> On Fri, May 6, 2011 at 10:24 PM, Jan Hubicka <hubi...@ucw.cz> wrote: > > Hi, > > while looking at type merging code I noticed that type pairs can be managed > > to be ordered by their UIDs. This save some of hashing overhead in one of > > most intensively querried hashes. > > > > Also gimple_lookup_type_leader is hot function that is better to be inlined. > > > > I also wonder, why unionfind algorithm is not used here to maintain the > > positive answers? > > Can you elaborate?
Well, just use unionfind to record the equivalences found and then prior checking the hashtable ask it for equivalence class representative. Either you will already find that the pairs are equivalent (in faster way than by querying the hash) or you at least save the memory by caching the negative andwers only across the equivalence classes. I hacked quick unionfind two days ago, but the stopper is that the cache is temporarily caching equilvaences in SCC regions. You mentioned it is no longer neccesary, so perhaps if you send me patch to remove this, I can give a try to this idea. Honza
