DSFMT needs a 64-bit interface

[ViralBShah]

DSFMT needs a 64-bit interface. Currently, it seems to use int for array sizes.

[StefanKarpinski]

If we do add this, we should contribute the additions upstream if it's reasonable to do so.

[StefanKarpinski]

Arguably one could also just use the 32-bit interface in a loop for 64-bit values that are large. That would be a Julia-only solution.

[ViralBShah]

I will at least try patch DSFMT to use long instead of int. I think it should be reasonably simple to pull off, and we already patch DSFMT.

[ViralBShah]

As of commit c78b184

julia> @time rand(2^33)
elapsed time: 53.37400007247925 seconds
8589934592-element Float64 Array:
 0.277725 
 0.717841 
 0.508466 
 0.781537 
 0.651427 
 0.471652 
 0.919684 
 0.918566 
 0.87167  
 0.995398 
 0.0112912
 0.856975 
 0.085894 
 0.773804 
 0.799451 
 ⋮        
 0.191464 
 0.504622 
 0.537639 
 0.672729 
 0.828075 
 0.263593 
 0.562722 
 0.423488 
 0.636193 
 0.459945 
 0.956286 
 0.757436 
 0.681872 
 0.83292  
 0.818928 

julia> a = ans;

julia> a[end]
0.8189275296311884

julia> a[end-1000]
0.1262249932227848

[StefanKarpinski]

I have to say, I rather like the vertical ellipsis :-)

I guess this works, but I still don't get why we're not just calling the 32-bit interface in a loop. Is there some reason not to do that instead?

[ViralBShah]

This was just quicker to do, rather than changing a whole bunch of dsfmt wrappers!