::Input_sections::const_iterator p = + pomb->input_sections_begin(); + p != pomb->input_sections_end(); + ++p) + this->lookup_maps_->add_merge_input_section(p->first, p->second, + pomb); + } + else if (sis.is_relaxed_input_section()) + { + Output_relaxed_input_section* poris = sis.relaxed_input_section(); + this->lookup_maps_->add_relaxed_input_section(poris->relobj(), + poris->shndx(), poris); + } + } +} + +// Save states for relaxation. + +void +Output_section::save_states() +{ + gold_assert(this->checkpoint_ == NULL); + Checkpoint_output_section* checkpoint = + new Checkpoint_output_section(this->addralign_, this->flags_, + this->input_sections_, + this->first_input_offset_, + this->attached_input_sections_are_sorted_); + this->checkpoint_ = checkpoint; + gold_assert(this->fills_.empty()); +} + +void +Output_section::discard_states() +{ + gold_assert(this->checkpoint_ != NULL); + delete this->checkpoint_; + this->checkpoint_ = NULL; + gold_assert(this->fills_.empty()); + + // Simply invalidate the fast lookup maps since we do not keep + // track of them. + this->lookup_maps_->invalidate(); +} + +void +Output_section::restore_states() +{ + gold_assert(this->checkpoint_ != NULL); + Checkpoint_output_section* checkpoint = this->checkpoint_; + + this->addralign_ = checkpoint->addralign(); + this->flags_ = checkpoint->flags(); + this->first_input_offset_ = checkpoint->first_input_offset(); + + if (!checkpoint->input_sections_saved()) + { + // If we have not copied the input sections, just resize it. + size_t old_size = checkpoint->input_sections_size(); + gold_assert(this->input_sections_.size() >= old_size); + this->input_sections_.resize(old_size); + } + else + { + // We need to copy the whole list. This is not efficient for + // extremely large output with hundreads of thousands of input + // objects. We may need to re-think how we should pass sections + // to scripts. + this->input_sections_ = *checkpoint->input_sections(); + } + + this->attached_input_sections_are_sorted_ = + checkpoint->attached_input_sections_are_sorted(); + + // Simply invalidate the fast lookup maps since we do not keep + // track of them. + this->lookup_maps_->invalidate(); +} + +// Update the section offsets of input sections in this. This is required if +// relaxation causes some input sections to change sizes. + +void +Output_section::adjust_section_offsets() +{ + if (!this->section_offsets_need_adjustment_) + return; + + off_t off = 0; + for (Input_section_list::iterator p = this->input_sections_.begin(); + p != this->input_sections_.end(); + ++p) + { + off = align_address(off, p->addralign()); + if (p->is_input_section()) + p->relobj()->set_section_offset(p->shndx(), off); + off += p->data_size(); + } + + this->section_offsets_need_adjustment_ = false; +} + +// Print to the map file. + +void +Output_section::do_print_to_mapfile(Mapfile* mapfile) const +{ + mapfile->print_output_section(this); + + for (Input_section_list::const_iterator p = this->input_sections_.begin(); + p != this->input_sections_.end(); + ++p) + p->print_to_mapfile(mapfile); +} + +// Print stats for merge sections to stderr. + +void +Output_section::print_merge_stats() +{ + Input_section_list::iterator p; + for (p = this->input_sections_.begin(); + p != this->input_sections_.end(); + ++p) + p->print_merge_stats(this->name_); +} + +// Set a fixed layout for the section. Used for incremental update links. + +void +Output_section::set_fixed_layout(uint64_t sh_addr, off_t sh_offset, + off_t sh_size, uint64_t sh_addralign) +{ + this->addralign_ = sh_addralign; + this->set_current_data_size(sh_size); + if ((this->flags_ & elfcpp::SHF_ALLOC) != 0) + this->set_address(sh_addr); + this->set_file_offset(sh_offset); + this->finalize_data_size(); + this->free_list_.init(sh_size, false); + this->has_fixed_layout_ = true; +} + +// Reserve space within the fixed layout for the section. Used for +// incremental update links. + +void +Output_section::reserve(uint64_t sh_offset, uint64_t sh_size) +{ + this->free_list_.remove(sh_offset, sh_offset + sh_size); +} + +// Allocate space from the free list for the section. Used for +// incremental update links. + +off_t +Output_section::allocate(off_t len, uint64_t addralign) +{ + return this->free_list_.allocate(len, addralign, 0); +} + +// Output segment methods. + +Output_segment::Output_segment(elfcpp::Elf_Word type, elfcpp::Elf_Word flags) + : vaddr_(0), + paddr_(0), + memsz_(0), + max_align_(0), + min_p_align_(0), + offset_(0), + filesz_(0), + type_(type), + flags_(flags), + is_max_align_known_(false), + are_addresses_set_(false), + is_large_data_segment_(false), + is_unique_segment_(false) +{ + // The ELF ABI specifies that a PT_TLS segment always has PF_R as + // the flags. + if (type == elfcpp::PT_TLS) + this->flags_ = elfcpp::PF_R; +} + +// Add an Output_section to a PT_LOAD Output_segment. + +void +Output_segment::add_output_section_to_load(Layout* layout, + Output_section* os, + elfcpp::Elf_Word seg_flags) +{ + gold_assert(this->type() == elfcpp::PT_LOAD); + gold_assert((os->flags() & elfcpp::SHF_ALLOC) != 0); + gold_assert(!this->is_max_align_known_); + gold_assert(os->is_large_data_section() == this->is_large_data_segment()); + + this->update_flags_for_output_section(seg_flags); + + // We don't want to change the ordering if