I don’t think any of these optimizations require more modern hardware?
themoken@startrek.website
on 31 Oct 00:44
nextcollapse
Right. GCC -f optimizations are basically like “how hard are we going to try to be clever” and are, I believe, orthogonal to the actual instructions used. Machine dependent args start with -m, like -march or -mavx etc.
ozymandias117@lemmy.world
on 31 Oct 00:47
collapse
I was reasonably certain, but left it open in case OP knew of some edge case where flags that are intended to be machine independent caused bugs on different architectures
Yeah, adding a separate microarchitecture like amd64v3 would be a separate item. They might be able to do that with amd64v3 overlay repos that only contain packages that most benefit from the newer microarchitecture.
ryannathans@aussie.zone
on 30 Oct 21:37
nextcollapse
How do they avoid the subsequent bugs O3 tends to produce?
communist@lemmy.frozeninferno.xyz
on 30 Oct 22:30
nextcollapse
threaded - newest
Not like Ubuntu works very well on old hardware but hopefully O2 support will still be there. Many people need it.
-O2 vs -O3 adds
-fgcse-after-reload -fipa-cp-clone -floop-interchange -floop-unroll-and-jam -fpeel-loops -fpredictive-commoning -fsplit-loops -fsplit-paths -ftree-loop-distribution -ftree-partial-pre -funswitch-loops -fvect-cost-model=dynamic -fversion-loops-for-stridesI don’t think any of these optimizations require more modern hardware?
Right. GCC -f optimizations are basically like “how hard are we going to try to be clever” and are, I believe, orthogonal to the actual instructions used. Machine dependent args start with -m, like -march or -mavx etc.
I was reasonably certain, but left it open in case OP knew of some edge case where flags that are intended to be machine independent caused bugs on different architectures
Yeah, adding a separate microarchitecture like amd64v3 would be a separate item. They might be able to do that with amd64v3 overlay repos that only contain packages that most benefit from the newer microarchitecture.
How do they avoid the subsequent bugs O3 tends to produce?
They don’t.
First time I’m hearing of this. Do you have some more details?
It’s complicated.
Gentoo users in shambles
Bah, they’ll never have my precious
-march=native!I doubt they want my fun and safe math optimizations either tbh
Jokes on you, my system is (mostly) -O3
too fancy for -O2? lol
Yes
op-ti-mize [verb (trans.)]* … (gcc) to modify executable code so that it fails more quickly.