> On 16 Jan 2026, at 5:56 PM, Jan Hubicka <[email protected]> wrote: > > External email: Use caution opening links or attachments > > >> Thank you Honza for the review >> >> >> The default value was tuned according to the target applications - large >> applications that benefit from the higher size. This results in majority of >> the target applications not needing param adjustment. I see ~5-10% >> improvement for the current default over a lower value. >> >> The adjustment I made here was for additional build time improvement >> specifically for GCC bootstrap with the intention that the target >> applications can use the pass without needing it. > > I see that 5-10% improvement is quite important for the specific > use-case. It is kind of unfortunate that we need to tune the parameter > so high. Is it something that can be fixed by better code placement > across adjacent partitions (which can be acomplished by tp_first_run > machinery and also your new numbered textsubsections) or is it really > about late IPA optimizations (such as register alloation) being important > and ltrans partition being in a way? > > I think we should go with reasonable defaults (which does not bow up > build times) in GCC, so perhaps param should be lowered by default to > what we need for bootstrap and have the target app to bump it up in its > config. > > Hozna
Unfortunately, it’s about IPA optimizations and specifically how many clones are created - having too low a default will blow up the code size. Following your suggestion, I’ll try with a lowered default - meeting halfway between current default and the param here so that we don’t blow up build time and also the apps don’t require too much adjustment. I’ll be back with that patch Thanks, Prachi
