[jdk11u-dev] RFR: 8253795: Implementation of JEP 391: macOS/AArch64 Port [v6]

[Vladimir Kempik]

> Initial version of JEP-391 backport to jdk11u.
> Build system changes are mostly clean, except cds disabling part, it's copy&paste from aix part.
> Things needing attention: os_bsd_aarch64.cpp and W^X transitions.
> serviceability agent is mostly clean.
> This passed GHA_tier1 testing.
> Full regression testing is running now on Azul's infra, will report/update PR when done.
> **Update: TCK passed, tier1/tier2 is almost good, needs #718**
> Sharing this PR slightly earlier to let other interested parties to run the tests too.
> Example of cross-building on intel mac (needs Xcode12/13):
> sh configure --with-boot-jdk=/Library/Java/JavaVirtualMachines/zulu-11.jdk/Contents/Home/ --with-build-jdk=/Library/Java/JavaVirtualMachines/zulu-11.jdk/Contents/Home/ --disable-warnings-as-errors --openjdk-target=aarch64-apple-darwin --with-extra-cflags='-arch arm64' --with-extra-ldflags='-arch arm64' --with-extra-cxxflags='-arch arm64'

Vladimir Kempik has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains ten additional commits since the last revision:

 - Merge branch 'master' into JDK-8253795
 - remove unused at_rsp from aarch64
 - Fix warning about c++11 extension
 - Exclude test CompressedClassPointers.java on macarm
 - Merge pull request #1 from VladimirKempik/JEP391_and_8262896
   
   8262896: [macos_aarch64] Crash in jni_fast_GetLongField
 - 8262896: [macos_aarch64] Crash in jni_fast_GetLongField
 - Trailing white space removal
 - Fix up linux_aarch64
 - Initial commit

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

Changes:
  - all: https://git.openjdk.java.net/jdk11u-dev/pull/715/files
  - new: https://git.openjdk.java.net/jdk11u-dev/pull/715/files/34cb67de..351be968

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk11u-dev&pr=715&range=05
 - incr: https://webrevs.openjdk.java.net/?repo=jdk11u-dev&pr=715&range=04-05

  Stats: 75 lines in 10 files changed: 56 ins; 1 del; 18 mod
  Patch: https://git.openjdk.java.net/jdk11u-dev/pull/715.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk11u-dev pull/715/head:pull/715

PR: https://git.openjdk.java.net/jdk11u-dev/pull/715