[NFC] Move CommentOpts checks to the call sites that depend on it.

[dlj]

Summary

When parsing comments, for example, for -Wdocumentation, slightly different
behaviour occurs when -fparse-all-comments is specified. However, these
differences are subtle:

1. All comments are saved during parsing, regardless of whether they are doc comments or not.
2. "Maybe-doc" comments, like \<, \!, etc, are saved as such, instead of marking them as ordinary comments. The maybe-doc type of comment is never saved otherwise. (Warning on these is the impetus of -Wdocumentation.)
3. All comments are treated as doc comments in ASTContext, even if they are ordinary.

This change moves the logic for checking CommentOptions.ParseAllComments closer
to where it has an effect. The overall logic is unchanged, but checks of the
ParseAllComments flag are now done where the effect will be clearer.

include/clang/AST/ASTContext.h

 public:
   RawCommentList &getRawCommentList() {
     return Comments;
   }
 
   void addComment(const RawComment &RC) {
     assert(LangOpts.RetainCommentsFromSystemHeaders ||
            !SourceMgr.isInSystemHeader(RC.getSourceRange().getBegin()));
-    Comments.addComment(RC, BumpAlloc);
+    Comments.addComment(RC, LangOpts.CommentOpts, BumpAlloc);
   }
 
   /// \brief Return the documentation comment attached to a given declaration.
   /// Returns nullptr if no comment is attached.
   ///
   /// \param OriginalDecl if not nullptr, is set to declaration AST node that
   /// had the comment, if the comment we found comes from a redeclaration.
   const RawComment *

include/clang/AST/RawCommentList.h

enum CommentKind {
     RCK_JavaDoc,      ///< \code /** stuff */ \endcode
     RCK_Qt,           ///< \code /*! stuff */ \endcode, also used by HeaderDoc
     RCK_Merged        ///< Two or more documentation comments merged together
   };
 
   RawComment() : Kind(RCK_Invalid), IsAlmostTrailingComment(false) { }
 
   RawComment(const SourceManager &SourceMgr, SourceRange SR,
-             bool Merged, bool ParseAllComments);
+             const CommentOptions &CommentOpts, bool Merged);
 
   CommentKind getKind() const LLVM_READONLY {
     return (CommentKind) Kind;
   }
 
   bool isInvalid() const LLVM_READONLY {
     return Kind == RCK_Invalid;
   }
public:
   /// \code //< stuff \endcode
   /// \code /*< stuff */ \endcode
   bool isAlmostTrailingComment() const LLVM_READONLY {
     return IsAlmostTrailingComment;
   }
 
   /// Returns true if this comment is not a documentation comment.
   bool isOrdinary() const LLVM_READONLY {
-    return ((Kind == RCK_OrdinaryBCPL) || (Kind == RCK_OrdinaryC)) &&
-        !ParseAllComments;
+    return ((Kind == RCK_OrdinaryBCPL) || (Kind == RCK_OrdinaryC));
   }
 
   /// Returns true if this comment any kind of a documentation comment.
   bool isDocumentation() const LLVM_READONLY {
     return !isInvalid() && !isOrdinary();
   }
 
-  /// Returns whether we are parsing all comments.
-  bool isParseAllComments() const LLVM_READONLY {
-    return ParseAllComments;
-  }
-
   /// Returns raw comment text with comment markers.
   StringRef getRawText(const SourceManager &SourceMgr) const {
     if (RawTextValid)
       return RawText;
 
     RawText = getRawTextSlow(SourceMgr);
     RawTextValid = true;
     return RawText;
private:
   unsigned Kind : 3;
 
   /// True if comment is attached to a declaration in ASTContext.
   bool IsAttached : 1;
 
   bool IsTrailingComment : 1;
   bool IsAlmostTrailingComment : 1;
 
-  /// When true, ordinary comments starting with "//" and "/*" will be
-  /// considered as documentation comments.
-  bool ParseAllComments : 1;
-
   /// \brief Constructor for AST deserialization.
   RawComment(SourceRange SR, CommentKind K, bool IsTrailingComment,
-             bool IsAlmostTrailingComment,
-             bool ParseAllComments) :
+             bool IsAlmostTrailingComment) :
     Range(SR), RawTextValid(false), BriefTextValid(false), Kind(K),
     IsAttached(false), IsTrailingComment(IsTrailingComment),
-    IsAlmostTrailingComment(IsAlmostTrailingComment),
-    ParseAllComments(ParseAllComments)
+    IsAlmostTrailingComment(IsAlmostTrailingComment)
   { }
 
   StringRef getRawTextSlow(const SourceManager &SourceMgr) const;
 
   const char *extractBriefText(const ASTContext &Context) const;
 
   friend class ASTReader;
 };

 };
 
 /// \brief This class represents all comments included in the translation unit,
 /// sorted in order of appearance in the translation unit.
 class RawCommentList {
 public:
   RawCommentList(SourceManager &SourceMgr) : SourceMgr(SourceMgr) {}
 
-  void addComment(const RawComment &RC, llvm::BumpPtrAllocator &Allocator);
+  void addComment(const RawComment &RC, const CommentOptions &CommentOpts,
+                  llvm::BumpPtrAllocator &Allocator);
 
