I was about to say. I bailed out of the industry just as the Xbox One/Ps4 was coming in. Even with the 360/Ps3, it was considered wise to try and steer clear of that kind of low level stuff just for ones sanity. When the X1/Ps4 came in, it was completely abandoned, turns out x86 compilers combined with OoO execution just made that kind of tinkering not only nearly pointless but sometime actually hurt performance.

Nowadays,I suspect it is almost entirely in the hands of the compilers, the API's and the base OS to figure out the gritty details.