diff options
author | Ian Lance Taylor <iant@google.com> | 2006-10-20 20:40:49 +0000 |
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committer | Ian Lance Taylor <iant@google.com> | 2006-10-20 20:40:49 +0000 |
commit | 92e059d8dc78c3f65e29e48e368f6e47ea0ab671 (patch) | |
tree | f448eb3317d9cbb0f5946422cc28ef157a5f65cb /gold/reloc.cc | |
parent | af4658dc3db33004d6166b161588221ecb463a5f (diff) | |
download | gdb-92e059d8dc78c3f65e29e48e368f6e47ea0ab671.zip gdb-92e059d8dc78c3f65e29e48e368f6e47ea0ab671.tar.gz gdb-92e059d8dc78c3f65e29e48e368f6e47ea0ab671.tar.bz2 |
Framework for relocation scanning. Implement simple static TLS
relocations.
Diffstat (limited to 'gold/reloc.cc')
-rw-r--r-- | gold/reloc.cc | 311 |
1 files changed, 290 insertions, 21 deletions
diff --git a/gold/reloc.cc b/gold/reloc.cc index 905eeae..bb672e4 100644 --- a/gold/reloc.cc +++ b/gold/reloc.cc @@ -10,6 +10,86 @@ 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::Is_runnable_type +Read_relocs::is_runnable(Workqueue*) +{ + return this->object_->is_locked() ? IS_LOCKED : IS_RUNNABLE; +} + +// Lock the file. + +Task_locker* +Read_relocs::locks(Workqueue*) +{ + return new Task_locker_obj<Object>(*this->object_); +} + +// 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); + workqueue->queue_front(new Scan_relocs(this->options_, this->symtab_, + this->object_, rd, this->symtab_lock_, + this->blocker_)); +} + +// Scan_relocs methods. + +// 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::Is_runnable_type +Scan_relocs::is_runnable(Workqueue*) +{ + return this->symtab_lock_->is_writable() ? IS_RUNNABLE : IS_LOCKED; +} + +// Return the locks we hold: one on the file, one on the symbol table +// and one blocker. + +class Scan_relocs::Scan_relocs_locker : public Task_locker +{ + public: + Scan_relocs_locker(Object* object, Task_token& symtab_lock, Task* task, + Task_token& blocker, Workqueue* workqueue) + : objlock_(*object), symtab_locker_(symtab_lock, task), + blocker_(blocker, workqueue) + { } + + private: + Task_locker_obj<Object> objlock_; + Task_locker_write symtab_locker_; + Task_locker_block blocker_; +}; + +Task_locker* +Scan_relocs::locks(Workqueue* workqueue) +{ + return new Scan_relocs_locker(this->object_, *this->symtab_lock_, this, + *this->blocker_, workqueue); +} + +// Scan the relocs. + +void +Scan_relocs::run(Workqueue*) +{ + this->object_->scan_relocs(this->options_, this->symtab_, this->rd_); + delete this->rd_; + this->rd_ = NULL; +} + // Relocate_task methods. // These tasks are always runnable. @@ -48,17 +128,154 @@ Relocate_task::locks(Workqueue* workqueue) void Relocate_task::run(Workqueue*) { - this->object_->relocate(this->options_, this->symtab_, this->sympool_, + this->object_->relocate(this->options_, this->symtab_, this->layout_, this->of_); } +// Read the relocs and local symbols from the object file and store +// the information in RD. + +template<int size, bool big_endian> +void +Sized_object<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 unsigned char *pshdrs = this->get_view(this->shoff_, + shnum * This::shdr_size); + // 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 = shdr.get_sh_info(); + if (shndx >= shnum) + { + fprintf(stderr, _("%s: %s: relocation section %u has bad info %u\n"), + program_name, this->name().c_str(), i, shndx); + gold_exit(false); + } + + if (!this->is_section_included(shndx)) + continue; + + if (shdr.get_sh_link() != this->symtab_shnum_) + { + fprintf(stderr, + _("%s: %s: relocation section %u uses unexpected " + "symbol table %u\n"), + program_name, this->name().c_str(), i, shdr.get_sh_link()); + gold_exit(false); + } + + off_t sh_size = shdr.get_sh_size(); + + 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()) + { + fprintf(stderr, + _("%s: %s: unexpected entsize for reloc section %u: " + "%lu != %u"), + program_name, this->name().c_str(), i, + static_cast<unsigned long>(shdr.get_sh_entsize()), + reloc_size); + gold_exit(false); + } + + size_t reloc_count = sh_size / reloc_size; + if (reloc_count * reloc_size != sh_size) + { + fprintf(stderr, _("%s: %s: reloc section %u size %lu uneven"), + program_name, this->name().c_str(), i, + static_cast<unsigned long>(sh_size)); + gold_exit(false); + } + + 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); + sr.sh_type = sh_type; + sr.reloc_count = reloc_count; + } + + // Read the local symbols. + if (this->symtab_shnum_ == 0 || this->local_symbol_count_ == 0) + rd->local_symbols = NULL; + else + { + typename This::Shdr symtabshdr(pshdrs + + this->symtab_shnum_ * This::shdr_size); + assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB); + const int sym_size = This::sym_size; + const unsigned int loccount = this->local_symbol_count_; + assert(loccount == symtabshdr.get_sh_info()); + off_t locsize = loccount * sym_size; + rd->local_symbols = this->get_lasting_view(symtabshdr.get_sh_offset(), + locsize); + } +} + +// 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_object<size, big_endian>::do_scan_relocs(const General_options& options, + Symbol_table* symtab, + Read_relocs_data* rd) +{ + Sized_target<size, big_endian>* target = this->sized_target(); + + 