Local variable slot allocation is non-optimal. Both variables should be mapped
to the same slot:

    public static void main(String argv[]) {
{
int x = 3;
System.out.println(x);
}
{
int y = 4;
System.out.println(y);
}
    }

Method void main(oak/lang/String [])
   0 iconst_3
   1 istore_1 <<= x
   2 getstatic #5 <Field oak/lang/System.out Loak/io/PrintStream;>
   5 iload_1 1 <<= x
   6 invokevirtual #7 <Method oak/io/PrintStream.println(I)V>
   9 iconst_4
  10 istore_2 <<= y
  11 getstatic #5 <Field oak/lang/System.out Loak/io/PrintStream;>
  14 iload_2 2 <<= y
  15 invokevirtual #7 <Method oak/io/PrintStream.println(I)V>
  18 return