Prevent calling getClassOrBoundGenericClass twice

Author: stzn

lib/SILGen/SILGenExpr.cpp

@@ -3399,10 +3399,10 @@ static ManagedValue emitKeyPathRValueBase(SILGenFunction &subSGF,
 
   // Upcast a class instance to the property's declared type if necessary.
   if (auto propertyClass = storage->getDeclContext()->getSelfClassDecl()) {
+    if (auto selfType = baseType->getAs<DynamicSelfType>())
+      baseType = selfType->getSelfType()->getCanonicalType();
     auto baseClass = baseType->getClassOrBoundGenericClass();
-    if (auto dynamicSelfType = baseType->getAs<DynamicSelfType>()) {
-      baseClass = dynamicSelfType->getSelfType()->getClassOrBoundGenericClass();
-    }
+
     if (baseClass != propertyClass) {
       baseType = baseType->getSuperclassForDecl(propertyClass)
         ->getCanonicalType();