LTS Termination Proof

by T2Cert

Input

Integer Transition System

Proof

1 Invariant Updates

The following invariants are asserted.

0: TRUE
1: arg1P ≤ 0arg1 ≤ 0
2: TRUE
3: arg6 ≤ 0arg7 ≤ 0
4: x41 ≤ 0x40 ≤ 0
5: TRUE

The invariants are proved as follows.

IMPACT Invariant Proof

2 Switch to Cooperation Termination Proof

We consider the following cutpoint-transitions:
2 10 2: x94 + x94 ≤ 0x94x94 ≤ 0x93 + x93 ≤ 0x93x93 ≤ 0x81 + x81 ≤ 0x81x81 ≤ 0x80 + x80 ≤ 0x80x80 ≤ 0x79 + x79 ≤ 0x79x79 ≤ 0x78 + x78 ≤ 0x78x78 ≤ 0x77 + x77 ≤ 0x77x77 ≤ 0x69 + x69 ≤ 0x69x69 ≤ 0x68 + x68 ≤ 0x68x68 ≤ 0x67 + x67 ≤ 0x67x67 ≤ 0x54 + x54 ≤ 0x54x54 ≤ 0x53 + x53 ≤ 0x53x53 ≤ 0x52 + x52 ≤ 0x52x52 ≤ 0x51 + x51 ≤ 0x51x51 ≤ 0x50 + x50 ≤ 0x50x50 ≤ 0x5 + x5 ≤ 0x5x5 ≤ 0x49 + x49 ≤ 0x49x49 ≤ 0x48 + x48 ≤ 0x48x48 ≤ 0x41 + x41 ≤ 0x41x41 ≤ 0x40 + x40 ≤ 0x40x40 ≤ 0x4 + x4 ≤ 0x4x4 ≤ 0x10 + x10 ≤ 0x10x10 ≤ 0arg7P + arg7P ≤ 0arg7Parg7P ≤ 0arg7 + arg7 ≤ 0arg7arg7 ≤ 0arg6P + arg6P ≤ 0arg6Parg6P ≤ 0arg6 + arg6 ≤ 0arg6arg6 ≤ 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
4 17 4: x94 + x94 ≤ 0x94x94 ≤ 0x93 + x93 ≤ 0x93x93 ≤ 0x81 + x81 ≤ 0x81x81 ≤ 0x80 + x80 ≤ 0x80x80 ≤ 0x79 + x79 ≤ 0x79x79 ≤ 0x78 + x78 ≤ 0x78x78 ≤ 0x77 + x77 ≤ 0x77x77 ≤ 0x69 + x69 ≤ 0x69x69 ≤ 0x68 + x68 ≤ 0x68x68 ≤ 0x67 + x67 ≤ 0x67x67 ≤ 0x54 + x54 ≤ 0x54x54 ≤ 0x53 + x53 ≤ 0x53x53 ≤ 0x52 + x52 ≤ 0x52x52 ≤ 0x51 + x51 ≤ 0x51x51 ≤ 0x50 + x50 ≤ 0x50x50 ≤ 0x5 + x5 ≤ 0x5x5 ≤ 0x49 + x49 ≤ 0x49x49 ≤ 0x48 + x48 ≤ 0x48x48 ≤ 0x41 + x41 ≤ 0x41x41 ≤ 0x40 + x40 ≤ 0x40x40 ≤ 0x4 + x4 ≤ 0x4x4 ≤ 0x10 + x10 ≤ 0x10x10 ≤ 0arg7P + arg7P ≤ 0arg7Parg7P ≤ 0arg7 + arg7 ≤ 0arg7arg7 ≤ 0arg6P + arg6P ≤ 0arg6Parg6P ≤ 0arg6 + arg6 ≤ 0arg6arg6 ≤ 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, 1, 2, 7, 9 using the following ranking functions, which are bounded by −17.