we have a linker script + // with a SECTIONS clause. + Output_section_order order = os->order(); + if (layout->script_options()->saw_sections_clause()) + order = static_cast<Output_section_order>(0); + else + gold_assert(order != ORDER_INVALID); + + this->output_lists_[order].push_back(os); +} + +// Add an Output_section to a non-PT_LOAD Output_segment. + +void +Output_segment::add_output_section_to_nonload(Output_section* os, + elfcpp::Elf_Word seg_flags) +{ + gold_assert(this->type() != elfcpp::PT_LOAD); + gold_assert((os->flags() & elfcpp::SHF_ALLOC) != 0); + gold_assert(!this->is_max_align_known_); + + this->update_flags_for_output_section(seg_flags); + + this->output_lists_[0].push_back(os); +} + +// Remove an Output_section from this segment. It is an error if it +// is not present. + +void +Output_segment::remove_output_section(Output_section* os) +{ + for (int i = 0; i < static_cast<int>(ORDER_MAX); ++i) + { + Output_data_list* pdl = &this->output_lists_[i]; + for (Output_data_list::iterator p = pdl->begin(); p != pdl->end(); ++p) + { + if (*p == os) + { + pdl->erase(p); + return; + } + } + } + gold_unreachable(); +} + +// Add an Output_data (which need not be an Output_section) to the +// start of a segment. + +void +Output_segment::add_initial_output_data(Output_data* od) +{ + gold_assert(!this->is_max_align_known_); + Output_data_list::iterator p = this->output_lists_[0].begin(); + this->output_lists_[0].insert(p, od); +} + +// Return true if this segment has any sections which hold actual +// data, rather than being a BSS section. + +bool +Output_segment::has_any_data_sections() const +{ + for (int i = 0; i < static_cast<int>(ORDER_MAX); ++i) + { + const Output_data_list* pdl = &this->output_lists_[i]; + for (Output_data_list::const_iterator p = pdl->begin(); + p != pdl->end(); + ++p) + { + if (!(*p)->is_section()) + return true; + if ((*p)->output_section()->type() != elfcpp::SHT_NOBITS) + return true; + } + } + return false; +} + +// Return whether the first data section (not counting TLS sections) +// is a relro section. + +bool +Output_segment::is_first_section_relro() const +{ + for (int i = 0; i < static_cast<int>(ORDER_MAX); ++i) + { + if (i == static_cast<int>(ORDER_TLS_DATA) + || i == static_cast<int>(ORDER_TLS_BSS)) + continue; + const Output_data_list* pdl = &this->output_lists_[i]; + if (!pdl->empty()) + { + Output_data* p = pdl->front(); + return p->is_section() && p->output_section()->is_relro(); + } + } + return false; +} + +// Return the maximum alignment of the Output_data in Output_segment. + +uint64_t +Output_segment::maximum_alignment() +{ + if (!this->is_max_align_known_) + { + for (int i = 0; i < static_cast<int>(ORDER_MAX); ++i) + { + const Output_data_list* pdl = &this->output_lists_[i]; + uint64_t addralign = Output_segment::maximum_alignment_list(pdl); + if (addralign > this->max_align_) + this->max_align_ = addralign; + } + this->is_max_align_known_ = true; + } + + return this->max_align_; +} + +// Return the maximum alignment of a list of Output_data. + +uint64_t +Output_segment::maximum_alignment_list(const Output_data_list* pdl) +{ + uint64_t ret = 0; + for (Output_data_list::const_iterator p = pdl->begin(); + p != pdl->end(); + ++p) + { + uint64_t addralign = (*p)->addralign(); + if (addralign > ret) + ret = addralign; + } + return ret; +} + +// Return whether this segment has any dynamic relocs. + +bool +Output_segment::has_dynamic_reloc() const +{ + for (int i = 0; i < static_cast<int>(ORDER_MAX); ++i) + if (this->has_dynamic_reloc_list(&this->output_lists_[i])) + return true; + return false; +} + +// Return whether this Output_data_list has any dynamic relocs. + +bool +Output_segment::has_dynamic_reloc_list(const Output_data_list* pdl) const +{ + for (Output_data_list::const_iterator p = pdl->begin(); + p != pdl->end(); + ++p) + if ((*p)->has_dynamic_reloc()) + return true; + return false; +} + +// Set the section addresses for an Output_segment. If RESET is true, +// reset the addresses first. ADDR is the address and *POFF is the +// file offset. Set the section indexes starting with *PSHNDX. +// INCREASE_RELRO is the size of the portion of the first non-relro +// section that should be included in the PT_GNU_RELRO segment. +// If this segment has relro sections, and has been aligned for +// that purpose, set *HAS_RELRO to TRUE. Return the address of +// the immediately following segment. Update *HAS_RELRO, *POFF, +// and *PSHNDX. + +uint64_t +Output_segment::set_section_addresses(const Target* target, + Layout* layout, bool reset, + uint64_t addr, + unsigned int* increase_relro, + bool* has_relro, + off_t* poff, + unsigned int* pshndx) +{ + gold_assert(this->type_ == elfcpp::PT_LOAD); + + uint64_t last_relro_pad = 0; + off_t orig_off = *poff; + + bool in_tls = false; + + // If we have relro sections, we need to pad forward now so that the + // relro sections plus INCREASE_RELRO end on an abi page boundary. + if (parameters->options().relro() + && this->is_first_section_relro() + && (!this->are_addresses_set_ || reset)) + { + uint64_t relro_size = 0; + off_t off = *poff; + uint64_t max_align = 0; + for (int i = 0; i <= static_cast<int>(ORDER_RELRO_LAST); ++i) + { + Output_data_list* pdl = &this->output_lists_[i]; + Output_data_list::iterator p; + for (p = pdl->begin(); p != pdl->end(); ++p) + { + if (!