// inremental.cc -- incremental linking support for gold
-// Copyright 2009 Free Software Foundation, Inc.
+// Copyright 2009, 2010 Free Software Foundation, Inc.
// Written by Mikolaj Zalewski <mikolajz@google.com>.
// This file is part of gold.
// MA 02110-1301, USA.
#include "gold.h"
-#include "elfcpp.h"
-using elfcpp::Convert;
+#include <cstdarg>
+#include "libiberty.h"
+
+#include "elfcpp.h"
+#include "output.h"
+#include "symtab.h"
+#include "incremental.h"
+#include "archive.h"
+#include "output.h"
+#include "target-select.h"
+#include "target.h"
namespace gold {
// Version information. Will change frequently during the development, later
// we could think about backward (and forward?) compatibility.
-const int INCREMENTAL_LINK_VERSION = 1;
+const unsigned int INCREMENTAL_LINK_VERSION = 1;
-namespace internal {
+// This class manages the .gnu_incremental_inputs section, which holds
+// the header information, a directory of input files, and separate
+// entries for each input file.
-// Header of the .gnu_incremental_input section.
-struct Incremental_input_header_data
+template<int size, bool big_endian>
+class Output_section_incremental_inputs : public Output_section_data
{
- // Incremental linker version.
- elfcpp::Elf_Word version;
+ public:
+ Output_section_incremental_inputs(const Incremental_inputs* inputs,
+ const Symbol_table* symtab)
+ : Output_section_data(size / 8), inputs_(inputs), symtab_(symtab)
+ { }
+
+ protected:
+ // Set the final data size.
+ void
+ set_final_data_size();
+
+ // Write the data to the file.
+ void
+ do_write(Output_file*);
+
+ // Write to a map file.
+ void
+ do_print_to_mapfile(Mapfile* mapfile) const
+ { mapfile->print_output_data(this, _("** incremental_inputs")); }
+
+ private:
+ // Write the section header.
+ unsigned char*
+ write_header(unsigned char* pov, unsigned int input_file_count,
+ section_offset_type command_line_offset);
- // Numer of input files in the link.
- elfcpp::Elf_Word input_file_count;
+ // Write the input file entries.
+ unsigned char*
+ write_input_files(unsigned char* oview, unsigned char* pov,
+ Stringpool* strtab);
- // Offset of command line options in .gnu_incremental_strtab.
- elfcpp::Elf_Word command_line_offset;
+ // Write the supplemental information blocks.
+ unsigned char*
+ write_info_blocks(unsigned char* oview, unsigned char* pov,
+ Stringpool* strtab, unsigned int* global_syms,
+ unsigned int global_sym_count);
- // Padding.
- elfcpp::Elf_Word reserved;
+ // Write the contents of the .gnu_incremental_symtab section.
+ void
+ write_symtab(unsigned char* pov, unsigned int* global_syms,
+ unsigned int global_sym_count);
+
+ // Write the contents of the .gnu_incremental_got_plt section.
+ void
+ write_got_plt(unsigned char* pov, off_t view_size);
+
+ // Typedefs for writing the data to the output sections.
+ typedef elfcpp::Swap<size, big_endian> Swap;
+ typedef elfcpp::Swap<16, big_endian> Swap16;
+ typedef elfcpp::Swap<32, big_endian> Swap32;
+ typedef elfcpp::Swap<64, big_endian> Swap64;
+
+ // Sizes of various structures.
+ static const int sizeof_addr = size / 8;
+ static const int header_size = 16;
+ static const int input_entry_size = 24;
+
+ // The Incremental_inputs object.
+ const Incremental_inputs* inputs_;
+
+ // The symbol table.
+ const Symbol_table* symtab_;
};
-// Data stored in .gnu_incremental_input after the header for each of the
-// Incremental_input_header_data::input_file_count input entries.
-struct Incremental_input_entry_data
+// Inform the user why we don't do an incremental link. Not called in
+// the obvious case of missing output file. TODO: Is this helpful?
+
+void
+vexplain_no_incremental(const char* format, va_list args)
+{
+ char* buf = NULL;
+ if (vasprintf(&buf, format, args) < 0)
+ gold_nomem();
+ gold_info(_("the link might take longer: "
+ "cannot perform incremental link: %s"), buf);
+ free(buf);
+}
+
+void
+explain_no_incremental(const char* format, ...)
+{
+ va_list args;
+ va_start(args, format);
+ vexplain_no_incremental(format, args);
+ va_end(args);
+}
+
+// Report an error.
+
+void
+Incremental_binary::error(const char* format, ...) const
{
- // Offset of file name in .gnu_incremental_strtab section.
- elfcpp::Elf_Word filename_offset;
+ va_list args;
+ va_start(args, format);
+ // Current code only checks if the file can be used for incremental linking,
+ // so errors shouldn't fail the build, but only result in a fallback to a
+ // full build.
+ // TODO: when we implement incremental editing of the file, we may need a
+ // flag that will cause errors to be treated seriously.
+ vexplain_no_incremental(format, args);
+ va_end(args);
+}
- // Offset of data in .gnu_incremental_input.
- elfcpp::Elf_Word data_offset;
+// Find the .gnu_incremental_inputs section and related sections.
- // Timestamp (in seconds).
- elfcpp::Elf_Xword timestamp_sec;
+template<int size, bool big_endian>
+bool
+Sized_incremental_binary<size, big_endian>::do_find_incremental_inputs_sections(
+ unsigned int* p_inputs_shndx,
+ unsigned int* p_symtab_shndx,
+ unsigned int* p_relocs_shndx,
+ unsigned int* p_got_plt_shndx,
+ unsigned int* p_strtab_shndx)
+{
+ unsigned int inputs_shndx =
+ this->elf_file_.find_section_by_type(elfcpp::SHT_GNU_INCREMENTAL_INPUTS);
+ if (inputs_shndx == elfcpp::SHN_UNDEF) // Not found.
