LTS Termination Proof

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Input

Integer Transition System

Proof

1 Invariant Updates

The following invariants are asserted.

0: TRUE
1: TRUE
2: 1 − arg1P ≤ 0 ∧ − arg2P ≤ 0 ∧ 1 − arg1 ≤ 0 ∧ − arg2 ≤ 0
3: 1 − arg1P ≤ 0 ∧ − arg2P ≤ 0 ∧ − arg3P ≤ 0 ∧ 1 − arg1 ≤ 0 ∧ − arg2 ≤ 0 ∧ − arg3 ≤ 0
4: 2 − arg2 ≤ 0
5: 2 − arg2 ≤ 0
6: arg3P ≤ 0 ∧ − arg3P ≤ 0 ∧ 2 − arg2 ≤ 0 ∧ arg3 ≤ 0 ∧ − arg3 ≤ 0 ∧ 1 − x47 ≤ 0
7: TRUE

The invariants are proved as follows.

IMPACT Invariant Proof

2 Switch to Cooperation Termination Proof

We consider the following cutpoint-transitions:
1 15 1: − x47 + x47 ≤ 0 ∧ x47 − x47 ≤ 0 ∧ − x41 + x41 ≤ 0 ∧ x41 − x41 ≤ 0 ∧ − x37 + x37 ≤ 0 ∧ x37 − x37 ≤ 0 ∧ − x19 + x19 ≤ 0 ∧ x19 − x19 ≤ 0 ∧ − x14 + x14 ≤ 0 ∧ x14 − x14 ≤ 0 ∧ − x10 + x10 ≤ 0 ∧ x10 − x10 ≤ 0 ∧ − arg4P + arg4P ≤ 0 ∧ arg4P − arg4P ≤ 0 ∧ − arg4 + arg4 ≤ 0 ∧ arg4 − arg4 ≤ 0 ∧ − arg3P + arg3P ≤ 0 ∧ arg3P − arg3P ≤ 0 ∧ − arg3 + arg3 ≤ 0 ∧ arg3 − arg3 ≤ 0 ∧ − arg2P + arg2P ≤ 0 ∧ arg2P − arg2P ≤ 0 ∧ − arg2 + arg2 ≤ 0 ∧ arg2 − arg2 ≤ 0 ∧ − arg1P + arg1P ≤ 0 ∧ arg1P − arg1P ≤ 0 ∧ − arg1 + arg1 ≤ 0 ∧ arg1 − arg1 ≤ 0
and for every transition t, a duplicate t is considered.

3 Transition Removal

We remove transitions 0, 1, 2, 3, 4, 5, 6, 14 using the following ranking functions, which are bounded by −15.

7: 0
0: 0
2: 0
3: 0
1: 0
4: 0
5: 0
6: 0
7: −6
0: −7
2: −8
3: −9
1: −10
4: −10
5: −10
6: −10
1_var_snapshot: −10
1*: −10

4 Location Addition

The following skip-transition is inserted and corresponding redirections w.r.t. the old location are performed.

1* 18 1: − x47 + x47 ≤ 0 ∧ x47 − x47 ≤ 0 ∧ − x41 + x41 ≤ 0 ∧ x41 − x41 ≤ 0 ∧ − x37 + x37 ≤ 0 ∧ x37 − x37 ≤ 0 ∧ − x19 + x19 ≤ 0 ∧ x19 − x19 ≤ 0 ∧ − x14 + x14 ≤ 0 ∧ x14 − x14 ≤ 0 ∧ − x10 + x10 ≤ 0 ∧ x10 − x10 ≤ 0 ∧ − arg4P + arg4P ≤ 0 ∧ arg4P − arg4P ≤ 0 ∧ − arg4 + arg4 ≤ 0 ∧ arg4 − arg4 ≤ 0 ∧ − arg3P + arg3P ≤ 0 ∧ arg3P − arg3P ≤ 0 ∧ − arg3 + arg3 ≤ 0 ∧ arg3 − arg3 ≤ 0 ∧ − arg2P + arg2P ≤ 0 ∧ arg2P − arg2P ≤ 0 ∧ − arg2 + arg2 ≤ 0 ∧ arg2 − arg2 ≤ 0 ∧ − arg1P + arg1P ≤ 0 ∧ arg1P − arg1P ≤ 0 ∧ − arg1 + arg1 ≤ 0 ∧ arg1 − arg1 ≤ 0

5 Location Addition

The following skip-transition is inserted and corresponding redirections w.r.t. the old location are performed.

1 16 1_var_snapshot: − x47 + x47 ≤ 0 ∧ x47 − x47 ≤ 0 ∧ − x41 + x41 ≤ 0 ∧ x41 − x41 ≤ 0 ∧ − x37 + x37 ≤ 0 ∧ x37 − x37 ≤ 0 ∧ − x19 + x19 ≤ 0 ∧ x19 − x19 ≤ 0 ∧ − x14 + x14 ≤ 0 ∧ x14 − x14 ≤ 0 ∧ − x10 + x10 ≤ 0 ∧ x10 − x10 ≤ 0 ∧ − arg4P + arg4P ≤ 0 ∧ arg4P − arg4P ≤ 0 ∧ − arg4 + arg4 ≤ 0 ∧ arg4 − arg4 ≤ 0 ∧ − arg3P + arg3P ≤ 0 ∧ arg3P − arg3P ≤ 0 ∧ − arg3 + arg3 ≤ 0 ∧ arg3 − arg3 ≤ 0 ∧ − arg2P + arg2P ≤ 0 ∧ arg2P − arg2P ≤ 0 ∧ − arg2 + arg2 ≤ 0 ∧ arg2 − arg2 ≤ 0 ∧ − arg1P + arg1P ≤ 0 ∧ arg1P − arg1P ≤ 0 ∧ − arg1 + arg1 ≤ 0 ∧ arg1 − arg1 ≤ 0

6 SCC Decomposition

We consider subproblems for each of the 1 SCC(s) of the program graph.

6.1 SCC Subproblem 1/1

Here we consider the SCC { 1, 4, 5, 6, 1_var_snapshot, 1* }.

6.1.1 Transition Removal

We remove transitions 7, 8, 9, 10, 11, 12, 13 using the following ranking functions, which are bounded by 14.

1: 5 + 8⋅arg2
4: 3 + 8⋅arg2
5: 8⋅arg2 + 2⋅arg3
6: −1 + 8⋅arg2
1_var_snapshot: 4 + 8⋅arg2
1*: 6 + 8⋅arg2

6.1.2 Transition Removal

We remove transitions 16, 18 using the following ranking functions, which are bounded by −2.

1: −1
4: 0
5: 0
6: 0
1_var_snapshot: −2
1*: 0

6.1.3 Splitting Cut-Point Transitions

We consider 1 subproblems corresponding to sets of cut-point transitions as follows.

6.1.3.1 Cut-Point Subproblem 1/1

Here we consider cut-point transition 15.

6.1.3.1.1 Splitting Cut-Point Transitions

There remain no cut-point transition to consider. Hence the cooperation termination is trivial.

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