[Info-vax] The (now lost) future of Alpha.

[Bill Gunshannon]

On 08/01/2018 10:37 PM, Tim Sneddon wrote:
> invalid <address at is.invalid> wrote:
>> On 2018-08-01, Tim Sneddon <tsneddon at panix.com> wrote:
>>> invalid <address at is.invalid> wrote:
>>>> On 2018-07-29, Simon Clubley <clubley at remove_me.eisner.decus.org-Earth.UFP> wrote:
>>>>> On 2018-07-29, invalid <address at is.invalid> wrote:
>>>>>> On 2018-07-24, Arne Vajh??j <arne at vajhoej.dk> wrote:
>>>>>>>
>>>>>>> Given that a compiler basically reads a text file and writes a file
>>>>>>> (text if it outputs assembler and binary if it outputs object code),
>>>>>>> then I find it very difficult to see why a compiler would have to be
>>>>>>> written in assembler.
>>>>>>
>>>>>> It was the best language for the job and in a lot of ways still is.
>>>>>>
>>>>>
>>>>> It may just be me, but I don't fancy the idea of writing a LL(1) parser
>>>>> (assuming the language is suitable for LL(1) parsing), an optimiser or
>>>>> a code generator in assembly language. :-)
>>>>
>>>> Once you've done it, you mostly don't have to do it again.
>>>>
>>>> The PL/I compiler had over 200 passes at one time. That's a lot scarier than
>>>> writing any parser in any language ;)
>>>
>>> What? 200 passes? As someone who is likely more knowledgable than most in
>>> this particular arena, just what are you talking about?  Please, site
>>> examples and references, I'm very interested.
>>
>> Look on bitsavers for the MVS manuals, then PLM (Program Logic Manuals) then
>> find PL/I
>>
> 
> Classic!  The anti-vaxxer of the compiler world!
> 
> You: Here, I'm making some wild claim!
> Me: Prove it!
> You: Nah! You do it.
> 
> 200 passes?  This is ridiculous stuff.  Compilers still written in assembler
> 50 years later?  Wow!  I think I'll let you have a great time winding
> everyone else up, I've got real work to do.  Funnily enough, on compilers.
> The oldest probably being around 40-45 years old.  Crazy thing though, not
> written in assembler...anywhere...
> 

I'll second that. I have worked with compilers since the very early
80's on Minis and Micros and have never seen one written in assembler.
I have a number of books on compiler writing and development (surely
everyone here is familiar with The Dragon Book) and not one of them
talks about or provides examples of compilers written in assembler.

bill