howto count lines - fast

[Patrick Schluter via Digitalmars-d-learn]

On Thursday, 1 June 2017 at 04:39:17 UTC, Jonathan M Davis wrote:
> On Wednesday, May 31, 2017 16:03:54 H. S. Teoh via 
> Digitalmars-d-learn wrote:
>> [...]
> Digitalmars-d-learn wrote:
>> [...]
>
> If you're really trying to make it fast, there may be something 
> that you can do with SIMD. IIRC, Brian Schott did that with his 
> lexer (or maybe he was just talking about it - I don't remember 
> for sure).
>

See my link above to realdworldtech. Using SIMD can give good 
results in micro-benchmarks but completely screw up performance 
of other things in practice (the alignment requirements are heavy 
and result in code bloat, cache misses, TLB misses, cost of 
context switches, AVX warm up time (Agner Fog observed around 
10000 cycles before AVX switches from 128 bits to 256 bits 
operations), reduced turboing, etc.).