RFR: 8260473: [vector] ZGC: VectorReshape test produces incorrect results with ZGC enabled

[王超]

https://bugs.openjdk.java.net/browse/JDK-8260473

Function "PhaseVector::expand_vunbox_node" creates a LoadNode, but forgets to make the LoadNode to pass gc barriers.


Testing: all Vector API related tests have passed.

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Commit messages:
 - 8260473: [vector] ZGC: VectorReshape test produces incorrect results with ZGC enabled

Changes: https://git.openjdk.java.net/jdk/pull/2253/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=2253&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8260473
  Stats: 12 lines in 1 file changed: 3 ins; 0 del; 9 mod
  Patch: https://git.openjdk.java.net/jdk/pull/2253.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/2253/head:pull/2253

PR: https://git.openjdk.java.net/jdk/pull/2253