X-Git-Url: http://review.tizen.org/git/?a=blobdiff_plain;f=gold%2Fobject.cc;h=e357ddf8707dc0908cfb6ab7f581b4b3281eb14c;hb=ee959deb576c46b85b6174626d700e1393256adf;hp=956366cdf0ac1c4d7959a0204086bc1203188212;hpb=f0641a0b382db7403f04fab3d4e8fac25a2b68af;p=platform%2Fupstream%2Fbinutils.git diff --git a/gold/object.cc b/gold/object.cc index 956366c..e357ddf 100644 --- a/gold/object.cc +++ b/gold/object.cc @@ -1,245 +1,881 @@ // object.cc -- support for an object file for linking in gold +// Copyright (C) 2006-2014 Free Software Foundation, Inc. +// Written by Ian Lance Taylor . + +// 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 #include -#include +#include +#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" 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 +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(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 +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::shdr_size)); + typename elfcpp::Shdr 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 +void +Object::read_section_data(elfcpp::Elf_file* elf_file, + Read_symbols_data* sd) +{ + const int shdr_size = elfcpp::Elf_sizes::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 shdrnames(pshdrnames); + + if (shdrnames.get_sh_type() != elfcpp::SHT_STRTAB) + this->error(_("section name section has wrong type: %u"), + static_cast(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(warning); + len = strlen(warning); + } + std::string warning(reinterpret_cast(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 + +// 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); +} + // Class Sized_relobj. +// Iterate over local symbols, calling a visitor class V for each GOT offset +// associated with a local symbol. + +template +void +Sized_relobj::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_offsets::const_iterator p = this->local_got_offsets_.find(i); + 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 +uint64_t +Sized_relobj::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 -Sized_relobj::Sized_relobj( +Sized_relobj_file::Sized_relobj_file( const std::string& name, Input_file* input_file, off_t offset, const elfcpp::Ehdr& ehdr) - : Relobj(name, input_file, offset), - section_headers_(NULL), - flags_(ehdr.get_e_flags()), - shoff_(ehdr.get_e_shoff()), - shstrndx_(0), - symtab_shnum_(0), + : Sized_relobj(name, input_file, offset), + elf_file_(this, ehdr), + symtab_shndx_(-1U), local_symbol_count_(0), output_local_symbol_count_(0), - symbols_(NULL), + output_local_dynsym_count_(0), + symbols_(), + defined_count_(0), local_symbol_offset_(0), - values_(NULL) + local_dynsym_offset_(0), + local_values_(), + local_plt_offsets_(), + kept_comdat_sections_(), + has_eh_frame_(false), + discarded_eh_frame_shndx_(-1U), + is_deferred_layout_(false), + deferred_layout_(), + deferred_layout_relocs_(), + compressed_sections_() { - if (ehdr.get_e_ehsize() != This::ehdr_size) - { - fprintf(stderr, _("%s: %s: bad e_ehsize field (%d != %d)\n"), - program_name, this->name().c_str(), ehdr.get_e_ehsize(), - This::ehdr_size); - gold_exit(false); - } - if (ehdr.get_e_shentsize() != This::shdr_size) - { - fprintf(stderr, _("%s: %s: bad e_shentsize field (%d != %d)\n"), - program_name, this->name().c_str(), ehdr.get_e_shentsize(), - This::shdr_size); - gold_exit(false); - } + this->e_type_ = ehdr.get_e_type(); } template -Sized_relobj::~Sized_relobj() +Sized_relobj_file::~Sized_relobj_file() { } -// Read the section header for section SHNUM. +// Set up an object file based on the file header. This sets up the +// section information. template -inline const unsigned char* -Sized_relobj::section_header(unsigned int shnum) +void +Sized_relobj_file::do_setup() { - assert(shnum < this->shnum()); - off_t symtabshdroff = this->shoff_ + shnum * This::shdr_size; - return this->get_view(symtabshdroff, This::shdr_size); + const unsigned int shnum = this->elf_file_.shnum(); + this->set_shnum(shnum); } -// Return the name of section SHNUM. The object must already be -// locked. +// 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 -std::string -Sized_relobj::do_section_name(unsigned int shnum) +void +Sized_relobj_file::find_symtab(const unsigned char* pshdrs) { - // Read the section names. - typename This::Shdr shdrnames(this->section_header(this->shstrndx_)); - const unsigned char* pnamesu = this->get_view(shdrnames.get_sh_offset(), - shdrnames.get_sh_size()); - const char* pnames = reinterpret_cast(pnamesu); - - typename This::Shdr shdr(this->section_header(shnum)); - if (shdr.get_sh_name() >= shdrnames.get_sh_size()) + const unsigned int shnum = this->shnum(); + this->symtab_shndx_ = 0; + if (shnum > 0) { - fprintf(stderr, - _("%s: %s: bad section name offset for section %u: %lu\n"), - program_name, this->name().c_str(), shnum, - static_cast(shdr.get_sh_name())); - gold_exit(false); + // 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(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 +Xindex* +Sized_relobj_file::do_initialize_xindex() +{ + gold_assert(this->symtab_shndx_ != -1U); + Xindex* xindex = new Xindex(this->elf_file_.large_shndx_offset()); + xindex->initialize_symtab_xindex(this, this->symtab_shndx_); + return xindex; +} - return std::string(pnames + shdr.get_sh_name()); +// Return whether SHDR has the right type and flags to be a GNU +// .eh_frame section. + +template +bool +Sized_relobj_file::check_eh_frame_flags( + const elfcpp::Shdr* shdr) const +{ + elfcpp::Elf_Word sh_type = shdr->get_sh_type(); + return ((sh_type == elfcpp::SHT_PROGBITS + || sh_type == elfcpp::SHT_X86_64_UNWIND) + && (shdr->get_sh_flags() & elfcpp::SHF_ALLOC) != 0); } -// Return a view of the contents of section SHNUM. The object does -// not have to be locked. +// Find the section header with the given name. template const unsigned char* -Sized_relobj::do_section_contents(unsigned int shnum, - off_t* plen) +Object::find_shdr( + const unsigned char* pshdrs, + const char* name, + const char* names, + section_size_type names_size, + const unsigned char* hdr) const { - Task_locker_obj tl(*this); + const int shdr_size = elfcpp::Elf_sizes::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 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(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; + } - typename This::Shdr shdr(this->section_header(shnum)); - *plen = shdr.get_sh_size(); - return this->get_view(shdr.get_sh_offset(), shdr.get_sh_size()); + hdr += shdr_size; + while (hdr < hdr_end) + { + typename elfcpp::Shdr shdr(hdr); + if (shdr.get_sh_name() == sh_name) + return hdr; + hdr += shdr_size; + } + hdr = NULL; + if (sh_name == 0) + return hdr; + } } -// Set up an object file bsaed on the file header. This sets up the -// target and reads the section information. +// Return whether there is a GNU .eh_frame section, given the section +// headers and the section names. template -void -Sized_relobj::setup( - const elfcpp::Ehdr& ehdr) +bool +Sized_relobj_file::find_eh_frame( + const unsigned char* pshdrs, + const char* names, + section_size_type names_size) const { - int machine = ehdr.get_e_machine(); - Target* target = select_target(machine, size, big_endian, - ehdr.get_e_ident()[elfcpp::EI_OSABI], - ehdr.get_e_ident()[elfcpp::EI_ABIVERSION]); - if (target == NULL) + const