Please review the implementation of JEP 391: macOS/AArch64 Port. It's heavily based on existing ports to linux/aarch64, macos/x86_64, and windows/aarch64.
Major changes are in: * src/hotspot/cpu/aarch64: support of the new calling convention (subtasks JDK-8253817, JDK-8253818) * src/hotspot/os_cpu/bsd_aarch64: copy of os_cpu/linux_aarch64 with necessary adjustments (JDK-8253819) * src/hotspot/share, test/hotspot/gtest: support of write-xor-execute (W^X), required on macOS/AArch64 platform. It's implemented with pthread_jit_write_protect_np provided by Apple. The W^X mode is local to a thread, so W^X mode change relates to the java thread state change (for java threads). In most cases, JVM executes in write-only mode, except when calling a generated stub like SafeFetch, which requires a temporary switch to execute-only mode. The same execute-only mode is enabled when a java thread executes in java or native states. This approach of managing W^X mode turned out to be simple and efficient enough. * src/jdk.hotspot.agent: serviceability agent implementation (JDK-8254941) ------------- Commit messages: - Fix build - JDK-8253816: Update after recent changes - Rework gtests to always have wx_write - Revert gtest changes - Fix gtests in debug - Merge remote-tracking branch 'upstream/master' into jdk-macos - Fix windows_aarch64 - Use r18_tls instead of r18_reserved - JDK-8253742: bsd_aarch64 part - JDK-8257882: bsd_aarch64 part - ... and 40 more: https://git.openjdk.java.net/jdk/compare/82adfb32...3d4f4c23 Changes: https://git.openjdk.java.net/jdk/pull/2200/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=2200&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8253795 Stats: 3335 lines in 117 files changed: 3230 ins; 41 del; 64 mod Patch: https://git.openjdk.java.net/jdk/pull/2200.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/2200/head:pull/2200 PR: https://git.openjdk.java.net/jdk/pull/2200
