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gnu / binutils-gdb / c599303f92b1edd6ead3947737a8ae9e1c85e08c / . / gold / incremental.cc
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// inremental.cc -- incremental linking support for gold
// Copyright (C) 2009-2021 Free Software Foundation, Inc.
// Written by Mikolaj Zalewski <mikolajz@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 <set>
#include <cstdarg>
#include "libiberty.h"
#include "elfcpp.h"
#include "options.h"
#include "output.h"
#include "symtab.h"
#include "incremental.h"
#include "archive.h"
#include "object.h"
#include "target-select.h"
#include "target.h"
#include "fileread.h"
#include "script.h"
namespace gold {
// Version number for the .gnu_incremental_inputs section.
// Version 1 was the initial checkin.
// Version 2 adds some padding to ensure 8-byte alignment where necessary.
const unsigned int INCREMENTAL_LINK_VERSION = 2;
// This class manages the .gnu_incremental_inputs section, which holds
// the header information, a directory of input files, and separate
// entries for each input file.
template<int size, bool big_endian>
class Output_section_incremental_inputs : public Output_section_data
{
public:
Output_section_incremental_inputs(const Incremental_inputs* inputs,
const Symbol_table* symtab)
: Output_section_data(size / 8), inputs_(inputs), symtab_(symtab)
{ }
protected:
// This is called to update the section size prior to assigning
// the address and file offset.
void
update_data_size()
{ this->set_final_data_size(); }
// Set the final data size.
void
set_final_data_size();
// Write the data to the file.
void
do_write(Output_file*);
// Write to a map file.
void
do_print_to_mapfile(Mapfile* mapfile) const
{ mapfile->print_output_data(this, _("** incremental_inputs")); }
private:
// Write the section header.
unsigned char*
write_header(unsigned char* pov, unsigned int input_file_count,
section_offset_type command_line_offset);
// Write the input file entries.
unsigned char*
write_input_files(unsigned char* oview, unsigned char* pov,
Stringpool* strtab);
// Write the supplemental information blocks.
unsigned char*
write_info_blocks(unsigned char* oview, unsigned char* pov,
Stringpool* strtab, unsigned int* global_syms,
unsigned int global_sym_count);
// Write the contents of the .gnu_incremental_symtab section.
void
write_symtab(unsigned char* pov, unsigned int* global_syms,
unsigned int global_sym_count);
// Write the contents of the .gnu_incremental_got_plt section.
void
write_got_plt(unsigned char* pov, off_t view_size);
// Typedefs for writing the data to the output sections.
typedef elfcpp::Swap<size, big_endian> Swap;
typedef elfcpp::Swap<16, big_endian> Swap16;
typedef elfcpp::Swap<32, big_endian> Swap32;
typedef elfcpp::Swap<64, big_endian> Swap64;
// Sizes of various structures.
static const int sizeof_addr = size / 8;
static const int header_size =
Incremental_inputs_reader<size, big_endian>::header_size;
static const int input_entry_size =
Incremental_inputs_reader<size, big_endian>::input_entry_size;
static const unsigned int object_info_size =
Incremental_inputs_reader<size, big_endian>::object_info_size;
static const unsigned int input_section_entry_size =
Incremental_inputs_reader<size, big_endian>::input_section_entry_size;
static const unsigned int global_sym_entry_size =
Incremental_inputs_reader<size, big_endian>::global_sym_entry_size;
static const unsigned int incr_reloc_size =
Incremental_relocs_reader<size, big_endian>::reloc_size;
// The Incremental_inputs object.
const Incremental_inputs* inputs_;
// The symbol table.
const Symbol_table* symtab_;
};
// Inform the user why we don't do an incremental link. Not called in
// the obvious case of missing output file. TODO: Is this helpful?
void
vexplain_no_incremental(const char* format, va_list args)
{
char* buf = NULL;
if (vasprintf(&buf, format, args) < 0)
gold_nomem();
gold_info(_("the link might take longer: "
"cannot perform incremental link: %s"), buf);
free(buf);
}
void
explain_no_incremental(const char* format, ...)
{
va_list args;
va_start(args, format);
vexplain_no_incremental(format, args);
va_end(args);
}
// Report an error.
void
Incremental_binary::error(const char* format, ...) const
{
va_list args;
va_start(args, format);
// Current code only checks if the file can be used for incremental linking,
// so errors shouldn't fail the build, but only result in a fallback to a
// full build.
// TODO: when we implement incremental editing of the file, we may need a
// flag that will cause errors to be treated seriously.
vexplain_no_incremental(format, args);
va_end(args);
}
// Return TRUE if a section of type SH_TYPE can be updated in place
// during an incremental update. We can update sections of type PROGBITS,
// NOBITS, INIT_ARRAY, FINI_ARRAY, PREINIT_ARRAY, NOTE, and
// (processor-specific) unwind sections. All others will be regenerated.
bool
can_incremental_update(unsigned int sh_type)
{
return (sh_type == elfcpp::SHT_PROGBITS
|| sh_type == elfcpp::SHT_NOBITS
|| sh_type == elfcpp::SHT_INIT_ARRAY
|| sh_type == elfcpp::SHT_FINI_ARRAY
|| sh_type == elfcpp::SHT_PREINIT_ARRAY
|| sh_type == elfcpp::SHT_NOTE
|| sh_type == parameters->target().unwind_section_type());
}
// Find the .gnu_incremental_inputs section and related sections.
template<int size, bool big_endian>
bool
Sized_incremental_binary<size, big_endian>::find_incremental_inputs_sections(
unsigned int* p_inputs_shndx,
unsigned int* p_symtab_shndx,
unsigned int* p_relocs_shndx,
unsigned int* p_got_plt_shndx,
unsigned int* p_strtab_shndx)
{
unsigned int inputs_shndx =
this->elf_file_.find_section_by_type(elfcpp::SHT_GNU_INCREMENTAL_INPUTS);
if (inputs_shndx == elfcpp::SHN_UNDEF) // Not found.
return false;
unsigned int symtab_shndx =
this->elf_file_.find_section_by_type(elfcpp::SHT_GNU_INCREMENTAL_SYMTAB);
if (symtab_shndx == elfcpp::SHN_UNDEF) // Not found.
return false;
if (this->elf_file_.section_link(symtab_shndx) != inputs_shndx)
return false;
unsigned int relocs_shndx =
this->elf_file_.find_section_by_type(elfcpp::SHT_GNU_INCREMENTAL_RELOCS);
if (relocs_shndx == elfcpp::SHN_UNDEF) // Not found.
return false;
if (this->elf_file_.section_link(relocs_shndx) != inputs_shndx)
return false;
unsigned int got_plt_shndx =
this->elf_file_.find_section_by_type(elfcpp::SHT_GNU_INCREMENTAL_GOT_PLT);
if (got_plt_shndx == elfcpp::SHN_UNDEF) // Not found.
return false;
if (this->elf_file_.section_link(got_plt_shndx) != inputs_shndx)
return false;
unsigned int strtab_shndx = this->elf_file_.section_link(inputs_shndx);
if (strtab_shndx == elfcpp::SHN_UNDEF
|| strtab_shndx > this->elf_file_.shnum()
|| this->elf_file_.section_type(strtab_shndx) != elfcpp::SHT_STRTAB)
return false;
if (p_inputs_shndx != NULL)
*p_inputs_shndx = inputs_shndx;
if (p_symtab_shndx != NULL)
*p_symtab_shndx = symtab_shndx;
if (p_relocs_shndx != NULL)
*p_relocs_shndx = relocs_shndx;
if (p_got_plt_shndx != NULL)
*p_got_plt_shndx = got_plt_shndx;
if (p_strtab_shndx != NULL)
*p_strtab_shndx = strtab_shndx;
return true;
}
// Set up the readers into the incremental info sections.
template<int size, bool big_endian>
void
Sized_incremental_binary<size, big_endian>::setup_readers()
{
unsigned int inputs_shndx;
unsigned int symtab_shndx;
unsigned int relocs_shndx;
unsigned int got_plt_shndx;
unsigned int strtab_shndx;
if (!this->find_incremental_inputs_sections(&inputs_shndx, &symtab_shndx,
&relocs_shndx, &got_plt_shndx,
&strtab_shndx))
return;
Location inputs_location(this->elf_file_.section_contents(inputs_shndx));
Location symtab_location(this->elf_file_.section_contents(symtab_shndx));
Location relocs_location(this->elf_file_.section_contents(relocs_shndx));
Location got_plt_location(this->elf_file_.section_contents(got_plt_shndx));
Location strtab_location(this->elf_file_.section_contents(strtab_shndx));
View inputs_view = this->view(inputs_location);
View symtab_view = this->view(symtab_location);
View relocs_view = this->view(relocs_location);
View got_plt_view = this->view(got_plt_location);
View strtab_view = this->view(strtab_location);
elfcpp::Elf_strtab strtab(strtab_view.data(), strtab_location.data_size);
this->inputs_reader_ =
Incremental_inputs_reader<size, big_endian>(inputs_view.data(), strtab);
this->symtab_reader_ =
Incremental_symtab_reader<big_endian>(symtab_view.data(),
symtab_location.data_size);
this->relocs_reader_ =
Incremental_relocs_reader<size, big_endian>(relocs_view.data(),
relocs_location.data_size);
this->got_plt_reader_ =
Incremental_got_plt_reader<big_endian>(got_plt_view.data());
// Find the main symbol table.
unsigned int main_symtab_shndx =
this->elf_file_.find_section_by_type(elfcpp::SHT_SYMTAB);
gold_assert(main_symtab_shndx != elfcpp::SHN_UNDEF);
this->main_symtab_loc_ = this->elf_file_.section_contents(main_symtab_shndx);
// Find the main symbol string table.
unsigned int main_strtab_shndx =
this->elf_file_.section_link(main_symtab_shndx);
gold_assert(main_strtab_shndx != elfcpp::SHN_UNDEF
&& main_strtab_shndx < this->elf_file_.shnum());
this->main_strtab_loc_ = this->elf_file_.section_contents(main_strtab_shndx);
// Walk the list of input files (a) to setup an Input_reader for each
// input file, and (b) to record maps of files added from archive
// libraries and scripts.
Incremental_inputs_reader<size, big_endian>& inputs = this->inputs_reader_;
unsigned int count = inputs.input_file_count();
this->input_objects_.resize(count);
this->input_entry_readers_.reserve(count);
this->library_map_.resize(count);
this->script_map_.resize(count);
for (unsigned int i = 0; i < count; i++)
{
Input_entry_reader input_file = inputs.input_file(i);
#if __cplusplus >= 2001103L
this->input_entry_readers_.emplace_back(input_file);
#else
this->input_entry_readers_.push_back(Sized_input_reader(input_file));
#endif
switch (input_file.type())
{
case INCREMENTAL_INPUT_OBJECT:
case INCREMENTAL_INPUT_ARCHIVE_MEMBER:
case INCREMENTAL_INPUT_SHARED_LIBRARY:
// No special treatment necessary.
break;
case INCREMENTAL_INPUT_ARCHIVE:
{
Incremental_library* lib =
new Incremental_library(input_file.filename(), i,
&this->input_entry_readers_[i]);
this->library_map_[i] = lib;
unsigned int member_count = input_file.get_member_count();
for (unsigned int j = 0; j < member_count; j++)
{
int member_offset = input_file.get_member_offset(j);
int member_index = inputs.input_file_index(member_offset);
this->library_map_[member_index] = lib;
}
}
break;
case INCREMENTAL_INPUT_SCRIPT:
{
Script_info* script = new Script_info(input_file.filename(), i);
this->script_map_[i] = script;
unsigned int object_count = input_file.get_object_count();
for (unsigned int j = 0; j < object_count; j++)
{
int object_offset = input_file.get_object_offset(j);
int object_index = inputs.input_file_index(object_offset);
this->script_map_[object_index] = script;
}
}
break;
default:
gold_unreachable();
}
}
// Initialize the map of global symbols.
unsigned int nglobals = this->symtab_reader_.symbol_count();
this->symbol_map_.resize(nglobals);
this->has_incremental_info_ = true;
}
// Walk the list of input files given on the command line, and build
// a direct map of file index to the corresponding input argument.
