| // object.cc -- support for an object file for linking in gold |
| |
| // Copyright (C) 2006-2021 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 <cerrno> |
| #include <cstring> |
| #include <cstdarg> |
| #include "demangle.h" |
| #include "libiberty.h" |
| |
| #include "gc.h" |
| #include "target-select.h" |
| #include "dwarf_reader.h" |
| #include "layout.h" |
| #include "output.h" |
| #include "symtab.h" |
| #include "cref.h" |
| #include "reloc.h" |
| #include "object.h" |
| #include "dynobj.h" |
| #include "plugin.h" |
| #include "compressed_output.h" |
| #include "incremental.h" |
| #include "merge.h" |
| |
| namespace gold |
| { |
| |
| // Struct Read_symbols_data. |
| |
| // Destroy any remaining File_view objects and buffers of decompressed |
| // sections. |
| |
| Read_symbols_data::~Read_symbols_data() |
| { |
| if (this->section_headers != NULL) |
| delete this->section_headers; |
| if (this->section_names != NULL) |
| delete this->section_names; |
| if (this->symbols != NULL) |
| delete this->symbols; |
| if (this->symbol_names != NULL) |
| delete this->symbol_names; |
| if (this->versym != NULL) |
| delete this->versym; |
| if (this->verdef != NULL) |
| delete this->verdef; |
| if (this->verneed != NULL) |
| delete this->verneed; |
| } |
| |
| // Class Xindex. |
| |
| // Initialize the symtab_xindex_ array. Find the SHT_SYMTAB_SHNDX |
| // section and read it in. SYMTAB_SHNDX is the index of the symbol |
| // table we care about. |
| |
| template<int size, bool big_endian> |
| void |
| Xindex::initialize_symtab_xindex(Object* object, unsigned int symtab_shndx) |
| { |
| if (!this->symtab_xindex_.empty()) |
| return; |
| |
| gold_assert(symtab_shndx != 0); |
| |
| // Look through the sections in reverse order, on the theory that it |
| // is more likely to be near the end than the beginning. |
| unsigned int i = object->shnum(); |
| while (i > 0) |
| { |
| --i; |
| if (object->section_type(i) == elfcpp::SHT_SYMTAB_SHNDX |
| && this->adjust_shndx(object->section_link(i)) == symtab_shndx) |
| { |
| this->read_symtab_xindex<size, big_endian>(object, i, NULL); |
| return; |
| } |
| } |
| |
| object->error(_("missing SHT_SYMTAB_SHNDX section")); |
| } |
| |
| // Read in the symtab_xindex_ array, given the section index of the |
| // SHT_SYMTAB_SHNDX section. If PSHDRS is not NULL, it points at the |
| // section headers. |
| |
| template<int size, bool big_endian> |
| void |
| Xindex::read_symtab_xindex(Object* object, unsigned int xindex_shndx, |
| const unsigned char* pshdrs) |
| { |
| section_size_type bytecount; |
| const unsigned char* contents; |
| if (pshdrs == NULL) |
| contents = object->section_contents(xindex_shndx, &bytecount, false); |
| else |
| { |
| const unsigned char* p = (pshdrs |
| + (xindex_shndx |
| * elfcpp::Elf_sizes<size>::shdr_size)); |
| typename elfcpp::Shdr<size, big_endian> shdr(p); |
| bytecount = convert_to_section_size_type(shdr.get_sh_size()); |
| contents = object->get_view(shdr.get_sh_offset(), bytecount, true, false); |
| } |
| |
| gold_assert(this->symtab_xindex_.empty()); |
| this->symtab_xindex_.reserve(bytecount / 4); |
| for (section_size_type i = 0; i < bytecount; i += 4) |
| { |
| unsigned int shndx = elfcpp::Swap<32, big_endian>::readval(contents + i); |
| // We preadjust the section indexes we save. |
| this->symtab_xindex_.push_back(this->adjust_shndx(shndx)); |
| } |
| } |
| |
| // Symbol symndx has a section of SHN_XINDEX; return the real section |
| // index. |
| |
| unsigned int |
| Xindex::sym_xindex_to_shndx(Object* object, unsigned int symndx) |
| { |
| if (symndx >= this->symtab_xindex_.size()) |
| { |
| object->error(_("symbol %u out of range for SHT_SYMTAB_SHNDX section"), |
| symndx); |
| return elfcpp::SHN_UNDEF; |
| } |
| unsigned int shndx = this->symtab_xindex_[symndx]; |
| if (shndx < elfcpp::SHN_LORESERVE || shndx >= object->shnum()) |
| { |
| object->error(_("extended index for symbol %u out of range: %u"), |
| symndx, shndx); |
| return elfcpp::SHN_UNDEF; |
| } |
| return shndx; |
| } |
| |
| // Class Object. |
| |
| // Report an error for this object file. This is used by the |
| // elfcpp::Elf_file interface, and also called by the Object code |
| // itself. |
| |
| void |
| Object::error(const char* format, ...) const |
| { |
| va_list args; |
| va_start(args, format); |
| char* buf = NULL; |
| if (vasprintf(&buf, format, args) < 0) |
| gold_nomem(); |
| va_end(args); |
| gold_error(_("%s: %s"), this->name().c_str(), buf); |
| free(buf); |
| } |
| |
| // Return a view of the contents of a section. |
| |
| const unsigned char* |
| Object::section_contents(unsigned int shndx, section_size_type* plen, |
| bool cache) |
| { return this->do_section_contents(shndx, plen, cache); } |
| |
| // Read the section data into SD. This is code common to Sized_relobj_file |
| // and Sized_dynobj, so we put it into Object. |
| |
| template<int size, bool big_endian> |
| void |
| Object::read_section_data(elfcpp::Elf_file<size, big_endian, Object>* elf_file, |
| Read_symbols_data* sd) |
| { |
| const int shdr_size = elfcpp::Elf_sizes<size>::shdr_size; |
| |
| // Read the section headers. |
| const off_t shoff = elf_file->shoff(); |
| const unsigned int shnum = this->shnum(); |
| sd->section_headers = this->get_lasting_view(shoff, shnum * shdr_size, |
| true, true); |
| |
| // Read the section names. |
| const unsigned char* pshdrs = sd->section_headers->data(); |
| const unsigned char* pshdrnames = pshdrs + elf_file->shstrndx() * shdr_size; |
| typename elfcpp::Shdr<size, big_endian> shdrnames(pshdrnames); |
| |
| if (shdrnames.get_sh_type() != elfcpp::SHT_STRTAB) |
| this->error(_("section name section has wrong type: %u"), |
| static_cast<unsigned int>(shdrnames.get_sh_type())); |
| |
| sd->section_names_size = |
| convert_to_section_size_type(shdrnames.get_sh_size()); |
| sd->section_names = this->get_lasting_view(shdrnames.get_sh_offset(), |
| sd->section_names_size, false, |
| false); |
| } |
| |
| // If NAME is the name of a special .gnu.warning section, arrange for |
| // the warning to be issued. SHNDX is the section index. Return |
| // whether it is a warning section. |
| |
| bool |
| Object::handle_gnu_warning_section(const char* name, unsigned int shndx, |
| Symbol_table* symtab) |
| { |
| const char warn_prefix[] = ".gnu.warning."; |
| const int warn_prefix_len = sizeof warn_prefix - 1; |
| if (strncmp(name, warn_prefix, warn_prefix_len) == 0) |
| { |
| // Read the section contents to get the warning text. It would |
| // be nicer if we only did this if we have to actually issue a |
| // warning. Unfortunately, warnings are issued as we relocate |
| // sections. That means that we can not lock the object then, |
| // as we might try to issue the same warning multiple times |
| // simultaneously. |
| section_size_type len; |
| const unsigned char* contents = this->section_contents(shndx, &len, |
| false); |
| if (len == 0) |
| { |
| const char* warning = name + warn_prefix_len; |
| contents = reinterpret_cast<const unsigned char*>(warning); |
| len = strlen(warning); |
| } |
| std::string warning(reinterpret_cast<const char*>(contents), len); |
| symtab->add_warning(name + warn_prefix_len, this, warning); |
| return true; |
| } |
| return false; |
| } |
| |
| // If NAME is the name of the special section which indicates that |
| // this object was compiled with -fsplit-stack, mark it accordingly. |
| |
| bool |
| Object::handle_split_stack_section(const char* name) |
| { |
| if (strcmp(name, ".note.GNU-split-stack") == 0) |
| { |
| this->uses_split_stack_ = true; |
| return true; |
| } |
| if (strcmp(name, ".note.GNU-no-split-stack") == 0) |
| { |
| this->has_no_split_stack_ = true; |
| return true; |
| } |
| return false; |
| } |
| |
| // Class Relobj |
| |
| template<int size> |
| void |
| Relobj::initialize_input_to_output_map(unsigned int shndx, |
| typename elfcpp::Elf_types<size>::Elf_Addr starting_address, |
| Unordered_map<section_offset_type, |
| typename elfcpp::Elf_types<size>::Elf_Addr>* output_addresses) const { |
| Object_merge_map *map = this->object_merge_map_; |
| map->initialize_input_to_output_map<size>(shndx, starting_address, |
| output_addresses); |
| } |
| |
| void |
| Relobj::add_merge_mapping(Output_section_data *output_data, |
| unsigned int shndx, section_offset_type offset, |
| section_size_type length, |
| section_offset_type output_offset) { |
| Object_merge_map* object_merge_map = this->get_or_create_merge_map(); |
| object_merge_map->add_mapping(output_data, shndx, offset, length, output_offset); |
| } |
| |
| bool |
| Relobj::merge_output_offset(unsigned int shndx, section_offset_type offset, |
| section_offset_type *poutput) const { |
| Object_merge_map* object_merge_map = this->object_merge_map_; |
| if (object_merge_map == NULL) |
| return false; |
| return object_merge_map->get_output_offset(shndx, offset, poutput); |
| } |
| |
| const Output_section_data* |
| Relobj::find_merge_section(unsigned int shndx) const { |
| Object_merge_map* object_merge_map = this->object_merge_map_; |
| if (object_merge_map == NULL) |
| return NULL; |
| return object_merge_map->find_merge_section(shndx); |
| } |
| |
| // To copy the symbols data read from the file to a local data structure. |
| // This function is called from do_layout only while doing garbage |
| // collection. |
| |
| void |
| Relobj::copy_symbols_data(Symbols_data* gc_sd, Read_symbols_data* sd, |
| unsigned int section_header_size) |
| { |
| gc_sd->section_headers_data = |
| new unsigned char[(section_header_size)]; |
| memcpy(gc_sd->section_headers_data, sd->section_headers->data(), |
| section_header_size); |
| gc_sd->section_names_data = |
| new unsigned char[sd->section_names_size]; |
| memcpy(gc_sd->section_names_data, sd->section_names->data(), |
| sd->section_names_size); |
| gc_sd->section_names_size = sd->section_names_size; |
| if (sd->symbols != NULL) |
| { |
| gc_sd->symbols_data = |
| new unsigned char[sd->symbols_size]; |
| memcpy(gc_sd->symbols_data, sd->symbols->data(), |
| sd->symbols_size); |
| } |
| else |
| { |
| gc_sd->symbols_data = NULL; |
| } |
| gc_sd->symbols_size = sd->symbols_size; |
| gc_sd->external_symbols_offset = sd->external_symbols_offset; |
| if (sd->symbol_names != NULL) |
| { |
| gc_sd->symbol_names_data = |
| new unsigned char[sd->symbol_names_size]; |
| memcpy(gc_sd->symbol_names_data, sd->symbol_names->data(), |
| sd->symbol_names_size); |
| } |
| else |
| { |
| gc_sd->symbol_names_data = NULL; |
| } |
| gc_sd->symbol_names_size = sd->symbol_names_size; |
| } |
| |
| // This function determines if a particular section name must be included |
| // in the link. This is used during garbage collection to determine the |
| // roots of the worklist. |
| |
| bool |
| Relobj::is_section_name_included(const char* name) |
| { |
| if (is_prefix_of(".ctors", name) |
| || is_prefix_of(".dtors", name) |
| || is_prefix_of(".note", name) |
| || is_prefix_of(".init", name) |
| || is_prefix_of(".fini", name) |
| || is_prefix_of(".gcc_except_table", name) |
| || is_prefix_of(".jcr", name) |
| || is_prefix_of(".preinit_array", name) |
| || (is_prefix_of(".text", name) |
| && strstr(name, "personality")) |
| || (is_prefix_of(".data", name) |
| && strstr(name, "personality")) |
| || (is_prefix_of(".sdata", name) |
| && strstr(name, "personality")) |
| || (is_prefix_of(".gnu.linkonce.d", name) |
| && strstr(name, "personality")) |
| || (is_prefix_of(".rodata", name) |
| && strstr(name, "nptl_version"))) |
| { |
| return true; |
| } |
| return false; |
| } |
| |
| // Finalize the incremental relocation information. Allocates a block |
| // of relocation entries for each symbol, and sets the reloc_bases_ |
| // array to point to the first entry in each block. If CLEAR_COUNTS |
| // is TRUE, also clear the per-symbol relocation counters. |
| |
| void |
| Relobj::finalize_incremental_relocs(Layout* layout, bool clear_counts) |
| { |
| unsigned int nsyms = this->get_global_symbols()->size(); |
| this->reloc_bases_ = new unsigned int[nsyms]; |
