Path: ...!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!eternal-september.org!.POSTED!not-for-mail
From: Mikko <mikko.levanto@iki.fi>
Newsgroups: comp.theory
Subject: Re: DDD specifies recursive emulation to HHH and halting to HHH1
Date: Tue, 1 Apr 2025 09:25:55 +0300
Organization: -
Lines: 78
Message-ID: <vsg0tj$2e09c$1@dont-email.me>
References: <vrfuob$256og$1@dont-email.me> <vs6srk$39556$12@dont-email.me> <vs6t10$2p360$6@dont-email.me> <vs70tc$39556$21@dont-email.me> <vs71bq$2p360$10@dont-email.me> <vs76m9$3m3q0$1@dont-email.me> <vs77th$2p360$11@dont-email.me> <vs78cu$3ms9k$1@dont-email.me> <c2b91231b9052e07b6705250938fb9095e711327@i2pn2.org> <vs7kvf$3eal$2@dont-email.me> <aeb75b411e9f77c974585181c671a47d03b22078@i2pn2.org> <vs7qdm$8dae$2@dont-email.me> <vs7r9b$8ajp$1@dont-email.me> <vs92l3$1fccq$5@dont-email.me> <vs93ae$1k9u2$1@dont-email.me> <vs9g5p$1v2n9$5@dont-email.me> <vs9gcg$20g2j$3@dont-email.me> <vs9h9o$23cav$2@dont-email.me> <vs9hh3$20g2j$6@dont-email.me> <vs9jie$23cav$4@dont-email.me> <vs9kb1$26cg5$2@dont-email.me> <vs9pni$27rl4$9@dont-email.me> <3ade9e84224ba9b99c7363e0e9b69181804b7daa@i2pn2.org> <vsc2fd$1vihj$2@dont-email.me> <e1da7d564873d36f88e119fbbbdafd8c6b0f675e@i2pn2.org> <vsc9o7$2bk3d$2@dont-email.me> <vsdkq5$3rdgv$1@dont-email.me> <vselj9$th5g$1@dont-email.me>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Transfer-Encoding: 8bit
Injection-Date: Tue, 01 Apr 2025 08:25:56 +0200 (CEST)
Injection-Info: dont-email.me; posting-host="7e55fdc1b890aa9fa8cb01c299796346";
	logging-data="2556204"; mail-complaints-to="abuse@eternal-september.org";	posting-account="U2FsdGVkX1/ZQuiIVQltTdWKs7Ea27gN"
User-Agent: Unison/2.2
Cancel-Lock: sha1:8cFUiBOKev/wASAnRoRx3A/XdIE=
Bytes: 4923

On 2025-03-31 18:06:35 +0000, olcott said:

> On 3/31/2025 3:47 AM, Mikko wrote:
>> On 2025-03-30 20:32:07 +0000, olcott said:
>> 
>>> On 3/30/2025 1:52 PM, Richard Damon wrote:
>>>> On 3/30/25 2:27 PM, olcott wrote:
>>>>> On 3/30/2025 3:12 AM, joes wrote:
>>>>>> Am Sat, 29 Mar 2025 16:46:26 -0500 schrieb olcott:
>>>>>>> On 3/29/2025 3:14 PM, dbush wrote:
>>>>>>>> On 3/29/2025 4:01 PM, olcott wrote:
>>>>>> 
>>>>>>>>> We can know that when this adapted UTM simulates a finite number of
>>>>>>>>> steps of its input that this finite number of steps were simulated
>>>>>>>>> correctly.
>>>>>>>> And therefore does not do a correct UTM simulation that matches the
>>>>>>>> behavior of the direct execution as it is incomplete.
>>>>>>> It is dishonest to expect non-terminating inputs to complete.
>>>>>> A complete simulation of a nonterminating input doesn't halt.
>>>>>> 
>>>>>>>>>> 2) changing the input is not allowed
>>>>>>>>> The input is unchanged. There never was any indication that the input
>>>>>>>>> was in any way changed.
>>>>>>>> False, if the starting function calls UTM and UTM changes, you're
>>>>>>>> changing the input.
>>>>>>> When UTM1 is a UTM that has been adapted to only simulate a finite
>>>>>>> number of steps
>>>>>> So not an UTM.
>>>>>> 
>>>>>>> and input D calls UTM1 then the behavior of D simulated
>>>>>>> by UTM1 never reaches its final halt state.
>>>>>>> When D is simulated by ordinary UTM2 that D does not call Then D reaches
>>>>>>> its final halt state.
>>>>>> Doesn't matter if it calls it, but if the UTM halts.
>>>>>> 
>>>>>>>> Changing the input is not allowed.
>>>>>>> I never changed the input. D always calls UTM1.
>>>>>>> thus is the same input to UTM1 as it is to UTM2.
>>>>>> You changed UTM1, which is part of the input D.
>>>>>> 
>>>>> 
>>>>> UTM1 simulates D that calls UTM1
>>>>> simulated D NEVER reaches final halt state
>>>>> 
>>>>> UTM2 simulates D that calls UTM1
>>>>> simulated D ALWAYS reaches final halt state
>>>>> 
>>>> 
>>>> Only because UTM1 isn't actually a UTM, but a LIE since it only does a 
>>>> partial simulation, not a complete as REQURIED by the definition of a 
>>>> UTM.
>>>> 
>>> 
>>> _DDD()
>>> [00002172] 55         push ebp      ; housekeeping
>>> [00002173] 8bec       mov  ebp,esp  ; housekeeping
>>> [00002175] 6872210000 push 00002172 ; push DDD
>>> [0000217a] e853f4ffff call 000015d2 ; call HHH(DDD)
>>> [0000217f] 83c404     add  esp,+04
>>> [00002182] 5d         pop  ebp
>>> [00002183] c3         ret
>>> Size in bytes:(0018) [00002183]
>>> 
>>> DDD EMULATED BY HHH DOES SPECIFY THAT IT
>>> CANNOT POSSIBLY REACH ITS OWN FINAL HALT STATE.
>> 
>> No, it does not. HHH misintepretes, contrary to the semantics of x86,
>> the specification to mean that.
> 
> It is a truism that a correct x86 emulator
> would emulate itself emulating DDD whenever
> DDD calls this emulator with itself.

Irrelevant. You didn't say anything about a correct emulator or emulation.

-- 
Mikko