Interesting performance results on Crc port from zlib

[James Blachly]

On 1/24/21 10:26 AM, Igor wrote:
> build type   |  zlib  | phobos | zlibdport |
> --------------------------------------------
> dmd debug    |  240ms |  272ms |     211ms |
> dmd release  |  237ms |  279ms |     202ms |
> ldc debug    |  238ms |  136ms |     264ms |
> ldc release  |  238ms |  132ms |     125ms |
> 
> Calling actual zlib is pretty constant, I guess because it uses 
> precompiled static library. What is really surprising is how much faster 
> is the port from original zlib. Anyone has any idea how can that be?
> 

If you did not compile zlib yourself, it is possible that your ported 
version uses advanced native instructions that are far more efficient 
e.g. handling data in parallel, whereas the zlib distributed with your 
operating system may be compiled for least common denominator CPU