RFR: 8240363: Refactor Compile::Output() to its own Phase

[Vladimir Ivanov]

> http://cr.openjdk.java.net/~eosterlund/8240363/webrev.00/

Nice refactoring, Erik!

src/hotspot/share/opto/output.hpp:

+ class PhaseOutput : public Phase {
...
+   Compile*               _compile;

Every Phase already has a cached Compile* instance (named as C) [1].

Right now, you have a mix of _compile, C, and Compile::current() used in 
the code. Please, use C instead.

Otherwise, looks good.

Best regards,
Vladimir Ivanov

[1] 
http://hg.openjdk.java.net/jdk/jdk/file/tip/src/hotspot/share/opto/phase.hpp#l138