void
check_input_args(std::vector<const Input_argument*>& input_args_map,
Input_arguments::const_iterator begin,
Input_arguments::const_iterator end)
{
for (Input_arguments::const_iterator p = begin;
p != end;
++p)
{
if (p->is_group())
{
const Input_file_group* group = p->group();
check_input_args(input_args_map, group->begin(), group->end());
}
else if (p->is_lib())
{
const Input_file_lib* lib = p->lib();
check_input_args(input_args_map, lib->begin(), lib->end());
}
else
{
gold_assert(p->is_file());
unsigned int arg_serial = p->file().arg_serial();
if (arg_serial > 0)
{
gold_assert(arg_serial <= input_args_map.size());
gold_assert(input_args_map[arg_serial - 1] == 0);
input_args_map[arg_serial - 1] = &*p;
}
}
}
}
// Determine whether an incremental link based on the existing output file
// can be done.
template<int size, bool big_endian>
bool
Sized_incremental_binary<size, big_endian>::do_check_inputs(
const Command_line& cmdline,
Incremental_inputs* incremental_inputs)
{
Incremental_inputs_reader<size, big_endian>& inputs = this->inputs_reader_;
if (!this->has_incremental_info_)
{
explain_no_incremental(_("no incremental data from previous build"));
return false;
}
if (inputs.version() != INCREMENTAL_LINK_VERSION)
{
explain_no_incremental(_("different version of incremental build data"));
return false;
}
if (incremental_inputs->command_line() != inputs.command_line())
{
gold_debug(DEBUG_INCREMENTAL,
"old command line: %s",
inputs.command_line());
gold_debug(DEBUG_INCREMENTAL,
"new command line: %s",
incremental_inputs->command_line().c_str());
explain_no_incremental(_("command line changed"));
return false;
}
// Walk the list of input files given on the command line, and build
// a direct map of argument serial numbers to the corresponding input
// arguments.
this->input_args_map_.resize(cmdline.number_of_input_files());
check_input_args(this->input_args_map_, cmdline.begin(), cmdline.end());
// Walk the list of input files to check for conditions that prevent
// an incremental update link.
unsigned int count = inputs.input_file_count();
for (unsigned int i = 0; i < count; i++)
{
Input_entry_reader input_file = inputs.input_file(i);
switch (input_file.type())
{
case INCREMENTAL_INPUT_OBJECT:
case INCREMENTAL_INPUT_ARCHIVE_MEMBER:
case INCREMENTAL_INPUT_SHARED_LIBRARY:
case INCREMENTAL_INPUT_ARCHIVE:
// No special treatment necessary.
break;
case INCREMENTAL_INPUT_SCRIPT:
if (this->do_file_has_changed(i))
{
explain_no_incremental(_("%s: script file changed"),
input_file.filename());
return false;
}
break;
default:
gold_unreachable();
}
}
return true;
}
// Return TRUE if input file N has changed since the last incremental link.
template<int size, bool big_endian>
bool
Sized_incremental_binary<size, big_endian>::do_file_has_changed(
unsigned int n) const
{
Input_entry_reader input_file = this->inputs_reader_.input_file(n);
Incremental_disposition disp = INCREMENTAL_CHECK;
// For files named in scripts, find the file that was actually named
// on the command line, so that we can get the incremental disposition
// flag.
Script_info* script = this->get_script_info(n);
if (script != NULL)
n = script->input_file_index();
const Input_argument* input_argument = this->get_input_argument(n);
if (input_argument != NULL)
disp = input_argument->file().options().incremental_disposition();
// For files at the beginning of the command line (i.e., those added
// implicitly by gcc), check whether the --incremental-startup-unchanged
// option was used.
if (disp == INCREMENTAL_STARTUP)
disp = parameters->options().incremental_startup_disposition();
if (disp != INCREMENTAL_CHECK)
return disp == INCREMENTAL_CHANGED;
const char* filename = input_file.filename();
Timespec old_mtime = input_file.get_mtime();
Timespec new_mtime;
if (!get_mtime(filename, &new_mtime))
{
// If we can't open get the current modification time, assume it has
// changed. If the file doesn't exist, we'll issue an error when we
// try to open it later.
return true;
}
if (new_mtime.seconds > old_mtime.seconds)
return true;
if (new_mtime.seconds == old_mtime.seconds
&& new_mtime.nanoseconds > old_mtime.nanoseconds)
return true;
return false;
}
// Initialize the layout of the output file based on the existing
// output file.
template<int size, bool big_endian>
void
Sized_incremental_binary<size, big_endian>::do_init_layout(Layout* layout)
{
typedef elfcpp::Shdr<size, big_endian> Shdr;
const int shdr_size = elfcpp::Elf_sizes<size>::shdr_size;
// Get views of the section headers and the section string table.
const off_t shoff = this->elf_file_.shoff();
const unsigned int shnum = this->elf_file_.shnum();
const unsigned int shstrndx = this->elf_file_.shstrndx();
Location shdrs_location(shoff, shnum * shdr_size);
Location shstrndx_location(this->elf_file_.section_contents(shstrndx));
View shdrs_view = this->view(shdrs_location);
View shstrndx_view = this->view(shstrndx_location);
elfcpp::Elf_strtab shstrtab(shstrndx_view.data(),
shstrndx_location.data_size);
layout->set_incremental_base(this);
// Initialize the layout.
this->section_map_.resize(shnum);
const unsigned char* pshdr = shdrs_view.data() + shdr_size;
for (unsigned int i = 1; i < shnum; i++)
{
Shdr shdr(pshdr);
const char* name;
if (!shstrtab.get_c_string(shdr.get_sh_name(), &name))
name = NULL;
gold_debug(DEBUG_INCREMENTAL,
"Output section: %2d %08lx %08lx %08lx %3d %s",
i,
static_cast<long>(shdr.get_sh_addr()),
static_cast<long>(shdr.get_sh_offset()),
static_cast<long>(shdr.get_sh_size()),
shdr.get_sh_type(), name ? name : "<null>");
this->section_map_[i] = layout->init_fixed_output_section(name, shdr);
pshdr += shdr_size;
}
}
// Mark regions of the input file that must be kept unchanged.
template<int size, bool big_endian>
void
Sized_incremental_binary<size, big_endian>::do_reserve_layout(
unsigned int input_file_index)
{
const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
Input_entry_reader input_file =
this->inputs_reader_.input_file(input_file_index);
if (input_file.type() == INCREMENTAL_INPUT_SHARED_LIBRARY)
{
// Reserve the BSS space used for COPY relocations.
unsigned int nsyms = input_file.get_global_symbol_count();
Incremental_binary::View symtab_view(NULL);
unsigned int symtab_count;
elfcpp::Elf_strtab strtab(NULL, 0);
this->get_symtab_view(&symtab_view, &symtab_count, &strtab);
for (unsigned int i = 0; i < nsyms; ++i)
{
bool is_def;
bool is_copy;
unsigned int output_symndx =
input_file.get_output_symbol_index(i, &is_def, &is_copy);
if (is_copy)
{
const unsigned char* sym_p = (symtab_view.data()
+ output_symndx * sym_size);
elfcpp::Sym<size, big_endian> gsym(sym_p);
unsigned int shndx = gsym.get_st_shndx();
if (shndx < 1 || shndx >= this->section_map_.size())
continue;
Output_section* os = this->section_map_[shndx];
off_t offset = gsym.get_st_value() - os->address();
os->reserve(offset, gsym.get_st_size());
gold_debug(DEBUG_INCREMENTAL,
"Reserve for COPY reloc: %s, off %d, size %d",
os->name(),
static_cast<int>(offset),
static_cast<int>(gsym.get_st_size()));
}
}
return;
}
unsigned int shnum = input_file.get_input_section_count();
for (unsigned int i = 0; i < shnum; i++)
{
typename Input_entry_reader::Input_section_info sect =
input_file.get_input_section(i);
if (sect.output_shndx == 0 || sect.sh_offset == -1)
continue;
Output_section* os = this->section_map_[sect.output_shndx];
gold_assert(os != NULL);
os->reserve(sect.sh_offset, sect.sh_size);
}
}
// Process the GOT and PLT entries from the existing output file.
template<int size, bool big_endian>
void
Sized_incremental_binary<size, big_endian>::do_process_got_plt(
Symbol_table* symtab,
Layout* layout)
{
Incremental_got_plt_reader<big_endian> got_plt_reader(this->got_plt_reader());
Sized_target<size, big_endian>* target =
parameters->sized_target<size, big_endian>();
// Get the number of symbols in the main symbol table and in the
// incremental symbol table. The difference between the two counts
// is the index of the first forced-local or global symbol in the
// main symbol table.
unsigned int symtab_count =
this->main_symtab_loc_.data_size / elfcpp::Elf_sizes<size>::sym_size;
unsigned int isym_count = this->symtab_reader_.symbol_count();
unsigned int first_global = symtab_count - isym_count;
// Tell the target how big the GOT and PLT sections are.
unsigned int got_count = got_plt_reader.get_got_entry_count();
unsigned int plt_count = got_plt_reader.get_plt_entry_count();
Output_data_got_base* got =
target->init_got_plt_for_update(symtab, layout, got_count, plt_count);
// Read the GOT entries from the base file and build the outgoing GOT.
for (unsigned int i = 0; i < got_count; ++i)
{
unsigned int got_type = got_plt_reader.get_got_type(i);
if ((got_type & 0x7f) == 0x7f)
{
// This is the second entry of a pair.
got->reserve_slot(i);
continue;
}
unsigned int symndx = got_plt_reader.get_got_symndx(i);
if (got_type & 0x80)
{
// This is an entry for a local symbol. Ignore this entry if
// the object file was replaced.
unsigned int input_index = got_plt_reader.get_got_input_index(i);
gold_debug(DEBUG_INCREMENTAL,
"GOT entry %d, type %02x: (local symbol)",
i, got_type & 0x7f);
Sized_relobj_incr<size, big_endian>* obj =
this->input_object(input_index);
if (obj != NULL)
target->reserve_local_got_entry(i, obj, symndx, got_type & 0x7f);
}
else
{
// This is an entry for a global symbol. GOT_DESC is the symbol
// table index.
// FIXME: This should really be a fatal error (corrupt input).
gold_assert(symndx >= first_global && symndx < symtab_count);
Symbol* sym = this->global_symbol(symndx - first_global);
// Add the GOT entry only if the symbol is still referenced.
if (sym != NULL && sym->in_reg())
{
gold_debug(DEBUG_INCREMENTAL,
"GOT entry %d, type %02x: %s",
i, got_type, sym->name());
target->reserve_global_got_entry(i, sym, got_type);
}
}
}
// Read the PLT entries from the base file and pass each to the target.
for (unsigned int i = 0; i < plt_count; ++i)
{
unsigned int plt_desc = got_plt_reader.get_plt_desc(i);
// FIXME: This should really be a fatal error (corrupt input).
gold_assert(plt_desc >= first_global && plt_desc < symtab_count);
Symbol* sym = this->global_symbol(plt_desc - first_global);
// Add the PLT entry only if the symbol is still referenced.
if (sym != NULL && sym->in_reg())
{
gold_debug(DEBUG_INCREMENTAL,
"PLT entry %d: %s",
i, sym->name());
target->register_global_plt_entry(symtab, layout, i, sym);
}
}
}
// Emit COPY relocations from the existing output file.
template<int size, bool big_endian>
void
Sized_incremental_binary<size, big_endian>::do_emit_copy_relocs(
Symbol_table* symtab)
{
Sized_target<size, big_endian>* target =
parameters->sized_target<size, big_endian>();
for (typename Copy_relocs::iterator p = this->copy_relocs_.begin();
p != this->copy_relocs_.end();
++p)
{
if (!(*p).symbol->is_copied_from_dynobj())
target->emit_copy_reloc(symtab, (*p).symbol, (*p).output_section,
(*p).offset);
}
}
// Apply incremental relocations for symbols whose values have changed.
template<int size, bool big_endian>
void
Sized_incremental_binary<size, big_endian>::do_apply_incremental_relocs(
const Symbol_table* symtab,
Layout* layout,
Output_file* of)
{
typedef typename elfcpp::Elf_types<size>::Elf_Addr Address;
typedef typename elfcpp::Elf_types<size>::Elf_Swxword Addend;
Incremental_symtab_reader<big_endian> isymtab(this->symtab_reader());
Incremental_relocs_reader<size, big_endian> irelocs(this->relocs_reader());
unsigned int nglobals = isymtab.symbol_count();
const unsigned int incr_reloc_size = irelocs.reloc_size;
Relocate_info<size, big_endian> relinfo;
relinfo.symtab = symtab;
relinfo.layout = layout;
relinfo.object = NULL;
relinfo.reloc_shndx = 0;
relinfo.reloc_shdr = NULL;
relinfo.data_shndx = 0;
relinfo.data_shdr = NULL;
Sized_target<size, big_endian>* target =
parameters->sized_target<size, big_endian>();
for (unsigned int i = 0; i < nglobals; i++)
{
const Symbol* gsym = this->global_symbol(i);
// If the symbol is not referenced from any unchanged input files,
// we do not need to reapply any of its relocations.
if (gsym == NULL)
continue;
// If the symbol is defined in an unchanged file, we do not need to
// reapply any of its relocations.
if (gsym->source() == Symbol::FROM_OBJECT
&& gsym->object()->is_incremental())
continue;
gold_debug(DEBUG_INCREMENTAL,
"Applying incremental relocations for global symbol %s [%d]",
gsym->name(), i);
// Follow the linked list of input symbol table entries for this symbol.