unsigned char* s = NULL; + + while (1) { - fprintf(stderr, _("%s: %s: unsupported ELF machine number %d\n"), - program_name, this->name().c_str(), machine); - gold_exit(false); + s = this->template find_shdr(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; } - this->set_target(target); +} + +// 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(), so we know +// that the section name begins with ".zdebug". - unsigned int shnum = ehdr.get_e_shnum(); - unsigned int shstrndx = ehdr.get_e_shstrndx(); - if ((shnum == 0 || shstrndx == elfcpp::SHN_XINDEX) - && this->shoff_ != 0) +static bool +need_decompressed_section(const char* name) +{ + // Skip over the ".zdebug" and a quick check for the "_". + name += 7; + if (*name++ != '_') + return false; + +#ifdef ENABLE_THREADS + // Decompressing these sections now will help only if we're + // multithreaded. + if (parameters->options().threads()) { - typename This::Shdr shdr(this->section_header(0)); - if (shnum == 0) - shnum = shdr.get_sh_size(); - if (shstrndx == elfcpp::SHN_XINDEX) - shstrndx = shdr.get_sh_link(); + // 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; } - this->set_shnum(shnum); - this->shstrndx_ = shstrndx; +#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; - if (shnum == 0) - return; + return false; +} - // We store the section headers in a File_view until do_read_symbols. - this->section_headers_ = this->get_lasting_view(this->shoff_, - shnum * This::shdr_size); +// Build a table for any compressed debug sections, mapping each section index +// to the uncompressed size and (if needed) the decompressed contents. - // Find the SHT_SYMTAB section. 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. - const unsigned char* p = this->section_headers_->data(); +template +Compressed_section_map* +build_compressed_section_map( + const unsigned char* pshdrs, + unsigned int shnum, + const char* names, + section_size_type names_size, + Sized_relobj_file* obj) +{ + Compressed_section_map* uncompressed_map = new Compressed_section_map(); + const unsigned int shdr_size = elfcpp::Elf_sizes::shdr_size; + const unsigned char* p = pshdrs + shdr_size; - // Skip the first section, which is always empty. - p += This::shdr_size; - for (unsigned int i = 1; i < shnum; ++i, p += This::shdr_size) + for (unsigned int i = 1; i < shnum; ++i, p += shdr_size) { - typename This::Shdr shdr(p); - if (shdr.get_sh_type() == elfcpp::SHT_SYMTAB) + typename elfcpp::Shdr shdr(p); + if (shdr.get_sh_type() == elfcpp::SHT_PROGBITS + && (shdr.get_sh_flags() & elfcpp::SHF_ALLOC) == 0) { - this->symtab_shnum_ = i; - break; + if (shdr.get_sh_name() >= names_size) + { + obj->error(_("bad section name offset for section %u: %lu"), + i, static_cast(shdr.get_sh_name())); + continue; + } + + const char* name = names + shdr.get_sh_name(); + if (is_compressed_debug_section(name)) + { + section_size_type len; + const unsigned char* contents = + obj->section_contents(i, &len, false); + uint64_t uncompressed_size = get_uncompressed_size(contents, len); + Compressed_section_info info; + info.size = convert_to_section_size_type(uncompressed_size); + info.contents = NULL; + if (uncompressed_size != -1ULL) + { + unsigned char* uncompressed_data = NULL; + if (need_decompressed_section(name)) + { + uncompressed_data = new unsigned char[uncompressed_size]; + if (decompress_input_section(contents, len, + uncompressed_data, + uncompressed_size)) + 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 +bool +Sized_relobj_file::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(namesu); + + if (this->find_eh_frame(pshdrs, names, sd->section_names_size)) + this->has_eh_frame_ = true; + + if (memmem(names, sd->section_names_size, ".zdebug_", 8) != NULL) + this->compressed_sections_ + = build_compressed_section_map(pshdrs, this->shnum(), names, + sd->section_names_size, this); + return (this->has_eh_frame_ + || (!parameters->options().relocatable() + && parameters->options().gdb_index() + && (memmem(names, sd->section_names_size, "debug_info", 12) == 0 + || memmem(names, sd->section_names_size, "debug_types", + 13) == 0))); } // Read the sections and symbols from an object file. template void -Sized_relobj::do_read_symbols(Read_symbols_data* sd) +Sized_relobj_file::do_read_symbols(Read_symbols_data* sd) { - // Transfer our view of the section headers to SD. - sd->section_headers = this->section_headers_; - this->section_headers_ = NULL; + this->base_read_symbols(sd); +} - // Read the section names. - const unsigned char* pshdrs = sd->section_headers->data(); - const unsigned char* pshdrnames = pshdrs + this->shstrndx_ * This::shdr_size; - typename This::Shdr shdrnames(pshdrnames); - sd->section_names_size = shdrnames.get_sh_size(); - sd->section_names = this->get_lasting_view(shdrnames.get_sh_offset(), - sd->section_names_size); +// Read the sections and symbols from an object file. This is common +// code for all target-specific overrides of do_read_symbols(). + +template +void +Sized_relobj_file::base_read_symbols(Read_symbols_data* sd) +{ + this->read_section_data(&this->elf_file_, sd); - if (this->symtab_shnum_ == 0) + 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. - sd->symbols = NULL; - sd->symbols_size = 0; - sd->symbol_names = NULL; - sd->symbol_names_size = 0; return; } // Get the symbol table section header. typename This::Shdr symtabshdr(pshdrs - + this->symtab_shnum_ * This::shdr_size); - assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB); + + 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. - // We only need the external symbols. const int sym_size = This::sym_size; const unsigned int loccount = symtabshdr.get_sh_info(); this->local_symbol_count_ = loccount; - off_t locsize = loccount * sym_size; - off_t extoff = symtabshdr.get_sh_offset() + locsize; - off_t extsize = symtabshdr.get_sh_size() - locsize; + 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; + } - // Read the symbol table. - File_view* fvsymtab = this->get_lasting_view(extoff, extsize); + File_view* fvsymtab = this->get_lasting_view(readoff, readsize, true, false); // Read the section header for the symbol names. - unsigned int shnum = this->shnum(); - unsigned int strtab_shnum = symtabshdr.get_sh_link(); - if (strtab_shnum == 0 || strtab_shnum >= shnum) + unsigned int strtab_shndx = this->adjust_shndx(symtabshdr.get_sh_link()); + if (strtab_shndx >= this->shnum()) { - fprintf(stderr, _("%s: %s: invalid symbol table name index: %u\n"), - program_name, this->name().c_str(), strtab_shnum); - gold_exit(false); + this->error(_("invalid symbol table name index: %u"), strtab_shndx); + return; } - typename This::Shdr strtabshdr(pshdrs + strtab_shnum * This::shdr_size); + typename This::Shdr strtabshdr(pshdrs + strtab_shndx * This::shdr_size); if (strtabshdr.get_sh_type() != elfcpp::SHT_STRTAB) { - fprintf(stderr, - _("%s: %s: symbol table name section has wrong type: %u\n"), - program_name, this->name().c_str(), - static_cast(strtabshdr.get_sh_type())); - gold_exit(false); + this->error(_("symbol table name section has wrong type: %u"), + static_cast(strtabshdr.get_sh_type())); + return; } // Read the symbol names. File_view* fvstrtab = this->get_lasting_view(strtabshdr.get_sh_offset(), - strtabshdr.get_sh_size()); + strtabshdr.get_sh_size(), + false, true); sd->symbols = fvsymtab; - sd->symbols_size = extsize; + sd->symbols_size = readsize; + sd->external_symbols_offset = need_local_symbols ? locsize : 0; sd->symbol_names = fvstrtab; - sd->symbol_names_size = strtabshdr.get_sh_size(); + 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 +unsigned int +Sized_relobj_file::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 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 @@ -250,15 +886,20 @@ Sized_relobj::do_read_symbols(Read_symbols_data* sd) template bool -Sized_relobj::include_section_group( +Sized_relobj_file::include_section_group( + Symbol_table* symtab, Layout* layout, unsigned int index, - const elfcpp::Shdr& shdr, + const char* name, + const unsigned char* shdrs, + const char* section_names, + section_size_type section_names_size, std::vector* 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()); + shdr.get_sh_size(), true, false); const elfcpp::Elf_Word* pword = reinterpret_cast(pcon); @@ -266,113 +907,187 @@ Sized_relobj::include_section_group( // 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); - if ((flags & elfcpp::GRP_COMDAT) == 0) - return true; - // Look up the group signature, which is the name of a symbol. This - // is a lot of effort to go to to read a string. Why didn't they - // just use the name of the SHT_GROUP section as the group - // signature? + // 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). - if (shdr.get_sh_link() >= this->shnum()) - { - fprintf(stderr, _("%s: %s: section group %u link %u out of range\n"), - program_name, this->name().c_str(), index, shdr.get_sh_link()); - gold_exit(false); - } - - typename This::Shdr symshdr(this->section_header(shdr.get_sh_link())); + 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. - if (shdr.get_sh_info() >= symshdr.get_sh_size() / This::sym_size) + unsigned int symndx = shdr.get_sh_info(); + if (symndx >= symshdr.get_sh_size() / This::sym_size) { - fprintf(stderr, _("%s: %s: section group %u info %u out of range\n"), - program_name, this->name().c_str(), index, shdr.get_sh_info()); - gold_exit(false); + this->error(_("section group %u info %u out of range"), + index, symndx); + return false; } - off_t symoff = symshdr.get_sh_offset() + shdr.get_sh_info() * This::sym_size; - const unsigned char* psym = this->get_view(symoff, This::sym_size); + 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 sym(psym); - // Read the section header for the symbol table names. - if (symshdr.get_sh_link() >= this->shnum()) - { - fprintf(stderr, _("%s; %s: symtab section %u link %u out of range\n"), - program_name, this->name().c_str(), shdr.get_sh_link(), - symshdr.get_sh_link()); - gold_exit(false); - } - - typename This::Shdr symnamehdr(this->section_header(symshdr.get_sh_link())); - // Read the symbol table names. - const unsigned char *psymnamesu = this->get_view(symnamehdr.get_sh_offset(), - symnamehdr.get_sh_size()); + 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(psymnamesu); // Get the section group signature. - if (sym.get_st_name() >= symnamehdr.get_sh_size()) + if (sym.get_st_name() >= symnamelen) { - fprintf(stderr, _("%s: %s: symbol %u name offset %u out of range\n"), - program_name, this->name().c_str(), shdr.get_sh_info(), - sym.get_st_name()); - gold_exit(false); + this->error(_("symbol %u name offset %u out of range"), + symndx, sym.get_st_name()); + return false; } - const char* signature = psymnames + sym.get_st_name(); + 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. - // FIXME. - if (signature[0] == '\0' - && sym.get_st_type() == elfcpp::STT_SECTION - && sym.get_st_shndx() < this->shnum()) + if (signature[0] == '\0' && sym.get_st_type() == elfcpp::STT_SECTION) { - typename This::Shdr shdrnames(this->section_header(this->shstrndx_)); - const unsigned char* pnamesu = this->get_view(shdrnames.get_sh_offset(), - shdrnames.get_sh_size()); - const char* pnames = reinterpret_cast(pnamesu); - - typename This::Shdr sechdr(this->section_header(sym.get_st_shndx())); - if (sechdr.get_sh_name() >= shdrnames.get_sh_size()) + 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()) { - fprintf(stderr, - _("%s: %s: bad section name offset for section %u: %lu\n"), - program_name, this->name().c_str(), sym.get_st_shndx(), - static_cast(sechdr.get_sh_name())); - gold_exit(false); + this->error(_("symbol %u invalid section index %u"), + symndx, sym_shndx); + return false; } - - signature = pnames + sechdr.get_sh_name(); + 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, and see whether we've already seen one - // with the same signature. - if (layout->add_comdat(signature, true)) - return true; + // 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; - // This is a duplicate. We want to discard the sections in this - // group. - size_t count = shdr.get_sh_size() / sizeof(elfcpp::Elf_Word); - for (size_t i = 1; i < count; ++i) + if ((flags & elfcpp::GRP_COMDAT) == 0) { - elfcpp::Elf_Word secnum = - elfcpp::Swap<32, big_endian>::readval(pword + i); - if (secnum >= this->shnum()) - { - fprintf(stderr, - _("%s: %s: section %u in section group %u out of range"), - program_name, this->name().c_str(), secnum, - index); - gold_exit(false); - } - (*omit)[secnum] = true; + include_group = true; + is_comdat = false; } - - return 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 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; + + if (is_comdat) + { + Relobj* kept_object = kept_section->object(); + if (kept_section->is_comdat()) + { + // Find the corresponding kept section, and store + // that info in the discarded section table. + unsigned int kept_shndx; + uint64_t kept_size; + if (kept_section->find_comdat_section(mname, &kept_shndx, + &kept_size)) + { + // We don't keep a mapping for this section if + // it has a different size. The mapping is only + // used for relocation processing, and we don't + // want to treat the sections as similar if the + // sizes are different. Checking the section + // size is the approach used by the GNU linker. + if (kept_size == member_shdr.get_sh_size()) + this->set_kept_comdat_section(shndx, kept_object, + kept_shndx); + } + } + else + { + // The existing section is a linkonce section. Add + // a mapping if there is exactly one section in the + // group (which is true when COUNT == 2) and if it + // is the same size. + if (count == 2 + && (kept_section->linkonce_size() + == member_shdr.get_sh_size())) + this->set_kept_comdat_section(shndx, kept_object, + kept_section->shndx()); + } + } + } + } + + 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 @@ -392,375 +1107,1946 @@ Sized_relobj::include_section_group( template bool -Sized_relobj::include_linkonce_section( +Sized_relobj_file::include_linkonce_section( Layout* layout, + unsigned int index, const char* name, - const elfcpp::Shdr&) + const elfcpp::Shdr& shdr) { - const char* symname = strrchr(name, '.') + 1; - bool include1 = layout->add_comdat(symname, false); - bool include2 = layout->add_comdat(name, true); + typename elfcpp::Elf_types::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() + && kept2->linkonce_size() == sh_size) + this->set_kept_comdat_section(index, kept2->object(), kept2->shndx()); + } + 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. + unsigned int kept_shndx; + uint64_t kept_size; + if (kept1->object() != NULL + && kept1->is_comdat() + && kept1->find_single_comdat_section(&kept_shndx, &kept_size) + && kept_size == sh_size) + this->set_kept_comdat_section(index, kept1->object(), kept_shndx); + } + else + { + kept1->set_linkonce_size(sh_size); + kept2->set_linkonce_size(sh_size); + } + return include1 && include2; } +// Layout an input section. + +template +inline void +Sized_relobj_file::layout_section( + Layout* layout, + unsigned int shndx, + const char* name, + const typename This::Shdr& shdr, + unsigned int reloc_shndx, + unsigned int reloc_type) +{ + off_t offset; + Output_section* os = layout->layout(this, shndx, name, shdr, + 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(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 +void +Sized_relobj_file::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) + { + // An object can contain at most one section holding exception + // frame information. + gold_assert(this->discarded_eh_frame_shndx_ == -1U); + this->discarded_eh_frame_shndx_ = shndx; + this->section_offsets()[shndx] = invalid_address; + } + else + this->section_offsets()[shndx] = convert_types(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(); +} + // 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=): 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 void -Sized_relobj::do_layout(const General_options& options, - Symbol_table* symtab, - Layout* layout, - Read_symbols_data* sd) +Sized_relobj_file::do_layout(Symbol_table* symtab, + Layout* layout, + Read_symbols_data* sd) { - unsigned int shnum = this->shnum(); + 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* pshdrs = sd->section_headers->data(); + const unsigned char* shdrs = section_headers_data; + const unsigned char* pshdrs; // Get the section names. - const unsigned char* pnamesu = sd->section_names->data(); + const unsigned char* pnamesu = (is_two_pass + ? gc_sd->section_names_data + : sd->section_names->data()); + const char* pnames = reinterpret_cast(pnamesu); - std::vector& map_sections(this->map_to_output()); - map_sections.resize(shnum); + // 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 reloc_shndx(shnum, 0); + std::vector 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
& 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 omit(shnum, false); - const char warn_prefix[] = ".gnu.warning."; - const int warn_prefix_len = sizeof warn_prefix - 1; + // 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 reloc_sections; + + // Keep track of .eh_frame sections. + std::vector eh_frame_sections; + + // Keep track of .debug_info and .debug_types sections. + std::vector debug_info_sections; + std::vector debug_types_sections; // Skip the first, dummy, section. - pshdrs += This::shdr_size; + pshdrs = shdrs + This::shdr_size; for (unsigned int i = 1; i < shnum; ++i, pshdrs += This::shdr_size) { typename This::Shdr shdr(pshdrs); - if (shdr.get_sh_name() >= sd->section_names_size) + if (shdr.get_sh_name() >= section_names_size) { - fprintf(stderr, - _("%s: %s: bad section name offset for section %u: %lu\n"), - program_name, this->name().c_str(), i, - static_cast(shdr.get_sh_name())); - gold_exit(false); + this->error(_("bad section name offset for section %u: %lu"), + i, static_cast(shdr.get_sh_name())); + return; } const char* name = pnames + shdr.get_sh_name(); - if (strncmp(name, warn_prefix, warn_prefix_len) == 0) + 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; + } + + bool discard = omit[i]; + if (!discard) + { + if (shdr.get_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(shdr.get_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) + || shdr.get_sh_type() == elfcpp::SHT_INIT_ARRAY + || shdr.get_sh_type() == elfcpp::SHT_FINI_ARRAY) + { + symtab->gc()->worklist().push(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 + && (shdr.get_sh_type() == elfcpp::SHT_REL + || shdr.get_sh_type() == elfcpp::SHT_RELA)) + { + reloc_sections.push_back(i); + continue; + } + + if (relocatable && shdr.get_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 (!relocatable + && strcmp(name, ".eh_frame") == 0 + && this->check_eh_frame_flags(&shdr)) + { + if (is_pass_one) + { + if (this->is_deferred_layout()) + out_sections[i] = reinterpret_cast(2); + else + out_sections[i] = reinterpret_cast(1); + out_section_offsets[i] = invalid_address; + } + else if (this->is_deferred_layout()) + this->deferred_layout_.push_back(Deferred_layout(i, name, + pshdrs, + reloc_shndx[i], + reloc_type[i])); + else + eh_frame_sections.push_back(i); + continue; + } + + if (is_pass_two && parameters->options().gc_sections()) { - symtab->add_warning(name + warn_prefix_len, this, i); - if (!options.is_relocatable()) - omit[i] = true; + // 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; + } } - bool discard = omit[i]; - if (!discard) + if (is_pass_two && parameters->options().icf_enabled()) { - if (shdr.get_sh_type() == elfcpp::SHT_GROUP) + if (out_sections[i] == NULL) { - if (!this->include_section_group(layout, i, shdr, &omit)) - discard = true; + gold_assert(out_section_offsets[i] == invalid_address); + continue; } - else if (Layout::is_linkonce(name)) + 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(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, + 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(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(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(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, 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 (!this->include_linkonce_section(layout, name, shdr)) - discard = true; + 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); } } + } + + if (!is_pass_two) + 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::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::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(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, pshdr, 0, elfcpp::SHT_NULL)); + out_sections[i] = reinterpret_cast(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::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::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 +void +Sized_relobj_file::do_layout_deferred_sections(Layout* layout) +{ + typename std::vector::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, 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
