RFR: [jdk7u] 8028471: PPC64 (part 215): opto: Extend ImplicitNullCheck optimization.

[Lindenmaier, Goetz]

Hi

I would like to downport 8028471 from jdk8 to jdk7.
Major parts of this change came with bulk checkin

"8165807<https://bugs.openjdk.java.net/browse/JDK-8165807>: PPC64: Backport PPC64 port to OpenJDK 7"



This contains some edits we did during review of 8028471 when

we moved the change from aix 7 to main 9 repos. It also contains

the parts missing in os_bsd.hpp.  The edits in lcm should

only affect AIX.

http://cr.openjdk.java.net/~goetz/wr17/8028471-macErr/webrev.01/

Florian, could you please verify this on bsd?

Best regards,
  Goetz.