RFR: 8343700: ceil_log2 should not loop endlessly [v3]

[Sonia Zaldana Calles]

> Hi all, 
> 
> This PR addresses [8343700](https://bugs.openjdk.org/browse/JDK-8343700) where ceil_log2 looped endlessly if the input value has the highest bit set. 
> 
> I also dealt with the case where we try to find ceil_log2(1) which would've returned 1 as opposed to 0. 
> 
> Cheers, 
> Sonia

Sonia Zaldana Calles has updated the pull request incrementally with one additional commit since the last revision:

  Starting ret at 0

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/22074/files
  - new: https://git.openjdk.org/jdk/pull/22074/files/0dd27068..f82cc31d

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=22074&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=22074&range=01-02

  Stats: 2 lines in 1 file changed: 0 ins; 1 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/22074.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/22074/head:pull/22074

PR: https://git.openjdk.org/jdk/pull/22074