tools/llvm-cxxmap/llvm-cxxmap.cpp

   1 //===- llvm-cxxmap.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 // llvm-cxxmap computes a correspondence between old symbol names and new
  10 // symbol names based on a symbol equivalence file.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "llvm/ADT/DenseSet.h"
  15 #include "llvm/ADT/DenseMap.h"
  16 #include "llvm/ADT/StringRef.h"
  17 #include "llvm/Support/CommandLine.h"
  18 #include "llvm/Support/InitLLVM.h"
  19 #include "llvm/Support/LineIterator.h"
  20 #include "llvm/Support/MemoryBuffer.h"
  21 #include "llvm/Support/SymbolRemappingReader.h"
  22 #include "llvm/Support/WithColor.h"
  23 #include "llvm/Support/raw_ostream.h"
  24
  25 using namespace llvm;
  26
  27 cl::opt<std::string> OldSymbolFile(cl::Positional, cl::Required,
  28                                    cl::desc("<symbol-file>"));
  29 cl::opt<std::string> NewSymbolFile(cl::Positional, cl::Required,
  30                                    cl::desc("<symbol-file>"));
  31 cl::opt<std::string> RemappingFile("remapping-file", cl::Required,
  32                                    cl::desc("Remapping file"));
  33 cl::alias RemappingFileA("r", cl::aliasopt(RemappingFile));
  34 cl::opt<std::string> OutputFilename("output", cl::value_desc("output"),
  35                                     cl::init("-"), cl::desc("Output file"));
  36 cl::alias OutputFilenameA("o", cl::aliasopt(OutputFilename));
  37
  38 cl::opt<bool> WarnAmbiguous(
  39     "Wambiguous",
  40     cl::desc("Warn on equivalent symbols in the output symbol list"));
  41 cl::opt<bool> WarnIncomplete(
  42     "Wincomplete",
  43     cl::desc("Warn on input symbols missing from output symbol list"));
  44
  45 static void warn(Twine Message, Twine Whence = "",
  46                  std::string Hint = "") {
  47   WithColor::warning();
  48   std::string WhenceStr = Whence.str();
  49   if (!WhenceStr.empty())
  50     errs() << WhenceStr << ": ";
  51   errs() << Message << "\n";
  52   if (!Hint.empty())
  53     WithColor::note() << Hint << "\n";
  54 }
  55
  56 static void exitWithError(Twine Message, Twine Whence = "",
  57                           std::string Hint = "") {
  58   WithColor::error();
  59   std::string WhenceStr = Whence.str();
  60   if (!WhenceStr.empty())
  61     errs() << WhenceStr << ": ";
  62   errs() << Message << "\n";
  63   if (!Hint.empty())
  64     WithColor::note() << Hint << "\n";
  65   ::exit(1);
  66 }
  67
  68 static void exitWithError(Error E, StringRef Whence = "") {
  69   exitWithError(toString(std::move(E)), Whence);
  70 }
  71
  72 static void exitWithErrorCode(std::error_code EC, StringRef Whence = "") {
  73   exitWithError(EC.message(), Whence);
  74 }
  75
  76 static void remapSymbols(MemoryBuffer &OldSymbolFile,
  77                          MemoryBuffer &NewSymbolFile,
  78                          MemoryBuffer &RemappingFile,
  79                          raw_ostream &Out) {
  80   // Load the remapping file and prepare to canonicalize symbols.
  81   SymbolRemappingReader Reader;
  82   if (Error E = Reader.read(RemappingFile))
  83     exitWithError(std::move(E));
  84
  85   // Canonicalize the new symbols.
  86   DenseMap<SymbolRemappingReader::Key, StringRef> MappedNames;
  87   DenseSet<StringRef> UnparseableSymbols;
  88   for (line_iterator LineIt(NewSymbolFile, /*SkipBlanks=*/true, '#');
  89        !LineIt.is_at_eof(); ++LineIt) {
  90     StringRef Symbol = *LineIt;
  91
  92     auto K = Reader.insert(Symbol);
  93     if (!K) {
  94       UnparseableSymbols.insert(Symbol);
  95       continue;
  96     }
  97
  98     auto ItAndIsNew = MappedNames.insert({K, Symbol});
  99     if (WarnAmbiguous && !ItAndIsNew.second &&
 100         ItAndIsNew.first->second != Symbol) {
 101       warn("symbol " + Symbol + " is equivalent to earlier symbol " +
 102                ItAndIsNew.first->second,
 103            NewSymbolFile.getBufferIdentifier() + ":" +
 104                Twine(LineIt.line_number()),
 105            "later symbol will not be the target of any remappings");
 106     }
 107   }
 108
 109   // Figure out which new symbol each old symbol is equivalent to.
 110   for (line_iterator LineIt(OldSymbolFile, /*SkipBlanks=*/true, '#');
 111        !LineIt.is_at_eof(); ++LineIt) {
 112     StringRef Symbol = *LineIt;
 113
 114     auto K = Reader.lookup(Symbol);
 115     StringRef NewSymbol = MappedNames.lookup(K);
 116
 117     if (NewSymbol.empty()) {
 118       if (WarnIncomplete && !UnparseableSymbols.count(Symbol)) {
 119         warn("no new symbol matches old symbol " + Symbol,
 120              OldSymbolFile.getBufferIdentifier() + ":" +
 121                  Twine(LineIt.line_number()));
 122       }
 123       continue;
 124     }
 125
 126     Out << Symbol << " " << NewSymbol << "\n";
 127   }
 128 }
 129
 130 int main(int argc, const char *argv[]) {
 131   InitLLVM X(argc, argv);
 132
 133   cl::ParseCommandLineOptions(argc, argv, "LLVM C++ mangled name remapper\n");
 134
 135   auto OldSymbolBufOrError = MemoryBuffer::getFileOrSTDIN(OldSymbolFile);
 136   if (!OldSymbolBufOrError)
 137     exitWithErrorCode(OldSymbolBufOrError.getError(), OldSymbolFile);
 138
 139   auto NewSymbolBufOrError = MemoryBuffer::getFileOrSTDIN(NewSymbolFile);
 140   if (!NewSymbolBufOrError)
 141     exitWithErrorCode(NewSymbolBufOrError.getError(), NewSymbolFile);
 142
 143   auto RemappingBufOrError = MemoryBuffer::getFileOrSTDIN(RemappingFile);
 144   if (!RemappingBufOrError)
 145     exitWithErrorCode(RemappingBufOrError.getError(), RemappingFile);
 146
 147   std::error_code EC;
 148   raw_fd_ostream OS(OutputFilename.data(), EC, sys::fs::F_Text);
 149   if (EC)
 150     exitWithErrorCode(EC, OutputFilename);
 151
 152   remapSymbols(*OldSymbolBufOrError.get(), *NewSymbolBufOrError.get(),
 153                *RemappingBufOrError.get(), OS);
 154 }