Implement a lexer for structured comments.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@159223 91177308-0d34-0410-b5e6-96231b3b80d8

17 files changed, 2326 insertions, 27 deletions

diff --git a/include/clang-c/Index.h b/include/clang-c/Index.h
index b7bd8bb738..2397ae1925 100644
--- a/include/clang-c/Index.h
+++ b/include/clang-c/Index.h
@@ -3201,6 +3201,12 @@ CINDEX_LINKAGE CXSourceRange clang_Cursor_getCommentRange(CXCursor C);
 CINDEX_LINKAGE CXString clang_Cursor_getRawCommentText(CXCursor C);
 
 /**
+ * \brief Given a cursor that represents a declaration, return the associated
+ * \\brief paragraph; otherwise return the first paragraph.
+ */
+CINDEX_LINKAGE CXString clang_Cursor_getBriefCommentText(CXCursor C);
+
+/**
  * @}
  */
 
diff --git a/include/clang/AST/CommentBriefParser.h b/include/clang/AST/CommentBriefParser.h
new file mode 100644
index 0000000000..e343b94643
--- /dev/null
+++ b/include/clang/AST/CommentBriefParser.h
@@ -0,0 +1,49 @@
+//===--- CommentBriefParser.h - Dumb comment parser -------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file defines a very simple Doxygen comment parser.
+//
+//===----------------------------------------------------------------------===//
+
+
+#ifndef LLVM_CLANG_AST_BRIEF_COMMENT_PARSER_H
+#define LLVM_CLANG_AST_BRIEF_COMMENT_PARSER_H
+
+#include "clang/AST/CommentLexer.h"
+
+namespace clang {
+namespace comments {
+
+/// A very simple comment parser that extracts just the brief description or
+/// first paragraph.
+class BriefParser {
+  Lexer &L;
+
+  /// Current lookahead token.
+  Token Tok;
+
+  SourceLocation ConsumeToken() {
+    SourceLocation Loc = Tok.getLocation();
+    L.lex(Tok);
+    return Loc;
+  }
+
+public:
+  BriefParser(Lexer &L);
+
+  /// Return \\brief paragraph, if it exists; otherwise return the first
+  /// paragraph.
+  std::string Parse();
+};
+
+} // end namespace comments
+} // end namespace clang
+
+#endif
+
diff --git a/include/clang/AST/CommentLexer.h b/include/clang/AST/CommentLexer.h
new file mode 100644
index 0000000000..7f7ae62758
--- /dev/null
+++ b/include/clang/AST/CommentLexer.h
@@ -0,0 +1,352 @@
+//===--- CommentLexer.h - Lexer for structured comments ---------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file defines lexer for structured comments and supporting token class.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_AST_COMMENT_LEXER_H
+#define LLVM_CLANG_AST_COMMENT_LEXER_H
+
+#include "clang/Basic/SourceManager.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/Support/raw_ostream.h"
+
+namespace clang {
+namespace comments {
+
+class Lexer;
+
+namespace tok {
+enum TokenKind {
+  eof,
+  newline,
+  text,
+  command,
+  verbatim_block_begin,
+  verbatim_block_line,
+  verbatim_block_end,
+  verbatim_line,
+  html_tag_open,      // <tag
+  html_ident,         // attr
+  html_equals,        // =
+  html_quoted_string, // "blah\"blah" or 'blah\'blah'
+  html_greater,       // >
+  html_tag_close,     // </tag>
+
+  // Markdown tokens (not supported yet).
+  ruler,
+  md_code_line,   // Line indented at least by 4 spaces.
+  md_code_inline, // `code`
+  md_emph,        // _text_ or *text*
+  md_strong,      // __text__ or *text*
+  md_header       // ### level 3 header ###
+};
+} // end namespace tok
+
+class CommentOptions {
+public:
+  bool Markdown;
+};
+
+/// \brief Comment token.
+class Token {
+  friend class Lexer;
+
+  /// The location of the token.
+  SourceLocation Loc;
+
+  /// The actual kind of the token.
+  tok::TokenKind Kind;
+
+  /// Length of the token spelling in comment.  Can be 0 for synthenized
+  /// tokens.
+  unsigned Length;
+
+  /// Contains text value associated with a token.
+  const char *TextPtr1;
+  unsigned TextLen1;
+
+  /// Contains text value associated with a token.
+  const char *TextPtr2;
+  unsigned TextLen2;
+
+public:
+  SourceLocation getLocation() const LLVM_READONLY { return Loc; }
+  void setLocation(SourceLocation SL) { Loc = SL; }
+
+  tok::TokenKind getKind() const LLVM_READONLY { return Kind; }
+  void setKind(tok::TokenKind K) { Kind = K; }
+
+  bool is(tok::TokenKind K) const LLVM_READONLY { return Kind == K; }
+  bool isNot(tok::TokenKind K) const LLVM_READONLY { return Kind != K; }
+
+  unsigned getLength() const LLVM_READONLY { return Length; }
+  void setLength(unsigned L) { Length = L; }
+
+  StringRef getText() const LLVM_READONLY {
+    assert(is(tok::text));
+    return StringRef(TextPtr1, TextLen1);
+  }
+
+  void setText(StringRef Text) {
+    assert(is(tok::text));
+    TextPtr1 = Text.data();
+    TextLen1 = Text.size();
+  }
+
+  StringRef getCommandName() const LLVM_READONLY {
+    assert(is(tok::command));
+    return StringRef(TextPtr1, TextLen1);
+  }
+
+  void setCommandName(StringRef Name) {
+    assert(is(tok::command));
+    TextPtr1 = Name.data();
+    TextLen1 = Name.size();
+  }
+
+  StringRef getVerbatimBlockName() const LLVM_READONLY {
+    assert(is(tok::verbatim_block_begin) || is(tok::verbatim_block_end));
+    return StringRef(TextPtr1, TextLen1);
+  }
+
+  void setVerbatimBlockName(StringRef Name) {
+    assert(is(tok::verbatim_block_begin) || is(tok::verbatim_block_end));
+    TextPtr1 = Name.data();
+    TextLen1 = Name.size();
+  }
+
+  StringRef getVerbatimBlockText() const LLVM_READONLY {
+    assert(is(tok::verbatim_block_line));
+    return StringRef(TextPtr1, TextLen1);
+  }
+
+  void setVerbatimBlockText(StringRef Text) {
+    assert(is(tok::verbatim_block_line));
+    TextPtr1 = Text.data();
+    TextLen1 = Text.size();
+  }
+
+  /// Returns the name of verbatim line command.
+  StringRef getVerbatimLineName() const LLVM_READONLY {
+    assert(is(tok::verbatim_line));
+    return StringRef(TextPtr1, TextLen1);
+  }
+
+  void setVerbatimLineName(StringRef Name) {
+    assert(is(tok::verbatim_line));
+    TextPtr1 = Name.data();
+    TextLen1 = Name.size();
+  }
+
+  StringRef getVerbatimLineText() const LLVM_READONLY {
+    assert(is(tok::verbatim_line));
+    return StringRef(TextPtr2, TextLen2);
+  }
+
+  void setVerbatimLineText(StringRef Text) {
+    assert(is(tok::verbatim_line));
+    TextPtr2 = Text.data();
+    TextLen2 = Text.size();
+  }
+
+  StringRef getHTMLTagOpenName() const LLVM_READONLY {
+    assert(is(tok::html_tag_open));
+    return StringRef(TextPtr1, TextLen1);
+  }
+
+  void setHTMLTagOpenName(StringRef Name) {
+    assert(is(tok::html_tag_open));
+    TextPtr1 = Name.data();
+    TextLen1 = Name.size();
+  }
+
+  StringRef getHTMLIdent() const LLVM_READONLY {
+    assert(is(tok::html_ident));
+    return StringRef(TextPtr1, TextLen1);
+  }
+
+  void setHTMLIdent(StringRef Name) {
+    assert(is(tok::html_ident));
+    TextPtr1 = Name.data();
+    TextLen1 = Name.size();
+  }
+
+  StringRef getHTMLQuotedString() const LLVM_READONLY {
+    assert(is(tok::html_quoted_string));
+    return StringRef(TextPtr1, TextLen1);
+  }
+
+  void setHTMLQuotedString(StringRef Str) {
+    assert(is(tok::html_quoted_string));
+    TextPtr1 = Str.data();
+    TextLen1 = Str.size();
+  }
+
+  StringRef getHTMLTagCloseName() const LLVM_READONLY {
+    assert(is(tok::html_tag_close));
+    return StringRef(TextPtr1, TextLen1);
+  }
+
+  void setHTMLTagCloseName(StringRef Name) {
+    assert(is(tok::html_tag_close));
+    TextPtr1 = Name.data();
+    TextLen1 = Name.size();
+  }
+
+  void dump(const Lexer &L, const SourceManager &SM) const;
+};
+
+/// \brief Comment lexer.
+class Lexer {
+private:
+  Lexer(const Lexer&);          // DO NOT IMPLEMENT
+  void operator=(const Lexer&); // DO NOT IMPLEMENT
+
+  const char *const BufferStart;
+  const char *const BufferEnd;
+  SourceLocation FileLoc;
+  CommentOptions CommOpts;
+
+  const char *BufferPtr;
+
+  /// One past end pointer for the current comment.  For BCPL comments points
+  /// to newline or BufferEnd, for C comments points to star in '*/'.
+  const char *CommentEnd;
+
+  enum LexerCommentState {
+    LCS_BeforeComment,
+    LCS_InsideBCPLComment,
+    LCS_InsideCComment,
+    LCS_BetweenComments
+  };
+
+  /// Low-level lexer state, track if we are inside or outside of comment.
+  LexerCommentState CommentState;
+
+  enum LexerState {
+    /// Lexing normal comment text
+    LS_Normal,
+
+    /// Finished lexing verbatim block beginning command, will lex first body
+    /// line.
+    LS_VerbatimBlockFirstLine,
+
+    /// Lexing verbatim block body line-by-line, skipping line-starting
+    /// decorations.
+    LS_VerbatimBlockBody,
+
+    /// Finished lexing \verbatim <TAG \endverbatim part, lexing tag attributes.
+    LS_HTMLOpenTag
+  };
+
+  /// Current lexing mode.
+  LexerState State;
+
+  /// A verbatim-like block command eats every character (except line starting
+  /// decorations) until matching end command is seen or comment end is hit.
+  struct VerbatimBlockCommand {
+    StringRef BeginName;
+    StringRef EndName;
+  };
+
+  typedef SmallVector<VerbatimBlockCommand, 4> VerbatimBlockCommandVector;
+
+  /// Registered verbatim-like block commands.
+  VerbatimBlockCommandVector VerbatimBlockCommands;
+
+  /// If State is LS_VerbatimBlock, contains the the name of verbatim end
+  /// command, including command marker.
+  SmallString<16> VerbatimBlockEndCommandName;
+
+  bool isVerbatimBlockCommand(StringRef BeginName, StringRef &EndName) const;
+
+  /// A verbatim-like line command eats everything until a newline is seen or
+  /// comment end is hit.
+  struct VerbatimLineCommand {
+    StringRef Name;
+  };
+
+  typedef SmallVector<VerbatimLineCommand, 4> VerbatimLineCommandVector;
+
+  /// Registered verbatim-like line commands.
+  VerbatimLineCommandVector VerbatimLineCommands;
+
+  bool isVerbatimLineCommand(StringRef Name) const;
+
+  void formTokenWithChars(Token &Result, const char *TokEnd,
+                          tok::TokenKind Kind) {
+    const unsigned TokLen = TokEnd - BufferPtr;
+    Result.setLocation(getSourceLocation(BufferPtr));
+    Result.setKind(Kind);
+    Result.setLength(TokLen);
+#ifndef NDEBUG
+    Result.TextPtr1 = "<UNSET>";
+    Result.TextLen1 = 7;
+    Result.TextPtr2 = "<UNSET>";
+    Result.TextLen2 = 7;
+#endif
+    BufferPtr = TokEnd;
+  }
+
+  SourceLocation getSourceLocation(const char *Loc) const {
+    assert(Loc >= BufferStart && Loc <= BufferEnd &&
+           "Location out of range for this buffer!");
+
+    const unsigned CharNo = Loc - BufferStart;
+    return FileLoc.getLocWithOffset(CharNo);
+  }
+
+  /// Eat string matching regexp \code \s*\* \endcode.
+  void skipLineStartingDecorations();
+
+  /// Lex stuff inside comments.  CommentEnd should be set correctly.
+  void lexCommentText(Token &T);
+
+  void setupAndLexVerbatimBlock(Token &T,
+                                const char *TextBegin,
+                                char Marker, StringRef EndName);
+
+  void lexVerbatimBlockFirstLine(Token &T);
+
+  void lexVerbatimBlockBody(Token &T);
+
+  void lexVerbatimLine(Token &T, const char *TextBegin);
+
+  void setupAndLexHTMLOpenTag(Token &T);
+
+  void lexHTMLOpenTag(Token &T);
+
+  void lexHTMLCloseTag(Token &T);
+
+public:
+  Lexer(SourceLocation FileLoc, const CommentOptions &CommOpts,
+        const char *BufferStart, const char *BufferEnd);
+
+  void lex(Token &T);
+
+  StringRef getSpelling(const Token &Tok,
+                        const SourceManager &SourceMgr,
+                        bool *Invalid = NULL) const;
+
+  /// \brief Register a new verbatim block command.
+  void addVerbatimBlockCommand(StringRef BeginName, StringRef EndName);
+
+  /// \brief Register a new verbatim line command.
+  void addVerbatimLineCommand(StringRef Name);
+};
+
+} // end namespace comments
+} // end namespace clang
+
+#endif
+
diff --git a/include/clang/AST/RawCommentList.h b/include/clang/AST/RawCommentList.h
index 0965cb3a62..d670fd1428 100644
--- a/include/clang/AST/RawCommentList.h
+++ b/include/clang/AST/RawCommentList.h
@@ -15,6 +15,7 @@
 