// We don't bother to figure out whether the symbol table entry belongs
// to a changed or unchanged file because it's easier just to apply all
// the relocations -- although we might scribble over an area that has
// been reallocated, we do this before copying any new data into the
// output file.
unsigned int offset = isymtab.get_list_head(i);
while (offset > 0)
{
Incremental_global_symbol_reader<big_endian> sym_info =
this->inputs_reader().global_symbol_reader_at_offset(offset);
unsigned int r_base = sym_info.reloc_offset();
unsigned int r_count = sym_info.reloc_count();
// Apply each relocation for this symbol table entry.
for (unsigned int j = 0; j < r_count;
++j, r_base += incr_reloc_size)
{
unsigned int r_type = irelocs.get_r_type(r_base);
unsigned int r_shndx = irelocs.get_r_shndx(r_base);
Address r_offset = irelocs.get_r_offset(r_base);
Addend r_addend = irelocs.get_r_addend(r_base);
Output_section* os = this->output_section(r_shndx);
Address address = os->address();
off_t section_offset = os->offset();
size_t view_size = os->data_size();
unsigned char* const view = of->get_output_view(section_offset,
view_size);
gold_debug(DEBUG_INCREMENTAL,
" %08lx: %s + %d: type %d addend %ld",
(long)(section_offset + r_offset),
os->name(),
(int)r_offset,
r_type,
(long)r_addend);
target->apply_relocation(&relinfo, r_offset, r_type, r_addend,
gsym, view, address, view_size);
// FIXME: Do something more efficient if write_output_view
// ever becomes more than a no-op.
of->write_output_view(section_offset, view_size, view);
}
offset = sym_info.next_offset();
}
}
}
// Get a view of the main symbol table and the symbol string table.
template<int size, bool big_endian>
void
Sized_incremental_binary<size, big_endian>::get_symtab_view(
View* symtab_view,
unsigned int* nsyms,
elfcpp::Elf_strtab* strtab)
{
*symtab_view = this->view(this->main_symtab_loc_);
*nsyms = this->main_symtab_loc_.data_size / elfcpp::Elf_sizes<size>::sym_size;
View strtab_view(this->view(this->main_strtab_loc_));
*strtab = elfcpp::Elf_strtab(strtab_view.data(),
this->main_strtab_loc_.data_size);
}
namespace
{
// Create a Sized_incremental_binary object of the specified size and
// endianness. Fails if the target architecture is not supported.
template<int size, bool big_endian>
Incremental_binary*
make_sized_incremental_binary(Output_file* file,
const elfcpp::Ehdr<size, big_endian>& ehdr)
{
Target* target = select_target(NULL, 0, // XXX
ehdr.get_e_machine(), size, big_endian,
ehdr.get_ei_osabi(),
ehdr.get_ei_abiversion());
if (target == NULL)
{
explain_no_incremental(_("unsupported ELF machine number %d"),
ehdr.get_e_machine());
return NULL;
}
if (!parameters->target_valid())
set_parameters_target(target);
else if (target != &parameters->target())
gold_error(_("%s: incompatible target"), file->filename());
return new Sized_incremental_binary<size, big_endian>(file, ehdr, target);
}
} // End of anonymous namespace.
// Create an Incremental_binary object for FILE. Returns NULL is this is not
// possible, e.g. FILE is not an ELF file or has an unsupported target. FILE
// should be opened.
Incremental_binary*
open_incremental_binary(Output_file* file)
{
off_t filesize = file->filesize();
int want = elfcpp::Elf_recognizer::max_header_size;
if (filesize < want)
want = filesize;
const unsigned char* p = file->get_input_view(0, want);
if (!elfcpp::Elf_recognizer::is_elf_file(p, want))
{
explain_no_incremental(_("output is not an ELF file."));
return NULL;
}
int size = 0;
bool big_endian = false;
std::string error;
if (!elfcpp::Elf_recognizer::is_valid_header(p, want, &size, &big_endian,
&error))
{
explain_no_incremental(error.c_str());
return NULL;
}
Incremental_binary* result = NULL;
if (size == 32)
{
if (big_endian)
{
#ifdef HAVE_TARGET_32_BIG
result = make_sized_incremental_binary<32, true>(
file, elfcpp::Ehdr<32, true>(p));
#else
explain_no_incremental(_("unsupported file: 32-bit, big-endian"));
#endif
}
else
{
#ifdef HAVE_TARGET_32_LITTLE
result = make_sized_incremental_binary<32, false>(
file, elfcpp::Ehdr<32, false>(p));
#else
explain_no_incremental(_("unsupported file: 32-bit, little-endian"));
#endif
}
}
else if (size == 64)
{
if (big_endian)
{
#ifdef HAVE_TARGET_64_BIG
result = make_sized_incremental_binary<64, true>(
file, elfcpp::Ehdr<64, true>(p));
#else
explain_no_incremental(_("unsupported file: 64-bit, big-endian"));
#endif
}
else
{
#ifdef HAVE_TARGET_64_LITTLE
result = make_sized_incremental_binary<64, false>(
file, elfcpp::Ehdr<64, false>(p));
#else
explain_no_incremental(_("unsupported file: 64-bit, little-endian"));
#endif
}
}
else
gold_unreachable();
return result;
}
// Class Incremental_inputs.
// Add the command line to the string table, setting
// command_line_key_. In incremental builds, the command line is
// stored in .gnu_incremental_inputs so that the next linker run can
// check if the command line options didn't change.
void
Incremental_inputs::report_command_line(int argc, const char* const* argv)
{
// Always store 'gold' as argv[0] to avoid a full relink if the user used a
// different path to the linker.
std::string args("gold");
// Copied from collect_argv in main.cc.
for (int i = 1; i < argc; ++i)
{
// Adding/removing these options should not result in a full relink.
if (strcmp(argv[i], "--incremental") == 0
|| strcmp(argv[i], "--incremental-full") == 0
|| strcmp(argv[i], "--incremental-update") == 0
|| strcmp(argv[i], "--incremental-changed") == 0
|| strcmp(argv[i], "--incremental-unchanged") == 0
|| strcmp(argv[i], "--incremental-unknown") == 0
|| strcmp(argv[i], "--incremental-startup-unchanged") == 0
|| is_prefix_of("--incremental-base=", argv[i])
|| is_prefix_of("--incremental-patch=", argv[i])
|| is_prefix_of("--debug=", argv[i]))
continue;
if (strcmp(argv[i], "--incremental-base") == 0
|| strcmp(argv[i], "--incremental-patch") == 0
|| strcmp(argv[i], "--debug") == 0)
{
// When these options are used without the '=', skip the
// following parameter as well.
++i;
continue;
}
args.append(" '");
// Now append argv[i], but with all single-quotes escaped
const char* argpos = argv[i];
while (1)
{
const int len = strcspn(argpos, "'");
args.append(argpos, len);
if (argpos[len] == '\0')
break;
args.append("'\"'\"'");
argpos += len + 1;
}
args.append("'");
}
this->command_line_ = args;
this->strtab_->add(this->command_line_.c_str(), false,
&this->command_line_key_);
}
// Record the input archive file ARCHIVE. This is called by the
// Add_archive_symbols task before determining which archive members
// to include. We create the Incremental_archive_entry here and
// attach it to the Archive, but we do not add it to the list of
// input objects until report_archive_end is called.
void
Incremental_inputs::report_archive_begin(Library_base* arch,
unsigned int arg_serial,
Script_info* script_info)
{
Stringpool::Key filename_key;
Timespec mtime = arch->get_mtime();
// For a file loaded from a script, don't record its argument serial number.
if (script_info != NULL)
arg_serial = 0;
this->strtab_->add(arch->filename().c_str(), false, &filename_key);
Incremental_archive_entry* entry =
new Incremental_archive_entry(filename_key, arg_serial, mtime);
arch->set_incremental_info(entry);
if (script_info != NULL)
{
Incremental_script_entry* script_entry = script_info->incremental_info();
gold_assert(script_entry != NULL);
script_entry->add_object(entry);
}
}
// Visitor class for processing the unused global symbols in a library.
// An instance of this class is passed to the library's
// for_all_unused_symbols() iterator, which will call the visit()
// function for each global symbol defined in each unused library
// member. We add those symbol names to the incremental info for the
// library.
class Unused_symbol_visitor : public Library_base::Symbol_visitor_base
{
public:
Unused_symbol_visitor(Incremental_archive_entry* entry, Stringpool* strtab)
: entry_(entry), strtab_(strtab)
{ }
void
visit(const char* sym)
{
Stringpool::Key symbol_key;
this->strtab_->add(sym, true, &symbol_key);
this->entry_->add_unused_global_symbol(symbol_key);
}
private:
Incremental_archive_entry* entry_;
Stringpool* strtab_;
};
// Finish recording the input archive file ARCHIVE. This is called by the
// Add_archive_symbols task after determining which archive members
// to include.
void
Incremental_inputs::report_archive_end(Library_base* arch)
{
Incremental_archive_entry* entry = arch->incremental_info();
gold_assert(entry != NULL);
this->inputs_.push_back(entry);
// Collect unused global symbols.
Unused_symbol_visitor v(entry, this->strtab_);
arch->for_all_unused_symbols(&v);
}
// Record the input object file OBJ. If ARCH is not NULL, attach
// the object file to the archive. This is called by the
// Add_symbols task after finding out the type of the file.
void
Incremental_inputs::report_object(Object* obj, unsigned int arg_serial,
Library_base* arch, Script_info* script_info)
{
Stringpool::Key filename_key;
Timespec mtime = obj->get_mtime();
// For a file loaded from a script, don't record its argument serial number.
if (script_info != NULL)
arg_serial = 0;
this->strtab_->add(obj->name().c_str(), false, &filename_key);
Incremental_input_entry* input_entry;
this->current_object_ = obj;
if (!obj->is_dynamic())
{
this->current_object_entry_ =
new Incremental_object_entry(filename_key, obj, arg_serial, mtime);
input_entry = this->current_object_entry_;
if (arch != NULL)
{
Incremental_archive_entry* arch_entry = arch->incremental_info();
gold_assert(arch_entry != NULL);
arch_entry->add_object(this->current_object_entry_);
}
}
else
{
this->current_object_entry_ = NULL;
Stringpool::Key soname_key;
Dynobj* dynobj = obj->dynobj();
gold_assert(dynobj != NULL);
this->strtab_->add(dynobj->soname(), false, &soname_key);
input_entry = new Incremental_dynobj_entry(filename_key, soname_key, obj,
arg_serial, mtime);
}
if (obj->is_in_system_directory())
input_entry->set_is_in_system_directory();
if (obj->as_needed())
input_entry->set_as_needed();
this->inputs_.push_back(input_entry);
if (script_info != NULL)
{
Incremental_script_entry* script_entry = script_info->incremental_info();
gold_assert(script_entry != NULL);
script_entry->add_object(input_entry);
}
}
// Record an input section SHNDX from object file OBJ.
void
Incremental_inputs::report_input_section(Object* obj, unsigned int shndx,
const char* name, off_t sh_size)
{
Stringpool::Key key = 0;
if (name != NULL)
this->strtab_->add(name, true, &key);
gold_assert(obj == this->current_object_);
gold_assert(this->current_object_entry_ != NULL);
this->current_object_entry_->add_input_section(shndx, key, sh_size);
}
// Record a kept COMDAT group belonging to object file OBJ.
