Merge pull request swiftlang#31515 from AnthonyLatsis/assert-type-param-requires-class

AST: Assert we were given a type parameter in GenericSignatureImpl::requiresClass

Author: CodaFi

lib/AST/GenericSignature.cpp

@@ -379,7 +379,8 @@ GenericSignatureImpl::lookupConformance(CanType type,
 }
 
 bool GenericSignatureImpl::requiresClass(Type type) {
-  if (!type->isTypeParameter()) return false;
+  assert(type->isTypeParameter() &&
+         "Only type parameters can have superclass requirements");
 
   auto &builder = *getGenericSignatureBuilder();
   auto equivClass =

lib/SIL/IR/AbstractionPattern.cpp

@@ -222,8 +222,7 @@ bool AbstractionPattern::requiresClass() const {
     auto type = getType();
     if (auto archetype = dyn_cast<ArchetypeType>(type))
       return archetype->requiresClass();
-    if (isa<DependentMemberType>(type) ||
-        isa<GenericTypeParamType>(type)) {
+    if (type->isTypeParameter()) {
       if (getKind() == Kind::ClangType) {
         // ObjC generics are always class constrained.
         return true;