[jdk21u] RFR: 8320209: VectorMaskGen clobbers rflags on x86_64

[Sandhya Viswanathan]

8320209: VectorMaskGen clobbers rflags on x86_64

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Commit messages:
 - Backport b05e69f789fa8c9a5320be5a841317abd3b3a235

Changes: https://git.openjdk.org/jdk21u/pull/375/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk21u&pr=375&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8320209
  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk21u/pull/375.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u.git pull/375/head:pull/375

PR: https://git.openjdk.org/jdk21u/pull/375