(*p)->is_section()) + break; + uint64_t align = (*p)->addralign(); + if (align > max_align) + max_align = align; + if ((*p)->is_section_flag_set(elfcpp::SHF_TLS)) + in_tls = true; + else if (in_tls) + { + // Align the first non-TLS section to the alignment + // of the TLS segment. + align = max_align; + in_tls = false; + } + relro_size = align_address(relro_size, align); + // Ignore the size of the .tbss section. + if ((*p)->is_section_flag_set(elfcpp::SHF_TLS) + && (*p)->is_section_type(elfcpp::SHT_NOBITS)) + continue; + if ((*p)->is_address_valid()) + relro_size += (*p)->data_size(); + else + { + // FIXME: This could be faster. + (*p)->set_address_and_file_offset(addr + relro_size, + off + relro_size); + relro_size += (*p)->data_size(); + (*p)->reset_address_and_file_offset(); + } + } + if (p != pdl->end()) + break; + } + relro_size += *increase_relro; + // Pad the total relro size to a multiple of the maximum + // section alignment seen. + uint64_t aligned_size = align_address(relro_size, max_align); + // Note the amount of padding added after the last relro section. + last_relro_pad = aligned_size - relro_size; + *has_relro = true; + + uint64_t page_align = parameters->target().abi_pagesize(); + + // Align to offset N such that (N + RELRO_SIZE) % PAGE_ALIGN == 0. + uint64_t desired_align = page_align - (aligned_size % page_align); + if (desired_align < *poff % page_align) + *poff += page_align - *poff % page_align; + *poff += desired_align - *poff % page_align; + addr += *poff - orig_off; + orig_off = *poff; + } + + if (!reset && this->are_addresses_set_) + { + gold_assert(this->paddr_ == addr); + addr = this->vaddr_; + } + else + { + this->vaddr_ = addr; + this->paddr_ = addr; + this->are_addresses_set_ = true; + } + + in_tls = false; + + this->offset_ = orig_off; + + off_t off = 0; + uint64_t ret; + for (int i = 0; i < static_cast<int>(ORDER_MAX); ++i) + { + if (i == static_cast<int>(ORDER_RELRO_LAST)) + { + *poff += last_relro_pad; + addr += last_relro_pad; + if (this->output_lists_[i].empty()) + { + // If there is nothing in the ORDER_RELRO_LAST list, + // the padding will occur at the end of the relro + // segment, and we need to add it to *INCREASE_RELRO. + *increase_relro += last_relro_pad; + } + } + addr = this->set_section_list_addresses(layout, reset, + &this->output_lists_[i], + addr, poff, pshndx, &in_tls); + if (i < static_cast<int>(ORDER_SMALL_BSS)) + { + this->filesz_ = *poff - orig_off; + off = *poff; + } + + ret = addr; + } + + // If the last section was a TLS section, align upward to the + // alignment of the TLS segment, so that the overall size of the TLS + // segment is aligned. + if (in_tls) + { + uint64_t segment_align = layout->tls_segment()->maximum_alignment(); + *poff = align_address(*poff, segment_align); + } + + this->memsz_ = *poff - orig_off; + + // Ignore the file offset adjustments made by the BSS Output_data + // objects. + *poff = off; + + // If code segments must contain only code, and this code segment is + // page-aligned in the file, then fill it out to a whole page with + // code fill (the tail of the segment will not be within any section). + // Thus the entire code segment can be mapped from the file as whole + // pages and that mapping will contain only valid instructions. + if (target->isolate_execinstr() && (this->flags() & elfcpp::PF_X) != 0) + { + uint64_t abi_pagesize = target->abi_pagesize(); + if (orig_off % abi_pagesize == 0 && off % abi_pagesize != 0) + { + size_t fill_size = abi_pagesize - (off % abi_pagesize); + + std::string fill_data; + if (target->has_code_fill()) + fill_data = target->code_fill(fill_size); + else + fill_data.resize(fill_size); // Zero fill. + + Output_data_const* fill = new Output_data_const(fill_data, 0); + fill->set_address(this->vaddr_ + this->memsz_); + fill->set_file_offset(off); + layout->add_relax_output(fill); + + off += fill_size; + gold_assert(off % abi_pagesize == 0); + ret += fill_size; + gold_assert(ret % abi_pagesize == 0); + + gold_assert((uint64_t) this->filesz_ == this->memsz_); + this->memsz_ = this->filesz_ += fill_size; + + *poff = off; + } + } + + return ret; +} + +// Set the addresses and file offsets in a list of Output_data +// structures. + +uint64_t +Output_segment::set_section_list_addresses(Layout* layout, bool reset, + Output_data_list* pdl, + uint64_t addr, off_t* poff, + unsigned int* pshndx, + bool* in_tls) +{ + off_t startoff = *poff; + // For incremental updates, we may allocate non-fixed sections from + // free space in the file. This keeps track of the high-water mark. + off_t maxoff = startoff; + + off_t off = startoff; + for (Output_data_list::iterator p = pdl->begin(); + p != pdl->end(); + ++p) + { + if (reset) + (*p)->reset_address_and_file_offset(); + + // When doing an incremental update or when using a linker script, + // the section will most likely already have an address. + if (!(*p)->is_address_valid()) + { + uint64_t align = (*p)->addralign(); + + if ((*p)->is_section_flag_set(elfcpp::SHF_TLS)) + { + // Give the first TLS section the alignment of the + // entire TLS segment. Otherwise the TLS segment as a + // whole may be misaligned. + if (!