RFR: 8291649: multiple tests failing with -Xcomp after JDK-8290034

[Jatin Bhateja]

Hi,

This bug fix patch fixes the incorrect computation during constant folding of Reverse[IL] IR node.
A new utility class has been added to optimize computation of reverse_bit operation using GCC built-ins.

Kindly review and share your feedback.

Best Regards,
Jatin

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

Commit messages:
 - 8291649: Removing failing tests from ProblemList-Xcomp.txt
 - 8291649: multiple tests failing with -Xcomp after JDK-8290034

Changes: https://git.openjdk.org/jdk/pull/9987/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=9987&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8291649
  Stats: 175 lines in 5 files changed: 156 ins; 17 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/9987.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/9987/head:pull/9987

PR: https://git.openjdk.org/jdk/pull/9987