Swift: cache some predicated.

swift/ql/lib/codeql/swift/elements/decl/MethodDecl.qll

@@ -26,7 +26,7 @@ class MethodDecl extends AbstractFunctionDecl {
    * Holds if this function is called `funcName` and its a member of a
    * class, struct, extension, enum or protocol call `typeName`.
    */
-  predicate hasQualifiedName(string typeName, string funcName) {
+  cached predicate hasQualifiedName(string typeName, string funcName) {
     this.getName() = funcName and
     (
       exists(NominalTypeDecl c |

swift/ql/lib/codeql/swift/elements/decl/TypeDecl.qll

@@ -26,7 +26,7 @@ class TypeDecl extends TypeDeclBase {
    * The name and full name of `A` is `A`. The name of `B` is `B`, but the
    * full name of `B` is `A.B`.
    */
-  string getFullName() {
+  cached string getFullName() {
     not this.getEnclosingDecl() instanceof TypeDecl and
     result = this.getName()
     or