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) + { + target->scan_relocs(options, symtab, this, p->sh_type, + p->contents->data(), p->reloc_count, + this->local_symbol_count_, + local_symbols, + this->symbols_); + delete p->contents; + p->contents = NULL; + } + + if (rd->local_symbols != NULL) + { + delete rd->local_symbols; + rd->local_symbols = NULL; + } +} + // Relocate the input sections and write out the local symbols. template<int size, bool big_endian> void -Sized_object<size, big_endian>::do_relocate(const General_options&, +Sized_object<size, big_endian>::do_relocate(const General_options& options, const Symbol_table* symtab, - const Stringpool* sympool, + const Layout* layout, Output_file* of) { unsigned int shnum = this->shnum(); @@ -78,7 +295,7 @@ Sized_object<size, big_endian>::do_relocate(const General_options&, // Apply relocations. - this->relocate_sections(symtab, pshdrs, &views); + this->relocate_sections(options, symtab, layout, pshdrs, &views); // Write out the accumulated views. for (unsigned int i = 1; i < shnum; ++i) @@ -89,7 +306,7 @@ Sized_object<size, big_endian>::do_relocate(const General_options&, } // Write out the local symbols. - this->write_local_symbols(of, sympool); + this->write_local_symbols(of, layout->sympool()); } // Write section data to the output file. PSHDRS points to the @@ -127,9 +344,8 @@ Sized_object<size, big_endian>::write_sections(const unsigned char* pshdrs, off_t sh_size = shdr.get_sh_size(); unsigned char* view = of->get_output_view(start, sh_size); - this->input_file()->file().read(shdr.get_sh_offset(), - sh_size, - view); + this->read(shdr.get_sh_offset(), sh_size, view); + pvs->view = view; pvs->address = os->address() + map_sections[i].offset; pvs->offset = start; @@ -142,14 +358,25 @@ Sized_object<size, big_endian>::write_sections(const unsigned char* pshdrs, template<int size, bool big_endian> void -Sized_object<size, big_endian>::relocate_sections(const Symbol_table* symtab, - const unsigned char* pshdrs, - Views* pviews) +Sized_object<size, big_endian>::relocate_sections( + const General_options& options, + const Symbol_table* symtab, + const Layout* layout, + const unsigned char* pshdrs, + Views* pviews) { unsigned int shnum = this->shnum(); - std::vector<Map_to_output>& map_sections(this->map_to_output()); Sized_target<size, big_endian>* target = this->sized_target(); + Relocate_info<size, big_endian> relinfo; + relinfo.options = &options; + relinfo.symtab = symtab; + relinfo.layout = layout; + relinfo.object = this; + relinfo.local_symbol_count = this->local_symbol_count_; + relinfo.values = this->values_; + relinfo.symbols = this->symbols_; + const unsigned char* p = pshdrs + This::shdr_size; for (unsigned int i = 1; i < shnum; ++i, p += This::shdr_size) { @@ -167,7 +394,7 @@ Sized_object<size, big_endian>::relocate_sections(const Symbol_table* symtab, gold_exit(false); } - if (map_sections[index].output_section == NULL) + if (!this->is_section_included(index)) { // This relocation section is against a section which we // discarded. @@ -215,10 +442,12 @@ Sized_object<size, big_endian>::relocate_sections(const Symbol_table* symtab, gold_exit(false); } - target->relocate_section(symtab, this, sh_type, prelocs, reloc_count, - this->local_symbol_count_, - this->values_, - this->symbols_, + relinfo.reloc_shndx = i; + relinfo.data_shndx = index; + target->relocate_section(&relinfo, + sh_type, + prelocs, + reloc_count, (*pviews)[index].view, (*pviews)[index].address, (*pviews)[index].view_size); @@ -230,30 +459,70 @@ Sized_object<size, big_endian>::relocate_sections(const Symbol_table* symtab, template void +Sized_object<32, false>::do_read_relocs(Read_relocs_data* rd); + +template +void +Sized_object<32, true>::do_read_relocs(Read_relocs_data* rd); + +template +void +Sized_object<64, false>::do_read_relocs(Read_relocs_data* rd); + +template +void +Sized_object<64, true>::do_read_relocs(Read_relocs_data* rd); + +template +void +Sized_object<32, false>::do_scan_relocs(const General_options& options, + Symbol_table* symtab, + Read_relocs_data* rd); + +template +void +Sized_object<32, true>::do_scan_relocs(const General_options& options, + Symbol_table* symtab, + Read_relocs_data* rd); + +template +void +Sized_object<64, false>::do_scan_relocs(const General_options& options, + Symbol_table* symtab, + Read_relocs_data* rd); + +template +void +Sized_object<64, true>::do_scan_relocs(const General_options& options, + Symbol_table* symtab, + Read_relocs_data* rd); + +template +void Sized_object<32, false>::do_relocate(const General_options& options, const Symbol_table* symtab, - const Stringpool* sympool, + const Layout* layout, Output_file* of); template void Sized_object<32, true>::do_relocate(const General_options& options, const Symbol_table* symtab, - const Stringpool* sympool, + const Layout* layout, Output_file* of); template void Sized_object<64, false>::do_relocate(const General_options& options, const Symbol_table* symtab, - const Stringpool* sympool, + const Layout* layout, Output_file* of); template void Sized_object<64, true>::do_relocate(const General_options& options, const Symbol_table* symtab, - const Stringpool* sympool, + const Layout* layout, Output_file* of); |