Make SourceManager::createFileID(UnownedTag, ...) take a const llvm::MemoryBuffer*

Requires making the llvm::MemoryBuffer* stored by SourceManager const,
which in turn requires making the accessors for that return const
llvm::MemoryBuffer*s and updating all call sites.

The original motivation for this was to use it and fix the TODO in
CodeGenAction.cpp's ConvertBackendLocation() by using the UnownedTag
version of createFileID, and since llvm::SourceMgr* hands out a const
llvm::MemoryBuffer* this is required. I'm not sure if fixing the TODO
this way actually works, but this seems like a good change on its own
anyways.

No intended behavior change.

Differential Revision: https://reviews.llvm.org/D60247

llvm-svn: 357724

10 files changed, 48 insertions, 41 deletions

diff --git a/clang/include/clang/Basic/SourceManager.h b/clang/include/clang/Basic/SourceManager.h
index 2bdf1d5e39f..a9882839958 100644
--- a/clang/include/clang/Basic/SourceManager.h
+++ b/clang/include/clang/Basic/SourceManager.h
@@ -105,7 +105,7 @@ namespace SrcMgr {
     ///
     /// This is owned by the ContentCache object.  The bits indicate
     /// whether the buffer is invalid.
-    mutable llvm::PointerIntPair<llvm::MemoryBuffer *, 2> Buffer;
+    mutable llvm::PointerIntPair<const llvm::MemoryBuffer *, 2> Buffer;
 
   public:
     /// Reference to the file entry representing this ContentCache.
@@ -184,10 +184,10 @@ namespace SrcMgr {
     ///   will be emitted at.
     ///
     /// \param Invalid If non-NULL, will be set \c true if an error occurred.
-    llvm::MemoryBuffer *getBuffer(DiagnosticsEngine &Diag,
-                                  const SourceManager &SM,
-                                  SourceLocation Loc = SourceLocation(),
-                                  bool *Invalid = nullptr) const;
+    const llvm::MemoryBuffer *getBuffer(DiagnosticsEngine &Diag,
+                                        const SourceManager &SM,
+                                        SourceLocation Loc = SourceLocation(),
+                                        bool *Invalid = nullptr) const;
 
     /// Returns the size of the content encapsulated by this
     /// ContentCache.
@@ -209,11 +209,13 @@ namespace SrcMgr {
 
     /// Get the underlying buffer, returning NULL if the buffer is not
     /// yet available.
-    llvm::MemoryBuffer *getRawBuffer() const { return Buffer.getPointer(); }
+    const llvm::MemoryBuffer *getRawBuffer() const {
+      return Buffer.getPointer();
+    }
 
     /// Replace the existing buffer (which will be deleted)
     /// with the given buffer.
-    void replaceBuffer(llvm::MemoryBuffer *B, bool DoNotFree = false);
+    void replaceBuffer(const llvm::MemoryBuffer *B, bool DoNotFree = false);
 
     /// Determine whether the buffer itself is invalid.
     bool isBufferInvalid() const {
@@ -841,7 +843,7 @@ public:
   ///
   /// This does no caching of the buffer and takes ownership of the
   /// MemoryBuffer, so only pass a MemoryBuffer to this once.
-  FileID createFileID(UnownedTag, llvm::MemoryBuffer *Buffer,
+  FileID createFileID(UnownedTag, const llvm::MemoryBuffer *Buffer,
                       SrcMgr::CharacteristicKind FileCharacter = SrcMgr::C_User,
                       int LoadedID = 0, unsigned LoadedOffset = 0,
                       SourceLocation IncludeLoc = SourceLocation()) {
@@ -887,8 +889,8 @@ public:
   ///
   /// \param Invalid If non-NULL, will be set \c true if an error
   /// occurs while retrieving the memory buffer.
-  llvm::MemoryBuffer *getMemoryBufferForFile(const FileEntry *File,
-                                             bool *Invalid = nullptr);
+  const llvm::MemoryBuffer *getMemoryBufferForFile(const FileEntry *File,
+                                                   bool *Invalid = nullptr);
 
