[clang] NFCI: Use FileEntryRef in ModuleMapParser

(cherry picked from commit c23d65b)

Author: jansvoboda11

clang/include/clang/Lex/ModuleMap.h

@@ -731,7 +731,7 @@ class ModuleMap {
   ///        that caused us to load this module map file, if any.
   ///
   /// \returns true if an error occurred, false otherwise.
-  bool parseModuleMapFile(const FileEntry *File, bool IsSystem,
+  bool parseModuleMapFile(FileEntryRef File, bool IsSystem,
                           DirectoryEntryRef HomeDir, FileID ID = FileID(),
                           unsigned *Offset = nullptr,
                           SourceLocation ExternModuleLoc = SourceLocation());

clang/lib/Lex/HeaderSearch.cpp

@@ -1663,19 +1663,17 @@ bool HeaderSearch::findUsableModuleForFrameworkHeader(
   return true;
 }
 
-static const FileEntry *getPrivateModuleMap(FileEntryRef File,
-                                            FileManager &FileMgr) {
+static OptionalFileEntryRef getPrivateModuleMap(FileEntryRef File,
+                                                FileManager &FileMgr) {
   StringRef Filename = llvm::sys::path::filename(File.getName());
   SmallString<128>  PrivateFilename(File.getDir().getName());
   if (Filename == "module.map")
     llvm::sys::path::append(PrivateFilename, "module_private.map");
   else if (Filename == "module.modulemap")
     llvm::sys::path::append(PrivateFilename, "module.private.modulemap");
   else
-    return nullptr;
-  if (auto File = FileMgr.getFile(PrivateFilename))
-    return *File;
-  return nullptr;
+    return std::nullopt;
+  return FileMgr.getOptionalFileRef(PrivateFilename);
 }
 
 bool HeaderSearch::loadModuleMapFile(FileEntryRef File, bool IsSystem,
@@ -1741,8 +1739,8 @@ HeaderSearch::loadModuleMapFileImpl(FileEntryRef File, bool IsSystem,
   }
 
   // Try to load a corresponding private module map.
-  if (const FileEntry *PMMFile = getPrivateModuleMap(File, FileMgr)) {
-    if (ModMap.parseModuleMapFile(PMMFile, IsSystem, Dir)) {
+  if (OptionalFileEntryRef PMMFile = getPrivateModuleMap(File, FileMgr)) {
+    if (ModMap.parseModuleMapFile(*PMMFile, IsSystem, Dir)) {
       LoadedModuleMaps[File] = false;
       return LMM_InvalidModuleMap;
     }

clang/lib/Lex/ModuleMap.cpp

@@ -1519,7 +1519,7 @@ namespace clang {
     ModuleMap ⤅
 
     /// The current module map file.
-    const FileEntry *ModuleMapFile;
+    FileEntryRef ModuleMapFile;
 
     /// Source location of most recent parsed module declaration
     SourceLocation CurrModuleDeclLoc;
@@ -1591,7 +1591,7 @@ namespace clang {
   public:
     explicit ModuleMapParser(Lexer &L, SourceManager &SourceMgr,
                              const TargetInfo *Target, DiagnosticsEngine &Diags,
-                             ModuleMap &Map, const FileEntry *ModuleMapFile,
+                             ModuleMap &Map, FileEntryRef ModuleMapFile,
                              DirectoryEntryRef Directory, bool IsSystem)
         : L(L), SourceMgr(SourceMgr), Target(Target), Diags(Diags), Map(Map),
           ModuleMapFile(ModuleMapFile), Directory(Directory),
@@ -2127,7 +2127,7 @@ void ModuleMapParser::parseModuleDecl() {
     ActiveModule->NoUndeclaredIncludes = true;
   ActiveModule->Directory = Directory;
 
-  StringRef MapFileName(ModuleMapFile->getName());
+  StringRef MapFileName(ModuleMapFile.getName());
   if (MapFileName.endswith("module.private.modulemap") ||
       MapFileName.endswith("module_private.map")) {
     ActiveModule->ModuleMapIsPrivate = true;
@@ -3117,7 +3117,7 @@ bool ModuleMapParser::parseModuleMapFile() {
   } while (true);
 }
 
-bool ModuleMap::parseModuleMapFile(const FileEntry *File, bool IsSystem,
+bool ModuleMap::parseModuleMapFile(FileEntryRef File, bool IsSystem,
                                    DirectoryEntryRef Dir, FileID ID,
                                    unsigned *Offset,
                                    SourceLocation ExternModuleLoc) {