| |
| gold_assert(this->reloc_bases_ != NULL); |
| gold_assert(layout->incremental_inputs() != NULL); |
| |
| unsigned int rindex = layout->incremental_inputs()->get_reloc_count(); |
| for (unsigned int i = 0; i < nsyms; ++i) |
| { |
| this->reloc_bases_[i] = rindex; |
| rindex += this->reloc_counts_[i]; |
| if (clear_counts) |
| this->reloc_counts_[i] = 0; |
| } |
| layout->incremental_inputs()->set_reloc_count(rindex); |
| } |
| |
| Object_merge_map* |
| Relobj::get_or_create_merge_map() |
| { |
| if (!this->object_merge_map_) |
| this->object_merge_map_ = new Object_merge_map(); |
| return this->object_merge_map_; |
| } |
| |
| // Class Sized_relobj. |
| |
| // Iterate over local symbols, calling a visitor class V for each GOT offset |
| // associated with a local symbol. |
| |
| template<int size, bool big_endian> |
| void |
| Sized_relobj<size, big_endian>::do_for_all_local_got_entries( |
| Got_offset_list::Visitor* v) const |
| { |
| unsigned int nsyms = this->local_symbol_count(); |
| for (unsigned int i = 0; i < nsyms; i++) |
| { |
| Local_got_entry_key key(i); |
| Local_got_offsets::const_iterator p = this->local_got_offsets_.find(key); |
| if (p != this->local_got_offsets_.end()) |
| { |
| const Got_offset_list* got_offsets = p->second; |
| got_offsets->for_all_got_offsets(v); |
| } |
| } |
| } |
| |
| // Get the address of an output section. |
| |
| template<int size, bool big_endian> |
| uint64_t |
| Sized_relobj<size, big_endian>::do_output_section_address( |
| unsigned int shndx) |
| { |
| // If the input file is linked as --just-symbols, the output |
| // section address is the input section address. |
| if (this->just_symbols()) |
| return this->section_address(shndx); |
| |
| const Output_section* os = this->do_output_section(shndx); |
| gold_assert(os != NULL); |
| return os->address(); |
| } |
| |
| // Class Sized_relobj_file. |
| |
| template<int size, bool big_endian> |
| Sized_relobj_file<size, big_endian>::Sized_relobj_file( |
| const std::string& name, |
| Input_file* input_file, |
| off_t offset, |
| const elfcpp::Ehdr<size, big_endian>& ehdr) |
| : Sized_relobj<size, big_endian>(name, input_file, offset), |
| elf_file_(this, ehdr), |
| osabi_(ehdr.get_ei_osabi()), |
| e_type_(ehdr.get_e_type()), |
| symtab_shndx_(-1U), |
| local_symbol_count_(0), |
| output_local_symbol_count_(0), |
| output_local_dynsym_count_(0), |
| symbols_(), |
| defined_count_(0), |
| local_symbol_offset_(0), |
| local_dynsym_offset_(0), |
| local_values_(), |
| local_plt_offsets_(), |
| kept_comdat_sections_(), |
| has_eh_frame_(false), |
| is_deferred_layout_(false), |
| deferred_layout_(), |
| deferred_layout_relocs_(), |
| output_views_(NULL) |
| { |
| } |
| |
| template<int size, bool big_endian> |
| Sized_relobj_file<size, big_endian>::~Sized_relobj_file() |
| { |
| } |
| |
| // Set up an object file based on the file header. This sets up the |
| // section information. |
| |
| template<int size, bool big_endian> |
| void |
| Sized_relobj_file<size, big_endian>::do_setup() |
| { |
| const unsigned int shnum = this->elf_file_.shnum(); |
| this->set_shnum(shnum); |
| } |
| |
| // Find the SHT_SYMTAB section, given the section headers. The ELF |
| // standard says that maybe in the future there can be more than one |
| // SHT_SYMTAB section. Until somebody figures out how that could |
| // work, we assume there is only one. |
| |
| template<int size, bool big_endian> |
| void |
| Sized_relobj_file<size, big_endian>::find_symtab(const unsigned char* pshdrs) |
| { |
| const unsigned int shnum = this->shnum(); |
| this->symtab_shndx_ = 0; |
| if (shnum > 0) |
| { |
| // Look through the sections in reverse order, since gas tends |
| // to put the symbol table at the end. |
| const unsigned char* p = pshdrs + shnum * This::shdr_size; |
| unsigned int i = shnum; |
| unsigned int xindex_shndx = 0; |
| unsigned int xindex_link = 0; |
| while (i > 0) |
| { |
| --i; |
| p -= This::shdr_size; |
| typename This::Shdr shdr(p); |
| if (shdr.get_sh_type() == elfcpp::SHT_SYMTAB) |
| { |
| this->symtab_shndx_ = i; |
| if (xindex_shndx > 0 && xindex_link == i) |
| { |
| Xindex* xindex = |
| new Xindex(this->elf_file_.large_shndx_offset()); |
| xindex->read_symtab_xindex<size, big_endian>(this, |
| xindex_shndx, |
| pshdrs); |
| this->set_xindex(xindex); |
| } |
| break; |
| } |
| |
| // Try to pick up the SHT_SYMTAB_SHNDX section, if there is |
| // one. This will work if it follows the SHT_SYMTAB |
| // section. |
| if (shdr.get_sh_type() == elfcpp::SHT_SYMTAB_SHNDX) |
| { |
| xindex_shndx = i; |
| xindex_link = this->adjust_shndx(shdr.get_sh_link()); |
| } |
| } |
| } |
| } |
| |
| // Return the Xindex structure to use for object with lots of |
| // sections. |
| |
| template<int size, bool big_endian> |
| Xindex* |
| Sized_relobj_file<size, big_endian>::do_initialize_xindex() |
| { |
| gold_assert(this->symtab_shndx_ != -1U); |
| Xindex* xindex = new Xindex(this->elf_file_.large_shndx_offset()); |
| xindex->initialize_symtab_xindex<size, big_endian>(this, this->symtab_shndx_); |
| return xindex; |
| } |
| |
| // Return whether SHDR has the right type and flags to be a GNU |
| // .eh_frame section. |
| |
| template<int size, bool big_endian> |
| bool |
| Sized_relobj_file<size, big_endian>::check_eh_frame_flags( |
| const elfcpp::Shdr<size, big_endian>* shdr) const |
| { |
| elfcpp::Elf_Word sh_type = shdr->get_sh_type(); |
| return ((sh_type == elfcpp::SHT_PROGBITS |
| || sh_type == parameters->target().unwind_section_type()) |
| && (shdr->get_sh_flags() & elfcpp::SHF_ALLOC) != 0); |
| } |
| |
| // Find the section header with the given name. |
| |
| template<int size, bool big_endian> |
| const unsigned char* |
| Object::find_shdr( |
| const unsigned char* pshdrs, |
| const char* name, |
| const char* names, |
| section_size_type names_size, |
| const unsigned char* hdr) const |
| { |
| const int shdr_size = elfcpp::Elf_sizes<size>::shdr_size; |
| const unsigned int shnum = this->shnum(); |
| const unsigned char* hdr_end = pshdrs + shdr_size * shnum; |
| size_t sh_name = 0; |
| |
| while (1) |
| { |
| if (hdr) |
| { |
| // We found HDR last time we were called, continue looking. |
| typename elfcpp::Shdr<size, big_endian> shdr(hdr); |
| sh_name = shdr.get_sh_name(); |
| } |
| else |
| { |
| // Look for the next occurrence of NAME in NAMES. |
| // The fact that .shstrtab produced by current GNU tools is |
| // string merged means we shouldn't have both .not.foo and |
| // .foo in .shstrtab, and multiple .foo sections should all |
| // have the same sh_name. However, this is not guaranteed |
| // by the ELF spec and not all ELF object file producers may |
| // be so clever. |
| size_t len = strlen(name) + 1; |
| const char *p = sh_name ? names + sh_name + len : names; |
| p = reinterpret_cast<const char*>(memmem(p, names_size - (p - names), |
| name, len)); |
| if (p == NULL) |
| return NULL; |
| sh_name = p - names; |
| hdr = pshdrs; |
| if (sh_name == 0) |
| return hdr; |
| } |
| |
| hdr += shdr_size; |
| while (hdr < hdr_end) |
| { |
| typename elfcpp::Shdr<size, big_endian> shdr(hdr); |
| if (shdr.get_sh_name() == sh_name) |
| return hdr; |
| hdr += shdr_size; |
| } |
| hdr = NULL; |
| if (sh_name == 0) |
| return hdr; |
| } |
| } |
| |
| // Return whether there is a GNU .eh_frame section, given the section |
| // headers and the section names. |
| |
| template<int size, bool big_endian> |
| bool |
| Sized_relobj_file<size, big_endian>::find_eh_frame( |
| const unsigned char* pshdrs, |
| const char* names, |
| section_size_type names_size) const |
| { |
| const unsigned char* s = NULL; |
| |
| while (1) |
| { |
| s = this->template find_shdr<size, big_endian>(pshdrs, ".eh_frame", |
| names, names_size, s); |
| if (s == NULL) |
| return false; |
| |
| typename This::Shdr shdr(s); |
| if (this->check_eh_frame_flags(&shdr)) |
| return true; |
| } |
| } |
| |
| // Return TRUE if this is a section whose contents will be needed in the |
| // Add_symbols task. This function is only called for sections that have |
| // already passed the test in is_compressed_debug_section() and the debug |
| // section name prefix, ".debug"/".zdebug", has been skipped. |
| |
| static bool |
| need_decompressed_section(const char* name) |
| { |
| if (*name++ != '_') |
| return false; |
| |
| #ifdef ENABLE_THREADS |
| // Decompressing these sections now will help only if we're |
| // multithreaded. |
| if (parameters->options().threads()) |
| { |
| // We will need .zdebug_str if this is not an incremental link |
| // (i.e., we are processing string merge sections) or if we need |
| // to build a gdb index. |
| if ((!parameters->incremental() || parameters->options().gdb_index()) |
| && strcmp(name, "str") == 0) |
| return true; |
| |
| // We will need these other sections when building a gdb index. |
| if (parameters->options().gdb_index() |
| && (strcmp(name, "info") == 0 |
| || strcmp(name, "types") == 0 |
| || strcmp(name, "pubnames") == 0 |
| || strcmp(name, "pubtypes") == 0 |
| || strcmp(name, "ranges") == 0 |
| || strcmp(name, "abbrev") == 0)) |
| return true; |
| } |
| #endif |
| |
| // Even when single-threaded, we will need .zdebug_str if this is |
| // not an incremental link and we are building a gdb index. |
| // Otherwise, we would decompress the section twice: once for |
| // string merge processing, and once for building the gdb index. |
| if (!parameters->incremental() |
| && parameters->options().gdb_index() |
| && strcmp(name, "str") == 0) |
| return true; |
| |
| return false; |
| } |
| |
| // Build a table for any compressed debug sections, mapping each section index |
| // to the uncompressed size and (if needed) the decompressed contents. |
| |
| template<int size, bool big_endian> |
| Compressed_section_map* |
| build_compressed_section_map( |
| const unsigned char* pshdrs, |
| unsigned int shnum, |
| const char* names, |
| section_size_type names_size, |
| Object* obj, |
| bool decompress_if_needed) |
| { |
| Compressed_section_map* uncompressed_map = new Compressed_section_map(); |
| const unsigned int shdr_size = elfcpp::Elf_sizes<size>::shdr_size; |
| const unsigned char* p = pshdrs + shdr_size; |
| |
| for (unsigned int i = 1; i < shnum; ++i, p += shdr_size) |
| { |
| typename elfcpp::Shdr<size, big_endian> shdr(p); |
| if (shdr.get_sh_type() == elfcpp::SHT_PROGBITS |
| && (shdr.get_sh_flags() & elfcpp::SHF_ALLOC) == 0) |
| { |
| if (shdr.get_sh_name() >= names_size) |
| { |
| obj->error(_("bad section name offset for section %u: %lu"), |
| i, static_cast<unsigned long>(shdr.get_sh_name())); |
| continue; |
| } |
| |
| const char* name = names + shdr.get_sh_name(); |
| bool is_compressed = ((shdr.get_sh_flags() |
| & elfcpp::SHF_COMPRESSED) != 0); |
| bool is_zcompressed = (!is_compressed |
| && is_compressed_debug_section(name)); |
| |
| if (is_zcompressed || is_compressed) |
| { |
| section_size_type len; |
| const unsigned char* contents = |
| obj->section_contents(i, &len, false); |
| uint64_t uncompressed_size; |
| Compressed_section_info info; |
| if (is_zcompressed) |
| { |
| // Skip over the ".zdebug" prefix. |
| name += 7; |
| uncompressed_size = get_uncompressed_size(contents, len); |
| info.addralign = shdr.get_sh_addralign(); |
| } |
| else |
| { |
| // Skip over the ".debug" prefix. |
| name += 6; |
| elfcpp::Chdr<size, big_endian> chdr(contents); |
| uncompressed_size = chdr.get_ch_size(); |
| info.addralign = chdr.get_ch_addralign(); |
| } |
| info.size = convert_to_section_size_type(uncompressed_size); |
| info.flag = shdr.get_sh_flags(); |
| info.contents = NULL; |
| if (uncompressed_size != -1ULL) |
| { |
| unsigned char* uncompressed_data = NULL; |
| if (decompress_if_needed && need_decompressed_section(name)) |
| { |
| uncompressed_data = new unsigned char[uncompressed_size]; |
| if (decompress_input_section(contents, len, |
| uncompressed_data, |
| uncompressed_size, |
| size, big_endian, |
| shdr.get_sh_flags())) |
| info.contents = uncompressed_data; |
| else |