+ return false;
- // Nano-second part of timestamp (if supported).
- elfcpp::Elf_Word timestamp_usec;
+ unsigned int symtab_shndx =
+ this->elf_file_.find_section_by_type(elfcpp::SHT_GNU_INCREMENTAL_SYMTAB);
+ if (symtab_shndx == elfcpp::SHN_UNDEF) // Not found.
+ return false;
+ if (this->elf_file_.section_link(symtab_shndx) != inputs_shndx)
+ return false;
- // Type of the input entry.
- elfcpp::Elf_Half input_type;
+ unsigned int relocs_shndx =
+ this->elf_file_.find_section_by_type(elfcpp::SHT_GNU_INCREMENTAL_RELOCS);
+ if (relocs_shndx == elfcpp::SHN_UNDEF) // Not found.
+ return false;
+ if (this->elf_file_.section_link(relocs_shndx) != inputs_shndx)
+ return false;
- // Padding.
- elfcpp::Elf_Half reserved;
-};
+ unsigned int got_plt_shndx =
+ this->elf_file_.find_section_by_type(elfcpp::SHT_GNU_INCREMENTAL_GOT_PLT);
+ if (got_plt_shndx == elfcpp::SHN_UNDEF) // Not found.
+ return false;
+ if (this->elf_file_.section_link(got_plt_shndx) != inputs_shndx)
+ return false;
+
+ unsigned int strtab_shndx = this->elf_file_.section_link(inputs_shndx);
+ if (strtab_shndx == elfcpp::SHN_UNDEF
+ || strtab_shndx > this->elf_file_.shnum()
+ || this->elf_file_.section_type(strtab_shndx) != elfcpp::SHT_STRTAB)
+ return false;
+
+ if (p_inputs_shndx != NULL)
+ *p_inputs_shndx = inputs_shndx;
+ if (p_symtab_shndx != NULL)
+ *p_symtab_shndx = symtab_shndx;
+ if (p_relocs_shndx != NULL)
+ *p_relocs_shndx = relocs_shndx;
+ if (p_got_plt_shndx != NULL)
+ *p_got_plt_shndx = got_plt_shndx;
+ if (p_strtab_shndx != NULL)
+ *p_strtab_shndx = strtab_shndx;
+ return true;
+}
+
+// Determine whether an incremental link based on the existing output file
+// can be done.
+
+template<int size, bool big_endian>
+bool
+Sized_incremental_binary<size, big_endian>::do_check_inputs(
+ Incremental_inputs* incremental_inputs)
+{
+ unsigned int inputs_shndx;
+ unsigned int symtab_shndx;
+ unsigned int relocs_shndx;
+ unsigned int plt_got_shndx;
+ unsigned int strtab_shndx;
+
+ if (!do_find_incremental_inputs_sections(&inputs_shndx, &symtab_shndx,
+ &relocs_shndx, &plt_got_shndx,
+ &strtab_shndx))
+ {
+ explain_no_incremental(_("no incremental data from previous build"));
+ return false;
+ }
+
+ Location inputs_location(this->elf_file_.section_contents(inputs_shndx));
+ Location symtab_location(this->elf_file_.section_contents(symtab_shndx));
+ Location relocs_location(this->elf_file_.section_contents(relocs_shndx));
+ Location strtab_location(this->elf_file_.section_contents(strtab_shndx));
+
+ View inputs_view(view(inputs_location));
+ View symtab_view(view(symtab_location));
+ View relocs_view(view(relocs_location));
+ View strtab_view(view(strtab_location));
+
+ elfcpp::Elf_strtab strtab(strtab_view.data(), strtab_location.data_size);
+
+ Incremental_inputs_reader<size, big_endian>
+ incoming_inputs(inputs_view.data(), strtab);
+
+ if (incoming_inputs.version() != INCREMENTAL_LINK_VERSION)
+ {
+ explain_no_incremental(_("different version of incremental build data"));
+ return false;
+ }
+
+ if (incremental_inputs->command_line() != incoming_inputs.command_line())
+ {
+ explain_no_incremental(_("command line changed"));
+ return false;
+ }
+
+ // TODO: compare incremental_inputs->inputs() with entries in data_view.
+
+ return true;
+}
+
+namespace
+{
+
+// Create a Sized_incremental_binary object of the specified size and
+// endianness. Fails if the target architecture is not supported.
+
+template<int size, bool big_endian>
+Incremental_binary*
+make_sized_incremental_binary(Output_file* file,
+ const elfcpp::Ehdr<size, big_endian>& ehdr)
+{
+ Target* target = select_target(ehdr.get_e_machine(), size, big_endian,
+ ehdr.get_e_ident()[elfcpp::EI_OSABI],
+ ehdr.get_e_ident()[elfcpp::EI_ABIVERSION]);
+ if (target == NULL)
+ {
+ explain_no_incremental(_("unsupported ELF machine number %d"),
+ ehdr.get_e_machine());
+ return NULL;
+ }
+
+ if (!parameters->target_valid())
+ set_parameters_target(target);
+ else if (target != ¶meters->target())
+ gold_error(_("%s: incompatible target"), file->filename());
+
+ return new Sized_incremental_binary<size, big_endian>(file, ehdr, target);
+}
+
+} // End of anonymous namespace.
+
+// Create an Incremental_binary object for FILE. Returns NULL is this is not
+// possible, e.g. FILE is not an ELF file or has an unsupported target. FILE
+// should be opened.
