8dbe1edcd3
sections.
1883 lines
53 KiB
C++
1883 lines
53 KiB
C++
// reloc.cc -- relocate input files for gold.
|
|
|
|
// Copyright 2006, 2007, 2008, 2009, 2010, 2011 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 <algorithm>
|
|
|
|
#include "workqueue.h"
|
|
#include "layout.h"
|
|
#include "symtab.h"
|
|
#include "output.h"
|
|
#include "merge.h"
|
|
#include "object.h"
|
|
#include "target-reloc.h"
|
|
#include "reloc.h"
|
|
#include "icf.h"
|
|
#include "compressed_output.h"
|
|
#include "incremental.h"
|
|
|
|
namespace gold
|
|
{
|
|
|
|
// Read_relocs methods.
|
|
|
|
// These tasks just read the relocation information from the file.
|
|
// After reading it, the start another task to process the
|
|
// information. These tasks requires access to the file.
|
|
|
|
Task_token*
|
|
Read_relocs::is_runnable()
|
|
{
|
|
return this->object_->is_locked() ? this->object_->token() : NULL;
|
|
}
|
|
|
|
// Lock the file.
|
|
|
|
void
|
|
Read_relocs::locks(Task_locker* tl)
|
|
{
|
|
Task_token* token = this->object_->token();
|
|
if (token != NULL)
|
|
tl->add(this, token);
|
|
}
|
|
|
|
// Read the relocations and then start a Scan_relocs_task.
|
|
|
|
void
|
|
Read_relocs::run(Workqueue* workqueue)
|
|
{
|
|
Read_relocs_data* rd = new Read_relocs_data;
|
|
this->object_->read_relocs(rd);
|
|
this->object_->set_relocs_data(rd);
|
|
this->object_->release();
|
|
|
|
// If garbage collection or identical comdat folding is desired, we
|
|
// process the relocs first before scanning them. Scanning of relocs is
|
|
// done only after garbage or identical sections is identified.
|
|
if (parameters->options().gc_sections()
|
|
|| parameters->options().icf_enabled())
|
|
{
|
|
workqueue->queue_next(new Gc_process_relocs(this->symtab_,
|
|
this->layout_,
|
|
this->object_, rd,
|
|
this->this_blocker_,
|
|
this->next_blocker_));
|
|
}
|
|
else
|
|
{
|
|
workqueue->queue_next(new Scan_relocs(this->symtab_, this->layout_,
|
|
this->object_, rd,
|
|
this->this_blocker_,
|
|
this->next_blocker_));
|
|
}
|
|
}
|
|
|
|
// Return a debugging name for the task.
|
|
|
|
std::string
|
|
Read_relocs::get_name() const
|
|
{
|
|
return "Read_relocs " + this->object_->name();
|
|
}
|
|
|
|
// Gc_process_relocs methods.
|
|
|
|
Gc_process_relocs::~Gc_process_relocs()
|
|
{
|
|
if (this->this_blocker_ != NULL)
|
|
delete this->this_blocker_;
|
|
}
|
|
|
|
// These tasks process the relocations read by Read_relocs and
|
|
// determine which sections are referenced and which are garbage.
|
|
// This task is done only when --gc-sections is used. This is blocked
|
|
// by THIS_BLOCKER_. It unblocks NEXT_BLOCKER_.
|
|
|
|
Task_token*
|
|
Gc_process_relocs::is_runnable()
|
|
{
|
|
if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
|
|
return this->this_blocker_;
|
|
if (this->object_->is_locked())
|
|
return this->object_->token();
|
|
return NULL;
|
|
}
|
|
|
|
void
|
|
Gc_process_relocs::locks(Task_locker* tl)
|
|
{
|
|
tl->add(this, this->object_->token());
|
|
tl->add(this, this->next_blocker_);
|
|
}
|
|
|
|
void
|
|
Gc_process_relocs::run(Workqueue*)
|
|
{
|
|
this->object_->gc_process_relocs(this->symtab_, this->layout_, this->rd_);
|
|
this->object_->release();
|
|
}
|
|
|
|
// Return a debugging name for the task.
|
|
|
|
std::string
|
|
Gc_process_relocs::get_name() const
|
|
{
|
|
return "Gc_process_relocs " + this->object_->name();
|
|
}
|
|
|
|
// Scan_relocs methods.
|
|
|
|
Scan_relocs::~Scan_relocs()
|
|
{
|
|
if (this->this_blocker_ != NULL)
|
|
delete this->this_blocker_;
|
|
}
|
|
|
|
// These tasks scan the relocations read by Read_relocs and mark up
|
|
// the symbol table to indicate which relocations are required. We
|
|
// use a lock on the symbol table to keep them from interfering with
|
|
// each other.
|
|
|
|
Task_token*
|
|
Scan_relocs::is_runnable()
|
|
{
|
|
if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
|
|
return this->this_blocker_;
|
|
if (this->object_->is_locked())
|
|
return this->object_->token();
|
|
return NULL;
|
|
}
|
|
|
|
// Return the locks we hold: one on the file, one on the symbol table
|
|
// and one blocker.
|
|
|
|
void
|
|
Scan_relocs::locks(Task_locker* tl)
|
|
{
|
|
Task_token* token = this->object_->token();
|
|
if (token != NULL)
|
|
tl->add(this, token);
|
|
tl->add(this, this->next_blocker_);
|
|
}
|
|
|
|
// Scan the relocs.
|
|
|
|
void
|
|
Scan_relocs::run(Workqueue*)
|
|
{
|
|
this->object_->scan_relocs(this->symtab_, this->layout_, this->rd_);
|
|
delete this->rd_;
|
|
this->rd_ = NULL;
|
|
this->object_->release();
|
|
}
|
|
|
|
// Return a debugging name for the task.
|
|
|
|
std::string
|
|
Scan_relocs::get_name() const
|
|
{
|
|
return "Scan_relocs " + this->object_->name();
|
|
}
|
|
|
|
// Relocate_task methods.
|
|
|
|
// We may have to wait for the output sections to be written.
|
|
|
|
Task_token*
|
|
Relocate_task::is_runnable()
|
|
{
|
|
if (this->object_->relocs_must_follow_section_writes()
|
|
&& this->output_sections_blocker_->is_blocked())
|
|
return this->output_sections_blocker_;
|
|
|
|
if (this->object_->is_locked())
|
|
return this->object_->token();
|
|
|
|
return NULL;
|
|
}
|
|
|
|
// We want to lock the file while we run. We want to unblock
|
|
// INPUT_SECTIONS_BLOCKER and FINAL_BLOCKER when we are done.
|
|
// INPUT_SECTIONS_BLOCKER may be NULL.
|
|
|
|
void
|
|
Relocate_task::locks(Task_locker* tl)
|
|
{
|
|
if (this->input_sections_blocker_ != NULL)
|
|
tl->add(this, this->input_sections_blocker_);
|
|
tl->add(this, this->final_blocker_);
|
|
Task_token* token = this->object_->token();
|
|
if (token != NULL)
|
|
tl->add(this, token);
|
|
}
|
|
|
|
// Run the task.
|
|
|
|
void
|
|
Relocate_task::run(Workqueue*)
|
|
{
|
|
this->object_->relocate(this->symtab_, this->layout_, this->of_);
|
|
|
|
// This is normally the last thing we will do with an object, so
|
|
// uncache all views.
|
|
this->object_->clear_view_cache_marks();
|
|
|
|
this->object_->release();
|
|
}
|
|
|
|
// Return a debugging name for the task.
|
|
|
|
std::string
|
|
Relocate_task::get_name() const
|
|
{
|
|
return "Relocate_task " + this->object_->name();
|
|
}
|
|
|
|
// Read the relocs and local symbols from the object file and store
|
|
// the information in RD.
|
|
|
|
template<int size, bool big_endian>
|
|
void
|
|
Sized_relobj_file<size, big_endian>::do_read_relocs(Read_relocs_data* rd)
|
|
{
|
|
rd->relocs.clear();
|
|
|
|
unsigned int shnum = this->shnum();
|
|
if (shnum == 0)
|
|
return;
|
|
|
|
rd->relocs.reserve(shnum / 2);
|
|
|
|
const Output_sections& out_sections(this->output_sections());
|
|
const std::vector<Address>& out_offsets(this->section_offsets());
|
|
|
|
const unsigned char* pshdrs = this->get_view(this->elf_file_.shoff(),
|
|
shnum * This::shdr_size,
|
|
true, true);
|
|
// Skip the first, dummy, section.
