RFR: 8349944: [JMH] sun.misc.UnsafeOps cannot access class jdk.internal.misc.Unsafe [v2]

[Nicole Xu]

> The UnsafeOps JMH benchmark fails with the following error:
> 
>       java.lang.IllegalAccessError: class org.openjdk.bench.sun.misc.UnsafeOps (in unnamed module @0x520a3426) cannot access class jdk.internal.misc.Unsafe (in module java.base) because module java.base does not export jdk.internal.misc to unnamed module @0x520a3426
> 
> To resolve this, we add the required `--add-opens` flag to grant access for the benchmark.

Nicole Xu has updated the pull request incrementally with two additional commits since the last revision:

 - 8349944: [JMH] sun.misc.UnsafeOps cannot access class jdk.internal.misc.Unsafe
   
   The UnsafeOps JMH benchmark fails with the following error:
   
         ```
         java.lang.IllegalAccessError: class org.openjdk.bench.sun.misc.UnsafeOps (in unnamed module @0x520a3426) cannot access class jdk.internal.misc.Unsafe (in module java.base) because module java.base does not export jdk.internal.misc to unnamed module @0x520a3426
         ```
   
   Since this micro-benchmark is created for `sun.misc.Unsafe` rather than
   `jdk.internal.misc.Unsafe`, we change it back as before JDK-8332744.
   
   Note that even it will raise "proprietary API" warnings after this
   patch, it is acceptable because the relevant APIs are bound for removal
   for the integrity of the platform.
   
   Change-Id: Ia7c57c2ca09af4b2b3c6cc10ef4ae5a9f3c38a4c
 - Revert "8349944: [JMH] sun.misc.UnsafeOps cannot access class jdk.internal.misc.Unsafe"
   
   This reverts commit ebc32ae2c6e448075fedbdbb2b4879c43829c44b.

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/23686/files
  - new: https://git.openjdk.org/jdk/pull/23686/files/ebc32ae2..b2bbc24e

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=23686&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=23686&range=00-01

  Stats: 2 lines in 1 file changed: 0 ins; 1 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/23686.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/23686/head:pull/23686

PR: https://git.openjdk.org/jdk/pull/23686