1 //===-- llvm-c++filt.cpp --------------------------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #include "llvm/ADT/StringExtras.h" 10 #include "llvm/Demangle/Demangle.h" 11 #include "llvm/Demangle/StringViewExtras.h" 12 #include "llvm/Option/Arg.h" 13 #include "llvm/Option/ArgList.h" 14 #include "llvm/Option/Option.h" 15 #include "llvm/Support/CommandLine.h" 16 #include "llvm/Support/InitLLVM.h" 17 #include "llvm/Support/LLVMDriver.h" 18 #include "llvm/Support/WithColor.h" 19 #include "llvm/Support/raw_ostream.h" 20 #include "llvm/TargetParser/Host.h" 21 #include "llvm/TargetParser/Triple.h" 22 #include <cstdlib> 23 #include <iostream> 24 25 using namespace llvm; 26 27 namespace { 28 enum ID { 29 OPT_INVALID = 0, // This is not an option ID. 30 #define OPTION(...) LLVM_MAKE_OPT_ID(__VA_ARGS__), 31 #include "Opts.inc" 32 #undef OPTION 33 }; 34 35 #define PREFIX(NAME, VALUE) \ 36 static constexpr llvm::StringLiteral NAME##_init[] = VALUE; \ 37 static constexpr llvm::ArrayRef<llvm::StringLiteral> NAME( \ 38 NAME##_init, std::size(NAME##_init) - 1); 39 #include "Opts.inc" 40 #undef PREFIX 41 42 using namespace llvm::opt; 43 static constexpr opt::OptTable::Info InfoTable[] = { 44 #define OPTION(...) LLVM_CONSTRUCT_OPT_INFO(__VA_ARGS__), 45 #include "Opts.inc" 46 #undef OPTION 47 }; 48 49 class CxxfiltOptTable : public opt::GenericOptTable { 50 public: 51 CxxfiltOptTable() : opt::GenericOptTable(InfoTable) { 52 setGroupedShortOptions(true); 53 } 54 }; 55 } // namespace 56 57 static bool StripUnderscore; 58 static bool Types; 59 60 static StringRef ToolName; 61 62 static void error(const Twine &Message) { 63 WithColor::error(errs(), ToolName) << Message << '\n'; 64 exit(1); 65 } 66 67 static std::string demangle(const std::string &Mangled) { 68 using llvm::itanium_demangle::starts_with; 69 std::string_view DecoratedStr = Mangled; 70 bool CanHaveLeadingDot = true; 71 if (StripUnderscore && DecoratedStr[0] == '_') { 72 DecoratedStr.remove_prefix(1); 73 CanHaveLeadingDot = false; 74 } 75 76 std::string Result; 77 if (nonMicrosoftDemangle(DecoratedStr, Result, CanHaveLeadingDot)) 78 return Result; 79 80 std::string Prefix; 81 char *Undecorated = nullptr; 82 83 if (Types) 84 Undecorated = itaniumDemangle(DecoratedStr); 85 86 if (!Undecorated && starts_with(DecoratedStr, "__imp_")) { 87 Prefix = "import thunk for "; 88 Undecorated = itaniumDemangle(DecoratedStr.substr(6)); 89 } 90 91 Result = Undecorated ? Prefix + Undecorated : Mangled; 92 free(Undecorated); 93 return Result; 94 } 95 96 // Split 'Source' on any character that fails to pass 'IsLegalChar'. The 97 // returned vector consists of pairs where 'first' is the delimited word, and 98 // 'second' are the delimiters following that word. 99 static void SplitStringDelims( 100 StringRef Source, 101 SmallVectorImpl<std::pair<StringRef, StringRef>> &OutFragments, 102 function_ref<bool(char)> IsLegalChar) { 103 // The beginning of the input string. 104 const auto Head = Source.begin(); 105 106 // Obtain any leading delimiters. 107 auto Start = std::find_if(Head, Source.end(), IsLegalChar); 108 if (Start != Head) 109 OutFragments.push_back({"", Source.slice(0, Start - Head)}); 110 111 // Capture each word and the delimiters following that word. 112 while (Start != Source.end()) { 113 Start = std::find_if(Start, Source.end(), IsLegalChar); 114 auto End = std::find_if_not(Start, Source.end(), IsLegalChar); 115 auto DEnd = std::find_if(End, Source.end(), IsLegalChar); 116 OutFragments.push_back({Source.slice(Start - Head, End - Head), 117 Source.slice(End - Head, DEnd - Head)}); 118 Start = DEnd; 119 } 120 } 121 122 // This returns true if 'C' is a character that can show up in an 123 // Itanium-mangled string. 124 static bool IsLegalItaniumChar(char C) { 125 // Itanium CXX ABI [External Names]p5.1.1: 126 // '$' and '.' in mangled names are reserved for private implementations. 127 return isAlnum(C) || C == '.' || C == '$' || C == '_'; 128 } 129 130 // If 'Split' is true, then 'Mangled' is broken into individual words and each 131 // word is demangled. Otherwise, the entire string is treated as a single 132 // mangled item. The result is output to 'OS'. 133 static void demangleLine(llvm::raw_ostream &OS, StringRef Mangled, bool Split) { 134 std::string Result; 135 if (Split) { 136 SmallVector<std::pair<StringRef, StringRef>, 16> Words; 137 SplitStringDelims(Mangled, Words, IsLegalItaniumChar); 138 for (const auto &Word : Words) 139 Result += ::demangle(std::string(Word.first)) + Word.second.str(); 140 } else 141 Result = ::demangle(std::string(Mangled)); 142 OS << Result << '\n'; 143 OS.flush(); 144 } 145 146 int llvm_cxxfilt_main(int argc, char **argv, const llvm::ToolContext &) { 147 InitLLVM X(argc, argv); 148 BumpPtrAllocator A; 149 StringSaver Saver(A); 150 CxxfiltOptTable Tbl; 151 ToolName = argv[0]; 152 opt::InputArgList Args = Tbl.parseArgs(argc, argv, OPT_UNKNOWN, Saver, 153 [&](StringRef Msg) { error(Msg); }); 154 if (Args.hasArg(OPT_help)) { 155 Tbl.printHelp(outs(), 156 (Twine(ToolName) + " [options] <mangled>").str().c_str(), 157 "LLVM symbol undecoration tool"); 158 // TODO Replace this with OptTable API once it adds extrahelp support. 159 outs() << "\nPass @FILE as argument to read options from FILE.\n"; 160 return 0; 161 } 162 if (Args.hasArg(OPT_version)) { 163 outs() << ToolName << '\n'; 164 cl::PrintVersionMessage(); 165 return 0; 166 } 167 168 // The default value depends on the default triple. Mach-O has symbols 169 // prefixed with "_", so strip by default. 170 if (opt::Arg *A = 171 Args.getLastArg(OPT_strip_underscore, OPT_no_strip_underscore)) 172 StripUnderscore = A->getOption().matches(OPT_strip_underscore); 173 else 174 StripUnderscore = Triple(sys::getProcessTriple()).isOSBinFormatMachO(); 175 176 Types = Args.hasArg(OPT_types); 177 178 std::vector<std::string> Decorated = Args.getAllArgValues(OPT_INPUT); 179 if (Decorated.empty()) 180 for (std::string Mangled; std::getline(std::cin, Mangled);) 181 demangleLine(llvm::outs(), Mangled, true); 182 else 183 for (const auto &Symbol : Decorated) 184 demangleLine(llvm::outs(), Symbol, false); 185 186 return EXIT_SUCCESS; 187 } 188