|
|
const unsigned char* ps = pshdrs + This::shdr_size;
|
|
for (unsigned int i = 1; i < shnum; ++i, ps += This::shdr_size)
|
|
{
|
|
typename This::Shdr shdr(ps);
|
|
|
|
unsigned int sh_type = shdr.get_sh_type();
|
|
if (sh_type != elfcpp::SHT_REL && sh_type != elfcpp::SHT_RELA)
|
|
continue;
|
|
|
|
unsigned int shndx = this->adjust_shndx(shdr.get_sh_info());
|
|
if (shndx >= shnum)
|
|
{
|
|
this->error(_("relocation section %u has bad info %u"),
|
|
i, shndx);
|
|
continue;
|
|
}
|
|
|
|
Output_section* os = out_sections[shndx];
|
|
if (os == NULL)
|
|
continue;
|
|
|
|
// We are scanning relocations in order to fill out the GOT and
|
|
// PLT sections. Relocations for sections which are not
|
|
// allocated (typically debugging sections) should not add new
|
|
// GOT and PLT entries. So we skip them unless this is a
|
|
// relocatable link or we need to emit relocations. FIXME: What
|
|
// should we do if a linker script maps a section with SHF_ALLOC
|
|
// clear to a section with SHF_ALLOC set?
|
|
typename This::Shdr secshdr(pshdrs + shndx * This::shdr_size);
|
|
bool is_section_allocated = ((secshdr.get_sh_flags() & elfcpp::SHF_ALLOC)
|
|
!= 0);
|
|
if (!is_section_allocated
|
|
&& !parameters->options().relocatable()
|
|
&& !parameters->options().emit_relocs()
|
|
&& !parameters->incremental())
|
|
continue;
|
|
|
|
if (this->adjust_shndx(shdr.get_sh_link()) != this->symtab_shndx_)
|
|
{
|
|
this->error(_("relocation section %u uses unexpected "
|
|
"symbol table %u"),
|
|
i, this->adjust_shndx(shdr.get_sh_link()));
|
|
continue;
|
|
}
|
|
|
|
off_t sh_size = shdr.get_sh_size();
|
|
|
|
if (sh_size == 0)
|
|
continue;
|
|
|
|
unsigned int reloc_size;
|
|
if (sh_type == elfcpp::SHT_REL)
|
|
reloc_size = elfcpp::Elf_sizes<size>::rel_size;
|
|
else
|
|
reloc_size = elfcpp::Elf_sizes<size>::rela_size;
|
|
if (reloc_size != shdr.get_sh_entsize())
|
|
{
|
|
this->error(_("unexpected entsize for reloc section %u: %lu != %u"),
|
|
i, static_cast<unsigned long>(shdr.get_sh_entsize()),
|
|
reloc_size);
|
|
continue;
|
|
}
|
|
|
|
size_t reloc_count = sh_size / reloc_size;
|
|
if (static_cast<off_t>(reloc_count * reloc_size) != sh_size)
|
|
{
|
|
this->error(_("reloc section %u size %lu uneven"),
|
|
i, static_cast<unsigned long>(sh_size));
|
|
continue;
|
|
}
|
|
|
|
rd->relocs.push_back(Section_relocs());
|
|
Section_relocs& sr(rd->relocs.back());
|
|
sr.reloc_shndx = i;
|
|
sr.data_shndx = shndx;
|
|
sr.contents = this->get_lasting_view(shdr.get_sh_offset(), sh_size,
|
|
true, true);
|
|
sr.sh_type = sh_type;
|
|
sr.reloc_count = reloc_count;
|
|
sr.output_section = os;
|
|
sr.needs_special_offset_handling = out_offsets[shndx] == invalid_address;
|
|
sr.is_data_section_allocated = is_section_allocated;
|
|
}
|
|
|
|
// Read the local symbols.
|
|
gold_assert(this->symtab_shndx_ != -1U);
|
|
if (this->symtab_shndx_ == 0 || this->local_symbol_count_ == 0)
|
|
rd->local_symbols = NULL;
|
|
else
|
|
{
|
|
typename This::Shdr symtabshdr(pshdrs
|
|
+ this->symtab_shndx_ * This::shdr_size);
|
|
gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
|
|
const int sym_size = This::sym_size;
|
|
const unsigned int loccount = this->local_symbol_count_;
|
|
gold_assert(loccount == symtabshdr.get_sh_info());
|
|
off_t locsize = loccount * sym_size;
|
|
rd->local_symbols = this->get_lasting_view(symtabshdr.get_sh_offset(),
|
|
locsize, true, true);
|
|
}
|
|
}
|
|
|
|
// Process the relocs to generate mappings from source sections to referenced
|
|
// sections. This is used during garbage collection to determine garbage
|
|
// sections.
|
|
|
|
template<int size, bool big_endian>
|
|
void
|
|
Sized_relobj_file<size, big_endian>::do_gc_process_relocs(Symbol_table* symtab,
|
|
Layout* layout,
|
|
Read_relocs_data* rd)
|
|
{
|
|
Sized_target<size, big_endian>* target =
|
|
parameters->sized_target<size, big_endian>();
|
|
|
|
const unsigned char* local_symbols;
|
|
if (rd->local_symbols == NULL)
|
|
local_symbols = NULL;
|
|
else
|
|
local_symbols = rd->local_symbols->data();
|
|
|
|
for (Read_relocs_data::Relocs_list::iterator p = rd->relocs.begin();
|
|
p != rd->relocs.end();
|
|
++p)
|
|
{
|
|
if (!parameters->options().relocatable())
|
|
{
|
|
// As noted above, when not generating an object file, we
|
|
// only scan allocated sections. We may see a non-allocated
|
|
// section here if we are emitting relocs.
|
|
if (p->is_data_section_allocated)
|
|
target->gc_process_relocs(symtab, layout, this,
|
|
p->data_shndx, p->sh_type,
|
|
p->contents->data(), p->reloc_count,
|
|
p->output_section,
|
|
p->needs_special_offset_handling,
|
|
this->local_symbol_count_,
|
|
local_symbols);
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
// Scan the relocs and adjust the symbol table. This looks for
|
|
// relocations which require GOT/PLT/COPY relocations.
|
|
|
|
template<int size, bool big_endian>
|
|
void
|
|
Sized_relobj_file<size, big_endian>::do_scan_relocs(Symbol_table* symtab,
|
|
Layout* layout,
|
|
Read_relocs_data* rd)
|
|
{
|
|
Sized_target<size, big_endian>* target =
|
|
parameters->sized_target<size, big_endian>();
|
|
|
|
const unsigned char* local_symbols;
|
|
if (rd->local_symbols == NULL)
|
|
local_symbols = NULL;
|
|
else
|
|
local_symbols = rd->local_symbols->data();
|
|
|
|
// For incremental links, allocate the counters for incremental relocations.
|
|
if (layout->incremental_inputs() != NULL)
|
|
this->allocate_incremental_reloc_counts();
|
|
|
|
for (Read_relocs_data::Relocs_list::iterator p = rd->relocs.begin();
|
|
p != rd->relocs.end();
|
|
++p)
|
|
{
|
|
// When garbage collection is on, unreferenced sections are not included
|
|
// in the link that would have been included normally. This is known only
|
|
// after Read_relocs hence this check has to be done again.
|
|
if (parameters->options().gc_sections()
|
|
|| parameters->options().icf_enabled())
|
|
{
|
|
if (p->output_section == NULL)
|
|
continue;
|
|
}
|
|
if (!parameters->options().relocatable())
|
|
{
|
|
// As noted above, when not generating an object file, we
|
|
// only scan allocated sections. We may see a non-allocated
|
|
// section here if we are emitting relocs.
|
|
if (p->is_data_section_allocated)
|
|
target->scan_relocs(symtab, layout, this, p->data_shndx,
|
|
p->sh_type, p->contents->data(),
|
|
p->reloc_count, p->output_section,
|
|
p->needs_special_offset_handling,
|
|
this->local_symbol_count_,
|
|
local_symbols);
|
|
if (parameters->options().emit_relocs())
|
|
this->emit_relocs_scan(symtab, layout, local_symbols, p);
|
|
if (layout->incremental_inputs() != NULL)
|
|
this->incremental_relocs_scan(p);
|
|
}
|
|
else
|
|
{
|
|
Relocatable_relocs* rr = this->relocatable_relocs(p->reloc_shndx);
|
|
gold_assert(rr != NULL);
|
|
rr->set_reloc_count(p->reloc_count);
|
|
target->scan_relocatable_relocs(symtab, layout, this,
|
|
p->data_shndx, p->sh_type,
|
|
p->contents->data(),
|
|
p->reloc_count,
|
|
p->output_section,
|
|
p->needs_special_offset_handling,
|
|
this->local_symbol_count_,
|
|
local_symbols,
|
|
rr);
|
|
}
|
|
|
|
delete p->contents;
|
|
p->contents = NULL;
|
|
}
|
|
|
|
// For incremental links, finalize the allocation of relocations.
