Thank you Honza for the review > On 15 Jan 2026, at 7:57 AM, Jan Hubicka <[email protected]> wrote: > > External email: Use caution opening links or attachments > > >> Hi, >> >> As discussed at Cauldron, I’m sending a 3 patch series that addresses the >> review comments about the compile-time improvement and introduces C++ >> template heuristics which requires the data structure support added in the >> compile-time patch [2/3]. >> >> [Patch 1/3] >> This patch turns off -fipa-reorder-for-locality for -fprofile-generate >> because >> it's not required and contributes to the bloated time taken by bootstrap. It >> also reduces the partition size by half; the increased number of partitions >> speeds up LTRANS phase. >> >> Bootstrapped and tested on aarch64-none-linux-gnu. OK for mainline? > This really feels like a workaround especially with the --param value. > Can't we just adjust the default to get reasonable build times? How much > difference you see with the value change in benchmarks?
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. > > Honza >> >> Signed-off-by: Prachi Godbole <[email protected]> >> >> config/ChangeLog: >> >> * bootstrap-lto-locality.mk (STAGE2_CFLAGS): Add param >> lto-max-locality-partition. >> (STAGE3_CFLAGS): Ditto. >> (STAGEprofile_CFLAGS): Remove -fipa-reorder-for-locality. >> (STAGEtrain_CFLAGS): Ditto.
