Originally found here:
http://stackoverflow.com/a/24899011/2613885

The benchmark from http://cr.openjdk.java.net/~shade/8051725/ yields:

o.o.IfSetneBench.test0 2.286 0.011 ns/op
o.o.IfSetneBench.test1 1.010 0.003 ns/op
o.o.IfSetneBench.test1neg 1.010 0.003 ns/op
o.o.IfSetneBench.test42 1.011 0.005 ns/op
o.o.IfSetneBench.test42neg 1.008 0.002 ns/op

Notice test0 is slower than any other variant. This is because it indeed uses the weird SETNE optimization:
 http://cr.openjdk.java.net/~shade/8051725/test0.perfasm

...while other tests are doing the plain cmp:
 http://cr.openjdk.java.net/~shade/8051725/test1.perfasm