RFR: 8359678: C2: assert(static_cast<T1>(result) == thing) caused by ReverseBytesNode::Value()

[Hannes Greule]

Fixes an assertion when passing an int larger than short/char to the corresponding reverseBytes method in a constant-folding scenario. By just using static_cast, we can ignore the upper bytes and just swap the lower bytes.

Using jasm, I added a test case that covers such inputs. It felt easier to test this way than the other scenarios mentioned in the bug report.

I also removed the redundant checked_cast calls from the int/long case; we already have the correct type there.

Please review. Thanks.

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Commit messages:
 - fix
 - test

Changes: https://git.openjdk.org/jdk/pull/25988/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=25988&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8359678
  Stats: 83 lines in 3 files changed: 74 ins; 2 del; 7 mod
  Patch: https://git.openjdk.org/jdk/pull/25988.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/25988/head:pull/25988

PR: https://git.openjdk.org/jdk/pull/25988