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: arg3P ≤ 0arg3 ≤ 0
3: TRUE

The invariants are proved as follows.

IMPACT Invariant Proof

2 Switch to Cooperation Termination Proof

We consider the following cutpoint-transitions:
1 9 1: x37 + x37 ≤ 0x37x37 ≤ 0x36 + x36 ≤ 0x36x36 ≤ 0x30 + x30 ≤ 0x30x30 ≤ 0x29 + x29 ≤ 0x29x29 ≤ 0arg5P + arg5P ≤ 0arg5Parg5P ≤ 0arg5 + arg5 ≤ 0arg5arg5 ≤ 0arg4P + arg4P ≤ 0arg4Parg4P ≤ 0arg4 + arg4 ≤ 0arg4arg4 ≤ 0arg3P + arg3P ≤ 0arg3Parg3P ≤ 0arg3 + arg3 ≤ 0arg3arg3 ≤ 0arg2P + arg2P ≤ 0arg2Parg2P ≤ 0arg2 + arg2 ≤ 0arg2arg2 ≤ 0arg1P + arg1P ≤ 0arg1Parg1P ≤ 0arg1 + arg1 ≤ 0arg1arg1 ≤ 0
2 16 2: x37 + x37 ≤ 0x37x37 ≤ 0x36 + x36 ≤ 0x36x36 ≤ 0x30 + x30 ≤ 0x30x30 ≤ 0x29 + x29 ≤ 0x29x29 ≤ 0arg5P + arg5P ≤ 0arg5Parg5P ≤ 0arg5 + arg5 ≤ 0arg5arg5 ≤ 0arg4P + arg4P ≤ 0arg4Parg4P ≤ 0arg4 + arg4 ≤ 0arg4arg4 ≤ 0arg3P + arg3P ≤ 0arg3Parg3P ≤ 0arg3 + arg3 ≤ 0arg3arg3 ≤ 0arg2P + arg2P ≤ 0arg2Parg2P ≤ 0arg2 + arg2 ≤ 0arg2arg2 ≤ 0arg1P + arg1P ≤ 0arg1Parg1P ≤ 0arg1 + arg1 ≤ 0arg1arg1 ≤ 0
and for every transition t, a duplicate t is considered.

3 Transition Removal

We remove transitions 0, 8 using the following ranking functions, which are bounded by −13.

3: 0
0: 0
1: 0
2: 0
3: −4
0: −5
1: −6
2: −6
1_var_snapshot: −6
1*: −6
2_var_snapshot: −6
2*: −6

4 Location Addition

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

1* 12 1: x37 + x37 ≤ 0x37x37 ≤ 0x36 + x36 ≤ 0x36x36 ≤ 0x30 + x30 ≤ 0x30x30 ≤ 0x29 + x29 ≤ 0x29x29 ≤ 0arg5P + arg5P ≤ 0arg5Parg5P ≤ 0arg5 + arg5 ≤ 0arg5arg5 ≤ 0arg4P + arg4P ≤ 0arg4Parg4P ≤ 0arg4 + arg4 ≤ 0arg4arg4 ≤ 0arg3P + arg3P ≤ 0arg3Parg3P ≤ 0arg3 + arg3 ≤ 0arg3arg3 ≤ 0arg2P + arg2P ≤ 0arg2Parg2P ≤ 0arg2 + arg2 ≤ 0arg2arg2 ≤ 0arg1P + arg1P ≤ 0arg1Parg1P ≤ 0arg1 + arg1 ≤ 0arg1arg1 ≤ 0

5 Location Addition

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

1 10 1_var_snapshot: x37 + x37 ≤ 0x37x37 ≤ 0x36 + x36 ≤ 0x36x36 ≤ 0x30 + x30 ≤ 0x30x30 ≤ 0x29 + x29 ≤ 0x29x29 ≤ 0arg5P + arg5P ≤ 0arg5Parg5P ≤ 0arg5 + arg5 ≤ 0arg5arg5 ≤ 0arg4P + arg4P ≤ 0arg4Parg4P ≤ 0arg4 + arg4 ≤ 0arg4arg4 ≤ 0arg3P + arg3P ≤ 0arg3Parg3P ≤ 0arg3 + arg3 ≤ 0arg3arg3 ≤ 0arg2P + arg2P ≤ 0arg2Parg2P ≤ 0arg2 + arg2 ≤ 0arg2arg2 ≤ 0arg1P + arg1P ≤ 0arg1Parg1P ≤ 0arg1 + arg1 ≤ 0arg1arg1 ≤ 0

