== t1 ==
fun t1() {
    for (i in 1..2) {
        doSmth(i)
    }
}
---------------------
L0:
    <START>                    
    r(1)                       
    r(2)                       
    call(.., rangeTo)          
    v(i)                       
    w(i)                       
L3:
    jmp?(L2)                       NEXT:[read (Unit), r(i)]          
L4 [loop entry point]:
L5 [body entry point]:
    r(i)                           PREV:[jmp?(L2), jmp?(L4 [loop entry point])]
    call(doSmth, doSmth)       
    jmp?(L4 [loop entry point])    NEXT:[r(i), read (Unit)]          
L2:
    read (Unit)                    PREV:[jmp?(L2), jmp?(L4 [loop entry point])]
L1:
    <END>                          NEXT:[<SINK>]                     
error:
    <ERROR>                        PREV:[]
sink:
    <SINK>                         PREV:[<ERROR>, <END>]
=====================
== doSmth ==
fun doSmth(i: Int) {}
---------------------
L0:
    <START>    
    v(i: Int)  
    w(i)       
    read (Unit)
L1:
    <END>          NEXT:[<SINK>]     
error:
    <ERROR>        PREV:[]
sink:
    <SINK>         PREV:[<ERROR>, <END>]
=====================