faster splitter

[Chris via Digitalmars-d]

On Monday, 30 May 2016 at 18:57:15 UTC, Chris wrote:
> On Monday, 30 May 2016 at 18:20:39 UTC, Andrei Alexandrescu 
> wrote:
>>
>> Please throw this hat into the ring as well: it should improve 
>> average search on large vocabulary dramatically.
>>
>> https://dpaste.dzfl.pl/dc8dc6e1eb53
>>
>> It uses a BM-inspired trick - once the last characters 
>> matched, if the match subsequently fails it needn't start from 
>> the next character in the haystack. The "skip" is computed 
>> lazily and in a separate function so as to keep the loop 
>> tight. All in all a routine worth a look. I wanted to write 
>> this for a long time. -- Andrei
>
> Cool. So far, my experience with separate functions has been 
> that they slow down the loop. But this might do the trick.

Congratulations!

DMD:

./benchmark.dmd
        std: 178 ±31    +36 (4475)  -29 (5344)
     manual: 167 ±46    +82 (2883)  -32 (7054)
       qznc: 114 ±7     +18 (1990)   -5 (7288)
      Chris: 228 ±49    +82 (3050)  -35 (6780)
     Andrei: 103 ±5     +47 ( 658)   -2 (9295)
(avg slowdown vs fastest; absolute deviation)
CPU ID: GenuineIntel Intel(R) Core(TM) i5-4200U CPU @ 1.60GHz

LDC:

        std: 184 ±19    +28 (3420)  -14 (6523)
     manual: 205 ±59   +120 (2463)  -39 (7443)
       qznc: 151 ±25    +44 (2983)  -17 (6911)
      Chris: 194 ±57    +78 (3702)  -46 (6251)
     Andrei: 101 ±2     +42 ( 435)   -1 (9542)
  (avg slowdown vs fastest; absolute deviation)
CPU ID: GenuineIntel Intel(R) Core(TM) i5-4200U CPU @ 1.60GHz