the patch has been committed today as: https://gcc.gnu.org/viewcvs/gcc?view=revision&revision=266627 <https://gcc.gnu.org/viewcvs/gcc?view=revision&revision=266627>
I will try to update the gcc9 change page soon. thanks. Qing > On Nov 28, 2018, at 2:24 PM, Qing Zhao <qing.z...@oracle.com> wrote: > >> >> On Nov 28, 2018, at 9:52 AM, Jan Hubicka <hubi...@ucw.cz> wrote: >> >>> >>> 2018-11-20 qing zhao <qing.z...@oracle.com> >>> >>> * cif-code.def (EXTERN_LIVE_ONLY_STATIC): New CIF code. >>> * common.opt: Add -flive-patching flag. >>> * doc/invoke.texi: Document -flive-patching. >>> * flag-types.h (enum live_patching_level): New enum. >>> * ipa-inline.c (can_inline_edge_p): Disable external functions from >>> inlining when flag_live_patching is LIVE_PATCHING_INLINE_ONLY_STATIC. >>> * opts.c (control_options_for_live_patching): New function. >>> (finish_options): Make flag_live_patching incompatible with flag_lto. >>> Control IPA optimizations based on different levels of >>> flag_live_patching. >>> >>> gcc/testsuite/ChangeLog: >>> >>> 2018-11-20 qing zhao <qing.z...@oracle.com> >>> >>> * gcc.dg/live-patching-1.c: New test. >>> * gcc.dg/live-patching-2.c: New test. >>> * gcc.dg/live-patching-3.c: New test. >>> * gcc.dg/tree-ssa/writeonly-3.c: New test. >>> * gcc.target/i386/ipa-stack-alignment-2.c: New test. >>> >> >> I am still somewhat worried about possible use with C++ programs where >> we will kill all inlining of comdats, but I guess we could discuss that >> when it becomes an issue. > > Okay. If this will be a problem later when we use live-patching in more C++ > applications, let’s > revisit it at that time. > >> + >> + /* FIXME: disable unreachable code removal. */ >> >> Disabling unreachable code removal will really introduce a lot of extra >> dead code, can't live patches just provide what they need if the code >> was earlier removed. >> + >> + /* discovery of functions/variables with no address taken. */ >> + if (opts_set->x_flag_ipa_reference_addressable >> + && opts->x_flag_ipa_reference_addressable) >> + error_at (loc, >> + "%<-fipa-reference-addressable%> is incompatible with " >> + "%<-flive-patching=inline-only-static|inline-clone%>"); >> + else >> + opts->x_flag_ipa_reference_addressable = 0; >> + >> + /* ipa stack alignment propagation. */ >> + if (opts_set->x_flag_ipa_stack_alignment >> + && opts->x_flag_ipa_stack_alignment) >> + error_at (loc, >> + "%<-fipa-stack-alignment%> is incompatible with " >> + "%<-flive-patching=inline-only-static|inline-clone%>"); >> + else >> + opts->x_flag_ipa_stack_alignment = 0; >> >> Shall we also disable nothrow or we will worry about C++ only ter? > > This is also mainly for C++ applications, so currently should not be a > problem. > But I can add a separate simple patch to add another flag to control nothrow > propagation and disable it when -flive-patching is ON. > >> >> Patch is OK, > > thanks for the review. > > I will commit the patch very soon. > > Qing >> thanks! >> Honza
