[Debug Info] Sink type alias check into DbgTy.isForwardDecl (NFC)

Author: adrian-prantl

lib/IRGen/DebugTypeInfo.cpp

@@ -193,6 +193,10 @@ TypeDecl *DebugTypeInfo::getDecl() const {
   return nullptr;
 }
 
+bool DebugTypeInfo::isForwardDecl() const {
+  return isNull() || (!FragmentStorageType && !isa<TypeAliasType>(getType()));
+}
+
 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
 LLVM_DUMP_METHOD void DebugTypeInfo::dump() const {
   llvm::errs() << "[";
@@ -203,7 +207,8 @@ LLVM_DUMP_METHOD void DebugTypeInfo::dump() const {
   if (FragmentStorageType) {
     llvm::errs() << "FragmentStorageType=";
     FragmentStorageType->dump();
-  } else
+  }
+  if (isForwardDecl())
     llvm::errs() << "forward-declared\n";
 }
 #endif

lib/IRGen/DebugTypeInfo.h

@@ -102,8 +102,8 @@ class DebugTypeInfo {
 
   llvm::Type *getFragmentStorageType() const { return FragmentStorageType; }
   Alignment getAlignment() const { return Align; }
-  bool isNull() const { return Type == nullptr; }
-  bool isForwardDecl() const { return FragmentStorageType == nullptr; }
+  bool isNull() const { return !Type; }
+  bool isForwardDecl() const;
   bool isMetadataType() const { return IsMetadataType; }
   bool hasDefaultAlignment() const { return DefaultAlignment; }
   bool isFixedBuffer() const { return IsFixedBuffer; }

lib/IRGen/IRGenDebugInfo.cpp

@@ -2511,7 +2511,7 @@ class IRGenDebugInfoImpl : public IRGenDebugInfo {
 
     // If this is a forward decl, create one for this mangled name and don't
     // cache it.
-    if (DbgTy.isForwardDecl() && !isa<TypeAliasType>(DbgTy.getType())) {
+    if (DbgTy.isForwardDecl()) {
       // In LTO type uniquing is performed based on the UID. Forward
       // declarations may not have a unique ID to avoid a forward declaration
       // winning over a full definition.