 namespace clang {
 
+class ASTContext;
 class ASTReader;
 
 class RawComment {
@@ -27,7 +28,7 @@ public:
     CK_BCPLExcl,     ///< \code //! stuff \endcode
     CK_JavaDoc,      ///< \code /** stuff */ \endcode
     CK_Qt,           ///< \code /*! stuff */ \endcode, also used by HeaderDoc
-    CK_Merged        ///< Two or more Doxygen comments merged together
+    CK_Merged        ///< Two or more documentation comments merged together
   };
 
   RawComment() : Kind(CK_Invalid), IsAlmostTrailingComment(false) { }
@@ -53,7 +54,7 @@ public:
   /// \code /**< stuff */ \endcode
   /// \code /*!< stuff */ \endcode
   bool isTrailingComment() const LLVM_READONLY {
-    assert(isDoxygen());
+    assert(isDocumentation());
     return IsTrailingComment;
   }
 
@@ -64,13 +65,13 @@ public:
     return IsAlmostTrailingComment;
   }
 
-  /// Returns true if this comment is not a Doxygen comment.
+  /// Returns true if this comment is not a documentation comment.
   bool isOrdinary() const LLVM_READONLY {
     return (Kind == CK_OrdinaryBCPL) || (Kind == CK_OrdinaryC);
   }
 
-  /// Returns true if this comment any kind of a Doxygen comment.
-  bool isDoxygen() const LLVM_READONLY {
+  /// Returns true if this comment any kind of a documentation comment.
+  bool isDocumentation() const LLVM_READONLY {
     return !isInvalid() && !isOrdinary();
   }
 
@@ -91,11 +92,21 @@ public:
   unsigned getBeginLine(const SourceManager &SM) const;
   unsigned getEndLine(const SourceManager &SM) const;
 
+  StringRef getBriefText(const ASTContext &Context) const {
+    if (BriefTextValid)
+      return BriefText;
+
+    return extractBriefText(Context);
+  }
+
 private:
   SourceRange Range;
 
   mutable StringRef RawText;
-  mutable bool RawTextValid : 1; ///< True if RawText is valid
+  mutable StringRef BriefText;
+
+  mutable bool RawTextValid : 1;   ///< True if RawText is valid
+  mutable bool BriefTextValid : 1; ///< True if BriefText is valid
 
   unsigned Kind : 3;
 
@@ -118,6 +129,8 @@ private:
 
   StringRef getRawTextSlow(const SourceManager &SourceMgr) const;
 
+  StringRef extractBriefText(const ASTContext &Context) const;
+
   friend class ASTReader;
 };
 
diff --git a/lib/AST/ASTContext.cpp b/lib/AST/ASTContext.cpp
index 23751a56f2..ca631736d9 100644
--- a/lib/AST/ASTContext.cpp
+++ b/lib/AST/ASTContext.cpp
@@ -90,7 +90,7 @@ const RawComment *ASTContext::getRawCommentForDeclNoCache(const Decl *D) const {
 
   // First check whether we have a trailing comment.
   if (Comment != RawComments.end() &&
-      Comment->isDoxygen() && Comment->isTrailingComment() &&
+      Comment->isDocumentation() && Comment->isTrailingComment() &&
       !isa<TagDecl>(D) && !isa<NamespaceDecl>(D)) {
     std::pair<FileID, unsigned> CommentBeginDecomp
       = SourceMgr.getDecomposedLoc(Comment->getSourceRange().getBegin());
@@ -111,7 +111,7 @@ const RawComment *ASTContext::getRawCommentForDeclNoCache(const Decl *D) const {
   --Comment;
 
   // Check that we actually have a non-member Doxygen comment.
-  if (!Comment->isDoxygen() || Comment->isTrailingComment())
+  if (!Comment->isDocumentation() || Comment->isTrailingComment())
     return NULL;
 