+
+Incremental_binary*
+open_incremental_binary(Output_file* file)
+{
+ off_t filesize = file->filesize();
+ int want = elfcpp::Elf_recognizer::max_header_size;
+ if (filesize < want)
+ want = filesize;
+
+ const unsigned char* p = file->get_input_view(0, want);
+ if (!elfcpp::Elf_recognizer::is_elf_file(p, want))
+ {
+ explain_no_incremental(_("output is not an ELF file."));
+ return NULL;
+ }
+
+ int size = 0;
+ bool big_endian = false;
+ std::string error;
+ if (!elfcpp::Elf_recognizer::is_valid_header(p, want, &size, &big_endian,
+ &error))
+ {
+ explain_no_incremental(error.c_str());
+ return NULL;
+ }
+
+ Incremental_binary* result = NULL;
+ if (size == 32)
+ {
+ if (big_endian)
+ {
+#ifdef HAVE_TARGET_32_BIG
+ result = make_sized_incremental_binary<32, true>(
+ file, elfcpp::Ehdr<32, true>(p));
+#else
+ explain_no_incremental(_("unsupported file: 32-bit, big-endian"));
+#endif
+ }
+ else
+ {
+#ifdef HAVE_TARGET_32_LITTLE
+ result = make_sized_incremental_binary<32, false>(
+ file, elfcpp::Ehdr<32, false>(p));
+#else
+ explain_no_incremental(_("unsupported file: 32-bit, little-endian"));
+#endif
+ }
+ }
+ else if (size == 64)
+ {
+ if (big_endian)
+ {
+#ifdef HAVE_TARGET_64_BIG
+ result = make_sized_incremental_binary<64, true>(
+ file, elfcpp::Ehdr<64, true>(p));
+#else
+ explain_no_incremental(_("unsupported file: 64-bit, big-endian"));
+#endif
+ }
+ else
+ {
+#ifdef HAVE_TARGET_64_LITTLE
+ result = make_sized_incremental_binary<64, false>(
+ file, elfcpp::Ehdr<64, false>(p));
+#else
+ explain_no_incremental(_("unsupported file: 64-bit, little-endian"));
+#endif
+ }
+ }
+ else
+ gold_unreachable();
+
+ return result;
+}
+
+// Analyzes the output file to check if incremental linking is possible and
+// (to be done) what files need to be relinked.
+
+bool
+Incremental_checker::can_incrementally_link_output_file()
+{
+ Output_file output(this->output_name_);
+ if (!output.open_for_modification())
+ return false;
+ Incremental_binary* binary = open_incremental_binary(&output);
+ if (binary == NULL)
+ return false;
+ return binary->check_inputs(this->incremental_inputs_);
+}
+
+// Class Incremental_inputs.
+
+// Add the command line to the string table, setting
+// command_line_key_. In incremental builds, the command line is
+// stored in .gnu_incremental_inputs so that the next linker run can
+// check if the command line options didn't change.
+
+void
+Incremental_inputs::report_command_line(int argc, const char* const* argv)
+{
+ // Always store 'gold' as argv[0] to avoid a full relink if the user used a
+ // different path to the linker.
+ std::string args("gold");
+ // Copied from collect_argv in main.cc.
+ for (int i = 1; i < argc; ++i)
+ {
+ // Adding/removing these options should not result in a full relink.
+ if (strcmp(argv[i], "--incremental") == 0
+ || strcmp(argv[i], "--incremental-full") == 0
+ || strcmp(argv[i], "--incremental-update") == 0
+ || strcmp(argv[i], "--incremental-changed") == 0
+ || strcmp(argv[i], "--incremental-unchanged") == 0
+ || strcmp(argv[i], "--incremental-unknown") == 0)
+ continue;
+
+ args.append(" '");
+ // Now append argv[i], but with all single-quotes escaped
+ const char* argpos = argv[i];
+ while (1)
+ {
+ const int len = strcspn(argpos, "'");
+ args.append(argpos, len);
+ if (argpos[len] == '\0')
+ break;
+ args.append("'\"'\"'");
+ argpos += len + 1;
+ }
+ args.append("'");
+ }
+
+ this->command_line_ = args;
+ this->strtab_->add(this->command_line_.c_str(), false,
+ &this->command_line_key_);
+}
+
+// Record the input archive file ARCHIVE. This is called by the
+// Add_archive_symbols task before determining which archive members
+// to include. We create the Incremental_archive_entry here and
+// attach it to the Archive, but we do not add it to the list of
+// input objects until report_archive_end is called.
+
+void
+Incremental_inputs::report_archive_begin(Archive* arch)
+{
+ Stringpool::Key filename_key;
+ Timespec mtime = arch->file().get_mtime();
+
+ this->strtab_->add(arch->filename().c_str(), false, &filename_key);
+ Incremental_archive_entry* entry =
+ new Incremental_archive_entry(filename_key, arch, mtime);
+ arch->set_incremental_info(entry);
+}
+
+// Finish recording the input archive file ARCHIVE. This is called by the
+// Add_archive_symbols task after determining which archive members
+// to include.
+
+void
+Incremental_inputs::report_archive_end(Archive* arch)
+{
+ Incremental_archive_entry* entry = arch->incremental_info();
+
+ gold_assert(entry != NULL);
+
+ // Collect unused global symbols.
+ for (Archive::Unused_symbol_iterator p = arch->unused_symbols_begin();
+ p != arch->unused_symbols_end();
+ ++p)
+ {
+ Stringpool::Key symbol_key;
+ this->strtab_->add(*p, true, &symbol_key);
+ entry->add_unused_global_symbol(symbol_key);
+ }
+ this->inputs_.push_back(entry);
+}
+
+// Record the input object file OBJ. If ARCH is not NULL, attach
+// the object file to the archive. This is called by the
+// Add_symbols task after finding out the type of the file.
