[Lazarus] UTF8LengthFast returning incorrect results on AARCH64 (MacOS)

Marco van de Voort fpc at pascalprogramming.org
Tue Dec 28 15:39:34 CET 2021

Op 12/28/2021 om 3:01 PM schreef Bart via lazarus:
>   -Cpcoreavx  for core 3000 series and higher
> Thanks for that.
> Up to PENTIUMM: PopCnt slower
> COREI : approximately equally fast
> COREAVX PopCnt slightly faster
> COREAVX2 PopCnt slightly faster

On what machine did you test? The settings if for the generated code, 
but the actual processor determines the effective speed.

> Most likely not worth bothering.
> In code can we check (at compile time) for which instructionset the
> code was compiled?
Not that I know. Moreover with AMD etc there would be no simple "x or 
greater"  kind of criterium other than having popcnt

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