Re: Threading the compiler

["Daniel Berlin" <dberlin at dberlin dot org>]

On 11/10/06, Mike Stump <mrs@apple.com> wrote:
> On Nov 10, 2006, at 12:46 PM, H. J. Lu wrote:
> > Will use C++ help or hurt compiler parallelism? Does it really matter?
>
> I'm not an expert, but, in the simple world I want, I want it to not
> matter in the least.  For the people writing most code in the
> compiler, I want clear simple rules for them to follow.
>
> For example, google uses mapreduce http://labs.google.com/papers/
> mapreduce.html as a primitive, and there are a few experts that
> manage that code, and everyone else just mindlessly uses it.  The
> rules are explained to them, and they just follow the rules and it
> just works.  No locking, no atomic, no volatile, no cleaver lock free
> code, no algorithmic changes (other than decomposing into isolated
> composable parts) .  I'd like something similar for us.

I think the part that makes me the giggle the most is that we assume
that the actual mapper code is not threadsafe by default, and won't
run multiple threads of the mapper.