Re: GCC

[Martin <mjb at cs dot bath dot ac dot uk>]

> > It strikes me this is part of a larger problem.  It seems there is (in
> > many companies / institutions there is a large divide between the people
> > who design processors and the people who write compilers.
> Well it's going a little off-topic,
[apologies to list (admins) if this thread is considered OT]

> but this doesn't always happen.
Oh no.  I was just saying that it seems to me that it happens too often
- there are many noteable examples where it hasn't and they've all been
technically very strong architectures (and easy ones to write compilers
for).  It seems there is a real advantage to doing things like this - I
was just pondering why it doesn't happen more often.

> There will always be situations where for very good reasons specific 
> instructions will be added to an ISA but that may be hard to utilize 
> well within gcc.  There may well be very good reasons why these 
> instructions make sense though and arguing that a more pure-RISC 
> strategy (one that makes it easy to target with compilers) will solve 
> all of the world's problems isn't the right answer either ;-)
Far from it - I'm not saying that people should only design processors
to make compiling for them as simple as possible.  It just strikes me
that with a little more communication between the developer communities
better results could be achieved.  Just my opinion and perhaps this kind
of thing happens a lot more than I though and I am horribly mistaken,

> FWIW though I'd note that I've generally found that the most bizarre 
> instructions do not originate with the processor designers but from 
> operating system and application developers who demand magic 
> instructions to save cycles in critical places.  These are usually also 
> the same people who complain  when the compiler can't use their magic 
> instructions very well :-)
:-D  I can't say I'm surprised by this - another developer community who
should probabily work more with compiler and processor design teams.

Cheers,
 - Martin