LTS Termination Proof

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Input

Integer Transition System

Proof

1 Invariant Updates

The following invariants are asserted.

0: TRUE
1: arg1P ≤ 0arg2P ≤ 0arg1 ≤ 0arg2 ≤ 0
2: arg1 ≤ 0arg2 ≤ 01 − arg3 ≤ 0
3: 1 − arg3P ≤ 01 − arg4P ≤ 01 − arg3 ≤ 01 − arg4 ≤ 0
4: 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: x33 + x33 ≤ 0x33x33 ≤ 0x32 + x32 ≤ 0x32x32 ≤ 0x22 + x22 ≤ 0x22x22 ≤ 0x21 + x21 ≤ 0x21x21 ≤ 0x12 + x12 ≤ 0x12x12 ≤ 0x11 + x11 ≤ 0x11x11 ≤ 0arg8P + arg8P ≤ 0arg8Parg8P ≤ 0arg8 + arg8 ≤ 0arg8arg8 ≤ 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, 8 using the following ranking functions, which are bounded by −11.

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

4 Location Addition

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

1* 12 1: x33 + x33 ≤ 0x33x33 ≤ 0x32 + x32 ≤ 0x32x32 ≤ 0x22 + x22 ≤ 0x22x22 ≤ 0x21 + x21 ≤ 0x21x21 ≤ 0x12 + x12 ≤ 0x12x12 ≤ 0x11 + x11 ≤ 0x11x11 ≤ 0arg8P + arg8P ≤ 0arg8Parg8P ≤ 0arg8 + arg8 ≤ 0arg8arg8 ≤ 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.

1 10 1_var_snapshot: x33 + x33 ≤ 0x33x33 ≤ 0x32 + x32 ≤ 0x32x32 ≤ 0x22 + x22 ≤ 0x22x22 ≤ 0x21 + x21 ≤ 0x21x21 ≤ 0x12 + x12 ≤ 0x12x12 ≤ 0x11 + x11 ≤ 0x11x11 ≤ 0arg8P + arg8P ≤ 0arg8Parg8P ≤ 0arg8 + arg8 ≤ 0arg8arg8 ≤ 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 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, 2, 3, 1_var_snapshot, 1* }.

6.1.1 Transition Removal

We remove transitions 1, 2, 3, 4, 5, 6, 7 using the following ranking functions, which are bounded by 5.

1: 3 + 6⋅arg3
2: 1 + 6⋅arg3
3: 6⋅arg1
1_var_snapshot: 2 + 6⋅arg3
1*: 4 + 6⋅arg3

6.1.2 Transition Removal

We remove transition 12 using the following ranking functions, which are bounded by −1.

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

6.1.3 Transition Removal

We remove transition 10 using the following ranking functions, which are bounded by 0.

1: 1
2: 0
3: 0
1_var_snapshot: 0
1*: 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 9.

6.1.4.1.1 Splitting Cut-Point Transitions

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

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