RFR: 8295066: Folding of loads is broken in C2 after JDK-8242115

Tue Oct 25 20:00:26 UTC 2022

The fix does two things:

1. Allow folding of pinned loads to constants with a straight line data flow (no phis).
2. Make scalarization aware of the new shape of the barriers so that pre-loads can be ignored.

Testing is clean, Valhalla testing is clean too.

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Commit messages:
 - Add test
 - Fix scalarization
 - Allow direct constant folding

Changes: https://git.openjdk.org/jdk/pull/10861/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=10861&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8295066
  Stats: 260 lines in 9 files changed: 178 ins; 46 del; 36 mod
  Patch: https://git.openjdk.org/jdk/pull/10861.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/10861/head:pull/10861

PR: https://git.openjdk.org/jdk/pull/10861