clang/tools/clang-extdef-mapping/ClangExtDefMapGen.cpp

   1 //===- ClangExtDefMapGen.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 // Clang tool which creates a list of defined functions and the files in which
  10 // they are defined.
  11 //
  12 //===--------------------------------------------------------------------===//
  13
  14 #include "clang/AST/ASTConsumer.h"
  15 #include "clang/AST/ASTContext.h"
  16 #include "clang/Basic/DiagnosticOptions.h"
  17 #include "clang/Basic/SourceManager.h"
  18 #include "clang/CrossTU/CrossTranslationUnit.h"
  19 #include "clang/Frontend/CompilerInstance.h"
  20 #include "clang/Frontend/FrontendActions.h"
  21 #include "clang/Frontend/TextDiagnosticPrinter.h"
  22 #include "clang/Tooling/CommonOptionsParser.h"
  23 #include "clang/Tooling/Tooling.h"
  24 #include "llvm/Support/CommandLine.h"
  25 #include "llvm/Support/Signals.h"
  26 #include "llvm/Support/TargetSelect.h"
  27 #include <optional>
  28 #include <sstream>
  29 #include <string>
  30
  31 using namespace llvm;
  32 using namespace clang;
  33 using namespace clang::cross_tu;
  34 using namespace clang::tooling;
  35
  36 static cl::OptionCategory
  37     ClangExtDefMapGenCategory("clang-extdefmapgen options");
  38
  39 class MapExtDefNamesConsumer : public ASTConsumer {
  40 public:
  41   MapExtDefNamesConsumer(ASTContext &Context,
  42                          StringRef astFilePath = StringRef())
  43       : Ctx(Context), SM(Context.getSourceManager()) {
  44     CurrentFileName = astFilePath.str();
  45   }
  46
  47   ~MapExtDefNamesConsumer() {
  48     // Flush results to standard output.
  49     llvm::outs() << createCrossTUIndexString(Index);
  50   }
  51
  52   void HandleTranslationUnit(ASTContext &Context) override {
  53     handleDecl(Context.getTranslationUnitDecl());
  54   }
  55
  56 private:
  57   void handleDecl(const Decl *D);
  58   void addIfInMain(const DeclaratorDecl *DD, SourceLocation defStart);
  59
  60   ASTContext &Ctx;
  61   SourceManager &SM;
  62   llvm::StringMap<std::string> Index;
  63   std::string CurrentFileName;
  64 };
  65
  66 void MapExtDefNamesConsumer::handleDecl(const Decl *D) {
  67   if (!D)
  68     return;
  69
  70   if (const auto *FD = dyn_cast<FunctionDecl>(D)) {
  71     if (FD->isThisDeclarationADefinition())
  72       if (const Stmt *Body = FD->getBody())
  73         addIfInMain(FD, Body->getBeginLoc());
  74   } else if (const auto *VD = dyn_cast<VarDecl>(D)) {
  75     if (cross_tu::shouldImport(VD, Ctx) && VD->hasInit())
  76       if (const Expr *Init = VD->getInit())
  77         addIfInMain(VD, Init->getBeginLoc());
  78   }
  79
  80   if (const auto *DC = dyn_cast<DeclContext>(D))
  81     for (const Decl *D : DC->decls())
  82       handleDecl(D);
  83 }
  84
  85 void MapExtDefNamesConsumer::addIfInMain(const DeclaratorDecl *DD,
  86                                          SourceLocation defStart) {
  87   std::optional<std::string> LookupName =
  88       CrossTranslationUnitContext::getLookupName(DD);
  89   if (!LookupName)
  90     return;
  91   assert(!LookupName->empty() && "Lookup name should be non-empty.");
  92
  93   if (CurrentFileName.empty()) {
  94     CurrentFileName = std::string(
  95         SM.getFileEntryForID(SM.getMainFileID())->tryGetRealPathName());
  96     if (CurrentFileName.empty())
  97       CurrentFileName = "invalid_file";
  98   }
  99
 100   switch (DD->getLinkageInternal()) {
 101   case Linkage::External:
 102   case Linkage::VisibleNone:
 103   case Linkage::UniqueExternal:
 104     if (SM.isInMainFile(defStart))
 105       Index[*LookupName] = CurrentFileName;
 106     break;
 107   case Linkage::Invalid:
 108     llvm_unreachable("Linkage has not been computed!");
 109   default:
 110     break;
 111   }
 112 }
 113
 114 class MapExtDefNamesAction : public ASTFrontendAction {
 115 protected:
 116   std::unique_ptr<ASTConsumer> CreateASTConsumer(CompilerInstance &CI,
 117                                                  llvm::StringRef) override {
