1 //===--- DependencyGraph.cpp - Generate dependency file -------------------===//
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
7 //===----------------------------------------------------------------------===//
9 // This code generates a header dependency graph in DOT format, for use
10 // with, e.g., GraphViz.
12 //===----------------------------------------------------------------------===//
14 #include "clang/Frontend/Utils.h"
15 #include "clang/Basic/FileManager.h"
16 #include "clang/Basic/SourceManager.h"
17 #include "clang/Frontend/FrontendDiagnostic.h"
18 #include "clang/Lex/PPCallbacks.h"
19 #include "clang/Lex/Preprocessor.h"
20 #include "llvm/ADT/SetVector.h"
21 #include "llvm/Support/GraphWriter.h"
22 #include "llvm/Support/raw_ostream.h"
24 using namespace clang;
25 namespace DOT = llvm::DOT;
28 class DependencyGraphCallback : public PPCallbacks {
29 const Preprocessor *PP;
30 std::string OutputFile;
32 llvm::SetVector<const FileEntry *> AllFiles;
33 typedef llvm::DenseMap<const FileEntry *,
34 SmallVector<const FileEntry *, 2> > DependencyMap;
36 DependencyMap Dependencies;
39 raw_ostream &writeNodeReference(raw_ostream &OS,
40 const FileEntry *Node);
41 void OutputGraphFile();
44 DependencyGraphCallback(const Preprocessor *_PP, StringRef OutputFile,
46 : PP(_PP), OutputFile(OutputFile.str()), SysRoot(SysRoot.str()) { }
48 void InclusionDirective(SourceLocation HashLoc, const Token &IncludeTok,
49 StringRef FileName, bool IsAngled,
50 CharSourceRange FilenameRange, const FileEntry *File,
51 StringRef SearchPath, StringRef RelativePath,
52 const Module *Imported,
53 SrcMgr::CharacteristicKind FileType) override;
55 void EndOfMainFile() override {
62 void clang::AttachDependencyGraphGen(Preprocessor &PP, StringRef OutputFile,
64 PP.addPPCallbacks(std::make_unique<DependencyGraphCallback>(&PP, OutputFile,
68 void DependencyGraphCallback::InclusionDirective(
69 SourceLocation HashLoc,
70 const Token &IncludeTok,
73 CharSourceRange FilenameRange,
74 const FileEntry *File,
76 StringRef RelativePath,
77 const Module *Imported,
78 SrcMgr::CharacteristicKind FileType) {
82 SourceManager &SM = PP->getSourceManager();
83 const FileEntry *FromFile
84 = SM.getFileEntryForID(SM.getFileID(SM.getExpansionLoc(HashLoc)));
88 Dependencies[FromFile].push_back(File);
90 AllFiles.insert(File);
91 AllFiles.insert(FromFile);
95 DependencyGraphCallback::writeNodeReference(raw_ostream &OS,
96 const FileEntry *Node) {
97 OS << "header_" << Node->getUID();
101 void DependencyGraphCallback::OutputGraphFile() {
103 llvm::raw_fd_ostream OS(OutputFile, EC, llvm::sys::fs::OF_Text);
105 PP->getDiagnostics().Report(diag::err_fe_error_opening) << OutputFile
110 OS << "digraph \"dependencies\" {\n";
113 for (unsigned I = 0, N = AllFiles.size(); I != N; ++I) {
114 // Write the node itself.
116 writeNodeReference(OS, AllFiles[I]);
117 OS << " [ shape=\"box\", label=\"";
118 StringRef FileName = AllFiles[I]->getName();
119 if (FileName.startswith(SysRoot))
120 FileName = FileName.substr(SysRoot.size());
122 OS << DOT::EscapeString(FileName)
127 for (DependencyMap::iterator F = Dependencies.begin(),
128 FEnd = Dependencies.end();
130 for (unsigned I = 0, N = F->second.size(); I != N; ++I) {
132 writeNodeReference(OS, F->first);
134 writeNodeReference(OS, F->second[I]);