== foo ==
fun foo(a: Array<Int>) {
    a[0] += 1
}
---------------------
L0:
    <START>
    v(a: Array<Int>)
    w(a)
    mark({ a[0] += 1 })
    mark(a[0] += 1)
    mark(a[0])
    r(a)
    r(0)
    call(a[0], get)
    r(1)
    call(+=, plus)
    mark(a[0])
    r(a)
    r(0)
    r(1)
    call(a[0], set)
L1:
    <END>                  NEXT:[<SINK>]
error:
    <ERROR>                PREV:[]
sink:
    <SINK>                 PREV:[<ERROR>, <END>]
=====================