   // Decompose the end of the comment.
diff --git a/lib/AST/CMakeLists.txt b/lib/AST/CMakeLists.txt
index d8605367a7..5dad60c490 100644
--- a/lib/AST/CMakeLists.txt
+++ b/lib/AST/CMakeLists.txt
@@ -8,6 +8,8 @@ add_clang_library(clangAST
   ASTImporter.cpp
   AttrImpl.cpp
   CXXInheritance.cpp
+  CommentBriefParser.cpp
+  CommentLexer.cpp
   Decl.cpp
   DeclarationName.cpp
   DeclBase.cpp
diff --git a/lib/AST/CommentBriefParser.cpp b/lib/AST/CommentBriefParser.cpp
new file mode 100644
index 0000000000..528fd2606f
--- /dev/null
+++ b/lib/AST/CommentBriefParser.cpp
@@ -0,0 +1,76 @@
+//===--- CommentBriefParser.cpp - Dumb comment parser ---------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/AST/CommentBriefParser.h"
+
+namespace clang {
+namespace comments {
+
+std::string BriefParser::Parse() {
+  std::string FirstParagraph;
+  std::string Brief;
+  bool InFirstParagraph = true;
+  bool InBrief = false;
+  bool BriefDone = false;
+
+  while (Tok.isNot(tok::eof)) {
+    if (Tok.is(tok::text)) {
+      if (InFirstParagraph)
+        FirstParagraph += Tok.getText();
+      if (InBrief)
+        Brief += Tok.getText();
+      ConsumeToken();
+      continue;
+    }
+
+    if (!BriefDone && Tok.is(tok::command) && Tok.getCommandName() == "brief") {
+      InBrief = true;
+      ConsumeToken();
+      continue;
+    }
+
+    if (Tok.is(tok::newline)) {
+      if (InFirstParagraph)
+        FirstParagraph += '\n';
+      if (InBrief)
+        Brief += '\n';
+      ConsumeToken();
+
+      if (Tok.is(tok::newline)) {
+        ConsumeToken();
+        // We found a paragraph end.
+        InFirstParagraph = false;
+        if (InBrief) {
+          InBrief = false;
+          BriefDone = true;
+        }
+      }
+      continue;
+    }
+
+    // We didn't handle this token, so just drop it.
+    ConsumeToken();
+  }
+
+  if (Brief.size() > 0)
+    return Brief;
+
+  return FirstParagraph;
+}
+
+BriefParser::BriefParser(Lexer &L) : L(L)
+{
+  // Get lookahead token.
+  ConsumeToken();
+}
+
+} // end namespace comments
+} // end namespace clang
+
+
diff --git a/lib/AST/CommentLexer.cpp b/lib/AST/CommentLexer.cpp
new file mode 100644
index 0000000000..e5529dad15
--- /dev/null
+++ b/lib/AST/CommentLexer.cpp
@@ -0,0 +1,676 @@
+#include "clang/AST/CommentLexer.h"
+#include "llvm/ADT/StringSwitch.h"
+#include "llvm/Support/ErrorHandling.h"
+
+namespace clang {
+namespace comments {
+
+void Token::dump(const Lexer &L, const SourceManager &SM) const {
+  llvm::errs() << "comments::Token Kind=" << Kind << " ";
+  Loc.dump(SM);
+  llvm::errs() << " " << Length << " \"" << L.getSpelling(*this, SM) << "\"\n";
+}
+
+bool Lexer::isVerbatimBlockCommand(StringRef BeginName,
+                                  StringRef &EndName) const {
+  const char *Result = llvm::StringSwitch<const char *>(BeginName)
+    .Case("code", "endcode")
+    .Case("verbatim", "endverbatim")
+    .Case("htmlonly", "endhtmlonly")
+    .Case("latexonly", "endlatexonly")
+    .Case("xmlonly", "endxmlonly")
+    .Case("manonly", "endmanonly")
+    .Case("rtfonly", "endrtfonly")
+
+    .Case("dot", "enddot")
+    .Case("msc", "endmsc")
+
+    .Case("f$", "f$") // Inline LaTeX formula
+    .Case("f[", "f]") // Displayed LaTeX formula
+    .Case("f{", "f}") // LaTeX environment
+
+    .Default(NULL);
+
+  if (Result) {
+    EndName = Result;
+    return true;
+  }
+
+  for (VerbatimBlockCommandVector::const_iterator
+           I = VerbatimBlockCommands.begin(),
+           E = VerbatimBlockCommands.end();
+       I != E; ++I)
+    if (I->BeginName == BeginName) {
+      EndName = I->EndName;
+      return true;
+    }
+
+  return false;
+}
+
+bool Lexer::isVerbatimLineCommand(StringRef Name) const {
+  bool Result = llvm::StringSwitch<bool>(Name)
+  .Case("fn", true)
+  .Case("var", true)
+  .Case("property", true)
+  .Case("typedef", true)
+
+  .Case("overload", true)
+
+  .Case("defgroup", true)
+  .Case("ingroup", true)
+  .Case("addtogroup", true)
+  .Case("weakgroup", true)
+  .Case("name", true)
+
+  .Case("section", true)
+  .Case("subsection", true)
+  .Case("subsubsection", true)
+  .Case("paragraph", true)
+
+  .Case("mainpage", true)
+  .Case("subpage", true)
+  .Case("ref", true)
+
+  .Default(false);
+
+  if (Result)
+    return true;
+
+  for (VerbatimLineCommandVector::const_iterator
+           I = VerbatimLineCommands.begin(),
+           E = VerbatimLineCommands.end();
+       I != E; ++I)
+    if (I->Name == Name)
+      return true;
+
+  return false;
+}
+
+void Lexer::skipLineStartingDecorations() {
+  // This function should be called only for C comments
+  assert(CommentState == LCS_InsideCComment);
+
+  if (BufferPtr == CommentEnd)
+    return;
+
+  switch (*BufferPtr) {
+  case ' ':
+  case '\t':
+  case '\f':
+  case '\v': {
+    const char *NewBufferPtr = BufferPtr;
+    NewBufferPtr++;
+    if (NewBufferPtr == CommentEnd)
+      return;
+
+    char C = *NewBufferPtr;
+    while (C == ' ' || C == '\t' || C == '\f' || C == '\v') {
+      NewBufferPtr++;
+      if (NewBufferPtr == CommentEnd)
+        return;
+      C = *NewBufferPtr;
+    }
+    if (C == '*')
+      BufferPtr = NewBufferPtr + 1;
+    break;
+  }
+  case '*':
+    BufferPtr++;
+    break;
+  }
+}
+
+namespace {
+const char *findNewline(const char *BufferPtr, const char *BufferEnd) {
+  for ( ; BufferPtr != BufferEnd; ++BufferPtr) {
+    const char C = *BufferPtr;
+    if (C == '\n' || C == '\r')
+      return BufferPtr;
+  }
+  return BufferEnd;
+}
+
+const char *skipNewline(const char *BufferPtr, const char *BufferEnd) {
+  if (BufferPtr == BufferEnd)
+    return BufferPtr;
+
+  if (*BufferPtr == '\n')
+    BufferPtr++;
+  else {
+    assert(*BufferPtr == '\r');
+    BufferPtr++;
+    if (BufferPtr != BufferEnd && *BufferPtr == '\n')
+      BufferPtr++;
+  }
+  return BufferPtr;
+}
+
+bool isHTMLIdentifierCharacter(char C) {
+  return (C >= 'a' && C <= 'z') ||
+         (C >= 'A' && C <= 'Z') ||
+         (C >= '0' && C <= '9');
+}
+
+const char *skipHTMLIdentifier(const char *BufferPtr, const char *BufferEnd) {
+  for ( ; BufferPtr != BufferEnd; ++BufferPtr) {
+    if (!isHTMLIdentifierCharacter(*BufferPtr))
+      return BufferPtr;
+  }
+  return BufferEnd;
+}
+
+/// Skip HTML string quoted in single or double quotes.  Escaping quotes inside
+/// string allowed.
+///
+/// Returns pointer to closing quote.
+const char *skipHTMLQuotedString(const char *BufferPtr, const char *BufferEnd)
+{
+  const char Quote = *BufferPtr;
+  assert(Quote == '\"' || Quote == '\'');
+
+  BufferPtr++;
+  for ( ; BufferPtr != BufferEnd; ++BufferPtr) {
+    const char C = *BufferPtr;
+    if (C == Quote && BufferPtr[-1] != '\\')
+      return BufferPtr;
+  }
+  return BufferEnd;
+}
+
+bool isHorizontalWhitespace(char C) {
+  return C == ' ' || C == '\t' || C == '\f' || C == '\v';
+}
+
+bool isWhitespace(char C) {
+  return C == ' ' || C == '\n' || C == '\r' ||
+         C == '\t' || C == '\f' || C == '\v';
+}
+
+const char *skipWhitespace(const char *BufferPtr, const char *BufferEnd) {
+  for ( ; BufferPtr != BufferEnd; ++BufferPtr) {
+    if (!isWhitespace(*BufferPtr))
+      return BufferPtr;
+  }
+  return BufferEnd;
+}
+
+bool isCommandNameCharacter(char C) {
+  return (C >= 'a' && C <= 'z') ||
+         (C >= 'A' && C <= 'Z') ||
+         (C >= '0' && C <= '9');
+}
+
+const char *skipCommandName(const char *BufferPtr, const char *BufferEnd) {
+  for ( ; BufferPtr != BufferEnd; ++BufferPtr) {
+    if (!isCommandNameCharacter(*BufferPtr))
+      return BufferPtr;
+  }
+  return BufferEnd;
+}
+
+/// Return the one past end pointer for BCPL comments.
+/// Handles newlines escaped with backslash or trigraph for backslahs.
+const char *findBCPLCommentEnd(const char *BufferPtr, const char *BufferEnd) {
+  const char *CurPtr = BufferPtr;
+  while (CurPtr != BufferEnd) {
+    char C = *CurPtr;
+    while (C != '\n' && C != '\r') {
+      CurPtr++;
+      if (CurPtr == BufferEnd)
+        return BufferEnd;
+      C = *CurPtr;
+    }
+    // We found a newline, check if it is escaped.
+    const char *EscapePtr = CurPtr - 1;
+    while(isHorizontalWhitespace(*EscapePtr))
+      EscapePtr--;
+
+    if (*EscapePtr == '\\' ||
+        (EscapePtr - 2 >= BufferPtr && EscapePtr[0] == '/' &&
+         EscapePtr[-1] == '?' && EscapePtr[-2] == '?')) {
+      // We found an escaped newline.
+      CurPtr = skipNewline(CurPtr, BufferEnd);
+    } else
+      return CurPtr; // Not an escaped newline.
+  }
+  return BufferEnd;
+}
+
+/// Return the one past end pointer for C comments.
+/// Very dumb, does not handle escaped newlines or trigraphs.
+const char *findCCommentEnd(const char *BufferPtr, const char *BufferEnd) {
+  for ( ; BufferPtr != BufferEnd; ++BufferPtr) {
+    if (*BufferPtr == '*') {
+      assert(BufferPtr + 1 != BufferEnd);
+      if (*(BufferPtr + 1) == '/')
+        return BufferPtr;
+    }
+  }
+  llvm_unreachable("buffer end hit before '*/' was seen");
+}
+} // unnamed namespace
+
+void Lexer::lexCommentText(Token &T) {
+  assert(CommentState == LCS_InsideBCPLComment ||
+         CommentState == LCS_InsideCComment);
+
+  switch (State) {
+  case LS_Normal:
+    break;
+  case LS_VerbatimBlockFirstLine:
+    lexVerbatimBlockFirstLine(T);
+    return;
+  case LS_VerbatimBlockBody:
+    lexVerbatimBlockBody(T);
+    return;
+  case LS_HTMLOpenTag:
+    lexHTMLOpenTag(T);
+    return;
+  }
+
+  assert(State == LS_Normal);
+
+  const char *TokenPtr = BufferPtr;
+  assert(TokenPtr < CommentEnd);
+  while (TokenPtr != CommentEnd) {
+    switch(*TokenPtr) {
+      case '\\':
+      case '@': {
+        TokenPtr++;
+        if (TokenPtr == CommentEnd) {
+          formTokenWithChars(T, TokenPtr, tok::text);
+          T.setText(StringRef(BufferPtr - T.getLength(), T.getLength()));
+          return;
+        }
+        char C = *TokenPtr;
+        switch (C) {
+        default:
+          break;
+
+        case '\\': case '@': case '&': case '$':
+        case '#':  case '<': case '>': case '%':
+        case '\"': case '.': case ':':
+          // This is one of \\ \@ \& \$ etc escape sequences.
+          TokenPtr++;
+          if (C == ':' && TokenPtr != CommentEnd && *TokenPtr == ':') {
+            // This is the \:: escape sequence.
+            TokenPtr++;
+          }
+          formTokenWithChars(T, TokenPtr, tok::text);
+          T.setText(StringRef(BufferPtr - (T.getLength() - 1),
+                              T.getLength() - 1));
+          return;
+        }
+
+        // Don't make zero-length commands.
+        if (!isCommandNameCharacter(*TokenPtr)) {
+          formTokenWithChars(T, TokenPtr, tok::text);
+          T.setText(StringRef(BufferPtr - T.getLength(), T.getLength()));
+          return;
+        }
+
+        TokenPtr = skipCommandName(TokenPtr, CommentEnd);
+        unsigned Length = TokenPtr - (BufferPtr + 1);
+
+        // Hardcoded support for lexing LaTeX formula commands
+        // \f$ \f[ \f] \f{ \f} as a single command.
+        if (Length == 1 && TokenPtr[-1] == 'f' && TokenPtr != CommentEnd) {
+          C = *TokenPtr;
+          if (C == '$' || C == '[' || C == ']' || C == '{' || C == '}') {
+            TokenPtr++;
+            Length++;
+          }
+        }
+
+        const StringRef CommandName(BufferPtr + 1, Length);
+        StringRef EndName;
+
+        if (isVerbatimBlockCommand(CommandName, EndName)) {
+          setupAndLexVerbatimBlock(T, TokenPtr, *BufferPtr, EndName);
+          return;
+        }
+        if (isVerbatimLineCommand(CommandName)) {
+          lexVerbatimLine(T, TokenPtr);
+          return;
+        }
+        formTokenWithChars(T, TokenPtr, tok::command);
+        T.setCommandName(CommandName);
+        return;
+      }
+
+      case '<': {
+        TokenPtr++;
+        if (TokenPtr == CommentEnd) {
+          formTokenWithChars(T, TokenPtr, tok::text);
+          T.setText(StringRef(BufferPtr - T.getLength(), T.getLength()));
+          return;
+        }
+        const char C = *TokenPtr;
+        if (isHTMLIdentifierCharacter(C))
+          setupAndLexHTMLOpenTag(T);
+        else if (C == '/')
+          lexHTMLCloseTag(T);
+        return;
+      }
+
+      case '\n':
+      case '\r':
+        TokenPtr = skipNewline(TokenPtr, CommentEnd);
+        formTokenWithChars(T, TokenPtr, tok::newline);
+
+        if (CommentState == LCS_InsideCComment)
+          skipLineStartingDecorations();
+        return;
+
+      default: {
+        while (true) {
+          TokenPtr++;
+          if (TokenPtr == CommentEnd)
+            break;
+          char C = *TokenPtr;
+          if(C == '\n' || C == '\r' ||
+             C == '\\' || C == '@' || C == '<')
+            break;
+        }
+        formTokenWithChars(T, TokenPtr, tok::text);
+        T.setText(StringRef(BufferPtr - T.getLength(), T.getLength()));
+        return;
+      }
+    }
+  }
+}
+
+void Lexer::setupAndLexVerbatimBlock(Token &T,
+                                     const char *TextBegin,
+                                     char Marker, StringRef EndName) {
+  VerbatimBlockEndCommandName.clear();
+  VerbatimBlockEndCommandName.append(Marker == '\\' ? "\\" : "@");
+  VerbatimBlockEndCommandName.append(EndName);
+
+  formTokenWithChars(T, TextBegin, tok::verbatim_block_begin);
+  T.setVerbatimBlockName(StringRef(TextBegin - (T.getLength() - 1),
+                                   T.getLength() - 1));
+
+  State = LS_VerbatimBlockFirstLine;
+}
+
+void Lexer::lexVerbatimBlockFirstLine(Token &T) {
+  assert(BufferPtr < CommentEnd);
+
+  // FIXME: It would be better to scan the text once, finding either the block
+  // end command or newline.
+  //
+  // Extract current line.
+  const char *Newline = findNewline(BufferPtr, CommentEnd);
+  StringRef Line(BufferPtr, Newline - BufferPtr);
+
+  // Look for end command in current line.
+  size_t Pos = Line.find(VerbatimBlockEndCommandName);
+  const char *NextLine;
+  if (Pos == StringRef::npos) {
+    // Current line is completely verbatim.
+    NextLine = skipNewline(Newline, CommentEnd);
+  } else if (Pos == 0) {
+    // Current line contains just an end command.
+    const char *End = BufferPtr + VerbatimBlockEndCommandName.size();
+    formTokenWithChars(T, End, tok::verbatim_block_end);
+    T.setVerbatimBlockName(StringRef(End - (T.getLength() - 1),
+                                     T.getLength() - 1));
+    State = LS_Normal;
+    return;
+  } else {
+    // There is some text, followed by end command.  Extract text first.
+    NextLine = BufferPtr + Pos;
+  }
+
+  formTokenWithChars(T, NextLine, tok::verbatim_block_line);
+  T.setVerbatimBlockText(StringRef(NextLine - T.getLength(), T.getLength()));
+
+  State = LS_VerbatimBlockBody;
+}
+
+void Lexer::lexVerbatimBlockBody(Token &T) {
+  assert(State == LS_VerbatimBlockBody);
+
+  if (CommentState == LCS_InsideCComment)
+    skipLineStartingDecorations();
+
+  lexVerbatimBlockFirstLine(T);
+}
+
+void Lexer::lexVerbatimLine(Token &T, const char *TextBegin) {
+  // Extract current line.
+  const char *Newline = findNewline(BufferPtr, CommentEnd);
+
+  const StringRef Name(BufferPtr + 1, TextBegin - BufferPtr - 1);
+  const StringRef Text(TextBegin, Newline - TextBegin);
+
+  formTokenWithChars(T, Newline, tok::verbatim_line);
+  T.setVerbatimLineName(Name);
+  T.setVerbatimLineText(Text);
+}
+
+void Lexer::setupAndLexHTMLOpenTag(Token &T) {
+  assert(BufferPtr[0] == '<' && isHTMLIdentifierCharacter(BufferPtr[1]));
+  const char *TagNameEnd = skipHTMLIdentifier(BufferPtr + 2, CommentEnd);
+
+  formTokenWithChars(T, TagNameEnd, tok::html_tag_open);
+  T.setHTMLTagOpenName(StringRef(TagNameEnd - (T.getLength() - 1),
+                                 T.getLength() - 1));
+
+  BufferPtr = skipWhitespace(BufferPtr, CommentEnd);
+
+  if (BufferPtr != CommentEnd && *BufferPtr == '>') {
+    BufferPtr++;
+    return;
+  }
+
+  if (BufferPtr != CommentEnd && isHTMLIdentifierCharacter(*BufferPtr))
+    State = LS_HTMLOpenTag;
+}
+
+void Lexer::lexHTMLOpenTag(Token &T) {
+  assert(State == LS_HTMLOpenTag);
+
+  const char *TokenPtr = BufferPtr;
+  char C = *TokenPtr;
+  if (isHTMLIdentifierCharacter(C)) {
+    TokenPtr = skipHTMLIdentifier(TokenPtr, CommentEnd);
+    formTokenWithChars(T, TokenPtr, tok::html_ident);
+    T.setHTMLIdent(StringRef(TokenPtr - T.getLength(), T.getLength()));
+  } else {
+    switch (C) {
+    case '=':
+      TokenPtr++;
+      formTokenWithChars(T, TokenPtr, tok::html_equals);
+      break;
+    case '\"':
+    case '\'': {
+      const char *OpenQuote = TokenPtr;
+      TokenPtr = skipHTMLQuotedString(TokenPtr, CommentEnd);
+      const char *ClosingQuote = TokenPtr;
+      if (TokenPtr != CommentEnd) // Skip closing quote.
+        TokenPtr++;
+      formTokenWithChars(T, TokenPtr, tok::html_quoted_string);
+      T.setHTMLQuotedString(StringRef(OpenQuote + 1,
+                                      ClosingQuote - (OpenQuote + 1)));
+      break;
+    }
+    case '>':
+      TokenPtr++;
+      formTokenWithChars(T, TokenPtr, tok::html_greater);
+      break;
+    }
+  }
+
+  // Now look ahead and return to normal state if we don't see any HTML tokens
+  // ahead.
+  BufferPtr = skipWhitespace(BufferPtr, CommentEnd);
+  if (BufferPtr == CommentEnd) {
+    State = LS_Normal;
+    return;
+  }
+
+  C = *BufferPtr;
+  if (!isHTMLIdentifierCharacter(C) &&
+      C != '=' && C != '\"' && C != '\'' && C != '>') {
+    State = LS_Normal;
+    return;
+  }
+}
+
+void Lexer::lexHTMLCloseTag(Token &T) {
+  assert(BufferPtr[0] == '<' && BufferPtr[1] == '/');
+
+  const char *TagNameBegin = skipWhitespace(BufferPtr + 2, CommentEnd);
+  const char *TagNameEnd = skipHTMLIdentifier(TagNameBegin, CommentEnd);
+
+  const char *End = skipWhitespace(TagNameEnd, CommentEnd);
+  if (End != CommentEnd && *End == '>')
+    End++;
+
+  formTokenWithChars(T, End, tok::html_tag_close);
+  T.setHTMLTagCloseName(StringRef(TagNameBegin, TagNameEnd - TagNameBegin));
+}
+
+Lexer::Lexer(SourceLocation FileLoc, const CommentOptions &CommOpts,
+             const char *BufferStart, const char *BufferEnd):
+    BufferStart(BufferStart), BufferEnd(BufferEnd),
+    FileLoc(FileLoc), CommOpts(CommOpts), BufferPtr(BufferStart),
+    CommentState(LCS_BeforeComment), State(LS_Normal) {
+}
+
+void Lexer::lex(Token &T) {
+again:
+  switch (CommentState) {
+  case LCS_BeforeComment:
+    if (BufferPtr == BufferEnd) {
+      formTokenWithChars(T, BufferPtr, tok::eof);
+      return;
+    }
+
+    assert(*BufferPtr == '/');
+    BufferPtr++; // Skip first slash.
+    switch(*BufferPtr) {
+    case '/': { // BCPL comment.
+      BufferPtr++; // Skip second slash.
+
+      if (BufferPtr != BufferEnd) {
+        // Skip Doxygen magic marker, if it is present.
+        // It might be missing because of a typo //< or /*<, or because we
+        // merged this non-Doxygen comment into a bunch of Doxygen comments
+        // around it: /** ... */ /* ... */ /** ... */
+        const char C = *BufferPtr;
+        if (C == '/' || C == '!')
+          BufferPtr++;
+      }
+
+      // Skip less-than symbol that marks trailing comments.
+      // Skip it even if the comment is not a Doxygen one, because //< and /*<
+      // are frequent typos.
+      if (BufferPtr != BufferEnd && *BufferPtr == '<')
+        BufferPtr++;
+
+      CommentState = LCS_InsideBCPLComment;
+      State = LS_Normal;
+      CommentEnd = findBCPLCommentEnd(BufferPtr, BufferEnd);
+      goto again;
+    }
+    case '*': { // C comment.
+      BufferPtr++; // Skip star.
+
+      // Skip Doxygen magic marker.
+      const char C = *BufferPtr;
+      if ((C == '*' && *(BufferPtr + 1) != '/') || C == '!')
+        BufferPtr++;
+
+      // Skip less-than symbol that marks trailing comments.
+      if (BufferPtr != BufferEnd && *BufferPtr == '<')
+        BufferPtr++;
+
+      CommentState = LCS_InsideCComment;
+      State = LS_Normal;
+      CommentEnd = findCCommentEnd(BufferPtr, BufferEnd);
+      goto again;
+    }
+    default:
+      llvm_unreachable("second character of comment should be '/' or '*'");
+    }
+
+  case LCS_BetweenComments: {
+    // Consecutive comments are extracted only if there is only whitespace
+    // between them.  So we can search for the start of the next comment.
+    const char *EndWhitespace = BufferPtr;
+    while(EndWhitespace != BufferEnd && *EndWhitespace != '/')
+      EndWhitespace++;
+
+    // Turn any whitespace between comments (and there is only whitespace
+    // between them) into a newline.  We have two newlines between comments
+    // in total (first one was synthesized after a comment).
+    formTokenWithChars(T, EndWhitespace, tok::newline);
+
+    CommentState = LCS_BeforeComment;
+    break;
+  }
+
+  case LCS_InsideBCPLComment:
+  case LCS_InsideCComment:
+    if (BufferPtr != CommentEnd) {
+      lexCommentText(T);
+      break;
+    } else {
+      // Skip C comment closing sequence.
+      if (CommentState == LCS_InsideCComment) {
+        assert(BufferPtr[0] == '*' && BufferPtr[1] == '/');
+        BufferPtr += 2;
+        assert(BufferPtr <= BufferEnd);
+
+        // Synthenize newline just after the C comment, regardless if there is
+        // actually a newline.
+        formTokenWithChars(T, BufferPtr, tok::newline);
+
+        CommentState = LCS_BetweenComments;
+        break;
+      } else {
+        // Don't synthesized a newline after BCPL comment.
+        CommentState = LCS_BetweenComments;
+        goto again;
+      }
+    }
+  }
+}
+
+StringRef Lexer::getSpelling(const Token &Tok,
+                             const SourceManager &SourceMgr,
+                             bool *Invalid) const {
+  SourceLocation Loc = Tok.getLocation();
+  std::pair<FileID, unsigned> LocInfo = SourceMgr.getDecomposedLoc(Loc);
+
+  bool InvalidTemp = false;
+  StringRef File = SourceMgr.getBufferData(LocInfo.first, &InvalidTemp);
+  if (InvalidTemp) {
+    *Invalid = true;
+    return StringRef();
+  }
+
+  const char *Begin = File.data() + LocInfo.second;
+  return StringRef(Begin, Tok.getLength());
+}
+
+void Lexer::addVerbatimBlockCommand(StringRef BeginName, StringRef EndName) {
+  VerbatimBlockCommand VBC;
+  VBC.BeginName = BeginName;
+  VBC.EndName = EndName;
+  VerbatimBlockCommands.push_back(VBC);
+}
+
+void Lexer::addVerbatimLineCommand(StringRef Name) {
+  VerbatimLineCommand VLC;
+  VLC.Name = Name;
+  VerbatimLineCommands.push_back(VLC);
+}
+
+} // end namespace comments
+} // end namespace clang
+
diff --git a/lib/AST/RawCommentList.cpp b/lib/AST/RawCommentList.cpp
index 438fdcd24c..ede47664d6 100644
--- a/lib/AST/RawCommentList.cpp
+++ b/lib/AST/RawCommentList.cpp
@@ -8,6 +8,9 @@
 //===----------------------------------------------------------------------===//
 
