[clang] Refactor doc comments to Decls attribution

- Create ASTContext::attachCommentsToJustParsedDecls so we don't have to load external comments in Sema when trying to attach existing comments to just parsed Decls.
- Keep comments ordered and cache their decomposed location - faster SourceLoc-based searching.
- Optimize work with redeclarations.
- Keep one comment per redeclaration chain (represented by canonical Decl) instead of comment per redeclaration.
- For redeclaration chains with no comment attached keep just the last declaration in chain that had no comment instead of every comment-less redeclaration.

Differential Revision: https://reviews.llvm.org/D65301

llvm-svn: 368732

1 files changed, 4 insertions, 14 deletions

diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index 4df0bc12d52..3cda1581b04 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -12465,20 +12465,10 @@ void Sema::ActOnDocumentableDecls(ArrayRef<Decl *> Group) {
     }
   }
 
-  // See if there are any new comments that are not attached to a decl.
-  ArrayRef<RawComment *> Comments = Context.getRawCommentList().getComments();
-  if (!Comments.empty() &&
-      !Comments.back()->isAttached()) {
-    // There is at least one comment that not attached to a decl.
-    // Maybe it should be attached to one of these decls?
-    //
-    // Note that this way we pick up not only comments that precede the
-    // declaration, but also comments that *follow* the declaration -- thanks to
-    // the lookahead in the lexer: we've consumed the semicolon and looked
-    // ahead through comments.
-    for (unsigned i = 0, e = Group.size(); i != e; ++i)
-      Context.getCommentForDecl(Group[i], &PP);
-  }
+  // FIMXE: We assume every Decl in the group is in the same file.
+  // This is false when preprocessor constructs the group from decls in
+  // different files (e. g. macros or #include).
+  Context.attachCommentsToJustParsedDecls(Group, &getPreprocessor());
 }
 
 /// Common checks for a parameter-declaration that should apply to both function