RFR: 8265702: ZGC on macOS/aarch64

[David Holmes]

On Wed, 21 Apr 2021 21:10:02 GMT, Per Liden <pliden at openjdk.org> wrote:

> This patch enables ZGC on macOS/aarch64. It does three things:
> 1) Enables building of ZGC on this platform.
> 2) Adds `os::processor_id()`, which for now always returns 0.
> 3) Fixes a WX issue in `OptoRuntime::handle_exception_C()`, where the stackwater mark might unnecessarily process a frame when the thread is in WXExec mode. In this case, the we're not touching any oops, so we don't need to process any frames.
> 
> Testing: Passes the same tests as macOS/x86_64 (with the exception of pre-existing issues unrelated to ZGC).

Hi Per,

Looks good. One minor nit.

Thanks,
David

src/hotspot/os/bsd/os_bsd.cpp line 2149:

> 2147: 
> 2148:   return (uint)processor_id;
> 2149: #else

Please add a comment indicating what platform this else is referring to.

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Marked as reviewed by dholmes (Reviewer).

PR: https://git.openjdk.java.net/jdk/pull/3609