Array bound checks removal increasing importance

["Nordlöw" via Digitalmars-d]

> bound tests. This means that optimizing away bound checks is 
> becoming more and more important in D. And D can't ignore this

Expressions like

x[0 .. $/n]

and

x[$/n .. $]

are important in many divide and conquer (recursive) algorithms 
such as quick-sort and shall not need bounds check simply because

0 <= $/n <= $, when n >=1

I've looked around in DMD for a suitable place to add checks for 
this but haven't found the spot where range-check is injected. 
Help anyone?