|
|
if (layout->incremental_inputs() != NULL)
|
|
this->finalize_incremental_relocs(layout, true);
|
|
|
|
if (rd->local_symbols != NULL)
|
|
{
|
|
delete rd->local_symbols;
|
|
rd->local_symbols = NULL;
|
|
}
|
|
}
|
|
|
|
// This is a strategy class we use when scanning for --emit-relocs.
|
|
|
|
template<int sh_type>
|
|
class Emit_relocs_strategy
|
|
{
|
|
public:
|
|
// A local non-section symbol.
|
|
inline Relocatable_relocs::Reloc_strategy
|
|
local_non_section_strategy(unsigned int, Relobj*, unsigned int)
|
|
{ return Relocatable_relocs::RELOC_COPY; }
|
|
|
|
// A local section symbol.
|
|
inline Relocatable_relocs::Reloc_strategy
|
|
local_section_strategy(unsigned int, Relobj*)
|
|
{
|
|
if (sh_type == elfcpp::SHT_RELA)
|
|
return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_RELA;
|
|
else
|
|
{
|
|
// The addend is stored in the section contents. Since this
|
|
// is not a relocatable link, we are going to apply the
|
|
// relocation contents to the section as usual. This means
|
|
// that we have no way to record the original addend. If the
|
|
// original addend is not zero, there is basically no way for
|
|
// the user to handle this correctly. Caveat emptor.
|
|
return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_0;
|
|
}
|
|
}
|
|
|
|
// A global symbol.
|
|
inline Relocatable_relocs::Reloc_strategy
|
|
global_strategy(unsigned int, Relobj*, unsigned int)
|
|
{ return Relocatable_relocs::RELOC_COPY; }
|
|
};
|
|
|
|
// Scan the input relocations for --emit-relocs.
|
|
|
|
template<int size, bool big_endian>
|
|
void
|
|
Sized_relobj_file<size, big_endian>::emit_relocs_scan(
|
|
Symbol_table* symtab,
|
|
Layout* layout,
|
|
const unsigned char* plocal_syms,
|
|
const Read_relocs_data::Relocs_list::iterator& p)
|
|
{
|
|
Relocatable_relocs* rr = this->relocatable_relocs(p->reloc_shndx);
|
|
gold_assert(rr != NULL);
|
|
rr->set_reloc_count(p->reloc_count);
|
|
|
|
if (p->sh_type == elfcpp::SHT_REL)
|
|
this->emit_relocs_scan_reltype<elfcpp::SHT_REL>(symtab, layout,
|
|
plocal_syms, p, rr);
|
|
else
|
|
{
|
|
gold_assert(p->sh_type == elfcpp::SHT_RELA);
|
|
this->emit_relocs_scan_reltype<elfcpp::SHT_RELA>(symtab, layout,
|
|
plocal_syms, p, rr);
|
|
}
|
|
}
|
|
|
|
// Scan the input relocation for --emit-relocs, templatized on the
|
|
// type of the relocation section.
|
|
|
|
template<int size, bool big_endian>
|
|
template<int sh_type>
|
|
void
|
|
Sized_relobj_file<size, big_endian>::emit_relocs_scan_reltype(
|
|
Symbol_table* symtab,
|
|
Layout* layout,
|
|
const unsigned char* plocal_syms,
|
|
const Read_relocs_data::Relocs_list::iterator& p,
|
|
Relocatable_relocs* rr)
|
|
{
|
|
scan_relocatable_relocs<size, big_endian, sh_type,
|
|
Emit_relocs_strategy<sh_type> >(
|
|
symtab,
|
|
layout,
|
|
this,
|
|
p->data_shndx,
|
|
p->contents->data(),
|
|
p->reloc_count,
|
|
p->output_section,
|
|
p->needs_special_offset_handling,
|
|
this->local_symbol_count_,
|
|
plocal_syms,
|
|
rr);
|
|
}
|
|
|
|
// Scan the input relocations for --incremental.
|
|
|
|
template<int size, bool big_endian>
|
|
void
|
|
Sized_relobj_file<size, big_endian>::incremental_relocs_scan(
|
|
const Read_relocs_data::Relocs_list::iterator& p)
|
|
{
|
|
if (p->sh_type == elfcpp::SHT_REL)
|
|
this->incremental_relocs_scan_reltype<elfcpp::SHT_REL>(p);
|
|
else
|
|
{
|
|
gold_assert(p->sh_type == elfcpp::SHT_RELA);
|
|
this->incremental_relocs_scan_reltype<elfcpp::SHT_RELA>(p);
|
|
}
|
|
}
|
|
|
|
// Scan the input relocation for --incremental, templatized on the
|
|
// type of the relocation section.
|
|
|
|
template<int size, bool big_endian>
|
|
template<int sh_type>
|
|
void
|
|
Sized_relobj_file<size, big_endian>::incremental_relocs_scan_reltype(
|
|
const Read_relocs_data::Relocs_list::iterator& p)
|
|
{
|
|
typedef typename Reloc_types<sh_type, size, big_endian>::Reloc Reltype;
|
|
const int reloc_size = Reloc_types<sh_type, size, big_endian>::reloc_size;
|
|
const unsigned char* prelocs = p->contents->data();
|
|
size_t reloc_count = p->reloc_count;
|
|
|
|
for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
|
|
{
|
|
Reltype reloc(prelocs);
|
|
|
|
if (p->needs_special_offset_handling
|
|
&& !p->output_section->is_input_address_mapped(this, p->data_shndx,
|
|
reloc.get_r_offset()))
|
|
continue;
|
|
|
|
typename elfcpp::Elf_types<size>::Elf_WXword r_info =
|
|
reloc.get_r_info();
|
|
const unsigned int r_sym = elfcpp::elf_r_sym<size>(r_info);
|
|
|
|
if (r_sym >= this->local_symbol_count_)
|
|
this->count_incremental_reloc(r_sym - this->local_symbol_count_);
|
|
}
|
|
}
|
|
|
|
// Relocate the input sections and write out the local symbols.
|
|
|
|
template<int size, bool big_endian>
|
|
void
|
|
Sized_relobj_file<size, big_endian>::do_relocate(const Symbol_table* symtab,
|
|
const Layout* layout,
|
|
Output_file* of)
|
|
{
|
|
unsigned int shnum = this->shnum();
|
|
|
|
// Read the section headers.
|
|
const unsigned char* pshdrs = this->get_view(this->elf_file_.shoff(),
|
|
shnum * This::shdr_size,
|
|
true, true);
|
|
|
|
Views views;
|
|
views.resize(shnum);
|
|
|
|
// Make two passes over the sections. The first one copies the
|
|
// section data to the output file. The second one applies
|
|
// relocations.
|
|
|
|
this->write_sections(pshdrs, of, &views);
|
|
|
|
// To speed up relocations, we set up hash tables for fast lookup of
|
|
// input offsets to output addresses.
|
|
this->initialize_input_to_output_maps();
|
|
|
|
// Apply relocations.
|
|
|
|
this->relocate_sections(symtab, layout, pshdrs, of, &views);
|
|
|
|
// After we've done the relocations, we release the hash tables,
|
|
// since we no longer need them.
|
|
this->free_input_to_output_maps();
|
|
|
|
// Write out the accumulated views.
|
|
for (unsigned int i = 1; i < shnum; ++i)
|
|
{
|
|
if (views[i].view != NULL)
|
|
{
|
|
if (!views[i].is_postprocessing_view)
|
|
{
|
|
if (views[i].is_input_output_view)
|
|
of->write_input_output_view(views[i].offset,
|
|
views[i].view_size,
|
|
views[i].view);
|
|
else
|
|
of->write_output_view(views[i].offset, views[i].view_size,
|
|
views[i].view);
|
|
}
|
|
}
|
|
}
|
|
|
|
// Write out the local symbols.
|
|
this->write_local_symbols(of, layout->sympool(), layout->dynpool(),
|
|
layout->symtab_xindex(), layout->dynsym_xindex(),
|
|
layout->symtab_section_offset());
|
|
}
|
|
|
|
// Sort a Read_multiple vector by file offset.
