Prototype a fully functional `unsigned int128` type as a Valhalla value class. --------- - [x] I confirm that I make this contribution in accordance with the [OpenJDK Interim AI Policy](https://openjdk.org/legal/ai).
------------- Commit messages: - Merge branch 'lworld' into 8383809 - 8383809: Prototype UInt128 Changes: https://git.openjdk.org/valhalla/pull/2384/files Webrev: https://webrevs.openjdk.org/?repo=valhalla&pr=2384&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8383809 Stats: 2006 lines in 5 files changed: 2005 ins; 0 del; 1 mod Patch: https://git.openjdk.org/valhalla/pull/2384.diff Fetch: git fetch https://git.openjdk.org/valhalla.git pull/2384/head:pull/2384 PR: https://git.openjdk.org/valhalla/pull/2384
