NO Initial ITS Start location: __init Program variables: arg1 arg2 0: f1_0_main_Load -> f57_0_loop_GT : arg1'=arg1p1, arg2'=arg2p1, (-arg1p1+arg2 == 0 /\ 1+arg2 > 0 /\ arg1 > 0), cost: 1 1: f57_0_loop_GT -> f57_0_loop_GT : arg1'=arg1p2, arg2'=arg2p2, (-1+arg1 < 0 /\ -1+arg1-arg1p2 == 0), cost: 1 2: f57_0_loop_GT -> f57_0_loop_GT : arg1'=arg1p3, arg2'=arg2p3, (1-arg1p3+arg1 == 0 /\ arg1 > 0), cost: 1 3: __init -> f1_0_main_Load : arg1'=arg1p4, arg2'=arg2p4, T, cost: 1 Chained Linear Paths Start location: __init Program variables: arg1 arg2 1: f57_0_loop_GT -> f57_0_loop_GT : arg1'=arg1p2, arg2'=arg2p2, (-1+arg1 < 0 /\ -1+arg1-arg1p2 == 0), cost: 1 2: f57_0_loop_GT -> f57_0_loop_GT : arg1'=arg1p3, arg2'=arg2p3, (1-arg1p3+arg1 == 0 /\ arg1 > 0), cost: 1 4: __init -> f57_0_loop_GT : arg1'=arg1p1, arg2'=arg2p1, (1+arg2p4 > 0 /\ arg1p4 > 0 /\ -arg1p1+arg2p4 == 0), cost: 1 Eliminating location f1_0_main_Load by chaining: Applied chaining First rule: __init -> f1_0_main_Load : arg1'=arg1p4, arg2'=arg2p4, T, cost: 1 Second rule: f1_0_main_Load -> f57_0_loop_GT : arg1'=arg1p1, arg2'=arg2p1, (-arg1p1+arg2 == 0 /\ 1+arg2 > 0 /\ arg1 > 0), cost: 1 New rule: __init -> f57_0_loop_GT : arg1'=arg1p1, arg2'=arg2p1, (1+arg2p4 > 0 /\ arg1p4 > 0 /\ -arg1p1+arg2p4 == 0), cost: 1 Applied deletion Removed the following rules: 0 3 Simplified Transitions Start location: __init Program variables: arg1 arg2 5: f57_0_loop_GT -> f57_0_loop_GT : arg1'=-1+arg1, arg2'=arg2p2, -1+arg1 < 0, cost: 1 6: f57_0_loop_GT -> f57_0_loop_GT : arg1'=1+arg1, arg2'=arg2p3, arg1 > 0, cost: 1 7: __init -> f57_0_loop_GT : arg1'=arg2p4, arg2'=arg2p1, (1+arg2p4 > 0), cost: 1 Propagated Equalities Original rule: f57_0_loop_GT -> f57_0_loop_GT : arg1'=arg1p2, arg2'=arg2p2, (-1+arg1 < 0 /\ -1+arg1-arg1p2 == 0), cost: 1 New rule: f57_0_loop_GT -> f57_0_loop_GT : arg1'=-1+arg1, arg2'=arg2p2, (0 == 0 /\ -1+arg1 < 0), cost: 1 propagated equality arg1p2 = -1+arg1 Simplified Guard Original rule: f57_0_loop_GT -> f57_0_loop_GT : arg1'=-1+arg1, arg2'=arg2p2, (0 == 0 /\ -1+arg1 < 0), cost: 1 New rule: f57_0_loop_GT -> f57_0_loop_GT : arg1'=-1+arg1, arg2'=arg2p2, -1+arg1 < 0, cost: 1 Propagated Equalities Original rule: f57_0_loop_GT -> f57_0_loop_GT : arg1'=arg1p3, arg2'=arg2p3, (1-arg1p3+arg1 == 0 /\ arg1 > 0), cost: 1 New rule: f57_0_loop_GT -> f57_0_loop_GT : arg1'=1+arg1, arg2'=arg2p3, (0 == 0 /\ arg1 > 0), cost: 1 propagated equality arg1p3 = 1+arg1 Simplified