gold/incremental.h

   1 // inremental.h -- incremental linking support for gold   -*- C++ -*-
   2
   3 // Copyright 2009 Free Software Foundation, Inc.
   4 // Written by Mikolaj Zalewski <mikolajz@google.com>.
   5
   6 // This file is part of gold.
   7
   8 // This program is free software; you can redistribute it and/or modify
   9 // it under the terms of the GNU General Public License as published by
  10 // the Free Software Foundation; either version 3 of the License, or
  11 // (at your option) any later version.
  12
  13 // This program is distributed in the hope that it will be useful,
  14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 // GNU General Public License for more details.
  17
  18 // You should have received a copy of the GNU General Public License
  19 // along with this program; if not, write to the Free Software
  20 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  21 // MA 02110-1301, USA.
  22
  23 #ifndef GOLD_INCREMENTAL_H
  24 #define GOLD_INCREMENTAL_H
  25
  26 #include <map>
  27 #include <vector>
  28
  29 #include "stringpool.h"
  30 #include "workqueue.h"
  31
  32 namespace gold
  33 {
  34
  35 class Archive;
  36 class Input_argument;
  37 class Incremental_inputs_checker;
  38 class Object;
  39 class Output_section_data;
  40
  41 // Incremental input type as stored in .gnu_incremental_inputs.
  42
  43 enum Incremental_input_type
  44 {
  45   INCREMENTAL_INPUT_INVALID = 0,
  46   INCREMENTAL_INPUT_OBJECT = 1,
  47   INCREMENTAL_INPUT_ARCHIVE = 2,
  48   INCREMENTAL_INPUT_SHARED_LIBRARY = 3,
  49   INCREMENTAL_INPUT_SCRIPT = 4
  50 };
  51
  52 // This class contains the information needed during an incremental
  53 // build about the inputs necessary to build the .gnu_incremental_inputs.
  54 class Incremental_inputs
  55 {
  56  public:
  57   Incremental_inputs()
  58     : lock_(new Lock()), inputs_(NULL), command_line_key_(0),
  59       strtab_(new Stringpool())
  60   { }
  61   ~Incremental_inputs() { delete this->strtab_; }
  62
  63   // Record the command line.
  64   void
  65   report_command_line(int argc, const char* const* argv);
  66
  67   // Record the input arguments obtained from parsing the command line.
  68   void
  69   report_inputs(const Input_arguments& inputs)
  70   { this->inputs_ = &inputs; }
  71
  72   // Record that the input argument INPUT is an archive ARCHIVE.
  73   void
  74   report_archive(const Input_argument* input, Archive* archive);
  75
  76   // Record that the input argument INPUT is to an object OBJ.
  77   void
  78   report_object(const Input_argument* input, Object* obj);
  79
  80   // Record that the input argument INPUT is to an script SCRIPT.
  81   void
  82   report_script(const Input_argument* input, Script_info* script);
  83
  84   // Prepare for layout.  Called from Layout::finalize.
  85   void
  86   finalize();
  87
  88   // Create the content of the .gnu_incremental_inputs section.
  89   Output_section_data*
  90   create_incremental_inputs_section_data();
  91
  92   // Return the .gnu_incremental_strtab stringpool.
  93   Stringpool*
  94   get_stringpool()
  95   { return this->strtab_; }
  96
  97  private:
  98   // Code for each of the four possible variants of create_inputs_section_data.
  99   template<int size, bool big_endian>
 100   Output_section_data*
 101   sized_create_inputs_section_data();
 102
 103   // Compute indexes in the order in which the inputs should appear in
 104   // .gnu_incremental_inputs and put file names to the stringtable.
 105   // This needs to be done after all the scripts are parsed.
 106
 107   void
 108   finalize_inputs(Input_argument_list::const_iterator begin,
 109                   Input_argument_list::const_iterator end,
 110                   unsigned int* index);
 111
 112   // Additional data about an input needed for an incremental link.
 113   // None of these pointers is owned by the structure.
 114   struct Input_info
 115   {
 116     Input_info()
 117       : type(INCREMENTAL_INPUT_INVALID), archive(NULL), object(NULL),
 118         script(NULL), filename_key(0), index(0)
 119     { }
 120
 121     // Type of the file pointed by this argument.
 122     Incremental_input_type type;
 123
 124     // Present if type == INCREMENTAL_INPUT_ARCHIVE.
 125     Archive* archive;
 126
 127     // Present if type == INCREMENTAL_INPUT_OBJECT or
 128     // INCREMENTAL_INPUT_SHARED_LIBRARY.
 129     Object* object;
 130
 131     // Present if type == INCREMENTAL_INPUT_SCRIPT.
 132     Script_info* script;
 133
 134     // Key of the filename string in the section stringtable.
 135     Stringpool::Key filename_key;
 136
 137     // Position of the entry information in the output section.
 138     unsigned int index;
 139   };
 140
 141   typedef std::map<const Input_argument*, Input_info> Inputs_info_map;
 142
 143   // A lock guarding access to inputs_ during the first phase of linking, when
 144   // report_ function may be called from multiple threads.
 145   Lock* lock_;
 146
 147   // The list of input arguments obtained from parsing the command line.
 148   const Input_arguments* inputs_;
 149
 150   // A map containing additional information about the input elements.
 151   Inputs_info_map inputs_map_;
 152
 153   // The key of the command line string in the string pool.
 154   Stringpool::Key command_line_key_;
 155   // The .gnu_incremental_strtab string pool associated with the
 156   // .gnu_incremental_inputs.
 157   Stringpool* strtab_;
 158 };
 159
 160 } // End namespace gold.
 161
 162 #endif // !defined(GOLD_INCREMENTAL_H)