Request for reviews (S): 7199742: A lot of C2 OSR compilations of the same method's bci

[Vladimir Kozlov]

http://cr.openjdk.java.net/~kvn/7199742/webrev

CI type flow analysis clone the head of OSR loop and as result the type of 
locals is incorrect in osr_start block in ciTypeFlow info. C2 generates runtime 
checks for locals and uncommon_trap to verify that OSR information is correct 
during execution. The code hit the uncommon trap, method is deoptimized, C2 does 
the same osr compilation again. And this repeats until 
PerMethodRecompilationCutoff/2 (200) is reached.

Don't clone the head of OSR loop.

Thanks,
Vladimir