|
|
struct Read_multiple_compare
|
|
{
|
|
inline bool
|
|
operator()(const File_read::Read_multiple_entry& rme1,
|
|
const File_read::Read_multiple_entry& rme2) const
|
|
{ return rme1.file_offset < rme2.file_offset; }
|
|
};
|
|
|
|
// Write section data to the output file. PSHDRS points to the
|
|
// section headers. Record the views in *PVIEWS for use when
|
|
// relocating.
|
|
|
|
template<int size, bool big_endian>
|
|
void
|
|
Sized_relobj_file<size, big_endian>::write_sections(const unsigned char* pshdrs,
|
|
Output_file* of,
|
|
Views* pviews)
|
|
{
|
|
unsigned int shnum = this->shnum();
|
|
const Output_sections& out_sections(this->output_sections());
|
|
const std::vector<Address>& out_offsets(this->section_offsets());
|
|
|
|
File_read::Read_multiple rm;
|
|
bool is_sorted = true;
|
|
|
|
const unsigned char* p = pshdrs + This::shdr_size;
|
|
for (unsigned int i = 1; i < shnum; ++i, p += This::shdr_size)
|
|
{
|
|
View_size* pvs = &(*pviews)[i];
|
|
|
|
pvs->view = NULL;
|
|
|
|
const Output_section* os = out_sections[i];
|
|
if (os == NULL)
|
|
continue;
|
|
Address output_offset = out_offsets[i];
|
|
|
|
typename This::Shdr shdr(p);
|
|
|
|
if (shdr.get_sh_type() == elfcpp::SHT_NOBITS)
|
|
continue;
|
|
|
|
if ((parameters->options().relocatable()
|
|
|| parameters->options().emit_relocs())
|
|
&& (shdr.get_sh_type() == elfcpp::SHT_REL
|
|
|| shdr.get_sh_type() == elfcpp::SHT_RELA)
|
|
&& (shdr.get_sh_flags() & elfcpp::SHF_ALLOC) == 0)
|
|
{
|
|
// This is a reloc section in a relocatable link or when
|
|
// emitting relocs. We don't need to read the input file.
|
|
// The size and file offset are stored in the
|
|
// Relocatable_relocs structure.
|
|
Relocatable_relocs* rr = this->relocatable_relocs(i);
|
|
gold_assert(rr != NULL);
|
|
Output_data* posd = rr->output_data();
|
|
gold_assert(posd != NULL);
|
|
|
|
pvs->offset = posd->offset();
|
|
pvs->view_size = posd->data_size();
|
|
pvs->view = of->get_output_view(pvs->offset, pvs->view_size);
|
|
pvs->address = posd->address();
|
|
pvs->is_input_output_view = false;
|
|
pvs->is_postprocessing_view = false;
|
|
|
|
continue;
|
|
}
|
|
|
|
// In the normal case, this input section is simply mapped to
|
|
// the output section at offset OUTPUT_OFFSET.
|
|
|
|
// However, if OUTPUT_OFFSET == INVALID_ADDRESS, then input data is
|
|
// handled specially--e.g., a .eh_frame section. The relocation
|
|
// routines need to check for each reloc where it should be
|
|
// applied. For this case, we need an input/output view for the
|
|
// entire contents of the section in the output file. We don't
|
|
// want to copy the contents of the input section to the output
|
|
// section; the output section contents were already written,
|
|
// and we waited for them in Relocate_task::is_runnable because
|
|
// relocs_must_follow_section_writes is set for the object.
|
|
|
|
// Regardless of which of the above cases is true, we have to
|
|
// check requires_postprocessing of the output section. If that
|
|
// is false, then we work with views of the output file
|
|
// directly. If it is true, then we work with a separate
|
|
// buffer, and the output section is responsible for writing the
|
|
// final data to the output file.
|
|
|
|
off_t output_section_offset;
|
|
Address output_section_size;
|
|
if (!os->requires_postprocessing())
|
|
{
|
|
output_section_offset = os->offset();
|
|
output_section_size = convert_types<Address, off_t>(os->data_size());
|
|
}
|
|
else
|
|
{
|
|
output_section_offset = 0;
|
|
output_section_size =
|
|
convert_types<Address, off_t>(os->postprocessing_buffer_size());
|
|
}
|
|
|
|
off_t view_start;
|
|
section_size_type view_size;
|
|
bool must_decompress = false;
|
|
if (output_offset != invalid_address)
|
|
{
|
|
view_start = output_section_offset + output_offset;
|
|
view_size = convert_to_section_size_type(shdr.get_sh_size());
|
|
section_size_type uncompressed_size;
|
|
if (this->section_is_compressed(i, &uncompressed_size))
|
|
{
|
|
view_size = uncompressed_size;
|
|
must_decompress = true;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
view_start = output_section_offset;
|
|
view_size = convert_to_section_size_type(output_section_size);
|
|
}
|
|
|
|
if (view_size == 0)
|
|
continue;
|
|
|
|
gold_assert(output_offset == invalid_address
|
|
|| output_offset + view_size <= output_section_size);
|
|
|
|
unsigned char* view;
|
|
if (os->requires_postprocessing())
|
|
{
|
|
unsigned char* buffer = os->postprocessing_buffer();
|
|
view = buffer + view_start;
|
|
if (output_offset != invalid_address && !must_decompress)
|
|
{
|
|
off_t sh_offset = shdr.get_sh_offset();
|
|
if (!rm.empty() && rm.back().file_offset > sh_offset)
|
|
is_sorted = false;
|
|
rm.push_back(File_read::Read_multiple_entry(sh_offset,
|
|
view_size, view));
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if (output_offset == invalid_address)
|
|
view = of->get_input_output_view(view_start, view_size);
|
|
else
|
|
{
|
|
view = of->get_output_view(view_start, view_size);
|
|
if (!must_decompress)
|
|
{
|
|
off_t sh_offset = shdr.get_sh_offset();
|
|
if (!rm.empty() && rm.back().file_offset > sh_offset)
|
|
is_sorted = false;
|
|
rm.push_back(File_read::Read_multiple_entry(sh_offset,
|
|
view_size, view));
|
|
}
|
|
}
|
|
}
|
|
|
|
if (must_decompress)
|
|
{
|
|
// Read and decompress the section.
|
|
section_size_type len;
|
|
const unsigned char* p = this->section_contents(i, &len, false);
|
|
if (!decompress_input_section(p, len, view, view_size))
|
|
this->error(_("could not decompress section %s"),
|
|
this->section_name(i).c_str());
|
|
}
|
|
|
|
pvs->view = view;
|
|
pvs->address = os->address();
|
|
if (output_offset != invalid_address)
|
|
pvs->address += output_offset;
|
|
pvs->offset = view_start;
|
|
pvs->view_size = view_size;
|
|
pvs->is_input_output_view = output_offset == invalid_address;
|
|
pvs->is_postprocessing_view = os->requires_postprocessing();
|
|
}
|
|
|
|
// Actually read the data.
|
|
if (!rm.empty())
|
|
{
|
|
if (!is_sorted)
|
|
std::sort(rm.begin(), rm.end(), Read_multiple_compare());
|
|
this->read_multiple(rm);
|
|
}
|
|
}
|
|
|
|
// Relocate section data. VIEWS points to the section data as views
|
|
// in the output file.
|
|
|
|
template<int size, bool big_endian>
|
|
void
|
|
Sized_relobj_file<size, big_endian>::do_relocate_sections(
|
|
const Symbol_table* symtab,
|
|
const Layout* layout,
|
|
const unsigned char* pshdrs,
|
|
Output_file* of,
|
|
Views* pviews)
|
|
{
|
|
unsigned int shnum = this->shnum();
|
|
Sized_target<size, big_endian>* target =
|
|
parameters->sized_target<size, big_endian>();
|
|
|
|
const Output_sections& out_sections(this->output_sections());
|
|
const std::vector<Address>& out_offsets(this->section_offsets());
|
|
|
|
Relocate_info<size, big_endian> relinfo;
|
|
relinfo.symtab = symtab;
|
|
relinfo.layout = layout;
|
|
relinfo.object = this;
|
|
|
|
const unsigned char* p = pshdrs + This::shdr_size;
|
|
for (unsigned int i = 1; i < shnum; ++i, p += This::shdr_size)
|
|
{
|
|
typename This::Shdr shdr(p);
|
|
|
|
unsigned int sh_type = shdr.get_sh_type();
|
|
if (sh_type != elfcpp::SHT_REL && sh_type != elfcpp::SHT_RELA)
|
|
continue;
|
|
|
|
off_t sh_size = shdr.get_sh_size();
|
|
if (sh_size == 0)
|
|
continue;
|
|
|
|
unsigned int index = this->adjust_shndx(shdr.get_sh_info());
|
|
if (index >= this->shnum())
|
|
{
|
|
this->error(_("relocation section %u has bad info %u"),
|
|
i, index);
|
|
continue;
|
|
}
|
|
|
|
Output_section* os = out_sections[index];
|
|
if (os == NULL)
|
|
{
|
|
// This relocation section is against a section which we
|
|
// discarded.