+
+void
+Incremental_inputs::report_object(Object* obj, Archive* arch)
+{
+ Stringpool::Key filename_key;
+ Timespec mtime = obj->input_file()->file().get_mtime();
+
+ this->strtab_->add(obj->name().c_str(), false, &filename_key);
+ Incremental_object_entry* obj_entry =
+ new Incremental_object_entry(filename_key, obj, mtime);
+ this->inputs_.push_back(obj_entry);
+
+ if (arch != NULL)
+ {
+ Incremental_archive_entry* arch_entry = arch->incremental_info();
+ gold_assert(arch_entry != NULL);
+ arch_entry->add_object(obj_entry);
+ }
+
+ this->current_object_ = obj;
+ this->current_object_entry_ = obj_entry;
+}
+
+// Record the input object file OBJ. If ARCH is not NULL, attach
+// the object file to the archive. This is called by the
+// Add_symbols task after finding out the type of the file.
+
+void
+Incremental_inputs::report_input_section(Object* obj, unsigned int shndx,
+ const char* name, off_t sh_size)
+{
+ Stringpool::Key key = 0;
+
+ if (name != NULL)
+ this->strtab_->add(name, true, &key);
+
+ gold_assert(obj == this->current_object_);
+ this->current_object_entry_->add_input_section(shndx, key, sh_size);
+}
+
+// Record that the input argument INPUT is a script SCRIPT. This is
+// called by read_script after parsing the script and reading the list
+// of inputs added by this script.
+
+void
+Incremental_inputs::report_script(const std::string& filename,
+ Script_info* script, Timespec mtime)
+{
+ Stringpool::Key filename_key;
+
+ this->strtab_->add(filename.c_str(), false, &filename_key);
+ Incremental_script_entry* entry =
+ new Incremental_script_entry(filename_key, script, mtime);
+ this->inputs_.push_back(entry);
+}
+
+// Finalize the incremental link information. Called from
+// Layout::finalize.
+
+void
+Incremental_inputs::finalize()
+{
+ // Finalize the string table.
+ this->strtab_->set_string_offsets();
+}
+
+// Create the .gnu_incremental_inputs, _symtab, and _relocs input sections.
+
+void
+Incremental_inputs::create_data_sections(Symbol_table* symtab)
+{
+ switch (parameters->size_and_endianness())
+ {
+#ifdef HAVE_TARGET_32_LITTLE
+ case Parameters::TARGET_32_LITTLE:
+ this->inputs_section_ =
+ new Output_section_incremental_inputs<32, false>(this, symtab);
+ break;
+#endif
+#ifdef HAVE_TARGET_32_BIG
+ case Parameters::TARGET_32_BIG:
+ this->inputs_section_ =
+ new Output_section_incremental_inputs<32, true>(this, symtab);
+ break;
+#endif
+#ifdef HAVE_TARGET_64_LITTLE
+ case Parameters::TARGET_64_LITTLE:
+ this->inputs_section_ =
+ new Output_section_incremental_inputs<64, false>(this, symtab);
+ break;
+#endif
+#ifdef HAVE_TARGET_64_BIG
+ case Parameters::TARGET_64_BIG:
+ this->inputs_section_ =
+ new Output_section_incremental_inputs<64, true>(this, symtab);
+ break;
+#endif
+ default:
+ gold_unreachable();
+ }
+ this->symtab_section_ = new Output_data_space(4, "** incremental_symtab");
+ this->relocs_section_ = new Output_data_space(4, "** incremental_relocs");
+ this->got_plt_section_ = new Output_data_space(4, "** incremental_got_plt");
+}
+
+// Return the sh_entsize value for the .gnu_incremental_relocs section.
+unsigned int
+Incremental_inputs::relocs_entsize() const
+{
+ return 8 + 2 * parameters->target().get_size() / 8;
+}
+
+// Class Output_section_incremental_inputs.
+
+// Finalize the offsets for each input section and supplemental info block,
+// and set the final data size of the incremental output sections.
+
+template<int size, bool big_endian>
+void
+Output_section_incremental_inputs<size, big_endian>::set_final_data_size()
+{
+ const Incremental_inputs* inputs = this->inputs_;
+ const unsigned int sizeof_addr = size / 8;
+ const unsigned int rel_size = 8 + 2 * sizeof_addr;
+
+ // Offset of each input entry.
+ unsigned int input_offset = this->header_size;
+
+ // Offset of each supplemental info block.
+ unsigned int info_offset = this->header_size;
+ info_offset += this->input_entry_size * inputs->input_file_count();
+
+ // Count each input file and its supplemental information block.
+ for (Incremental_inputs::Input_list::const_iterator p =
+ inputs->input_files().begin();
+ p != inputs->input_files().end();
+ ++p)
+ {
+ // Set the offset of the input file entry.
+ (*p)->set_offset(input_offset);
+ input_offset += this->input_entry_size;
+
+ // Set the offset of the supplemental info block.
+ switch ((*p)->type())
+ {
+ case INCREMENTAL_INPUT_SCRIPT:
+ // No supplemental info for a script.
+ (*p)->set_info_offset(0);
+ break;
+ case INCREMENTAL_INPUT_OBJECT:
+ case INCREMENTAL_INPUT_ARCHIVE_MEMBER:
+ {
+ Incremental_object_entry* entry = (*p)->object_entry();
+ gold_assert(entry != NULL);
+ (*p)->set_info_offset(info_offset);
+ // Input section count + global symbol count.
+ info_offset += 8;
+ // Each input section.
+ info_offset += (entry->get_input_section_count()
+ * (8 + 2 * sizeof_addr));
+ // Each global symbol.
+ const Object::Symbols* syms = entry->object()->get_global_symbols();
+ info_offset += syms->size() * 16;
+ }
+ break;
+ case INCREMENTAL_INPUT_SHARED_LIBRARY:
+ {
+ Incremental_object_entry* entry = (*p)->object_entry();
+ gold_assert(entry != NULL);
+ (*p)->set_info_offset(info_offset);
+ // Global symbol count.