Guard Original rule: f57_0_loop_GT -> f57_0_loop_GT : arg1'=1+arg1, arg2'=arg2p3, (0 == 0 /\ arg1 > 0), cost: 1 New rule: f57_0_loop_GT -> f57_0_loop_GT : arg1'=1+arg1, arg2'=arg2p3, arg1 > 0, cost: 1 Propagated Equalities Original rule: __init -> f57_0_loop_GT : arg1'=arg1p1, arg2'=arg2p1, (1+arg2p4 > 0 /\ arg1p4 > 0 /\ -arg1p1+arg2p4 == 0), cost: 1 New rule: __init -> f57_0_loop_GT : arg1'=arg2p4, arg2'=arg2p1, (0 == 0 /\ 1+arg2p4 > 0 /\ arg1p4 > 0), cost: 1 propagated equality arg1p1 = arg2p4 Simplified Guard Original rule: __init -> f57_0_loop_GT : arg1'=arg2p4, arg2'=arg2p1, (0 == 0 /\ 1+arg2p4 > 0 /\ arg1p4 > 0), cost: 1 New rule: __init -> f57_0_loop_GT : arg1'=arg2p4, arg2'=arg2p1, (1+arg2p4 > 0 /\ arg1p4 > 0), cost: 1 Eliminated Temporary Variables via Transitive Closure Original rule: __init -> f57_0_loop_GT : arg1'=arg2p4, arg2'=arg2p1, (1+arg2p4 > 0 /\ arg1p4 > 0), cost: 1 New rule: __init -> f57_0_loop_GT : arg1'=arg2p4, arg2'=arg2p1, (1+arg2p4 > 0), cost: 1 Step with 7 Trace 7[(1+arg2p4 > 0)] Blocked [{}, {}] Step with 5 Trace 7[(1+arg2p4 > 0)], 5[(-1+arg1 < 0)] Blocked [{}, {}, {}] Nonterm Start location: __init Program variables: arg1 arg2 5: f57_0_loop_GT -> f57_0_loop_GT : arg1'=-1+arg1, arg2'=arg2p2, -1+arg1 < 0, cost: 1 6: f57_0_loop_GT -> f57_0_loop_GT : arg1'=1+arg1, arg2'=arg2p3, arg1 > 0, cost: 1 8: f57_0_loop_GT -> LoAT_sink : (1-arg1 > 0 /\ -1+n >= 0), cost: NONTERM 9: f57_0_loop_GT -> f57_0_loop_GT : arg1'=arg1-n, arg2'=arg2p2, (1-arg1 > 0 /\ -1+n >= 0), cost: 1 7: __init -> f57_0_loop_GT : arg1'=arg2p4, arg2'=arg2p1, (1+arg2p4 > 0), cost: 1 Certificate of Non-Termination Original rule: f57_0_loop_GT -> f57_0_loop_GT : arg1'=-1+arg1, arg2'=arg2p2, (-1+arg1 < 0), cost: 1 New rule: f57_0_loop_GT -> LoAT_sink : (1-arg1 > 0 /\ -1+n >= 0), cost: NONTERM 1-arg1 > 0 [0]: monotonic increase yields 1-arg1 > 0 Replacement map: {1-arg1 > 0 -> 1-arg1 > 0} Loop Acceleration Original rule: f57_0_loop_GT -> f57_0_loop_GT : arg1'=-1+arg1, arg2'=arg2p2, (-1+arg1 < 0), cost: 1 New rule: f57_0_loop_GT -> f57_0_loop_GT : arg1'=arg1-n, arg2'=arg2p2, (1-arg1 > 0 /\ -1+n >= 0), cost: 1 1-arg1 > 0 [0]: monotonic increase yields 1-arg1 > 0 Replacement map: {1-arg1 > 0 -> 1-arg1 > 0} Step with 8 Trace 7[(1+arg2p4 > 0)], 8[(1-arg1 > 0 /\ -1+n >= 0)] Blocked [{}, {}, {8[T]}] Refute Counterexample [ arg1=0 arg2=0 ] 7 [ arg1=arg1 arg2=arg2 ] 8 NO Build SHA: a05f16bf13df659c382799650051f91bf6828c7b