RFR: 8340212: -Xshare:off -XX:CompressedClassSpaceBaseAddress=0x40001000000 crashes on macos-aarch64 [v10]

[Coleen Phillimore]

> Added checks to verify that the given compressed class base or shared base address and shift given will be decodable for aarch64.  This code is moved in PR https://github.com/openjdk/jdk/pull/20677 so this would be moved to the new place once that's integrated.
> 
> Tested with tier1-7.

Coleen Phillimore has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains 10 commits:

 - Merge branch 'master' into decode-mode
 - Recalculate decode mode if OS picks a different encoding.
 - Only calculate klass-decode-mode in one place.
 - Missed one. Another good reason to not copy code.
 - Rename ceil_log2 to log2i_ceil
 - Merge branch 'master' into decode-mode
 - Merge with incoming change for PR https://github.com/openjdk/jdk/pull/21932
 - Merge branch 'master' into decode-mode
 - include formatBuffer.hpp
 - 8340212: -Xshare:off -XX:CompressedClassSpaceBaseAddress=0x40001000000 crashes on macos-aarch64

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Changes: https://git.openjdk.org/jdk/pull/21695/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=21695&range=09
  Stats: 113 lines in 8 files changed: 94 ins; 7 del; 12 mod
  Patch: https://git.openjdk.org/jdk/pull/21695.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/21695/head:pull/21695

PR: https://git.openjdk.org/jdk/pull/21695