 #include "clang/AST/RawCommentList.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/AST/CommentLexer.h"
+#include "clang/AST/CommentBriefParser.h"
 #include "llvm/ADT/STLExtras.h"
 
 using namespace clang;
@@ -126,6 +129,24 @@ StringRef RawComment::getRawTextSlow(const SourceManager &SourceMgr) const {
   return StringRef(BufferStart + BeginOffset, Length);
 }
 
+StringRef RawComment::extractBriefText(const ASTContext &Context) const {
+  // Make sure that RawText is valid.
+  getRawText(Context.getSourceManager());
+
+  comments::Lexer L(Range.getBegin(), comments::CommentOptions(),
+                    RawText.begin(), RawText.end());
+  comments::BriefParser P(L);
+
+  const std::string Result = P.Parse();
+  const unsigned BriefTextLength = Result.size();
+  char *BriefTextPtr = new (Context) char[BriefTextLength + 1];
+  memcpy(BriefTextPtr, Result.c_str(), BriefTextLength + 1);
+  BriefText = StringRef(BriefTextPtr, BriefTextLength);
+  BriefTextValid = true;
+
+  return BriefText;
+}
+
 namespace {
 bool containsOnlyWhitespace(StringRef Str) {
   return Str.find_first_not_of(" \t\f\v\r\n") == StringRef::npos;
diff --git a/test/Index/annotate-comments.cpp b/test/Index/annotate-comments.cpp
index 634f481139..64d1c983bc 100644
--- a/test/Index/annotate-comments.cpp
+++ b/test/Index/annotate-comments.cpp
@@ -163,6 +163,37 @@ class test42 {
   int isdoxy42; /* NOT_DOXYGEN */ ///< isdoxy42 IS_DOXYGEN_SINGLE
 };
 
+/// IS_DOXYGEN_START
+/// It is fine to have a command at the end of comment.
+///\brief
+///
+/// Some malformed command.
+/* \*/
+/**
+ * \brief Aaa aaaaaaa aaaa.
+ * IS_DOXYGEN_END
+ */
+void isdoxy43(void);
+
+/// IS_DOXYGEN_START Aaa bbb
+/// ccc.
+///
+/// Ddd eee.
+/// Fff.
+///
+/// Ggg. IS_DOXYGEN_END
+void isdoxy44(void);
+
+/// IS_DOXYGEN_START Aaa bbb
+/// ccc.
+///
+/// \brief
+/// Ddd eee.
+/// Fff.
+///
+/// Ggg. IS_DOXYGEN_END
+void isdoxy45(void);
+
 #endif
 
 // RUN: rm -rf %t
@@ -187,8 +218,8 @@ class test42 {
 // WRONG-NOT: IS_DOXYGEN_NOT_ATTACHED
 
 // Ensure we don't pick up extra comments.
-// WRONG-NOT: IS_DOXYGEN_START{{.*}}IS_DOXYGEN_START
-// WRONG-NOT: IS_DOXYGEN_END{{.*}}IS_DOXYGEN_END
+// WRONG-NOT: IS_DOXYGEN_START{{.*}}IS_DOXYGEN_START{{.*}}BriefComment=
+// WRONG-NOT: IS_DOXYGEN_END{{.*}}IS_DOXYGEN_END{{.*}}BriefComment=
 
 // RUN: FileCheck %s < %t/out.c-index-direct
 // RUN: FileCheck %s < %t/out.c-index-pch
@@ -226,4 +257,8 @@ class test42 {
 // CHECK: annotate-comments.cpp:155:6: FunctionDecl=isdoxy40:{{.*}} isdoxy40 IS_DOXYGEN_SINGLE
 // CHECK: annotate-comments.cpp:160:5: FunctionDecl=isdoxy41:{{.*}} isdoxy41 IS_DOXYGEN_SINGLE
 // CHECK: annotate-comments.cpp:163:7: FieldDecl=isdoxy42:{{.*}} isdoxy42 IS_DOXYGEN_SINGLE
+// CHECK: annotate-comments.cpp:176:6: FunctionDecl=isdoxy43:{{.*}} IS_DOXYGEN_START{{.*}} IS_DOXYGEN_END
+
+// CHECK: annotate-comments.cpp:185:6: FunctionDecl=isdoxy44:{{.*}} BriefComment=[ IS_DOXYGEN_START Aaa bbb\n ccc.\n]
+// CHECK: annotate-comments.cpp:195:6: FunctionDecl=isdoxy45:{{.*}} BriefComment=[\n Ddd eee.\n Fff.\n]
 
diff --git a/tools/c-index-test/c-index-test.c b/tools/c-index-test/c-index-test.c
index 4c9723da01..73e3e589ce 100644
--- a/tools/c-index-test/c-index-test.c
+++ b/tools/c-index-test/c-index-test.c
@@ -162,6 +162,24 @@ int parse_remapped_files(int argc, const char **argv, int start_arg,
 /* Pretty-printing.                                                           */
 /******************************************************************************/
 
