// (therefore SSAable). val is the value to be stored. The function returns an SSA
// value representing a pointer to the autotmp location.
func (s *state) openDeferSave(t *types.Type, val *ssa.Value) *ssa.Value {
	if !ssa.CanSSA(t) {
		s.Fatalf("openDeferSave of non-SSA-able type %v val=%v", t, val)
	}
	if !t.HasPointers() {
		s.Fatalf("openDeferSave of pointerless type %v val=%v", t, val)
	}