// Check types.
	if IsSimple[t.Kind()] {
		return t
	}
	switch t.Kind() {
	case TARRAY, TCHAN, TFUNC, TMAP, TSLICE, TSTRING, TSTRUCT:
		return t
	}
	return nil
}

func FloatForComplex(t *Type) *Type {
	switch t.Kind() {
	case TCOMPLEX64:
		return Types[TFLOAT32]
	case TCOMPLEX128:
		return Types[TFLOAT64]
	}
	base.Fatalf("unexpected type: %v", t)
	return nil
}