RFR: 8298824: C2 crash: assert(is_Bool()) failed: invalid node class: ConI

[Christian Hagedorn]

[JDK-8292889](https://bugs.openjdk.org/browse/JDK-8292289) added the following optimization to `BoolNode::Ideal()` for patterns that include `CMoveI` nodes:

https://github.com/openjdk/jdk/blob/fa322e40b68abf0a253040d14414d41f4e01e028/src/hotspot/share/opto/subnode.cpp#L1465-L1472

However, we could have a `CMoveI` during IGVN that will later be folded because the `Bool` condition node was replaced by a constant but IGVN has not processed this node, yet:

 
![Screenshot from 2022-12-16 09-40-28](https://user-images.githubusercontent.com/17833009/208068197-4819b322-604c-412e-8898-3d3546a8a663.png)

We fail when trying to call `as_Bool()` on `28 ConI`. The fix is straight forward to additionally check if we actually have a `BoolNode`.

Thanks,
Christian

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Commit messages:
 - 8298824: C2 crash: assert(is_Bool()) failed: invalid node class: ConI

Changes: https://git.openjdk.org/jdk/pull/11705/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=11705&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8298824
  Stats: 53 lines in 2 files changed: 52 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/11705.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/11705/head:pull/11705

PR: https://git.openjdk.org/jdk/pull/11705