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From: "Fred. Zwarts" <F.Zwarts@HetNet.nl>
Newsgroups: comp.theory
Subject: Re: DD emulated by HHH cannot possibly terminate normally --- x86
 code
Date: Sat, 1 Mar 2025 11:44:15 +0100
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Op 01.mrt.2025 om 01:47 schreef olcott:
> _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.
> 
> 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.
> 

Again the same claim. No progress. Why? Is there anybody claiming that 
HHH does reach the 'ret' instruction?
We all agree that HHH fails to reach the 'ret' instruction of the finite 
string that, when given for direct execution has no problem to reach the 
'ret' instruction. What does this failure of HHH mean? What is the next 
step? To me it seems to be more evidence for the halting theorem.