--- /dev/null
+// inremental.h -- incremental linking support for gold -*- C++ -*-
+
+// Copyright 2009 Free Software Foundation, Inc.
+// Written by Mikolaj Zalewski <mikolajz@google.com>.
+
+// This file is part of gold.
+
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation; either version 3 of the License, or
+// (at your option) any later version.
+
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
+// MA 02110-1301, USA.
+
+#ifndef GOLD_INCREMENTAL_H
+#define GOLD_INCREMENTAL_H
+
+#include <map>
+#include <vector>
+
+#include "elfcpp_file.h"
+#include "stringpool.h"
+#include "workqueue.h"
+#include "fileread.h"
+#include "output.h"
+
+namespace gold
+{
+
+class Archive;
+class Input_argument;
+class Incremental_inputs_checker;
+class Object;
+class Output_section_data;
+
+// Incremental input type as stored in .gnu_incremental_inputs.
+
+enum Incremental_input_type
+{
+ INCREMENTAL_INPUT_INVALID = 0,
+ INCREMENTAL_INPUT_OBJECT = 1,
+ INCREMENTAL_INPUT_ARCHIVE = 2,
+ INCREMENTAL_INPUT_SHARED_LIBRARY = 3,
+ INCREMENTAL_INPUT_SCRIPT = 4
+};
+
+// An object representing the ELF file we edit during an incremental build.
+// Similar to Object or Dynobj, but operates on Output_file and contains
+// method specific to file edition (TBD). This is the abstract parent class
+// implemented in Sized_incremental_binary<size, big_endian> for a specific
+// endianness and size.
+
+class Incremental_binary
+{
+ public:
+ Incremental_binary(Output_file* output, Target* target)
+ : output_(output), target_(target)
+ { }
+
+ virtual
+ ~Incremental_binary()
+ { }
+
+ // Functions and types for the elfcpp::Elf_file interface. This
+ // permit us to use Incremental_binary as the File template parameter for
+ // elfcpp::Elf_file.
+
+ // The View class is returned by view. It must support a single
+ // method, data(). This is trivial, because Output_file::get_output_view
+ // does what we need.
+ class View
+ {
+ public:
+ View(const unsigned char* p)
+ : p_(p)
+ { }
+
+ const unsigned char*
+ data() const
+ { return this->p_; }
+
+ private:
+ const unsigned char* p_;
+ };
+
+ // Return a View.
+ View
+ view(off_t file_offset, section_size_type data_size)
+ { return View(this->output_->get_input_view(file_offset, data_size)); }
+
+ // A location in the file.
+ struct Location
+ {
+ off_t file_offset;
+ off_t data_size;
+
+ Location(off_t fo, section_size_type ds)
+ : file_offset(fo), data_size(ds)
+ { }
+
+ Location()
+ : file_offset(0), data_size(0)
+ { }
+ };
+
+ // Get a View given a Location.
+ View view(Location loc)
+ { return View(this->view(loc.file_offset, loc.data_size)); }
+
+ // Report an error.
+ void
+ error(const char* format, ...) const ATTRIBUTE_PRINTF_2;
+
+ // Find the .gnu_incremental_inputs section. It selects the first section
+ // of type SHT_GNU_INCREMENTAL_INPUTS. Returns false if such a section
+ // is not found.
+ bool
+ find_incremental_inputs_section(Location* location,
+ unsigned int* strtab_shndx)
+ { return do_find_incremental_inputs_section(location, strtab_shndx); }
+
+ // Check the .gnu_incremental_inputs section to see whether an incremental
+ // build is possible.
+ // TODO: on success, should report what files needs to be rebuilt.
+ // INCREMENTAL_INPUTS is used to read the canonical form of the command line
+ // and read the input arguments. TODO: for items that don't need to be
+ // rebuilt, we should also copy the incremental input information.
+ virtual bool
+ check_inputs(Incremental_inputs* incremental_inputs)
+ { return do_check_inputs(incremental_inputs); }
+
+ protected:
+ // Find incremental inputs section.
+ virtual bool
+ do_find_incremental_inputs_section(Location* location,
+ unsigned int* strtab_shndx) = 0;
+
+ // Check the .gnu_incremental_inputs section to see whether an incremental
+ // build is possible.
+ virtual bool
+ do_check_inputs(Incremental_inputs* incremental_inputs) = 0;
+
+ private:
+ // Edited output file object.
+ Output_file* output_;
+ // Target of the output file.
+ Target* target_;
+};
+
+template<int size, bool big_endian>
+class Sized_incremental_binary : public Incremental_binary
+{
+ public:
+ Sized_incremental_binary(Output_file* output,
+ const elfcpp::Ehdr<size, big_endian>& ehdr,
+ Target* target)
+ : Incremental_binary(output, target), elf_file_(this, ehdr)
+ { }
+
+ protected:
+ virtual bool
+ do_find_incremental_inputs_section(Location* location,
+ unsigned int* strtab_shndx);
+
+ virtual bool
+ do_check_inputs(Incremental_inputs* incremental_inputs);
+
+ private:
+ // Output as an ELF file.
+ elfcpp::Elf_file<size, big_endian, Incremental_binary> elf_file_;
+};
+
+// 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.