*in_tls) + { + Output_segment* tls_segment = layout->tls_segment(); + gold_assert(tls_segment != NULL); + uint64_t segment_align = tls_segment->maximum_alignment(); + gold_assert(segment_align >= align); + align = segment_align; + + *in_tls = true; + } + } + else + { + // If this is the first section after the TLS segment, + // align it to at least the alignment of the TLS + // segment, so that the size of the overall TLS segment + // is aligned. + if (*in_tls) + { + uint64_t segment_align = + layout->tls_segment()->maximum_alignment(); + if (segment_align > align) + align = segment_align; + + *in_tls = false; + } + } + + if (!parameters->incremental_update()) + { + off = align_address(off, align); + (*p)->set_address_and_file_offset(addr + (off - startoff), off); + } + else + { + // Incremental update: allocate file space from free list. + (*p)->pre_finalize_data_size(); + off_t current_size = (*p)->current_data_size(); + off = layout->allocate(current_size, align, startoff); + if (off == -1) + { + gold_assert((*p)->output_section() != NULL); + gold_fallback(_("out of patch space for section %s; " + "relink with --incremental-full"), + (*p)->output_section()->name()); + } + (*p)->set_address_and_file_offset(addr + (off - startoff), off); + if ((*p)->data_size() > current_size) + { + gold_assert((*p)->output_section() != NULL); + gold_fallback(_("%s: section changed size; " + "relink with --incremental-full"), + (*p)->output_section()->name()); + } + } + } + else if (parameters->incremental_update()) + { + // For incremental updates, use the fixed offset for the + // high-water mark computation. + off = (*p)->offset(); + } + else + { + // The script may have inserted a skip forward, but it + // better not have moved backward. + if ((*p)->address() >= addr + (off - startoff)) + off += (*p)->address() - (addr + (off - startoff)); + else + { + if (!layout->script_options()->saw_sections_clause()) + gold_unreachable(); + else + { + Output_section* os = (*p)->output_section(); + + // Cast to unsigned long long to avoid format warnings. + unsigned long long previous_dot = + static_cast<unsigned long long>(addr + (off - startoff)); + unsigned long long dot = + static_cast<unsigned long long>((*p)->address()); + + if (os == NULL) + gold_error(_("dot moves backward in linker script " + "from 0x%llx to 0x%llx"), previous_dot, dot); + else + gold_error(_("address of section '%s' moves backward " + "from 0x%llx to 0x%llx"), + os->name(), previous_dot, dot); + } + } + (*p)->set_file_offset(off); + (*p)->finalize_data_size(); + } + + if (parameters->incremental_update()) + gold_debug(DEBUG_INCREMENTAL, + "set_section_list_addresses: %08lx %08lx %s", + static_cast<long>(off), + static_cast<long>((*p)->data_size()), + ((*p)->output_section() != NULL + ? (*p)->output_section()->name() : "(special)")); + + // We want to ignore the size of a SHF_TLS SHT_NOBITS + // section. Such a section does not affect the size of a + // PT_LOAD segment. + if (!(*p)->is_section_flag_set(elfcpp::SHF_TLS) + || !(*p)->is_section_type(elfcpp::SHT_NOBITS)) + off += (*p)->data_size(); + + if (off > maxoff) + maxoff = off; + + if ((*p)->is_section()) + { + (*p)->set_out_shndx(*pshndx); + ++*pshndx; + } + } + + *poff = maxoff; + return addr + (maxoff - startoff); +} + +// For a non-PT_LOAD segment, set the offset from the sections, if +// any. Add INCREASE to the file size and the memory size. + +void +Output_segment::set_offset(unsigned int increase) +{ + gold_assert(this->type_ != elfcpp::PT_LOAD); + + gold_assert(!this->are_addresses_set_); + + // A non-load section only uses output_lists_[0]. + + Output_data_list* pdl = &this->output_lists_[0]; + + if (pdl->empty()) + { + gold_assert(increase == 0); + this->vaddr_ = 0; + this->paddr_ = 0; + this->are_addresses_set_ = true; + this->memsz_ = 0; + this->min_p_align_ = 0; + this->offset_ = 0; + this->filesz_ = 0; + return; + } + + // Find the first and last section by address. + const Output_data* first = NULL; + const Output_data* last_data = NULL; + const Output_data* last_bss = NULL; + for (Output_data_list::const_iterator p = pdl->begin(); + p != pdl->end(); + ++p) + { + if (first == NULL + || (*p)->address() < first->address() + || ((*p)->address() == first->address() + && (*p)->data_size() < first->data_size())) + first = *p; + const Output_data** plast; + if ((*p)->is_section() + && (*p)->output_section()->type() == elfcpp::SHT_NOBITS) + plast = &last_bss; + else + plast = &last_data; + if (*plast == NULL + || (*p)->address() > (*plast)->address() + || ((*p)->address() == (*plast)->address() + && (*p)->data_size() > (*plast)->data_size())) + *plast = *p; + } + + this->vaddr_ = first->address(); + this->paddr_ = (first->has_load_address() + ? first->load_address() + : this->vaddr_); + this->are_addresses_set_ = true; + this->offset_ = first->offset(); + + if (last_data == NULL) + this->filesz_ = 0; + else + this->filesz_ = (last_data->address() + + last_data->data_size() + - this->vaddr_); + + const Output_data* last = last_bss != NULL ? last_bss : last_data; + this->memsz_ = (last->address() + + last->data_size() + - this->vaddr_); + + this->filesz_ += increase; + this->memsz_ += increase; + + // If this is a RELRO segment, verify that the segment ends at a + // page boundary. + if (this->type_ == elfcpp::PT_GNU_RELRO) + { + uint64_t page_align = parameters->target().abi_pagesize(); + uint64_t segment_end = this->vaddr_ + this->memsz_; + if (parameters->incremental_update()) + { + // The INCREASE_RELRO calculation is bypassed for an incremental + // update, so we need to adjust the segment size manually here. + segment_end = align_address(segment_end, page_align); + this->memsz_ = segment_end - this->vaddr_; + } + else + gold_assert(segment_end == align_address(segment_end, page_align)); + } + + // If this is a TLS segment, align the memory size. The code in + // set_section_list ensures that the section after the TLS segment + // is aligned to give us room. + if (this->type_ == elfcpp::PT_TLS) + { + uint64_t segment_align = this->maximum_alignment(); + gold_assert(this->vaddr_ == align_address(this->vaddr_, segment_align)); + this->memsz_ = align_address(this->memsz_, segment_align); + } +} + +// Set the TLS offsets of the sections in the PT_TLS segment. + +void +Output_segment::set_tls_offsets() +{ + gold_assert(this->type_ == elfcpp::PT_TLS); + + for (Output_data_list::iterator p = this->output_lists_[0].begin(); + p != this->output_lists_[0].end(); + ++p) + (*p)->set_tls_offset(this->vaddr_); +} + +// Return the first section. + +Output_section* +Output_segment::first_section() const +{ + for (int i = 0; i < static_cast<int>(ORDER_MAX); ++i) + { + const Output_data_list* pdl = &this->output_lists_[i]; + for (Output_data_list::const_iterator p = pdl->begin(); + p != pdl->end(); + ++p) + { + if ((*p)->is_section()) + return (*p)->output_section(); + } + } + gold_unreachable(); +} + +// Return the number of Output_sections in an Output_segment. + +unsigned int +Output_segment::output_section_count() const +{ + unsigned int ret = 0; + for (int i = 0; i < static_cast<int>(ORDER_MAX); ++i) + ret += this->output_section_count_list(&this->output_lists_[i]); + return ret; +} + +// Return the number of Output_sections in an Output_data_list. + +unsigned int +Output_segment::output_section_count_list(const Output_data_list* pdl) const +{ + unsigned int count = 0; + for (Output_data_list::const_iterator p = pdl->begin(); + p != pdl->end(); + ++p) + { + if ((*p)->is_section()) + ++count; + } + return count; +} + +// Return the section attached to the list segment with the lowest +// load address. This is used when handling a PHDRS clause in a +// linker script. + +Output_section* +Output_segment::section_with_lowest_load_address() const +{ + Output_section* found = NULL; + uint64_t found_lma = 0; + for (int i = 0; i < static_cast<int>(ORDER_MAX); ++i) + this->lowest_load_address_in_list(&this->output_lists_[i], &found, + &found_lma); + return found; +} + +// Look through a list for a section with a lower load address. + +void +Output_segment::lowest_load_address_in_list(const Output_data_list* pdl, + Output_section** found, + uint64_t* found_lma) const +{ + for (Output_data_list::const_iterator p = pdl->begin(); + p != pdl->end(); + ++p) + { + if (!(*p)->is_section()) + continue; + Output_section* os = static_cast<Output_section*>(*p); + uint64_t lma = (os->has_load_address() + ? os->load_address() + : os->address()); + if (*found == NULL || lma < *found_lma) + { + *found = os; + *found_lma = lma; + } + } +} + +// Write the segment data into *OPHDR. + +template<int size, bool big_endian> +void +Output_segment::write_header(elfcpp::Phdr_write<size, big_endian>* ophdr) +{ + ophdr->put_p_type(this->type_); + ophdr->put_p_offset(this->offset_); + ophdr->put_p_vaddr(this->vaddr_); + ophdr->put_p_paddr(this->paddr_); + ophdr->put_p_filesz(this->filesz_); + ophdr->put_p_memsz(this->memsz_); + ophdr->put_p_flags(this->flags_); + ophdr->put_p_align(std::max(this->min_p_align_, this->maximum_alignment())); +} + +// Write the section headers into V. + +template<int size, bool big_endian> +unsigned char* +Output_segment::write_section_headers(const Layout* layout, + const Stringpool* secnamepool, + unsigned char* v, + unsigned int* pshndx) const +{ + // Every section that is attached to a segment must be attached to a + // PT_LOAD segment, so we only write out section headers for PT_LOAD + // segments. + if (this->type_ != elfcpp::PT_LOAD) + return v; + + for (int i = 0; i < static_cast<int>(ORDER_MAX); ++i) + { + const Output_data_list* pdl = &this->output_lists_[i]; + v = this->write_section_headers_list<size, big_endian>(layout, + secnamepool, + pdl, + v, pshndx); + } + + return v; +} + +template<int size, bool big_endian> +unsigned char* +Output_segment::write_section_headers_list(const Layout* layout, + const Stringpool* secnamepool, + const Output_data_list* pdl, + unsigned char* v, + unsigned int* pshndx) const +{ + const int shdr_size = elfcpp::Elf_sizes<size>::shdr_size; + for (Output_data_list::const_iterator p = pdl->begin(); + p != pdl->end(); + ++p) + { + if ((*p)->is_section()) + { + const Output_section* ps = static_cast<const Output_section*>(*p); + gold_assert(*pshndx == ps->out_shndx()); + elfcpp::Shdr_write<size, big_endian> oshdr(v); + ps->write_header(layout, secnamepool, &oshdr); + v += shdr_size; + ++*pshndx; + } + } + return v; +} + +// Print the output sections to the map file. + +void +Output_segment::print_sections_to_mapfile(Mapfile* mapfile) const +{ + if (this->type() != elfcpp::PT_LOAD) + return; + for (int i = 0; i < static_cast<int>(ORDER_MAX); ++i) + this->print_section_list_to_mapfile(mapfile, &this->output_lists_[i]); +} + +// Print