clang-tools-extra/clang-move/Move.cpp

   1 //===-- Move.cpp - Implement ClangMove functationalities --------*- C++ -*-===//
   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 #include "Move.h"
  10 #include "HelperDeclRefGraph.h"
  11 #include "clang/ASTMatchers/ASTMatchers.h"
  12 #include "clang/Basic/SourceManager.h"
  13 #include "clang/Format/Format.h"
  14 #include "clang/Frontend/CompilerInstance.h"
  15 #include "clang/Lex/Lexer.h"
  16 #include "clang/Lex/Preprocessor.h"
  17 #include "clang/Rewrite/Core/Rewriter.h"
  18 #include "clang/Tooling/Core/Replacement.h"
  19 #include "llvm/Support/Debug.h"
  20 #include "llvm/Support/Path.h"
  21
  22 #define DEBUG_TYPE "clang-move"
  23
  24 using namespace clang::ast_matchers;
  25
  26 namespace clang {
  27 namespace move {
  28 namespace {
  29
  30 // FIXME: Move to ASTMatchers.
  31 AST_MATCHER(VarDecl, isStaticDataMember) { return Node.isStaticDataMember(); }
  32
  33 AST_MATCHER(NamedDecl, notInMacro) { return !Node.getLocation().isMacroID(); }
  34
  35 AST_MATCHER_P(Decl, hasOutermostEnclosingClass,
  36               ast_matchers::internal::Matcher<Decl>, InnerMatcher) {
  37   const auto *Context = Node.getDeclContext();
  38   if (!Context)
  39     return false;
  40   while (const auto *NextContext = Context->getParent()) {
  41     if (isa<NamespaceDecl>(NextContext) ||
  42         isa<TranslationUnitDecl>(NextContext))
  43       break;
  44     Context = NextContext;
  45   }
  46   return InnerMatcher.matches(*Decl::castFromDeclContext(Context), Finder,
  47                               Builder);
  48 }
  49
  50 AST_MATCHER_P(CXXMethodDecl, ofOutermostEnclosingClass,
  51               ast_matchers::internal::Matcher<CXXRecordDecl>, InnerMatcher) {
  52   const CXXRecordDecl *Parent = Node.getParent();
  53   if (!Parent)
  54     return false;
  55   while (const auto *NextParent =
  56              dyn_cast<CXXRecordDecl>(Parent->getParent())) {
  57     Parent = NextParent;
  58   }
  59
  60   return InnerMatcher.matches(*Parent, Finder, Builder);
  61 }
  62
  63 std::string CleanPath(StringRef PathRef) {
  64   llvm::SmallString<128> Path(PathRef);
  65   llvm::sys::path::remove_dots(Path, /*remove_dot_dot=*/true);
  66   // FIXME: figure out why this is necessary.
  67   llvm::sys::path::native(Path);
  68   return std::string(Path.str());
  69 }
  70
  71 // Make the Path absolute using the CurrentDir if the Path is not an absolute
  72 // path. An empty Path will result in an empty string.
  73 std::string MakeAbsolutePath(StringRef CurrentDir, StringRef Path) {
  74   if (Path.empty())
  75     return "";
  76   llvm::SmallString<128> InitialDirectory(CurrentDir);
  77   llvm::SmallString<128> AbsolutePath(Path);
  78   llvm::sys::fs::make_absolute(InitialDirectory, AbsolutePath);
  79   return CleanPath(std::move(AbsolutePath));
  80 }
  81
  82 // Make the Path absolute using the current working directory of the given
  83 // SourceManager if the Path is not an absolute path.
  84 //
  85 // The Path can be a path relative to the build directory, or retrieved from
  86 // the SourceManager.
  87 std::string MakeAbsolutePath(const SourceManager &SM, StringRef Path) {
  88   llvm::SmallString<128> AbsolutePath(Path);
  89   if (std::error_code EC =
  90           SM.getFileManager().getVirtualFileSystem().makeAbsolute(AbsolutePath))
  91     llvm::errs() << "Warning: could not make absolute file: '" << EC.message()
  92                  << '\n';
  93   // Handle symbolic link path cases.
  94   // We are trying to get the real file path of the symlink.
  95   auto Dir = SM.getFileManager().getOptionalDirectoryRef(
  96       llvm::sys::path::parent_path(AbsolutePath.str()));
  97   if (Dir) {
  98     StringRef DirName = SM.getFileManager().getCanonicalName(*Dir);
  99     // FIXME: getCanonicalName might fail to get real path on VFS.
 100     if (llvm::sys::path::is_absolute(DirName)) {
 101       SmallString<128> AbsoluteFilename;
 102       llvm::sys::path::append(AbsoluteFilename, DirName,
 103                               llvm::sys::path::filename(AbsolutePath.str()));
 104       return CleanPath(AbsoluteFilename);
 105     }
 106   }
 107   return CleanPath(AbsolutePath);
 108 }
 109
 110 // Matches AST nodes that are expanded within the given AbsoluteFilePath.
