DeVault: Announcing the Hare programming language
DeVault: Announcing the Hare programming language
Posted May 6, 2022 0:28 UTC (Fri) by khim (subscriber, #9252)In reply to: DeVault: Announcing the Hare programming language by Vipketsh
Parent article: DeVault: Announcing the Hare programming language
> Since everything is about optimising output, again, I would hope that there were at least *some* benchmarks published along with the new optimisation to show that maintaining the optimisation pass for the future is a good idea.
True and you can find such benchmarks in the bugzilla (or github for clang). But nobody bothers to measure impact of optimizations based on different UBs. Because the assumption is that code doesn't have any.
In the end you have hundreds of passes and absolutely zero knowledge about which of them are applicable in which cases (except for a few, niche, UBs which are simple enough to deserve a dedicated flag).
> On the flip side optimisation passes can turn out to be meaningless because some other new passes don't create the sequences any more for it to be meaningful.Sure. Compiler writers keep track of these things. What they don't keep is mapping between UBs and optimizations (again: with exception of explicitly created flags like -fstrong-aliasing or -fwrapv).
You can measure effect of different optimization passes, but you have absolutely no idea which of them are safe or not safe to use when you want to turn some UB into defined behavior.