|
|
continue;
|
|
}
|
|
Address output_offset = out_offsets[index];
|
|
|
|
gold_assert((*pviews)[index].view != NULL);
|
|
if (parameters->options().relocatable())
|
|
gold_assert((*pviews)[i].view != NULL);
|
|
|
|
if (this->adjust_shndx(shdr.get_sh_link()) != this->symtab_shndx_)
|
|
{
|
|
gold_error(_("relocation section %u uses unexpected "
|
|
"symbol table %u"),
|
|
i, this->adjust_shndx(shdr.get_sh_link()));
|
|
continue;
|
|
}
|
|
|
|
const unsigned char* prelocs = this->get_view(shdr.get_sh_offset(),
|
|
sh_size, true, false);
|
|
|
|
unsigned int reloc_size;
|
|
if (sh_type == elfcpp::SHT_REL)
|
|
reloc_size = elfcpp::Elf_sizes<size>::rel_size;
|
|
else
|
|
reloc_size = elfcpp::Elf_sizes<size>::rela_size;
|
|
|
|
if (reloc_size != shdr.get_sh_entsize())
|
|
{
|
|
gold_error(_("unexpected entsize for reloc section %u: %lu != %u"),
|
|
i, static_cast<unsigned long>(shdr.get_sh_entsize()),
|
|
reloc_size);
|
|
continue;
|
|
}
|
|
|
|
size_t reloc_count = sh_size / reloc_size;
|
|
if (static_cast<off_t>(reloc_count * reloc_size) != sh_size)
|
|
{
|
|
gold_error(_("reloc section %u size %lu uneven"),
|
|
i, static_cast<unsigned long>(sh_size));
|
|
continue;
|
|
}
|
|
|
|
gold_assert(output_offset != invalid_address
|
|
|| this->relocs_must_follow_section_writes());
|
|
|
|
relinfo.reloc_shndx = i;
|
|
relinfo.reloc_shdr = p;
|
|
relinfo.data_shndx = index;
|
|
relinfo.data_shdr = pshdrs + index * This::shdr_size;
|
|
unsigned char* view = (*pviews)[index].view;
|
|
Address address = (*pviews)[index].address;
|
|
section_size_type view_size = (*pviews)[index].view_size;
|
|
|
|
Reloc_symbol_changes* reloc_map = NULL;
|
|
if (this->uses_split_stack() && output_offset != invalid_address)
|
|
{
|
|
typename This::Shdr data_shdr(pshdrs + index * This::shdr_size);
|
|
if ((data_shdr.get_sh_flags() & elfcpp::SHF_EXECINSTR) != 0)
|
|
this->split_stack_adjust(symtab, pshdrs, sh_type, index,
|
|
prelocs, reloc_count, view, view_size,
|
|
&reloc_map);
|
|
}
|
|
|
|
if (!parameters->options().relocatable())
|
|
{
|
|
target->relocate_section(&relinfo, sh_type, prelocs, reloc_count, os,
|
|
output_offset == invalid_address,
|
|
view, address, view_size, reloc_map);
|
|
if (parameters->options().emit_relocs())
|
|
this->emit_relocs(&relinfo, i, sh_type, prelocs, reloc_count,
|
|
os, output_offset, view, address, view_size,
|
|
(*pviews)[i].view, (*pviews)[i].view_size);
|
|
if (parameters->incremental())
|
|
this->incremental_relocs_write(&relinfo, sh_type, prelocs,
|
|
reloc_count, os, output_offset, of);
|
|
}
|
|
else
|
|
{
|
|
Relocatable_relocs* rr = this->relocatable_relocs(i);
|
|
target->relocate_for_relocatable(&relinfo, sh_type, prelocs,
|
|
reloc_count, os, output_offset, rr,
|
|
view, address, view_size,
|
|
(*pviews)[i].view,
|
|
(*pviews)[i].view_size);
|
|
}
|
|
}
|
|
}
|
|
|
|
// Emit the relocs for --emit-relocs.
|
|
|
|
template<int size, bool big_endian>
|
|
void
|
|
Sized_relobj_file<size, big_endian>::emit_relocs(
|
|
const Relocate_info<size, big_endian>* relinfo,
|
|
unsigned int i,
|
|
unsigned int sh_type,
|
|
const unsigned char* prelocs,
|
|
size_t reloc_count,
|
|
Output_section* output_section,
|
|
typename elfcpp::Elf_types<size>::Elf_Addr offset_in_output_section,
|
|
unsigned char* view,
|
|
typename elfcpp::Elf_types<size>::Elf_Addr address,
|
|
section_size_type view_size,
|
|
unsigned char* reloc_view,
|
|
section_size_type reloc_view_size)
|
|
{
|
|
if (sh_type == elfcpp::SHT_REL)
|
|
this->emit_relocs_reltype<elfcpp::SHT_REL>(relinfo, i, prelocs,
|
|
reloc_count, output_section,
|
|
offset_in_output_section,
|
|
view, address, view_size,
|
|
reloc_view, reloc_view_size);
|
|
else
|
|
{
|
|
gold_assert(sh_type == elfcpp::SHT_RELA);
|
|
this->emit_relocs_reltype<elfcpp::SHT_RELA>(relinfo, i, prelocs,
|
|
reloc_count, output_section,
|
|
offset_in_output_section,
|
|
view, address, view_size,
|
|
reloc_view, reloc_view_size);
|
|
}
|
|
}
|
|
|
|
// Emit the relocs for --emit-relocs, templatized on the type of the
|
|
// relocation section.
|
|
|
|
template<int size, bool big_endian>
|
|
template<int sh_type>
|
|
void
|
|
Sized_relobj_file<size, big_endian>::emit_relocs_reltype(
|
|
const Relocate_info<size, big_endian>* relinfo,
|
|
unsigned int i,
|
|
const unsigned char* prelocs,
|
|
size_t reloc_count,
|
|
Output_section* output_section,
|
|
typename elfcpp::Elf_types<size>::Elf_Addr offset_in_output_section,
|
|
unsigned char* view,
|
|
typename elfcpp::Elf_types<size>::Elf_Addr address,
|
|
section_size_type view_size,
|
|
unsigned char* reloc_view,
|
|
section_size_type reloc_view_size)
|
|
{
|
|
const Relocatable_relocs* rr = this->relocatable_relocs(i);
|
|
relocate_for_relocatable<size, big_endian, sh_type>(
|
|
relinfo,
|
|
prelocs,
|
|
reloc_count,
|
|
output_section,
|
|
offset_in_output_section,
|
|
rr,
|
|
view,
|
|
address,
|
|
view_size,
|
|
reloc_view,
|
|
reloc_view_size);
|
|
}
|
|
|
|
// Write the incremental relocs.
|
|
|
|
template<int size, bool big_endian>
|
|
void
|
|
Sized_relobj_file<size, big_endian>::incremental_relocs_write(
|
|
const Relocate_info<size, big_endian>* relinfo,
|
|
unsigned int sh_type,
|
|
const unsigned char* prelocs,
|
|
size_t reloc_count,
|
|
Output_section* output_section,
|
|
Address output_offset,
|
|
Output_file* of)
|
|
{
|
|
if (sh_type == elfcpp::SHT_REL)
|
|
this->incremental_relocs_write_reltype<elfcpp::SHT_REL>(
|
|
relinfo,
|
|
prelocs,
|
|
reloc_count,
|
|
output_section,
|
|
output_offset,
|
|
of);
|
|
else
|
|
{
|
|
gold_assert(sh_type == elfcpp::SHT_RELA);
|
|
this->incremental_relocs_write_reltype<elfcpp::SHT_RELA>(
|
|
relinfo,
|
|
prelocs,
|
|
reloc_count,
|
|
output_section,
|
|
output_offset,
|
|
of);
|
|
}
|
|
}
|
|
|
|
// Write the incremental relocs, templatized on the type of the
|
|
// relocation section.