void
Incremental_inputs::report_comdat_group(Object* obj, const char* name)
{
Stringpool::Key key = 0;
if (name != NULL)
this->strtab_->add(name, true, &key);
gold_assert(obj == this->current_object_);
gold_assert(this->current_object_entry_ != NULL);
this->current_object_entry_->add_comdat_group(key);
}
// Record that the input argument INPUT is a script SCRIPT. This is
// called by read_script after parsing the script and reading the list
// of inputs added by this script.
void
Incremental_inputs::report_script(Script_info* script,
unsigned int arg_serial,
Timespec mtime)
{
Stringpool::Key filename_key;
this->strtab_->add(script->filename().c_str(), false, &filename_key);
Incremental_script_entry* entry =
new Incremental_script_entry(filename_key, arg_serial, script, mtime);
this->inputs_.push_back(entry);
script->set_incremental_info(entry);
}
// Finalize the incremental link information. Called from
// Layout::finalize.
void
Incremental_inputs::finalize()
{
// Finalize the string table.
this->strtab_->set_string_offsets();
}
// Create the .gnu_incremental_inputs, _symtab, and _relocs input sections.
void
Incremental_inputs::create_data_sections(Symbol_table* symtab)
{
int reloc_align = 4;
switch (parameters->size_and_endianness())
{
#ifdef HAVE_TARGET_32_LITTLE
case Parameters::TARGET_32_LITTLE:
this->inputs_section_ =
new Output_section_incremental_inputs<32, false>(this, symtab);
reloc_align = 4;
break;
#endif
#ifdef HAVE_TARGET_32_BIG
case Parameters::TARGET_32_BIG:
this->inputs_section_ =
new Output_section_incremental_inputs<32, true>(this, symtab);
reloc_align = 4;
break;
#endif
#ifdef HAVE_TARGET_64_LITTLE
case Parameters::TARGET_64_LITTLE:
this->inputs_section_ =
new Output_section_incremental_inputs<64, false>(this, symtab);
reloc_align = 8;
break;
#endif
#ifdef HAVE_TARGET_64_BIG
case Parameters::TARGET_64_BIG:
this->inputs_section_ =
new Output_section_incremental_inputs<64, true>(this, symtab);
reloc_align = 8;
break;
#endif
default:
gold_unreachable();
}
this->symtab_section_ = new Output_data_space(4, "** incremental_symtab");
this->relocs_section_ = new Output_data_space(reloc_align,
"** incremental_relocs");
this->got_plt_section_ = new Output_data_space(4, "** incremental_got_plt");
}
// Return the sh_entsize value for the .gnu_incremental_relocs section.
unsigned int
Incremental_inputs::relocs_entsize() const
{
return 8 + 2 * parameters->target().get_size() / 8;
}
// Class Output_section_incremental_inputs.
// Finalize the offsets for each input section and supplemental info block,
// and set the final data size of the incremental output sections.
template<int size, bool big_endian>
void
Output_section_incremental_inputs<size, big_endian>::set_final_data_size()
{
const Incremental_inputs* inputs = this->inputs_;
// Offset of each input entry.
unsigned int input_offset = this->header_size;
// Offset of each supplemental info block.
unsigned int file_index = 0;
unsigned int info_offset = this->header_size;
info_offset += this->input_entry_size * inputs->input_file_count();
// Count each input file and its supplemental information block.
for (Incremental_inputs::Input_list::const_iterator p =
inputs->input_files().begin();
p != inputs->input_files().end();
++p)
{
// Set the index and offset of the input file entry.
(*p)->set_offset(file_index, input_offset);
++file_index;
input_offset += this->input_entry_size;
// Set the offset of the supplemental info block.
switch ((*p)->type())
{
case INCREMENTAL_INPUT_SCRIPT:
{
Incremental_script_entry *entry = (*p)->script_entry();
gold_assert(entry != NULL);
(*p)->set_info_offset(info_offset);
// Object count.
info_offset += 4;
// Each member.
info_offset += (entry->get_object_count() * 4);
}
break;
case INCREMENTAL_INPUT_OBJECT:
case INCREMENTAL_INPUT_ARCHIVE_MEMBER:
{
Incremental_object_entry* entry = (*p)->object_entry();
gold_assert(entry != NULL);
(*p)->set_info_offset(info_offset);
// Input section count, global symbol count, local symbol offset,
// local symbol count, first dynamic reloc, dynamic reloc count,
// comdat group count.
info_offset += this->object_info_size;
// Each input section.
info_offset += (entry->get_input_section_count()
* this->input_section_entry_size);
// Each global symbol.
const Object::Symbols* syms = entry->object()->get_global_symbols();
info_offset += syms->size() * this->global_sym_entry_size;
// Each comdat group.
info_offset += entry->get_comdat_group_count() * 4;
}
break;
case INCREMENTAL_INPUT_SHARED_LIBRARY:
{
Incremental_dynobj_entry* entry = (*p)->dynobj_entry();
gold_assert(entry != NULL);
(*p)->set_info_offset(info_offset);
// Global symbol count, soname index.
info_offset += 8;
// Each global symbol.
const Object::Symbols* syms = entry->object()->get_global_symbols();
gold_assert(syms != NULL);
unsigned int nsyms = syms->size();
unsigned int nsyms_out = 0;
for (unsigned int i = 0; i < nsyms; ++i)
{
const Symbol* sym = (*syms)[i];
if (sym == NULL)
continue;
if (sym->is_forwarder())
sym = this->symtab_->resolve_forwards(sym);
if (sym->symtab_index() != -1U)
++nsyms_out;
}
info_offset += nsyms_out * 4;
}
break;
case INCREMENTAL_INPUT_ARCHIVE:
{
Incremental_archive_entry* entry = (*p)->archive_entry();
gold_assert(entry != NULL);
(*p)->set_info_offset(info_offset);
// Member count + unused global symbol count.
info_offset += 8;
// Each member.
info_offset += (entry->get_member_count() * 4);
// Each global symbol.
info_offset += (entry->get_unused_global_symbol_count() * 4);
}
break;
default:
gold_unreachable();
}
// Pad so each supplemental info block begins at an 8-byte boundary.
if (info_offset & 4)
info_offset += 4;
}
this->set_data_size(info_offset);
// Set the size of the .gnu_incremental_symtab section.
inputs->symtab_section()->set_current_data_size(this->symtab_->output_count()
* sizeof(unsigned int));
// Set the size of the .gnu_incremental_relocs section.
inputs->relocs_section()->set_current_data_size(inputs->get_reloc_count()
* this->incr_reloc_size);
// Set the size of the .gnu_incremental_got_plt section.
Sized_target<size, big_endian>* target =
parameters->sized_target<size, big_endian>();
unsigned int got_count = target->got_entry_count();
unsigned int plt_count = target->plt_entry_count();
unsigned int got_plt_size = 8; // GOT entry count, PLT entry count.
got_plt_size = (got_plt_size + got_count + 3) & ~3; // GOT type array.
got_plt_size += got_count * 8 + plt_count * 4; // GOT array, PLT array.
inputs->got_plt_section()->set_current_data_size(got_plt_size);
}
// Write the contents of the .gnu_incremental_inputs and
// .gnu_incremental_symtab sections.
template<int size, bool big_endian>
void
Output_section_incremental_inputs<size, big_endian>::do_write(Output_file* of)
{
const Incremental_inputs* inputs = this->inputs_;
Stringpool* strtab = inputs->get_stringpool();
// Get a view into the .gnu_incremental_inputs section.
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;
// Get a view into the .gnu_incremental_symtab section.
const off_t symtab_off = inputs->symtab_section()->offset();
const off_t symtab_size = inputs->symtab_section()->data_size();
unsigned char* const symtab_view = of->get_output_view(symtab_off,
symtab_size);
// Allocate an array of linked list heads for the .gnu_incremental_symtab
// section. Each element corresponds to a global symbol in the output
// symbol table, and points to the head of the linked list that threads
// through the object file input entries. The value of each element
// is the section-relative offset to a global symbol entry in a
// supplemental information block.
unsigned int global_sym_count = this->symtab_->output_count();
unsigned int* global_syms = new unsigned int[global_sym_count];
memset(global_syms, 0, global_sym_count * sizeof(unsigned int));
// Write the section header.
Stringpool::Key command_line_key = inputs->command_line_key();
pov = this->write_header(pov, inputs->input_file_count(),
strtab->get_offset_from_key(command_line_key));
// Write the list of input files.
pov = this->write_input_files(oview, pov, strtab);
// Write the supplemental information blocks for each input file.
pov = this->write_info_blocks(oview, pov, strtab, global_syms,
global_sym_count);
gold_assert(pov - oview == oview_size);
// Write the .gnu_incremental_symtab section.
gold_assert(static_cast<off_t>(global_sym_count) * 4 == symtab_size);
this->write_symtab(symtab_view, global_syms, global_sym_count);
delete[] global_syms;
// Write the .gnu_incremental_got_plt section.
const off_t got_plt_off = inputs->got_plt_section()->offset();
const off_t got_plt_size = inputs->got_plt_section()->data_size();
unsigned char* const got_plt_view = of->get_output_view(got_plt_off,
got_plt_size);
this->write_got_plt(got_plt_view, got_plt_size);
of->write_output_view(off, oview_size, oview);
of->write_output_view(symtab_off, symtab_size, symtab_view);
of->write_output_view(got_plt_off, got_plt_size, got_plt_view);
}
// Write the section header: version, input file count, offset of command line
// in the string table, and 4 bytes of padding.
template<int size, bool big_endian>
unsigned char*
Output_section_incremental_inputs<size, big_endian>::write_header(
unsigned char* pov,
unsigned int input_file_count,
section_offset_type command_line_offset)
{
Swap32::writeval(pov, INCREMENTAL_LINK_VERSION);
Swap32::writeval(pov + 4, input_file_count);
Swap32::writeval(pov + 8, command_line_offset);
Swap32::writeval(pov + 12, 0);
gold_assert(this->header_size == 16);
return pov + this->header_size;
}
// Write the input file entries.
template<int size, bool big_endian>
unsigned char*
Output_section_incremental_inputs<size, big_endian>::write_input_files(
unsigned char* oview,
unsigned char* pov,
Stringpool* strtab)
{
const Incremental_inputs* inputs = this->inputs_;
for (Incremental_inputs::Input_list::const_iterator p =
inputs->input_files().begin();
p != inputs->input_files().end();
++p)
{
gold_assert(static_cast<unsigned int>(pov - oview) == (*p)->get_offset());
section_offset_type filename_offset =
strtab->get_offset_from_key((*p)->get_filename_key());
const Timespec& mtime = (*p)->get_mtime();
unsigned int flags = (*p)->type();
if ((*p)->is_in_system_directory())
flags |= INCREMENTAL_INPUT_IN_SYSTEM_DIR;
if ((*p)->as_needed())
flags |= INCREMENTAL_INPUT_AS_NEEDED;
Swap32::writeval(pov, filename_offset);
Swap32::writeval(pov + 4, (*p)->get_info_offset());
Swap64::writeval(pov + 8, mtime.seconds);
Swap32::writeval(pov + 16, mtime.nanoseconds);
Swap16::writeval(pov + 20, flags);
Swap16::writeval(pov + 22, (*p)->arg_serial());
gold_assert(this->input_entry_size == 24);
pov += this->input_entry_size;
}
return pov;
}
// Write the supplemental information blocks.
template<int size, bool big_endian>
unsigned char*
Output_section_incremental_inputs<size, big_endian>::write_info_blocks(
unsigned char* oview,
unsigned char* pov,
Stringpool* strtab,
unsigned int* global_syms,
unsigned int global_sym_count)
{
const Incremental_inputs* inputs = this->inputs_;
unsigned int first_global_index = this->symtab_->first_global_index();
for (Incremental_inputs::Input_list::const_iterator p =
inputs->input_files().begin();
p != inputs->input_files().end();
++p)
{
switch ((*p)->type())
{
case INCREMENTAL_INPUT_SCRIPT:
{
gold_assert(static_cast<unsigned int>(pov - oview)
== (*p)->get_info_offset());
Incremental_script_entry* entry = (*p)->script_entry();
gold_assert(entry != NULL);
// Write the object count.
