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
25using namespace llvm;
26
27cl::opt<std::string> OldSymbolFile(cl::Positional, cl::Required,
28                                   cl::desc("<symbol-file>"));
29cl::opt<std::string> NewSymbolFile(cl::Positional, cl::Required,
30                                   cl::desc("<symbol-file>"));
31cl::opt<std::string> RemappingFile("remapping-file", cl::Required,
32                                   cl::desc("Remapping file"));
33cl::alias RemappingFileA("r", cl::aliasopt(RemappingFile));
34cl::opt<std::string> OutputFilename("output", cl::value_desc("output"),
35                                    cl::init("-"), cl::desc("Output file"));
36cl::alias OutputFilenameA("o", cl::aliasopt(OutputFilename));
37
38cl::opt<bool> WarnAmbiguous(
39    "Wambiguous",
40    cl::desc("Warn on equivalent symbols in the output symbol list"));
41cl::opt<bool> WarnIncomplete(
42    "Wincomplete",
43    cl::desc("Warn on input symbols missing from output symbol list"));
44
45static 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
56static 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
68static void exitWithError(Error E, StringRef Whence = "") {
69  exitWithError(toString(std::move(E)), Whence);
70}
71
72static void exitWithErrorCode(std::error_code EC, StringRef Whence = "") {
73  exitWithError(EC.message(), Whence);
74}
75
76static 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
130int 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::OF_Text);
149  if (EC)
150    exitWithErrorCode(EC, OutputFilename);
151
152  remapSymbols(*OldSymbolBufOrError.get(), *NewSymbolBufOrError.get(),
153               *RemappingBufOrError.get(), OS);
154}
155