stride in slices

[Timon Gehr]

On 05.06.2018 18:50, DigitalDesigns wrote:
> With a for loop, it is pretty much a wrapper on internal cpu logic so it 
> will be near as fast as possible.

This is not even close to being true for modern CPUs. There are a lot of 
architectural and micro-architectural details that affect performance 
but are not visible or accessible in your for loop. If you care about 
performance, you will need to test anyway, as even rather sophisticated 
models of CPU performance don't get everything right.

Also, it is often not necessary to be "as fast as possible". It is 
usually more helpful to figure out where the bottleneck is for your code 
and concentrate optimization effort there, which you can do more 
effectively if you can save time and effort for the remaining parts of 
your program by writing simple and obviously correct range-based code, 
which often will be fast as well.