RFR: 8227745: Enable Escape Analysis for Better Performance in the Presence of JVMTI Agents [v14]

[Richard Reingruber]

> Hi,
> 
> this is the continuation of the review of the implementation for:
> 
> https://bugs.openjdk.java.net/browse/JDK-8227745
> https://bugs.openjdk.java.net/browse/JDK-8233915
> 
> It allows for JIT optimizations based on escape analysis even if JVMTI agents acquire capabilities to access references
> to objects that are subject to such optimizations, e.g. scalar replacement. The implementation reverts such
> optimizations just before access very much as when switching from JIT compiled execution to the interpreter, aka
> "deoptimization".  Webrev.8 was the last one before before the transition to Git/Github:
> 
> http://cr.openjdk.java.net/~rrich/webrevs/8227745/webrev.8/
> 
> Thanks, Richard.

Richard Reingruber has updated the pull request with a new target base due to a merge or a rebase. The pull request now
contains 29 commits:

 - Merge branch 'master' into JDK-8227745
 - Removed cross_modify_fence from JT::wait_for_object_deoptimization(). See JDK-8254264.
 - handle_special_runtime_exit_condition(): wait (blocked) for obj. deoptimization _before_ async ex. check.
 - Removed unused parameter from EscapeBarrierSuspendHandshake.
 - Adaptations to JDK-8254263: Remove special_runtime_exit_condition() check from ~ThreadInVMForHandshake()
   
   With JDK-8254263 the special_runtime_exit_condition() check was removed from
   ~ThreadInVMForHandshake() because now a thread never becomes unsafe when
   processing its own handshakes. EscapeBarrier uses handshakes to sync with the
   target thread for object deoptimization so we add a check for object
   deoptimization to ThreadSafepointState::handle_polling_page_exception().
   
   In JavaThread::wait_for_object_deoptimization() we must check
   is_obj_deopt_suspend() again after handshake/safepoint processing because a
   handshake for obj. deopt suspend could have been processed.
 - Adaptions to lazy/concurrent thread stack processing for ZGC (JEP 376)
 - EATests.java improvements
 - Merge branch 'master' into JDK-8227745
 - The constructor of StackFrameStream takes more parameters after JDK-8253180
 - Merge branch 'master' into JDK-8227745
 - ... and 19 more: https://git.openjdk.java.net/jdk/compare/1da28de8...8d09747b

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

Changes: https://git.openjdk.java.net/jdk/pull/119/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=119&range=13
  Stats: 5860 lines in 53 files changed: 5642 ins; 116 del; 102 mod
  Patch: https://git.openjdk.java.net/jdk/pull/119.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/119/head:pull/119

PR: https://git.openjdk.java.net/jdk/pull/119