+static void PrintCString(const char *Prefix, const char *CStr) {
+  printf(" %s=[", Prefix);
+  if (CStr != NULL && CStr[0] != '\0') {
+    for ( ; *CStr; ++CStr) {
+      const char C = *CStr;
+      switch (C) {
+        case '\n': printf("\\n"); break;
+        case '\r': printf("\\r"); break;
+        case '\t': printf("\\t"); break;
+        case '\v': printf("\\v"); break;
+        case '\f': printf("\\f"); break;
+        default:   putchar(C);    break;
+      }
+    }
+  }
+  printf("]");
+}
+
 static void PrintRange(CXSourceRange R, const char *str) {
   CXFile begin_file, end_file;
   unsigned begin_line, begin_column, end_line, end_column;
@@ -218,8 +236,10 @@ static void PrintCursor(CXCursor Cursor) {
     CXPlatformAvailability PlatformAvailability[2];
     int NumPlatformAvailability;
     int I;
-    CXString Comment;
-    const char *CommentCString;
+    CXString RawComment;
+    const char *RawCommentCString;
+    CXString BriefComment;
+    const char *BriefCommentCString;
 
     ks = clang_getCursorKindSpelling(Cursor.kind);
     string = want_display_name? clang_getCursorDisplayName(Cursor) 
@@ -401,21 +421,19 @@ static void PrintCursor(CXCursor Cursor) {
         PrintRange(RefNameRange, "RefName");
     }
 
-    Comment = clang_Cursor_getRawCommentText(Cursor);
-    CommentCString = clang_getCString(Comment);
-    if (CommentCString != NULL && CommentCString[0] != '\0') {
-      printf(" Comment=[");
-      for ( ; *CommentCString; ++CommentCString) {
-        if (*CommentCString != '\n')
-          putchar(*CommentCString);
-        else
-          printf("\\n");
-      }
-      printf("]");
-
-      PrintRange(clang_Cursor_getCommentRange(Cursor), "CommentRange");
+    RawComment = clang_Cursor_getRawCommentText(Cursor);
+    RawCommentCString = clang_getCString(RawComment);
+    if (RawCommentCString != NULL && RawCommentCString[0] != '\0') {
+      PrintCString("RawComment", RawCommentCString);
+      PrintRange(clang_Cursor_getCommentRange(Cursor), "RawCommentRange");
+
+      BriefComment = clang_Cursor_getBriefCommentText(Cursor);
+      BriefCommentCString = clang_getCString(BriefComment);
+      if (BriefCommentCString != NULL && BriefCommentCString[0] != '\0')
+        PrintCString("BriefComment", BriefCommentCString);
+      clang_disposeString(BriefComment);
     }
-    clang_disposeString(Comment);
+    clang_disposeString(RawComment);
   }
 }
 
diff --git a/tools/libclang/CIndex.cpp b/tools/libclang/CIndex.cpp
index df8adb419e..250e9e7b2d 100644
--- a/tools/libclang/CIndex.cpp
+++ b/tools/libclang/CIndex.cpp
@@ -5707,6 +5707,24 @@ CXString clang_Cursor_getRawCommentText(CXCursor C) {
 
 } // end: extern "C"
 
+CXString clang_Cursor_getBriefCommentText(CXCursor C) {
+  if (!clang_isDeclaration(C.kind))
+    return createCXString((const char *) NULL);
+
+  const Decl *D = getCursorDecl(C);
+  const ASTContext &Context = getCursorContext(C);
+  const RawComment *RC = Context.getRawCommentForDecl(D);
+
+  if (RC && RC->isDocumentation()) {
+    StringRef BriefText = RC->getBriefText(Context);
+
+    // Don't duplicate the string because RawComment ensures that this memory
+    // will not go away.
+    return createCXString(BriefText, false);
+  }
+
+  return createCXString((const char *) NULL);
+}
 