|
|
|
|
template<int size, bool big_endian>
|
|
template<int sh_type>
|
|
void
|
|
Sized_relobj_file<size, big_endian>::incremental_relocs_write_reltype(
|
|
const Relocate_info<size, big_endian>* relinfo,
|
|
const unsigned char* prelocs,
|
|
size_t reloc_count,
|
|
Output_section* output_section,
|
|
Address output_offset,
|
|
Output_file* of)
|
|
{
|
|
typedef typename Reloc_types<sh_type, size, big_endian>::Reloc Reloc;
|
|
const unsigned int reloc_size =
|
|
Reloc_types<sh_type, size, big_endian>::reloc_size;
|
|
const unsigned int sizeof_addr = size / 8;
|
|
const unsigned int incr_reloc_size =
|
|
Incremental_relocs_reader<size, big_endian>::reloc_size;
|
|
|
|
unsigned int out_shndx = output_section->out_shndx();
|
|
|
|
// Get a view for the .gnu_incremental_relocs section.
|
|
|
|
Incremental_inputs* inputs = relinfo->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);
|
|
|
|
for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
|
|
{
|
|
Reloc reloc(prelocs);
|
|
|
|
typename elfcpp::Elf_types<size>::Elf_WXword r_info = reloc.get_r_info();
|
|
const unsigned int r_sym = elfcpp::elf_r_sym<size>(r_info);
|
|
const unsigned int r_type = elfcpp::elf_r_type<size>(r_info);
|
|
|
|
if (r_sym < this->local_symbol_count_)
|
|
continue;
|
|
|
|
// Get the new offset--the location in the output section where
|
|
// this relocation should be applied.
|
|
|
|
Address offset = reloc.get_r_offset();
|
|
if (output_offset != invalid_address)
|
|
offset += output_offset;
|
|
else
|
|
{
|
|
section_offset_type sot_offset =
|
|
convert_types<section_offset_type, Address>(offset);
|
|
section_offset_type new_sot_offset =
|
|
output_section->output_offset(relinfo->object,
|
|
relinfo->data_shndx,
|
|
sot_offset);
|
|
gold_assert(new_sot_offset != -1);
|
|
offset += new_sot_offset;
|
|
}
|
|
|
|
// Get the addend.
|
|
typename elfcpp::Elf_types<size>::Elf_Swxword addend;
|
|
if (sh_type == elfcpp::SHT_RELA)
|
|
addend =
|
|
Reloc_types<sh_type, size, big_endian>::get_reloc_addend(&reloc);
|
|
else
|
|
{
|
|
// FIXME: Get the addend for SHT_REL.
|
|
addend = 0;
|
|
}
|
|
|
|
// Get the index of the output relocation.
|
|
|
|
unsigned int reloc_index =
|
|
this->next_incremental_reloc_index(r_sym - this->local_symbol_count_);
|
|
|
|
// Write the relocation.
|
|
|
|
unsigned char* pov = view + reloc_index * incr_reloc_size;
|
|
elfcpp::Swap<32, big_endian>::writeval(pov, r_type);
|
|
elfcpp::Swap<32, big_endian>::writeval(pov + 4, out_shndx);
|
|
elfcpp::Swap<size, big_endian>::writeval(pov + 8, offset);
|
|
elfcpp::Swap<size, big_endian>::writeval(pov + 8 + sizeof_addr, addend);
|
|
of->write_output_view(pov - view, incr_reloc_size, view);
|
|
}
|
|
}
|
|
|
|
// Create merge hash tables for the local symbols. These are used to
|
|
// speed up relocations.
|
|
|
|
template<int size, bool big_endian>
|
|
void
|
|
Sized_relobj_file<size, big_endian>::initialize_input_to_output_maps()
|
|
{
|
|
const unsigned int loccount = this->local_symbol_count_;
|
|
for (unsigned int i = 1; i < loccount; ++i)
|
|
{
|
|
Symbol_value<size>& lv(this->local_values_[i]);
|
|
lv.initialize_input_to_output_map(this);
|
|
}
|
|
}
|
|
|
|
// Free merge hash tables for the local symbols.
|
|
|
|
template<int size, bool big_endian>
|
|
void
|
|
Sized_relobj_file<size, big_endian>::free_input_to_output_maps()
|
|
{
|
|
const unsigned int loccount = this->local_symbol_count_;
|
|
for (unsigned int i = 1; i < loccount; ++i)
|
|
{
|
|
Symbol_value<size>& lv(this->local_values_[i]);
|
|
lv.free_input_to_output_map();
|
|
}
|
|
}
|
|
|
|
// If an object was compiled with -fsplit-stack, this is called to
|
|
// check whether any relocations refer to functions defined in objects
|
|
// which were not compiled with -fsplit-stack. If they were, then we
|
|
// need to apply some target-specific adjustments to request
|
|
// additional stack space.
|
|
|
|
template<int size, bool big_endian>
|
|
void
|
|
Sized_relobj_file<size, big_endian>::split_stack_adjust(
|
|
const Symbol_table* symtab,
|
|
const unsigned char* pshdrs,
|
|
unsigned int sh_type,
|
|
unsigned int shndx,
|
|
const unsigned char* prelocs,
|
|
size_t reloc_count,
|
|
unsigned char* view,
|
|
section_size_type view_size,
|
|
Reloc_symbol_changes** reloc_map)
|
|
{
|
|
if (sh_type == elfcpp::SHT_REL)
|
|
this->split_stack_adjust_reltype<elfcpp::SHT_REL>(symtab, pshdrs, shndx,
|
|
prelocs, reloc_count,
|
|
view, view_size,
|
|
reloc_map);
|
|
else
|
|
{
|
|
gold_assert(sh_type == elfcpp::SHT_RELA);
|
|
this->split_stack_adjust_reltype<elfcpp::SHT_RELA>(symtab, pshdrs, shndx,
|
|
prelocs, reloc_count,
|
|
view, view_size,
|
|
reloc_map);
|
|
}
|
|
}
|
|
|
|
// Adjust for -fsplit-stack, templatized on the type of the relocation
|
|
// section.
|
|
|
|
template<int size, bool big_endian>
|
|
template<int sh_type>
|
|
void
|
|
Sized_relobj_file<size, big_endian>::split_stack_adjust_reltype(
|
|
const Symbol_table* symtab,
|
|
const unsigned char* pshdrs,
|
|
unsigned int shndx,
|
|
const unsigned char* prelocs,
|
|
size_t reloc_count,
|
|
unsigned char* view,
|
|
section_size_type view_size,
|
|
Reloc_symbol_changes** reloc_map)
|
|
{
|
|
typedef typename Reloc_types<sh_type, size, big_endian>::Reloc Reltype;
|
|
const int reloc_size = Reloc_types<sh_type, size, big_endian>::reloc_size;
|
|
|
|
size_t local_count = this->local_symbol_count();
|
|
|
|
std::vector<section_offset_type> non_split_refs;
|
|
|
|
const unsigned char* pr = prelocs;
|
|
for (size_t i = 0; i < reloc_count; ++i, pr += reloc_size)
|
|
{
|
|
Reltype reloc(pr);
|
|
|
|
typename elfcpp::Elf_types<size>::Elf_WXword r_info = reloc.get_r_info();
|
|
unsigned int r_sym = elfcpp::elf_r_sym<size>(r_info);
|
|
if (r_sym < local_count)
|
|
continue;
|
|
|
|
const Symbol* gsym = this->global_symbol(r_sym);
|
|
gold_assert(gsym != NULL);
|
|
if (gsym->is_forwarder())
|
|
gsym = symtab->resolve_forwards(gsym);
|
|
|
|
// See if this relocation refers to a function defined in an
|
|
// object compiled without -fsplit-stack. Note that we don't
|
|
// care about the type of relocation--this means that in some
|
|
// cases we will ask for a large stack unnecessarily, but this
|
|
// is not fatal. FIXME: Some targets have symbols which are
|
|
// functions but are not type STT_FUNC, e.g., STT_ARM_TFUNC.
|
|
if (!gsym->is_undefined()
|
|
&& gsym->source() == Symbol::FROM_OBJECT
|
|
&& !gsym->object()->uses_split_stack())
|
|
{
|
|
unsigned int r_type = elfcpp::elf_r_type<size>(reloc.get_r_info());
|
|
if (parameters->target().is_call_to_non_split(gsym, r_type))
|
|
{
|
|
section_offset_type offset =
|
|
convert_to_section_size_type(reloc.get_r_offset());
|
|
non_split_refs.push_back(offset);
|
|
}
|
|
}
|
|
}
|
|
|
|
if (non_split_refs.empty())
|
|
return;
|
|
|
|
// At this point, every entry in NON_SPLIT_REFS indicates a
|
|
// relocation which refers to a function in an object compiled
|
|
// without -fsplit-stack. We now have to convert that list into a
|
|
// set of offsets to functions. First, we find all the functions.