| delete[] uncompressed_data; |
| } |
| (*uncompressed_map)[i] = info; |
| } |
| } |
| } |
| } |
| return uncompressed_map; |
| } |
| |
| // Stash away info for a number of special sections. |
| // Return true if any of the sections found require local symbols to be read. |
| |
| template<int size, bool big_endian> |
| bool |
| Sized_relobj_file<size, big_endian>::do_find_special_sections( |
| Read_symbols_data* sd) |
| { |
| const unsigned char* const pshdrs = sd->section_headers->data(); |
| const unsigned char* namesu = sd->section_names->data(); |
| const char* names = reinterpret_cast<const char*>(namesu); |
| |
| if (this->find_eh_frame(pshdrs, names, sd->section_names_size)) |
| this->has_eh_frame_ = true; |
| |
| Compressed_section_map* compressed_sections = |
| build_compressed_section_map<size, big_endian>( |
| pshdrs, this->shnum(), names, sd->section_names_size, this, true); |
| if (compressed_sections != NULL) |
| this->set_compressed_sections(compressed_sections); |
| |
| return (this->has_eh_frame_ |
| || (!parameters->options().relocatable() |
| && parameters->options().gdb_index() |
| && (memmem(names, sd->section_names_size, "debug_info", 11) != NULL |
| || memmem(names, sd->section_names_size, |
| "debug_types", 12) != NULL))); |
| } |
| |
| // Read the sections and symbols from an object file. |
| |
| template<int size, bool big_endian> |
| void |
| Sized_relobj_file<size, big_endian>::do_read_symbols(Read_symbols_data* sd) |
| { |
| this->base_read_symbols(sd); |
| } |
| |
| // Read the sections and symbols from an object file. This is common |
| // code for all target-specific overrides of do_read_symbols(). |
| |
| template<int size, bool big_endian> |
| void |
| Sized_relobj_file<size, big_endian>::base_read_symbols(Read_symbols_data* sd) |
| { |
| this->read_section_data(&this->elf_file_, sd); |
| |
| const unsigned char* const pshdrs = sd->section_headers->data(); |
| |
| this->find_symtab(pshdrs); |
| |
| bool need_local_symbols = this->do_find_special_sections(sd); |
| |
| sd->symbols = NULL; |
| sd->symbols_size = 0; |
| sd->external_symbols_offset = 0; |
| sd->symbol_names = NULL; |
| sd->symbol_names_size = 0; |
| |
| if (this->symtab_shndx_ == 0) |
| { |
| // No symbol table. Weird but legal. |
| return; |
| } |
| |
| // Get the symbol table section header. |
| typename This::Shdr symtabshdr(pshdrs |
| + this->symtab_shndx_ * This::shdr_size); |
| gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB); |
| |
| // If this object has a .eh_frame section, or if building a .gdb_index |
| // section and there is debug info, we need all the symbols. |
| // Otherwise we only need the external symbols. While it would be |
| // simpler to just always read all the symbols, I've seen object |
| // files with well over 2000 local symbols, which for a 64-bit |
| // object file format is over 5 pages that we don't need to read |
| // now. |
| |
| const int sym_size = This::sym_size; |
| const unsigned int loccount = symtabshdr.get_sh_info(); |
| this->local_symbol_count_ = loccount; |
| this->local_values_.resize(loccount); |
| section_offset_type locsize = loccount * sym_size; |
| off_t dataoff = symtabshdr.get_sh_offset(); |
| section_size_type datasize = |
| convert_to_section_size_type(symtabshdr.get_sh_size()); |
| off_t extoff = dataoff + locsize; |
| section_size_type extsize = datasize - locsize; |
| |
| off_t readoff = need_local_symbols ? dataoff : extoff; |
| section_size_type readsize = need_local_symbols ? datasize : extsize; |
| |
| if (readsize == 0) |
| { |
| // No external symbols. Also weird but also legal. |
| return; |
| } |
| |
| File_view* fvsymtab = this->get_lasting_view(readoff, readsize, true, false); |
| |
| // Read the section header for the symbol names. |
| unsigned int strtab_shndx = this->adjust_shndx(symtabshdr.get_sh_link()); |
| if (strtab_shndx >= this->shnum()) |
| { |
| this->error(_("invalid symbol table name index: %u"), strtab_shndx); |
| return; |
| } |
| typename This::Shdr strtabshdr(pshdrs + strtab_shndx * This::shdr_size); |
| if (strtabshdr.get_sh_type() != elfcpp::SHT_STRTAB) |
| { |
| this->error(_("symbol table name section has wrong type: %u"), |
| static_cast<unsigned int>(strtabshdr.get_sh_type())); |
| return; |
| } |
| |
| // Read the symbol names. |
| File_view* fvstrtab = this->get_lasting_view(strtabshdr.get_sh_offset(), |
| strtabshdr.get_sh_size(), |
| false, true); |
| |
| sd->symbols = fvsymtab; |
| sd->symbols_size = readsize; |
| sd->external_symbols_offset = need_local_symbols ? locsize : 0; |
| sd->symbol_names = fvstrtab; |
| sd->symbol_names_size = |
| convert_to_section_size_type(strtabshdr.get_sh_size()); |
| } |
| |
| // Return the section index of symbol SYM. Set *VALUE to its value in |
| // the object file. Set *IS_ORDINARY if this is an ordinary section |
| // index, not a special code between SHN_LORESERVE and SHN_HIRESERVE. |
| // Note that for a symbol which is not defined in this object file, |
| // this will set *VALUE to 0 and return SHN_UNDEF; it will not return |
| // the final value of the symbol in the link. |
| |
| template<int size, bool big_endian> |
| unsigned int |
| Sized_relobj_file<size, big_endian>::symbol_section_and_value(unsigned int sym, |
| Address* value, |
| bool* is_ordinary) |
| { |
| section_size_type symbols_size; |
| const unsigned char* symbols = this->section_contents(this->symtab_shndx_, |
| &symbols_size, |
| false); |
| |
| const size_t count = symbols_size / This::sym_size; |
| gold_assert(sym < count); |
| |
| elfcpp::Sym<size, big_endian> elfsym(symbols + sym * This::sym_size); |
| *value = elfsym.get_st_value(); |
| |
| return this->adjust_sym_shndx(sym, elfsym.get_st_shndx(), is_ordinary); |
| } |
| |
| // Return whether to include a section group in the link. LAYOUT is |
| // used to keep track of which section groups we have already seen. |
| // INDEX is the index of the section group and SHDR is the section |
| // header. If we do not want to include this group, we set bits in |
| // OMIT for each section which should be discarded. |
| |
| template<int size, bool big_endian> |
| bool |
| Sized_relobj_file<size, big_endian>::include_section_group( |
| Symbol_table* symtab, |
| Layout* layout, |
| unsigned int index, |
| const char* name, |
| const unsigned char* shdrs, |
| const char* section_names, |
| section_size_type section_names_size, |
| std::vector<bool>* omit) |
| { |
| // Read the section contents. |
| typename This::Shdr shdr(shdrs + index * This::shdr_size); |
| const unsigned char* pcon = this->get_view(shdr.get_sh_offset(), |
| shdr.get_sh_size(), true, false); |
| const elfcpp::Elf_Word* pword = |
| reinterpret_cast<const elfcpp::Elf_Word*>(pcon); |
| |
| // The first word contains flags. We only care about COMDAT section |
| // groups. Other section groups are always included in the link |
| // just like ordinary sections. |
| elfcpp::Elf_Word flags = elfcpp::Swap<32, big_endian>::readval(pword); |
| |
| // Look up the group signature, which is the name of a symbol. ELF |
| // uses a symbol name because some group signatures are long, and |
| // the name is generally already in the symbol table, so it makes |
| // sense to put the long string just once in .strtab rather than in |
| // both .strtab and .shstrtab. |
| |
| // Get the appropriate symbol table header (this will normally be |
| // the single SHT_SYMTAB section, but in principle it need not be). |
| const unsigned int link = this->adjust_shndx(shdr.get_sh_link()); |
| typename This::Shdr symshdr(this, this->elf_file_.section_header(link)); |
| |
| // Read the symbol table entry. |
| unsigned int symndx = shdr.get_sh_info(); |
| if (symndx >= symshdr.get_sh_size() / This::sym_size) |
| { |
| this->error(_("section group %u info %u out of range"), |
| index, symndx); |
| return false; |
| } |
| off_t symoff = symshdr.get_sh_offset() + symndx * This::sym_size; |
| const unsigned char* psym = this->get_view(symoff, This::sym_size, true, |
| false); |
| elfcpp::Sym<size, big_endian> sym(psym); |
| |
| // Read the symbol table names. |
| section_size_type symnamelen; |
| const unsigned char* psymnamesu; |
| psymnamesu = this->section_contents(this->adjust_shndx(symshdr.get_sh_link()), |
| &symnamelen, true); |
| const char* psymnames = reinterpret_cast<const char*>(psymnamesu); |
| |
| // Get the section group signature. |
| if (sym.get_st_name() >= symnamelen) |
| { |
| this->error(_("symbol %u name offset %u out of range"), |
| symndx, sym.get_st_name()); |
| return false; |
| } |
| |
| std::string signature(psymnames + sym.get_st_name()); |
| |
| // It seems that some versions of gas will create a section group |
| // associated with a section symbol, and then fail to give a name to |
| // the section symbol. In such a case, use the name of the section. |
| if (signature[0] == '\0' && sym.get_st_type() == elfcpp::STT_SECTION) |
| { |
| bool is_ordinary; |
| unsigned int sym_shndx = this->adjust_sym_shndx(symndx, |
| sym.get_st_shndx(), |
| &is_ordinary); |
| if (!is_ordinary || sym_shndx >= this->shnum()) |
| { |
| this->error(_("symbol %u invalid section index %u"), |
| symndx, sym_shndx); |
| return false; |
| } |
| typename This::Shdr member_shdr(shdrs + sym_shndx * This::shdr_size); |
| if (member_shdr.get_sh_name() < section_names_size) |
| signature = section_names + member_shdr.get_sh_name(); |
| } |
| |
| // Record this section group in the layout, and see whether we've already |
| // seen one with the same signature. |
| bool include_group; |
| bool is_comdat; |
| Kept_section* kept_section = NULL; |
| |
| if ((flags & elfcpp::GRP_COMDAT) == 0) |
| { |
| include_group = true; |
| is_comdat = false; |
| } |
| else |
| { |
| include_group = layout->find_or_add_kept_section(signature, |
| this, index, true, |
| true, &kept_section); |
| is_comdat = true; |
| } |
| |
| if (is_comdat && include_group) |
| { |
| Incremental_inputs* incremental_inputs = layout->incremental_inputs(); |
| if (incremental_inputs != NULL) |
| incremental_inputs->report_comdat_group(this, signature.c_str()); |
| } |
| |
| size_t count = shdr.get_sh_size() / sizeof(elfcpp::Elf_Word); |
| |
| std::vector<unsigned int> shndxes; |
| bool relocate_group = include_group && parameters->options().relocatable(); |
| if (relocate_group) |
| shndxes.reserve(count - 1); |
| |
| for (size_t i = 1; i < count; ++i) |
| { |
| elfcpp::Elf_Word shndx = |
| this->adjust_shndx(elfcpp::Swap<32, big_endian>::readval(pword + i)); |
| |
| if (relocate_group) |
| shndxes.push_back(shndx); |
| |
| if (shndx >= this->shnum()) |
| { |
| this->error(_("section %u in section group %u out of range"), |
| shndx, index); |
| continue; |
| } |
| |
| // Check for an earlier section number, since we're going to get |
| // it wrong--we may have already decided to include the section. |
| if (shndx < index) |
| this->error(_("invalid section group %u refers to earlier section %u"), |
| index, shndx); |
| |
| // Get the name of the member section. |
| typename This::Shdr member_shdr(shdrs + shndx * This::shdr_size); |
| if (member_shdr.get_sh_name() >= section_names_size) |
| { |
| // This is an error, but it will be diagnosed eventually |
| // in do_layout, so we don't need to do anything here but |
| // ignore it. |
| continue; |
| } |
| std::string mname(section_names + member_shdr.get_sh_name()); |
| |
| if (include_group) |
| { |
| if (is_comdat) |
| kept_section->add_comdat_section(mname, shndx, |
| member_shdr.get_sh_size()); |
| } |
| else |
| { |
| (*omit)[shndx] = true; |
| |
| // Store a mapping from this section to the Kept_section |
| // information for the group. This mapping is used for |
| // relocation processing and diagnostics. |
| // If the kept section is a linkonce section, we don't |
| // bother with it unless the comdat group contains just |
| // a single section, making it easy to match up. |
| if (is_comdat |
| && (kept_section->is_comdat() || count == 2)) |
| this->set_kept_comdat_section(shndx, true, symndx, |
| member_shdr.get_sh_size(), |