   /// Override the contents of the given source file by providing an
   /// already-allocated buffer.
@@ -951,8 +953,8 @@ public:
   ///
   /// If there is an error opening this buffer the first time, this
   /// manufactures a temporary buffer and returns a non-empty error string.
-  llvm::MemoryBuffer *getBuffer(FileID FID, SourceLocation Loc,
-                                bool *Invalid = nullptr) const {
+  const llvm::MemoryBuffer *getBuffer(FileID FID, SourceLocation Loc,
+                                      bool *Invalid = nullptr) const {
     bool MyInvalid = false;
     const SrcMgr::SLocEntry &Entry = getSLocEntry(FID, &MyInvalid);
     if (MyInvalid || !Entry.isFile()) {
@@ -966,7 +968,8 @@ public:
                                                         Invalid);
   }
 
-  llvm::MemoryBuffer *getBuffer(FileID FID, bool *Invalid = nullptr) const {
+  const llvm::MemoryBuffer *getBuffer(FileID FID,
+                                      bool *Invalid = nullptr) const {
     bool MyInvalid = false;
     const SrcMgr::SLocEntry &Entry = getSLocEntry(FID, &MyInvalid);
     if (MyInvalid || !Entry.isFile()) {
@@ -1788,7 +1791,7 @@ private:
 
   /// Create a new ContentCache for the specified  memory buffer.
   const SrcMgr::ContentCache *
-  createMemBufferContentCache(llvm::MemoryBuffer *Buf, bool DoNotFree);
+  createMemBufferContentCache(const llvm::MemoryBuffer *Buf, bool DoNotFree);
 
   FileID getFileIDSlow(unsigned SLocOffset) const;
   FileID getFileIDLocal(unsigned SLocOffset) const;
diff --git a/clang/include/clang/Frontend/FrontendOptions.h b/clang/include/clang/Frontend/FrontendOptions.h
index 8cbba55da4d..645e9ffe81f 100644
--- a/clang/include/clang/Frontend/FrontendOptions.h
+++ b/clang/include/clang/Frontend/FrontendOptions.h
@@ -202,7 +202,7 @@ class FrontendInputFile {
   /// The input, if it comes from a buffer rather than a file. This object
   /// does not own the buffer, and the caller is responsible for ensuring
   /// that it outlives any users.
-  llvm::MemoryBuffer *Buffer = nullptr;
+  const llvm::MemoryBuffer *Buffer = nullptr;
 
   /// The kind of input, e.g., C source, AST file, LLVM IR.
   InputKind Kind;
@@ -214,7 +214,7 @@ public:
   FrontendInputFile() = default;
   FrontendInputFile(StringRef File, InputKind Kind, bool IsSystem = false)
       : File(File.str()), Kind(Kind), IsSystem(IsSystem) {}
-  FrontendInputFile(llvm::MemoryBuffer *Buffer, InputKind Kind,
+  FrontendInputFile(const llvm::MemoryBuffer *Buffer, InputKind Kind,
                     bool IsSystem = false)
       : Buffer(Buffer), Kind(Kind), IsSystem(IsSystem) {}
 
@@ -231,7 +231,7 @@ public:
     return File;
   }
 
-  llvm::MemoryBuffer *getBuffer() const {
+  const llvm::MemoryBuffer *getBuffer() const {
     assert(isBuffer());
     return Buffer;
   }
diff --git a/clang/lib/Basic/SourceManager.cpp b/clang/lib/Basic/SourceManager.cpp
index 57b0bbd1db4..1b139c65523 100644
--- a/clang/lib/Basic/SourceManager.cpp
+++ b/clang/lib/Basic/SourceManager.cpp
@@ -69,7 +69,7 @@ llvm::MemoryBuffer::BufferKind ContentCache::getMemoryBufferKind() const {
   if (!Buffer.getPointer())
     return llvm::MemoryBuffer::MemoryBuffer_Malloc;
 
-  llvm::MemoryBuffer *buf = Buffer.getPointer();
+  const llvm::MemoryBuffer *buf = Buffer.getPointer();
   return buf->getBufferKind();
 }
 