   ArrayRef<RawComment *> getComments() const {
     return Comments;
   }
 
 private:
   SourceManager &SourceMgr;
   std::vector<RawComment *> Comments;

lib/AST/ASTContext.cpp

#endif
 
   // Find the comment that occurs just after this declaration.
   ArrayRef<RawComment *>::iterator Comment;
   {
     // When searching for comments during parsing, the comment we are looking
     // for is usually among the last two comments we parsed -- check them
     // first.
     RawComment CommentAtDeclLoc(
-        SourceMgr, SourceRange(DeclLoc), false,
-        LangOpts.CommentOpts.ParseAllComments);
+        SourceMgr, SourceRange(DeclLoc), LangOpts.CommentOpts, false);
     BeforeThanCompare<RawComment> Compare(SourceMgr);
     ArrayRef<RawComment *>::iterator MaybeBeforeDecl = RawComments.end() - 1;
     bool Found = Compare(*MaybeBeforeDecl, &CommentAtDeclLoc);
     if (!Found && RawComments.size() >= 2) {
       MaybeBeforeDecl--;
       Found = Compare(*MaybeBeforeDecl, &CommentAtDeclLoc);
     }
 
#endif
   }
 
   // Decompose the location for the declaration and find the beginning of the
   // file buffer.
   std::pair<FileID, unsigned> DeclLocDecomp = SourceMgr.getDecomposedLoc(DeclLoc);
 
   // First check whether we have a trailing comment.
   if (Comment != RawComments.end() &&
-      (*Comment)->isDocumentation() && (*Comment)->isTrailingComment() &&
+      ((*Comment)->isDocumentation() || LangOpts.CommentOpts.ParseAllComments)
+      && (*Comment)->isTrailingComment() &&
       (isa<FieldDecl>(D) || isa<EnumConstantDecl>(D) || isa<VarDecl>(D) ||
        isa<ObjCMethodDecl>(D) || isa<ObjCPropertyDecl>(D))) {
     std::pair<FileID, unsigned> CommentBeginDecomp
       = SourceMgr.getDecomposedLoc((*Comment)->getSourceRange().getBegin());
     // Check that Doxygen trailing comment comes after the declaration, starts
     // on the same line and in the same file as the declaration.
     if (DeclLocDecomp.first == CommentBeginDecomp.first &&
         SourceMgr.getLineNumber(DeclLocDecomp.first, DeclLocDecomp.second)
           == SourceMgr.getLineNumber(CommentBeginDecomp.first,
                                      CommentBeginDecomp.second)) {
       return *Comment;
     }
   }
 
   // The comment just after the declaration was not a trailing comment.
   // Let's look at the previous comment.
   if (Comment == RawComments.begin())
     return nullptr;
   --Comment;
 
   // Check that we actually have a non-member Doxygen comment.
-  if (!(*Comment)->isDocumentation() || (*Comment)->isTrailingComment())
+  if (!((*Comment)->isDocumentation() ||
+        LangOpts.CommentOpts.ParseAllComments) ||
+      (*Comment)->isTrailingComment())
     return nullptr;
 
   // Decompose the end of the comment.
   std::pair<FileID, unsigned> CommentEndDecomp
     = SourceMgr.getDecomposedLoc((*Comment)->getSourceRange().getEnd());
 
   // If the comment and the declaration aren't in the same file, then they
   // aren't related.
if (Pos != RedeclComments.end()) {
       Raw.setOriginalDecl(I);
       RedeclComments[I] = Raw;
       if (RC)
         break;
     }
   }
 
   // If we found a comment, it should be a documentation comment.
-  assert(!RC || RC->isDocumentation());
+  assert(!RC || RC->isDocumentation() || LangOpts.CommentOpts.ParseAllComments);
 
   if (OriginalDecl)
     *OriginalDecl = OriginalDeclForRC;
 
   // Update cache for every declaration in the redeclaration chain.
   RawCommentAndCacheFlags Raw;
   Raw.setRaw(RC);
   Raw.setKind(RawCommentAndCacheFlags::FromRedecl);

lib/AST/RawCommentList.cpp

 
 /// Returns whether `K` is an ordinary comment kind.
 static bool isOrdinaryKind(RawComment::CommentKind K) {
   return (K == RawComment::RCK_OrdinaryBCPL) ||
          (K == RawComment::RCK_OrdinaryC);
 }
 
 RawComment::RawComment(const SourceManager &SourceMgr, SourceRange SR,
-                       bool Merged, bool ParseAllComments) :
+                       const CommentOptions &CommentOpts, bool Merged) :
     Range(SR), RawTextValid(false), BriefTextValid(false),
-    IsAttached(false), IsTrailingComment(false), IsAlmostTrailingComment(false),
-    ParseAllComments(ParseAllComments) {
+    IsAttached(false), IsTrailingComment(false),
+    IsAlmostTrailingComment(false) {
   // Extract raw comment text, if possible.
   if (SR.getBegin() == SR.getEnd() || getRawText(SourceMgr).empty()) {
     Kind = RCK_Invalid;
     return;
   }
 
