Request for Reviews (S): JDK-8003585 strength reduce or eliminate range checks for power-of-two sized arrays

Roland Westrelin roland.westrelin at
Wed Sep 30 08:34:18 UTC 2015

I’m picking that one up. Here is a new webrev:

The only change to c2 compared to the previous webrev is that ((x & m) u< m+1) is optimized the same way ((x & m) u<= m) is. Actually, I don’t think that C2 currently produces the ((x & m) u<= m) shape. The IfNode::fold_compares() logic produces the ((x & m) u< m+1) variant. I also added a test case to check the validity of the transformations and ran usual testing on the change.


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