|
|
|
|
Function_offsets function_offsets;
|
|
this->find_functions(pshdrs, shndx, &function_offsets);
|
|
if (function_offsets.empty())
|
|
return;
|
|
|
|
// Now get a list of the function with references to non split-stack
|
|
// code.
|
|
|
|
Function_offsets calls_non_split;
|
|
for (std::vector<section_offset_type>::const_iterator p
|
|
= non_split_refs.begin();
|
|
p != non_split_refs.end();
|
|
++p)
|
|
{
|
|
Function_offsets::const_iterator low = function_offsets.lower_bound(*p);
|
|
if (low == function_offsets.end())
|
|
--low;
|
|
else if (low->first == *p)
|
|
;
|
|
else if (low == function_offsets.begin())
|
|
continue;
|
|
else
|
|
--low;
|
|
|
|
calls_non_split.insert(*low);
|
|
}
|
|
if (calls_non_split.empty())
|
|
return;
|
|
|
|
// Now we have a set of functions to adjust. The adjustments are
|
|
// target specific. Besides changing the output section view
|
|
// however, it likes, the target may request a relocation change
|
|
// from one global symbol name to another.
|
|
|
|
for (Function_offsets::const_iterator p = calls_non_split.begin();
|
|
p != calls_non_split.end();
|
|
++p)
|
|
{
|
|
std::string from;
|
|
std::string to;
|
|
parameters->target().calls_non_split(this, shndx, p->first, p->second,
|
|
view, view_size, &from, &to);
|
|
if (!from.empty())
|
|
{
|
|
gold_assert(!to.empty());
|
|
Symbol* tosym = NULL;
|
|
|
|
// Find relocations in the relevant function which are for
|
|
// FROM.
|
|
pr = prelocs;
|
|
for (size_t i = 0; i < reloc_count; ++i, pr += reloc_size)
|
|
{
|
|
Reltype reloc(pr);
|
|
|
|
typename elfcpp::Elf_types<size>::Elf_WXword r_info =
|
|
reloc.get_r_info();
|
|
unsigned int r_sym = elfcpp::elf_r_sym<size>(r_info);
|
|
if (r_sym < local_count)
|
|
continue;
|
|
|
|
section_offset_type offset =
|
|
convert_to_section_size_type(reloc.get_r_offset());
|
|
if (offset < p->first
|
|
|| (offset
|
|
>= (p->first
|
|
+ static_cast<section_offset_type>(p->second))))
|
|
continue;
|
|
|
|
const Symbol* gsym = this->global_symbol(r_sym);
|
|
if (from == gsym->name())
|
|
{
|
|
if (tosym == NULL)
|
|
{
|
|
tosym = symtab->lookup(to.c_str());
|
|
if (tosym == NULL)
|
|
{
|
|
this->error(_("could not convert call "
|
|
"to '%s' to '%s'"),
|
|
from.c_str(), to.c_str());
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (*reloc_map == NULL)
|
|
*reloc_map = new Reloc_symbol_changes(reloc_count);
|
|
(*reloc_map)->set(i, tosym);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Find all the function in this object defined in section SHNDX.
|
|
// Store their offsets in the section in FUNCTION_OFFSETS.
|
|
|
|
template<int size, bool big_endian>
|
|
void
|
|
Sized_relobj_file<size, big_endian>::find_functions(
|
|
const unsigned char* pshdrs,
|
|
unsigned int shndx,
|
|
Sized_relobj_file<size, big_endian>::Function_offsets* function_offsets)
|
|
{
|
|
// We need to read the symbols to find the functions. If we wanted
|
|
// to, we could cache reading the symbols across all sections in the
|
|
// object.
|
|
const unsigned int symtab_shndx = this->symtab_shndx_;
|
|
typename This::Shdr symtabshdr(pshdrs + symtab_shndx * This::shdr_size);
|
|
gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
|
|
|
|
typename elfcpp::Elf_types<size>::Elf_WXword sh_size =
|
|
symtabshdr.get_sh_size();
|
|
const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(),
|
|
sh_size, true, true);
|
|
|
|
const int sym_size = This::sym_size;
|
|
const unsigned int symcount = sh_size / sym_size;
|
|
for (unsigned int i = 0; i < symcount; ++i, psyms += sym_size)
|
|
{
|
|
typename elfcpp::Sym<size, big_endian> isym(psyms);
|
|
|
|
// FIXME: Some targets can have functions which do not have type
|
|
// STT_FUNC, e.g., STT_ARM_TFUNC.
|
|
if (isym.get_st_type() != elfcpp::STT_FUNC
|
|
|| isym.get_st_size() == 0)
|
|
continue;
|
|
|
|
bool is_ordinary;
|
|
unsigned int sym_shndx = this->adjust_sym_shndx(i, isym.get_st_shndx(),
|
|
&is_ordinary);
|
|
if (!is_ordinary || sym_shndx != shndx)
|
|
continue;
|
|
|
|
section_offset_type value =
|
|
convert_to_section_size_type(isym.get_st_value());
|
|
section_size_type fnsize =
|
|
convert_to_section_size_type(isym.get_st_size());
|
|
|
|
(*function_offsets)[value] = fnsize;
|
|
}
|
|
}
|
|
|
|
// Class Merged_symbol_value.
|
|
|
|
template<int size>
|
|
void
|
|
Merged_symbol_value<size>::initialize_input_to_output_map(
|
|
const Relobj* object,
|
|
unsigned int input_shndx)
|
|
{
|
|
Object_merge_map* map = object->merge_map();
|
|
map->initialize_input_to_output_map<size>(input_shndx,
|
|
this->output_start_address_,
|
|
&this->output_addresses_);
|
|
}
|
|
|
|
// Get the output value corresponding to an input offset if we
|
|
// couldn't find it in the hash table.
|
|
|
|
template<int size>
|
|
typename elfcpp::Elf_types<size>::Elf_Addr
|
|
Merged_symbol_value<size>::value_from_output_section(
|
|
const Relobj* object,
|
|
unsigned int input_shndx,
|
|
typename elfcpp::Elf_types<size>::Elf_Addr input_offset) const
|
|
{
|
|
section_offset_type output_offset;
|
|
bool found = object->merge_map()->get_output_offset(NULL, input_shndx,
|
|
input_offset,
|
|
&output_offset);
|
|
|
|
// If this assertion fails, it means that some relocation was
|
|
// against a portion of an input merge section which we didn't map
|
|
// to the output file and we didn't explicitly discard. We should
|
|
// always map all portions of input merge sections.
|
|
gold_assert(found);
|
|
|
|
if (output_offset == -1)
|
|
return 0;
|
|
else
|
|
return this->output_start_address_ + output_offset;
|
|
}
|
|
|
|
// Track_relocs methods.
|
|
|
|
// Initialize the class to track the relocs. This gets the object,
|
|
// the reloc section index, and the type of the relocs. This returns
|
|
// false if something goes wrong.
|
|
|
|
template<int size, bool big_endian>
|
|
bool
|
|
Track_relocs<size, big_endian>::initialize(
|
|
Object* object,
|
|
unsigned int reloc_shndx,
|
|
unsigned int reloc_type)
|
|
{
|
|
// If RELOC_SHNDX is -1U, it means there is more than one reloc
|
|
// section for the .eh_frame section. We can't handle that case.
|
|
if (reloc_shndx == -1U)
|
|
return false;
|
|
|
|
// If RELOC_SHNDX is 0, there is no reloc section.
|
|
if (reloc_shndx == 0)
|
|
return true;
|
|
|
|
// Get the contents of the reloc section.
|
|
this->prelocs_ = object->section_contents(reloc_shndx, &this->len_, false);
|
|
|
|
if (reloc_type == elfcpp::SHT_REL)
|
|
this->reloc_size_ = elfcpp::Elf_sizes<size>::rel_size;
|
|
else if (reloc_type == elfcpp::SHT_RELA)
|
|
this->reloc_size_ = elfcpp::Elf_sizes<size>::rela_size;
|
|
else
|
|
gold_unreachable();
|
|
|
|
if (this->len_ % this->reloc_size_ != 0)
|
|
{
|
|
object->error(_("reloc section size %zu is not a multiple of "
|
|
"reloc size %d\n"),
|
|
static_cast<size_t>(this->len_),
|
|
this->reloc_size_);
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
// Return the offset of the next reloc, or -1 if there isn't one.
|
|
|
|
template<int size, bool big_endian>
|
|
off_t
|
|
Track_relocs<size, big_endian>::next_offset() const
|
|
{
|
|
if (this->pos_ >= this->len_)
|
|
return -1;
|
|
|
|
// Rel and Rela start out the same, so we can always use Rel to find
|
|
// the r_offset value.