unsigned int nobjects = entry->get_object_count();
Swap32::writeval(pov, nobjects);
pov += 4;
// For each object, write the offset to its input file entry.
for (unsigned int i = 0; i < nobjects; ++i)
{
Incremental_input_entry* obj = entry->get_object(i);
Swap32::writeval(pov, obj->get_offset());
pov += 4;
}
}
break;
case INCREMENTAL_INPUT_OBJECT:
case INCREMENTAL_INPUT_ARCHIVE_MEMBER:
{
gold_assert(static_cast<unsigned int>(pov - oview)
== (*p)->get_info_offset());
Incremental_object_entry* entry = (*p)->object_entry();
gold_assert(entry != NULL);
const Object* obj = entry->object();
const Relobj* relobj = static_cast<const Relobj*>(obj);
const Object::Symbols* syms = obj->get_global_symbols();
// Write the input section count and global symbol count.
unsigned int nsections = entry->get_input_section_count();
unsigned int nsyms = syms->size();
off_t locals_offset = relobj->local_symbol_offset();
unsigned int nlocals = relobj->output_local_symbol_count();
unsigned int first_dynrel = relobj->first_dyn_reloc();
unsigned int ndynrel = relobj->dyn_reloc_count();
unsigned int ncomdat = entry->get_comdat_group_count();
Swap32::writeval(pov, nsections);
Swap32::writeval(pov + 4, nsyms);
Swap32::writeval(pov + 8, static_cast<unsigned int>(locals_offset));
Swap32::writeval(pov + 12, nlocals);
Swap32::writeval(pov + 16, first_dynrel);
Swap32::writeval(pov + 20, ndynrel);
Swap32::writeval(pov + 24, ncomdat);
Swap32::writeval(pov + 28, 0);
gold_assert(this->object_info_size == 32);
pov += this->object_info_size;
// Build a temporary array to map input section indexes
// from the original object file index to the index in the
// incremental info table.
unsigned int* index_map = new unsigned int[obj->shnum()];
memset(index_map, 0, obj->shnum() * sizeof(unsigned int));
// For each input section, write the name, output section index,
// offset within output section, and input section size.
for (unsigned int i = 0; i < nsections; i++)
{
unsigned int shndx = entry->get_input_section_index(i);
index_map[shndx] = i + 1;
Stringpool::Key key = entry->get_input_section_name_key(i);
off_t name_offset = 0;
if (key != 0)
name_offset = strtab->get_offset_from_key(key);
int out_shndx = 0;
off_t out_offset = 0;
off_t sh_size = 0;
Output_section* os = obj->output_section(shndx);
if (os != NULL)
{
out_shndx = os->out_shndx();
out_offset = obj->output_section_offset(shndx);
sh_size = entry->get_input_section_size(i);
}
Swap32::writeval(pov, name_offset);
Swap32::writeval(pov + 4, out_shndx);
Swap::writeval(pov + 8, out_offset);
Swap::writeval(pov + 8 + sizeof_addr, sh_size);
gold_assert(this->input_section_entry_size
== 8 + 2 * sizeof_addr);
pov += this->input_section_entry_size;
}
// For each global symbol, write its associated relocations,
// add it to the linked list of globals, then write the
// supplemental information: global symbol table index,
// input section index, linked list chain pointer, relocation
// count, and offset to the relocations.
for (unsigned int i = 0; i < nsyms; i++)
{
const Symbol* sym = (*syms)[i];
if (sym->is_forwarder())
sym = this->symtab_->resolve_forwards(sym);
unsigned int shndx = 0;
if (sym->source() != Symbol::FROM_OBJECT)
{
// The symbol was defined by the linker (e.g., common).
// We mark these symbols with a special SHNDX of -1,
// but exclude linker-predefined symbols and symbols
// copied from shared objects.
if (!sym->is_predefined()
&& !sym->is_copied_from_dynobj())
shndx = -1U;
}
else if (sym->object() == obj && sym->is_defined())
{
bool is_ordinary;
unsigned int orig_shndx = sym->shndx(&is_ordinary);
if (is_ordinary)
shndx = index_map[orig_shndx];
else
shndx = 1;
}
unsigned int symtab_index = sym->symtab_index();
unsigned int chain = 0;
unsigned int first_reloc = 0;
unsigned int nrelocs = obj->get_incremental_reloc_count(i);
if (nrelocs > 0)
{
gold_assert(symtab_index != -1U
&& (symtab_index - first_global_index
< global_sym_count));
first_reloc = obj->get_incremental_reloc_base(i);
chain = global_syms[symtab_index - first_global_index];
global_syms[symtab_index - first_global_index] =
pov - oview;
}
Swap32::writeval(pov, symtab_index);
Swap32::writeval(pov + 4, shndx);
Swap32::writeval(pov + 8, chain);
Swap32::writeval(pov + 12, nrelocs);
Swap32::writeval(pov + 16,
first_reloc * (8 + 2 * sizeof_addr));
gold_assert(this->global_sym_entry_size == 20);
pov += this->global_sym_entry_size;
}
// For each kept COMDAT group, write the group signature.
for (unsigned int i = 0; i < ncomdat; i++)
{
Stringpool::Key key = entry->get_comdat_signature_key(i);
off_t name_offset = 0;
if (key != 0)
name_offset = strtab->get_offset_from_key(key);
Swap32::writeval(pov, name_offset);
pov += 4;
}
delete[] index_map;
}
break;
case INCREMENTAL_INPUT_SHARED_LIBRARY:
{
gold_assert(static_cast<unsigned int>(pov - oview)
== (*p)->get_info_offset());
Incremental_dynobj_entry* entry = (*p)->dynobj_entry();
gold_assert(entry != NULL);
Object* obj = entry->object();
Dynobj* dynobj = obj->dynobj();
gold_assert(dynobj != NULL);
const Object::Symbols* syms = obj->get_global_symbols();
// Write the soname string table index.
section_offset_type soname_offset =
strtab->get_offset_from_key(entry->get_soname_key());
Swap32::writeval(pov, soname_offset);
pov += 4;
// Skip the global symbol count for now.
unsigned char* orig_pov = pov;
pov += 4;
// For each global symbol, write the global symbol table index.
unsigned int nsyms = syms->size();
unsigned int nsyms_out = 0;
for (unsigned int i = 0; i < nsyms; i++)
{
const Symbol* sym = (*syms)[i];
if (sym == NULL)
continue;
if (sym->is_forwarder())
sym = this->symtab_->resolve_forwards(sym);
if (sym->symtab_index() == -1U)
continue;
unsigned int flags = 0;
// If the symbol has hidden or internal visibility, we
// mark it as defined in the shared object so we don't
// try to resolve it during an incremental update.
if (sym->visibility() == elfcpp::STV_HIDDEN
|| sym->visibility() == elfcpp::STV_INTERNAL)
flags = INCREMENTAL_SHLIB_SYM_DEF;
else if (sym->source() == Symbol::FROM_OBJECT
&& sym->object() == obj
&& sym->is_defined())
flags = INCREMENTAL_SHLIB_SYM_DEF;
else if (sym->is_copied_from_dynobj()
&& this->symtab_->get_copy_source(sym) == dynobj)
flags = INCREMENTAL_SHLIB_SYM_COPY;
flags <<= INCREMENTAL_SHLIB_SYM_FLAGS_SHIFT;
Swap32::writeval(pov, sym->symtab_index() | flags);
pov += 4;
++nsyms_out;
}
// Now write the global symbol count.
Swap32::writeval(orig_pov, nsyms_out);
}
break;
case INCREMENTAL_INPUT_ARCHIVE:
{
gold_assert(static_cast<unsigned int>(pov - oview)
== (*p)->get_info_offset());
Incremental_archive_entry* entry = (*p)->archive_entry();
gold_assert(entry != NULL);
// Write the member count and unused global symbol count.
unsigned int nmembers = entry->get_member_count();
unsigned int nsyms = entry->get_unused_global_symbol_count();
Swap32::writeval(pov, nmembers);
Swap32::writeval(pov + 4, nsyms);
pov += 8;
// For each member, write the offset to its input file entry.
for (unsigned int i = 0; i < nmembers; ++i)
{
Incremental_object_entry* member = entry->get_member(i);
Swap32::writeval(pov, member->get_offset());
pov += 4;
}
// For each global symbol, write the name offset.
for (unsigned int i = 0; i < nsyms; ++i)
{
Stringpool::Key key = entry->get_unused_global_symbol(i);
Swap32::writeval(pov, strtab->get_offset_from_key(key));
pov += 4;
}
}
break;
default:
gold_unreachable();
}
// Pad the info block to a multiple of 8 bytes.
if (static_cast<unsigned int>(pov - oview) & 4)
{
Swap32::writeval(pov, 0);
pov += 4;
}
}
return pov;
}
// Write the contents of the .gnu_incremental_symtab section.
template<int size, bool big_endian>
void
Output_section_incremental_inputs<size, big_endian>::write_symtab(
unsigned char* pov,
unsigned int* global_syms,
unsigned int global_sym_count)
{
for (unsigned int i = 0; i < global_sym_count; ++i)
{
Swap32::writeval(pov, global_syms[i]);
pov += 4;
}
}
// This struct holds the view information needed to write the
// .gnu_incremental_got_plt section.
struct Got_plt_view_info
{
// Start of the GOT type array in the output view.
unsigned char* got_type_p;
// Start of the GOT descriptor array in the output view.
unsigned char* got_desc_p;
// Start of the PLT descriptor array in the output view.
unsigned char* plt_desc_p;
// Number of GOT entries.
unsigned int got_count;
// Number of PLT entries.
unsigned int plt_count;
// Offset of the first non-reserved PLT entry (this is a target-dependent value).
unsigned int first_plt_entry_offset;
// Size of a PLT entry (this is a target-dependent value).
unsigned int plt_entry_size;
// Size of a GOT entry (this is a target-dependent value).
unsigned int got_entry_size;
// Symbol index to write in the GOT descriptor array. For global symbols,
// this is the global symbol table index; for local symbols, it is the
// local symbol table index.
unsigned int sym_index;
// Input file index to write in the GOT descriptor array. For global
// symbols, this is 0; for local symbols, it is the index of the input
// file entry in the .gnu_incremental_inputs section.
unsigned int input_index;
};
// Functor class for processing a GOT offset list for local symbols.
// Writes the GOT type and symbol index into the GOT type and descriptor
// arrays in the output section.
template<int size, bool big_endian>
class Local_got_offset_visitor : public Got_offset_list::Visitor
{
public:
Local_got_offset_visitor(struct Got_plt_view_info& info)
: info_(info)
{ }
void
visit(unsigned int got_type, unsigned int got_offset)
{
unsigned int got_index = got_offset / this->info_.got_entry_size;
gold_assert(got_index < this->info_.got_count);
// We can only handle GOT entry types in the range 0..0x7e
// because we use a byte array to store them, and we use the
// high bit to flag a local symbol.
gold_assert(got_type < 0x7f);
this->info_.got_type_p[got_index] = got_type | 0x80;
unsigned char* pov = this->info_.got_desc_p + got_index * 8;
elfcpp::Swap<32, big_endian>::writeval(pov, this->info_.sym_index);
elfcpp::Swap<32, big_endian>::writeval(pov + 4, this->info_.input_index);
}
private:
struct Got_plt_view_info& info_;
};
// Functor class for processing a GOT offset list. Writes the GOT type
// and symbol index into the GOT type and descriptor arrays in the output
// section.
template<int size, bool big_endian>
class Global_got_offset_visitor : public Got_offset_list::Visitor
{
public:
Global_got_offset_visitor(struct Got_plt_view_info& info)
: info_(info)
{ }
void
visit(unsigned int got_type, unsigned int got_offset)
{
unsigned int got_index = got_offset / this->info_.got_entry_size;
gold_assert(got_index < this->info_.got_count);
// We can only handle GOT entry types in the range 0..0x7e
// because we use a byte array to store them, and we use the
// high bit to flag a local symbol.
gold_assert(got_type < 0x7f);
this->info_.got_type_p[got_index] = got_type;
unsigned char* pov = this->info_.got_desc_p + got_index * 8;
elfcpp::Swap<32, big_endian>::writeval(pov, this->info_.sym_index);
elfcpp::Swap<32, big_endian>::writeval(pov + 4, 0);
}
private:
struct Got_plt_view_info& info_;
};
// Functor class for processing the global symbol table. Processes the
// GOT offset list for the symbol, and writes the symbol table index
// into the PLT descriptor array in the output section.
