Avoiding Slice Checking

[deadalnix via Digitalmars-d]

On Wednesday, 21 January 2015 at 23:50:44 UTC, Nordlöw wrote:
> As a follow up to
>
> https://github.com/D-Programming-Language/dmd/pull/4293
>
> would it be possible to also avoid range-checking in 
> expressions such as
>
>     x[0 .. $/n]
>
> and
>
>     x[$/n .. $]
>
> where n is an integer compile-time constant >= 2.
>
> I'm askingbecause this is a reoccurring pattern in D-style 
> binary divide-and-conquer algorithms and would be a good 
> show-case for D from a performance standpoint.
>
> Is DMD prepared for (easily) adding this to e2ir.c and 
> expression.c?

That is reasonable to expect a compiler to remove such a check 
with optimization enabled already. I'm not sure about DMD, but 
I'd be willing to bet that LDC and GDC already do it.