Perlin noise benchmark speed

[dennis luehring via Digitalmars-d]

Am 20.06.2014 22:44, schrieb bearophile:
> dennis luehring:
>
>> it does not makes sense to "optmized" this example more and
>> more - it should be fast with the original version
>
> But the original code is not fast. So someone has to find what's
> broken. I have shown part of the broken parts to fix (floor on
> ldc2).
>
> Also, the original code is not written in a fully idiomatic way,
> also because unfortunately today the "lazy" way to write D code
> is not always the best/right way (example: you have to add ton of
> immutable/const, and annotations, because immutability is not the
> default), so a code fix is good.
>
> Bye,
> bearophile
>

as long as you find out its a library thing

the c version is without any annotations and immutable/const the fastest 
- so whats the problem with D here, it can't(shouln't) be that one needs 
to work/change that much on such simple code to reach c speed