template<int size, bool big_endian>
class Global_symbol_visitor_got_plt
{
public:
Global_symbol_visitor_got_plt(struct Got_plt_view_info& info)
: info_(info)
{ }
void
operator()(const Sized_symbol<size>* sym)
{
typedef Global_got_offset_visitor<size, big_endian> Got_visitor;
const Got_offset_list* got_offsets = sym->got_offset_list();
if (got_offsets != NULL)
{
this->info_.sym_index = sym->symtab_index();
this->info_.input_index = 0;
Got_visitor v(this->info_);
got_offsets->for_all_got_offsets(&v);
}
if (sym->has_plt_offset())
{
unsigned int plt_index =
((sym->plt_offset() - this->info_.first_plt_entry_offset)
/ this->info_.plt_entry_size);
gold_assert(plt_index < this->info_.plt_count);
unsigned char* pov = this->info_.plt_desc_p + plt_index * 4;
elfcpp::Swap<32, big_endian>::writeval(pov, sym->symtab_index());
}
}
private:
struct Got_plt_view_info& info_;
};
// Write the contents of the .gnu_incremental_got_plt section.
template<int size, bool big_endian>
void
Output_section_incremental_inputs<size, big_endian>::write_got_plt(
unsigned char* pov,
off_t view_size)
{
Sized_target<size, big_endian>* target =
parameters->sized_target<size, big_endian>();
// Set up the view information for the functors.
struct Got_plt_view_info view_info;
view_info.got_count = target->got_entry_count();
view_info.plt_count = target->plt_entry_count();
view_info.first_plt_entry_offset = target->first_plt_entry_offset();
view_info.plt_entry_size = target->plt_entry_size();
view_info.got_entry_size = target->got_entry_size();
view_info.got_type_p = pov + 8;
view_info.got_desc_p = (view_info.got_type_p
+ ((view_info.got_count + 3) & ~3));
view_info.plt_desc_p = view_info.got_desc_p + view_info.got_count * 8;
gold_assert(pov + view_size ==
view_info.plt_desc_p + view_info.plt_count * 4);
// Write the section header.
Swap32::writeval(pov, view_info.got_count);
Swap32::writeval(pov + 4, view_info.plt_count);
// Initialize the GOT type array to 0xff (reserved).
memset(view_info.got_type_p, 0xff, view_info.got_count);
// Write the incremental GOT descriptors for local symbols.
typedef Local_got_offset_visitor<size, big_endian> Got_visitor;
for (Incremental_inputs::Input_list::const_iterator p =
this->inputs_->input_files().begin();
p != this->inputs_->input_files().end();
++p)
{
if ((*p)->type() != INCREMENTAL_INPUT_OBJECT
&& (*p)->type() != INCREMENTAL_INPUT_ARCHIVE_MEMBER)
continue;
Incremental_object_entry* entry = (*p)->object_entry();
gold_assert(entry != NULL);
const Object* obj = entry->object();
gold_assert(obj != NULL);
view_info.input_index = (*p)->get_file_index();
Got_visitor v(view_info);
obj->for_all_local_got_entries(&v);
}
// Write the incremental GOT and PLT descriptors for global symbols.
typedef Global_symbol_visitor_got_plt<size, big_endian> Symbol_visitor;
symtab_->for_all_symbols<size, Symbol_visitor>(Symbol_visitor(view_info));
}
// Class Sized_relobj_incr. Most of these methods are not used for
// Incremental objects, but are required to be implemented by the
// base class Object.
template<int size, bool big_endian>
Sized_relobj_incr<size, big_endian>::Sized_relobj_incr(
const std::string& name,
Sized_incremental_binary<size, big_endian>* ibase,
unsigned int input_file_index)
: Sized_relobj<size, big_endian>(name, NULL), ibase_(ibase),
input_file_index_(input_file_index),
input_reader_(ibase->inputs_reader().input_file(input_file_index)),
local_symbol_count_(0), output_local_dynsym_count_(0),
local_symbol_index_(0), local_symbol_offset_(0), local_dynsym_offset_(0),
symbols_(), defined_count_(0), incr_reloc_offset_(-1U),
incr_reloc_count_(0), incr_reloc_output_index_(0), incr_relocs_(NULL),
local_symbols_()
{
if (this->input_reader_.is_in_system_directory())
this->set_is_in_system_directory();
const unsigned int shnum = this->input_reader_.get_input_section_count() + 1;
this->set_shnum(shnum);
ibase->set_input_object(input_file_index, this);
}
// Read the symbols.
template<int size, bool big_endian>
void
Sized_relobj_incr<size, big_endian>::do_read_symbols(Read_symbols_data*)
{
gold_unreachable();
}
// Lay out the input sections.
template<int size, bool big_endian>
void
Sized_relobj_incr<size, big_endian>::do_layout(
Symbol_table*,
Layout* layout,
Read_symbols_data*)
{
const unsigned int shnum = this->shnum();
Incremental_inputs* incremental_inputs = layout->incremental_inputs();
gold_assert(incremental_inputs != NULL);
Output_sections& out_sections(this->output_sections());
out_sections.resize(shnum);
this->section_offsets().resize(shnum);
// Keep track of .debug_info and .debug_types sections.
std::vector<unsigned int> debug_info_sections;
std::vector<unsigned int> debug_types_sections;
for (unsigned int i = 1; i < shnum; i++)
{
typename Input_entry_reader::Input_section_info sect =
this->input_reader_.get_input_section(i - 1);
// Add the section to the incremental inputs layout.
incremental_inputs->report_input_section(this, i, sect.name,
sect.sh_size);
if (sect.output_shndx == 0 || sect.sh_offset == -1)
continue;
Output_section* os = this->ibase_->output_section(sect.output_shndx);
gold_assert(os != NULL);
out_sections[i] = os;
this->section_offsets()[i] = static_cast<Address>(sect.sh_offset);
// When generating a .gdb_index section, we do additional
// processing of .debug_info and .debug_types sections after all
// the other sections.
if (parameters->options().gdb_index())
{
const char* name = os->name();
if (strcmp(name, ".debug_info") == 0)
debug_info_sections.push_back(i);
else if (strcmp(name, ".debug_types") == 0)
debug_types_sections.push_back(i);
}
}
// Process the COMDAT groups.
unsigned int ncomdat = this->input_reader_.get_comdat_group_count();
for (unsigned int i = 0; i < ncomdat; i++)
{
const char* signature = this->input_reader_.get_comdat_group_signature(i);
if (signature == NULL || signature[0] == '\0')
this->error(_("COMDAT group has no signature"));
bool keep = layout->find_or_add_kept_section(signature, this, i, true,
true, NULL);
if (keep)
incremental_inputs->report_comdat_group(this, signature);
else
this->error(_("COMDAT group %s included twice in incremental link"),
signature);
}
// When building a .gdb_index section, scan the .debug_info and
// .debug_types sections.
for (std::vector<unsigned int>::const_iterator p
= debug_info_sections.begin();
p != debug_info_sections.end();
++p)
{
unsigned int i = *p;
layout->add_to_gdb_index(false, this, NULL, 0, i, 0, 0);
}
for (std::vector<unsigned int>::const_iterator p
= debug_types_sections.begin();
p != debug_types_sections.end();
++p)
{
unsigned int i = *p;
layout->add_to_gdb_index(true, this, 0, 0, i, 0, 0);
}
}
// Layout sections whose layout was deferred while waiting for
// input files from a plugin.
template<int size, bool big_endian>
void
Sized_relobj_incr<size, big_endian>::do_layout_deferred_sections(Layout*)
{
}
// Add the symbols to the symbol table.
template<int size, bool big_endian>
void
Sized_relobj_incr<size, big_endian>::do_add_symbols(
Symbol_table* symtab,
Read_symbols_data*,
Layout*)
{
const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
unsigned char symbuf[sym_size];
elfcpp::Sym_write<size, big_endian> osym(symbuf);
typedef typename elfcpp::Elf_types<size>::Elf_WXword Elf_size_type;
unsigned int nsyms = this->input_reader_.get_global_symbol_count();
this->symbols_.resize(nsyms);
Incremental_binary::View symtab_view(NULL);
unsigned int symtab_count;
elfcpp::Elf_strtab strtab(NULL, 0);
this->ibase_->get_symtab_view(&symtab_view, &symtab_count, &strtab);
Incremental_symtab_reader<big_endian> isymtab(this->ibase_->symtab_reader());
unsigned int isym_count = isymtab.symbol_count();
unsigned int first_global = symtab_count - isym_count;
const unsigned char* sym_p;
for (unsigned int i = 0; i < nsyms; ++i)
{
Incremental_global_symbol_reader<big_endian> info =
this->input_reader_.get_global_symbol_reader(i);
unsigned int output_symndx = info.output_symndx();
sym_p = symtab_view.data() + output_symndx * sym_size;
elfcpp::Sym<size, big_endian> gsym(sym_p);
const char* name;
if (!strtab.get_c_string(gsym.get_st_name(), &name))
name = "";
typename elfcpp::Elf_types<size>::Elf_Addr v = gsym.get_st_value();
unsigned int shndx = gsym.get_st_shndx();
elfcpp::STB st_bind = gsym.get_st_bind();
elfcpp::STT st_type = gsym.get_st_type();
// Local hidden symbols start out as globals, but get converted to
// to local during output.
if (st_bind == elfcpp::STB_LOCAL)
st_bind = elfcpp::STB_GLOBAL;
unsigned int input_shndx = info.shndx();
if (input_shndx == 0 || input_shndx == -1U)
{
shndx = elfcpp::SHN_UNDEF;
v = 0;
}
else if (shndx != elfcpp::SHN_ABS)
{
// Find the input section and calculate the section-relative value.
gold_assert(shndx != elfcpp::SHN_UNDEF);
Output_section* os = this->ibase_->output_section(shndx);
gold_assert(os != NULL && os->has_fixed_layout());
typename Input_entry_reader::Input_section_info sect =
this->input_reader_.get_input_section(input_shndx - 1);
gold_assert(sect.output_shndx == shndx);
if (st_type != elfcpp::STT_TLS)
v -= os->address();
v -= sect.sh_offset;
shndx = input_shndx;
}
osym.put_st_name(0);
osym.put_st_value(v);
osym.put_st_size(gsym.get_st_size());
osym.put_st_info(st_bind, st_type);
osym.put_st_other(gsym.get_st_other());
osym.put_st_shndx(shndx);
elfcpp::Sym<size, big_endian> sym(symbuf);
Symbol* res = symtab->add_from_incrobj(this, name, NULL, &sym);
if (shndx != elfcpp::SHN_UNDEF)
++this->defined_count_;
// If this is a linker-defined symbol that hasn't yet been defined,
// define it now.
if (input_shndx == -1U && !res->is_defined())
{
shndx = gsym.get_st_shndx();
v = gsym.get_st_value();
Elf_size_type symsize = gsym.get_st_size();
if (shndx == elfcpp::SHN_ABS)
{
symtab->define_as_constant(name, NULL,
Symbol_table::INCREMENTAL_BASE,
v, symsize, st_type, st_bind,
gsym.get_st_visibility(), 0,
false, false);
}
else
{
Output_section* os = this->ibase_->output_section(shndx);
gold_assert(os != NULL && os->has_fixed_layout());
v -= os->address();
if (symsize > 0)
os->reserve(v, symsize);
symtab->define_in_output_data(name, NULL,
Symbol_table::INCREMENTAL_BASE,
os, v, symsize, st_type, st_bind,
gsym.get_st_visibility(), 0,
false, false);
}
}
this->symbols_[i] = res;
this->ibase_->add_global_symbol(output_symndx - first_global, res);
}
}
// Return TRUE if we should include this object from an archive library.
template<int size, bool big_endian>
Archive::Should_include
Sized_relobj_incr<size, big_endian>::do_should_include_member(
Symbol_table*,
Layout*,
Read_symbols_data*,
std::string*)
{
gold_unreachable();
}
// Iterate over global symbols, calling a visitor class V for each.
template<int size, bool big_endian>
void
Sized_relobj_incr<size, big_endian>::do_for_all_global_symbols(
Read_symbols_data*,
Library_base::Symbol_visitor_base*)
{
// This routine is not used for incremental objects.
