[clang] NFC: Add alias for std::pair<FileID, unsigned> used in SourceLocation (#145711)

Introduce a type alias for the commonly used `std::pair<FileID,
unsigned>` to improve code readability, and make it easier for future
updates (64-bit source locations).

Author: hokein

clang/include/clang/Basic/SourceLocation.h

@@ -70,6 +70,8 @@ class FileID {
   int getOpaqueValue() const { return ID; }
 };
 
+using FileIDAndOffset = std::pair<FileID, unsigned>;
+
 /// Encodes a location in the source. The SourceManager can decode this
 /// to get at the full include stack, line and column information.
 ///
@@ -403,7 +405,7 @@ class FullSourceLoc : public SourceLocation {
   /// pair, after walking through all expansion records.
   ///
   /// \see SourceManager::getDecomposedExpansionLoc
-  std::pair<FileID, unsigned> getDecomposedExpansionLoc() const;
+  FileIDAndOffset getDecomposedExpansionLoc() const;
 
   unsigned getSpellingLineNumber(bool *Invalid = nullptr) const;
   unsigned getSpellingColumnNumber(bool *Invalid = nullptr) const;
@@ -424,7 +426,7 @@ class FullSourceLoc : public SourceLocation {
   ///
   /// The first element is the FileID, the second is the offset from the
   /// start of the buffer of the location.
-  std::pair<FileID, unsigned> getDecomposedLoc() const;
+  FileIDAndOffset getDecomposedLoc() const;
 
   bool isInSystemHeader() const;
 

clang/include/clang/Basic/SourceManager.h

@@ -795,7 +795,7 @@ class SourceManager : public RefCountedBase<SourceManager> {
   ///
   /// Used to cache results from and speed-up \c getDecomposedIncludedLoc
   /// function.
-  mutable llvm::DenseMap<FileID, std::pair<FileID, unsigned>> IncludedLocMap;
+  mutable llvm::DenseMap<FileID, FileIDAndOffset> IncludedLocMap;
 
   /// The key value into the IsBeforeInTUCache table.
   using IsBeforeInTUCacheKey = std::pair<FileID, FileID>;
@@ -1269,7 +1269,7 @@ class SourceManager : public RefCountedBase<SourceManager> {
   ///
   /// The first element is the FileID, the second is the offset from the
   /// start of the buffer of the location.
-  std::pair<FileID, unsigned> getDecomposedLoc(SourceLocation Loc) const {
+  FileIDAndOffset getDecomposedLoc(SourceLocation Loc) const {
     FileID FID = getFileID(Loc);
     auto *Entry = getSLocEntryOrNull(FID);
     if (!Entry)
@@ -1281,8 +1281,7 @@ class SourceManager : public RefCountedBase<SourceManager> {
   ///
   /// If the location is an expansion record, walk through it until we find
   /// the final location expanded.
-  std::pair<FileID, unsigned>
-  getDecomposedExpansionLoc(SourceLocation Loc) const {
+  FileIDAndOffset getDecomposedExpansionLoc(SourceLocation Loc) const {
     FileID FID = getFileID(Loc);
     auto *E = getSLocEntryOrNull(FID);
     if (!E)
@@ -1299,8 +1298,7 @@ class SourceManager : public RefCountedBase<SourceManager> {
   ///
   /// If the location is an expansion record, walk through it until we find
   /// its spelling record.
-  std::pair<FileID, unsigned>
-  getDecomposedSpellingLoc(SourceLocation Loc) const {
+  FileIDAndOffset getDecomposedSpellingLoc(SourceLocation Loc) const {
     FileID FID = getFileID(Loc);
     auto *E = getSLocEntryOrNull(FID);
     if (!E)
@@ -1314,7 +1312,7 @@ class SourceManager : public RefCountedBase<SourceManager> {
 
   /// Returns the "included/expanded in" decomposed location of the given
   /// FileID.
-  std::pair<FileID, unsigned> getDecomposedIncludedLoc(FileID FID) const;
+  FileIDAndOffset getDecomposedIncludedLoc(FileID FID) const;
 
   /// Returns the offset from the start of the file that the
   /// specified SourceLocation represents.
@@ -1682,18 +1680,17 @@ class SourceManager : public RefCountedBase<SourceManager> {
   ///          are in the same TU. The second bool is true if the first is true
   ///          and \p LOffs is before \p ROffs.
   std::pair<bool, bool>
-  isInTheSameTranslationUnit(std::pair<FileID, unsigned> &LOffs,
-                             std::pair<FileID, unsigned> &ROffs) const;
+  isInTheSameTranslationUnit(FileIDAndOffset &LOffs,
+                             FileIDAndOffset &ROffs) const;
 