 111 AST_POLYMORPHIC_MATCHER_P(isExpansionInFile,
 112                           AST_POLYMORPHIC_SUPPORTED_TYPES(Decl, Stmt, TypeLoc),
 113                           std::string, AbsoluteFilePath) {
 114   auto &SourceManager = Finder->getASTContext().getSourceManager();
 115   auto ExpansionLoc = SourceManager.getExpansionLoc(Node.getBeginLoc());
 116   if (ExpansionLoc.isInvalid())
 117     return false;
 118   auto *FileEntry =
 119       SourceManager.getFileEntryForID(SourceManager.getFileID(ExpansionLoc));
 120   if (!FileEntry)
 121     return false;
 122   return MakeAbsolutePath(SourceManager, FileEntry->getName()) ==
 123          AbsoluteFilePath;
 124 }
 125
 126 class FindAllIncludes : public PPCallbacks {
 127 public:
 128   explicit FindAllIncludes(SourceManager *SM, ClangMoveTool *const MoveTool)
 129       : SM(*SM), MoveTool(MoveTool) {}
 130
 131   void InclusionDirective(SourceLocation HashLoc, const Token & /*IncludeTok*/,
 132                           StringRef FileName, bool IsAngled,
 133                           CharSourceRange FilenameRange,
 134                           OptionalFileEntryRef /*File*/, StringRef SearchPath,
 135                           StringRef /*RelativePath*/,
 136                           const Module * /*Imported*/,
 137                           SrcMgr::CharacteristicKind /*FileType*/) override {
 138     if (const auto *FileEntry = SM.getFileEntryForID(SM.getFileID(HashLoc)))
 139       MoveTool->addIncludes(FileName, IsAngled, SearchPath,
 140                             FileEntry->getName(), FilenameRange, SM);
 141   }
 142
 143 private:
 144   const SourceManager &SM;
 145   ClangMoveTool *const MoveTool;
 146 };
 147
 148 /// Add a declaration being moved to new.h/cc. Note that the declaration will
 149 /// also be deleted in old.h/cc.
 150 void MoveDeclFromOldFileToNewFile(ClangMoveTool *MoveTool, const NamedDecl *D) {
 151   MoveTool->getMovedDecls().push_back(D);
 152   MoveTool->addRemovedDecl(D);
 153   MoveTool->getUnremovedDeclsInOldHeader().erase(D);
 154 }
 155
 156 class FunctionDeclarationMatch : public MatchFinder::MatchCallback {
 157 public:
 158   explicit FunctionDeclarationMatch(ClangMoveTool *MoveTool)
 159       : MoveTool(MoveTool) {}
 160
 161   void run(const MatchFinder::MatchResult &Result) override {
 162     const auto *FD = Result.Nodes.getNodeAs<FunctionDecl>("function");
 163     assert(FD);
 164     const NamedDecl *D = FD;
 165     if (const auto *FTD = FD->getDescribedFunctionTemplate())
 166       D = FTD;
 167     MoveDeclFromOldFileToNewFile(MoveTool, D);
 168   }
 169
 170 private:
 171   ClangMoveTool *MoveTool;
 172 };
 173
 174 class VarDeclarationMatch : public MatchFinder::MatchCallback {
 175 public:
 176   explicit VarDeclarationMatch(ClangMoveTool *MoveTool)
 177       : MoveTool(MoveTool) {}
 178
 179   void run(const MatchFinder::MatchResult &Result) override {
 180     const auto *VD = Result.Nodes.getNodeAs<VarDecl>("var");
 181     assert(VD);
 182     MoveDeclFromOldFileToNewFile(MoveTool, VD);
 183   }
 184
 185 private:
 186   ClangMoveTool *MoveTool;
 187 };
 188
 189 class TypeAliasMatch : public MatchFinder::MatchCallback {
 190 public:
 191   explicit TypeAliasMatch(ClangMoveTool *MoveTool)
 192       : MoveTool(MoveTool) {}
 193
 194   void run(const MatchFinder::MatchResult &Result) override {
 195     if (const auto *TD = Result.Nodes.getNodeAs<TypedefDecl>("typedef"))
 196       MoveDeclFromOldFileToNewFile(MoveTool, TD);
 197     else if (const auto *TAD =
 198                  Result.Nodes.getNodeAs<TypeAliasDecl>("type_alias")) {
 199       const NamedDecl * D = TAD;
 200       if (const auto * TD = TAD->getDescribedAliasTemplate())
 201         D = TD;
 202       MoveDeclFromOldFileToNewFile(MoveTool, D);
 203     }
 204   }
 205
 206 private:
 207   ClangMoveTool *MoveTool;
 208 };
 209
 210 class EnumDeclarationMatch : public MatchFinder::MatchCallback {
 211 public:
 212   explicit EnumDeclarationMatch(ClangMoveTool *MoveTool)
 213       : MoveTool(MoveTool) {}
 214
 215   void run(const MatchFinder::MatchResult &Result) override {
 216     const auto *ED = Result.Nodes.getNodeAs<EnumDecl>("enum");
 217     assert(ED);
 218     MoveDeclFromOldFileToNewFile(MoveTool, ED);
 219   }
 220
 221 private:
 222   ClangMoveTool *MoveTool;
 223 };
 224
 225 class ClassDeclarationMatch : public MatchFinder::MatchCallback {
 226 public:
 227   explicit ClassDeclarationMatch(ClangMoveTool *MoveTool)
 228       : MoveTool(MoveTool) {}
 229   void run(const MatchFinder::MatchResult &Result) override {
 230     SourceManager *SM = &Result.Context->getSourceManager();
 231     if (const auto *CMD = Result.Nodes.getNodeAs<CXXMethodDecl>("class_method"))
 232       MatchClassMethod(CMD, SM);
 233     else if (const auto *VD =
 234                  Result.Nodes.getNodeAs<VarDecl>("class_static_var_decl"))
 235       MatchClassStaticVariable(VD, SM);
 236     else if (const auto *CD =
 237                  Result.Nodes.getNodeAs<CXXRecordDecl>("moved_class"))
 238       MatchClassDeclaration(CD, SM);
 239   }
 240
 241 private:
 242   void MatchClassMethod(const CXXMethodDecl *CMD, SourceManager *SM) {
 243     // Skip inline class methods. isInline() ast matcher doesn't ignore this
 244     // case.
 245     if (!CMD->isInlined()) {
 246       MoveTool->getMovedDecls().push_back(CMD);
 247       MoveTool->addRemovedDecl(CMD);
 248       // Get template class method from its method declaration as
 249       // UnremovedDecls stores template class method.
