[jdk17u-dev] RFR: 8309119: [17u/11u] Redo JDK-8297951: C2: Create skeleton predicates for all If nodes in loop predication

[Goetz Lindenmaier]

…or all If nodes in loop predication

Redo of above change. 
The patch of 8308884 applied clean with -R.
Test passes.

I'll backport JDK-8307683, too.

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

Commit messages:
 - 8309119: [17u/11u] Redo JDK-8297951: C2: Create skeleton predicates for all If nodes in loop predication

Changes: https://git.openjdk.org/jdk17u-dev/pull/1497/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=1497&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8309119
  Stats: 7 lines in 1 file changed: 0 ins; 2 del; 5 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/1497.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/1497/head:pull/1497

PR: https://git.openjdk.org/jdk17u-dev/pull/1497