More efficient ranges for Word32

[idontgetoutmuch]

This can now be merged (subject to review of course). I don't think a drop in coverage of 0.1% is serious. Of course we should write more tests but in separate PRs.

[idontgetoutmuch]

@lehins @curiousleo are you happy for me to merge this?

Here are the results for ranges using just bitmask

  Next timing range-restricted System.Random.randomR:
        811,624 randoms generated [System.Random Ints]        ~ 3,312 cycles/int
     10,959,894 randoms generated [System.Random Word16s]     ~ 245 cycles/int
     26,684,542 randoms generated [System.Random Floats]      ~ 101 cycles/int
     28,584,570 randoms generated [System.Random CFloats]     ~ 94.05 cycles/int
     28,721,171 randoms generated [System.Random Doubles]     ~ 93.61 cycles/int
     24,878,218 randoms generated [System.Random CDoubles]    ~ 108 cycles/int
      1,168,144 randoms generated [System.Random Integers]    ~ 2,302 cycles/int
        441,528 randoms generated [System.Random Bools]       ~ 6,089 cycles/int
        380,428 randoms generated [System.Random Chars]       ~ 7,067 cycles/int
         11,658 randoms generated [System.Random BIG Integers] ~ 230,614 cycles/int

and here are the results when using integer multiply for Word32

 Next timing range-restricted System.Random.randomR:
        865,075 randoms generated [System.Random Ints]        ~ 3,087 cycles/int
     16,030,334 randoms generated [System.Random Word16s]     ~ 167 cycles/int
     38,619,176 randoms generated [System.Random Floats]      ~ 69.15 cycles/int
     34,920,119 randoms generated [System.Random CFloats]     ~ 76.47 cycles/int
     37,484,083 randoms generated [System.Random Doubles]     ~ 71.24 cycles/int
     37,316,003 randoms generated [System.Random CDoubles]    ~ 71.56 cycles/int
      1,388,163 randoms generated [System.Random Integers]    ~ 1,924 cycles/int
        761,498 randoms generated [System.Random Bools]       ~ 3,507 cycles/int
        787,128 randoms generated [System.Random Chars]       ~ 3,393 cycles/int
         12,093 randoms generated [System.Random BIG Integers] ~ 220,823 cycles/int

I’d say it was definitely worth merging

[lehins]

Overall looks good to me. Performance boost is always nice ;)

[curiousleo]

🎉