You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
1900 lines
54 KiB
1900 lines
54 KiB
// reloc.cc -- relocate input files for gold. |
|
|
|
// Copyright (C) 2006-2014 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_); |
|
|
|
// When defer_object_cleanup_ is true, we do cleanup work at the end of |
|
// Relocstub_task. |
|
if (!this->defer_object_cleanup_) { |
|
// This is normally the last thing we will do with an object, so |
|
// uncache all views. |
|
this->object_->clear_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(); |
|
} |
|
|
|
std::string |
|
Relocstub_task::get_name() const |
|
{ |
|
return "Relocstub_task " + this->object_->name(); |
|
} |
|
|
|
void |
|
Relocstub_task::run(Workqueue*) |
|
{ |
|
this->object_->relocate_stub_tables(this->symtab_, this->layout_); |
|
|
|
// This is normally the last thing we will do with an object, so |
|
// uncache all views. |
|
this->object_->clear_views(); |
|
this->object_->clear_view_cache_marks(); |
|
this->object_->release(); |
|
|
|
} |
|
|
|
// 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" created here is either discarded at the end of "Relocate_task" or |
|
// "Relocstub_task", depending whether the latter ones are needed. |
|
Views& views = *(this->create_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(layout, 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_ctors_reverse_view) |
|
this->reverse_words(views[i].view, views[i].view_size); |
|
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()); |
|
} |
|
|
|
template<int size, bool big_endian> |
|
void |
|
Sized_relobj<size, big_endian>::do_relocate_stub_tables(const Symbol_table*, const Layout*) |
|
{} |
|
|
|
// 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 Layout* layout, |
|
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; |
|
pvs->is_ctors_reverse_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(); |
|
pvs->is_ctors_reverse_view = |
|
(!parameters->options().relocatable() |
|
&& view_size > size / 8 |
|
&& (strcmp(os->name(), ".init_array") == 0 |
|
|| strcmp(os->name(), ".fini_array") == 0) |
|
&& layout->is_ctors_in_init_array(this, i)); |
|
} |
|
|
|
// 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()) |
|
{ |
|
Relocatable_relocs* rr = this->relocatable_relocs(i); |
|
target->relocate_relocs(&relinfo, sh_type, prelocs, reloc_count, |
|
os, output_offset, rr, |
|
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_relocs(&relinfo, sh_type, prelocs, reloc_count, |
|
os, output_offset, rr, |
|
view, address, view_size, |
|
(*pviews)[i].view, |
|
(*pviews)[i].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; |
|
} |
|
} |
|
|
|
// Reverse the words in a section. Used for .ctors sections mapped to |
|
// .init_array sections. See ctors_sections_in_init_array in |
|
// layout.cc. |
|
|
|
template<int size, bool big_endian> |
|
void |
|
Sized_relobj_file<size, big_endian>::reverse_words(unsigned char* view, |
|
section_size_type view_size) |
|
{ |
|
typedef typename elfcpp::Swap<size, big_endian>::Valtype Valtype; |
|
Valtype* vview = reinterpret_cast<Valtype*>(view); |
|
section_size_type vview_size = view_size / (size / 8); |
|
for (section_size_type i = 0; i < vview_size / 2; ++i) |
|
{ |
|
Valtype tmp = vview[i]; |
|
vview[i] = vview[vview_size - 1 - i]; |
|
vview[vview_size - 1 - i] = tmp; |
|
} |
|
} |
|
|
|
// 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); |
|
|
|
template |
|
void |
|
Sized_relobj<32, false>::do_relocate_stub_tables(const Symbol_table* symtab, |
|
const Layout* layout); |
|
|
|
#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); |
|
|
|
template |
|
void |
|
Sized_relobj<32, true>::do_relocate_stub_tables(const Symbol_table* symtab, |
|
const Layout* layout); |
|
#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); |
|
|
|
template |
|
void |
|
Sized_relobj<64, false>::do_relocate_stub_tables(const Symbol_table* symtab, |
|
const Layout* layout); |
|
#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); |
|
|
|
template |
|
void |
|
Sized_relobj<64, true>::do_relocate_stub_tables(const Symbol_table* symtab, |
|
const Layout* layout); |
|
#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.
|
|
|