 250       if (const auto *FTD = CMD->getDescribedFunctionTemplate())
 251         MoveTool->getUnremovedDeclsInOldHeader().erase(FTD);
 252       else
 253         MoveTool->getUnremovedDeclsInOldHeader().erase(CMD);
 254     }
 255   }
 256
 257   void MatchClassStaticVariable(const NamedDecl *VD, SourceManager *SM) {
 258     MoveDeclFromOldFileToNewFile(MoveTool, VD);
 259   }
 260
 261   void MatchClassDeclaration(const CXXRecordDecl *CD, SourceManager *SM) {
 262     // Get class template from its class declaration as UnremovedDecls stores
 263     // class template.
 264     if (const auto *TC = CD->getDescribedClassTemplate())
 265       MoveTool->getMovedDecls().push_back(TC);
 266     else
 267       MoveTool->getMovedDecls().push_back(CD);
 268     MoveTool->addRemovedDecl(MoveTool->getMovedDecls().back());
 269     MoveTool->getUnremovedDeclsInOldHeader().erase(
 270         MoveTool->getMovedDecls().back());
 271   }
 272
 273   ClangMoveTool *MoveTool;
 274 };
 275
 276 // Expand to get the end location of the line where the EndLoc of the given
 277 // Decl.
 278 SourceLocation getLocForEndOfDecl(const Decl *D,
 279                                   const LangOptions &LangOpts = LangOptions()) {
 280   const auto &SM = D->getASTContext().getSourceManager();
 281   // If the expansion range is a character range, this is the location of
 282   // the first character past the end. Otherwise it's the location of the
 283   // first character in the final token in the range.
 284   auto EndExpansionLoc = SM.getExpansionRange(D->getEndLoc()).getEnd();
 285   std::pair<FileID, unsigned> LocInfo = SM.getDecomposedLoc(EndExpansionLoc);
 286   // Try to load the file buffer.
 287   bool InvalidTemp = false;
 288   llvm::StringRef File = SM.getBufferData(LocInfo.first, &InvalidTemp);
 289   if (InvalidTemp)
 290     return SourceLocation();
 291
 292   const char *TokBegin = File.data() + LocInfo.second;
 293   // Lex from the start of the given location.
 294   Lexer Lex(SM.getLocForStartOfFile(LocInfo.first), LangOpts, File.begin(),
 295             TokBegin, File.end());
 296
 297   llvm::SmallVector<char, 16> Line;
 298   // FIXME: this is a bit hacky to get ReadToEndOfLine work.
 299   Lex.setParsingPreprocessorDirective(true);
 300   Lex.ReadToEndOfLine(&Line);
 301   SourceLocation EndLoc = EndExpansionLoc.getLocWithOffset(Line.size());
 302   // If we already reach EOF, just return the EOF SourceLocation;
 303   // otherwise, move 1 offset ahead to include the trailing newline character
 304   // '\n'.
 305   return SM.getLocForEndOfFile(LocInfo.first) == EndLoc
 306              ? EndLoc
 307              : EndLoc.getLocWithOffset(1);
 308 }
 309
 310 // Get full range of a Decl including the comments associated with it.
 311 CharSourceRange getFullRange(const Decl *D,
 312                              const LangOptions &options = LangOptions()) {
 313   const auto &SM = D->getASTContext().getSourceManager();
 314   SourceRange Full(SM.getExpansionLoc(D->getBeginLoc()), getLocForEndOfDecl(D));
 315   // Expand to comments that are associated with the Decl.
 316   if (const auto *Comment = D->getASTContext().getRawCommentForDeclNoCache(D)) {
 317     if (SM.isBeforeInTranslationUnit(Full.getEnd(), Comment->getEndLoc()))
 318       Full.setEnd(Comment->getEndLoc());
 319     // FIXME: Don't delete a preceding comment, if there are no other entities
 320     // it could refer to.
 321     if (SM.isBeforeInTranslationUnit(Comment->getBeginLoc(), Full.getBegin()))
 322       Full.setBegin(Comment->getBeginLoc());
 323   }
 324
 325   return CharSourceRange::getCharRange(Full);
 326 }
 327
 328 std::string getDeclarationSourceText(const Decl *D) {
 329   const auto &SM = D->getASTContext().getSourceManager();
 330   llvm::StringRef SourceText =
 331       Lexer::getSourceText(getFullRange(D), SM, LangOptions());
 332   return SourceText.str();
 333 }
 334
 335 bool isInHeaderFile(const Decl *D, llvm::StringRef OriginalRunningDirectory,
 336                     llvm::StringRef OldHeader) {
 337   const auto &SM = D->getASTContext().getSourceManager();
 338   if (OldHeader.empty())
 339     return false;
 340   auto ExpansionLoc = SM.getExpansionLoc(D->getBeginLoc());
 341   if (ExpansionLoc.isInvalid())
 342     return false;
 343
 344   if (const auto *FE = SM.getFileEntryForID(SM.getFileID(ExpansionLoc))) {
 345     return MakeAbsolutePath(SM, FE->getName()) ==
 346            MakeAbsolutePath(OriginalRunningDirectory, OldHeader);
 347   }
 348
 349   return false;
 350 }
 351
 352 std::vector<std::string> getNamespaces(const Decl *D) {
 353   std::vector<std::string> Namespaces;
 354   for (const auto *Context = D->getDeclContext(); Context;
 355        Context = Context->getParent()) {
 356     if (llvm::isa<TranslationUnitDecl>(Context) ||
 357         llvm::isa<LinkageSpecDecl>(Context))
 358       break;
 359
 360     if (const auto *ND = llvm::dyn_cast<NamespaceDecl>(Context))
 361       Namespaces.push_back(ND->getName().str());
 362   }
 363   std::reverse(Namespaces.begin(), Namespaces.end());
 364   return Namespaces;
 365 }
 366
 367 tooling::Replacements
 368 createInsertedReplacements(const std::vector<std::string> &Includes,
 369                            const std::vector<const NamedDecl *> &Decls,
 370                            llvm::StringRef FileName, bool IsHeader = false,
 371                            StringRef OldHeaderInclude = "") {
 372   std::string NewCode;
 373   std::string GuardName(FileName);
 374   if (IsHeader) {
 375     for (size_t i = 0; i < GuardName.size(); ++i) {
 376       if (!isAlphanumeric(GuardName[i]))
 377         GuardName[i] = '_';
 378     }
 379     GuardName = StringRef(GuardName).upper();
 380     NewCode += "#ifndef " + GuardName + "\n";
 381     NewCode += "#define " + GuardName + "\n\n";
 382   }
 383
 384   NewCode += OldHeaderInclude;
 385   // Add #Includes.
