On Sat, 2014-12-06 at 19:21 +0000, Sebastian Pop wrote: > > I think it does not make sense to duplicate paths at -Os: I disabled the FSM > > jump-threading when optimizing for size like this. > > > > diff --git a/gcc/tree-ssa-threadedge.c b/gcc/tree-ssa-threadedge.c > > index 29b20c8..ce70311 100644 > > --- a/gcc/tree-ssa-threadedge.c > > +++ b/gcc/tree-ssa-threadedge.c > > @@ -1335,8 +1335,9 @@ thread_through_normal_block (edge e, > > return 1; > > } > > > > if (!flag_expensive_optimizations > > + || optimize_function_for_size_p (cfun) > > || TREE_CODE (cond) != SSA_NAME > > || e->dest->loop_father != e->src->loop_father > > || loop_depth (e->dest->loop_father) == 0) > > return 0; > > > > I will regstrap and commit the attached patch. > > Bootstrapped and regression tested on x86_64-linux. > Committed r218451. > > Sebastian
Thanks for getting all this checked in Sebastian, I have tested it on coremark and I am getting the speed up that I expect. But I am a little confused about turning off jump threading. I am getting the optimization on coremark with -O3 and that is great and if I use '-O3 -fno-expensive-optimizations' then I don't see this part of the jump threading, also great. But I was surprised that if I just used '-O3 -fno-thread-jumps' then I still see this optimization. Is that expected? Should this test also check flag_thread_jumps? Or should that be getting checked somewhere else? Steve Ellcey