+ info_offset += 4;
+ // Each global symbol.
+ const Object::Symbols* syms = entry->object()->get_global_symbols();
+ unsigned int nsyms = syms != NULL ? syms->size() : 0;
+ info_offset += nsyms * 4;
+ }
+ break;
+ case INCREMENTAL_INPUT_ARCHIVE:
+ {
+ Incremental_archive_entry* entry = (*p)->archive_entry();
+ gold_assert(entry != NULL);
+ (*p)->set_info_offset(info_offset);
+ // Member count + unused global symbol count.
+ info_offset += 8;
+ // Each member.
+ info_offset += (entry->get_member_count() * 4);
+ // Each global symbol.
+ info_offset += (entry->get_unused_global_symbol_count() * 4);
+ }
+ break;
+ default:
+ gold_unreachable();
+ }
+ }
+
+ this->set_data_size(info_offset);
+
+ // Set the size of the .gnu_incremental_symtab section.
+ inputs->symtab_section()->set_current_data_size(this->symtab_->output_count()
+ * sizeof(unsigned int));
+
+ // Set the size of the .gnu_incremental_relocs section.
+ inputs->relocs_section()->set_current_data_size(inputs->get_reloc_count()
+ * rel_size);
+
+ // Set the size of the .gnu_incremental_got_plt section.
+ Sized_target<size, big_endian>* target =
+ parameters->sized_target<size, big_endian>();
+ unsigned int got_count = target->got_entry_count();
+ unsigned int plt_count = target->plt_entry_count();
+ unsigned int got_plt_size = 8; // GOT entry count, PLT entry count.
+ got_plt_size = (got_plt_size + got_count + 3) & ~3; // GOT type array.
+ got_plt_size += got_count * 4 + plt_count * 4; // GOT array, PLT array.
+ inputs->got_plt_section()->set_current_data_size(got_plt_size);
+}
+
+// Write the contents of the .gnu_incremental_inputs and
+// .gnu_incremental_symtab sections.
+template<int size, bool big_endian>
+void
+Output_section_incremental_inputs<size, big_endian>::do_write(Output_file* of)
+{
+ const Incremental_inputs* inputs = this->inputs_;
+ Stringpool* strtab = inputs->get_stringpool();
+
+ // Get a view into the .gnu_incremental_inputs section.
+ const off_t off = this->offset();
+ const off_t oview_size = this->data_size();
+ unsigned char* const oview = of->get_output_view(off, oview_size);
+ unsigned char* pov = oview;
+
+ // Get a view into the .gnu_incremental_symtab section.
+ const off_t symtab_off = inputs->symtab_section()->offset();
+ const off_t symtab_size = inputs->symtab_section()->data_size();
+ unsigned char* const symtab_view = of->get_output_view(symtab_off,
+ symtab_size);
+
+ // Allocate an array of linked list heads for the .gnu_incremental_symtab
+ // section. Each element corresponds to a global symbol in the output
+ // symbol table, and points to the head of the linked list that threads
+ // through the object file input entries. The value of each element
+ // is the section-relative offset to a global symbol entry in a
+ // supplemental information block.
+ unsigned int global_sym_count = this->symtab_->output_count();
+ unsigned int* global_syms = new unsigned int[global_sym_count];
+ memset(global_syms, 0, global_sym_count * sizeof(unsigned int));
+
+ // Write the section header.
+ Stringpool::Key command_line_key = inputs->command_line_key();
+ pov = this->write_header(pov, inputs->input_file_count(),
+ strtab->get_offset_from_key(command_line_key));
+
+ // Write the list of input files.
+ pov = this->write_input_files(oview, pov, strtab);
+
+ // Write the supplemental information blocks for each input file.
+ pov = this->write_info_blocks(oview, pov, strtab, global_syms,
+ global_sym_count);
+
+ gold_assert(pov - oview == oview_size);
+
+ // Write the .gnu_incremental_symtab section.
+ gold_assert(global_sym_count * 4 == symtab_size);
+ this->write_symtab(symtab_view, global_syms, global_sym_count);
+
+ delete[] global_syms;
+
+ // Write the .gnu_incremental_got_plt section.
+ const off_t got_plt_off = inputs->got_plt_section()->offset();
+ const off_t got_plt_size = inputs->got_plt_section()->data_size();
+ unsigned char* const got_plt_view = of->get_output_view(got_plt_off,
+ got_plt_size);
+ this->write_got_plt(got_plt_view, got_plt_size);
+
+ of->write_output_view(off, oview_size, oview);
+ of->write_output_view(symtab_off, symtab_size, symtab_view);
+ of->write_output_view(got_plt_off, got_plt_size, got_plt_view);
}
-// Accessors.
+// Write the section header: version, input file count, offset of command line
+// in the string table, and 4 bytes of padding.
-// See internal::Incremental_input_header for fields descriptions.
template<int size, bool big_endian>
-class Incremental_input_header_write
+unsigned char*
+Output_section_incremental_inputs<size, big_endian>::write_header(
+ unsigned char* pov,
+ unsigned int input_file_count,
+ section_offset_type command_line_offset)
+{
+ Swap32::writeval(pov, INCREMENTAL_LINK_VERSION);
+ Swap32::writeval(pov + 4, input_file_count);
+ Swap32::writeval(pov + 8, command_line_offset);
+ Swap32::writeval(pov + 12, 0);
+ return pov + this->header_size;
+}
+
+// Write the input file entries.