 386   for (const auto &Include : Includes)
 387     NewCode += Include;
 388
 389   if (!Includes.empty())
 390     NewCode += "\n";
 391
 392   // Add moved class definition and its related declarations. All declarations
 393   // in same namespace are grouped together.
 394   //
 395   // Record namespaces where the current position is in.
 396   std::vector<std::string> CurrentNamespaces;
 397   for (const auto *MovedDecl : Decls) {
 398     // The namespaces of the declaration being moved.
 399     std::vector<std::string> DeclNamespaces = getNamespaces(MovedDecl);
 400     auto CurrentIt = CurrentNamespaces.begin();
 401     auto DeclIt = DeclNamespaces.begin();
 402     // Skip the common prefix.
 403     while (CurrentIt != CurrentNamespaces.end() &&
 404            DeclIt != DeclNamespaces.end()) {
 405       if (*CurrentIt != *DeclIt)
 406         break;
 407       ++CurrentIt;
 408       ++DeclIt;
 409     }
 410     // Calculate the new namespaces after adding MovedDecl in CurrentNamespace,
 411     // which is used for next iteration of this loop.
 412     std::vector<std::string> NextNamespaces(CurrentNamespaces.begin(),
 413                                             CurrentIt);
 414     NextNamespaces.insert(NextNamespaces.end(), DeclIt, DeclNamespaces.end());
 415
 416
 417     // End with CurrentNamespace.
 418     bool HasEndCurrentNamespace = false;
 419     auto RemainingSize = CurrentNamespaces.end() - CurrentIt;
 420     for (auto It = CurrentNamespaces.rbegin(); RemainingSize > 0;
 421          --RemainingSize, ++It) {
 422       assert(It < CurrentNamespaces.rend());
 423       NewCode += "} // namespace " + *It + "\n";
 424       HasEndCurrentNamespace = true;
 425     }
 426     // Add trailing '\n' after the nested namespace definition.
 427     if (HasEndCurrentNamespace)
 428       NewCode += "\n";
 429
 430     // If the moved declaration is not in CurrentNamespace, add extra namespace
 431     // definitions.
 432     bool IsInNewNamespace = false;
 433     while (DeclIt != DeclNamespaces.end()) {
 434       NewCode += "namespace " + *DeclIt + " {\n";
 435       IsInNewNamespace = true;
 436       ++DeclIt;
 437     }
 438     // If the moved declaration is in same namespace CurrentNamespace, add
 439     // a preceeding `\n' before the moved declaration.
 440     // FIXME: Don't add empty lines between using declarations.
 441     if (!IsInNewNamespace)
 442       NewCode += "\n";
 443     NewCode += getDeclarationSourceText(MovedDecl);
 444     CurrentNamespaces = std::move(NextNamespaces);
 445   }
 446   std::reverse(CurrentNamespaces.begin(), CurrentNamespaces.end());
 447   for (const auto &NS : CurrentNamespaces)
 448     NewCode += "} // namespace " + NS + "\n";
 449
 450   if (IsHeader)
 451     NewCode += "\n#endif // " + GuardName + "\n";
 452   return tooling::Replacements(tooling::Replacement(FileName, 0, 0, NewCode));
 453 }
 454
 455 // Return a set of all decls which are used/referenced by the given Decls.
 456 // Specifically, given a class member declaration, this method will return all
 457 // decls which are used by the whole class.
 458 llvm::DenseSet<const Decl *>
 459 getUsedDecls(const HelperDeclRefGraph *RG,
 460              const std::vector<const NamedDecl *> &Decls) {
 461   assert(RG);
 462   llvm::DenseSet<const CallGraphNode *> Nodes;
 463   for (const auto *D : Decls) {
 464     auto Result = RG->getReachableNodes(
 465         HelperDeclRGBuilder::getOutmostClassOrFunDecl(D));
 466     Nodes.insert(Result.begin(), Result.end());
 467   }
 468   llvm::DenseSet<const Decl *> Results;
 469   for (const auto *Node : Nodes)
 470     Results.insert(Node->getDecl());
 471   return Results;
 472 }
 473
 474 } // namespace
 475
 476 std::unique_ptr<ASTConsumer>
 477 ClangMoveAction::CreateASTConsumer(CompilerInstance &Compiler,
 478                                    StringRef /*InFile*/) {
 479   Compiler.getPreprocessor().addPPCallbacks(std::make_unique<FindAllIncludes>(
 480       &Compiler.getSourceManager(), &MoveTool));
 481   return MatchFinder.newASTConsumer();
 482 }
 483
 484 ClangMoveTool::ClangMoveTool(ClangMoveContext *const Context,
 485                              DeclarationReporter *const Reporter)
 486     : Context(Context), Reporter(Reporter) {
 487   if (!Context->Spec.NewHeader.empty())
 488     CCIncludes.push_back("#include \"" + Context->Spec.NewHeader + "\"\n");
 489 }
 490
 491 void ClangMoveTool::addRemovedDecl(const NamedDecl *Decl) {
 492   const auto &SM = Decl->getASTContext().getSourceManager();
 493   auto Loc = Decl->getLocation();
 494   StringRef FilePath = SM.getFilename(Loc);
 495   FilePathToFileID[FilePath] = SM.getFileID(Loc);
 496   RemovedDecls.push_back(Decl);
 497 }
 498
 499 void ClangMoveTool::registerMatchers(ast_matchers::MatchFinder *Finder) {
 500   auto InOldHeader =
 501       isExpansionInFile(makeAbsolutePath(Context->Spec.OldHeader));
 502   auto InOldCC = isExpansionInFile(makeAbsolutePath(Context->Spec.OldCC));
 503   auto InOldFiles = anyOf(InOldHeader, InOldCC);
 504   auto classTemplateForwardDecls =
 505       classTemplateDecl(unless(has(cxxRecordDecl(isDefinition()))));
 506   auto ForwardClassDecls = namedDecl(
 507       anyOf(cxxRecordDecl(unless(anyOf(isImplicit(), isDefinition()))),
 508             classTemplateForwardDecls));
 509   auto TopLevelDecl =
 510       hasDeclContext(anyOf(namespaceDecl(), translationUnitDecl()));
 511
 512   //============================================================================
 513   // Matchers for old header
 514   //============================================================================
 515   // Match all top-level named declarations (e.g. function, variable, enum) in
 516   // old header, exclude forward class declarations and namespace declarations.
