RFR (S) 8046275: Fastdebug build failing on jdk9/hs/ control jobs after pulling some hs-comp changes

[Vladimir Kozlov]

http://cr.openjdk.java.net/~kvn/8046275/webrev
https://bugs.openjdk.java.net/browse/JDK-8046275

Loop optimization method clone_loop() collects all outside IF nodes 
which use a Bool node inside a cloned loop and then constructs new Bool 
node of Phi to replace the Phi of cloned Bool nodes after loop body is 
cloned. This code is not triggered because in bug case IF node 
references Bool through Opaque node - it is loop limit check predicate. 
We keep Opaque in loop predicates until the end of loop opts.

Tested with hotspot regression tests, JPRT control build (including 
'deploy').

I was not able to write simple test. The problem is always reproduced 
with control JDK build with 'deploy'.

Thanks,
Vladimir