RFR: 8365570: C2 fails assert(false) failed: Unexpected node in SuperWord truncation: CastII [v2]

[Jasmine Karthikeyan]

> Hi all,
> This is a quick patch for the assert failure in superword truncation with CastII. I've added a check for all constraint cast nodes, and attached a reduced version of the fuzzer test. Thanks!

Jasmine Karthikeyan has updated the pull request incrementally with one additional commit since the last revision:

  Update comment for constraint casts

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/26827/files
  - new: https://git.openjdk.org/jdk/pull/26827/files/d5c4dda2..d6c81a9d

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=26827&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=26827&range=00-01

  Stats: 7 lines in 1 file changed: 5 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/26827.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/26827/head:pull/26827

PR: https://git.openjdk.org/jdk/pull/26827