https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111828
--- Comment #6 from Peter Bergner <bergner at gcc dot gnu.org> --- (In reply to Kewen Lin from comment #3) > The motivation of this request is to try our best to make power10 attributed > code inline more power8/power9 attribute code which likely includes some > inline asm but not HTM related as the quoted OSS shows. For now, for one > function which has any non-empty inline asm string, we would consider it's > possible to have HTM code so it's unsafe to inline it. We've hit this issue (attempting to inline some Power8/9 function into a Power10 caller) before with another project (I forget which) and the solution used was to add no-htm to the attribute target options (ie, "cpu=power8,no-htm"). > Users usually think higher cpu attributed code can safely inline lower cpu > attributed code, but it's out of expectation for power10 code inlining > power8/power9 code as we drops HTM from power10. If we can support it > better, users don't need more extra efforts to teach about it. Ideally, we could just go back in time and not enable HTM by default on Power8/9 and force the user to always use -mhtm if they need HTM support. That ship has sailed though. That said, I think nearly all (all?) HTM usage on Power uses our HTM built-in functions. Maybe we could remove OPTION_MASK_HTM from the power8/power9 default flags and only add it back in if we detect the use of an HTM built-in function?
