Reland "Give NullabilityKind a printing operator<<"

This reverts commit 5326c9e480d70e16c2504cb5143524aff3ee2605.

The problem that caused the revert was downstream
(missing dep in user of clang).

1 files changed, 14 insertions, 0 deletions

diff --git a/clang/lib/Basic/IdentifierTable.cpp b/clang/lib/Basic/IdentifierTable.cpp
index 97dc5cd..9be42c0 100644
--- a/clang/lib/Basic/IdentifierTable.cpp
+++ b/clang/lib/Basic/IdentifierTable.cpp
@@ -849,6 +849,20 @@ StringRef clang::getNullabilitySpelling(NullabilityKind kind,
   llvm_unreachable("Unknown nullability kind.");
 }
 
+llvm::raw_ostream &operator<<(llvm::raw_ostream &OS, NullabilityKind NK) {
+  switch (NK) {
+  case NullabilityKind::NonNull:
+    return OS << "NonNull";
+  case NullabilityKind::Nullable:
+    return OS << "Nullable";
+  case NullabilityKind::NullableResult:
+    return OS << "NullableResult";
+  case NullabilityKind::Unspecified:
+    return OS << "Unspecified";
+  }
+  llvm_unreachable("Unknown nullability kind.");
+}
+
 diag::kind
 IdentifierTable::getFutureCompatDiagKind(const IdentifierInfo &II,
                                          const LangOptions &LangOpts) {