   // Guess comment kind.
-  std::pair<CommentKind, bool> K = getCommentKind(RawText, ParseAllComments);
+  std::pair<CommentKind, bool> K =
+      getCommentKind(RawText, CommentOpts.ParseAllComments);
 
   // Guess whether an ordinary comment is trailing.
-  if (ParseAllComments && isOrdinaryKind(K.first)) {
+  if (CommentOpts.ParseAllComments && isOrdinaryKind(K.first)) {
     FileID BeginFileID;
     unsigned BeginOffset;
     std::tie(BeginFileID, BeginOffset) =
         SourceMgr.getDecomposedLoc(Range.getBegin());
     if (BeginOffset != 0) {
       bool Invalid = false;
       const char *Buffer =
           SourceMgr.getBufferData(BeginFileID, &Invalid).data();
case '\n':
       break;
     }
   }
 
   return true;
 }
 
 void RawCommentList::addComment(const RawComment &RC,
+                                const CommentOptions &CommentOpts,
                                 llvm::BumpPtrAllocator &Allocator) {
   if (RC.isInvalid())
     return;
 
   // Check if the comments are not in source order.
   while (!Comments.empty() &&
          !SourceMgr.isBeforeInTranslationUnit(Comments.back()->getLocStart(),
                                               RC.getLocStart())) {
     // If they are, just pop a few last comments that don't fit.
     // This happens if an \#include directive contains comments.
     Comments.pop_back();
   }
 
   // Ordinary comments are not interesting for us.
-  if (RC.isOrdinary())
+  if (RC.isOrdinary() && !CommentOpts.ParseAllComments)
     return;
 
   // If this is the first Doxygen comment, save it (because there isn't
   // anything to merge it with).
   if (Comments.empty()) {
     Comments.push_back(new (Allocator) RawComment(RC));
     return;
   }
void RawCommentList::addComment(const RawComment &RC,
   // Merge comments if they are on same or consecutive lines.
   if ((C1.isTrailingComment() == C2.isTrailingComment() ||
        (C1.isTrailingComment() && !C2.isTrailingComment() &&
         isOrdinaryKind(C2.getKind()) &&
         commentsStartOnSameColumn(SourceMgr, C1, C2))) &&
       onlyWhitespaceBetween(SourceMgr, C1.getLocEnd(), C2.getLocStart(),
                             /*MaxNewlinesAllowed=*/1)) {
     SourceRange MergedRange(C1.getLocStart(), C2.getLocEnd());
-    *Comments.back() = RawComment(SourceMgr, MergedRange, true,
-                                  RC.isParseAllComments());
+    *Comments.back() = RawComment(SourceMgr, MergedRange, CommentOpts, true);
   } else {
     Comments.push_back(new (Allocator) RawComment(RC));
   }
 }
 
 void RawCommentList::addDeserializedComments(ArrayRef<RawComment *> DeserializedComments) {
   std::vector<RawComment *> MergedComments;
   MergedComments.reserve(Comments.size() + DeserializedComments.size());
 
   std::merge(Comments.begin(), Comments.end(),
              DeserializedComments.begin(), DeserializedComments.end(),
              std::back_inserter(MergedComments),
              BeforeThanCompare<RawComment>(SourceMgr));
   std::swap(Comments, MergedComments);
 }

lib/Sema/Sema.cpp

LambdaScopeInfo *Sema::getCurGenericLambda() {
   return nullptr;
 }
 
 
 void Sema::ActOnComment(SourceRange Comment) {
   if (!LangOpts.RetainCommentsFromSystemHeaders &&
       SourceMgr.isInSystemHeader(Comment.getBegin()))
     return;
-  RawComment RC(SourceMgr, Comment, false,
-                LangOpts.CommentOpts.ParseAllComments);
+  RawComment RC(SourceMgr, Comment, LangOpts.CommentOpts, false);
   if (RC.isAlmostTrailingComment()) {
     SourceRange MagicMarkerRange(Comment.getBegin(),
                                  Comment.getBegin().getLocWithOffset(3));
     StringRef MagicMarkerText;
     switch (RC.getKind()) {
     case RawComment::RCK_OrdinaryBCPL:
       MagicMarkerText = "///<";
       break;

lib/Serialization/ASTReader.cpp

while (true) {
       case COMMENTS_RAW_COMMENT: {
         unsigned Idx = 0;
         SourceRange SR = ReadSourceRange(F, Record, Idx);
         RawComment::CommentKind Kind =
             (RawComment::CommentKind) Record[Idx++];
         bool IsTrailingComment = Record[Idx++];
         bool IsAlmostTrailingComment = Record[Idx++];
         Comments.push_back(new (Context) RawComment(
-            SR, Kind, IsTrailingComment, IsAlmostTrailingComment,
-            Context.getLangOpts().CommentOpts.ParseAllComments));
+            SR, Kind, IsTrailingComment, IsAlmostTrailingComment));
         break;
       }
       }
     }
   NextCursor:
     // De-serialized SourceLocations get negative FileIDs for other modules,
     // potentially invalidating the original order. Sort it again.
     std::sort(Comments.begin(), Comments.end(),