[lworld] RFR: 8325660: [lworld] Update C2 to support new value construction scheme from JEP 401

[Tobias Hartmann]

This is a first change to update C2 to support the new value construction scheme from JEP 401. All hotspot/compiler/valhalla tests now pass but there are many known issues and disabled optimizations. Follow-up work will be done with [JDK-8325106](https://bugs.openjdk.org/browse/JDK-8325106) and is marked with `TODO 8325106` in the code.

For runtime and C1 changes, see [JDK-8326595](https://bugs.openjdk.org/browse/JDK-8326595).

Thanks,
Tobias

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Commit messages:
 - Removed Integer usages from some tests
 - Fixed TestArrays.java
 - Even more fixes
 - Missing stopped checks
 - More Todos
 - Another TODO
 - Uncommented debug code
 - Workaround for arraycopy intrinsic
 - Removed some dead code in C1
 - Fix for 8328470 and new test
 - ... and 14 more: https://git.openjdk.org/valhalla/compare/292622d0...ce1b1511

Changes: https://git.openjdk.org/valhalla/pull/1049/files
  Webrev: https://webrevs.openjdk.org/?repo=valhalla&pr=1049&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8325660
  Stats: 2215 lines in 77 files changed: 609 ins; 436 del; 1170 mod
  Patch: https://git.openjdk.org/valhalla/pull/1049.diff
  Fetch: git fetch https://git.openjdk.org/valhalla.git pull/1049/head:pull/1049

PR: https://git.openjdk.org/valhalla/pull/1049