& 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 +void +Sized_relobj_file::do_add_symbols(Symbol_table* symtab, + Read_symbols_data* sd, + 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); + + const char* sym_names = + reinterpret_cast(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 +Archive::Should_include +Sized_relobj_file::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(sd->symbol_names->data()); + const unsigned char* syms = + sd->symbols->data() + sd->external_symbols_offset; + const int sym_size = elfcpp::Elf_sizes::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 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 +void +Sized_relobj_file::do_for_all_global_symbols( + Read_symbols_data* sd, + Library_base::Symbol_visitor_base* v) +{ + const char* sym_names = + reinterpret_cast(sd->symbol_names->data()); + const unsigned char* syms = + sd->symbols->data() + sd->external_symbols_offset; + const int sym_size = elfcpp::Elf_sizes::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 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 +bool +Sized_relobj_file::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 +unsigned int +Sized_relobj_file::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 +void +Sized_relobj_file::set_local_plt_offset( + unsigned int symndx, unsigned int plt_offset) +{ + std::pair 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 +void +Sized_relobj_file::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(pnamesu); + + // Loop over the local symbols. + + const Output_sections& out_sections(this->output_sections()); + 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(); + for (unsigned int i = 1; i < loccount; ++i, psyms += sym_size) + { + elfcpp::Sym sym(psyms); + + Symbol_value& 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 ((shndx < shnum && out_sections[shndx] == NULL) + || shndx == this->discarded_eh_frame_shndx_) + { + 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(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; + } + + // 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 + && 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 +typename Sized_relobj_file::Compute_final_local_value_status +Sized_relobj_file::compute_final_local_value_internal( + unsigned int r_sym, + const Symbol_value* lv_in, + Symbol_value* lv_out, + bool relocatable, + const Output_sections& out_sections, + const std::vector
& 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* folded_obj = reinterpret_cast + *>(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 (shndx == this->discarded_eh_frame_shndx_) + { + // This local symbol belongs to a discarded .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. + lv_out->set_output_value( + os->output_address(this, shndx, lv_in->input_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) + { + Address relocatable_link_adjustment = + relocatable ? os->address() : 0; + lv_out->set_output_value(posd->address() + - relocatable_link_adjustment); + } + 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* msv = + new Merged_symbol_value(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 +typename Sized_relobj_file::Compute_final_local_value_status +Sized_relobj_file::compute_final_local_value( + unsigned int r_sym, + const Symbol_value* lv_in, + Symbol_value* 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
& 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 +unsigned int +Sized_relobj_file::do_finalize_local_symbols( + unsigned int index, + off_t off, + Symbol_table* symtab) +{ + gold_assert(off == static_cast(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
& out_offsets(this->section_offsets()); + + for (unsigned int i = 1; i < loccount; ++i) + { + Symbol_value* 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; + } + 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 +unsigned int +Sized_relobj_file::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& 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 +unsigned int +Sized_relobj_file::do_set_local_dynsym_offset(off_t off) +{ + gold_assert(off == static_cast(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 +uint64_t +Sized_relobj_file::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 +uint64_t +Sized_relobj_file::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 +void +Sized_relobj_file::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(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 isym(psyms); + + Symbol_value& 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 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(this->local_values_[i].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; + } - if (discard) + // Write the symbol to the output dynamic symbol table. + if (lv.has_output_dynsym_entry()) { - // Do not include this section in the link. - map_sections[i].output_section = NULL; - continue; + gold_assert(dyn_ov < dyn_oview + dyn_output_size); + elfcpp::Sym_write 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(this->local_values_[i].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; } - - off_t offset; - Output_section* os = layout->layout(this, i, name, shdr, &offset); - - map_sections[i].output_section = os; - map_sections[i].offset = offset; } - delete sd->section_headers; - sd->section_headers = NULL; - delete sd->section_names; - sd->section_names = NULL; -} - -// Add the symbols to the symbol table. -template -void -Sized_relobj::do_add_symbols(Symbol_table* symtab, - Read_symbols_data* sd) -{ - if (sd->symbols == NULL) + if (output_size > 0) { - assert(sd->symbol_names == NULL); - return; + gold_assert(ov - oview == output_size); + of->write_output_view(symtab_off + this->local_symbol_offset_, + output_size, oview); } - const int sym_size = This::sym_size; - size_t symcount = sd->symbols_size / sym_size; - if (symcount * sym_size != sd->symbols_size) + if (dyn_output_size > 0) { - fprintf(stderr, - _("%s: %s: size of symbols is not multiple of symbol size\n"), - program_name, this->name().c_str()); - gold_exit(false); + gold_assert(dyn_ov - dyn_oview == dyn_output_size); + of->write_output_view(this->local_dynsym_offset_, dyn_output_size, + dyn_oview); } - - this->symbols_ = new Symbol*[symcount]; - - const char* sym_names = - reinterpret_cast(sd->symbol_names->data()); - symtab->add_from_object(this, sd->symbols->data(), - symcount, sym_names, - sd->symbol_names_size, - this->symbols_); - - delete sd->symbols; - sd->symbols = NULL; - delete sd->symbol_names; - sd->symbol_names = NULL; } -// Finalize the local symbols. Here we record the file offset at -// which they should be output, we add their names to *POOL, and we -// add their values to THIS->VALUES_. Return the new file offset. -// This function is always called from the main thread. The actual -// output of the local symbols will occur in a separate task. +// 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 -off_t -Sized_relobj::do_finalize_local_symbols(off_t off, - Stringpool* pool) +bool +Sized_relobj_file::get_symbol_location_info( + unsigned int shndx, + off_t offset, + Symbol_location_info* info) { - if (this->symtab_shnum_ == 0) - { - // This object has no symbols. Weird but legal. - return off; - } + if (this->symtab_shndx_ == 0) + return false; - off = align_address(off, size >> 3); + section_size_type symbols_size; + const unsigned char* symbols = this->section_contents(this->symtab_shndx_, + &symbols_size, + false); - this->local_symbol_offset_ = off; - - // Read the symbol table section header. - typename This::Shdr symtabshdr(this->section_header(this->symtab_shnum_)); - assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB); + 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(symbol_names_u); - // Read the local symbols. const int sym_size = This::sym_size; - const unsigned int loccount = this->local_symbol_count_; - assert(loccount == symtabshdr.get_sh_info()); - off_t locsize = loccount * sym_size; - const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(), - locsize); - - this->values_ = new typename elfcpp::Elf_types::Elf_Addr[loccount]; - - // Read the section header for the symbol names. - typename This::Shdr