6 Location Addition

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

2* 19 2: x37 + x37 ≤ 0x37x37 ≤ 0x36 + x36 ≤ 0x36x36 ≤ 0x30 + x30 ≤ 0x30x30 ≤ 0x29 + x29 ≤ 0x29x29 ≤ 0arg5P + arg5P ≤ 0arg5Parg5P ≤ 0arg5 + arg5 ≤ 0arg5arg5 ≤ 0arg4P + arg4P ≤ 0arg4Parg4P ≤ 0arg4 + arg4 ≤ 0arg4arg4 ≤ 0arg3P + arg3P ≤ 0arg3Parg3P ≤ 0arg3 + arg3 ≤ 0arg3arg3 ≤ 0arg2P + arg2P ≤ 0arg2Parg2P ≤ 0arg2 + arg2 ≤ 0arg2arg2 ≤ 0arg1P + arg1P ≤ 0arg1Parg1P ≤ 0arg1 + arg1 ≤ 0arg1arg1 ≤ 0

7 Location Addition

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

2 17 2_var_snapshot: x37 + x37 ≤ 0x37x37 ≤ 0x36 + x36 ≤ 0x36x36 ≤ 0x30 + x30 ≤ 0x30x30 ≤ 0x29 + x29 ≤ 0x29x29 ≤ 0arg5P + arg5P ≤ 0arg5Parg5P ≤ 0arg5 + arg5 ≤ 0arg5arg5 ≤ 0arg4P + arg4P ≤ 0arg4Parg4P ≤ 0arg4 + arg4 ≤ 0arg4arg4 ≤ 0arg3P + arg3P ≤ 0arg3Parg3P ≤ 0arg3 + arg3 ≤ 0arg3arg3 ≤ 0arg2P + arg2P ≤ 0arg2Parg2P ≤ 0arg2 + arg2 ≤ 0arg2arg2 ≤ 0arg1P + arg1P ≤ 0arg1Parg1P ≤ 0arg1 + arg1 ≤ 0arg1arg1 ≤ 0

8 SCC Decomposition

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

8.1 SCC Subproblem 1/1

Here we consider the SCC { 1, 2, 1_var_snapshot, 1*, 2_var_snapshot, 2* }.

8.1.1 Transition Removal

We remove transitions 1, 6, 7 using the following ranking functions, which are bounded by −153.

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

8.1.2 Transition Removal

We remove transitions 10, 12, 2, 3 using the following ranking functions, which are bounded by −3.

1: −2
2: 0
1_var_snapshot: −3
1*: −1
2_var_snapshot: 0
2*: 0

8.1.3 Transition Removal

We remove transitions 4, 5 using the following ranking functions, which are bounded by −77.

1: 0
2: 1 − 3⋅arg4arg5
1_var_snapshot: 0
1*: 0
2_var_snapshot: −3⋅arg4arg5
2*: 2 − 3⋅arg4arg5

8.1.4 Transition Removal

We remove transition 17 using the following ranking functions, which are bounded by −1.

1: 0
2: 0
1_var_snapshot: 0
1*: 0
2_var_snapshot: −1
2*: 1

8.1.5 Transition Removal

We remove transition 19 using the following ranking functions, which are bounded by −1.

1: 0
2: −1
1_var_snapshot: 0
1*: 0
2_var_snapshot: 0
2*: 0

8.1.6 Splitting Cut-Point Transitions

We consider 2 subproblems corresponding to sets of cut-point transitions as follows.

8.1.6.1 Cut-Point Subproblem 1/2

Here we consider cut-point transition 9.

8.1.6.1.1 Splitting Cut-Point Transitions

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

8.1.6.2 Cut-Point Subproblem 2/2

Here we consider cut-point transition 16.

8.1.6.2.1 Splitting Cut-Point Transitions

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

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