RFR: 8317723: C2: CountedLoopEndNodes and Zero Trip Guards are wrongly treated as Runtime Predicate

[Christian Hagedorn]

In `testCountedLoopEndAsRuntimePredicate()`, a `CountedLoopEndNode` is wrongly treated as Runtime Predicate and added to a Predicate Block. This happens because a predicate trap ends up at one of the projections of the `CountedLoopEndNode` due to folding some other nodes:

![image](https://github.com/openjdk/jdk/assets/17833009/d00af4aa-e962-454f-b7cd-5984dfda293f)

The verification code then reports this failure when trying to find all predicates above `530 CountedLoop`. I've fixed `RuntimePredicate::is_success_proj()` to only treat an `IfNode` or a `RangeCheckNode` as Runtime Predicate.

We could also end up treating a zero trip guard If node with an `OpaqueZeroTripGuardNode` as Runtime Predicate (see `testZeroTripGuardAsRuntimePredicate()`):

![image](https://github.com/openjdk/jdk/assets/17833009/a515bdfb-b599-4a81-902c-e85b980f5899)

This could also potentially lead to problems. I've improved `RuntimePredicate::is_success_proj()` to additionally exclude zero trip guard checks. I've strengthened the verification code accordingly such that it would have failed with  `testZeroTripGuardAsRuntimePredicate()`.

Thanks,
Christian

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Commit messages:
 - 8317723: C2: CountedLoopEndNodes are wrongly treated as Runtime Predicate

Changes: https://git.openjdk.org/jdk/pull/16596/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=16596&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8317723
  Stats: 132 lines in 5 files changed: 131 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/16596.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/16596/head:pull/16596

PR: https://git.openjdk.org/jdk/pull/16596