+
+template<int size, bool big_endian>
+unsigned char*
+Output_section_incremental_inputs<size, big_endian>::write_input_files(
+ unsigned char* oview,
+ unsigned char* pov,
+ Stringpool* strtab)
+{
+ const Incremental_inputs* inputs = this->inputs_;
+
+ for (Incremental_inputs::Input_list::const_iterator p =
+ inputs->input_files().begin();
+ p != inputs->input_files().end();
+ ++p)
+ {
+ gold_assert(static_cast<unsigned int>(pov - oview) == (*p)->get_offset());
+ section_offset_type filename_offset =
+ strtab->get_offset_from_key((*p)->get_filename_key());
+ const Timespec& mtime = (*p)->get_mtime();
+ Swap32::writeval(pov, filename_offset);
+ Swap32::writeval(pov + 4, (*p)->get_info_offset());
+ Swap64::writeval(pov + 8, mtime.seconds);
+ Swap32::writeval(pov + 16, mtime.nanoseconds);
+ Swap16::writeval(pov + 20, (*p)->type());
+ Swap16::writeval(pov + 22, 0);
+ pov += this->input_entry_size;
+ }
+ return pov;
+}
+
+// Write the supplemental information blocks.
+
+template<int size, bool big_endian>
+unsigned char*
+Output_section_incremental_inputs<size, big_endian>::write_info_blocks(
+ unsigned char* oview,
+ unsigned char* pov,
+ Stringpool* strtab,
+ unsigned int* global_syms,
+ unsigned int global_sym_count)
+{
+ const Incremental_inputs* inputs = this->inputs_;
+ unsigned int first_global_index = this->symtab_->first_global_index();
+
+ for (Incremental_inputs::Input_list::const_iterator p =
+ inputs->input_files().begin();
+ p != inputs->input_files().end();
+ ++p)
+ {
+ switch ((*p)->type())
+ {
+ case INCREMENTAL_INPUT_SCRIPT:
+ // No supplemental info for a script.
+ break;
+
+ case INCREMENTAL_INPUT_OBJECT:
+ case INCREMENTAL_INPUT_ARCHIVE_MEMBER:
+ {
+ gold_assert(static_cast<unsigned int>(pov - oview)
+ == (*p)->get_info_offset());
+ Incremental_object_entry* entry = (*p)->object_entry();
+ gold_assert(entry != NULL);
+ const Object* obj = entry->object();
+ const Object::Symbols* syms = obj->get_global_symbols();
+ // Write the input section count and global symbol count.
+ unsigned int nsections = entry->get_input_section_count();
+ unsigned int nsyms = syms->size();
+ Swap32::writeval(pov, nsections);
+ Swap32::writeval(pov + 4, nsyms);
+ pov += 8;
+
+ // For each input section, write the name, output section index,
+ // offset within output section, and input section size.
+ for (unsigned int i = 0; i < nsections; i++)
+ {
+ Stringpool::Key key = entry->get_input_section_name_key(i);
+ off_t name_offset = 0;
+ if (key != 0)
+ name_offset = strtab->get_offset_from_key(key);
+ int out_shndx = 0;
+ off_t out_offset = 0;
+ off_t sh_size = 0;
+ Output_section* os = obj->output_section(i);
+ if (os != NULL)
+ {
+ out_shndx = os->out_shndx();
+ out_offset = obj->output_section_offset(i);
+ sh_size = entry->get_input_section_size(i);
+ }
+ Swap32::writeval(pov, name_offset);
+ Swap32::writeval(pov + 4, out_shndx);
+ Swap::writeval(pov + 8, out_offset);
+ Swap::writeval(pov + 8 + sizeof_addr, sh_size);
+ pov += 8 + 2 * sizeof_addr;
+ }
+
+ // For each global symbol, write its associated relocations,
+ // add it to the linked list of globals, then write the
+ // supplemental information: global symbol table index,
+ // linked list chain pointer, relocation count, and offset
+ // to the relocations.
+ for (unsigned int i = 0; i < nsyms; i++)
+ {
+ const Symbol* sym = (*syms)[i];
+ if (sym->is_forwarder())
+ sym = this->symtab_->resolve_forwards(sym);
+ unsigned int symtab_index = sym->symtab_index();
+ unsigned int chain = 0;
+ unsigned int first_reloc = 0;
+ unsigned int nrelocs = obj->get_incremental_reloc_count(i);
+ if (nrelocs > 0)
+ {
+ gold_assert(symtab_index != -1U
+ && (symtab_index - first_global_index
+ < global_sym_count));
+ first_reloc = obj->get_incremental_reloc_base(i);
+ chain = global_syms[symtab_index - first_global_index];
+ global_syms[symtab_index - first_global_index] =
+ pov - oview;
+ }
+ Swap32::writeval(pov, symtab_index);
+ Swap32::writeval(pov + 4, chain);
+ Swap32::writeval(pov + 8, nrelocs);
+ Swap32::writeval(pov + 12, first_reloc * 3 * sizeof_addr);
+ pov += 16;
+ }
+ }
+ break;
+
+ case INCREMENTAL_INPUT_SHARED_LIBRARY:
+ {
+ gold_assert(static_cast<unsigned int>(pov - oview)
+ == (*p)->get_info_offset());
+ Incremental_object_entry* entry = (*p)->object_entry();
+ gold_assert(entry != NULL);
+ const Object* obj = entry->object();
+ const Object::Symbols* syms = obj->get_global_symbols();
+
+ // Write the global symbol count.
+ unsigned int nsyms = syms != NULL ? syms->size() : 0;
+ Swap32::writeval(pov, nsyms);
+ pov += 4;
+
+ // For each global symbol, write the global symbol table index.
+ for (unsigned int i = 0; i < nsyms; i++)
+ {
+ const Symbol* sym = (*syms)[i];
+ Swap32::writeval(pov, sym->symtab_index());
+ pov += 4;
+ }
+ }
+ break;
+
+ case INCREMENTAL_INPUT_ARCHIVE:
+ {
+ gold_assert(static_cast<unsigned int>(pov - oview)
+ == (*p)->get_info_offset());
+ Incremental_archive_entry* entry = (*p)->archive_entry();
+ gold_assert(entry != NULL);
+
+ // Write the member count and unused global symbol count.