}
// Get the size of a section.
template<int size, bool big_endian>
uint64_t
Sized_relobj_incr<size, big_endian>::do_section_size(unsigned int)
{
gold_unreachable();
}
// Get the name of a section. This returns the name of the output
// section, because we don't usually track the names of the input
// sections.
template<int size, bool big_endian>
std::string
Sized_relobj_incr<size, big_endian>::do_section_name(unsigned int shndx) const
{
const Output_sections& out_sections(this->output_sections());
const Output_section* os = out_sections[shndx];
if (os == NULL)
return NULL;
return os->name();
}
// Return a view of the contents of a section.
template<int size, bool big_endian>
const unsigned char*
Sized_relobj_incr<size, big_endian>::do_section_contents(
unsigned int shndx,
section_size_type* plen,
bool)
{
Output_sections& out_sections(this->output_sections());
Output_section* os = out_sections[shndx];
gold_assert(os != NULL);
off_t section_offset = os->offset();
typename Input_entry_reader::Input_section_info sect =
this->input_reader_.get_input_section(shndx - 1);
section_offset += sect.sh_offset;
*plen = sect.sh_size;
return this->ibase_->view(section_offset, sect.sh_size).data();
}
// Return section flags.
template<int size, bool big_endian>
uint64_t
Sized_relobj_incr<size, big_endian>::do_section_flags(unsigned int)
{
gold_unreachable();
}
// Return section entsize.
template<int size, bool big_endian>
uint64_t
Sized_relobj_incr<size, big_endian>::do_section_entsize(unsigned int)
{
gold_unreachable();
}
// Return section address.
template<int size, bool big_endian>
uint64_t
Sized_relobj_incr<size, big_endian>::do_section_address(unsigned int)
{
gold_unreachable();
}
// Return section type.
template<int size, bool big_endian>
unsigned int
Sized_relobj_incr<size, big_endian>::do_section_type(unsigned int)
{
gold_unreachable();
}
// Return the section link field.
template<int size, bool big_endian>
unsigned int
Sized_relobj_incr<size, big_endian>::do_section_link(unsigned int)
{
gold_unreachable();
}
// Return the section link field.
template<int size, bool big_endian>
unsigned int
Sized_relobj_incr<size, big_endian>::do_section_info(unsigned int)
{
gold_unreachable();
}
// Return the section alignment.
template<int size, bool big_endian>
uint64_t
Sized_relobj_incr<size, big_endian>::do_section_addralign(unsigned int)
{
gold_unreachable();
}
// Return the Xindex structure to use.
template<int size, bool big_endian>
Xindex*
Sized_relobj_incr<size, big_endian>::do_initialize_xindex()
{
gold_unreachable();
}
// Get symbol counts.
template<int size, bool big_endian>
void
Sized_relobj_incr<size, big_endian>::do_get_global_symbol_counts(
const Symbol_table*,
size_t* defined,
size_t* used) const
{
*defined = this->defined_count_;
size_t count = 0;
for (typename Symbols::const_iterator p = this->symbols_.begin();
p != this->symbols_.end();
++p)
if (*p != NULL
&& (*p)->source() == Symbol::FROM_OBJECT
&& (*p)->object() == this
&& (*p)->is_defined())
++count;
*used = count;
}
// Read the relocs.
template<int size, bool big_endian>
void
Sized_relobj_incr<size, big_endian>::do_read_relocs(Read_relocs_data*)
{
}
// Process the relocs to find list of referenced sections. Used only
// during garbage collection.
template<int size, bool big_endian>
void
Sized_relobj_incr<size, big_endian>::do_gc_process_relocs(Symbol_table*,
Layout*,
Read_relocs_data*)
{
gold_unreachable();
}
// Scan the relocs and adjust the symbol table.
template<int size, bool big_endian>
void
Sized_relobj_incr<size, big_endian>::do_scan_relocs(Symbol_table*,
Layout* layout,
Read_relocs_data*)
{
// Count the incremental relocations for this object.
unsigned int nsyms = this->input_reader_.get_global_symbol_count();
this->allocate_incremental_reloc_counts();
for (unsigned int i = 0; i < nsyms; i++)
{
Incremental_global_symbol_reader<big_endian> sym =
this->input_reader_.get_global_symbol_reader(i);
unsigned int reloc_count = sym.reloc_count();
if (reloc_count > 0 && this->incr_reloc_offset_ == -1U)
this->incr_reloc_offset_ = sym.reloc_offset();
this->incr_reloc_count_ += reloc_count;
for (unsigned int j = 0; j < reloc_count; j++)
this->count_incremental_reloc(i);
}
this->incr_reloc_output_index_ =
layout->incremental_inputs()->get_reloc_count();
this->finalize_incremental_relocs(layout, false);
// The incoming incremental relocations may not end up in the same
// location after the incremental update, because the incremental info
// is regenerated in each link. Because the new location may overlap
// with other data in the updated output file, we need to copy the
// relocations into a buffer so that we can still read them safely
// after we start writing updates to the output file.
if (this->incr_reloc_count_ > 0)
{
const Incremental_relocs_reader<size, big_endian>& relocs_reader =
this->ibase_->relocs_reader();
const unsigned int incr_reloc_size = relocs_reader.reloc_size;
unsigned int len = this->incr_reloc_count_ * incr_reloc_size;
this->incr_relocs_ = new unsigned char[len];
memcpy(this->incr_relocs_,
relocs_reader.data(this->incr_reloc_offset_),
len);
}
}
// Count the local symbols.
template<int size, bool big_endian>
void
Sized_relobj_incr<size, big_endian>::do_count_local_symbols(
Stringpool_template<char>* pool,
Stringpool_template<char>*)
{
const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
// Set the count of local symbols based on the incremental info.
unsigned int nlocals = this->input_reader_.get_local_symbol_count();
this->local_symbol_count_ = nlocals;
this->local_symbols_.reserve(nlocals);
// Get views of the base file's symbol table and string table.
Incremental_binary::View symtab_view(NULL);
unsigned int symtab_count;
elfcpp::Elf_strtab strtab(NULL, 0);
this->ibase_->get_symtab_view(&symtab_view, &symtab_count, &strtab);
// Read the local symbols from the base file's symbol table.
off_t off = this->input_reader_.get_local_symbol_offset();
const unsigned char* symp = symtab_view.data() + off;
for (unsigned int i = 0; i < nlocals; ++i, symp += sym_size)
{
elfcpp::Sym<size, big_endian> sym(symp);
const char* name;
if (!strtab.get_c_string(sym.get_st_name(), &name))
name = "";
gold_debug(DEBUG_INCREMENTAL, "Local symbol %d: %s", i, name);
name = pool->add(name, true, NULL);
this->local_symbols_.push_back(Local_symbol(name,
sym.get_st_value(),
sym.get_st_size(),
sym.get_st_shndx(),
sym.get_st_type(),
false));
}
}
// Finalize the local symbols.
template<int size, bool big_endian>
unsigned int
Sized_relobj_incr<size, big_endian>::do_finalize_local_symbols(
unsigned int index,
off_t off,
Symbol_table*)
{
this->local_symbol_index_ = index;
this->local_symbol_offset_ = off;
return index + this->local_symbol_count_;
}
// Set the offset where local dynamic symbol information will be stored.
template<int size, bool big_endian>
unsigned int
Sized_relobj_incr<size, big_endian>::do_set_local_dynsym_indexes(
unsigned int index)
{
// FIXME: set local dynsym indexes.
return index;
}
// Set the offset where local dynamic symbol information will be stored.
template<int size, bool big_endian>
unsigned int
Sized_relobj_incr<size, big_endian>::do_set_local_dynsym_offset(off_t)
{
return 0;
}
// Relocate the input sections and write out the local symbols.
// We don't actually do any relocation here. For unchanged input files,
// we reapply relocations only for symbols that have changed; that happens
// in Layout_task_runner::run(). We do need to rewrite the incremental
// relocations for this object.
template<int size, bool big_endian>
void
Sized_relobj_incr<size, big_endian>::do_relocate(const Symbol_table*,
const Layout* layout,
Output_file* of)
{
if (this->incr_reloc_count_ == 0)
return;
const unsigned int incr_reloc_size =
Incremental_relocs_reader<size, big_endian>::reloc_size;
// Get a view for the .gnu_incremental_relocs section.
Incremental_inputs* inputs = layout->incremental_inputs();
gold_assert(inputs != NULL);
const off_t relocs_off = inputs->relocs_section()->offset();
const off_t relocs_size = inputs->relocs_section()->data_size();
unsigned char* const view = of->get_output_view(relocs_off, relocs_size);
// Copy the relocations from the buffer.
off_t off = this->incr_reloc_output_index_ * incr_reloc_size;
unsigned int len = this->incr_reloc_count_ * incr_reloc_size;
memcpy(view + off, this->incr_relocs_, len);
// The output section table may have changed, so we need to map
// the old section index to the new section index for each relocation.
for (unsigned int i = 0; i < this->incr_reloc_count_; ++i)
{
unsigned char* pov = view + off + i * incr_reloc_size;
unsigned int shndx = elfcpp::Swap<32, big_endian>::readval(pov + 4);
Output_section* os = this->ibase_->output_section(shndx);
gold_assert(os != NULL);
shndx = os->out_shndx();
elfcpp::Swap<32, big_endian>::writeval(pov + 4, shndx);
}
of->write_output_view(off, len, view);
// Get views into the output file for the portions of the symbol table
// and the dynamic symbol table that we will be writing.
off_t symtab_off = layout->symtab_section()->offset();
off_t output_size = this->local_symbol_count_ * This::sym_size;
unsigned char* oview = NULL;
if (output_size > 0)
oview = of->get_output_view(symtab_off + this->local_symbol_offset_,
output_size);
off_t dyn_output_size = this->output_local_dynsym_count_ * sym_size;
unsigned char* dyn_oview = NULL;
if (dyn_output_size > 0)
dyn_oview = of->get_output_view(this->local_dynsym_offset_,
dyn_output_size);
// Write the local symbols.
unsigned char* ov = oview;
unsigned char* dyn_ov = dyn_oview;
const Stringpool* sympool = layout->sympool();
const Stringpool* dynpool = layout->dynpool();
Output_symtab_xindex* symtab_xindex = layout->symtab_xindex();
Output_symtab_xindex* dynsym_xindex = layout->dynsym_xindex();
for (unsigned int i = 0; i < this->local_symbol_count_; ++i)
{
Local_symbol& lsym(this->local_symbols_[i]);
bool is_ordinary;
unsigned int st_shndx = this->adjust_sym_shndx(i, lsym.st_shndx,
&is_ordinary);
if (is_ordinary)
{
Output_section* os = this->ibase_->output_section(st_shndx);
st_shndx = os->out_shndx();
if (st_shndx >= elfcpp::SHN_LORESERVE)
{
symtab_xindex->add(this->local_symbol_index_ + i, st_shndx);
if (lsym.needs_dynsym_entry)
dynsym_xindex->add(lsym.output_dynsym_index, st_shndx);
st_shndx = elfcpp::SHN_XINDEX;
}
}
// Write the symbol to the output symbol table.
