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From: Mikko <mikko.levanto@iki.fi>
Newsgroups: comp.theory
Subject: Re: The actual code of HHH
Date: Fri, 28 Feb 2025 11:16:53 +0200
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On 2025-02-27 15:29:31 +0000, olcott said:

> On 2/27/2025 3:26 AM, Fred. Zwarts wrote:
>> Op 27.feb.2025 om 00:09 schreef olcott:
>>> On 2/26/2025 3:52 PM, joes wrote:
>>>> Since there is so much talk around, but not really about it,
>>>> let's take a look:
>>>> https://github.com/plolcott/x86utm/blob/
>>>> 48b4cbfeb3f486507276a5fc4e9b10875ab24dbf/Halt7.c#L1081
>>>> In line 1137, we compute a flag:
>>>> u32 Root = Init_Halts_HH(&Aborted, &execution_trace, &decoded, &code_end,
>>>> (u32)P, &master_state, &slave_state, &slave_stack);
>>>> In line 918, we find it basically checks for the magic number
>>>> **execution_trace==0x90909090. What is this unexplained value?
>>>> 
>>>> We then pass the saved flag in line 1143:
>>>> if (Decide_Halting_HH(&Aborted, &execution_trace, &decoded,
>>>> code_end, End_Of_Code, &master_state, &slave_state, &slave_stack, Root)),
>>>> defined in line 1030.
>>>> Then we get a switch:
>>>> 1059    if (Root)  // Master UTM halt decider
>>>> Line 1070 is then conditionally skipped:
>>>> Needs_To_Be_Aborted_HH((Decoded_Line_Of_Code*)**execution_trace);
>>>> defined in line 1012, which (on a jmp or call instruction) calls
>>>> u32 Needs_To_Be_Aborted_Trace_HH(Decoded_Line_Of_Code* execution_trace,
>>>>                                   Decoded_Line_Of_Code *current)
>>>> in line 964, where the abort logic lives. (It basically triggers
>>>> on a call or jump to itself.)
>>>> 
>>>> So we only abort depending on the address of the execution trace.
>>>> This makes no sense. Why is that?
>>>> 
>>> 
>>> DD emulated by HHH according to the behavior that the x86
>>> machine code of DD cannot possibly terminate normally thus
>>> HHH is infallibly correct to report that this DD emulated
>>> by HHH (not any other DD in the whole freaking universe)
>>> is not-terminating.
>> No, it is correct to report that HHH is unable to correctly simulate 
>> this halting program up to its end.
> 
> In other words you are totally clueless that infinite
> recursion HAS NO END.

Do you mean that having no end enables the simulation to the end?

-- 
Mikko