Day 9 of Advent of Compiler Optimisations!
Loop with `i * i` inside? Surely the compiler replaces that expensive multiply with clever addition tricks — like manually tracking an accumulator. But no! The compiler keeps the multiply because it enables something more valuable. Why is "more expensive per iteration" sometimes faster overall? The answer lies in how modern CPUs actually execute code.
Read more: https://xania.org/202512/09-induction-variables
Watch: https://youtu.be/vZk7Br6Vh1U
Spent a couple hours reading up on Emacs helm mode. TL;DR: came away slightly impressed but not overwhelmed.
It seems to be a heavyweight replacement for features that are already built in to Emacs, such as selecting multiple completions and acting on them (e.g., buffer lists and file lists in dired). helm-M-x is useful, and two plugins will come in handy: helm-w32-launcher and helm-wikipedia-suggest. My plan is to use it for those 3 for a little while and see if I get sucked in deeper.
matt godbolt