+ unsigned int nmembers = entry->get_member_count();
+ unsigned int nsyms = entry->get_unused_global_symbol_count();
+ Swap32::writeval(pov, nmembers);
+ Swap32::writeval(pov + 4, nsyms);
+ pov += 8;
+
+ // For each member, write the offset to its input file entry.
+ for (unsigned int i = 0; i < nmembers; ++i)
+ {
+ Incremental_object_entry* member = entry->get_member(i);
+ Swap32::writeval(pov, member->get_offset());
+ pov += 4;
+ }
+
+ // For each global symbol, write the name offset.
+ for (unsigned int i = 0; i < nsyms; ++i)
+ {
+ Stringpool::Key key = entry->get_unused_global_symbol(i);
+ Swap32::writeval(pov, strtab->get_offset_from_key(key));
+ pov += 4;
+ }
+ }
+ break;
+
+ default:
+ gold_unreachable();
+ }
+ }
+ return pov;
+}
+
+// Write the contents of the .gnu_incremental_symtab section.
+
+template<int size, bool big_endian>
+void
+Output_section_incremental_inputs<size, big_endian>::write_symtab(
+ unsigned char* pov,
+ unsigned int* global_syms,
+ unsigned int global_sym_count)
+{
+ for (unsigned int i = 0; i < global_sym_count; ++i)
+ {
+ Swap32::writeval(pov, global_syms[i]);
+ pov += 4;
+ }
+}
+
+// This struct holds the view information needed to write the
+// .gnu_incremental_got_plt section.
+
+struct Got_plt_view_info
+{
+ // Start of the GOT type array in the output view.
+ unsigned char* got_type_p;
+ // Start of the GOT descriptor array in the output view.
+ unsigned char* got_desc_p;
+ // Start of the PLT descriptor array in the output view.
+ unsigned char* plt_desc_p;
+ // Number of GOT entries.
+ unsigned int got_count;
+ // Number of PLT entries.
+ unsigned int plt_count;
+ // Offset of the first non-reserved PLT entry (this is a target-dependent value).
+ unsigned int first_plt_entry_offset;
+ // Size of a PLT entry (this is a target-dependent value).
+ unsigned int plt_entry_size;
+ // Value to write in the GOT descriptor array. For global symbols,
+ // this is the global symbol table index; for local symbols, it is
+ // the offset of the input file entry in the .gnu_incremental_inputs
+ // section.
+ unsigned int got_descriptor;
+};
+
+// Functor class for processing a GOT offset list for local symbols.
+// Writes the GOT type and symbol index into the GOT type and descriptor
+// arrays in the output section.
+
+template<int size, bool big_endian>
+class Local_got_offset_visitor
{
public:
- Incremental_input_header_write(unsigned char *p)
- : p_(reinterpret_cast<internal::Incremental_input_header_data>(p))
+ Local_got_offset_visitor(struct Got_plt_view_info& info)
+ : info_(info)
{ }
void
- put_version(elfcpp::Elf_Word v)
- { this->p_->version = Convert<32, big_endian>::convert_host(v); }
+ operator()(unsigned int got_type, unsigned int got_offset)
+ {
+ unsigned int got_index = got_offset / this->got_entry_size_;
+ gold_assert(got_index < this->info_.got_count);
+ // We can only handle GOT entry types in the range 0..0x7e
+ // because we use a byte array to store them, and we use the
+ // high bit to flag a local symbol.
+ gold_assert(got_type < 0x7f);
+ this->info_.got_type_p[got_index] = got_type | 0x80;
+ unsigned char* pov = this->info_.got_desc_p + got_index * 4;
+ elfcpp::Swap<32, big_endian>::writeval(pov, this->info_.got_descriptor);
+ }
- void
- input_file_count(elfcpp::Elf_Word v)
- { this->p_->input_file_count = Convert<32, big_endian>::convert_host(v); }
+ private:
+ static const unsigned int got_entry_size_ = size / 8;
+ struct Got_plt_view_info& info_;
+};
- void
- command_line_offset(elfcpp::Elf_Word v)
- { this->p_->command_line_offset = Convert<32, big_endian>::convert_host(v); }
+// Functor class for processing a GOT offset list. Writes the GOT type
+// and symbol index into the GOT type and descriptor arrays in the output
+// section.
+
+template<int size, bool big_endian>
+class Global_got_offset_visitor
+{
+ public:
+ Global_got_offset_visitor(struct Got_plt_view_info& info)
+ : info_(info)
+ { }
void
- reserved(elfcpp::Elf_Word v)
- { this->p_->reserved = Convert<32, big_endian>::convert_host(v); }
+ operator()(unsigned int got_type, unsigned int got_offset)
+ {
+ unsigned int got_index = got_offset / this->got_entry_size_;
+ gold_assert(got_index < this->info_.got_count);
+ // We can only handle GOT entry types in the range 0..0x7e
+ // because we use a byte array to store them, and we use the
+ // high bit to flag a local symbol.
+ gold_assert(got_type < 0x7f);
+ this->info_.got_type_p[got_index] = got_type;
+ unsigned char* pov = this->info_.got_desc_p + got_index * 4;
+ elfcpp::Swap<32, big_endian>::writeval(pov, this->info_.got_descriptor);
+ }
private:
- internal::Incremental_input_header_data* p_;
+ static const unsigned int got_entry_size_ = size / 8;
+ struct Got_plt_view_info& info_;
};
-// See internal::Incremental_input_entry for fields descriptions.
+// Functor class for processing the global symbol table. Processes the
+// GOT offset list for the symbol, and writes the symbol table index
+// into the PLT descriptor array in the output section.
