[11u] RFR: 8257574: C2: "failed: parsing found no loops but there are some" assert failure

[Doerr, Martin]

Hi,

JDK-8257574 is backported to 11.0.12-oracle. I'd like to backport it for parity.
It doesn't apply cleanly because of a naming difference in the code which gets replaced:
The patch wants to remove "is_innermost()", but it's called "is_inner()" in 11u.

Bug:
https://bugs.openjdk.java.net/browse/JDK-8257574

Original change:
https://git.openjdk.java.net/jdk/commit/86b65756

11u backport:
http://cr.openjdk.java.net/~mdoerr/8257574_C2_11u/webrev.00/

Please review.

Best regards,
Martin