strtabshdr( - this->section_header(symtabshdr.get_sh_link())); - assert(strtabshdr.get_sh_type() == elfcpp::SHT_STRTAB); - - // Read the symbol names. - const unsigned char* pnamesu = this->get_view(strtabshdr.get_sh_offset(), - strtabshdr.get_sh_size()); - const char* pnames = reinterpret_cast(pnamesu); - - // Loop over the local symbols. + const size_t count = symbols_size / sym_size; - std::vector& mo(this->map_to_output()); - unsigned int shnum = this->shnum(); - unsigned int count = 0; - // Skip the first, dummy, symbol. - psyms += sym_size; - for (unsigned int i = 1; i < loccount; ++i, psyms += sym_size) + const unsigned char* p = symbols; + for (size_t i = 0; i < count; ++i, p += sym_size) { - elfcpp::Sym sym(psyms); - - unsigned int shndx = sym.get_st_shndx(); + elfcpp::Sym sym(p); - if (shndx >= elfcpp::SHN_LORESERVE) + if (sym.get_st_type() == elfcpp::STT_FILE) { - if (shndx == elfcpp::SHN_ABS) - this->values_[i] = sym.get_st_value(); + if (sym.get_st_name() >= names_size) + info->source_file = "(invalid)"; else - { - // FIXME: Handle SHN_XINDEX. - fprintf(stderr, - _("%s: %s: unknown section index %u " - "for local symbol %u\n"), - program_name, this->name().c_str(), shndx, i); - gold_exit(false); - } + info->source_file = symbol_names + sym.get_st_name(); + continue; } - else + + 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(sym.get_st_value()) <= offset + && (static_cast(sym.get_st_value() + sym.get_st_size()) + > offset)) { - if (shndx >= shnum) + info->enclosing_symbol_type = sym.get_st_type(); + if (sym.get_st_name() > names_size) + info->enclosing_symbol_name = "(invalid)"; + else { - fprintf(stderr, - _("%s: %s: local symbol %u section index %u " - "out of range\n"), - program_name, this->name().c_str(), i, shndx); - gold_exit(false); + 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; + } + } - if (mo[shndx].output_section == NULL) - { - this->values_[i] = 0; - continue; - } + return false; +} - this->values_[i] = (mo[shndx].output_section->address() - + mo[shndx].offset - + sym.get_st_value()); - } +// Look for a kept section corresponding to the given discarded section, +// and return its output address. This is used only for relocations in +// debugging sections. If we can't find the kept section, return 0. - if (sym.get_st_type() != elfcpp::STT_SECTION) +template +typename Sized_relobj_file::Address +Sized_relobj_file::map_to_kept_section( + unsigned int shndx, + bool* found) const +{ + Relobj* kept_object; + unsigned int kept_shndx; + if (this->get_kept_comdat_section(shndx, &kept_object, &kept_shndx)) + { + Sized_relobj_file* kept_relobj = + static_cast*>(kept_object); + Output_section* os = kept_relobj->output_section(kept_shndx); + Address offset = kept_relobj->get_output_section_offset(kept_shndx); + if (os != NULL && offset != invalid_address) { - pool->add(pnames + sym.get_st_name(), NULL); - off += sym_size; - ++count; + *found = true; + return os->address() + offset; } } + *found = false; + return 0; +} - this->output_local_symbol_count_ = count; +// Get symbol counts. - return off; +template +void +Sized_relobj_file::do_get_global_symbol_counts( + const Symbol_table*, + size_t* defined, + size_t* used) const +{ + *defined = this->defined_count_; + size_t count = 0; + for (typename Symbols::const_iterator p = this->symbols_.begin(); + p != this->symbols_.end(); + ++p) + if (*p != NULL + && (*p)->source() == Symbol::FROM_OBJECT + && (*p)->object() == this + && (*p)->is_defined()) + ++count; + *used = count; } -// Write out the local symbols. +// Return a view of the decompressed contents of a section. Set *PLEN +// to the size. Set *IS_NEW to true if the contents need to be freed +// by the caller. template -void -Sized_relobj::write_local_symbols(Output_file* of, - const Stringpool* sympool) +const unsigned char* +Sized_relobj_file::do_decompressed_section_contents( + unsigned int shndx, + section_size_type* plen, + bool* is_new) { - if (this->symtab_shnum_ == 0) + section_size_type buffer_size; + const unsigned char* buffer = this->do_section_contents(shndx, &buffer_size, + false); + + if (this->compressed_sections_ == NULL) { - // This object has no symbols. Weird but legal. - return; + *plen = buffer_size; + *is_new = false; + return buffer; } - // Read the symbol table section header. - typename This::Shdr symtabshdr(this->section_header(this->symtab_shnum_)); - assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB); - const unsigned int loccount = this->local_symbol_count_; - 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); + Compressed_section_map::const_iterator p = + this->compressed_sections_->find(shndx); + if (p == this->compressed_sections_->end()) + { + *plen = buffer_size; + *is_new = false; + return buffer; + } - // Read the section header for the symbol names. - typename This::Shdr strtabshdr( - this->section_header(symtabshdr.get_sh_link())); - assert(strtabshdr.get_sh_type() == elfcpp::SHT_STRTAB); + section_size_type uncompressed_size = p->second.size; + if (p->second.contents != NULL) + { + *plen = uncompressed_size; + *is_new = false; + return p->second.contents; + } - // Read the symbol names. - const unsigned char* pnamesu = this->get_view(strtabshdr.get_sh_offset(), - strtabshdr.get_sh_size()); - const char* pnames = reinterpret_cast(pnamesu); + unsigned char* uncompressed_data = new unsigned char[uncompressed_size]; + if (!decompress_input_section(buffer, + buffer_size, + uncompressed_data, + uncompressed_size)) + this->error(_("could not decompress section %s"), + this->do_section_name(shndx).c_str()); + + // We could cache the results in p->second.contents and store + // false in *IS_NEW, but build_compressed_section_map() would + // have done so if it had expected it to be profitable. If + // we reach this point, we expect to need the contents only + // once in this pass. + *plen = uncompressed_size; + *is_new = true; + return uncompressed_data; +} - // Get a view into the output file. - off_t output_size = this->output_local_symbol_count_ * sym_size; - unsigned char* oview = of->get_output_view(this->local_symbol_offset_, - output_size); +// Discard any buffers of uncompressed sections. This is done +// at the end of the Add_symbols task. - std::vector& mo(this->map_to_output()); +template +void +Sized_relobj_file::do_discard_decompressed_sections() +{ + if (this->compressed_sections_ == NULL) + return; - psyms += sym_size; - unsigned char* ov = oview; - for (unsigned int i = 1; i < loccount; ++i, psyms += sym_size) + for (Compressed_section_map::iterator p = this->compressed_sections_->begin(); + p != this->compressed_sections_->end(); + ++p) { - elfcpp::Sym isym(psyms); + if (p->second.contents != NULL) + { + delete[] p->second.contents; + p->second.contents = NULL; + } + } +} - if (isym.get_st_type() == elfcpp::STT_SECTION) - continue; +// Input_objects methods. + +// Add a regular relocatable object to the list. Return false if this +// object should be ignored. + +bool +Input_objects::add_object(Object* obj) +{ + // Print the filename if the -t/--trace option is selected. + if (parameters->options().trace()) + gold_info("%s", obj->name().c_str()); + + if (!obj->is_dynamic()) + this->relobj_list_.push_back(static_cast(obj)); + else + { + // See if this is a duplicate SONAME. + Dynobj* dynobj = static_cast(obj); + const