 517   //
 518   // We consider declarations inside a class belongs to the class. So these
 519   // declarations will be ignored.
 520   auto AllDeclsInHeader = namedDecl(
 521       unless(ForwardClassDecls), unless(namespaceDecl()),
 522       unless(usingDirectiveDecl()), // using namespace decl.
 523       notInMacro(),
 524       InOldHeader,
 525       hasParent(decl(anyOf(namespaceDecl(), translationUnitDecl()))),
 526       hasDeclContext(decl(anyOf(namespaceDecl(), translationUnitDecl()))));
 527   Finder->addMatcher(AllDeclsInHeader.bind("decls_in_header"), this);
 528
 529   // Don't register other matchers when dumping all declarations in header.
 530   if (Context->DumpDeclarations)
 531     return;
 532
 533   // Match forward declarations in old header.
 534   Finder->addMatcher(namedDecl(ForwardClassDecls, InOldHeader).bind("fwd_decl"),
 535                      this);
 536
 537   //============================================================================
 538   // Matchers for old cc
 539   //============================================================================
 540   auto IsOldCCTopLevelDecl = allOf(
 541       hasParent(decl(anyOf(namespaceDecl(), translationUnitDecl()))), InOldCC);
 542   // Matching using decls/type alias decls which are in named/anonymous/global
 543   // namespace, these decls are always copied to new.h/cc. Those in classes,
 544   // functions are covered in other matchers.
 545   Finder->addMatcher(namedDecl(anyOf(usingDecl(IsOldCCTopLevelDecl),
 546                                      usingDirectiveDecl(unless(isImplicit()),
 547                                                         IsOldCCTopLevelDecl),
 548                                      typeAliasDecl(IsOldCCTopLevelDecl)),
 549                                notInMacro())
 550                          .bind("using_decl"),
 551                      this);
 552
 553   // Match static functions/variable definitions which are defined in named
 554   // namespaces.
 555   SmallVector<std::string, 4> QualNames;
 556   QualNames.reserve(Context->Spec.Names.size());
 557   for (StringRef SymbolName : Context->Spec.Names) {
 558     QualNames.push_back(("::" + SymbolName.trim().ltrim(':')).str());
 559   }
 560
 561   if (QualNames.empty()) {
 562     llvm::errs() << "No symbols being moved.\n";
 563     return;
 564   }
 565
 566   ast_matchers::internal::Matcher<NamedDecl> HasAnySymbolNames =
 567       hasAnyName(SmallVector<StringRef, 4>(QualNames.begin(), QualNames.end()));
 568
 569   auto InMovedClass =
 570       hasOutermostEnclosingClass(cxxRecordDecl(HasAnySymbolNames));
 571
 572   // Matchers for helper declarations in old.cc.
 573   auto InAnonymousNS = hasParent(namespaceDecl(isAnonymous()));
 574   auto NotInMovedClass= allOf(unless(InMovedClass), InOldCC);
 575   auto IsOldCCHelper =
 576       allOf(NotInMovedClass, anyOf(isStaticStorageClass(), InAnonymousNS));
 577   // Match helper classes separately with helper functions/variables since we
 578   // want to reuse these matchers in finding helpers usage below.
 579   //
 580   // There could be forward declarations usage for helpers, especially for
 581   // classes and functions. We need include these forward declarations.
 582   //
 583   // Forward declarations for variable helpers will be excluded as these
 584   // declarations (with "extern") are not supposed in cpp file.
 585    auto HelperFuncOrVar =
 586       namedDecl(notInMacro(), anyOf(functionDecl(IsOldCCHelper),
 587                                     varDecl(isDefinition(), IsOldCCHelper)));
 588   auto HelperClasses =
 589       cxxRecordDecl(notInMacro(), NotInMovedClass, InAnonymousNS);
 590   // Save all helper declarations in old.cc.
 591   Finder->addMatcher(
 592       namedDecl(anyOf(HelperFuncOrVar, HelperClasses)).bind("helper_decls"),
 593       this);
 594
 595   // Construct an AST-based call graph of helper declarations in old.cc.
 596   // In the following matcheres, "dc" is a caller while "helper_decls" and
 597   // "used_class" is a callee, so a new edge starting from caller to callee will
 598   // be add in the graph.
 599   //
 600   // Find helper function/variable usages.
 601   Finder->addMatcher(
 602       declRefExpr(to(HelperFuncOrVar), hasAncestor(decl().bind("dc")))
 603           .bind("func_ref"),
 604       &RGBuilder);
 605   // Find helper class usages.
