Which optimisations are are easier or perhaps only possible in the frontend ?

[Stefan Koch via Digitalmars-d]

On Thursday, 11 December 2014 at 12:20:50 UTC, Manu via 
Digitalmars-d wrote:
> I've often thought one of the biggest wins that would seem to 
> affect
> my code would be comprehensive value range propagation.
> assert's and contracts can give value range information to the
> compiler, also comparison statements, bit masks, casts, etc, can
> truncate the possible value range, which can create many 
> opportunities
> for optimisations. It would also be really nice to eliminate 
> errors
> associated with down-casting.

Great suggestion Manu.
We are on the same page here!
I will see what I can do about data-flow-analysis in the frontend.

This has been requested before. Time to do something about it :)
Just don't expect results too quickly, qcc (and looking for a 
job) takes much of my time.