an output section list to the map file. + +void +Output_segment::print_section_list_to_mapfile(Mapfile* mapfile, + const Output_data_list* pdl) const +{ + for (Output_data_list::const_iterator p = pdl->begin(); + p != pdl->end(); + ++p) + (*p)->print_to_mapfile(mapfile); +} + +// Output_file methods. + +Output_file::Output_file(const char* name) + : name_(name), + o_(-1), + file_size_(0), + base_(NULL), + map_is_anonymous_(false), + map_is_allocated_(false), + is_temporary_(false) +{ +} + +// Try to open an existing file. Returns false if the file doesn't +// exist, has a size of 0 or can't be mmapped. If BASE_NAME is not +// NULL, open that file as the base for incremental linking, and +// copy its contents to the new output file. This routine can +// be called for incremental updates, in which case WRITABLE should +// be true, or by the incremental-dump utility, in which case +// WRITABLE should be false. + +bool +Output_file::open_base_file(const char* base_name, bool writable) +{ + // The name "-" means "stdout". + if (strcmp(this->name_, "-") == 0) + return false; + + bool use_base_file = base_name != NULL; + if (!use_base_file) + base_name = this->name_; + else if (strcmp(base_name, this->name_) == 0) + gold_fatal(_("%s: incremental base and output file name are the same"), + base_name); + + // Don't bother opening files with a size of zero. + struct stat s; + if (::stat(base_name, &s) != 0) + { + gold_info(_("%s: stat: %s"), base_name, strerror(errno)); + return false; + } + if (s.st_size == 0) + { + gold_info(_("%s: incremental base file is empty"), base_name); + return false; + } + + // If we're using a base file, we want to open it read-only. + if (use_base_file) + writable = false; + + int oflags = writable ? O_RDWR : O_RDONLY; + int o = open_descriptor(-1, base_name, oflags, 0); + if (o < 0) + { + gold_info(_("%s: open: %s"), base_name, strerror(errno)); + return false; + } + + // If the base file and the output file are different, open a + // new output file and read the contents from the base file into + // the newly-mapped region. + if (use_base_file) + { + this->open(s.st_size); + ssize_t bytes_to_read = s.st_size; + unsigned char* p = this->base_; + while (bytes_to_read > 0) + { + ssize_t len = ::read(o, p, bytes_to_read); + if (len < 0) + { + gold_info(_("%s: read failed: %s"), base_name, strerror(errno)); + return false; + } + if (len == 0) + { + gold_info(_("%s: file too short: read only %lld of %lld bytes"), + base_name, + static_cast<long long>(s.st_size - bytes_to_read), + static_cast<long long>(s.st_size)); + return false; + } + p += len; + bytes_to_read -= len; + } + ::close(o); + return true; + } + + this->o_ = o; + this->file_size_ = s.st_size; + + if (!this->map_no_anonymous(writable)) + { + release_descriptor(o, true); + this->o_ = -1; + this->file_size_ = 0; + return false; + } + + return true; +} + +// Open the output file. + +void +Output_file::open(off_t file_size) +{ + this->file_size_ = file_size; + + // Unlink the file first; otherwise the open() may fail if the file + // is busy (e.g. it's an executable that's currently being executed). + // + // However, the linker may be part of a system where a zero-length + // file is created for it to write to, with tight permissions (gcc + // 2.95 did something like this). Unlinking the file would work + // around those permission controls, so we only unlink if the file + // has a non-zero size. We also unlink only regular files to avoid + // trouble with directories/etc. + // + // If we fail, continue; this command is merely a best-effort attempt + // to improve the odds for open(). + + // We let the name "-" mean "stdout" + if (!this->is_temporary_) + { + if (strcmp(this->name_, "-") == 0) + this->o_ = STDOUT_FILENO; + else + { + struct stat s; + if (::stat(this->name_, &s) == 0 + && (S_ISREG (s.st_mode) || S_ISLNK (s.st_mode))) + { + if (s.st_size != 0) + ::unlink(this->name_); + else if (!parameters->options().relocatable()) + { + // If we don't unlink the existing file, add execute + // permission where read permissions already exist + // and where the umask permits. + int mask = ::umask(0); + ::umask(mask); + s.st_mode |= (s.st_mode & 0444) >> 2; + ::chmod(this->name_, s.st_mode & ~mask); + } + } + + int mode = parameters->options().relocatable() ? 0666 : 0777; + int o = open_descriptor(-1, this->name_, O_RDWR | O_CREAT | O_TRUNC, + mode); + if (o < 0) + gold_fatal(_("%s: open: %s"), this->name_, strerror(errno)); + this->o_ = o; + } + } + + this->map(); +} + +// Resize the output file. + +void +Output_file::resize(off_t file_size) +{ + // If the mmap is mapping an anonymous memory buffer, this is easy: + // just mremap to the new size. If it's mapping to a file, we want + // to unmap to flush to the file, then remap after growing the file. + if (this->map_is_anonymous_) + { + void* base; + if (!this->map_is_allocated_) + { + base = ::mremap(this->base_, this->file_size_, file_size, + MREMAP_MAYMOVE); + if (base == MAP_FAILED) + gold_fatal(_("%s: mremap: %s"), this->name_, strerror(errno)); + } + else + { + base = realloc(this->base_, file_size); + if (base == NULL) + gold_nomem(); + if (file_size > this->file_size_) + memset(static_cast<char*>(base) + this->file_size_, 0, + file_size - this->file_size_); + } + this->base_ = static_cast<unsigned char*>(base); + this->file_size_ = file_size; + } + else + { + this->unmap(); + this->file_size_ = file_size; + if (!this->map_no_anonymous(true)) + gold_fatal(_("%s: mmap: %s"), this->name_, strerror(errno)); + } +} + +// Map an anonymous block of memory which will later be written to the +// file. Return whether the map succeeded. + +bool +Output_file::map_anonymous() +{ + void* base = ::mmap(NULL, this->file_size_, PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + if (base == MAP_FAILED) + { + base = malloc(this->file_size_); + if (base == NULL) + return false; + memset(base, 0, this->file_size_); + this->map_is_allocated_ = true; + } + this->base_ = static_cast<unsigned char*>(base); + this->map_is_anonymous_ = true; + return true; +} + +// Map the file into memory. Return whether the mapping succeeded. +// If WRITABLE is true, map with write access. + +bool +Output_file::map_no_anonymous(bool writable) +{ + const int o = this->o_; + + // If the output file is not a regular file, don't try to mmap it; + // instead, we'll mmap a block of memory (an anonymous buffer), and + // then later write the buffer to the file. + void* base; + struct stat statbuf; + if (o == STDOUT_FILENO || o == STDERR_FILENO + || ::fstat(o, &statbuf) != 0 + || !S_ISREG(statbuf.st_mode) + || this->is_temporary_) + return false; + + // Ensure that we have disk space available for the file. If we + // don't do this, it is possible that we will call munmap, close, + // and exit with dirty buffers still in the cache with no assigned + // disk blocks. If the disk is out of space at that point, the + // output file will wind up incomplete, but we will have already + // exited. The alternative to fallocate would be to use fdatasync, + // but that would be a more significant performance hit. + if (writable) + { + int err = gold_fallocate(o, 0, this->file_size_); + if (err != 0) + gold_fatal(_("%s: %s"), this->name_, strerror(err)); + } + + // Map the file into memory. + int prot = PROT_READ; + if (writable) + prot |= PROT_WRITE; + base = ::mmap(NULL, this->file_size_, prot, MAP_SHARED, o, 0); + + // The mmap call might fail because of file system issues: the file + // system might not support mmap at all, or it might not support + // mmap with PROT_WRITE. + if (base == MAP_FAILED) + return false; + + this->map_is_anonymous_ = false; + this->base_ = static_cast<unsigned char*>(base); + return true; +} + +// Map the file into memory. + +void +Output_file::map() +{ + if (parameters->options().mmap_output_file() + && this->map_no_anonymous(true)) + return; + + // The mmap call might fail because of file system issues: the file + // system might not support mmap at all, or it might not support + // mmap with PROT_WRITE. I'm not sure which errno values we will + // see in all cases, so if the mmap fails for any reason and we + // don't care about file contents, try for an anonymous map. + if (this->map_anonymous()) + return; + + gold_fatal(_("%s: mmap: failed to allocate %lu bytes for output file: %s"), + this->name_, static_cast<unsigned long>(this->file_size_), + strerror(errno)); +} + +// Unmap the file from memory. + +void +Output_file::unmap() +{ + if (this->map_is_anonymous_) + { + // We've already written out the data, so there is no reason to + // waste time unmapping or freeing the memory. + } + else + { + if (::munmap(this->base_, this->file_size_) < 0) + gold_error(_("%s: munmap: %s"), this->name_, strerror(errno)); + } + this->base_ = NULL; +} + +// Close the output file. + +void +Output_file::close() +{ + // If the map isn't file-backed, we need to write it now. + if (this->map_is_anonymous_ && !this->is_temporary_) + { + size_t bytes_to_write = this->file_size_; + size_t offset = 0; + while (bytes_to_write > 0) + { + ssize_t bytes_written = ::write(this->o_, this->base_ + offset, + bytes_to_write); + if (bytes_written == 0) + gold_error(_("%s: write: unexpected 0 return-value"), this->name_); + else if (bytes_written < 0) + gold_error(_("%s: write: %s"), this->name_, strerror(errno)); + else + { + bytes_to_write -= bytes_written; + offset += bytes_written; + } + } + } + this->unmap(); + + // We don't close stdout or stderr + if (this->o_ != STDOUT_FILENO + && this->o_ != STDERR_FILENO + && !this->is_temporary_) + if (::close(this->o_) < 0) + gold_error(_("%s: close: %s"), this->name_, strerror(errno)); + this->o_ = -1; +} + +// Instantiate the templates we need. We could use the configure +// script to restrict this to only the ones for implemented targets. + +#ifdef HAVE_TARGET_32_LITTLE +template +off_t +Output_section::add_input_section<32, false>( + Layout* layout, + Sized_relobj_file<32, false>* object, + unsigned int shndx, + const char* secname, + const elfcpp::Shdr<32, false>& shdr, + unsigned int reloc_shndx, + bool have_sections_script); +#endif + +#ifdef HAVE_TARGET_32_BIG +template +off_t +Output_section::add_input_section<32, true>( + Layout* layout, + Sized_relobj_file<32, true>* object, + unsigned int shndx, + const char* secname, + const elfcpp::Shdr<32, true>& shdr, + unsigned int reloc_shndx, + bool have_sections_script); +#endif + +#ifdef HAVE_TARGET_64_LITTLE +template +off_t +Output_section::add_input_section<64, false>( + Layout* layout, + Sized_relobj_file<64, false>* object, + unsigned