RFR: 8363620: AArch64: reimplement emit_static_call_stub() [v6]

[Fei Gao]

On Tue, 16 Dec 2025 10:59:16 GMT, Andrew Haley <aph at openjdk.org> wrote:

> I can't really understand why that might matter. I do, though see a possible problem when two threads resolve the same call site. They both lock on`CompiledICLocker`, one wins the race, resolves the site. The other loses, exits, but it sees the patched call site with no intervening ISB. An ISB in `CompiledICLocker::~CompiledICLocker() ` would fix that.

@theRealAph Sorry, I don’t quite understand this point. If the second thread observes the patched stub without the ISB, does that mean it must have observed the patched B .+4 and also the updated MOV instructions, since the visibility of the MOVs is guaranteed to happen before the visibility of the B .+4? If so, what is the problem here? Thanks.

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

PR Comment: https://git.openjdk.org/jdk/pull/26638#issuecomment-3665046658