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

[Simon Clubley]

On 2018-07-31, 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:
>>>
>>> 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.
>

I would be interested in an answer to this question as well.

>> 
>>>
>>>
>>> High level languages were a _lot_ simpler back in those days. :-)
>> 
>> Maybe, but the point was there was no other choice of implementation
>> language in those days. And 50+ years later  we're still using those
>> languages (except for IBM FORTRAN, which is sadly lost in time at F77+)
>> now. Which is why the compilers are still mostly assembler. Except maybe for
>> C/C++ which may be heading towards self-hosting.
>
> Okay, I haven't paid a lot of attention to this thread, but what you seem
> to be asserting here is that compilers are still (as now, 2018) written in
> assembler.  If that is the case, I think you really need to reconsider
> your statement.
>

I can believe it for a compiler written decades ago that is still in
active use - look at the amount of Macro-32 code in VMS for example.

However, I find it hard to believe for any newly created compilers.

Simon.

-- 
Simon Clubley, clubley at remove_me.eisner.decus.org-Earth.UFP
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