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From: dbush <dbush.mobile@gmail.com>
Newsgroups: comp.theory
Subject: Re: DD emulated by HHH cannot possibly terminate normally --- x86
 code
Date: Sat, 1 Mar 2025 18:52:11 -0500
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On 3/1/2025 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 answer is dead obviously "no" for everyone that is:
> (a) Technically competent
>    and
> (b) Not deliberately deceptive.

And by the same logic, no_numbers_greater_than_10 correctly emulated by 
F cannot reach its own "ret" instruction, leading to the conclusion that 
there are no natural numbers greater than 10, and you are on record as 
admitting this is correct.