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,
  54                           SrcMgr::CharacteristicKind FileType) override;
  55
  56   void EndOfMainFile() override {
  57     OutputGraphFile();
  58   }
  59
  60 };
  61 }
  62
  63 void clang::AttachDependencyGraphGen(Preprocessor &PP, StringRef OutputFile,
  64                                      StringRef SysRoot) {
  65   PP.addPPCallbacks(llvm::make_unique<DependencyGraphCallback>(&PP, OutputFile,
  66                                                                SysRoot));
  67 }
  68
  69 void DependencyGraphCallback::InclusionDirective(
  70     SourceLocation HashLoc,
  71     const Token &IncludeTok,
  72     StringRef FileName,
  73     bool IsAngled,
  74     CharSourceRange FilenameRange,
  75     const FileEntry *File,
  76     StringRef SearchPath,
  77     StringRef RelativePath,
  78     const Module *Imported,
  79     SrcMgr::CharacteristicKind FileType) {
  80   if (!File)
  81     return;
  82
  83   SourceManager &SM = PP->getSourceManager();
  84   const FileEntry *FromFile
  85     = SM.getFileEntryForID(SM.getFileID(SM.getExpansionLoc(HashLoc)));
  86   if (!FromFile)
  87     return;
  88
  89   Dependencies[FromFile].push_back(File);
  90
  91   AllFiles.insert(File);
  92   AllFiles.insert(FromFile);
  93 }
  94
  95 raw_ostream &
  96 DependencyGraphCallback::writeNodeReference(raw_ostream &OS,
  97                                             const FileEntry *Node) {
  98   OS << "header_" << Node->getUID();
  99   return OS;
 100 }
 101
 102 void DependencyGraphCallback::OutputGraphFile() {
 103   std::error_code EC;
 104   llvm::raw_fd_ostream OS(OutputFile, EC, llvm::sys::fs::F_Text);
 105   if (EC) {
 106     PP->getDiagnostics().Report(diag::err_fe_error_opening) << OutputFile
 107                                                             << EC.message();
 108     return;
 109   }
 110
 111   OS << "digraph \"dependencies\" {\n";
 112
 113   // Write the nodes
 114   for (unsigned I = 0, N = AllFiles.size(); I != N; ++I) {
 115     // Write the node itself.
 116     OS.indent(2);
 117     writeNodeReference(OS, AllFiles[I]);
 118     OS << " [ shape=\"box\", label=\"";
 119     StringRef FileName = AllFiles[I]->getName();
 120     if (FileName.startswith(SysRoot))
 121       FileName = FileName.substr(SysRoot.size());
 122
 123     OS << DOT::EscapeString(FileName)
 124     << "\"];\n";
 125   }
 126
 127   // Write the edges
 128   for (DependencyMap::iterator F = Dependencies.begin(),
 129                             FEnd = Dependencies.end();
 130        F != FEnd; ++F) {
 131     for (unsigned I = 0, N = F->second.size(); I != N; ++I) {
 132       OS.indent(2);
 133       writeNodeReference(OS, F->first);
 134       OS << " -> ";
 135       writeNodeReference(OS, F->second[I]);
 136       OS << ";\n";
 137     }
 138   }
 139   OS << "}\n";
 140 }
 141