[APINotes] Introduce APINotes infrastructure in Clang Sema and Frontend

This upstreams more of the Clang API Notes functionality that is
currently implemented in the Apple fork:
https://github.com/apple/llvm-project/tree/next/clang/lib/APINotes

This adds the initial Clang APINotes infrastructure to Clang Sema and
Clang Frontend.

There will shortly be a follow-up patch with the actual usages of this
API. I'm splitting these changes into separate PRs to keep the diffs
easier to review.

1 files changed, 4 insertions, 0 deletions

diff --git a/clang/lib/Frontend/CompilerInstance.cpp b/clang/lib/Frontend/CompilerInstance.cpp
index d749195..be5b38d 100644
--- a/clang/lib/Frontend/CompilerInstance.cpp
+++ b/clang/lib/Frontend/CompilerInstance.cpp
@@ -747,6 +747,10 @@ void CompilerInstance::createSema(TranslationUnitKind TUKind,
                                   CodeCompleteConsumer *CompletionConsumer) {
   TheSema.reset(new Sema(getPreprocessor(), getASTContext(), getASTConsumer(),
                          TUKind, CompletionConsumer));
+
+  // Set up API notes.
+  TheSema->APINotes.setSwiftVersion(getAPINotesOpts().SwiftVersion);
+
   // Attach the external sema source if there is any.
   if (ExternalSemaSrc) {
     TheSema->addExternalSource(ExternalSemaSrc.get());