[jdk11u-dev] RFR: 8261147: C2: Node is wrongly marked as reduction resulting in a wrong execution due to wrong vector instructions

[Martin Doerr]

Almost clean backport of JDK-8261147. I had to insert the new hunk in node.cpp manually due to unrelated context changes from JDK-8255000.

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Commit messages:
 - Backport f791fdf23ef6e49e7e1ca68e33a16f6686e0bfa1

Changes: https://git.openjdk.java.net/jdk11u-dev/pull/164/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk11u-dev&pr=164&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8261147
  Stats: 79 lines in 3 files changed: 75 ins; 0 del; 4 mod
  Patch: https://git.openjdk.java.net/jdk11u-dev/pull/164.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk11u-dev pull/164/head:pull/164

PR: https://git.openjdk.java.net/jdk11u-dev/pull/164