Can you shrink it further?

[Stefan Koch via Digitalmars-d]

On Wednesday, 12 October 2016 at 10:15:17 UTC, Matthias Bentrup 
wrote:
> On Wednesday, 12 October 2016 at 09:23:53 UTC, Stefan Koch 
> wrote:
>> On Wednesday, 12 October 2016 at 08:56:59 UTC, Matthias 
>> Bentrup wrote:
>>> [...]
>>
>> All three are slower than baseline, for my test-case.
>> What did you test it against.
>
> The blns.txt file mentioned upthread.

And what were your timings ?

BTW. the code you posted would not be a proper replacement for 
utf8 popFront since our UTF8-popFront does handle depreacted 
sequences correctly.

making it equivalent to this code :
void pfnew(ref char[] s) @trusted pure nothrow
{
     immutable c = s[0];
     uint char_length = 1;
     if (c < 192)
     {
Lend :
         s = s.ptr[char_length .. s.length];
     } else {
         if (c < 192+32)
         {
             char_length = 2;
         }
         else if (c < 192+32+16)
         {
             char_length = 3;
         }
         else if (c < 192+32+16+8)
         {
             char_length = 4;
         }
         else if (c < 192+32+16+8+4)
         {
             char_length = 5;
         }
         else if (c < 192+32+16+8+4+2)
         {
             char_length = 6;
         }

         char_length = char_length > s.length ? s.length : 
char_length;
         goto Lend;
     }
}