|
|
elfcpp::Rel<size, big_endian> rel(this->prelocs_ + this->pos_);
|
|
return rel.get_r_offset();
|
|
}
|
|
|
|
// Return the index of the symbol referenced by the next reloc, or -1U
|
|
// if there aren't any more relocs.
|
|
|
|
template<int size, bool big_endian>
|
|
unsigned int
|
|
Track_relocs<size, big_endian>::next_symndx() const
|
|
{
|
|
if (this->pos_ >= this->len_)
|
|
return -1U;
|
|
|
|
// Rel and Rela start out the same, so we can use Rel to find the
|
|
// symbol index.
|
|
elfcpp::Rel<size, big_endian> rel(this->prelocs_ + this->pos_);
|
|
return elfcpp::elf_r_sym<size>(rel.get_r_info());
|
|
}
|
|
|
|
// Return the addend of the next reloc, or 0 if there isn't one.
|
|
|
|
template<int size, bool big_endian>
|
|
uint64_t
|
|
Track_relocs<size, big_endian>::next_addend() const
|
|
{
|
|
if (this->pos_ >= this->len_)
|
|
return 0;
|
|
if (this->reloc_size_ == elfcpp::Elf_sizes<size>::rel_size)
|
|
return 0;
|
|
elfcpp::Rela<size, big_endian> rela(this->prelocs_ + this->pos_);
|
|
return rela.get_r_addend();
|
|
}
|
|
|
|
// Advance to the next reloc whose r_offset is greater than or equal
|
|
// to OFFSET. Return the number of relocs we skip.
|
|
|
|
template<int size, bool big_endian>
|
|
int
|
|
Track_relocs<size, big_endian>::advance(off_t offset)
|
|
{
|
|
int ret = 0;
|
|
while (this->pos_ < this->len_)
|
|
{
|
|
// Rel and Rela start out the same, so we can always use Rel to
|
|
// find the r_offset value.
|
|
elfcpp::Rel<size, big_endian> rel(this->prelocs_ + this->pos_);
|
|
if (static_cast<off_t>(rel.get_r_offset()) >= offset)
|
|
break;
|
|
++ret;
|
|
this->pos_ += this->reloc_size_;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
// Instantiate the templates we need.
|
|
|
|
#ifdef HAVE_TARGET_32_LITTLE
|
|
template
|
|
void
|
|
Sized_relobj_file<32, false>::do_read_relocs(Read_relocs_data* rd);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_32_BIG
|
|
template
|
|
void
|
|
Sized_relobj_file<32, true>::do_read_relocs(Read_relocs_data* rd);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_LITTLE
|
|
template
|
|
void
|
|
Sized_relobj_file<64, false>::do_read_relocs(Read_relocs_data* rd);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_BIG
|
|
template
|
|
void
|
|
Sized_relobj_file<64, true>::do_read_relocs(Read_relocs_data* rd);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_32_LITTLE
|
|
template
|
|
void
|
|
Sized_relobj_file<32, false>::do_gc_process_relocs(Symbol_table* symtab,
|
|
Layout* layout,
|
|
Read_relocs_data* rd);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_32_BIG
|
|
template
|
|
void
|
|
Sized_relobj_file<32, true>::do_gc_process_relocs(Symbol_table* symtab,
|
|
Layout* layout,
|
|
Read_relocs_data* rd);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_LITTLE
|
|
template
|
|
void
|
|
Sized_relobj_file<64, false>::do_gc_process_relocs(Symbol_table* symtab,
|
|
Layout* layout,
|
|
Read_relocs_data* rd);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_BIG
|
|
template
|
|
void
|
|
Sized_relobj_file<64, true>::do_gc_process_relocs(Symbol_table* symtab,
|
|
Layout* layout,
|
|
Read_relocs_data* rd);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_32_LITTLE
|
|
template
|
|
void
|
|
Sized_relobj_file<32, false>::do_scan_relocs(Symbol_table* symtab,
|
|
Layout* layout,
|
|
Read_relocs_data* rd);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_32_BIG
|
|
template
|
|
void
|
|
Sized_relobj_file<32, true>::do_scan_relocs(Symbol_table* symtab,
|
|
Layout* layout,
|
|
Read_relocs_data* rd);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_LITTLE
|
|
template
|
|
void
|
|
Sized_relobj_file<64, false>::do_scan_relocs(Symbol_table* symtab,
|
|
Layout* layout,
|
|
Read_relocs_data* rd);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_BIG
|
|
template
|
|
void
|
|
Sized_relobj_file<64, true>::do_scan_relocs(Symbol_table* symtab,
|
|
Layout* layout,
|
|
Read_relocs_data* rd);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_32_LITTLE
|
|
template
|
|
void
|
|
Sized_relobj_file<32, false>::do_relocate(const Symbol_table* symtab,
|
|
const Layout* layout,
|
|
Output_file* of);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_32_BIG
|
|
template
|
|
void
|
|
Sized_relobj_file<32, true>::do_relocate(const Symbol_table* symtab,
|
|
const Layout* layout,
|
|
Output_file* of);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_LITTLE
|
|
template
|
|
void
|
|
Sized_relobj_file<64, false>::do_relocate(const Symbol_table* symtab,
|
|
const Layout* layout,
|
|
Output_file* of);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_BIG
|
|
template
|
|
void
|
|
Sized_relobj_file<64, true>::do_relocate(const Symbol_table* symtab,
|
|
const Layout* layout,
|
|
Output_file* of);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_32_LITTLE
|
|
template
|
|
void
|
|
Sized_relobj_file<32, false>::do_relocate_sections(
|
|
const Symbol_table* symtab,
|
|
const Layout* layout,
|
|
const unsigned char* pshdrs,
|
|
Output_file* of,
|
|
Views* pviews);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_32_BIG
|
|
template
|
|
void
|
|
Sized_relobj_file<32, true>::do_relocate_sections(
|
|
const Symbol_table* symtab,
|
|
const Layout* layout,
|
|
const unsigned char* pshdrs,
|
|
Output_file* of,
|
|
Views* pviews);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_LITTLE
|
|
template
|
|
void
|
|
Sized_relobj_file<64, false>::do_relocate_sections(
|
|
const Symbol_table* symtab,
|
|
const Layout* layout,
|
|
const unsigned char* pshdrs,
|
|
Output_file* of,
|
|
Views* pviews);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_BIG
|
|
template
|
|
void
|
|
Sized_relobj_file<64, true>::do_relocate_sections(
|
|
const Symbol_table* symtab,
|
|
const Layout* layout,
|
|
const unsigned char* pshdrs,
|
|
Output_file* of,
|
|
Views* pviews);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_32_LITTLE
|
|
template
|
|
void
|
|
Sized_relobj_file<32, false>::initialize_input_to_output_maps();
|
|
|
|
template
|
|
void
|
|
Sized_relobj_file<32, false>::free_input_to_output_maps();
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_32_BIG
|
|
template
|
|
void
|
|
Sized_relobj_file<32, true>::initialize_input_to_output_maps();
|
|
|
|
template
|
|
void
|
|
Sized_relobj_file<32, true>::free_input_to_output_maps();
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_LITTLE
|
|
template
|
|
void
|
|
Sized_relobj_file<64, false>::initialize_input_to_output_maps();
|
|
|
|
template
|
|
void
|
|
Sized_relobj_file<64, false>::free_input_to_output_maps();
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_BIG
|
|
template
|
|
void
|
|
Sized_relobj_file<64, true>::initialize_input_to_output_maps();
|
|
|
|
template
|
|
void
|
|
Sized_relobj_file<64, true>::free_input_to_output_maps();
|
|
#endif
|
|
|
|
#if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
|
|
template
|
|
class Merged_symbol_value<32>;
|
|
#endif
|
|
|
|
#if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
|
|
template
|
|
class Merged_symbol_value<64>;
|
|
#endif
|
|
|
|
#if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_32_BIG)
|
|
template
|
|
class Symbol_value<32>;
|
|
#endif
|
|
|
|
#if defined(HAVE_TARGET_64_LITTLE) || defined(HAVE_TARGET_64_BIG)
|
|
template
|
|
class Symbol_value<64>;
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_32_LITTLE
|
|
template
|
|
class Track_relocs<32, false>;
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_32_BIG
|
|
template
|
|
class Track_relocs<32, true>;
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_LITTLE
|
|
template
|
|
class Track_relocs<64, false>;
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_BIG
|
|
template
|
|
class Track_relocs<64, true>;
|
|
#endif
|
|
|
|
} // End namespace gold.
|