Re: How do simulating termination analyzers work?

On 6/19/2025 1:50 AM, Mikko wrote:

On 2025-06-17 20:34:11 +0000, olcott said:
 

void Infinite_Recursion()
{
   Infinite_Recursion();
   return;
}
>
void Infinite_Loop()
{
   HERE: goto HERE;
   return;
}
>
void DDD()
{
   HHH(DDD);
   return;
}

 Considering the scope of termination analysis the above examples are
extremely simple. The first two are easily seen as non-terminating.
The third example is incomplete as HHH is not given.

*HHH is a simulating termination analyzer*
It simulates its input until it detects
a non halting behavior pattern, then it
aborts and rejects its input.
When it is understood that HHH does simulate itself
simulating DDD then any first year CS student knows
that when each of the above are correctly simulated
by HHH that none of them ever stop running unless aborted.
 > Most C implementations don't even start its execution.
 >

Much of both usefulness and difficulty of termination analysis follows
from termination analyzers ignorance of the input to the program to
be analyzed. The above exmples take no input, except perhaps the last
one where HHH might read some, which significantly simplifies their
analysis.
 

--
Copyright 2025 Olcott "Talent hits a target no one else can hit; Genius
hits a target no one else can see." Arthur Schopenhauer