[jdk17u-dev] RFR: 8316566: RISC-V: Zero extended narrow oop passed to Atomic::cmpxchg

[Robbin Ehn]

Hi all,

This pull request contains a backport of commit [9ffec67a](https://github.com/openjdk/jdk21u/commit/9ffec67a3f2dada329a9887338c570424a79e7f8) from the [openjdk/jdk21u](https://git.openjdk.org/jdk21u) repository.

The commit being backported was authored by Robbin Ehn on 4 Oct 2023 and had no reviewers.

Thanks!

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Commit messages:
 - Backport 9ffec67a3f2dada329a9887338c570424a79e7f8

Changes: https://git.openjdk.org/jdk17u-dev/pull/1858/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=1858&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8316566
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/1858.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/1858/head:pull/1858

PR: https://git.openjdk.org/jdk17u-dev/pull/1858