int shndx, + const char* secname, + const elfcpp::Shdr<64, false>& shdr, + unsigned int reloc_shndx, + bool have_sections_script); +#endif + +#ifdef HAVE_TARGET_64_BIG +template +off_t +Output_section::add_input_section<64, true>( + Layout* layout, + Sized_relobj_file<64, true>* object, + unsigned int shndx, + const char* secname, + const elfcpp::Shdr<64, true>& shdr, + unsigned int reloc_shndx, + bool have_sections_script); +#endif + +#ifdef HAVE_TARGET_32_LITTLE +template +class Output_reloc<elfcpp::SHT_REL, false, 32, false>; +#endif + +#ifdef HAVE_TARGET_32_BIG +template +class Output_reloc<elfcpp::SHT_REL, false, 32, true>; +#endif + +#ifdef HAVE_TARGET_64_LITTLE +template +class Output_reloc<elfcpp::SHT_REL, false, 64, false>; +#endif + +#ifdef HAVE_TARGET_64_BIG +template +class Output_reloc<elfcpp::SHT_REL, false, 64, true>; +#endif + +#ifdef HAVE_TARGET_32_LITTLE +template +class Output_reloc<elfcpp::SHT_REL, true, 32, false>; +#endif + +#ifdef HAVE_TARGET_32_BIG +template +class Output_reloc<elfcpp::SHT_REL, true, 32, true>; +#endif + +#ifdef HAVE_TARGET_64_LITTLE +template +class Output_reloc<elfcpp::SHT_REL, true, 64, false>; +#endif + +#ifdef HAVE_TARGET_64_BIG +template +class Output_reloc<elfcpp::SHT_REL, true, 64, true>; +#endif + +#ifdef HAVE_TARGET_32_LITTLE +template +class Output_reloc<elfcpp::SHT_RELA, false, 32, false>; +#endif + +#ifdef HAVE_TARGET_32_BIG +template +class Output_reloc<elfcpp::SHT_RELA, false, 32, true>; +#endif + +#ifdef HAVE_TARGET_64_LITTLE +template +class Output_reloc<elfcpp::SHT_RELA, false, 64, false>; +#endif + +#ifdef HAVE_TARGET_64_BIG +template +class Output_reloc<elfcpp::SHT_RELA, false, 64, true>; +#endif + +#ifdef HAVE_TARGET_32_LITTLE +template +class Output_reloc<elfcpp::SHT_RELA, true, 32, false>; +#endif + +#ifdef HAVE_TARGET_32_BIG +template +class Output_reloc<elfcpp::SHT_RELA, true, 32, true>; +#endif + +#ifdef HAVE_TARGET_64_LITTLE +template +class Output_reloc<elfcpp::SHT_RELA, true, 64, false>; +#endif + +#ifdef HAVE_TARGET_64_BIG +template +class Output_reloc<elfcpp::SHT_RELA, true, 64, true>; +#endif + +#ifdef HAVE_TARGET_32_LITTLE +template +class Output_data_reloc<elfcpp::SHT_REL, false, 32, false>; +#endif + +#ifdef HAVE_TARGET_32_BIG +template +class Output_data_reloc<elfcpp::SHT_REL, false, 32, true>; +#endif + +#ifdef HAVE_TARGET_64_LITTLE +template +class Output_data_reloc<elfcpp::SHT_REL, false, 64, false>; +#endif + +#ifdef HAVE_TARGET_64_BIG +template +class Output_data_reloc<elfcpp::SHT_REL, false, 64, true>; +#endif + +#ifdef HAVE_TARGET_32_LITTLE +template +class Output_data_reloc<elfcpp::SHT_REL, true, 32, false>; +#endif + +#ifdef HAVE_TARGET_32_BIG +template +class Output_data_reloc<elfcpp::SHT_REL, true, 32, true>; +#endif + +#ifdef HAVE_TARGET_64_LITTLE +template +class Output_data_reloc<elfcpp::SHT_REL, true, 64, false>; +#endif + +#ifdef HAVE_TARGET_64_BIG +template +class Output_data_reloc<elfcpp::SHT_REL, true, 64, true>; +#endif + +#ifdef HAVE_TARGET_32_LITTLE +template +class Output_data_reloc<elfcpp::SHT_RELA, false, 32, false>; +#endif + +#ifdef HAVE_TARGET_32_BIG +template +class Output_data_reloc<elfcpp::SHT_RELA, false, 32, true>; +#endif + +#ifdef HAVE_TARGET_64_LITTLE +template +class Output_data_reloc<elfcpp::SHT_RELA, false, 64, false>; +#endif + +#ifdef HAVE_TARGET_64_BIG +template +class Output_data_reloc<elfcpp::SHT_RELA, false, 64, true>; +#endif + +#ifdef HAVE_TARGET_32_LITTLE +template +class Output_data_reloc<elfcpp::SHT_RELA, true, 32, false>; +#endif + +#ifdef HAVE_TARGET_32_BIG +template +class Output_data_reloc<elfcpp::SHT_RELA, true, 32, true>; +#endif + +#ifdef HAVE_TARGET_64_LITTLE +template +class Output_data_reloc<elfcpp::SHT_RELA, true, 64, false>; +#endif + +#ifdef HAVE_TARGET_64_BIG +template +class Output_data_reloc<elfcpp::SHT_RELA, true, 64, true>; +#endif + +#ifdef HAVE_TARGET_32_LITTLE +template +class Output_relocatable_relocs<elfcpp::SHT_REL, 32, false>; +#endif + +#ifdef HAVE_TARGET_32_BIG +template +class Output_relocatable_relocs<elfcpp::SHT_REL, 32, true>; +#endif + +#ifdef HAVE_TARGET_64_LITTLE +template +class Output_relocatable_relocs<elfcpp::SHT_REL, 64, false>; +#endif + +#ifdef HAVE_TARGET_64_BIG +template +class Output_relocatable_relocs<elfcpp::SHT_REL, 64, true>; +#endif + +#ifdef HAVE_TARGET_32_LITTLE +template +class Output_relocatable_relocs<elfcpp::SHT_RELA, 32, false>; +#endif + +#ifdef HAVE_TARGET_32_BIG +template +class Output_relocatable_relocs<elfcpp::SHT_RELA, 32, true>; +#endif + +#ifdef HAVE_TARGET_64_LITTLE +template +class Output_relocatable_relocs<elfcpp::SHT_RELA, 64, false>; +#endif + +#ifdef HAVE_TARGET_64_BIG +template +class Output_relocatable_relocs<elfcpp::SHT_RELA, 64, true>; +#endif + +#ifdef HAVE_TARGET_32_LITTLE +template +class Output_data_group<32, false>; +#endif + +#ifdef HAVE_TARGET_32_BIG +template +class Output_data_group<32, true>; +#endif + +#ifdef HAVE_TARGET_64_LITTLE +template +class Output_data_group<64, false>; +#endif + +#ifdef HAVE_TARGET_64_BIG +template +class Output_data_group<64, true>; +#endif + +template +class Output_data_got<32, false>; + +template +class Output_data_got<32, true>; + +template +class Output_data_got<64, false>; + +template +class Output_data_got<64, true>; + +} // End namespace gold. |