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From: Mikko <mikko.levanto@iki.fi>
Newsgroups: comp.theory
Subject: Re: DD emulated by HHH cannot possibly terminate normally --- x86 code
Date: Sun, 2 Mar 2025 11:48:49 +0200
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On 2025-03-02 01:51:34 +0000, olcott said:

> On 3/1/2025 7:14 PM, Richard Damon wrote:
>> On 3/1/25 6:47 PM, olcott wrote:
>>> On 3/1/2025 2:22 AM, Mikko wrote:
>>>> On 2025-03-01 00:47:58 +0000, olcott said:
>>>> 
>>>>> _DD()
>>>>> [00002133] 55         push ebp      ; housekeeping
>>>>> [00002134] 8bec       mov ebp,esp   ; housekeeping
>>>>> [00002136] 51         push ecx      ; make space for local
>>>>> [00002137] 6833210000 push 00002133 ; push DD
>>>>> [0000213c] e882f4ffff call 000015c3 ; call HHH(DD)
>>>>> [00002141] 83c404     add esp,+04
>>>>> [00002144] 8945fc     mov [ebp-04],eax
>>>>> [00002147] 837dfc00   cmp dword [ebp-04],+00
>>>>> [0000214b] 7402       jz 0000214f
>>>>> [0000214d] ebfe       jmp 0000214d
>>>>> [0000214f] 8b45fc     mov eax,[ebp-04]
>>>>> [00002152] 8be5       mov esp,ebp
>>>>> [00002154] 5d         pop ebp
>>>>> [00002155] c3         ret
>>>>> Size in bytes:(0035) [00002155]
>>>>> 
>>>>> When we hypothesize that the code at machine address
>>>>> 0000213c is an x86 emulator then we know that DD
>>>>> remains stuck in recursive emulation and cannot possibly
>>>>> reach its own "ret" instruction and terminate normally.
>>>> 
>>>> The emulator itself is stuck and cannot return normally but it doesn't
>>>> know it cannot return normally. At some point it runs out of memory
>>>> and terminates normally or abnormally.
>>>> 
>>> 
>>> Yes you are correct about this sub-step of two steps.
>>> 
>>>>> When we add the additional complexity that HHH also
>>>>> aborts this sequence at some point then every level
>>>>> of recursive emulation immediately stops. This does
>>>>> not enable any DD to ever reach its "ret" instruction.
>>>> 
>>>> When we add an additional complexity we must note that there are other
>>>> additional complexities that could be added instead.
>>>> 
>>> 
>>> Sure we could carefully examine every detail about the price
>>> of tea in China.
>>> 
>>> When we are answering the question that seems impossible for
>>> anyone here to pay attention to even when repeated hundreds of times:
>>> 
>>> Can the above DD correctly emulated by HHH possibly
>>> reach its own "ret" instruction and terminate normally?
>> 
>> The problem is that if HHH correctly emulates DD, then it can not answer,
> 
> That is the same stupid shit as saying that no one
> can possibly tell that an infinite loop will ever
> stop running unless they run it and wait until after
> the end of time.

No, it is not. It closer to say that someone cannot possible to tell about
a particular complex loop that it will never stop unless one runs it and
waits until after the end of time.

> Since you are not stupid why do you say such stupid shit?

A truth is a truth even when a fool calls it "shit".

-- 
Mikko