https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68654
--- Comment #20 from rguenther at suse dot de <rguenther at suse dot de> --- On Tue, 26 Jan 2016, law at redhat dot com wrote: > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68654 > > --- Comment #19 from Jeffrey A. Law <law at redhat dot com> --- > What's initially more important than a particular improvement or degradation > of > performance is bringing more stability to the coalescing results -- so that we > can focus on issues with coalescing rather than getting distracted by the > semi-random performance improvements/drops that we have now. Well, you can simply insert a pass_release_ssa_names before pass_expand then which will compact SSA names for you. It keeps SSA name ordering the same though so it probably doesn't gain anything. Well, and then make the coalesce list stable by preserving the coalesce candidate creation ordering (which works by walking BBs and thus should be more stable in some sense)