 606   Finder->addMatcher(
 607       typeLoc(loc(recordType(hasDeclaration(HelperClasses.bind("used_class")))),
 608               hasAncestor(decl().bind("dc"))),
 609       &RGBuilder);
 610
 611   //============================================================================
 612   // Matchers for old files, including old.h/old.cc
 613   //============================================================================
 614   // Create a MatchCallback for class declarations.
 615   MatchCallbacks.push_back(std::make_unique<ClassDeclarationMatch>(this));
 616   // Match moved class declarations.
 617   auto MovedClass =
 618       cxxRecordDecl(InOldFiles, HasAnySymbolNames, isDefinition(), TopLevelDecl)
 619           .bind("moved_class");
 620   Finder->addMatcher(MovedClass, MatchCallbacks.back().get());
 621   // Match moved class methods (static methods included) which are defined
 622   // outside moved class declaration.
 623   Finder->addMatcher(cxxMethodDecl(InOldFiles,
 624                                    ofOutermostEnclosingClass(HasAnySymbolNames),
 625                                    isDefinition())
 626                          .bind("class_method"),
 627                      MatchCallbacks.back().get());
 628   // Match static member variable definition of the moved class.
 629   Finder->addMatcher(
 630       varDecl(InMovedClass, InOldFiles, isDefinition(), isStaticDataMember())
 631           .bind("class_static_var_decl"),
 632       MatchCallbacks.back().get());
 633
 634   MatchCallbacks.push_back(std::make_unique<FunctionDeclarationMatch>(this));
 635   Finder->addMatcher(functionDecl(InOldFiles, HasAnySymbolNames, TopLevelDecl)
 636                          .bind("function"),
 637                      MatchCallbacks.back().get());
 638
 639   MatchCallbacks.push_back(std::make_unique<VarDeclarationMatch>(this));
 640   Finder->addMatcher(
 641       varDecl(InOldFiles, HasAnySymbolNames, TopLevelDecl).bind("var"),
 642       MatchCallbacks.back().get());
 643
 644   // Match enum definition in old.h. Enum helpers (which are defined in old.cc)
 645   // will not be moved for now no matter whether they are used or not.
 646   MatchCallbacks.push_back(std::make_unique<EnumDeclarationMatch>(this));
 647   Finder->addMatcher(
 648       enumDecl(InOldHeader, HasAnySymbolNames, isDefinition(), TopLevelDecl)
 649           .bind("enum"),
 650       MatchCallbacks.back().get());
 651
 652   // Match type alias in old.h, this includes "typedef" and "using" type alias
 653   // declarations. Type alias helpers (which are defined in old.cc) will not be
 654   // moved for now no matter whether they are used or not.
 655   MatchCallbacks.push_back(std::make_unique<TypeAliasMatch>(this));
 656   Finder->addMatcher(namedDecl(anyOf(typedefDecl().bind("typedef"),
 657                                      typeAliasDecl().bind("type_alias")),
 658                                InOldHeader, HasAnySymbolNames, TopLevelDecl),
 659                      MatchCallbacks.back().get());
 660 }
 661
 662 void ClangMoveTool::run(const ast_matchers::MatchFinder::MatchResult &Result) {
 663   if (const auto *D = Result.Nodes.getNodeAs<NamedDecl>("decls_in_header")) {
 664     UnremovedDeclsInOldHeader.insert(D);
 665   } else if (const auto *FWD =
 666                  Result.Nodes.getNodeAs<CXXRecordDecl>("fwd_decl")) {
 667     // Skip all forward declarations which appear after moved class declaration.
 668     if (RemovedDecls.empty()) {
 669       if (const auto *DCT = FWD->getDescribedClassTemplate())
 670         MovedDecls.push_back(DCT);
 671       else
 672         MovedDecls.push_back(FWD);
 673     }
 674   } else if (const auto *ND =
 675                  Result.Nodes.getNodeAs<NamedDecl>("helper_decls")) {
 676     MovedDecls.push_back(ND);
 677     HelperDeclarations.push_back(ND);
 678     LLVM_DEBUG(llvm::dbgs()
 679                << "Add helper : " << ND->getDeclName() << " (" << ND << ")\n");
 680   } else if (const auto *UD = Result.Nodes.getNodeAs<NamedDecl>("using_decl")) {
 681     MovedDecls.push_back(UD);
 682   }
 683 }
 684
 685 std::string ClangMoveTool::makeAbsolutePath(StringRef Path) {
 686   return MakeAbsolutePath(Context->OriginalRunningDirectory, Path);
 687 }
 688
 689 void ClangMoveTool::addIncludes(llvm::StringRef IncludeHeader, bool IsAngled,
 690                                 llvm::StringRef SearchPath,
 691                                 llvm::StringRef FileName,
 692                                 CharSourceRange IncludeFilenameRange,
 693                                 const SourceManager &SM) {
 694   SmallString<128> HeaderWithSearchPath;
 695   llvm::sys::path::append(HeaderWithSearchPath, SearchPath, IncludeHeader);
 696   std::string AbsoluteIncludeHeader =
 697       MakeAbsolutePath(SM, HeaderWithSearchPath);
 698   std::string IncludeLine =
 699       IsAngled ? ("#include <" + IncludeHeader + ">\n").str()
 700                : ("#include \"" + IncludeHeader + "\"\n").str();
 701
 702   std::string AbsoluteOldHeader = makeAbsolutePath(Context->Spec.OldHeader);
 703   std::string AbsoluteCurrentFile = MakeAbsolutePath(SM, FileName);
 704   if (AbsoluteOldHeader == AbsoluteCurrentFile) {
 705     // Find old.h includes "old.h".
 706     if (AbsoluteOldHeader == AbsoluteIncludeHeader) {
 707       OldHeaderIncludeRangeInHeader = IncludeFilenameRange;
 708       return;
 709     }
 710     HeaderIncludes.push_back(IncludeLine);
 711   } else if (makeAbsolutePath(Context->Spec.OldCC) == AbsoluteCurrentFile) {
 712     // Find old.cc includes "old.h".
