1 // reduced_debug_output.h -- reduce debugging information -*- C++ -*- 2 3 // Copyright (C) 2008-2016 Free Software Foundation, Inc. 4 // Written by Caleb Howe <cshowe (at) 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 // Reduce the size of the debug sections by emitting only debug line number 24 // information. We still need to emit skeleton debug_info and debug_abbrev 25 // sections for standard tools to parse the debug information correctly. These 26 // classes remove all debug information entries from the .debug_info section 27 // except for those describing compilation units as these DIEs contain 28 // references to the debug line information needed by most parsers. 29 30 #ifndef GOLD_REDUCED_DEBUG_OUTPUT_H 31 #define GOLD_REDUCED_DEBUG_OUTPUT_H 32 33 #include <map> 34 #include <utility> 35 #include <vector> 36 37 #include "output.h" 38 39 namespace gold 40 { 41 42 class Output_reduced_debug_abbrev_section : public Output_section 43 { 44 public: 45 Output_reduced_debug_abbrev_section(const char* name, elfcpp::Elf_Word flags, 46 elfcpp::Elf_Xword type) 47 : Output_section(name, flags, type), sized_(false), 48 abbrev_count_(0), failed_(false) 49 { this->set_requires_postprocessing(); } 50 51 unsigned char* get_new_abbrev(uint64_t* abbrev_number, 52 uint64_t abbrev_offset); 53 54 protected: 55 // Set the final data size. 56 void 57 set_final_data_size(); 58 59 // Write out the new debug abbreviations 60 void 61 do_write(Output_file*); 62 63 private: 64 void 65 failed(std::string reason) 66 { 67 gold_warning("%s", reason.c_str()); 68 failed_ = true; 69 } 70 71 // The reduced debug abbreviations 72 std::vector<unsigned char> data_; 73 74 // We map the abbreviation table offset and abbreviation number of the 75 // old abbreviation to the number and size of the new abbreviation. 76 std::map<std::pair<uint64_t, uint64_t>, 77 std::pair<uint64_t, uint64_t> > abbrev_mapping_; 78 79 bool sized_; 80 81 // The count of abbreviations in the output data 82 int abbrev_count_; 83 84 // Whether or not the debug reduction has failed for any reason 85 bool failed_; 86 }; 87 88 class Output_reduced_debug_info_section : public Output_section 89 { 90 public: 91 Output_reduced_debug_info_section(const char* name, elfcpp::Elf_Word flags, 92 elfcpp::Elf_Xword type) 93 : Output_section(name, flags, type), failed_(false) 94 { this->set_requires_postprocessing(); } 95 96 void 97 set_abbreviations(Output_reduced_debug_abbrev_section* abbrevs) 98 { associated_abbrev_ = abbrevs; } 99 100 protected: 101 // Set the final data size. 102 void 103 set_final_data_size(); 104 105 // Write out the new debug info 106 void 107 do_write(Output_file*); 108 109 private: 110 void 111 failed(std::string reason) 112 { 113 gold_warning("%s", reason.c_str()); 114 this->failed_ = true; 115 } 116 117 // Given a pointer to the beginning of a die and the beginning of the 118 // associated abbreviation fills in die_end with the end of the information 119 // entry. If successful returns true. Get_die_end also takes a pointer to 120 // the end of the buffer containing the die. If die_end would be beyond the 121 // end of the buffer, or if an unsupported dwarf form is encountered returns 122 // false. 123 bool 124 get_die_end(unsigned char* die, unsigned char* abbrev, 125 unsigned char** die_end, unsigned char* buffer_end, 126 int address_size, bool is64); 127 128 // The reduced debug info 129 std::vector<unsigned char> data_; 130 131 // Each debug info section needs to be associated with a debug abbrev section 132 Output_reduced_debug_abbrev_section* associated_abbrev_; 133 134 // Whether or not the debug reduction has failed for any reason 135 bool failed_; 136 }; 137 138 } // End namespace gold. 139 140 #endif // !defined(GOLD_REDUCED_DEBUG_OUTPUT_H) 141