| kept_section); |
| } |
| } |
| |
| if (relocate_group) |
| layout->layout_group(symtab, this, index, name, signature.c_str(), |
| shdr, flags, &shndxes); |
| |
| return include_group; |
| } |
| |
| // Whether to include a linkonce section in the link. NAME is the |
| // name of the section and SHDR is the section header. |
| |
| // Linkonce sections are a GNU extension implemented in the original |
| // GNU linker before section groups were defined. The semantics are |
| // that we only include one linkonce section with a given name. The |
| // name of a linkonce section is normally .gnu.linkonce.T.SYMNAME, |
| // where T is the type of section and SYMNAME is the name of a symbol. |
| // In an attempt to make linkonce sections interact well with section |
| // groups, we try to identify SYMNAME and use it like a section group |
| // signature. We want to block section groups with that signature, |
| // but not other linkonce sections with that signature. We also use |
| // the full name of the linkonce section as a normal section group |
| // signature. |
| |
| template<int size, bool big_endian> |
| bool |
| Sized_relobj_file<size, big_endian>::include_linkonce_section( |
| Layout* layout, |
| unsigned int index, |
| const char* name, |
| const elfcpp::Shdr<size, big_endian>& shdr) |
| { |
| typename elfcpp::Elf_types<size>::Elf_WXword sh_size = shdr.get_sh_size(); |
| // In general the symbol name we want will be the string following |
| // the last '.'. However, we have to handle the case of |
| // .gnu.linkonce.t.__i686.get_pc_thunk.bx, which was generated by |
| // some versions of gcc. So we use a heuristic: if the name starts |
| // with ".gnu.linkonce.t.", we use everything after that. Otherwise |
| // we look for the last '.'. We can't always simply skip |
| // ".gnu.linkonce.X", because we have to deal with cases like |
| // ".gnu.linkonce.d.rel.ro.local". |
| const char* const linkonce_t = ".gnu.linkonce.t."; |
| const char* symname; |
| if (strncmp(name, linkonce_t, strlen(linkonce_t)) == 0) |
| symname = name + strlen(linkonce_t); |
| else |
| symname = strrchr(name, '.') + 1; |
| std::string sig1(symname); |
| std::string sig2(name); |
| Kept_section* kept1; |
| Kept_section* kept2; |
| bool include1 = layout->find_or_add_kept_section(sig1, this, index, false, |
| false, &kept1); |
| bool include2 = layout->find_or_add_kept_section(sig2, this, index, false, |
| true, &kept2); |
| |
| if (!include2) |
| { |
| // We are not including this section because we already saw the |
| // name of the section as a signature. This normally implies |
| // that the kept section is another linkonce section. If it is |
| // the same size, record it as the section which corresponds to |
| // this one. |
| if (kept2->object() != NULL && !kept2->is_comdat()) |
| this->set_kept_comdat_section(index, false, 0, sh_size, kept2); |
| } |
| else if (!include1) |
| { |
| // The section is being discarded on the basis of its symbol |
| // name. This means that the corresponding kept section was |
| // part of a comdat group, and it will be difficult to identify |
| // the specific section within that group that corresponds to |
| // this linkonce section. We'll handle the simple case where |
| // the group has only one member section. Otherwise, it's not |
| // worth the effort. |
| if (kept1->object() != NULL && kept1->is_comdat()) |
| this->set_kept_comdat_section(index, false, 0, sh_size, kept1); |
| } |
| else |
| { |
| kept1->set_linkonce_size(sh_size); |
| kept2->set_linkonce_size(sh_size); |
| } |
| |
| return include1 && include2; |
| } |
| |
| // Layout an input section. |
| |
| template<int size, bool big_endian> |
| inline void |
| Sized_relobj_file<size, big_endian>::layout_section( |
| Layout* layout, |
| unsigned int shndx, |
| const char* name, |
| const typename This::Shdr& shdr, |
| unsigned int sh_type, |
| unsigned int reloc_shndx, |
| unsigned int reloc_type) |
| { |
| off_t offset; |
| Output_section* os = layout->layout(this, shndx, name, shdr, sh_type, |
| reloc_shndx, reloc_type, &offset); |
| |
| this->output_sections()[shndx] = os; |
| if (offset == -1) |
| this->section_offsets()[shndx] = invalid_address; |
| else |
| this->section_offsets()[shndx] = convert_types<Address, off_t>(offset); |
| |
| // If this section requires special handling, and if there are |
| // relocs that apply to it, then we must do the special handling |
| // before we apply the relocs. |
| if (offset == -1 && reloc_shndx != 0) |
| this->set_relocs_must_follow_section_writes(); |
| } |
| |
| // Layout an input .eh_frame section. |
| |
| template<int size, bool big_endian> |
| void |
| Sized_relobj_file<size, big_endian>::layout_eh_frame_section( |
| Layout* layout, |
| const unsigned char* symbols_data, |
| section_size_type symbols_size, |
| const unsigned char* symbol_names_data, |
| section_size_type symbol_names_size, |
| unsigned int shndx, |
| const typename This::Shdr& shdr, |
| unsigned int reloc_shndx, |
| unsigned int reloc_type) |
| { |
| gold_assert(this->has_eh_frame_); |
| |
| off_t offset; |
| Output_section* os = layout->layout_eh_frame(this, |
| symbols_data, |
| symbols_size, |
| symbol_names_data, |
| symbol_names_size, |
| shndx, |
| shdr, |
| reloc_shndx, |
| reloc_type, |
| &offset); |
| this->output_sections()[shndx] = os; |
| if (os == NULL || offset == -1) |
| this->section_offsets()[shndx] = invalid_address; |
| else |
| this->section_offsets()[shndx] = convert_types<Address, off_t>(offset); |
| |
| // If this section requires special handling, and if there are |
| // relocs that aply to it, then we must do the special handling |
| // before we apply the relocs. |
| if (os != NULL && offset == -1 && reloc_shndx != 0) |
| this->set_relocs_must_follow_section_writes(); |
| } |
| |
| // Layout an input .note.gnu.property section. |
| |
| // This note section has an *extremely* non-standard layout. |
| // The gABI spec says that ELF-64 files should have 8-byte fields and |
| // 8-byte alignment in the note section, but the Gnu tools generally |
| // use 4-byte fields and 4-byte alignment (see the comment for |
| // Layout::create_note). This section uses 4-byte fields (i.e., |
| // namesz, descsz, and type are always 4 bytes), the name field is |
| // padded to a multiple of 4 bytes, but the desc field is padded |
| // to a multiple of 4 or 8 bytes, depending on the ELF class. |
| // The individual properties within the desc field always use |
| // 4-byte pr_type and pr_datasz fields, but pr_data is padded to |
| // a multiple of 4 or 8 bytes, depending on the ELF class. |
| |
| template<int size, bool big_endian> |
| void |
| Sized_relobj_file<size, big_endian>::layout_gnu_property_section( |
| Layout* layout, |
| unsigned int shndx) |
| { |
| // We ignore Gnu property sections on incremental links. |
| if (parameters->incremental()) |
| return; |
| |
| section_size_type contents_len; |
| const unsigned char* pcontents = this->section_contents(shndx, |
| &contents_len, |
| false); |
| const unsigned char* pcontents_end = pcontents + contents_len; |
| |
| // Loop over all the notes in this section. |
| while (pcontents < pcontents_end) |
| { |
| if (pcontents + 16 > pcontents_end) |
| { |
| gold_warning(_("%s: corrupt .note.gnu.property section " |
| "(note too short)"), |
| this->name().c_str()); |
| return; |
| } |
| |
| size_t namesz = elfcpp::Swap<32, big_endian>::readval(pcontents); |
| size_t descsz = elfcpp::Swap<32, big_endian>::readval(pcontents + 4); |
| unsigned int ntype = elfcpp::Swap<32, big_endian>::readval(pcontents + 8); |
| const unsigned char* pname = pcontents + 12; |
| |
| if (namesz != 4 || strcmp(reinterpret_cast<const char*>(pname), "GNU") != 0) |
| { |
| gold_warning(_("%s: corrupt .note.gnu.property section " |
| "(name is not 'GNU')"), |
| this->name().c_str()); |
| return; |
| } |
| |
| if (ntype != elfcpp::NT_GNU_PROPERTY_TYPE_0) |
| { |
| gold_warning(_("%s: unsupported note type %d " |
| "in .note.gnu.property section"), |
| this->name().c_str(), ntype); |
| return; |
| } |
| |
| size_t aligned_namesz = align_address(namesz, 4); |
| const unsigned char* pdesc = pname + aligned_namesz; |
| |
| if (pdesc + descsz > pcontents + contents_len) |
| { |
| gold_warning(_("%s: corrupt .note.gnu.property section"), |
| this->name().c_str()); |
| return; |
| } |
| |
| const unsigned char* pprop = pdesc; |
| |
| // Loop over the program properties in this note. |
| while (pprop < pdesc + descsz) |
| { |
| if (pprop + 8 > pdesc + descsz) |
| { |
| gold_warning(_("%s: corrupt .note.gnu.property section"), |
| this->name().c_str()); |
| return; |
| } |
| unsigned int pr_type = elfcpp::Swap<32, big_endian>::readval(pprop); |
| size_t pr_datasz = elfcpp::Swap<32, big_endian>::readval(pprop + 4); |
| pprop += 8; |
| if (pprop + pr_datasz > pdesc + descsz) |
| { |
| gold_warning(_("%s: corrupt .note.gnu.property section"), |
| this->name().c_str()); |
| return; |
| } |
| layout->layout_gnu_property(ntype, pr_type, pr_datasz, pprop, this); |
| pprop += align_address(pr_datasz, size / 8); |
| } |
| |
| pcontents = pdesc + align_address(descsz, size / 8); |
| } |
| } |
| |
| // This a copy of lto_section defined in GCC (lto-streamer.h) |
| |
| struct lto_section |
| { |
| int16_t major_version; |
| int16_t minor_version; |
| unsigned char slim_object; |
| |
| /* Flags is a private field that is not defined publicly. */ |
| uint16_t flags; |
| }; |
| |
| // Lay out the input sections. We walk through the sections and check |
| // whether they should be included in the link. If they should, we |
| // pass them to the Layout object, which will return an output section |
| // and an offset. |
| // This function is called twice sometimes, two passes, when mapping |
| // of input sections to output sections must be delayed. |
| // This is true for the following : |
| // * Garbage collection (--gc-sections): Some input sections will be |
| // discarded and hence the assignment must wait until the second pass. |
| // In the first pass, it is for setting up some sections as roots to |
| // a work-list for --gc-sections and to do comdat processing. |
| // * Identical Code Folding (--icf=<safe,all>): Some input sections |
| // will be folded and hence the assignment must wait. |
| // * Using plugins to map some sections to unique segments: Mapping |
| // some sections to unique segments requires mapping them to unique |
| // output sections too. This can be done via plugins now and this |
| // information is not available in the first pass. |
| |
| template<int size, bool big_endian> |
| void |
| Sized_relobj_file<size, big_endian>::do_layout(Symbol_table* symtab, |
| Layout* layout, |
| Read_symbols_data* sd) |
| { |
| const unsigned int unwind_section_type = |
| parameters->target().unwind_section_type(); |
| const unsigned int shnum = this->shnum(); |
| |
| /* Should this function be called twice? */ |
| bool is_two_pass = (parameters->options().gc_sections() |
| || parameters->options().icf_enabled() |
| || layout->is_unique_segment_for_sections_specified()); |
| |
| /* Only one of is_pass_one and is_pass_two is true. Both are false when |
| a two-pass approach is not needed. */ |
| bool is_pass_one = false; |
| bool is_pass_two = false; |
| |
| Symbols_data* gc_sd = NULL; |
| |
| /* Check if do_layout needs to be two-pass. If so, find out which pass |
| should happen. In the first pass, the data in sd is saved to be used |
| later in the second pass. */ |
| if (is_two_pass) |
| { |
| gc_sd = this->get_symbols_data(); |
| if (gc_sd == NULL) |
| { |
| gold_assert(sd != NULL); |
| is_pass_one = true; |
| } |
| else |
| { |
| if (parameters->options().gc_sections()) |
| gold_assert(symtab->gc()->is_worklist_ready()); |
| if (parameters->options().icf_enabled()) |
| gold_assert(symtab->icf()->is_icf_ready()); |
| is_pass_two = true; |
| } |
| } |
| |
| if (shnum == 0) |
| return; |
| |
| if (is_pass_one) |
| { |
| // During garbage collection save the symbols data to use it when |