{
elfcpp::Sym_write<size, big_endian> osym(ov);
osym.put_st_name(sympool->get_offset(lsym.name));
osym.put_st_value(lsym.st_value);
osym.put_st_size(lsym.st_size);
osym.put_st_info(elfcpp::STB_LOCAL,
static_cast<elfcpp::STT>(lsym.st_type));
osym.put_st_other(0);
osym.put_st_shndx(st_shndx);
ov += sym_size;
}
// Write the symbol to the output dynamic symbol table.
if (lsym.needs_dynsym_entry)
{
gold_assert(dyn_ov < dyn_oview + dyn_output_size);
elfcpp::Sym_write<size, big_endian> osym(dyn_ov);
osym.put_st_name(dynpool->get_offset(lsym.name));
osym.put_st_value(lsym.st_value);
osym.put_st_size(lsym.st_size);
osym.put_st_info(elfcpp::STB_LOCAL,
static_cast<elfcpp::STT>(lsym.st_type));
osym.put_st_other(0);
osym.put_st_shndx(st_shndx);
dyn_ov += sym_size;
}
}
if (output_size > 0)
{
gold_assert(ov - oview == output_size);
of->write_output_view(symtab_off + this->local_symbol_offset_,
output_size, oview);
}
if (dyn_output_size > 0)
{
gold_assert(dyn_ov - dyn_oview == dyn_output_size);
of->write_output_view(this->local_dynsym_offset_, dyn_output_size,
dyn_oview);
}
}
// Set the offset of a section.
template<int size, bool big_endian>
void
Sized_relobj_incr<size, big_endian>::do_set_section_offset(unsigned int,
uint64_t)
{
}
// Class Sized_incr_dynobj. Most of these methods are not used for
// Incremental objects, but are required to be implemented by the
// base class Object.
template<int size, bool big_endian>
Sized_incr_dynobj<size, big_endian>::Sized_incr_dynobj(
const std::string& name,
Sized_incremental_binary<size, big_endian>* ibase,
unsigned int input_file_index)
: Dynobj(name, NULL), ibase_(ibase),
input_file_index_(input_file_index),
input_reader_(ibase->inputs_reader().input_file(input_file_index)),
symbols_(), defined_count_(0)
{
if (this->input_reader_.is_in_system_directory())
this->set_is_in_system_directory();
if (this->input_reader_.as_needed())
this->set_as_needed();
this->set_soname_string(this->input_reader_.get_soname());
this->set_shnum(0);
}
// Read the symbols.
template<int size, bool big_endian>
void
Sized_incr_dynobj<size, big_endian>::do_read_symbols(Read_symbols_data*)
{
gold_unreachable();
}
// Lay out the input sections.
template<int size, bool big_endian>
void
Sized_incr_dynobj<size, big_endian>::do_layout(
Symbol_table*,
Layout*,
Read_symbols_data*)
{
}
// Add the symbols to the symbol table.
template<int size, bool big_endian>
void
Sized_incr_dynobj<size, big_endian>::do_add_symbols(
Symbol_table* symtab,
Read_symbols_data*,
Layout*)
{
const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
unsigned char symbuf[sym_size];
elfcpp::Sym_write<size, big_endian> osym(symbuf);
unsigned int nsyms = this->input_reader_.get_global_symbol_count();
this->symbols_.resize(nsyms);
Incremental_binary::View symtab_view(NULL);
unsigned int symtab_count;
elfcpp::Elf_strtab strtab(NULL, 0);
this->ibase_->get_symtab_view(&symtab_view, &symtab_count, &strtab);
Incremental_symtab_reader<big_endian> isymtab(this->ibase_->symtab_reader());
unsigned int isym_count = isymtab.symbol_count();
unsigned int first_global = symtab_count - isym_count;
// We keep a set of symbols that we have generated COPY relocations
// for, indexed by the symbol value. We do not need more than one
// COPY relocation per address.
typedef typename std::set<Address> Copied_symbols;
Copied_symbols copied_symbols;
const unsigned char* sym_p;
for (unsigned int i = 0; i < nsyms; ++i)
{
bool is_def;
bool is_copy;
unsigned int output_symndx =
this->input_reader_.get_output_symbol_index(i, &is_def, &is_copy);
sym_p = symtab_view.data() + output_symndx * sym_size;
elfcpp::Sym<size, big_endian> gsym(sym_p);
const char* name;
if (!strtab.get_c_string(gsym.get_st_name(), &name))
name = "";
Address v;
unsigned int shndx;
elfcpp::STB st_bind = gsym.get_st_bind();
elfcpp::STT st_type = gsym.get_st_type();
// Local hidden symbols start out as globals, but get converted to
// to local during output.
if (st_bind == elfcpp::STB_LOCAL)
st_bind = elfcpp::STB_GLOBAL;
if (!is_def)
{
shndx = elfcpp::SHN_UNDEF;
v = 0;
}
else
{
// For a symbol defined in a shared object, the section index
// is meaningless, as long as it's not SHN_UNDEF.
shndx = 1;
v = gsym.get_st_value();
++this->defined_count_;
}
osym.put_st_name(0);
osym.put_st_value(v);
osym.put_st_size(gsym.get_st_size());
osym.put_st_info(st_bind, st_type);
osym.put_st_other(gsym.get_st_other());
osym.put_st_shndx(shndx);
elfcpp::Sym<size, big_endian> sym(symbuf);
Sized_symbol<size>* res =
symtab->add_from_incrobj<size, big_endian>(this, name, NULL, &sym);
this->symbols_[i] = res;
this->ibase_->add_global_symbol(output_symndx - first_global,
this->symbols_[i]);
if (is_copy)
{
std::pair<typename Copied_symbols::iterator, bool> ins =
copied_symbols.insert(v);
if (ins.second)
{
unsigned int shndx = gsym.get_st_shndx();
Output_section* os = this->ibase_->output_section(shndx);
off_t offset = v - os->address();
this->ibase_->add_copy_reloc(this->symbols_[i], os, offset);
}
}
}
}
// Return TRUE if we should include this object from an archive library.
template<int size, bool big_endian>
Archive::Should_include
Sized_incr_dynobj<size, big_endian>::do_should_include_member(
Symbol_table*,
Layout*,
Read_symbols_data*,
std::string*)
{
gold_unreachable();
}
// Iterate over global symbols, calling a visitor class V for each.
template<int size, bool big_endian>
void
Sized_incr_dynobj<size, big_endian>::do_for_all_global_symbols(
Read_symbols_data*,
Library_base::Symbol_visitor_base*)
{
// This routine is not used for dynamic libraries.
}
// Iterate over local symbols, calling a visitor class V for each GOT offset
// associated with a local symbol.
template<int size, bool big_endian>
void
Sized_incr_dynobj<size, big_endian>::do_for_all_local_got_entries(
Got_offset_list::Visitor*) const
{
}
// Get the size of a section.
template<int size, bool big_endian>
uint64_t
Sized_incr_dynobj<size, big_endian>::do_section_size(unsigned int)
{
gold_unreachable();
}
// Get the name of a section.
template<int size, bool big_endian>
std::string
Sized_incr_dynobj<size, big_endian>::do_section_name(unsigned int) const
{
gold_unreachable();
}
// Return a view of the contents of a section.
template<int size, bool big_endian>
const unsigned char*
Sized_incr_dynobj<size, big_endian>::do_section_contents(
unsigned int,
section_size_type*,
bool)
{
gold_unreachable();
}
// Return section flags.
template<int size, bool big_endian>
uint64_t
Sized_incr_dynobj<size, big_endian>::do_section_flags(unsigned int)
{
gold_unreachable();
}
// Return section entsize.
template<int size, bool big_endian>
uint64_t
Sized_incr_dynobj<size, big_endian>::do_section_entsize(unsigned int)
{
gold_unreachable();
}
// Return section address.
template<int size, bool big_endian>
uint64_t
Sized_incr_dynobj<size, big_endian>::do_section_address(unsigned int)
{
gold_unreachable();
}
// Return section type.
template<int size, bool big_endian>
unsigned int
Sized_incr_dynobj<size, big_endian>::do_section_type(unsigned int)
{
gold_unreachable();
}
// Return the section link field.
template<int size, bool big_endian>
unsigned int
Sized_incr_dynobj<size, big_endian>::do_section_link(unsigned int)
{
gold_unreachable();
}
// Return the section link field.
template<int size, bool big_endian>
unsigned int
Sized_incr_dynobj<size, big_endian>::do_section_info(unsigned int)
{
gold_unreachable();
}
// Return the section alignment.
template<int size, bool big_endian>
uint64_t
Sized_incr_dynobj<size, big_endian>::do_section_addralign(unsigned int)
{
gold_unreachable();
}
// Return the Xindex structure to use.
template<int size, bool big_endian>
Xindex*
Sized_incr_dynobj<size, big_endian>::do_initialize_xindex()
{
gold_unreachable();
}
// Get symbol counts.
template<int size, bool big_endian>
void
Sized_incr_dynobj<size, big_endian>::do_get_global_symbol_counts(
const Symbol_table*,
size_t* defined,
size_t* used) const
{
*defined = this->defined_count_;
size_t count = 0;
for (typename Symbols::const_iterator p = this->symbols_.begin();
p != this->symbols_.end();
++p)
if (*p != NULL
&& (*p)->source() == Symbol::FROM_OBJECT
&& (*p)->object() == this
&& (*p)->is_defined()
&& (*p)->dynsym_index() != -1U)
++count;
*used = count;
}
// Allocate an incremental object of the appropriate size and endianness.
Object*
make_sized_incremental_object(
Incremental_binary* ibase,
unsigned int input_file_index,
Incremental_input_type input_type,
const Incremental_binary::Input_reader* input_reader)
{
Object* obj = NULL;
std::string name(input_reader->filename());
switch (parameters->size_and_endianness())
{
#ifdef HAVE_TARGET_32_LITTLE
case Parameters::TARGET_32_LITTLE:
{
Sized_incremental_binary<32, false>* sized_ibase =
static_cast<Sized_incremental_binary<32, false>*>(ibase);
if (input_type == INCREMENTAL_INPUT_SHARED_LIBRARY)
obj = new Sized_incr_dynobj<32, false>(name, sized_ibase,
input_file_index);
else
obj = new Sized_relobj_incr<32, false>(name, sized_ibase,
input_file_index);
}
break;
#endif
#ifdef HAVE_TARGET_32_BIG
case Parameters::TARGET_32_BIG:
{
Sized_incremental_binary<32, true>* sized_ibase =
static_cast<Sized_incremental_binary<32, true>*>(ibase);
if (input_type == INCREMENTAL_INPUT_SHARED_LIBRARY)
obj = new Sized_incr_dynobj<32, true>(name, sized_ibase,
input_file_index);
else
obj = new Sized_relobj_incr<32, true>(name, sized_ibase,
input_file_index);
}
break;
#endif
#ifdef HAVE_TARGET_64_LITTLE
case Parameters::TARGET_64_LITTLE:
{
Sized_incremental_binary<64, false>* sized_ibase =
static_cast<Sized_incremental_binary<64, false>*>(ibase);
if (input_type == INCREMENTAL_INPUT_SHARED_LIBRARY)
obj = new Sized_incr_dynobj<64, false>(name, sized_ibase,
input_file_index);
else
obj = new Sized_relobj_incr<64, false>(name, sized_ibase,
input_file_index);
}
break;
#endif
#ifdef HAVE_TARGET_64_BIG
case Parameters::TARGET_64_BIG:
{
Sized_incremental_binary<64, true>* sized_ibase =
static_cast<Sized_incremental_binary<64, true>*>(ibase);
if (input_type == INCREMENTAL_INPUT_SHARED_LIBRARY)
obj = new Sized_incr_dynobj<64, true>(name, sized_ibase,
input_file_index);
else
obj = new Sized_relobj_incr<64, true>(name, sized_ibase,
input_file_index);
}
break;
#endif
default:
gold_unreachable();
}
gold_assert(obj != NULL);
return obj;
}
// Copy the unused symbols from the incremental input info.
// We need to do this because we may be overwriting the incremental
// input info in the base file before we write the new incremental
// info.
void
Incremental_library::copy_unused_symbols()
{
unsigned int symcount = this->input_reader_->get_unused_symbol_count();
this->unused_symbols_.reserve(symcount);
for (unsigned int i = 0; i < symcount; ++i)
{
std::string name(this->input_reader_->get_unused_symbol(i));
this->unused_symbols_.push_back(name);
}
}
// Iterator for unused global symbols in the library.
void
Incremental_library::do_for_all_unused_symbols(Symbol_visitor_base* v) const
{
for (Symbol_list::const_iterator p = this->unused_symbols_.begin();
p != this->unused_symbols_.end();
++p)
v->visit(p->c_str());
}
// Instantiate the templates we need.
#ifdef HAVE_TARGET_32_LITTLE
template
class Sized_incremental_binary<32, false>;
template
class Sized_relobj_incr<32, false>;
template
class Sized_incr_dynobj<32, false>;
#endif
#ifdef HAVE_TARGET_32_BIG
template
class Sized_incremental_binary<32, true>;
template
class Sized_relobj_incr<32, true>;
template
class Sized_incr_dynobj<32, true>;
#endif
#ifdef HAVE_TARGET_64_LITTLE
template
class Sized_incremental_binary<64, false>;
template
class Sized_relobj_incr<64, false>;
template
class Sized_incr_dynobj<64, false>;
#endif
#ifdef HAVE_TARGET_64_BIG
template
class Sized_incremental_binary<64, true>;
template
class Sized_relobj_incr<64, true>;
template
class Sized_incr_dynobj<64, true>;
#endif
} // End namespace gold.