+Incremental_binary*
+open_incremental_binary(Output_file* file);
+
+// Code invoked early during an incremental link that checks what files need
+// to be relinked.
+class Incremental_checker
+{
+ public:
+ // Check if the file named OUTPUT_NAME can be linked incrementally.
+ // INCREMENTAL_INPUTS must have the canonical form of the command line
+ // and input arguments filled - at this point of linking other fields are
+ // probably not filled yet. TODO: for inputs that don't need to be
+ // rebuilt, this function should fill the incremental input information.
+ Incremental_checker(const char* output_name,
+ Incremental_inputs* incremental_inputs)
+ : output_name_(output_name), incremental_inputs_(incremental_inputs)
+ { }
+
+ // Analyzes the output file to check if incremental linking is possible and
+ // what files needs to be relinked.
+ bool
+ can_incrementally_link_output_file();
+
+ private:
+ // Name of the output file to analyze.
+ const char* output_name_;
+
+ // The Incremental_inputs object. At this stage of link, only the command
+ // line and inputs are filled.
+ Incremental_inputs* incremental_inputs_;
+};
+
+// This class contains the information needed during an incremental
+// build about the inputs necessary to build the .gnu_incremental_inputs.
+class Incremental_inputs
+{
+ public:
+ Incremental_inputs()
+ : lock_(new Lock()), inputs_(NULL), command_line_key_(0),
+ strtab_(new Stringpool())
+ { }
+ ~Incremental_inputs() { delete this->strtab_; }
+
+ // Record the command line.
+ void
+ report_command_line(int argc, const char* const* argv);
+
+ // Record the input arguments obtained from parsing the command line.
+ void
+ report_inputs(const Input_arguments& inputs)
+ { this->inputs_ = &inputs; }
+
+ // Record that the input argument INPUT is an archive ARCHIVE.
+ void
+ report_archive(const Input_argument* input, Archive* archive);
+
+ // Record that the input argument INPUT is to an object OBJ.
+ void
+ report_object(const Input_argument* input, Object* obj);
+
+ // Record that the input argument INPUT is to an script SCRIPT.
+ void
+ report_script(const Input_argument* input, Timespec mtime,
+ Script_info* script);
+
+ // Prepare for layout. Called from Layout::finalize.
+ void
+ finalize();
+
+ // Create the content of the .gnu_incremental_inputs section.
+ Output_section_data*
+ create_incremental_inputs_section_data();
+
+ // Return the .gnu_incremental_strtab stringpool.
+ Stringpool*
+ get_stringpool()
+ { return this->strtab_; }
+
+ // Return the canonical form of the command line, as will be stored in
+ // .gnu_incremental_strtab.
+ const std::string&
+ command_line()
+ { return this->command_line_; }
+
+ // Return the input files found in the command line.
+ const Input_arguments*
+ inputs()
+ { return this->inputs_; }
+
+ private:
+ // Code for each of the four possible variants of create_inputs_section_data.
+ template<int size, bool big_endian>
+ Output_section_data*
+ sized_create_inputs_section_data();
+
+ // Compute indexes in the order in which the inputs should appear in
+ // .gnu_incremental_inputs and put file names to the stringtable.
+ // This needs to be done after all the scripts are parsed.
+
+ void
+ finalize_inputs(Input_argument_list::const_iterator begin,
+ Input_argument_list::const_iterator end,
+ unsigned int* index);
+
+ // Additional data about an input needed for an incremental link.
+ // None of these pointers is owned by the structure.
+ struct Input_info
+ {
+ Input_info()
+ : type(INCREMENTAL_INPUT_INVALID), archive(NULL), filename_key(0),
+ index(0)
+ { }
+
+ // Type of the file pointed by this argument.
+ Incremental_input_type type;
+
+ union
+ {
+ // Present if type == INCREMENTAL_INPUT_ARCHIVE.
+ Archive* archive;
+
+ // Present if type == INCREMENTAL_INPUT_OBJECT or
+ // INCREMENTAL_INPUT_SHARED_LIBRARY.
+ Object* object;
+
+ // Present if type == INCREMENTAL_INPUT_SCRIPT.
+ Script_info* script;
+ };
+
+ // Key of the filename string in the section stringtable.
+ Stringpool::Key filename_key;
+
+ // Position of the entry information in the output section.
+ unsigned int index;
+
+ // Last modification time of the file.
+ Timespec mtime;
+ };
+
+ typedef std::map<const Input_argument*, Input_info> Inputs_info_map;
+
+ // A lock guarding access to inputs_ during the first phase of linking, when
+ // report_ function may be called from multiple threads.
+ Lock* lock_;
+
+ // The list of input arguments obtained from parsing the command line.
+ const Input_arguments* inputs_;
+
+ // A map containing additional information about the input elements.
+ Inputs_info_map inputs_map_;
+
+ // Canonical form of the command line, as will be stored in
+ // .gnu_incremental_strtab.
+ std::string command_line_;
+
+ // The key of the command line string in the string pool.
+ Stringpool::Key command_line_key_;
+
+ // The .gnu_incremental_strtab string pool associated with the
+ // .gnu_incremental_inputs.
+ Stringpool* strtab_;
+};
+
+} // End namespace gold.
+
+#endif // !defined(GOLD_INCREMENTAL_H)
projects / msp430-binutils.git / blobdiff