 //===----------------------------------------------------------------------===//
 // C++ AST instrospection.
diff --git a/tools/libclang/libclang.exports b/tools/libclang/libclang.exports
index d24960b297..c28b3b4083 100644
--- a/tools/libclang/libclang.exports
+++ b/tools/libclang/libclang.exports
@@ -5,6 +5,7 @@ clang_CXIndex_setGlobalOptions
 clang_CXXMethod_isStatic
 clang_CXXMethod_isVirtual
 clang_Cursor_getArgument
+clang_Cursor_getBriefCommentText
 clang_Cursor_getCommentRange
 clang_Cursor_getRawCommentText
 clang_Cursor_getNumArguments
diff --git a/unittests/AST/CMakeLists.txt b/unittests/AST/CMakeLists.txt
new file mode 100644
index 0000000000..738e760419
--- /dev/null
+++ b/unittests/AST/CMakeLists.txt
@@ -0,0 +1,7 @@
+add_clang_unittest(ASTTests
+  CommentLexer.cpp
+  )
+
+target_link_libraries(ASTTests
+  clangAST
+  )
diff --git a/unittests/AST/CommentLexer.cpp b/unittests/AST/CommentLexer.cpp
new file mode 100644
index 0000000000..b73d16ca00
--- /dev/null
+++ b/unittests/AST/CommentLexer.cpp
@@ -0,0 +1,1010 @@
+//===- unittests/AST/CommentLexer.cpp ------ Comment lexer tests ----------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Basic/SourceManager.h"
+#include "clang/Basic/FileManager.h"
+#include "clang/Basic/Diagnostic.h"
+#include "clang/AST/CommentLexer.h"
+#include "llvm/ADT/STLExtras.h"
+#include <vector>
+
+#include "gtest/gtest.h"
+
+using namespace llvm;
+using namespace clang;
+
+namespace clang {
+namespace comments {
+
+namespace {
+class CommentLexerTest : public ::testing::Test {
+protected:
+  CommentLexerTest()
+    : FileMgr(FileMgrOpts),
+      DiagID(new DiagnosticIDs()),
+      Diags(DiagID, new IgnoringDiagConsumer()),
+      SourceMgr(Diags, FileMgr) {
+  }
+
+  FileSystemOptions FileMgrOpts;
+  FileManager FileMgr;
+  IntrusiveRefCntPtr<DiagnosticIDs> DiagID;
+  DiagnosticsEngine Diags;
+  SourceManager SourceMgr;
+
+  void lexString(const char *Source, std::vector<Token> &Toks);
+};
+
+void CommentLexerTest::lexString(const char *Source,
+                                 std::vector<Token> &Toks) {
+  MemoryBuffer *Buf = MemoryBuffer::getMemBuffer(Source);
+  FileID File = SourceMgr.createFileIDForMemBuffer(Buf);
+  SourceLocation Begin = SourceMgr.getLocForStartOfFile(File);
+
+  comments::Lexer L(Begin, CommentOptions(),
+                    Source, Source + strlen(Source));
+
+  while (1) {
+    Token Tok;
+    L.lex(Tok);
+    if (Tok.is(tok::eof))
+      break;
+    Toks.push_back(Tok);
+  }
+}
+
+} // unnamed namespace
+
+// Empty source range should be handled.
+TEST_F(CommentLexerTest, Basic1) {
+  const char *Source = "";
+  std::vector<Token> Toks;
+
+  lexString(Source, Toks);
+
+  ASSERT_EQ(0U, Toks.size());
+}
+
+// Empty comments should be handled.
+TEST_F(CommentLexerTest, Basic2) {
+  const char *Sources[] = {
+    "//", "///", "//!", "///<", "//!<"
+  };
+  for (size_t i = 0, e = array_lengthof(Sources); i != e; i++) {
+    std::vector<Token> Toks;
+
+    lexString(Sources[i], Toks);
+
+    ASSERT_EQ(1U, Toks.size());
+
+    ASSERT_EQ(tok::newline, Toks[0].getKind());
+  }
+}
+
+// Empty comments should be handled.
+TEST_F(CommentLexerTest, Basic3) {
+  const char *Sources[] = {
+    "/**/", "/***/", "/*!*/", "/**<*/", "/*!<*/"
+  };
+  for (size_t i = 0, e = array_lengthof(Sources); i != e; i++) {
+    std::vector<Token> Toks;
+
+    lexString(Sources[i], Toks);
+
+    ASSERT_EQ(2U, Toks.size());
+
+    ASSERT_EQ(tok::newline, Toks[0].getKind());
+    ASSERT_EQ(tok::newline, Toks[1].getKind());
+  }
+}
+
+// Single comment with plain text.
+TEST_F(CommentLexerTest, Basic4) {
+  const char *Sources[] = {
+    "// Meow",   "/// Meow",    "//! Meow",
+    "// Meow\n", "// Meow\r\n", "//! Meow\r",
+  };
+
+  for (size_t i = 0, e = array_lengthof(Sources); i != e; i++) {
+    std::vector<Token> Toks;
+
+    lexString(Sources[i], Toks);
+
+    ASSERT_EQ(2U, Toks.size());
+
+    ASSERT_EQ(tok::text,          Toks[0].getKind());
+    ASSERT_EQ(StringRef(" Meow"), Toks[0].getText());
+
+    ASSERT_EQ(tok::newline,       Toks[1].getKind());
+  }
+}
+
+// Single comment with plain text.
+TEST_F(CommentLexerTest, Basic5) {
+  const char *Sources[] = {
+    "/* Meow*/", "/** Meow*/",  "/*! Meow*/"
+  };
+
+  for (size_t i = 0, e = array_lengthof(Sources); i != e; i++) {
+    std::vector<Token> Toks;
+
+    lexString(Sources[i], Toks);
+
+    ASSERT_EQ(3U, Toks.size());
+
+    ASSERT_EQ(tok::text,          Toks[0].getKind());
+    ASSERT_EQ(StringRef(" Meow"), Toks[0].getText());
+
+    ASSERT_EQ(tok::newline,       Toks[1].getKind());
+    ASSERT_EQ(tok::newline,       Toks[2].getKind());
+  }
+}
+
+// Test newline escaping.
+TEST_F(CommentLexerTest, Basic6) {
+  const char *Sources[] = {
+    "// Aaa\\\n"   " Bbb\\ \n"   " Ccc?" "?/\n",
+    "// Aaa\\\r\n" " Bbb\\ \r\n" " Ccc?" "?/\r\n",
+    "// Aaa\\\r"   " Bbb\\ \r"   " Ccc?" "?/\r"
+  };
+
+  for (size_t i = 0, e = array_lengthof(Sources); i != e; i++) {
+    std::vector<Token> Toks;
+
+    lexString(Sources[i], Toks);
+
+    ASSERT_EQ(10U, Toks.size());
+
+    ASSERT_EQ(tok::text,         Toks[0].getKind());
+    ASSERT_EQ(StringRef(" Aaa"), Toks[0].getText());
+    ASSERT_EQ(tok::text,         Toks[1].getKind());
+    ASSERT_EQ(StringRef("\\"),   Toks[1].getText());
+    ASSERT_EQ(tok::newline,      Toks[2].getKind());
+
+    ASSERT_EQ(tok::text,         Toks[3].getKind());
+    ASSERT_EQ(StringRef(" Bbb"), Toks[3].getText());
+    ASSERT_EQ(tok::text,         Toks[4].getKind());
+    ASSERT_EQ(StringRef("\\"),   Toks[4].getText());
+    ASSERT_EQ(tok::text,         Toks[5].getKind());
+    ASSERT_EQ(StringRef(" "),    Toks[5].getText());
+    ASSERT_EQ(tok::newline,      Toks[6].getKind());
+
+    ASSERT_EQ(tok::text,         Toks[7].getKind());
+    ASSERT_EQ(StringRef(" Ccc?" "?/"), Toks[7].getText());
+    ASSERT_EQ(tok::newline,      Toks[8].getKind());
+
+    ASSERT_EQ(tok::newline,      Toks[9].getKind());
+  }
+}
+
+// Check that we skip C-style aligned stars correctly.
+TEST_F(CommentLexerTest, Basic7) {
+  const char *Source =
+    "/* Aaa\n"
+    " * Bbb\r\n"
+    "\t* Ccc\n"
+    "  ! Ddd\n"
+    "  * Eee\n"
+    "  ** Fff\n"
+    " */";
+  std::vector<Token> Toks;
+
+  lexString(Source, Toks);
+
+  ASSERT_EQ(15U, Toks.size());
+
+  ASSERT_EQ(tok::text,         Toks[0].getKind());
+  ASSERT_EQ(StringRef(" Aaa"), Toks[0].getText());
+  ASSERT_EQ(tok::newline,      Toks[1].getKind());
+
+  ASSERT_EQ(tok::text,         Toks[2].getKind());
+  ASSERT_EQ(StringRef(" Bbb"), Toks[2].getText());
+  ASSERT_EQ(tok::newline,      Toks[3].getKind());
+
+  ASSERT_EQ(tok::text,         Toks[4].getKind());
+  ASSERT_EQ(StringRef(" Ccc"), Toks[4].getText());
+  ASSERT_EQ(tok::newline,      Toks[5].getKind());
+
+  ASSERT_EQ(tok::text,            Toks[6].getKind());
+  ASSERT_EQ(StringRef("  ! Ddd"), Toks[6].getText());
+  ASSERT_EQ(tok::newline,         Toks[7].getKind());
+
+  ASSERT_EQ(tok::text,         Toks[8].getKind());
+  ASSERT_EQ(StringRef(" Eee"), Toks[8].getText());
+  ASSERT_EQ(tok::newline,      Toks[9].getKind());
+
+  ASSERT_EQ(tok::text,          Toks[10].getKind());
+  ASSERT_EQ(StringRef("* Fff"), Toks[10].getText());
+  ASSERT_EQ(tok::newline,       Toks[11].getKind());
+
+  ASSERT_EQ(tok::text,         Toks[12].getKind());
+  ASSERT_EQ(StringRef(" "),    Toks[12].getText());
+
+  ASSERT_EQ(tok::newline,      Toks[13].getKind());
+  ASSERT_EQ(tok::newline,      Toks[14].getKind());
+}
+
+// A command marker followed by comment end.
+TEST_F(CommentLexerTest, DoxygenCommand1) {
+  const char *Sources[] = { "//@", "///@", "//!@" };
+  for (size_t i = 0, e = array_lengthof(Sources); i != e; i++) {
+    std::vector<Token> Toks;
+
+    lexString(Sources[i], Toks);
+
+    ASSERT_EQ(2U, Toks.size());
+
+    ASSERT_EQ(tok::text,          Toks[0].getKind());
+    ASSERT_EQ(StringRef("@"),     Toks[0].getText());
+
+    ASSERT_EQ(tok::newline,       Toks[1].getKind());
+  }
+}
+
+// A command marker followed by comment end.
+TEST_F(CommentLexerTest, DoxygenCommand2) {
+  const char *Sources[] = { "/*@*/", "/**@*/", "/*!@*/"};
+  for (size_t i = 0, e = array_lengthof(Sources); i != e; i++) {
+    std::vector<Token> Toks;
+
+    lexString(Sources[i], Toks);
+
+    ASSERT_EQ(3U, Toks.size());
+
+    ASSERT_EQ(tok::text,          Toks[0].getKind());
+    ASSERT_EQ(StringRef("@"),     Toks[0].getText());
+
+    ASSERT_EQ(tok::newline,       Toks[1].getKind());
+    ASSERT_EQ(tok::newline,       Toks[2].getKind());
+  }
+}
+
+// A command marker followed by comment end.
+TEST_F(CommentLexerTest, DoxygenCommand3) {
+  const char *Sources[] = { "/*\\*/", "/**\\*/" };
+  for (size_t i = 0, e = array_lengthof(Sources); i != e; i++) {
+    std::vector<Token> Toks;
+
+    lexString(Sources[i], Toks);
+
+    ASSERT_EQ(3U, Toks.size());
+
+    ASSERT_EQ(tok::text,           Toks[0].getKind());
+    ASSERT_EQ(StringRef("\\"),     Toks[0].getText());
+
+    ASSERT_EQ(tok::newline,        Toks[1].getKind());
+    ASSERT_EQ(tok::newline,        Toks[2].getKind());
+  }
+}
+
+// Doxygen escape sequences.
+TEST_F(CommentLexerTest, DoxygenCommand4) {
+  const char *Source =
+    "/// \\\\ \\@ \\& \\$ \\# \\< \\> \\% \\\" \\. \\::";
+  const char *Text[] = {
+    " ",
+    "\\", " ", "@", " ", "&", " ", "$",  " ", "#", " ",
+    "<",  " ", ">", " ", "%", " ", "\"", " ", ".", " ",
+    "::", ""
+  };
+
+  std::vector<Token> Toks;
+
+  lexString(Source, Toks);
+
+  ASSERT_EQ(array_lengthof(Text), Toks.size());
+
+  for (size_t i = 0, e = Toks.size(); i != e; i++) {
+    if(Toks[i].is(tok::text))
+      ASSERT_EQ(StringRef(Text[i]), Toks[i].getText())
+        << "index " << i;
+  }
+}
+
+TEST_F(CommentLexerTest, DoxygenCommand5) {
+  const char *Source = "/// \\brief Aaa.";
+  std::vector<Token> Toks;
+
+  lexString(Source, Toks);
+
+  ASSERT_EQ(4U, Toks.size());
+
+  ASSERT_EQ(tok::text,          Toks[0].getKind());
+  ASSERT_EQ(StringRef(" "),     Toks[0].getText());
+
+  ASSERT_EQ(tok::command,       Toks[1].getKind());
+  ASSERT_EQ(StringRef("brief"), Toks[1].getCommandName());
+
+  ASSERT_EQ(tok::text,          Toks[2].getKind());
+  ASSERT_EQ(StringRef(" Aaa."), Toks[2].getText());
+
+  ASSERT_EQ(tok::newline,       Toks[3].getKind());
+}
+
+TEST_F(CommentLexerTest, DoxygenCommand6) {
+  const char *Source = "/// \\aaa\\bbb \\ccc\t\\ddd\n";
+  std::vector<Token> Toks;
+
+  lexString(Source, Toks);
+
+  ASSERT_EQ(8U, Toks.size());
+
+  ASSERT_EQ(tok::text,        Toks[0].getKind());
+  ASSERT_EQ(StringRef(" "),   Toks[0].getText());
+
+  ASSERT_EQ(tok::command,     Toks[1].getKind());
+  ASSERT_EQ(StringRef("aaa"), Toks[1].getCommandName());
+
+  ASSERT_EQ(tok::command,     Toks[2].getKind());
+  ASSERT_EQ(StringRef("bbb"), Toks[2].getCommandName());
+
+  ASSERT_EQ(tok::text,        Toks[3].getKind());
