Why duplicating the merger functions in dyn-ipa.c? Should those in libgcov-merge.c be reused?
The refactoring of gcov_exit_write_gcda should probably be done in a separate patch -- preferably submitted to trunk too. David On Mon, May 19, 2014 at 10:08 PM, Teresa Johnson <tejohn...@google.com> wrote: > Ping. > Teresa > > On Wed, May 14, 2014 at 4:39 PM, Teresa Johnson <tejohn...@google.com> wrote: >> This patch applies profile fixups to COMDATs on the dyn ipa callgraph >> at the end of LIPO module grouping (either in the profile gen run or >> in gcov-tool). This is to address issues with missing profiles in the >> out-of-line COMDAT copies not selected by the linker, and indirect >> call profiles that target a module not included in the module group. >> By default, both fixups are enabled, but can be controlled by a >> profile-gen parameter, an environment variable, and a gcov-tool >> option. >> >> The fixups assume that functions with the same lineno and cfg checksum >> are copies of the same COMDAT. This is made more likely by ensuring >> that in LIPO mode we include the full mangled name in the >> lineno_checksum. >> >> For the counter fixup, we merge all non-zero profiles with matching >> checksums and copy the merged profile into copies with all-zero >> profiles. >> >> For the indirect counter fixup, if an indirect call profile target is >> not in the module group, we look for a matching checksum copy in the >> primary module and if exactly one is found we change the target to >> that. >> >> If any fixups are applied, the gcda files are rewritten after module >> grouping. >> >> This also required a couple of other changes to the optimizer. During >> cgraph node resolution, we were arbitrarily selecting a copy that had >> non-zero profiles. Now there are many more to choose from, so we will >> prefer the primary module copy if it is non-zero. Also, during cloning >> for inlining, we only want to update the profile on the callee node if >> we are inlining into the resolved node caller node. We were already >> doing this for AutoFDO, and need to do this here now that many node >> copies have the same profile. >> >> Patch attached. Tested with regression tests and internal benchmarks. >> Ok for google branches? >> >> Thanks, >> Teresa >> >> >> >> -- >> Teresa Johnson | Software Engineer | tejohn...@google.com | 408-460-2413 > > > > -- > Teresa Johnson | Software Engineer | tejohn...@google.com | 408-460-2413