| // re-entering this function. |
| gc_sd = new Symbols_data; |
| this->copy_symbols_data(gc_sd, sd, This::shdr_size * shnum); |
| this->set_symbols_data(gc_sd); |
| } |
| |
| const unsigned char* section_headers_data = NULL; |
| section_size_type section_names_size; |
| const unsigned char* symbols_data = NULL; |
| section_size_type symbols_size; |
| const unsigned char* symbol_names_data = NULL; |
| section_size_type symbol_names_size; |
| |
| if (is_two_pass) |
| { |
| section_headers_data = gc_sd->section_headers_data; |
| section_names_size = gc_sd->section_names_size; |
| symbols_data = gc_sd->symbols_data; |
| symbols_size = gc_sd->symbols_size; |
| symbol_names_data = gc_sd->symbol_names_data; |
| symbol_names_size = gc_sd->symbol_names_size; |
| } |
| else |
| { |
| section_headers_data = sd->section_headers->data(); |
| section_names_size = sd->section_names_size; |
| if (sd->symbols != NULL) |
| symbols_data = sd->symbols->data(); |
| symbols_size = sd->symbols_size; |
| if (sd->symbol_names != NULL) |
| symbol_names_data = sd->symbol_names->data(); |
| symbol_names_size = sd->symbol_names_size; |
| } |
| |
| // Get the section headers. |
| const unsigned char* shdrs = section_headers_data; |
| const unsigned char* pshdrs; |
| |
| // Get the section names. |
| const unsigned char* pnamesu = (is_two_pass |
| ? gc_sd->section_names_data |
| : sd->section_names->data()); |
| |
| const char* pnames = reinterpret_cast<const char*>(pnamesu); |
| |
| // If any input files have been claimed by plugins, we need to defer |
| // actual layout until the replacement files have arrived. |
| const bool should_defer_layout = |
| (parameters->options().has_plugins() |
| && parameters->options().plugins()->should_defer_layout()); |
| unsigned int num_sections_to_defer = 0; |
| |
| // For each section, record the index of the reloc section if any. |
| // Use 0 to mean that there is no reloc section, -1U to mean that |
| // there is more than one. |
| std::vector<unsigned int> reloc_shndx(shnum, 0); |
| std::vector<unsigned int> reloc_type(shnum, elfcpp::SHT_NULL); |
| // Skip the first, dummy, section. |
| pshdrs = shdrs + This::shdr_size; |
| for (unsigned int i = 1; i < shnum; ++i, pshdrs += This::shdr_size) |
| { |
| typename This::Shdr shdr(pshdrs); |
| |
| // Count the number of sections whose layout will be deferred. |
| if (should_defer_layout && (shdr.get_sh_flags() & elfcpp::SHF_ALLOC)) |
| ++num_sections_to_defer; |
| |
| unsigned int sh_type = shdr.get_sh_type(); |
| if (sh_type == elfcpp::SHT_REL || sh_type == elfcpp::SHT_RELA) |
| { |
| unsigned int target_shndx = this->adjust_shndx(shdr.get_sh_info()); |
| if (target_shndx == 0 || target_shndx >= shnum) |
| { |
| this->error(_("relocation section %u has bad info %u"), |
| i, target_shndx); |
| continue; |
| } |
| |
| if (reloc_shndx[target_shndx] != 0) |
| reloc_shndx[target_shndx] = -1U; |
| else |
| { |
| reloc_shndx[target_shndx] = i; |
| reloc_type[target_shndx] = sh_type; |
| } |
| } |
| } |
| |
| Output_sections& out_sections(this->output_sections()); |
| std::vector<Address>& out_section_offsets(this->section_offsets()); |
| |
| if (!is_pass_two) |
| { |
| out_sections.resize(shnum); |
| out_section_offsets.resize(shnum); |
| } |
| |
| // If we are only linking for symbols, then there is nothing else to |
| // do here. |
| if (this->input_file()->just_symbols()) |
| { |
| if (!is_pass_two) |
| { |
| delete sd->section_headers; |
| sd->section_headers = NULL; |
| delete sd->section_names; |
| sd->section_names = NULL; |
| } |
| return; |
| } |
| |
| if (num_sections_to_defer > 0) |
| { |
| parameters->options().plugins()->add_deferred_layout_object(this); |
| this->deferred_layout_.reserve(num_sections_to_defer); |
| this->is_deferred_layout_ = true; |
| } |
| |
| // Whether we've seen a .note.GNU-stack section. |
| bool seen_gnu_stack = false; |
| // The flags of a .note.GNU-stack section. |
| uint64_t gnu_stack_flags = 0; |
| |
| // Keep track of which sections to omit. |
| std::vector<bool> omit(shnum, false); |
| |
| // Keep track of reloc sections when emitting relocations. |
| const bool relocatable = parameters->options().relocatable(); |
| const bool emit_relocs = (relocatable |
| || parameters->options().emit_relocs()); |
| std::vector<unsigned int> reloc_sections; |
| |
| // Keep track of .eh_frame sections. |
| std::vector<unsigned int> eh_frame_sections; |
| |
| // Keep track of .debug_info and .debug_types sections. |
| std::vector<unsigned int> debug_info_sections; |
| std::vector<unsigned int> debug_types_sections; |
| |
| // Skip the first, dummy, section. |
| pshdrs = shdrs + This::shdr_size; |
| for (unsigned int i = 1; i < shnum; ++i, pshdrs += This::shdr_size) |
| { |
| typename This::Shdr shdr(pshdrs); |
| const unsigned int sh_name = shdr.get_sh_name(); |
| unsigned int sh_type = shdr.get_sh_type(); |
| |
| if (sh_name >= section_names_size) |
| { |
| this->error(_("bad section name offset for section %u: %lu"), |
| i, static_cast<unsigned long>(sh_name)); |
| return; |
| } |
| |
| const char* name = pnames + sh_name; |
| |
| if (!is_pass_two) |
| { |
| if (this->handle_gnu_warning_section(name, i, symtab)) |
| { |
| if (!relocatable && !parameters->options().shared()) |
| omit[i] = true; |
| } |
| |
| // The .note.GNU-stack section is special. It gives the |
| // protection flags that this object file requires for the stack |
| // in memory. |
| if (strcmp(name, ".note.GNU-stack") == 0) |
| { |
| seen_gnu_stack = true; |
| gnu_stack_flags |= shdr.get_sh_flags(); |
| omit[i] = true; |
| } |
| |
| // The .note.GNU-split-stack section is also special. It |
| // indicates that the object was compiled with |
| // -fsplit-stack. |
| if (this->handle_split_stack_section(name)) |
| { |
| if (!relocatable && !parameters->options().shared()) |
| omit[i] = true; |
| } |
| |
| // Skip attributes section. |
| if (parameters->target().is_attributes_section(name)) |
| { |
| omit[i] = true; |
| } |
| |
| // Handle .note.gnu.property sections. |
| if (sh_type == elfcpp::SHT_NOTE |
| && strcmp(name, ".note.gnu.property") == 0) |
| { |
| this->layout_gnu_property_section(layout, i); |
| omit[i] = true; |
| } |
| |
| bool discard = omit[i]; |
| if (!discard) |
| { |
| if (sh_type == elfcpp::SHT_GROUP) |
| { |
| if (!this->include_section_group(symtab, layout, i, name, |
| shdrs, pnames, |
| section_names_size, |
| &omit)) |
| discard = true; |
| } |
| else if ((shdr.get_sh_flags() & elfcpp::SHF_GROUP) == 0 |
| && Layout::is_linkonce(name)) |
| { |
| if (!this->include_linkonce_section(layout, i, name, shdr)) |
| discard = true; |
| } |
| } |
| |
| // Add the section to the incremental inputs layout. |
| Incremental_inputs* incremental_inputs = layout->incremental_inputs(); |
| if (incremental_inputs != NULL |
| && !discard |
| && can_incremental_update(sh_type)) |
| { |
| off_t sh_size = shdr.get_sh_size(); |
| section_size_type uncompressed_size; |
| if (this->section_is_compressed(i, &uncompressed_size)) |
| sh_size = uncompressed_size; |
| incremental_inputs->report_input_section(this, i, name, sh_size); |
| } |
| |
| if (discard) |
| { |
| // Do not include this section in the link. |
| out_sections[i] = NULL; |
| out_section_offsets[i] = invalid_address; |
| continue; |
| } |
| } |
| |
| if (is_pass_one && parameters->options().gc_sections()) |
| { |
| if (this->is_section_name_included(name) |
| || layout->keep_input_section (this, name) |
| || sh_type == elfcpp::SHT_INIT_ARRAY |
| || sh_type == elfcpp::SHT_FINI_ARRAY |
| || this->osabi().has_shf_retain(shdr.get_sh_flags())) |
| { |
| symtab->gc()->worklist().push_back(Section_id(this, i)); |
| } |
| // If the section name XXX can be represented as a C identifier |
| // it cannot be discarded if there are references to |
| // __start_XXX and __stop_XXX symbols. These need to be |
| // specially handled. |
| if (is_cident(name)) |
| { |
| symtab->gc()->add_cident_section(name, Section_id(this, i)); |
| } |
| } |
| |
| // When doing a relocatable link we are going to copy input |
| // reloc sections into the output. We only want to copy the |
| // ones associated with sections which are not being discarded. |
| // However, we don't know that yet for all sections. So save |
| // reloc sections and process them later. Garbage collection is |
| // not triggered when relocatable code is desired. |
| if (emit_relocs |
| && (sh_type == elfcpp::SHT_REL |
| || sh_type == elfcpp::SHT_RELA)) |
| { |
| reloc_sections.push_back(i); |
| continue; |
| } |
| |
| if (relocatable && sh_type == elfcpp::SHT_GROUP) |
| continue; |
| |
| // The .eh_frame section is special. It holds exception frame |
| // information that we need to read in order to generate the |
| // exception frame header. We process these after all the other |
| // sections so that the exception frame reader can reliably |
| // determine which sections are being discarded, and discard the |
| // corresponding information. |
| if (this->check_eh_frame_flags(&shdr) |
| && strcmp(name, ".eh_frame") == 0) |
| { |
| // If the target has a special unwind section type, let's |
| // canonicalize it here. |
| sh_type = unwind_section_type; |
| if (!relocatable) |
| { |
| if (is_pass_one) |
| { |
| if (this->is_deferred_layout()) |
| out_sections[i] = reinterpret_cast<Output_section*>(2); |
| else |
| out_sections[i] = reinterpret_cast<Output_section*>(1); |
| out_section_offsets[i] = invalid_address; |
| } |
| else if (this->is_deferred_layout()) |
| { |
| out_sections[i] = reinterpret_cast<Output_section*>(2); |
| out_section_offsets[i] = invalid_address; |
| this->deferred_layout_.push_back( |
| Deferred_layout(i, name, sh_type, pshdrs, |
| reloc_shndx[i], reloc_type[i])); |
| } |
| else |
| eh_frame_sections.push_back(i); |
| continue; |
| } |
| } |
| |
| if (is_pass_two && parameters->options().gc_sections()) |
| { |
| // This is executed during the second pass of garbage |
| // collection. do_layout has been called before and some |
| // sections have been already discarded. Simply ignore |
| // such sections this time around. |
| if (out_sections[i] == NULL) |
| { |
| gold_assert(out_section_offsets[i] == invalid_address); |
| continue; |
| } |
| if (((shdr.get_sh_flags() & elfcpp::SHF_ALLOC) != 0) |
| && symtab->gc()->is_section_garbage(this, i)) |
| { |
| if (parameters->options().print_gc_sections()) |
| gold_info(_("%s: removing unused section from '%s'" |
| " in file '%s'"), |
| program_name, this->section_name(i).c_str(), |
| this->name().c_str()); |
| out_sections[i] = NULL; |
| out_section_offsets[i] = invalid_address; |
| continue; |
| } |
| } |
| |
| if (is_pass_two && parameters->options().icf_enabled()) |
| { |
| if (out_sections[i] == NULL) |
| { |
| gold_assert(out_section_offsets[i] == invalid_address); |
| continue; |
| } |
| if (((shdr.get_sh_flags() & elfcpp::SHF_ALLOC) != 0) |
| && symtab->icf()->is_section_folded(this, i)) |
| { |
| if (parameters->options().print_icf_sections()) |
| { |
| Section_id folded = |
| symtab->icf()->get_folded_section(this, i); |
| Relobj* folded_obj = |
| reinterpret_cast<Relobj*>(folded.first); |
| gold_info(_("%s: ICF folding section '%s' in file '%s' " |
| "into '%s' in file '%s'"), |
| program_name, this->section_name(i).c_str(), |
| this->name().c_str(), |
| folded_obj->section_name(folded.second).c_str(), |
| folded_obj->name().c_str()); |
| } |
| out_sections[i] = NULL; |
| out_section_offsets[i] = invalid_address; |
| continue; |
| } |
| } |
| |
| // Defer layout here if input files are claimed by plugins. When gc |
| // is turned on this function is called twice; we only want to do this |
| // on the first pass. |
| if (!is_pass_two |
| && this->is_deferred_layout() |
| && (shdr.get_sh_flags() & elfcpp::SHF_ALLOC)) |
| { |
| this->deferred_layout_.push_back(Deferred_layout(i, name, sh_type, |
| pshdrs, |
| reloc_shndx[i], |
| reloc_type[i])); |
| // Put dummy values here; real values will be supplied by |
| // do_layout_deferred_sections. |
| out_sections[i] = reinterpret_cast<Output_section*>(2); |