   /// \param Loc a source location in a loaded AST (of a PCH/Module file).
   /// \returns a FileID uniquely identifies the AST of a loaded
   /// module/PCH where `Loc` is at.
   FileID getUniqueLoadedASTFileID(SourceLocation Loc) const;
 
   /// Determines whether the two decomposed source location is in the same TU.
-  bool isInTheSameTranslationUnitImpl(
-      const std::pair<FileID, unsigned> &LOffs,
-      const std::pair<FileID, unsigned> &ROffs) const;
+  bool isInTheSameTranslationUnitImpl(const FileIDAndOffset &LOffs,
+                                      const FileIDAndOffset &ROffs) const;
 
   /// Determines the order of 2 source locations in the "source location
   /// address space".
@@ -1979,11 +1976,10 @@ class SourceManager : public RefCountedBase<SourceManager> {
   SourceLocation getSpellingLocSlowCase(SourceLocation Loc) const;
   SourceLocation getFileLocSlowCase(SourceLocation Loc) const;
 
-  std::pair<FileID, unsigned>
+  FileIDAndOffset
   getDecomposedExpansionLocSlowCase(const SrcMgr::SLocEntry *E) const;
-  std::pair<FileID, unsigned>
-  getDecomposedSpellingLocSlowCase(const SrcMgr::SLocEntry *E,
-                                   unsigned Offset) const;
+  FileIDAndOffset getDecomposedSpellingLocSlowCase(const SrcMgr::SLocEntry *E,
+                                                   unsigned Offset) const;
   void computeMacroArgsCache(MacroArgsMap &MacroArgsCache, FileID FID) const;
   void associateFileChunkWithMacroArgExp(MacroArgsMap &MacroArgsCache,
                                          FileID FID,

clang/lib/AST/ASTContext.cpp

@@ -248,7 +248,7 @@ RawComment *ASTContext::getRawCommentForDeclNoCacheImpl(
 
   // Decompose the location for the declaration and find the beginning of the
   // file buffer.
-  const std::pair<FileID, unsigned> DeclLocDecomp =
+  const FileIDAndOffset DeclLocDecomp =
       SourceMgr.getDecomposedLoc(RepresentativeLocForDecl);
 
   // Slow path.

clang/lib/AST/ASTImporter.cpp

@@ -9989,7 +9989,7 @@ Expected<SourceLocation> ASTImporter::Import(SourceLocation FromLoc) {
   SourceManager &FromSM = FromContext.getSourceManager();
   bool IsBuiltin = FromSM.isWrittenInBuiltinFile(FromLoc);
 
-  std::pair<FileID, unsigned> Decomposed = FromSM.getDecomposedLoc(FromLoc);
+  FileIDAndOffset Decomposed = FromSM.getDecomposedLoc(FromLoc);
   Expected<FileID> ToFileIDOrErr = Import(Decomposed.first, IsBuiltin);
   if (!ToFileIDOrErr)
     return ToFileIDOrErr.takeError();

clang/lib/AST/CommentLexer.cpp

@@ -904,7 +904,7 @@ void Lexer::lex(Token &T) {
 StringRef Lexer::getSpelling(const Token &Tok,
                              const SourceManager &SourceMgr) const {
   SourceLocation Loc = Tok.getLocation();
-  std::pair<FileID, unsigned> LocInfo = SourceMgr.getDecomposedLoc(Loc);
+  FileIDAndOffset LocInfo = SourceMgr.getDecomposedLoc(Loc);
 
   bool InvalidTemp = false;
   StringRef File = SourceMgr.getBufferData(LocInfo.first, &InvalidTemp);

clang/lib/AST/Expr.cpp

@@ -1356,8 +1356,7 @@ StringLiteral::getLocationOfByte(unsigned ByteNo, const SourceManager &SM,
     SourceLocation StrTokSpellingLoc = SM.getSpellingLoc(StrTokLoc);
 
     // Re-lex the token to get its length and original spelling.
-    std::pair<FileID, unsigned> LocInfo =
-        SM.getDecomposedLoc(StrTokSpellingLoc);
+    FileIDAndOffset LocInfo = SM.getDecomposedLoc(StrTokSpellingLoc);
     bool Invalid = false;
     StringRef Buffer = SM.getBufferData(LocInfo.first, &Invalid);
     if (Invalid) {

clang/lib/AST/RawCommentList.cpp

@@ -224,8 +224,8 @@ comments::FullComment *RawComment::parse(const ASTContext &Context,
 static bool onlyWhitespaceBetween(SourceManager &SM,
                                   SourceLocation Loc1, SourceLocation Loc2,
                                   unsigned MaxNewlinesAllowed) {
-  std::pair<FileID, unsigned> Loc1Info = SM.getDecomposedLoc(Loc1);
-  std::pair<FileID, unsigned> Loc2Info = SM.getDecomposedLoc(Loc2);
+  FileIDAndOffset Loc1Info = SM.getDecomposedLoc(Loc1);
+  FileIDAndOffset Loc2Info = SM.getDecomposedLoc(Loc2);
 
