== main ==
fun main() {
    while(1 > 0) {
      2
    }
}
---------------------
l0:
    <START>             NEXT:[r(while(1 > 0) { 2 }) ]    PREV:[]
    r(while(1 > 0) {
          2         
        })              NEXT:[r(1)]                      PREV:[<START>]
l2:
l5:
    r(1)                NEXT:[r(0)]                      PREV:[r(while(1 > 0) { 2 }) , jmp(l2)]
    r(0)                NEXT:[r(>)]                      PREV:[r(1)]
    r(>)                NEXT:[r(1 > 0)]                  PREV:[r(0)]
    r(1 > 0)            NEXT:[jf(l3)]                    PREV:[r(>)]
    jf(l3)              NEXT:[read (Unit), r(2)]         PREV:[r(1 > 0)]
l4:
    r(2)                NEXT:[jmp(l2)]                   PREV:[jf(l3)]
    jmp(l2)             NEXT:[r(1)]                      PREV:[r(2)]
l3:
    read (Unit)         NEXT:[<END>]                     PREV:[jf(l3)]
l1:
    <END>               NEXT:[<SINK>]                    PREV:[read (Unit)]
error:
    <ERROR>             NEXT:[]                          PREV:[]
sink:
    <SINK>              NEXT:[]                          PREV:[<END>]
=====================
== dowhile ==
fun dowhile() {
    do {return}
    while(1 > 0)
}
---------------------
l0:
    <START>              NEXT:[r(do {return} while(1 > 0)) ]    PREV:[]
    r(do {return}    
        while(1 > 0))    NEXT:[ret l1]                          PREV:[<START>]
l2:
l4:
    ret l1               NEXT:[<END>]                           PREV:[r(do {return} while(1 > 0)) ]
l5:
-   r(1)                 NEXT:[r(0)]                            PREV:[]
-   r(0)                 NEXT:[r(>)]                            PREV:[]
-   r(>)                 NEXT:[r(1 > 0)]                        PREV:[]
-   r(1 > 0)             NEXT:[jt(l2)]                          PREV:[]
-   jt(l2)               NEXT:[read (Unit), ret l1]             PREV:[]
l3:
-   read (Unit)          NEXT:[<END>]                           PREV:[]
l1:
    <END>                NEXT:[<SINK>]                          PREV:[ret l1]
error:
    <ERROR>              NEXT:[]                                PREV:[]
sink:
    <SINK>               NEXT:[]                                PREV:[<END>]
=====================