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: TRUE
3: TRUE
4: TRUE
5: TRUE
6: TRUE
7: TRUE
8: b_0 ≤ 0
9: TRUE
10: TRUE

The invariants are proved as follows.

IMPACT Invariant Proof

2 Switch to Cooperation Termination Proof

We consider the following cutpoint-transitions:
2 15 2: tmp_post + tmp_post ≤ 0tmp_posttmp_post ≤ 0tmp_0 + tmp_0 ≤ 0tmp_0tmp_0 ≤ 0n_post + n_post ≤ 0n_postn_post ≤ 0n_0 + n_0 ≤ 0n_0n_0 ≤ 0j_post + j_post ≤ 0j_postj_post ≤ 0j_0 + j_0 ≤ 0j_0j_0 ≤ 0i_post + i_post ≤ 0i_posti_post ≤ 0i_0 + i_0 ≤ 0i_0i_0 ≤ 0b_0 + b_0 ≤ 0b_0b_0 ≤ 0___const_1023_0 + ___const_1023_0 ≤ 0___const_1023_0___const_1023_0 ≤ 0
and for every transition t, a duplicate t is considered.

3 Transition Removal

We remove transitions 0, 2, 3, 4, 5, 6, 8, 9, 10, 11, 12, 13, 14 using the following ranking functions, which are bounded by −25.

10: 0
9: 0
5: 0
4: 0
3: 0
0: 0
2: 0
1: 0
8: 0
6: 0
7: 0
10: −11
9: −12
5: −13
4: −14
3: −15
0: −16
2: −16
2_var_snapshot: −16
2*: −16
1: −17
8: −18
6: −19
7: −20

4 Location Addition

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

2* 18 2: tmp_post + tmp_post ≤ 0tmp_posttmp_post ≤ 0tmp_0 + tmp_0 ≤ 0tmp_0tmp_0 ≤ 0n_post + n_post ≤ 0n_postn_post ≤ 0n_0 + n_0 ≤ 0n_0n_0 ≤ 0j_post + j_post ≤ 0j_postj_post ≤ 0j_0 + j_0 ≤ 0j_0j_0 ≤ 0i_post + i_post ≤ 0i_posti_post ≤ 0i_0 + i_0 ≤ 0i_0i_0 ≤ 0b_0 + b_0 ≤ 0b_0b_0 ≤ 0___const_1023_0 + ___const_1023_0 ≤ 0___const_1023_0___const_1023_0 ≤ 0

5 Location Addition

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

2 16 2_var_snapshot: tmp_post + tmp_post ≤ 0tmp_posttmp_post ≤ 0tmp_0 + tmp_0 ≤ 0tmp_0tmp_0 ≤ 0n_post + n_post ≤ 0n_postn_post ≤ 0n_0 + n_0 ≤ 0n_0n_0 ≤ 0j_post + j_post ≤ 0j_postj_post ≤ 0j_0 + j_0 ≤ 0j_0j_0 ≤ 0i_post + i_post ≤ 0i_posti_post ≤ 0i_0 + i_0 ≤ 0i_0i_0 ≤ 0b_0 + b_0 ≤ 0b_0b_0 ≤ 0___const_1023_0 + ___const_1023_0 ≤ 0___const_1023_0___const_1023_0 ≤ 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 { 0, 2, 2_var_snapshot, 2* }.

6.1.1 Transition Removal

We remove transition 1 using the following ranking functions, which are bounded by −2.

0: −1 − 4⋅i_0 + 4⋅n_0
2: 1 − 4⋅i_0 + 4⋅n_0
2_var_snapshot: −4⋅i_0 + 4⋅n_0
2*: 2 − 4⋅i_0 + 4⋅n_0

6.1.2 Transition Removal

We remove transitions 16, 18 using the following ranking functions, which are bounded by −1.

0: −2
2: 0
2_var_snapshot: −1
2*: 1

6.1.3 Transition Removal

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

0: −1
2: 0
2_var_snapshot: 0
2*: 0

6.1.4 Splitting Cut-Point Transitions

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

6.1.4.1 Cut-Point Subproblem 1/1

Here we consider cut-point transition 15.

6.1.4.1.1 Splitting Cut-Point Transitions

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

Tool configuration

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