sil private @_T04nullyycfU_ : $@convention(thin) () -> () {
bb0:
  %0 = alloc_box ${ var Bool }, var, name "b"
  %1 = project_box %0 : ${ var Bool }, 0
  %2 = function_ref @_T04null1fSbSgyF : $@convention(thin) () -> Optional<Bool>
  %3 = apply %2() : $@convention(thin) () -> Optional<Bool>
  switch_enum %3 : $Optional<Bool>, case #Optional.some!enumelt.1: bb2, case #Optional.none!enumelt: bb1

bb1:
  dealloc_box %0 : ${ var Bool }
  br bb4

bb2(%7 : $Bool):
  store %7 to %1 : $*Bool
  br bb3

bb3:
  %10 = function_ref @_T04nullyycfU_yycfU_ : $@convention(thin) (@owned { var Bool }) -> ()
  strong_retain %0 : ${ var Bool }
  %12 = partial_apply %10(%0) : $@convention(thin) (@owned { var Bool }) -> ()
  debug_value %12 : $@callee_owned () -> (), let, name "c"
  strong_release %12 : $@callee_owned () -> ()
  strong_release %0 : ${ var Bool }
  br bb5

bb4:
  br bb5

bb5:
  %18 = tuple ()
  return %18 : $()
}