+
template<int size, bool big_endian>
-class Incremental_input_entry_write
+class Global_symbol_visitor_got_plt
{
public:
- Incremental_input_entry_write(unsigned char *p)
- : p_(reinterpret_cast<internal::Incremental_input_entry_data>(p))
+ Global_symbol_visitor_got_plt(struct Got_plt_view_info& info)
+ : info_(info)
{ }
void
- put_filename_offset(elfcpp::Elf_Word v)
- { this->p_->filename_offset = Convert<32, big_endian>::convert_host(v); }
+ operator()(const Sized_symbol<size>* sym)
+ {
+ typedef Global_got_offset_visitor<size, big_endian> Got_visitor;
+ const Got_offset_list* got_offsets = sym->got_offset_list();
+ if (got_offsets != NULL)
+ {
+ info_.got_descriptor = sym->symtab_index();
+ got_offsets->for_all_got_offsets(Got_visitor(info_));
+ }
+ if (sym->has_plt_offset())
+ {
+ unsigned int plt_index =
+ ((sym->plt_offset() - this->info_.first_plt_entry_offset)
+ / this->info_.plt_entry_size);
+ gold_assert(plt_index < this->info_.plt_count);
+ unsigned char* pov = this->info_.plt_desc_p + plt_index * 4;
+ elfcpp::Swap<32, big_endian>::writeval(pov, sym->symtab_index());
+ }
+ }
- void
- put_data_offset(elfcpp::Elf_Word v)
- { this->p_->data_offset = Convert<32, big_endian>::convert_host(v); }
+ private:
+ struct Got_plt_view_info& info_;
+};
- void
- put_timestamp_sec(elfcpp::Elf_Word v)
- { this->p_->timestamp_sec = Convert<32, big_endian>::convert_host(v); }
+// Write the contents of the .gnu_incremental_got_plt section.
- void
- put_timestamp_usec(elfcpp::Elf_Word v)
- { this->p_->timestamp_usec = Convert<32, big_endian>::convert_host(v); }
+template<int size, bool big_endian>
+void
+Output_section_incremental_inputs<size, big_endian>::write_got_plt(
+ unsigned char* pov,
+ off_t view_size)
+{
+ Sized_target<size, big_endian>* target =
+ parameters->sized_target<size, big_endian>();
- void
- put_input_type(elfcpp::Elf_Word v)
- { this->p_->input_type = Convert<32, big_endian>::convert_host(v); }
+ // Set up the view information for the functors.
+ struct Got_plt_view_info view_info;
+ view_info.got_count = target->got_entry_count();
+ view_info.plt_count = target->plt_entry_count();
+ view_info.first_plt_entry_offset = target->first_plt_entry_offset();
+ view_info.plt_entry_size = target->plt_entry_size();
+ view_info.got_type_p = pov + 8;
+ view_info.got_desc_p = (view_info.got_type_p
+ + ((view_info.got_count + 3) & ~3));
+ view_info.plt_desc_p = view_info.got_desc_p + view_info.got_count * 4;
- void
- put_reserved(elfcpp::Elf_Word v)
- { this->p_->reserved = Convert<32, big_endian>::convert_host(v); }
+ gold_assert(pov + view_size ==
+ view_info.plt_desc_p + view_info.plt_count * 4);
- private:
- internal::Incremental_input_entry_data* p_;
-};
+ // Write the section header.
+ Swap32::writeval(pov, view_info.got_count);
+ Swap32::writeval(pov + 4, view_info.plt_count);
+
+ // Initialize the GOT type array to 0xff (reserved).
+ memset(view_info.got_type_p, 0xff, view_info.got_count);
+
+ // Write the incremental GOT descriptors for local symbols.
+ for (Incremental_inputs::Input_list::const_iterator p =
+ this->inputs_->input_files().begin();
+ p != this->inputs_->input_files().end();
+ ++p)
+ {
+ if ((*p)->type() != INCREMENTAL_INPUT_OBJECT
+ && (*p)->type() != INCREMENTAL_INPUT_ARCHIVE_MEMBER)
+ continue;
+ Incremental_object_entry* entry = (*p)->object_entry();
+ gold_assert(entry != NULL);
+ const Sized_relobj<size, big_endian>* obj =
+ static_cast<Sized_relobj<size, big_endian>*>(entry->object());
+ gold_assert(obj != NULL);
+ unsigned int nsyms = obj->local_symbol_count();
+ for (unsigned int i = 0; i < nsyms; i++)
+ {
+ const Got_offset_list* got_offsets = obj->local_got_offset_list(i);
+ if (got_offsets != NULL)
+ {
+ typedef Local_got_offset_visitor<size, big_endian> Got_visitor;
+ view_info.got_descriptor = (*p)->get_offset();
+ got_offsets->for_all_got_offsets(Got_visitor(view_info));
+ }
+ }
+ }
+
+ // Write the incremental GOT and PLT descriptors for global symbols.
+ typedef Global_symbol_visitor_got_plt<size, big_endian> Symbol_visitor;
+ symtab_->for_all_symbols<size, Symbol_visitor>(Symbol_visitor(view_info));
+}
+
+// Instantiate the templates we need.
+
+#ifdef HAVE_TARGET_32_LITTLE
+template
+class Sized_incremental_binary<32, false>;
+#endif
+
+#ifdef HAVE_TARGET_32_BIG
+template
+class Sized_incremental_binary<32, true>;
+#endif
+
+#ifdef HAVE_TARGET_64_LITTLE
+template
+class Sized_incremental_binary<64, false>;
+#endif
+
+#ifdef HAVE_TARGET_64_BIG
+template
+class Sized_incremental_binary<64, true>;
+#endif
} // End namespace gold.
projects / deliverable / binutils-gdb.git / blobdiff