5: 0
0: 0
1: 0
2: 0
3: 0
4: 0
5: −6
0: −7
1: −8
2: −9
3: −9
2_var_snapshot: −9
2*: −9
4: −12
4_var_snapshot: −12
4*: −12

4 Location Addition

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

2* 13 2: x94 + x94 ≤ 0x94x94 ≤ 0x93 + x93 ≤ 0x93x93 ≤ 0x81 + x81 ≤ 0x81x81 ≤ 0x80 + x80 ≤ 0x80x80 ≤ 0x79 + x79 ≤ 0x79x79 ≤ 0x78 + x78 ≤ 0x78x78 ≤ 0x77 + x77 ≤ 0x77x77 ≤ 0x69 + x69 ≤ 0x69x69 ≤ 0x68 + x68 ≤ 0x68x68 ≤ 0x67 + x67 ≤ 0x67x67 ≤ 0x54 + x54 ≤ 0x54x54 ≤ 0x53 + x53 ≤ 0x53x53 ≤ 0x52 + x52 ≤ 0x52x52 ≤ 0x51 + x51 ≤ 0x51x51 ≤ 0x50 + x50 ≤ 0x50x50 ≤ 0x5 + x5 ≤ 0x5x5 ≤ 0x49 + x49 ≤ 0x49x49 ≤ 0x48 + x48 ≤ 0x48x48 ≤ 0x41 + x41 ≤ 0x41x41 ≤ 0x40 + x40 ≤ 0x40x40 ≤ 0x4 + x4 ≤ 0x4x4 ≤ 0x10 + x10 ≤ 0x10x10 ≤ 0arg7P + arg7P ≤ 0arg7Parg7P ≤ 0arg7 + arg7 ≤ 0arg7arg7 ≤ 0arg6P + arg6P ≤ 0arg6Parg6P ≤ 0arg6 + arg6 ≤ 0arg6arg6 ≤ 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.

2 11 2_var_snapshot: x94 + x94 ≤ 0x94x94 ≤ 0x93 + x93 ≤ 0x93x93 ≤ 0x81 + x81 ≤ 0x81x81 ≤ 0x80 + x80 ≤ 0x80x80 ≤ 0x79 + x79 ≤ 0x79x79 ≤ 0x78 + x78 ≤ 0x78x78 ≤ 0x77 + x77 ≤ 0x77x77 ≤ 0x69 + x69 ≤ 0x69x69 ≤ 0x68 + x68 ≤ 0x68x68 ≤ 0x67 + x67 ≤ 0x67x67 ≤ 0x54 + x54 ≤ 0x54x54 ≤ 0x53 + x53 ≤ 0x53x53 ≤ 0x52 + x52 ≤ 0x52x52 ≤ 0x51 + x51 ≤ 0x51x51 ≤ 0x50 + x50 ≤ 0x50x50 ≤ 0x5 + x5 ≤ 0x5x5 ≤ 0x49 + x49 ≤ 0x49x49 ≤ 0x48 + x48 ≤ 0x48x48 ≤ 0x41 + x41 ≤ 0x41x41 ≤ 0x40 + x40 ≤ 0x40x40 ≤ 0x4 + x4 ≤ 0x4x4 ≤ 0x10 + x10 ≤ 0x10x10 ≤ 0arg7P + arg7P ≤ 0arg7Parg7P ≤ 0arg7 + arg7 ≤ 0arg7arg7 ≤ 0arg6P + arg6P ≤ 0arg6Parg6P ≤ 0arg6 + arg6 ≤ 0arg6arg6 ≤ 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.

