On Aug 6, 2013, at 2:43 PM, Remi Forax <fo...@univ-mlv.fr> wrote: > On 08/06/2013 11:11 PM, Dan Smith wrote: >> Please review this warnings cleanup. >> >> Bug: http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=8022442 (not yet >> visible) >> Webrev: http://cr.openjdk.java.net/~dlsmith/8022442/webrev.00/ >> >> —Dan > > Hi Dan, > I've seen that you have introduce a common super interface for entry and tree > node, > I suppose that you check that there is no performance regression. > I wonder if an abstract class is not better than an interface because as far > as I know > CHA implemented in hotspot doesn't work on interface > (but I may be wrong, there is perhaps a special optimization for arrays).
To make sure I understand: your concern is that an aastore will be more expensive when assigning to a KeyValueData[] than to an Object[] (or even to SomeOtherClass[])? For what it's worth, all assignments to table[i] are statically known to be safe. E.g.: Entry<K,V> next = (Entry<K,V>) e.next; ... table[i] = next; So surely a smart VM only does the check once? Here are some other things that might be concerns, but don't apply here: - interface method invocations: there are no methods in the interface to invoke - checkcast to an interface: all the casts are to concrete classes (Entry, TreeBin, TreeNode) (There are some unchecked casts from KeyValueData to KeyValueData with different type parameters, but I assume these don't cause any checkcasts.) —Dan