| out_section_offsets[i] = invalid_address; |
| continue; |
| } |
| |
| // During gc_pass_two if a section that was previously deferred is |
| // found, do not layout the section as layout_deferred_sections will |
| // do it later from gold.cc. |
| if (is_pass_two |
| && (out_sections[i] == reinterpret_cast<Output_section*>(2))) |
| continue; |
| |
| if (is_pass_one) |
| { |
| // This is during garbage collection. The out_sections are |
| // assigned in the second call to this function. |
| out_sections[i] = reinterpret_cast<Output_section*>(1); |
| out_section_offsets[i] = invalid_address; |
| } |
| else |
| { |
| // When garbage collection is switched on the actual layout |
| // only happens in the second call. |
| this->layout_section(layout, i, name, shdr, sh_type, reloc_shndx[i], |
| reloc_type[i]); |
| |
| // When generating a .gdb_index section, we do additional |
| // processing of .debug_info and .debug_types sections after all |
| // the other sections for the same reason as above. |
| if (!relocatable |
| && parameters->options().gdb_index() |
| && !(shdr.get_sh_flags() & elfcpp::SHF_ALLOC)) |
| { |
| if (strcmp(name, ".debug_info") == 0 |
| || strcmp(name, ".zdebug_info") == 0) |
| debug_info_sections.push_back(i); |
| else if (strcmp(name, ".debug_types") == 0 |
| || strcmp(name, ".zdebug_types") == 0) |
| debug_types_sections.push_back(i); |
| } |
| } |
| |
| /* GCC uses .gnu.lto_.lto.<some_hash> as a LTO bytecode information |
| section. */ |
| const char *lto_section_name = ".gnu.lto_.lto."; |
| if (strncmp (name, lto_section_name, strlen (lto_section_name)) == 0) |
| { |
| section_size_type contents_len; |
| const unsigned char* pcontents |
| = this->section_contents(i, &contents_len, false); |
| if (contents_len >= sizeof(lto_section)) |
| { |
| const lto_section* lsection |
| = reinterpret_cast<const lto_section*>(pcontents); |
| if (lsection->slim_object) |
| layout->set_lto_slim_object(); |
| } |
| } |
| } |
| |
| if (!is_pass_two) |
| { |
| layout->merge_gnu_properties(this); |
| layout->layout_gnu_stack(seen_gnu_stack, gnu_stack_flags, this); |
| } |
| |
| // Handle the .eh_frame sections after the other sections. |
| gold_assert(!is_pass_one || eh_frame_sections.empty()); |
| for (std::vector<unsigned int>::const_iterator p = eh_frame_sections.begin(); |
| p != eh_frame_sections.end(); |
| ++p) |
| { |
| unsigned int i = *p; |
| const unsigned char* pshdr; |
| pshdr = section_headers_data + i * This::shdr_size; |
| typename This::Shdr shdr(pshdr); |
| |
| this->layout_eh_frame_section(layout, |
| symbols_data, |
| symbols_size, |
| symbol_names_data, |
| symbol_names_size, |
| i, |
| shdr, |
| reloc_shndx[i], |
| reloc_type[i]); |
| } |
| |
| // When doing a relocatable link handle the reloc sections at the |
| // end. Garbage collection and Identical Code Folding is not |
| // turned on for relocatable code. |
| if (emit_relocs) |
| this->size_relocatable_relocs(); |
| |
| gold_assert(!is_two_pass || reloc_sections.empty()); |
| |
| for (std::vector<unsigned int>::const_iterator p = reloc_sections.begin(); |
| p != reloc_sections.end(); |
| ++p) |
| { |
| unsigned int i = *p; |
| const unsigned char* pshdr; |
| pshdr = section_headers_data + i * This::shdr_size; |
| typename This::Shdr shdr(pshdr); |
| |
| unsigned int data_shndx = this->adjust_shndx(shdr.get_sh_info()); |
| if (data_shndx >= shnum) |
| { |
| // We already warned about this above. |
| continue; |
| } |
| |
| Output_section* data_section = out_sections[data_shndx]; |
| if (data_section == reinterpret_cast<Output_section*>(2)) |
| { |
| if (is_pass_two) |
| continue; |
| // The layout for the data section was deferred, so we need |
| // to defer the relocation section, too. |
| const char* name = pnames + shdr.get_sh_name(); |
| this->deferred_layout_relocs_.push_back( |
| Deferred_layout(i, name, shdr.get_sh_type(), pshdr, 0, |
| elfcpp::SHT_NULL)); |
| out_sections[i] = reinterpret_cast<Output_section*>(2); |
| out_section_offsets[i] = invalid_address; |
| continue; |
| } |
| if (data_section == NULL) |
| { |
| out_sections[i] = NULL; |
| out_section_offsets[i] = invalid_address; |
| continue; |
| } |
| |
| Relocatable_relocs* rr = new Relocatable_relocs(); |
| this->set_relocatable_relocs(i, rr); |
| |
| Output_section* os = layout->layout_reloc(this, i, shdr, data_section, |
| rr); |
| out_sections[i] = os; |
| out_section_offsets[i] = invalid_address; |
| } |
| |
| // When building a .gdb_index section, scan the .debug_info and |
| // .debug_types sections. |
| gold_assert(!is_pass_one |
| || (debug_info_sections.empty() && debug_types_sections.empty())); |
| for (std::vector<unsigned int>::const_iterator p |
| = debug_info_sections.begin(); |
| p != debug_info_sections.end(); |
| ++p) |
| { |
| unsigned int i = *p; |
| layout->add_to_gdb_index(false, this, symbols_data, symbols_size, |
| i, reloc_shndx[i], reloc_type[i]); |
| } |
| for (std::vector<unsigned int>::const_iterator p |
| = debug_types_sections.begin(); |
| p != debug_types_sections.end(); |
| ++p) |
| { |
| unsigned int i = *p; |
| layout->add_to_gdb_index(true, this, symbols_data, symbols_size, |
| i, reloc_shndx[i], reloc_type[i]); |
| } |
| |
| if (is_pass_two) |
| { |
| delete[] gc_sd->section_headers_data; |
| delete[] gc_sd->section_names_data; |
| delete[] gc_sd->symbols_data; |
| delete[] gc_sd->symbol_names_data; |
| this->set_symbols_data(NULL); |
| } |
| else |
| { |
| delete sd->section_headers; |
| sd->section_headers = NULL; |
| delete sd->section_names; |
| sd->section_names = NULL; |
| } |
| } |
| |
| // Layout sections whose layout was deferred while waiting for |
| // input files from a plugin. |
| |
| template<int size, bool big_endian> |
| void |
| Sized_relobj_file<size, big_endian>::do_layout_deferred_sections(Layout* layout) |
| { |
| typename std::vector<Deferred_layout>::iterator deferred; |
| |
| for (deferred = this->deferred_layout_.begin(); |
| deferred != this->deferred_layout_.end(); |
| ++deferred) |
| { |
| typename This::Shdr shdr(deferred->shdr_data_); |
| |
| if (!parameters->options().relocatable() |
| && deferred->name_ == ".eh_frame" |
| && this->check_eh_frame_flags(&shdr)) |
| { |
| // Checking is_section_included is not reliable for |
| // .eh_frame sections, because they do not have an output |
| // section. This is not a problem normally because we call |
| // layout_eh_frame_section unconditionally, but when |
| // deferring sections that is not true. We don't want to |
| // keep all .eh_frame sections because that will cause us to |
| // keep all sections that they refer to, which is the wrong |
| // way around. Instead, the eh_frame code will discard |
| // .eh_frame sections that refer to discarded sections. |
| |
| // Reading the symbols again here may be slow. |
| Read_symbols_data sd; |
| this->base_read_symbols(&sd); |
| this->layout_eh_frame_section(layout, |
| sd.symbols->data(), |
| sd.symbols_size, |
| sd.symbol_names->data(), |
| sd.symbol_names_size, |
| deferred->shndx_, |
| shdr, |
| deferred->reloc_shndx_, |
| deferred->reloc_type_); |
| continue; |
| } |
| |
| // If the section is not included, it is because the garbage collector |
| // decided it is not needed. Avoid reverting that decision. |
| if (!this->is_section_included(deferred->shndx_)) |
| continue; |
| |
| this->layout_section(layout, deferred->shndx_, deferred->name_.c_str(), |
| shdr, shdr.get_sh_type(), deferred->reloc_shndx_, |
| deferred->reloc_type_); |
| } |
| |
| this->deferred_layout_.clear(); |
| |
| // Now handle the deferred relocation sections. |
| |
| Output_sections& out_sections(this->output_sections()); |
| std::vector<Address>& out_section_offsets(this->section_offsets()); |
| |
| for (deferred = this->deferred_layout_relocs_.begin(); |
| deferred != this->deferred_layout_relocs_.end(); |
| ++deferred) |
| { |
| unsigned int shndx = deferred->shndx_; |
| typename This::Shdr shdr(deferred->shdr_data_); |
| unsigned int data_shndx = this->adjust_shndx(shdr.get_sh_info()); |
| |
| Output_section* data_section = out_sections[data_shndx]; |
| if (data_section == NULL) |
| { |
| out_sections[shndx] = NULL; |
| out_section_offsets[shndx] = invalid_address; |
| continue; |
| } |
| |
| Relocatable_relocs* rr = new Relocatable_relocs(); |
| this->set_relocatable_relocs(shndx, rr); |
| |
| Output_section* os = layout->layout_reloc(this, shndx, shdr, |
| data_section, rr); |
| out_sections[shndx] = os; |
| out_section_offsets[shndx] = invalid_address; |
| } |
| } |
| |
| // Add the symbols to the symbol table. |
| |
| template<int size, bool big_endian> |
| void |
| Sized_relobj_file<size, big_endian>::do_add_symbols(Symbol_table* symtab, |
| Read_symbols_data* sd, |
| Layout* layout) |
| { |
| if (sd->symbols == NULL) |
| { |
| gold_assert(sd->symbol_names == NULL); |
| return; |
| } |
| |
| const int sym_size = This::sym_size; |
| size_t symcount = ((sd->symbols_size - sd->external_symbols_offset) |
| / sym_size); |
| if (symcount * sym_size != sd->symbols_size - sd->external_symbols_offset) |
| { |
| this->error(_("size of symbols is not multiple of symbol size")); |
| return; |
| } |
| |
| this->symbols_.resize(symcount); |
| |
| if (!parameters->options().relocatable() |
| && layout->is_lto_slim_object ()) |
| gold_info(_("%s: plugin needed to handle lto object"), |
| this->name().c_str()); |
| |
| const char* sym_names = |
| reinterpret_cast<const char*>(sd->symbol_names->data()); |
| symtab->add_from_relobj(this, |
| sd->symbols->data() + sd->external_symbols_offset, |
| symcount, this->local_symbol_count_, |
| sym_names, sd->symbol_names_size, |
| &this->symbols_, |
| &this->defined_count_); |
| |
| delete sd->symbols; |
| sd->symbols = NULL; |
| delete sd->symbol_names; |
| sd->symbol_names = NULL; |
| } |
| |
| // Find out if this object, that is a member of a lib group, should be included |
| // in the link. We check every symbol defined by this object. If the symbol |
| // table has a strong undefined reference to that symbol, we have to include |
| // the object. |
| |
| template<int size, bool big_endian> |
| Archive::Should_include |
| Sized_relobj_file<size, big_endian>::do_should_include_member( |
| Symbol_table* symtab, |
| Layout* layout, |
| Read_symbols_data* sd, |
| std::string* why) |
| { |
| char* tmpbuf = NULL; |
| size_t tmpbuflen = 0; |
| const char* sym_names = |
| reinterpret_cast<const char*>(sd->symbol_names->data()); |
| const unsigned char* syms = |
| sd->symbols->data() + sd->external_symbols_offset; |
| const int sym_size = elfcpp::Elf_sizes<size>::sym_size; |
| size_t symcount = ((sd->symbols_size - sd->external_symbols_offset) |
| / sym_size); |
| |
| const unsigned char* p = syms; |
| |
| for (size_t i = 0; i < symcount; ++i, p += sym_size) |
| { |
| elfcpp::Sym<size, big_endian> sym(p); |
| unsigned int st_shndx = sym.get_st_shndx(); |
| if (st_shndx == elfcpp::SHN_UNDEF) |
| continue; |
| |
| unsigned int st_name = sym.get_st_name(); |
| const char* name = sym_names + st_name; |
| Symbol* symbol; |
| Archive::Should_include t = Archive::should_include_member(symtab, |
| layout, |
| name, |
| &symbol, why, |
| &tmpbuf, |
| &tmpbuflen); |
| if (t == Archive::SHOULD_INCLUDE_YES) |
| { |
| if (tmpbuf != NULL) |
| free(tmpbuf); |
| return t; |
| } |
| } |
| if (tmpbuf != NULL) |
| free(tmpbuf); |
| return Archive::SHOULD_INCLUDE_UNKNOWN; |
| } |
| |
| // Iterate over global defined symbols, calling a visitor class V for each. |
| |
| template<int size, bool big_endian> |
| void |
| Sized_relobj_file<size, big_endian>::do_for_all_global_symbols( |
| Read_symbols_data* sd, |
| Library_base::Symbol_visitor_base* v) |
| { |
| const char* sym_names = |
| reinterpret_cast<const char*>(sd->symbol_names->data()); |
| const unsigned char* syms = |
| sd->symbols->data() + sd->external_symbols_offset; |
| const int sym_size = elfcpp::Elf_sizes<size>::sym_size; |
| size_t symcount = ((sd->symbols_size - sd->external_symbols_offset) |
| / sym_size); |
| const unsigned char* p = syms; |
