> Hi, > > On Mon, Aug 31 2020, Feng Xue OS wrote: > > This patch is to fix a bug that cost that is used to evaluate clone > > candidate > > becomes negative due to integer overflow. > > > > Feng > > --- > > 2020-08-31 Feng Xue <f...@os.amperecomputing.com> > > > > gcc/ > > PR tree-optimization/96806 > > the component is "ipa," please change that when you commit the patch. > > > * ipa-cp.c (decide_about_value): Use safe_add to avoid cost addition > > overflow. > > assuming you have bootstrapped and tested it, it is OK for both trunk > and all affected release branches.
I have already added caps on things that come from profile counts so things do not overflow, but I think in longer run we want to simply use sreals here.. > > && !good_cloning_opportunity_p (node, > > - val->local_time_benefit > > - + val->prop_time_benefit, > > + safe_add (val->local_time_benefit, > > + val->prop_time_benefit), > > freq_sum, count_sum, > > - val->local_size_cost > > - + val->prop_size_cost)) > > + safe_add (val->local_size_cost, > > + val->prop_size_cost))) Is it also size cost that may overflow? That seem bit odd ;) Honza > > return false; > > > > if (dump_file) > > [...]
