[8u] RFR: 8214862: assert(proj != __null) at compile.cpp:3251

[Roland Westrelin]

With the backport of 8146612 (C2: Precedence edges specification
violated) applied, the 11u change still does not apply cleanly because
11u has an extra method
(PhaseIdealLoop::create_reserve_version_of_loop()) that doesn't exist in
8u. Otherwise, the change applies cleanly.

http://cr.openjdk.java.net/~roland/8214862.8u/webrev.00/

Initial change:
https://bugs.openjdk.java.net/browse/JDK-8214862
https://hg.openjdk.java.net/jdk-updates/jdk11u-dev/rev/fc09935145db

Tested with tier1.

Roland.