char* soname = dynobj->soname(); - unsigned int st_shndx = isym.get_st_shndx(); - if (st_shndx < elfcpp::SHN_LORESERVE) + std::pair::iterator, bool> ins = + this->sonames_.insert(soname); + if (!ins.second) { - assert(st_shndx < mo.size()); - if (mo[st_shndx].output_section == NULL) - continue; - st_shndx = mo[st_shndx].output_section->out_shndx(); + // We have already seen a dynamic object with this soname. + return false; } - elfcpp::Sym_write osym(ov); + this->dynobj_list_.push_back(dynobj); + } + + // Add this object to the cross-referencer if requested. + if (parameters->options().user_set_print_symbol_counts() + || parameters->options().cref()) + { + if (this->cref_ == NULL) + this->cref_ = new Cref(); + this->cref_->add_object(obj); + } + + return true; +} - osym.put_st_name(sympool->get_offset(pnames + isym.get_st_name())); - osym.put_st_value(this->values_[i]); - 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); +// For each dynamic object, record whether we've seen all of its +// explicit dependencies. - ov += sym_size; +void +Input_objects::check_dynamic_dependencies() const +{ + bool issued_copy_dt_needed_error = false; + for (Dynobj_list::const_iterator p = this->dynobj_list_.begin(); + p != this->dynobj_list_.end(); + ++p) + { + const Dynobj::Needed& needed((*p)->needed()); + bool found_all = true; + Dynobj::Needed::const_iterator pneeded; + for (pneeded = needed.begin(); pneeded != needed.end(); ++pneeded) + { + if (this->sonames_.find(*pneeded) == this->sonames_.end()) + { + found_all = false; + break; + } + } + (*p)->set_has_unknown_needed_entries(!found_all); + + // --copy-dt-needed-entries aka --add-needed is a GNU ld option + // that gold does not support. However, they cause no trouble + // unless there is a DT_NEEDED entry that we don't know about; + // warn only in that case. + if (!found_all + && !issued_copy_dt_needed_error + && (parameters->options().copy_dt_needed_entries() + || parameters->options().add_needed())) + { + const char* optname; + if (parameters->options().copy_dt_needed_entries()) + optname = "--copy-dt-needed-entries"; + else + optname = "--add-needed"; + gold_error(_("%s is not supported but is required for %s in %s"), + optname, (*pneeded).c_str(), (*p)->name().c_str()); + issued_copy_dt_needed_error = true; + } } +} - assert(ov - oview == output_size); +// Start processing an archive. - of->write_output_view(this->local_symbol_offset_, output_size, oview); +void +Input_objects::archive_start(Archive* archive) +{ + if (parameters->options().user_set_print_symbol_counts() + || parameters->options().cref()) + { + if (this->cref_ == NULL) + this->cref_ = new Cref(); + this->cref_->add_archive_start(archive); + } } -// Input_objects methods. +// Stop processing an archive. + +void +Input_objects::archive_stop(Archive* archive) +{ + if (parameters->options().user_set_print_symbol_counts() + || parameters->options().cref()) + this->cref_->add_archive_stop(archive); +} -// Add a regular relocatable object to the list. +// Print symbol counts void -Input_objects::add_object(Object* obj) +Input_objects::print_symbol_counts(const Symbol_table* symtab) const { - if (obj->is_dynamic()) - this->dynobj_list_.push_back(static_cast(obj)); - else - this->relobj_list_.push_back(static_cast(obj)); + if (parameters->options().user_set_print_symbol_counts() + && this->cref_ != NULL) + this->cref_->print_symbol_counts(symtab); +} - Target* target = obj->target(); - if (this->target_ == NULL) - this->target_ = target; - else if (this->target_ != target) - { - fprintf(stderr, "%s: %s: incompatible target\n", - program_name, obj->name().c_str()); - gold_exit(false); - } +// Print a cross reference table. + +void +Input_objects::print_cref(const Symbol_table* symtab, FILE* f) const +{ + if (parameters->options().cref() && this->cref_ != NULL) + this->cref_->print_cref(symtab, f); } // Relocate_info methods. -// Return a string describing the location of a relocation. This is -// only used in error messages. +// Return a string describing the location of a relocation when file +// and lineno information is not available. This is only used in +// error messages. template std::string -Relocate_info::location(size_t relnum, off_t) const +Relocate_info::location(size_t, off_t offset) const { - std::string ret(this->object->name()); - ret += ": reloc "; + Sized_dwarf_line_info line_info(this->object); + std::string ret = line_info.addr2line(this->data_shndx, offset, NULL); + if (!ret.empty()) + return ret; + + ret = this->object->name(); + + Symbol_location_info info; + if (this->object->get_symbol_location_info(this->data_shndx, offset, &info)) + { + if (!info.source_file.empty()) + { + ret += ":"; + ret += info.source_file; + } + ret += ":"; + if (info.enclosing_symbol_type == elfcpp::STT_FUNC) + ret += _("function "); + ret += info.enclosing_symbol_name; + return ret; + } + + ret += "("; + ret += this->object->section_name(this->data_shndx); char buf[100]; - snprintf(buf, sizeof buf, "%zu", relnum); + snprintf(buf, sizeof buf, "+0x%lx)", static_cast(offset)); ret += buf; - ret += " in reloc section "; - snprintf(buf, sizeof buf, "%u", this->reloc_shndx); - ret += buf; - ret += " (" + this->object->section_name(this->reloc_shndx); - ret += ") for section "; - snprintf(buf, sizeof buf, "%u", this->data_shndx); - ret += buf; - ret += " (" + this->object->section_name(this->data_shndx) + ")"; return ret; } @@ -777,35 +3063,30 @@ using namespace gold; template Object* make_elf_sized_object(const std::string& name, Input_file* input_file, - off_t offset, const elfcpp::Ehdr& ehdr) + off_t offset, const elfcpp::Ehdr& ehdr, + bool* punconfigured) { - int et = ehdr.get_e_type(); - if (et != elfcpp::ET_REL && et != elfcpp::ET_DYN) - { - fprintf(stderr, "%s: %s: unsupported ELF type %d\n", - program_name, name.c_str(), static_cast(et)); - gold_exit(false); - } + Target* target = select_target(input_file, offset, + ehdr.get_e_machine(), size, big_endian, + ehdr.get_e_ident()[elfcpp::EI_OSABI], + ehdr.get_e_ident()[elfcpp::EI_ABIVERSION]); + if (target == NULL) + gold_fatal(_("%s: unsupported ELF machine number %d"), + name.c_str(), ehdr.get_e_machine()); - if (et == elfcpp::ET_REL) - { - Sized_relobj* obj = - new Sized_relobj(name, input_file, offset, ehdr); - obj->setup(ehdr); - return obj; - } - else + if (!parameters->target_valid()) + set_parameters_target(target); + else if (target != ¶meters->target()) { - // elfcpp::ET_DYN - fprintf(stderr, _("%s: %s: dynamic objects are not yet supported\n"), - program_name, name.c_str()); - gold_exit(false); -// Sized_dynobj* obj = -// new Sized_dynobj(this->input_.name(), input_file, -// offset, ehdr); -// obj->setup(ehdr); -// return obj; + if (punconfigured != NULL) + *punconfigured = true; + else + gold_error(_("%s: incompatible target"), name.c_str()); + return NULL; } + + return target->make_elf_object(name, input_file, offset, + ehdr); } } // End anonymous namespace. @@ -813,132 +3094,259 @@ make_elf_sized_object(const std::string& name, Input_file* input_file, namespace gold { -// Read an ELF file and return the appropriate instance of Object. +// Return whether INPUT_FILE is an ELF object. -Object* -make_elf_object(const std::string& name, Input_file* input_file, off_t offset, - const unsigned