+  ASSERT_EQ(StringRef(" "),   Toks[3].getText());
+
+  ASSERT_EQ(tok::command,     Toks[4].getKind());
+  ASSERT_EQ(StringRef("ccc"), Toks[4].getCommandName());
+
+  ASSERT_EQ(tok::text,        Toks[5].getKind());
+  ASSERT_EQ(StringRef("\t"),  Toks[5].getText());
+
+  ASSERT_EQ(tok::command,     Toks[6].getKind());
+  ASSERT_EQ(StringRef("ddd"), Toks[6].getCommandName());
+
+  ASSERT_EQ(tok::newline,     Toks[7].getKind());
+}
+
+// Empty verbatim block.
+TEST_F(CommentLexerTest, VerbatimBlock1) {
+  const char *Sources[] = {
+    "/// \\verbatim\\endverbatim\n//",
+    "/** \\verbatim\\endverbatim*/"
+  };
+
+  for (size_t i = 0, e = array_lengthof(Sources); i != e; i++) {
+    std::vector<Token> Toks;
+
+    lexString(Sources[i], Toks);
+
+    ASSERT_EQ(5U, Toks.size());
+
+    ASSERT_EQ(tok::text,                 Toks[0].getKind());
+    ASSERT_EQ(StringRef(" "),            Toks[0].getText());
+
+    ASSERT_EQ(tok::verbatim_block_begin, Toks[1].getKind());
+    ASSERT_EQ(StringRef("verbatim"),     Toks[1].getVerbatimBlockName());
+
+    ASSERT_EQ(tok::verbatim_block_end,   Toks[2].getKind());
+    ASSERT_EQ(StringRef("endverbatim"),  Toks[2].getVerbatimBlockName());
+
+    ASSERT_EQ(tok::newline,              Toks[3].getKind());
+    ASSERT_EQ(tok::newline,              Toks[4].getKind());
+  }
+}
+
+// Empty verbatim block without an end command.
+TEST_F(CommentLexerTest, VerbatimBlock2) {
+  const char *Sources[] = {
+    "/// \\verbatim\n//",
+    "/** \\verbatim*/"
+  };
+
+  for (size_t i = 0, e = array_lengthof(Sources); i != e; i++) {
+    std::vector<Token> Toks;
+
+    lexString(Sources[i], Toks);
+
+    ASSERT_EQ(4U, Toks.size());
+
+    ASSERT_EQ(tok::text,                 Toks[0].getKind());
+    ASSERT_EQ(StringRef(" "),            Toks[0].getText());
+
+    ASSERT_EQ(tok::verbatim_block_begin, Toks[1].getKind());
+    ASSERT_EQ(StringRef("verbatim"),     Toks[1].getVerbatimBlockName());
+
+    ASSERT_EQ(tok::newline,              Toks[2].getKind());
+    ASSERT_EQ(tok::newline,              Toks[3].getKind());
+  }
+}
+
+// Single-line verbatim block.
+TEST_F(CommentLexerTest, VerbatimBlock3) {
+  const char *Sources[] = {
+    "/// Meow \\verbatim aaa \\endverbatim\n//",
+    "/** Meow \\verbatim aaa \\endverbatim*/"
+  };
+
+  for (size_t i = 0, e = array_lengthof(Sources); i != e; i++) {
+    std::vector<Token> Toks;
+
+    lexString(Sources[i], Toks);
+
+    ASSERT_EQ(6U, Toks.size());
+
+    ASSERT_EQ(tok::text,                 Toks[0].getKind());
+    ASSERT_EQ(StringRef(" Meow "),       Toks[0].getText());
+
+    ASSERT_EQ(tok::verbatim_block_begin, Toks[1].getKind());
+    ASSERT_EQ(StringRef("verbatim"),     Toks[1].getVerbatimBlockName());
+
+    ASSERT_EQ(tok::verbatim_block_line,  Toks[2].getKind());
+    ASSERT_EQ(StringRef(" aaa "),        Toks[2].getVerbatimBlockText());
+
+    ASSERT_EQ(tok::verbatim_block_end,   Toks[3].getKind());
+    ASSERT_EQ(StringRef("endverbatim"),  Toks[3].getVerbatimBlockName());
+
+    ASSERT_EQ(tok::newline,              Toks[4].getKind());
+    ASSERT_EQ(tok::newline,              Toks[5].getKind());
+  }
+}
+
+// Single-line verbatim block without an end command.
+TEST_F(CommentLexerTest, VerbatimBlock4) {
+  const char *Sources[] = {
+    "/// Meow \\verbatim aaa \n//",
+    "/** Meow \\verbatim aaa */"
+  };
+
+  for (size_t i = 0, e = array_lengthof(Sources); i != e; i++) {
+    std::vector<Token> Toks;
+
+    lexString(Sources[i], Toks);
+
+    ASSERT_EQ(5U, Toks.size());
+
+    ASSERT_EQ(tok::text,                 Toks[0].getKind());
+    ASSERT_EQ(StringRef(" Meow "),       Toks[0].getText());
+
+    ASSERT_EQ(tok::verbatim_block_begin, Toks[1].getKind());
+    ASSERT_EQ(StringRef("verbatim"),     Toks[1].getVerbatimBlockName());
+
+    ASSERT_EQ(tok::verbatim_block_line,  Toks[2].getKind());
+    ASSERT_EQ(StringRef(" aaa "),        Toks[2].getVerbatimBlockText());
+
+    ASSERT_EQ(tok::newline,              Toks[3].getKind());
+    ASSERT_EQ(tok::newline,              Toks[4].getKind());
+  }
+}
+
+// Complex test for verbatim blocks.
+TEST_F(CommentLexerTest, VerbatimBlock5) {
+  const char *Source =
+    "/* Meow \\verbatim aaa\\$\\@\n"
+    "bbb \\endverbati\r"
+    "ccc\r\n"
+    "ddd \\endverbatim Blah \\verbatim eee\n"
+    "\\endverbatim BlahBlah*/";
+  std::vector<Token> Toks;
+
+  lexString(Source, Toks);
+
+  ASSERT_EQ(14U, Toks.size());
+
+  ASSERT_EQ(tok::text,                 Toks[0].getKind());
+  ASSERT_EQ(StringRef(" Meow "),       Toks[0].getText());
+
+  ASSERT_EQ(tok::verbatim_block_begin, Toks[1].getKind());
+  ASSERT_EQ(StringRef("verbatim"),     Toks[1].getVerbatimBlockName());
+
+  ASSERT_EQ(tok::verbatim_block_line,  Toks[2].getKind());
+  ASSERT_EQ(StringRef(" aaa\\$\\@\n"), Toks[2].getVerbatimBlockText());
+
+  ASSERT_EQ(tok::verbatim_block_line,  Toks[3].getKind());
+  ASSERT_EQ(StringRef("bbb \\endverbati\r"), Toks[3].getVerbatimBlockText());
+
+  ASSERT_EQ(tok::verbatim_block_line,  Toks[4].getKind());
+  ASSERT_EQ(StringRef("ccc\r\n"),      Toks[4].getVerbatimBlockText());
+
+  ASSERT_EQ(tok::verbatim_block_line,  Toks[5].getKind());
+  ASSERT_EQ(StringRef("ddd "),         Toks[5].getVerbatimBlockText());
+
+  ASSERT_EQ(tok::verbatim_block_end,   Toks[6].getKind());
+  ASSERT_EQ(StringRef("endverbatim"),  Toks[6].getVerbatimBlockName());
+
+  ASSERT_EQ(tok::text,                 Toks[7].getKind());
+  ASSERT_EQ(StringRef(" Blah "),       Toks[7].getText());
+
+  ASSERT_EQ(tok::verbatim_block_begin, Toks[8].getKind());
+  ASSERT_EQ(StringRef("verbatim"),     Toks[8].getVerbatimBlockName());
+
+  ASSERT_EQ(tok::verbatim_block_line,  Toks[9].getKind());
+  ASSERT_EQ(StringRef(" eee\n"),       Toks[9].getVerbatimBlockText());
+
+  ASSERT_EQ(tok::verbatim_block_end,   Toks[10].getKind());
+  ASSERT_EQ(StringRef("endverbatim"),  Toks[10].getVerbatimBlockName());
+
+  ASSERT_EQ(tok::text,                 Toks[11].getKind());
+  ASSERT_EQ(StringRef(" BlahBlah"),    Toks[11].getText());
+
+  ASSERT_EQ(tok::newline,              Toks[12].getKind());
+  ASSERT_EQ(tok::newline,              Toks[13].getKind());
+}
+
+// LaTeX verbatim blocks.
+TEST_F(CommentLexerTest, VerbatimBlock6) {
+  const char *Source =
+    "/// \\f$ Aaa \\f$ \\f[ Bbb \\f] \\f{ Ccc \\f}";
+  std::vector<Token> Toks;
+
+  lexString(Source, Toks);
+
+  ASSERT_EQ(13U, Toks.size());
+
+  ASSERT_EQ(tok::text,                 Toks[0].getKind());
+  ASSERT_EQ(StringRef(" "),            Toks[0].getText());
+
+  ASSERT_EQ(tok::verbatim_block_begin, Toks[1].getKind());
+  ASSERT_EQ(StringRef("f$"),           Toks[1].getVerbatimBlockName());
+
+  ASSERT_EQ(tok::verbatim_block_line,  Toks[2].getKind());
+  ASSERT_EQ(StringRef(" Aaa "),        Toks[2].getVerbatimBlockText());
+
+  ASSERT_EQ(tok::verbatim_block_end,   Toks[3].getKind());
+  ASSERT_EQ(StringRef("f$"),           Toks[3].getVerbatimBlockName());
+
+  ASSERT_EQ(tok::text,                 Toks[4].getKind());
+  ASSERT_EQ(StringRef(" "),            Toks[4].getText());
+
+  ASSERT_EQ(tok::verbatim_block_begin, Toks[5].getKind());
+  ASSERT_EQ(StringRef("f["),           Toks[5].getVerbatimBlockName());
+
+  ASSERT_EQ(tok::verbatim_block_line,  Toks[6].getKind());
+  ASSERT_EQ(StringRef(" Bbb "),        Toks[6].getVerbatimBlockText());
+
+  ASSERT_EQ(tok::verbatim_block_end,   Toks[7].getKind());
+  ASSERT_EQ(StringRef("f]"),           Toks[7].getVerbatimBlockName());
+
+  ASSERT_EQ(tok::text,                 Toks[8].getKind());
+  ASSERT_EQ(StringRef(" "),            Toks[8].getText());
+
+  ASSERT_EQ(tok::verbatim_block_begin, Toks[9].getKind());
+  ASSERT_EQ(StringRef("f{"),           Toks[9].getVerbatimBlockName());
+
+  ASSERT_EQ(tok::verbatim_block_line,  Toks[10].getKind());
+  ASSERT_EQ(StringRef(" Ccc "),        Toks[10].getVerbatimBlockText());
+
+  ASSERT_EQ(tok::verbatim_block_end,   Toks[11].getKind());
+  ASSERT_EQ(StringRef("f}"),           Toks[11].getVerbatimBlockName());
+
+  ASSERT_EQ(tok::newline,              Toks[12].getKind());
+}
+
+// Empty verbatim line.
+TEST_F(CommentLexerTest, VerbatimLine1) {
+  const char *Sources[] = {
+    "/// \\fn\n//",
+    "/** \\fn*/"
+  };
+
+  for (size_t i = 0, e = array_lengthof(Sources); i != e; i++) {
+    std::vector<Token> Toks;
+
+    lexString(Sources[i], Toks);
+
+    ASSERT_EQ(4U, Toks.size());
+
+    ASSERT_EQ(tok::text,          Toks[0].getKind());
+    ASSERT_EQ(StringRef(" "),     Toks[0].getText());
+
+    ASSERT_EQ(tok::verbatim_line, Toks[1].getKind());
+    ASSERT_EQ(StringRef("fn"),    Toks[1].getVerbatimLineName());
+    ASSERT_EQ(StringRef(""),      Toks[1].getVerbatimLineText());
+
+    ASSERT_EQ(tok::newline,       Toks[2].getKind());
+    ASSERT_EQ(tok::newline,       Toks[3].getKind());
+  }
+}
+
+// Verbatim line with Doxygen escape sequences, which should not be expanded.
+TEST_F(CommentLexerTest, VerbatimLine2) {
+  const char *Sources[] = {
+    "/// \\fn void *foo(const char *zzz = \"\\$\");\n//",
+    "/** \\fn void *foo(const char *zzz = \"\\$\");*/"
+  };
+
+  for (size_t i = 0, e = array_lengthof(Sources); i != e; i++) {
+    std::vector<Token> Toks;
+
+    lexString(Sources[i], Toks);
+
+    ASSERT_EQ(4U, Toks.size());
+
+    ASSERT_EQ(tok::text,          Toks[0].getKind());
+    ASSERT_EQ(StringRef(" "),     Toks[0].getText());
+
+    ASSERT_EQ(tok::verbatim_line, Toks[1].getKind());
+    ASSERT_EQ(StringRef("fn"),    Toks[1].getVerbatimLineName());
+    ASSERT_EQ(StringRef(" void *foo(const char *zzz = \"\\$\");"),
+                                  Toks[1].getVerbatimLineText());
+
+    ASSERT_EQ(tok::newline,       Toks[2].getKind());
+    ASSERT_EQ(tok::newline,       Toks[3].getKind());
+  }
+}
+
+// Verbatim line should not eat anything from next source line.
+TEST_F(CommentLexerTest, VerbatimLine3) {
+  const char *Source =
+    "/** \\fn void *foo(const char *zzz = \"\\$\");\n"
+    " * Meow\n"
+    " */";
+
+  std::vector<Token> Toks;
+
+  lexString(Source, Toks);
+
+  ASSERT_EQ(8U, Toks.size());
+
+  ASSERT_EQ(tok::text,          Toks[0].getKind());
+  ASSERT_EQ(StringRef(" "),     Toks[0].getText());
+
+  ASSERT_EQ(tok::verbatim_line, Toks[1].getKind());
+  ASSERT_EQ(StringRef("fn"),    Toks[1].getVerbatimLineName());
+  ASSERT_EQ(StringRef(" void *foo(const char *zzz = \"\\$\");"),
+                                Toks[1].getVerbatimLineText());
+  ASSERT_EQ(tok::newline,       Toks[2].getKind());
+
+  ASSERT_EQ(tok::text,          Toks[3].getKind());
+  ASSERT_EQ(StringRef(" Meow"), Toks[3].getText());
+  ASSERT_EQ(tok::newline,       Toks[4].getKind());
+
+  ASSERT_EQ(tok::text,          Toks[5].getKind());
+  ASSERT_EQ(StringRef(" "),     Toks[5].getText());
+
+  ASSERT_EQ(tok::newline,       Toks[6].getKind());
+  ASSERT_EQ(tok::newline,       Toks[7].getKind());