@@ -82,7 +82,7 @@ unsigned ContentCache::getSize() const {
                              : (unsigned) ContentsEntry->getSize();
 }
 
-void ContentCache::replaceBuffer(llvm::MemoryBuffer *B, bool DoNotFree) {
+void ContentCache::replaceBuffer(const llvm::MemoryBuffer *B, bool DoNotFree) {
   if (B && B == Buffer.getPointer()) {
     assert(0 && "Replacing with the same buffer");
     Buffer.setInt(DoNotFree? DoNotFreeFlag : 0);
@@ -95,10 +95,10 @@ void ContentCache::replaceBuffer(llvm::MemoryBuffer *B, bool DoNotFree) {
   Buffer.setInt((B && DoNotFree) ? DoNotFreeFlag : 0);
 }
 
-llvm::MemoryBuffer *ContentCache::getBuffer(DiagnosticsEngine &Diag,
-                                            const SourceManager &SM,
-                                            SourceLocation Loc,
-                                            bool *Invalid) const {
+const llvm::MemoryBuffer *ContentCache::getBuffer(DiagnosticsEngine &Diag,
+                                                  const SourceManager &SM,
+                                                  SourceLocation Loc,
+                                                  bool *Invalid) const {
   // Lazily create the Buffer for ContentCaches that wrap files.  If we already
   // computed it, just return what we have.
   if (Buffer.getPointer() || !ContentsEntry) {
@@ -423,7 +423,7 @@ SourceManager::getOrCreateContentCache(const FileEntry *FileEnt,
 /// Create a new ContentCache for the specified memory buffer.
 /// This does no caching.
 const ContentCache *
-SourceManager::createMemBufferContentCache(llvm::MemoryBuffer *Buffer,
+SourceManager::createMemBufferContentCache(const llvm::MemoryBuffer *Buffer,
                                            bool DoNotFree) {
   // Add a new ContentCache to the MemBufferInfos list and return it.
   ContentCache *Entry = ContentCacheAlloc.Allocate<ContentCache>();
@@ -618,8 +618,8 @@ SourceManager::createExpansionLocImpl(const ExpansionInfo &Info,
   return SourceLocation::getMacroLoc(NextLocalOffset - (TokLength + 1));
 }
 
-llvm::MemoryBuffer *SourceManager::getMemoryBufferForFile(const FileEntry *File,
-                                                          bool *Invalid) {
+const llvm::MemoryBuffer *
+SourceManager::getMemoryBufferForFile(const FileEntry *File, bool *Invalid) {
   const SrcMgr::ContentCache *IR = getOrCreateContentCache(File);
   assert(IR && "getOrCreateContentCache() cannot return NULL");
   return IR->getBuffer(Diag, *this, SourceLocation(), Invalid);
@@ -675,7 +675,7 @@ StringRef SourceManager::getBufferData(FileID FID, bool *Invalid) const {
     return "<<<<<INVALID SOURCE LOCATION>>>>>";
   }
 
-  llvm::MemoryBuffer *Buf = SLoc.getFile().getContentCache()->getBuffer(
+  const llvm::MemoryBuffer *Buf = SLoc.getFile().getContentCache()->getBuffer(
       Diag, *this, SourceLocation(), &MyInvalid);
   if (Invalid)
     *Invalid = MyInvalid;
@@ -1105,8 +1105,9 @@ const char *SourceManager::getCharacterData(SourceLocation SL,
 
     return "<<<<INVALID BUFFER>>>>";
   }
-  llvm::MemoryBuffer *Buffer = Entry.getFile().getContentCache()->getBuffer(
-      Diag, *this, SourceLocation(), &CharDataInvalid);
+  const llvm::MemoryBuffer *Buffer =
+      Entry.getFile().getContentCache()->getBuffer(
+          Diag, *this, SourceLocation(), &CharDataInvalid);
   if (Invalid)
     *Invalid = CharDataInvalid;
   return Buffer->getBufferStart() + (CharDataInvalid? 0 : LocInfo.second);
@@ -1117,7 +1118,7 @@ const char *SourceManager::getCharacterData(SourceLocation SL,
 unsigned SourceManager::getColumnNumber(FileID FID, unsigned FilePos,
                                         bool *Invalid) const {
   bool MyInvalid = false;
-  llvm::MemoryBuffer *MemBuf = getBuffer(FID, &MyInvalid);
+  const llvm::MemoryBuffer *MemBuf = getBuffer(FID, &MyInvalid);
   if (Invalid)
     *Invalid = MyInvalid;
 
