STEP 0:
    modifications:
        U : A.0.kt -> A.kt
        U : l1.0.kt -> l1.kt
    added file: A.kt, l1.kt
STEP 1:
    modifications:
        U : A.1.kt -> A.kt
    modified ir: A.kt
STEP 2:
    modifications:
        U : A.2.kt -> A.kt
        U : l1.2.kt -> l1.kt
    modified ir: A.kt, l1.kt
STEP 3:
    modifications:
        U : A.3.kt -> A.kt
        U : l1.3.kt -> l1.kt
    modified ir: A.kt, l1.kt
