[clang] NFC: change more places to use Type::getAsTagDecl and friends (#155313)

This changes a bunch of places which use getAs<TagType>, including
derived types, just to obtain the tag definition.

This is preparation for #155028, offloading all the changes that PR used
to introduce which don't depend on any new helpers.

1 files changed, 4 insertions, 10 deletions

diff --git a/clang/lib/CodeGen/CGClass.cpp b/clang/lib/CodeGen/CGClass.cpp
index e9a92ae..10e4543 100644
--- a/clang/lib/CodeGen/CGClass.cpp
+++ b/clang/lib/CodeGen/CGClass.cpp
@@ -1408,13 +1408,10 @@ FieldHasTrivialDestructorBody(ASTContext &Context,
 {
   QualType FieldBaseElementType = Context.getBaseElementType(Field->getType());
 
-  const RecordType *RT = FieldBaseElementType->getAs<RecordType>();
-  if (!RT)
+  auto *FieldClassDecl = FieldBaseElementType->getAsCXXRecordDecl();
+  if (!FieldClassDecl)
     return true;
 
-  auto *FieldClassDecl =
-      cast<CXXRecordDecl>(RT->getOriginalDecl())->getDefinitionOrSelf();
-
   // The destructor for an implicit anonymous union member is never invoked.
   if (FieldClassDecl->isUnion() && FieldClassDecl->isAnonymousStructOrUnion())
     return true;
@@ -2850,13 +2847,10 @@ void CodeGenFunction::EmitVTablePtrCheckForCast(QualType T, Address Derived,
   if (!getLangOpts().CPlusPlus)
     return;
 
-  auto *ClassTy = T->getAs<RecordType>();
-  if (!ClassTy)
+  const auto *ClassDecl = T->getAsCXXRecordDecl();
+  if (!ClassDecl)
     return;
 
-  const auto *ClassDecl =
-      cast<CXXRecordDecl>(ClassTy->getOriginalDecl())->getDefinitionOrSelf();
-
   if (!ClassDecl->isCompleteDefinition() || !ClassDecl->isDynamicClass())
     return;