 713     if (AbsoluteOldHeader == AbsoluteIncludeHeader) {
 714       OldHeaderIncludeRangeInCC = IncludeFilenameRange;
 715       return;
 716     }
 717     CCIncludes.push_back(IncludeLine);
 718   }
 719 }
 720
 721 void ClangMoveTool::removeDeclsInOldFiles() {
 722   if (RemovedDecls.empty()) return;
 723
 724   // If old_header is not specified (only move declarations from old.cc), remain
 725   // all the helper function declarations in old.cc as UnremovedDeclsInOldHeader
 726   // is empty in this case, there is no way to verify unused/used helpers.
 727   if (!Context->Spec.OldHeader.empty()) {
 728     std::vector<const NamedDecl *> UnremovedDecls;
 729     for (const auto *D : UnremovedDeclsInOldHeader)
 730       UnremovedDecls.push_back(D);
 731
 732     auto UsedDecls = getUsedDecls(RGBuilder.getGraph(), UnremovedDecls);
 733
 734     // We remove the helper declarations which are not used in the old.cc after
 735     // moving the given declarations.
 736     for (const auto *D : HelperDeclarations) {
 737       LLVM_DEBUG(llvm::dbgs() << "Check helper is used: " << D->getDeclName()
 738                               << " (" << D << ")\n");
 739       if (!UsedDecls.count(HelperDeclRGBuilder::getOutmostClassOrFunDecl(
 740               D->getCanonicalDecl()))) {
 741         LLVM_DEBUG(llvm::dbgs() << "Helper removed in old.cc: "
 742                                 << D->getDeclName() << " (" << D << ")\n");
 743         RemovedDecls.push_back(D);
 744       }
 745     }
 746   }
 747
 748   for (const auto *RemovedDecl : RemovedDecls) {
 749     const auto &SM = RemovedDecl->getASTContext().getSourceManager();
 750     auto Range = getFullRange(RemovedDecl);
 751     tooling::Replacement RemoveReplacement(
 752         SM, CharSourceRange::getCharRange(Range.getBegin(), Range.getEnd()),
 753         "");
 754     std::string FilePath = RemoveReplacement.getFilePath().str();
 755     auto Err = Context->FileToReplacements[FilePath].add(RemoveReplacement);
 756     if (Err)
 757       llvm::errs() << llvm::toString(std::move(Err)) << "\n";
 758   }
 759   const auto &SM = RemovedDecls[0]->getASTContext().getSourceManager();
 760
 761   // Post process of cleanup around all the replacements.
 762   for (auto &FileAndReplacements : Context->FileToReplacements) {
 763     StringRef FilePath = FileAndReplacements.first;
 764     // Add #include of new header to old header.
 765     if (Context->Spec.OldDependOnNew &&
 766         MakeAbsolutePath(SM, FilePath) ==
 767             makeAbsolutePath(Context->Spec.OldHeader)) {
 768       // FIXME: Minimize the include path like clang-include-fixer.
 769       std::string IncludeNewH =
 770           "#include \"" + Context->Spec.NewHeader + "\"\n";
 771       // This replacement for inserting header will be cleaned up at the end.
 772       auto Err = FileAndReplacements.second.add(
 773           tooling::Replacement(FilePath, UINT_MAX, 0, IncludeNewH));
 774       if (Err)
 775         llvm::errs() << llvm::toString(std::move(Err)) << "\n";
 776     }
 777
 778     auto SI = FilePathToFileID.find(FilePath);
 779     // Ignore replacements for new.h/cc.
 780     if (SI == FilePathToFileID.end()) continue;
 781     llvm::StringRef Code = SM.getBufferData(SI->second);
 782     auto Style = format::getStyle(format::DefaultFormatStyle, FilePath,
 783                                   Context->FallbackStyle);
 784     if (!Style) {
 785       llvm::errs() << llvm::toString(Style.takeError()) << "\n";
 786       continue;
 787     }
 788     auto CleanReplacements = format::cleanupAroundReplacements(
 789         Code, Context->FileToReplacements[std::string(FilePath)], *Style);
 790
 791     if (!CleanReplacements) {
 792       llvm::errs() << llvm::toString(CleanReplacements.takeError()) << "\n";
 793       continue;
 794     }
 795     Context->FileToReplacements[std::string(FilePath)] = *CleanReplacements;
 796   }
 797 }
 798
 799 void ClangMoveTool::moveDeclsToNewFiles() {
 800   std::vector<const NamedDecl *> NewHeaderDecls;
 801   std::vector<const NamedDecl *> NewCCDecls;
 802   for (const auto *MovedDecl : MovedDecls) {
 803     if (isInHeaderFile(MovedDecl, Context->OriginalRunningDirectory,
 804                        Context->Spec.OldHeader))
 805       NewHeaderDecls.push_back(MovedDecl);
 806     else
 807       NewCCDecls.push_back(MovedDecl);
 808   }
 809
 810   auto UsedDecls = getUsedDecls(RGBuilder.getGraph(), RemovedDecls);
 811   std::vector<const NamedDecl *> ActualNewCCDecls;
 812
 813   // Filter out all unused helpers in NewCCDecls.
 814   // We only move the used helpers (including transitively used helpers) and the
 815   // given symbols being moved.
