RFR: 8255452: Doing GC during JVMTI MethodExit event posting breaks return oop [v2]

[Erik Österlund]

On Sat, 31 Oct 2020 09:54:09 GMT, Serguei Spitsyn <sspitsyn at openjdk.org> wrote:

> Hi Erik,
> 
> Nice discovery! Indeed, this is a long standing issue. It looks good in general.
> I agree with Coleen, it would be nice if there is an elegant way to move the oop_result saving/restoring code to InterpreterRuntime::post_method_exit. Otherwise, I'm okay with what you have now.
> It is also nice discovery of the issue with clearing the expression stack. I think, it was my mistake in the initial implementation of the ForceEarlyReturn when I followed the PopFrame implementation pattern. It is good to separate it from the current fix.
> 
> Thanks,
> Serguei

Thanks for reviewing this Serguei. And thanks for confirming our suspicions regarding clearing of the expression stack. I wasn't sure if anyone would be around that knew how it ended up there!
I made the refactoring that you and Coleen wanted, I think. Hope you like it!

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

PR: https://git.openjdk.java.net/jdk/pull/930