| |
| for (size_t i = 0; i < symcount; ++i, p += sym_size) |
| { |
| elfcpp::Sym<size, big_endian> sym(p); |
| if (sym.get_st_shndx() != elfcpp::SHN_UNDEF) |
| v->visit(sym_names + sym.get_st_name()); |
| } |
| } |
| |
| // Return whether the local symbol SYMNDX has a PLT offset. |
| |
| template<int size, bool big_endian> |
| bool |
| Sized_relobj_file<size, big_endian>::local_has_plt_offset( |
| unsigned int symndx) const |
| { |
| typename Local_plt_offsets::const_iterator p = |
| this->local_plt_offsets_.find(symndx); |
| return p != this->local_plt_offsets_.end(); |
| } |
| |
| // Get the PLT offset of a local symbol. |
| |
| template<int size, bool big_endian> |
| unsigned int |
| Sized_relobj_file<size, big_endian>::do_local_plt_offset( |
| unsigned int symndx) const |
| { |
| typename Local_plt_offsets::const_iterator p = |
| this->local_plt_offsets_.find(symndx); |
| gold_assert(p != this->local_plt_offsets_.end()); |
| return p->second; |
| } |
| |
| // Set the PLT offset of a local symbol. |
| |
| template<int size, bool big_endian> |
| void |
| Sized_relobj_file<size, big_endian>::set_local_plt_offset( |
| unsigned int symndx, unsigned int plt_offset) |
| { |
| std::pair<typename Local_plt_offsets::iterator, bool> ins = |
| this->local_plt_offsets_.insert(std::make_pair(symndx, plt_offset)); |
| gold_assert(ins.second); |
| } |
| |
| // First pass over the local symbols. Here we add their names to |
| // *POOL and *DYNPOOL, and we store the symbol value in |
| // THIS->LOCAL_VALUES_. This function is always called from a |
| // singleton thread. This is followed by a call to |
| // finalize_local_symbols. |
| |
| template<int size, bool big_endian> |
| void |
| Sized_relobj_file<size, big_endian>::do_count_local_symbols(Stringpool* pool, |
| Stringpool* dynpool) |
| { |
| gold_assert(this->symtab_shndx_ != -1U); |
| if (this->symtab_shndx_ == 0) |
| { |
| // This object has no symbols. Weird but legal. |
| return; |
| } |
| |
| // Read the symbol table section header. |
| const unsigned int symtab_shndx = this->symtab_shndx_; |
| typename This::Shdr symtabshdr(this, |
| this->elf_file_.section_header(symtab_shndx)); |
| gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB); |
| |
| // Read the local symbols. |
| 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; |
| const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(), |
| locsize, true, true); |
| |
| // Read the symbol names. |
| const unsigned int strtab_shndx = |
| this->adjust_shndx(symtabshdr.get_sh_link()); |
| section_size_type strtab_size; |
| const unsigned char* pnamesu = this->section_contents(strtab_shndx, |
| &strtab_size, |
| true); |
| const char* pnames = reinterpret_cast<const char*>(pnamesu); |
| |
| // Loop over the local symbols. |
| |
| const Output_sections& out_sections(this->output_sections()); |
| std::vector<Address>& out_section_offsets(this->section_offsets()); |
| unsigned int shnum = this->shnum(); |
| unsigned int count = 0; |
| unsigned int dyncount = 0; |
| // Skip the first, dummy, symbol. |
| psyms += sym_size; |
| bool strip_all = parameters->options().strip_all(); |
| bool discard_all = parameters->options().discard_all(); |
| bool discard_locals = parameters->options().discard_locals(); |
| bool discard_sec_merge = parameters->options().discard_sec_merge(); |
| for (unsigned int i = 1; i < loccount; ++i, psyms += sym_size) |
| { |
| elfcpp::Sym<size, big_endian> sym(psyms); |
| |
| Symbol_value<size>& lv(this->local_values_[i]); |
| |
| bool is_ordinary; |
| unsigned int shndx = this->adjust_sym_shndx(i, sym.get_st_shndx(), |
| &is_ordinary); |
| lv.set_input_shndx(shndx, is_ordinary); |
| |
| if (sym.get_st_type() == elfcpp::STT_SECTION) |
| lv.set_is_section_symbol(); |
| else if (sym.get_st_type() == elfcpp::STT_TLS) |
| lv.set_is_tls_symbol(); |
| else if (sym.get_st_type() == elfcpp::STT_GNU_IFUNC) |
| lv.set_is_ifunc_symbol(); |
| |
| // Save the input symbol value for use in do_finalize_local_symbols(). |
| lv.set_input_value(sym.get_st_value()); |
| |
| // Decide whether this symbol should go into the output file. |
| |
| if (is_ordinary |
| && shndx < shnum |
| && (out_sections[shndx] == NULL |
| || (out_sections[shndx]->order() == ORDER_EHFRAME |
| && out_section_offsets[shndx] == invalid_address))) |
| { |
| // This is either a discarded section or an optimized .eh_frame |
| // section. |
| lv.set_no_output_symtab_entry(); |
| gold_assert(!lv.needs_output_dynsym_entry()); |
| continue; |
| } |
| |
| if (sym.get_st_type() == elfcpp::STT_SECTION |
| || !this->adjust_local_symbol(&lv)) |
| { |
| lv.set_no_output_symtab_entry(); |
| gold_assert(!lv.needs_output_dynsym_entry()); |
| continue; |
| } |
| |
| if (sym.get_st_name() >= strtab_size) |
| { |
| this->error(_("local symbol %u section name out of range: %u >= %u"), |
| i, sym.get_st_name(), |
| static_cast<unsigned int>(strtab_size)); |
| lv.set_no_output_symtab_entry(); |
| continue; |
| } |
| |
| const char* name = pnames + sym.get_st_name(); |
| |
| // If needed, add the symbol to the dynamic symbol table string pool. |
| if (lv.needs_output_dynsym_entry()) |
| { |
| dynpool->add(name, true, NULL); |
| ++dyncount; |
| } |
| |
| if (strip_all |
| || (discard_all && lv.may_be_discarded_from_output_symtab())) |
| { |
| lv.set_no_output_symtab_entry(); |
| continue; |
| } |
| |
| // By default, discard temporary local symbols in merge sections. |
| // If --discard-locals option is used, discard all temporary local |
| // symbols. These symbols start with system-specific local label |
| // prefixes, typically .L for ELF system. We want to be compatible |
| // with GNU ld so here we essentially use the same check in |
| // bfd_is_local_label(). The code is different because we already |
| // know that: |
| // |
| // - the symbol is local and thus cannot have global or weak binding. |
| // - the symbol is not a section symbol. |
| // - the symbol has a name. |
| // |
| // We do not discard a symbol if it needs a dynamic symbol entry. |
| if ((discard_locals |
| || (discard_sec_merge |
| && is_ordinary |
| && out_section_offsets[shndx] == invalid_address)) |
| && sym.get_st_type() != elfcpp::STT_FILE |
| && !lv.needs_output_dynsym_entry() |
| && lv.may_be_discarded_from_output_symtab() |
| && parameters->target().is_local_label_name(name)) |
| { |
| lv.set_no_output_symtab_entry(); |
| continue; |
| } |
| |
| // Discard the local symbol if -retain_symbols_file is specified |
| // and the local symbol is not in that file. |
| if (!parameters->options().should_retain_symbol(name)) |
| { |
| lv.set_no_output_symtab_entry(); |
| continue; |
| } |
| |
| // Add the symbol to the symbol table string pool. |
| pool->add(name, true, NULL); |
| ++count; |
| } |
| |
| this->output_local_symbol_count_ = count; |
| this->output_local_dynsym_count_ = dyncount; |
| } |
| |
| // Compute the final value of a local symbol. |
| |
| template<int size, bool big_endian> |
| typename Sized_relobj_file<size, big_endian>::Compute_final_local_value_status |
| Sized_relobj_file<size, big_endian>::compute_final_local_value_internal( |
| unsigned int r_sym, |
| const Symbol_value<size>* lv_in, |
| Symbol_value<size>* lv_out, |
| bool relocatable, |
| const Output_sections& out_sections, |
| const std::vector<Address>& out_offsets, |
| const Symbol_table* symtab) |
| { |
| // We are going to overwrite *LV_OUT, if it has a merged symbol value, |
| // we may have a memory leak. |
| gold_assert(lv_out->has_output_value()); |
| |
| bool is_ordinary; |
| unsigned int shndx = lv_in->input_shndx(&is_ordinary); |
| |
| // Set the output symbol value. |
| |
| if (!is_ordinary) |
| { |
| if (shndx == elfcpp::SHN_ABS || Symbol::is_common_shndx(shndx)) |
| lv_out->set_output_value(lv_in->input_value()); |
| else |
| { |
| this->error(_("unknown section index %u for local symbol %u"), |
| shndx, r_sym); |
| lv_out->set_output_value(0); |
| return This::CFLV_ERROR; |
| } |
| } |
| else |
| { |
| if (shndx >= this->shnum()) |
| { |
| this->error(_("local symbol %u section index %u out of range"), |
| r_sym, shndx); |
| lv_out->set_output_value(0); |
| return This::CFLV_ERROR; |
| } |
| |
| Output_section* os = out_sections[shndx]; |
| Address secoffset = out_offsets[shndx]; |
| if (symtab->is_section_folded(this, shndx)) |
| { |
| gold_assert(os == NULL && secoffset == invalid_address); |
| // Get the os of the section it is folded onto. |
| Section_id folded = symtab->icf()->get_folded_section(this, |
| shndx); |
| gold_assert(folded.first != NULL); |
| Sized_relobj_file<size, big_endian>* folded_obj = reinterpret_cast |
| <Sized_relobj_file<size, big_endian>*>(folded.first); |
| os = folded_obj->output_section(folded.second); |
| gold_assert(os != NULL); |
| secoffset = folded_obj->get_output_section_offset(folded.second); |
| |
| // This could be a relaxed input section. |
| if (secoffset == invalid_address) |
| { |
| const Output_relaxed_input_section* relaxed_section = |
| os->find_relaxed_input_section(folded_obj, folded.second); |
| gold_assert(relaxed_section != NULL); |
| secoffset = relaxed_section->address() - os->address(); |
| } |
| } |
| |
| if (os == NULL) |
| { |
| // This local symbol belongs to a section we are discarding. |
| // In some cases when applying relocations later, we will |
| // attempt to match it to the corresponding kept section, |
| // so we leave the input value unchanged here. |
| return This::CFLV_DISCARDED; |
| } |
| else if (secoffset == invalid_address) |
| { |
| uint64_t start; |
| |
| // This is a SHF_MERGE section or one which otherwise |
| // requires special handling. |
| if (os->order() == ORDER_EHFRAME) |
| { |
| // This local symbol belongs to a discarded or optimized |
| // .eh_frame section. Just treat it like the case in which |
| // os == NULL above. |
| gold_assert(this->has_eh_frame_); |
| return This::CFLV_DISCARDED; |
| } |
| else if (!lv_in->is_section_symbol()) |
| { |
| // This is not a section symbol. We can determine |
| // the final value now. |
| uint64_t value = |
| os->output_address(this, shndx, lv_in->input_value()); |
| if (relocatable) |
| value -= os->address(); |
| lv_out->set_output_value(value); |
| } |
| else if (!os->find_starting_output_address(this, shndx, &start)) |
| { |
| // This is a section symbol, but apparently not one in a |
| // merged section. First check to see if this is a relaxed |
| // input section. If so, use its address. Otherwise just |
| // use the start of the output section. This happens with |
| // relocatable links when the input object has section |
| // symbols for arbitrary non-merge sections. |
| const Output_section_data* posd = |
| os->find_relaxed_input_section(this, shndx); |
| if (posd != NULL) |
| { |
| uint64_t value = posd->address(); |
| if (relocatable) |
| value -= os->address(); |
| lv_out->set_output_value(value); |
| } |
| else |
| lv_out->set_output_value(os->address()); |
| } |
| else |
| { |
| // We have to consider the addend to determine the |
| // value to use in a relocation. START is the start |
| // of this input section. If we are doing a relocatable |
| // link, use offset from start output section instead of |
| // address. |
| Address adjusted_start = |
| relocatable ? start - os->address() : start; |
| Merged_symbol_value<size>* msv = |
| new Merged_symbol_value<size>(lv_in->input_value(), |
| adjusted_start); |
| lv_out->set_merged_symbol_value(msv); |
| } |
| } |
| else if (lv_in->is_tls_symbol() |
| || (lv_in->is_section_symbol() |
| && (os->flags() & elfcpp::SHF_TLS))) |
| lv_out->set_output_value(os->tls_offset() |
| + secoffset |
| + lv_in->input_value()); |
| else |
| lv_out->set_output_value((relocatable ? 0 : os->address()) |
| + secoffset |
| + lv_in->input_value()); |
| } |
| return This::CFLV_OK; |
| } |
| |
| // Compute final local symbol value. R_SYM is the index of a local |
| // symbol in symbol table. LV points to a symbol value, which is |
| // expected to hold the input value and to be over-written by the |