   // Question does not make sense if locations are in different files.
   if (Loc1Info.first != Loc2Info.first)
@@ -279,8 +279,7 @@ void RawCommentList::addComment(const RawComment &RC,
   if (RC.isOrdinary() && !CommentOpts.ParseAllComments)
     return;
 
-  std::pair<FileID, unsigned> Loc =
-      SourceMgr.getDecomposedLoc(RC.getBeginLoc());
+  FileIDAndOffset Loc = SourceMgr.getDecomposedLoc(RC.getBeginLoc());
 
   const FileID CommentFile = Loc.first;
   const unsigned CommentOffset = Loc.second;

clang/lib/Analysis/PathDiagnostic.cpp

@@ -323,8 +323,8 @@ static bool compareCrossTUSourceLocs(FullSourceLoc XL, FullSourceLoc YL) {
     return true;
   if (XL.isValid() && YL.isInvalid())
     return false;
-  std::pair<FileID, unsigned> XOffs = XL.getDecomposedLoc();
-  std::pair<FileID, unsigned> YOffs = YL.getDecomposedLoc();
+  FileIDAndOffset XOffs = XL.getDecomposedLoc();
+  FileIDAndOffset YOffs = YL.getDecomposedLoc();
   const SourceManager &SM = XL.getManager();
   std::pair<bool, bool> InSameTU = SM.isInTheSameTranslationUnit(XOffs, YOffs);
   if (InSameTU.first)

clang/lib/Basic/Diagnostic.cpp

@@ -173,7 +173,7 @@ void DiagnosticsEngine::DiagStateMap::append(SourceManager &SrcMgr,
   CurDiagState = State;
   CurDiagStateLoc = Loc;
 
-  std::pair<FileID, unsigned> Decomp = SrcMgr.getDecomposedLoc(Loc);
+  FileIDAndOffset Decomp = SrcMgr.getDecomposedLoc(Loc);
   unsigned Offset = Decomp.second;
   for (File *F = getFile(SrcMgr, Decomp.first); F;
        Offset = F->ParentOffset, F = F->Parent) {
@@ -199,7 +199,7 @@ DiagnosticsEngine::DiagStateMap::lookup(SourceManager &SrcMgr,
   if (Files.empty())
     return FirstDiagState;
 
-  std::pair<FileID, unsigned> Decomp = SrcMgr.getDecomposedLoc(Loc);
+  FileIDAndOffset Decomp = SrcMgr.getDecomposedLoc(Loc);
   const File *F = getFile(SrcMgr, Decomp.first);
   return F->lookup(Decomp.second);
 }
@@ -226,7 +226,7 @@ DiagnosticsEngine::DiagStateMap::getFile(SourceManager &SrcMgr,
   // We created a new File; look up the diagnostic state at the start of it and
   // initialize it.
   if (ID.isValid()) {
-    std::pair<FileID, unsigned> Decomp = SrcMgr.getDecomposedIncludedLoc(ID);
+    FileIDAndOffset Decomp = SrcMgr.getDecomposedIncludedLoc(ID);
     F.Parent = getFile(SrcMgr, Decomp.first);
     F.ParentOffset = Decomp.second;
     F.StateTransitions.push_back({F.Parent->lookup(Decomp.second), 0});
@@ -263,8 +263,7 @@ void DiagnosticsEngine::DiagStateMap::dump(SourceManager &SrcMgr,
                    << ">: " << SrcMgr.getBufferOrFake(ID).getBufferIdentifier();
 
       if (F.second.Parent) {
-        std::pair<FileID, unsigned> Decomp =
-            SrcMgr.getDecomposedIncludedLoc(ID);
+        FileIDAndOffset Decomp = SrcMgr.getDecomposedIncludedLoc(ID);
         assert(File.ParentOffset == Decomp.second);
         llvm::errs() << " parent " << File.Parent << " <FileID "
                      << Decomp.first.getHashValue() << "> ";

clang/lib/Basic/Sarif.cpp

@@ -117,7 +117,7 @@ static unsigned int adjustColumnPos(FullSourceLoc Loc,
                                     unsigned int TokenLen = 0) {
   assert(!Loc.isInvalid() && "invalid Loc when adjusting column position");
 
-  std::pair<FileID, unsigned> LocInfo = Loc.getDecomposedExpansionLoc();
+  FileIDAndOffset LocInfo = Loc.getDecomposedExpansionLoc();
   std::optional<MemoryBufferRef> Buf =
       Loc.getManager().getBufferOrNone(LocInfo.first);
   assert(Buf && "got an invalid buffer for the location's file");