case sub1:
			got = tt.in.subOne()
		default:
			panic("bogus op")
		}
		if got != tt.want {
			t.Errorf("%v add %d = %v; want %v", tt.in, tt.op, got, tt.want)
		}
	}
}

func TestBitsSetFrom(t *testing.T) {
	tests := []struct {
		bit  uint8
		want uint128
	}{
		{0, uint128{^uint64(0), ^uint64(0)}},
		{1, uint128{^uint64(0) >> 1, ^uint64(0)}},
		{63, uint128{1, ^uint64(0)}},