| // final value. SYMTAB points to a symbol table. Some targets may want |
| // to know would-be-finalized local symbol values in relaxation. |
| // Hence we provide this method. Since this method updates *LV, a |
| // callee should make a copy of the original local symbol value and |
| // use the copy instead of modifying an object's local symbols before |
| // everything is finalized. The caller should also free up any allocated |
| // memory in the return value in *LV. |
| template<int size, bool big_endian> |
| typename Sized_relobj_file<size, big_endian>::Compute_final_local_value_status |
| Sized_relobj_file<size, big_endian>::compute_final_local_value( |
| unsigned int r_sym, |
| const Symbol_value<size>* lv_in, |
| Symbol_value<size>* lv_out, |
| const Symbol_table* symtab) |
| { |
| // This is just a wrapper of compute_final_local_value_internal. |
| const bool relocatable = parameters->options().relocatable(); |
| const Output_sections& out_sections(this->output_sections()); |
| const std::vector<Address>& out_offsets(this->section_offsets()); |
| return this->compute_final_local_value_internal(r_sym, lv_in, lv_out, |
| relocatable, out_sections, |
| out_offsets, symtab); |
| } |
| |
| // Finalize the local symbols. Here we set the final value in |
| // THIS->LOCAL_VALUES_ and set their output symbol table indexes. |
| // This function is always called from a singleton thread. The actual |
| // output of the local symbols will occur in a separate task. |
| |
| template<int size, bool big_endian> |
| unsigned int |
| Sized_relobj_file<size, big_endian>::do_finalize_local_symbols( |
| unsigned int index, |
| off_t off, |
| Symbol_table* symtab) |
| { |
| gold_assert(off == static_cast<off_t>(align_address(off, size >> 3))); |
| |
| const unsigned int loccount = this->local_symbol_count_; |
| this->local_symbol_offset_ = off; |
| |
| const bool relocatable = parameters->options().relocatable(); |
| const Output_sections& out_sections(this->output_sections()); |
| const std::vector<Address>& out_offsets(this->section_offsets()); |
| |
| for (unsigned int i = 1; i < loccount; ++i) |
| { |
| Symbol_value<size>* lv = &this->local_values_[i]; |
| |
| Compute_final_local_value_status cflv_status = |
| this->compute_final_local_value_internal(i, lv, lv, relocatable, |
| out_sections, out_offsets, |
| symtab); |
| switch (cflv_status) |
| { |
| case CFLV_OK: |
| if (!lv->is_output_symtab_index_set()) |
| { |
| lv->set_output_symtab_index(index); |
| ++index; |
| } |
| if (lv->is_ifunc_symbol() |
| && (lv->has_output_symtab_entry() |
| || lv->needs_output_dynsym_entry())) |
| symtab->set_has_gnu_output(); |
| break; |
| case CFLV_DISCARDED: |
| case CFLV_ERROR: |
| // Do nothing. |
| break; |
| default: |
| gold_unreachable(); |
| } |
| } |
| return index; |
| } |
| |
| // Set the output dynamic symbol table indexes for the local variables. |
| |
| template<int size, bool big_endian> |
| unsigned int |
| Sized_relobj_file<size, big_endian>::do_set_local_dynsym_indexes( |
| unsigned int index) |
| { |
| const unsigned int loccount = this->local_symbol_count_; |
| for (unsigned int i = 1; i < loccount; ++i) |
| { |
| Symbol_value<size>& lv(this->local_values_[i]); |
| if (lv.needs_output_dynsym_entry()) |
| { |
| lv.set_output_dynsym_index(index); |
| ++index; |
| } |
| } |
| return index; |
| } |
| |
| // Set the offset where local dynamic symbol information will be stored. |
| // Returns the count of local symbols contributed to the symbol table by |
| // this object. |
| |
| template<int size, bool big_endian> |
| unsigned int |
| Sized_relobj_file<size, big_endian>::do_set_local_dynsym_offset(off_t off) |
| { |
| gold_assert(off == static_cast<off_t>(align_address(off, size >> 3))); |
| this->local_dynsym_offset_ = off; |
| return this->output_local_dynsym_count_; |
| } |
| |
| // If Symbols_data is not NULL get the section flags from here otherwise |
| // get it from the file. |
| |
| template<int size, bool big_endian> |
| uint64_t |
| Sized_relobj_file<size, big_endian>::do_section_flags(unsigned int shndx) |
| { |
| Symbols_data* sd = this->get_symbols_data(); |
| if (sd != NULL) |
| { |
| const unsigned char* pshdrs = sd->section_headers_data |
| + This::shdr_size * shndx; |
| typename This::Shdr shdr(pshdrs); |
| return shdr.get_sh_flags(); |
| } |
| // If sd is NULL, read the section header from the file. |
| return this->elf_file_.section_flags(shndx); |
| } |
| |
| // Get the section's ent size from Symbols_data. Called by get_section_contents |
| // in icf.cc |
| |
| template<int size, bool big_endian> |
| uint64_t |
| Sized_relobj_file<size, big_endian>::do_section_entsize(unsigned int shndx) |
| { |
| Symbols_data* sd = this->get_symbols_data(); |
| gold_assert(sd != NULL); |
| |
| const unsigned char* pshdrs = sd->section_headers_data |
| + This::shdr_size * shndx; |
| typename This::Shdr shdr(pshdrs); |
| return shdr.get_sh_entsize(); |
| } |
| |
| // Write out the local symbols. |
| |
| template<int size, bool big_endian> |
| void |
| Sized_relobj_file<size, big_endian>::write_local_symbols( |
| Output_file* of, |
| const Stringpool* sympool, |
| const Stringpool* dynpool, |
| Output_symtab_xindex* symtab_xindex, |
| Output_symtab_xindex* dynsym_xindex, |
| off_t symtab_off) |
| { |
| const bool strip_all = parameters->options().strip_all(); |
| if (strip_all) |
| { |
| if (this->output_local_dynsym_count_ == 0) |
| return; |
| this->output_local_symbol_count_ = 0; |
| } |
| |
| gold_assert(this->symtab_shndx_ != -1U); |
| if (this->symtab_shndx_ == 0) |
| { |
| // This object has no symbols. Weird but legal. |
| return; |
| } |
| |
| // Read the symbol table section header. |
| const unsigned int symtab_shndx = this->symtab_shndx_; |
| typename This::Shdr symtabshdr(this, |
| this->elf_file_.section_header(symtab_shndx)); |
| gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB); |
| const unsigned int loccount = this->local_symbol_count_; |
| gold_assert(loccount == symtabshdr.get_sh_info()); |
| |
| // Read the local symbols. |
| const int sym_size = This::sym_size; |
| off_t locsize = loccount * sym_size; |
| const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(), |
| locsize, true, false); |
| |
| // Read the symbol names. |
| const unsigned int strtab_shndx = |
| this->adjust_shndx(symtabshdr.get_sh_link()); |
| section_size_type strtab_size; |
| const unsigned char* pnamesu = this->section_contents(strtab_shndx, |
| &strtab_size, |
| false); |
| const char* pnames = reinterpret_cast<const char*>(pnamesu); |
| |
| // Get views into the output file for the portions of the symbol table |
| // and the dynamic symbol table that we will be writing. |
| off_t output_size = this->output_local_symbol_count_ * sym_size; |
| unsigned char* oview = NULL; |
| if (output_size > 0) |
| oview = of->get_output_view(symtab_off + this->local_symbol_offset_, |
| output_size); |
| |
| off_t dyn_output_size = this->output_local_dynsym_count_ * sym_size; |
| unsigned char* dyn_oview = NULL; |
| if (dyn_output_size > 0) |
| dyn_oview = of->get_output_view(this->local_dynsym_offset_, |
| dyn_output_size); |
| |
| const Output_sections& out_sections(this->output_sections()); |
| |
| gold_assert(this->local_values_.size() == loccount); |
| |
| unsigned char* ov = oview; |
| unsigned char* dyn_ov = dyn_oview; |
| psyms += sym_size; |
| for (unsigned int i = 1; i < loccount; ++i, psyms += sym_size) |
| { |
| elfcpp::Sym<size, big_endian> isym(psyms); |
| |
| Symbol_value<size>& lv(this->local_values_[i]); |
| |
| bool is_ordinary; |
| unsigned int st_shndx = this->adjust_sym_shndx(i, isym.get_st_shndx(), |
| &is_ordinary); |
| if (is_ordinary) |
| { |
| gold_assert(st_shndx < out_sections.size()); |
| if (out_sections[st_shndx] == NULL) |
| continue; |
| st_shndx = out_sections[st_shndx]->out_shndx(); |
| if (st_shndx >= elfcpp::SHN_LORESERVE) |
| { |
| if (lv.has_output_symtab_entry()) |
| symtab_xindex->add(lv.output_symtab_index(), st_shndx); |
| if (lv.has_output_dynsym_entry()) |
| dynsym_xindex->add(lv.output_dynsym_index(), st_shndx); |
| st_shndx = elfcpp::SHN_XINDEX; |
| } |
| } |
| |
| // Write the symbol to the output symbol table. |
| if (lv.has_output_symtab_entry()) |
| { |
| elfcpp::Sym_write<size, big_endian> osym(ov); |
| |
| gold_assert(isym.get_st_name() < strtab_size); |
| const char* name = pnames + isym.get_st_name(); |
| osym.put_st_name(sympool->get_offset(name)); |
| osym.put_st_value(lv.value(this, 0)); |
| osym.put_st_size(isym.get_st_size()); |
| osym.put_st_info(isym.get_st_info()); |
| osym.put_st_other(isym.get_st_other()); |
| osym.put_st_shndx(st_shndx); |
| |
| ov += sym_size; |
| } |
| |
| // Write the symbol to the output dynamic symbol table. |
| if (lv.has_output_dynsym_entry()) |
| { |
| gold_assert(dyn_ov < dyn_oview + dyn_output_size); |
| elfcpp::Sym_write<size, big_endian> osym(dyn_ov); |
| |
| gold_assert(isym.get_st_name() < strtab_size); |
| const char* name = pnames + isym.get_st_name(); |
| osym.put_st_name(dynpool->get_offset(name)); |
| osym.put_st_value(lv.value(this, 0)); |
| osym.put_st_size(isym.get_st_size()); |
| osym.put_st_info(isym.get_st_info()); |
| osym.put_st_other(isym.get_st_other()); |
| osym.put_st_shndx(st_shndx); |
| |
| dyn_ov += sym_size; |
| } |
| } |
| |
| |
| if (output_size > 0) |
| { |
| gold_assert(ov - oview == output_size); |
| of->write_output_view(symtab_off + this->local_symbol_offset_, |
| output_size, oview); |
| } |
| |
| if (dyn_output_size > 0) |
| { |
| gold_assert(dyn_ov - dyn_oview == dyn_output_size); |
| of->write_output_view(this->local_dynsym_offset_, dyn_output_size, |
| dyn_oview); |
| } |
| } |
| |
| // Set *INFO to symbolic information about the offset OFFSET in the |
| // section SHNDX. Return true if we found something, false if we |
| // found nothing. |
| |
| template<int size, bool big_endian> |
| bool |
| Sized_relobj_file<size, big_endian>::get_symbol_location_info( |
| unsigned int shndx, |
| off_t offset, |
| Symbol_location_info* info) |
| { |
| if (this->symtab_shndx_ == 0) |
| return false; |
| |
| section_size_type symbols_size; |
| const unsigned char* symbols = this->section_contents(this->symtab_shndx_, |
| &symbols_size, |
| false); |
| |
| unsigned int symbol_names_shndx = |
| this->adjust_shndx(this->section_link(this->symtab_shndx_)); |
| section_size_type names_size; |
| const unsigned char* symbol_names_u = |
| this->section_contents(symbol_names_shndx, &names_size, false); |
| const char* symbol_names = reinterpret_cast<const char*>(symbol_names_u); |
| |
| const int sym_size = This::sym_size; |
| const size_t count = symbols_size / sym_size; |
| |
| const unsigned char* p = symbols; |
| for (size_t i = 0; i < count; ++i, p += sym_size) |
| { |
| elfcpp::Sym<size, big_endian> sym(p); |
| |
| if (sym.get_st_type() == elfcpp::STT_FILE) |
| { |
| if (sym.get_st_name() >= names_size) |
| info->source_file = "(invalid)"; |
| else |
| info->source_file = symbol_names + sym.get_st_name(); |
| continue; |
| } |
| |
| bool is_ordinary; |
| unsigned int st_shndx = this->adjust_sym_shndx(i, sym.get_st_shndx(), |
| &is_ordinary); |
| if (is_ordinary |
| && st_shndx == shndx |
| && static_cast<off_t>(sym.get_st_value()) <= offset |
| && (static_cast<off_t>(sym.get_st_value() + sym.get_st_size()) |
| > offset)) |
| { |
| info->enclosing_symbol_type = sym.get_st_type(); |
| if (sym.get_st_name() > names_size) |
| info->enclosing_symbol_name = "(invalid)"; |
| else |
| { |
| info->enclosing_symbol_name = symbol_names + sym.get_st_name(); |
| if (parameters->options().do_demangle()) |
| { |
| char* demangled_name = cplus_demangle( |
| info->enclosing_symbol_name.c_str(), |
| DMGL_ANSI | DMGL_PARAMS); |
| if (demangled_name != NULL) |
| { |
| info->enclosing_symbol_name.assign(demangled_name); |
| free(demangled_name); |
| } |
| } |
| } |
| return true; |
| } |
| } |
| |
| return false; |
| } |
| |
| // Look for a kept section corresponding to the given discarded section, |
| // and return its outpu
|