+1

> On Jan 17, 2018, at 11:36 AM, Hannes Wallnöfer <hannes.wallnoe...@oracle.com> 
> wrote:
> 
> Please review: 
> 
> Bug: https://bugs.openjdk.java.net/browse/JDK-8195123
> Webrev: http://cr.openjdk.java.net/~hannesw/8195123/webrev.00/
> 
> This undoes the recent fix for JDK-8193567 (Attila, in case you’re reading, I 
> should have taken your doubts more serously) and replaces it with a different 
> fix.
> 
> Instead of disabling optimistic types within comparison nodes, the new fix  
> avoids the shortcuts for null and undefined comparison if the compared 
> expression contains an optimistic expression. Previously we only checked 
> whether the expression itself was optimistic or contained the expression that 
> triggered the current rest-of compilation. It’s easy to see why we must avoid 
> it also for nested optimistic expressions, as they can trigger deoptimization 
> as well. 
> 
> In my testing, this fixes the performance regression.
> 
> Hannes

Reply via email to