contrib/llvm/tools/clang/lib/Frontend/DependencyGraph.cpp

   1 //===--- DependencyGraph.cpp - Generate dependency file -------------------===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // This code generates a header dependency graph in DOT format, for use
  11 // with, e.g., GraphViz.
  12 //
  13 //===----------------------------------------------------------------------===//
  14
  15 #include "clang/Frontend/Utils.h"
  16 #include "clang/Basic/FileManager.h"
  17 #include "clang/Basic/SourceManager.h"
  18 #include "clang/Frontend/FrontendDiagnostic.h"
  19 #include "clang/Lex/PPCallbacks.h"
  20 #include "clang/Lex/Preprocessor.h"
  21 #include "llvm/ADT/SetVector.h"
  22 #include "llvm/Support/GraphWriter.h"
  23 #include "llvm/Support/raw_ostream.h"
  24
  25 using namespace clang;
  26 namespace DOT = llvm::DOT;
  27
  28 namespace {
  29 class DependencyGraphCallback : public PPCallbacks {
  30   const Preprocessor *PP;
  31   std::string OutputFile;
  32   std::string SysRoot;
  33   llvm::SetVector<const FileEntry *> AllFiles;
  34   typedef llvm::DenseMap<const FileEntry *,
  35                          SmallVector<const FileEntry *, 2> > DependencyMap;
  36
  37   DependencyMap Dependencies;
  38
  39 private:
  40   raw_ostream &writeNodeReference(raw_ostream &OS,
  41                                   const FileEntry *Node);
  42   void OutputGraphFile();
  43
  44 public:
  45   DependencyGraphCallback(const Preprocessor *_PP, StringRef OutputFile,
  46                           StringRef SysRoot)
  47     : PP(_PP), OutputFile(OutputFile.str()), SysRoot(SysRoot.str()) { }
  48
  49   void InclusionDirective(SourceLocation HashLoc, const Token &IncludeTok,
  50                           StringRef FileName, bool IsAngled,
  51                           CharSourceRange FilenameRange, const FileEntry *File,
  52                           StringRef SearchPath, StringRef RelativePath,
  53                           const Module *Imported) override;
  54
  55   void EndOfMainFile() override {
  56     OutputGraphFile();
  57   }
  58
  59 };
  60 }
  61
  62 void clang::AttachDependencyGraphGen(Preprocessor &PP, StringRef OutputFile,
  63                                      StringRef SysRoot) {
  64   PP.addPPCallbacks(llvm::make_unique<DependencyGraphCallback>(&PP, OutputFile,
  65                                                                SysRoot));
  66 }
  67
  68 void DependencyGraphCallback::InclusionDirective(SourceLocation HashLoc,
  69                                                  const Token &IncludeTok,
  70                                                  StringRef FileName,
  71                                                  bool IsAngled,
  72                                                  CharSourceRange FilenameRange,
  73                                                  const FileEntry *File,
  74                                                  StringRef SearchPath,
  75                                                  StringRef RelativePath,
  76                                                  const Module *Imported) {
  77   if (!File)
  78     return;
  79
  80   SourceManager &SM = PP->getSourceManager();
  81   const FileEntry *FromFile
  82     = SM.getFileEntryForID(SM.getFileID(SM.getExpansionLoc(HashLoc)));
  83   if (!FromFile)
  84     return;
  85
  86   Dependencies[FromFile].push_back(File);
  87
  88   AllFiles.insert(File);
  89   AllFiles.insert(FromFile);
  90 }
  91
  92 raw_ostream &
  93 DependencyGraphCallback::writeNodeReference(raw_ostream &OS,
  94                                             const FileEntry *Node) {
  95   OS << "header_" << Node->getUID();
  96   return OS;
  97 }
  98
  99 void DependencyGraphCallback::OutputGraphFile() {
 100   std::error_code EC;
 101   llvm::raw_fd_ostream OS(OutputFile, EC, llvm::sys::fs::F_Text);
 102   if (EC) {
 103     PP->getDiagnostics().Report(diag::err_fe_error_opening) << OutputFile
 104                                                             << EC.message();
 105     return;
 106   }
 107
 108   OS << "digraph \"dependencies\" {\n";
 109
 110   // Write the nodes
 111   for (unsigned I = 0, N = AllFiles.size(); I != N; ++I) {
 112     // Write the node itself.
 113     OS.indent(2);
 114     writeNodeReference(OS, AllFiles[I]);
 115     OS << " [ shape=\"box\", label=\"";
 116     StringRef FileName = AllFiles[I]->getName();
 117     if (FileName.startswith(SysRoot))
 118       FileName = FileName.substr(SysRoot.size());
 119
 120     OS << DOT::EscapeString(FileName)
 121     << "\"];\n";
 122   }
 123
 124   // Write the edges
 125   for (DependencyMap::iterator F = Dependencies.begin(),
 126                             FEnd = Dependencies.end();
 127        F != FEnd; ++F) {
 128     for (unsigned I = 0, N = F->second.size(); I != N; ++I) {
 129       OS.indent(2);
 130       writeNodeReference(OS, F->first);
 131       OS << " -> ";
 132       writeNodeReference(OS, F->second[I]);
 133       OS << ";\n";
 134     }
 135   }
 136   OS << "}\n";
 137 }
 138