@@ -1202,7 +1203,8 @@ static void ComputeLineNumbers(DiagnosticsEngine &Diag, ContentCache *FI,
                                llvm::BumpPtrAllocator &Alloc,
                                const SourceManager &SM, bool &Invalid) {
   // Note that calling 'getBuffer()' may lazily page in the file.
-  MemoryBuffer *Buffer = FI->getBuffer(Diag, SM, SourceLocation(), &Invalid);
+  const MemoryBuffer *Buffer =
+      FI->getBuffer(Diag, SM, SourceLocation(), &Invalid);
   if (Invalid)
     return;
 
@@ -1720,7 +1722,7 @@ SourceLocation SourceManager::translateLineCol(FileID FID,
     return FileLoc.getLocWithOffset(Size);
   }
 
-  llvm::MemoryBuffer *Buffer = Content->getBuffer(Diag, *this);
+  const llvm::MemoryBuffer *Buffer = Content->getBuffer(Diag, *this);
   unsigned FilePos = Content->SourceLineCache[Line - 1];
   const char *Buf = Buffer->getBufferStart() + FilePos;
   unsigned BufLength = Buffer->getBufferSize() - FilePos;
diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
index 46f85a107f6..a982ef89396 100644
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -372,7 +372,7 @@ CGDebugInfo::computeChecksum(FileID FID, SmallString<32> &Checksum) const {
 
   SourceManager &SM = CGM.getContext().getSourceManager();
   bool Invalid;
-  llvm::MemoryBuffer *MemBuffer = SM.getBuffer(FID, &Invalid);
+  const llvm::MemoryBuffer *MemBuffer = SM.getBuffer(FID, &Invalid);
   if (Invalid)
     return None;
 
diff --git a/clang/lib/CodeGen/CodeGenAction.cpp b/clang/lib/CodeGen/CodeGenAction.cpp
index cab3a6bc32b..1f61dc37834 100644
--- a/clang/lib/CodeGen/CodeGenAction.cpp
+++ b/clang/lib/CodeGen/CodeGenAction.cpp
@@ -943,7 +943,8 @@ static void BitcodeInlineAsmDiagHandler(const llvm::SMDiagnostic &SM,
   Diags->Report(DiagID).AddString("cannot compile inline asm");
 }
 
-std::unique_ptr<llvm::Module> CodeGenAction::loadModule(MemoryBufferRef MBRef) {
+std::unique_ptr<llvm::Module>
+CodeGenAction::loadModule(MemoryBufferRef MBRef) {
   CompilerInstance &CI = getCompilerInstance();
   SourceManager &SM = CI.getSourceManager();
 
@@ -1021,7 +1022,7 @@ void CodeGenAction::ExecuteAction() {
     bool Invalid;
     SourceManager &SM = CI.getSourceManager();
     FileID FID = SM.getMainFileID();
-    llvm::MemoryBuffer *MainFile = SM.getBuffer(FID, &Invalid);
+    const llvm::MemoryBuffer *MainFile = SM.getBuffer(FID, &Invalid);
     if (Invalid)
       return;
 