 118     return std::make_unique<MapExtDefNamesConsumer>(CI.getASTContext());
 119   }
 120 };
 121
 122 static cl::extrahelp CommonHelp(CommonOptionsParser::HelpMessage);
 123
 124 static IntrusiveRefCntPtr<DiagnosticsEngine> Diags;
 125
 126 IntrusiveRefCntPtr<DiagnosticsEngine> GetDiagnosticsEngine() {
 127   if (Diags) {
 128     // Call reset to make sure we don't mix errors
 129     Diags->Reset(false);
 130     return Diags;
 131   }
 132
 133   IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts = new DiagnosticOptions();
 134   TextDiagnosticPrinter *DiagClient =
 135       new TextDiagnosticPrinter(llvm::errs(), &*DiagOpts);
 136   DiagClient->setPrefix("clang-extdef-mappping");
 137   IntrusiveRefCntPtr<DiagnosticIDs> DiagID(new DiagnosticIDs());
 138
 139   IntrusiveRefCntPtr<DiagnosticsEngine> DiagEngine(
 140       new DiagnosticsEngine(DiagID, &*DiagOpts, DiagClient));
 141   Diags.swap(DiagEngine);
 142
 143   // Retain this one time so it's not destroyed by ASTUnit::LoadFromASTFile
 144   Diags->Retain();
 145   return Diags;
 146 }
 147
 148 static CompilerInstance *CI = nullptr;
 149
 150 static bool HandleAST(StringRef AstPath) {
 151
 152   if (!CI)
 153     CI = new CompilerInstance();
 154
 155   IntrusiveRefCntPtr<DiagnosticsEngine> DiagEngine = GetDiagnosticsEngine();
 156
 157   std::unique_ptr<ASTUnit> Unit = ASTUnit::LoadFromASTFile(
 158       AstPath, CI->getPCHContainerOperations()->getRawReader(),
 159       ASTUnit::LoadASTOnly, DiagEngine, CI->getFileSystemOpts(),
 160       CI->getHeaderSearchOptsPtr());
 161
 162   if (!Unit)
 163     return false;
 164
 165   FileManager FM(CI->getFileSystemOpts());
 166   SmallString<128> AbsPath(AstPath);
 167   FM.makeAbsolutePath(AbsPath);
 168
 169   MapExtDefNamesConsumer Consumer =
 170       MapExtDefNamesConsumer(Unit->getASTContext(), AbsPath);
 171   Consumer.HandleTranslationUnit(Unit->getASTContext());
 172
 173   return true;
 174 }
 175
 176 static int HandleFiles(ArrayRef<std::string> SourceFiles,
 177                        CompilationDatabase &compilations) {
 178   std::vector<std::string> SourcesToBeParsed;
 179
 180   // Loop over all input files, if they are pre-compiled AST
 181   // process them directly in HandleAST, otherwise put them
 182   // on a list for ClangTool to handle.
 183   for (StringRef Src : SourceFiles) {
 184     if (Src.ends_with(".ast")) {
 185       if (!HandleAST(Src)) {
 186         return 1;
 187       }
 188     } else {
 189       SourcesToBeParsed.push_back(Src.str());
 190     }
 191   }
 192
 193   if (!SourcesToBeParsed.empty()) {
 194     ClangTool Tool(compilations, SourcesToBeParsed);
 195     return Tool.run(newFrontendActionFactory<MapExtDefNamesAction>().get());
 196   }
 197
 198   return 0;
 199 }
 200
 201 int main(int argc, const char **argv) {
 202   // Print a stack trace if we signal out.
 203   sys::PrintStackTraceOnErrorSignal(argv[0], false);
 204   PrettyStackTraceProgram X(argc, argv);
 205
 206   const char *Overview = "\nThis tool collects the USR name and location "
 207                          "of external definitions in the source files "
 208                          "(excluding headers).\n"
 209                          "Input can be either source files that are compiled "
 210                          "with compile database or .ast files that are "
 211                          "created from clang's -emit-ast option.\n";
 212   auto ExpectedParser = CommonOptionsParser::create(
 213       argc, argv, ClangExtDefMapGenCategory, cl::ZeroOrMore, Overview);
 214   if (!ExpectedParser) {
 215     llvm::errs() << ExpectedParser.takeError();
 216     return 1;
 217   }
 218   CommonOptionsParser &OptionsParser = ExpectedParser.get();
 219
 220   llvm::InitializeAllTargetInfos();
 221   llvm::InitializeAllTargetMCs();
 222   llvm::InitializeAllAsmParsers();
 223
 224   return HandleFiles(OptionsParser.getSourcePathList(),
 225                      OptionsParser.getCompilations());
 226 }