4* 20 4: x94 + x94 ≤ 0x94x94 ≤ 0x93 + x93 ≤ 0x93x93 ≤ 0x81 + x81 ≤ 0x81x81 ≤ 0x80 + x80 ≤ 0x80x80 ≤ 0x79 + x79 ≤ 0x79x79 ≤ 0x78 + x78 ≤ 0x78x78 ≤ 0x77 + x77 ≤ 0x77x77 ≤ 0x69 + x69 ≤ 0x69x69 ≤ 0x68 + x68 ≤ 0x68x68 ≤ 0x67 + x67 ≤ 0x67x67 ≤ 0x54 + x54 ≤ 0x54x54 ≤ 0x53 + x53 ≤ 0x53x53 ≤ 0x52 + x52 ≤ 0x52x52 ≤ 0x51 + x51 ≤ 0x51x51 ≤ 0x50 + x50 ≤ 0x50x50 ≤ 0x5 + x5 ≤ 0x5x5 ≤ 0x49 + x49 ≤ 0x49x49 ≤ 0x48 + x48 ≤ 0x48x48 ≤ 0x41 + x41 ≤ 0x41x41 ≤ 0x40 + x40 ≤ 0x40x40 ≤ 0x4 + x4 ≤ 0x4x4 ≤ 0x10 + x10 ≤ 0x10x10 ≤ 0arg7P + arg7P ≤ 0arg7Parg7P ≤ 0arg7 + arg7 ≤ 0arg7arg7 ≤ 0arg6P + arg6P ≤ 0arg6Parg6P ≤ 0arg6 + arg6 ≤ 0arg6arg6 ≤ 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.

4 18 4_var_snapshot: x94 + x94 ≤ 0x94x94 ≤ 0x93 + x93 ≤ 0x93x93 ≤ 0x81 + x81 ≤ 0x81x81 ≤ 0x80 + x80 ≤ 0x80x80 ≤ 0x79 + x79 ≤ 0x79x79 ≤ 0x78 + x78 ≤ 0x78x78 ≤ 0x77 + x77 ≤ 0x77x77 ≤ 0x69 + x69 ≤ 0x69x69 ≤ 0x68 + x68 ≤ 0x68x68 ≤ 0x67 + x67 ≤ 0x67x67 ≤ 0x54 + x54 ≤ 0x54x54 ≤ 0x53 + x53 ≤ 0x53x53 ≤ 0x52 + x52 ≤ 0x52x52 ≤ 0x51 + x51 ≤ 0x51x51 ≤ 0x50 + x50 ≤ 0x50x50 ≤ 0x5 + x5 ≤ 0x5x5 ≤ 0x49 + x49 ≤ 0x49x49 ≤ 0x48 + x48 ≤ 0x48x48 ≤ 0x41 + x41 ≤ 0x41x41 ≤ 0x40 + x40 ≤ 0x40x40 ≤ 0x4 + x4 ≤ 0x4x4 ≤ 0x10 + x10 ≤ 0x10x10 ≤ 0arg7P + arg7P ≤ 0arg7Parg7P ≤ 0arg7 + arg7 ≤ 0arg7arg7 ≤ 0arg6P + arg6P ≤ 0arg6Parg6P ≤ 0arg6 + arg6 ≤ 0arg6arg6 ≤ 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 2 SCC(s) of the program graph.

8.1 SCC Subproblem 1/2

Here we consider the SCC { 2, 3, 2_var_snapshot, 2* }.

8.1.1 Transition Removal

We remove transitions 3, 4, 6 using the following ranking functions, which are bounded by 3.

2: 2 + 4⋅arg4
3: 4⋅arg4
2_var_snapshot: 1 + 4⋅arg4
2*: 3 + 4⋅arg4

8.1.2 Transition Removal

We remove transitions 11, 13, 5 using the following ranking functions, which are bounded by −3.

2: −1
3: −3
2_var_snapshot: −2
2*: 0

8.1.3 Splitting Cut-Point Transitions

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

8.1.3.1 Cut-Point Subproblem 1/1

Here we consider cut-point transition 10.

8.1.3.1.1 Splitting Cut-Point Transitions

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

8.2 SCC Subproblem 2/2

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

8.2.1 Transition Removal

We remove transition 8 using the following ranking functions, which are bounded by 2.

4: 1 + 3⋅arg1
4_var_snapshot: 3⋅arg1
4*: 2 + 3⋅arg1

8.2.2 Transition Removal

We remove transitions 18, 20 using the following ranking functions, which are bounded by −2.

4: −1
4_var_snapshot: −2
4*: 0

8.2.3 Splitting Cut-Point Transitions

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

8.2.3.1 Cut-Point Subproblem 1/1

Here we consider cut-point transition 17.

8.2.3.1.1 Splitting Cut-Point Transitions

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

Tool configuration

T2Cert