[jdk21u-dev] RFR: 8325277: [21u] compiler/c2/cr7200264/TestIntVect.java fails after JDK-8291809 with fastdebug build on aarch64 platform with SVE

[SendaoYan]

Hi all,

As discuss in [JDK-8325277](https://bugs.openjdk.org/browse/JDK-8325277), we want to backout the "backport JDK-8291809 to jdk21u-dev".

The test_divc and test_divc_n cannot be vectorized on 128-bit vector platforms with JDK 21u due to algorithmic constraints in superword.cpp, which led to the reported failure in [JDK-8325277](https://bugs.openjdk.org/browse/JDK-8325277).
Starting from JDK 23, the algorithm has been significantly improved, and both cases can now be vectorized on 128-bit platforms, allowing the test to pass.

Test-fix only, risk is low.

Testing:

- [ ] Run tests compiler/c2/cr7200264/TestSSE2IntVect.java compiler/c2/cr7200264/TestSSE4IntVect.java on linux-x64
- [ ] Run tests compiler/c2/cr7200264/TestSSE2IntVect.java compiler/c2/cr7200264/TestSSE4IntVect.java on linux-aarch64 without SVE2
- [ ] Run tests compiler/c2/cr7200264/TestSSE2IntVect.java compiler/c2/cr7200264/TestSSE4IntVect.java on linux-aarch64 with SVE2

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Commit messages:
 - 8325277: [21u] compiler/c2/cr7200264/TestIntVect.java fails after JDK-8291809 with fastdebug build on aarch64 platform with SVE

Changes: https://git.openjdk.org/jdk21u-dev/pull/2381/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=2381&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8325277
  Stats: 1184 lines in 4 files changed: 322 ins; 408 del; 454 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/2381.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/2381/head:pull/2381

PR: https://git.openjdk.org/jdk21u-dev/pull/2381