how to benchmark pure functions?

[Siarhei Siamashka]

On Friday, 28 October 2022 at 09:48:14 UTC, ab wrote:
> Thanks to H.S. Teoh and Dennis for the suggestions, they both 
> work. I like the empty asm block a bit more because it is less 
> invasive, but it only works with ldc.

I used the volatileLoad/volatileStore functions to ensure that 
the compiler doesn't find a way to optimize out the code (for 
example, move repetitive calculations out of the loop or even do 
them at compile time) and the RDTSC/RDTSCP instruction via inline 
assembly for measurements: 
https://gist.github.com/ssvb/5c926ed9bc755900fdaac3b71a0f7cfd

The goal was to have a very fast way to check (with no measurable 
overhead) whether reasonable optimization options had been 
supplied to the compiler.