RFR (XS) 8046516: Segmentation fault in JVM (easily reproducible)

[Vladimir Kozlov]

http://cr.openjdk.java.net/~kvn/8046516/webrev/
https://bugs.openjdk.java.net/browse/JDK-8046516

Loop optimization reorg_offsets moves loop invariant arithmetic nodes 
which calculate following loop's limit (which should be invariant) 
inside that loop. As result it cloned by clone_loop and cause the problem.

Place new nodes on the previous loop exit.

Added regression test.

Tested hotspot regression tests.

Thanks,
Vladimir