+}
+
+TEST_F(CommentLexerTest, HTML1) {
+  const char *Source =
+    "// <";
+
+  std::vector<Token> Toks;
+
+  lexString(Source, Toks);
+
+  ASSERT_EQ(3U, Toks.size());
+
+  ASSERT_EQ(tok::text,      Toks[0].getKind());
+  ASSERT_EQ(StringRef(" "), Toks[0].getText());
+
+  ASSERT_EQ(tok::text,      Toks[1].getKind());
+  ASSERT_EQ(StringRef("<"), Toks[1].getText());
+
+  ASSERT_EQ(tok::newline,   Toks[2].getKind());
+}
+
+TEST_F(CommentLexerTest, HTML2) {
+  const char *Sources[] = {
+    "// <tag",
+    "// <tag "
+  };
+
+  for (size_t i = 0, e = array_lengthof(Sources); i != e; i++) {
+    std::vector<Token> Toks;
+
+    lexString(Sources[i], Toks);
+
+    ASSERT_EQ(3U, Toks.size());
+
+    ASSERT_EQ(tok::text,          Toks[0].getKind());
+    ASSERT_EQ(StringRef(" "),     Toks[0].getText());
+
+    ASSERT_EQ(tok::html_tag_open, Toks[1].getKind());
+    ASSERT_EQ(StringRef("tag"),   Toks[1].getHTMLTagOpenName());
+
+    ASSERT_EQ(tok::newline,       Toks[2].getKind());
+  }
+}
+
+TEST_F(CommentLexerTest, HTML3) {
+  const char *Source = "// <tag=";
+
+  std::vector<Token> Toks;
+
+  lexString(Source, Toks);
+
+  ASSERT_EQ(4U, Toks.size());
+
+  ASSERT_EQ(tok::text,          Toks[0].getKind());
+  ASSERT_EQ(StringRef(" "),     Toks[0].getText());
+
+  ASSERT_EQ(tok::html_tag_open, Toks[1].getKind());
+  ASSERT_EQ(StringRef("tag"),   Toks[1].getHTMLTagOpenName());
+
+  ASSERT_EQ(tok::text,          Toks[2].getKind());
+  ASSERT_EQ(StringRef("="),     Toks[2].getText());
+
+  ASSERT_EQ(tok::newline,       Toks[3].getKind());
+}
+
+TEST_F(CommentLexerTest, HTML4) {
+  const char *Sources[] = {
+    "// <tag attr",
+    "// <tag attr "
+  };
+
+  for (size_t i = 0, e = array_lengthof(Sources); i != e; i++) {
+    std::vector<Token> Toks;
+
+    lexString(Sources[i], Toks);
+
+    ASSERT_EQ(4U, Toks.size());
+
+    ASSERT_EQ(tok::text,          Toks[0].getKind());
+    ASSERT_EQ(StringRef(" "),     Toks[0].getText());
+
+    ASSERT_EQ(tok::html_tag_open, Toks[1].getKind());
+    ASSERT_EQ(StringRef("tag"),   Toks[1].getHTMLTagOpenName());
+
+    ASSERT_EQ(tok::html_ident,    Toks[2].getKind());
+    ASSERT_EQ(StringRef("attr"),  Toks[2].getHTMLIdent());
+
+    ASSERT_EQ(tok::newline,       Toks[3].getKind());
+  }
+}
+
+TEST_F(CommentLexerTest, HTML5) {
+  const char *Sources[] = {
+    "// <tag attr=",
+    "// <tag attr ="
+  };
+
+  for (size_t i = 0, e = array_lengthof(Sources); i != e; i++) {
+    std::vector<Token> Toks;
+
+    lexString(Sources[i], Toks);
+
+    ASSERT_EQ(5U, Toks.size());
+
+    ASSERT_EQ(tok::text,          Toks[0].getKind());
+    ASSERT_EQ(StringRef(" "),     Toks[0].getText());
+
+    ASSERT_EQ(tok::html_tag_open, Toks[1].getKind());
+    ASSERT_EQ(StringRef("tag"),   Toks[1].getHTMLTagOpenName());
+
+    ASSERT_EQ(tok::html_ident,    Toks[2].getKind());
+    ASSERT_EQ(StringRef("attr"),  Toks[2].getHTMLIdent());
+
+    ASSERT_EQ(tok::html_equals,   Toks[3].getKind());
+
+    ASSERT_EQ(tok::newline,       Toks[4].getKind());
+  }
+}
+
+TEST_F(CommentLexerTest, HTML6) {
+  const char *Sources[] = {
+    "// <tag attr=\"",
+    "// <tag attr = \"",
+    "// <tag attr=\'",
+    "// <tag attr = \'"
+  };
+
+  for (size_t i = 0, e = array_lengthof(Sources); i != e; i++) {
+    std::vector<Token> Toks;
+
+    lexString(Sources[i], Toks);
+
+    ASSERT_EQ(6U, Toks.size());
+
+    ASSERT_EQ(tok::text,               Toks[0].getKind());
+    ASSERT_EQ(StringRef(" "),          Toks[0].getText());
+
+    ASSERT_EQ(tok::html_tag_open,      Toks[1].getKind());
+    ASSERT_EQ(StringRef("tag"),        Toks[1].getHTMLTagOpenName());
+
+    ASSERT_EQ(tok::html_ident,         Toks[2].getKind());
+    ASSERT_EQ(StringRef("attr"),       Toks[2].getHTMLIdent());
+
+    ASSERT_EQ(tok::html_equals,        Toks[3].getKind());
+
+    ASSERT_EQ(tok::html_quoted_string, Toks[4].getKind());
+    ASSERT_EQ(StringRef(""),           Toks[4].getHTMLQuotedString());
+
+    ASSERT_EQ(tok::newline,            Toks[5].getKind());
+  }
+}
+
+TEST_F(CommentLexerTest, HTML7) {
+  const char *Source = "// <tag attr=@";
+
+  std::vector<Token> Toks;
+
+  lexString(Source, Toks);
+
+  ASSERT_EQ(6U, Toks.size());
+
+  ASSERT_EQ(tok::text,          Toks[0].getKind());
+  ASSERT_EQ(StringRef(" "),     Toks[0].getText());
+
+  ASSERT_EQ(tok::html_tag_open, Toks[1].getKind());
+  ASSERT_EQ(StringRef("tag"),   Toks[1].getHTMLTagOpenName());
+
+  ASSERT_EQ(tok::html_ident,    Toks[2].getKind());
+  ASSERT_EQ(StringRef("attr"),  Toks[2].getHTMLIdent());
+
+  ASSERT_EQ(tok::html_equals,   Toks[3].getKind());
+
+  ASSERT_EQ(tok::text,          Toks[4].getKind());
+  ASSERT_EQ(StringRef("@"),     Toks[4].getText());
+
+  ASSERT_EQ(tok::newline,       Toks[5].getKind());
+}
+
+TEST_F(CommentLexerTest, HTML8) {
+  const char *Sources[] = {
+    "// <tag attr=\"val\\\"\\'val",
+    "// <tag attr=\"val\\\"\\'val\"",
+    "// <tag attr=\'val\\\"\\'val",
+    "// <tag attr=\'val\\\"\\'val\'"
+  };
+
+  for (size_t i = 0, e = array_lengthof(Sources); i != e; i++) {
+    std::vector<Token> Toks;
+
+    lexString(Sources[i], Toks);
+
+    ASSERT_EQ(6U, Toks.size());
+
+    ASSERT_EQ(tok::text,                  Toks[0].getKind());
+    ASSERT_EQ(StringRef(" "),             Toks[0].getText());
+
+    ASSERT_EQ(tok::html_tag_open,         Toks[1].getKind());
+    ASSERT_EQ(StringRef("tag"),           Toks[1].getHTMLTagOpenName());
+
+    ASSERT_EQ(tok::html_ident,            Toks[2].getKind());
+    ASSERT_EQ(StringRef("attr"),          Toks[2].getHTMLIdent());
+
+    ASSERT_EQ(tok::html_equals,           Toks[3].getKind());
+
+    ASSERT_EQ(tok::html_quoted_string,    Toks[4].getKind());
+    ASSERT_EQ(StringRef("val\\\"\\'val"), Toks[4].getHTMLQuotedString());
+
+    ASSERT_EQ(tok::newline,               Toks[5].getKind());
+  }
+}
+
+TEST_F(CommentLexerTest, HTML9) {
+  const char *Sources[] = {
+    "// <tag attr=\"val\\\"\\'val\">",
+    "// <tag attr=\'val\\\"\\'val\'>"
+  };
+
+  for (size_t i = 0, e = array_lengthof(Sources); i != e; i++) {
+    std::vector<Token> Toks;
+
+    lexString(Sources[i], Toks);
+
+    ASSERT_EQ(7U, Toks.size());
+
+    ASSERT_EQ(tok::text,                  Toks[0].getKind());
+    ASSERT_EQ(StringRef(" "),             Toks[0].getText());
+
+    ASSERT_EQ(tok::html_tag_open,         Toks[1].getKind());
+    ASSERT_EQ(StringRef("tag"),           Toks[1].getHTMLTagOpenName());
+
+    ASSERT_EQ(tok::html_ident,            Toks[2].getKind());
+    ASSERT_EQ(StringRef("attr"),          Toks[2].getHTMLIdent());
+
+    ASSERT_EQ(tok::html_equals,           Toks[3].getKind());
+
+    ASSERT_EQ(tok::html_quoted_string,    Toks[4].getKind());
+    ASSERT_EQ(StringRef("val\\\"\\'val"), Toks[4].getHTMLQuotedString());
+
+    ASSERT_EQ(tok::html_greater,          Toks[5].getKind());
+
+    ASSERT_EQ(tok::newline,               Toks[6].getKind());
+  }
+}
+
+TEST_F(CommentLexerTest, HTML10) {
+  const char *Source = "// </";
+
+  std::vector<Token> Toks;
+
+  lexString(Source, Toks);
+
+  ASSERT_EQ(3U, Toks.size());
+
+  ASSERT_EQ(tok::text,           Toks[0].getKind());
+  ASSERT_EQ(StringRef(" "),      Toks[0].getText());
+
+  ASSERT_EQ(tok::html_tag_close, Toks[1].getKind());
+  ASSERT_EQ(StringRef(""),       Toks[1].getHTMLTagCloseName());
+
+  ASSERT_EQ(tok::newline,        Toks[2].getKind());
+}
+
+
+TEST_F(CommentLexerTest, HTML11) {
+  const char *Source = "// </@";
+
+  std::vector<Token> Toks;
+
+  lexString(Source, Toks);
+
+  ASSERT_EQ(4U, Toks.size());
+
+  ASSERT_EQ(tok::text,           Toks[0].getKind());
+  ASSERT_EQ(StringRef(" "),      Toks[0].getText());
+
+  ASSERT_EQ(tok::html_tag_close, Toks[1].getKind());
+  ASSERT_EQ(StringRef(""),       Toks[1].getHTMLTagCloseName());
+
+  ASSERT_EQ(tok::text,           Toks[2].getKind());
+  ASSERT_EQ(StringRef("@"),      Toks[2].getText());
+
+  ASSERT_EQ(tok::newline,        Toks[3].getKind());
+}
+
+TEST_F(CommentLexerTest, HTML12) {
+  const char *Sources[] = {
+    "// </tag",
+    "// </tag>",
+    "// </ tag>",
+    "// </ tag >"
+  };
+
+  for (size_t i = 0, e = array_lengthof(Sources); i != e; i++) {
+    std::vector<Token> Toks;
+
+    lexString(Sources[i], Toks);
+
+    ASSERT_EQ(3U, Toks.size());
+
+    ASSERT_EQ(tok::text,           Toks[0].getKind());
+    ASSERT_EQ(StringRef(" "),      Toks[0].getText());
+
+    ASSERT_EQ(tok::html_tag_close, Toks[1].getKind());
+    ASSERT_EQ(StringRef("tag"),    Toks[1].getHTMLTagCloseName());
+
+    ASSERT_EQ(tok::newline,        Toks[2].getKind());
+  }
+}
+
+TEST_F(CommentLexerTest, MultipleComments) {
+  const char *Source =
+    "// Aaa\n"
+    "/// Bbb\n"
+    "/* Ccc\n"
+    " * Ddd*/\n"
+    "/** Eee*/";
+
+  std::vector<Token> Toks;
+
+  lexString(Source, Toks);
+
+  ASSERT_EQ(12U, Toks.size());
+
+  ASSERT_EQ(tok::text,           Toks[0].getKind());
+  ASSERT_EQ(StringRef(" Aaa"),   Toks[0].getText());
+  ASSERT_EQ(tok::newline,        Toks[1].getKind());
+
+  ASSERT_EQ(tok::text,           Toks[2].getKind());
+  ASSERT_EQ(StringRef(" Bbb"),   Toks[2].getText());
+  ASSERT_EQ(tok::newline,        Toks[3].getKind());
+
+  ASSERT_EQ(tok::text,           Toks[4].getKind());
+  ASSERT_EQ(StringRef(" Ccc"),   Toks[4].getText());
+  ASSERT_EQ(tok::newline,        Toks[5].getKind());
+
+  ASSERT_EQ(tok::text,           Toks[6].getKind());
+  ASSERT_EQ(StringRef(" Ddd"),   Toks[6].getText());
+  ASSERT_EQ(tok::newline,        Toks[7].getKind());
+  ASSERT_EQ(tok::newline,        Toks[8].getKind());
+
+  ASSERT_EQ(tok::text,           Toks[9].getKind());
+  ASSERT_EQ(StringRef(" Eee"),   Toks[9].getText());
+
+  ASSERT_EQ(tok::newline,        Toks[10].getKind());
+  ASSERT_EQ(tok::newline,        Toks[11].getKind());
+}
+
+} // end namespace comments
+} // end namespace clang
+
diff --git a/unittests/AST/Makefile b/unittests/AST/Makefile
new file mode 100644
index 0000000000..b25243f0f7
--- /dev/null
+++ b/unittests/AST/Makefile
@@ -0,0 +1,15 @@
+##===- unittests/AST/Makefile ------------------------------*- Makefile -*-===##
+#
+#                     The LLVM Compiler Infrastructure
+#
+# This file is distributed under the University of Illinois Open Source
+# License. See LICENSE.TXT for details.
+#
+##===----------------------------------------------------------------------===##
+
+CLANG_LEVEL = ../..
+TESTNAME = AST
+LINK_COMPONENTS := support mc
+USEDLIBS = clangAST.a clangBasic.a
+
+include $(CLANG_LEVEL)/unittests/Makefile
diff --git a/unittests/Makefile b/unittests/Makefile
index 05449d8ccf..b9f3c3f63d 100644
--- a/unittests/Makefile
+++ b/unittests/Makefile
@@ -14,7 +14,7 @@ ifndef CLANG_LEVEL
 
 IS_UNITTEST_LEVEL := 1
 CLANG_LEVEL := ..
-PARALLEL_DIRS = Basic Frontend Lex Tooling
+PARALLEL_DIRS = Basic AST Frontend Lex Tooling
 
 endif  # CLANG_LEVEL