 816   for (const auto *D : NewCCDecls) {
 817     if (llvm::is_contained(HelperDeclarations, D) &&
 818         !UsedDecls.count(HelperDeclRGBuilder::getOutmostClassOrFunDecl(
 819             D->getCanonicalDecl())))
 820       continue;
 821
 822     LLVM_DEBUG(llvm::dbgs() << "Helper used in new.cc: " << D->getDeclName()
 823                             << " " << D << "\n");
 824     ActualNewCCDecls.push_back(D);
 825   }
 826
 827   if (!Context->Spec.NewHeader.empty()) {
 828     std::string OldHeaderInclude =
 829         Context->Spec.NewDependOnOld
 830             ? "#include \"" + Context->Spec.OldHeader + "\"\n"
 831             : "";
 832     Context->FileToReplacements[Context->Spec.NewHeader] =
 833         createInsertedReplacements(HeaderIncludes, NewHeaderDecls,
 834                                    Context->Spec.NewHeader, /*IsHeader=*/true,
 835                                    OldHeaderInclude);
 836   }
 837   if (!Context->Spec.NewCC.empty())
 838     Context->FileToReplacements[Context->Spec.NewCC] =
 839         createInsertedReplacements(CCIncludes, ActualNewCCDecls,
 840                                    Context->Spec.NewCC);
 841 }
 842
 843 // Move all contents from OldFile to NewFile.
 844 void ClangMoveTool::moveAll(SourceManager &SM, StringRef OldFile,
 845                             StringRef NewFile) {
 846   auto FE = SM.getFileManager().getFile(makeAbsolutePath(OldFile));
 847   if (!FE) {
 848     llvm::errs() << "Failed to get file: " << OldFile << "\n";
 849     return;
 850   }
 851   FileID ID = SM.getOrCreateFileID(*FE, SrcMgr::C_User);
 852   auto Begin = SM.getLocForStartOfFile(ID);
 853   auto End = SM.getLocForEndOfFile(ID);
 854   tooling::Replacement RemoveAll(SM, CharSourceRange::getCharRange(Begin, End),
 855                                  "");
 856   std::string FilePath = RemoveAll.getFilePath().str();
 857   Context->FileToReplacements[FilePath] = tooling::Replacements(RemoveAll);
 858
 859   StringRef Code = SM.getBufferData(ID);
 860   if (!NewFile.empty()) {
 861     auto AllCode =
 862         tooling::Replacements(tooling::Replacement(NewFile, 0, 0, Code));
 863     auto ReplaceOldInclude = [&](CharSourceRange OldHeaderIncludeRange) {
 864       AllCode = AllCode.merge(tooling::Replacements(tooling::Replacement(
 865           SM, OldHeaderIncludeRange, '"' + Context->Spec.NewHeader + '"')));
 866     };
 867     // Fix the case where old.h/old.cc includes "old.h", we replace the
 868     // `#include "old.h"` with `#include "new.h"`.
 869     if (Context->Spec.NewCC == NewFile && OldHeaderIncludeRangeInCC.isValid())
 870       ReplaceOldInclude(OldHeaderIncludeRangeInCC);
 871     else if (Context->Spec.NewHeader == NewFile &&
 872              OldHeaderIncludeRangeInHeader.isValid())
 873       ReplaceOldInclude(OldHeaderIncludeRangeInHeader);
 874     Context->FileToReplacements[std::string(NewFile)] = std::move(AllCode);
 875   }
 876 }
 877
 878 void ClangMoveTool::onEndOfTranslationUnit() {
 879   if (Context->DumpDeclarations) {
 880     assert(Reporter);
 881     for (const auto *Decl : UnremovedDeclsInOldHeader) {
 882       auto Kind = Decl->getKind();
 883       bool Templated = Decl->isTemplated();
 884       const std::string QualifiedName = Decl->getQualifiedNameAsString();
 885       if (Kind == Decl::Kind::Var)
 886         Reporter->reportDeclaration(QualifiedName, "Variable", Templated);
 887       else if (Kind == Decl::Kind::Function ||
 888                Kind == Decl::Kind::FunctionTemplate)
 889         Reporter->reportDeclaration(QualifiedName, "Function", Templated);
 890       else if (Kind == Decl::Kind::ClassTemplate ||
 891                Kind == Decl::Kind::CXXRecord)
 892         Reporter->reportDeclaration(QualifiedName, "Class", Templated);
 893       else if (Kind == Decl::Kind::Enum)
 894         Reporter->reportDeclaration(QualifiedName, "Enum", Templated);
 895       else if (Kind == Decl::Kind::Typedef || Kind == Decl::Kind::TypeAlias ||
 896                Kind == Decl::Kind::TypeAliasTemplate)
 897         Reporter->reportDeclaration(QualifiedName, "TypeAlias", Templated);
 898     }
 899     return;
 900   }
 901
 902   if (RemovedDecls.empty())
 903     return;
 904   // Ignore symbols that are not supported when checking if there is unremoved
 905   // symbol in old header. This makes sure that we always move old files to new
 906   // files when all symbols produced from dump_decls are moved.
 907   auto IsSupportedKind = [](const NamedDecl *Decl) {
 908     switch (Decl->getKind()) {
 909     case Decl::Kind::Function:
 910     case Decl::Kind::FunctionTemplate:
 911     case Decl::Kind::ClassTemplate:
 912     case Decl::Kind::CXXRecord:
 913     case Decl::Kind::Enum:
 914     case Decl::Kind::Typedef:
 915     case Decl::Kind::TypeAlias:
 916     case Decl::Kind::TypeAliasTemplate:
 917     case Decl::Kind::Var:
 918       return true;
 919     default:
 920       return false;
 921     }
 922   };
 923   if (llvm::none_of(UnremovedDeclsInOldHeader, IsSupportedKind) &&
 924       !Context->Spec.OldHeader.empty()) {
 925     auto &SM = RemovedDecls[0]->getASTContext().getSourceManager();
 926     moveAll(SM, Context->Spec.OldHeader, Context->Spec.NewHeader);
 927     moveAll(SM, Context->Spec.OldCC, Context->Spec.NewCC);
 928     return;
 929   }
 930   LLVM_DEBUG(RGBuilder.getGraph()->dump());
 931   moveDeclsToNewFiles();
 932   removeDeclsInOldFiles();
 933 }
 934
 935 } // namespace move
 936 } // namespace clang