diff --git a/clang/lib/Frontend/PrecompiledPreamble.cpp b/clang/lib/Frontend/PrecompiledPreamble.cpp
index d6418645856..59467c3c41b 100644
--- a/clang/lib/Frontend/PrecompiledPreamble.cpp
+++ b/clang/lib/Frontend/PrecompiledPreamble.cpp
@@ -377,7 +377,7 @@ llvm::ErrorOr<PrecompiledPreamble> PrecompiledPreamble::Build(
           PrecompiledPreamble::PreambleFileHash::createForFile(File->getSize(),
                                                                ModTime);
     } else {
-      llvm::MemoryBuffer *Buffer = SourceMgr.getMemoryBufferForFile(File);
+      const llvm::MemoryBuffer *Buffer = SourceMgr.getMemoryBufferForFile(File);
       FilesInPreamble[File->getName()] =
           PrecompiledPreamble::PreambleFileHash::createForMemoryBuffer(Buffer);
     }
diff --git a/clang/lib/StaticAnalyzer/Checkers/LocalizationChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/LocalizationChecker.cpp
index cb7ba73a091..b67d6095690 100644
--- a/clang/lib/StaticAnalyzer/Checkers/LocalizationChecker.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/LocalizationChecker.cpp
@@ -1140,7 +1140,7 @@ void EmptyLocalizationContextChecker::MethodCrawler::VisitObjCMessageExpr(
   }
 
   bool Invalid = false;
-  llvm::MemoryBuffer *BF =
+  const llvm::MemoryBuffer *BF =
       Mgr.getSourceManager().getBuffer(SLInfo.first, SL, &Invalid);
   if (Invalid)
     return;
diff --git a/clang/lib/StaticAnalyzer/Core/IssueHash.cpp b/clang/lib/StaticAnalyzer/Core/IssueHash.cpp
index 88d9cdab763..e7497f3fbda 100644
--- a/clang/lib/StaticAnalyzer/Core/IssueHash.cpp
+++ b/clang/lib/StaticAnalyzer/Core/IssueHash.cpp
@@ -120,7 +120,7 @@ static std::string GetEnclosingDeclContextSignature(const Decl *D) {
   return "";
 }
 
-static StringRef GetNthLineOfFile(llvm::MemoryBuffer *Buffer, int Line) {
+static StringRef GetNthLineOfFile(const llvm::MemoryBuffer *Buffer, int Line) {
   if (!Buffer)
     return "";
 
@@ -144,7 +144,7 @@ static std::string NormalizeLine(const SourceManager &SM, FullSourceLoc &L,
     col++;
   SourceLocation StartOfLine =
       SM.translateLineCol(SM.getFileID(L), L.getExpansionLineNumber(), col);
-  llvm::MemoryBuffer *Buffer =
+  const llvm::MemoryBuffer *Buffer =
       SM.getBuffer(SM.getFileID(StartOfLine), StartOfLine);
   if (!Buffer)
     return {};
diff --git a/clang/tools/clang-import-test/clang-import-test.cpp b/clang/tools/clang-import-test/clang-import-test.cpp
index 823ebed3ed9..b1078acdda9 100644
--- a/clang/tools/clang-import-test/clang-import-test.cpp
+++ b/clang/tools/clang-import-test/clang-import-test.cpp
@@ -102,7 +102,8 @@ private:
     unsigned LocColumn =
         SM.getSpellingColumnNumber(Loc, /*Invalid=*/nullptr) - 1;
     FileID FID = SM.getFileID(Loc);
-    llvm::MemoryBuffer *Buffer = SM.getBuffer(FID, Loc, /*Invalid=*/nullptr);
+    const llvm::MemoryBuffer *Buffer =
+        SM.getBuffer(FID, Loc, /*Invalid=*/nullptr);
 
     assert(LocData >= Buffer->getBufferStart() &&
            LocData < Buffer->getBufferEnd());
diff --git a/clang/tools/libclang/CIndex.cpp b/clang/tools/libclang/CIndex.cpp
index 1ea85ec30df..7bc1c459d8b 100644
--- a/clang/tools/libclang/CIndex.cpp
+++ b/clang/tools/libclang/CIndex.cpp
@@ -4228,7 +4228,7 @@ const char *clang_getFileContents(CXTranslationUnit TU, CXFile file,
   const SourceManager &SM = cxtu::getASTUnit(TU)->getSourceManager();
   FileID fid = SM.translateFile(static_cast<FileEntry *>(file));
   bool Invalid = true;
-  llvm::MemoryBuffer *buf = SM.getBuffer(fid, &Invalid);
+  const llvm::MemoryBuffer *buf = SM.getBuffer(fid, &Invalid);
   if (Invalid) {
     if (size)
       *size = 0;