char* p, off_t bytes) +bool +is_elf_object(Input_file* input_file, off_t offset, + const unsigned char** start, int* read_size) { - if (bytes < elfcpp::EI_NIDENT) - { - fprintf(stderr, _("%s: %s: ELF file too short\n"), - program_name, name.c_str()); - gold_exit(false); - } + off_t filesize = input_file->file().filesize(); + int want = elfcpp::Elf_recognizer::max_header_size; + if (filesize - offset < want) + want = filesize - offset; - int v = p[elfcpp::EI_VERSION]; - if (v != elfcpp::EV_CURRENT) - { - if (v == elfcpp::EV_NONE) - fprintf(stderr, _("%s: %s: invalid ELF version 0\n"), - program_name, name.c_str()); - else - fprintf(stderr, _("%s: %s: unsupported ELF version %d\n"), - program_name, name.c_str(), v); - gold_exit(false); - } + const unsigned char* p = input_file->file().get_view(offset, 0, want, + true, false); + *start = p; + *read_size = want; - int c = p[elfcpp::EI_CLASS]; - if (c == elfcpp::ELFCLASSNONE) - { - fprintf(stderr, _("%s: %s: invalid ELF class 0\n"), - program_name, name.c_str()); - gold_exit(false); - } - else if (c != elfcpp::ELFCLASS32 - && c != elfcpp::ELFCLASS64) - { - fprintf(stderr, _("%s: %s: unsupported ELF class %d\n"), - program_name, name.c_str(), c); - gold_exit(false); - } + return elfcpp::Elf_recognizer::is_elf_file(p, want); +} - int d = p[elfcpp::EI_DATA]; - if (d == elfcpp::ELFDATANONE) - { - fprintf(stderr, _("%s: %s: invalid ELF data encoding\n"), - program_name, name.c_str()); - gold_exit(false); - } - else if (d != elfcpp::ELFDATA2LSB - && d != elfcpp::ELFDATA2MSB) +// Read an ELF file and return the appropriate instance of Object. + +Object* +make_elf_object(const std::string& name, Input_file* input_file, off_t offset, + const unsigned char* p, section_offset_type bytes, + bool* punconfigured) +{ + if (punconfigured != NULL) + *punconfigured = false; + + std::string error; + bool big_endian = false; + int size = 0; + if (!elfcpp::Elf_recognizer::is_valid_header(p, bytes, &size, + &big_endian, &error)) { - fprintf(stderr, _("%s: %s: unsupported ELF data encoding %d\n"), - program_name, name.c_str(), d); - gold_exit(false); + gold_error(_("%s: %s"), name.c_str(), error.c_str()); + return NULL; } - bool big_endian = d == elfcpp::ELFDATA2MSB; - - if (c == elfcpp::ELFCLASS32) + if (size == 32) { - if (bytes < elfcpp::Elf_sizes<32>::ehdr_size) - { - fprintf(stderr, _("%s: %s: ELF file too short\n"), - program_name, name.c_str()); - gold_exit(false); - } if (big_endian) { +#ifdef HAVE_TARGET_32_BIG elfcpp::Ehdr<32, true> ehdr(p); return make_elf_sized_object<32, true>(name, input_file, - offset, ehdr); + offset, ehdr, punconfigured); +#else + if (punconfigured != NULL) + *punconfigured = true; + else + gold_error(_("%s: not configured to support " + "32-bit big-endian object"), + name.c_str()); + return NULL; +#endif } else { +#ifdef HAVE_TARGET_32_LITTLE elfcpp::Ehdr<32, false> ehdr(p); return make_elf_sized_object<32, false>(name, input_file, - offset, ehdr); + offset, ehdr, punconfigured); +#else + if (punconfigured != NULL) + *punconfigured = true; + else + gold_error(_("%s: not configured to support " + "32-bit little-endian object"), + name.c_str()); + return NULL; +#endif } } - else + else if (size == 64) { - if (bytes < elfcpp::Elf_sizes<32>::ehdr_size) - { - fprintf(stderr, _("%s: %s: ELF file too short\n"), - program_name, name.c_str()); - gold_exit(false); - } if (big_endian) { +#ifdef HAVE_TARGET_64_BIG elfcpp::Ehdr<64, true> ehdr(p); return make_elf_sized_object<64, true>(name, input_file, - offset, ehdr); + offset, ehdr, punconfigured); +#else + if (punconfigured != NULL) + *punconfigured = true; + else + gold_error(_("%s: not configured to support " + "64-bit big-endian object"), + name.c_str()); + return NULL; +#endif } else { +#ifdef HAVE_TARGET_64_LITTLE elfcpp::Ehdr<64, false> ehdr(p); return make_elf_sized_object<64, false>(name, input_file, - offset, ehdr); + offset, ehdr, punconfigured); +#else + if (punconfigured != NULL) + *punconfigured = true; + else + gold_error(_("%s: not configured to support " + "64-bit little-endian object"), + name.c_str()); + return NULL; +#endif } } + else + gold_unreachable(); } -// Instantiate the templates we need. We could use the configure -// script to restrict this to only the ones for implemented targets. +// Instantiate the templates we need. + +#ifdef HAVE_TARGET_32_LITTLE +template +void +Object::read_section_data<32, false>(elfcpp::Elf_file<32, false, Object>*, + Read_symbols_data*); +template +const unsigned char* +Object::find_shdr<32,false>(const unsigned char*, const char*, const char*, + section_size_type, const unsigned char*) const; +#endif + +#ifdef HAVE_TARGET_32_BIG +template +void +Object::read_section_data<32, true>(elfcpp::Elf_file<32, true, Object>*, + Read_symbols_data*); +template +const unsigned char* +Object::find_shdr<32,true>(const unsigned char*, const char*, const char*, + section_size_type, const unsigned char*) const; +#endif + +#ifdef HAVE_TARGET_64_LITTLE +template +void +Object::read_section_data<64, false>(elfcpp::Elf_file<64, false, Object>*, + Read_symbols_data*); +template +const unsigned char* +Object::find_shdr<64,false>(const unsigned char*, const char*, const char*, + section_size_type, const unsigned char*) const; +#endif + +#ifdef HAVE_TARGET_64_BIG +template +void +Object::read_section_data<64, true>(elfcpp::Elf_file<64, true, Object>*, + Read_symbols_data*); +template +const unsigned char* +Object::find_shdr<64,true>(const unsigned char*, const char*, const char*, + section_size_type, const unsigned char*) const; +#endif +#ifdef HAVE_TARGET_32_LITTLE template class Sized_relobj<32, false>; template +class Sized_relobj_file<32, false>; +#endif + +#ifdef HAVE_TARGET_32_BIG +template class Sized_relobj<32, true>; template +class Sized_relobj_file<32, true>; +#endif + +#ifdef HAVE_TARGET_64_LITTLE +template class Sized_relobj<64, false>; template +class Sized_relobj_file<64, false>; +#endif + +#ifdef HAVE_TARGET_64_BIG +template class Sized_relobj<64, true>; template +class Sized_relobj_file<64, true>; +#endif + +#ifdef HAVE_TARGET_32_LITTLE +template struct Relocate_info<32, false>; +#endif +#ifdef HAVE_TARGET_32_BIG template struct Relocate_info<32, true>; +#endif +#ifdef HAVE_TARGET_64_LITTLE template struct Relocate_info<64, false>; +#endif +#ifdef HAVE_TARGET_64_BIG template struct Relocate_info<64, true>; +#endif + +#ifdef HAVE_TARGET_32_LITTLE +template +void +Xindex::initialize_symtab_xindex<32, false>(Object*, unsigned int); + +template +void +Xindex::read_symtab_xindex<32, false>(Object*, unsigned int, + const unsigned char*); +#endif + +#ifdef HAVE_TARGET_32_BIG +template +void +Xindex::initialize_symtab_xindex<32, true>(Object*, unsigned int); + +template +void +Xindex::read_symtab_xindex<32, true>(Object*, unsigned int, + const unsigned char*); +#endif + +#ifdef HAVE_TARGET_64_LITTLE +template +void +Xindex::initialize_symtab_xindex<64, false>(Object*, unsigned int); + +template +void +Xindex::read_symtab_xindex<64, false>(Object*, unsigned int, + const unsigned char*); +#endif + +#ifdef HAVE_TARGET_64_BIG +template +void +Xindex::initialize_symtab_xindex<64, true>(Object*, unsigned int); + +template +void +Xindex::read_symtab_xindex<64, true>(Object*, unsigned int, + const unsigned char*); +#endif } // End namespace gold.